diff options
Diffstat (limited to 'drivers/i2c')
180 files changed, 106023 insertions, 0 deletions
diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig new file mode 100644 index 000000000..9388823bb --- /dev/null +++ b/drivers/i2c/Kconfig @@ -0,0 +1,173 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# I2C subsystem configuration +# + +menu "I2C support" + +config I2C + tristate "I2C support" + select RT_MUTEXES + select IRQ_DOMAIN + help + I2C (pronounce: I-squared-C) is a slow serial bus protocol used in + many micro controller applications and developed by Philips. SMBus, + or System Management Bus is a subset of the I2C protocol. More + information is contained in the directory <file:Documentation/i2c/>, + especially in the file called "summary" there. + + Both I2C and SMBus are supported here. You will need this for + hardware sensors support, and also for Video For Linux support. + + If you want I2C support, you should say Y here and also to the + specific driver for your bus adapter(s) below. + + This I2C support can also be built as a module. If so, the module + will be called i2c-core. + +config ACPI_I2C_OPREGION + bool "ACPI I2C Operation region support" + depends on I2C=y && ACPI + default y + help + Say Y here if you want to enable ACPI I2C operation region support. + Operation Regions allow firmware (BIOS) code to access I2C slave devices, + such as smart batteries through an I2C host controller driver. + +if I2C + +config I2C_BOARDINFO + bool + default y + +config I2C_COMPAT + bool "Enable compatibility bits for old user-space" + default y + help + Say Y here if you intend to run lm-sensors 3.1.1 or older, or any + other user-space package which expects i2c adapters to be class + devices. If you don't know, say Y. + +config I2C_CHARDEV + tristate "I2C device interface" + help + Say Y here to use i2c-* device files, usually found in the /dev + directory on your system. They make it possible to have user-space + programs use the I2C bus. Information on how to do this is + contained in the file <file:Documentation/i2c/dev-interface.rst>. + + This support is also available as a module. If so, the module + will be called i2c-dev. + +config I2C_MUX + tristate "I2C bus multiplexing support" + help + Say Y here if you want the I2C core to support the ability to + handle multiplexed I2C bus topologies, by presenting each + multiplexed segment as a I2C adapter. + + This support is also available as a module. If so, the module + will be called i2c-mux. + +source "drivers/i2c/muxes/Kconfig" + +config I2C_ATR + tristate "I2C Address Translator (ATR) support" if COMPILE_TEST + help + Enable support for I2C Address Translator (ATR) chips. + + An ATR allows accessing multiple I2C busses from a single + physical bus via address translation instead of bus selection as + i2c-muxes do. + +config I2C_HELPER_AUTO + bool "Autoselect pertinent helper modules" + default y + help + Some I2C bus drivers require so-called "I2C algorithm" modules + to work. These are basically software-only abstractions of generic + I2C interfaces. This option will autoselect them so that you don't + have to care. + + Unselect this only if you need to enable additional helper + modules, for example for use with external I2C bus drivers. + + In doubt, say Y. + +config I2C_SMBUS + tristate "SMBus-specific protocols" if !I2C_HELPER_AUTO + help + Say Y here if you want support for SMBus extensions to the I2C + specification. At the moment, two extensions are supported: + the SMBus Alert protocol and the SMBus Host Notify protocol. + + This support is also available as a module. If so, the module + will be called i2c-smbus. + +source "drivers/i2c/algos/Kconfig" +source "drivers/i2c/busses/Kconfig" + +config I2C_STUB + tristate "I2C/SMBus Test Stub" + depends on m + help + This module may be useful to developers of SMBus client drivers, + especially for certain kinds of sensor chips. + + If you do build this module, be sure to read the notes and warnings + in <file:Documentation/i2c/i2c-stub.rst>. + + If you don't know what to do here, definitely say N. + +config I2C_SLAVE + bool "I2C slave support" + help + This enables Linux to act as an I2C slave device. Note that your I2C + bus master driver also needs to support this functionality. Please + read Documentation/i2c/slave-interface.rst for further details. + +if I2C_SLAVE + +config I2C_SLAVE_EEPROM + tristate "I2C eeprom slave driver" + help + This backend makes Linux behave like an I2C EEPROM. Please read + Documentation/i2c/slave-eeprom-backend.rst for further details. + +config I2C_SLAVE_TESTUNIT + tristate "I2C eeprom testunit driver" + help + This backend can be used to trigger test cases for I2C bus masters + which require a remote device with certain capabilities, e.g. + multi-master, SMBus Host Notify, etc. Please read + Documentation/i2c/slave-testunit-backend.rst for further details. + +endif + +config I2C_DEBUG_CORE + bool "I2C Core debugging messages" + help + Say Y here if you want the I2C core to produce a bunch of debug + messages to the system log. Select this if you are having a + problem with I2C support and want to see more of what is going on. + +config I2C_DEBUG_ALGO + bool "I2C Algorithm debugging messages" + help + Say Y here if you want the I2C algorithm drivers to produce a bunch + of debug messages to the system log. Select this if you are having + a problem with I2C support and want to see more of what is going + on. + +config I2C_DEBUG_BUS + bool "I2C Bus debugging messages" + depends on HAS_IOMEM + help + Say Y here if you want the I2C bus drivers to produce a bunch of + debug messages to the system log. Select this if you are having + a problem with I2C support and want to see more of what is going + on. + +endif # I2C + +endmenu diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile new file mode 100644 index 000000000..3f71ce471 --- /dev/null +++ b/drivers/i2c/Makefile @@ -0,0 +1,22 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for the i2c core. +# + +obj-$(CONFIG_I2C_BOARDINFO) += i2c-boardinfo.o +obj-$(CONFIG_I2C) += i2c-core.o +i2c-core-objs := i2c-core-base.o i2c-core-smbus.o +i2c-core-$(CONFIG_ACPI) += i2c-core-acpi.o +i2c-core-$(CONFIG_I2C_SLAVE) += i2c-core-slave.o +i2c-core-$(CONFIG_OF) += i2c-core-of.o + +obj-$(CONFIG_I2C_SMBUS) += i2c-smbus.o +obj-$(CONFIG_I2C_CHARDEV) += i2c-dev.o +obj-$(CONFIG_I2C_MUX) += i2c-mux.o +obj-$(CONFIG_I2C_ATR) += i2c-atr.o +obj-y += algos/ busses/ muxes/ +obj-$(CONFIG_I2C_STUB) += i2c-stub.o +obj-$(CONFIG_I2C_SLAVE_EEPROM) += i2c-slave-eeprom.o +obj-$(CONFIG_I2C_SLAVE_TESTUNIT) += i2c-slave-testunit.o + +ccflags-$(CONFIG_I2C_DEBUG_CORE) := -DDEBUG diff --git a/drivers/i2c/algos/Kconfig b/drivers/i2c/algos/Kconfig new file mode 100644 index 000000000..aea523529 --- /dev/null +++ b/drivers/i2c/algos/Kconfig @@ -0,0 +1,18 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# I2C algorithm drivers configuration +# + +menu "I2C Algorithms" + visible if !I2C_HELPER_AUTO + +config I2C_ALGOBIT + tristate "I2C bit-banging interfaces" + +config I2C_ALGOPCF + tristate "I2C PCF 8584 interfaces" + +config I2C_ALGOPCA + tristate "I2C PCA 9564 interfaces" + +endmenu diff --git a/drivers/i2c/algos/Makefile b/drivers/i2c/algos/Makefile new file mode 100644 index 000000000..9b319a30d --- /dev/null +++ b/drivers/i2c/algos/Makefile @@ -0,0 +1,10 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Makefile for the i2c algorithms +# + +obj-$(CONFIG_I2C_ALGOBIT) += i2c-algo-bit.o +obj-$(CONFIG_I2C_ALGOPCF) += i2c-algo-pcf.o +obj-$(CONFIG_I2C_ALGOPCA) += i2c-algo-pca.o + +ccflags-$(CONFIG_I2C_DEBUG_ALGO) := -DDEBUG diff --git a/drivers/i2c/algos/i2c-algo-bit.c b/drivers/i2c/algos/i2c-algo-bit.c new file mode 100644 index 000000000..eddf25b90 --- /dev/null +++ b/drivers/i2c/algos/i2c-algo-bit.c @@ -0,0 +1,688 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * i2c-algo-bit.c: i2c driver algorithms for bit-shift adapters + * + * Copyright (C) 1995-2000 Simon G. Vogl + * + * With some changes from Frodo Looijaard <frodol@dds.nl>, Kyösti Mälkki + * <kmalkki@cc.hut.fi> and Jean Delvare <jdelvare@suse.de> + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/sched.h> +#include <linux/i2c.h> +#include <linux/i2c-algo-bit.h> + + +/* ----- global defines ----------------------------------------------- */ + +#ifdef DEBUG +#define bit_dbg(level, dev, format, args...) \ + do { \ + if (i2c_debug >= level) \ + dev_dbg(dev, format, ##args); \ + } while (0) +#else +#define bit_dbg(level, dev, format, args...) \ + do {} while (0) +#endif /* DEBUG */ + +/* ----- global variables --------------------------------------------- */ + +static int bit_test; /* see if the line-setting functions work */ +module_param(bit_test, int, S_IRUGO); +MODULE_PARM_DESC(bit_test, "lines testing - 0 off; 1 report; 2 fail if stuck"); + +#ifdef DEBUG +static int i2c_debug = 1; +module_param(i2c_debug, int, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(i2c_debug, + "debug level - 0 off; 1 normal; 2 verbose; 3 very verbose"); +#endif + +/* --- setting states on the bus with the right timing: --------------- */ + +#define setsda(adap, val) adap->setsda(adap->data, val) +#define setscl(adap, val) adap->setscl(adap->data, val) +#define getsda(adap) adap->getsda(adap->data) +#define getscl(adap) adap->getscl(adap->data) + +static inline void sdalo(struct i2c_algo_bit_data *adap) +{ + setsda(adap, 0); + udelay((adap->udelay + 1) / 2); +} + +static inline void sdahi(struct i2c_algo_bit_data *adap) +{ + setsda(adap, 1); + udelay((adap->udelay + 1) / 2); +} + +static inline void scllo(struct i2c_algo_bit_data *adap) +{ + setscl(adap, 0); + udelay(adap->udelay / 2); +} + +/* + * Raise scl line, and do checking for delays. This is necessary for slower + * devices. + */ +static int sclhi(struct i2c_algo_bit_data *adap) +{ + unsigned long start; + + setscl(adap, 1); + + /* Not all adapters have scl sense line... */ + if (!adap->getscl) + goto done; + + start = jiffies; + while (!getscl(adap)) { + /* This hw knows how to read the clock line, so we wait + * until it actually gets high. This is safer as some + * chips may hold it low ("clock stretching") while they + * are processing data internally. + */ + if (time_after(jiffies, start + adap->timeout)) { + /* Test one last time, as we may have been preempted + * between last check and timeout test. + */ + if (getscl(adap)) + break; + return -ETIMEDOUT; + } + cpu_relax(); + } +#ifdef DEBUG + if (jiffies != start && i2c_debug >= 3) + pr_debug("i2c-algo-bit: needed %ld jiffies for SCL to go high\n", + jiffies - start); +#endif + +done: + udelay(adap->udelay); + return 0; +} + + +/* --- other auxiliary functions -------------------------------------- */ +static void i2c_start(struct i2c_algo_bit_data *adap) +{ + /* assert: scl, sda are high */ + setsda(adap, 0); + udelay(adap->udelay); + scllo(adap); +} + +static void i2c_repstart(struct i2c_algo_bit_data *adap) +{ + /* assert: scl is low */ + sdahi(adap); + sclhi(adap); + setsda(adap, 0); + udelay(adap->udelay); + scllo(adap); +} + + +static void i2c_stop(struct i2c_algo_bit_data *adap) +{ + /* assert: scl is low */ + sdalo(adap); + sclhi(adap); + setsda(adap, 1); + udelay(adap->udelay); +} + + + +/* send a byte without start cond., look for arbitration, + check ackn. from slave */ +/* returns: + * 1 if the device acknowledged + * 0 if the device did not ack + * -ETIMEDOUT if an error occurred (while raising the scl line) + */ +static int i2c_outb(struct i2c_adapter *i2c_adap, unsigned char c) +{ + int i; + int sb; + int ack; + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + + /* assert: scl is low */ + for (i = 7; i >= 0; i--) { + sb = (c >> i) & 1; + setsda(adap, sb); + udelay((adap->udelay + 1) / 2); + if (sclhi(adap) < 0) { /* timed out */ + bit_dbg(1, &i2c_adap->dev, + "i2c_outb: 0x%02x, timeout at bit #%d\n", + (int)c, i); + return -ETIMEDOUT; + } + /* FIXME do arbitration here: + * if (sb && !getsda(adap)) -> ouch! Get out of here. + * + * Report a unique code, so higher level code can retry + * the whole (combined) message and *NOT* issue STOP. + */ + scllo(adap); + } + sdahi(adap); + if (sclhi(adap) < 0) { /* timeout */ + bit_dbg(1, &i2c_adap->dev, + "i2c_outb: 0x%02x, timeout at ack\n", (int)c); + return -ETIMEDOUT; + } + + /* read ack: SDA should be pulled down by slave, or it may + * NAK (usually to report problems with the data we wrote). + * Always report ACK if SDA is write-only. + */ + ack = !adap->getsda || !getsda(adap); /* ack: sda is pulled low -> success */ + bit_dbg(2, &i2c_adap->dev, "i2c_outb: 0x%02x %s\n", (int)c, + ack ? "A" : "NA"); + + scllo(adap); + return ack; + /* assert: scl is low (sda undef) */ +} + + +static int i2c_inb(struct i2c_adapter *i2c_adap) +{ + /* read byte via i2c port, without start/stop sequence */ + /* acknowledge is sent in i2c_read. */ + int i; + unsigned char indata = 0; + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + + /* assert: scl is low */ + sdahi(adap); + for (i = 0; i < 8; i++) { + if (sclhi(adap) < 0) { /* timeout */ + bit_dbg(1, &i2c_adap->dev, + "i2c_inb: timeout at bit #%d\n", + 7 - i); + return -ETIMEDOUT; + } + indata *= 2; + if (getsda(adap)) + indata |= 0x01; + setscl(adap, 0); + udelay(i == 7 ? adap->udelay / 2 : adap->udelay); + } + /* assert: scl is low */ + return indata; +} + +/* + * Sanity check for the adapter hardware - check the reaction of + * the bus lines only if it seems to be idle. + */ +static int test_bus(struct i2c_adapter *i2c_adap) +{ + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + const char *name = i2c_adap->name; + int scl, sda, ret; + + if (adap->pre_xfer) { + ret = adap->pre_xfer(i2c_adap); + if (ret < 0) + return -ENODEV; + } + + if (adap->getsda == NULL) + pr_info("%s: SDA is write-only, testing not possible\n", name); + if (adap->getscl == NULL) + pr_info("%s: SCL is write-only, testing not possible\n", name); + + sda = adap->getsda ? getsda(adap) : 1; + scl = adap->getscl ? getscl(adap) : 1; + if (!scl || !sda) { + pr_warn("%s: bus seems to be busy (scl=%d, sda=%d)\n", name, scl, sda); + goto bailout; + } + + sdalo(adap); + if (adap->getsda && getsda(adap)) { + pr_warn("%s: SDA stuck high!\n", name); + goto bailout; + } + if (adap->getscl && !getscl(adap)) { + pr_warn("%s: SCL unexpected low while pulling SDA low!\n", name); + goto bailout; + } + + sdahi(adap); + if (adap->getsda && !getsda(adap)) { + pr_warn("%s: SDA stuck low!\n", name); + goto bailout; + } + if (adap->getscl && !getscl(adap)) { + pr_warn("%s: SCL unexpected low while pulling SDA high!\n", name); + goto bailout; + } + + scllo(adap); + if (adap->getscl && getscl(adap)) { + pr_warn("%s: SCL stuck high!\n", name); + goto bailout; + } + if (adap->getsda && !getsda(adap)) { + pr_warn("%s: SDA unexpected low while pulling SCL low!\n", name); + goto bailout; + } + + sclhi(adap); + if (adap->getscl && !getscl(adap)) { + pr_warn("%s: SCL stuck low!\n", name); + goto bailout; + } + if (adap->getsda && !getsda(adap)) { + pr_warn("%s: SDA unexpected low while pulling SCL high!\n", name); + goto bailout; + } + + if (adap->post_xfer) + adap->post_xfer(i2c_adap); + + pr_info("%s: Test OK\n", name); + return 0; +bailout: + sdahi(adap); + sclhi(adap); + + if (adap->post_xfer) + adap->post_xfer(i2c_adap); + + return -ENODEV; +} + +/* ----- Utility functions + */ + +/* try_address tries to contact a chip for a number of + * times before it gives up. + * return values: + * 1 chip answered + * 0 chip did not answer + * -x transmission error + */ +static int try_address(struct i2c_adapter *i2c_adap, + unsigned char addr, int retries) +{ + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + int i, ret = 0; + + for (i = 0; i <= retries; i++) { + ret = i2c_outb(i2c_adap, addr); + if (ret == 1 || i == retries) + break; + bit_dbg(3, &i2c_adap->dev, "emitting stop condition\n"); + i2c_stop(adap); + udelay(adap->udelay); + yield(); + bit_dbg(3, &i2c_adap->dev, "emitting start condition\n"); + i2c_start(adap); + } + if (i && ret) + bit_dbg(1, &i2c_adap->dev, + "Used %d tries to %s client at 0x%02x: %s\n", i + 1, + addr & 1 ? "read from" : "write to", addr >> 1, + ret == 1 ? "success" : "failed, timeout?"); + return ret; +} + +static int sendbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg) +{ + const unsigned char *temp = msg->buf; + int count = msg->len; + unsigned short nak_ok = msg->flags & I2C_M_IGNORE_NAK; + int retval; + int wrcount = 0; + + while (count > 0) { + retval = i2c_outb(i2c_adap, *temp); + + /* OK/ACK; or ignored NAK */ + if ((retval > 0) || (nak_ok && (retval == 0))) { + count--; + temp++; + wrcount++; + + /* A slave NAKing the master means the slave didn't like + * something about the data it saw. For example, maybe + * the SMBus PEC was wrong. + */ + } else if (retval == 0) { + dev_err(&i2c_adap->dev, "sendbytes: NAK bailout.\n"); + return -EIO; + + /* Timeout; or (someday) lost arbitration + * + * FIXME Lost ARB implies retrying the transaction from + * the first message, after the "winning" master issues + * its STOP. As a rule, upper layer code has no reason + * to know or care about this ... it is *NOT* an error. + */ + } else { + dev_err(&i2c_adap->dev, "sendbytes: error %d\n", + retval); + return retval; + } + } + return wrcount; +} + +static int acknak(struct i2c_adapter *i2c_adap, int is_ack) +{ + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + + /* assert: sda is high */ + if (is_ack) /* send ack */ + setsda(adap, 0); + udelay((adap->udelay + 1) / 2); + if (sclhi(adap) < 0) { /* timeout */ + dev_err(&i2c_adap->dev, "readbytes: ack/nak timeout\n"); + return -ETIMEDOUT; + } + scllo(adap); + return 0; +} + +static int readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg) +{ + int inval; + int rdcount = 0; /* counts bytes read */ + unsigned char *temp = msg->buf; + int count = msg->len; + const unsigned flags = msg->flags; + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + + if (!adap->getsda) + return -EOPNOTSUPP; + + while (count > 0) { + inval = i2c_inb(i2c_adap); + if (inval >= 0) { + *temp = inval; + rdcount++; + } else { /* read timed out */ + break; + } + + temp++; + count--; + + /* Some SMBus transactions require that we receive the + transaction length as the first read byte. */ + if (rdcount == 1 && (flags & I2C_M_RECV_LEN)) { + if (inval <= 0 || inval > I2C_SMBUS_BLOCK_MAX) { + if (!(flags & I2C_M_NO_RD_ACK)) + acknak(i2c_adap, 0); + dev_err(&i2c_adap->dev, + "readbytes: invalid block length (%d)\n", + inval); + return -EPROTO; + } + /* The original count value accounts for the extra + bytes, that is, either 1 for a regular transaction, + or 2 for a PEC transaction. */ + count += inval; + msg->len += inval; + } + + bit_dbg(2, &i2c_adap->dev, "readbytes: 0x%02x %s\n", + inval, + (flags & I2C_M_NO_RD_ACK) + ? "(no ack/nak)" + : (count ? "A" : "NA")); + + if (!(flags & I2C_M_NO_RD_ACK)) { + inval = acknak(i2c_adap, count); + if (inval < 0) + return inval; + } + } + return rdcount; +} + +/* doAddress initiates the transfer by generating the start condition (in + * try_address) and transmits the address in the necessary format to handle + * reads, writes as well as 10bit-addresses. + * returns: + * 0 everything went okay, the chip ack'ed, or IGNORE_NAK flag was set + * -x an error occurred (like: -ENXIO if the device did not answer, or + * -ETIMEDOUT, for example if the lines are stuck...) + */ +static int bit_doAddress(struct i2c_adapter *i2c_adap, struct i2c_msg *msg) +{ + unsigned short flags = msg->flags; + unsigned short nak_ok = msg->flags & I2C_M_IGNORE_NAK; + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + + unsigned char addr; + int ret, retries; + + retries = nak_ok ? 0 : i2c_adap->retries; + + if (flags & I2C_M_TEN) { + /* a ten bit address */ + addr = 0xf0 | ((msg->addr >> 7) & 0x06); + bit_dbg(2, &i2c_adap->dev, "addr0: %d\n", addr); + /* try extended address code...*/ + ret = try_address(i2c_adap, addr, retries); + if ((ret != 1) && !nak_ok) { + dev_err(&i2c_adap->dev, + "died at extended address code\n"); + return -ENXIO; + } + /* the remaining 8 bit address */ + ret = i2c_outb(i2c_adap, msg->addr & 0xff); + if ((ret != 1) && !nak_ok) { + /* the chip did not ack / xmission error occurred */ + dev_err(&i2c_adap->dev, "died at 2nd address code\n"); + return -ENXIO; + } + if (flags & I2C_M_RD) { + bit_dbg(3, &i2c_adap->dev, + "emitting repeated start condition\n"); + i2c_repstart(adap); + /* okay, now switch into reading mode */ + addr |= 0x01; + ret = try_address(i2c_adap, addr, retries); + if ((ret != 1) && !nak_ok) { + dev_err(&i2c_adap->dev, + "died at repeated address code\n"); + return -EIO; + } + } + } else { /* normal 7bit address */ + addr = i2c_8bit_addr_from_msg(msg); + if (flags & I2C_M_REV_DIR_ADDR) + addr ^= 1; + ret = try_address(i2c_adap, addr, retries); + if ((ret != 1) && !nak_ok) + return -ENXIO; + } + + return 0; +} + +static int bit_xfer(struct i2c_adapter *i2c_adap, + struct i2c_msg msgs[], int num) +{ + struct i2c_msg *pmsg; + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + int i, ret; + unsigned short nak_ok; + + if (adap->pre_xfer) { + ret = adap->pre_xfer(i2c_adap); + if (ret < 0) + return ret; + } + + bit_dbg(3, &i2c_adap->dev, "emitting start condition\n"); + i2c_start(adap); + for (i = 0; i < num; i++) { + pmsg = &msgs[i]; + nak_ok = pmsg->flags & I2C_M_IGNORE_NAK; + if (!(pmsg->flags & I2C_M_NOSTART)) { + if (i) { + if (msgs[i - 1].flags & I2C_M_STOP) { + bit_dbg(3, &i2c_adap->dev, + "emitting enforced stop/start condition\n"); + i2c_stop(adap); + i2c_start(adap); + } else { + bit_dbg(3, &i2c_adap->dev, + "emitting repeated start condition\n"); + i2c_repstart(adap); + } + } + ret = bit_doAddress(i2c_adap, pmsg); + if ((ret != 0) && !nak_ok) { + bit_dbg(1, &i2c_adap->dev, + "NAK from device addr 0x%02x msg #%d\n", + msgs[i].addr, i); + goto bailout; + } + } + if (pmsg->flags & I2C_M_RD) { + /* read bytes into buffer*/ + ret = readbytes(i2c_adap, pmsg); + if (ret >= 1) + bit_dbg(2, &i2c_adap->dev, "read %d byte%s\n", + ret, ret == 1 ? "" : "s"); + if (ret < pmsg->len) { + if (ret >= 0) + ret = -EIO; + goto bailout; + } + } else { + /* write bytes from buffer */ + ret = sendbytes(i2c_adap, pmsg); + if (ret >= 1) + bit_dbg(2, &i2c_adap->dev, "wrote %d byte%s\n", + ret, ret == 1 ? "" : "s"); + if (ret < pmsg->len) { + if (ret >= 0) + ret = -EIO; + goto bailout; + } + } + } + ret = i; + +bailout: + bit_dbg(3, &i2c_adap->dev, "emitting stop condition\n"); + i2c_stop(adap); + + if (adap->post_xfer) + adap->post_xfer(i2c_adap); + return ret; +} + +/* + * We print a warning when we are not flagged to support atomic transfers but + * will try anyhow. That's what the I2C core would do as well. Sadly, we can't + * modify the algorithm struct at probe time because this struct is exported + * 'const'. + */ +static int bit_xfer_atomic(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], + int num) +{ + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + + if (!adap->can_do_atomic) + dev_warn(&i2c_adap->dev, "not flagged for atomic transfers\n"); + + return bit_xfer(i2c_adap, msgs, num); +} + +static u32 bit_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_NOSTART | I2C_FUNC_SMBUS_EMUL_ALL | + I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING; +} + + +/* -----exported algorithm data: ------------------------------------- */ + +const struct i2c_algorithm i2c_bit_algo = { + .master_xfer = bit_xfer, + .master_xfer_atomic = bit_xfer_atomic, + .functionality = bit_func, +}; +EXPORT_SYMBOL(i2c_bit_algo); + +static const struct i2c_adapter_quirks i2c_bit_quirk_no_clk_stretch = { + .flags = I2C_AQ_NO_CLK_STRETCH, +}; + +/* + * registering functions to load algorithms at runtime + */ +static int __i2c_bit_add_bus(struct i2c_adapter *adap, + int (*add_adapter)(struct i2c_adapter *)) +{ + struct i2c_algo_bit_data *bit_adap = adap->algo_data; + int ret; + + if (bit_test) { + ret = test_bus(adap); + if (bit_test >= 2 && ret < 0) + return -ENODEV; + } + + /* register new adapter to i2c module... */ + adap->algo = &i2c_bit_algo; + adap->retries = 3; + if (bit_adap->getscl == NULL) + adap->quirks = &i2c_bit_quirk_no_clk_stretch; + + /* + * We tried forcing SCL/SDA to an initial state here. But that caused a + * regression, sadly. Check Bugzilla #200045 for details. + */ + + ret = add_adapter(adap); + if (ret < 0) + return ret; + + if (bit_adap->getsda == NULL) + dev_warn(&adap->dev, "Not I2C compliant: can't read SDA\n"); + + if (bit_adap->getscl == NULL) + dev_warn(&adap->dev, "Not I2C compliant: can't read SCL\n"); + + if (bit_adap->getsda == NULL || bit_adap->getscl == NULL) + dev_warn(&adap->dev, "Bus may be unreliable\n"); + + return 0; +} + +int i2c_bit_add_bus(struct i2c_adapter *adap) +{ + return __i2c_bit_add_bus(adap, i2c_add_adapter); +} +EXPORT_SYMBOL(i2c_bit_add_bus); + +int i2c_bit_add_numbered_bus(struct i2c_adapter *adap) +{ + return __i2c_bit_add_bus(adap, i2c_add_numbered_adapter); +} +EXPORT_SYMBOL(i2c_bit_add_numbered_bus); + +MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); +MODULE_DESCRIPTION("I2C-Bus bit-banging algorithm"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/algos/i2c-algo-pca.c b/drivers/i2c/algos/i2c-algo-pca.c new file mode 100644 index 000000000..384af88e5 --- /dev/null +++ b/drivers/i2c/algos/i2c-algo-pca.c @@ -0,0 +1,561 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * i2c-algo-pca.c i2c driver algorithms for PCA9564 adapters + * Copyright (C) 2004 Arcom Control Systems + * Copyright (C) 2008 Pengutronix + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/delay.h> +#include <linux/jiffies.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/i2c-algo-pca.h> + +#define DEB1(fmt, args...) do { if (i2c_debug >= 1) \ + printk(KERN_DEBUG fmt, ## args); } while (0) +#define DEB2(fmt, args...) do { if (i2c_debug >= 2) \ + printk(KERN_DEBUG fmt, ## args); } while (0) +#define DEB3(fmt, args...) do { if (i2c_debug >= 3) \ + printk(KERN_DEBUG fmt, ## args); } while (0) + +static int i2c_debug; + +#define pca_outw(adap, reg, val) adap->write_byte(adap->data, reg, val) +#define pca_inw(adap, reg) adap->read_byte(adap->data, reg) + +#define pca_status(adap) pca_inw(adap, I2C_PCA_STA) +#define pca_clock(adap) adap->i2c_clock +#define pca_set_con(adap, val) pca_outw(adap, I2C_PCA_CON, val) +#define pca_get_con(adap) pca_inw(adap, I2C_PCA_CON) +#define pca_wait(adap) adap->wait_for_completion(adap->data) + +static void pca_reset(struct i2c_algo_pca_data *adap) +{ + if (adap->chip == I2C_PCA_CHIP_9665) { + /* Ignore the reset function from the module, + * we can use the parallel bus reset. + */ + pca_outw(adap, I2C_PCA_INDPTR, I2C_PCA_IPRESET); + pca_outw(adap, I2C_PCA_IND, 0xA5); + pca_outw(adap, I2C_PCA_IND, 0x5A); + + /* + * After a reset we need to re-apply any configuration + * (calculated in pca_init) to get the bus in a working state. + */ + pca_outw(adap, I2C_PCA_INDPTR, I2C_PCA_IMODE); + pca_outw(adap, I2C_PCA_IND, adap->bus_settings.mode); + pca_outw(adap, I2C_PCA_INDPTR, I2C_PCA_ISCLL); + pca_outw(adap, I2C_PCA_IND, adap->bus_settings.tlow); + pca_outw(adap, I2C_PCA_INDPTR, I2C_PCA_ISCLH); + pca_outw(adap, I2C_PCA_IND, adap->bus_settings.thi); + + pca_set_con(adap, I2C_PCA_CON_ENSIO); + } else { + adap->reset_chip(adap->data); + pca_set_con(adap, I2C_PCA_CON_ENSIO | adap->bus_settings.clock_freq); + } +} + +/* + * Generate a start condition on the i2c bus. + * + * returns after the start condition has occurred + */ +static int pca_start(struct i2c_algo_pca_data *adap) +{ + int sta = pca_get_con(adap); + DEB2("=== START\n"); + sta |= I2C_PCA_CON_STA; + sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_SI); + pca_set_con(adap, sta); + return pca_wait(adap); +} + +/* + * Generate a repeated start condition on the i2c bus + * + * return after the repeated start condition has occurred + */ +static int pca_repeated_start(struct i2c_algo_pca_data *adap) +{ + int sta = pca_get_con(adap); + DEB2("=== REPEATED START\n"); + sta |= I2C_PCA_CON_STA; + sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_SI); + pca_set_con(adap, sta); + return pca_wait(adap); +} + +/* + * Generate a stop condition on the i2c bus + * + * returns after the stop condition has been generated + * + * STOPs do not generate an interrupt or set the SI flag, since the + * part returns the idle state (0xf8). Hence we don't need to + * pca_wait here. + */ +static void pca_stop(struct i2c_algo_pca_data *adap) +{ + int sta = pca_get_con(adap); + DEB2("=== STOP\n"); + sta |= I2C_PCA_CON_STO; + sta &= ~(I2C_PCA_CON_STA|I2C_PCA_CON_SI); + pca_set_con(adap, sta); +} + +/* + * Send the slave address and R/W bit + * + * returns after the address has been sent + */ +static int pca_address(struct i2c_algo_pca_data *adap, + struct i2c_msg *msg) +{ + int sta = pca_get_con(adap); + int addr = i2c_8bit_addr_from_msg(msg); + + DEB2("=== SLAVE ADDRESS %#04x+%c=%#04x\n", + msg->addr, msg->flags & I2C_M_RD ? 'R' : 'W', addr); + + pca_outw(adap, I2C_PCA_DAT, addr); + + sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_STA|I2C_PCA_CON_SI); + pca_set_con(adap, sta); + + return pca_wait(adap); +} + +/* + * Transmit a byte. + * + * Returns after the byte has been transmitted + */ +static int pca_tx_byte(struct i2c_algo_pca_data *adap, + __u8 b) +{ + int sta = pca_get_con(adap); + DEB2("=== WRITE %#04x\n", b); + pca_outw(adap, I2C_PCA_DAT, b); + + sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_STA|I2C_PCA_CON_SI); + pca_set_con(adap, sta); + + return pca_wait(adap); +} + +/* + * Receive a byte + * + * returns immediately. + */ +static void pca_rx_byte(struct i2c_algo_pca_data *adap, + __u8 *b, int ack) +{ + *b = pca_inw(adap, I2C_PCA_DAT); + DEB2("=== READ %#04x %s\n", *b, ack ? "ACK" : "NACK"); +} + +/* + * Setup ACK or NACK for next received byte and wait for it to arrive. + * + * Returns after next byte has arrived. + */ +static int pca_rx_ack(struct i2c_algo_pca_data *adap, + int ack) +{ + int sta = pca_get_con(adap); + + sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_STA|I2C_PCA_CON_SI|I2C_PCA_CON_AA); + + if (ack) + sta |= I2C_PCA_CON_AA; + + pca_set_con(adap, sta); + return pca_wait(adap); +} + +static int pca_xfer(struct i2c_adapter *i2c_adap, + struct i2c_msg *msgs, + int num) +{ + struct i2c_algo_pca_data *adap = i2c_adap->algo_data; + struct i2c_msg *msg = NULL; + int curmsg; + int numbytes = 0; + int state; + int ret; + int completed = 1; + unsigned long timeout = jiffies + i2c_adap->timeout; + + while ((state = pca_status(adap)) != 0xf8) { + if (time_before(jiffies, timeout)) { + msleep(10); + } else { + dev_dbg(&i2c_adap->dev, "bus is not idle. status is " + "%#04x\n", state); + return -EBUSY; + } + } + + DEB1("{{{ XFER %d messages\n", num); + + if (i2c_debug >= 2) { + for (curmsg = 0; curmsg < num; curmsg++) { + int addr, i; + msg = &msgs[curmsg]; + + addr = (0x7f & msg->addr) ; + + if (msg->flags & I2C_M_RD) + printk(KERN_INFO " [%02d] RD %d bytes from %#02x [%#02x, ...]\n", + curmsg, msg->len, addr, (addr << 1) | 1); + else { + printk(KERN_INFO " [%02d] WR %d bytes to %#02x [%#02x%s", + curmsg, msg->len, addr, addr << 1, + msg->len == 0 ? "" : ", "); + for (i = 0; i < msg->len; i++) + printk("%#04x%s", msg->buf[i], i == msg->len - 1 ? "" : ", "); + printk("]\n"); + } + } + } + + curmsg = 0; + ret = -EIO; + while (curmsg < num) { + state = pca_status(adap); + + DEB3("STATE is 0x%02x\n", state); + msg = &msgs[curmsg]; + + switch (state) { + case 0xf8: /* On reset or stop the bus is idle */ + completed = pca_start(adap); + break; + + case 0x08: /* A START condition has been transmitted */ + case 0x10: /* A repeated start condition has been transmitted */ + completed = pca_address(adap, msg); + break; + + case 0x18: /* SLA+W has been transmitted; ACK has been received */ + case 0x28: /* Data byte in I2CDAT has been transmitted; ACK has been received */ + if (numbytes < msg->len) { + completed = pca_tx_byte(adap, + msg->buf[numbytes]); + numbytes++; + break; + } + curmsg++; numbytes = 0; + if (curmsg == num) + pca_stop(adap); + else + completed = pca_repeated_start(adap); + break; + + case 0x20: /* SLA+W has been transmitted; NOT ACK has been received */ + DEB2("NOT ACK received after SLA+W\n"); + pca_stop(adap); + ret = -ENXIO; + goto out; + + case 0x40: /* SLA+R has been transmitted; ACK has been received */ + completed = pca_rx_ack(adap, msg->len > 1); + break; + + case 0x50: /* Data bytes has been received; ACK has been returned */ + if (numbytes < msg->len) { + pca_rx_byte(adap, &msg->buf[numbytes], 1); + numbytes++; + completed = pca_rx_ack(adap, + numbytes < msg->len - 1); + break; + } + curmsg++; numbytes = 0; + if (curmsg == num) + pca_stop(adap); + else + completed = pca_repeated_start(adap); + break; + + case 0x48: /* SLA+R has been transmitted; NOT ACK has been received */ + DEB2("NOT ACK received after SLA+R\n"); + pca_stop(adap); + ret = -ENXIO; + goto out; + + case 0x30: /* Data byte in I2CDAT has been transmitted; NOT ACK has been received */ + DEB2("NOT ACK received after data byte\n"); + pca_stop(adap); + goto out; + + case 0x38: /* Arbitration lost during SLA+W, SLA+R or data bytes */ + DEB2("Arbitration lost\n"); + /* + * The PCA9564 data sheet (2006-09-01) says "A + * START condition will be transmitted when the + * bus becomes free (STOP or SCL and SDA high)" + * when the STA bit is set (p. 11). + * + * In case this won't work, try pca_reset() + * instead. + */ + pca_start(adap); + goto out; + + case 0x58: /* Data byte has been received; NOT ACK has been returned */ + if (numbytes == msg->len - 1) { + pca_rx_byte(adap, &msg->buf[numbytes], 0); + curmsg++; numbytes = 0; + if (curmsg == num) + pca_stop(adap); + else + completed = pca_repeated_start(adap); + } else { + DEB2("NOT ACK sent after data byte received. " + "Not final byte. numbytes %d. len %d\n", + numbytes, msg->len); + pca_stop(adap); + goto out; + } + break; + case 0x70: /* Bus error - SDA stuck low */ + DEB2("BUS ERROR - SDA Stuck low\n"); + pca_reset(adap); + goto out; + case 0x78: /* Bus error - SCL stuck low (PCA9665) */ + case 0x90: /* Bus error - SCL stuck low (PCA9564) */ + DEB2("BUS ERROR - SCL Stuck low\n"); + pca_reset(adap); + goto out; + case 0x00: /* Bus error during master or slave mode due to illegal START or STOP condition */ + DEB2("BUS ERROR - Illegal START or STOP\n"); + pca_reset(adap); + goto out; + default: + dev_err(&i2c_adap->dev, "unhandled SIO state 0x%02x\n", state); + break; + } + + if (!completed) + goto out; + } + + ret = curmsg; + out: + DEB1("}}} transferred %d/%d messages. " + "status is %#04x. control is %#04x\n", + curmsg, num, pca_status(adap), + pca_get_con(adap)); + return ret; +} + +static u32 pca_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm pca_algo = { + .master_xfer = pca_xfer, + .functionality = pca_func, +}; + +static unsigned int pca_probe_chip(struct i2c_adapter *adap) +{ + struct i2c_algo_pca_data *pca_data = adap->algo_data; + /* The trick here is to check if there is an indirect register + * available. If there is one, we will read the value we first + * wrote on I2C_PCA_IADR. Otherwise, we will read the last value + * we wrote on I2C_PCA_ADR + */ + pca_outw(pca_data, I2C_PCA_INDPTR, I2C_PCA_IADR); + pca_outw(pca_data, I2C_PCA_IND, 0xAA); + pca_outw(pca_data, I2C_PCA_INDPTR, I2C_PCA_ITO); + pca_outw(pca_data, I2C_PCA_IND, 0x00); + pca_outw(pca_data, I2C_PCA_INDPTR, I2C_PCA_IADR); + if (pca_inw(pca_data, I2C_PCA_IND) == 0xAA) { + printk(KERN_INFO "%s: PCA9665 detected.\n", adap->name); + pca_data->chip = I2C_PCA_CHIP_9665; + } else { + printk(KERN_INFO "%s: PCA9564 detected.\n", adap->name); + pca_data->chip = I2C_PCA_CHIP_9564; + } + return pca_data->chip; +} + +static int pca_init(struct i2c_adapter *adap) +{ + struct i2c_algo_pca_data *pca_data = adap->algo_data; + + adap->algo = &pca_algo; + + if (pca_probe_chip(adap) == I2C_PCA_CHIP_9564) { + static int freqs[] = {330, 288, 217, 146, 88, 59, 44, 36}; + int clock; + + if (pca_data->i2c_clock > 7) { + switch (pca_data->i2c_clock) { + case 330000: + pca_data->i2c_clock = I2C_PCA_CON_330kHz; + break; + case 288000: + pca_data->i2c_clock = I2C_PCA_CON_288kHz; + break; + case 217000: + pca_data->i2c_clock = I2C_PCA_CON_217kHz; + break; + case 146000: + pca_data->i2c_clock = I2C_PCA_CON_146kHz; + break; + case 88000: + pca_data->i2c_clock = I2C_PCA_CON_88kHz; + break; + case 59000: + pca_data->i2c_clock = I2C_PCA_CON_59kHz; + break; + case 44000: + pca_data->i2c_clock = I2C_PCA_CON_44kHz; + break; + case 36000: + pca_data->i2c_clock = I2C_PCA_CON_36kHz; + break; + default: + printk(KERN_WARNING + "%s: Invalid I2C clock speed selected." + " Using default 59kHz.\n", adap->name); + pca_data->i2c_clock = I2C_PCA_CON_59kHz; + } + } else { + printk(KERN_WARNING "%s: " + "Choosing the clock frequency based on " + "index is deprecated." + " Use the nominal frequency.\n", adap->name); + } + + clock = pca_clock(pca_data); + printk(KERN_INFO "%s: Clock frequency is %dkHz\n", + adap->name, freqs[clock]); + + /* Store settings as these will be needed when the PCA chip is reset */ + pca_data->bus_settings.clock_freq = clock; + + pca_reset(pca_data); + } else { + int clock; + int mode; + int tlow, thi; + /* Values can be found on PCA9665 datasheet section 7.3.2.6 */ + int min_tlow, min_thi; + /* These values are the maximum raise and fall values allowed + * by the I2C operation mode (Standard, Fast or Fast+) + * They are used (added) below to calculate the clock dividers + * of PCA9665. Note that they are slightly different of the + * real maximum, to allow the change on mode exactly on the + * maximum clock rate for each mode + */ + int raise_fall_time; + + if (pca_data->i2c_clock > 1265800) { + printk(KERN_WARNING "%s: I2C clock speed too high." + " Using 1265.8kHz.\n", adap->name); + pca_data->i2c_clock = 1265800; + } + + if (pca_data->i2c_clock < 60300) { + printk(KERN_WARNING "%s: I2C clock speed too low." + " Using 60.3kHz.\n", adap->name); + pca_data->i2c_clock = 60300; + } + + /* To avoid integer overflow, use clock/100 for calculations */ + clock = pca_clock(pca_data) / 100; + + if (pca_data->i2c_clock > I2C_MAX_FAST_MODE_PLUS_FREQ) { + mode = I2C_PCA_MODE_TURBO; + min_tlow = 14; + min_thi = 5; + raise_fall_time = 22; /* Raise 11e-8s, Fall 11e-8s */ + } else if (pca_data->i2c_clock > I2C_MAX_FAST_MODE_FREQ) { + mode = I2C_PCA_MODE_FASTP; + min_tlow = 17; + min_thi = 9; + raise_fall_time = 22; /* Raise 11e-8s, Fall 11e-8s */ + } else if (pca_data->i2c_clock > I2C_MAX_STANDARD_MODE_FREQ) { + mode = I2C_PCA_MODE_FAST; + min_tlow = 44; + min_thi = 20; + raise_fall_time = 58; /* Raise 29e-8s, Fall 29e-8s */ + } else { + mode = I2C_PCA_MODE_STD; + min_tlow = 157; + min_thi = 134; + raise_fall_time = 127; /* Raise 29e-8s, Fall 98e-8s */ + } + + /* The minimum clock that respects the thi/tlow = 134/157 is + * 64800 Hz. Below that, we have to fix the tlow to 255 and + * calculate the thi factor. + */ + if (clock < 648) { + tlow = 255; + thi = 1000000 - clock * raise_fall_time; + thi /= (I2C_PCA_OSC_PER * clock) - tlow; + } else { + tlow = (1000000 - clock * raise_fall_time) * min_tlow; + tlow /= I2C_PCA_OSC_PER * clock * (min_thi + min_tlow); + thi = tlow * min_thi / min_tlow; + } + + /* Store settings as these will be needed when the PCA chip is reset */ + pca_data->bus_settings.mode = mode; + pca_data->bus_settings.tlow = tlow; + pca_data->bus_settings.thi = thi; + + pca_reset(pca_data); + + printk(KERN_INFO + "%s: Clock frequency is %dHz\n", adap->name, clock * 100); + } + udelay(500); /* 500 us for oscillator to stabilise */ + + return 0; +} + +/* + * registering functions to load algorithms at runtime + */ +int i2c_pca_add_bus(struct i2c_adapter *adap) +{ + int rval; + + rval = pca_init(adap); + if (rval) + return rval; + + return i2c_add_adapter(adap); +} +EXPORT_SYMBOL(i2c_pca_add_bus); + +int i2c_pca_add_numbered_bus(struct i2c_adapter *adap) +{ + int rval; + + rval = pca_init(adap); + if (rval) + return rval; + + return i2c_add_numbered_adapter(adap); +} +EXPORT_SYMBOL(i2c_pca_add_numbered_bus); + +MODULE_AUTHOR("Ian Campbell <icampbell@arcom.com>"); +MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>"); +MODULE_DESCRIPTION("I2C-Bus PCA9564/PCA9665 algorithm"); +MODULE_LICENSE("GPL"); + +module_param(i2c_debug, int, 0); diff --git a/drivers/i2c/algos/i2c-algo-pcf.c b/drivers/i2c/algos/i2c-algo-pcf.c new file mode 100644 index 000000000..7a01f2687 --- /dev/null +++ b/drivers/i2c/algos/i2c-algo-pcf.c @@ -0,0 +1,423 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * i2c-algo-pcf.c i2c driver algorithms for PCF8584 adapters + * + * Copyright (C) 1995-1997 Simon G. Vogl + * 1998-2000 Hans Berglund + * + * With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and + * Frodo Looijaard <frodol@dds.nl>, and also from Martin Bailey + * <mbailey@littlefeet-inc.com> + * + * Partially rewriten by Oleg I. Vdovikin <vdovikin@jscc.ru> to handle multiple + * messages, proper stop/repstart signaling during receive, added detect code + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/i2c-algo-pcf.h> +#include "i2c-algo-pcf.h" + + +#define DEB2(x) if (i2c_debug >= 2) x +#define DEB3(x) if (i2c_debug >= 3) x /* print several statistical values */ +#define DEBPROTO(x) if (i2c_debug >= 9) x; + /* debug the protocol by showing transferred bits */ +#define DEF_TIMEOUT 16 + +/* + * module parameters: + */ +static int i2c_debug; + +/* setting states on the bus with the right timing: */ + +#define set_pcf(adap, ctl, val) adap->setpcf(adap->data, ctl, val) +#define get_pcf(adap, ctl) adap->getpcf(adap->data, ctl) +#define get_own(adap) adap->getown(adap->data) +#define get_clock(adap) adap->getclock(adap->data) +#define i2c_outb(adap, val) adap->setpcf(adap->data, 0, val) +#define i2c_inb(adap) adap->getpcf(adap->data, 0) + +/* other auxiliary functions */ + +static void i2c_start(struct i2c_algo_pcf_data *adap) +{ + DEBPROTO(printk(KERN_DEBUG "S ")); + set_pcf(adap, 1, I2C_PCF_START); +} + +static void i2c_repstart(struct i2c_algo_pcf_data *adap) +{ + DEBPROTO(printk(" Sr ")); + set_pcf(adap, 1, I2C_PCF_REPSTART); +} + +static void i2c_stop(struct i2c_algo_pcf_data *adap) +{ + DEBPROTO(printk("P\n")); + set_pcf(adap, 1, I2C_PCF_STOP); +} + +static void handle_lab(struct i2c_algo_pcf_data *adap, const int *status) +{ + DEB2(printk(KERN_INFO + "i2c-algo-pcf.o: lost arbitration (CSR 0x%02x)\n", + *status)); + /* + * Cleanup from LAB -- reset and enable ESO. + * This resets the PCF8584; since we've lost the bus, no + * further attempts should be made by callers to clean up + * (no i2c_stop() etc.) + */ + set_pcf(adap, 1, I2C_PCF_PIN); + set_pcf(adap, 1, I2C_PCF_ESO); + /* + * We pause for a time period sufficient for any running + * I2C transaction to complete -- the arbitration logic won't + * work properly until the next START is seen. + * It is assumed the bus driver or client has set a proper value. + * + * REVISIT: should probably use msleep instead of mdelay if we + * know we can sleep. + */ + if (adap->lab_mdelay) + mdelay(adap->lab_mdelay); + + DEB2(printk(KERN_INFO + "i2c-algo-pcf.o: reset LAB condition (CSR 0x%02x)\n", + get_pcf(adap, 1))); +} + +static int wait_for_bb(struct i2c_algo_pcf_data *adap) +{ + + int timeout = DEF_TIMEOUT; + int status; + + status = get_pcf(adap, 1); + + while (!(status & I2C_PCF_BB) && --timeout) { + udelay(100); /* wait for 100 us */ + status = get_pcf(adap, 1); + } + + if (timeout == 0) { + printk(KERN_ERR "Timeout waiting for Bus Busy\n"); + return -ETIMEDOUT; + } + + return 0; +} + +static int wait_for_pin(struct i2c_algo_pcf_data *adap, int *status) +{ + + int timeout = DEF_TIMEOUT; + + *status = get_pcf(adap, 1); + + while ((*status & I2C_PCF_PIN) && --timeout) { + adap->waitforpin(adap->data); + *status = get_pcf(adap, 1); + } + if (*status & I2C_PCF_LAB) { + handle_lab(adap, status); + return -EINTR; + } + + if (timeout == 0) + return -ETIMEDOUT; + + return 0; +} + +/* + * This should perform the 'PCF8584 initialization sequence' as described + * in the Philips IC12 data book (1995, Aug 29). + * There should be a 30 clock cycle wait after reset, I assume this + * has been fulfilled. + * There should be a delay at the end equal to the longest I2C message + * to synchronize the BB-bit (in multimaster systems). How long is + * this? I assume 1 second is always long enough. + * + * vdovikin: added detect code for PCF8584 + */ +static int pcf_init_8584 (struct i2c_algo_pcf_data *adap) +{ + unsigned char temp; + + DEB3(printk(KERN_DEBUG "i2c-algo-pcf.o: PCF state 0x%02x\n", + get_pcf(adap, 1))); + + /* S1=0x80: S0 selected, serial interface off */ + set_pcf(adap, 1, I2C_PCF_PIN); + /* + * check to see S1 now used as R/W ctrl - + * PCF8584 does that when ESO is zero + */ + if (((temp = get_pcf(adap, 1)) & 0x7f) != (0)) { + DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S0 (0x%02x).\n", temp)); + return -ENXIO; /* definitely not PCF8584 */ + } + + /* load own address in S0, effective address is (own << 1) */ + i2c_outb(adap, get_own(adap)); + /* check it's really written */ + if ((temp = i2c_inb(adap)) != get_own(adap)) { + DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't set S0 (0x%02x).\n", temp)); + return -ENXIO; + } + + /* S1=0xA0, next byte in S2 */ + set_pcf(adap, 1, I2C_PCF_PIN | I2C_PCF_ES1); + /* check to see S2 now selected */ + if (((temp = get_pcf(adap, 1)) & 0x7f) != I2C_PCF_ES1) { + DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S2 (0x%02x).\n", temp)); + return -ENXIO; + } + + /* load clock register S2 */ + i2c_outb(adap, get_clock(adap)); + /* check it's really written, the only 5 lowest bits does matter */ + if (((temp = i2c_inb(adap)) & 0x1f) != get_clock(adap)) { + DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't set S2 (0x%02x).\n", temp)); + return -ENXIO; + } + + /* Enable serial interface, idle, S0 selected */ + set_pcf(adap, 1, I2C_PCF_IDLE); + + /* check to see PCF is really idled and we can access status register */ + if ((temp = get_pcf(adap, 1)) != (I2C_PCF_PIN | I2C_PCF_BB)) { + DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S1` (0x%02x).\n", temp)); + return -ENXIO; + } + + printk(KERN_DEBUG "i2c-algo-pcf.o: detected and initialized PCF8584.\n"); + + return 0; +} + +static int pcf_sendbytes(struct i2c_adapter *i2c_adap, const char *buf, + int count, int last) +{ + struct i2c_algo_pcf_data *adap = i2c_adap->algo_data; + int wrcount, status, timeout; + + for (wrcount=0; wrcount<count; ++wrcount) { + DEB2(dev_dbg(&i2c_adap->dev, "i2c_write: writing %2.2X\n", + buf[wrcount] & 0xff)); + i2c_outb(adap, buf[wrcount]); + timeout = wait_for_pin(adap, &status); + if (timeout) { + if (timeout == -EINTR) + return -EINTR; /* arbitration lost */ + + i2c_stop(adap); + dev_err(&i2c_adap->dev, "i2c_write: error - timeout.\n"); + return -EREMOTEIO; /* got a better one ?? */ + } + if (status & I2C_PCF_LRB) { + i2c_stop(adap); + dev_err(&i2c_adap->dev, "i2c_write: error - no ack.\n"); + return -EREMOTEIO; /* got a better one ?? */ + } + } + if (last) + i2c_stop(adap); + else + i2c_repstart(adap); + + return wrcount; +} + +static int pcf_readbytes(struct i2c_adapter *i2c_adap, char *buf, + int count, int last) +{ + int i, status; + struct i2c_algo_pcf_data *adap = i2c_adap->algo_data; + int wfp; + + /* increment number of bytes to read by one -- read dummy byte */ + for (i = 0; i <= count; i++) { + + if ((wfp = wait_for_pin(adap, &status))) { + if (wfp == -EINTR) + return -EINTR; /* arbitration lost */ + + i2c_stop(adap); + dev_err(&i2c_adap->dev, "pcf_readbytes timed out.\n"); + return -1; + } + + if ((status & I2C_PCF_LRB) && (i != count)) { + i2c_stop(adap); + dev_err(&i2c_adap->dev, "i2c_read: i2c_inb, No ack.\n"); + return -1; + } + + if (i == count - 1) { + set_pcf(adap, 1, I2C_PCF_ESO); + } else if (i == count) { + if (last) + i2c_stop(adap); + else + i2c_repstart(adap); + } + + if (i) + buf[i - 1] = i2c_inb(adap); + else + i2c_inb(adap); /* dummy read */ + } + + return i - 1; +} + + +static int pcf_doAddress(struct i2c_algo_pcf_data *adap, + struct i2c_msg *msg) +{ + unsigned char addr = i2c_8bit_addr_from_msg(msg); + + if (msg->flags & I2C_M_REV_DIR_ADDR) + addr ^= 1; + i2c_outb(adap, addr); + + return 0; +} + +static int pcf_xfer(struct i2c_adapter *i2c_adap, + struct i2c_msg *msgs, + int num) +{ + struct i2c_algo_pcf_data *adap = i2c_adap->algo_data; + struct i2c_msg *pmsg; + int i; + int ret=0, timeout, status; + + if (adap->xfer_begin) + adap->xfer_begin(adap->data); + + /* Check for bus busy */ + timeout = wait_for_bb(adap); + if (timeout) { + DEB2(printk(KERN_ERR "i2c-algo-pcf.o: " + "Timeout waiting for BB in pcf_xfer\n");) + i = -EIO; + goto out; + } + + for (i = 0;ret >= 0 && i < num; i++) { + pmsg = &msgs[i]; + + DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: Doing %s %d bytes to 0x%02x - %d of %d messages\n", + pmsg->flags & I2C_M_RD ? "read" : "write", + pmsg->len, pmsg->addr, i + 1, num);) + + ret = pcf_doAddress(adap, pmsg); + + /* Send START */ + if (i == 0) + i2c_start(adap); + + /* Wait for PIN (pending interrupt NOT) */ + timeout = wait_for_pin(adap, &status); + if (timeout) { + if (timeout == -EINTR) { + /* arbitration lost */ + i = -EINTR; + goto out; + } + i2c_stop(adap); + DEB2(printk(KERN_ERR "i2c-algo-pcf.o: Timeout waiting " + "for PIN(1) in pcf_xfer\n");) + i = -EREMOTEIO; + goto out; + } + + /* Check LRB (last rcvd bit - slave ack) */ + if (status & I2C_PCF_LRB) { + i2c_stop(adap); + DEB2(printk(KERN_ERR "i2c-algo-pcf.o: No LRB(1) in pcf_xfer\n");) + i = -EREMOTEIO; + goto out; + } + + DEB3(printk(KERN_DEBUG "i2c-algo-pcf.o: Msg %d, addr=0x%x, flags=0x%x, len=%d\n", + i, msgs[i].addr, msgs[i].flags, msgs[i].len);) + + if (pmsg->flags & I2C_M_RD) { + ret = pcf_readbytes(i2c_adap, pmsg->buf, pmsg->len, + (i + 1 == num)); + + if (ret != pmsg->len) { + DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: fail: " + "only read %d bytes.\n",ret)); + } else { + DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: read %d bytes.\n",ret)); + } + } else { + ret = pcf_sendbytes(i2c_adap, pmsg->buf, pmsg->len, + (i + 1 == num)); + + if (ret != pmsg->len) { + DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: fail: " + "only wrote %d bytes.\n",ret)); + } else { + DEB2(printk(KERN_DEBUG "i2c-algo-pcf.o: wrote %d bytes.\n",ret)); + } + } + } + +out: + if (adap->xfer_end) + adap->xfer_end(adap->data); + return i; +} + +static u32 pcf_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | + I2C_FUNC_PROTOCOL_MANGLING; +} + +/* exported algorithm data: */ +static const struct i2c_algorithm pcf_algo = { + .master_xfer = pcf_xfer, + .functionality = pcf_func, +}; + +/* + * registering functions to load algorithms at runtime + */ +int i2c_pcf_add_bus(struct i2c_adapter *adap) +{ + struct i2c_algo_pcf_data *pcf_adap = adap->algo_data; + int rval; + + DEB2(dev_dbg(&adap->dev, "hw routines registered.\n")); + + /* register new adapter to i2c module... */ + adap->algo = &pcf_algo; + + if ((rval = pcf_init_8584(pcf_adap))) + return rval; + + rval = i2c_add_adapter(adap); + + return rval; +} +EXPORT_SYMBOL(i2c_pcf_add_bus); + +MODULE_AUTHOR("Hans Berglund <hb@spacetec.no>"); +MODULE_DESCRIPTION("I2C-Bus PCF8584 algorithm"); +MODULE_LICENSE("GPL"); + +module_param(i2c_debug, int, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(i2c_debug, + "debug level - 0 off; 1 normal; 2,3 more verbose; 9 pcf-protocol"); diff --git a/drivers/i2c/algos/i2c-algo-pcf.h b/drivers/i2c/algos/i2c-algo-pcf.h new file mode 100644 index 000000000..2448ab192 --- /dev/null +++ b/drivers/i2c/algos/i2c-algo-pcf.h @@ -0,0 +1,65 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* -------------------------------------------------------------------- */ +/* i2c-pcf8584.h: PCF 8584 global defines */ +/* -------------------------------------------------------------------- */ +/* Copyright (C) 1996 Simon G. Vogl + 1999 Hans Berglund + + */ +/* -------------------------------------------------------------------- */ + +/* With some changes from Frodo Looijaard <frodol@dds.nl> */ + +#ifndef I2C_PCF8584_H +#define I2C_PCF8584_H 1 + +/* ----- Control register bits ---------------------------------------- */ +#define I2C_PCF_PIN 0x80 +#define I2C_PCF_ESO 0x40 +#define I2C_PCF_ES1 0x20 +#define I2C_PCF_ES2 0x10 +#define I2C_PCF_ENI 0x08 +#define I2C_PCF_STA 0x04 +#define I2C_PCF_STO 0x02 +#define I2C_PCF_ACK 0x01 + +#define I2C_PCF_START (I2C_PCF_PIN | I2C_PCF_ESO | I2C_PCF_STA | I2C_PCF_ACK) +#define I2C_PCF_STOP (I2C_PCF_PIN | I2C_PCF_ESO | I2C_PCF_STO | I2C_PCF_ACK) +#define I2C_PCF_REPSTART ( I2C_PCF_ESO | I2C_PCF_STA | I2C_PCF_ACK) +#define I2C_PCF_IDLE (I2C_PCF_PIN | I2C_PCF_ESO | I2C_PCF_ACK) + +/* ----- Status register bits ----------------------------------------- */ +/*#define I2C_PCF_PIN 0x80 as above*/ + +#define I2C_PCF_INI 0x40 /* 1 if not initialized */ +#define I2C_PCF_STS 0x20 +#define I2C_PCF_BER 0x10 +#define I2C_PCF_AD0 0x08 +#define I2C_PCF_LRB 0x08 +#define I2C_PCF_AAS 0x04 +#define I2C_PCF_LAB 0x02 +#define I2C_PCF_BB 0x01 + +/* ----- Chip clock frequencies --------------------------------------- */ +#define I2C_PCF_CLK3 0x00 +#define I2C_PCF_CLK443 0x10 +#define I2C_PCF_CLK6 0x14 +#define I2C_PCF_CLK 0x18 +#define I2C_PCF_CLK12 0x1c + +/* ----- transmission frequencies ------------------------------------- */ +#define I2C_PCF_TRNS90 0x00 /* 90 kHz */ +#define I2C_PCF_TRNS45 0x01 /* 45 kHz */ +#define I2C_PCF_TRNS11 0x02 /* 11 kHz */ +#define I2C_PCF_TRNS15 0x03 /* 1.5 kHz */ + + +/* ----- Access to internal registers according to ES1,ES2 ------------ */ +/* they are mapped to the data port ( a0 = 0 ) */ +/* available when ESO == 0 : */ + +#define I2C_PCF_OWNADR 0 +#define I2C_PCF_INTREG I2C_PCF_ES2 +#define I2C_PCF_CLKREG I2C_PCF_ES1 + +#endif /* I2C_PCF8584_H */ diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig new file mode 100644 index 000000000..97d27e01a --- /dev/null +++ b/drivers/i2c/busses/Kconfig @@ -0,0 +1,1482 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Sensor device configuration +# + +menu "I2C Hardware Bus support" + depends on HAS_IOMEM + +comment "PC SMBus host controller drivers" + depends on PCI + +config I2C_CCGX_UCSI + tristate + help + A common module to provide an API to instantiate UCSI device + for Cypress CCGx Type-C controller. Individual bus drivers + need to select this one on demand. + +config I2C_ALI1535 + tristate "ALI 1535" + depends on PCI + help + If you say yes to this option, support will be included for the SMB + Host controller on Acer Labs Inc. (ALI) M1535 South Bridges. The SMB + controller is part of the 7101 device, which is an ACPI-compliant + Power Management Unit (PMU). + + This driver can also be built as a module. If so, the module + will be called i2c-ali1535. + +config I2C_ALI1563 + tristate "ALI 1563" + depends on PCI + help + If you say yes to this option, support will be included for the SMB + Host controller on Acer Labs Inc. (ALI) M1563 South Bridges. The SMB + controller is part of the 7101 device, which is an ACPI-compliant + Power Management Unit (PMU). + + This driver can also be built as a module. If so, the module + will be called i2c-ali1563. + +config I2C_ALI15X3 + tristate "ALI 15x3" + depends on PCI + help + If you say yes to this option, support will be included for the + Acer Labs Inc. (ALI) M1514 and M1543 motherboard I2C interfaces. + + This driver can also be built as a module. If so, the module + will be called i2c-ali15x3. + +config I2C_AMD756 + tristate "AMD 756/766/768/8111 and nVidia nForce" + depends on PCI + help + If you say yes to this option, support will be included for the AMD + 756/766/768 mainboard I2C interfaces. The driver also includes + support for the first (SMBus 1.0) I2C interface of the AMD 8111 and + the nVidia nForce I2C interface. + + This driver can also be built as a module. If so, the module + will be called i2c-amd756. + +config I2C_AMD756_S4882 + tristate "SMBus multiplexing on the Tyan S4882" + depends on I2C_AMD756 && X86 + help + Enabling this option will add specific SMBus support for the Tyan + S4882 motherboard. On this 4-CPU board, the SMBus is multiplexed + over 8 different channels, where the various memory module EEPROMs + and temperature sensors live. Saying yes here will give you access + to these in addition to the trunk. + + This driver can also be built as a module. If so, the module + will be called i2c-amd756-s4882. + +config I2C_AMD8111 + tristate "AMD 8111" + depends on PCI + help + If you say yes to this option, support will be included for the + second (SMBus 2.0) AMD 8111 mainboard I2C interface. + + This driver can also be built as a module. If so, the module + will be called i2c-amd8111. + +config I2C_AMD_MP2 + tristate "AMD MP2 PCIe" + depends on PCI && ACPI + help + If you say yes to this option, support will be included for the AMD + MP2 PCIe I2C adapter. + + This driver can also be built as modules. If so, the modules will + be called i2c-amd-mp2-pci and i2c-amd-mp2-plat. + +config I2C_HIX5HD2 + tristate "Hix5hd2 high-speed I2C driver" + depends on ARCH_HISI || ARCH_HIX5HD2 || COMPILE_TEST + help + Say Y here to include support for the high-speed I2C controller + used in HiSilicon hix5hd2 SoCs. + + This driver can also be built as a module. If so, the module + will be called i2c-hix5hd2. + +config I2C_I801 + tristate "Intel 82801 (ICH/PCH)" + depends on PCI + select P2SB if X86 + select CHECK_SIGNATURE if X86 && DMI + select I2C_SMBUS + help + If you say yes to this option, support will be included for the Intel + 801 family of mainboard I2C interfaces. Specifically, the following + versions of the chipset are supported: + 82801AA + 82801AB + 82801BA + 82801CA/CAM + 82801DB + 82801EB/ER (ICH5/ICH5R) + 6300ESB + ICH6 + ICH7 + ESB2 + ICH8 + ICH9 + EP80579 (Tolapai) + ICH10 + 5/3400 Series (PCH) + 6 Series (PCH) + Patsburg (PCH) + DH89xxCC (PCH) + Panther Point (PCH) + Lynx Point (PCH) + Avoton (SOC) + Wellsburg (PCH) + Coleto Creek (PCH) + Wildcat Point (PCH) + BayTrail (SOC) + Braswell (SOC) + Sunrise Point (PCH) + Kaby Lake (PCH) + DNV (SOC) + Broxton (SOC) + Lewisburg (PCH) + Gemini Lake (SOC) + Cannon Lake (PCH) + Cedar Fork (PCH) + Ice Lake (PCH) + Comet Lake (PCH) + Elkhart Lake (PCH) + Tiger Lake (PCH) + Jasper Lake (SOC) + Emmitsburg (PCH) + Alder Lake (PCH) + Raptor Lake (PCH) + Meteor Lake (SOC and PCH) + Birch Stream (SOC) + + This driver can also be built as a module. If so, the module + will be called i2c-i801. + +config I2C_ISCH + tristate "Intel SCH SMBus 1.0" + depends on PCI + select LPC_SCH + help + Say Y here if you want to use SMBus controller on the Intel SCH + based systems. + + This driver can also be built as a module. If so, the module + will be called i2c-isch. + +config I2C_ISMT + tristate "Intel iSMT SMBus Controller" + depends on PCI && X86 + help + If you say yes to this option, support will be included for the Intel + iSMT SMBus host controller interface. + + This driver can also be built as a module. If so, the module will be + called i2c-ismt. + +config I2C_PIIX4 + tristate "Intel PIIX4 and compatible (ATI/AMD/Serverworks/Broadcom/SMSC)" + depends on PCI + help + If you say yes to this option, support will be included for the Intel + PIIX4 family of mainboard I2C interfaces. Specifically, the following + versions of the chipset are supported (note that Serverworks is part + of Broadcom): + Intel PIIX4 + Intel 440MX + ATI IXP200 + ATI IXP300 + ATI IXP400 + ATI SB600 + ATI SB700/SP5100 + ATI SB800 + AMD Hudson-2 + AMD ML + AMD CZ + Hygon CZ + Serverworks OSB4 + Serverworks CSB5 + Serverworks CSB6 + Serverworks HT-1000 + Serverworks HT-1100 + SMSC Victory66 + + Some AMD chipsets contain two PIIX4-compatible SMBus + controllers. This driver will attempt to use both controllers + on the SB700/SP5100, if they have been initialized by the BIOS. + + This driver can also be built as a module. If so, the module + will be called i2c-piix4. + +config I2C_CHT_WC + tristate "Intel Cherry Trail Whiskey Cove PMIC smbus controller" + depends on INTEL_SOC_PMIC_CHTWC + help + If you say yes to this option, support will be included for the + SMBus controller found in the Intel Cherry Trail Whiskey Cove PMIC + found on some Intel Cherry Trail systems. + + Note this controller is hooked up to a TI bq24292i charger-IC, + combined with a FUSB302 Type-C port-controller as such it is advised + to also select CONFIG_TYPEC_FUSB302=m. + +config I2C_NFORCE2 + tristate "Nvidia nForce2, nForce3 and nForce4" + depends on PCI + help + If you say yes to this option, support will be included for the Nvidia + nForce2, nForce3 and nForce4 families of mainboard I2C interfaces. + + This driver can also be built as a module. If so, the module + will be called i2c-nforce2. + +config I2C_NFORCE2_S4985 + tristate "SMBus multiplexing on the Tyan S4985" + depends on I2C_NFORCE2 && X86 + help + Enabling this option will add specific SMBus support for the Tyan + S4985 motherboard. On this 4-CPU board, the SMBus is multiplexed + over 4 different channels, where the various memory module EEPROMs + live. Saying yes here will give you access to these in addition + to the trunk. + + This driver can also be built as a module. If so, the module + will be called i2c-nforce2-s4985. + +config I2C_NVIDIA_GPU + tristate "NVIDIA GPU I2C controller" + depends on PCI + select I2C_CCGX_UCSI + help + If you say yes to this option, support will be included for the + NVIDIA GPU I2C controller which is used to communicate with the GPU's + Type-C controller. This driver can also be built as a module called + i2c-nvidia-gpu. + +config I2C_SIS5595 + tristate "SiS 5595" + depends on PCI + help + If you say yes to this option, support will be included for the + SiS5595 SMBus (a subset of I2C) interface. + + This driver can also be built as a module. If so, the module + will be called i2c-sis5595. + +config I2C_SIS630 + tristate "SiS 630/730/964" + depends on PCI + help + If you say yes to this option, support will be included for the + SiS630, SiS730 and SiS964 SMBus (a subset of I2C) interface. + + This driver can also be built as a module. If so, the module + will be called i2c-sis630. + +config I2C_SIS96X + tristate "SiS 96x" + depends on PCI + help + If you say yes to this option, support will be included for the SiS + 96x SMBus (a subset of I2C) interfaces. Specifically, the following + chipsets are supported: + 645/961 + 645DX/961 + 645DX/962 + 648/961 + 650/961 + 735 + 745 + + This driver can also be built as a module. If so, the module + will be called i2c-sis96x. + +config I2C_VIA + tristate "VIA VT82C586B" + depends on PCI + select I2C_ALGOBIT + help + If you say yes to this option, support will be included for the VIA + 82C586B I2C interface + + This driver can also be built as a module. If so, the module + will be called i2c-via. + +config I2C_VIAPRO + tristate "VIA VT82C596/82C686/82xx and CX700/VX8xx/VX900" + depends on PCI + help + If you say yes to this option, support will be included for the VIA + VT82C596 and later SMBus interface. Specifically, the following + chipsets are supported: + VT82C596A/B + VT82C686A/B + VT8231 + VT8233/A + VT8235 + VT8237R/A/S + VT8251 + CX700 + VX800/VX820 + VX855/VX875 + VX900 + + This driver can also be built as a module. If so, the module + will be called i2c-viapro. + +if ACPI + +comment "ACPI drivers" + +config I2C_SCMI + tristate "SMBus Control Method Interface" + help + This driver supports the SMBus Control Method Interface. It needs the + BIOS to declare ACPI control methods as described in the SMBus Control + Method Interface specification. + + To compile this driver as a module, choose M here: + the module will be called i2c-scmi. + +endif # ACPI + +comment "Mac SMBus host controller drivers" + depends on PPC_CHRP || PPC_PMAC + +config I2C_HYDRA + tristate "CHRP Apple Hydra Mac I/O I2C interface" + depends on PCI && PPC_CHRP + select I2C_ALGOBIT + help + This supports the use of the I2C interface in the Apple Hydra Mac + I/O chip on some CHRP machines (e.g. the LongTrail). Say Y if you + have such a machine. + + This support is also available as a module. If so, the module + will be called i2c-hydra. + +config I2C_POWERMAC + tristate "Powermac I2C interface" + depends on PPC_PMAC + default y + help + This exposes the various PowerMac i2c interfaces to the linux i2c + layer and to userland. It is used by various drivers on the PowerMac + platform, and should generally be enabled. + + This support is also available as a module. If so, the module + will be called i2c-powermac. + +comment "I2C system bus drivers (mostly embedded / system-on-chip)" + +config I2C_ALTERA + tristate "Altera Soft IP I2C" + depends on ARCH_INTEL_SOCFPGA || NIOS2 || COMPILE_TEST + depends on OF + help + If you say yes to this option, support will be included for the + Altera Soft IP I2C interfaces on SoCFPGA and Nios2 architectures. + + This driver can also be built as a module. If so, the module + will be called i2c-altera. + +config I2C_ASPEED + tristate "Aspeed I2C Controller" + depends on ARCH_ASPEED || COMPILE_TEST + help + If you say yes to this option, support will be included for the + Aspeed I2C controller. + + This driver can also be built as a module. If so, the module + will be called i2c-aspeed. + +config I2C_AT91 + tristate "Atmel AT91 I2C Two-Wire interface (TWI)" + depends on ARCH_AT91 || COMPILE_TEST + help + This supports the use of the I2C interface on Atmel AT91 + processors. + + A serious problem is that there is no documented way to issue + repeated START conditions for more than two messages, as needed + to support combined I2C messages. Use the i2c-gpio driver + unless your system can cope with this limitation. + + Caution! at91rm9200, at91sam9261, at91sam9260, at91sam9263 devices + don't have clock stretching in transmission mode. For that reason, + you can encounter underrun issues causing premature stop sendings if + the latency to fill the transmission register is too long. If you + are facing this situation, use the i2c-gpio driver. + +config I2C_AT91_SLAVE_EXPERIMENTAL + tristate "Microchip AT91 I2C experimental slave mode" + depends on I2C_AT91 + select I2C_SLAVE + help + If you say yes to this option, support for the slave mode will be + added. Caution: do not use it for production. This feature has not + been tested in a heavy way, help wanted. + There are known bugs: + - It can hang, on a SAMA5D4, after several transfers. + - There are some mismtaches with a SAMA5D4 as slave and a SAMA5D2 as + master. + +config I2C_AU1550 + tristate "Au1550/Au1200/Au1300 SMBus interface" + depends on MIPS_ALCHEMY + help + If you say yes to this option, support will be included for the + Au1550/Au1200/Au1300 SMBus interface. + + This driver can also be built as a module. If so, the module + will be called i2c-au1550. + +config I2C_AXXIA + tristate "Axxia I2C controller" + depends on ARCH_AXXIA || COMPILE_TEST + default ARCH_AXXIA + select I2C_SLAVE + help + Say yes if you want to support the I2C bus on Axxia platforms. + + Please note that this controller is limited to transfers of maximum + 255 bytes in length. Any attempt to to a larger transfer will return + an error. + +config I2C_BCM2835 + tristate "Broadcom BCM2835 I2C controller" + depends on ARCH_BCM2835 || ARCH_BRCMSTB || COMPILE_TEST + depends on COMMON_CLK + help + If you say yes to this option, support will be included for the + BCM2835 I2C controller. + + If you don't know what to do here, say N. + + This support is also available as a module. If so, the module + will be called i2c-bcm2835. + +config I2C_BCM_IPROC + tristate "Broadcom iProc I2C controller" + depends on ARCH_BCM_IPROC || COMPILE_TEST + default ARCH_BCM_IPROC + select I2C_SLAVE + help + If you say yes to this option, support will be included for the + Broadcom iProc I2C controller. + + If you don't know what to do here, say N. + +config I2C_BCM_KONA + tristate "BCM Kona I2C adapter" + depends on ARCH_BCM_MOBILE || COMPILE_TEST + default y if ARCH_BCM_MOBILE + help + If you say yes to this option, support will be included for the + I2C interface on the Broadcom Kona family of processors. + + If you do not need KONA I2C interface, say N. + +config I2C_BRCMSTB + tristate "BRCM Settop/DSL I2C controller" + depends on ARCH_BCM2835 || ARCH_BCMBCA || ARCH_BRCMSTB || \ + BMIPS_GENERIC || COMPILE_TEST + default y + help + If you say yes to this option, support will be included for the + I2C interface on the Broadcom Settop/DSL SoCs. + + If you do not need I2C interface, say N. + +config I2C_CADENCE + tristate "Cadence I2C Controller" + depends on ARCH_ZYNQ || ARM64 || XTENSA || COMPILE_TEST + help + Say yes here to select Cadence I2C Host Controller. This controller is + e.g. used by Xilinx Zynq. + +config I2C_CBUS_GPIO + tristate "CBUS I2C driver" + depends on GPIOLIB || COMPILE_TEST + help + Support for CBUS access using I2C API. Mostly relevant for Nokia + Internet Tablets (770, N800 and N810). + + This driver can also be built as a module. If so, the module + will be called i2c-cbus-gpio. + +config I2C_CPM + tristate "Freescale CPM1 or CPM2 (MPC8xx/826x)" + depends on CPM1 || CPM2 + help + This supports the use of the I2C interface on Freescale + processors with CPM1 or CPM2. + + This driver can also be built as a module. If so, the module + will be called i2c-cpm. + +config I2C_DAVINCI + tristate "DaVinci I2C driver" + depends on ARCH_DAVINCI || ARCH_KEYSTONE || COMPILE_TEST + help + Support for TI DaVinci I2C controller driver. + + This driver can also be built as a module. If so, the module + will be called i2c-davinci. + + Please note that this driver might be needed to bring up other + devices such as DaVinci NIC. + For details please see http://www.ti.com/davinci + +config I2C_DESIGNWARE_CORE + tristate + select REGMAP + +config I2C_DESIGNWARE_SLAVE + bool "Synopsys DesignWare Slave" + depends on I2C_DESIGNWARE_CORE + select I2C_SLAVE + help + If you say yes to this option, support will be included for the + Synopsys DesignWare I2C slave adapter. + + This is not a standalone module, this module compiles together with + i2c-designware-core. + +config I2C_DESIGNWARE_PLATFORM + tristate "Synopsys DesignWare Platform" + depends on (ACPI && COMMON_CLK) || !ACPI + select I2C_DESIGNWARE_CORE + select MFD_SYSCON if MIPS_BAIKAL_T1 + help + If you say yes to this option, support will be included for the + Synopsys DesignWare I2C adapter. + + This driver can also be built as a module. If so, the module + will be called i2c-designware-platform. + +config I2C_DESIGNWARE_AMDPSP + bool "AMD PSP I2C semaphore support" + depends on ACPI + depends on CRYPTO_DEV_SP_PSP + depends on PCI + depends on I2C_DESIGNWARE_PLATFORM + depends on (I2C_DESIGNWARE_PLATFORM=y && CRYPTO_DEV_CCP_DD=y) || \ + (I2C_DESIGNWARE_PLATFORM=m && CRYPTO_DEV_CCP_DD) + help + This driver enables managed host access to the selected I2C bus shared + between AMD CPU and AMD PSP. + + You should say Y if running on an AMD system equipped with the PSP. + +config I2C_DESIGNWARE_BAYTRAIL + bool "Intel Baytrail I2C semaphore support" + depends on ACPI + depends on I2C_DESIGNWARE_PLATFORM + depends on (I2C_DESIGNWARE_PLATFORM=m && IOSF_MBI) || \ + (I2C_DESIGNWARE_PLATFORM=y && IOSF_MBI=y) + help + This driver enables managed host access to the PMIC I2C bus on select + Intel BayTrail platforms using the X-Powers AXP288 PMIC. It allows + the host to request uninterrupted access to the PMIC's I2C bus from + the platform firmware controlling it. You should say Y if running on + a BayTrail system using the AXP288. + +config I2C_DESIGNWARE_PCI + tristate "Synopsys DesignWare PCI" + depends on PCI + select I2C_DESIGNWARE_CORE + select I2C_CCGX_UCSI + help + If you say yes to this option, support will be included for the + Synopsys DesignWare I2C adapter. Only master mode is supported. + + This driver can also be built as a module. If so, the module + will be called i2c-designware-pci. + +config I2C_DIGICOLOR + tristate "Conexant Digicolor I2C driver" + depends on ARCH_DIGICOLOR || COMPILE_TEST + help + Support for Conexant Digicolor SoCs (CX92755) I2C controller driver. + + This driver can also be built as a module. If so, the module + will be called i2c-digicolor. + +config I2C_EG20T + tristate "Intel EG20T PCH/LAPIS Semicon IOH(ML7213/ML7223/ML7831) I2C" + depends on PCI && (X86_32 || MIPS || COMPILE_TEST) + help + This driver is for PCH(Platform controller Hub) I2C of EG20T which + is an IOH(Input/Output Hub) for x86 embedded processor. + This driver can access PCH I2C bus device. + + This driver also can be used for LAPIS Semiconductor IOH(Input/ + Output Hub), ML7213, ML7223 and ML7831. + ML7213 IOH is for IVI(In-Vehicle Infotainment) use, ML7223 IOH is + for MP(Media Phone) use and ML7831 IOH is for general purpose use. + ML7213/ML7223/ML7831 is companion chip for Intel Atom E6xx series. + ML7213/ML7223/ML7831 is completely compatible for Intel EG20T PCH. + +config I2C_EMEV2 + tristate "EMMA Mobile series I2C adapter" + depends on HAVE_CLK + select I2C_SLAVE + help + If you say yes to this option, support will be included for the + I2C interface on the Renesas Electronics EM/EV family of processors. + +config I2C_EXYNOS5 + tristate "Exynos high-speed I2C driver" + depends on OF + depends on ARCH_EXYNOS || COMPILE_TEST + default y if ARCH_EXYNOS + help + High-speed I2C controller on Samsung Exynos5 and newer Samsung SoCs: + Exynos5250, Exynos5260, Exynos5410, Exynos542x, Exynos5800, + Exynos5433, Exynos7, Exynos850 and ExynosAutoV9. + Choose Y here only if you build for such Samsung SoC. + +config I2C_GPIO + tristate "GPIO-based bitbanging I2C" + depends on GPIOLIB || COMPILE_TEST + select I2C_ALGOBIT + help + This is a very simple bitbanging I2C driver utilizing the + arch-neutral GPIO API to control the SCL and SDA lines. + +config I2C_GPIO_FAULT_INJECTOR + bool "GPIO-based fault injector" + depends on I2C_GPIO + help + This adds some functionality to the i2c-gpio driver which can inject + faults to an I2C bus, so another bus master can be stress-tested. + This is for debugging. If unsure, say 'no'. + +config I2C_GXP + tristate "GXP I2C Interface" + depends on ARCH_HPE_GXP || COMPILE_TEST + help + This enables support for GXP I2C interface. The I2C engines can be + either I2C master or I2C slaves. + +config I2C_HIGHLANDER + tristate "Highlander FPGA SMBus interface" + depends on SH_HIGHLANDER || COMPILE_TEST + help + If you say yes to this option, support will be included for + the SMBus interface located in the FPGA on various Highlander + boards, particularly the R0P7780LC0011RL and R0P7785LC0011RL + FPGAs. This is wholly unrelated to the SoC I2C. + + This driver can also be built as a module. If so, the module + will be called i2c-highlander. + +config I2C_HISI + tristate "HiSilicon I2C controller" + depends on ARM64 || COMPILE_TEST + help + Say Y here if you want to have Hisilicon I2C controller support + available on the Kunpeng Server. + + This driver can also be built as a module. If so, the module + will be called i2c-hisi. + +config I2C_IBM_IIC + tristate "IBM PPC 4xx on-chip I2C interface" + depends on 4xx + help + Say Y here if you want to use IIC peripheral found on + embedded IBM PPC 4xx based systems. + + This driver can also be built as a module. If so, the module + will be called i2c-ibm_iic. + +config I2C_IMG + tristate "Imagination Technologies I2C SCB Controller" + depends on MIPS || COMPILE_TEST + help + Say Y here if you want to use the IMG I2C SCB controller, + available on the TZ1090 and other IMG SoCs. + + This driver can also be built as a module. If so, the module + will be called i2c-img-scb. + +config I2C_IMX + tristate "IMX I2C interface" + depends on ARCH_MXC || ARCH_LAYERSCAPE || COLDFIRE || COMPILE_TEST + select I2C_SLAVE + help + Say Y here if you want to use the IIC bus controller on + the Freescale i.MX/MXC, Layerscape or ColdFire processors. + + This driver can also be built as a module. If so, the module + will be called i2c-imx. + +config I2C_IMX_LPI2C + tristate "IMX Low Power I2C interface" + depends on ARCH_MXC || COMPILE_TEST + help + Say Y here if you want to use the Low Power IIC bus controller + on the Freescale i.MX processors. + + This driver can also be built as a module. If so, the module + will be called i2c-imx-lpi2c. + +config I2C_IOP3XX + tristate "Intel IXP4xx on-chip I2C interface" + depends on ARCH_IXP4XX || COMPILE_TEST + help + Say Y here if you want to use the IIC bus controller on + the Intel IXP4xx Network Processors. + + This driver can also be built as a module. If so, the module + will be called i2c-iop3xx. + +config I2C_JZ4780 + tristate "JZ4780 I2C controller interface support" + depends on MIPS || COMPILE_TEST + help + If you say yes to this option, support will be included for the + Ingenic JZ4780 I2C controller. + + If you don't know what to do here, say N. + +config I2C_KEMPLD + tristate "Kontron COM I2C Controller" + depends on MFD_KEMPLD + help + This enables support for the I2C bus interface on some Kontron ETX + and COMexpress (ETXexpress) modules. + + This driver can also be built as a module. If so, the module + will be called i2c-kempld. + +config I2C_LPC2K + tristate "I2C bus support for NXP LPC2K/LPC178x/18xx/43xx" + depends on OF && (ARCH_LPC18XX || COMPILE_TEST) + help + This driver supports the I2C interface found several NXP + devices including LPC2xxx, LPC178x/7x and LPC18xx/43xx. + + This driver can also be built as a module. If so, the module + will be called i2c-lpc2k. + +config I2C_LS2X + tristate "Loongson LS2X I2C adapter" + depends on MACH_LOONGSON64 || COMPILE_TEST + help + If you say yes to this option, support will be included for the + I2C interface on the Loongson-2K SoCs and Loongson LS7A bridge + chip. + + This driver can also be built as a module. If so, the module + will be called i2c-ls2x. + +config I2C_MLXBF + tristate "Mellanox BlueField I2C controller" + depends on MELLANOX_PLATFORM && ARM64 + depends on ACPI + select I2C_SLAVE + help + Enabling this option will add I2C SMBus support for Mellanox BlueField + system. + + This driver can also be built as a module. If so, the module will be + called i2c-mlxbf. + + This driver implements an I2C SMBus host controller and enables both + master and slave functions. + +config I2C_MESON + tristate "Amlogic Meson I2C controller" + depends on ARCH_MESON || COMPILE_TEST + depends on COMMON_CLK + help + If you say yes to this option, support will be included for the + I2C interface on the Amlogic Meson family of SoCs. + +config I2C_MICROCHIP_CORE + tristate "Microchip FPGA I2C controller" + depends on ARCH_MICROCHIP_POLARFIRE || COMPILE_TEST + depends on OF + help + If you say yes to this option, support will be included for the + I2C interface on Microchip FPGAs. + + This driver can also be built as a module. If so, the module will be + called i2c-microchip-core. + +config I2C_MPC + tristate "MPC107/824x/85xx/512x/52xx/83xx/86xx" + depends on PPC + help + If you say yes to this option, support will be included for the + built-in I2C interface on the MPC107, Tsi107, MPC512x, MPC52xx, + MPC8240, MPC8245, MPC83xx, MPC85xx and MPC8641 family processors. + + This driver can also be built as a module. If so, the module + will be called i2c-mpc. + +config I2C_MT65XX + tristate "MediaTek I2C adapter" + depends on ARCH_MEDIATEK || COMPILE_TEST + help + This selects the MediaTek(R) Integrated Inter Circuit bus driver + for MT65xx and MT81xx. + If you want to use MediaTek(R) I2C interface, say Y or M here. + If unsure, say N. + +config I2C_MT7621 + tristate "MT7621/MT7628 I2C Controller" + depends on (RALINK && (SOC_MT7620 || SOC_MT7621)) || COMPILE_TEST + help + Say Y here to include support for I2C controller in the + MediaTek MT7621/MT7628 SoCs. + +config I2C_MV64XXX + tristate "Marvell mv64xxx I2C Controller" + depends on PLAT_ORION || ARCH_SUNXI || ARCH_MVEBU || COMPILE_TEST + help + If you say yes to this option, support will be included for the + built-in I2C interface on the Marvell 64xxx line of host bridges. + This driver is also used for Allwinner SoCs I2C controllers. + + This driver can also be built as a module. If so, the module + will be called i2c-mv64xxx. + +config I2C_MXS + tristate "Freescale i.MX28 I2C interface" + depends on SOC_IMX28 || COMPILE_TEST + select STMP_DEVICE + help + Say Y here if you want to use the I2C bus controller on + the Freescale i.MX28 processors. + + This driver can also be built as a module. If so, the module + will be called i2c-mxs. + +config I2C_NOMADIK + tristate "ST-Ericsson Nomadik/Ux500 I2C Controller" + depends on ARM_AMBA + help + If you say yes to this option, support will be included for the + I2C interface from ST-Ericsson's Nomadik and Ux500 architectures, + as well as the STA2X11 PCIe I/O HUB. + +config I2C_NPCM + tristate "Nuvoton I2C Controller" + depends on ARCH_NPCM || COMPILE_TEST + help + If you say yes to this option, support will be included for the + Nuvoton I2C controller, which is available on the NPCM BMC + controllers. + Driver can also support slave mode (select I2C_SLAVE). + +config I2C_OCORES + tristate "OpenCores I2C Controller" + help + If you say yes to this option, support will be included for the + OpenCores I2C controller. For details see + http://www.opencores.org/projects.cgi/web/i2c/overview + + This driver can also be built as a module. If so, the module + will be called i2c-ocores. + +config I2C_OMAP + tristate "OMAP I2C adapter" + depends on ARCH_OMAP || ARCH_K3 || COMPILE_TEST + default MACH_OMAP_OSK + help + If you say yes to this option, support will be included for the + I2C interface on the Texas Instruments OMAP1/2 family of processors. + Like OMAP1510/1610/1710/5912 and OMAP242x. + For details see http://www.ti.com/omap. + +config I2C_OWL + tristate "Actions Semiconductor Owl I2C Controller" + depends on ARCH_ACTIONS || COMPILE_TEST + help + Say Y here if you want to use the I2C bus controller on + the Actions Semiconductor Owl SoC's. + +config I2C_PASEMI + tristate "PA Semi SMBus interface" + depends on PPC_PASEMI && PCI + help + Supports the PA Semi PWRficient on-chip SMBus interfaces. + +config I2C_APPLE + tristate "Apple SMBus platform driver" + depends on !I2C_PASEMI + depends on ARCH_APPLE || COMPILE_TEST + default ARCH_APPLE + help + Say Y here if you want to use the I2C controller present on Apple + Silicon chips such as the M1. + + This driver can also be built as a module. If so, the module + will be called i2c-apple. + +config I2C_PCA_PLATFORM + tristate "PCA9564/PCA9665 as platform device" + select I2C_ALGOPCA + help + This driver supports a memory mapped Philips PCA9564/PCA9665 + parallel bus to I2C bus controller. + + This driver can also be built as a module. If so, the module + will be called i2c-pca-platform. + +config I2C_PNX + tristate "I2C bus support for Philips PNX and NXP LPC targets" + depends on ARCH_LPC32XX || COMPILE_TEST + help + This driver supports the Philips IP3204 I2C IP block master and/or + slave controller + + This driver can also be built as a module. If so, the module + will be called i2c-pnx. + +config I2C_PXA + tristate "Intel PXA2XX I2C adapter" + depends on ARCH_PXA || ARCH_MMP || ARCH_MVEBU || (X86_32 && PCI && OF) || COMPILE_TEST + help + If you have devices in the PXA I2C bus, say yes to this option. + This driver can also be built as a module. If so, the module + will be called i2c-pxa. + +config I2C_PXA_PCI + def_bool I2C_PXA && X86_32 && PCI && OF + +config I2C_PXA_SLAVE + bool "Intel PXA2XX I2C Slave comms support" + depends on I2C_PXA && !X86_32 + select I2C_SLAVE + help + Support I2C slave mode communications on the PXA I2C bus. This + is necessary for systems where the PXA may be a target on the + I2C bus. + +config I2C_QCOM_CCI + tristate "Qualcomm Camera Control Interface" + depends on ARCH_QCOM || COMPILE_TEST + help + If you say yes to this option, support will be included for the + built-in camera control interface on the Qualcomm SoCs. + + This driver can also be built as a module. If so, the module + will be called i2c-qcom-cci. + +config I2C_QCOM_GENI + tristate "Qualcomm Technologies Inc.'s GENI based I2C controller" + depends on ARCH_QCOM || COMPILE_TEST + depends on QCOM_GENI_SE + help + This driver supports GENI serial engine based I2C controller in + master mode on the Qualcomm Technologies Inc.'s SoCs. If you say + yes to this option, support will be included for the built-in I2C + interface on the Qualcomm Technologies Inc.'s SoCs. + + This driver can also be built as a module. If so, the module + will be called i2c-qcom-geni. + +config I2C_QUP + tristate "Qualcomm QUP based I2C controller" + depends on ARCH_QCOM || COMPILE_TEST + help + If you say yes to this option, support will be included for the + built-in I2C interface on the Qualcomm SoCs. + + This driver can also be built as a module. If so, the module + will be called i2c-qup. + +config I2C_RIIC + tristate "Renesas RIIC adapter" + depends on ARCH_RENESAS || COMPILE_TEST + help + If you say yes to this option, support will be included for the + Renesas RIIC I2C interface. + + This driver can also be built as a module. If so, the module + will be called i2c-riic. + +config I2C_RK3X + tristate "Rockchip RK3xxx I2C adapter" + depends on OF && COMMON_CLK + help + Say Y here to include support for the I2C adapter in Rockchip RK3xxx + SoCs. + + This driver can also be built as a module. If so, the module will + be called i2c-rk3x. + +config I2C_RZV2M + tristate "Renesas RZ/V2M adapter" + depends on ARCH_RENESAS || COMPILE_TEST + help + If you say yes to this option, support will be included for the + Renesas RZ/V2M I2C interface. + + This driver can also be built as a module. If so, the module + will be called i2c-rzv2m. + +config I2C_S3C2410 + tristate "S3C/Exynos I2C Driver" + depends on ARCH_EXYNOS || ARCH_S3C64XX || ARCH_S5PV210 || COMPILE_TEST + help + Say Y here to include support for I2C controller in the + Samsung SoCs (S3C, S5Pv210, Exynos). + +config I2C_SH7760 + tristate "Renesas SH7760 I2C Controller" + depends on CPU_SUBTYPE_SH7760 + help + This driver supports the 2 I2C interfaces on the Renesas SH7760. + + This driver can also be built as a module. If so, the module + will be called i2c-sh7760. + +config I2C_SH_MOBILE + tristate "SuperH Mobile I2C Controller" + depends on ARCH_SHMOBILE || ARCH_RENESAS || COMPILE_TEST + help + If you say yes to this option, support will be included for the + built-in I2C interface on the Renesas SH-Mobile processor. + + This driver can also be built as a module. If so, the module + will be called i2c-sh_mobile. + +config I2C_SIMTEC + tristate "Simtec Generic I2C interface" + select I2C_ALGOBIT + help + If you say yes to this option, support will be included for + the Simtec Generic I2C interface. This driver is for the + simple I2C bus used on newer Simtec products for general + I2C, such as DDC on the Simtec BBD2016A. + + This driver can also be built as a module. If so, the module + will be called i2c-simtec. + +config I2C_SPRD + tristate "Spreadtrum I2C interface" + depends on I2C=y && (ARCH_SPRD || COMPILE_TEST) + depends on COMMON_CLK + help + If you say yes to this option, support will be included for the + Spreadtrum I2C interface. + +config I2C_ST + tristate "STMicroelectronics SSC I2C support" + depends on ARCH_STI || COMPILE_TEST + help + Enable this option to add support for STMicroelectronics SoCs + hardware SSC (Synchronous Serial Controller) as an I2C controller. + + This driver can also be built as module. If so, the module + will be called i2c-st. + +config I2C_STM32F4 + tristate "STMicroelectronics STM32F4 I2C support" + depends on ARCH_STM32 || COMPILE_TEST + help + Enable this option to add support for STM32 I2C controller embedded + in STM32F4 SoCs. + + This driver can also be built as module. If so, the module + will be called i2c-stm32f4. + +config I2C_STM32F7 + tristate "STMicroelectronics STM32F7 I2C support" + depends on ARCH_STM32 || COMPILE_TEST + select I2C_SLAVE + select I2C_SMBUS + help + Enable this option to add support for STM32 I2C controller embedded + in STM32F7 SoCs. + + This driver can also be built as module. If so, the module + will be called i2c-stm32f7. + +config I2C_SUN6I_P2WI + tristate "Allwinner sun6i internal P2WI controller" + depends on RESET_CONTROLLER + depends on MACH_SUN6I || COMPILE_TEST + help + If you say yes to this option, support will be included for the + P2WI (Push/Pull 2 Wire Interface) controller embedded in some sunxi + SOCs. + The P2WI looks like an SMBus controller (which supports only byte + accesses), except that it only supports one slave device. + This interface is used to connect to specific PMIC devices (like the + AXP221). + +config I2C_SYNQUACER + tristate "Socionext SynQuacer I2C controller" + depends on ARCH_SYNQUACER || COMPILE_TEST + help + Say Y here to include support for the I2C controller used in some + Fujitsu and Socionext SoCs. + + This driver can also be built as a module. If so, the module + will be called i2c-synquacer. + +config I2C_TEGRA + tristate "NVIDIA Tegra internal I2C controller" + depends on ARCH_TEGRA || (COMPILE_TEST && (ARC || ARM || ARM64 || M68K || RISCV || SUPERH || SPARC)) + # COMPILE_TEST needs architectures with readsX()/writesX() primitives + help + If you say yes to this option, support will be included for the + I2C controller embedded in NVIDIA Tegra SOCs + +config I2C_TEGRA_BPMP + tristate "NVIDIA Tegra BPMP I2C controller" + depends on TEGRA_BPMP || COMPILE_TEST + default y if TEGRA_BPMP + help + If you say yes to this option, support will be included for the I2C + controller embedded in NVIDIA Tegra SoCs accessed via the BPMP. + + This I2C driver is a 'virtual' I2C driver. The real driver is part + of the BPMP firmware, and this driver merely communicates with that + real driver. + +config I2C_UNIPHIER + tristate "UniPhier FIFO-less I2C controller" + depends on ARCH_UNIPHIER || COMPILE_TEST + help + If you say yes to this option, support will be included for + the UniPhier FIFO-less I2C interface embedded in PH1-LD4, PH1-sLD8, + or older UniPhier SoCs. + +config I2C_UNIPHIER_F + tristate "UniPhier FIFO-builtin I2C controller" + depends on ARCH_UNIPHIER || COMPILE_TEST + help + If you say yes to this option, support will be included for + the UniPhier FIFO-builtin I2C interface embedded in PH1-Pro4, + PH1-Pro5, or newer UniPhier SoCs. + +config I2C_VERSATILE + tristate "ARM Versatile/Realview I2C bus support" + depends on ARCH_MPS2 || ARCH_VERSATILE || ARCH_REALVIEW || ARCH_VEXPRESS || COMPILE_TEST + select I2C_ALGOBIT + help + Say yes if you want to support the I2C serial bus on ARMs Versatile + range of platforms. + + This driver can also be built as a module. If so, the module + will be called i2c-versatile. + +config I2C_WMT + tristate "Wondermedia WM8xxx SoC I2C bus support" + depends on ARCH_VT8500 || COMPILE_TEST + help + Say yes if you want to support the I2C bus on Wondermedia 8xxx-series + SoCs. + + This driver can also be built as a module. If so, the module will be + called i2c-wmt. + +config I2C_OCTEON + tristate "Cavium OCTEON I2C bus support" + depends on CAVIUM_OCTEON_SOC + help + Say yes if you want to support the I2C serial bus on Cavium + OCTEON SOC. + + This driver can also be built as a module. If so, the module + will be called i2c-octeon. + +config I2C_THUNDERX + tristate "Cavium ThunderX I2C bus support" + depends on 64BIT && PCI && (ARM64 || COMPILE_TEST) + select I2C_SMBUS + help + Say yes if you want to support the I2C serial bus on Cavium + ThunderX SOC. + + This driver can also be built as a module. If so, the module + will be called i2c-thunderx. + +config I2C_XILINX + tristate "Xilinx I2C Controller" + depends on HAS_IOMEM + help + If you say yes to this option, support will be included for the + Xilinx I2C controller. + + This driver can also be built as a module. If so, the module + will be called xilinx_i2c. + +config I2C_XLP9XX + tristate "Cavium ThunderX2 I2C support" + depends on ARCH_THUNDER2 || COMPILE_TEST + help + This driver enables support for the on-chip I2C interface of + the Cavium ThunderX2 processors. (Originally on Netlogic XLP SoCs.) + + This driver can also be built as a module. If so, the module will + be called i2c-xlp9xx. + +config I2C_RCAR + tristate "Renesas R-Car I2C Controller" + depends on ARCH_RENESAS || COMPILE_TEST + select I2C_SLAVE + select I2C_SMBUS + select RESET_CONTROLLER if ARCH_RCAR_GEN3 + help + If you say yes to this option, support will be included for the + R-Car I2C controller. + + This driver can also be built as a module. If so, the module + will be called i2c-rcar. + +comment "External I2C/SMBus adapter drivers" + +config I2C_DIOLAN_U2C + tristate "Diolan U2C-12 USB adapter" + depends on USB + help + If you say yes to this option, support will be included for Diolan + U2C-12, a USB to I2C interface. + + This driver can also be built as a module. If so, the module + will be called i2c-diolan-u2c. + +config I2C_DLN2 + tristate "Diolan DLN-2 USB I2C adapter" + depends on MFD_DLN2 + help + If you say yes to this option, support will be included for Diolan + DLN2, a USB to I2C interface. + + This driver can also be built as a module. If so, the module + will be called i2c-dln2. + +config I2C_CP2615 + tristate "Silicon Labs CP2615 USB sound card and I2C adapter" + depends on USB + help + If you say yes to this option, support will be included for Silicon + Labs CP2615's I2C interface. + + This driver can also be built as a module. If so, the module + will be called i2c-cp2615. + +config I2C_PARPORT + tristate "Parallel port adapter" + depends on PARPORT + select I2C_ALGOBIT + select I2C_SMBUS + help + This supports parallel port I2C adapters such as the ones made by + Philips or Velleman, Analog Devices evaluation boards, and more. + Basically any adapter using the parallel port as an I2C bus with + no extra chipset is supported by this driver, or could be. Please + read the file Documentation/i2c/busses/i2c-parport.rst for details. + + This support is also available as a module. If so, the module + will be called i2c-parport. + +config I2C_PCI1XXXX + tristate "PCI1XXXX I2C Host Adapter" + depends on PCI + help + If you say yes to this option, support will be included for + Microchip PCI1XXXX's I2C interface. + + This driver can also be built as a module. If so, the module will + be called i2c-mchp-pci1xxxx. + +config I2C_ROBOTFUZZ_OSIF + tristate "RobotFuzz Open Source InterFace USB adapter" + depends on USB + help + If you say yes to this option, support will be included for the + RobotFuzz Open Source InterFace USB to I2C interface. + + This driver can also be built as a module. If so, the module + will be called i2c-osif. + +config I2C_TAOS_EVM + tristate "TAOS evaluation module" + depends on TTY + select SERIO + select SERIO_SERPORT + help + This supports TAOS evaluation modules on serial port. In order to + use this driver, you will need the inputattach tool, which is part + of the input-utils package. + + If unsure, say N. + + This support is also available as a module. If so, the module + will be called i2c-taos-evm. + +config I2C_TINY_USB + tristate "Tiny-USB adapter" + depends on USB + help + If you say yes to this option, support will be included for the + i2c-tiny-usb, a simple do-it-yourself USB to I2C interface. See + http://www.harbaum.org/till/i2c_tiny_usb for hardware details. + + This driver can also be built as a module. If so, the module + will be called i2c-tiny-usb. + +config I2C_VIPERBOARD + tristate "Viperboard I2C master support" + depends on MFD_VIPERBOARD && USB + help + Say yes here to access the I2C part of the Nano River + Technologies Viperboard as I2C master. + See viperboard API specification and Nano + River Tech's viperboard.h for detailed meaning + of the module parameters. + +comment "Other I2C/SMBus bus drivers" + +config I2C_ACORN + tristate "Acorn IOC/IOMD I2C bus support" + depends on ARCH_ACORN + default y + select I2C_ALGOBIT + help + Say yes if you want to support the I2C bus on Acorn platforms. + + If you don't know, say Y. + +config I2C_ELEKTOR + tristate "Elektor ISA card" + depends on ISA && HAS_IOPORT_MAP && BROKEN_ON_SMP + select I2C_ALGOPCF + help + This supports the PCF8584 ISA bus I2C adapter. Say Y if you own + such an adapter. + + This support is also available as a module. If so, the module + will be called i2c-elektor. + +config I2C_ICY + tristate "ICY Zorro card" + depends on ZORRO + select I2C_ALGOPCF + help + This supports the PCF8584 Zorro bus I2C adapter, known as ICY. + Say Y if you own such an adapter. + + This support is also available as a module. If so, the module + will be called i2c-icy. + + If you have a 2019 edition board with an LTC2990 sensor at address + 0x4c, loading the module 'ltc2990' is sufficient to enable it. + +config I2C_MLXCPLD + tristate "Mellanox I2C driver" + depends on X86_64 || (ARM64 && ACPI) || COMPILE_TEST + help + This exposes the Mellanox platform I2C busses to the linux I2C layer + for X86 and ARM64/ACPI based systems. + Controller is implemented as CPLD logic. + + This driver can also be built as a module. If so, the module will be + called as i2c-mlxcpld. + +config I2C_PCA_ISA + tristate "PCA9564/PCA9665 on an ISA bus" + depends on ISA + select I2C_ALGOPCA + help + This driver supports ISA boards using the Philips PCA9564/PCA9665 + parallel bus to I2C bus controller. + + This driver can also be built as a module. If so, the module + will be called i2c-pca-isa. + + This device is almost undetectable and using this driver on a + system which doesn't have this device will result in long + delays when I2C/SMBus chip drivers are loaded (e.g. at boot + time). If unsure, say N. + +config I2C_SIBYTE + tristate "SiByte SMBus interface" + depends on SIBYTE_SB1xxx_SOC + help + Supports the SiByte SOC on-chip I2C interfaces (2 channels). + +config I2C_CROS_EC_TUNNEL + tristate "ChromeOS EC tunnel I2C bus" + depends on CROS_EC + help + If you say yes here you get an I2C bus that will tunnel i2c commands + through to the other side of the ChromeOS EC to the i2c bus + connected there. This will work whatever the interface used to + talk to the EC (SPI, I2C or LPC). + +config I2C_XGENE_SLIMPRO + tristate "APM X-Gene SoC I2C SLIMpro devices support" + depends on ARCH_XGENE && MAILBOX + help + Enable I2C bus access using the APM X-Gene SoC SLIMpro + co-processor. The I2C device access the I2C bus via the X-Gene + to SLIMpro (On chip coprocessor) mailbox mechanism. + If unsure, say N. + +config SCx200_ACB + tristate "Geode ACCESS.bus support" + depends on X86_32 && PCI + help + Enable the use of the ACCESS.bus controllers on the Geode SCx200 and + SC1100 processors and the CS5535 and CS5536 Geode companion devices. + + If you don't know what to do here, say N. + + This support is also available as a module. If so, the module + will be called scx200_acb. + +config I2C_OPAL + tristate "IBM OPAL I2C driver" + depends on PPC_POWERNV + default y + help + This exposes the PowerNV platform i2c busses to the linux i2c layer, + the driver is based on the OPAL interfaces. + + This driver can also be built as a module. If so, the module will be + called as i2c-opal. + +config I2C_FSI + tristate "FSI I2C driver" + depends on FSI + help + Driver for FSI bus attached I2C masters. These are I2C masters that + are connected to the system over an FSI bus, instead of the more + common PCI or MMIO interface. + + This driver can also be built as a module. If so, the module will be + called as i2c-fsi. + +config I2C_VIRTIO + tristate "Virtio I2C Adapter" + select VIRTIO + help + If you say yes to this option, support will be included for the virtio + I2C adapter driver. The hardware can be emulated by any device model + software according to the virtio protocol. + + This driver can also be built as a module. If so, the module + will be called i2c-virtio. + +endmenu diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile new file mode 100644 index 000000000..af56fe2c7 --- /dev/null +++ b/drivers/i2c/busses/Makefile @@ -0,0 +1,161 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for the i2c bus drivers. +# + +# ACPI drivers +obj-$(CONFIG_I2C_SCMI) += i2c-scmi.o + +# Auxiliary I2C/SMBus modules +obj-$(CONFIG_I2C_CCGX_UCSI) += i2c-ccgx-ucsi.o + +# PC SMBus host controller drivers +obj-$(CONFIG_I2C_ALI1535) += i2c-ali1535.o +obj-$(CONFIG_I2C_ALI1563) += i2c-ali1563.o +obj-$(CONFIG_I2C_ALI15X3) += i2c-ali15x3.o +obj-$(CONFIG_I2C_AMD756) += i2c-amd756.o +obj-$(CONFIG_I2C_AMD756_S4882) += i2c-amd756-s4882.o +obj-$(CONFIG_I2C_AMD8111) += i2c-amd8111.o +obj-$(CONFIG_I2C_CHT_WC) += i2c-cht-wc.o +obj-$(CONFIG_I2C_I801) += i2c-i801.o +obj-$(CONFIG_I2C_ISCH) += i2c-isch.o +obj-$(CONFIG_I2C_ISMT) += i2c-ismt.o +obj-$(CONFIG_I2C_NFORCE2) += i2c-nforce2.o +obj-$(CONFIG_I2C_NFORCE2_S4985) += i2c-nforce2-s4985.o +obj-$(CONFIG_I2C_NVIDIA_GPU) += i2c-nvidia-gpu.o +obj-$(CONFIG_I2C_PIIX4) += i2c-piix4.o +obj-$(CONFIG_I2C_SIS5595) += i2c-sis5595.o +obj-$(CONFIG_I2C_SIS630) += i2c-sis630.o +obj-$(CONFIG_I2C_SIS96X) += i2c-sis96x.o +obj-$(CONFIG_I2C_VIA) += i2c-via.o +obj-$(CONFIG_I2C_VIAPRO) += i2c-viapro.o + +# Mac SMBus host controller drivers +obj-$(CONFIG_I2C_HYDRA) += i2c-hydra.o +obj-$(CONFIG_I2C_POWERMAC) += i2c-powermac.o + +# Embedded system I2C/SMBus host controller drivers +obj-$(CONFIG_I2C_ALTERA) += i2c-altera.o +obj-$(CONFIG_I2C_AMD_MP2) += i2c-amd-mp2-pci.o i2c-amd-mp2-plat.o +obj-$(CONFIG_I2C_ASPEED) += i2c-aspeed.o +obj-$(CONFIG_I2C_AT91) += i2c-at91.o +i2c-at91-objs := i2c-at91-core.o i2c-at91-master.o +ifeq ($(CONFIG_I2C_AT91_SLAVE_EXPERIMENTAL),y) + i2c-at91-objs += i2c-at91-slave.o +endif +obj-$(CONFIG_I2C_AU1550) += i2c-au1550.o +obj-$(CONFIG_I2C_AXXIA) += i2c-axxia.o +obj-$(CONFIG_I2C_BCM2835) += i2c-bcm2835.o +obj-$(CONFIG_I2C_BCM_IPROC) += i2c-bcm-iproc.o +obj-$(CONFIG_I2C_CADENCE) += i2c-cadence.o +obj-$(CONFIG_I2C_CBUS_GPIO) += i2c-cbus-gpio.o +obj-$(CONFIG_I2C_CPM) += i2c-cpm.o +obj-$(CONFIG_I2C_DAVINCI) += i2c-davinci.o +obj-$(CONFIG_I2C_DESIGNWARE_CORE) += i2c-designware-core.o +i2c-designware-core-y := i2c-designware-common.o +i2c-designware-core-y += i2c-designware-master.o +i2c-designware-core-$(CONFIG_I2C_DESIGNWARE_SLAVE) += i2c-designware-slave.o +obj-$(CONFIG_I2C_DESIGNWARE_PLATFORM) += i2c-designware-platform.o +i2c-designware-platform-y := i2c-designware-platdrv.o +i2c-designware-platform-$(CONFIG_I2C_DESIGNWARE_AMDPSP) += i2c-designware-amdpsp.o +i2c-designware-platform-$(CONFIG_I2C_DESIGNWARE_BAYTRAIL) += i2c-designware-baytrail.o +obj-$(CONFIG_I2C_DESIGNWARE_PCI) += i2c-designware-pci.o +i2c-designware-pci-y := i2c-designware-pcidrv.o +obj-$(CONFIG_I2C_DIGICOLOR) += i2c-digicolor.o +obj-$(CONFIG_I2C_EG20T) += i2c-eg20t.o +obj-$(CONFIG_I2C_EMEV2) += i2c-emev2.o +obj-$(CONFIG_I2C_EXYNOS5) += i2c-exynos5.o +obj-$(CONFIG_I2C_GPIO) += i2c-gpio.o +obj-$(CONFIG_I2C_HIGHLANDER) += i2c-highlander.o +obj-$(CONFIG_I2C_HISI) += i2c-hisi.o +obj-$(CONFIG_I2C_HIX5HD2) += i2c-hix5hd2.o +obj-$(CONFIG_I2C_IBM_IIC) += i2c-ibm_iic.o +obj-$(CONFIG_I2C_IMG) += i2c-img-scb.o +obj-$(CONFIG_I2C_IMX) += i2c-imx.o +obj-$(CONFIG_I2C_IMX_LPI2C) += i2c-imx-lpi2c.o +obj-$(CONFIG_I2C_IOP3XX) += i2c-iop3xx.o +obj-$(CONFIG_I2C_JZ4780) += i2c-jz4780.o +obj-$(CONFIG_I2C_KEMPLD) += i2c-kempld.o +obj-$(CONFIG_I2C_LPC2K) += i2c-lpc2k.o +obj-$(CONFIG_I2C_LS2X) += i2c-ls2x.o +obj-$(CONFIG_I2C_MESON) += i2c-meson.o +obj-$(CONFIG_I2C_MICROCHIP_CORE) += i2c-microchip-corei2c.o +obj-$(CONFIG_I2C_MPC) += i2c-mpc.o +obj-$(CONFIG_I2C_MT65XX) += i2c-mt65xx.o +obj-$(CONFIG_I2C_MT7621) += i2c-mt7621.o +obj-$(CONFIG_I2C_MV64XXX) += i2c-mv64xxx.o +obj-$(CONFIG_I2C_MXS) += i2c-mxs.o +obj-$(CONFIG_I2C_NOMADIK) += i2c-nomadik.o +obj-$(CONFIG_I2C_NPCM) += i2c-npcm7xx.o +obj-$(CONFIG_I2C_OCORES) += i2c-ocores.o +obj-$(CONFIG_I2C_OMAP) += i2c-omap.o +obj-$(CONFIG_I2C_OWL) += i2c-owl.o +i2c-pasemi-objs := i2c-pasemi-core.o i2c-pasemi-pci.o +obj-$(CONFIG_I2C_PASEMI) += i2c-pasemi.o +i2c-apple-objs := i2c-pasemi-core.o i2c-pasemi-platform.o +obj-$(CONFIG_I2C_APPLE) += i2c-apple.o +obj-$(CONFIG_I2C_PCA_PLATFORM) += i2c-pca-platform.o +obj-$(CONFIG_I2C_PNX) += i2c-pnx.o +obj-$(CONFIG_I2C_PXA) += i2c-pxa.o +obj-$(CONFIG_I2C_PXA_PCI) += i2c-pxa-pci.o +obj-$(CONFIG_I2C_QCOM_CCI) += i2c-qcom-cci.o +obj-$(CONFIG_I2C_QCOM_GENI) += i2c-qcom-geni.o +obj-$(CONFIG_I2C_QUP) += i2c-qup.o +obj-$(CONFIG_I2C_RIIC) += i2c-riic.o +obj-$(CONFIG_I2C_RK3X) += i2c-rk3x.o +obj-$(CONFIG_I2C_RZV2M) += i2c-rzv2m.o +obj-$(CONFIG_I2C_S3C2410) += i2c-s3c2410.o +obj-$(CONFIG_I2C_SH7760) += i2c-sh7760.o +obj-$(CONFIG_I2C_SH_MOBILE) += i2c-sh_mobile.o +obj-$(CONFIG_I2C_SIMTEC) += i2c-simtec.o +obj-$(CONFIG_I2C_SPRD) += i2c-sprd.o +obj-$(CONFIG_I2C_ST) += i2c-st.o +obj-$(CONFIG_I2C_STM32F4) += i2c-stm32f4.o +i2c-stm32f7-drv-objs := i2c-stm32f7.o i2c-stm32.o +obj-$(CONFIG_I2C_STM32F7) += i2c-stm32f7-drv.o +obj-$(CONFIG_I2C_SUN6I_P2WI) += i2c-sun6i-p2wi.o +obj-$(CONFIG_I2C_SYNQUACER) += i2c-synquacer.o +obj-$(CONFIG_I2C_TEGRA) += i2c-tegra.o +obj-$(CONFIG_I2C_TEGRA_BPMP) += i2c-tegra-bpmp.o +obj-$(CONFIG_I2C_UNIPHIER) += i2c-uniphier.o +obj-$(CONFIG_I2C_UNIPHIER_F) += i2c-uniphier-f.o +obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o +obj-$(CONFIG_I2C_WMT) += i2c-wmt.o +i2c-octeon-objs := i2c-octeon-core.o i2c-octeon-platdrv.o +obj-$(CONFIG_I2C_OCTEON) += i2c-octeon.o +i2c-thunderx-objs := i2c-octeon-core.o i2c-thunderx-pcidrv.o +obj-$(CONFIG_I2C_THUNDERX) += i2c-thunderx.o +obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o +obj-$(CONFIG_I2C_XLP9XX) += i2c-xlp9xx.o +obj-$(CONFIG_I2C_RCAR) += i2c-rcar.o +obj-$(CONFIG_I2C_GXP) += i2c-gxp.o + +# External I2C/SMBus adapter drivers +obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o +obj-$(CONFIG_I2C_DLN2) += i2c-dln2.o +obj-$(CONFIG_I2C_CP2615) += i2c-cp2615.o +obj-$(CONFIG_I2C_PARPORT) += i2c-parport.o +obj-$(CONFIG_I2C_PCI1XXXX) += i2c-mchp-pci1xxxx.o +obj-$(CONFIG_I2C_ROBOTFUZZ_OSIF) += i2c-robotfuzz-osif.o +obj-$(CONFIG_I2C_TAOS_EVM) += i2c-taos-evm.o +obj-$(CONFIG_I2C_TINY_USB) += i2c-tiny-usb.o +obj-$(CONFIG_I2C_VIPERBOARD) += i2c-viperboard.o + +# Other I2C/SMBus bus drivers +obj-$(CONFIG_I2C_ACORN) += i2c-acorn.o +obj-$(CONFIG_I2C_BCM_KONA) += i2c-bcm-kona.o +obj-$(CONFIG_I2C_BRCMSTB) += i2c-brcmstb.o +obj-$(CONFIG_I2C_CROS_EC_TUNNEL) += i2c-cros-ec-tunnel.o +obj-$(CONFIG_I2C_ELEKTOR) += i2c-elektor.o +obj-$(CONFIG_I2C_ICY) += i2c-icy.o +obj-$(CONFIG_I2C_MLXBF) += i2c-mlxbf.o +obj-$(CONFIG_I2C_MLXCPLD) += i2c-mlxcpld.o +obj-$(CONFIG_I2C_OPAL) += i2c-opal.o +obj-$(CONFIG_I2C_PCA_ISA) += i2c-pca-isa.o +obj-$(CONFIG_I2C_SIBYTE) += i2c-sibyte.o +obj-$(CONFIG_I2C_XGENE_SLIMPRO) += i2c-xgene-slimpro.o +obj-$(CONFIG_SCx200_ACB) += scx200_acb.o +obj-$(CONFIG_I2C_FSI) += i2c-fsi.o +obj-$(CONFIG_I2C_VIRTIO) += i2c-virtio.o + +ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG diff --git a/drivers/i2c/busses/i2c-acorn.c b/drivers/i2c/busses/i2c-acorn.c new file mode 100644 index 000000000..34bbbb8c5 --- /dev/null +++ b/drivers/i2c/busses/i2c-acorn.c @@ -0,0 +1,96 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ARM IOC/IOMD i2c driver. + * + * Copyright (C) 2000 Russell King + * + * On Acorn machines, the following i2c devices are on the bus: + * - PCF8583 real time clock & static RAM + */ +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/i2c-algo-bit.h> +#include <linux/io.h> + +#include <mach/hardware.h> +#include <asm/hardware/ioc.h> + +#define FORCE_ONES 0xdc +#define SCL 0x02 +#define SDA 0x01 + +/* + * We must preserve all non-i2c output bits in IOC_CONTROL. + * Note also that we need to preserve the value of SCL and + * SDA outputs as well (which may be different from the + * values read back from IOC_CONTROL). + */ +static u_int force_ones; + +static void ioc_setscl(void *data, int state) +{ + u_int ioc_control = ioc_readb(IOC_CONTROL) & ~(SCL | SDA); + u_int ones = force_ones; + + if (state) + ones |= SCL; + else + ones &= ~SCL; + + force_ones = ones; + + ioc_writeb(ioc_control | ones, IOC_CONTROL); +} + +static void ioc_setsda(void *data, int state) +{ + u_int ioc_control = ioc_readb(IOC_CONTROL) & ~(SCL | SDA); + u_int ones = force_ones; + + if (state) + ones |= SDA; + else + ones &= ~SDA; + + force_ones = ones; + + ioc_writeb(ioc_control | ones, IOC_CONTROL); +} + +static int ioc_getscl(void *data) +{ + return (ioc_readb(IOC_CONTROL) & SCL) != 0; +} + +static int ioc_getsda(void *data) +{ + return (ioc_readb(IOC_CONTROL) & SDA) != 0; +} + +static struct i2c_algo_bit_data ioc_data = { + .setsda = ioc_setsda, + .setscl = ioc_setscl, + .getsda = ioc_getsda, + .getscl = ioc_getscl, + .udelay = 80, + .timeout = HZ, +}; + +static struct i2c_adapter ioc_ops = { + .nr = 0, + .name = "ioc", + .algo_data = &ioc_data, +}; + +static int __init i2c_ioc_init(void) +{ + force_ones = FORCE_ONES | SCL | SDA; + + return i2c_bit_add_numbered_bus(&ioc_ops); +} + +module_init(i2c_ioc_init); + +MODULE_AUTHOR("Russell King <linux@armlinux.org.uk>"); +MODULE_DESCRIPTION("ARM IOC/IOMD i2c driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-ali1535.c b/drivers/i2c/busses/i2c-ali1535.c new file mode 100644 index 000000000..ee83c4581 --- /dev/null +++ b/drivers/i2c/busses/i2c-ali1535.c @@ -0,0 +1,532 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2000 Frodo Looijaard <frodol@dds.nl>, + * Philip Edelbrock <phil@netroedge.com>, + * Mark D. Studebaker <mdsxyz123@yahoo.com>, + * Dan Eaton <dan.eaton@rocketlogix.com> and + * Stephen Rousset <stephen.rousset@rocketlogix.com> +*/ + +/* + This is the driver for the SMB Host controller on + Acer Labs Inc. (ALI) M1535 South Bridge. + + The M1535 is a South bridge for portable systems. + It is very similar to the M15x3 South bridges also produced + by Acer Labs Inc. Some of the registers within the part + have moved and some have been redefined slightly. Additionally, + the sequencing of the SMBus transactions has been modified + to be more consistent with the sequencing recommended by + the manufacturer and observed through testing. These + changes are reflected in this driver and can be identified + by comparing this driver to the i2c-ali15x3 driver. + For an overview of these chips see http://www.acerlabs.com + + The SMB controller is part of the 7101 device, which is an + ACPI-compliant Power Management Unit (PMU). + + The whole 7101 device has to be enabled for the SMB to work. + You can't just enable the SMB alone. + The SMB and the ACPI have separate I/O spaces. + We make sure that the SMB is enabled. We leave the ACPI alone. + + This driver controls the SMB Host only. + + This driver does not use interrupts. +*/ + + +/* Note: we assume there can only be one ALI1535, with one SMBus interface */ + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/stddef.h> +#include <linux/delay.h> +#include <linux/ioport.h> +#include <linux/i2c.h> +#include <linux/acpi.h> +#include <linux/io.h> + + +/* ALI1535 SMBus address offsets */ +#define SMBHSTSTS (0 + ali1535_smba) +#define SMBHSTTYP (1 + ali1535_smba) +#define SMBHSTPORT (2 + ali1535_smba) +#define SMBHSTCMD (7 + ali1535_smba) +#define SMBHSTADD (3 + ali1535_smba) +#define SMBHSTDAT0 (4 + ali1535_smba) +#define SMBHSTDAT1 (5 + ali1535_smba) +#define SMBBLKDAT (6 + ali1535_smba) + +/* PCI Address Constants */ +#define SMBCOM 0x004 +#define SMBREV 0x008 +#define SMBCFG 0x0D1 +#define SMBBA 0x0E2 +#define SMBHSTCFG 0x0F0 +#define SMBCLK 0x0F2 + +/* Other settings */ +#define MAX_TIMEOUT 500 /* times 1/100 sec */ +#define ALI1535_SMB_IOSIZE 32 + +#define ALI1535_SMB_DEFAULTBASE 0x8040 + +/* ALI1535 address lock bits */ +#define ALI1535_LOCK 0x06 /* dwe */ + +/* ALI1535 command constants */ +#define ALI1535_QUICK 0x00 +#define ALI1535_BYTE 0x10 +#define ALI1535_BYTE_DATA 0x20 +#define ALI1535_WORD_DATA 0x30 +#define ALI1535_BLOCK_DATA 0x40 +#define ALI1535_I2C_READ 0x60 + +#define ALI1535_DEV10B_EN 0x80 /* Enable 10-bit addressing in */ + /* I2C read */ +#define ALI1535_T_OUT 0x08 /* Time-out Command (write) */ +#define ALI1535_A_HIGH_BIT9 0x08 /* Bit 9 of 10-bit address in */ + /* Alert-Response-Address */ + /* (read) */ +#define ALI1535_KILL 0x04 /* Kill Command (write) */ +#define ALI1535_A_HIGH_BIT8 0x04 /* Bit 8 of 10-bit address in */ + /* Alert-Response-Address */ + /* (read) */ + +#define ALI1535_D_HI_MASK 0x03 /* Mask for isolating bits 9-8 */ + /* of 10-bit address in I2C */ + /* Read Command */ + +/* ALI1535 status register bits */ +#define ALI1535_STS_IDLE 0x04 +#define ALI1535_STS_BUSY 0x08 /* host busy */ +#define ALI1535_STS_DONE 0x10 /* transaction complete */ +#define ALI1535_STS_DEV 0x20 /* device error */ +#define ALI1535_STS_BUSERR 0x40 /* bus error */ +#define ALI1535_STS_FAIL 0x80 /* failed bus transaction */ +#define ALI1535_STS_ERR 0xE0 /* all the bad error bits */ + +#define ALI1535_BLOCK_CLR 0x04 /* reset block data index */ + +/* ALI1535 device address register bits */ +#define ALI1535_RD_ADDR 0x01 /* Read/Write Bit in Device */ + /* Address field */ + /* -> Write = 0 */ + /* -> Read = 1 */ +#define ALI1535_SMBIO_EN 0x04 /* SMB I/O Space enable */ + +static struct pci_driver ali1535_driver; +static unsigned long ali1535_smba; +static unsigned short ali1535_offset; + +/* Detect whether a ALI1535 can be found, and initialize it, where necessary. + Note the differences between kernels with the old PCI BIOS interface and + newer kernels with the real PCI interface. In compat.h some things are + defined to make the transition easier. */ +static int ali1535_setup(struct pci_dev *dev) +{ + int retval; + unsigned char temp; + + /* Check the following things: + - SMB I/O address is initialized + - Device is enabled + - We can use the addresses + */ + + retval = pci_enable_device(dev); + if (retval) { + dev_err(&dev->dev, "ALI1535_smb can't enable device\n"); + goto exit; + } + + /* Determine the address of the SMBus area */ + pci_read_config_word(dev, SMBBA, &ali1535_offset); + dev_dbg(&dev->dev, "ALI1535_smb is at offset 0x%04x\n", ali1535_offset); + ali1535_offset &= (0xffff & ~(ALI1535_SMB_IOSIZE - 1)); + if (ali1535_offset == 0) { + dev_warn(&dev->dev, + "ALI1535_smb region uninitialized - upgrade BIOS?\n"); + retval = -ENODEV; + goto exit; + } + + if (pci_resource_flags(dev, 0) & IORESOURCE_IO) + ali1535_smba = pci_resource_start(dev, 0) + ali1535_offset; + else + ali1535_smba = ali1535_offset; + + retval = acpi_check_region(ali1535_smba, ALI1535_SMB_IOSIZE, + ali1535_driver.name); + if (retval) + goto exit; + + if (!request_region(ali1535_smba, ALI1535_SMB_IOSIZE, + ali1535_driver.name)) { + dev_err(&dev->dev, "ALI1535_smb region 0x%lx already in use!\n", + ali1535_smba); + retval = -EBUSY; + goto exit; + } + + /* check if whole device is enabled */ + pci_read_config_byte(dev, SMBCFG, &temp); + if ((temp & ALI1535_SMBIO_EN) == 0) { + dev_err(&dev->dev, "SMB device not enabled - upgrade BIOS?\n"); + retval = -ENODEV; + goto exit_free; + } + + /* Is SMB Host controller enabled? */ + pci_read_config_byte(dev, SMBHSTCFG, &temp); + if ((temp & 1) == 0) { + dev_err(&dev->dev, "SMBus controller not enabled - upgrade BIOS?\n"); + retval = -ENODEV; + goto exit_free; + } + + /* set SMB clock to 74KHz as recommended in data sheet */ + pci_write_config_byte(dev, SMBCLK, 0x20); + + /* + The interrupt routing for SMB is set up in register 0x77 in the + 1533 ISA Bridge device, NOT in the 7101 device. + Don't bother with finding the 1533 device and reading the register. + if ((....... & 0x0F) == 1) + dev_dbg(&dev->dev, "ALI1535 using Interrupt 9 for SMBus.\n"); + */ + pci_read_config_byte(dev, SMBREV, &temp); + dev_dbg(&dev->dev, "SMBREV = 0x%X\n", temp); + dev_dbg(&dev->dev, "ALI1535_smba = 0x%lx\n", ali1535_smba); + + return 0; + +exit_free: + release_region(ali1535_smba, ALI1535_SMB_IOSIZE); +exit: + return retval; +} + +static int ali1535_transaction(struct i2c_adapter *adap) +{ + int temp; + int result = 0; + int timeout = 0; + + dev_dbg(&adap->dev, "Transaction (pre): STS=%02x, TYP=%02x, " + "CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n", + inb_p(SMBHSTSTS), inb_p(SMBHSTTYP), inb_p(SMBHSTCMD), + inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1)); + + /* get status */ + temp = inb_p(SMBHSTSTS); + + /* Make sure the SMBus host is ready to start transmitting */ + /* Check the busy bit first */ + if (temp & ALI1535_STS_BUSY) { + /* If the host controller is still busy, it may have timed out + * in the previous transaction, resulting in a "SMBus Timeout" + * printk. I've tried the following to reset a stuck busy bit. + * 1. Reset the controller with an KILL command. (this + * doesn't seem to clear the controller if an external + * device is hung) + * 2. Reset the controller and the other SMBus devices with a + * T_OUT command. (this clears the host busy bit if an + * external device is hung, but it comes back upon a new + * access to a device) + * 3. Disable and reenable the controller in SMBHSTCFG. Worst + * case, nothing seems to work except power reset. + */ + + /* Try resetting entire SMB bus, including other devices - This + * may not work either - it clears the BUSY bit but then the + * BUSY bit may come back on when you try and use the chip + * again. If that's the case you are stuck. + */ + dev_info(&adap->dev, + "Resetting entire SMB Bus to clear busy condition (%02x)\n", + temp); + outb_p(ALI1535_T_OUT, SMBHSTTYP); + temp = inb_p(SMBHSTSTS); + } + + /* now check the error bits and the busy bit */ + if (temp & (ALI1535_STS_ERR | ALI1535_STS_BUSY)) { + /* do a clear-on-write */ + outb_p(0xFF, SMBHSTSTS); + temp = inb_p(SMBHSTSTS); + if (temp & (ALI1535_STS_ERR | ALI1535_STS_BUSY)) { + /* This is probably going to be correctable only by a + * power reset as one of the bits now appears to be + * stuck */ + /* This may be a bus or device with electrical problems. */ + dev_err(&adap->dev, + "SMBus reset failed! (0x%02x) - controller or " + "device on bus is probably hung\n", temp); + return -EBUSY; + } + } else { + /* check and clear done bit */ + if (temp & ALI1535_STS_DONE) + outb_p(temp, SMBHSTSTS); + } + + /* start the transaction by writing anything to the start register */ + outb_p(0xFF, SMBHSTPORT); + + /* We will always wait for a fraction of a second! */ + timeout = 0; + do { + usleep_range(1000, 2000); + temp = inb_p(SMBHSTSTS); + } while (((temp & ALI1535_STS_BUSY) && !(temp & ALI1535_STS_IDLE)) + && (timeout++ < MAX_TIMEOUT)); + + /* If the SMBus is still busy, we give up */ + if (timeout > MAX_TIMEOUT) { + result = -ETIMEDOUT; + dev_err(&adap->dev, "SMBus Timeout!\n"); + } + + if (temp & ALI1535_STS_FAIL) { + result = -EIO; + dev_dbg(&adap->dev, "Error: Failed bus transaction\n"); + } + + /* Unfortunately the ALI SMB controller maps "no response" and "bus + * collision" into a single bit. No response is the usual case so don't + * do a printk. This means that bus collisions go unreported. + */ + if (temp & ALI1535_STS_BUSERR) { + result = -ENXIO; + dev_dbg(&adap->dev, + "Error: no response or bus collision ADD=%02x\n", + inb_p(SMBHSTADD)); + } + + /* haven't ever seen this */ + if (temp & ALI1535_STS_DEV) { + result = -EIO; + dev_err(&adap->dev, "Error: device error\n"); + } + + /* check to see if the "command complete" indication is set */ + if (!(temp & ALI1535_STS_DONE)) { + result = -ETIMEDOUT; + dev_err(&adap->dev, "Error: command never completed\n"); + } + + dev_dbg(&adap->dev, "Transaction (post): STS=%02x, TYP=%02x, " + "CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n", + inb_p(SMBHSTSTS), inb_p(SMBHSTTYP), inb_p(SMBHSTCMD), + inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1)); + + /* take consequent actions for error conditions */ + if (!(temp & ALI1535_STS_DONE)) { + /* issue "kill" to reset host controller */ + outb_p(ALI1535_KILL, SMBHSTTYP); + outb_p(0xFF, SMBHSTSTS); + } else if (temp & ALI1535_STS_ERR) { + /* issue "timeout" to reset all devices on bus */ + outb_p(ALI1535_T_OUT, SMBHSTTYP); + outb_p(0xFF, SMBHSTSTS); + } + + return result; +} + +/* Return negative errno on error. */ +static s32 ali1535_access(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, u8 command, + int size, union i2c_smbus_data *data) +{ + int i, len; + int temp; + int timeout; + s32 result = 0; + + /* make sure SMBus is idle */ + temp = inb_p(SMBHSTSTS); + for (timeout = 0; + (timeout < MAX_TIMEOUT) && !(temp & ALI1535_STS_IDLE); + timeout++) { + usleep_range(1000, 2000); + temp = inb_p(SMBHSTSTS); + } + if (timeout >= MAX_TIMEOUT) + dev_warn(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp); + + /* clear status register (clear-on-write) */ + outb_p(0xFF, SMBHSTSTS); + + switch (size) { + case I2C_SMBUS_QUICK: + outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMBHSTADD); + size = ALI1535_QUICK; + outb_p(size, SMBHSTTYP); /* output command */ + break; + case I2C_SMBUS_BYTE: + outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMBHSTADD); + size = ALI1535_BYTE; + outb_p(size, SMBHSTTYP); /* output command */ + if (read_write == I2C_SMBUS_WRITE) + outb_p(command, SMBHSTCMD); + break; + case I2C_SMBUS_BYTE_DATA: + outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMBHSTADD); + size = ALI1535_BYTE_DATA; + outb_p(size, SMBHSTTYP); /* output command */ + outb_p(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) + outb_p(data->byte, SMBHSTDAT0); + break; + case I2C_SMBUS_WORD_DATA: + outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMBHSTADD); + size = ALI1535_WORD_DATA; + outb_p(size, SMBHSTTYP); /* output command */ + outb_p(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) { + outb_p(data->word & 0xff, SMBHSTDAT0); + outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1); + } + break; + case I2C_SMBUS_BLOCK_DATA: + outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMBHSTADD); + size = ALI1535_BLOCK_DATA; + outb_p(size, SMBHSTTYP); /* output command */ + outb_p(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) { + len = data->block[0]; + if (len < 0) { + len = 0; + data->block[0] = len; + } + if (len > 32) { + len = 32; + data->block[0] = len; + } + outb_p(len, SMBHSTDAT0); + /* Reset SMBBLKDAT */ + outb_p(inb_p(SMBHSTTYP) | ALI1535_BLOCK_CLR, SMBHSTTYP); + for (i = 1; i <= len; i++) + outb_p(data->block[i], SMBBLKDAT); + } + break; + default: + dev_warn(&adap->dev, "Unsupported transaction %d\n", size); + result = -EOPNOTSUPP; + goto EXIT; + } + + result = ali1535_transaction(adap); + if (result) + goto EXIT; + + if ((read_write == I2C_SMBUS_WRITE) || (size == ALI1535_QUICK)) { + result = 0; + goto EXIT; + } + + switch (size) { + case ALI1535_BYTE: /* Result put in SMBHSTDAT0 */ + data->byte = inb_p(SMBHSTDAT0); + break; + case ALI1535_BYTE_DATA: + data->byte = inb_p(SMBHSTDAT0); + break; + case ALI1535_WORD_DATA: + data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8); + break; + case ALI1535_BLOCK_DATA: + len = inb_p(SMBHSTDAT0); + if (len > 32) + len = 32; + data->block[0] = len; + /* Reset SMBBLKDAT */ + outb_p(inb_p(SMBHSTTYP) | ALI1535_BLOCK_CLR, SMBHSTTYP); + for (i = 1; i <= data->block[0]; i++) { + data->block[i] = inb_p(SMBBLKDAT); + dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n", + len, i, data->block[i]); + } + break; + } +EXIT: + return result; +} + + +static u32 ali1535_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_BLOCK_DATA; +} + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = ali1535_access, + .functionality = ali1535_func, +}; + +static struct i2c_adapter ali1535_adapter = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = &smbus_algorithm, +}; + +static const struct pci_device_id ali1535_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) }, + { }, +}; + +MODULE_DEVICE_TABLE(pci, ali1535_ids); + +static int ali1535_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + if (ali1535_setup(dev)) { + dev_warn(&dev->dev, + "ALI1535 not detected, module not inserted.\n"); + return -ENODEV; + } + + /* set up the sysfs linkage to our parent device */ + ali1535_adapter.dev.parent = &dev->dev; + + snprintf(ali1535_adapter.name, sizeof(ali1535_adapter.name), + "SMBus ALI1535 adapter at %04x", ali1535_offset); + return i2c_add_adapter(&ali1535_adapter); +} + +static void ali1535_remove(struct pci_dev *dev) +{ + i2c_del_adapter(&ali1535_adapter); + release_region(ali1535_smba, ALI1535_SMB_IOSIZE); + + /* + * do not call pci_disable_device(dev) since it can cause hard hangs on + * some systems during power-off + */ +} + +static struct pci_driver ali1535_driver = { + .name = "ali1535_smbus", + .id_table = ali1535_ids, + .probe = ali1535_probe, + .remove = ali1535_remove, +}; + +module_pci_driver(ali1535_driver); + +MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>"); +MODULE_AUTHOR("Philip Edelbrock <phil@netroedge.com>"); +MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>"); +MODULE_AUTHOR("Dan Eaton <dan.eaton@rocketlogix.com>"); +MODULE_DESCRIPTION("ALI1535 SMBus driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-ali1563.c b/drivers/i2c/busses/i2c-ali1563.c new file mode 100644 index 000000000..55a9e93fb --- /dev/null +++ b/drivers/i2c/busses/i2c-ali1563.c @@ -0,0 +1,442 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * i2c-ali1563.c - i2c driver for the ALi 1563 Southbridge + * + * Copyright (C) 2004 Patrick Mochel + * 2005 Rudolf Marek <r.marek@assembler.cz> + * + * The 1563 southbridge is deceptively similar to the 1533, with a + * few notable exceptions. One of those happens to be the fact they + * upgraded the i2c core to be 2.0 compliant, and happens to be almost + * identical to the i2c controller found in the Intel 801 south + * bridges. + * + * This driver is based on a mix of the 15x3, 1535, and i801 drivers, + * with a little help from the ALi 1563 spec. + */ + +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/pci.h> +#include <linux/acpi.h> + +#define ALI1563_MAX_TIMEOUT 500 +#define ALI1563_SMBBA 0x80 +#define ALI1563_SMB_IOEN 1 +#define ALI1563_SMB_HOSTEN 2 +#define ALI1563_SMB_IOSIZE 16 + +#define SMB_HST_STS (ali1563_smba + 0) +#define SMB_HST_CNTL1 (ali1563_smba + 1) +#define SMB_HST_CNTL2 (ali1563_smba + 2) +#define SMB_HST_CMD (ali1563_smba + 3) +#define SMB_HST_ADD (ali1563_smba + 4) +#define SMB_HST_DAT0 (ali1563_smba + 5) +#define SMB_HST_DAT1 (ali1563_smba + 6) +#define SMB_BLK_DAT (ali1563_smba + 7) + +#define HST_STS_BUSY 0x01 +#define HST_STS_INTR 0x02 +#define HST_STS_DEVERR 0x04 +#define HST_STS_BUSERR 0x08 +#define HST_STS_FAIL 0x10 +#define HST_STS_DONE 0x80 +#define HST_STS_BAD 0x1c + + +#define HST_CNTL1_TIMEOUT 0x80 +#define HST_CNTL1_LAST 0x40 + +#define HST_CNTL2_KILL 0x04 +#define HST_CNTL2_START 0x40 +#define HST_CNTL2_QUICK 0x00 +#define HST_CNTL2_BYTE 0x01 +#define HST_CNTL2_BYTE_DATA 0x02 +#define HST_CNTL2_WORD_DATA 0x03 +#define HST_CNTL2_BLOCK 0x05 + + +#define HST_CNTL2_SIZEMASK 0x38 + +static struct pci_driver ali1563_pci_driver; +static unsigned short ali1563_smba; + +static int ali1563_transaction(struct i2c_adapter *a, int size) +{ + u32 data; + int timeout; + int status = -EIO; + + dev_dbg(&a->dev, "Transaction (pre): STS=%02x, CNTL1=%02x, " + "CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n", + inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2), + inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0), + inb_p(SMB_HST_DAT1)); + + data = inb_p(SMB_HST_STS); + if (data & HST_STS_BAD) { + dev_err(&a->dev, "ali1563: Trying to reset busy device\n"); + outb_p(data | HST_STS_BAD, SMB_HST_STS); + data = inb_p(SMB_HST_STS); + if (data & HST_STS_BAD) + return -EBUSY; + } + outb_p(inb_p(SMB_HST_CNTL2) | HST_CNTL2_START, SMB_HST_CNTL2); + + timeout = ALI1563_MAX_TIMEOUT; + do { + msleep(1); + } while (((data = inb_p(SMB_HST_STS)) & HST_STS_BUSY) && --timeout); + + dev_dbg(&a->dev, "Transaction (post): STS=%02x, CNTL1=%02x, " + "CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n", + inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2), + inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0), + inb_p(SMB_HST_DAT1)); + + if (timeout && !(data & HST_STS_BAD)) + return 0; + + if (!timeout) { + dev_err(&a->dev, "Timeout - Trying to KILL transaction!\n"); + /* Issue 'kill' to host controller */ + outb_p(HST_CNTL2_KILL, SMB_HST_CNTL2); + data = inb_p(SMB_HST_STS); + status = -ETIMEDOUT; + } + + /* device error - no response, ignore the autodetection case */ + if (data & HST_STS_DEVERR) { + if (size != HST_CNTL2_QUICK) + dev_err(&a->dev, "Device error!\n"); + status = -ENXIO; + } + /* bus collision */ + if (data & HST_STS_BUSERR) { + dev_err(&a->dev, "Bus collision!\n"); + /* Issue timeout, hoping it helps */ + outb_p(HST_CNTL1_TIMEOUT, SMB_HST_CNTL1); + } + + if (data & HST_STS_FAIL) { + dev_err(&a->dev, "Cleaning fail after KILL!\n"); + outb_p(0x0, SMB_HST_CNTL2); + } + + return status; +} + +static int ali1563_block_start(struct i2c_adapter *a) +{ + u32 data; + int timeout; + int status = -EIO; + + dev_dbg(&a->dev, "Block (pre): STS=%02x, CNTL1=%02x, " + "CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n", + inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2), + inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0), + inb_p(SMB_HST_DAT1)); + + data = inb_p(SMB_HST_STS); + if (data & HST_STS_BAD) { + dev_warn(&a->dev, "ali1563: Trying to reset busy device\n"); + outb_p(data | HST_STS_BAD, SMB_HST_STS); + data = inb_p(SMB_HST_STS); + if (data & HST_STS_BAD) + return -EBUSY; + } + + /* Clear byte-ready bit */ + outb_p(data | HST_STS_DONE, SMB_HST_STS); + + /* Start transaction and wait for byte-ready bit to be set */ + outb_p(inb_p(SMB_HST_CNTL2) | HST_CNTL2_START, SMB_HST_CNTL2); + + timeout = ALI1563_MAX_TIMEOUT; + do { + msleep(1); + } while (!((data = inb_p(SMB_HST_STS)) & HST_STS_DONE) && --timeout); + + dev_dbg(&a->dev, "Block (post): STS=%02x, CNTL1=%02x, " + "CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n", + inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2), + inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0), + inb_p(SMB_HST_DAT1)); + + if (timeout && !(data & HST_STS_BAD)) + return 0; + + if (timeout == 0) + status = -ETIMEDOUT; + + if (data & HST_STS_DEVERR) + status = -ENXIO; + + dev_err(&a->dev, "SMBus Error: %s%s%s%s%s\n", + timeout ? "" : "Timeout ", + data & HST_STS_FAIL ? "Transaction Failed " : "", + data & HST_STS_BUSERR ? "No response or Bus Collision " : "", + data & HST_STS_DEVERR ? "Device Error " : "", + !(data & HST_STS_DONE) ? "Transaction Never Finished " : ""); + return status; +} + +static int ali1563_block(struct i2c_adapter *a, + union i2c_smbus_data *data, u8 rw) +{ + int i, len; + int error = 0; + + /* Do we need this? */ + outb_p(HST_CNTL1_LAST, SMB_HST_CNTL1); + + if (rw == I2C_SMBUS_WRITE) { + len = data->block[0]; + if (len < 1) + len = 1; + else if (len > 32) + len = 32; + outb_p(len, SMB_HST_DAT0); + outb_p(data->block[1], SMB_BLK_DAT); + } else + len = 32; + + outb_p(inb_p(SMB_HST_CNTL2) | HST_CNTL2_BLOCK, SMB_HST_CNTL2); + + for (i = 0; i < len; i++) { + if (rw == I2C_SMBUS_WRITE) { + outb_p(data->block[i + 1], SMB_BLK_DAT); + error = ali1563_block_start(a); + if (error) + break; + } else { + error = ali1563_block_start(a); + if (error) + break; + if (i == 0) { + len = inb_p(SMB_HST_DAT0); + if (len < 1) + len = 1; + else if (len > 32) + len = 32; + } + data->block[i+1] = inb_p(SMB_BLK_DAT); + } + } + /* Do we need this? */ + outb_p(HST_CNTL1_LAST, SMB_HST_CNTL1); + return error; +} + +static s32 ali1563_access(struct i2c_adapter *a, u16 addr, + unsigned short flags, char rw, u8 cmd, + int size, union i2c_smbus_data *data) +{ + int error = 0; + int timeout; + u32 reg; + + for (timeout = ALI1563_MAX_TIMEOUT; timeout; timeout--) { + reg = inb_p(SMB_HST_STS); + if (!(reg & HST_STS_BUSY)) + break; + } + if (!timeout) + dev_warn(&a->dev, "SMBus not idle. HST_STS = %02x\n", reg); + outb_p(0xff, SMB_HST_STS); + + /* Map the size to what the chip understands */ + switch (size) { + case I2C_SMBUS_QUICK: + size = HST_CNTL2_QUICK; + break; + case I2C_SMBUS_BYTE: + size = HST_CNTL2_BYTE; + break; + case I2C_SMBUS_BYTE_DATA: + size = HST_CNTL2_BYTE_DATA; + break; + case I2C_SMBUS_WORD_DATA: + size = HST_CNTL2_WORD_DATA; + break; + case I2C_SMBUS_BLOCK_DATA: + size = HST_CNTL2_BLOCK; + break; + default: + dev_warn(&a->dev, "Unsupported transaction %d\n", size); + error = -EOPNOTSUPP; + goto Done; + } + + outb_p(((addr & 0x7f) << 1) | (rw & 0x01), SMB_HST_ADD); + outb_p((inb_p(SMB_HST_CNTL2) & ~HST_CNTL2_SIZEMASK) | + (size << 3), SMB_HST_CNTL2); + + /* Write the command register */ + + switch (size) { + case HST_CNTL2_BYTE: + if (rw == I2C_SMBUS_WRITE) + /* Beware it uses DAT0 register and not CMD! */ + outb_p(cmd, SMB_HST_DAT0); + break; + case HST_CNTL2_BYTE_DATA: + outb_p(cmd, SMB_HST_CMD); + if (rw == I2C_SMBUS_WRITE) + outb_p(data->byte, SMB_HST_DAT0); + break; + case HST_CNTL2_WORD_DATA: + outb_p(cmd, SMB_HST_CMD); + if (rw == I2C_SMBUS_WRITE) { + outb_p(data->word & 0xff, SMB_HST_DAT0); + outb_p((data->word & 0xff00) >> 8, SMB_HST_DAT1); + } + break; + case HST_CNTL2_BLOCK: + outb_p(cmd, SMB_HST_CMD); + error = ali1563_block(a, data, rw); + goto Done; + } + + error = ali1563_transaction(a, size); + if (error) + goto Done; + + if ((rw == I2C_SMBUS_WRITE) || (size == HST_CNTL2_QUICK)) + goto Done; + + switch (size) { + case HST_CNTL2_BYTE: /* Result put in SMBHSTDAT0 */ + data->byte = inb_p(SMB_HST_DAT0); + break; + case HST_CNTL2_BYTE_DATA: + data->byte = inb_p(SMB_HST_DAT0); + break; + case HST_CNTL2_WORD_DATA: + data->word = inb_p(SMB_HST_DAT0) + (inb_p(SMB_HST_DAT1) << 8); + break; + } +Done: + return error; +} + +static u32 ali1563_func(struct i2c_adapter *a) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_BLOCK_DATA; +} + + +static int ali1563_setup(struct pci_dev *dev) +{ + u16 ctrl; + + pci_read_config_word(dev, ALI1563_SMBBA, &ctrl); + + /* SMB I/O Base in high 12 bits and must be aligned with the + * size of the I/O space. */ + ali1563_smba = ctrl & ~(ALI1563_SMB_IOSIZE - 1); + if (!ali1563_smba) { + dev_warn(&dev->dev, "ali1563_smba Uninitialized\n"); + goto Err; + } + + /* Check if device is enabled */ + if (!(ctrl & ALI1563_SMB_HOSTEN)) { + dev_warn(&dev->dev, "Host Controller not enabled\n"); + goto Err; + } + if (!(ctrl & ALI1563_SMB_IOEN)) { + dev_warn(&dev->dev, "I/O space not enabled, trying manually\n"); + pci_write_config_word(dev, ALI1563_SMBBA, + ctrl | ALI1563_SMB_IOEN); + pci_read_config_word(dev, ALI1563_SMBBA, &ctrl); + if (!(ctrl & ALI1563_SMB_IOEN)) { + dev_err(&dev->dev, + "I/O space still not enabled, giving up\n"); + goto Err; + } + } + + if (acpi_check_region(ali1563_smba, ALI1563_SMB_IOSIZE, + ali1563_pci_driver.name)) + goto Err; + + if (!request_region(ali1563_smba, ALI1563_SMB_IOSIZE, + ali1563_pci_driver.name)) { + dev_err(&dev->dev, "Could not allocate I/O space at 0x%04x\n", + ali1563_smba); + goto Err; + } + dev_info(&dev->dev, "Found ALi1563 SMBus at 0x%04x\n", ali1563_smba); + + return 0; +Err: + return -ENODEV; +} + +static void ali1563_shutdown(struct pci_dev *dev) +{ + release_region(ali1563_smba, ALI1563_SMB_IOSIZE); +} + +static const struct i2c_algorithm ali1563_algorithm = { + .smbus_xfer = ali1563_access, + .functionality = ali1563_func, +}; + +static struct i2c_adapter ali1563_adapter = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = &ali1563_algorithm, +}; + +static int ali1563_probe(struct pci_dev *dev, + const struct pci_device_id *id_table) +{ + int error; + + error = ali1563_setup(dev); + if (error) + goto exit; + ali1563_adapter.dev.parent = &dev->dev; + snprintf(ali1563_adapter.name, sizeof(ali1563_adapter.name), + "SMBus ALi 1563 Adapter @ %04x", ali1563_smba); + error = i2c_add_adapter(&ali1563_adapter); + if (error) + goto exit_shutdown; + return 0; + +exit_shutdown: + ali1563_shutdown(dev); +exit: + dev_warn(&dev->dev, "ALi1563 SMBus probe failed (%d)\n", error); + return error; +} + +static void ali1563_remove(struct pci_dev *dev) +{ + i2c_del_adapter(&ali1563_adapter); + ali1563_shutdown(dev); +} + +static const struct pci_device_id ali1563_id_table[] = { + { PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1563) }, + {}, +}; + +MODULE_DEVICE_TABLE(pci, ali1563_id_table); + +static struct pci_driver ali1563_pci_driver = { + .name = "ali1563_smbus", + .id_table = ali1563_id_table, + .probe = ali1563_probe, + .remove = ali1563_remove, +}; + +module_pci_driver(ali1563_pci_driver); + +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-ali15x3.c b/drivers/i2c/busses/i2c-ali15x3.c new file mode 100644 index 000000000..0231c5be6 --- /dev/null +++ b/drivers/i2c/busses/i2c-ali15x3.c @@ -0,0 +1,510 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + Copyright (c) 1999 Frodo Looijaard <frodol@dds.nl> and + Philip Edelbrock <phil@netroedge.com> and + Mark D. Studebaker <mdsxyz123@yahoo.com> + +*/ + +/* + This is the driver for the SMB Host controller on + Acer Labs Inc. (ALI) M1541 and M1543C South Bridges. + + The M1543C is a South bridge for desktop systems. + The M1533 is a South bridge for portable systems. + They are part of the following ALI chipsets: + "Aladdin Pro 2": Includes the M1621 Slot 1 North bridge + with AGP and 100MHz CPU Front Side bus + "Aladdin V": Includes the M1541 Socket 7 North bridge + with AGP and 100MHz CPU Front Side bus + "Aladdin IV": Includes the M1541 Socket 7 North bridge + with host bus up to 83.3 MHz. + For an overview of these chips see http://www.acerlabs.com + + The M1533/M1543C devices appear as FOUR separate devices + on the PCI bus. An output of lspci will show something similar + to the following: + + 00:02.0 USB Controller: Acer Laboratories Inc. M5237 + 00:03.0 Bridge: Acer Laboratories Inc. M7101 + 00:07.0 ISA bridge: Acer Laboratories Inc. M1533 + 00:0f.0 IDE interface: Acer Laboratories Inc. M5229 + + The SMB controller is part of the 7101 device, which is an + ACPI-compliant Power Management Unit (PMU). + + The whole 7101 device has to be enabled for the SMB to work. + You can't just enable the SMB alone. + The SMB and the ACPI have separate I/O spaces. + We make sure that the SMB is enabled. We leave the ACPI alone. + + This driver controls the SMB Host only. + The SMB Slave controller on the M15X3 is not enabled. + + This driver does not use interrupts. +*/ + +/* Note: we assume there can only be one ALI15X3, with one SMBus interface */ + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/stddef.h> +#include <linux/ioport.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/acpi.h> +#include <linux/io.h> + +/* ALI15X3 SMBus address offsets */ +#define SMBHSTSTS (0 + ali15x3_smba) +#define SMBHSTCNT (1 + ali15x3_smba) +#define SMBHSTSTART (2 + ali15x3_smba) +#define SMBHSTCMD (7 + ali15x3_smba) +#define SMBHSTADD (3 + ali15x3_smba) +#define SMBHSTDAT0 (4 + ali15x3_smba) +#define SMBHSTDAT1 (5 + ali15x3_smba) +#define SMBBLKDAT (6 + ali15x3_smba) + +/* PCI Address Constants */ +#define SMBCOM 0x004 +#define SMBBA 0x014 +#define SMBATPC 0x05B /* used to unlock xxxBA registers */ +#define SMBHSTCFG 0x0E0 +#define SMBSLVC 0x0E1 +#define SMBCLK 0x0E2 +#define SMBREV 0x008 + +/* Other settings */ +#define MAX_TIMEOUT 200 /* times 1/100 sec */ +#define ALI15X3_SMB_IOSIZE 32 + +/* this is what the Award 1004 BIOS sets them to on a ASUS P5A MB. + We don't use these here. If the bases aren't set to some value we + tell user to upgrade BIOS and we fail. +*/ +#define ALI15X3_SMB_DEFAULTBASE 0xE800 + +/* ALI15X3 address lock bits */ +#define ALI15X3_LOCK 0x06 + +/* ALI15X3 command constants */ +#define ALI15X3_ABORT 0x02 +#define ALI15X3_T_OUT 0x04 +#define ALI15X3_QUICK 0x00 +#define ALI15X3_BYTE 0x10 +#define ALI15X3_BYTE_DATA 0x20 +#define ALI15X3_WORD_DATA 0x30 +#define ALI15X3_BLOCK_DATA 0x40 +#define ALI15X3_BLOCK_CLR 0x80 + +/* ALI15X3 status register bits */ +#define ALI15X3_STS_IDLE 0x04 +#define ALI15X3_STS_BUSY 0x08 +#define ALI15X3_STS_DONE 0x10 +#define ALI15X3_STS_DEV 0x20 /* device error */ +#define ALI15X3_STS_COLL 0x40 /* collision or no response */ +#define ALI15X3_STS_TERM 0x80 /* terminated by abort */ +#define ALI15X3_STS_ERR 0xE0 /* all the bad error bits */ + + +/* If force_addr is set to anything different from 0, we forcibly enable + the device at the given address. */ +static u16 force_addr; +module_param_hw(force_addr, ushort, ioport, 0); +MODULE_PARM_DESC(force_addr, + "Initialize the base address of the i2c controller"); + +static struct pci_driver ali15x3_driver; +static unsigned short ali15x3_smba; + +static int ali15x3_setup(struct pci_dev *ALI15X3_dev) +{ + u16 a; + unsigned char temp; + + /* Check the following things: + - SMB I/O address is initialized + - Device is enabled + - We can use the addresses + */ + + /* Unlock the register. + The data sheet says that the address registers are read-only + if the lock bits are 1, but in fact the address registers + are zero unless you clear the lock bits. + */ + pci_read_config_byte(ALI15X3_dev, SMBATPC, &temp); + if (temp & ALI15X3_LOCK) { + temp &= ~ALI15X3_LOCK; + pci_write_config_byte(ALI15X3_dev, SMBATPC, temp); + } + + /* Determine the address of the SMBus area */ + pci_read_config_word(ALI15X3_dev, SMBBA, &ali15x3_smba); + ali15x3_smba &= (0xffff & ~(ALI15X3_SMB_IOSIZE - 1)); + if (ali15x3_smba == 0 && force_addr == 0) { + dev_err(&ALI15X3_dev->dev, "ALI15X3_smb region uninitialized " + "- upgrade BIOS or use force_addr=0xaddr\n"); + return -ENODEV; + } + + if(force_addr) + ali15x3_smba = force_addr & ~(ALI15X3_SMB_IOSIZE - 1); + + if (acpi_check_region(ali15x3_smba, ALI15X3_SMB_IOSIZE, + ali15x3_driver.name)) + return -EBUSY; + + if (!request_region(ali15x3_smba, ALI15X3_SMB_IOSIZE, + ali15x3_driver.name)) { + dev_err(&ALI15X3_dev->dev, + "ALI15X3_smb region 0x%x already in use!\n", + ali15x3_smba); + return -ENODEV; + } + + if(force_addr) { + int ret; + + dev_info(&ALI15X3_dev->dev, "forcing ISA address 0x%04X\n", + ali15x3_smba); + ret = pci_write_config_word(ALI15X3_dev, SMBBA, ali15x3_smba); + if (ret != PCIBIOS_SUCCESSFUL) + goto error; + ret = pci_read_config_word(ALI15X3_dev, SMBBA, &a); + if (ret != PCIBIOS_SUCCESSFUL) + goto error; + if ((a & ~(ALI15X3_SMB_IOSIZE - 1)) != ali15x3_smba) { + /* make sure it works */ + dev_err(&ALI15X3_dev->dev, + "force address failed - not supported?\n"); + goto error; + } + } + /* check if whole device is enabled */ + pci_read_config_byte(ALI15X3_dev, SMBCOM, &temp); + if ((temp & 1) == 0) { + dev_info(&ALI15X3_dev->dev, "enabling SMBus device\n"); + pci_write_config_byte(ALI15X3_dev, SMBCOM, temp | 0x01); + } + + /* Is SMB Host controller enabled? */ + pci_read_config_byte(ALI15X3_dev, SMBHSTCFG, &temp); + if ((temp & 1) == 0) { + dev_info(&ALI15X3_dev->dev, "enabling SMBus controller\n"); + pci_write_config_byte(ALI15X3_dev, SMBHSTCFG, temp | 0x01); + } + + /* set SMB clock to 74KHz as recommended in data sheet */ + pci_write_config_byte(ALI15X3_dev, SMBCLK, 0x20); + + /* + The interrupt routing for SMB is set up in register 0x77 in the + 1533 ISA Bridge device, NOT in the 7101 device. + Don't bother with finding the 1533 device and reading the register. + if ((....... & 0x0F) == 1) + dev_dbg(&ALI15X3_dev->dev, "ALI15X3 using Interrupt 9 for SMBus.\n"); + */ + pci_read_config_byte(ALI15X3_dev, SMBREV, &temp); + dev_dbg(&ALI15X3_dev->dev, "SMBREV = 0x%X\n", temp); + dev_dbg(&ALI15X3_dev->dev, "iALI15X3_smba = 0x%X\n", ali15x3_smba); + + return 0; +error: + release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE); + return -ENODEV; +} + +/* Another internally used function */ +static int ali15x3_transaction(struct i2c_adapter *adap) +{ + int temp; + int result = 0; + int timeout = 0; + + dev_dbg(&adap->dev, "Transaction (pre): STS=%02x, CNT=%02x, CMD=%02x, " + "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS), + inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD), + inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1)); + + /* get status */ + temp = inb_p(SMBHSTSTS); + + /* Make sure the SMBus host is ready to start transmitting */ + /* Check the busy bit first */ + if (temp & ALI15X3_STS_BUSY) { + /* + If the host controller is still busy, it may have timed out in the + previous transaction, resulting in a "SMBus Timeout" Dev. + I've tried the following to reset a stuck busy bit. + 1. Reset the controller with an ABORT command. + (this doesn't seem to clear the controller if an external + device is hung) + 2. Reset the controller and the other SMBus devices with a + T_OUT command. (this clears the host busy bit if an + external device is hung, but it comes back upon a new access + to a device) + 3. Disable and reenable the controller in SMBHSTCFG + Worst case, nothing seems to work except power reset. + */ + /* Abort - reset the host controller */ + /* + Try resetting entire SMB bus, including other devices - + This may not work either - it clears the BUSY bit but + then the BUSY bit may come back on when you try and use the chip again. + If that's the case you are stuck. + */ + dev_info(&adap->dev, "Resetting entire SMB Bus to " + "clear busy condition (%02x)\n", temp); + outb_p(ALI15X3_T_OUT, SMBHSTCNT); + temp = inb_p(SMBHSTSTS); + } + + /* now check the error bits and the busy bit */ + if (temp & (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) { + /* do a clear-on-write */ + outb_p(0xFF, SMBHSTSTS); + if ((temp = inb_p(SMBHSTSTS)) & + (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) { + /* this is probably going to be correctable only by a power reset + as one of the bits now appears to be stuck */ + /* This may be a bus or device with electrical problems. */ + dev_err(&adap->dev, "SMBus reset failed! (0x%02x) - " + "controller or device on bus is probably hung\n", + temp); + return -EBUSY; + } + } else { + /* check and clear done bit */ + if (temp & ALI15X3_STS_DONE) { + outb_p(temp, SMBHSTSTS); + } + } + + /* start the transaction by writing anything to the start register */ + outb_p(0xFF, SMBHSTSTART); + + /* We will always wait for a fraction of a second! */ + timeout = 0; + do { + msleep(1); + temp = inb_p(SMBHSTSTS); + } while ((!(temp & (ALI15X3_STS_ERR | ALI15X3_STS_DONE))) + && (timeout++ < MAX_TIMEOUT)); + + /* If the SMBus is still busy, we give up */ + if (timeout > MAX_TIMEOUT) { + result = -ETIMEDOUT; + dev_err(&adap->dev, "SMBus Timeout!\n"); + } + + if (temp & ALI15X3_STS_TERM) { + result = -EIO; + dev_dbg(&adap->dev, "Error: Failed bus transaction\n"); + } + + /* + Unfortunately the ALI SMB controller maps "no response" and "bus + collision" into a single bit. No response is the usual case so don't + do a printk. + This means that bus collisions go unreported. + */ + if (temp & ALI15X3_STS_COLL) { + result = -ENXIO; + dev_dbg(&adap->dev, + "Error: no response or bus collision ADD=%02x\n", + inb_p(SMBHSTADD)); + } + + /* haven't ever seen this */ + if (temp & ALI15X3_STS_DEV) { + result = -EIO; + dev_err(&adap->dev, "Error: device error\n"); + } + dev_dbg(&adap->dev, "Transaction (post): STS=%02x, CNT=%02x, CMD=%02x, " + "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS), + inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD), + inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1)); + return result; +} + +/* Return negative errno on error. */ +static s32 ali15x3_access(struct i2c_adapter * adap, u16 addr, + unsigned short flags, char read_write, u8 command, + int size, union i2c_smbus_data * data) +{ + int i, len; + int temp; + int timeout; + + /* clear all the bits (clear-on-write) */ + outb_p(0xFF, SMBHSTSTS); + /* make sure SMBus is idle */ + temp = inb_p(SMBHSTSTS); + for (timeout = 0; + (timeout < MAX_TIMEOUT) && !(temp & ALI15X3_STS_IDLE); + timeout++) { + msleep(1); + temp = inb_p(SMBHSTSTS); + } + if (timeout >= MAX_TIMEOUT) { + dev_err(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp); + } + + switch (size) { + case I2C_SMBUS_QUICK: + outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMBHSTADD); + size = ALI15X3_QUICK; + break; + case I2C_SMBUS_BYTE: + outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMBHSTADD); + if (read_write == I2C_SMBUS_WRITE) + outb_p(command, SMBHSTCMD); + size = ALI15X3_BYTE; + break; + case I2C_SMBUS_BYTE_DATA: + outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMBHSTADD); + outb_p(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) + outb_p(data->byte, SMBHSTDAT0); + size = ALI15X3_BYTE_DATA; + break; + case I2C_SMBUS_WORD_DATA: + outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMBHSTADD); + outb_p(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) { + outb_p(data->word & 0xff, SMBHSTDAT0); + outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1); + } + size = ALI15X3_WORD_DATA; + break; + case I2C_SMBUS_BLOCK_DATA: + outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMBHSTADD); + outb_p(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) { + len = data->block[0]; + if (len < 0) { + len = 0; + data->block[0] = len; + } + if (len > 32) { + len = 32; + data->block[0] = len; + } + outb_p(len, SMBHSTDAT0); + /* Reset SMBBLKDAT */ + outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT); + for (i = 1; i <= len; i++) + outb_p(data->block[i], SMBBLKDAT); + } + size = ALI15X3_BLOCK_DATA; + break; + default: + dev_warn(&adap->dev, "Unsupported transaction %d\n", size); + return -EOPNOTSUPP; + } + + outb_p(size, SMBHSTCNT); /* output command */ + + temp = ali15x3_transaction(adap); + if (temp) + return temp; + + if ((read_write == I2C_SMBUS_WRITE) || (size == ALI15X3_QUICK)) + return 0; + + + switch (size) { + case ALI15X3_BYTE: /* Result put in SMBHSTDAT0 */ + data->byte = inb_p(SMBHSTDAT0); + break; + case ALI15X3_BYTE_DATA: + data->byte = inb_p(SMBHSTDAT0); + break; + case ALI15X3_WORD_DATA: + data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8); + break; + case ALI15X3_BLOCK_DATA: + len = inb_p(SMBHSTDAT0); + if (len > 32) + len = 32; + data->block[0] = len; + /* Reset SMBBLKDAT */ + outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT); + for (i = 1; i <= data->block[0]; i++) { + data->block[i] = inb_p(SMBBLKDAT); + dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n", + len, i, data->block[i]); + } + break; + } + return 0; +} + +static u32 ali15x3_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_BLOCK_DATA; +} + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = ali15x3_access, + .functionality = ali15x3_func, +}; + +static struct i2c_adapter ali15x3_adapter = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = &smbus_algorithm, +}; + +static const struct pci_device_id ali15x3_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) }, + { 0, } +}; + +MODULE_DEVICE_TABLE (pci, ali15x3_ids); + +static int ali15x3_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + if (ali15x3_setup(dev)) { + dev_err(&dev->dev, + "ALI15X3 not detected, module not inserted.\n"); + return -ENODEV; + } + + /* set up the sysfs linkage to our parent device */ + ali15x3_adapter.dev.parent = &dev->dev; + + snprintf(ali15x3_adapter.name, sizeof(ali15x3_adapter.name), + "SMBus ALI15X3 adapter at %04x", ali15x3_smba); + return i2c_add_adapter(&ali15x3_adapter); +} + +static void ali15x3_remove(struct pci_dev *dev) +{ + i2c_del_adapter(&ali15x3_adapter); + release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE); +} + +static struct pci_driver ali15x3_driver = { + .name = "ali15x3_smbus", + .id_table = ali15x3_ids, + .probe = ali15x3_probe, + .remove = ali15x3_remove, +}; + +module_pci_driver(ali15x3_driver); + +MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>"); +MODULE_AUTHOR("Philip Edelbrock <phil@netroedge.com>"); +MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>"); +MODULE_DESCRIPTION("ALI15X3 SMBus driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-altera.c b/drivers/i2c/busses/i2c-altera.c new file mode 100644 index 000000000..252fbd175 --- /dev/null +++ b/drivers/i2c/busses/i2c-altera.c @@ -0,0 +1,496 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright Intel Corporation (C) 2017. + * + * Based on the i2c-axxia.c driver. + */ +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/iopoll.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> + +#define ALTR_I2C_TFR_CMD 0x00 /* Transfer Command register */ +#define ALTR_I2C_TFR_CMD_STA BIT(9) /* send START before byte */ +#define ALTR_I2C_TFR_CMD_STO BIT(8) /* send STOP after byte */ +#define ALTR_I2C_TFR_CMD_RW_D BIT(0) /* Direction of transfer */ +#define ALTR_I2C_RX_DATA 0x04 /* RX data FIFO register */ +#define ALTR_I2C_CTRL 0x08 /* Control register */ +#define ALTR_I2C_CTRL_RXT_SHFT 4 /* RX FIFO Threshold */ +#define ALTR_I2C_CTRL_TCT_SHFT 2 /* TFER CMD FIFO Threshold */ +#define ALTR_I2C_CTRL_BSPEED BIT(1) /* Bus Speed (1=Fast) */ +#define ALTR_I2C_CTRL_EN BIT(0) /* Enable Core (1=Enable) */ +#define ALTR_I2C_ISER 0x0C /* Interrupt Status Enable register */ +#define ALTR_I2C_ISER_RXOF_EN BIT(4) /* Enable RX OVERFLOW IRQ */ +#define ALTR_I2C_ISER_ARB_EN BIT(3) /* Enable ARB LOST IRQ */ +#define ALTR_I2C_ISER_NACK_EN BIT(2) /* Enable NACK DET IRQ */ +#define ALTR_I2C_ISER_RXRDY_EN BIT(1) /* Enable RX Ready IRQ */ +#define ALTR_I2C_ISER_TXRDY_EN BIT(0) /* Enable TX Ready IRQ */ +#define ALTR_I2C_ISR 0x10 /* Interrupt Status register */ +#define ALTR_I2C_ISR_RXOF BIT(4) /* RX OVERFLOW IRQ */ +#define ALTR_I2C_ISR_ARB BIT(3) /* ARB LOST IRQ */ +#define ALTR_I2C_ISR_NACK BIT(2) /* NACK DET IRQ */ +#define ALTR_I2C_ISR_RXRDY BIT(1) /* RX Ready IRQ */ +#define ALTR_I2C_ISR_TXRDY BIT(0) /* TX Ready IRQ */ +#define ALTR_I2C_STATUS 0x14 /* Status register */ +#define ALTR_I2C_STAT_CORE BIT(0) /* Core Status (0=idle) */ +#define ALTR_I2C_TC_FIFO_LVL 0x18 /* Transfer FIFO LVL register */ +#define ALTR_I2C_RX_FIFO_LVL 0x1C /* Receive FIFO LVL register */ +#define ALTR_I2C_SCL_LOW 0x20 /* SCL low count register */ +#define ALTR_I2C_SCL_HIGH 0x24 /* SCL high count register */ +#define ALTR_I2C_SDA_HOLD 0x28 /* SDA hold count register */ + +#define ALTR_I2C_ALL_IRQ (ALTR_I2C_ISR_RXOF | ALTR_I2C_ISR_ARB | \ + ALTR_I2C_ISR_NACK | ALTR_I2C_ISR_RXRDY | \ + ALTR_I2C_ISR_TXRDY) + +#define ALTR_I2C_THRESHOLD 0 /* IRQ Threshold at 1 element */ +#define ALTR_I2C_DFLT_FIFO_SZ 4 +#define ALTR_I2C_TIMEOUT 100000 /* 100ms */ +#define ALTR_I2C_XFER_TIMEOUT (msecs_to_jiffies(250)) + +/** + * struct altr_i2c_dev - I2C device context + * @base: pointer to register struct + * @msg: pointer to current message + * @msg_len: number of bytes transferred in msg + * @msg_err: error code for completed message + * @msg_complete: xfer completion object + * @dev: device reference + * @adapter: core i2c abstraction + * @i2c_clk: clock reference for i2c input clock + * @bus_clk_rate: current i2c bus clock rate + * @buf: ptr to msg buffer for easier use. + * @fifo_size: size of the FIFO passed in. + * @isr_mask: cached copy of local ISR enables. + * @isr_status: cached copy of local ISR status. + * @isr_mutex: mutex for IRQ thread. + */ +struct altr_i2c_dev { + void __iomem *base; + struct i2c_msg *msg; + size_t msg_len; + int msg_err; + struct completion msg_complete; + struct device *dev; + struct i2c_adapter adapter; + struct clk *i2c_clk; + u32 bus_clk_rate; + u8 *buf; + u32 fifo_size; + u32 isr_mask; + u32 isr_status; + struct mutex isr_mutex; +}; + +static void +altr_i2c_int_enable(struct altr_i2c_dev *idev, u32 mask, bool enable) +{ + u32 int_en; + + int_en = readl(idev->base + ALTR_I2C_ISER); + if (enable) + idev->isr_mask = int_en | mask; + else + idev->isr_mask = int_en & ~mask; + + writel(idev->isr_mask, idev->base + ALTR_I2C_ISER); +} + +static void altr_i2c_int_clear(struct altr_i2c_dev *idev, u32 mask) +{ + u32 int_en = readl(idev->base + ALTR_I2C_ISR); + + writel(int_en | mask, idev->base + ALTR_I2C_ISR); +} + +static void altr_i2c_core_disable(struct altr_i2c_dev *idev) +{ + u32 tmp = readl(idev->base + ALTR_I2C_CTRL); + + writel(tmp & ~ALTR_I2C_CTRL_EN, idev->base + ALTR_I2C_CTRL); +} + +static void altr_i2c_core_enable(struct altr_i2c_dev *idev) +{ + u32 tmp = readl(idev->base + ALTR_I2C_CTRL); + + writel(tmp | ALTR_I2C_CTRL_EN, idev->base + ALTR_I2C_CTRL); +} + +static void altr_i2c_reset(struct altr_i2c_dev *idev) +{ + altr_i2c_core_disable(idev); + altr_i2c_core_enable(idev); +} + +static inline void altr_i2c_stop(struct altr_i2c_dev *idev) +{ + writel(ALTR_I2C_TFR_CMD_STO, idev->base + ALTR_I2C_TFR_CMD); +} + +static void altr_i2c_init(struct altr_i2c_dev *idev) +{ + u32 divisor = clk_get_rate(idev->i2c_clk) / idev->bus_clk_rate; + u32 clk_mhz = clk_get_rate(idev->i2c_clk) / 1000000; + u32 tmp = (ALTR_I2C_THRESHOLD << ALTR_I2C_CTRL_RXT_SHFT) | + (ALTR_I2C_THRESHOLD << ALTR_I2C_CTRL_TCT_SHFT); + u32 t_high, t_low; + + if (idev->bus_clk_rate <= I2C_MAX_STANDARD_MODE_FREQ) { + tmp &= ~ALTR_I2C_CTRL_BSPEED; + /* Standard mode SCL 50/50 */ + t_high = divisor * 1 / 2; + t_low = divisor * 1 / 2; + } else { + tmp |= ALTR_I2C_CTRL_BSPEED; + /* Fast mode SCL 33/66 */ + t_high = divisor * 1 / 3; + t_low = divisor * 2 / 3; + } + writel(tmp, idev->base + ALTR_I2C_CTRL); + + dev_dbg(idev->dev, "rate=%uHz per_clk=%uMHz -> ratio=1:%u\n", + idev->bus_clk_rate, clk_mhz, divisor); + + /* Reset controller */ + altr_i2c_reset(idev); + + /* SCL High Time */ + writel(t_high, idev->base + ALTR_I2C_SCL_HIGH); + /* SCL Low Time */ + writel(t_low, idev->base + ALTR_I2C_SCL_LOW); + /* SDA Hold Time, 300ns */ + writel(3 * clk_mhz / 10, idev->base + ALTR_I2C_SDA_HOLD); + + /* Mask all master interrupt bits */ + altr_i2c_int_enable(idev, ALTR_I2C_ALL_IRQ, false); +} + +/* + * altr_i2c_transfer - On the last byte to be transmitted, send + * a Stop bit on the last byte. + */ +static void altr_i2c_transfer(struct altr_i2c_dev *idev, u32 data) +{ + /* On the last byte to be transmitted, send STOP */ + if (idev->msg_len == 1) + data |= ALTR_I2C_TFR_CMD_STO; + if (idev->msg_len > 0) + writel(data, idev->base + ALTR_I2C_TFR_CMD); +} + +/* + * altr_i2c_empty_rx_fifo - Fetch data from RX FIFO until end of + * transfer. Send a Stop bit on the last byte. + */ +static void altr_i2c_empty_rx_fifo(struct altr_i2c_dev *idev) +{ + size_t rx_fifo_avail = readl(idev->base + ALTR_I2C_RX_FIFO_LVL); + int bytes_to_transfer = min(rx_fifo_avail, idev->msg_len); + + while (bytes_to_transfer-- > 0) { + *idev->buf++ = readl(idev->base + ALTR_I2C_RX_DATA); + idev->msg_len--; + altr_i2c_transfer(idev, 0); + } +} + +/* + * altr_i2c_fill_tx_fifo - Fill TX FIFO from current message buffer. + */ +static int altr_i2c_fill_tx_fifo(struct altr_i2c_dev *idev) +{ + size_t tx_fifo_avail = idev->fifo_size - readl(idev->base + + ALTR_I2C_TC_FIFO_LVL); + int bytes_to_transfer = min(tx_fifo_avail, idev->msg_len); + int ret = idev->msg_len - bytes_to_transfer; + + while (bytes_to_transfer-- > 0) { + altr_i2c_transfer(idev, *idev->buf++); + idev->msg_len--; + } + + return ret; +} + +static irqreturn_t altr_i2c_isr_quick(int irq, void *_dev) +{ + struct altr_i2c_dev *idev = _dev; + irqreturn_t ret = IRQ_HANDLED; + + /* Read IRQ status but only interested in Enabled IRQs. */ + idev->isr_status = readl(idev->base + ALTR_I2C_ISR) & idev->isr_mask; + if (idev->isr_status) + ret = IRQ_WAKE_THREAD; + + return ret; +} + +static irqreturn_t altr_i2c_isr(int irq, void *_dev) +{ + int ret; + bool read, finish = false; + struct altr_i2c_dev *idev = _dev; + u32 status = idev->isr_status; + + mutex_lock(&idev->isr_mutex); + if (!idev->msg) { + dev_warn(idev->dev, "unexpected interrupt\n"); + altr_i2c_int_clear(idev, ALTR_I2C_ALL_IRQ); + goto out; + } + read = (idev->msg->flags & I2C_M_RD) != 0; + + /* handle Lost Arbitration */ + if (unlikely(status & ALTR_I2C_ISR_ARB)) { + altr_i2c_int_clear(idev, ALTR_I2C_ISR_ARB); + idev->msg_err = -EAGAIN; + finish = true; + } else if (unlikely(status & ALTR_I2C_ISR_NACK)) { + dev_dbg(idev->dev, "Could not get ACK\n"); + idev->msg_err = -ENXIO; + altr_i2c_int_clear(idev, ALTR_I2C_ISR_NACK); + altr_i2c_stop(idev); + finish = true; + } else if (read && unlikely(status & ALTR_I2C_ISR_RXOF)) { + /* handle RX FIFO Overflow */ + altr_i2c_empty_rx_fifo(idev); + altr_i2c_int_clear(idev, ALTR_I2C_ISR_RXRDY); + altr_i2c_stop(idev); + dev_err(idev->dev, "RX FIFO Overflow\n"); + finish = true; + } else if (read && (status & ALTR_I2C_ISR_RXRDY)) { + /* RX FIFO needs service? */ + altr_i2c_empty_rx_fifo(idev); + altr_i2c_int_clear(idev, ALTR_I2C_ISR_RXRDY); + if (!idev->msg_len) + finish = true; + } else if (!read && (status & ALTR_I2C_ISR_TXRDY)) { + /* TX FIFO needs service? */ + altr_i2c_int_clear(idev, ALTR_I2C_ISR_TXRDY); + if (idev->msg_len > 0) + altr_i2c_fill_tx_fifo(idev); + else + finish = true; + } else { + dev_warn(idev->dev, "Unexpected interrupt: 0x%x\n", status); + altr_i2c_int_clear(idev, ALTR_I2C_ALL_IRQ); + } + + if (finish) { + /* Wait for the Core to finish */ + ret = readl_poll_timeout_atomic(idev->base + ALTR_I2C_STATUS, + status, + !(status & ALTR_I2C_STAT_CORE), + 1, ALTR_I2C_TIMEOUT); + if (ret) + dev_err(idev->dev, "message timeout\n"); + altr_i2c_int_enable(idev, ALTR_I2C_ALL_IRQ, false); + altr_i2c_int_clear(idev, ALTR_I2C_ALL_IRQ); + complete(&idev->msg_complete); + dev_dbg(idev->dev, "Message Complete\n"); + } +out: + mutex_unlock(&idev->isr_mutex); + + return IRQ_HANDLED; +} + +static int altr_i2c_xfer_msg(struct altr_i2c_dev *idev, struct i2c_msg *msg) +{ + u32 imask = ALTR_I2C_ISR_RXOF | ALTR_I2C_ISR_ARB | ALTR_I2C_ISR_NACK; + unsigned long time_left; + u32 value; + u8 addr = i2c_8bit_addr_from_msg(msg); + + mutex_lock(&idev->isr_mutex); + idev->msg = msg; + idev->msg_len = msg->len; + idev->buf = msg->buf; + idev->msg_err = 0; + reinit_completion(&idev->msg_complete); + altr_i2c_core_enable(idev); + + /* Make sure RX FIFO is empty */ + do { + readl(idev->base + ALTR_I2C_RX_DATA); + } while (readl(idev->base + ALTR_I2C_RX_FIFO_LVL)); + + writel(ALTR_I2C_TFR_CMD_STA | addr, idev->base + ALTR_I2C_TFR_CMD); + + if ((msg->flags & I2C_M_RD) != 0) { + imask |= ALTR_I2C_ISER_RXOF_EN | ALTR_I2C_ISER_RXRDY_EN; + altr_i2c_int_enable(idev, imask, true); + /* write the first byte to start the RX */ + altr_i2c_transfer(idev, 0); + } else { + imask |= ALTR_I2C_ISR_TXRDY; + altr_i2c_int_enable(idev, imask, true); + altr_i2c_fill_tx_fifo(idev); + } + mutex_unlock(&idev->isr_mutex); + + time_left = wait_for_completion_timeout(&idev->msg_complete, + ALTR_I2C_XFER_TIMEOUT); + mutex_lock(&idev->isr_mutex); + altr_i2c_int_enable(idev, imask, false); + + value = readl(idev->base + ALTR_I2C_STATUS) & ALTR_I2C_STAT_CORE; + if (value) + dev_err(idev->dev, "Core Status not IDLE...\n"); + + if (time_left == 0) { + idev->msg_err = -ETIMEDOUT; + dev_dbg(idev->dev, "Transaction timed out.\n"); + } + + altr_i2c_core_disable(idev); + mutex_unlock(&idev->isr_mutex); + + return idev->msg_err; +} + +static int +altr_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + struct altr_i2c_dev *idev = i2c_get_adapdata(adap); + int i, ret; + + for (i = 0; i < num; i++) { + ret = altr_i2c_xfer_msg(idev, msgs++); + if (ret) + return ret; + } + return num; +} + +static u32 altr_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm altr_i2c_algo = { + .master_xfer = altr_i2c_xfer, + .functionality = altr_i2c_func, +}; + +static int altr_i2c_probe(struct platform_device *pdev) +{ + struct altr_i2c_dev *idev = NULL; + int irq, ret; + + idev = devm_kzalloc(&pdev->dev, sizeof(*idev), GFP_KERNEL); + if (!idev) + return -ENOMEM; + + idev->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(idev->base)) + return PTR_ERR(idev->base); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + idev->i2c_clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(idev->i2c_clk)) { + dev_err(&pdev->dev, "missing clock\n"); + return PTR_ERR(idev->i2c_clk); + } + + idev->dev = &pdev->dev; + init_completion(&idev->msg_complete); + mutex_init(&idev->isr_mutex); + + ret = device_property_read_u32(idev->dev, "fifo-size", + &idev->fifo_size); + if (ret) { + dev_err(&pdev->dev, "FIFO size set to default of %d\n", + ALTR_I2C_DFLT_FIFO_SZ); + idev->fifo_size = ALTR_I2C_DFLT_FIFO_SZ; + } + + ret = device_property_read_u32(idev->dev, "clock-frequency", + &idev->bus_clk_rate); + if (ret) { + dev_err(&pdev->dev, "Default to 100kHz\n"); + idev->bus_clk_rate = I2C_MAX_STANDARD_MODE_FREQ; /* default clock rate */ + } + + if (idev->bus_clk_rate > I2C_MAX_FAST_MODE_FREQ) { + dev_err(&pdev->dev, "invalid clock-frequency %d\n", + idev->bus_clk_rate); + return -EINVAL; + } + + ret = devm_request_threaded_irq(&pdev->dev, irq, altr_i2c_isr_quick, + altr_i2c_isr, IRQF_ONESHOT, + pdev->name, idev); + if (ret) { + dev_err(&pdev->dev, "failed to claim IRQ %d\n", irq); + return ret; + } + + ret = clk_prepare_enable(idev->i2c_clk); + if (ret) { + dev_err(&pdev->dev, "failed to enable clock\n"); + return ret; + } + + mutex_lock(&idev->isr_mutex); + altr_i2c_init(idev); + mutex_unlock(&idev->isr_mutex); + + i2c_set_adapdata(&idev->adapter, idev); + strscpy(idev->adapter.name, pdev->name, sizeof(idev->adapter.name)); + idev->adapter.owner = THIS_MODULE; + idev->adapter.algo = &altr_i2c_algo; + idev->adapter.dev.parent = &pdev->dev; + idev->adapter.dev.of_node = pdev->dev.of_node; + + platform_set_drvdata(pdev, idev); + + ret = i2c_add_adapter(&idev->adapter); + if (ret) { + clk_disable_unprepare(idev->i2c_clk); + return ret; + } + dev_info(&pdev->dev, "Altera SoftIP I2C Probe Complete\n"); + + return 0; +} + +static void altr_i2c_remove(struct platform_device *pdev) +{ + struct altr_i2c_dev *idev = platform_get_drvdata(pdev); + + clk_disable_unprepare(idev->i2c_clk); + i2c_del_adapter(&idev->adapter); +} + +/* Match table for of_platform binding */ +static const struct of_device_id altr_i2c_of_match[] = { + { .compatible = "altr,softip-i2c-v1.0" }, + {}, +}; +MODULE_DEVICE_TABLE(of, altr_i2c_of_match); + +static struct platform_driver altr_i2c_driver = { + .probe = altr_i2c_probe, + .remove_new = altr_i2c_remove, + .driver = { + .name = "altera-i2c", + .of_match_table = altr_i2c_of_match, + }, +}; + +module_platform_driver(altr_i2c_driver); + +MODULE_DESCRIPTION("Altera Soft IP I2C bus driver"); +MODULE_AUTHOR("Thor Thayer <thor.thayer@linux.intel.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-amd-mp2-pci.c b/drivers/i2c/busses/i2c-amd-mp2-pci.c new file mode 100644 index 000000000..143165300 --- /dev/null +++ b/drivers/i2c/busses/i2c-amd-mp2-pci.c @@ -0,0 +1,477 @@ +// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause +/* + * AMD MP2 PCIe communication driver + * + * Authors: Shyam Sundar S K <Shyam-sundar.S-k@amd.com> + * Elie Morisse <syniurge@gmail.com> + */ + +#include <linux/dma-mapping.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/slab.h> + +#include "i2c-amd-mp2.h" + +#include <linux/io-64-nonatomic-lo-hi.h> + +static void amd_mp2_c2p_mutex_lock(struct amd_i2c_common *i2c_common) +{ + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; + + /* there is only one data mailbox for two i2c adapters */ + mutex_lock(&privdata->c2p_lock); + privdata->c2p_lock_busid = i2c_common->bus_id; +} + +static void amd_mp2_c2p_mutex_unlock(struct amd_i2c_common *i2c_common) +{ + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; + + if (unlikely(privdata->c2p_lock_busid != i2c_common->bus_id)) { + pci_warn(privdata->pci_dev, + "bus %d attempting to unlock C2P locked by bus %d\n", + i2c_common->bus_id, privdata->c2p_lock_busid); + return; + } + + mutex_unlock(&privdata->c2p_lock); +} + +static int amd_mp2_cmd(struct amd_i2c_common *i2c_common, + union i2c_cmd_base i2c_cmd_base) +{ + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; + void __iomem *reg; + + i2c_common->reqcmd = i2c_cmd_base.s.i2c_cmd; + + reg = privdata->mmio + ((i2c_cmd_base.s.bus_id == 1) ? + AMD_C2P_MSG1 : AMD_C2P_MSG0); + writel(i2c_cmd_base.ul, reg); + + return 0; +} + +int amd_mp2_bus_enable_set(struct amd_i2c_common *i2c_common, bool enable) +{ + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; + union i2c_cmd_base i2c_cmd_base; + + pci_dbg(privdata->pci_dev, "id: %d\n", i2c_common->bus_id); + + i2c_cmd_base.ul = 0; + i2c_cmd_base.s.i2c_cmd = enable ? i2c_enable : i2c_disable; + i2c_cmd_base.s.bus_id = i2c_common->bus_id; + i2c_cmd_base.s.i2c_speed = i2c_common->i2c_speed; + + amd_mp2_c2p_mutex_lock(i2c_common); + + return amd_mp2_cmd(i2c_common, i2c_cmd_base); +} +EXPORT_SYMBOL_GPL(amd_mp2_bus_enable_set); + +static void amd_mp2_cmd_rw_fill(struct amd_i2c_common *i2c_common, + union i2c_cmd_base *i2c_cmd_base, + enum i2c_cmd reqcmd) +{ + i2c_cmd_base->s.i2c_cmd = reqcmd; + i2c_cmd_base->s.bus_id = i2c_common->bus_id; + i2c_cmd_base->s.i2c_speed = i2c_common->i2c_speed; + i2c_cmd_base->s.slave_addr = i2c_common->msg->addr; + i2c_cmd_base->s.length = i2c_common->msg->len; +} + +int amd_mp2_rw(struct amd_i2c_common *i2c_common, enum i2c_cmd reqcmd) +{ + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; + union i2c_cmd_base i2c_cmd_base; + + amd_mp2_cmd_rw_fill(i2c_common, &i2c_cmd_base, reqcmd); + amd_mp2_c2p_mutex_lock(i2c_common); + + if (i2c_common->msg->len <= 32) { + i2c_cmd_base.s.mem_type = use_c2pmsg; + if (reqcmd == i2c_write) + memcpy_toio(privdata->mmio + AMD_C2P_MSG2, + i2c_common->msg->buf, + i2c_common->msg->len); + } else { + i2c_cmd_base.s.mem_type = use_dram; + writeq((u64)i2c_common->dma_addr, + privdata->mmio + AMD_C2P_MSG2); + } + + return amd_mp2_cmd(i2c_common, i2c_cmd_base); +} +EXPORT_SYMBOL_GPL(amd_mp2_rw); + +static void amd_mp2_pci_check_rw_event(struct amd_i2c_common *i2c_common) +{ + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; + struct pci_dev *pdev = privdata->pci_dev; + int len = i2c_common->eventval.r.length; + u32 slave_addr = i2c_common->eventval.r.slave_addr; + bool err = false; + + if (unlikely(len != i2c_common->msg->len)) { + pci_err(pdev, "length %d in event doesn't match buffer length %d!\n", + len, i2c_common->msg->len); + err = true; + } + + if (unlikely(slave_addr != i2c_common->msg->addr)) { + pci_err(pdev, "unexpected slave address %x (expected: %x)!\n", + slave_addr, i2c_common->msg->addr); + err = true; + } + + if (!err) + i2c_common->cmd_success = true; +} + +static void __amd_mp2_process_event(struct amd_i2c_common *i2c_common) +{ + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; + struct pci_dev *pdev = privdata->pci_dev; + enum status_type sts = i2c_common->eventval.r.status; + enum response_type res = i2c_common->eventval.r.response; + int len = i2c_common->eventval.r.length; + + if (res != command_success) { + if (res != command_failed) + pci_err(pdev, "invalid response to i2c command!\n"); + return; + } + + switch (i2c_common->reqcmd) { + case i2c_read: + if (sts == i2c_readcomplete_event) { + amd_mp2_pci_check_rw_event(i2c_common); + if (len <= 32) + memcpy_fromio(i2c_common->msg->buf, + privdata->mmio + AMD_C2P_MSG2, + len); + } else if (sts != i2c_readfail_event) { + pci_err(pdev, "invalid i2c status after read (%d)!\n", sts); + } + break; + case i2c_write: + if (sts == i2c_writecomplete_event) + amd_mp2_pci_check_rw_event(i2c_common); + else if (sts != i2c_writefail_event) + pci_err(pdev, "invalid i2c status after write (%d)!\n", sts); + break; + case i2c_enable: + if (sts == i2c_busenable_complete) + i2c_common->cmd_success = true; + else if (sts != i2c_busenable_failed) + pci_err(pdev, "invalid i2c status after bus enable (%d)!\n", sts); + break; + case i2c_disable: + if (sts == i2c_busdisable_complete) + i2c_common->cmd_success = true; + else if (sts != i2c_busdisable_failed) + pci_err(pdev, "invalid i2c status after bus disable (%d)!\n", sts); + break; + default: + break; + } +} + +void amd_mp2_process_event(struct amd_i2c_common *i2c_common) +{ + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; + struct pci_dev *pdev = privdata->pci_dev; + + if (unlikely(i2c_common->reqcmd == i2c_none)) { + pci_warn(pdev, "received msg but no cmd was sent (bus = %d)!\n", + i2c_common->bus_id); + return; + } + + __amd_mp2_process_event(i2c_common); + + i2c_common->reqcmd = i2c_none; + amd_mp2_c2p_mutex_unlock(i2c_common); +} +EXPORT_SYMBOL_GPL(amd_mp2_process_event); + +static irqreturn_t amd_mp2_irq_isr(int irq, void *dev) +{ + struct amd_mp2_dev *privdata = dev; + struct pci_dev *pdev = privdata->pci_dev; + struct amd_i2c_common *i2c_common; + u32 val; + unsigned int bus_id; + void __iomem *reg; + enum irqreturn ret = IRQ_NONE; + + for (bus_id = 0; bus_id < 2; bus_id++) { + i2c_common = privdata->busses[bus_id]; + if (!i2c_common) + continue; + + reg = privdata->mmio + ((bus_id == 0) ? + AMD_P2C_MSG1 : AMD_P2C_MSG2); + val = readl(reg); + if (val != 0) { + writel(0, reg); + writel(0, privdata->mmio + AMD_P2C_MSG_INTEN); + i2c_common->eventval.ul = val; + i2c_common->cmd_completion(i2c_common); + + ret = IRQ_HANDLED; + } + } + + if (ret != IRQ_HANDLED) { + val = readl(privdata->mmio + AMD_P2C_MSG_INTEN); + if (val != 0) { + writel(0, privdata->mmio + AMD_P2C_MSG_INTEN); + pci_warn(pdev, "received irq without message\n"); + ret = IRQ_HANDLED; + } + } + + return ret; +} + +void amd_mp2_rw_timeout(struct amd_i2c_common *i2c_common) +{ + i2c_common->reqcmd = i2c_none; + amd_mp2_c2p_mutex_unlock(i2c_common); +} +EXPORT_SYMBOL_GPL(amd_mp2_rw_timeout); + +int amd_mp2_register_cb(struct amd_i2c_common *i2c_common) +{ + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; + struct pci_dev *pdev = privdata->pci_dev; + + if (i2c_common->bus_id > 1) + return -EINVAL; + + if (privdata->busses[i2c_common->bus_id]) { + pci_err(pdev, "Bus %d already taken!\n", i2c_common->bus_id); + return -EINVAL; + } + + privdata->busses[i2c_common->bus_id] = i2c_common; + + return 0; +} +EXPORT_SYMBOL_GPL(amd_mp2_register_cb); + +int amd_mp2_unregister_cb(struct amd_i2c_common *i2c_common) +{ + struct amd_mp2_dev *privdata = i2c_common->mp2_dev; + + privdata->busses[i2c_common->bus_id] = NULL; + + return 0; +} +EXPORT_SYMBOL_GPL(amd_mp2_unregister_cb); + +static void amd_mp2_clear_reg(struct amd_mp2_dev *privdata) +{ + int reg; + + for (reg = AMD_C2P_MSG0; reg <= AMD_C2P_MSG9; reg += 4) + writel(0, privdata->mmio + reg); + + for (reg = AMD_P2C_MSG1; reg <= AMD_P2C_MSG2; reg += 4) + writel(0, privdata->mmio + reg); +} + +static int amd_mp2_pci_init(struct amd_mp2_dev *privdata, + struct pci_dev *pci_dev) +{ + int irq_flag = 0, rc; + + pci_set_drvdata(pci_dev, privdata); + + rc = pcim_enable_device(pci_dev); + if (rc) { + pci_err(pci_dev, "Failed to enable MP2 PCI device\n"); + goto err_pci_enable; + } + + rc = pcim_iomap_regions(pci_dev, 1 << 2, pci_name(pci_dev)); + if (rc) { + pci_err(pci_dev, "I/O memory remapping failed\n"); + goto err_pci_enable; + } + privdata->mmio = pcim_iomap_table(pci_dev)[2]; + + pci_set_master(pci_dev); + + rc = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(64)); + if (rc) + goto err_dma_mask; + + /* request and enable interrupt */ + writel(0, privdata->mmio + AMD_P2C_MSG_INTEN); + rc = pci_alloc_irq_vectors(pci_dev, 1, 1, PCI_IRQ_ALL_TYPES); + if (rc < 0) { + dev_err(&pci_dev->dev, "Failed to allocate single IRQ err=%d\n", rc); + goto err_dma_mask; + } + + privdata->dev_irq = pci_irq_vector(pci_dev, 0); + if (!pci_dev->msix_enabled && !pci_dev->msi_enabled) + irq_flag = IRQF_SHARED; + + rc = devm_request_irq(&pci_dev->dev, privdata->dev_irq, + amd_mp2_irq_isr, irq_flag, dev_name(&pci_dev->dev), privdata); + if (rc) { + pci_err(pci_dev, "Failure requesting irq %i: %d\n", privdata->dev_irq, rc); + goto free_irq_vectors; + } + + return rc; + +free_irq_vectors: + free_irq(privdata->dev_irq, privdata); +err_dma_mask: + pci_clear_master(pci_dev); +err_pci_enable: + pci_set_drvdata(pci_dev, NULL); + return rc; +} + +static int amd_mp2_pci_probe(struct pci_dev *pci_dev, + const struct pci_device_id *id) +{ + struct amd_mp2_dev *privdata; + int rc; + + privdata = devm_kzalloc(&pci_dev->dev, sizeof(*privdata), GFP_KERNEL); + if (!privdata) + return -ENOMEM; + + privdata->pci_dev = pci_dev; + rc = amd_mp2_pci_init(privdata, pci_dev); + if (rc) + return rc; + + mutex_init(&privdata->c2p_lock); + + pm_runtime_set_autosuspend_delay(&pci_dev->dev, 1000); + pm_runtime_use_autosuspend(&pci_dev->dev); + pm_runtime_put_autosuspend(&pci_dev->dev); + pm_runtime_allow(&pci_dev->dev); + + privdata->probed = true; + + pci_info(pci_dev, "MP2 device registered.\n"); + return 0; +} + +static void amd_mp2_pci_remove(struct pci_dev *pci_dev) +{ + struct amd_mp2_dev *privdata = pci_get_drvdata(pci_dev); + + pm_runtime_forbid(&pci_dev->dev); + pm_runtime_get_noresume(&pci_dev->dev); + + free_irq(privdata->dev_irq, privdata); + pci_clear_master(pci_dev); + + amd_mp2_clear_reg(privdata); +} + +#ifdef CONFIG_PM +static int amd_mp2_pci_suspend(struct device *dev) +{ + struct pci_dev *pci_dev = to_pci_dev(dev); + struct amd_mp2_dev *privdata = pci_get_drvdata(pci_dev); + struct amd_i2c_common *i2c_common; + unsigned int bus_id; + int ret = 0; + + for (bus_id = 0; bus_id < 2; bus_id++) { + i2c_common = privdata->busses[bus_id]; + if (i2c_common) + i2c_common->suspend(i2c_common); + } + + ret = pci_save_state(pci_dev); + if (ret) { + pci_err(pci_dev, "pci_save_state failed = %d\n", ret); + return ret; + } + + pci_disable_device(pci_dev); + return ret; +} + +static int amd_mp2_pci_resume(struct device *dev) +{ + struct pci_dev *pci_dev = to_pci_dev(dev); + struct amd_mp2_dev *privdata = pci_get_drvdata(pci_dev); + struct amd_i2c_common *i2c_common; + unsigned int bus_id; + int ret = 0; + + pci_restore_state(pci_dev); + ret = pci_enable_device(pci_dev); + if (ret < 0) { + pci_err(pci_dev, "pci_enable_device failed = %d\n", ret); + return ret; + } + + for (bus_id = 0; bus_id < 2; bus_id++) { + i2c_common = privdata->busses[bus_id]; + if (i2c_common) { + ret = i2c_common->resume(i2c_common); + if (ret < 0) + return ret; + } + } + + return ret; +} + +static UNIVERSAL_DEV_PM_OPS(amd_mp2_pci_pm_ops, amd_mp2_pci_suspend, + amd_mp2_pci_resume, NULL); +#endif /* CONFIG_PM */ + +static const struct pci_device_id amd_mp2_pci_tbl[] = { + {PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_MP2)}, + {0} +}; +MODULE_DEVICE_TABLE(pci, amd_mp2_pci_tbl); + +static struct pci_driver amd_mp2_pci_driver = { + .name = "i2c_amd_mp2", + .id_table = amd_mp2_pci_tbl, + .probe = amd_mp2_pci_probe, + .remove = amd_mp2_pci_remove, +#ifdef CONFIG_PM + .driver = { + .pm = &amd_mp2_pci_pm_ops, + }, +#endif +}; +module_pci_driver(amd_mp2_pci_driver); + +struct amd_mp2_dev *amd_mp2_find_device(void) +{ + struct device *dev; + struct pci_dev *pci_dev; + + dev = driver_find_next_device(&amd_mp2_pci_driver.driver, NULL); + if (!dev) + return NULL; + + pci_dev = to_pci_dev(dev); + return (struct amd_mp2_dev *)pci_get_drvdata(pci_dev); +} +EXPORT_SYMBOL_GPL(amd_mp2_find_device); + +MODULE_DESCRIPTION("AMD(R) PCI-E MP2 I2C Controller Driver"); +MODULE_AUTHOR("Shyam Sundar S K <Shyam-sundar.S-k@amd.com>"); +MODULE_AUTHOR("Elie Morisse <syniurge@gmail.com>"); +MODULE_LICENSE("Dual BSD/GPL"); diff --git a/drivers/i2c/busses/i2c-amd-mp2-plat.c b/drivers/i2c/busses/i2c-amd-mp2-plat.c new file mode 100644 index 000000000..112fe2bc5 --- /dev/null +++ b/drivers/i2c/busses/i2c-amd-mp2-plat.c @@ -0,0 +1,360 @@ +// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause +/* + * AMD MP2 platform driver + * + * Setup the I2C adapters enumerated in the ACPI namespace. + * MP2 controllers have 2 separate busses, up to 2 I2C adapters may be listed. + * + * Authors: Nehal Bakulchandra Shah <Nehal-bakulchandra.shah@amd.com> + * Elie Morisse <syniurge@gmail.com> + */ + +#include <linux/acpi.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/types.h> + +#include "i2c-amd-mp2.h" + +#define AMD_MP2_I2C_MAX_RW_LENGTH ((1 << 12) - 1) +#define AMD_I2C_TIMEOUT (msecs_to_jiffies(250)) + +/** + * struct amd_i2c_dev - MP2 bus/i2c adapter context + * @common: shared context with the MP2 PCI driver + * @pdev: platform driver node + * @adap: i2c adapter + * @cmd_complete: xfer completion object + */ +struct amd_i2c_dev { + struct amd_i2c_common common; + struct platform_device *pdev; + struct i2c_adapter adap; + struct completion cmd_complete; +}; + +#define amd_i2c_dev_common(__common) \ + container_of(__common, struct amd_i2c_dev, common) + +static int i2c_amd_dma_map(struct amd_i2c_common *i2c_common) +{ + struct device *dev_pci = &i2c_common->mp2_dev->pci_dev->dev; + struct amd_i2c_dev *i2c_dev = amd_i2c_dev_common(i2c_common); + enum dma_data_direction dma_direction = + i2c_common->msg->flags & I2C_M_RD ? + DMA_FROM_DEVICE : DMA_TO_DEVICE; + + i2c_common->dma_buf = i2c_get_dma_safe_msg_buf(i2c_common->msg, 0); + i2c_common->dma_addr = dma_map_single(dev_pci, i2c_common->dma_buf, + i2c_common->msg->len, + dma_direction); + + if (unlikely(dma_mapping_error(dev_pci, i2c_common->dma_addr))) { + dev_err(&i2c_dev->pdev->dev, + "Error while mapping dma buffer %p\n", + i2c_common->dma_buf); + return -EIO; + } + + return 0; +} + +static void i2c_amd_dma_unmap(struct amd_i2c_common *i2c_common) +{ + struct device *dev_pci = &i2c_common->mp2_dev->pci_dev->dev; + enum dma_data_direction dma_direction = + i2c_common->msg->flags & I2C_M_RD ? + DMA_FROM_DEVICE : DMA_TO_DEVICE; + + dma_unmap_single(dev_pci, i2c_common->dma_addr, + i2c_common->msg->len, dma_direction); + + i2c_put_dma_safe_msg_buf(i2c_common->dma_buf, i2c_common->msg, true); +} + +static void i2c_amd_start_cmd(struct amd_i2c_dev *i2c_dev) +{ + struct amd_i2c_common *i2c_common = &i2c_dev->common; + + reinit_completion(&i2c_dev->cmd_complete); + i2c_common->cmd_success = false; +} + +static void i2c_amd_cmd_completion(struct amd_i2c_common *i2c_common) +{ + struct amd_i2c_dev *i2c_dev = amd_i2c_dev_common(i2c_common); + union i2c_event *event = &i2c_common->eventval; + + if (event->r.status == i2c_readcomplete_event) + dev_dbg(&i2c_dev->pdev->dev, "readdata:%*ph\n", event->r.length, + i2c_common->msg->buf); + + complete(&i2c_dev->cmd_complete); +} + +static int i2c_amd_check_cmd_completion(struct amd_i2c_dev *i2c_dev) +{ + struct amd_i2c_common *i2c_common = &i2c_dev->common; + unsigned long timeout; + + timeout = wait_for_completion_timeout(&i2c_dev->cmd_complete, + i2c_dev->adap.timeout); + + if ((i2c_common->reqcmd == i2c_read || + i2c_common->reqcmd == i2c_write) && + i2c_common->msg->len > 32) + i2c_amd_dma_unmap(i2c_common); + + if (timeout == 0) { + amd_mp2_rw_timeout(i2c_common); + return -ETIMEDOUT; + } + + amd_mp2_process_event(i2c_common); + + if (!i2c_common->cmd_success) + return -EIO; + + return 0; +} + +static int i2c_amd_enable_set(struct amd_i2c_dev *i2c_dev, bool enable) +{ + struct amd_i2c_common *i2c_common = &i2c_dev->common; + + i2c_amd_start_cmd(i2c_dev); + amd_mp2_bus_enable_set(i2c_common, enable); + + return i2c_amd_check_cmd_completion(i2c_dev); +} + +static int i2c_amd_xfer_msg(struct amd_i2c_dev *i2c_dev, struct i2c_msg *pmsg) +{ + struct amd_i2c_common *i2c_common = &i2c_dev->common; + + i2c_amd_start_cmd(i2c_dev); + i2c_common->msg = pmsg; + + if (pmsg->len > 32) + if (i2c_amd_dma_map(i2c_common)) + return -EIO; + + if (pmsg->flags & I2C_M_RD) + amd_mp2_rw(i2c_common, i2c_read); + else + amd_mp2_rw(i2c_common, i2c_write); + + return i2c_amd_check_cmd_completion(i2c_dev); +} + +static int i2c_amd_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + struct amd_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + int i; + struct i2c_msg *pmsg; + int err = 0; + + /* the adapter might have been deleted while waiting for the bus lock */ + if (unlikely(!i2c_dev->common.mp2_dev)) + return -EINVAL; + + amd_mp2_pm_runtime_get(i2c_dev->common.mp2_dev); + + for (i = 0; i < num; i++) { + pmsg = &msgs[i]; + err = i2c_amd_xfer_msg(i2c_dev, pmsg); + if (err) + break; + } + + amd_mp2_pm_runtime_put(i2c_dev->common.mp2_dev); + return err ? err : num; +} + +static u32 i2c_amd_func(struct i2c_adapter *a) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm i2c_amd_algorithm = { + .master_xfer = i2c_amd_xfer, + .functionality = i2c_amd_func, +}; + +#ifdef CONFIG_PM +static int i2c_amd_suspend(struct amd_i2c_common *i2c_common) +{ + struct amd_i2c_dev *i2c_dev = amd_i2c_dev_common(i2c_common); + + i2c_amd_enable_set(i2c_dev, false); + return 0; +} + +static int i2c_amd_resume(struct amd_i2c_common *i2c_common) +{ + struct amd_i2c_dev *i2c_dev = amd_i2c_dev_common(i2c_common); + + return i2c_amd_enable_set(i2c_dev, true); +} +#endif + +static const u32 supported_speeds[] = { + I2C_MAX_HIGH_SPEED_MODE_FREQ, + I2C_MAX_TURBO_MODE_FREQ, + I2C_MAX_FAST_MODE_PLUS_FREQ, + I2C_MAX_FAST_MODE_FREQ, + I2C_MAX_STANDARD_MODE_FREQ, +}; + +static enum speed_enum i2c_amd_get_bus_speed(struct platform_device *pdev) +{ + u32 acpi_speed; + int i; + + acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev); + /* round down to the lowest standard speed */ + for (i = 0; i < ARRAY_SIZE(supported_speeds); i++) { + if (acpi_speed >= supported_speeds[i]) + break; + } + acpi_speed = i < ARRAY_SIZE(supported_speeds) ? supported_speeds[i] : 0; + + switch (acpi_speed) { + case I2C_MAX_STANDARD_MODE_FREQ: + return speed100k; + case I2C_MAX_FAST_MODE_FREQ: + return speed400k; + case I2C_MAX_FAST_MODE_PLUS_FREQ: + return speed1000k; + case I2C_MAX_TURBO_MODE_FREQ: + return speed1400k; + case I2C_MAX_HIGH_SPEED_MODE_FREQ: + return speed3400k; + default: + return speed400k; + } +} + +static const struct i2c_adapter_quirks amd_i2c_dev_quirks = { + .max_read_len = AMD_MP2_I2C_MAX_RW_LENGTH, + .max_write_len = AMD_MP2_I2C_MAX_RW_LENGTH, +}; + +static int i2c_amd_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + int ret; + struct amd_i2c_dev *i2c_dev; + struct amd_mp2_dev *mp2_dev; + u64 uid; + + ret = acpi_dev_uid_to_integer(ACPI_COMPANION(dev), &uid); + if (ret) + return dev_err_probe(dev, ret, "missing UID/bus id!\n"); + if (uid >= 2) + return dev_err_probe(dev, -EINVAL, "incorrect UID/bus id \"%llu\"!\n", uid); + dev_dbg(dev, "bus id is %llu\n", uid); + + /* The ACPI namespace doesn't contain information about which MP2 PCI + * device an AMDI0011 ACPI device is related to, so assume that there's + * only one MP2 PCI device per system. + */ + mp2_dev = amd_mp2_find_device(); + if (!mp2_dev || !mp2_dev->probed) + /* The MP2 PCI device should get probed later */ + return -EPROBE_DEFER; + + i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); + if (!i2c_dev) + return -ENOMEM; + + i2c_dev->common.bus_id = uid; + i2c_dev->common.mp2_dev = mp2_dev; + i2c_dev->pdev = pdev; + platform_set_drvdata(pdev, i2c_dev); + + i2c_dev->common.cmd_completion = &i2c_amd_cmd_completion; +#ifdef CONFIG_PM + i2c_dev->common.suspend = &i2c_amd_suspend; + i2c_dev->common.resume = &i2c_amd_resume; +#endif + + /* Register the adapter */ + amd_mp2_pm_runtime_get(mp2_dev); + + i2c_dev->common.reqcmd = i2c_none; + if (amd_mp2_register_cb(&i2c_dev->common)) + return -EINVAL; + device_link_add(&i2c_dev->pdev->dev, &mp2_dev->pci_dev->dev, + DL_FLAG_AUTOREMOVE_CONSUMER); + + i2c_dev->common.i2c_speed = i2c_amd_get_bus_speed(pdev); + + /* Setup i2c adapter description */ + i2c_dev->adap.owner = THIS_MODULE; + i2c_dev->adap.algo = &i2c_amd_algorithm; + i2c_dev->adap.quirks = &amd_i2c_dev_quirks; + i2c_dev->adap.dev.parent = &pdev->dev; + i2c_dev->adap.algo_data = i2c_dev; + i2c_dev->adap.timeout = AMD_I2C_TIMEOUT; + ACPI_COMPANION_SET(&i2c_dev->adap.dev, ACPI_COMPANION(&pdev->dev)); + i2c_dev->adap.dev.of_node = pdev->dev.of_node; + snprintf(i2c_dev->adap.name, sizeof(i2c_dev->adap.name), + "AMD MP2 i2c bus %u", i2c_dev->common.bus_id); + i2c_set_adapdata(&i2c_dev->adap, i2c_dev); + + init_completion(&i2c_dev->cmd_complete); + + /* Enable the bus */ + if (i2c_amd_enable_set(i2c_dev, true)) + dev_err(&pdev->dev, "initial bus enable failed\n"); + + /* Attach to the i2c layer */ + ret = i2c_add_adapter(&i2c_dev->adap); + + amd_mp2_pm_runtime_put(mp2_dev); + + if (ret < 0) + dev_err(&pdev->dev, "i2c add adapter failed = %d\n", ret); + + return ret; +} + +static void i2c_amd_remove(struct platform_device *pdev) +{ + struct amd_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + struct amd_i2c_common *i2c_common = &i2c_dev->common; + + i2c_lock_bus(&i2c_dev->adap, I2C_LOCK_ROOT_ADAPTER); + + i2c_amd_enable_set(i2c_dev, false); + amd_mp2_unregister_cb(i2c_common); + i2c_common->mp2_dev = NULL; + + i2c_unlock_bus(&i2c_dev->adap, I2C_LOCK_ROOT_ADAPTER); + + i2c_del_adapter(&i2c_dev->adap); +} + +static const struct acpi_device_id i2c_amd_acpi_match[] = { + { "AMDI0011" }, + { }, +}; +MODULE_DEVICE_TABLE(acpi, i2c_amd_acpi_match); + +static struct platform_driver i2c_amd_plat_driver = { + .probe = i2c_amd_probe, + .remove_new = i2c_amd_remove, + .driver = { + .name = "i2c_amd_mp2", + .acpi_match_table = ACPI_PTR(i2c_amd_acpi_match), + }, +}; +module_platform_driver(i2c_amd_plat_driver); + +MODULE_DESCRIPTION("AMD(R) MP2 I2C Platform Driver"); +MODULE_AUTHOR("Nehal Shah <nehal-bakulchandra.shah@amd.com>"); +MODULE_AUTHOR("Elie Morisse <syniurge@gmail.com>"); +MODULE_LICENSE("Dual BSD/GPL"); diff --git a/drivers/i2c/busses/i2c-amd-mp2.h b/drivers/i2c/busses/i2c-amd-mp2.h new file mode 100644 index 000000000..018a42de8 --- /dev/null +++ b/drivers/i2c/busses/i2c-amd-mp2.h @@ -0,0 +1,214 @@ +/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */ +/* + * AMD MP2 I2C adapter driver + * + * Authors: Shyam Sundar S K <Shyam-sundar.S-k@amd.com> + * Elie Morisse <syniurge@gmail.com> + */ + +#ifndef I2C_AMD_PCI_MP2_H +#define I2C_AMD_PCI_MP2_H + +#include <linux/i2c.h> +#include <linux/pci.h> +#include <linux/pm_runtime.h> + +#define PCI_DEVICE_ID_AMD_MP2 0x15E6 + +struct amd_i2c_common; +struct amd_mp2_dev; + +enum { + /* MP2 C2P Message Registers */ + AMD_C2P_MSG0 = 0x10500, /* MP2 Message for I2C0 */ + AMD_C2P_MSG1 = 0x10504, /* MP2 Message for I2C1 */ + AMD_C2P_MSG2 = 0x10508, /* DRAM Address Lo / Data 0 */ + AMD_C2P_MSG3 = 0x1050c, /* DRAM Address HI / Data 1 */ + AMD_C2P_MSG4 = 0x10510, /* Data 2 */ + AMD_C2P_MSG5 = 0x10514, /* Data 3 */ + AMD_C2P_MSG6 = 0x10518, /* Data 4 */ + AMD_C2P_MSG7 = 0x1051c, /* Data 5 */ + AMD_C2P_MSG8 = 0x10520, /* Data 6 */ + AMD_C2P_MSG9 = 0x10524, /* Data 7 */ + + /* MP2 P2C Message Registers */ + AMD_P2C_MSG0 = 0x10680, /* Do not use */ + AMD_P2C_MSG1 = 0x10684, /* I2C0 interrupt register */ + AMD_P2C_MSG2 = 0x10688, /* I2C1 interrupt register */ + AMD_P2C_MSG3 = 0x1068C, /* MP2 debug info */ + AMD_P2C_MSG_INTEN = 0x10690, /* MP2 interrupt gen register */ + AMD_P2C_MSG_INTSTS = 0x10694, /* Interrupt status */ +}; + +/* Command register data structures */ + +#define i2c_none (-1) +enum i2c_cmd { + i2c_read = 0, + i2c_write, + i2c_enable, + i2c_disable, + number_of_sensor_discovered, + is_mp2_active, + invalid_cmd = 0xF, +}; + +enum speed_enum { + speed100k = 0, + speed400k = 1, + speed1000k = 2, + speed1400k = 3, + speed3400k = 4 +}; + +enum mem_type { + use_dram = 0, + use_c2pmsg = 1, +}; + +/** + * union i2c_cmd_base : bit access of C2P commands + * @i2c_cmd: bit 0..3 i2c R/W command + * @bus_id: bit 4..7 i2c bus index + * @slave_addr: bit 8..15 slave address + * @length: bit 16..27 read/write length + * @i2c_speed: bit 28..30 bus speed + * @mem_type: bit 31 0-DRAM; 1-C2P msg o/p + */ +union i2c_cmd_base { + u32 ul; + struct { + enum i2c_cmd i2c_cmd : 4; + u8 bus_id : 4; + u32 slave_addr : 8; + u32 length : 12; + enum speed_enum i2c_speed : 3; + enum mem_type mem_type : 1; + } s; +}; + +enum response_type { + invalid_response = 0, + command_success = 1, + command_failed = 2, +}; + +enum status_type { + i2c_readcomplete_event = 0, + i2c_readfail_event = 1, + i2c_writecomplete_event = 2, + i2c_writefail_event = 3, + i2c_busenable_complete = 4, + i2c_busenable_failed = 5, + i2c_busdisable_complete = 6, + i2c_busdisable_failed = 7, + invalid_data_length = 8, + invalid_slave_address = 9, + invalid_i2cbus_id = 10, + invalid_dram_addr = 11, + invalid_command = 12, + mp2_active = 13, + numberof_sensors_discovered_resp = 14, + i2c_bus_notinitialized +}; + +/** + * union i2c_event : bit access of P2C events + * @response: bit 0..1 i2c response type + * @status: bit 2..6 status_type + * @mem_type: bit 7 0-DRAM; 1-C2P msg o/p + * @bus_id: bit 8..11 i2c bus id + * @length: bit 12..23 message length + * @slave_addr: bit 24-31 slave address + */ +union i2c_event { + u32 ul; + struct { + enum response_type response : 2; + enum status_type status : 5; + enum mem_type mem_type : 1; + u8 bus_id : 4; + u32 length : 12; + u32 slave_addr : 8; + } r; +}; + +/** + * struct amd_i2c_common - per bus/i2c adapter context, shared + * between the pci and the platform driver + * @eventval: MP2 event value set by the IRQ handler + * @mp2_dev: MP2 pci device this adapter is part of + * @msg: i2c message + * @cmd_completion: function called by the IRQ handler to signal + * the platform driver + * @reqcmd: requested i2c command type + * @cmd_success: set to true if the MP2 responded to a command with + * the expected status and response type + * @bus_id: bus index + * @i2c_speed: i2c bus speed determined by the slowest slave + * @dma_buf: if msg length > 32, holds the DMA buffer virtual address + * @dma_addr: if msg length > 32, holds the DMA buffer address + */ +struct amd_i2c_common { + union i2c_event eventval; + struct amd_mp2_dev *mp2_dev; + struct i2c_msg *msg; + void (*cmd_completion)(struct amd_i2c_common *i2c_common); + enum i2c_cmd reqcmd; + u8 cmd_success; + u8 bus_id; + enum speed_enum i2c_speed; + u8 *dma_buf; + dma_addr_t dma_addr; +#ifdef CONFIG_PM + int (*suspend)(struct amd_i2c_common *i2c_common); + int (*resume)(struct amd_i2c_common *i2c_common); +#endif /* CONFIG_PM */ +}; + +/** + * struct amd_mp2_dev - per PCI device context + * @pci_dev: PCI driver node + * @busses: MP2 devices may have up to two busses, + * each bus corresponding to an i2c adapter + * @mmio: iommapped registers + * @c2p_lock: controls access to the C2P mailbox shared between + * the two adapters + * @c2p_lock_busid: id of the adapter which locked c2p_lock + */ +struct amd_mp2_dev { + struct pci_dev *pci_dev; + struct amd_i2c_common *busses[2]; + void __iomem *mmio; + struct mutex c2p_lock; + u8 c2p_lock_busid; + unsigned int probed; + int dev_irq; +}; + +/* PCIe communication driver */ + +int amd_mp2_rw(struct amd_i2c_common *i2c_common, enum i2c_cmd reqcmd); +int amd_mp2_bus_enable_set(struct amd_i2c_common *i2c_common, bool enable); + +void amd_mp2_process_event(struct amd_i2c_common *i2c_common); + +void amd_mp2_rw_timeout(struct amd_i2c_common *i2c_common); + +int amd_mp2_register_cb(struct amd_i2c_common *i2c_common); +int amd_mp2_unregister_cb(struct amd_i2c_common *i2c_common); + +struct amd_mp2_dev *amd_mp2_find_device(void); + +static inline void amd_mp2_pm_runtime_get(struct amd_mp2_dev *mp2_dev) +{ + pm_runtime_get_sync(&mp2_dev->pci_dev->dev); +} + +static inline void amd_mp2_pm_runtime_put(struct amd_mp2_dev *mp2_dev) +{ + pm_runtime_mark_last_busy(&mp2_dev->pci_dev->dev); + pm_runtime_put_autosuspend(&mp2_dev->pci_dev->dev); +} + +#endif diff --git a/drivers/i2c/busses/i2c-amd756-s4882.c b/drivers/i2c/busses/i2c-amd756-s4882.c new file mode 100644 index 000000000..063274388 --- /dev/null +++ b/drivers/i2c/busses/i2c-amd756-s4882.c @@ -0,0 +1,245 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * i2c-amd756-s4882.c - i2c-amd756 extras for the Tyan S4882 motherboard + * + * Copyright (C) 2004, 2008 Jean Delvare <jdelvare@suse.de> + */ + +/* + * We select the channels by sending commands to the Philips + * PCA9556 chip at I2C address 0x18. The main adapter is used for + * the non-multiplexed part of the bus, and 4 virtual adapters + * are defined for the multiplexed addresses: 0x50-0x53 (memory + * module EEPROM) located on channels 1-4, and 0x4c (LM63) + * located on multiplexed channels 0 and 5-7. We define one + * virtual adapter per CPU, which corresponds to two multiplexed + * channels: + * CPU0: virtual adapter 1, channels 1 and 0 + * CPU1: virtual adapter 2, channels 2 and 5 + * CPU2: virtual adapter 3, channels 3 and 6 + * CPU3: virtual adapter 4, channels 4 and 7 + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/mutex.h> + +extern struct i2c_adapter amd756_smbus; + +static struct i2c_adapter *s4882_adapter; +static struct i2c_algorithm *s4882_algo; + +/* Wrapper access functions for multiplexed SMBus */ +static DEFINE_MUTEX(amd756_lock); + +static s32 amd756_access_virt0(struct i2c_adapter * adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data * data) +{ + int error; + + /* We exclude the multiplexed addresses */ + if (addr == 0x4c || (addr & 0xfc) == 0x50 || (addr & 0xfc) == 0x30 + || addr == 0x18) + return -ENXIO; + + mutex_lock(&amd756_lock); + + error = amd756_smbus.algo->smbus_xfer(adap, addr, flags, read_write, + command, size, data); + + mutex_unlock(&amd756_lock); + + return error; +} + +/* We remember the last used channels combination so as to only switch + channels when it is really needed. This greatly reduces the SMBus + overhead, but also assumes that nobody will be writing to the PCA9556 + in our back. */ +static u8 last_channels; + +static inline s32 amd756_access_channel(struct i2c_adapter * adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data * data, + u8 channels) +{ + int error; + + /* We exclude the non-multiplexed addresses */ + if (addr != 0x4c && (addr & 0xfc) != 0x50 && (addr & 0xfc) != 0x30) + return -ENXIO; + + mutex_lock(&amd756_lock); + + if (last_channels != channels) { + union i2c_smbus_data mplxdata; + mplxdata.byte = channels; + + error = amd756_smbus.algo->smbus_xfer(adap, 0x18, 0, + I2C_SMBUS_WRITE, 0x01, + I2C_SMBUS_BYTE_DATA, + &mplxdata); + if (error) + goto UNLOCK; + last_channels = channels; + } + error = amd756_smbus.algo->smbus_xfer(adap, addr, flags, read_write, + command, size, data); + +UNLOCK: + mutex_unlock(&amd756_lock); + return error; +} + +static s32 amd756_access_virt1(struct i2c_adapter * adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data * data) +{ + /* CPU0: channels 1 and 0 enabled */ + return amd756_access_channel(adap, addr, flags, read_write, command, + size, data, 0x03); +} + +static s32 amd756_access_virt2(struct i2c_adapter * adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data * data) +{ + /* CPU1: channels 2 and 5 enabled */ + return amd756_access_channel(adap, addr, flags, read_write, command, + size, data, 0x24); +} + +static s32 amd756_access_virt3(struct i2c_adapter * adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data * data) +{ + /* CPU2: channels 3 and 6 enabled */ + return amd756_access_channel(adap, addr, flags, read_write, command, + size, data, 0x48); +} + +static s32 amd756_access_virt4(struct i2c_adapter * adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data * data) +{ + /* CPU3: channels 4 and 7 enabled */ + return amd756_access_channel(adap, addr, flags, read_write, command, + size, data, 0x90); +} + +static int __init amd756_s4882_init(void) +{ + int i, error; + union i2c_smbus_data ioconfig; + + if (!amd756_smbus.dev.parent) + return -ENODEV; + + /* Configure the PCA9556 multiplexer */ + ioconfig.byte = 0x00; /* All I/O to output mode */ + error = i2c_smbus_xfer(&amd756_smbus, 0x18, 0, I2C_SMBUS_WRITE, 0x03, + I2C_SMBUS_BYTE_DATA, &ioconfig); + if (error) { + dev_err(&amd756_smbus.dev, "PCA9556 configuration failed\n"); + error = -EIO; + goto ERROR0; + } + + /* Unregister physical bus */ + i2c_del_adapter(&amd756_smbus); + + printk(KERN_INFO "Enabling SMBus multiplexing for Tyan S4882\n"); + /* Define the 5 virtual adapters and algorithms structures */ + if (!(s4882_adapter = kcalloc(5, sizeof(struct i2c_adapter), + GFP_KERNEL))) { + error = -ENOMEM; + goto ERROR1; + } + if (!(s4882_algo = kcalloc(5, sizeof(struct i2c_algorithm), + GFP_KERNEL))) { + error = -ENOMEM; + goto ERROR2; + } + + /* Fill in the new structures */ + s4882_algo[0] = *(amd756_smbus.algo); + s4882_algo[0].smbus_xfer = amd756_access_virt0; + s4882_adapter[0] = amd756_smbus; + s4882_adapter[0].algo = s4882_algo; + s4882_adapter[0].dev.parent = amd756_smbus.dev.parent; + for (i = 1; i < 5; i++) { + s4882_algo[i] = *(amd756_smbus.algo); + s4882_adapter[i] = amd756_smbus; + snprintf(s4882_adapter[i].name, sizeof(s4882_adapter[i].name), + "SMBus 8111 adapter (CPU%d)", i-1); + s4882_adapter[i].algo = s4882_algo+i; + s4882_adapter[i].dev.parent = amd756_smbus.dev.parent; + } + s4882_algo[1].smbus_xfer = amd756_access_virt1; + s4882_algo[2].smbus_xfer = amd756_access_virt2; + s4882_algo[3].smbus_xfer = amd756_access_virt3; + s4882_algo[4].smbus_xfer = amd756_access_virt4; + + /* Register virtual adapters */ + for (i = 0; i < 5; i++) { + error = i2c_add_adapter(s4882_adapter+i); + if (error) { + printk(KERN_ERR "i2c-amd756-s4882: " + "Virtual adapter %d registration " + "failed, module not inserted\n", i); + for (i--; i >= 0; i--) + i2c_del_adapter(s4882_adapter+i); + goto ERROR3; + } + } + + return 0; + +ERROR3: + kfree(s4882_algo); + s4882_algo = NULL; +ERROR2: + kfree(s4882_adapter); + s4882_adapter = NULL; +ERROR1: + /* Restore physical bus */ + i2c_add_adapter(&amd756_smbus); +ERROR0: + return error; +} + +static void __exit amd756_s4882_exit(void) +{ + if (s4882_adapter) { + int i; + + for (i = 0; i < 5; i++) + i2c_del_adapter(s4882_adapter+i); + kfree(s4882_adapter); + s4882_adapter = NULL; + } + kfree(s4882_algo); + s4882_algo = NULL; + + /* Restore physical bus */ + if (i2c_add_adapter(&amd756_smbus)) + printk(KERN_ERR "i2c-amd756-s4882: " + "Physical bus restoration failed\n"); +} + +MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>"); +MODULE_DESCRIPTION("S4882 SMBus multiplexing"); +MODULE_LICENSE("GPL"); + +module_init(amd756_s4882_init); +module_exit(amd756_s4882_exit); diff --git a/drivers/i2c/busses/i2c-amd756.c b/drivers/i2c/busses/i2c-amd756.c new file mode 100644 index 000000000..ef1307a25 --- /dev/null +++ b/drivers/i2c/busses/i2c-amd756.c @@ -0,0 +1,402 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + Copyright (c) 1999-2002 Merlin Hughes <merlin@merlin.org> + + Shamelessly ripped from i2c-piix4.c: + + Copyright (c) 1998, 1999 Frodo Looijaard <frodol@dds.nl> and + Philip Edelbrock <phil@netroedge.com> + +*/ + +/* + 2002-04-08: Added nForce support. (Csaba Halasz) + 2002-10-03: Fixed nForce PnP I/O port. (Michael Steil) + 2002-12-28: Rewritten into something that resembles a Linux driver (hch) + 2003-11-29: Added back AMD8111 removed by the previous rewrite. + (Philip Pokorny) +*/ + +/* + Supports AMD756, AMD766, AMD768, AMD8111 and nVidia nForce + Note: we assume there can only be one device, with one SMBus interface. +*/ + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/stddef.h> +#include <linux/ioport.h> +#include <linux/i2c.h> +#include <linux/acpi.h> +#include <linux/io.h> + +/* AMD756 SMBus address offsets */ +#define SMB_ADDR_OFFSET 0xE0 +#define SMB_IOSIZE 16 +#define SMB_GLOBAL_STATUS (0x0 + amd756_ioport) +#define SMB_GLOBAL_ENABLE (0x2 + amd756_ioport) +#define SMB_HOST_ADDRESS (0x4 + amd756_ioport) +#define SMB_HOST_DATA (0x6 + amd756_ioport) +#define SMB_HOST_COMMAND (0x8 + amd756_ioport) +#define SMB_HOST_BLOCK_DATA (0x9 + amd756_ioport) +#define SMB_HAS_DATA (0xA + amd756_ioport) +#define SMB_HAS_DEVICE_ADDRESS (0xC + amd756_ioport) +#define SMB_HAS_HOST_ADDRESS (0xE + amd756_ioport) +#define SMB_SNOOP_ADDRESS (0xF + amd756_ioport) + +/* PCI Address Constants */ + +/* address of I/O space */ +#define SMBBA 0x058 /* mh */ +#define SMBBANFORCE 0x014 + +/* general configuration */ +#define SMBGCFG 0x041 /* mh */ + +/* silicon revision code */ +#define SMBREV 0x008 + +/* Other settings */ +#define MAX_TIMEOUT 500 + +/* AMD756 constants */ +#define AMD756_QUICK 0x00 +#define AMD756_BYTE 0x01 +#define AMD756_BYTE_DATA 0x02 +#define AMD756_WORD_DATA 0x03 +#define AMD756_PROCESS_CALL 0x04 +#define AMD756_BLOCK_DATA 0x05 + +static struct pci_driver amd756_driver; +static unsigned short amd756_ioport; + +/* + SMBUS event = I/O 28-29 bit 11 + see E0 for the status bits and enabled in E2 + +*/ +#define GS_ABRT_STS (1 << 0) +#define GS_COL_STS (1 << 1) +#define GS_PRERR_STS (1 << 2) +#define GS_HST_STS (1 << 3) +#define GS_HCYC_STS (1 << 4) +#define GS_TO_STS (1 << 5) +#define GS_SMB_STS (1 << 11) + +#define GS_CLEAR_STS (GS_ABRT_STS | GS_COL_STS | GS_PRERR_STS | \ + GS_HCYC_STS | GS_TO_STS ) + +#define GE_CYC_TYPE_MASK (7) +#define GE_HOST_STC (1 << 3) +#define GE_ABORT (1 << 5) + + +static int amd756_transaction(struct i2c_adapter *adap) +{ + int temp; + int result = 0; + int timeout = 0; + + dev_dbg(&adap->dev, "Transaction (pre): GS=%04x, GE=%04x, ADD=%04x, " + "DAT=%04x\n", inw_p(SMB_GLOBAL_STATUS), + inw_p(SMB_GLOBAL_ENABLE), inw_p(SMB_HOST_ADDRESS), + inb_p(SMB_HOST_DATA)); + + /* Make sure the SMBus host is ready to start transmitting */ + if ((temp = inw_p(SMB_GLOBAL_STATUS)) & (GS_HST_STS | GS_SMB_STS)) { + dev_dbg(&adap->dev, "SMBus busy (%04x). Waiting...\n", temp); + do { + msleep(1); + temp = inw_p(SMB_GLOBAL_STATUS); + } while ((temp & (GS_HST_STS | GS_SMB_STS)) && + (timeout++ < MAX_TIMEOUT)); + /* If the SMBus is still busy, we give up */ + if (timeout > MAX_TIMEOUT) { + dev_dbg(&adap->dev, "Busy wait timeout (%04x)\n", temp); + goto abort; + } + timeout = 0; + } + + /* start the transaction by setting the start bit */ + outw_p(inw(SMB_GLOBAL_ENABLE) | GE_HOST_STC, SMB_GLOBAL_ENABLE); + + /* We will always wait for a fraction of a second! */ + do { + msleep(1); + temp = inw_p(SMB_GLOBAL_STATUS); + } while ((temp & GS_HST_STS) && (timeout++ < MAX_TIMEOUT)); + + /* If the SMBus is still busy, we give up */ + if (timeout > MAX_TIMEOUT) { + dev_dbg(&adap->dev, "Completion timeout!\n"); + goto abort; + } + + if (temp & GS_PRERR_STS) { + result = -ENXIO; + dev_dbg(&adap->dev, "SMBus Protocol error (no response)!\n"); + } + + if (temp & GS_COL_STS) { + result = -EIO; + dev_warn(&adap->dev, "SMBus collision!\n"); + } + + if (temp & GS_TO_STS) { + result = -ETIMEDOUT; + dev_dbg(&adap->dev, "SMBus protocol timeout!\n"); + } + + if (temp & GS_HCYC_STS) + dev_dbg(&adap->dev, "SMBus protocol success!\n"); + + outw_p(GS_CLEAR_STS, SMB_GLOBAL_STATUS); + +#ifdef DEBUG + if (((temp = inw_p(SMB_GLOBAL_STATUS)) & GS_CLEAR_STS) != 0x00) { + dev_dbg(&adap->dev, + "Failed reset at end of transaction (%04x)\n", temp); + } +#endif + + dev_dbg(&adap->dev, + "Transaction (post): GS=%04x, GE=%04x, ADD=%04x, DAT=%04x\n", + inw_p(SMB_GLOBAL_STATUS), inw_p(SMB_GLOBAL_ENABLE), + inw_p(SMB_HOST_ADDRESS), inb_p(SMB_HOST_DATA)); + + return result; + + abort: + dev_warn(&adap->dev, "Sending abort\n"); + outw_p(inw(SMB_GLOBAL_ENABLE) | GE_ABORT, SMB_GLOBAL_ENABLE); + msleep(100); + outw_p(GS_CLEAR_STS, SMB_GLOBAL_STATUS); + return -EIO; +} + +/* Return negative errno on error. */ +static s32 amd756_access(struct i2c_adapter * adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data * data) +{ + int i, len; + int status; + + switch (size) { + case I2C_SMBUS_QUICK: + outw_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMB_HOST_ADDRESS); + size = AMD756_QUICK; + break; + case I2C_SMBUS_BYTE: + outw_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMB_HOST_ADDRESS); + if (read_write == I2C_SMBUS_WRITE) + outb_p(command, SMB_HOST_DATA); + size = AMD756_BYTE; + break; + case I2C_SMBUS_BYTE_DATA: + outw_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMB_HOST_ADDRESS); + outb_p(command, SMB_HOST_COMMAND); + if (read_write == I2C_SMBUS_WRITE) + outw_p(data->byte, SMB_HOST_DATA); + size = AMD756_BYTE_DATA; + break; + case I2C_SMBUS_WORD_DATA: + outw_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMB_HOST_ADDRESS); + outb_p(command, SMB_HOST_COMMAND); + if (read_write == I2C_SMBUS_WRITE) + outw_p(data->word, SMB_HOST_DATA); /* TODO: endian???? */ + size = AMD756_WORD_DATA; + break; + case I2C_SMBUS_BLOCK_DATA: + outw_p(((addr & 0x7f) << 1) | (read_write & 0x01), + SMB_HOST_ADDRESS); + outb_p(command, SMB_HOST_COMMAND); + if (read_write == I2C_SMBUS_WRITE) { + len = data->block[0]; + if (len < 0) + len = 0; + if (len > 32) + len = 32; + outw_p(len, SMB_HOST_DATA); + /* i = inw_p(SMBHSTCNT); Reset SMBBLKDAT */ + for (i = 1; i <= len; i++) + outb_p(data->block[i], + SMB_HOST_BLOCK_DATA); + } + size = AMD756_BLOCK_DATA; + break; + default: + dev_warn(&adap->dev, "Unsupported transaction %d\n", size); + return -EOPNOTSUPP; + } + + /* How about enabling interrupts... */ + outw_p(size & GE_CYC_TYPE_MASK, SMB_GLOBAL_ENABLE); + + status = amd756_transaction(adap); + if (status) + return status; + + if ((read_write == I2C_SMBUS_WRITE) || (size == AMD756_QUICK)) + return 0; + + + switch (size) { + case AMD756_BYTE: + data->byte = inw_p(SMB_HOST_DATA); + break; + case AMD756_BYTE_DATA: + data->byte = inw_p(SMB_HOST_DATA); + break; + case AMD756_WORD_DATA: + data->word = inw_p(SMB_HOST_DATA); /* TODO: endian???? */ + break; + case AMD756_BLOCK_DATA: + data->block[0] = inw_p(SMB_HOST_DATA) & 0x3f; + if(data->block[0] > 32) + data->block[0] = 32; + /* i = inw_p(SMBHSTCNT); Reset SMBBLKDAT */ + for (i = 1; i <= data->block[0]; i++) + data->block[i] = inb_p(SMB_HOST_BLOCK_DATA); + break; + } + + return 0; +} + +static u32 amd756_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_BLOCK_DATA; +} + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = amd756_access, + .functionality = amd756_func, +}; + +struct i2c_adapter amd756_smbus = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = &smbus_algorithm, +}; + +enum chiptype { AMD756, AMD766, AMD768, NFORCE, AMD8111 }; +static const char* chipname[] = { + "AMD756", "AMD766", "AMD768", + "nVidia nForce", "AMD8111", +}; + +static const struct pci_device_id amd756_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_VIPER_740B), + .driver_data = AMD756 }, + { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_VIPER_7413), + .driver_data = AMD766 }, + { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_OPUS_7443), + .driver_data = AMD768 }, + { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8111_SMBUS), + .driver_data = AMD8111 }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_SMBUS), + .driver_data = NFORCE }, + { 0, } +}; + +MODULE_DEVICE_TABLE (pci, amd756_ids); + +static int amd756_probe(struct pci_dev *pdev, const struct pci_device_id *id) +{ + int nforce = (id->driver_data == NFORCE); + int error; + u8 temp; + + if (amd756_ioport) { + dev_err(&pdev->dev, "Only one device supported " + "(you have a strange motherboard, btw)\n"); + return -ENODEV; + } + + if (nforce) { + if (PCI_FUNC(pdev->devfn) != 1) + return -ENODEV; + + pci_read_config_word(pdev, SMBBANFORCE, &amd756_ioport); + amd756_ioport &= 0xfffc; + } else { /* amd */ + if (PCI_FUNC(pdev->devfn) != 3) + return -ENODEV; + + pci_read_config_byte(pdev, SMBGCFG, &temp); + if ((temp & 128) == 0) { + dev_err(&pdev->dev, + "Error: SMBus controller I/O not enabled!\n"); + return -ENODEV; + } + + /* Determine the address of the SMBus areas */ + /* Technically it is a dword but... */ + pci_read_config_word(pdev, SMBBA, &amd756_ioport); + amd756_ioport &= 0xff00; + amd756_ioport += SMB_ADDR_OFFSET; + } + + error = acpi_check_region(amd756_ioport, SMB_IOSIZE, + amd756_driver.name); + if (error) + return -ENODEV; + + if (!request_region(amd756_ioport, SMB_IOSIZE, amd756_driver.name)) { + dev_err(&pdev->dev, "SMB region 0x%x already in use!\n", + amd756_ioport); + return -ENODEV; + } + + pci_read_config_byte(pdev, SMBREV, &temp); + dev_dbg(&pdev->dev, "SMBREV = 0x%X\n", temp); + dev_dbg(&pdev->dev, "AMD756_smba = 0x%X\n", amd756_ioport); + + /* set up the sysfs linkage to our parent device */ + amd756_smbus.dev.parent = &pdev->dev; + + snprintf(amd756_smbus.name, sizeof(amd756_smbus.name), + "SMBus %s adapter at %04x", chipname[id->driver_data], + amd756_ioport); + + error = i2c_add_adapter(&amd756_smbus); + if (error) + goto out_err; + + return 0; + + out_err: + release_region(amd756_ioport, SMB_IOSIZE); + return error; +} + +static void amd756_remove(struct pci_dev *dev) +{ + i2c_del_adapter(&amd756_smbus); + release_region(amd756_ioport, SMB_IOSIZE); +} + +static struct pci_driver amd756_driver = { + .name = "amd756_smbus", + .id_table = amd756_ids, + .probe = amd756_probe, + .remove = amd756_remove, +}; + +module_pci_driver(amd756_driver); + +MODULE_AUTHOR("Merlin Hughes <merlin@merlin.org>"); +MODULE_DESCRIPTION("AMD756/766/768/8111 and nVidia nForce SMBus driver"); +MODULE_LICENSE("GPL"); + +EXPORT_SYMBOL(amd756_smbus); diff --git a/drivers/i2c/busses/i2c-amd8111.c b/drivers/i2c/busses/i2c-amd8111.c new file mode 100644 index 000000000..1ed7e945b --- /dev/null +++ b/drivers/i2c/busses/i2c-amd8111.c @@ -0,0 +1,490 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * SMBus 2.0 driver for AMD-8111 IO-Hub. + * + * Copyright (c) 2002 Vojtech Pavlik + */ + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/stddef.h> +#include <linux/ioport.h> +#include <linux/i2c.h> +#include <linux/delay.h> +#include <linux/acpi.h> +#include <linux/slab.h> +#include <linux/io.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR ("Vojtech Pavlik <vojtech@suse.cz>"); +MODULE_DESCRIPTION("AMD8111 SMBus 2.0 driver"); + +struct amd_smbus { + struct pci_dev *dev; + struct i2c_adapter adapter; + int base; + int size; +}; + +static struct pci_driver amd8111_driver; + +/* + * AMD PCI control registers definitions. + */ + +#define AMD_PCI_MISC 0x48 + +#define AMD_PCI_MISC_SCI 0x04 /* deliver SCI */ +#define AMD_PCI_MISC_INT 0x02 /* deliver PCI IRQ */ +#define AMD_PCI_MISC_SPEEDUP 0x01 /* 16x clock speedup */ + +/* + * ACPI 2.0 chapter 13 PCI interface definitions. + */ + +#define AMD_EC_DATA 0x00 /* data register */ +#define AMD_EC_SC 0x04 /* status of controller */ +#define AMD_EC_CMD 0x04 /* command register */ +#define AMD_EC_ICR 0x08 /* interrupt control register */ + +#define AMD_EC_SC_SMI 0x04 /* smi event pending */ +#define AMD_EC_SC_SCI 0x02 /* sci event pending */ +#define AMD_EC_SC_BURST 0x01 /* burst mode enabled */ +#define AMD_EC_SC_CMD 0x08 /* byte in data reg is command */ +#define AMD_EC_SC_IBF 0x02 /* data ready for embedded controller */ +#define AMD_EC_SC_OBF 0x01 /* data ready for host */ + +#define AMD_EC_CMD_RD 0x80 /* read EC */ +#define AMD_EC_CMD_WR 0x81 /* write EC */ +#define AMD_EC_CMD_BE 0x82 /* enable burst mode */ +#define AMD_EC_CMD_BD 0x83 /* disable burst mode */ +#define AMD_EC_CMD_QR 0x84 /* query EC */ + +/* + * ACPI 2.0 chapter 13 access of registers of the EC + */ + +static int amd_ec_wait_write(struct amd_smbus *smbus) +{ + int timeout = 500; + + while ((inb(smbus->base + AMD_EC_SC) & AMD_EC_SC_IBF) && --timeout) + udelay(1); + + if (!timeout) { + dev_warn(&smbus->dev->dev, + "Timeout while waiting for IBF to clear\n"); + return -ETIMEDOUT; + } + + return 0; +} + +static int amd_ec_wait_read(struct amd_smbus *smbus) +{ + int timeout = 500; + + while ((~inb(smbus->base + AMD_EC_SC) & AMD_EC_SC_OBF) && --timeout) + udelay(1); + + if (!timeout) { + dev_warn(&smbus->dev->dev, + "Timeout while waiting for OBF to set\n"); + return -ETIMEDOUT; + } + + return 0; +} + +static int amd_ec_read(struct amd_smbus *smbus, unsigned char address, + unsigned char *data) +{ + int status; + + status = amd_ec_wait_write(smbus); + if (status) + return status; + outb(AMD_EC_CMD_RD, smbus->base + AMD_EC_CMD); + + status = amd_ec_wait_write(smbus); + if (status) + return status; + outb(address, smbus->base + AMD_EC_DATA); + + status = amd_ec_wait_read(smbus); + if (status) + return status; + *data = inb(smbus->base + AMD_EC_DATA); + + return 0; +} + +static int amd_ec_write(struct amd_smbus *smbus, unsigned char address, + unsigned char data) +{ + int status; + + status = amd_ec_wait_write(smbus); + if (status) + return status; + outb(AMD_EC_CMD_WR, smbus->base + AMD_EC_CMD); + + status = amd_ec_wait_write(smbus); + if (status) + return status; + outb(address, smbus->base + AMD_EC_DATA); + + status = amd_ec_wait_write(smbus); + if (status) + return status; + outb(data, smbus->base + AMD_EC_DATA); + + return 0; +} + +/* + * ACPI 2.0 chapter 13 SMBus 2.0 EC register model + */ + +#define AMD_SMB_PRTCL 0x00 /* protocol, PEC */ +#define AMD_SMB_STS 0x01 /* status */ +#define AMD_SMB_ADDR 0x02 /* address */ +#define AMD_SMB_CMD 0x03 /* command */ +#define AMD_SMB_DATA 0x04 /* 32 data registers */ +#define AMD_SMB_BCNT 0x24 /* number of data bytes */ +#define AMD_SMB_ALRM_A 0x25 /* alarm address */ +#define AMD_SMB_ALRM_D 0x26 /* 2 bytes alarm data */ + +#define AMD_SMB_STS_DONE 0x80 +#define AMD_SMB_STS_ALRM 0x40 +#define AMD_SMB_STS_RES 0x20 +#define AMD_SMB_STS_STATUS 0x1f + +#define AMD_SMB_STATUS_OK 0x00 +#define AMD_SMB_STATUS_FAIL 0x07 +#define AMD_SMB_STATUS_DNAK 0x10 +#define AMD_SMB_STATUS_DERR 0x11 +#define AMD_SMB_STATUS_CMD_DENY 0x12 +#define AMD_SMB_STATUS_UNKNOWN 0x13 +#define AMD_SMB_STATUS_ACC_DENY 0x17 +#define AMD_SMB_STATUS_TIMEOUT 0x18 +#define AMD_SMB_STATUS_NOTSUP 0x19 +#define AMD_SMB_STATUS_BUSY 0x1A +#define AMD_SMB_STATUS_PEC 0x1F + +#define AMD_SMB_PRTCL_WRITE 0x00 +#define AMD_SMB_PRTCL_READ 0x01 +#define AMD_SMB_PRTCL_QUICK 0x02 +#define AMD_SMB_PRTCL_BYTE 0x04 +#define AMD_SMB_PRTCL_BYTE_DATA 0x06 +#define AMD_SMB_PRTCL_WORD_DATA 0x08 +#define AMD_SMB_PRTCL_BLOCK_DATA 0x0a +#define AMD_SMB_PRTCL_PROC_CALL 0x0c +#define AMD_SMB_PRTCL_BLOCK_PROC_CALL 0x0d +#define AMD_SMB_PRTCL_I2C_BLOCK_DATA 0x4a +#define AMD_SMB_PRTCL_PEC 0x80 + + +static s32 amd8111_access(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, u8 command, int size, + union i2c_smbus_data *data) +{ + struct amd_smbus *smbus = adap->algo_data; + unsigned char protocol, len, pec, temp[2]; + int i, status; + + protocol = (read_write == I2C_SMBUS_READ) ? AMD_SMB_PRTCL_READ + : AMD_SMB_PRTCL_WRITE; + pec = (flags & I2C_CLIENT_PEC) ? AMD_SMB_PRTCL_PEC : 0; + + switch (size) { + case I2C_SMBUS_QUICK: + protocol |= AMD_SMB_PRTCL_QUICK; + read_write = I2C_SMBUS_WRITE; + break; + + case I2C_SMBUS_BYTE: + if (read_write == I2C_SMBUS_WRITE) { + status = amd_ec_write(smbus, AMD_SMB_CMD, + command); + if (status) + return status; + } + protocol |= AMD_SMB_PRTCL_BYTE; + break; + + case I2C_SMBUS_BYTE_DATA: + status = amd_ec_write(smbus, AMD_SMB_CMD, command); + if (status) + return status; + if (read_write == I2C_SMBUS_WRITE) { + status = amd_ec_write(smbus, AMD_SMB_DATA, + data->byte); + if (status) + return status; + } + protocol |= AMD_SMB_PRTCL_BYTE_DATA; + break; + + case I2C_SMBUS_WORD_DATA: + status = amd_ec_write(smbus, AMD_SMB_CMD, command); + if (status) + return status; + if (read_write == I2C_SMBUS_WRITE) { + status = amd_ec_write(smbus, AMD_SMB_DATA, + data->word & 0xff); + if (status) + return status; + status = amd_ec_write(smbus, AMD_SMB_DATA + 1, + data->word >> 8); + if (status) + return status; + } + protocol |= AMD_SMB_PRTCL_WORD_DATA | pec; + break; + + case I2C_SMBUS_BLOCK_DATA: + status = amd_ec_write(smbus, AMD_SMB_CMD, command); + if (status) + return status; + if (read_write == I2C_SMBUS_WRITE) { + len = min_t(u8, data->block[0], + I2C_SMBUS_BLOCK_MAX); + status = amd_ec_write(smbus, AMD_SMB_BCNT, len); + if (status) + return status; + for (i = 0; i < len; i++) { + status = + amd_ec_write(smbus, AMD_SMB_DATA + i, + data->block[i + 1]); + if (status) + return status; + } + } + protocol |= AMD_SMB_PRTCL_BLOCK_DATA | pec; + break; + + case I2C_SMBUS_I2C_BLOCK_DATA: + len = min_t(u8, data->block[0], + I2C_SMBUS_BLOCK_MAX); + status = amd_ec_write(smbus, AMD_SMB_CMD, command); + if (status) + return status; + status = amd_ec_write(smbus, AMD_SMB_BCNT, len); + if (status) + return status; + if (read_write == I2C_SMBUS_WRITE) + for (i = 0; i < len; i++) { + status = + amd_ec_write(smbus, AMD_SMB_DATA + i, + data->block[i + 1]); + if (status) + return status; + } + protocol |= AMD_SMB_PRTCL_I2C_BLOCK_DATA; + break; + + case I2C_SMBUS_PROC_CALL: + status = amd_ec_write(smbus, AMD_SMB_CMD, command); + if (status) + return status; + status = amd_ec_write(smbus, AMD_SMB_DATA, + data->word & 0xff); + if (status) + return status; + status = amd_ec_write(smbus, AMD_SMB_DATA + 1, + data->word >> 8); + if (status) + return status; + protocol = AMD_SMB_PRTCL_PROC_CALL | pec; + read_write = I2C_SMBUS_READ; + break; + + case I2C_SMBUS_BLOCK_PROC_CALL: + len = min_t(u8, data->block[0], + I2C_SMBUS_BLOCK_MAX - 1); + status = amd_ec_write(smbus, AMD_SMB_CMD, command); + if (status) + return status; + status = amd_ec_write(smbus, AMD_SMB_BCNT, len); + if (status) + return status; + for (i = 0; i < len; i++) { + status = amd_ec_write(smbus, AMD_SMB_DATA + i, + data->block[i + 1]); + if (status) + return status; + } + protocol = AMD_SMB_PRTCL_BLOCK_PROC_CALL | pec; + read_write = I2C_SMBUS_READ; + break; + + default: + dev_warn(&adap->dev, "Unsupported transaction %d\n", size); + return -EOPNOTSUPP; + } + + status = amd_ec_write(smbus, AMD_SMB_ADDR, addr << 1); + if (status) + return status; + status = amd_ec_write(smbus, AMD_SMB_PRTCL, protocol); + if (status) + return status; + + status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0); + if (status) + return status; + + if (~temp[0] & AMD_SMB_STS_DONE) { + udelay(500); + status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0); + if (status) + return status; + } + + if (~temp[0] & AMD_SMB_STS_DONE) { + msleep(1); + status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0); + if (status) + return status; + } + + if ((~temp[0] & AMD_SMB_STS_DONE) || (temp[0] & AMD_SMB_STS_STATUS)) + return -EIO; + + if (read_write == I2C_SMBUS_WRITE) + return 0; + + switch (size) { + case I2C_SMBUS_BYTE: + case I2C_SMBUS_BYTE_DATA: + status = amd_ec_read(smbus, AMD_SMB_DATA, &data->byte); + if (status) + return status; + break; + + case I2C_SMBUS_WORD_DATA: + case I2C_SMBUS_PROC_CALL: + status = amd_ec_read(smbus, AMD_SMB_DATA, temp + 0); + if (status) + return status; + status = amd_ec_read(smbus, AMD_SMB_DATA + 1, temp + 1); + if (status) + return status; + data->word = (temp[1] << 8) | temp[0]; + break; + + case I2C_SMBUS_BLOCK_DATA: + case I2C_SMBUS_BLOCK_PROC_CALL: + status = amd_ec_read(smbus, AMD_SMB_BCNT, &len); + if (status) + return status; + len = min_t(u8, len, I2C_SMBUS_BLOCK_MAX); + fallthrough; + case I2C_SMBUS_I2C_BLOCK_DATA: + for (i = 0; i < len; i++) { + status = amd_ec_read(smbus, AMD_SMB_DATA + i, + data->block + i + 1); + if (status) + return status; + } + data->block[0] = len; + break; + } + + return 0; +} + + +static u32 amd8111_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BLOCK_DATA | + I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_BLOCK_PROC_CALL | + I2C_FUNC_SMBUS_I2C_BLOCK | I2C_FUNC_SMBUS_PEC; +} + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = amd8111_access, + .functionality = amd8111_func, +}; + + +static const struct pci_device_id amd8111_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8111_SMBUS2) }, + { 0, } +}; + +MODULE_DEVICE_TABLE (pci, amd8111_ids); + +static int amd8111_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + struct amd_smbus *smbus; + int error; + + if (!(pci_resource_flags(dev, 0) & IORESOURCE_IO)) + return -ENODEV; + + smbus = kzalloc(sizeof(struct amd_smbus), GFP_KERNEL); + if (!smbus) + return -ENOMEM; + + smbus->dev = dev; + smbus->base = pci_resource_start(dev, 0); + smbus->size = pci_resource_len(dev, 0); + + error = acpi_check_resource_conflict(&dev->resource[0]); + if (error) { + error = -ENODEV; + goto out_kfree; + } + + if (!request_region(smbus->base, smbus->size, amd8111_driver.name)) { + error = -EBUSY; + goto out_kfree; + } + + smbus->adapter.owner = THIS_MODULE; + snprintf(smbus->adapter.name, sizeof(smbus->adapter.name), + "SMBus2 AMD8111 adapter at %04x", smbus->base); + smbus->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + smbus->adapter.algo = &smbus_algorithm; + smbus->adapter.algo_data = smbus; + + /* set up the sysfs linkage to our parent device */ + smbus->adapter.dev.parent = &dev->dev; + + pci_write_config_dword(smbus->dev, AMD_PCI_MISC, 0); + error = i2c_add_adapter(&smbus->adapter); + if (error) + goto out_release_region; + + pci_set_drvdata(dev, smbus); + return 0; + + out_release_region: + release_region(smbus->base, smbus->size); + out_kfree: + kfree(smbus); + return error; +} + +static void amd8111_remove(struct pci_dev *dev) +{ + struct amd_smbus *smbus = pci_get_drvdata(dev); + + i2c_del_adapter(&smbus->adapter); + release_region(smbus->base, smbus->size); + kfree(smbus); +} + +static struct pci_driver amd8111_driver = { + .name = "amd8111_smbus2", + .id_table = amd8111_ids, + .probe = amd8111_probe, + .remove = amd8111_remove, +}; + +module_pci_driver(amd8111_driver); diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c new file mode 100644 index 000000000..5511fd46a --- /dev/null +++ b/drivers/i2c/busses/i2c-aspeed.c @@ -0,0 +1,1114 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Aspeed 24XX/25XX I2C Controller. + * + * Copyright (C) 2012-2017 ASPEED Technology Inc. + * Copyright 2017 IBM Corporation + * Copyright 2017 Google, Inc. + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/reset.h> +#include <linux/slab.h> + +/* I2C Register */ +#define ASPEED_I2C_FUN_CTRL_REG 0x00 +#define ASPEED_I2C_AC_TIMING_REG1 0x04 +#define ASPEED_I2C_AC_TIMING_REG2 0x08 +#define ASPEED_I2C_INTR_CTRL_REG 0x0c +#define ASPEED_I2C_INTR_STS_REG 0x10 +#define ASPEED_I2C_CMD_REG 0x14 +#define ASPEED_I2C_DEV_ADDR_REG 0x18 +#define ASPEED_I2C_BYTE_BUF_REG 0x20 + +/* Global Register Definition */ +/* 0x00 : I2C Interrupt Status Register */ +/* 0x08 : I2C Interrupt Target Assignment */ + +/* Device Register Definition */ +/* 0x00 : I2CD Function Control Register */ +#define ASPEED_I2CD_MULTI_MASTER_DIS BIT(15) +#define ASPEED_I2CD_SDA_DRIVE_1T_EN BIT(8) +#define ASPEED_I2CD_M_SDA_DRIVE_1T_EN BIT(7) +#define ASPEED_I2CD_M_HIGH_SPEED_EN BIT(6) +#define ASPEED_I2CD_SLAVE_EN BIT(1) +#define ASPEED_I2CD_MASTER_EN BIT(0) + +/* 0x04 : I2CD Clock and AC Timing Control Register #1 */ +#define ASPEED_I2CD_TIME_TBUF_MASK GENMASK(31, 28) +#define ASPEED_I2CD_TIME_THDSTA_MASK GENMASK(27, 24) +#define ASPEED_I2CD_TIME_TACST_MASK GENMASK(23, 20) +#define ASPEED_I2CD_TIME_SCL_HIGH_SHIFT 16 +#define ASPEED_I2CD_TIME_SCL_HIGH_MASK GENMASK(19, 16) +#define ASPEED_I2CD_TIME_SCL_LOW_SHIFT 12 +#define ASPEED_I2CD_TIME_SCL_LOW_MASK GENMASK(15, 12) +#define ASPEED_I2CD_TIME_BASE_DIVISOR_MASK GENMASK(3, 0) +#define ASPEED_I2CD_TIME_SCL_REG_MAX GENMASK(3, 0) +/* 0x08 : I2CD Clock and AC Timing Control Register #2 */ +#define ASPEED_NO_TIMEOUT_CTRL 0 + +/* 0x0c : I2CD Interrupt Control Register & + * 0x10 : I2CD Interrupt Status Register + * + * These share bit definitions, so use the same values for the enable & + * status bits. + */ +#define ASPEED_I2CD_INTR_RECV_MASK 0xf000ffff +#define ASPEED_I2CD_INTR_SDA_DL_TIMEOUT BIT(14) +#define ASPEED_I2CD_INTR_BUS_RECOVER_DONE BIT(13) +#define ASPEED_I2CD_INTR_SLAVE_MATCH BIT(7) +#define ASPEED_I2CD_INTR_SCL_TIMEOUT BIT(6) +#define ASPEED_I2CD_INTR_ABNORMAL BIT(5) +#define ASPEED_I2CD_INTR_NORMAL_STOP BIT(4) +#define ASPEED_I2CD_INTR_ARBIT_LOSS BIT(3) +#define ASPEED_I2CD_INTR_RX_DONE BIT(2) +#define ASPEED_I2CD_INTR_TX_NAK BIT(1) +#define ASPEED_I2CD_INTR_TX_ACK BIT(0) +#define ASPEED_I2CD_INTR_MASTER_ERRORS \ + (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \ + ASPEED_I2CD_INTR_SCL_TIMEOUT | \ + ASPEED_I2CD_INTR_ABNORMAL | \ + ASPEED_I2CD_INTR_ARBIT_LOSS) +#define ASPEED_I2CD_INTR_ALL \ + (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \ + ASPEED_I2CD_INTR_BUS_RECOVER_DONE | \ + ASPEED_I2CD_INTR_SCL_TIMEOUT | \ + ASPEED_I2CD_INTR_ABNORMAL | \ + ASPEED_I2CD_INTR_NORMAL_STOP | \ + ASPEED_I2CD_INTR_ARBIT_LOSS | \ + ASPEED_I2CD_INTR_RX_DONE | \ + ASPEED_I2CD_INTR_TX_NAK | \ + ASPEED_I2CD_INTR_TX_ACK) + +/* 0x14 : I2CD Command/Status Register */ +#define ASPEED_I2CD_SCL_LINE_STS BIT(18) +#define ASPEED_I2CD_SDA_LINE_STS BIT(17) +#define ASPEED_I2CD_BUS_BUSY_STS BIT(16) +#define ASPEED_I2CD_BUS_RECOVER_CMD BIT(11) + +/* Command Bit */ +#define ASPEED_I2CD_M_STOP_CMD BIT(5) +#define ASPEED_I2CD_M_S_RX_CMD_LAST BIT(4) +#define ASPEED_I2CD_M_RX_CMD BIT(3) +#define ASPEED_I2CD_S_TX_CMD BIT(2) +#define ASPEED_I2CD_M_TX_CMD BIT(1) +#define ASPEED_I2CD_M_START_CMD BIT(0) +#define ASPEED_I2CD_MASTER_CMDS_MASK \ + (ASPEED_I2CD_M_STOP_CMD | \ + ASPEED_I2CD_M_S_RX_CMD_LAST | \ + ASPEED_I2CD_M_RX_CMD | \ + ASPEED_I2CD_M_TX_CMD | \ + ASPEED_I2CD_M_START_CMD) + +/* 0x18 : I2CD Slave Device Address Register */ +#define ASPEED_I2CD_DEV_ADDR_MASK GENMASK(6, 0) + +enum aspeed_i2c_master_state { + ASPEED_I2C_MASTER_INACTIVE, + ASPEED_I2C_MASTER_PENDING, + ASPEED_I2C_MASTER_START, + ASPEED_I2C_MASTER_TX_FIRST, + ASPEED_I2C_MASTER_TX, + ASPEED_I2C_MASTER_RX_FIRST, + ASPEED_I2C_MASTER_RX, + ASPEED_I2C_MASTER_STOP, +}; + +enum aspeed_i2c_slave_state { + ASPEED_I2C_SLAVE_INACTIVE, + ASPEED_I2C_SLAVE_START, + ASPEED_I2C_SLAVE_READ_REQUESTED, + ASPEED_I2C_SLAVE_READ_PROCESSED, + ASPEED_I2C_SLAVE_WRITE_REQUESTED, + ASPEED_I2C_SLAVE_WRITE_RECEIVED, + ASPEED_I2C_SLAVE_STOP, +}; + +struct aspeed_i2c_bus { + struct i2c_adapter adap; + struct device *dev; + void __iomem *base; + struct reset_control *rst; + /* Synchronizes I/O mem access to base. */ + spinlock_t lock; + struct completion cmd_complete; + u32 (*get_clk_reg_val)(struct device *dev, + u32 divisor); + unsigned long parent_clk_frequency; + u32 bus_frequency; + /* Transaction state. */ + enum aspeed_i2c_master_state master_state; + struct i2c_msg *msgs; + size_t buf_index; + size_t msgs_index; + size_t msgs_count; + bool send_stop; + int cmd_err; + /* Protected only by i2c_lock_bus */ + int master_xfer_result; + /* Multi-master */ + bool multi_master; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + struct i2c_client *slave; + enum aspeed_i2c_slave_state slave_state; +#endif /* CONFIG_I2C_SLAVE */ +}; + +static int aspeed_i2c_reset(struct aspeed_i2c_bus *bus); + +static int aspeed_i2c_recover_bus(struct aspeed_i2c_bus *bus) +{ + unsigned long time_left, flags; + int ret = 0; + u32 command; + + spin_lock_irqsave(&bus->lock, flags); + command = readl(bus->base + ASPEED_I2C_CMD_REG); + + if (command & ASPEED_I2CD_SDA_LINE_STS) { + /* Bus is idle: no recovery needed. */ + if (command & ASPEED_I2CD_SCL_LINE_STS) + goto out; + dev_dbg(bus->dev, "SCL hung (state %x), attempting recovery\n", + command); + + reinit_completion(&bus->cmd_complete); + writel(ASPEED_I2CD_M_STOP_CMD, bus->base + ASPEED_I2C_CMD_REG); + spin_unlock_irqrestore(&bus->lock, flags); + + time_left = wait_for_completion_timeout( + &bus->cmd_complete, bus->adap.timeout); + + spin_lock_irqsave(&bus->lock, flags); + if (time_left == 0) + goto reset_out; + else if (bus->cmd_err) + goto reset_out; + /* Recovery failed. */ + else if (!(readl(bus->base + ASPEED_I2C_CMD_REG) & + ASPEED_I2CD_SCL_LINE_STS)) + goto reset_out; + /* Bus error. */ + } else { + dev_dbg(bus->dev, "SDA hung (state %x), attempting recovery\n", + command); + + reinit_completion(&bus->cmd_complete); + /* Writes 1 to 8 SCL clock cycles until SDA is released. */ + writel(ASPEED_I2CD_BUS_RECOVER_CMD, + bus->base + ASPEED_I2C_CMD_REG); + spin_unlock_irqrestore(&bus->lock, flags); + + time_left = wait_for_completion_timeout( + &bus->cmd_complete, bus->adap.timeout); + + spin_lock_irqsave(&bus->lock, flags); + if (time_left == 0) + goto reset_out; + else if (bus->cmd_err) + goto reset_out; + /* Recovery failed. */ + else if (!(readl(bus->base + ASPEED_I2C_CMD_REG) & + ASPEED_I2CD_SDA_LINE_STS)) + goto reset_out; + } + +out: + spin_unlock_irqrestore(&bus->lock, flags); + + return ret; + +reset_out: + spin_unlock_irqrestore(&bus->lock, flags); + + return aspeed_i2c_reset(bus); +} + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status) +{ + u32 command, irq_handled = 0; + struct i2c_client *slave = bus->slave; + u8 value; + int ret; + + if (!slave) + return 0; + + /* + * Handle stop conditions early, prior to SLAVE_MATCH. Some masters may drive + * transfers with low enough latency between the nak/stop phase of the current + * command and the start/address phase of the following command that the + * interrupts are coalesced by the time we process them. + */ + if (irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) { + irq_handled |= ASPEED_I2CD_INTR_NORMAL_STOP; + bus->slave_state = ASPEED_I2C_SLAVE_STOP; + } + + if (irq_status & ASPEED_I2CD_INTR_TX_NAK && + bus->slave_state == ASPEED_I2C_SLAVE_READ_PROCESSED) { + irq_handled |= ASPEED_I2CD_INTR_TX_NAK; + bus->slave_state = ASPEED_I2C_SLAVE_STOP; + } + + /* Propagate any stop conditions to the slave implementation. */ + if (bus->slave_state == ASPEED_I2C_SLAVE_STOP) { + i2c_slave_event(slave, I2C_SLAVE_STOP, &value); + bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE; + } + + /* + * Now that we've dealt with any potentially coalesced stop conditions, + * address any start conditions. + */ + if (irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH) { + irq_handled |= ASPEED_I2CD_INTR_SLAVE_MATCH; + bus->slave_state = ASPEED_I2C_SLAVE_START; + } + + /* + * If the slave has been stopped and not started then slave interrupt + * handling is complete. + */ + if (bus->slave_state == ASPEED_I2C_SLAVE_INACTIVE) + return irq_handled; + + command = readl(bus->base + ASPEED_I2C_CMD_REG); + dev_dbg(bus->dev, "slave irq status 0x%08x, cmd 0x%08x\n", + irq_status, command); + + /* Slave was sent something. */ + if (irq_status & ASPEED_I2CD_INTR_RX_DONE) { + value = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8; + /* Handle address frame. */ + if (bus->slave_state == ASPEED_I2C_SLAVE_START) { + if (value & 0x1) + bus->slave_state = + ASPEED_I2C_SLAVE_READ_REQUESTED; + else + bus->slave_state = + ASPEED_I2C_SLAVE_WRITE_REQUESTED; + } + irq_handled |= ASPEED_I2CD_INTR_RX_DONE; + } + + switch (bus->slave_state) { + case ASPEED_I2C_SLAVE_READ_REQUESTED: + if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_ACK)) + dev_err(bus->dev, "Unexpected ACK on read request.\n"); + bus->slave_state = ASPEED_I2C_SLAVE_READ_PROCESSED; + i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value); + writel(value, bus->base + ASPEED_I2C_BYTE_BUF_REG); + writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG); + break; + case ASPEED_I2C_SLAVE_READ_PROCESSED: + if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) { + dev_err(bus->dev, + "Expected ACK after processed read.\n"); + break; + } + irq_handled |= ASPEED_I2CD_INTR_TX_ACK; + i2c_slave_event(slave, I2C_SLAVE_READ_PROCESSED, &value); + writel(value, bus->base + ASPEED_I2C_BYTE_BUF_REG); + writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG); + break; + case ASPEED_I2C_SLAVE_WRITE_REQUESTED: + bus->slave_state = ASPEED_I2C_SLAVE_WRITE_RECEIVED; + ret = i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value); + /* + * Slave ACK's on this address phase already but as the backend driver + * returns an errno, the bus driver should nack the next incoming byte. + */ + if (ret < 0) + writel(ASPEED_I2CD_M_S_RX_CMD_LAST, bus->base + ASPEED_I2C_CMD_REG); + break; + case ASPEED_I2C_SLAVE_WRITE_RECEIVED: + i2c_slave_event(slave, I2C_SLAVE_WRITE_RECEIVED, &value); + break; + case ASPEED_I2C_SLAVE_STOP: + /* Stop event handling is done early. Unreachable. */ + break; + case ASPEED_I2C_SLAVE_START: + /* Slave was just started. Waiting for the next event. */; + break; + default: + dev_err(bus->dev, "unknown slave_state: %d\n", + bus->slave_state); + bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE; + break; + } + + return irq_handled; +} +#endif /* CONFIG_I2C_SLAVE */ + +/* precondition: bus.lock has been acquired. */ +static void aspeed_i2c_do_start(struct aspeed_i2c_bus *bus) +{ + u32 command = ASPEED_I2CD_M_START_CMD | ASPEED_I2CD_M_TX_CMD; + struct i2c_msg *msg = &bus->msgs[bus->msgs_index]; + u8 slave_addr = i2c_8bit_addr_from_msg(msg); + +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* + * If it's requested in the middle of a slave session, set the master + * state to 'pending' then H/W will continue handling this master + * command when the bus comes back to the idle state. + */ + if (bus->slave_state != ASPEED_I2C_SLAVE_INACTIVE) { + bus->master_state = ASPEED_I2C_MASTER_PENDING; + return; + } +#endif /* CONFIG_I2C_SLAVE */ + + bus->master_state = ASPEED_I2C_MASTER_START; + bus->buf_index = 0; + + if (msg->flags & I2C_M_RD) { + command |= ASPEED_I2CD_M_RX_CMD; + /* Need to let the hardware know to NACK after RX. */ + if (msg->len == 1 && !(msg->flags & I2C_M_RECV_LEN)) + command |= ASPEED_I2CD_M_S_RX_CMD_LAST; + } + + writel(slave_addr, bus->base + ASPEED_I2C_BYTE_BUF_REG); + writel(command, bus->base + ASPEED_I2C_CMD_REG); +} + +/* precondition: bus.lock has been acquired. */ +static void aspeed_i2c_do_stop(struct aspeed_i2c_bus *bus) +{ + bus->master_state = ASPEED_I2C_MASTER_STOP; + writel(ASPEED_I2CD_M_STOP_CMD, bus->base + ASPEED_I2C_CMD_REG); +} + +/* precondition: bus.lock has been acquired. */ +static void aspeed_i2c_next_msg_or_stop(struct aspeed_i2c_bus *bus) +{ + if (bus->msgs_index + 1 < bus->msgs_count) { + bus->msgs_index++; + aspeed_i2c_do_start(bus); + } else { + aspeed_i2c_do_stop(bus); + } +} + +static int aspeed_i2c_is_irq_error(u32 irq_status) +{ + if (irq_status & ASPEED_I2CD_INTR_ARBIT_LOSS) + return -EAGAIN; + if (irq_status & (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | + ASPEED_I2CD_INTR_SCL_TIMEOUT)) + return -EBUSY; + if (irq_status & (ASPEED_I2CD_INTR_ABNORMAL)) + return -EPROTO; + + return 0; +} + +static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status) +{ + u32 irq_handled = 0, command = 0; + struct i2c_msg *msg; + u8 recv_byte; + int ret; + + if (irq_status & ASPEED_I2CD_INTR_BUS_RECOVER_DONE) { + bus->master_state = ASPEED_I2C_MASTER_INACTIVE; + irq_handled |= ASPEED_I2CD_INTR_BUS_RECOVER_DONE; + goto out_complete; + } + + /* + * We encountered an interrupt that reports an error: the hardware + * should clear the command queue effectively taking us back to the + * INACTIVE state. + */ + ret = aspeed_i2c_is_irq_error(irq_status); + if (ret) { + dev_dbg(bus->dev, "received error interrupt: 0x%08x\n", + irq_status); + irq_handled |= (irq_status & ASPEED_I2CD_INTR_MASTER_ERRORS); + if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE) { + bus->cmd_err = ret; + bus->master_state = ASPEED_I2C_MASTER_INACTIVE; + goto out_complete; + } + } + + /* Master is not currently active, irq was for someone else. */ + if (bus->master_state == ASPEED_I2C_MASTER_INACTIVE || + bus->master_state == ASPEED_I2C_MASTER_PENDING) + goto out_no_complete; + + /* We are in an invalid state; reset bus to a known state. */ + if (!bus->msgs) { + dev_err(bus->dev, "bus in unknown state. irq_status: 0x%x\n", + irq_status); + bus->cmd_err = -EIO; + if (bus->master_state != ASPEED_I2C_MASTER_STOP && + bus->master_state != ASPEED_I2C_MASTER_INACTIVE) + aspeed_i2c_do_stop(bus); + goto out_no_complete; + } + msg = &bus->msgs[bus->msgs_index]; + + /* + * START is a special case because we still have to handle a subsequent + * TX or RX immediately after we handle it, so we handle it here and + * then update the state and handle the new state below. + */ + if (bus->master_state == ASPEED_I2C_MASTER_START) { +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* + * If a peer master starts a xfer immediately after it queues a + * master command, clear the queued master command and change + * its state to 'pending'. To simplify handling of pending + * cases, it uses S/W solution instead of H/W command queue + * handling. + */ + if (unlikely(irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH)) { + writel(readl(bus->base + ASPEED_I2C_CMD_REG) & + ~ASPEED_I2CD_MASTER_CMDS_MASK, + bus->base + ASPEED_I2C_CMD_REG); + bus->master_state = ASPEED_I2C_MASTER_PENDING; + dev_dbg(bus->dev, + "master goes pending due to a slave start\n"); + goto out_no_complete; + } +#endif /* CONFIG_I2C_SLAVE */ + if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) { + if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_NAK))) { + bus->cmd_err = -ENXIO; + bus->master_state = ASPEED_I2C_MASTER_INACTIVE; + goto out_complete; + } + pr_devel("no slave present at %02x\n", msg->addr); + irq_handled |= ASPEED_I2CD_INTR_TX_NAK; + bus->cmd_err = -ENXIO; + aspeed_i2c_do_stop(bus); + goto out_no_complete; + } + irq_handled |= ASPEED_I2CD_INTR_TX_ACK; + if (msg->len == 0) { /* SMBUS_QUICK */ + aspeed_i2c_do_stop(bus); + goto out_no_complete; + } + if (msg->flags & I2C_M_RD) + bus->master_state = ASPEED_I2C_MASTER_RX_FIRST; + else + bus->master_state = ASPEED_I2C_MASTER_TX_FIRST; + } + + switch (bus->master_state) { + case ASPEED_I2C_MASTER_TX: + if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_NAK)) { + dev_dbg(bus->dev, "slave NACKed TX\n"); + irq_handled |= ASPEED_I2CD_INTR_TX_NAK; + goto error_and_stop; + } else if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) { + dev_err(bus->dev, "slave failed to ACK TX\n"); + goto error_and_stop; + } + irq_handled |= ASPEED_I2CD_INTR_TX_ACK; + fallthrough; + case ASPEED_I2C_MASTER_TX_FIRST: + if (bus->buf_index < msg->len) { + bus->master_state = ASPEED_I2C_MASTER_TX; + writel(msg->buf[bus->buf_index++], + bus->base + ASPEED_I2C_BYTE_BUF_REG); + writel(ASPEED_I2CD_M_TX_CMD, + bus->base + ASPEED_I2C_CMD_REG); + } else { + aspeed_i2c_next_msg_or_stop(bus); + } + goto out_no_complete; + case ASPEED_I2C_MASTER_RX_FIRST: + /* RX may not have completed yet (only address cycle) */ + if (!(irq_status & ASPEED_I2CD_INTR_RX_DONE)) + goto out_no_complete; + fallthrough; + case ASPEED_I2C_MASTER_RX: + if (unlikely(!(irq_status & ASPEED_I2CD_INTR_RX_DONE))) { + dev_err(bus->dev, "master failed to RX\n"); + goto error_and_stop; + } + irq_handled |= ASPEED_I2CD_INTR_RX_DONE; + + recv_byte = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8; + msg->buf[bus->buf_index++] = recv_byte; + + if (msg->flags & I2C_M_RECV_LEN) { + if (unlikely(recv_byte > I2C_SMBUS_BLOCK_MAX)) { + bus->cmd_err = -EPROTO; + aspeed_i2c_do_stop(bus); + goto out_no_complete; + } + msg->len = recv_byte + + ((msg->flags & I2C_CLIENT_PEC) ? 2 : 1); + msg->flags &= ~I2C_M_RECV_LEN; + } + + if (bus->buf_index < msg->len) { + bus->master_state = ASPEED_I2C_MASTER_RX; + command = ASPEED_I2CD_M_RX_CMD; + if (bus->buf_index + 1 == msg->len) + command |= ASPEED_I2CD_M_S_RX_CMD_LAST; + writel(command, bus->base + ASPEED_I2C_CMD_REG); + } else { + aspeed_i2c_next_msg_or_stop(bus); + } + goto out_no_complete; + case ASPEED_I2C_MASTER_STOP: + if (unlikely(!(irq_status & ASPEED_I2CD_INTR_NORMAL_STOP))) { + dev_err(bus->dev, + "master failed to STOP. irq_status:0x%x\n", + irq_status); + bus->cmd_err = -EIO; + /* Do not STOP as we have already tried. */ + } else { + irq_handled |= ASPEED_I2CD_INTR_NORMAL_STOP; + } + + bus->master_state = ASPEED_I2C_MASTER_INACTIVE; + goto out_complete; + case ASPEED_I2C_MASTER_INACTIVE: + dev_err(bus->dev, + "master received interrupt 0x%08x, but is inactive\n", + irq_status); + bus->cmd_err = -EIO; + /* Do not STOP as we should be inactive. */ + goto out_complete; + default: + WARN(1, "unknown master state\n"); + bus->master_state = ASPEED_I2C_MASTER_INACTIVE; + bus->cmd_err = -EINVAL; + goto out_complete; + } +error_and_stop: + bus->cmd_err = -EIO; + aspeed_i2c_do_stop(bus); + goto out_no_complete; +out_complete: + bus->msgs = NULL; + if (bus->cmd_err) + bus->master_xfer_result = bus->cmd_err; + else + bus->master_xfer_result = bus->msgs_index + 1; + complete(&bus->cmd_complete); +out_no_complete: + return irq_handled; +} + +static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id) +{ + struct aspeed_i2c_bus *bus = dev_id; + u32 irq_received, irq_remaining, irq_handled; + + spin_lock(&bus->lock); + irq_received = readl(bus->base + ASPEED_I2C_INTR_STS_REG); + /* Ack all interrupts except for Rx done */ + writel(irq_received & ~ASPEED_I2CD_INTR_RX_DONE, + bus->base + ASPEED_I2C_INTR_STS_REG); + readl(bus->base + ASPEED_I2C_INTR_STS_REG); + irq_received &= ASPEED_I2CD_INTR_RECV_MASK; + irq_remaining = irq_received; + +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* + * In most cases, interrupt bits will be set one by one, although + * multiple interrupt bits could be set at the same time. It's also + * possible that master interrupt bits could be set along with slave + * interrupt bits. Each case needs to be handled using corresponding + * handlers depending on the current state. + */ + if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE && + bus->master_state != ASPEED_I2C_MASTER_PENDING) { + irq_handled = aspeed_i2c_master_irq(bus, irq_remaining); + irq_remaining &= ~irq_handled; + if (irq_remaining) + irq_handled |= aspeed_i2c_slave_irq(bus, irq_remaining); + } else { + irq_handled = aspeed_i2c_slave_irq(bus, irq_remaining); + irq_remaining &= ~irq_handled; + if (irq_remaining) + irq_handled |= aspeed_i2c_master_irq(bus, + irq_remaining); + } + + /* + * Start a pending master command at here if a slave operation is + * completed. + */ + if (bus->master_state == ASPEED_I2C_MASTER_PENDING && + bus->slave_state == ASPEED_I2C_SLAVE_INACTIVE) + aspeed_i2c_do_start(bus); +#else + irq_handled = aspeed_i2c_master_irq(bus, irq_remaining); +#endif /* CONFIG_I2C_SLAVE */ + + irq_remaining &= ~irq_handled; + if (irq_remaining) + dev_err(bus->dev, + "irq handled != irq. expected 0x%08x, but was 0x%08x\n", + irq_received, irq_handled); + + /* Ack Rx done */ + if (irq_received & ASPEED_I2CD_INTR_RX_DONE) { + writel(ASPEED_I2CD_INTR_RX_DONE, + bus->base + ASPEED_I2C_INTR_STS_REG); + readl(bus->base + ASPEED_I2C_INTR_STS_REG); + } + spin_unlock(&bus->lock); + return irq_remaining ? IRQ_NONE : IRQ_HANDLED; +} + +static int aspeed_i2c_master_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct aspeed_i2c_bus *bus = i2c_get_adapdata(adap); + unsigned long time_left, flags; + + spin_lock_irqsave(&bus->lock, flags); + bus->cmd_err = 0; + + /* If bus is busy in a single master environment, attempt recovery. */ + if (!bus->multi_master && + (readl(bus->base + ASPEED_I2C_CMD_REG) & + ASPEED_I2CD_BUS_BUSY_STS)) { + int ret; + + spin_unlock_irqrestore(&bus->lock, flags); + ret = aspeed_i2c_recover_bus(bus); + if (ret) + return ret; + spin_lock_irqsave(&bus->lock, flags); + } + + bus->cmd_err = 0; + bus->msgs = msgs; + bus->msgs_index = 0; + bus->msgs_count = num; + + reinit_completion(&bus->cmd_complete); + aspeed_i2c_do_start(bus); + spin_unlock_irqrestore(&bus->lock, flags); + + time_left = wait_for_completion_timeout(&bus->cmd_complete, + bus->adap.timeout); + + if (time_left == 0) { + /* + * In a multi-master setup, if a timeout occurs, attempt + * recovery. But if the bus is idle, we still need to reset the + * i2c controller to clear the remaining interrupts. + */ + if (bus->multi_master && + (readl(bus->base + ASPEED_I2C_CMD_REG) & + ASPEED_I2CD_BUS_BUSY_STS)) + aspeed_i2c_recover_bus(bus); + else + aspeed_i2c_reset(bus); + + /* + * If timed out and the state is still pending, drop the pending + * master command. + */ + spin_lock_irqsave(&bus->lock, flags); + if (bus->master_state == ASPEED_I2C_MASTER_PENDING) + bus->master_state = ASPEED_I2C_MASTER_INACTIVE; + spin_unlock_irqrestore(&bus->lock, flags); + + return -ETIMEDOUT; + } + + return bus->master_xfer_result; +} + +static u32 aspeed_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_BLOCK_DATA; +} + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +/* precondition: bus.lock has been acquired. */ +static void __aspeed_i2c_reg_slave(struct aspeed_i2c_bus *bus, u16 slave_addr) +{ + u32 addr_reg_val, func_ctrl_reg_val; + + /* + * Set slave addr. Reserved bits can all safely be written with zeros + * on all of ast2[456]00, so zero everything else to ensure we only + * enable a single slave address (ast2500 has two, ast2600 has three, + * the enable bits for which are also in this register) so that we don't + * end up with additional phantom devices responding on the bus. + */ + addr_reg_val = slave_addr & ASPEED_I2CD_DEV_ADDR_MASK; + writel(addr_reg_val, bus->base + ASPEED_I2C_DEV_ADDR_REG); + + /* Turn on slave mode. */ + func_ctrl_reg_val = readl(bus->base + ASPEED_I2C_FUN_CTRL_REG); + func_ctrl_reg_val |= ASPEED_I2CD_SLAVE_EN; + writel(func_ctrl_reg_val, bus->base + ASPEED_I2C_FUN_CTRL_REG); + + bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE; +} + +static int aspeed_i2c_reg_slave(struct i2c_client *client) +{ + struct aspeed_i2c_bus *bus = i2c_get_adapdata(client->adapter); + unsigned long flags; + + spin_lock_irqsave(&bus->lock, flags); + if (bus->slave) { + spin_unlock_irqrestore(&bus->lock, flags); + return -EINVAL; + } + + __aspeed_i2c_reg_slave(bus, client->addr); + + bus->slave = client; + spin_unlock_irqrestore(&bus->lock, flags); + + return 0; +} + +static int aspeed_i2c_unreg_slave(struct i2c_client *client) +{ + struct aspeed_i2c_bus *bus = i2c_get_adapdata(client->adapter); + u32 func_ctrl_reg_val; + unsigned long flags; + + spin_lock_irqsave(&bus->lock, flags); + if (!bus->slave) { + spin_unlock_irqrestore(&bus->lock, flags); + return -EINVAL; + } + + /* Turn off slave mode. */ + func_ctrl_reg_val = readl(bus->base + ASPEED_I2C_FUN_CTRL_REG); + func_ctrl_reg_val &= ~ASPEED_I2CD_SLAVE_EN; + writel(func_ctrl_reg_val, bus->base + ASPEED_I2C_FUN_CTRL_REG); + + bus->slave = NULL; + spin_unlock_irqrestore(&bus->lock, flags); + + return 0; +} +#endif /* CONFIG_I2C_SLAVE */ + +static const struct i2c_algorithm aspeed_i2c_algo = { + .master_xfer = aspeed_i2c_master_xfer, + .functionality = aspeed_i2c_functionality, +#if IS_ENABLED(CONFIG_I2C_SLAVE) + .reg_slave = aspeed_i2c_reg_slave, + .unreg_slave = aspeed_i2c_unreg_slave, +#endif /* CONFIG_I2C_SLAVE */ +}; + +static u32 aspeed_i2c_get_clk_reg_val(struct device *dev, + u32 clk_high_low_mask, + u32 divisor) +{ + u32 base_clk_divisor, clk_high_low_max, clk_high, clk_low, tmp; + + /* + * SCL_high and SCL_low represent a value 1 greater than what is stored + * since a zero divider is meaningless. Thus, the max value each can + * store is every bit set + 1. Since SCL_high and SCL_low are added + * together (see below), the max value of both is the max value of one + * them times two. + */ + clk_high_low_max = (clk_high_low_mask + 1) * 2; + + /* + * The actual clock frequency of SCL is: + * SCL_freq = APB_freq / (base_freq * (SCL_high + SCL_low)) + * = APB_freq / divisor + * where base_freq is a programmable clock divider; its value is + * base_freq = 1 << base_clk_divisor + * SCL_high is the number of base_freq clock cycles that SCL stays high + * and SCL_low is the number of base_freq clock cycles that SCL stays + * low for a period of SCL. + * The actual register has a minimum SCL_high and SCL_low minimum of 1; + * thus, they start counting at zero. So + * SCL_high = clk_high + 1 + * SCL_low = clk_low + 1 + * Thus, + * SCL_freq = APB_freq / + * ((1 << base_clk_divisor) * (clk_high + 1 + clk_low + 1)) + * The documentation recommends clk_high >= clk_high_max / 2 and + * clk_low >= clk_low_max / 2 - 1 when possible; this last constraint + * gives us the following solution: + */ + base_clk_divisor = divisor > clk_high_low_max ? + ilog2((divisor - 1) / clk_high_low_max) + 1 : 0; + + if (base_clk_divisor > ASPEED_I2CD_TIME_BASE_DIVISOR_MASK) { + base_clk_divisor = ASPEED_I2CD_TIME_BASE_DIVISOR_MASK; + clk_low = clk_high_low_mask; + clk_high = clk_high_low_mask; + dev_err(dev, + "clamping clock divider: divider requested, %u, is greater than largest possible divider, %u.\n", + divisor, (1 << base_clk_divisor) * clk_high_low_max); + } else { + tmp = (divisor + (1 << base_clk_divisor) - 1) + >> base_clk_divisor; + clk_low = tmp / 2; + clk_high = tmp - clk_low; + + if (clk_high) + clk_high--; + + if (clk_low) + clk_low--; + } + + + return ((clk_high << ASPEED_I2CD_TIME_SCL_HIGH_SHIFT) + & ASPEED_I2CD_TIME_SCL_HIGH_MASK) + | ((clk_low << ASPEED_I2CD_TIME_SCL_LOW_SHIFT) + & ASPEED_I2CD_TIME_SCL_LOW_MASK) + | (base_clk_divisor + & ASPEED_I2CD_TIME_BASE_DIVISOR_MASK); +} + +static u32 aspeed_i2c_24xx_get_clk_reg_val(struct device *dev, u32 divisor) +{ + /* + * clk_high and clk_low are each 3 bits wide, so each can hold a max + * value of 8 giving a clk_high_low_max of 16. + */ + return aspeed_i2c_get_clk_reg_val(dev, GENMASK(2, 0), divisor); +} + +static u32 aspeed_i2c_25xx_get_clk_reg_val(struct device *dev, u32 divisor) +{ + /* + * clk_high and clk_low are each 4 bits wide, so each can hold a max + * value of 16 giving a clk_high_low_max of 32. + */ + return aspeed_i2c_get_clk_reg_val(dev, GENMASK(3, 0), divisor); +} + +/* precondition: bus.lock has been acquired. */ +static int aspeed_i2c_init_clk(struct aspeed_i2c_bus *bus) +{ + u32 divisor, clk_reg_val; + + divisor = DIV_ROUND_UP(bus->parent_clk_frequency, bus->bus_frequency); + clk_reg_val = readl(bus->base + ASPEED_I2C_AC_TIMING_REG1); + clk_reg_val &= (ASPEED_I2CD_TIME_TBUF_MASK | + ASPEED_I2CD_TIME_THDSTA_MASK | + ASPEED_I2CD_TIME_TACST_MASK); + clk_reg_val |= bus->get_clk_reg_val(bus->dev, divisor); + writel(clk_reg_val, bus->base + ASPEED_I2C_AC_TIMING_REG1); + writel(ASPEED_NO_TIMEOUT_CTRL, bus->base + ASPEED_I2C_AC_TIMING_REG2); + + return 0; +} + +/* precondition: bus.lock has been acquired. */ +static int aspeed_i2c_init(struct aspeed_i2c_bus *bus, + struct platform_device *pdev) +{ + u32 fun_ctrl_reg = ASPEED_I2CD_MASTER_EN; + int ret; + + /* Disable everything. */ + writel(0, bus->base + ASPEED_I2C_FUN_CTRL_REG); + + ret = aspeed_i2c_init_clk(bus); + if (ret < 0) + return ret; + + if (of_property_read_bool(pdev->dev.of_node, "multi-master")) + bus->multi_master = true; + else + fun_ctrl_reg |= ASPEED_I2CD_MULTI_MASTER_DIS; + + /* Enable Master Mode */ + writel(readl(bus->base + ASPEED_I2C_FUN_CTRL_REG) | fun_ctrl_reg, + bus->base + ASPEED_I2C_FUN_CTRL_REG); + +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* If slave has already been registered, re-enable it. */ + if (bus->slave) + __aspeed_i2c_reg_slave(bus, bus->slave->addr); +#endif /* CONFIG_I2C_SLAVE */ + + /* Set interrupt generation of I2C controller */ + writel(ASPEED_I2CD_INTR_ALL, bus->base + ASPEED_I2C_INTR_CTRL_REG); + + return 0; +} + +static int aspeed_i2c_reset(struct aspeed_i2c_bus *bus) +{ + struct platform_device *pdev = to_platform_device(bus->dev); + unsigned long flags; + int ret; + + spin_lock_irqsave(&bus->lock, flags); + + /* Disable and ack all interrupts. */ + writel(0, bus->base + ASPEED_I2C_INTR_CTRL_REG); + writel(0xffffffff, bus->base + ASPEED_I2C_INTR_STS_REG); + + ret = aspeed_i2c_init(bus, pdev); + + spin_unlock_irqrestore(&bus->lock, flags); + + return ret; +} + +static const struct of_device_id aspeed_i2c_bus_of_table[] = { + { + .compatible = "aspeed,ast2400-i2c-bus", + .data = aspeed_i2c_24xx_get_clk_reg_val, + }, + { + .compatible = "aspeed,ast2500-i2c-bus", + .data = aspeed_i2c_25xx_get_clk_reg_val, + }, + { + .compatible = "aspeed,ast2600-i2c-bus", + .data = aspeed_i2c_25xx_get_clk_reg_val, + }, + { }, +}; +MODULE_DEVICE_TABLE(of, aspeed_i2c_bus_of_table); + +static int aspeed_i2c_probe_bus(struct platform_device *pdev) +{ + const struct of_device_id *match; + struct aspeed_i2c_bus *bus; + struct clk *parent_clk; + int irq, ret; + + bus = devm_kzalloc(&pdev->dev, sizeof(*bus), GFP_KERNEL); + if (!bus) + return -ENOMEM; + + bus->base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(bus->base)) + return PTR_ERR(bus->base); + + parent_clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(parent_clk)) + return PTR_ERR(parent_clk); + bus->parent_clk_frequency = clk_get_rate(parent_clk); + /* We just need the clock rate, we don't actually use the clk object. */ + devm_clk_put(&pdev->dev, parent_clk); + + bus->rst = devm_reset_control_get_shared(&pdev->dev, NULL); + if (IS_ERR(bus->rst)) { + dev_err(&pdev->dev, + "missing or invalid reset controller device tree entry\n"); + return PTR_ERR(bus->rst); + } + reset_control_deassert(bus->rst); + + ret = of_property_read_u32(pdev->dev.of_node, + "bus-frequency", &bus->bus_frequency); + if (ret < 0) { + dev_err(&pdev->dev, + "Could not read bus-frequency property\n"); + bus->bus_frequency = I2C_MAX_STANDARD_MODE_FREQ; + } + + match = of_match_node(aspeed_i2c_bus_of_table, pdev->dev.of_node); + if (!match) + bus->get_clk_reg_val = aspeed_i2c_24xx_get_clk_reg_val; + else + bus->get_clk_reg_val = (u32 (*)(struct device *, u32)) + match->data; + + /* Initialize the I2C adapter */ + spin_lock_init(&bus->lock); + init_completion(&bus->cmd_complete); + bus->adap.owner = THIS_MODULE; + bus->adap.retries = 0; + bus->adap.algo = &aspeed_i2c_algo; + bus->adap.dev.parent = &pdev->dev; + bus->adap.dev.of_node = pdev->dev.of_node; + strscpy(bus->adap.name, pdev->name, sizeof(bus->adap.name)); + i2c_set_adapdata(&bus->adap, bus); + + bus->dev = &pdev->dev; + + /* Clean up any left over interrupt state. */ + writel(0, bus->base + ASPEED_I2C_INTR_CTRL_REG); + writel(0xffffffff, bus->base + ASPEED_I2C_INTR_STS_REG); + /* + * bus.lock does not need to be held because the interrupt handler has + * not been enabled yet. + */ + ret = aspeed_i2c_init(bus, pdev); + if (ret < 0) + return ret; + + irq = irq_of_parse_and_map(pdev->dev.of_node, 0); + ret = devm_request_irq(&pdev->dev, irq, aspeed_i2c_bus_irq, + 0, dev_name(&pdev->dev), bus); + if (ret < 0) + return ret; + + ret = i2c_add_adapter(&bus->adap); + if (ret < 0) + return ret; + + platform_set_drvdata(pdev, bus); + + dev_info(bus->dev, "i2c bus %d registered, irq %d\n", + bus->adap.nr, irq); + + return 0; +} + +static void aspeed_i2c_remove_bus(struct platform_device *pdev) +{ + struct aspeed_i2c_bus *bus = platform_get_drvdata(pdev); + unsigned long flags; + + spin_lock_irqsave(&bus->lock, flags); + + /* Disable everything. */ + writel(0, bus->base + ASPEED_I2C_FUN_CTRL_REG); + writel(0, bus->base + ASPEED_I2C_INTR_CTRL_REG); + + spin_unlock_irqrestore(&bus->lock, flags); + + reset_control_assert(bus->rst); + + i2c_del_adapter(&bus->adap); +} + +static struct platform_driver aspeed_i2c_bus_driver = { + .probe = aspeed_i2c_probe_bus, + .remove_new = aspeed_i2c_remove_bus, + .driver = { + .name = "aspeed-i2c-bus", + .of_match_table = aspeed_i2c_bus_of_table, + }, +}; +module_platform_driver(aspeed_i2c_bus_driver); + +MODULE_AUTHOR("Brendan Higgins <brendanhiggins@google.com>"); +MODULE_DESCRIPTION("Aspeed I2C Bus Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-at91-core.c b/drivers/i2c/busses/i2c-at91-core.c new file mode 100644 index 000000000..db4555432 --- /dev/null +++ b/drivers/i2c/busses/i2c-at91-core.c @@ -0,0 +1,362 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * i2c Support for Atmel's AT91 Two-Wire Interface (TWI) + * + * Copyright (C) 2011 Weinmann Medical GmbH + * Author: Nikolaus Voss <n.voss@weinmann.de> + * + * Evolved from original work by: + * Copyright (C) 2004 Rick Bronson + * Converted to 2.6 by Andrew Victor <andrew@sanpeople.com> + * + * Borrowed heavily from original work by: + * Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com> + */ + +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/pinctrl/consumer.h> + +#include "i2c-at91.h" + +unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg) +{ + return readl_relaxed(dev->base + reg); +} + +void at91_twi_write(struct at91_twi_dev *dev, unsigned reg, unsigned val) +{ + writel_relaxed(val, dev->base + reg); +} + +void at91_disable_twi_interrupts(struct at91_twi_dev *dev) +{ + at91_twi_write(dev, AT91_TWI_IDR, AT91_TWI_INT_MASK); +} + +void at91_twi_irq_save(struct at91_twi_dev *dev) +{ + dev->imr = at91_twi_read(dev, AT91_TWI_IMR) & AT91_TWI_INT_MASK; + at91_disable_twi_interrupts(dev); +} + +void at91_twi_irq_restore(struct at91_twi_dev *dev) +{ + at91_twi_write(dev, AT91_TWI_IER, dev->imr); +} + +void at91_init_twi_bus(struct at91_twi_dev *dev) +{ + at91_disable_twi_interrupts(dev); + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SWRST); + if (dev->slave_detected) + at91_init_twi_bus_slave(dev); + else + at91_init_twi_bus_master(dev); +} + +static struct at91_twi_pdata at91rm9200_config = { + .clk_max_div = 5, + .clk_offset = 3, + .has_unre_flag = true, +}; + +static struct at91_twi_pdata at91sam9261_config = { + .clk_max_div = 5, + .clk_offset = 4, +}; + +static struct at91_twi_pdata at91sam9260_config = { + .clk_max_div = 7, + .clk_offset = 4, +}; + +static struct at91_twi_pdata at91sam9g20_config = { + .clk_max_div = 7, + .clk_offset = 4, +}; + +static struct at91_twi_pdata at91sam9g10_config = { + .clk_max_div = 7, + .clk_offset = 4, +}; + +static const struct platform_device_id at91_twi_devtypes[] = { + { + .name = "i2c-at91rm9200", + .driver_data = (unsigned long) &at91rm9200_config, + }, { + .name = "i2c-at91sam9261", + .driver_data = (unsigned long) &at91sam9261_config, + }, { + .name = "i2c-at91sam9260", + .driver_data = (unsigned long) &at91sam9260_config, + }, { + .name = "i2c-at91sam9g20", + .driver_data = (unsigned long) &at91sam9g20_config, + }, { + .name = "i2c-at91sam9g10", + .driver_data = (unsigned long) &at91sam9g10_config, + }, { + /* sentinel */ + } +}; + +#if defined(CONFIG_OF) +static struct at91_twi_pdata at91sam9x5_config = { + .clk_max_div = 7, + .clk_offset = 4, +}; + +static struct at91_twi_pdata sama5d4_config = { + .clk_max_div = 7, + .clk_offset = 4, + .has_hold_field = true, + .has_dig_filtr = true, +}; + +static struct at91_twi_pdata sama5d2_config = { + .clk_max_div = 7, + .clk_offset = 3, + .has_unre_flag = true, + .has_alt_cmd = true, + .has_hold_field = true, + .has_dig_filtr = true, + .has_adv_dig_filtr = true, + .has_ana_filtr = true, + .has_clear_cmd = false, /* due to errata, CLEAR cmd is not working */ +}; + +static struct at91_twi_pdata sam9x60_config = { + .clk_max_div = 7, + .clk_offset = 3, + .has_unre_flag = true, + .has_alt_cmd = true, + .has_hold_field = true, + .has_dig_filtr = true, + .has_adv_dig_filtr = true, + .has_ana_filtr = true, + .has_clear_cmd = true, +}; + +static const struct of_device_id atmel_twi_dt_ids[] = { + { + .compatible = "atmel,at91rm9200-i2c", + .data = &at91rm9200_config, + }, { + .compatible = "atmel,at91sam9260-i2c", + .data = &at91sam9260_config, + }, { + .compatible = "atmel,at91sam9261-i2c", + .data = &at91sam9261_config, + }, { + .compatible = "atmel,at91sam9g20-i2c", + .data = &at91sam9g20_config, + }, { + .compatible = "atmel,at91sam9g10-i2c", + .data = &at91sam9g10_config, + }, { + .compatible = "atmel,at91sam9x5-i2c", + .data = &at91sam9x5_config, + }, { + .compatible = "atmel,sama5d4-i2c", + .data = &sama5d4_config, + }, { + .compatible = "atmel,sama5d2-i2c", + .data = &sama5d2_config, + }, { + .compatible = "microchip,sam9x60-i2c", + .data = &sam9x60_config, + }, { + /* sentinel */ + } +}; +MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids); +#endif + +static struct at91_twi_pdata *at91_twi_get_driver_data( + struct platform_device *pdev) +{ + if (pdev->dev.of_node) { + const struct of_device_id *match; + match = of_match_node(atmel_twi_dt_ids, pdev->dev.of_node); + if (!match) + return NULL; + return (struct at91_twi_pdata *)match->data; + } + return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data; +} + +static int at91_twi_probe(struct platform_device *pdev) +{ + struct at91_twi_dev *dev; + struct resource *mem; + int rc; + u32 phy_addr; + + dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + + dev->dev = &pdev->dev; + + dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &mem); + if (IS_ERR(dev->base)) + return PTR_ERR(dev->base); + phy_addr = mem->start; + + dev->pdata = at91_twi_get_driver_data(pdev); + if (!dev->pdata) + return -ENODEV; + + dev->irq = platform_get_irq(pdev, 0); + if (dev->irq < 0) + return dev->irq; + + platform_set_drvdata(pdev, dev); + + dev->clk = devm_clk_get(dev->dev, NULL); + if (IS_ERR(dev->clk)) + return dev_err_probe(dev->dev, PTR_ERR(dev->clk), "no clock defined\n"); + + clk_prepare_enable(dev->clk); + + snprintf(dev->adapter.name, sizeof(dev->adapter.name), "AT91"); + i2c_set_adapdata(&dev->adapter, dev); + dev->adapter.owner = THIS_MODULE; + dev->adapter.class = I2C_CLASS_DEPRECATED; + dev->adapter.dev.parent = dev->dev; + dev->adapter.nr = pdev->id; + dev->adapter.timeout = AT91_I2C_TIMEOUT; + dev->adapter.dev.of_node = pdev->dev.of_node; + + dev->slave_detected = i2c_detect_slave_mode(&pdev->dev); + + if (dev->slave_detected) + rc = at91_twi_probe_slave(pdev, phy_addr, dev); + else + rc = at91_twi_probe_master(pdev, phy_addr, dev); + if (rc) + return rc; + + at91_init_twi_bus(dev); + + pm_runtime_set_autosuspend_delay(dev->dev, AUTOSUSPEND_TIMEOUT); + pm_runtime_use_autosuspend(dev->dev); + pm_runtime_set_active(dev->dev); + pm_runtime_enable(dev->dev); + + rc = i2c_add_numbered_adapter(&dev->adapter); + if (rc) { + clk_disable_unprepare(dev->clk); + + pm_runtime_disable(dev->dev); + pm_runtime_set_suspended(dev->dev); + + return rc; + } + + dev_info(dev->dev, "AT91 i2c bus driver (hw version: %#x).\n", + at91_twi_read(dev, AT91_TWI_VER)); + return 0; +} + +static void at91_twi_remove(struct platform_device *pdev) +{ + struct at91_twi_dev *dev = platform_get_drvdata(pdev); + + i2c_del_adapter(&dev->adapter); + clk_disable_unprepare(dev->clk); + + pm_runtime_disable(dev->dev); + pm_runtime_set_suspended(dev->dev); +} + +static int __maybe_unused at91_twi_runtime_suspend(struct device *dev) +{ + struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); + + clk_disable_unprepare(twi_dev->clk); + + pinctrl_pm_select_sleep_state(dev); + + return 0; +} + +static int __maybe_unused at91_twi_runtime_resume(struct device *dev) +{ + struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); + + pinctrl_pm_select_default_state(dev); + + return clk_prepare_enable(twi_dev->clk); +} + +static int __maybe_unused at91_twi_suspend_noirq(struct device *dev) +{ + if (!pm_runtime_status_suspended(dev)) + at91_twi_runtime_suspend(dev); + + return 0; +} + +static int __maybe_unused at91_twi_resume_noirq(struct device *dev) +{ + struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); + int ret; + + if (!pm_runtime_status_suspended(dev)) { + ret = at91_twi_runtime_resume(dev); + if (ret) + return ret; + } + + pm_runtime_mark_last_busy(dev); + pm_request_autosuspend(dev); + + at91_init_twi_bus(twi_dev); + + return 0; +} + +static const struct dev_pm_ops __maybe_unused at91_twi_pm = { + .suspend_noirq = at91_twi_suspend_noirq, + .resume_noirq = at91_twi_resume_noirq, + .runtime_suspend = at91_twi_runtime_suspend, + .runtime_resume = at91_twi_runtime_resume, +}; + +static struct platform_driver at91_twi_driver = { + .probe = at91_twi_probe, + .remove_new = at91_twi_remove, + .id_table = at91_twi_devtypes, + .driver = { + .name = "at91_i2c", + .of_match_table = of_match_ptr(atmel_twi_dt_ids), + .pm = pm_ptr(&at91_twi_pm), + }, +}; + +static int __init at91_twi_init(void) +{ + return platform_driver_register(&at91_twi_driver); +} + +static void __exit at91_twi_exit(void) +{ + platform_driver_unregister(&at91_twi_driver); +} + +subsys_initcall(at91_twi_init); +module_exit(at91_twi_exit); + +MODULE_AUTHOR("Nikolaus Voss <n.voss@weinmann.de>"); +MODULE_DESCRIPTION("I2C (TWI) driver for Atmel AT91"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:at91_i2c"); diff --git a/drivers/i2c/busses/i2c-at91-master.c b/drivers/i2c/busses/i2c-at91-master.c new file mode 100644 index 000000000..d311981d3 --- /dev/null +++ b/drivers/i2c/busses/i2c-at91-master.c @@ -0,0 +1,922 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * i2c Support for Atmel's AT91 Two-Wire Interface (TWI) + * + * Copyright (C) 2011 Weinmann Medical GmbH + * Author: Nikolaus Voss <n.voss@weinmann.de> + * + * Evolved from original work by: + * Copyright (C) 2004 Rick Bronson + * Converted to 2.6 by Andrew Victor <andrew@sanpeople.com> + * + * Borrowed heavily from original work by: + * Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com> + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/err.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> + +#include "i2c-at91.h" + +void at91_init_twi_bus_master(struct at91_twi_dev *dev) +{ + struct at91_twi_pdata *pdata = dev->pdata; + u32 filtr = 0; + + /* FIFO should be enabled immediately after the software reset */ + if (dev->fifo_size) + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_FIFOEN); + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_MSEN); + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SVDIS); + at91_twi_write(dev, AT91_TWI_CWGR, dev->twi_cwgr_reg); + + /* enable digital filter */ + if (pdata->has_dig_filtr && dev->enable_dig_filt) + filtr |= AT91_TWI_FILTR_FILT; + + /* enable advanced digital filter */ + if (pdata->has_adv_dig_filtr && dev->enable_dig_filt) + filtr |= AT91_TWI_FILTR_FILT | + (AT91_TWI_FILTR_THRES(dev->filter_width) & + AT91_TWI_FILTR_THRES_MASK); + + /* enable analog filter */ + if (pdata->has_ana_filtr && dev->enable_ana_filt) + filtr |= AT91_TWI_FILTR_PADFEN; + + if (filtr) + at91_twi_write(dev, AT91_TWI_FILTR, filtr); +} + +/* + * Calculate symmetric clock as stated in datasheet: + * twi_clk = F_MAIN / (2 * (cdiv * (1 << ckdiv) + offset)) + */ +static void at91_calc_twi_clock(struct at91_twi_dev *dev) +{ + int ckdiv, cdiv, div, hold = 0, filter_width = 0; + struct at91_twi_pdata *pdata = dev->pdata; + int offset = pdata->clk_offset; + int max_ckdiv = pdata->clk_max_div; + struct i2c_timings timings, *t = &timings; + + i2c_parse_fw_timings(dev->dev, t, true); + + div = max(0, (int)DIV_ROUND_UP(clk_get_rate(dev->clk), + 2 * t->bus_freq_hz) - offset); + ckdiv = fls(div >> 8); + cdiv = div >> ckdiv; + + if (ckdiv > max_ckdiv) { + dev_warn(dev->dev, "%d exceeds ckdiv max value which is %d.\n", + ckdiv, max_ckdiv); + ckdiv = max_ckdiv; + cdiv = 255; + } + + if (pdata->has_hold_field) { + /* + * hold time = HOLD + 3 x T_peripheral_clock + * Use clk rate in kHz to prevent overflows when computing + * hold. + */ + hold = DIV_ROUND_UP(t->sda_hold_ns + * (clk_get_rate(dev->clk) / 1000), 1000000); + hold -= 3; + if (hold < 0) + hold = 0; + if (hold > AT91_TWI_CWGR_HOLD_MAX) { + dev_warn(dev->dev, + "HOLD field set to its maximum value (%d instead of %d)\n", + AT91_TWI_CWGR_HOLD_MAX, hold); + hold = AT91_TWI_CWGR_HOLD_MAX; + } + } + + if (pdata->has_adv_dig_filtr) { + /* + * filter width = 0 to AT91_TWI_FILTR_THRES_MAX + * peripheral clocks + */ + filter_width = DIV_ROUND_UP(t->digital_filter_width_ns + * (clk_get_rate(dev->clk) / 1000), 1000000); + if (filter_width > AT91_TWI_FILTR_THRES_MAX) { + dev_warn(dev->dev, + "Filter threshold set to its maximum value (%d instead of %d)\n", + AT91_TWI_FILTR_THRES_MAX, filter_width); + filter_width = AT91_TWI_FILTR_THRES_MAX; + } + } + + dev->twi_cwgr_reg = (ckdiv << 16) | (cdiv << 8) | cdiv + | AT91_TWI_CWGR_HOLD(hold); + + dev->filter_width = filter_width; + + dev_dbg(dev->dev, "cdiv %d ckdiv %d hold %d (%d ns), filter_width %d (%d ns)\n", + cdiv, ckdiv, hold, t->sda_hold_ns, filter_width, + t->digital_filter_width_ns); +} + +static void at91_twi_dma_cleanup(struct at91_twi_dev *dev) +{ + struct at91_twi_dma *dma = &dev->dma; + + at91_twi_irq_save(dev); + + if (dma->xfer_in_progress) { + if (dma->direction == DMA_FROM_DEVICE) + dmaengine_terminate_sync(dma->chan_rx); + else + dmaengine_terminate_sync(dma->chan_tx); + dma->xfer_in_progress = false; + } + if (dma->buf_mapped) { + dma_unmap_single(dev->dev, sg_dma_address(&dma->sg[0]), + dev->buf_len, dma->direction); + dma->buf_mapped = false; + } + + at91_twi_irq_restore(dev); +} + +static void at91_twi_write_next_byte(struct at91_twi_dev *dev) +{ + if (!dev->buf_len) + return; + + /* 8bit write works with and without FIFO */ + writeb_relaxed(*dev->buf, dev->base + AT91_TWI_THR); + + /* send stop when last byte has been written */ + if (--dev->buf_len == 0) { + if (!dev->use_alt_cmd) + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_STOP); + at91_twi_write(dev, AT91_TWI_IDR, AT91_TWI_TXRDY); + } + + dev_dbg(dev->dev, "wrote 0x%x, to go %zu\n", *dev->buf, dev->buf_len); + + ++dev->buf; +} + +static void at91_twi_write_data_dma_callback(void *data) +{ + struct at91_twi_dev *dev = (struct at91_twi_dev *)data; + + dma_unmap_single(dev->dev, sg_dma_address(&dev->dma.sg[0]), + dev->buf_len, DMA_TO_DEVICE); + + /* + * When this callback is called, THR/TX FIFO is likely not to be empty + * yet. So we have to wait for TXCOMP or NACK bits to be set into the + * Status Register to be sure that the STOP bit has been sent and the + * transfer is completed. The NACK interrupt has already been enabled, + * we just have to enable TXCOMP one. + */ + at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_TXCOMP); + if (!dev->use_alt_cmd) + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_STOP); +} + +static void at91_twi_write_data_dma(struct at91_twi_dev *dev) +{ + dma_addr_t dma_addr; + struct dma_async_tx_descriptor *txdesc; + struct at91_twi_dma *dma = &dev->dma; + struct dma_chan *chan_tx = dma->chan_tx; + unsigned int sg_len = 1; + + if (!dev->buf_len) + return; + + dma->direction = DMA_TO_DEVICE; + + at91_twi_irq_save(dev); + dma_addr = dma_map_single(dev->dev, dev->buf, dev->buf_len, + DMA_TO_DEVICE); + if (dma_mapping_error(dev->dev, dma_addr)) { + dev_err(dev->dev, "dma map failed\n"); + return; + } + dma->buf_mapped = true; + at91_twi_irq_restore(dev); + + if (dev->fifo_size) { + size_t part1_len, part2_len; + struct scatterlist *sg; + unsigned fifo_mr; + + sg_len = 0; + + part1_len = dev->buf_len & ~0x3; + if (part1_len) { + sg = &dma->sg[sg_len++]; + sg_dma_len(sg) = part1_len; + sg_dma_address(sg) = dma_addr; + } + + part2_len = dev->buf_len & 0x3; + if (part2_len) { + sg = &dma->sg[sg_len++]; + sg_dma_len(sg) = part2_len; + sg_dma_address(sg) = dma_addr + part1_len; + } + + /* + * DMA controller is triggered when at least 4 data can be + * written into the TX FIFO + */ + fifo_mr = at91_twi_read(dev, AT91_TWI_FMR); + fifo_mr &= ~AT91_TWI_FMR_TXRDYM_MASK; + fifo_mr |= AT91_TWI_FMR_TXRDYM(AT91_TWI_FOUR_DATA); + at91_twi_write(dev, AT91_TWI_FMR, fifo_mr); + } else { + sg_dma_len(&dma->sg[0]) = dev->buf_len; + sg_dma_address(&dma->sg[0]) = dma_addr; + } + + txdesc = dmaengine_prep_slave_sg(chan_tx, dma->sg, sg_len, + DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!txdesc) { + dev_err(dev->dev, "dma prep slave sg failed\n"); + goto error; + } + + txdesc->callback = at91_twi_write_data_dma_callback; + txdesc->callback_param = dev; + + dma->xfer_in_progress = true; + dmaengine_submit(txdesc); + dma_async_issue_pending(chan_tx); + + return; + +error: + at91_twi_dma_cleanup(dev); +} + +static void at91_twi_read_next_byte(struct at91_twi_dev *dev) +{ + /* + * If we are in this case, it means there is garbage data in RHR, so + * delete them. + */ + if (!dev->buf_len) { + at91_twi_read(dev, AT91_TWI_RHR); + return; + } + + /* 8bit read works with and without FIFO */ + *dev->buf = readb_relaxed(dev->base + AT91_TWI_RHR); + --dev->buf_len; + + /* return if aborting, we only needed to read RHR to clear RXRDY*/ + if (dev->recv_len_abort) + return; + + /* handle I2C_SMBUS_BLOCK_DATA */ + if (unlikely(dev->msg->flags & I2C_M_RECV_LEN)) { + /* ensure length byte is a valid value */ + if (*dev->buf <= I2C_SMBUS_BLOCK_MAX && *dev->buf > 0) { + dev->msg->flags &= ~I2C_M_RECV_LEN; + dev->buf_len += *dev->buf; + dev->msg->len = dev->buf_len + 1; + dev_dbg(dev->dev, "received block length %zu\n", + dev->buf_len); + } else { + /* abort and send the stop by reading one more byte */ + dev->recv_len_abort = true; + dev->buf_len = 1; + } + } + + /* send stop if second but last byte has been read */ + if (!dev->use_alt_cmd && dev->buf_len == 1) + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_STOP); + + dev_dbg(dev->dev, "read 0x%x, to go %zu\n", *dev->buf, dev->buf_len); + + ++dev->buf; +} + +static void at91_twi_read_data_dma_callback(void *data) +{ + struct at91_twi_dev *dev = (struct at91_twi_dev *)data; + unsigned ier = AT91_TWI_TXCOMP; + + dma_unmap_single(dev->dev, sg_dma_address(&dev->dma.sg[0]), + dev->buf_len, DMA_FROM_DEVICE); + + if (!dev->use_alt_cmd) { + /* The last two bytes have to be read without using dma */ + dev->buf += dev->buf_len - 2; + dev->buf_len = 2; + ier |= AT91_TWI_RXRDY; + } + at91_twi_write(dev, AT91_TWI_IER, ier); +} + +static void at91_twi_read_data_dma(struct at91_twi_dev *dev) +{ + dma_addr_t dma_addr; + struct dma_async_tx_descriptor *rxdesc; + struct at91_twi_dma *dma = &dev->dma; + struct dma_chan *chan_rx = dma->chan_rx; + size_t buf_len; + + buf_len = (dev->use_alt_cmd) ? dev->buf_len : dev->buf_len - 2; + dma->direction = DMA_FROM_DEVICE; + + /* Keep in mind that we won't use dma to read the last two bytes */ + at91_twi_irq_save(dev); + dma_addr = dma_map_single(dev->dev, dev->buf, buf_len, DMA_FROM_DEVICE); + if (dma_mapping_error(dev->dev, dma_addr)) { + dev_err(dev->dev, "dma map failed\n"); + return; + } + dma->buf_mapped = true; + at91_twi_irq_restore(dev); + + if (dev->fifo_size && IS_ALIGNED(buf_len, 4)) { + unsigned fifo_mr; + + /* + * DMA controller is triggered when at least 4 data can be + * read from the RX FIFO + */ + fifo_mr = at91_twi_read(dev, AT91_TWI_FMR); + fifo_mr &= ~AT91_TWI_FMR_RXRDYM_MASK; + fifo_mr |= AT91_TWI_FMR_RXRDYM(AT91_TWI_FOUR_DATA); + at91_twi_write(dev, AT91_TWI_FMR, fifo_mr); + } + + sg_dma_len(&dma->sg[0]) = buf_len; + sg_dma_address(&dma->sg[0]) = dma_addr; + + rxdesc = dmaengine_prep_slave_sg(chan_rx, dma->sg, 1, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!rxdesc) { + dev_err(dev->dev, "dma prep slave sg failed\n"); + goto error; + } + + rxdesc->callback = at91_twi_read_data_dma_callback; + rxdesc->callback_param = dev; + + dma->xfer_in_progress = true; + dmaengine_submit(rxdesc); + dma_async_issue_pending(dma->chan_rx); + + return; + +error: + at91_twi_dma_cleanup(dev); +} + +static irqreturn_t atmel_twi_interrupt(int irq, void *dev_id) +{ + struct at91_twi_dev *dev = dev_id; + const unsigned status = at91_twi_read(dev, AT91_TWI_SR); + const unsigned irqstatus = status & at91_twi_read(dev, AT91_TWI_IMR); + + if (!irqstatus) + return IRQ_NONE; + /* + * In reception, the behavior of the twi device (before sama5d2) is + * weird. There is some magic about RXRDY flag! When a data has been + * almost received, the reception of a new one is anticipated if there + * is no stop command to send. That is the reason why ask for sending + * the stop command not on the last data but on the second last one. + * + * Unfortunately, we could still have the RXRDY flag set even if the + * transfer is done and we have read the last data. It might happen + * when the i2c slave device sends too quickly data after receiving the + * ack from the master. The data has been almost received before having + * the order to send stop. In this case, sending the stop command could + * cause a RXRDY interrupt with a TXCOMP one. It is better to manage + * the RXRDY interrupt first in order to not keep garbage data in the + * Receive Holding Register for the next transfer. + */ + if (irqstatus & AT91_TWI_RXRDY) { + /* + * Read all available bytes at once by polling RXRDY usable w/ + * and w/o FIFO. With FIFO enabled we could also read RXFL and + * avoid polling RXRDY. + */ + do { + at91_twi_read_next_byte(dev); + } while (at91_twi_read(dev, AT91_TWI_SR) & AT91_TWI_RXRDY); + } + + /* + * When a NACK condition is detected, the I2C controller sets the NACK, + * TXCOMP and TXRDY bits all together in the Status Register (SR). + * + * 1 - Handling NACK errors with CPU write transfer. + * + * In such case, we should not write the next byte into the Transmit + * Holding Register (THR) otherwise the I2C controller would start a new + * transfer and the I2C slave is likely to reply by another NACK. + * + * 2 - Handling NACK errors with DMA write transfer. + * + * By setting the TXRDY bit in the SR, the I2C controller also triggers + * the DMA controller to write the next data into the THR. Then the + * result depends on the hardware version of the I2C controller. + * + * 2a - Without support of the Alternative Command mode. + * + * This is the worst case: the DMA controller is triggered to write the + * next data into the THR, hence starting a new transfer: the I2C slave + * is likely to reply by another NACK. + * Concurrently, this interrupt handler is likely to be called to manage + * the first NACK before the I2C controller detects the second NACK and + * sets once again the NACK bit into the SR. + * When handling the first NACK, this interrupt handler disables the I2C + * controller interruptions, especially the NACK interrupt. + * Hence, the NACK bit is pending into the SR. This is why we should + * read the SR to clear all pending interrupts at the beginning of + * at91_do_twi_transfer() before actually starting a new transfer. + * + * 2b - With support of the Alternative Command mode. + * + * When a NACK condition is detected, the I2C controller also locks the + * THR (and sets the LOCK bit in the SR): even though the DMA controller + * is triggered by the TXRDY bit to write the next data into the THR, + * this data actually won't go on the I2C bus hence a second NACK is not + * generated. + */ + if (irqstatus & (AT91_TWI_TXCOMP | AT91_TWI_NACK)) { + at91_disable_twi_interrupts(dev); + complete(&dev->cmd_complete); + } else if (irqstatus & AT91_TWI_TXRDY) { + at91_twi_write_next_byte(dev); + } + + /* catch error flags */ + dev->transfer_status |= status; + + return IRQ_HANDLED; +} + +static int at91_do_twi_transfer(struct at91_twi_dev *dev) +{ + int ret; + unsigned long time_left; + bool has_unre_flag = dev->pdata->has_unre_flag; + bool has_alt_cmd = dev->pdata->has_alt_cmd; + + /* + * WARNING: the TXCOMP bit in the Status Register is NOT a clear on + * read flag but shows the state of the transmission at the time the + * Status Register is read. According to the programmer datasheet, + * TXCOMP is set when both holding register and internal shifter are + * empty and STOP condition has been sent. + * Consequently, we should enable NACK interrupt rather than TXCOMP to + * detect transmission failure. + * Indeed let's take the case of an i2c write command using DMA. + * Whenever the slave doesn't acknowledge a byte, the LOCK, NACK and + * TXCOMP bits are set together into the Status Register. + * LOCK is a clear on write bit, which is set to prevent the DMA + * controller from sending new data on the i2c bus after a NACK + * condition has happened. Once locked, this i2c peripheral stops + * triggering the DMA controller for new data but it is more than + * likely that a new DMA transaction is already in progress, writing + * into the Transmit Holding Register. Since the peripheral is locked, + * these new data won't be sent to the i2c bus but they will remain + * into the Transmit Holding Register, so TXCOMP bit is cleared. + * Then when the interrupt handler is called, the Status Register is + * read: the TXCOMP bit is clear but NACK bit is still set. The driver + * manage the error properly, without waiting for timeout. + * This case can be reproduced easyly when writing into an at24 eeprom. + * + * Besides, the TXCOMP bit is already set before the i2c transaction + * has been started. For read transactions, this bit is cleared when + * writing the START bit into the Control Register. So the + * corresponding interrupt can safely be enabled just after. + * However for write transactions managed by the CPU, we first write + * into THR, so TXCOMP is cleared. Then we can safely enable TXCOMP + * interrupt. If TXCOMP interrupt were enabled before writing into THR, + * the interrupt handler would be called immediately and the i2c command + * would be reported as completed. + * Also when a write transaction is managed by the DMA controller, + * enabling the TXCOMP interrupt in this function may lead to a race + * condition since we don't know whether the TXCOMP interrupt is enabled + * before or after the DMA has started to write into THR. So the TXCOMP + * interrupt is enabled later by at91_twi_write_data_dma_callback(). + * Immediately after in that DMA callback, if the alternative command + * mode is not used, we still need to send the STOP condition manually + * writing the corresponding bit into the Control Register. + */ + + dev_dbg(dev->dev, "transfer: %s %zu bytes.\n", + (dev->msg->flags & I2C_M_RD) ? "read" : "write", dev->buf_len); + + reinit_completion(&dev->cmd_complete); + dev->transfer_status = 0; + + /* Clear pending interrupts, such as NACK. */ + at91_twi_read(dev, AT91_TWI_SR); + + if (dev->fifo_size) { + unsigned fifo_mr = at91_twi_read(dev, AT91_TWI_FMR); + + /* Reset FIFO mode register */ + fifo_mr &= ~(AT91_TWI_FMR_TXRDYM_MASK | + AT91_TWI_FMR_RXRDYM_MASK); + fifo_mr |= AT91_TWI_FMR_TXRDYM(AT91_TWI_ONE_DATA); + fifo_mr |= AT91_TWI_FMR_RXRDYM(AT91_TWI_ONE_DATA); + at91_twi_write(dev, AT91_TWI_FMR, fifo_mr); + + /* Flush FIFOs */ + at91_twi_write(dev, AT91_TWI_CR, + AT91_TWI_THRCLR | AT91_TWI_RHRCLR); + } + + if (!dev->buf_len) { + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_QUICK); + at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_TXCOMP); + } else if (dev->msg->flags & I2C_M_RD) { + unsigned start_flags = AT91_TWI_START; + + /* if only one byte is to be read, immediately stop transfer */ + if (!dev->use_alt_cmd && dev->buf_len <= 1 && + !(dev->msg->flags & I2C_M_RECV_LEN)) + start_flags |= AT91_TWI_STOP; + at91_twi_write(dev, AT91_TWI_CR, start_flags); + /* + * When using dma without alternative command mode, the last + * byte has to be read manually in order to not send the stop + * command too late and then to receive extra data. + * In practice, there are some issues if you use the dma to + * read n-1 bytes because of latency. + * Reading n-2 bytes with dma and the two last ones manually + * seems to be the best solution. + */ + if (dev->use_dma && (dev->buf_len > AT91_I2C_DMA_THRESHOLD)) { + at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_NACK); + at91_twi_read_data_dma(dev); + } else { + at91_twi_write(dev, AT91_TWI_IER, + AT91_TWI_TXCOMP | + AT91_TWI_NACK | + AT91_TWI_RXRDY); + } + } else { + if (dev->use_dma && (dev->buf_len > AT91_I2C_DMA_THRESHOLD)) { + at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_NACK); + at91_twi_write_data_dma(dev); + } else { + at91_twi_write_next_byte(dev); + at91_twi_write(dev, AT91_TWI_IER, + AT91_TWI_TXCOMP | AT91_TWI_NACK | + (dev->buf_len ? AT91_TWI_TXRDY : 0)); + } + } + + time_left = wait_for_completion_timeout(&dev->cmd_complete, + dev->adapter.timeout); + if (time_left == 0) { + dev->transfer_status |= at91_twi_read(dev, AT91_TWI_SR); + dev_err(dev->dev, "controller timed out\n"); + at91_init_twi_bus(dev); + ret = -ETIMEDOUT; + goto error; + } + if (dev->transfer_status & AT91_TWI_NACK) { + dev_dbg(dev->dev, "received nack\n"); + ret = -EREMOTEIO; + goto error; + } + if (dev->transfer_status & AT91_TWI_OVRE) { + dev_err(dev->dev, "overrun while reading\n"); + ret = -EIO; + goto error; + } + if (has_unre_flag && dev->transfer_status & AT91_TWI_UNRE) { + dev_err(dev->dev, "underrun while writing\n"); + ret = -EIO; + goto error; + } + if ((has_alt_cmd || dev->fifo_size) && + (dev->transfer_status & AT91_TWI_LOCK)) { + dev_err(dev->dev, "tx locked\n"); + ret = -EIO; + goto error; + } + if (dev->recv_len_abort) { + dev_err(dev->dev, "invalid smbus block length recvd\n"); + ret = -EPROTO; + goto error; + } + + dev_dbg(dev->dev, "transfer complete\n"); + + return 0; + +error: + /* first stop DMA transfer if still in progress */ + at91_twi_dma_cleanup(dev); + /* then flush THR/FIFO and unlock TX if locked */ + if ((has_alt_cmd || dev->fifo_size) && + (dev->transfer_status & AT91_TWI_LOCK)) { + dev_dbg(dev->dev, "unlock tx\n"); + at91_twi_write(dev, AT91_TWI_CR, + AT91_TWI_THRCLR | AT91_TWI_LOCKCLR); + } + + /* + * some faulty I2C slave devices might hold SDA down; + * we can send a bus clear command, hoping that the pins will be + * released + */ + i2c_recover_bus(&dev->adapter); + + return ret; +} + +static int at91_twi_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, int num) +{ + struct at91_twi_dev *dev = i2c_get_adapdata(adap); + int ret; + unsigned int_addr_flag = 0; + struct i2c_msg *m_start = msg; + bool is_read; + u8 *dma_buf = NULL; + + dev_dbg(&adap->dev, "at91_xfer: processing %d messages:\n", num); + + ret = pm_runtime_get_sync(dev->dev); + if (ret < 0) + goto out; + + if (num == 2) { + int internal_address = 0; + int i; + + /* 1st msg is put into the internal address, start with 2nd */ + m_start = &msg[1]; + for (i = 0; i < msg->len; ++i) { + const unsigned addr = msg->buf[msg->len - 1 - i]; + + internal_address |= addr << (8 * i); + int_addr_flag += AT91_TWI_IADRSZ_1; + } + at91_twi_write(dev, AT91_TWI_IADR, internal_address); + } + + dev->use_alt_cmd = false; + is_read = (m_start->flags & I2C_M_RD); + if (dev->pdata->has_alt_cmd) { + if (m_start->len > 0 && + m_start->len < AT91_I2C_MAX_ALT_CMD_DATA_SIZE) { + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_ACMEN); + at91_twi_write(dev, AT91_TWI_ACR, + AT91_TWI_ACR_DATAL(m_start->len) | + ((is_read) ? AT91_TWI_ACR_DIR : 0)); + dev->use_alt_cmd = true; + } else { + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_ACMDIS); + } + } + + at91_twi_write(dev, AT91_TWI_MMR, + (m_start->addr << 16) | + int_addr_flag | + ((!dev->use_alt_cmd && is_read) ? AT91_TWI_MREAD : 0)); + + dev->buf_len = m_start->len; + dev->buf = m_start->buf; + dev->msg = m_start; + dev->recv_len_abort = false; + + if (dev->use_dma) { + dma_buf = i2c_get_dma_safe_msg_buf(m_start, 1); + if (!dma_buf) { + ret = -ENOMEM; + goto out; + } + dev->buf = dma_buf; + } + + ret = at91_do_twi_transfer(dev); + i2c_put_dma_safe_msg_buf(dma_buf, m_start, !ret); + + ret = (ret < 0) ? ret : num; +out: + pm_runtime_mark_last_busy(dev->dev); + pm_runtime_put_autosuspend(dev->dev); + + return ret; +} + +/* + * The hardware can handle at most two messages concatenated by a + * repeated start via it's internal address feature. + */ +static const struct i2c_adapter_quirks at91_twi_quirks = { + .flags = I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | I2C_AQ_COMB_SAME_ADDR, + .max_comb_1st_msg_len = 3, +}; + +static u32 at91_twi_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL + | I2C_FUNC_SMBUS_READ_BLOCK_DATA; +} + +static const struct i2c_algorithm at91_twi_algorithm = { + .master_xfer = at91_twi_xfer, + .functionality = at91_twi_func, +}; + +static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr) +{ + int ret = 0; + struct dma_slave_config slave_config; + struct at91_twi_dma *dma = &dev->dma; + enum dma_slave_buswidth addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + + /* + * The actual width of the access will be chosen in + * dmaengine_prep_slave_sg(): + * for each buffer in the scatter-gather list, if its size is aligned + * to addr_width then addr_width accesses will be performed to transfer + * the buffer. On the other hand, if the buffer size is not aligned to + * addr_width then the buffer is transferred using single byte accesses. + * Please refer to the Atmel eXtended DMA controller driver. + * When FIFOs are used, the TXRDYM threshold can always be set to + * trigger the XDMAC when at least 4 data can be written into the TX + * FIFO, even if single byte accesses are performed. + * However the RXRDYM threshold must be set to fit the access width, + * deduced from buffer length, so the XDMAC is triggered properly to + * read data from the RX FIFO. + */ + if (dev->fifo_size) + addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + + memset(&slave_config, 0, sizeof(slave_config)); + slave_config.src_addr = (dma_addr_t)phy_addr + AT91_TWI_RHR; + slave_config.src_addr_width = addr_width; + slave_config.src_maxburst = 1; + slave_config.dst_addr = (dma_addr_t)phy_addr + AT91_TWI_THR; + slave_config.dst_addr_width = addr_width; + slave_config.dst_maxburst = 1; + slave_config.device_fc = false; + + dma->chan_tx = dma_request_chan(dev->dev, "tx"); + if (IS_ERR(dma->chan_tx)) { + ret = PTR_ERR(dma->chan_tx); + dma->chan_tx = NULL; + goto error; + } + + dma->chan_rx = dma_request_chan(dev->dev, "rx"); + if (IS_ERR(dma->chan_rx)) { + ret = PTR_ERR(dma->chan_rx); + dma->chan_rx = NULL; + goto error; + } + + slave_config.direction = DMA_MEM_TO_DEV; + if (dmaengine_slave_config(dma->chan_tx, &slave_config)) { + dev_err(dev->dev, "failed to configure tx channel\n"); + ret = -EINVAL; + goto error; + } + + slave_config.direction = DMA_DEV_TO_MEM; + if (dmaengine_slave_config(dma->chan_rx, &slave_config)) { + dev_err(dev->dev, "failed to configure rx channel\n"); + ret = -EINVAL; + goto error; + } + + sg_init_table(dma->sg, 2); + dma->buf_mapped = false; + dma->xfer_in_progress = false; + dev->use_dma = true; + + dev_info(dev->dev, "using %s (tx) and %s (rx) for DMA transfers\n", + dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx)); + + return ret; + +error: + if (ret != -EPROBE_DEFER) + dev_info(dev->dev, "can't get DMA channel, continue without DMA support\n"); + if (dma->chan_rx) + dma_release_channel(dma->chan_rx); + if (dma->chan_tx) + dma_release_channel(dma->chan_tx); + return ret; +} + +static int at91_init_twi_recovery_gpio(struct platform_device *pdev, + struct at91_twi_dev *dev) +{ + struct i2c_bus_recovery_info *rinfo = &dev->rinfo; + + rinfo->pinctrl = devm_pinctrl_get(&pdev->dev); + if (!rinfo->pinctrl) { + dev_info(dev->dev, "pinctrl unavailable, bus recovery not supported\n"); + return 0; + } + if (IS_ERR(rinfo->pinctrl)) { + dev_info(dev->dev, "can't get pinctrl, bus recovery not supported\n"); + return PTR_ERR(rinfo->pinctrl); + } + dev->adapter.bus_recovery_info = rinfo; + + return 0; +} + +static int at91_twi_recover_bus_cmd(struct i2c_adapter *adap) +{ + struct at91_twi_dev *dev = i2c_get_adapdata(adap); + + dev->transfer_status |= at91_twi_read(dev, AT91_TWI_SR); + if (!(dev->transfer_status & AT91_TWI_SDA)) { + dev_dbg(dev->dev, "SDA is down; sending bus clear command\n"); + if (dev->use_alt_cmd) { + unsigned int acr; + + acr = at91_twi_read(dev, AT91_TWI_ACR); + acr &= ~AT91_TWI_ACR_DATAL_MASK; + at91_twi_write(dev, AT91_TWI_ACR, acr); + } + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_CLEAR); + } + + return 0; +} + +static int at91_init_twi_recovery_info(struct platform_device *pdev, + struct at91_twi_dev *dev) +{ + struct i2c_bus_recovery_info *rinfo = &dev->rinfo; + bool has_clear_cmd = dev->pdata->has_clear_cmd; + + if (!has_clear_cmd) + return at91_init_twi_recovery_gpio(pdev, dev); + + rinfo->recover_bus = at91_twi_recover_bus_cmd; + dev->adapter.bus_recovery_info = rinfo; + + return 0; +} + +int at91_twi_probe_master(struct platform_device *pdev, + u32 phy_addr, struct at91_twi_dev *dev) +{ + int rc; + + init_completion(&dev->cmd_complete); + + rc = devm_request_irq(&pdev->dev, dev->irq, atmel_twi_interrupt, 0, + dev_name(dev->dev), dev); + if (rc) { + dev_err(dev->dev, "Cannot get irq %d: %d\n", dev->irq, rc); + return rc; + } + + if (dev->dev->of_node) { + rc = at91_twi_configure_dma(dev, phy_addr); + if (rc == -EPROBE_DEFER) + return rc; + } + + if (!of_property_read_u32(pdev->dev.of_node, "atmel,fifo-size", + &dev->fifo_size)) { + dev_info(dev->dev, "Using FIFO (%u data)\n", dev->fifo_size); + } + + dev->enable_dig_filt = of_property_read_bool(pdev->dev.of_node, + "i2c-digital-filter"); + + dev->enable_ana_filt = of_property_read_bool(pdev->dev.of_node, + "i2c-analog-filter"); + at91_calc_twi_clock(dev); + + rc = at91_init_twi_recovery_info(pdev, dev); + if (rc == -EPROBE_DEFER) + return rc; + + dev->adapter.algo = &at91_twi_algorithm; + dev->adapter.quirks = &at91_twi_quirks; + + return 0; +} diff --git a/drivers/i2c/busses/i2c-at91-slave.c b/drivers/i2c/busses/i2c-at91-slave.c new file mode 100644 index 000000000..d6eeea516 --- /dev/null +++ b/drivers/i2c/busses/i2c-at91-slave.c @@ -0,0 +1,143 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * i2c slave support for Atmel's AT91 Two-Wire Interface (TWI) + * + * Copyright (C) 2017 Juergen Fitschen <me@jue.yt> + */ + +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/pm_runtime.h> + +#include "i2c-at91.h" + +static irqreturn_t atmel_twi_interrupt_slave(int irq, void *dev_id) +{ + struct at91_twi_dev *dev = dev_id; + const unsigned status = at91_twi_read(dev, AT91_TWI_SR); + const unsigned irqstatus = status & at91_twi_read(dev, AT91_TWI_IMR); + u8 value; + + if (!irqstatus) + return IRQ_NONE; + + /* slave address has been detected on I2C bus */ + if (irqstatus & AT91_TWI_SVACC) { + if (status & AT91_TWI_SVREAD) { + i2c_slave_event(dev->slave, + I2C_SLAVE_READ_REQUESTED, &value); + writeb_relaxed(value, dev->base + AT91_TWI_THR); + at91_twi_write(dev, AT91_TWI_IER, + AT91_TWI_TXRDY | AT91_TWI_EOSACC); + } else { + i2c_slave_event(dev->slave, + I2C_SLAVE_WRITE_REQUESTED, &value); + at91_twi_write(dev, AT91_TWI_IER, + AT91_TWI_RXRDY | AT91_TWI_EOSACC); + } + at91_twi_write(dev, AT91_TWI_IDR, AT91_TWI_SVACC); + } + + /* byte transmitted to remote master */ + if (irqstatus & AT91_TWI_TXRDY) { + i2c_slave_event(dev->slave, I2C_SLAVE_READ_PROCESSED, &value); + writeb_relaxed(value, dev->base + AT91_TWI_THR); + } + + /* byte received from remote master */ + if (irqstatus & AT91_TWI_RXRDY) { + value = readb_relaxed(dev->base + AT91_TWI_RHR); + i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_RECEIVED, &value); + } + + /* master sent stop */ + if (irqstatus & AT91_TWI_EOSACC) { + at91_twi_write(dev, AT91_TWI_IDR, + AT91_TWI_TXRDY | AT91_TWI_RXRDY | AT91_TWI_EOSACC); + at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_SVACC); + i2c_slave_event(dev->slave, I2C_SLAVE_STOP, &value); + } + + return IRQ_HANDLED; +} + +static int at91_reg_slave(struct i2c_client *slave) +{ + struct at91_twi_dev *dev = i2c_get_adapdata(slave->adapter); + + if (dev->slave) + return -EBUSY; + + if (slave->flags & I2C_CLIENT_TEN) + return -EAFNOSUPPORT; + + /* Make sure twi_clk doesn't get turned off! */ + pm_runtime_get_sync(dev->dev); + + dev->slave = slave; + dev->smr = AT91_TWI_SMR_SADR(slave->addr); + + at91_init_twi_bus(dev); + at91_twi_write(dev, AT91_TWI_IER, AT91_TWI_SVACC); + + dev_info(dev->dev, "entered slave mode (ADR=%d)\n", slave->addr); + + return 0; +} + +static int at91_unreg_slave(struct i2c_client *slave) +{ + struct at91_twi_dev *dev = i2c_get_adapdata(slave->adapter); + + WARN_ON(!dev->slave); + + dev_info(dev->dev, "leaving slave mode\n"); + + dev->slave = NULL; + dev->smr = 0; + + at91_init_twi_bus(dev); + + pm_runtime_put(dev->dev); + + return 0; +} + +static u32 at91_twi_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SLAVE | I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL + | I2C_FUNC_SMBUS_READ_BLOCK_DATA; +} + +static const struct i2c_algorithm at91_twi_algorithm_slave = { + .reg_slave = at91_reg_slave, + .unreg_slave = at91_unreg_slave, + .functionality = at91_twi_func, +}; + +int at91_twi_probe_slave(struct platform_device *pdev, + u32 phy_addr, struct at91_twi_dev *dev) +{ + int rc; + + rc = devm_request_irq(&pdev->dev, dev->irq, atmel_twi_interrupt_slave, + 0, dev_name(dev->dev), dev); + if (rc) { + dev_err(dev->dev, "Cannot get irq %d: %d\n", dev->irq, rc); + return rc; + } + + dev->adapter.algo = &at91_twi_algorithm_slave; + + return 0; +} + +void at91_init_twi_bus_slave(struct at91_twi_dev *dev) +{ + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_MSDIS); + if (dev->slave_detected && dev->smr) { + at91_twi_write(dev, AT91_TWI_SMR, dev->smr); + at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SVEN); + } +} diff --git a/drivers/i2c/busses/i2c-at91.h b/drivers/i2c/busses/i2c-at91.h new file mode 100644 index 000000000..942e9c397 --- /dev/null +++ b/drivers/i2c/busses/i2c-at91.h @@ -0,0 +1,191 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * i2c Support for Atmel's AT91 Two-Wire Interface (TWI) + * + * Copyright (C) 2011 Weinmann Medical GmbH + * Author: Nikolaus Voss <n.voss@weinmann.de> + * + * Evolved from original work by: + * Copyright (C) 2004 Rick Bronson + * Converted to 2.6 by Andrew Victor <andrew@sanpeople.com> + * + * Borrowed heavily from original work by: + * Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com> + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/i2c.h> +#include <linux/platform_device.h> + +#define AT91_I2C_TIMEOUT msecs_to_jiffies(100) /* transfer timeout */ +#define AT91_I2C_DMA_THRESHOLD 8 /* enable DMA if transfer size is bigger than this threshold */ +#define AUTOSUSPEND_TIMEOUT 2000 +#define AT91_I2C_MAX_ALT_CMD_DATA_SIZE 256 + +/* AT91 TWI register definitions */ +#define AT91_TWI_CR 0x0000 /* Control Register */ +#define AT91_TWI_START BIT(0) /* Send a Start Condition */ +#define AT91_TWI_STOP BIT(1) /* Send a Stop Condition */ +#define AT91_TWI_MSEN BIT(2) /* Master Transfer Enable */ +#define AT91_TWI_MSDIS BIT(3) /* Master Transfer Disable */ +#define AT91_TWI_SVEN BIT(4) /* Slave Transfer Enable */ +#define AT91_TWI_SVDIS BIT(5) /* Slave Transfer Disable */ +#define AT91_TWI_QUICK BIT(6) /* SMBus quick command */ +#define AT91_TWI_SWRST BIT(7) /* Software Reset */ +#define AT91_TWI_CLEAR BIT(15) /* Bus clear command */ +#define AT91_TWI_ACMEN BIT(16) /* Alternative Command Mode Enable */ +#define AT91_TWI_ACMDIS BIT(17) /* Alternative Command Mode Disable */ +#define AT91_TWI_THRCLR BIT(24) /* Transmit Holding Register Clear */ +#define AT91_TWI_RHRCLR BIT(25) /* Receive Holding Register Clear */ +#define AT91_TWI_LOCKCLR BIT(26) /* Lock Clear */ +#define AT91_TWI_FIFOEN BIT(28) /* FIFO Enable */ +#define AT91_TWI_FIFODIS BIT(29) /* FIFO Disable */ + +#define AT91_TWI_MMR 0x0004 /* Master Mode Register */ +#define AT91_TWI_IADRSZ_1 0x0100 /* Internal Device Address Size */ +#define AT91_TWI_MREAD BIT(12) /* Master Read Direction */ + +#define AT91_TWI_SMR 0x0008 /* Slave Mode Register */ +#define AT91_TWI_SMR_SADR_MAX 0x007f +#define AT91_TWI_SMR_SADR(x) (((x) & AT91_TWI_SMR_SADR_MAX) << 16) + +#define AT91_TWI_IADR 0x000c /* Internal Address Register */ + +#define AT91_TWI_CWGR 0x0010 /* Clock Waveform Generator Reg */ +#define AT91_TWI_CWGR_HOLD_MAX 0x1f +#define AT91_TWI_CWGR_HOLD(x) (((x) & AT91_TWI_CWGR_HOLD_MAX) << 24) + +#define AT91_TWI_SR 0x0020 /* Status Register */ +#define AT91_TWI_TXCOMP BIT(0) /* Transmission Complete */ +#define AT91_TWI_RXRDY BIT(1) /* Receive Holding Register Ready */ +#define AT91_TWI_TXRDY BIT(2) /* Transmit Holding Register Ready */ +#define AT91_TWI_SVREAD BIT(3) /* Slave Read */ +#define AT91_TWI_SVACC BIT(4) /* Slave Access */ +#define AT91_TWI_OVRE BIT(6) /* Overrun Error */ +#define AT91_TWI_UNRE BIT(7) /* Underrun Error */ +#define AT91_TWI_NACK BIT(8) /* Not Acknowledged */ +#define AT91_TWI_EOSACC BIT(11) /* End Of Slave Access */ +#define AT91_TWI_LOCK BIT(23) /* TWI Lock due to Frame Errors */ +#define AT91_TWI_SCL BIT(24) /* TWI SCL status */ +#define AT91_TWI_SDA BIT(25) /* TWI SDA status */ + +#define AT91_TWI_INT_MASK \ + (AT91_TWI_TXCOMP | AT91_TWI_RXRDY | AT91_TWI_TXRDY | AT91_TWI_NACK \ + | AT91_TWI_SVACC | AT91_TWI_EOSACC) + +#define AT91_TWI_IER 0x0024 /* Interrupt Enable Register */ +#define AT91_TWI_IDR 0x0028 /* Interrupt Disable Register */ +#define AT91_TWI_IMR 0x002c /* Interrupt Mask Register */ +#define AT91_TWI_RHR 0x0030 /* Receive Holding Register */ +#define AT91_TWI_THR 0x0034 /* Transmit Holding Register */ + +#define AT91_TWI_ACR 0x0040 /* Alternative Command Register */ +#define AT91_TWI_ACR_DATAL_MASK GENMASK(15, 0) +#define AT91_TWI_ACR_DATAL(len) ((len) & AT91_TWI_ACR_DATAL_MASK) +#define AT91_TWI_ACR_DIR BIT(8) + +#define AT91_TWI_FILTR 0x0044 +#define AT91_TWI_FILTR_FILT BIT(0) +#define AT91_TWI_FILTR_PADFEN BIT(1) +#define AT91_TWI_FILTR_THRES(v) ((v) << 8) +#define AT91_TWI_FILTR_THRES_MAX 7 +#define AT91_TWI_FILTR_THRES_MASK GENMASK(10, 8) + +#define AT91_TWI_FMR 0x0050 /* FIFO Mode Register */ +#define AT91_TWI_FMR_TXRDYM(mode) (((mode) & 0x3) << 0) +#define AT91_TWI_FMR_TXRDYM_MASK (0x3 << 0) +#define AT91_TWI_FMR_RXRDYM(mode) (((mode) & 0x3) << 4) +#define AT91_TWI_FMR_RXRDYM_MASK (0x3 << 4) +#define AT91_TWI_ONE_DATA 0x0 +#define AT91_TWI_TWO_DATA 0x1 +#define AT91_TWI_FOUR_DATA 0x2 + +#define AT91_TWI_FLR 0x0054 /* FIFO Level Register */ + +#define AT91_TWI_FSR 0x0060 /* FIFO Status Register */ +#define AT91_TWI_FIER 0x0064 /* FIFO Interrupt Enable Register */ +#define AT91_TWI_FIDR 0x0068 /* FIFO Interrupt Disable Register */ +#define AT91_TWI_FIMR 0x006c /* FIFO Interrupt Mask Register */ + +#define AT91_TWI_VER 0x00fc /* Version Register */ + +struct at91_twi_pdata { + unsigned clk_max_div; + unsigned clk_offset; + bool has_unre_flag; + bool has_alt_cmd; + bool has_hold_field; + bool has_dig_filtr; + bool has_adv_dig_filtr; + bool has_ana_filtr; + bool has_clear_cmd; +}; + +struct at91_twi_dma { + struct dma_chan *chan_rx; + struct dma_chan *chan_tx; + struct scatterlist sg[2]; + struct dma_async_tx_descriptor *data_desc; + enum dma_data_direction direction; + bool buf_mapped; + bool xfer_in_progress; +}; + +struct at91_twi_dev { + struct device *dev; + void __iomem *base; + struct completion cmd_complete; + struct clk *clk; + u8 *buf; + size_t buf_len; + struct i2c_msg *msg; + int irq; + unsigned imr; + unsigned transfer_status; + struct i2c_adapter adapter; + unsigned twi_cwgr_reg; + struct at91_twi_pdata *pdata; + bool use_dma; + bool use_alt_cmd; + bool recv_len_abort; + u32 fifo_size; + struct at91_twi_dma dma; + bool slave_detected; + struct i2c_bus_recovery_info rinfo; +#ifdef CONFIG_I2C_AT91_SLAVE_EXPERIMENTAL + unsigned smr; + struct i2c_client *slave; +#endif + bool enable_dig_filt; + bool enable_ana_filt; + u32 filter_width; +}; + +unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg); +void at91_twi_write(struct at91_twi_dev *dev, unsigned reg, unsigned val); +void at91_disable_twi_interrupts(struct at91_twi_dev *dev); +void at91_twi_irq_save(struct at91_twi_dev *dev); +void at91_twi_irq_restore(struct at91_twi_dev *dev); +void at91_init_twi_bus(struct at91_twi_dev *dev); + +void at91_init_twi_bus_master(struct at91_twi_dev *dev); +int at91_twi_probe_master(struct platform_device *pdev, u32 phy_addr, + struct at91_twi_dev *dev); + +#ifdef CONFIG_I2C_AT91_SLAVE_EXPERIMENTAL +void at91_init_twi_bus_slave(struct at91_twi_dev *dev); +int at91_twi_probe_slave(struct platform_device *pdev, u32 phy_addr, + struct at91_twi_dev *dev); + +#else +static inline void at91_init_twi_bus_slave(struct at91_twi_dev *dev) {} +static inline int at91_twi_probe_slave(struct platform_device *pdev, + u32 phy_addr, struct at91_twi_dev *dev) +{ + return -EINVAL; +} + +#endif diff --git a/drivers/i2c/busses/i2c-au1550.c b/drivers/i2c/busses/i2c-au1550.c new file mode 100644 index 000000000..8e43f25c1 --- /dev/null +++ b/drivers/i2c/busses/i2c-au1550.c @@ -0,0 +1,380 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * i2c-au1550.c: SMBus (i2c) adapter for Alchemy PSC interface + * Copyright (C) 2004 Embedded Edge, LLC <dan@embeddededge.com> + * + * 2.6 port by Matt Porter <mporter@kernel.crashing.org> + * + * The documentation describes this as an SMBus controller, but it doesn't + * understand any of the SMBus protocol in hardware. It's really an I2C + * controller that could emulate most of the SMBus in software. + * + * This is just a skeleton adapter to use with the Au1550 PSC + * algorithm. It was developed for the Pb1550, but will work with + * any Au1550 board that has a similar PSC configuration. + */ + +#include <linux/delay.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/slab.h> + +#include <asm/mach-au1x00/au1000.h> +#include <asm/mach-au1x00/au1xxx_psc.h> + +#define PSC_SEL 0x00 +#define PSC_CTRL 0x04 +#define PSC_SMBCFG 0x08 +#define PSC_SMBMSK 0x0C +#define PSC_SMBPCR 0x10 +#define PSC_SMBSTAT 0x14 +#define PSC_SMBEVNT 0x18 +#define PSC_SMBTXRX 0x1C +#define PSC_SMBTMR 0x20 + +struct i2c_au1550_data { + void __iomem *psc_base; + int xfer_timeout; + struct i2c_adapter adap; +}; + +static inline void WR(struct i2c_au1550_data *a, int r, unsigned long v) +{ + __raw_writel(v, a->psc_base + r); + wmb(); +} + +static inline unsigned long RD(struct i2c_au1550_data *a, int r) +{ + return __raw_readl(a->psc_base + r); +} + +static int wait_xfer_done(struct i2c_au1550_data *adap) +{ + int i; + + /* Wait for Tx Buffer Empty */ + for (i = 0; i < adap->xfer_timeout; i++) { + if (RD(adap, PSC_SMBSTAT) & PSC_SMBSTAT_TE) + return 0; + + udelay(1); + } + + return -ETIMEDOUT; +} + +static int wait_ack(struct i2c_au1550_data *adap) +{ + unsigned long stat; + + if (wait_xfer_done(adap)) + return -ETIMEDOUT; + + stat = RD(adap, PSC_SMBEVNT); + if ((stat & (PSC_SMBEVNT_DN | PSC_SMBEVNT_AN | PSC_SMBEVNT_AL)) != 0) + return -ETIMEDOUT; + + return 0; +} + +static int wait_master_done(struct i2c_au1550_data *adap) +{ + int i; + + /* Wait for Master Done. */ + for (i = 0; i < 2 * adap->xfer_timeout; i++) { + if ((RD(adap, PSC_SMBEVNT) & PSC_SMBEVNT_MD) != 0) + return 0; + udelay(1); + } + + return -ETIMEDOUT; +} + +static int +do_address(struct i2c_au1550_data *adap, unsigned int addr, int rd, int q) +{ + unsigned long stat; + + /* Reset the FIFOs, clear events. */ + stat = RD(adap, PSC_SMBSTAT); + WR(adap, PSC_SMBEVNT, PSC_SMBEVNT_ALLCLR); + + if (!(stat & PSC_SMBSTAT_TE) || !(stat & PSC_SMBSTAT_RE)) { + WR(adap, PSC_SMBPCR, PSC_SMBPCR_DC); + while ((RD(adap, PSC_SMBPCR) & PSC_SMBPCR_DC) != 0) + cpu_relax(); + udelay(50); + } + + /* Write out the i2c chip address and specify operation */ + addr <<= 1; + if (rd) + addr |= 1; + + /* zero-byte xfers stop immediately */ + if (q) + addr |= PSC_SMBTXRX_STP; + + /* Put byte into fifo, start up master. */ + WR(adap, PSC_SMBTXRX, addr); + WR(adap, PSC_SMBPCR, PSC_SMBPCR_MS); + if (wait_ack(adap)) + return -EIO; + return (q) ? wait_master_done(adap) : 0; +} + +static int wait_for_rx_byte(struct i2c_au1550_data *adap, unsigned char *out) +{ + int j; + + if (wait_xfer_done(adap)) + return -EIO; + + j = adap->xfer_timeout * 100; + do { + j--; + if (j <= 0) + return -EIO; + + if ((RD(adap, PSC_SMBSTAT) & PSC_SMBSTAT_RE) == 0) + j = 0; + else + udelay(1); + } while (j > 0); + + *out = RD(adap, PSC_SMBTXRX); + + return 0; +} + +static int i2c_read(struct i2c_au1550_data *adap, unsigned char *buf, + unsigned int len) +{ + int i; + + if (len == 0) + return 0; + + /* A read is performed by stuffing the transmit fifo with + * zero bytes for timing, waiting for bytes to appear in the + * receive fifo, then reading the bytes. + */ + i = 0; + while (i < (len - 1)) { + WR(adap, PSC_SMBTXRX, 0); + if (wait_for_rx_byte(adap, &buf[i])) + return -EIO; + + i++; + } + + /* The last byte has to indicate transfer done. */ + WR(adap, PSC_SMBTXRX, PSC_SMBTXRX_STP); + if (wait_master_done(adap)) + return -EIO; + + buf[i] = (unsigned char)(RD(adap, PSC_SMBTXRX) & 0xff); + return 0; +} + +static int i2c_write(struct i2c_au1550_data *adap, unsigned char *buf, + unsigned int len) +{ + int i; + unsigned long data; + + if (len == 0) + return 0; + + i = 0; + while (i < (len-1)) { + data = buf[i]; + WR(adap, PSC_SMBTXRX, data); + if (wait_ack(adap)) + return -EIO; + i++; + } + + /* The last byte has to indicate transfer done. */ + data = buf[i]; + data |= PSC_SMBTXRX_STP; + WR(adap, PSC_SMBTXRX, data); + if (wait_master_done(adap)) + return -EIO; + return 0; +} + +static int +au1550_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num) +{ + struct i2c_au1550_data *adap = i2c_adap->algo_data; + struct i2c_msg *p; + int i, err = 0; + + WR(adap, PSC_CTRL, PSC_CTRL_ENABLE); + + for (i = 0; !err && i < num; i++) { + p = &msgs[i]; + err = do_address(adap, p->addr, p->flags & I2C_M_RD, + (p->len == 0)); + if (err || !p->len) + continue; + if (p->flags & I2C_M_RD) + err = i2c_read(adap, p->buf, p->len); + else + err = i2c_write(adap, p->buf, p->len); + } + + /* Return the number of messages processed, or the error code. + */ + if (err == 0) + err = num; + + WR(adap, PSC_CTRL, PSC_CTRL_SUSPEND); + + return err; +} + +static u32 au1550_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm au1550_algo = { + .master_xfer = au1550_xfer, + .functionality = au1550_func, +}; + +static void i2c_au1550_setup(struct i2c_au1550_data *priv) +{ + unsigned long cfg; + + WR(priv, PSC_CTRL, PSC_CTRL_DISABLE); + WR(priv, PSC_SEL, PSC_SEL_PS_SMBUSMODE); + WR(priv, PSC_SMBCFG, 0); + WR(priv, PSC_CTRL, PSC_CTRL_ENABLE); + while ((RD(priv, PSC_SMBSTAT) & PSC_SMBSTAT_SR) == 0) + cpu_relax(); + + cfg = PSC_SMBCFG_RT_FIFO8 | PSC_SMBCFG_TT_FIFO8 | PSC_SMBCFG_DD_DISABLE; + WR(priv, PSC_SMBCFG, cfg); + + /* Divide by 8 to get a 6.25 MHz clock. The later protocol + * timings are based on this clock. + */ + cfg |= PSC_SMBCFG_SET_DIV(PSC_SMBCFG_DIV8); + WR(priv, PSC_SMBCFG, cfg); + WR(priv, PSC_SMBMSK, PSC_SMBMSK_ALLMASK); + + /* Set the protocol timer values. See Table 71 in the + * Au1550 Data Book for standard timing values. + */ + WR(priv, PSC_SMBTMR, PSC_SMBTMR_SET_TH(0) | PSC_SMBTMR_SET_PS(20) | \ + PSC_SMBTMR_SET_PU(20) | PSC_SMBTMR_SET_SH(20) | \ + PSC_SMBTMR_SET_SU(20) | PSC_SMBTMR_SET_CL(20) | \ + PSC_SMBTMR_SET_CH(20)); + + cfg |= PSC_SMBCFG_DE_ENABLE; + WR(priv, PSC_SMBCFG, cfg); + while ((RD(priv, PSC_SMBSTAT) & PSC_SMBSTAT_SR) == 0) + cpu_relax(); + + WR(priv, PSC_CTRL, PSC_CTRL_SUSPEND); +} + +static void i2c_au1550_disable(struct i2c_au1550_data *priv) +{ + WR(priv, PSC_SMBCFG, 0); + WR(priv, PSC_CTRL, PSC_CTRL_DISABLE); +} + +/* + * registering functions to load algorithms at runtime + * Prior to calling us, the 50MHz clock frequency and routing + * must have been set up for the PSC indicated by the adapter. + */ +static int +i2c_au1550_probe(struct platform_device *pdev) +{ + struct i2c_au1550_data *priv; + int ret; + + priv = devm_kzalloc(&pdev->dev, sizeof(struct i2c_au1550_data), + GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->psc_base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(priv->psc_base)) + return PTR_ERR(priv->psc_base); + + priv->xfer_timeout = 200; + + priv->adap.nr = pdev->id; + priv->adap.algo = &au1550_algo; + priv->adap.algo_data = priv; + priv->adap.dev.parent = &pdev->dev; + strscpy(priv->adap.name, "Au1xxx PSC I2C", sizeof(priv->adap.name)); + + /* Now, set up the PSC for SMBus PIO mode. */ + i2c_au1550_setup(priv); + + ret = i2c_add_numbered_adapter(&priv->adap); + if (ret) { + i2c_au1550_disable(priv); + return ret; + } + + platform_set_drvdata(pdev, priv); + return 0; +} + +static void i2c_au1550_remove(struct platform_device *pdev) +{ + struct i2c_au1550_data *priv = platform_get_drvdata(pdev); + + i2c_del_adapter(&priv->adap); + i2c_au1550_disable(priv); +} + +static int i2c_au1550_suspend(struct device *dev) +{ + struct i2c_au1550_data *priv = dev_get_drvdata(dev); + + i2c_au1550_disable(priv); + + return 0; +} + +static int i2c_au1550_resume(struct device *dev) +{ + struct i2c_au1550_data *priv = dev_get_drvdata(dev); + + i2c_au1550_setup(priv); + + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(i2c_au1550_pmops, + i2c_au1550_suspend, i2c_au1550_resume); + +static struct platform_driver au1xpsc_smbus_driver = { + .driver = { + .name = "au1xpsc_smbus", + .pm = pm_sleep_ptr(&i2c_au1550_pmops), + }, + .probe = i2c_au1550_probe, + .remove_new = i2c_au1550_remove, +}; + +module_platform_driver(au1xpsc_smbus_driver); + +MODULE_AUTHOR("Dan Malek, Embedded Edge, LLC."); +MODULE_DESCRIPTION("SMBus adapter Alchemy pb1550"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:au1xpsc_smbus"); diff --git a/drivers/i2c/busses/i2c-axxia.c b/drivers/i2c/busses/i2c-axxia.c new file mode 100644 index 000000000..d7f1e9877 --- /dev/null +++ b/drivers/i2c/busses/i2c-axxia.c @@ -0,0 +1,836 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This driver implements I2C master functionality using the LSI API2C + * controller. + * + * NOTE: The controller has a limitation in that it can only do transfers of + * maximum 255 bytes at a time. If a larger transfer is attempted, error code + * (-EINVAL) is returned. + */ +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> + +#define SCL_WAIT_TIMEOUT_NS 25000000 +#define I2C_XFER_TIMEOUT (msecs_to_jiffies(250)) +#define I2C_STOP_TIMEOUT (msecs_to_jiffies(100)) +#define FIFO_SIZE 8 +#define SEQ_LEN 2 + +#define GLOBAL_CONTROL 0x00 +#define GLOBAL_MST_EN BIT(0) +#define GLOBAL_SLV_EN BIT(1) +#define GLOBAL_IBML_EN BIT(2) +#define INTERRUPT_STATUS 0x04 +#define INTERRUPT_ENABLE 0x08 +#define INT_SLV BIT(1) +#define INT_MST BIT(0) +#define WAIT_TIMER_CONTROL 0x0c +#define WT_EN BIT(15) +#define WT_VALUE(_x) ((_x) & 0x7fff) +#define IBML_TIMEOUT 0x10 +#define IBML_LOW_MEXT 0x14 +#define IBML_LOW_SEXT 0x18 +#define TIMER_CLOCK_DIV 0x1c +#define I2C_BUS_MONITOR 0x20 +#define BM_SDAC BIT(3) +#define BM_SCLC BIT(2) +#define BM_SDAS BIT(1) +#define BM_SCLS BIT(0) +#define SOFT_RESET 0x24 +#define MST_COMMAND 0x28 +#define CMD_BUSY (1<<3) +#define CMD_MANUAL (0x00 | CMD_BUSY) +#define CMD_AUTO (0x01 | CMD_BUSY) +#define CMD_SEQUENCE (0x02 | CMD_BUSY) +#define MST_RX_XFER 0x2c +#define MST_TX_XFER 0x30 +#define MST_ADDR_1 0x34 +#define MST_ADDR_2 0x38 +#define MST_DATA 0x3c +#define MST_TX_FIFO 0x40 +#define MST_RX_FIFO 0x44 +#define MST_INT_ENABLE 0x48 +#define MST_INT_STATUS 0x4c +#define MST_STATUS_RFL (1 << 13) /* RX FIFO serivce */ +#define MST_STATUS_TFL (1 << 12) /* TX FIFO service */ +#define MST_STATUS_SNS (1 << 11) /* Manual mode done */ +#define MST_STATUS_SS (1 << 10) /* Automatic mode done */ +#define MST_STATUS_SCC (1 << 9) /* Stop complete */ +#define MST_STATUS_IP (1 << 8) /* Invalid parameter */ +#define MST_STATUS_TSS (1 << 7) /* Timeout */ +#define MST_STATUS_AL (1 << 6) /* Arbitration lost */ +#define MST_STATUS_ND (1 << 5) /* NAK on data phase */ +#define MST_STATUS_NA (1 << 4) /* NAK on address phase */ +#define MST_STATUS_NAK (MST_STATUS_NA | \ + MST_STATUS_ND) +#define MST_STATUS_ERR (MST_STATUS_NAK | \ + MST_STATUS_AL | \ + MST_STATUS_IP) +#define MST_TX_BYTES_XFRD 0x50 +#define MST_RX_BYTES_XFRD 0x54 +#define SLV_ADDR_DEC_CTL 0x58 +#define SLV_ADDR_DEC_GCE BIT(0) /* ACK to General Call Address from own master (loopback) */ +#define SLV_ADDR_DEC_OGCE BIT(1) /* ACK to General Call Address from external masters */ +#define SLV_ADDR_DEC_SA1E BIT(2) /* ACK to addr_1 enabled */ +#define SLV_ADDR_DEC_SA1M BIT(3) /* 10-bit addressing for addr_1 enabled */ +#define SLV_ADDR_DEC_SA2E BIT(4) /* ACK to addr_2 enabled */ +#define SLV_ADDR_DEC_SA2M BIT(5) /* 10-bit addressing for addr_2 enabled */ +#define SLV_ADDR_1 0x5c +#define SLV_ADDR_2 0x60 +#define SLV_RX_CTL 0x64 +#define SLV_RX_ACSA1 BIT(0) /* Generate ACK for writes to addr_1 */ +#define SLV_RX_ACSA2 BIT(1) /* Generate ACK for writes to addr_2 */ +#define SLV_RX_ACGCA BIT(2) /* ACK data phase transfers to General Call Address */ +#define SLV_DATA 0x68 +#define SLV_RX_FIFO 0x6c +#define SLV_FIFO_DV1 BIT(0) /* Data Valid for addr_1 */ +#define SLV_FIFO_DV2 BIT(1) /* Data Valid for addr_2 */ +#define SLV_FIFO_AS BIT(2) /* (N)ACK Sent */ +#define SLV_FIFO_TNAK BIT(3) /* Timeout NACK */ +#define SLV_FIFO_STRC BIT(4) /* First byte after start condition received */ +#define SLV_FIFO_RSC BIT(5) /* Repeated Start Condition */ +#define SLV_FIFO_STPC BIT(6) /* Stop Condition */ +#define SLV_FIFO_DV (SLV_FIFO_DV1 | SLV_FIFO_DV2) +#define SLV_INT_ENABLE 0x70 +#define SLV_INT_STATUS 0x74 +#define SLV_STATUS_RFH BIT(0) /* FIFO service */ +#define SLV_STATUS_WTC BIT(1) /* Write transfer complete */ +#define SLV_STATUS_SRS1 BIT(2) /* Slave read from addr 1 */ +#define SLV_STATUS_SRRS1 BIT(3) /* Repeated start from addr 1 */ +#define SLV_STATUS_SRND1 BIT(4) /* Read request not following start condition */ +#define SLV_STATUS_SRC1 BIT(5) /* Read canceled */ +#define SLV_STATUS_SRAT1 BIT(6) /* Slave Read timed out */ +#define SLV_STATUS_SRDRE1 BIT(7) /* Data written after timed out */ +#define SLV_READ_DUMMY 0x78 +#define SCL_HIGH_PERIOD 0x80 +#define SCL_LOW_PERIOD 0x84 +#define SPIKE_FLTR_LEN 0x88 +#define SDA_SETUP_TIME 0x8c +#define SDA_HOLD_TIME 0x90 + +/** + * struct axxia_i2c_dev - I2C device context + * @base: pointer to register struct + * @msg: pointer to current message + * @msg_r: pointer to current read message (sequence transfer) + * @msg_xfrd: number of bytes transferred in tx_fifo + * @msg_xfrd_r: number of bytes transferred in rx_fifo + * @msg_err: error code for completed message + * @msg_complete: xfer completion object + * @dev: device reference + * @adapter: core i2c abstraction + * @i2c_clk: clock reference for i2c input clock + * @bus_clk_rate: current i2c bus clock rate + * @last: a flag indicating is this is last message in transfer + */ +struct axxia_i2c_dev { + void __iomem *base; + struct i2c_msg *msg; + struct i2c_msg *msg_r; + size_t msg_xfrd; + size_t msg_xfrd_r; + int msg_err; + struct completion msg_complete; + struct device *dev; + struct i2c_adapter adapter; + struct clk *i2c_clk; + u32 bus_clk_rate; + bool last; + struct i2c_client *slave; + int irq; +}; + +static void i2c_int_disable(struct axxia_i2c_dev *idev, u32 mask) +{ + u32 int_en; + + int_en = readl(idev->base + MST_INT_ENABLE); + writel(int_en & ~mask, idev->base + MST_INT_ENABLE); +} + +static void i2c_int_enable(struct axxia_i2c_dev *idev, u32 mask) +{ + u32 int_en; + + int_en = readl(idev->base + MST_INT_ENABLE); + writel(int_en | mask, idev->base + MST_INT_ENABLE); +} + +/** + * ns_to_clk - Convert time (ns) to clock cycles for the given clock frequency. + */ +static u32 ns_to_clk(u64 ns, u32 clk_mhz) +{ + return div_u64(ns * clk_mhz, 1000); +} + +static int axxia_i2c_init(struct axxia_i2c_dev *idev) +{ + u32 divisor = clk_get_rate(idev->i2c_clk) / idev->bus_clk_rate; + u32 clk_mhz = clk_get_rate(idev->i2c_clk) / 1000000; + u32 t_setup; + u32 t_high, t_low; + u32 tmo_clk; + u32 prescale; + unsigned long timeout; + + dev_dbg(idev->dev, "rate=%uHz per_clk=%uMHz -> ratio=1:%u\n", + idev->bus_clk_rate, clk_mhz, divisor); + + /* Reset controller */ + writel(0x01, idev->base + SOFT_RESET); + timeout = jiffies + msecs_to_jiffies(100); + while (readl(idev->base + SOFT_RESET) & 1) { + if (time_after(jiffies, timeout)) { + dev_warn(idev->dev, "Soft reset failed\n"); + break; + } + } + + /* Enable Master Mode */ + writel(0x1, idev->base + GLOBAL_CONTROL); + + if (idev->bus_clk_rate <= I2C_MAX_STANDARD_MODE_FREQ) { + /* Standard mode SCL 50/50, tSU:DAT = 250 ns */ + t_high = divisor * 1 / 2; + t_low = divisor * 1 / 2; + t_setup = ns_to_clk(250, clk_mhz); + } else { + /* Fast mode SCL 33/66, tSU:DAT = 100 ns */ + t_high = divisor * 1 / 3; + t_low = divisor * 2 / 3; + t_setup = ns_to_clk(100, clk_mhz); + } + + /* SCL High Time */ + writel(t_high, idev->base + SCL_HIGH_PERIOD); + /* SCL Low Time */ + writel(t_low, idev->base + SCL_LOW_PERIOD); + /* SDA Setup Time */ + writel(t_setup, idev->base + SDA_SETUP_TIME); + /* SDA Hold Time, 300ns */ + writel(ns_to_clk(300, clk_mhz), idev->base + SDA_HOLD_TIME); + /* Filter <50ns spikes */ + writel(ns_to_clk(50, clk_mhz), idev->base + SPIKE_FLTR_LEN); + + /* Configure Time-Out Registers */ + tmo_clk = ns_to_clk(SCL_WAIT_TIMEOUT_NS, clk_mhz); + + /* Find prescaler value that makes tmo_clk fit in 15-bits counter. */ + for (prescale = 0; prescale < 15; ++prescale) { + if (tmo_clk <= 0x7fff) + break; + tmo_clk >>= 1; + } + if (tmo_clk > 0x7fff) + tmo_clk = 0x7fff; + + /* Prescale divider (log2) */ + writel(prescale, idev->base + TIMER_CLOCK_DIV); + /* Timeout in divided clocks */ + writel(WT_EN | WT_VALUE(tmo_clk), idev->base + WAIT_TIMER_CONTROL); + + /* Mask all master interrupt bits */ + i2c_int_disable(idev, ~0); + + /* Interrupt enable */ + writel(0x01, idev->base + INTERRUPT_ENABLE); + + return 0; +} + +static int i2c_m_rd(const struct i2c_msg *msg) +{ + return (msg->flags & I2C_M_RD) != 0; +} + +static int i2c_m_ten(const struct i2c_msg *msg) +{ + return (msg->flags & I2C_M_TEN) != 0; +} + +static int i2c_m_recv_len(const struct i2c_msg *msg) +{ + return (msg->flags & I2C_M_RECV_LEN) != 0; +} + +/** + * axxia_i2c_empty_rx_fifo - Fetch data from RX FIFO and update SMBus block + * transfer length if this is the first byte of such a transfer. + */ +static int axxia_i2c_empty_rx_fifo(struct axxia_i2c_dev *idev) +{ + struct i2c_msg *msg = idev->msg_r; + size_t rx_fifo_avail = readl(idev->base + MST_RX_FIFO); + int bytes_to_transfer = min(rx_fifo_avail, msg->len - idev->msg_xfrd_r); + + while (bytes_to_transfer-- > 0) { + int c = readl(idev->base + MST_DATA); + + if (idev->msg_xfrd_r == 0 && i2c_m_recv_len(msg)) { + /* + * Check length byte for SMBus block read + */ + if (c <= 0 || c > I2C_SMBUS_BLOCK_MAX) { + idev->msg_err = -EPROTO; + i2c_int_disable(idev, ~MST_STATUS_TSS); + complete(&idev->msg_complete); + break; + } + msg->len = 1 + c; + writel(msg->len, idev->base + MST_RX_XFER); + } + msg->buf[idev->msg_xfrd_r++] = c; + } + + return 0; +} + +/** + * axxia_i2c_fill_tx_fifo - Fill TX FIFO from current message buffer. + * @return: Number of bytes left to transfer. + */ +static int axxia_i2c_fill_tx_fifo(struct axxia_i2c_dev *idev) +{ + struct i2c_msg *msg = idev->msg; + size_t tx_fifo_avail = FIFO_SIZE - readl(idev->base + MST_TX_FIFO); + int bytes_to_transfer = min(tx_fifo_avail, msg->len - idev->msg_xfrd); + int ret = msg->len - idev->msg_xfrd - bytes_to_transfer; + + while (bytes_to_transfer-- > 0) + writel(msg->buf[idev->msg_xfrd++], idev->base + MST_DATA); + + return ret; +} + +static void axxia_i2c_slv_fifo_event(struct axxia_i2c_dev *idev) +{ + u32 fifo_status = readl(idev->base + SLV_RX_FIFO); + u8 val; + + dev_dbg(idev->dev, "slave irq fifo_status=0x%x\n", fifo_status); + + if (fifo_status & SLV_FIFO_DV1) { + if (fifo_status & SLV_FIFO_STRC) + i2c_slave_event(idev->slave, + I2C_SLAVE_WRITE_REQUESTED, &val); + + val = readl(idev->base + SLV_DATA); + i2c_slave_event(idev->slave, I2C_SLAVE_WRITE_RECEIVED, &val); + } + if (fifo_status & SLV_FIFO_STPC) { + readl(idev->base + SLV_DATA); /* dummy read */ + i2c_slave_event(idev->slave, I2C_SLAVE_STOP, &val); + } + if (fifo_status & SLV_FIFO_RSC) + readl(idev->base + SLV_DATA); /* dummy read */ +} + +static irqreturn_t axxia_i2c_slv_isr(struct axxia_i2c_dev *idev) +{ + u32 status = readl(idev->base + SLV_INT_STATUS); + u8 val; + + dev_dbg(idev->dev, "slave irq status=0x%x\n", status); + + if (status & SLV_STATUS_RFH) + axxia_i2c_slv_fifo_event(idev); + if (status & SLV_STATUS_SRS1) { + i2c_slave_event(idev->slave, I2C_SLAVE_READ_REQUESTED, &val); + writel(val, idev->base + SLV_DATA); + } + if (status & SLV_STATUS_SRND1) { + i2c_slave_event(idev->slave, I2C_SLAVE_READ_PROCESSED, &val); + writel(val, idev->base + SLV_DATA); + } + if (status & SLV_STATUS_SRC1) + i2c_slave_event(idev->slave, I2C_SLAVE_STOP, &val); + + writel(INT_SLV, idev->base + INTERRUPT_STATUS); + return IRQ_HANDLED; +} + +static irqreturn_t axxia_i2c_isr(int irq, void *_dev) +{ + struct axxia_i2c_dev *idev = _dev; + irqreturn_t ret = IRQ_NONE; + u32 status; + + status = readl(idev->base + INTERRUPT_STATUS); + + if (status & INT_SLV) + ret = axxia_i2c_slv_isr(idev); + if (!(status & INT_MST)) + return ret; + + /* Read interrupt status bits */ + status = readl(idev->base + MST_INT_STATUS); + + if (!idev->msg) { + dev_warn(idev->dev, "unexpected interrupt\n"); + goto out; + } + + /* RX FIFO needs service? */ + if (i2c_m_rd(idev->msg_r) && (status & MST_STATUS_RFL)) + axxia_i2c_empty_rx_fifo(idev); + + /* TX FIFO needs service? */ + if (!i2c_m_rd(idev->msg) && (status & MST_STATUS_TFL)) { + if (axxia_i2c_fill_tx_fifo(idev) == 0) + i2c_int_disable(idev, MST_STATUS_TFL); + } + + if (unlikely(status & MST_STATUS_ERR)) { + /* Transfer error */ + i2c_int_disable(idev, ~0); + if (status & MST_STATUS_AL) + idev->msg_err = -EAGAIN; + else if (status & MST_STATUS_NAK) + idev->msg_err = -ENXIO; + else + idev->msg_err = -EIO; + dev_dbg(idev->dev, "error %#x, addr=%#x rx=%u/%u tx=%u/%u\n", + status, + idev->msg->addr, + readl(idev->base + MST_RX_BYTES_XFRD), + readl(idev->base + MST_RX_XFER), + readl(idev->base + MST_TX_BYTES_XFRD), + readl(idev->base + MST_TX_XFER)); + complete(&idev->msg_complete); + } else if (status & MST_STATUS_SCC) { + /* Stop completed */ + i2c_int_disable(idev, ~MST_STATUS_TSS); + complete(&idev->msg_complete); + } else if (status & (MST_STATUS_SNS | MST_STATUS_SS)) { + /* Transfer done */ + int mask = idev->last ? ~0 : ~MST_STATUS_TSS; + + i2c_int_disable(idev, mask); + if (i2c_m_rd(idev->msg_r) && idev->msg_xfrd_r < idev->msg_r->len) + axxia_i2c_empty_rx_fifo(idev); + complete(&idev->msg_complete); + } else if (status & MST_STATUS_TSS) { + /* Transfer timeout */ + idev->msg_err = -ETIMEDOUT; + i2c_int_disable(idev, ~MST_STATUS_TSS); + complete(&idev->msg_complete); + } + +out: + /* Clear interrupt */ + writel(INT_MST, idev->base + INTERRUPT_STATUS); + + return IRQ_HANDLED; +} + +static void axxia_i2c_set_addr(struct axxia_i2c_dev *idev, struct i2c_msg *msg) +{ + u32 addr_1, addr_2; + + if (i2c_m_ten(msg)) { + /* 10-bit address + * addr_1: 5'b11110 | addr[9:8] | (R/nW) + * addr_2: addr[7:0] + */ + addr_1 = 0xF0 | ((msg->addr >> 7) & 0x06); + if (i2c_m_rd(msg)) + addr_1 |= 1; /* Set the R/nW bit of the address */ + addr_2 = msg->addr & 0xFF; + } else { + /* 7-bit address + * addr_1: addr[6:0] | (R/nW) + * addr_2: dont care + */ + addr_1 = i2c_8bit_addr_from_msg(msg); + addr_2 = 0; + } + + writel(addr_1, idev->base + MST_ADDR_1); + writel(addr_2, idev->base + MST_ADDR_2); +} + +/* The NAK interrupt will be sent _before_ issuing STOP command + * so the controller might still be busy processing it. No + * interrupt will be sent at the end so we have to poll for it + */ +static int axxia_i2c_handle_seq_nak(struct axxia_i2c_dev *idev) +{ + unsigned long timeout = jiffies + I2C_XFER_TIMEOUT; + + do { + if ((readl(idev->base + MST_COMMAND) & CMD_BUSY) == 0) + return 0; + usleep_range(1, 100); + } while (time_before(jiffies, timeout)); + + return -ETIMEDOUT; +} + +static int axxia_i2c_xfer_seq(struct axxia_i2c_dev *idev, struct i2c_msg msgs[]) +{ + u32 int_mask = MST_STATUS_ERR | MST_STATUS_SS | MST_STATUS_RFL; + u32 rlen = i2c_m_recv_len(&msgs[1]) ? I2C_SMBUS_BLOCK_MAX : msgs[1].len; + unsigned long time_left; + + axxia_i2c_set_addr(idev, &msgs[0]); + + writel(msgs[0].len, idev->base + MST_TX_XFER); + writel(rlen, idev->base + MST_RX_XFER); + + idev->msg = &msgs[0]; + idev->msg_r = &msgs[1]; + idev->msg_xfrd = 0; + idev->msg_xfrd_r = 0; + idev->last = true; + axxia_i2c_fill_tx_fifo(idev); + + writel(CMD_SEQUENCE, idev->base + MST_COMMAND); + + reinit_completion(&idev->msg_complete); + i2c_int_enable(idev, int_mask); + + time_left = wait_for_completion_timeout(&idev->msg_complete, + I2C_XFER_TIMEOUT); + + if (idev->msg_err == -ENXIO) { + if (axxia_i2c_handle_seq_nak(idev)) + axxia_i2c_init(idev); + } else if (readl(idev->base + MST_COMMAND) & CMD_BUSY) { + dev_warn(idev->dev, "busy after xfer\n"); + } + + if (time_left == 0) { + idev->msg_err = -ETIMEDOUT; + i2c_recover_bus(&idev->adapter); + axxia_i2c_init(idev); + } + + if (unlikely(idev->msg_err) && idev->msg_err != -ENXIO) + axxia_i2c_init(idev); + + return idev->msg_err; +} + +static int axxia_i2c_xfer_msg(struct axxia_i2c_dev *idev, struct i2c_msg *msg, + bool last) +{ + u32 int_mask = MST_STATUS_ERR; + u32 rx_xfer, tx_xfer; + unsigned long time_left; + unsigned int wt_value; + + idev->msg = msg; + idev->msg_r = msg; + idev->msg_xfrd = 0; + idev->msg_xfrd_r = 0; + idev->last = last; + reinit_completion(&idev->msg_complete); + + axxia_i2c_set_addr(idev, msg); + + if (i2c_m_rd(msg)) { + /* I2C read transfer */ + rx_xfer = i2c_m_recv_len(msg) ? I2C_SMBUS_BLOCK_MAX : msg->len; + tx_xfer = 0; + } else { + /* I2C write transfer */ + rx_xfer = 0; + tx_xfer = msg->len; + } + + writel(rx_xfer, idev->base + MST_RX_XFER); + writel(tx_xfer, idev->base + MST_TX_XFER); + + if (i2c_m_rd(msg)) + int_mask |= MST_STATUS_RFL; + else if (axxia_i2c_fill_tx_fifo(idev) != 0) + int_mask |= MST_STATUS_TFL; + + wt_value = WT_VALUE(readl(idev->base + WAIT_TIMER_CONTROL)); + /* Disable wait timer temporarly */ + writel(wt_value, idev->base + WAIT_TIMER_CONTROL); + /* Check if timeout error happened */ + if (idev->msg_err) + goto out; + + if (!last) { + writel(CMD_MANUAL, idev->base + MST_COMMAND); + int_mask |= MST_STATUS_SNS; + } else { + writel(CMD_AUTO, idev->base + MST_COMMAND); + int_mask |= MST_STATUS_SS; + } + + writel(WT_EN | wt_value, idev->base + WAIT_TIMER_CONTROL); + + i2c_int_enable(idev, int_mask); + + time_left = wait_for_completion_timeout(&idev->msg_complete, + I2C_XFER_TIMEOUT); + + i2c_int_disable(idev, int_mask); + + if (readl(idev->base + MST_COMMAND) & CMD_BUSY) + dev_warn(idev->dev, "busy after xfer\n"); + + if (time_left == 0) { + idev->msg_err = -ETIMEDOUT; + i2c_recover_bus(&idev->adapter); + axxia_i2c_init(idev); + } + +out: + if (unlikely(idev->msg_err) && idev->msg_err != -ENXIO && + idev->msg_err != -ETIMEDOUT) + axxia_i2c_init(idev); + + return idev->msg_err; +} + +/* This function checks if the msgs[] array contains messages compatible with + * Sequence mode of operation. This mode assumes there will be exactly one + * write of non-zero length followed by exactly one read of non-zero length, + * both targeted at the same client device. + */ +static bool axxia_i2c_sequence_ok(struct i2c_msg msgs[], int num) +{ + return num == SEQ_LEN && !i2c_m_rd(&msgs[0]) && i2c_m_rd(&msgs[1]) && + msgs[0].len > 0 && msgs[0].len <= FIFO_SIZE && + msgs[1].len > 0 && msgs[0].addr == msgs[1].addr; +} + +static int +axxia_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + struct axxia_i2c_dev *idev = i2c_get_adapdata(adap); + int i; + int ret = 0; + + idev->msg_err = 0; + + if (axxia_i2c_sequence_ok(msgs, num)) { + ret = axxia_i2c_xfer_seq(idev, msgs); + return ret ? : SEQ_LEN; + } + + i2c_int_enable(idev, MST_STATUS_TSS); + + for (i = 0; ret == 0 && i < num; ++i) + ret = axxia_i2c_xfer_msg(idev, &msgs[i], i == (num - 1)); + + return ret ? : i; +} + +static int axxia_i2c_get_scl(struct i2c_adapter *adap) +{ + struct axxia_i2c_dev *idev = i2c_get_adapdata(adap); + + return !!(readl(idev->base + I2C_BUS_MONITOR) & BM_SCLS); +} + +static void axxia_i2c_set_scl(struct i2c_adapter *adap, int val) +{ + struct axxia_i2c_dev *idev = i2c_get_adapdata(adap); + u32 tmp; + + /* Preserve SDA Control */ + tmp = readl(idev->base + I2C_BUS_MONITOR) & BM_SDAC; + if (!val) + tmp |= BM_SCLC; + writel(tmp, idev->base + I2C_BUS_MONITOR); +} + +static int axxia_i2c_get_sda(struct i2c_adapter *adap) +{ + struct axxia_i2c_dev *idev = i2c_get_adapdata(adap); + + return !!(readl(idev->base + I2C_BUS_MONITOR) & BM_SDAS); +} + +static struct i2c_bus_recovery_info axxia_i2c_recovery_info = { + .recover_bus = i2c_generic_scl_recovery, + .get_scl = axxia_i2c_get_scl, + .set_scl = axxia_i2c_set_scl, + .get_sda = axxia_i2c_get_sda, +}; + +static u32 axxia_i2c_func(struct i2c_adapter *adap) +{ + u32 caps = (I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | + I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_BLOCK_DATA); + return caps; +} + +static int axxia_i2c_reg_slave(struct i2c_client *slave) +{ + struct axxia_i2c_dev *idev = i2c_get_adapdata(slave->adapter); + u32 slv_int_mask = SLV_STATUS_RFH; + u32 dec_ctl; + + if (idev->slave) + return -EBUSY; + + idev->slave = slave; + + /* Enable slave mode as well */ + writel(GLOBAL_MST_EN | GLOBAL_SLV_EN, idev->base + GLOBAL_CONTROL); + writel(INT_MST | INT_SLV, idev->base + INTERRUPT_ENABLE); + + /* Set slave address */ + dec_ctl = SLV_ADDR_DEC_SA1E; + if (slave->flags & I2C_CLIENT_TEN) + dec_ctl |= SLV_ADDR_DEC_SA1M; + + writel(SLV_RX_ACSA1, idev->base + SLV_RX_CTL); + writel(dec_ctl, idev->base + SLV_ADDR_DEC_CTL); + writel(slave->addr, idev->base + SLV_ADDR_1); + + /* Enable interrupts */ + slv_int_mask |= SLV_STATUS_SRS1 | SLV_STATUS_SRRS1 | SLV_STATUS_SRND1; + slv_int_mask |= SLV_STATUS_SRC1; + writel(slv_int_mask, idev->base + SLV_INT_ENABLE); + + return 0; +} + +static int axxia_i2c_unreg_slave(struct i2c_client *slave) +{ + struct axxia_i2c_dev *idev = i2c_get_adapdata(slave->adapter); + + /* Disable slave mode */ + writel(GLOBAL_MST_EN, idev->base + GLOBAL_CONTROL); + writel(INT_MST, idev->base + INTERRUPT_ENABLE); + + synchronize_irq(idev->irq); + + idev->slave = NULL; + + return 0; +} + +static const struct i2c_algorithm axxia_i2c_algo = { + .master_xfer = axxia_i2c_xfer, + .functionality = axxia_i2c_func, + .reg_slave = axxia_i2c_reg_slave, + .unreg_slave = axxia_i2c_unreg_slave, +}; + +static const struct i2c_adapter_quirks axxia_i2c_quirks = { + .max_read_len = 255, + .max_write_len = 255, +}; + +static int axxia_i2c_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct axxia_i2c_dev *idev = NULL; + void __iomem *base; + int ret = 0; + + idev = devm_kzalloc(&pdev->dev, sizeof(*idev), GFP_KERNEL); + if (!idev) + return -ENOMEM; + + base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(base)) + return PTR_ERR(base); + + idev->irq = platform_get_irq(pdev, 0); + if (idev->irq < 0) + return idev->irq; + + idev->i2c_clk = devm_clk_get(&pdev->dev, "i2c"); + if (IS_ERR(idev->i2c_clk)) { + dev_err(&pdev->dev, "missing clock\n"); + return PTR_ERR(idev->i2c_clk); + } + + idev->base = base; + idev->dev = &pdev->dev; + init_completion(&idev->msg_complete); + + of_property_read_u32(np, "clock-frequency", &idev->bus_clk_rate); + if (idev->bus_clk_rate == 0) + idev->bus_clk_rate = I2C_MAX_STANDARD_MODE_FREQ; /* default clock rate */ + + ret = clk_prepare_enable(idev->i2c_clk); + if (ret) { + dev_err(&pdev->dev, "failed to enable clock\n"); + return ret; + } + + ret = axxia_i2c_init(idev); + if (ret) { + dev_err(&pdev->dev, "failed to initialize\n"); + goto error_disable_clk; + } + + ret = devm_request_irq(&pdev->dev, idev->irq, axxia_i2c_isr, 0, + pdev->name, idev); + if (ret) { + dev_err(&pdev->dev, "failed to claim IRQ%d\n", idev->irq); + goto error_disable_clk; + } + + i2c_set_adapdata(&idev->adapter, idev); + strscpy(idev->adapter.name, pdev->name, sizeof(idev->adapter.name)); + idev->adapter.owner = THIS_MODULE; + idev->adapter.algo = &axxia_i2c_algo; + idev->adapter.bus_recovery_info = &axxia_i2c_recovery_info; + idev->adapter.quirks = &axxia_i2c_quirks; + idev->adapter.dev.parent = &pdev->dev; + idev->adapter.dev.of_node = pdev->dev.of_node; + + platform_set_drvdata(pdev, idev); + + ret = i2c_add_adapter(&idev->adapter); + if (ret) + goto error_disable_clk; + + return 0; + +error_disable_clk: + clk_disable_unprepare(idev->i2c_clk); + return ret; +} + +static void axxia_i2c_remove(struct platform_device *pdev) +{ + struct axxia_i2c_dev *idev = platform_get_drvdata(pdev); + + clk_disable_unprepare(idev->i2c_clk); + i2c_del_adapter(&idev->adapter); +} + +/* Match table for of_platform binding */ +static const struct of_device_id axxia_i2c_of_match[] = { + { .compatible = "lsi,api2c", }, + {}, +}; + +MODULE_DEVICE_TABLE(of, axxia_i2c_of_match); + +static struct platform_driver axxia_i2c_driver = { + .probe = axxia_i2c_probe, + .remove_new = axxia_i2c_remove, + .driver = { + .name = "axxia-i2c", + .of_match_table = axxia_i2c_of_match, + }, +}; + +module_platform_driver(axxia_i2c_driver); + +MODULE_DESCRIPTION("Axxia I2C Bus driver"); +MODULE_AUTHOR("Anders Berg <anders.berg@lsi.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c b/drivers/i2c/busses/i2c-bcm-iproc.c new file mode 100644 index 000000000..e905734c2 --- /dev/null +++ b/drivers/i2c/busses/i2c-bcm-iproc.c @@ -0,0 +1,1275 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (C) 2014 Broadcom Corporation + +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#define IDM_CTRL_DIRECT_OFFSET 0x00 +#define CFG_OFFSET 0x00 +#define CFG_RESET_SHIFT 31 +#define CFG_EN_SHIFT 30 +#define CFG_SLAVE_ADDR_0_SHIFT 28 +#define CFG_M_RETRY_CNT_SHIFT 16 +#define CFG_M_RETRY_CNT_MASK 0x0f + +#define TIM_CFG_OFFSET 0x04 +#define TIM_CFG_MODE_400_SHIFT 31 +#define TIM_RAND_SLAVE_STRETCH_SHIFT 24 +#define TIM_RAND_SLAVE_STRETCH_MASK 0x7f +#define TIM_PERIODIC_SLAVE_STRETCH_SHIFT 16 +#define TIM_PERIODIC_SLAVE_STRETCH_MASK 0x7f + +#define S_CFG_SMBUS_ADDR_OFFSET 0x08 +#define S_CFG_EN_NIC_SMB_ADDR3_SHIFT 31 +#define S_CFG_NIC_SMB_ADDR3_SHIFT 24 +#define S_CFG_NIC_SMB_ADDR3_MASK 0x7f +#define S_CFG_EN_NIC_SMB_ADDR2_SHIFT 23 +#define S_CFG_NIC_SMB_ADDR2_SHIFT 16 +#define S_CFG_NIC_SMB_ADDR2_MASK 0x7f +#define S_CFG_EN_NIC_SMB_ADDR1_SHIFT 15 +#define S_CFG_NIC_SMB_ADDR1_SHIFT 8 +#define S_CFG_NIC_SMB_ADDR1_MASK 0x7f +#define S_CFG_EN_NIC_SMB_ADDR0_SHIFT 7 +#define S_CFG_NIC_SMB_ADDR0_SHIFT 0 +#define S_CFG_NIC_SMB_ADDR0_MASK 0x7f + +#define M_FIFO_CTRL_OFFSET 0x0c +#define M_FIFO_RX_FLUSH_SHIFT 31 +#define M_FIFO_TX_FLUSH_SHIFT 30 +#define M_FIFO_RX_CNT_SHIFT 16 +#define M_FIFO_RX_CNT_MASK 0x7f +#define M_FIFO_RX_THLD_SHIFT 8 +#define M_FIFO_RX_THLD_MASK 0x3f + +#define S_FIFO_CTRL_OFFSET 0x10 +#define S_FIFO_RX_FLUSH_SHIFT 31 +#define S_FIFO_TX_FLUSH_SHIFT 30 +#define S_FIFO_RX_CNT_SHIFT 16 +#define S_FIFO_RX_CNT_MASK 0x7f +#define S_FIFO_RX_THLD_SHIFT 8 +#define S_FIFO_RX_THLD_MASK 0x3f + +#define M_CMD_OFFSET 0x30 +#define M_CMD_START_BUSY_SHIFT 31 +#define M_CMD_STATUS_SHIFT 25 +#define M_CMD_STATUS_MASK 0x07 +#define M_CMD_STATUS_SUCCESS 0x0 +#define M_CMD_STATUS_LOST_ARB 0x1 +#define M_CMD_STATUS_NACK_ADDR 0x2 +#define M_CMD_STATUS_NACK_DATA 0x3 +#define M_CMD_STATUS_TIMEOUT 0x4 +#define M_CMD_STATUS_FIFO_UNDERRUN 0x5 +#define M_CMD_STATUS_RX_FIFO_FULL 0x6 +#define M_CMD_PROTOCOL_SHIFT 9 +#define M_CMD_PROTOCOL_MASK 0xf +#define M_CMD_PROTOCOL_QUICK 0x0 +#define M_CMD_PROTOCOL_BLK_WR 0x7 +#define M_CMD_PROTOCOL_BLK_RD 0x8 +#define M_CMD_PROTOCOL_PROCESS 0xa +#define M_CMD_PEC_SHIFT 8 +#define M_CMD_RD_CNT_SHIFT 0 +#define M_CMD_RD_CNT_MASK 0xff + +#define S_CMD_OFFSET 0x34 +#define S_CMD_START_BUSY_SHIFT 31 +#define S_CMD_STATUS_SHIFT 23 +#define S_CMD_STATUS_MASK 0x07 +#define S_CMD_STATUS_SUCCESS 0x0 +#define S_CMD_STATUS_TIMEOUT 0x5 +#define S_CMD_STATUS_MASTER_ABORT 0x7 + +#define IE_OFFSET 0x38 +#define IE_M_RX_FIFO_FULL_SHIFT 31 +#define IE_M_RX_THLD_SHIFT 30 +#define IE_M_START_BUSY_SHIFT 28 +#define IE_M_TX_UNDERRUN_SHIFT 27 +#define IE_S_RX_FIFO_FULL_SHIFT 26 +#define IE_S_RX_THLD_SHIFT 25 +#define IE_S_RX_EVENT_SHIFT 24 +#define IE_S_START_BUSY_SHIFT 23 +#define IE_S_TX_UNDERRUN_SHIFT 22 +#define IE_S_RD_EVENT_SHIFT 21 + +#define IS_OFFSET 0x3c +#define IS_M_RX_FIFO_FULL_SHIFT 31 +#define IS_M_RX_THLD_SHIFT 30 +#define IS_M_START_BUSY_SHIFT 28 +#define IS_M_TX_UNDERRUN_SHIFT 27 +#define IS_S_RX_FIFO_FULL_SHIFT 26 +#define IS_S_RX_THLD_SHIFT 25 +#define IS_S_RX_EVENT_SHIFT 24 +#define IS_S_START_BUSY_SHIFT 23 +#define IS_S_TX_UNDERRUN_SHIFT 22 +#define IS_S_RD_EVENT_SHIFT 21 + +#define M_TX_OFFSET 0x40 +#define M_TX_WR_STATUS_SHIFT 31 +#define M_TX_DATA_SHIFT 0 +#define M_TX_DATA_MASK 0xff + +#define M_RX_OFFSET 0x44 +#define M_RX_STATUS_SHIFT 30 +#define M_RX_STATUS_MASK 0x03 +#define M_RX_PEC_ERR_SHIFT 29 +#define M_RX_DATA_SHIFT 0 +#define M_RX_DATA_MASK 0xff + +#define S_TX_OFFSET 0x48 +#define S_TX_WR_STATUS_SHIFT 31 +#define S_TX_DATA_SHIFT 0 +#define S_TX_DATA_MASK 0xff + +#define S_RX_OFFSET 0x4c +#define S_RX_STATUS_SHIFT 30 +#define S_RX_STATUS_MASK 0x03 +#define S_RX_PEC_ERR_SHIFT 29 +#define S_RX_DATA_SHIFT 0 +#define S_RX_DATA_MASK 0xff + +#define I2C_TIMEOUT_MSEC 50000 +#define M_TX_RX_FIFO_SIZE 64 +#define M_RX_FIFO_MAX_THLD_VALUE (M_TX_RX_FIFO_SIZE - 1) + +#define M_RX_MAX_READ_LEN 255 +#define M_RX_FIFO_THLD_VALUE 50 + +#define IE_M_ALL_INTERRUPT_SHIFT 27 +#define IE_M_ALL_INTERRUPT_MASK 0x1e + +#define SLAVE_READ_WRITE_BIT_MASK 0x1 +#define SLAVE_READ_WRITE_BIT_SHIFT 0x1 +#define SLAVE_MAX_SIZE_TRANSACTION 64 +#define SLAVE_CLOCK_STRETCH_TIME 25 + +#define IE_S_ALL_INTERRUPT_SHIFT 21 +#define IE_S_ALL_INTERRUPT_MASK 0x3f +/* + * It takes ~18us to reading 10bytes of data, hence to keep tasklet + * running for less time, max slave read per tasklet is set to 10 bytes. + */ +#define MAX_SLAVE_RX_PER_INT 10 + +enum i2c_slave_read_status { + I2C_SLAVE_RX_FIFO_EMPTY = 0, + I2C_SLAVE_RX_START, + I2C_SLAVE_RX_DATA, + I2C_SLAVE_RX_END, +}; + +enum bus_speed_index { + I2C_SPD_100K = 0, + I2C_SPD_400K, +}; + +enum bcm_iproc_i2c_type { + IPROC_I2C, + IPROC_I2C_NIC +}; + +struct bcm_iproc_i2c_dev { + struct device *device; + enum bcm_iproc_i2c_type type; + int irq; + + void __iomem *base; + void __iomem *idm_base; + + u32 ape_addr_mask; + + /* lock for indirect access through IDM */ + spinlock_t idm_lock; + + struct i2c_adapter adapter; + unsigned int bus_speed; + + struct completion done; + int xfer_is_done; + + struct i2c_msg *msg; + + struct i2c_client *slave; + + /* bytes that have been transferred */ + unsigned int tx_bytes; + /* bytes that have been read */ + unsigned int rx_bytes; + unsigned int thld_bytes; + + bool slave_rx_only; + bool rx_start_rcvd; + bool slave_read_complete; + u32 tx_underrun; + u32 slave_int_mask; + struct tasklet_struct slave_rx_tasklet; +}; + +/* tasklet to process slave rx data */ +static void slave_rx_tasklet_fn(unsigned long); + +/* + * Can be expanded in the future if more interrupt status bits are utilized + */ +#define ISR_MASK (BIT(IS_M_START_BUSY_SHIFT) | BIT(IS_M_TX_UNDERRUN_SHIFT)\ + | BIT(IS_M_RX_THLD_SHIFT)) + +#define ISR_MASK_SLAVE (BIT(IS_S_START_BUSY_SHIFT)\ + | BIT(IS_S_RX_EVENT_SHIFT) | BIT(IS_S_RD_EVENT_SHIFT)\ + | BIT(IS_S_TX_UNDERRUN_SHIFT) | BIT(IS_S_RX_FIFO_FULL_SHIFT)\ + | BIT(IS_S_RX_THLD_SHIFT)) + +static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave); +static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave); +static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c, + bool enable); + +static inline u32 iproc_i2c_rd_reg(struct bcm_iproc_i2c_dev *iproc_i2c, + u32 offset) +{ + u32 val; + unsigned long flags; + + if (iproc_i2c->idm_base) { + spin_lock_irqsave(&iproc_i2c->idm_lock, flags); + writel(iproc_i2c->ape_addr_mask, + iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET); + val = readl(iproc_i2c->base + offset); + spin_unlock_irqrestore(&iproc_i2c->idm_lock, flags); + } else { + val = readl(iproc_i2c->base + offset); + } + + return val; +} + +static inline void iproc_i2c_wr_reg(struct bcm_iproc_i2c_dev *iproc_i2c, + u32 offset, u32 val) +{ + unsigned long flags; + + if (iproc_i2c->idm_base) { + spin_lock_irqsave(&iproc_i2c->idm_lock, flags); + writel(iproc_i2c->ape_addr_mask, + iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET); + writel(val, iproc_i2c->base + offset); + spin_unlock_irqrestore(&iproc_i2c->idm_lock, flags); + } else { + writel(val, iproc_i2c->base + offset); + } +} + +static void bcm_iproc_i2c_slave_init( + struct bcm_iproc_i2c_dev *iproc_i2c, bool need_reset) +{ + u32 val; + + iproc_i2c->tx_underrun = 0; + if (need_reset) { + /* put controller in reset */ + val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET); + val |= BIT(CFG_RESET_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val); + + /* wait 100 usec per spec */ + udelay(100); + + /* bring controller out of reset */ + val &= ~(BIT(CFG_RESET_SHIFT)); + iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val); + } + + /* flush TX/RX FIFOs */ + val = (BIT(S_FIFO_RX_FLUSH_SHIFT) | BIT(S_FIFO_TX_FLUSH_SHIFT)); + iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, val); + + /* Maximum slave stretch time */ + val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET); + val &= ~(TIM_RAND_SLAVE_STRETCH_MASK << TIM_RAND_SLAVE_STRETCH_SHIFT); + val |= (SLAVE_CLOCK_STRETCH_TIME << TIM_RAND_SLAVE_STRETCH_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val); + + /* Configure the slave address */ + val = iproc_i2c_rd_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET); + val |= BIT(S_CFG_EN_NIC_SMB_ADDR3_SHIFT); + val &= ~(S_CFG_NIC_SMB_ADDR3_MASK << S_CFG_NIC_SMB_ADDR3_SHIFT); + val |= (iproc_i2c->slave->addr << S_CFG_NIC_SMB_ADDR3_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET, val); + + /* clear all pending slave interrupts */ + iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, ISR_MASK_SLAVE); + + /* Enable interrupt register to indicate a valid byte in receive fifo */ + val = BIT(IE_S_RX_EVENT_SHIFT); + /* Enable interrupt register to indicate Slave Rx FIFO Full */ + val |= BIT(IE_S_RX_FIFO_FULL_SHIFT); + /* Enable interrupt register to indicate a Master read transaction */ + val |= BIT(IE_S_RD_EVENT_SHIFT); + /* Enable interrupt register for the Slave BUSY command */ + val |= BIT(IE_S_START_BUSY_SHIFT); + iproc_i2c->slave_int_mask = val; + iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val); +} + +static bool bcm_iproc_i2c_check_slave_status + (struct bcm_iproc_i2c_dev *iproc_i2c, u32 status) +{ + u32 val; + bool recover = false; + + /* check slave transmit status only if slave is transmitting */ + if (!iproc_i2c->slave_rx_only) { + val = iproc_i2c_rd_reg(iproc_i2c, S_CMD_OFFSET); + /* status is valid only when START_BUSY is cleared */ + if (!(val & BIT(S_CMD_START_BUSY_SHIFT))) { + val = (val >> S_CMD_STATUS_SHIFT) & S_CMD_STATUS_MASK; + if (val == S_CMD_STATUS_TIMEOUT || + val == S_CMD_STATUS_MASTER_ABORT) { + dev_warn(iproc_i2c->device, + (val == S_CMD_STATUS_TIMEOUT) ? + "slave random stretch time timeout\n" : + "Master aborted read transaction\n"); + recover = true; + } + } + } + + /* RX_EVENT is not valid when START_BUSY is set */ + if ((status & BIT(IS_S_RX_EVENT_SHIFT)) && + (status & BIT(IS_S_START_BUSY_SHIFT))) { + dev_warn(iproc_i2c->device, "Slave aborted read transaction\n"); + recover = true; + } + + if (recover) { + /* re-initialize i2c for recovery */ + bcm_iproc_i2c_enable_disable(iproc_i2c, false); + bcm_iproc_i2c_slave_init(iproc_i2c, true); + bcm_iproc_i2c_enable_disable(iproc_i2c, true); + } + + return recover; +} + +static void bcm_iproc_i2c_slave_read(struct bcm_iproc_i2c_dev *iproc_i2c) +{ + u8 rx_data, rx_status; + u32 rx_bytes = 0; + u32 val; + + while (rx_bytes < MAX_SLAVE_RX_PER_INT) { + val = iproc_i2c_rd_reg(iproc_i2c, S_RX_OFFSET); + rx_status = (val >> S_RX_STATUS_SHIFT) & S_RX_STATUS_MASK; + rx_data = ((val >> S_RX_DATA_SHIFT) & S_RX_DATA_MASK); + + if (rx_status == I2C_SLAVE_RX_START) { + /* Start of SMBUS Master write */ + i2c_slave_event(iproc_i2c->slave, + I2C_SLAVE_WRITE_REQUESTED, &rx_data); + iproc_i2c->rx_start_rcvd = true; + iproc_i2c->slave_read_complete = false; + } else if (rx_status == I2C_SLAVE_RX_DATA && + iproc_i2c->rx_start_rcvd) { + /* Middle of SMBUS Master write */ + i2c_slave_event(iproc_i2c->slave, + I2C_SLAVE_WRITE_RECEIVED, &rx_data); + } else if (rx_status == I2C_SLAVE_RX_END && + iproc_i2c->rx_start_rcvd) { + /* End of SMBUS Master write */ + if (iproc_i2c->slave_rx_only) + i2c_slave_event(iproc_i2c->slave, + I2C_SLAVE_WRITE_RECEIVED, + &rx_data); + + i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_STOP, + &rx_data); + } else if (rx_status == I2C_SLAVE_RX_FIFO_EMPTY) { + iproc_i2c->rx_start_rcvd = false; + iproc_i2c->slave_read_complete = true; + break; + } + + rx_bytes++; + } +} + +static void slave_rx_tasklet_fn(unsigned long data) +{ + struct bcm_iproc_i2c_dev *iproc_i2c = (struct bcm_iproc_i2c_dev *)data; + u32 int_clr; + + bcm_iproc_i2c_slave_read(iproc_i2c); + + /* clear pending IS_S_RX_EVENT_SHIFT interrupt */ + int_clr = BIT(IS_S_RX_EVENT_SHIFT); + + if (!iproc_i2c->slave_rx_only && iproc_i2c->slave_read_complete) { + /* + * In case of single byte master-read request, + * IS_S_TX_UNDERRUN_SHIFT event is generated before + * IS_S_START_BUSY_SHIFT event. Hence start slave data send + * from first IS_S_TX_UNDERRUN_SHIFT event. + * + * This means don't send any data from slave when + * IS_S_RD_EVENT_SHIFT event is generated else it will increment + * eeprom or other backend slave driver read pointer twice. + */ + iproc_i2c->tx_underrun = 0; + iproc_i2c->slave_int_mask |= BIT(IE_S_TX_UNDERRUN_SHIFT); + + /* clear IS_S_RD_EVENT_SHIFT interrupt */ + int_clr |= BIT(IS_S_RD_EVENT_SHIFT); + } + + /* clear slave interrupt */ + iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, int_clr); + /* enable slave interrupts */ + iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, iproc_i2c->slave_int_mask); +} + +static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c, + u32 status) +{ + u32 val; + u8 value; + + + if (status & BIT(IS_S_TX_UNDERRUN_SHIFT)) { + iproc_i2c->tx_underrun++; + if (iproc_i2c->tx_underrun == 1) + /* Start of SMBUS for Master Read */ + i2c_slave_event(iproc_i2c->slave, + I2C_SLAVE_READ_REQUESTED, + &value); + else + /* Master read other than start */ + i2c_slave_event(iproc_i2c->slave, + I2C_SLAVE_READ_PROCESSED, + &value); + + iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, value); + /* start transfer */ + val = BIT(S_CMD_START_BUSY_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val); + + /* clear interrupt */ + iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, + BIT(IS_S_TX_UNDERRUN_SHIFT)); + } + + /* Stop received from master in case of master read transaction */ + if (status & BIT(IS_S_START_BUSY_SHIFT)) { + /* + * Disable interrupt for TX FIFO becomes empty and + * less than PKT_LENGTH bytes were output on the SMBUS + */ + iproc_i2c->slave_int_mask &= ~BIT(IE_S_TX_UNDERRUN_SHIFT); + val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET); + val &= ~BIT(IE_S_TX_UNDERRUN_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val); + + /* End of SMBUS for Master Read */ + val = BIT(S_TX_WR_STATUS_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, val); + + val = BIT(S_CMD_START_BUSY_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val); + + /* flush TX FIFOs */ + val = iproc_i2c_rd_reg(iproc_i2c, S_FIFO_CTRL_OFFSET); + val |= (BIT(S_FIFO_TX_FLUSH_SHIFT)); + iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, val); + + i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_STOP, &value); + + /* clear interrupt */ + iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, + BIT(IS_S_START_BUSY_SHIFT)); + } + + /* if the controller has been reset, immediately return from the ISR */ + if (bcm_iproc_i2c_check_slave_status(iproc_i2c, status)) + return true; + + /* + * Slave events in case of master-write, master-write-read and, + * master-read + * + * Master-write : only IS_S_RX_EVENT_SHIFT event + * Master-write-read: both IS_S_RX_EVENT_SHIFT and IS_S_RD_EVENT_SHIFT + * events + * Master-read : both IS_S_RX_EVENT_SHIFT and IS_S_RD_EVENT_SHIFT + * events or only IS_S_RD_EVENT_SHIFT + * + * iproc has a slave rx fifo size of 64 bytes. Rx fifo full interrupt + * (IS_S_RX_FIFO_FULL_SHIFT) will be generated when RX fifo becomes + * full. This can happen if Master issues write requests of more than + * 64 bytes. + */ + if (status & BIT(IS_S_RX_EVENT_SHIFT) || + status & BIT(IS_S_RD_EVENT_SHIFT) || + status & BIT(IS_S_RX_FIFO_FULL_SHIFT)) { + /* disable slave interrupts */ + val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET); + val &= ~iproc_i2c->slave_int_mask; + iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val); + + if (status & BIT(IS_S_RD_EVENT_SHIFT)) + /* Master-write-read request */ + iproc_i2c->slave_rx_only = false; + else + /* Master-write request only */ + iproc_i2c->slave_rx_only = true; + + /* schedule tasklet to read data later */ + tasklet_schedule(&iproc_i2c->slave_rx_tasklet); + + /* clear IS_S_RX_FIFO_FULL_SHIFT interrupt */ + if (status & BIT(IS_S_RX_FIFO_FULL_SHIFT)) { + val = BIT(IS_S_RX_FIFO_FULL_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, val); + } + } + + return true; +} + +static void bcm_iproc_i2c_read_valid_bytes(struct bcm_iproc_i2c_dev *iproc_i2c) +{ + struct i2c_msg *msg = iproc_i2c->msg; + uint32_t val; + + /* Read valid data from RX FIFO */ + while (iproc_i2c->rx_bytes < msg->len) { + val = iproc_i2c_rd_reg(iproc_i2c, M_RX_OFFSET); + + /* rx fifo empty */ + if (!((val >> M_RX_STATUS_SHIFT) & M_RX_STATUS_MASK)) + break; + + msg->buf[iproc_i2c->rx_bytes] = + (val >> M_RX_DATA_SHIFT) & M_RX_DATA_MASK; + iproc_i2c->rx_bytes++; + } +} + +static void bcm_iproc_i2c_send(struct bcm_iproc_i2c_dev *iproc_i2c) +{ + struct i2c_msg *msg = iproc_i2c->msg; + unsigned int tx_bytes = msg->len - iproc_i2c->tx_bytes; + unsigned int i; + u32 val; + + /* can only fill up to the FIFO size */ + tx_bytes = min_t(unsigned int, tx_bytes, M_TX_RX_FIFO_SIZE); + for (i = 0; i < tx_bytes; i++) { + /* start from where we left over */ + unsigned int idx = iproc_i2c->tx_bytes + i; + + val = msg->buf[idx]; + + /* mark the last byte */ + if (idx == msg->len - 1) { + val |= BIT(M_TX_WR_STATUS_SHIFT); + + if (iproc_i2c->irq) { + u32 tmp; + + /* + * Since this is the last byte, we should now + * disable TX FIFO underrun interrupt + */ + tmp = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET); + tmp &= ~BIT(IE_M_TX_UNDERRUN_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, + tmp); + } + } + + /* load data into TX FIFO */ + iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val); + } + + /* update number of transferred bytes */ + iproc_i2c->tx_bytes += tx_bytes; +} + +static void bcm_iproc_i2c_read(struct bcm_iproc_i2c_dev *iproc_i2c) +{ + struct i2c_msg *msg = iproc_i2c->msg; + u32 bytes_left, val; + + bcm_iproc_i2c_read_valid_bytes(iproc_i2c); + bytes_left = msg->len - iproc_i2c->rx_bytes; + if (bytes_left == 0) { + if (iproc_i2c->irq) { + /* finished reading all data, disable rx thld event */ + val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET); + val &= ~BIT(IS_M_RX_THLD_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val); + } + } else if (bytes_left < iproc_i2c->thld_bytes) { + /* set bytes left as threshold */ + val = iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET); + val &= ~(M_FIFO_RX_THLD_MASK << M_FIFO_RX_THLD_SHIFT); + val |= (bytes_left << M_FIFO_RX_THLD_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val); + iproc_i2c->thld_bytes = bytes_left; + } + /* + * bytes_left >= iproc_i2c->thld_bytes, + * hence no need to change the THRESHOLD SET. + * It will remain as iproc_i2c->thld_bytes itself + */ +} + +static void bcm_iproc_i2c_process_m_event(struct bcm_iproc_i2c_dev *iproc_i2c, + u32 status) +{ + /* TX FIFO is empty and we have more data to send */ + if (status & BIT(IS_M_TX_UNDERRUN_SHIFT)) + bcm_iproc_i2c_send(iproc_i2c); + + /* RX FIFO threshold is reached and data needs to be read out */ + if (status & BIT(IS_M_RX_THLD_SHIFT)) + bcm_iproc_i2c_read(iproc_i2c); + + /* transfer is done */ + if (status & BIT(IS_M_START_BUSY_SHIFT)) { + iproc_i2c->xfer_is_done = 1; + if (iproc_i2c->irq) + complete(&iproc_i2c->done); + } +} + +static irqreturn_t bcm_iproc_i2c_isr(int irq, void *data) +{ + struct bcm_iproc_i2c_dev *iproc_i2c = data; + u32 slave_status; + u32 status; + bool ret; + + status = iproc_i2c_rd_reg(iproc_i2c, IS_OFFSET); + /* process only slave interrupt which are enabled */ + slave_status = status & iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET) & + ISR_MASK_SLAVE; + + if (slave_status) { + ret = bcm_iproc_i2c_slave_isr(iproc_i2c, slave_status); + if (ret) + return IRQ_HANDLED; + else + return IRQ_NONE; + } + + status &= ISR_MASK; + if (!status) + return IRQ_NONE; + + /* process all master based events */ + bcm_iproc_i2c_process_m_event(iproc_i2c, status); + iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status); + + return IRQ_HANDLED; +} + +static int bcm_iproc_i2c_init(struct bcm_iproc_i2c_dev *iproc_i2c) +{ + u32 val; + + /* put controller in reset */ + val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET); + val |= BIT(CFG_RESET_SHIFT); + val &= ~(BIT(CFG_EN_SHIFT)); + iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val); + + /* wait 100 usec per spec */ + udelay(100); + + /* bring controller out of reset */ + val &= ~(BIT(CFG_RESET_SHIFT)); + iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val); + + /* flush TX/RX FIFOs and set RX FIFO threshold to zero */ + val = (BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT)); + iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val); + /* disable all interrupts */ + val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET); + val &= ~(IE_M_ALL_INTERRUPT_MASK << + IE_M_ALL_INTERRUPT_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val); + + /* clear all pending interrupts */ + iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, 0xffffffff); + + return 0; +} + +static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c, + bool enable) +{ + u32 val; + + val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET); + if (enable) + val |= BIT(CFG_EN_SHIFT); + else + val &= ~BIT(CFG_EN_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val); +} + +static int bcm_iproc_i2c_check_status(struct bcm_iproc_i2c_dev *iproc_i2c, + struct i2c_msg *msg) +{ + u32 val; + + val = iproc_i2c_rd_reg(iproc_i2c, M_CMD_OFFSET); + val = (val >> M_CMD_STATUS_SHIFT) & M_CMD_STATUS_MASK; + + switch (val) { + case M_CMD_STATUS_SUCCESS: + return 0; + + case M_CMD_STATUS_LOST_ARB: + dev_dbg(iproc_i2c->device, "lost bus arbitration\n"); + return -EAGAIN; + + case M_CMD_STATUS_NACK_ADDR: + dev_dbg(iproc_i2c->device, "NAK addr:0x%02x\n", msg->addr); + return -ENXIO; + + case M_CMD_STATUS_NACK_DATA: + dev_dbg(iproc_i2c->device, "NAK data\n"); + return -ENXIO; + + case M_CMD_STATUS_TIMEOUT: + dev_dbg(iproc_i2c->device, "bus timeout\n"); + return -ETIMEDOUT; + + case M_CMD_STATUS_FIFO_UNDERRUN: + dev_dbg(iproc_i2c->device, "FIFO under-run\n"); + return -ENXIO; + + case M_CMD_STATUS_RX_FIFO_FULL: + dev_dbg(iproc_i2c->device, "RX FIFO full\n"); + return -ETIMEDOUT; + + default: + dev_dbg(iproc_i2c->device, "unknown error code=%d\n", val); + + /* re-initialize i2c for recovery */ + bcm_iproc_i2c_enable_disable(iproc_i2c, false); + bcm_iproc_i2c_init(iproc_i2c); + bcm_iproc_i2c_enable_disable(iproc_i2c, true); + + return -EIO; + } +} + +static int bcm_iproc_i2c_xfer_wait(struct bcm_iproc_i2c_dev *iproc_i2c, + struct i2c_msg *msg, + u32 cmd) +{ + unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT_MSEC); + u32 val, status; + int ret; + + iproc_i2c_wr_reg(iproc_i2c, M_CMD_OFFSET, cmd); + + if (iproc_i2c->irq) { + time_left = wait_for_completion_timeout(&iproc_i2c->done, + time_left); + /* disable all interrupts */ + iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0); + /* read it back to flush the write */ + iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET); + /* make sure the interrupt handler isn't running */ + synchronize_irq(iproc_i2c->irq); + + } else { /* polling mode */ + unsigned long timeout = jiffies + time_left; + + do { + status = iproc_i2c_rd_reg(iproc_i2c, + IS_OFFSET) & ISR_MASK; + bcm_iproc_i2c_process_m_event(iproc_i2c, status); + iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status); + + if (time_after(jiffies, timeout)) { + time_left = 0; + break; + } + + cpu_relax(); + cond_resched(); + } while (!iproc_i2c->xfer_is_done); + } + + if (!time_left && !iproc_i2c->xfer_is_done) { + dev_err(iproc_i2c->device, "transaction timed out\n"); + + /* flush both TX/RX FIFOs */ + val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val); + return -ETIMEDOUT; + } + + ret = bcm_iproc_i2c_check_status(iproc_i2c, msg); + if (ret) { + /* flush both TX/RX FIFOs */ + val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val); + return ret; + } + + return 0; +} + +/* + * If 'process_call' is true, then this is a multi-msg transfer that requires + * a repeated start between the messages. + * More specifically, it must be a write (reg) followed by a read (data). + * The i2c quirks are set to enforce this rule. + */ +static int bcm_iproc_i2c_xfer_internal(struct bcm_iproc_i2c_dev *iproc_i2c, + struct i2c_msg *msgs, bool process_call) +{ + int i; + u8 addr; + u32 val, tmp, val_intr_en; + unsigned int tx_bytes; + struct i2c_msg *msg = &msgs[0]; + + /* check if bus is busy */ + if (!!(iproc_i2c_rd_reg(iproc_i2c, + M_CMD_OFFSET) & BIT(M_CMD_START_BUSY_SHIFT))) { + dev_warn(iproc_i2c->device, "bus is busy\n"); + return -EBUSY; + } + + iproc_i2c->msg = msg; + + /* format and load slave address into the TX FIFO */ + addr = i2c_8bit_addr_from_msg(msg); + iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, addr); + + /* + * For a write transaction, load data into the TX FIFO. Only allow + * loading up to TX FIFO size - 1 bytes of data since the first byte + * has been used up by the slave address + */ + tx_bytes = min_t(unsigned int, msg->len, M_TX_RX_FIFO_SIZE - 1); + if (!(msg->flags & I2C_M_RD)) { + for (i = 0; i < tx_bytes; i++) { + val = msg->buf[i]; + + /* mark the last byte */ + if (!process_call && (i == msg->len - 1)) + val |= BIT(M_TX_WR_STATUS_SHIFT); + + iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val); + } + iproc_i2c->tx_bytes = tx_bytes; + } + + /* Process the read message if this is process call */ + if (process_call) { + msg++; + iproc_i2c->msg = msg; /* point to second msg */ + + /* + * The last byte to be sent out should be a slave + * address with read operation + */ + addr = i2c_8bit_addr_from_msg(msg); + /* mark it the last byte out */ + val = addr | BIT(M_TX_WR_STATUS_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val); + } + + /* mark as incomplete before starting the transaction */ + if (iproc_i2c->irq) + reinit_completion(&iproc_i2c->done); + + iproc_i2c->xfer_is_done = 0; + + /* + * Enable the "start busy" interrupt, which will be triggered after the + * transaction is done, i.e., the internal start_busy bit, transitions + * from 1 to 0. + */ + val_intr_en = BIT(IE_M_START_BUSY_SHIFT); + + /* + * If TX data size is larger than the TX FIFO, need to enable TX + * underrun interrupt, which will be triggerred when the TX FIFO is + * empty. When that happens we can then pump more data into the FIFO + */ + if (!process_call && !(msg->flags & I2C_M_RD) && + msg->len > iproc_i2c->tx_bytes) + val_intr_en |= BIT(IE_M_TX_UNDERRUN_SHIFT); + + /* + * Now we can activate the transfer. For a read operation, specify the + * number of bytes to read + */ + val = BIT(M_CMD_START_BUSY_SHIFT); + + if (msg->len == 0) { + /* SMBUS QUICK Command (Read/Write) */ + val |= (M_CMD_PROTOCOL_QUICK << M_CMD_PROTOCOL_SHIFT); + } else if (msg->flags & I2C_M_RD) { + u32 protocol; + + iproc_i2c->rx_bytes = 0; + if (msg->len > M_RX_FIFO_MAX_THLD_VALUE) + iproc_i2c->thld_bytes = M_RX_FIFO_THLD_VALUE; + else + iproc_i2c->thld_bytes = msg->len; + + /* set threshold value */ + tmp = iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET); + tmp &= ~(M_FIFO_RX_THLD_MASK << M_FIFO_RX_THLD_SHIFT); + tmp |= iproc_i2c->thld_bytes << M_FIFO_RX_THLD_SHIFT; + iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, tmp); + + /* enable the RX threshold interrupt */ + val_intr_en |= BIT(IE_M_RX_THLD_SHIFT); + + protocol = process_call ? + M_CMD_PROTOCOL_PROCESS : M_CMD_PROTOCOL_BLK_RD; + + val |= (protocol << M_CMD_PROTOCOL_SHIFT) | + (msg->len << M_CMD_RD_CNT_SHIFT); + } else { + val |= (M_CMD_PROTOCOL_BLK_WR << M_CMD_PROTOCOL_SHIFT); + } + + if (iproc_i2c->irq) + iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val_intr_en); + + return bcm_iproc_i2c_xfer_wait(iproc_i2c, msg, val); +} + +static int bcm_iproc_i2c_xfer(struct i2c_adapter *adapter, + struct i2c_msg msgs[], int num) +{ + struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adapter); + bool process_call = false; + int ret; + + if (num == 2) { + /* Repeated start, use process call */ + process_call = true; + if (msgs[1].flags & I2C_M_NOSTART) { + dev_err(iproc_i2c->device, "Invalid repeated start\n"); + return -EOPNOTSUPP; + } + } + + ret = bcm_iproc_i2c_xfer_internal(iproc_i2c, msgs, process_call); + if (ret) { + dev_dbg(iproc_i2c->device, "xfer failed\n"); + return ret; + } + + return num; +} + +static uint32_t bcm_iproc_i2c_functionality(struct i2c_adapter *adap) +{ + u32 val; + + val = I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; + + if (adap->algo->reg_slave) + val |= I2C_FUNC_SLAVE; + + return val; +} + +static struct i2c_algorithm bcm_iproc_algo = { + .master_xfer = bcm_iproc_i2c_xfer, + .functionality = bcm_iproc_i2c_functionality, + .reg_slave = bcm_iproc_i2c_reg_slave, + .unreg_slave = bcm_iproc_i2c_unreg_slave, +}; + +static const struct i2c_adapter_quirks bcm_iproc_i2c_quirks = { + .flags = I2C_AQ_COMB_WRITE_THEN_READ, + .max_comb_1st_msg_len = M_TX_RX_FIFO_SIZE, + .max_read_len = M_RX_MAX_READ_LEN, +}; + +static int bcm_iproc_i2c_cfg_speed(struct bcm_iproc_i2c_dev *iproc_i2c) +{ + unsigned int bus_speed; + u32 val; + int ret = of_property_read_u32(iproc_i2c->device->of_node, + "clock-frequency", &bus_speed); + if (ret < 0) { + dev_info(iproc_i2c->device, + "unable to interpret clock-frequency DT property\n"); + bus_speed = I2C_MAX_STANDARD_MODE_FREQ; + } + + if (bus_speed < I2C_MAX_STANDARD_MODE_FREQ) { + dev_err(iproc_i2c->device, "%d Hz bus speed not supported\n", + bus_speed); + dev_err(iproc_i2c->device, + "valid speeds are 100khz and 400khz\n"); + return -EINVAL; + } else if (bus_speed < I2C_MAX_FAST_MODE_FREQ) { + bus_speed = I2C_MAX_STANDARD_MODE_FREQ; + } else { + bus_speed = I2C_MAX_FAST_MODE_FREQ; + } + + iproc_i2c->bus_speed = bus_speed; + val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET); + val &= ~BIT(TIM_CFG_MODE_400_SHIFT); + val |= (bus_speed == I2C_MAX_FAST_MODE_FREQ) << TIM_CFG_MODE_400_SHIFT; + iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val); + + dev_info(iproc_i2c->device, "bus set to %u Hz\n", bus_speed); + + return 0; +} + +static int bcm_iproc_i2c_probe(struct platform_device *pdev) +{ + int irq, ret = 0; + struct bcm_iproc_i2c_dev *iproc_i2c; + struct i2c_adapter *adap; + + iproc_i2c = devm_kzalloc(&pdev->dev, sizeof(*iproc_i2c), + GFP_KERNEL); + if (!iproc_i2c) + return -ENOMEM; + + platform_set_drvdata(pdev, iproc_i2c); + iproc_i2c->device = &pdev->dev; + iproc_i2c->type = + (enum bcm_iproc_i2c_type)of_device_get_match_data(&pdev->dev); + init_completion(&iproc_i2c->done); + + iproc_i2c->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(iproc_i2c->base)) + return PTR_ERR(iproc_i2c->base); + + if (iproc_i2c->type == IPROC_I2C_NIC) { + iproc_i2c->idm_base = devm_platform_ioremap_resource(pdev, 1); + if (IS_ERR(iproc_i2c->idm_base)) + return PTR_ERR(iproc_i2c->idm_base); + + ret = of_property_read_u32(iproc_i2c->device->of_node, + "brcm,ape-hsls-addr-mask", + &iproc_i2c->ape_addr_mask); + if (ret < 0) { + dev_err(iproc_i2c->device, + "'brcm,ape-hsls-addr-mask' missing\n"); + return -EINVAL; + } + + spin_lock_init(&iproc_i2c->idm_lock); + + /* no slave support */ + bcm_iproc_algo.reg_slave = NULL; + bcm_iproc_algo.unreg_slave = NULL; + } + + ret = bcm_iproc_i2c_init(iproc_i2c); + if (ret) + return ret; + + ret = bcm_iproc_i2c_cfg_speed(iproc_i2c); + if (ret) + return ret; + + irq = platform_get_irq(pdev, 0); + if (irq > 0) { + ret = devm_request_irq(iproc_i2c->device, irq, + bcm_iproc_i2c_isr, 0, pdev->name, + iproc_i2c); + if (ret < 0) { + dev_err(iproc_i2c->device, + "unable to request irq %i\n", irq); + return ret; + } + + iproc_i2c->irq = irq; + } else { + dev_warn(iproc_i2c->device, + "no irq resource, falling back to poll mode\n"); + } + + bcm_iproc_i2c_enable_disable(iproc_i2c, true); + + adap = &iproc_i2c->adapter; + i2c_set_adapdata(adap, iproc_i2c); + snprintf(adap->name, sizeof(adap->name), + "Broadcom iProc (%s)", + of_node_full_name(iproc_i2c->device->of_node)); + adap->algo = &bcm_iproc_algo; + adap->quirks = &bcm_iproc_i2c_quirks; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + + return i2c_add_adapter(adap); +} + +static void bcm_iproc_i2c_remove(struct platform_device *pdev) +{ + struct bcm_iproc_i2c_dev *iproc_i2c = platform_get_drvdata(pdev); + + if (iproc_i2c->irq) { + /* + * Make sure there's no pending interrupt when we remove the + * adapter + */ + iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0); + iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET); + synchronize_irq(iproc_i2c->irq); + } + + i2c_del_adapter(&iproc_i2c->adapter); + bcm_iproc_i2c_enable_disable(iproc_i2c, false); +} + +static int bcm_iproc_i2c_suspend(struct device *dev) +{ + struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev); + + if (iproc_i2c->irq) { + /* + * Make sure there's no pending interrupt when we go into + * suspend + */ + iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0); + iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET); + synchronize_irq(iproc_i2c->irq); + } + + /* now disable the controller */ + bcm_iproc_i2c_enable_disable(iproc_i2c, false); + + return 0; +} + +static int bcm_iproc_i2c_resume(struct device *dev) +{ + struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev); + int ret; + u32 val; + + /* + * Power domain could have been shut off completely in system deep + * sleep, so re-initialize the block here + */ + ret = bcm_iproc_i2c_init(iproc_i2c); + if (ret) + return ret; + + /* configure to the desired bus speed */ + val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET); + val &= ~BIT(TIM_CFG_MODE_400_SHIFT); + val |= (iproc_i2c->bus_speed == I2C_MAX_FAST_MODE_FREQ) << TIM_CFG_MODE_400_SHIFT; + iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val); + + bcm_iproc_i2c_enable_disable(iproc_i2c, true); + + return 0; +} + +static const struct dev_pm_ops bcm_iproc_i2c_pm_ops = { + .suspend_late = &bcm_iproc_i2c_suspend, + .resume_early = &bcm_iproc_i2c_resume +}; + +static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave) +{ + struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(slave->adapter); + + if (iproc_i2c->slave) + return -EBUSY; + + if (slave->flags & I2C_CLIENT_TEN) + return -EAFNOSUPPORT; + + iproc_i2c->slave = slave; + + tasklet_init(&iproc_i2c->slave_rx_tasklet, slave_rx_tasklet_fn, + (unsigned long)iproc_i2c); + + bcm_iproc_i2c_slave_init(iproc_i2c, false); + return 0; +} + +static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave) +{ + u32 tmp; + struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(slave->adapter); + + if (!iproc_i2c->slave) + return -EINVAL; + + disable_irq(iproc_i2c->irq); + + tasklet_kill(&iproc_i2c->slave_rx_tasklet); + + /* disable all slave interrupts */ + tmp = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET); + tmp &= ~(IE_S_ALL_INTERRUPT_MASK << + IE_S_ALL_INTERRUPT_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, tmp); + + /* Erase the slave address programmed */ + tmp = iproc_i2c_rd_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET); + tmp &= ~BIT(S_CFG_EN_NIC_SMB_ADDR3_SHIFT); + iproc_i2c_wr_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET, tmp); + + /* flush TX/RX FIFOs */ + tmp = (BIT(S_FIFO_RX_FLUSH_SHIFT) | BIT(S_FIFO_TX_FLUSH_SHIFT)); + iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, tmp); + + /* clear all pending slave interrupts */ + iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, ISR_MASK_SLAVE); + + iproc_i2c->slave = NULL; + + enable_irq(iproc_i2c->irq); + + return 0; +} + +static const struct of_device_id bcm_iproc_i2c_of_match[] = { + { + .compatible = "brcm,iproc-i2c", + .data = (int *)IPROC_I2C, + }, { + .compatible = "brcm,iproc-nic-i2c", + .data = (int *)IPROC_I2C_NIC, + }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, bcm_iproc_i2c_of_match); + +static struct platform_driver bcm_iproc_i2c_driver = { + .driver = { + .name = "bcm-iproc-i2c", + .of_match_table = bcm_iproc_i2c_of_match, + .pm = pm_sleep_ptr(&bcm_iproc_i2c_pm_ops), + }, + .probe = bcm_iproc_i2c_probe, + .remove_new = bcm_iproc_i2c_remove, +}; +module_platform_driver(bcm_iproc_i2c_driver); + +MODULE_AUTHOR("Ray Jui <rjui@broadcom.com>"); +MODULE_DESCRIPTION("Broadcom iProc I2C Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-bcm-kona.c b/drivers/i2c/busses/i2c-bcm-kona.c new file mode 100644 index 000000000..a57088ec2 --- /dev/null +++ b/drivers/i2c/busses/i2c-bcm-kona.c @@ -0,0 +1,887 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (C) 2013 Broadcom Corporation + +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/slab.h> + +/* Hardware register offsets and field defintions */ +#define CS_OFFSET 0x00000020 +#define CS_ACK_SHIFT 3 +#define CS_ACK_MASK 0x00000008 +#define CS_ACK_CMD_GEN_START 0x00000000 +#define CS_ACK_CMD_GEN_RESTART 0x00000001 +#define CS_CMD_SHIFT 1 +#define CS_CMD_CMD_NO_ACTION 0x00000000 +#define CS_CMD_CMD_START_RESTART 0x00000001 +#define CS_CMD_CMD_STOP 0x00000002 +#define CS_EN_SHIFT 0 +#define CS_EN_CMD_ENABLE_BSC 0x00000001 + +#define TIM_OFFSET 0x00000024 +#define TIM_PRESCALE_SHIFT 6 +#define TIM_P_SHIFT 3 +#define TIM_NO_DIV_SHIFT 2 +#define TIM_DIV_SHIFT 0 + +#define DAT_OFFSET 0x00000028 + +#define TOUT_OFFSET 0x0000002c + +#define TXFCR_OFFSET 0x0000003c +#define TXFCR_FIFO_FLUSH_MASK 0x00000080 +#define TXFCR_FIFO_EN_MASK 0x00000040 + +#define IER_OFFSET 0x00000044 +#define IER_READ_COMPLETE_INT_MASK 0x00000010 +#define IER_I2C_INT_EN_MASK 0x00000008 +#define IER_FIFO_INT_EN_MASK 0x00000002 +#define IER_NOACK_EN_MASK 0x00000001 + +#define ISR_OFFSET 0x00000048 +#define ISR_RESERVED_MASK 0xffffff60 +#define ISR_CMDBUSY_MASK 0x00000080 +#define ISR_READ_COMPLETE_MASK 0x00000010 +#define ISR_SES_DONE_MASK 0x00000008 +#define ISR_ERR_MASK 0x00000004 +#define ISR_TXFIFOEMPTY_MASK 0x00000002 +#define ISR_NOACK_MASK 0x00000001 + +#define CLKEN_OFFSET 0x0000004C +#define CLKEN_AUTOSENSE_OFF_MASK 0x00000080 +#define CLKEN_M_SHIFT 4 +#define CLKEN_N_SHIFT 1 +#define CLKEN_CLKEN_MASK 0x00000001 + +#define FIFO_STATUS_OFFSET 0x00000054 +#define FIFO_STATUS_RXFIFO_EMPTY_MASK 0x00000004 +#define FIFO_STATUS_TXFIFO_EMPTY_MASK 0x00000010 + +#define HSTIM_OFFSET 0x00000058 +#define HSTIM_HS_MODE_MASK 0x00008000 +#define HSTIM_HS_HOLD_SHIFT 10 +#define HSTIM_HS_HIGH_PHASE_SHIFT 5 +#define HSTIM_HS_SETUP_SHIFT 0 + +#define PADCTL_OFFSET 0x0000005c +#define PADCTL_PAD_OUT_EN_MASK 0x00000004 + +#define RXFCR_OFFSET 0x00000068 +#define RXFCR_NACK_EN_SHIFT 7 +#define RXFCR_READ_COUNT_SHIFT 0 +#define RXFIFORDOUT_OFFSET 0x0000006c + +/* Locally used constants */ +#define MAX_RX_FIFO_SIZE 64U /* bytes */ +#define MAX_TX_FIFO_SIZE 64U /* bytes */ + +#define STD_EXT_CLK_FREQ 13000000UL +#define HS_EXT_CLK_FREQ 104000000UL + +#define MASTERCODE 0x08 /* Mastercodes are 0000_1xxxb */ + +#define I2C_TIMEOUT 100 /* msecs */ + +/* Operations that can be commanded to the controller */ +enum bcm_kona_cmd_t { + BCM_CMD_NOACTION = 0, + BCM_CMD_START, + BCM_CMD_RESTART, + BCM_CMD_STOP, +}; + +enum bus_speed_index { + BCM_SPD_100K = 0, + BCM_SPD_400K, + BCM_SPD_1MHZ, +}; + +enum hs_bus_speed_index { + BCM_SPD_3P4MHZ = 0, +}; + +/* Internal divider settings for standard mode, fast mode and fast mode plus */ +struct bus_speed_cfg { + uint8_t time_m; /* Number of cycles for setup time */ + uint8_t time_n; /* Number of cycles for hold time */ + uint8_t prescale; /* Prescale divider */ + uint8_t time_p; /* Timing coefficient */ + uint8_t no_div; /* Disable clock divider */ + uint8_t time_div; /* Post-prescale divider */ +}; + +/* Internal divider settings for high-speed mode */ +struct hs_bus_speed_cfg { + uint8_t hs_hold; /* Number of clock cycles SCL stays low until + the end of bit period */ + uint8_t hs_high_phase; /* Number of clock cycles SCL stays high + before it falls */ + uint8_t hs_setup; /* Number of clock cycles SCL stays low + before it rises */ + uint8_t prescale; /* Prescale divider */ + uint8_t time_p; /* Timing coefficient */ + uint8_t no_div; /* Disable clock divider */ + uint8_t time_div; /* Post-prescale divider */ +}; + +static const struct bus_speed_cfg std_cfg_table[] = { + [BCM_SPD_100K] = {0x01, 0x01, 0x03, 0x06, 0x00, 0x02}, + [BCM_SPD_400K] = {0x05, 0x01, 0x03, 0x05, 0x01, 0x02}, + [BCM_SPD_1MHZ] = {0x01, 0x01, 0x03, 0x01, 0x01, 0x03}, +}; + +static const struct hs_bus_speed_cfg hs_cfg_table[] = { + [BCM_SPD_3P4MHZ] = {0x01, 0x08, 0x14, 0x00, 0x06, 0x01, 0x00}, +}; + +struct bcm_kona_i2c_dev { + struct device *device; + + void __iomem *base; + int irq; + struct clk *external_clk; + + struct i2c_adapter adapter; + + struct completion done; + + const struct bus_speed_cfg *std_cfg; + const struct hs_bus_speed_cfg *hs_cfg; +}; + +static void bcm_kona_i2c_send_cmd_to_ctrl(struct bcm_kona_i2c_dev *dev, + enum bcm_kona_cmd_t cmd) +{ + dev_dbg(dev->device, "%s, %d\n", __func__, cmd); + + switch (cmd) { + case BCM_CMD_NOACTION: + writel((CS_CMD_CMD_NO_ACTION << CS_CMD_SHIFT) | + (CS_EN_CMD_ENABLE_BSC << CS_EN_SHIFT), + dev->base + CS_OFFSET); + break; + + case BCM_CMD_START: + writel((CS_ACK_CMD_GEN_START << CS_ACK_SHIFT) | + (CS_CMD_CMD_START_RESTART << CS_CMD_SHIFT) | + (CS_EN_CMD_ENABLE_BSC << CS_EN_SHIFT), + dev->base + CS_OFFSET); + break; + + case BCM_CMD_RESTART: + writel((CS_ACK_CMD_GEN_RESTART << CS_ACK_SHIFT) | + (CS_CMD_CMD_START_RESTART << CS_CMD_SHIFT) | + (CS_EN_CMD_ENABLE_BSC << CS_EN_SHIFT), + dev->base + CS_OFFSET); + break; + + case BCM_CMD_STOP: + writel((CS_CMD_CMD_STOP << CS_CMD_SHIFT) | + (CS_EN_CMD_ENABLE_BSC << CS_EN_SHIFT), + dev->base + CS_OFFSET); + break; + + default: + dev_err(dev->device, "Unknown command %d\n", cmd); + } +} + +static void bcm_kona_i2c_enable_clock(struct bcm_kona_i2c_dev *dev) +{ + writel(readl(dev->base + CLKEN_OFFSET) | CLKEN_CLKEN_MASK, + dev->base + CLKEN_OFFSET); +} + +static void bcm_kona_i2c_disable_clock(struct bcm_kona_i2c_dev *dev) +{ + writel(readl(dev->base + CLKEN_OFFSET) & ~CLKEN_CLKEN_MASK, + dev->base + CLKEN_OFFSET); +} + +static irqreturn_t bcm_kona_i2c_isr(int irq, void *devid) +{ + struct bcm_kona_i2c_dev *dev = devid; + uint32_t status = readl(dev->base + ISR_OFFSET); + + if ((status & ~ISR_RESERVED_MASK) == 0) + return IRQ_NONE; + + /* Must flush the TX FIFO when NAK detected */ + if (status & ISR_NOACK_MASK) + writel(TXFCR_FIFO_FLUSH_MASK | TXFCR_FIFO_EN_MASK, + dev->base + TXFCR_OFFSET); + + writel(status & ~ISR_RESERVED_MASK, dev->base + ISR_OFFSET); + complete(&dev->done); + + return IRQ_HANDLED; +} + +/* Wait for ISR_CMDBUSY_MASK to go low before writing to CS, DAT, or RCD */ +static int bcm_kona_i2c_wait_if_busy(struct bcm_kona_i2c_dev *dev) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(I2C_TIMEOUT); + + while (readl(dev->base + ISR_OFFSET) & ISR_CMDBUSY_MASK) + if (time_after(jiffies, timeout)) { + dev_err(dev->device, "CMDBUSY timeout\n"); + return -ETIMEDOUT; + } + + return 0; +} + +/* Send command to I2C bus */ +static int bcm_kona_send_i2c_cmd(struct bcm_kona_i2c_dev *dev, + enum bcm_kona_cmd_t cmd) +{ + int rc; + unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT); + + /* Make sure the hardware is ready */ + rc = bcm_kona_i2c_wait_if_busy(dev); + if (rc < 0) + return rc; + + /* Unmask the session done interrupt */ + writel(IER_I2C_INT_EN_MASK, dev->base + IER_OFFSET); + + /* Mark as incomplete before sending the command */ + reinit_completion(&dev->done); + + /* Send the command */ + bcm_kona_i2c_send_cmd_to_ctrl(dev, cmd); + + /* Wait for transaction to finish or timeout */ + time_left = wait_for_completion_timeout(&dev->done, time_left); + + /* Mask all interrupts */ + writel(0, dev->base + IER_OFFSET); + + if (!time_left) { + dev_err(dev->device, "controller timed out\n"); + rc = -ETIMEDOUT; + } + + /* Clear command */ + bcm_kona_i2c_send_cmd_to_ctrl(dev, BCM_CMD_NOACTION); + + return rc; +} + +/* Read a single RX FIFO worth of data from the i2c bus */ +static int bcm_kona_i2c_read_fifo_single(struct bcm_kona_i2c_dev *dev, + uint8_t *buf, unsigned int len, + unsigned int last_byte_nak) +{ + unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT); + + /* Mark as incomplete before starting the RX FIFO */ + reinit_completion(&dev->done); + + /* Unmask the read complete interrupt */ + writel(IER_READ_COMPLETE_INT_MASK, dev->base + IER_OFFSET); + + /* Start the RX FIFO */ + writel((last_byte_nak << RXFCR_NACK_EN_SHIFT) | + (len << RXFCR_READ_COUNT_SHIFT), + dev->base + RXFCR_OFFSET); + + /* Wait for FIFO read to complete */ + time_left = wait_for_completion_timeout(&dev->done, time_left); + + /* Mask all interrupts */ + writel(0, dev->base + IER_OFFSET); + + if (!time_left) { + dev_err(dev->device, "RX FIFO time out\n"); + return -EREMOTEIO; + } + + /* Read data from FIFO */ + for (; len > 0; len--, buf++) + *buf = readl(dev->base + RXFIFORDOUT_OFFSET); + + return 0; +} + +/* Read any amount of data using the RX FIFO from the i2c bus */ +static int bcm_kona_i2c_read_fifo(struct bcm_kona_i2c_dev *dev, + struct i2c_msg *msg) +{ + unsigned int bytes_to_read = MAX_RX_FIFO_SIZE; + unsigned int last_byte_nak = 0; + unsigned int bytes_read = 0; + int rc; + + uint8_t *tmp_buf = msg->buf; + + while (bytes_read < msg->len) { + if (msg->len - bytes_read <= MAX_RX_FIFO_SIZE) { + last_byte_nak = 1; /* NAK last byte of transfer */ + bytes_to_read = msg->len - bytes_read; + } + + rc = bcm_kona_i2c_read_fifo_single(dev, tmp_buf, bytes_to_read, + last_byte_nak); + if (rc < 0) + return -EREMOTEIO; + + bytes_read += bytes_to_read; + tmp_buf += bytes_to_read; + } + + return 0; +} + +/* Write a single byte of data to the i2c bus */ +static int bcm_kona_i2c_write_byte(struct bcm_kona_i2c_dev *dev, uint8_t data, + unsigned int nak_expected) +{ + int rc; + unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT); + unsigned int nak_received; + + /* Make sure the hardware is ready */ + rc = bcm_kona_i2c_wait_if_busy(dev); + if (rc < 0) + return rc; + + /* Clear pending session done interrupt */ + writel(ISR_SES_DONE_MASK, dev->base + ISR_OFFSET); + + /* Unmask the session done interrupt */ + writel(IER_I2C_INT_EN_MASK, dev->base + IER_OFFSET); + + /* Mark as incomplete before sending the data */ + reinit_completion(&dev->done); + + /* Send one byte of data */ + writel(data, dev->base + DAT_OFFSET); + + /* Wait for byte to be written */ + time_left = wait_for_completion_timeout(&dev->done, time_left); + + /* Mask all interrupts */ + writel(0, dev->base + IER_OFFSET); + + if (!time_left) { + dev_dbg(dev->device, "controller timed out\n"); + return -ETIMEDOUT; + } + + nak_received = readl(dev->base + CS_OFFSET) & CS_ACK_MASK ? 1 : 0; + + if (nak_received ^ nak_expected) { + dev_dbg(dev->device, "unexpected NAK/ACK\n"); + return -EREMOTEIO; + } + + return 0; +} + +/* Write a single TX FIFO worth of data to the i2c bus */ +static int bcm_kona_i2c_write_fifo_single(struct bcm_kona_i2c_dev *dev, + uint8_t *buf, unsigned int len) +{ + int k; + unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT); + unsigned int fifo_status; + + /* Mark as incomplete before sending data to the TX FIFO */ + reinit_completion(&dev->done); + + /* Unmask the fifo empty and nak interrupt */ + writel(IER_FIFO_INT_EN_MASK | IER_NOACK_EN_MASK, + dev->base + IER_OFFSET); + + /* Disable IRQ to load a FIFO worth of data without interruption */ + disable_irq(dev->irq); + + /* Write data into FIFO */ + for (k = 0; k < len; k++) + writel(buf[k], (dev->base + DAT_OFFSET)); + + /* Enable IRQ now that data has been loaded */ + enable_irq(dev->irq); + + /* Wait for FIFO to empty */ + do { + time_left = wait_for_completion_timeout(&dev->done, time_left); + fifo_status = readl(dev->base + FIFO_STATUS_OFFSET); + } while (time_left && !(fifo_status & FIFO_STATUS_TXFIFO_EMPTY_MASK)); + + /* Mask all interrupts */ + writel(0, dev->base + IER_OFFSET); + + /* Check if there was a NAK */ + if (readl(dev->base + CS_OFFSET) & CS_ACK_MASK) { + dev_err(dev->device, "unexpected NAK\n"); + return -EREMOTEIO; + } + + /* Check if a timeout occured */ + if (!time_left) { + dev_err(dev->device, "completion timed out\n"); + return -EREMOTEIO; + } + + return 0; +} + + +/* Write any amount of data using TX FIFO to the i2c bus */ +static int bcm_kona_i2c_write_fifo(struct bcm_kona_i2c_dev *dev, + struct i2c_msg *msg) +{ + unsigned int bytes_to_write = MAX_TX_FIFO_SIZE; + unsigned int bytes_written = 0; + int rc; + + uint8_t *tmp_buf = msg->buf; + + while (bytes_written < msg->len) { + if (msg->len - bytes_written <= MAX_TX_FIFO_SIZE) + bytes_to_write = msg->len - bytes_written; + + rc = bcm_kona_i2c_write_fifo_single(dev, tmp_buf, + bytes_to_write); + if (rc < 0) + return -EREMOTEIO; + + bytes_written += bytes_to_write; + tmp_buf += bytes_to_write; + } + + return 0; +} + +/* Send i2c address */ +static int bcm_kona_i2c_do_addr(struct bcm_kona_i2c_dev *dev, + struct i2c_msg *msg) +{ + unsigned char addr; + + if (msg->flags & I2C_M_TEN) { + /* First byte is 11110XX0 where XX is upper 2 bits */ + addr = 0xF0 | ((msg->addr & 0x300) >> 7); + if (bcm_kona_i2c_write_byte(dev, addr, 0) < 0) + return -EREMOTEIO; + + /* Second byte is the remaining 8 bits */ + addr = msg->addr & 0xFF; + if (bcm_kona_i2c_write_byte(dev, addr, 0) < 0) + return -EREMOTEIO; + + if (msg->flags & I2C_M_RD) { + /* For read, send restart command */ + if (bcm_kona_send_i2c_cmd(dev, BCM_CMD_RESTART) < 0) + return -EREMOTEIO; + + /* Then re-send the first byte with the read bit set */ + addr = 0xF0 | ((msg->addr & 0x300) >> 7) | 0x01; + if (bcm_kona_i2c_write_byte(dev, addr, 0) < 0) + return -EREMOTEIO; + } + } else { + addr = i2c_8bit_addr_from_msg(msg); + + if (bcm_kona_i2c_write_byte(dev, addr, 0) < 0) + return -EREMOTEIO; + } + + return 0; +} + +static void bcm_kona_i2c_enable_autosense(struct bcm_kona_i2c_dev *dev) +{ + writel(readl(dev->base + CLKEN_OFFSET) & ~CLKEN_AUTOSENSE_OFF_MASK, + dev->base + CLKEN_OFFSET); +} + +static void bcm_kona_i2c_config_timing(struct bcm_kona_i2c_dev *dev) +{ + writel(readl(dev->base + HSTIM_OFFSET) & ~HSTIM_HS_MODE_MASK, + dev->base + HSTIM_OFFSET); + + writel((dev->std_cfg->prescale << TIM_PRESCALE_SHIFT) | + (dev->std_cfg->time_p << TIM_P_SHIFT) | + (dev->std_cfg->no_div << TIM_NO_DIV_SHIFT) | + (dev->std_cfg->time_div << TIM_DIV_SHIFT), + dev->base + TIM_OFFSET); + + writel((dev->std_cfg->time_m << CLKEN_M_SHIFT) | + (dev->std_cfg->time_n << CLKEN_N_SHIFT) | + CLKEN_CLKEN_MASK, + dev->base + CLKEN_OFFSET); +} + +static void bcm_kona_i2c_config_timing_hs(struct bcm_kona_i2c_dev *dev) +{ + writel((dev->hs_cfg->prescale << TIM_PRESCALE_SHIFT) | + (dev->hs_cfg->time_p << TIM_P_SHIFT) | + (dev->hs_cfg->no_div << TIM_NO_DIV_SHIFT) | + (dev->hs_cfg->time_div << TIM_DIV_SHIFT), + dev->base + TIM_OFFSET); + + writel((dev->hs_cfg->hs_hold << HSTIM_HS_HOLD_SHIFT) | + (dev->hs_cfg->hs_high_phase << HSTIM_HS_HIGH_PHASE_SHIFT) | + (dev->hs_cfg->hs_setup << HSTIM_HS_SETUP_SHIFT), + dev->base + HSTIM_OFFSET); + + writel(readl(dev->base + HSTIM_OFFSET) | HSTIM_HS_MODE_MASK, + dev->base + HSTIM_OFFSET); +} + +static int bcm_kona_i2c_switch_to_hs(struct bcm_kona_i2c_dev *dev) +{ + int rc; + + /* Send mastercode at standard speed */ + rc = bcm_kona_i2c_write_byte(dev, MASTERCODE, 1); + if (rc < 0) { + pr_err("High speed handshake failed\n"); + return rc; + } + + /* Configure external clock to higher frequency */ + rc = clk_set_rate(dev->external_clk, HS_EXT_CLK_FREQ); + if (rc) { + dev_err(dev->device, "%s: clk_set_rate returned %d\n", + __func__, rc); + return rc; + } + + /* Reconfigure internal dividers */ + bcm_kona_i2c_config_timing_hs(dev); + + /* Send a restart command */ + rc = bcm_kona_send_i2c_cmd(dev, BCM_CMD_RESTART); + if (rc < 0) + dev_err(dev->device, "High speed restart command failed\n"); + + return rc; +} + +static int bcm_kona_i2c_switch_to_std(struct bcm_kona_i2c_dev *dev) +{ + int rc; + + /* Reconfigure internal dividers */ + bcm_kona_i2c_config_timing(dev); + + /* Configure external clock to lower frequency */ + rc = clk_set_rate(dev->external_clk, STD_EXT_CLK_FREQ); + if (rc) { + dev_err(dev->device, "%s: clk_set_rate returned %d\n", + __func__, rc); + } + + return rc; +} + +/* Master transfer function */ +static int bcm_kona_i2c_xfer(struct i2c_adapter *adapter, + struct i2c_msg msgs[], int num) +{ + struct bcm_kona_i2c_dev *dev = i2c_get_adapdata(adapter); + struct i2c_msg *pmsg; + int rc = 0; + int i; + + rc = clk_prepare_enable(dev->external_clk); + if (rc) { + dev_err(dev->device, "%s: peri clock enable failed. err %d\n", + __func__, rc); + return rc; + } + + /* Enable pad output */ + writel(0, dev->base + PADCTL_OFFSET); + + /* Enable internal clocks */ + bcm_kona_i2c_enable_clock(dev); + + /* Send start command */ + rc = bcm_kona_send_i2c_cmd(dev, BCM_CMD_START); + if (rc < 0) { + dev_err(dev->device, "Start command failed rc = %d\n", rc); + goto xfer_disable_pad; + } + + /* Switch to high speed if applicable */ + if (dev->hs_cfg) { + rc = bcm_kona_i2c_switch_to_hs(dev); + if (rc < 0) + goto xfer_send_stop; + } + + /* Loop through all messages */ + for (i = 0; i < num; i++) { + pmsg = &msgs[i]; + + /* Send restart for subsequent messages */ + if ((i != 0) && ((pmsg->flags & I2C_M_NOSTART) == 0)) { + rc = bcm_kona_send_i2c_cmd(dev, BCM_CMD_RESTART); + if (rc < 0) { + dev_err(dev->device, + "restart cmd failed rc = %d\n", rc); + goto xfer_send_stop; + } + } + + /* Send slave address */ + if (!(pmsg->flags & I2C_M_NOSTART)) { + rc = bcm_kona_i2c_do_addr(dev, pmsg); + if (rc < 0) { + dev_err(dev->device, + "NAK from addr %2.2x msg#%d rc = %d\n", + pmsg->addr, i, rc); + goto xfer_send_stop; + } + } + + /* Perform data transfer */ + if (pmsg->flags & I2C_M_RD) { + rc = bcm_kona_i2c_read_fifo(dev, pmsg); + if (rc < 0) { + dev_err(dev->device, "read failure\n"); + goto xfer_send_stop; + } + } else { + rc = bcm_kona_i2c_write_fifo(dev, pmsg); + if (rc < 0) { + dev_err(dev->device, "write failure"); + goto xfer_send_stop; + } + } + } + + rc = num; + +xfer_send_stop: + /* Send a STOP command */ + bcm_kona_send_i2c_cmd(dev, BCM_CMD_STOP); + + /* Return from high speed if applicable */ + if (dev->hs_cfg) { + int hs_rc = bcm_kona_i2c_switch_to_std(dev); + + if (hs_rc) + rc = hs_rc; + } + +xfer_disable_pad: + /* Disable pad output */ + writel(PADCTL_PAD_OUT_EN_MASK, dev->base + PADCTL_OFFSET); + + /* Stop internal clock */ + bcm_kona_i2c_disable_clock(dev); + + clk_disable_unprepare(dev->external_clk); + + return rc; +} + +static uint32_t bcm_kona_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR | + I2C_FUNC_NOSTART; +} + +static const struct i2c_algorithm bcm_algo = { + .master_xfer = bcm_kona_i2c_xfer, + .functionality = bcm_kona_i2c_functionality, +}; + +static int bcm_kona_i2c_assign_bus_speed(struct bcm_kona_i2c_dev *dev) +{ + unsigned int bus_speed; + int ret = of_property_read_u32(dev->device->of_node, "clock-frequency", + &bus_speed); + if (ret < 0) { + dev_err(dev->device, "missing clock-frequency property\n"); + return -ENODEV; + } + + switch (bus_speed) { + case I2C_MAX_STANDARD_MODE_FREQ: + dev->std_cfg = &std_cfg_table[BCM_SPD_100K]; + break; + case I2C_MAX_FAST_MODE_FREQ: + dev->std_cfg = &std_cfg_table[BCM_SPD_400K]; + break; + case I2C_MAX_FAST_MODE_PLUS_FREQ: + dev->std_cfg = &std_cfg_table[BCM_SPD_1MHZ]; + break; + case I2C_MAX_HIGH_SPEED_MODE_FREQ: + /* Send mastercode at 100k */ + dev->std_cfg = &std_cfg_table[BCM_SPD_100K]; + dev->hs_cfg = &hs_cfg_table[BCM_SPD_3P4MHZ]; + break; + default: + pr_err("%d hz bus speed not supported\n", bus_speed); + pr_err("Valid speeds are 100khz, 400khz, 1mhz, and 3.4mhz\n"); + return -EINVAL; + } + + return 0; +} + +static int bcm_kona_i2c_probe(struct platform_device *pdev) +{ + int rc = 0; + struct bcm_kona_i2c_dev *dev; + struct i2c_adapter *adap; + + /* Allocate memory for private data structure */ + dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + + platform_set_drvdata(pdev, dev); + dev->device = &pdev->dev; + init_completion(&dev->done); + + /* Map hardware registers */ + dev->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(dev->base)) + return PTR_ERR(dev->base); + + /* Get and enable external clock */ + dev->external_clk = devm_clk_get(dev->device, NULL); + if (IS_ERR(dev->external_clk)) { + dev_err(dev->device, "couldn't get clock\n"); + return -ENODEV; + } + + rc = clk_set_rate(dev->external_clk, STD_EXT_CLK_FREQ); + if (rc) { + dev_err(dev->device, "%s: clk_set_rate returned %d\n", + __func__, rc); + return rc; + } + + rc = clk_prepare_enable(dev->external_clk); + if (rc) { + dev_err(dev->device, "couldn't enable clock\n"); + return rc; + } + + /* Parse bus speed */ + rc = bcm_kona_i2c_assign_bus_speed(dev); + if (rc) + goto probe_disable_clk; + + /* Enable internal clocks */ + bcm_kona_i2c_enable_clock(dev); + + /* Configure internal dividers */ + bcm_kona_i2c_config_timing(dev); + + /* Disable timeout */ + writel(0, dev->base + TOUT_OFFSET); + + /* Enable autosense */ + bcm_kona_i2c_enable_autosense(dev); + + /* Enable TX FIFO */ + writel(TXFCR_FIFO_FLUSH_MASK | TXFCR_FIFO_EN_MASK, + dev->base + TXFCR_OFFSET); + + /* Mask all interrupts */ + writel(0, dev->base + IER_OFFSET); + + /* Clear all pending interrupts */ + writel(ISR_CMDBUSY_MASK | + ISR_READ_COMPLETE_MASK | + ISR_SES_DONE_MASK | + ISR_ERR_MASK | + ISR_TXFIFOEMPTY_MASK | + ISR_NOACK_MASK, + dev->base + ISR_OFFSET); + + /* Get the interrupt number */ + dev->irq = platform_get_irq(pdev, 0); + if (dev->irq < 0) { + rc = dev->irq; + goto probe_disable_clk; + } + + /* register the ISR handler */ + rc = devm_request_irq(&pdev->dev, dev->irq, bcm_kona_i2c_isr, + IRQF_SHARED, pdev->name, dev); + if (rc) { + dev_err(dev->device, "failed to request irq %i\n", dev->irq); + goto probe_disable_clk; + } + + /* Enable the controller but leave it idle */ + bcm_kona_i2c_send_cmd_to_ctrl(dev, BCM_CMD_NOACTION); + + /* Disable pad output */ + writel(PADCTL_PAD_OUT_EN_MASK, dev->base + PADCTL_OFFSET); + + /* Disable internal clock */ + bcm_kona_i2c_disable_clock(dev); + + /* Disable external clock */ + clk_disable_unprepare(dev->external_clk); + + /* Add the i2c adapter */ + adap = &dev->adapter; + i2c_set_adapdata(adap, dev); + adap->owner = THIS_MODULE; + strscpy(adap->name, "Broadcom I2C adapter", sizeof(adap->name)); + adap->algo = &bcm_algo; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + + rc = i2c_add_adapter(adap); + if (rc) + return rc; + + dev_info(dev->device, "device registered successfully\n"); + + return 0; + +probe_disable_clk: + bcm_kona_i2c_disable_clock(dev); + clk_disable_unprepare(dev->external_clk); + + return rc; +} + +static void bcm_kona_i2c_remove(struct platform_device *pdev) +{ + struct bcm_kona_i2c_dev *dev = platform_get_drvdata(pdev); + + i2c_del_adapter(&dev->adapter); +} + +static const struct of_device_id bcm_kona_i2c_of_match[] = { + {.compatible = "brcm,kona-i2c",}, + {}, +}; +MODULE_DEVICE_TABLE(of, bcm_kona_i2c_of_match); + +static struct platform_driver bcm_kona_i2c_driver = { + .driver = { + .name = "bcm-kona-i2c", + .of_match_table = bcm_kona_i2c_of_match, + }, + .probe = bcm_kona_i2c_probe, + .remove_new = bcm_kona_i2c_remove, +}; +module_platform_driver(bcm_kona_i2c_driver); + +MODULE_AUTHOR("Tim Kryger <tkryger@broadcom.com>"); +MODULE_DESCRIPTION("Broadcom Kona I2C Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-bcm2835.c b/drivers/i2c/busses/i2c-bcm2835.c new file mode 100644 index 000000000..b92de1944 --- /dev/null +++ b/drivers/i2c/busses/i2c-bcm2835.c @@ -0,0 +1,535 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * BCM2835 master mode driver + */ + +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/completion.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#define BCM2835_I2C_C 0x0 +#define BCM2835_I2C_S 0x4 +#define BCM2835_I2C_DLEN 0x8 +#define BCM2835_I2C_A 0xc +#define BCM2835_I2C_FIFO 0x10 +#define BCM2835_I2C_DIV 0x14 +#define BCM2835_I2C_DEL 0x18 +/* + * 16-bit field for the number of SCL cycles to wait after rising SCL + * before deciding the slave is not responding. 0 disables the + * timeout detection. + */ +#define BCM2835_I2C_CLKT 0x1c + +#define BCM2835_I2C_C_READ BIT(0) +#define BCM2835_I2C_C_CLEAR BIT(4) /* bits 4 and 5 both clear */ +#define BCM2835_I2C_C_ST BIT(7) +#define BCM2835_I2C_C_INTD BIT(8) +#define BCM2835_I2C_C_INTT BIT(9) +#define BCM2835_I2C_C_INTR BIT(10) +#define BCM2835_I2C_C_I2CEN BIT(15) + +#define BCM2835_I2C_S_TA BIT(0) +#define BCM2835_I2C_S_DONE BIT(1) +#define BCM2835_I2C_S_TXW BIT(2) +#define BCM2835_I2C_S_RXR BIT(3) +#define BCM2835_I2C_S_TXD BIT(4) +#define BCM2835_I2C_S_RXD BIT(5) +#define BCM2835_I2C_S_TXE BIT(6) +#define BCM2835_I2C_S_RXF BIT(7) +#define BCM2835_I2C_S_ERR BIT(8) +#define BCM2835_I2C_S_CLKT BIT(9) +#define BCM2835_I2C_S_LEN BIT(10) /* Fake bit for SW error reporting */ + +#define BCM2835_I2C_FEDL_SHIFT 16 +#define BCM2835_I2C_REDL_SHIFT 0 + +#define BCM2835_I2C_CDIV_MIN 0x0002 +#define BCM2835_I2C_CDIV_MAX 0xFFFE + +struct bcm2835_i2c_dev { + struct device *dev; + void __iomem *regs; + int irq; + struct i2c_adapter adapter; + struct completion completion; + struct i2c_msg *curr_msg; + struct clk *bus_clk; + int num_msgs; + u32 msg_err; + u8 *msg_buf; + size_t msg_buf_remaining; +}; + +static inline void bcm2835_i2c_writel(struct bcm2835_i2c_dev *i2c_dev, + u32 reg, u32 val) +{ + writel(val, i2c_dev->regs + reg); +} + +static inline u32 bcm2835_i2c_readl(struct bcm2835_i2c_dev *i2c_dev, u32 reg) +{ + return readl(i2c_dev->regs + reg); +} + +#define to_clk_bcm2835_i2c(_hw) container_of(_hw, struct clk_bcm2835_i2c, hw) +struct clk_bcm2835_i2c { + struct clk_hw hw; + struct bcm2835_i2c_dev *i2c_dev; +}; + +static int clk_bcm2835_i2c_calc_divider(unsigned long rate, + unsigned long parent_rate) +{ + u32 divider = DIV_ROUND_UP(parent_rate, rate); + + /* + * Per the datasheet, the register is always interpreted as an even + * number, by rounding down. In other words, the LSB is ignored. So, + * if the LSB is set, increment the divider to avoid any issue. + */ + if (divider & 1) + divider++; + if ((divider < BCM2835_I2C_CDIV_MIN) || + (divider > BCM2835_I2C_CDIV_MAX)) + return -EINVAL; + + return divider; +} + +static int clk_bcm2835_i2c_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_bcm2835_i2c *div = to_clk_bcm2835_i2c(hw); + u32 redl, fedl; + u32 divider = clk_bcm2835_i2c_calc_divider(rate, parent_rate); + + if (divider == -EINVAL) + return -EINVAL; + + bcm2835_i2c_writel(div->i2c_dev, BCM2835_I2C_DIV, divider); + + /* + * Number of core clocks to wait after falling edge before + * outputting the next data bit. Note that both FEDL and REDL + * can't be greater than CDIV/2. + */ + fedl = max(divider / 16, 1u); + + /* + * Number of core clocks to wait after rising edge before + * sampling the next incoming data bit. + */ + redl = max(divider / 4, 1u); + + bcm2835_i2c_writel(div->i2c_dev, BCM2835_I2C_DEL, + (fedl << BCM2835_I2C_FEDL_SHIFT) | + (redl << BCM2835_I2C_REDL_SHIFT)); + return 0; +} + +static long clk_bcm2835_i2c_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + u32 divider = clk_bcm2835_i2c_calc_divider(rate, *parent_rate); + + return DIV_ROUND_UP(*parent_rate, divider); +} + +static unsigned long clk_bcm2835_i2c_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_bcm2835_i2c *div = to_clk_bcm2835_i2c(hw); + u32 divider = bcm2835_i2c_readl(div->i2c_dev, BCM2835_I2C_DIV); + + return DIV_ROUND_UP(parent_rate, divider); +} + +static const struct clk_ops clk_bcm2835_i2c_ops = { + .set_rate = clk_bcm2835_i2c_set_rate, + .round_rate = clk_bcm2835_i2c_round_rate, + .recalc_rate = clk_bcm2835_i2c_recalc_rate, +}; + +static struct clk *bcm2835_i2c_register_div(struct device *dev, + struct clk *mclk, + struct bcm2835_i2c_dev *i2c_dev) +{ + struct clk_init_data init; + struct clk_bcm2835_i2c *priv; + char name[32]; + const char *mclk_name; + + snprintf(name, sizeof(name), "%s_div", dev_name(dev)); + + mclk_name = __clk_get_name(mclk); + + init.ops = &clk_bcm2835_i2c_ops; + init.name = name; + init.parent_names = (const char* []) { mclk_name }; + init.num_parents = 1; + init.flags = 0; + + priv = devm_kzalloc(dev, sizeof(struct clk_bcm2835_i2c), GFP_KERNEL); + if (priv == NULL) + return ERR_PTR(-ENOMEM); + + priv->hw.init = &init; + priv->i2c_dev = i2c_dev; + + clk_hw_register_clkdev(&priv->hw, "div", dev_name(dev)); + return devm_clk_register(dev, &priv->hw); +} + +static void bcm2835_fill_txfifo(struct bcm2835_i2c_dev *i2c_dev) +{ + u32 val; + + while (i2c_dev->msg_buf_remaining) { + val = bcm2835_i2c_readl(i2c_dev, BCM2835_I2C_S); + if (!(val & BCM2835_I2C_S_TXD)) + break; + bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_FIFO, + *i2c_dev->msg_buf); + i2c_dev->msg_buf++; + i2c_dev->msg_buf_remaining--; + } +} + +static void bcm2835_drain_rxfifo(struct bcm2835_i2c_dev *i2c_dev) +{ + u32 val; + + while (i2c_dev->msg_buf_remaining) { + val = bcm2835_i2c_readl(i2c_dev, BCM2835_I2C_S); + if (!(val & BCM2835_I2C_S_RXD)) + break; + *i2c_dev->msg_buf = bcm2835_i2c_readl(i2c_dev, + BCM2835_I2C_FIFO); + i2c_dev->msg_buf++; + i2c_dev->msg_buf_remaining--; + } +} + +/* + * Repeated Start Condition (Sr) + * The BCM2835 ARM Peripherals datasheet mentions a way to trigger a Sr when it + * talks about reading from a slave with 10 bit address. This is achieved by + * issuing a write, poll the I2CS.TA flag and wait for it to be set, and then + * issue a read. + * A comment in https://github.com/raspberrypi/linux/issues/254 shows how the + * firmware actually does it using polling and says that it's a workaround for + * a problem in the state machine. + * It turns out that it is possible to use the TXW interrupt to know when the + * transfer is active, provided the FIFO has not been prefilled. + */ + +static void bcm2835_i2c_start_transfer(struct bcm2835_i2c_dev *i2c_dev) +{ + u32 c = BCM2835_I2C_C_ST | BCM2835_I2C_C_I2CEN; + struct i2c_msg *msg = i2c_dev->curr_msg; + bool last_msg = (i2c_dev->num_msgs == 1); + + if (!i2c_dev->num_msgs) + return; + + i2c_dev->num_msgs--; + i2c_dev->msg_buf = msg->buf; + i2c_dev->msg_buf_remaining = msg->len; + + if (msg->flags & I2C_M_RD) + c |= BCM2835_I2C_C_READ | BCM2835_I2C_C_INTR; + else + c |= BCM2835_I2C_C_INTT; + + if (last_msg) + c |= BCM2835_I2C_C_INTD; + + bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_A, msg->addr); + bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_DLEN, msg->len); + bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, c); +} + +static void bcm2835_i2c_finish_transfer(struct bcm2835_i2c_dev *i2c_dev) +{ + i2c_dev->curr_msg = NULL; + i2c_dev->num_msgs = 0; + + i2c_dev->msg_buf = NULL; + i2c_dev->msg_buf_remaining = 0; +} + +/* + * Note about I2C_C_CLEAR on error: + * The I2C_C_CLEAR on errors will take some time to resolve -- if you were in + * non-idle state and I2C_C_READ, it sets an abort_rx flag and runs through + * the state machine to send a NACK and a STOP. Since we're setting CLEAR + * without I2CEN, that NACK will be hanging around queued up for next time + * we start the engine. + */ + +static irqreturn_t bcm2835_i2c_isr(int this_irq, void *data) +{ + struct bcm2835_i2c_dev *i2c_dev = data; + u32 val, err; + + val = bcm2835_i2c_readl(i2c_dev, BCM2835_I2C_S); + + err = val & (BCM2835_I2C_S_CLKT | BCM2835_I2C_S_ERR); + if (err) { + i2c_dev->msg_err = err; + goto complete; + } + + if (val & BCM2835_I2C_S_DONE) { + if (!i2c_dev->curr_msg) { + dev_err(i2c_dev->dev, "Got unexpected interrupt (from firmware?)\n"); + } else if (i2c_dev->curr_msg->flags & I2C_M_RD) { + bcm2835_drain_rxfifo(i2c_dev); + val = bcm2835_i2c_readl(i2c_dev, BCM2835_I2C_S); + } + + if ((val & BCM2835_I2C_S_RXD) || i2c_dev->msg_buf_remaining) + i2c_dev->msg_err = BCM2835_I2C_S_LEN; + else + i2c_dev->msg_err = 0; + goto complete; + } + + if (val & BCM2835_I2C_S_TXW) { + if (!i2c_dev->msg_buf_remaining) { + i2c_dev->msg_err = val | BCM2835_I2C_S_LEN; + goto complete; + } + + bcm2835_fill_txfifo(i2c_dev); + + if (i2c_dev->num_msgs && !i2c_dev->msg_buf_remaining) { + i2c_dev->curr_msg++; + bcm2835_i2c_start_transfer(i2c_dev); + } + + return IRQ_HANDLED; + } + + if (val & BCM2835_I2C_S_RXR) { + if (!i2c_dev->msg_buf_remaining) { + i2c_dev->msg_err = val | BCM2835_I2C_S_LEN; + goto complete; + } + + bcm2835_drain_rxfifo(i2c_dev); + return IRQ_HANDLED; + } + + return IRQ_NONE; + +complete: + bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, BCM2835_I2C_C_CLEAR); + bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_S, BCM2835_I2C_S_CLKT | + BCM2835_I2C_S_ERR | BCM2835_I2C_S_DONE); + complete(&i2c_dev->completion); + + return IRQ_HANDLED; +} + +static int bcm2835_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], + int num) +{ + struct bcm2835_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + unsigned long time_left; + int i; + + for (i = 0; i < (num - 1); i++) + if (msgs[i].flags & I2C_M_RD) { + dev_warn_once(i2c_dev->dev, + "only one read message supported, has to be last\n"); + return -EOPNOTSUPP; + } + + i2c_dev->curr_msg = msgs; + i2c_dev->num_msgs = num; + reinit_completion(&i2c_dev->completion); + + bcm2835_i2c_start_transfer(i2c_dev); + + time_left = wait_for_completion_timeout(&i2c_dev->completion, + adap->timeout); + + bcm2835_i2c_finish_transfer(i2c_dev); + + if (!time_left) { + bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, + BCM2835_I2C_C_CLEAR); + dev_err(i2c_dev->dev, "i2c transfer timed out\n"); + return -ETIMEDOUT; + } + + if (!i2c_dev->msg_err) + return num; + + dev_dbg(i2c_dev->dev, "i2c transfer failed: %x\n", i2c_dev->msg_err); + + if (i2c_dev->msg_err & BCM2835_I2C_S_ERR) + return -EREMOTEIO; + + return -EIO; +} + +static u32 bcm2835_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm bcm2835_i2c_algo = { + .master_xfer = bcm2835_i2c_xfer, + .functionality = bcm2835_i2c_func, +}; + +/* + * The BCM2835 was reported to have problems with clock stretching: + * https://www.advamation.com/knowhow/raspberrypi/rpi-i2c-bug.html + * https://www.raspberrypi.org/forums/viewtopic.php?p=146272 + */ +static const struct i2c_adapter_quirks bcm2835_i2c_quirks = { + .flags = I2C_AQ_NO_CLK_STRETCH, +}; + +static int bcm2835_i2c_probe(struct platform_device *pdev) +{ + struct bcm2835_i2c_dev *i2c_dev; + int ret; + struct i2c_adapter *adap; + struct clk *mclk; + u32 bus_clk_rate; + + i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); + if (!i2c_dev) + return -ENOMEM; + platform_set_drvdata(pdev, i2c_dev); + i2c_dev->dev = &pdev->dev; + init_completion(&i2c_dev->completion); + + i2c_dev->regs = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(i2c_dev->regs)) + return PTR_ERR(i2c_dev->regs); + + mclk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(mclk)) + return dev_err_probe(&pdev->dev, PTR_ERR(mclk), + "Could not get clock\n"); + + i2c_dev->bus_clk = bcm2835_i2c_register_div(&pdev->dev, mclk, i2c_dev); + + if (IS_ERR(i2c_dev->bus_clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(i2c_dev->bus_clk), + "Could not register clock\n"); + + ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency", + &bus_clk_rate); + if (ret < 0) { + dev_warn(&pdev->dev, + "Could not read clock-frequency property\n"); + bus_clk_rate = I2C_MAX_STANDARD_MODE_FREQ; + } + + ret = clk_set_rate_exclusive(i2c_dev->bus_clk, bus_clk_rate); + if (ret < 0) + return dev_err_probe(&pdev->dev, ret, + "Could not set clock frequency\n"); + + ret = clk_prepare_enable(i2c_dev->bus_clk); + if (ret) { + dev_err(&pdev->dev, "Couldn't prepare clock"); + goto err_put_exclusive_rate; + } + + i2c_dev->irq = platform_get_irq(pdev, 0); + if (i2c_dev->irq < 0) { + ret = i2c_dev->irq; + goto err_disable_unprepare_clk; + } + + ret = request_irq(i2c_dev->irq, bcm2835_i2c_isr, IRQF_SHARED, + dev_name(&pdev->dev), i2c_dev); + if (ret) { + dev_err(&pdev->dev, "Could not request IRQ\n"); + goto err_disable_unprepare_clk; + } + + adap = &i2c_dev->adapter; + i2c_set_adapdata(adap, i2c_dev); + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_DEPRECATED; + snprintf(adap->name, sizeof(adap->name), "bcm2835 (%s)", + of_node_full_name(pdev->dev.of_node)); + adap->algo = &bcm2835_i2c_algo; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + adap->quirks = of_device_get_match_data(&pdev->dev); + + /* + * Disable the hardware clock stretching timeout. SMBUS + * specifies a limit for how long the device can stretch the + * clock, but core I2C doesn't. + */ + bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_CLKT, 0); + bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, 0); + + ret = i2c_add_adapter(adap); + if (ret) + goto err_free_irq; + + return 0; + +err_free_irq: + free_irq(i2c_dev->irq, i2c_dev); +err_disable_unprepare_clk: + clk_disable_unprepare(i2c_dev->bus_clk); +err_put_exclusive_rate: + clk_rate_exclusive_put(i2c_dev->bus_clk); + + return ret; +} + +static void bcm2835_i2c_remove(struct platform_device *pdev) +{ + struct bcm2835_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + + clk_rate_exclusive_put(i2c_dev->bus_clk); + clk_disable_unprepare(i2c_dev->bus_clk); + + free_irq(i2c_dev->irq, i2c_dev); + i2c_del_adapter(&i2c_dev->adapter); +} + +static const struct of_device_id bcm2835_i2c_of_match[] = { + { .compatible = "brcm,bcm2711-i2c" }, + { .compatible = "brcm,bcm2835-i2c", .data = &bcm2835_i2c_quirks }, + {}, +}; +MODULE_DEVICE_TABLE(of, bcm2835_i2c_of_match); + +static struct platform_driver bcm2835_i2c_driver = { + .probe = bcm2835_i2c_probe, + .remove_new = bcm2835_i2c_remove, + .driver = { + .name = "i2c-bcm2835", + .of_match_table = bcm2835_i2c_of_match, + }, +}; +module_platform_driver(bcm2835_i2c_driver); + +MODULE_AUTHOR("Stephen Warren <swarren@wwwdotorg.org>"); +MODULE_DESCRIPTION("BCM2835 I2C bus adapter"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:i2c-bcm2835"); diff --git a/drivers/i2c/busses/i2c-brcmstb.c b/drivers/i2c/busses/i2c-brcmstb.c new file mode 100644 index 000000000..acee76732 --- /dev/null +++ b/drivers/i2c/busses/i2c-brcmstb.c @@ -0,0 +1,735 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (C) 2014 Broadcom Corporation + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/slab.h> + +#define N_DATA_REGS 8 + +/* + * PER_I2C/BSC count register mask depends on 1 byte/4 byte data register + * size. Cable modem and DSL SoCs with Peripheral i2c cores use 1 byte per + * data register whereas STB SoCs use 4 byte per data register transfer, + * account for this difference in total count per transaction and mask to + * use. + */ +#define BSC_CNT_REG1_MASK(nb) (nb == 1 ? GENMASK(3, 0) : GENMASK(5, 0)) +#define BSC_CNT_REG1_SHIFT 0 + +/* BSC CTL register field definitions */ +#define BSC_CTL_REG_DTF_MASK 0x00000003 +#define BSC_CTL_REG_SCL_SEL_MASK 0x00000030 +#define BSC_CTL_REG_SCL_SEL_SHIFT 4 +#define BSC_CTL_REG_INT_EN_MASK 0x00000040 +#define BSC_CTL_REG_INT_EN_SHIFT 6 +#define BSC_CTL_REG_DIV_CLK_MASK 0x00000080 + +/* BSC_IIC_ENABLE r/w enable and interrupt field definitions */ +#define BSC_IIC_EN_RESTART_MASK 0x00000040 +#define BSC_IIC_EN_NOSTART_MASK 0x00000020 +#define BSC_IIC_EN_NOSTOP_MASK 0x00000010 +#define BSC_IIC_EN_NOACK_MASK 0x00000004 +#define BSC_IIC_EN_INTRP_MASK 0x00000002 +#define BSC_IIC_EN_ENABLE_MASK 0x00000001 + +/* BSC_CTLHI control register field definitions */ +#define BSC_CTLHI_REG_INPUT_SWITCHING_LEVEL_MASK 0x00000080 +#define BSC_CTLHI_REG_DATAREG_SIZE_MASK 0x00000040 +#define BSC_CTLHI_REG_IGNORE_ACK_MASK 0x00000002 +#define BSC_CTLHI_REG_WAIT_DIS_MASK 0x00000001 + +#define I2C_TIMEOUT 100 /* msecs */ + +/* Condition mask used for non combined transfer */ +#define COND_RESTART BSC_IIC_EN_RESTART_MASK +#define COND_NOSTART BSC_IIC_EN_NOSTART_MASK +#define COND_NOSTOP BSC_IIC_EN_NOSTOP_MASK +#define COND_START_STOP (COND_RESTART | COND_NOSTART | COND_NOSTOP) + +/* BSC data transfer direction */ +#define DTF_WR_MASK 0x00000000 +#define DTF_RD_MASK 0x00000001 +/* BSC data transfer direction combined format */ +#define DTF_RD_WR_MASK 0x00000002 +#define DTF_WR_RD_MASK 0x00000003 + +#define INT_ENABLE true +#define INT_DISABLE false + +/* BSC block register map structure to cache fields to be written */ +struct bsc_regs { + u32 chip_address; /* slave address */ + u32 data_in[N_DATA_REGS]; /* tx data buffer*/ + u32 cnt_reg; /* rx/tx data length */ + u32 ctl_reg; /* control register */ + u32 iic_enable; /* xfer enable and status */ + u32 data_out[N_DATA_REGS]; /* rx data buffer */ + u32 ctlhi_reg; /* more control fields */ + u32 scl_param; /* reserved */ +}; + +struct bsc_clk_param { + u32 hz; + u32 scl_mask; + u32 div_mask; +}; + +enum bsc_xfer_cmd { + CMD_WR, + CMD_RD, + CMD_WR_NOACK, + CMD_RD_NOACK, +}; + +static char const *cmd_string[] = { + [CMD_WR] = "WR", + [CMD_RD] = "RD", + [CMD_WR_NOACK] = "WR NOACK", + [CMD_RD_NOACK] = "RD NOACK", +}; + +enum bus_speeds { + SPD_375K, + SPD_390K, + SPD_187K, + SPD_200K, + SPD_93K, + SPD_97K, + SPD_46K, + SPD_50K +}; + +static const struct bsc_clk_param bsc_clk[] = { + [SPD_375K] = { + .hz = 375000, + .scl_mask = SPD_375K << BSC_CTL_REG_SCL_SEL_SHIFT, + .div_mask = 0 + }, + [SPD_390K] = { + .hz = 390000, + .scl_mask = SPD_390K << BSC_CTL_REG_SCL_SEL_SHIFT, + .div_mask = 0 + }, + [SPD_187K] = { + .hz = 187500, + .scl_mask = SPD_187K << BSC_CTL_REG_SCL_SEL_SHIFT, + .div_mask = 0 + }, + [SPD_200K] = { + .hz = 200000, + .scl_mask = SPD_200K << BSC_CTL_REG_SCL_SEL_SHIFT, + .div_mask = 0 + }, + [SPD_93K] = { + .hz = 93750, + .scl_mask = SPD_375K << BSC_CTL_REG_SCL_SEL_SHIFT, + .div_mask = BSC_CTL_REG_DIV_CLK_MASK + }, + [SPD_97K] = { + .hz = 97500, + .scl_mask = SPD_390K << BSC_CTL_REG_SCL_SEL_SHIFT, + .div_mask = BSC_CTL_REG_DIV_CLK_MASK + }, + [SPD_46K] = { + .hz = 46875, + .scl_mask = SPD_187K << BSC_CTL_REG_SCL_SEL_SHIFT, + .div_mask = BSC_CTL_REG_DIV_CLK_MASK + }, + [SPD_50K] = { + .hz = 50000, + .scl_mask = SPD_200K << BSC_CTL_REG_SCL_SEL_SHIFT, + .div_mask = BSC_CTL_REG_DIV_CLK_MASK + } +}; + +struct brcmstb_i2c_dev { + struct device *device; + void __iomem *base; + int irq; + struct bsc_regs *bsc_regmap; + struct i2c_adapter adapter; + struct completion done; + u32 clk_freq_hz; + int data_regsz; +}; + +/* register accessors for both be and le cpu arch */ +#ifdef CONFIG_CPU_BIG_ENDIAN +#define __bsc_readl(_reg) ioread32be(_reg) +#define __bsc_writel(_val, _reg) iowrite32be(_val, _reg) +#else +#define __bsc_readl(_reg) ioread32(_reg) +#define __bsc_writel(_val, _reg) iowrite32(_val, _reg) +#endif + +#define bsc_readl(_dev, _reg) \ + __bsc_readl(_dev->base + offsetof(struct bsc_regs, _reg)) + +#define bsc_writel(_dev, _val, _reg) \ + __bsc_writel(_val, _dev->base + offsetof(struct bsc_regs, _reg)) + +static inline int brcmstb_i2c_get_xfersz(struct brcmstb_i2c_dev *dev) +{ + return (N_DATA_REGS * dev->data_regsz); +} + +static inline int brcmstb_i2c_get_data_regsz(struct brcmstb_i2c_dev *dev) +{ + return dev->data_regsz; +} + +static void brcmstb_i2c_enable_disable_irq(struct brcmstb_i2c_dev *dev, + bool int_en) +{ + + if (int_en) + /* Enable BSC CTL interrupt line */ + dev->bsc_regmap->ctl_reg |= BSC_CTL_REG_INT_EN_MASK; + else + /* Disable BSC CTL interrupt line */ + dev->bsc_regmap->ctl_reg &= ~BSC_CTL_REG_INT_EN_MASK; + + barrier(); + bsc_writel(dev, dev->bsc_regmap->ctl_reg, ctl_reg); +} + +static irqreturn_t brcmstb_i2c_isr(int irq, void *devid) +{ + struct brcmstb_i2c_dev *dev = devid; + u32 status_bsc_ctl = bsc_readl(dev, ctl_reg); + u32 status_iic_intrp = bsc_readl(dev, iic_enable); + + dev_dbg(dev->device, "isr CTL_REG %x IIC_EN %x\n", + status_bsc_ctl, status_iic_intrp); + + if (!(status_bsc_ctl & BSC_CTL_REG_INT_EN_MASK)) + return IRQ_NONE; + + brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE); + complete(&dev->done); + + dev_dbg(dev->device, "isr handled"); + return IRQ_HANDLED; +} + +/* Wait for device to be ready */ +static int brcmstb_i2c_wait_if_busy(struct brcmstb_i2c_dev *dev) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(I2C_TIMEOUT); + + while ((bsc_readl(dev, iic_enable) & BSC_IIC_EN_INTRP_MASK)) { + if (time_after(jiffies, timeout)) + return -ETIMEDOUT; + cpu_relax(); + } + return 0; +} + +/* i2c xfer completion function, handles both irq and polling mode */ +static int brcmstb_i2c_wait_for_completion(struct brcmstb_i2c_dev *dev) +{ + int ret = 0; + unsigned long timeout = msecs_to_jiffies(I2C_TIMEOUT); + + if (dev->irq >= 0) { + if (!wait_for_completion_timeout(&dev->done, timeout)) + ret = -ETIMEDOUT; + } else { + /* we are in polling mode */ + u32 bsc_intrp; + unsigned long time_left = jiffies + timeout; + + do { + bsc_intrp = bsc_readl(dev, iic_enable) & + BSC_IIC_EN_INTRP_MASK; + if (time_after(jiffies, time_left)) { + ret = -ETIMEDOUT; + break; + } + cpu_relax(); + } while (!bsc_intrp); + } + + if (dev->irq < 0 || ret == -ETIMEDOUT) + brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE); + + return ret; +} + +/* Set xfer START/STOP conditions for subsequent transfer */ +static void brcmstb_set_i2c_start_stop(struct brcmstb_i2c_dev *dev, + u32 cond_flag) +{ + u32 regval = dev->bsc_regmap->iic_enable; + + dev->bsc_regmap->iic_enable = (regval & ~COND_START_STOP) | cond_flag; +} + +/* Send I2C request check completion */ +static int brcmstb_send_i2c_cmd(struct brcmstb_i2c_dev *dev, + enum bsc_xfer_cmd cmd) +{ + int rc = 0; + struct bsc_regs *pi2creg = dev->bsc_regmap; + + /* Make sure the hardware is ready */ + rc = brcmstb_i2c_wait_if_busy(dev); + if (rc < 0) + return rc; + + /* only if we are in interrupt mode */ + if (dev->irq >= 0) + reinit_completion(&dev->done); + + /* enable BSC CTL interrupt line */ + brcmstb_i2c_enable_disable_irq(dev, INT_ENABLE); + + /* initiate transfer by setting iic_enable */ + pi2creg->iic_enable |= BSC_IIC_EN_ENABLE_MASK; + bsc_writel(dev, pi2creg->iic_enable, iic_enable); + + /* Wait for transaction to finish or timeout */ + rc = brcmstb_i2c_wait_for_completion(dev); + if (rc) { + dev_dbg(dev->device, "intr timeout for cmd %s\n", + cmd_string[cmd]); + goto cmd_out; + } + + if ((cmd == CMD_RD || cmd == CMD_WR) && + bsc_readl(dev, iic_enable) & BSC_IIC_EN_NOACK_MASK) { + rc = -EREMOTEIO; + dev_dbg(dev->device, "controller received NOACK intr for %s\n", + cmd_string[cmd]); + } + +cmd_out: + bsc_writel(dev, 0, cnt_reg); + bsc_writel(dev, 0, iic_enable); + + return rc; +} + +/* Actual data transfer through the BSC master */ +static int brcmstb_i2c_xfer_bsc_data(struct brcmstb_i2c_dev *dev, + u8 *buf, unsigned int len, + struct i2c_msg *pmsg) +{ + int cnt, byte, i, rc; + enum bsc_xfer_cmd cmd; + u32 ctl_reg; + struct bsc_regs *pi2creg = dev->bsc_regmap; + int no_ack = pmsg->flags & I2C_M_IGNORE_NAK; + int data_regsz = brcmstb_i2c_get_data_regsz(dev); + + /* see if the transaction needs to check NACK conditions */ + if (no_ack) { + cmd = (pmsg->flags & I2C_M_RD) ? CMD_RD_NOACK + : CMD_WR_NOACK; + pi2creg->ctlhi_reg |= BSC_CTLHI_REG_IGNORE_ACK_MASK; + } else { + cmd = (pmsg->flags & I2C_M_RD) ? CMD_RD : CMD_WR; + pi2creg->ctlhi_reg &= ~BSC_CTLHI_REG_IGNORE_ACK_MASK; + } + bsc_writel(dev, pi2creg->ctlhi_reg, ctlhi_reg); + + /* set data transfer direction */ + ctl_reg = pi2creg->ctl_reg & ~BSC_CTL_REG_DTF_MASK; + if (cmd == CMD_WR || cmd == CMD_WR_NOACK) + pi2creg->ctl_reg = ctl_reg | DTF_WR_MASK; + else + pi2creg->ctl_reg = ctl_reg | DTF_RD_MASK; + + /* set the read/write length */ + bsc_writel(dev, BSC_CNT_REG1_MASK(data_regsz) & + (len << BSC_CNT_REG1_SHIFT), cnt_reg); + + /* Write data into data_in register */ + + if (cmd == CMD_WR || cmd == CMD_WR_NOACK) { + for (cnt = 0, i = 0; cnt < len; cnt += data_regsz, i++) { + u32 word = 0; + + for (byte = 0; byte < data_regsz; byte++) { + word >>= BITS_PER_BYTE; + if ((cnt + byte) < len) + word |= buf[cnt + byte] << + (BITS_PER_BYTE * (data_regsz - 1)); + } + bsc_writel(dev, word, data_in[i]); + } + } + + /* Initiate xfer, the function will return on completion */ + rc = brcmstb_send_i2c_cmd(dev, cmd); + + if (rc != 0) { + dev_dbg(dev->device, "%s failure", cmd_string[cmd]); + return rc; + } + + /* Read data from data_out register */ + if (cmd == CMD_RD || cmd == CMD_RD_NOACK) { + for (cnt = 0, i = 0; cnt < len; cnt += data_regsz, i++) { + u32 data = bsc_readl(dev, data_out[i]); + + for (byte = 0; byte < data_regsz && + (byte + cnt) < len; byte++) { + buf[cnt + byte] = data & 0xff; + data >>= BITS_PER_BYTE; + } + } + } + + return 0; +} + +/* Write a single byte of data to the i2c bus */ +static int brcmstb_i2c_write_data_byte(struct brcmstb_i2c_dev *dev, + u8 *buf, unsigned int nak_expected) +{ + enum bsc_xfer_cmd cmd = nak_expected ? CMD_WR : CMD_WR_NOACK; + + bsc_writel(dev, 1, cnt_reg); + bsc_writel(dev, *buf, data_in); + + return brcmstb_send_i2c_cmd(dev, cmd); +} + +/* Send i2c address */ +static int brcmstb_i2c_do_addr(struct brcmstb_i2c_dev *dev, + struct i2c_msg *msg) +{ + unsigned char addr; + + if (msg->flags & I2C_M_TEN) { + /* First byte is 11110XX0 where XX is upper 2 bits */ + addr = 0xF0 | ((msg->addr & 0x300) >> 7); + bsc_writel(dev, addr, chip_address); + + /* Second byte is the remaining 8 bits */ + addr = msg->addr & 0xFF; + if (brcmstb_i2c_write_data_byte(dev, &addr, 0) < 0) + return -EREMOTEIO; + + if (msg->flags & I2C_M_RD) { + /* For read, send restart without stop condition */ + brcmstb_set_i2c_start_stop(dev, COND_RESTART + | COND_NOSTOP); + /* Then re-send the first byte with the read bit set */ + addr = 0xF0 | ((msg->addr & 0x300) >> 7) | 0x01; + if (brcmstb_i2c_write_data_byte(dev, &addr, 0) < 0) + return -EREMOTEIO; + + } + } else { + addr = i2c_8bit_addr_from_msg(msg); + + bsc_writel(dev, addr, chip_address); + } + + return 0; +} + +/* Master transfer function */ +static int brcmstb_i2c_xfer(struct i2c_adapter *adapter, + struct i2c_msg msgs[], int num) +{ + struct brcmstb_i2c_dev *dev = i2c_get_adapdata(adapter); + struct i2c_msg *pmsg; + int rc = 0; + int i; + int bytes_to_xfer; + u8 *tmp_buf; + int len = 0; + int xfersz = brcmstb_i2c_get_xfersz(dev); + u32 cond, cond_per_msg; + + /* Loop through all messages */ + for (i = 0; i < num; i++) { + pmsg = &msgs[i]; + len = pmsg->len; + tmp_buf = pmsg->buf; + + dev_dbg(dev->device, + "msg# %d/%d flg %x buf %x len %d\n", i, + num - 1, pmsg->flags, + pmsg->buf ? pmsg->buf[0] : '0', pmsg->len); + + if (i < (num - 1) && (msgs[i + 1].flags & I2C_M_NOSTART)) + cond = ~COND_START_STOP; + else + cond = COND_RESTART | COND_NOSTOP; + + brcmstb_set_i2c_start_stop(dev, cond); + + /* Send slave address */ + if (!(pmsg->flags & I2C_M_NOSTART)) { + rc = brcmstb_i2c_do_addr(dev, pmsg); + if (rc < 0) { + dev_dbg(dev->device, + "NACK for addr %2.2x msg#%d rc = %d\n", + pmsg->addr, i, rc); + goto out; + } + } + + cond_per_msg = cond; + + /* Perform data transfer */ + while (len) { + bytes_to_xfer = min(len, xfersz); + + if (len <= xfersz) { + if (i == (num - 1)) + cond_per_msg = cond_per_msg & + ~(COND_RESTART | COND_NOSTOP); + else + cond_per_msg = cond; + } else { + cond_per_msg = (cond_per_msg & ~COND_RESTART) | + COND_NOSTOP; + } + + brcmstb_set_i2c_start_stop(dev, cond_per_msg); + + rc = brcmstb_i2c_xfer_bsc_data(dev, tmp_buf, + bytes_to_xfer, pmsg); + if (rc < 0) + goto out; + + len -= bytes_to_xfer; + tmp_buf += bytes_to_xfer; + + cond_per_msg = COND_NOSTART | COND_NOSTOP; + } + } + + rc = num; +out: + return rc; + +} + +static u32 brcmstb_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR + | I2C_FUNC_NOSTART | I2C_FUNC_PROTOCOL_MANGLING; +} + +static const struct i2c_algorithm brcmstb_i2c_algo = { + .master_xfer = brcmstb_i2c_xfer, + .functionality = brcmstb_i2c_functionality, +}; + +static void brcmstb_i2c_set_bus_speed(struct brcmstb_i2c_dev *dev) +{ + int i = 0, num_speeds = ARRAY_SIZE(bsc_clk); + u32 clk_freq_hz = dev->clk_freq_hz; + + for (i = 0; i < num_speeds; i++) { + if (bsc_clk[i].hz == clk_freq_hz) { + dev->bsc_regmap->ctl_reg &= ~(BSC_CTL_REG_SCL_SEL_MASK + | BSC_CTL_REG_DIV_CLK_MASK); + dev->bsc_regmap->ctl_reg |= (bsc_clk[i].scl_mask | + bsc_clk[i].div_mask); + bsc_writel(dev, dev->bsc_regmap->ctl_reg, ctl_reg); + break; + } + } + + /* in case we did not get find a valid speed */ + if (i == num_speeds) { + i = (bsc_readl(dev, ctl_reg) & BSC_CTL_REG_SCL_SEL_MASK) >> + BSC_CTL_REG_SCL_SEL_SHIFT; + dev_warn(dev->device, "leaving current clock-frequency @ %dHz\n", + bsc_clk[i].hz); + } +} + +static void brcmstb_i2c_set_bsc_reg_defaults(struct brcmstb_i2c_dev *dev) +{ + if (brcmstb_i2c_get_data_regsz(dev) == sizeof(u32)) + /* set 4 byte data in/out xfers */ + dev->bsc_regmap->ctlhi_reg = BSC_CTLHI_REG_DATAREG_SIZE_MASK; + else + dev->bsc_regmap->ctlhi_reg &= ~BSC_CTLHI_REG_DATAREG_SIZE_MASK; + + bsc_writel(dev, dev->bsc_regmap->ctlhi_reg, ctlhi_reg); + /* set bus speed */ + brcmstb_i2c_set_bus_speed(dev); +} + +#define AUTOI2C_CTRL0 0x26c +#define AUTOI2C_CTRL0_RELEASE_BSC BIT(1) + +static int bcm2711_release_bsc(struct brcmstb_i2c_dev *dev) +{ + struct platform_device *pdev = to_platform_device(dev->device); + void __iomem *autoi2c; + + /* Map hardware registers */ + autoi2c = devm_platform_ioremap_resource_byname(pdev, "auto-i2c"); + if (IS_ERR(autoi2c)) + return PTR_ERR(autoi2c); + + writel(AUTOI2C_CTRL0_RELEASE_BSC, autoi2c + AUTOI2C_CTRL0); + devm_iounmap(&pdev->dev, autoi2c); + + /* We need to reset the controller after the release */ + dev->bsc_regmap->iic_enable = 0; + bsc_writel(dev, dev->bsc_regmap->iic_enable, iic_enable); + + return 0; +} + +static int brcmstb_i2c_probe(struct platform_device *pdev) +{ + struct brcmstb_i2c_dev *dev; + struct i2c_adapter *adap; + const char *int_name; + int rc; + + /* Allocate memory for private data structure */ + dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + + dev->bsc_regmap = devm_kzalloc(&pdev->dev, sizeof(*dev->bsc_regmap), GFP_KERNEL); + if (!dev->bsc_regmap) + return -ENOMEM; + + platform_set_drvdata(pdev, dev); + dev->device = &pdev->dev; + init_completion(&dev->done); + + /* Map hardware registers */ + dev->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(dev->base)) + return PTR_ERR(dev->base); + + if (of_device_is_compatible(dev->device->of_node, + "brcm,bcm2711-hdmi-i2c")) { + rc = bcm2711_release_bsc(dev); + if (rc) + return rc; + } + + rc = of_property_read_string(dev->device->of_node, "interrupt-names", + &int_name); + if (rc < 0) + int_name = NULL; + + /* Get the interrupt number */ + dev->irq = platform_get_irq_optional(pdev, 0); + + /* disable the bsc interrupt line */ + brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE); + + /* register the ISR handler */ + if (dev->irq >= 0) { + rc = devm_request_irq(&pdev->dev, dev->irq, brcmstb_i2c_isr, + IRQF_SHARED, + int_name ? int_name : pdev->name, + dev); + + if (rc) { + dev_dbg(dev->device, "falling back to polling mode"); + dev->irq = -1; + } + } + + if (of_property_read_u32(dev->device->of_node, + "clock-frequency", &dev->clk_freq_hz)) { + dev_warn(dev->device, "setting clock-frequency@%dHz\n", + bsc_clk[0].hz); + dev->clk_freq_hz = bsc_clk[0].hz; + } + + /* set the data in/out register size for compatible SoCs */ + if (of_device_is_compatible(dev->device->of_node, + "brcm,brcmper-i2c")) + dev->data_regsz = sizeof(u8); + else + dev->data_regsz = sizeof(u32); + + brcmstb_i2c_set_bsc_reg_defaults(dev); + + /* Add the i2c adapter */ + adap = &dev->adapter; + i2c_set_adapdata(adap, dev); + adap->owner = THIS_MODULE; + strscpy(adap->name, dev_name(&pdev->dev), sizeof(adap->name)); + adap->algo = &brcmstb_i2c_algo; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + rc = i2c_add_adapter(adap); + if (rc) + return rc; + + dev_info(dev->device, "%s@%dhz registered in %s mode\n", + int_name ? int_name : " ", dev->clk_freq_hz, + (dev->irq >= 0) ? "interrupt" : "polling"); + + return 0; +} + +static void brcmstb_i2c_remove(struct platform_device *pdev) +{ + struct brcmstb_i2c_dev *dev = platform_get_drvdata(pdev); + + i2c_del_adapter(&dev->adapter); +} + +static int brcmstb_i2c_suspend(struct device *dev) +{ + struct brcmstb_i2c_dev *i2c_dev = dev_get_drvdata(dev); + + i2c_mark_adapter_suspended(&i2c_dev->adapter); + return 0; +} + +static int brcmstb_i2c_resume(struct device *dev) +{ + struct brcmstb_i2c_dev *i2c_dev = dev_get_drvdata(dev); + + brcmstb_i2c_set_bsc_reg_defaults(i2c_dev); + i2c_mark_adapter_resumed(&i2c_dev->adapter); + + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(brcmstb_i2c_pm, brcmstb_i2c_suspend, + brcmstb_i2c_resume); + +static const struct of_device_id brcmstb_i2c_of_match[] = { + {.compatible = "brcm,brcmstb-i2c"}, + {.compatible = "brcm,brcmper-i2c"}, + {.compatible = "brcm,bcm2711-hdmi-i2c"}, + {}, +}; +MODULE_DEVICE_TABLE(of, brcmstb_i2c_of_match); + +static struct platform_driver brcmstb_i2c_driver = { + .driver = { + .name = "brcmstb-i2c", + .of_match_table = brcmstb_i2c_of_match, + .pm = pm_sleep_ptr(&brcmstb_i2c_pm), + }, + .probe = brcmstb_i2c_probe, + .remove_new = brcmstb_i2c_remove, +}; +module_platform_driver(brcmstb_i2c_driver); + +MODULE_AUTHOR("Kamal Dasu <kdasu@broadcom.com>"); +MODULE_DESCRIPTION("Broadcom Settop I2C Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-cadence.c b/drivers/i2c/busses/i2c-cadence.c new file mode 100644 index 000000000..de3f58b60 --- /dev/null +++ b/drivers/i2c/busses/i2c-cadence.c @@ -0,0 +1,1447 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * I2C bus driver for the Cadence I2C controller. + * + * Copyright (C) 2009 - 2014 Xilinx, Inc. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/of.h> +#include <linux/pm_runtime.h> +#include <linux/pinctrl/consumer.h> +#include <linux/reset.h> + +/* Register offsets for the I2C device. */ +#define CDNS_I2C_CR_OFFSET 0x00 /* Control Register, RW */ +#define CDNS_I2C_SR_OFFSET 0x04 /* Status Register, RO */ +#define CDNS_I2C_ADDR_OFFSET 0x08 /* I2C Address Register, RW */ +#define CDNS_I2C_DATA_OFFSET 0x0C /* I2C Data Register, RW */ +#define CDNS_I2C_ISR_OFFSET 0x10 /* IRQ Status Register, RW */ +#define CDNS_I2C_XFER_SIZE_OFFSET 0x14 /* Transfer Size Register, RW */ +#define CDNS_I2C_TIME_OUT_OFFSET 0x1C /* Time Out Register, RW */ +#define CDNS_I2C_IMR_OFFSET 0x20 /* IRQ Mask Register, RO */ +#define CDNS_I2C_IER_OFFSET 0x24 /* IRQ Enable Register, WO */ +#define CDNS_I2C_IDR_OFFSET 0x28 /* IRQ Disable Register, WO */ + +/* Control Register Bit mask definitions */ +#define CDNS_I2C_CR_HOLD BIT(4) /* Hold Bus bit */ +#define CDNS_I2C_CR_ACK_EN BIT(3) +#define CDNS_I2C_CR_NEA BIT(2) +#define CDNS_I2C_CR_MS BIT(1) +/* Read or Write Master transfer 0 = Transmitter, 1 = Receiver */ +#define CDNS_I2C_CR_RW BIT(0) +/* 1 = Auto init FIFO to zeroes */ +#define CDNS_I2C_CR_CLR_FIFO BIT(6) +#define CDNS_I2C_CR_DIVA_SHIFT 14 +#define CDNS_I2C_CR_DIVA_MASK (3 << CDNS_I2C_CR_DIVA_SHIFT) +#define CDNS_I2C_CR_DIVB_SHIFT 8 +#define CDNS_I2C_CR_DIVB_MASK (0x3f << CDNS_I2C_CR_DIVB_SHIFT) + +#define CDNS_I2C_CR_MASTER_EN_MASK (CDNS_I2C_CR_NEA | \ + CDNS_I2C_CR_ACK_EN | \ + CDNS_I2C_CR_MS) + +#define CDNS_I2C_CR_SLAVE_EN_MASK ~CDNS_I2C_CR_MASTER_EN_MASK + +/* Status Register Bit mask definitions */ +#define CDNS_I2C_SR_BA BIT(8) +#define CDNS_I2C_SR_TXDV BIT(6) +#define CDNS_I2C_SR_RXDV BIT(5) +#define CDNS_I2C_SR_RXRW BIT(3) + +/* + * I2C Address Register Bit mask definitions + * Normal addressing mode uses [6:0] bits. Extended addressing mode uses [9:0] + * bits. A write access to this register always initiates a transfer if the I2C + * is in master mode. + */ +#define CDNS_I2C_ADDR_MASK 0x000003FF /* I2C Address Mask */ + +/* + * I2C Interrupt Registers Bit mask definitions + * All the four interrupt registers (Status/Mask/Enable/Disable) have the same + * bit definitions. + */ +#define CDNS_I2C_IXR_ARB_LOST BIT(9) +#define CDNS_I2C_IXR_RX_UNF BIT(7) +#define CDNS_I2C_IXR_TX_OVF BIT(6) +#define CDNS_I2C_IXR_RX_OVF BIT(5) +#define CDNS_I2C_IXR_SLV_RDY BIT(4) +#define CDNS_I2C_IXR_TO BIT(3) +#define CDNS_I2C_IXR_NACK BIT(2) +#define CDNS_I2C_IXR_DATA BIT(1) +#define CDNS_I2C_IXR_COMP BIT(0) + +#define CDNS_I2C_IXR_ALL_INTR_MASK (CDNS_I2C_IXR_ARB_LOST | \ + CDNS_I2C_IXR_RX_UNF | \ + CDNS_I2C_IXR_TX_OVF | \ + CDNS_I2C_IXR_RX_OVF | \ + CDNS_I2C_IXR_SLV_RDY | \ + CDNS_I2C_IXR_TO | \ + CDNS_I2C_IXR_NACK | \ + CDNS_I2C_IXR_DATA | \ + CDNS_I2C_IXR_COMP) + +#define CDNS_I2C_IXR_ERR_INTR_MASK (CDNS_I2C_IXR_ARB_LOST | \ + CDNS_I2C_IXR_RX_UNF | \ + CDNS_I2C_IXR_TX_OVF | \ + CDNS_I2C_IXR_RX_OVF | \ + CDNS_I2C_IXR_NACK) + +#define CDNS_I2C_ENABLED_INTR_MASK (CDNS_I2C_IXR_ARB_LOST | \ + CDNS_I2C_IXR_RX_UNF | \ + CDNS_I2C_IXR_TX_OVF | \ + CDNS_I2C_IXR_RX_OVF | \ + CDNS_I2C_IXR_NACK | \ + CDNS_I2C_IXR_DATA | \ + CDNS_I2C_IXR_COMP) + +#define CDNS_I2C_IXR_SLAVE_INTR_MASK (CDNS_I2C_IXR_RX_UNF | \ + CDNS_I2C_IXR_TX_OVF | \ + CDNS_I2C_IXR_RX_OVF | \ + CDNS_I2C_IXR_TO | \ + CDNS_I2C_IXR_NACK | \ + CDNS_I2C_IXR_DATA | \ + CDNS_I2C_IXR_COMP) + +#define CDNS_I2C_TIMEOUT msecs_to_jiffies(1000) +/* timeout for pm runtime autosuspend */ +#define CNDS_I2C_PM_TIMEOUT 1000 /* ms */ + +#define CDNS_I2C_FIFO_DEPTH_DEFAULT 16 +#define CDNS_I2C_MAX_TRANSFER_SIZE 255 +/* Transfer size in multiples of data interrupt depth */ +#define CDNS_I2C_TRANSFER_SIZE(max) ((max) - 3) + +#define DRIVER_NAME "cdns-i2c" + +#define CDNS_I2C_DIVA_MAX 4 +#define CDNS_I2C_DIVB_MAX 64 + +#define CDNS_I2C_TIMEOUT_MAX 0xFF + +#define CDNS_I2C_BROKEN_HOLD_BIT BIT(0) +#define CDNS_I2C_POLL_US 100000 +#define CDNS_I2C_TIMEOUT_US 500000 + +#define cdns_i2c_readreg(offset) readl_relaxed(id->membase + offset) +#define cdns_i2c_writereg(val, offset) writel_relaxed(val, id->membase + offset) + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +/** + * enum cdns_i2c_mode - I2C Controller current operating mode + * + * @CDNS_I2C_MODE_SLAVE: I2C controller operating in slave mode + * @CDNS_I2C_MODE_MASTER: I2C Controller operating in master mode + */ +enum cdns_i2c_mode { + CDNS_I2C_MODE_SLAVE, + CDNS_I2C_MODE_MASTER, +}; + +/** + * enum cdns_i2c_slave_state - Slave state when I2C is operating in slave mode + * + * @CDNS_I2C_SLAVE_STATE_IDLE: I2C slave idle + * @CDNS_I2C_SLAVE_STATE_SEND: I2C slave sending data to master + * @CDNS_I2C_SLAVE_STATE_RECV: I2C slave receiving data from master + */ +enum cdns_i2c_slave_state { + CDNS_I2C_SLAVE_STATE_IDLE, + CDNS_I2C_SLAVE_STATE_SEND, + CDNS_I2C_SLAVE_STATE_RECV, +}; +#endif + +/** + * struct cdns_i2c - I2C device private data structure + * + * @dev: Pointer to device structure + * @membase: Base address of the I2C device + * @adap: I2C adapter instance + * @p_msg: Message pointer + * @err_status: Error status in Interrupt Status Register + * @xfer_done: Transfer complete status + * @p_send_buf: Pointer to transmit buffer + * @p_recv_buf: Pointer to receive buffer + * @send_count: Number of bytes still expected to send + * @recv_count: Number of bytes still expected to receive + * @curr_recv_count: Number of bytes to be received in current transfer + * @input_clk: Input clock to I2C controller + * @i2c_clk: Maximum I2C clock speed + * @bus_hold_flag: Flag used in repeated start for clearing HOLD bit + * @clk: Pointer to struct clk + * @clk_rate_change_nb: Notifier block for clock rate changes + * @reset: Reset control for the device + * @quirks: flag for broken hold bit usage in r1p10 + * @ctrl_reg: Cached value of the control register. + * @rinfo: I2C GPIO recovery information + * @ctrl_reg_diva_divb: value of fields DIV_A and DIV_B from CR register + * @slave: Registered slave instance. + * @dev_mode: I2C operating role(master/slave). + * @slave_state: I2C Slave state(idle/read/write). + * @fifo_depth: The depth of the transfer FIFO + * @transfer_size: The maximum number of bytes in one transfer + */ +struct cdns_i2c { + struct device *dev; + void __iomem *membase; + struct i2c_adapter adap; + struct i2c_msg *p_msg; + int err_status; + struct completion xfer_done; + unsigned char *p_send_buf; + unsigned char *p_recv_buf; + unsigned int send_count; + unsigned int recv_count; + unsigned int curr_recv_count; + unsigned long input_clk; + unsigned int i2c_clk; + unsigned int bus_hold_flag; + struct clk *clk; + struct notifier_block clk_rate_change_nb; + struct reset_control *reset; + u32 quirks; + u32 ctrl_reg; + struct i2c_bus_recovery_info rinfo; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + u16 ctrl_reg_diva_divb; + struct i2c_client *slave; + enum cdns_i2c_mode dev_mode; + enum cdns_i2c_slave_state slave_state; +#endif + u32 fifo_depth; + unsigned int transfer_size; +}; + +struct cdns_platform_data { + u32 quirks; +}; + +#define to_cdns_i2c(_nb) container_of(_nb, struct cdns_i2c, \ + clk_rate_change_nb) + +/** + * cdns_i2c_clear_bus_hold - Clear bus hold bit + * @id: Pointer to driver data struct + * + * Helper to clear the controller's bus hold bit. + */ +static void cdns_i2c_clear_bus_hold(struct cdns_i2c *id) +{ + u32 reg = cdns_i2c_readreg(CDNS_I2C_CR_OFFSET); + if (reg & CDNS_I2C_CR_HOLD) + cdns_i2c_writereg(reg & ~CDNS_I2C_CR_HOLD, CDNS_I2C_CR_OFFSET); +} + +static inline bool cdns_is_holdquirk(struct cdns_i2c *id, bool hold_wrkaround) +{ + return (hold_wrkaround && + (id->curr_recv_count == id->fifo_depth + 1)); +} + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +static void cdns_i2c_set_mode(enum cdns_i2c_mode mode, struct cdns_i2c *id) +{ + /* Disable all interrupts */ + cdns_i2c_writereg(CDNS_I2C_IXR_ALL_INTR_MASK, CDNS_I2C_IDR_OFFSET); + + /* Clear FIFO and transfer size */ + cdns_i2c_writereg(CDNS_I2C_CR_CLR_FIFO, CDNS_I2C_CR_OFFSET); + + /* Update device mode and state */ + id->dev_mode = mode; + id->slave_state = CDNS_I2C_SLAVE_STATE_IDLE; + + switch (mode) { + case CDNS_I2C_MODE_MASTER: + /* Enable i2c master */ + cdns_i2c_writereg(id->ctrl_reg_diva_divb | + CDNS_I2C_CR_MASTER_EN_MASK, + CDNS_I2C_CR_OFFSET); + /* + * This delay is needed to give the IP some time to switch to + * the master mode. With lower values(like 110 us) i2cdetect + * will not detect any slave and without this delay, the IP will + * trigger a timeout interrupt. + */ + usleep_range(115, 125); + break; + case CDNS_I2C_MODE_SLAVE: + /* Enable i2c slave */ + cdns_i2c_writereg(id->ctrl_reg_diva_divb & + CDNS_I2C_CR_SLAVE_EN_MASK, + CDNS_I2C_CR_OFFSET); + + /* Setting slave address */ + cdns_i2c_writereg(id->slave->addr & CDNS_I2C_ADDR_MASK, + CDNS_I2C_ADDR_OFFSET); + + /* Enable slave send/receive interrupts */ + cdns_i2c_writereg(CDNS_I2C_IXR_SLAVE_INTR_MASK, + CDNS_I2C_IER_OFFSET); + break; + } +} + +static void cdns_i2c_slave_rcv_data(struct cdns_i2c *id) +{ + u8 bytes; + unsigned char data; + + /* Prepare backend for data reception */ + if (id->slave_state == CDNS_I2C_SLAVE_STATE_IDLE) { + id->slave_state = CDNS_I2C_SLAVE_STATE_RECV; + i2c_slave_event(id->slave, I2C_SLAVE_WRITE_REQUESTED, NULL); + } + + /* Fetch number of bytes to receive */ + bytes = cdns_i2c_readreg(CDNS_I2C_XFER_SIZE_OFFSET); + + /* Read data and send to backend */ + while (bytes--) { + data = cdns_i2c_readreg(CDNS_I2C_DATA_OFFSET); + i2c_slave_event(id->slave, I2C_SLAVE_WRITE_RECEIVED, &data); + } +} + +static void cdns_i2c_slave_send_data(struct cdns_i2c *id) +{ + u8 data; + + /* Prepare backend for data transmission */ + if (id->slave_state == CDNS_I2C_SLAVE_STATE_IDLE) { + id->slave_state = CDNS_I2C_SLAVE_STATE_SEND; + i2c_slave_event(id->slave, I2C_SLAVE_READ_REQUESTED, &data); + } else { + i2c_slave_event(id->slave, I2C_SLAVE_READ_PROCESSED, &data); + } + + /* Send data over bus */ + cdns_i2c_writereg(data, CDNS_I2C_DATA_OFFSET); +} + +/** + * cdns_i2c_slave_isr - Interrupt handler for the I2C device in slave role + * @ptr: Pointer to I2C device private data + * + * This function handles the data interrupt and transfer complete interrupt of + * the I2C device in slave role. + * + * Return: IRQ_HANDLED always + */ +static irqreturn_t cdns_i2c_slave_isr(void *ptr) +{ + struct cdns_i2c *id = ptr; + unsigned int isr_status, i2c_status; + + /* Fetch the interrupt status */ + isr_status = cdns_i2c_readreg(CDNS_I2C_ISR_OFFSET); + cdns_i2c_writereg(isr_status, CDNS_I2C_ISR_OFFSET); + + /* Ignore masked interrupts */ + isr_status &= ~cdns_i2c_readreg(CDNS_I2C_IMR_OFFSET); + + /* Fetch transfer mode (send/receive) */ + i2c_status = cdns_i2c_readreg(CDNS_I2C_SR_OFFSET); + + /* Handle data send/receive */ + if (i2c_status & CDNS_I2C_SR_RXRW) { + /* Send data to master */ + if (isr_status & CDNS_I2C_IXR_DATA) + cdns_i2c_slave_send_data(id); + + if (isr_status & CDNS_I2C_IXR_COMP) { + id->slave_state = CDNS_I2C_SLAVE_STATE_IDLE; + i2c_slave_event(id->slave, I2C_SLAVE_STOP, NULL); + } + } else { + /* Receive data from master */ + if (isr_status & CDNS_I2C_IXR_DATA) + cdns_i2c_slave_rcv_data(id); + + if (isr_status & CDNS_I2C_IXR_COMP) { + cdns_i2c_slave_rcv_data(id); + id->slave_state = CDNS_I2C_SLAVE_STATE_IDLE; + i2c_slave_event(id->slave, I2C_SLAVE_STOP, NULL); + } + } + + /* Master indicated xfer stop or fifo underflow/overflow */ + if (isr_status & (CDNS_I2C_IXR_NACK | CDNS_I2C_IXR_RX_OVF | + CDNS_I2C_IXR_RX_UNF | CDNS_I2C_IXR_TX_OVF)) { + id->slave_state = CDNS_I2C_SLAVE_STATE_IDLE; + i2c_slave_event(id->slave, I2C_SLAVE_STOP, NULL); + cdns_i2c_writereg(CDNS_I2C_CR_CLR_FIFO, CDNS_I2C_CR_OFFSET); + } + + return IRQ_HANDLED; +} +#endif + +/** + * cdns_i2c_master_isr - Interrupt handler for the I2C device in master role + * @ptr: Pointer to I2C device private data + * + * This function handles the data interrupt, transfer complete interrupt and + * the error interrupts of the I2C device in master role. + * + * Return: IRQ_HANDLED always + */ +static irqreturn_t cdns_i2c_master_isr(void *ptr) +{ + unsigned int isr_status, avail_bytes; + unsigned int bytes_to_send; + bool updatetx; + struct cdns_i2c *id = ptr; + /* Signal completion only after everything is updated */ + int done_flag = 0; + irqreturn_t status = IRQ_NONE; + + isr_status = cdns_i2c_readreg(CDNS_I2C_ISR_OFFSET); + cdns_i2c_writereg(isr_status, CDNS_I2C_ISR_OFFSET); + id->err_status = 0; + + /* Handling nack and arbitration lost interrupt */ + if (isr_status & (CDNS_I2C_IXR_NACK | CDNS_I2C_IXR_ARB_LOST)) { + done_flag = 1; + status = IRQ_HANDLED; + } + + /* + * Check if transfer size register needs to be updated again for a + * large data receive operation. + */ + updatetx = id->recv_count > id->curr_recv_count; + + /* When receiving, handle data interrupt and completion interrupt */ + if (id->p_recv_buf && + ((isr_status & CDNS_I2C_IXR_COMP) || + (isr_status & CDNS_I2C_IXR_DATA))) { + /* Read data if receive data valid is set */ + while (cdns_i2c_readreg(CDNS_I2C_SR_OFFSET) & + CDNS_I2C_SR_RXDV) { + if (id->recv_count > 0) { + *(id->p_recv_buf)++ = + cdns_i2c_readreg(CDNS_I2C_DATA_OFFSET); + id->recv_count--; + id->curr_recv_count--; + + /* + * Clear hold bit that was set for FIFO control + * if RX data left is less than or equal to + * FIFO DEPTH unless repeated start is selected + */ + if (id->recv_count <= id->fifo_depth && + !id->bus_hold_flag) + cdns_i2c_clear_bus_hold(id); + + } else { + dev_err(id->adap.dev.parent, + "xfer_size reg rollover. xfer aborted!\n"); + id->err_status |= CDNS_I2C_IXR_TO; + break; + } + + if (cdns_is_holdquirk(id, updatetx)) + break; + } + + /* + * The controller sends NACK to the slave when transfer size + * register reaches zero without considering the HOLD bit. + * This workaround is implemented for large data transfers to + * maintain transfer size non-zero while performing a large + * receive operation. + */ + if (cdns_is_holdquirk(id, updatetx)) { + /* wait while fifo is full */ + while (cdns_i2c_readreg(CDNS_I2C_XFER_SIZE_OFFSET) != + (id->curr_recv_count - id->fifo_depth)) + ; + + /* + * Check number of bytes to be received against maximum + * transfer size and update register accordingly. + */ + if (((int)(id->recv_count) - id->fifo_depth) > + id->transfer_size) { + cdns_i2c_writereg(id->transfer_size, + CDNS_I2C_XFER_SIZE_OFFSET); + id->curr_recv_count = id->transfer_size + + id->fifo_depth; + } else { + cdns_i2c_writereg(id->recv_count - + id->fifo_depth, + CDNS_I2C_XFER_SIZE_OFFSET); + id->curr_recv_count = id->recv_count; + } + } + + /* Clear hold (if not repeated start) and signal completion */ + if ((isr_status & CDNS_I2C_IXR_COMP) && !id->recv_count) { + if (!id->bus_hold_flag) + cdns_i2c_clear_bus_hold(id); + done_flag = 1; + } + + status = IRQ_HANDLED; + } + + /* When sending, handle transfer complete interrupt */ + if ((isr_status & CDNS_I2C_IXR_COMP) && !id->p_recv_buf) { + /* + * If there is more data to be sent, calculate the + * space available in FIFO and fill with that many bytes. + */ + if (id->send_count) { + avail_bytes = id->fifo_depth - + cdns_i2c_readreg(CDNS_I2C_XFER_SIZE_OFFSET); + if (id->send_count > avail_bytes) + bytes_to_send = avail_bytes; + else + bytes_to_send = id->send_count; + + while (bytes_to_send--) { + cdns_i2c_writereg( + (*(id->p_send_buf)++), + CDNS_I2C_DATA_OFFSET); + id->send_count--; + } + } else { + /* + * Signal the completion of transaction and + * clear the hold bus bit if there are no + * further messages to be processed. + */ + done_flag = 1; + } + if (!id->send_count && !id->bus_hold_flag) + cdns_i2c_clear_bus_hold(id); + + status = IRQ_HANDLED; + } + + /* Update the status for errors */ + id->err_status |= isr_status & CDNS_I2C_IXR_ERR_INTR_MASK; + if (id->err_status) + status = IRQ_HANDLED; + + if (done_flag) + complete(&id->xfer_done); + + return status; +} + +/** + * cdns_i2c_isr - Interrupt handler for the I2C device + * @irq: irq number for the I2C device + * @ptr: void pointer to cdns_i2c structure + * + * This function passes the control to slave/master based on current role of + * i2c controller. + * + * Return: IRQ_HANDLED always + */ +static irqreturn_t cdns_i2c_isr(int irq, void *ptr) +{ +#if IS_ENABLED(CONFIG_I2C_SLAVE) + struct cdns_i2c *id = ptr; + + if (id->dev_mode == CDNS_I2C_MODE_SLAVE) + return cdns_i2c_slave_isr(ptr); +#endif + return cdns_i2c_master_isr(ptr); +} + +/** + * cdns_i2c_mrecv - Prepare and start a master receive operation + * @id: pointer to the i2c device structure + */ +static void cdns_i2c_mrecv(struct cdns_i2c *id) +{ + unsigned int ctrl_reg; + unsigned int isr_status; + unsigned long flags; + bool hold_clear = false; + bool irq_save = false; + + u32 addr; + + id->p_recv_buf = id->p_msg->buf; + id->recv_count = id->p_msg->len; + + /* Put the controller in master receive mode and clear the FIFO */ + ctrl_reg = cdns_i2c_readreg(CDNS_I2C_CR_OFFSET); + ctrl_reg |= CDNS_I2C_CR_RW | CDNS_I2C_CR_CLR_FIFO; + + /* + * Receive up to I2C_SMBUS_BLOCK_MAX data bytes, plus one message length + * byte, plus one checksum byte if PEC is enabled. p_msg->len will be 2 if + * PEC is enabled, otherwise 1. + */ + if (id->p_msg->flags & I2C_M_RECV_LEN) + id->recv_count = I2C_SMBUS_BLOCK_MAX + id->p_msg->len; + + id->curr_recv_count = id->recv_count; + + /* + * Check for the message size against FIFO depth and set the + * 'hold bus' bit if it is greater than FIFO depth. + */ + if (id->recv_count > id->fifo_depth) + ctrl_reg |= CDNS_I2C_CR_HOLD; + + cdns_i2c_writereg(ctrl_reg, CDNS_I2C_CR_OFFSET); + + /* Clear the interrupts in interrupt status register */ + isr_status = cdns_i2c_readreg(CDNS_I2C_ISR_OFFSET); + cdns_i2c_writereg(isr_status, CDNS_I2C_ISR_OFFSET); + + /* + * The no. of bytes to receive is checked against the limit of + * max transfer size. Set transfer size register with no of bytes + * receive if it is less than transfer size and transfer size if + * it is more. Enable the interrupts. + */ + if (id->recv_count > id->transfer_size) { + cdns_i2c_writereg(id->transfer_size, + CDNS_I2C_XFER_SIZE_OFFSET); + id->curr_recv_count = id->transfer_size; + } else { + cdns_i2c_writereg(id->recv_count, CDNS_I2C_XFER_SIZE_OFFSET); + } + + /* Determine hold_clear based on number of bytes to receive and hold flag */ + if (!id->bus_hold_flag && id->recv_count <= id->fifo_depth) { + if (ctrl_reg & CDNS_I2C_CR_HOLD) { + hold_clear = true; + if (id->quirks & CDNS_I2C_BROKEN_HOLD_BIT) + irq_save = true; + } + } + + addr = id->p_msg->addr; + addr &= CDNS_I2C_ADDR_MASK; + + if (hold_clear) { + ctrl_reg &= ~CDNS_I2C_CR_HOLD; + /* + * In case of Xilinx Zynq SOC, clear the HOLD bit before transfer size + * register reaches '0'. This is an IP bug which causes transfer size + * register overflow to 0xFF. To satisfy this timing requirement, + * disable the interrupts on current processor core between register + * writes to slave address register and control register. + */ + if (irq_save) + local_irq_save(flags); + + cdns_i2c_writereg(addr, CDNS_I2C_ADDR_OFFSET); + cdns_i2c_writereg(ctrl_reg, CDNS_I2C_CR_OFFSET); + /* Read it back to avoid bufferring and make sure write happens */ + cdns_i2c_readreg(CDNS_I2C_CR_OFFSET); + + if (irq_save) + local_irq_restore(flags); + } else { + cdns_i2c_writereg(addr, CDNS_I2C_ADDR_OFFSET); + } + + cdns_i2c_writereg(CDNS_I2C_ENABLED_INTR_MASK, CDNS_I2C_IER_OFFSET); +} + +/** + * cdns_i2c_msend - Prepare and start a master send operation + * @id: pointer to the i2c device + */ +static void cdns_i2c_msend(struct cdns_i2c *id) +{ + unsigned int avail_bytes; + unsigned int bytes_to_send; + unsigned int ctrl_reg; + unsigned int isr_status; + + id->p_recv_buf = NULL; + id->p_send_buf = id->p_msg->buf; + id->send_count = id->p_msg->len; + + /* Set the controller in Master transmit mode and clear the FIFO. */ + ctrl_reg = cdns_i2c_readreg(CDNS_I2C_CR_OFFSET); + ctrl_reg &= ~CDNS_I2C_CR_RW; + ctrl_reg |= CDNS_I2C_CR_CLR_FIFO; + + /* + * Check for the message size against FIFO depth and set the + * 'hold bus' bit if it is greater than FIFO depth. + */ + if (id->send_count > id->fifo_depth) + ctrl_reg |= CDNS_I2C_CR_HOLD; + cdns_i2c_writereg(ctrl_reg, CDNS_I2C_CR_OFFSET); + + /* Clear the interrupts in interrupt status register. */ + isr_status = cdns_i2c_readreg(CDNS_I2C_ISR_OFFSET); + cdns_i2c_writereg(isr_status, CDNS_I2C_ISR_OFFSET); + + /* + * Calculate the space available in FIFO. Check the message length + * against the space available, and fill the FIFO accordingly. + * Enable the interrupts. + */ + avail_bytes = id->fifo_depth - + cdns_i2c_readreg(CDNS_I2C_XFER_SIZE_OFFSET); + + if (id->send_count > avail_bytes) + bytes_to_send = avail_bytes; + else + bytes_to_send = id->send_count; + + while (bytes_to_send--) { + cdns_i2c_writereg((*(id->p_send_buf)++), CDNS_I2C_DATA_OFFSET); + id->send_count--; + } + + /* + * Clear the bus hold flag if there is no more data + * and if it is the last message. + */ + if (!id->bus_hold_flag && !id->send_count) + cdns_i2c_clear_bus_hold(id); + /* Set the slave address in address register - triggers operation. */ + cdns_i2c_writereg(id->p_msg->addr & CDNS_I2C_ADDR_MASK, + CDNS_I2C_ADDR_OFFSET); + + cdns_i2c_writereg(CDNS_I2C_ENABLED_INTR_MASK, CDNS_I2C_IER_OFFSET); +} + +/** + * cdns_i2c_master_reset - Reset the interface + * @adap: pointer to the i2c adapter driver instance + * + * This function cleanup the fifos, clear the hold bit and status + * and disable the interrupts. + */ +static void cdns_i2c_master_reset(struct i2c_adapter *adap) +{ + struct cdns_i2c *id = adap->algo_data; + u32 regval; + + /* Disable the interrupts */ + cdns_i2c_writereg(CDNS_I2C_IXR_ALL_INTR_MASK, CDNS_I2C_IDR_OFFSET); + /* Clear the hold bit and fifos */ + regval = cdns_i2c_readreg(CDNS_I2C_CR_OFFSET); + regval &= ~CDNS_I2C_CR_HOLD; + regval |= CDNS_I2C_CR_CLR_FIFO; + cdns_i2c_writereg(regval, CDNS_I2C_CR_OFFSET); + /* Update the transfercount register to zero */ + cdns_i2c_writereg(0, CDNS_I2C_XFER_SIZE_OFFSET); + /* Clear the interrupt status register */ + regval = cdns_i2c_readreg(CDNS_I2C_ISR_OFFSET); + cdns_i2c_writereg(regval, CDNS_I2C_ISR_OFFSET); + /* Clear the status register */ + regval = cdns_i2c_readreg(CDNS_I2C_SR_OFFSET); + cdns_i2c_writereg(regval, CDNS_I2C_SR_OFFSET); +} + +static int cdns_i2c_process_msg(struct cdns_i2c *id, struct i2c_msg *msg, + struct i2c_adapter *adap) +{ + unsigned long time_left, msg_timeout; + u32 reg; + + id->p_msg = msg; + id->err_status = 0; + reinit_completion(&id->xfer_done); + + /* Check for the TEN Bit mode on each msg */ + reg = cdns_i2c_readreg(CDNS_I2C_CR_OFFSET); + if (msg->flags & I2C_M_TEN) { + if (reg & CDNS_I2C_CR_NEA) + cdns_i2c_writereg(reg & ~CDNS_I2C_CR_NEA, + CDNS_I2C_CR_OFFSET); + } else { + if (!(reg & CDNS_I2C_CR_NEA)) + cdns_i2c_writereg(reg | CDNS_I2C_CR_NEA, + CDNS_I2C_CR_OFFSET); + } + + /* Check for the R/W flag on each msg */ + if (msg->flags & I2C_M_RD) + cdns_i2c_mrecv(id); + else + cdns_i2c_msend(id); + + /* Minimal time to execute this message */ + msg_timeout = msecs_to_jiffies((1000 * msg->len * BITS_PER_BYTE) / id->i2c_clk); + /* Plus some wiggle room */ + msg_timeout += msecs_to_jiffies(500); + + if (msg_timeout < adap->timeout) + msg_timeout = adap->timeout; + + /* Wait for the signal of completion */ + time_left = wait_for_completion_timeout(&id->xfer_done, msg_timeout); + if (time_left == 0) { + cdns_i2c_master_reset(adap); + dev_err(id->adap.dev.parent, + "timeout waiting on completion\n"); + return -ETIMEDOUT; + } + + cdns_i2c_writereg(CDNS_I2C_IXR_ALL_INTR_MASK, + CDNS_I2C_IDR_OFFSET); + + /* If it is bus arbitration error, try again */ + if (id->err_status & CDNS_I2C_IXR_ARB_LOST) + return -EAGAIN; + + if (msg->flags & I2C_M_RECV_LEN) + msg->len += min_t(unsigned int, msg->buf[0], I2C_SMBUS_BLOCK_MAX); + + return 0; +} + +/** + * cdns_i2c_master_xfer - The main i2c transfer function + * @adap: pointer to the i2c adapter driver instance + * @msgs: pointer to the i2c message structure + * @num: the number of messages to transfer + * + * Initiates the send/recv activity based on the transfer message received. + * + * Return: number of msgs processed on success, negative error otherwise + */ +static int cdns_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + int ret, count; + u32 reg; + struct cdns_i2c *id = adap->algo_data; + bool hold_quirk; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + bool change_role = false; +#endif + + ret = pm_runtime_resume_and_get(id->dev); + if (ret < 0) + return ret; + +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* Check i2c operating mode and switch if possible */ + if (id->dev_mode == CDNS_I2C_MODE_SLAVE) { + if (id->slave_state != CDNS_I2C_SLAVE_STATE_IDLE) { + ret = -EAGAIN; + goto out; + } + + /* Set mode to master */ + cdns_i2c_set_mode(CDNS_I2C_MODE_MASTER, id); + + /* Mark flag to change role once xfer is completed */ + change_role = true; + } +#endif + + /* Check if the bus is free */ + + ret = readl_relaxed_poll_timeout(id->membase + CDNS_I2C_SR_OFFSET, + reg, + !(reg & CDNS_I2C_SR_BA), + CDNS_I2C_POLL_US, CDNS_I2C_TIMEOUT_US); + if (ret) { + ret = -EAGAIN; + if (id->adap.bus_recovery_info) + i2c_recover_bus(adap); + goto out; + } + + hold_quirk = !!(id->quirks & CDNS_I2C_BROKEN_HOLD_BIT); + /* + * Set the flag to one when multiple messages are to be + * processed with a repeated start. + */ + if (num > 1) { + /* + * This controller does not give completion interrupt after a + * master receive message if HOLD bit is set (repeated start), + * resulting in SW timeout. Hence, if a receive message is + * followed by any other message, an error is returned + * indicating that this sequence is not supported. + */ + for (count = 0; (count < num - 1 && hold_quirk); count++) { + if (msgs[count].flags & I2C_M_RD) { + dev_warn(adap->dev.parent, + "Can't do repeated start after a receive message\n"); + ret = -EOPNOTSUPP; + goto out; + } + } + id->bus_hold_flag = 1; + reg = cdns_i2c_readreg(CDNS_I2C_CR_OFFSET); + reg |= CDNS_I2C_CR_HOLD; + cdns_i2c_writereg(reg, CDNS_I2C_CR_OFFSET); + } else { + id->bus_hold_flag = 0; + } + + /* Process the msg one by one */ + for (count = 0; count < num; count++, msgs++) { + if (count == (num - 1)) + id->bus_hold_flag = 0; + + ret = cdns_i2c_process_msg(id, msgs, adap); + if (ret) + goto out; + + /* Report the other error interrupts to application */ + if (id->err_status) { + cdns_i2c_master_reset(adap); + + if (id->err_status & CDNS_I2C_IXR_NACK) { + ret = -ENXIO; + goto out; + } + ret = -EIO; + goto out; + } + } + + ret = num; + +out: + +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* Switch i2c mode to slave */ + if (change_role) + cdns_i2c_set_mode(CDNS_I2C_MODE_SLAVE, id); +#endif + + pm_runtime_mark_last_busy(id->dev); + pm_runtime_put_autosuspend(id->dev); + return ret; +} + +/** + * cdns_i2c_func - Returns the supported features of the I2C driver + * @adap: pointer to the i2c adapter structure + * + * Return: 32 bit value, each bit corresponding to a feature + */ +static u32 cdns_i2c_func(struct i2c_adapter *adap) +{ + u32 func = I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | + (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | + I2C_FUNC_SMBUS_BLOCK_DATA; + +#if IS_ENABLED(CONFIG_I2C_SLAVE) + func |= I2C_FUNC_SLAVE; +#endif + + return func; +} + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +static int cdns_reg_slave(struct i2c_client *slave) +{ + int ret; + struct cdns_i2c *id = container_of(slave->adapter, struct cdns_i2c, + adap); + + if (id->slave) + return -EBUSY; + + if (slave->flags & I2C_CLIENT_TEN) + return -EAFNOSUPPORT; + + ret = pm_runtime_resume_and_get(id->dev); + if (ret < 0) + return ret; + + /* Store slave information */ + id->slave = slave; + + /* Enable I2C slave */ + cdns_i2c_set_mode(CDNS_I2C_MODE_SLAVE, id); + + return 0; +} + +static int cdns_unreg_slave(struct i2c_client *slave) +{ + struct cdns_i2c *id = container_of(slave->adapter, struct cdns_i2c, + adap); + + pm_runtime_put(id->dev); + + /* Remove slave information */ + id->slave = NULL; + + /* Enable I2C master */ + cdns_i2c_set_mode(CDNS_I2C_MODE_MASTER, id); + + return 0; +} +#endif + +static const struct i2c_algorithm cdns_i2c_algo = { + .master_xfer = cdns_i2c_master_xfer, + .functionality = cdns_i2c_func, +#if IS_ENABLED(CONFIG_I2C_SLAVE) + .reg_slave = cdns_reg_slave, + .unreg_slave = cdns_unreg_slave, +#endif +}; + +/** + * cdns_i2c_calc_divs - Calculate clock dividers + * @f: I2C clock frequency + * @input_clk: Input clock frequency + * @a: First divider (return value) + * @b: Second divider (return value) + * + * f is used as input and output variable. As input it is used as target I2C + * frequency. On function exit f holds the actually resulting I2C frequency. + * + * Return: 0 on success, negative errno otherwise. + */ +static int cdns_i2c_calc_divs(unsigned long *f, unsigned long input_clk, + unsigned int *a, unsigned int *b) +{ + unsigned long fscl = *f, best_fscl = *f, actual_fscl, temp; + unsigned int div_a, div_b, calc_div_a = 0, calc_div_b = 0; + unsigned int last_error, current_error; + + /* calculate (divisor_a+1) x (divisor_b+1) */ + temp = input_clk / (22 * fscl); + + /* + * If the calculated value is negative or 0, the fscl input is out of + * range. Return error. + */ + if (!temp || (temp > (CDNS_I2C_DIVA_MAX * CDNS_I2C_DIVB_MAX))) + return -EINVAL; + + last_error = -1; + for (div_a = 0; div_a < CDNS_I2C_DIVA_MAX; div_a++) { + div_b = DIV_ROUND_UP(input_clk, 22 * fscl * (div_a + 1)); + + if ((div_b < 1) || (div_b > CDNS_I2C_DIVB_MAX)) + continue; + div_b--; + + actual_fscl = input_clk / (22 * (div_a + 1) * (div_b + 1)); + + if (actual_fscl > fscl) + continue; + + current_error = fscl - actual_fscl; + + if (last_error > current_error) { + calc_div_a = div_a; + calc_div_b = div_b; + best_fscl = actual_fscl; + last_error = current_error; + } + } + + *a = calc_div_a; + *b = calc_div_b; + *f = best_fscl; + + return 0; +} + +/** + * cdns_i2c_setclk - This function sets the serial clock rate for the I2C device + * @clk_in: I2C clock input frequency in Hz + * @id: Pointer to the I2C device structure + * + * The device must be idle rather than busy transferring data before setting + * these device options. + * The data rate is set by values in the control register. + * The formula for determining the correct register values is + * Fscl = Fpclk/(22 x (divisor_a+1) x (divisor_b+1)) + * See the hardware data sheet for a full explanation of setting the serial + * clock rate. The clock can not be faster than the input clock divide by 22. + * The two most common clock rates are 100KHz and 400KHz. + * + * Return: 0 on success, negative error otherwise + */ +static int cdns_i2c_setclk(unsigned long clk_in, struct cdns_i2c *id) +{ + unsigned int div_a, div_b; + unsigned int ctrl_reg; + int ret = 0; + unsigned long fscl = id->i2c_clk; + + ret = cdns_i2c_calc_divs(&fscl, clk_in, &div_a, &div_b); + if (ret) + return ret; + + ctrl_reg = id->ctrl_reg; + ctrl_reg &= ~(CDNS_I2C_CR_DIVA_MASK | CDNS_I2C_CR_DIVB_MASK); + ctrl_reg |= ((div_a << CDNS_I2C_CR_DIVA_SHIFT) | + (div_b << CDNS_I2C_CR_DIVB_SHIFT)); + id->ctrl_reg = ctrl_reg; + cdns_i2c_writereg(ctrl_reg, CDNS_I2C_CR_OFFSET); +#if IS_ENABLED(CONFIG_I2C_SLAVE) + id->ctrl_reg_diva_divb = ctrl_reg & (CDNS_I2C_CR_DIVA_MASK | + CDNS_I2C_CR_DIVB_MASK); +#endif + return 0; +} + +/** + * cdns_i2c_clk_notifier_cb - Clock rate change callback + * @nb: Pointer to notifier block + * @event: Notification reason + * @data: Pointer to notification data object + * + * This function is called when the cdns_i2c input clock frequency changes. + * The callback checks whether a valid bus frequency can be generated after the + * change. If so, the change is acknowledged, otherwise the change is aborted. + * New dividers are written to the HW in the pre- or post change notification + * depending on the scaling direction. + * + * Return: NOTIFY_STOP if the rate change should be aborted, NOTIFY_OK + * to acknowledge the change, NOTIFY_DONE if the notification is + * considered irrelevant. + */ +static int cdns_i2c_clk_notifier_cb(struct notifier_block *nb, unsigned long + event, void *data) +{ + struct clk_notifier_data *ndata = data; + struct cdns_i2c *id = to_cdns_i2c(nb); + + if (pm_runtime_suspended(id->dev)) + return NOTIFY_OK; + + switch (event) { + case PRE_RATE_CHANGE: + { + unsigned long input_clk = ndata->new_rate; + unsigned long fscl = id->i2c_clk; + unsigned int div_a, div_b; + int ret; + + ret = cdns_i2c_calc_divs(&fscl, input_clk, &div_a, &div_b); + if (ret) { + dev_warn(id->adap.dev.parent, + "clock rate change rejected\n"); + return NOTIFY_STOP; + } + + /* scale up */ + if (ndata->new_rate > ndata->old_rate) + cdns_i2c_setclk(ndata->new_rate, id); + + return NOTIFY_OK; + } + case POST_RATE_CHANGE: + id->input_clk = ndata->new_rate; + /* scale down */ + if (ndata->new_rate < ndata->old_rate) + cdns_i2c_setclk(ndata->new_rate, id); + return NOTIFY_OK; + case ABORT_RATE_CHANGE: + /* scale up */ + if (ndata->new_rate > ndata->old_rate) + cdns_i2c_setclk(ndata->old_rate, id); + return NOTIFY_OK; + default: + return NOTIFY_DONE; + } +} + +/** + * cdns_i2c_runtime_suspend - Runtime suspend method for the driver + * @dev: Address of the platform_device structure + * + * Put the driver into low power mode. + * + * Return: 0 always + */ +static int __maybe_unused cdns_i2c_runtime_suspend(struct device *dev) +{ + struct cdns_i2c *xi2c = dev_get_drvdata(dev); + + clk_disable(xi2c->clk); + + return 0; +} + +/** + * cdns_i2c_init - Controller initialisation + * @id: Device private data structure + * + * Initialise the i2c controller. + * + */ +static void cdns_i2c_init(struct cdns_i2c *id) +{ + cdns_i2c_writereg(id->ctrl_reg, CDNS_I2C_CR_OFFSET); + /* + * Cadence I2C controller has a bug wherein it generates + * invalid read transaction after HW timeout in master receiver mode. + * HW timeout is not used by this driver and the interrupt is disabled. + * But the feature itself cannot be disabled. Hence maximum value + * is written to this register to reduce the chances of error. + */ + cdns_i2c_writereg(CDNS_I2C_TIMEOUT_MAX, CDNS_I2C_TIME_OUT_OFFSET); +} + +/** + * cdns_i2c_runtime_resume - Runtime resume + * @dev: Address of the platform_device structure + * + * Runtime resume callback. + * + * Return: 0 on success and error value on error + */ +static int __maybe_unused cdns_i2c_runtime_resume(struct device *dev) +{ + struct cdns_i2c *xi2c = dev_get_drvdata(dev); + int ret; + + ret = clk_enable(xi2c->clk); + if (ret) { + dev_err(dev, "Cannot enable clock.\n"); + return ret; + } + cdns_i2c_init(xi2c); + + return 0; +} + +static const struct dev_pm_ops cdns_i2c_dev_pm_ops = { + SET_RUNTIME_PM_OPS(cdns_i2c_runtime_suspend, + cdns_i2c_runtime_resume, NULL) +}; + +static const struct cdns_platform_data r1p10_i2c_def = { + .quirks = CDNS_I2C_BROKEN_HOLD_BIT, +}; + +static const struct of_device_id cdns_i2c_of_match[] = { + { .compatible = "cdns,i2c-r1p10", .data = &r1p10_i2c_def }, + { .compatible = "cdns,i2c-r1p14",}, + { /* end of table */ } +}; +MODULE_DEVICE_TABLE(of, cdns_i2c_of_match); + +/** + * cdns_i2c_detect_transfer_size - Detect the maximum transfer size supported + * @id: Device private data structure + * + * Detect the maximum transfer size that is supported by this instance of the + * Cadence I2C controller. + */ +static void cdns_i2c_detect_transfer_size(struct cdns_i2c *id) +{ + u32 val; + + /* + * Writing to the transfer size register is only possible if these two bits + * are set in the control register. + */ + cdns_i2c_writereg(CDNS_I2C_CR_MS | CDNS_I2C_CR_RW, CDNS_I2C_CR_OFFSET); + + /* + * The number of writable bits of the transfer size register can be between + * 4 and 8. This is a controlled through a synthesis parameter of the IP + * core and can vary from instance to instance. The unused MSBs always read + * back as 0. Writing 0xff and then reading the value back will report the + * maximum supported transfer size. + */ + cdns_i2c_writereg(CDNS_I2C_MAX_TRANSFER_SIZE, CDNS_I2C_XFER_SIZE_OFFSET); + val = cdns_i2c_readreg(CDNS_I2C_XFER_SIZE_OFFSET); + id->transfer_size = CDNS_I2C_TRANSFER_SIZE(val); + cdns_i2c_writereg(0, CDNS_I2C_XFER_SIZE_OFFSET); + cdns_i2c_writereg(0, CDNS_I2C_CR_OFFSET); +} + +/** + * cdns_i2c_probe - Platform registration call + * @pdev: Handle to the platform device structure + * + * This function does all the memory allocation and registration for the i2c + * device. User can modify the address mode to 10 bit address mode using the + * ioctl call with option I2C_TENBIT. + * + * Return: 0 on success, negative error otherwise + */ +static int cdns_i2c_probe(struct platform_device *pdev) +{ + struct resource *r_mem; + struct cdns_i2c *id; + int ret, irq; + const struct of_device_id *match; + + id = devm_kzalloc(&pdev->dev, sizeof(*id), GFP_KERNEL); + if (!id) + return -ENOMEM; + + id->dev = &pdev->dev; + platform_set_drvdata(pdev, id); + + match = of_match_node(cdns_i2c_of_match, pdev->dev.of_node); + if (match && match->data) { + const struct cdns_platform_data *data = match->data; + id->quirks = data->quirks; + } + + id->rinfo.pinctrl = devm_pinctrl_get(&pdev->dev); + if (IS_ERR(id->rinfo.pinctrl)) { + int err = PTR_ERR(id->rinfo.pinctrl); + + dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n"); + if (err != -ENODEV) + return err; + } else { + id->adap.bus_recovery_info = &id->rinfo; + } + + id->membase = devm_platform_get_and_ioremap_resource(pdev, 0, &r_mem); + if (IS_ERR(id->membase)) + return PTR_ERR(id->membase); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + id->adap.owner = THIS_MODULE; + id->adap.dev.of_node = pdev->dev.of_node; + id->adap.algo = &cdns_i2c_algo; + id->adap.timeout = CDNS_I2C_TIMEOUT; + id->adap.retries = 3; /* Default retry value. */ + id->adap.algo_data = id; + id->adap.dev.parent = &pdev->dev; + init_completion(&id->xfer_done); + snprintf(id->adap.name, sizeof(id->adap.name), + "Cadence I2C at %08lx", (unsigned long)r_mem->start); + + id->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(id->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(id->clk), + "input clock not found.\n"); + + id->reset = devm_reset_control_get_optional_shared(&pdev->dev, NULL); + if (IS_ERR(id->reset)) + return dev_err_probe(&pdev->dev, PTR_ERR(id->reset), + "Failed to request reset.\n"); + + ret = clk_prepare_enable(id->clk); + if (ret) + dev_err(&pdev->dev, "Unable to enable clock.\n"); + + ret = reset_control_deassert(id->reset); + if (ret) { + dev_err_probe(&pdev->dev, ret, + "Failed to de-assert reset.\n"); + goto err_clk_dis; + } + + pm_runtime_set_autosuspend_delay(id->dev, CNDS_I2C_PM_TIMEOUT); + pm_runtime_use_autosuspend(id->dev); + pm_runtime_set_active(id->dev); + pm_runtime_enable(id->dev); + + id->clk_rate_change_nb.notifier_call = cdns_i2c_clk_notifier_cb; + if (clk_notifier_register(id->clk, &id->clk_rate_change_nb)) + dev_warn(&pdev->dev, "Unable to register clock notifier.\n"); + id->input_clk = clk_get_rate(id->clk); + + ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency", + &id->i2c_clk); + if (ret || (id->i2c_clk > I2C_MAX_FAST_MODE_FREQ)) + id->i2c_clk = I2C_MAX_STANDARD_MODE_FREQ; + +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* Set initial mode to master */ + id->dev_mode = CDNS_I2C_MODE_MASTER; + id->slave_state = CDNS_I2C_SLAVE_STATE_IDLE; +#endif + id->ctrl_reg = CDNS_I2C_CR_ACK_EN | CDNS_I2C_CR_NEA | CDNS_I2C_CR_MS; + + id->fifo_depth = CDNS_I2C_FIFO_DEPTH_DEFAULT; + of_property_read_u32(pdev->dev.of_node, "fifo-depth", &id->fifo_depth); + + cdns_i2c_detect_transfer_size(id); + + ret = cdns_i2c_setclk(id->input_clk, id); + if (ret) { + dev_err(&pdev->dev, "invalid SCL clock: %u Hz\n", id->i2c_clk); + ret = -EINVAL; + goto err_clk_notifier_unregister; + } + + ret = devm_request_irq(&pdev->dev, irq, cdns_i2c_isr, 0, + DRIVER_NAME, id); + if (ret) { + dev_err(&pdev->dev, "cannot get irq %d\n", irq); + goto err_clk_notifier_unregister; + } + cdns_i2c_init(id); + + ret = i2c_add_adapter(&id->adap); + if (ret < 0) + goto err_clk_notifier_unregister; + + dev_info(&pdev->dev, "%u kHz mmio %08lx irq %d\n", + id->i2c_clk / 1000, (unsigned long)r_mem->start, irq); + + return 0; + +err_clk_notifier_unregister: + clk_notifier_unregister(id->clk, &id->clk_rate_change_nb); + reset_control_assert(id->reset); +err_clk_dis: + clk_disable_unprepare(id->clk); + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + return ret; +} + +/** + * cdns_i2c_remove - Unregister the device after releasing the resources + * @pdev: Handle to the platform device structure + * + * This function frees all the resources allocated to the device. + * + * Return: 0 always + */ +static void cdns_i2c_remove(struct platform_device *pdev) +{ + struct cdns_i2c *id = platform_get_drvdata(pdev); + + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_dont_use_autosuspend(&pdev->dev); + + i2c_del_adapter(&id->adap); + clk_notifier_unregister(id->clk, &id->clk_rate_change_nb); + reset_control_assert(id->reset); + clk_disable_unprepare(id->clk); +} + +static struct platform_driver cdns_i2c_drv = { + .driver = { + .name = DRIVER_NAME, + .of_match_table = cdns_i2c_of_match, + .pm = &cdns_i2c_dev_pm_ops, + }, + .probe = cdns_i2c_probe, + .remove_new = cdns_i2c_remove, +}; + +module_platform_driver(cdns_i2c_drv); + +MODULE_AUTHOR("Xilinx Inc."); +MODULE_DESCRIPTION("Cadence I2C bus driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-cbus-gpio.c b/drivers/i2c/busses/i2c-cbus-gpio.c new file mode 100644 index 000000000..fdc1758a3 --- /dev/null +++ b/drivers/i2c/busses/i2c-cbus-gpio.c @@ -0,0 +1,282 @@ +/* + * CBUS I2C driver for Nokia Internet Tablets. + * + * Copyright (C) 2004-2010 Nokia Corporation + * + * Based on code written by Juha Yrjölä, David Weinehall, Mikko Ylinen and + * Felipe Balbi. Converted to I2C driver by Aaro Koskinen. + * + * This file is subject to the terms and conditions of the GNU General + * Public License. See the file "COPYING" in the main directory of this + * archive for more details. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/io.h> +#include <linux/i2c.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/gpio/consumer.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> + +/* + * Bit counts are derived from Nokia implementation. These should be checked + * if other CBUS implementations appear. + */ +#define CBUS_ADDR_BITS 3 +#define CBUS_REG_BITS 5 + +struct cbus_host { + spinlock_t lock; /* host lock */ + struct device *dev; + struct gpio_desc *clk; + struct gpio_desc *dat; + struct gpio_desc *sel; +}; + +/** + * cbus_send_bit - sends one bit over the bus + * @host: the host we're using + * @bit: one bit of information to send + */ +static void cbus_send_bit(struct cbus_host *host, unsigned bit) +{ + gpiod_set_value(host->dat, bit ? 1 : 0); + gpiod_set_value(host->clk, 1); + gpiod_set_value(host->clk, 0); +} + +/** + * cbus_send_data - sends @len amount of data over the bus + * @host: the host we're using + * @data: the data to send + * @len: size of the transfer + */ +static void cbus_send_data(struct cbus_host *host, unsigned data, unsigned len) +{ + int i; + + for (i = len; i > 0; i--) + cbus_send_bit(host, data & (1 << (i - 1))); +} + +/** + * cbus_receive_bit - receives one bit from the bus + * @host: the host we're using + */ +static int cbus_receive_bit(struct cbus_host *host) +{ + int ret; + + gpiod_set_value(host->clk, 1); + ret = gpiod_get_value(host->dat); + gpiod_set_value(host->clk, 0); + return ret; +} + +/** + * cbus_receive_word - receives 16-bit word from the bus + * @host: the host we're using + */ +static int cbus_receive_word(struct cbus_host *host) +{ + int ret = 0; + int i; + + for (i = 16; i > 0; i--) { + int bit = cbus_receive_bit(host); + + if (bit < 0) + return bit; + + if (bit) + ret |= 1 << (i - 1); + } + return ret; +} + +/** + * cbus_transfer - transfers data over the bus + * @host: the host we're using + * @rw: read/write flag + * @dev: device address + * @reg: register address + * @data: if @rw == I2C_SBUS_WRITE data to send otherwise 0 + */ +static int cbus_transfer(struct cbus_host *host, char rw, unsigned dev, + unsigned reg, unsigned data) +{ + unsigned long flags; + int ret; + + /* We don't want interrupts disturbing our transfer */ + spin_lock_irqsave(&host->lock, flags); + + /* Reset state and start of transfer, SEL stays down during transfer */ + gpiod_set_value(host->sel, 0); + + /* Set the DAT pin to output */ + gpiod_direction_output(host->dat, 1); + + /* Send the device address */ + cbus_send_data(host, dev, CBUS_ADDR_BITS); + + /* Send the rw flag */ + cbus_send_bit(host, rw == I2C_SMBUS_READ); + + /* Send the register address */ + cbus_send_data(host, reg, CBUS_REG_BITS); + + if (rw == I2C_SMBUS_WRITE) { + cbus_send_data(host, data, 16); + ret = 0; + } else { + ret = gpiod_direction_input(host->dat); + if (ret) { + dev_dbg(host->dev, "failed setting direction\n"); + goto out; + } + gpiod_set_value(host->clk, 1); + + ret = cbus_receive_word(host); + if (ret < 0) { + dev_dbg(host->dev, "failed receiving data\n"); + goto out; + } + } + + /* Indicate end of transfer, SEL goes up until next transfer */ + gpiod_set_value(host->sel, 1); + gpiod_set_value(host->clk, 1); + gpiod_set_value(host->clk, 0); + +out: + spin_unlock_irqrestore(&host->lock, flags); + + return ret; +} + +static int cbus_i2c_smbus_xfer(struct i2c_adapter *adapter, + u16 addr, + unsigned short flags, + char read_write, + u8 command, + int size, + union i2c_smbus_data *data) +{ + struct cbus_host *chost = i2c_get_adapdata(adapter); + int ret; + + if (size != I2C_SMBUS_WORD_DATA) + return -EINVAL; + + ret = cbus_transfer(chost, read_write == I2C_SMBUS_READ, addr, + command, data->word); + if (ret < 0) + return ret; + + if (read_write == I2C_SMBUS_READ) + data->word = ret; + + return 0; +} + +static u32 cbus_i2c_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_READ_WORD_DATA | I2C_FUNC_SMBUS_WRITE_WORD_DATA; +} + +static const struct i2c_algorithm cbus_i2c_algo = { + .smbus_xfer = cbus_i2c_smbus_xfer, + .smbus_xfer_atomic = cbus_i2c_smbus_xfer, + .functionality = cbus_i2c_func, +}; + +static void cbus_i2c_remove(struct platform_device *pdev) +{ + struct i2c_adapter *adapter = platform_get_drvdata(pdev); + + i2c_del_adapter(adapter); +} + +static int cbus_i2c_probe(struct platform_device *pdev) +{ + struct i2c_adapter *adapter; + struct cbus_host *chost; + + adapter = devm_kzalloc(&pdev->dev, sizeof(struct i2c_adapter), + GFP_KERNEL); + if (!adapter) + return -ENOMEM; + + chost = devm_kzalloc(&pdev->dev, sizeof(*chost), GFP_KERNEL); + if (!chost) + return -ENOMEM; + + if (gpiod_count(&pdev->dev, NULL) != 3) + return -ENODEV; + chost->clk = devm_gpiod_get_index(&pdev->dev, NULL, 0, GPIOD_OUT_LOW); + if (IS_ERR(chost->clk)) + return PTR_ERR(chost->clk); + chost->dat = devm_gpiod_get_index(&pdev->dev, NULL, 1, GPIOD_IN); + if (IS_ERR(chost->dat)) + return PTR_ERR(chost->dat); + chost->sel = devm_gpiod_get_index(&pdev->dev, NULL, 2, GPIOD_OUT_HIGH); + if (IS_ERR(chost->sel)) + return PTR_ERR(chost->sel); + gpiod_set_consumer_name(chost->clk, "CBUS clk"); + gpiod_set_consumer_name(chost->dat, "CBUS dat"); + gpiod_set_consumer_name(chost->sel, "CBUS sel"); + + adapter->owner = THIS_MODULE; + adapter->class = I2C_CLASS_HWMON; + adapter->dev.parent = &pdev->dev; + adapter->dev.of_node = pdev->dev.of_node; + adapter->nr = pdev->id; + adapter->timeout = HZ; + adapter->algo = &cbus_i2c_algo; + strscpy(adapter->name, "CBUS I2C adapter", sizeof(adapter->name)); + + spin_lock_init(&chost->lock); + chost->dev = &pdev->dev; + + i2c_set_adapdata(adapter, chost); + platform_set_drvdata(pdev, adapter); + + return i2c_add_numbered_adapter(adapter); +} + +#if defined(CONFIG_OF) +static const struct of_device_id i2c_cbus_dt_ids[] = { + { .compatible = "i2c-cbus-gpio", }, + { } +}; +MODULE_DEVICE_TABLE(of, i2c_cbus_dt_ids); +#endif + +static struct platform_driver cbus_i2c_driver = { + .probe = cbus_i2c_probe, + .remove_new = cbus_i2c_remove, + .driver = { + .name = "i2c-cbus-gpio", + .of_match_table = of_match_ptr(i2c_cbus_dt_ids), + }, +}; +module_platform_driver(cbus_i2c_driver); + +MODULE_ALIAS("platform:i2c-cbus-gpio"); +MODULE_DESCRIPTION("CBUS I2C driver"); +MODULE_AUTHOR("Juha Yrjölä"); +MODULE_AUTHOR("David Weinehall"); +MODULE_AUTHOR("Mikko Ylinen"); +MODULE_AUTHOR("Felipe Balbi"); +MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-ccgx-ucsi.c b/drivers/i2c/busses/i2c-ccgx-ucsi.c new file mode 100644 index 000000000..092dc92de --- /dev/null +++ b/drivers/i2c/busses/i2c-ccgx-ucsi.c @@ -0,0 +1,30 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Instantiate UCSI device for Cypress CCGx Type-C controller. + * Derived from i2c-designware-pcidrv.c and i2c-nvidia-gpu.c. + */ + +#include <linux/i2c.h> +#include <linux/export.h> +#include <linux/module.h> +#include <linux/string.h> + +#include "i2c-ccgx-ucsi.h" + +struct software_node; + +struct i2c_client *i2c_new_ccgx_ucsi(struct i2c_adapter *adapter, int irq, + const struct software_node *swnode) +{ + struct i2c_board_info info = {}; + + strscpy(info.type, "ccgx-ucsi", sizeof(info.type)); + info.addr = 0x08; + info.irq = irq; + info.swnode = swnode; + + return i2c_new_client_device(adapter, &info); +} +EXPORT_SYMBOL_GPL(i2c_new_ccgx_ucsi); + +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-ccgx-ucsi.h b/drivers/i2c/busses/i2c-ccgx-ucsi.h new file mode 100644 index 000000000..739ac7a4b --- /dev/null +++ b/drivers/i2c/busses/i2c-ccgx-ucsi.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef __I2C_CCGX_UCSI_H_ +#define __I2C_CCGX_UCSI_H_ + +struct i2c_adapter; +struct i2c_client; +struct software_node; + +struct i2c_client *i2c_new_ccgx_ucsi(struct i2c_adapter *adapter, int irq, + const struct software_node *swnode); +#endif /* __I2C_CCGX_UCSI_H_ */ diff --git a/drivers/i2c/busses/i2c-cht-wc.c b/drivers/i2c/busses/i2c-cht-wc.c new file mode 100644 index 000000000..0209933b9 --- /dev/null +++ b/drivers/i2c/busses/i2c-cht-wc.c @@ -0,0 +1,559 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Intel CHT Whiskey Cove PMIC I2C Master driver + * Copyright (C) 2017 Hans de Goede <hdegoede@redhat.com> + * + * Based on various non upstream patches to support the CHT Whiskey Cove PMIC: + * Copyright (C) 2011 - 2014 Intel Corporation. All rights reserved. + */ + +#include <linux/acpi.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/mfd/intel_soc_pmic.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/power/bq24190_charger.h> +#include <linux/power/bq25890_charger.h> +#include <linux/slab.h> + +#define CHT_WC_I2C_CTRL 0x5e24 +#define CHT_WC_I2C_CTRL_WR BIT(0) +#define CHT_WC_I2C_CTRL_RD BIT(1) +#define CHT_WC_I2C_CLIENT_ADDR 0x5e25 +#define CHT_WC_I2C_REG_OFFSET 0x5e26 +#define CHT_WC_I2C_WRDATA 0x5e27 +#define CHT_WC_I2C_RDDATA 0x5e28 + +#define CHT_WC_EXTCHGRIRQ 0x6e0a +#define CHT_WC_EXTCHGRIRQ_CLIENT_IRQ BIT(0) +#define CHT_WC_EXTCHGRIRQ_WRITE_IRQ BIT(1) +#define CHT_WC_EXTCHGRIRQ_READ_IRQ BIT(2) +#define CHT_WC_EXTCHGRIRQ_NACK_IRQ BIT(3) +#define CHT_WC_EXTCHGRIRQ_ADAP_IRQMASK ((u8)GENMASK(3, 1)) +#define CHT_WC_EXTCHGRIRQ_MSK 0x6e17 + +struct cht_wc_i2c_adap { + struct i2c_adapter adapter; + wait_queue_head_t wait; + struct irq_chip irqchip; + struct mutex adap_lock; + struct mutex irqchip_lock; + struct regmap *regmap; + struct irq_domain *irq_domain; + struct i2c_client *client; + int client_irq; + u8 irq_mask; + u8 old_irq_mask; + int read_data; + bool io_error; + bool done; +}; + +static irqreturn_t cht_wc_i2c_adap_thread_handler(int id, void *data) +{ + struct cht_wc_i2c_adap *adap = data; + int ret, reg; + + mutex_lock(&adap->adap_lock); + + /* Read IRQs */ + ret = regmap_read(adap->regmap, CHT_WC_EXTCHGRIRQ, ®); + if (ret) { + dev_err(&adap->adapter.dev, "Error reading extchgrirq reg\n"); + mutex_unlock(&adap->adap_lock); + return IRQ_NONE; + } + + reg &= ~adap->irq_mask; + + /* Reads must be acked after reading the received data. */ + ret = regmap_read(adap->regmap, CHT_WC_I2C_RDDATA, &adap->read_data); + if (ret) + adap->io_error = true; + + /* + * Immediately ack IRQs, so that if new IRQs arrives while we're + * handling the previous ones our irq will re-trigger when we're done. + */ + ret = regmap_write(adap->regmap, CHT_WC_EXTCHGRIRQ, reg); + if (ret) + dev_err(&adap->adapter.dev, "Error writing extchgrirq reg\n"); + + if (reg & CHT_WC_EXTCHGRIRQ_ADAP_IRQMASK) { + adap->io_error |= !!(reg & CHT_WC_EXTCHGRIRQ_NACK_IRQ); + adap->done = true; + } + + mutex_unlock(&adap->adap_lock); + + if (reg & CHT_WC_EXTCHGRIRQ_ADAP_IRQMASK) + wake_up(&adap->wait); + + /* + * Do NOT use handle_nested_irq here, the client irq handler will + * likely want to do i2c transfers and the i2c controller uses this + * interrupt handler as well, so running the client irq handler from + * this thread will cause things to lock up. + */ + if (reg & CHT_WC_EXTCHGRIRQ_CLIENT_IRQ) + generic_handle_irq_safe(adap->client_irq); + + return IRQ_HANDLED; +} + +static u32 cht_wc_i2c_adap_master_func(struct i2c_adapter *adap) +{ + /* This i2c adapter only supports SMBUS byte transfers */ + return I2C_FUNC_SMBUS_BYTE_DATA; +} + +static int cht_wc_i2c_adap_smbus_xfer(struct i2c_adapter *_adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + struct cht_wc_i2c_adap *adap = i2c_get_adapdata(_adap); + int ret; + + mutex_lock(&adap->adap_lock); + adap->io_error = false; + adap->done = false; + mutex_unlock(&adap->adap_lock); + + ret = regmap_write(adap->regmap, CHT_WC_I2C_CLIENT_ADDR, addr); + if (ret) + return ret; + + if (read_write == I2C_SMBUS_WRITE) { + ret = regmap_write(adap->regmap, CHT_WC_I2C_WRDATA, data->byte); + if (ret) + return ret; + } + + ret = regmap_write(adap->regmap, CHT_WC_I2C_REG_OFFSET, command); + if (ret) + return ret; + + ret = regmap_write(adap->regmap, CHT_WC_I2C_CTRL, + (read_write == I2C_SMBUS_WRITE) ? + CHT_WC_I2C_CTRL_WR : CHT_WC_I2C_CTRL_RD); + if (ret) + return ret; + + ret = wait_event_timeout(adap->wait, adap->done, msecs_to_jiffies(30)); + if (ret == 0) { + /* + * The CHT GPIO controller serializes all IRQs, sometimes + * causing significant delays, check status manually. + */ + cht_wc_i2c_adap_thread_handler(0, adap); + if (!adap->done) + return -ETIMEDOUT; + } + + ret = 0; + mutex_lock(&adap->adap_lock); + if (adap->io_error) + ret = -EIO; + else if (read_write == I2C_SMBUS_READ) + data->byte = adap->read_data; + mutex_unlock(&adap->adap_lock); + + return ret; +} + +static const struct i2c_algorithm cht_wc_i2c_adap_algo = { + .functionality = cht_wc_i2c_adap_master_func, + .smbus_xfer = cht_wc_i2c_adap_smbus_xfer, +}; + +/* + * We are an i2c-adapter which itself is part of an i2c-client. This means that + * transfers done through us take adapter->bus_lock twice, once for our parent + * i2c-adapter and once to take our own bus_lock. Lockdep does not like this + * nested locking, to make lockdep happy in the case of busses with muxes, the + * i2c-core's i2c_adapter_lock_bus function calls: + * rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter)); + * + * But i2c_adapter_depth only works when the direct parent of the adapter is + * another adapter, as it is only meant for muxes. In our case there is an + * i2c-client and MFD instantiated platform_device in the parent->child chain + * between the 2 devices. + * + * So we override the default i2c_lock_operations and pass a hardcoded + * depth of 1 to rt_mutex_lock_nested, to make lockdep happy. + * + * Note that if there were to be a mux attached to our adapter, this would + * break things again since the i2c-mux code expects the root-adapter to have + * a locking depth of 0. But we always have only 1 client directly attached + * in the form of the Charger IC paired with the CHT Whiskey Cove PMIC. + */ +static void cht_wc_i2c_adap_lock_bus(struct i2c_adapter *adapter, + unsigned int flags) +{ + rt_mutex_lock_nested(&adapter->bus_lock, 1); +} + +static int cht_wc_i2c_adap_trylock_bus(struct i2c_adapter *adapter, + unsigned int flags) +{ + return rt_mutex_trylock(&adapter->bus_lock); +} + +static void cht_wc_i2c_adap_unlock_bus(struct i2c_adapter *adapter, + unsigned int flags) +{ + rt_mutex_unlock(&adapter->bus_lock); +} + +static const struct i2c_lock_operations cht_wc_i2c_adap_lock_ops = { + .lock_bus = cht_wc_i2c_adap_lock_bus, + .trylock_bus = cht_wc_i2c_adap_trylock_bus, + .unlock_bus = cht_wc_i2c_adap_unlock_bus, +}; + +/**** irqchip for the client connected to the extchgr i2c adapter ****/ +static void cht_wc_i2c_irq_lock(struct irq_data *data) +{ + struct cht_wc_i2c_adap *adap = irq_data_get_irq_chip_data(data); + + mutex_lock(&adap->irqchip_lock); +} + +static void cht_wc_i2c_irq_sync_unlock(struct irq_data *data) +{ + struct cht_wc_i2c_adap *adap = irq_data_get_irq_chip_data(data); + int ret; + + if (adap->irq_mask != adap->old_irq_mask) { + ret = regmap_write(adap->regmap, CHT_WC_EXTCHGRIRQ_MSK, + adap->irq_mask); + if (ret == 0) + adap->old_irq_mask = adap->irq_mask; + else + dev_err(&adap->adapter.dev, "Error writing EXTCHGRIRQ_MSK\n"); + } + + mutex_unlock(&adap->irqchip_lock); +} + +static void cht_wc_i2c_irq_enable(struct irq_data *data) +{ + struct cht_wc_i2c_adap *adap = irq_data_get_irq_chip_data(data); + + adap->irq_mask &= ~CHT_WC_EXTCHGRIRQ_CLIENT_IRQ; +} + +static void cht_wc_i2c_irq_disable(struct irq_data *data) +{ + struct cht_wc_i2c_adap *adap = irq_data_get_irq_chip_data(data); + + adap->irq_mask |= CHT_WC_EXTCHGRIRQ_CLIENT_IRQ; +} + +static const struct irq_chip cht_wc_i2c_irq_chip = { + .irq_bus_lock = cht_wc_i2c_irq_lock, + .irq_bus_sync_unlock = cht_wc_i2c_irq_sync_unlock, + .irq_disable = cht_wc_i2c_irq_disable, + .irq_enable = cht_wc_i2c_irq_enable, + .name = "cht_wc_ext_chrg_irq_chip", +}; + +/********** GPD Win / Pocket charger IC settings **********/ +static const char * const bq24190_suppliers[] = { + "tcpm-source-psy-i2c-fusb302" }; + +static const struct property_entry bq24190_props[] = { + PROPERTY_ENTRY_STRING_ARRAY("supplied-from", bq24190_suppliers), + PROPERTY_ENTRY_BOOL("omit-battery-class"), + PROPERTY_ENTRY_BOOL("disable-reset"), + { } +}; + +static const struct software_node bq24190_node = { + .properties = bq24190_props, +}; + +static struct regulator_consumer_supply fusb302_consumer = { + .supply = "vbus", + /* Must match fusb302 dev_name in intel_cht_int33fe.c */ + .dev_name = "i2c-fusb302", +}; + +static const struct regulator_init_data bq24190_vbus_init_data = { + .constraints = { + /* The name is used in intel_cht_int33fe.c do not change. */ + .name = "cht_wc_usb_typec_vbus", + .valid_ops_mask = REGULATOR_CHANGE_STATUS, + }, + .consumer_supplies = &fusb302_consumer, + .num_consumer_supplies = 1, +}; + +static struct bq24190_platform_data bq24190_pdata = { + .regulator_init_data = &bq24190_vbus_init_data, +}; + +static struct i2c_board_info gpd_win_board_info = { + .type = "bq24190", + .addr = 0x6b, + .dev_name = "bq24190", + .swnode = &bq24190_node, + .platform_data = &bq24190_pdata, +}; + +/********** Xiaomi Mi Pad 2 charger IC settings **********/ +static struct regulator_consumer_supply bq2589x_vbus_consumer = { + .supply = "vbus", + .dev_name = "cht_wcove_pwrsrc", +}; + +static const struct regulator_init_data bq2589x_vbus_init_data = { + .constraints = { + .valid_ops_mask = REGULATOR_CHANGE_STATUS, + }, + .consumer_supplies = &bq2589x_vbus_consumer, + .num_consumer_supplies = 1, +}; + +static struct bq25890_platform_data bq2589x_pdata = { + .regulator_init_data = &bq2589x_vbus_init_data, +}; + +static const struct property_entry xiaomi_mipad2_props[] = { + PROPERTY_ENTRY_BOOL("linux,skip-reset"), + PROPERTY_ENTRY_BOOL("linux,read-back-settings"), + { } +}; + +static const struct software_node xiaomi_mipad2_node = { + .properties = xiaomi_mipad2_props, +}; + +static struct i2c_board_info xiaomi_mipad2_board_info = { + .type = "bq25890", + .addr = 0x6a, + .dev_name = "bq25890", + .swnode = &xiaomi_mipad2_node, + .platform_data = &bq2589x_pdata, +}; + +/********** Lenovo Yogabook YB1-X90F/-X91F/-X91L charger settings **********/ +static const char * const lenovo_yb1_bq25892_suppliers[] = { "cht_wcove_pwrsrc" }; + +static const struct property_entry lenovo_yb1_bq25892_props[] = { + PROPERTY_ENTRY_STRING_ARRAY("supplied-from", + lenovo_yb1_bq25892_suppliers), + PROPERTY_ENTRY_U32("linux,pump-express-vbus-max", 12000000), + PROPERTY_ENTRY_BOOL("linux,skip-reset"), + /* + * The firmware sets everything to the defaults, which leads to a + * somewhat low charge-current of 2048mA and worse to a battery-voltage + * of 4.2V instead of 4.35V (when booted without a charger connected). + * Use our own values instead of "linux,read-back-settings" to fix this. + */ + PROPERTY_ENTRY_U32("ti,charge-current", 4224000), + PROPERTY_ENTRY_U32("ti,battery-regulation-voltage", 4352000), + PROPERTY_ENTRY_U32("ti,termination-current", 256000), + PROPERTY_ENTRY_U32("ti,precharge-current", 128000), + PROPERTY_ENTRY_U32("ti,minimum-sys-voltage", 3500000), + PROPERTY_ENTRY_U32("ti,boost-voltage", 4998000), + PROPERTY_ENTRY_U32("ti,boost-max-current", 1400000), + PROPERTY_ENTRY_BOOL("ti,use-ilim-pin"), + { } +}; + +static const struct software_node lenovo_yb1_bq25892_node = { + .properties = lenovo_yb1_bq25892_props, +}; + +static struct i2c_board_info lenovo_yogabook1_board_info = { + .type = "bq25892", + .addr = 0x6b, + .dev_name = "bq25892", + .swnode = &lenovo_yb1_bq25892_node, + .platform_data = &bq2589x_pdata, +}; + +/********** Lenovo Yogabook YT3-X90F charger settings **********/ +static const char * const lenovo_yt3_bq25892_1_suppliers[] = { "cht_wcove_pwrsrc" }; + +/* + * bq25892 charger settings for the round li-ion cells in the hinge, + * this is the main / biggest battery. + */ +static const struct property_entry lenovo_yt3_bq25892_1_props[] = { + PROPERTY_ENTRY_STRING_ARRAY("supplied-from", lenovo_yt3_bq25892_1_suppliers), + PROPERTY_ENTRY_STRING("linux,secondary-charger-name", "bq25890-charger-0"), + PROPERTY_ENTRY_U32("linux,iinlim-percentage", 60), + PROPERTY_ENTRY_U32("linux,pump-express-vbus-max", 12000000), + PROPERTY_ENTRY_BOOL("linux,skip-reset"), + /* + * The firmware sets everything to the defaults, leading to a low(ish) + * charge-current and battery-voltage of 2048mA resp 4.2V. Use the + * Android values instead of "linux,read-back-settings" to fix this. + */ + PROPERTY_ENTRY_U32("ti,charge-current", 3072000), + PROPERTY_ENTRY_U32("ti,battery-regulation-voltage", 4352000), + PROPERTY_ENTRY_U32("ti,termination-current", 128000), + PROPERTY_ENTRY_U32("ti,precharge-current", 128000), + PROPERTY_ENTRY_U32("ti,minimum-sys-voltage", 3700000), + PROPERTY_ENTRY_BOOL("ti,use-ilim-pin"), + /* Set 5V boost current-limit to 1.2A (MAX/POR values are 2.45A/1.4A) */ + PROPERTY_ENTRY_U32("ti,boost-voltage", 4998000), + PROPERTY_ENTRY_U32("ti,boost-max-current", 1200000), + { } +}; + +static const struct software_node lenovo_yt3_bq25892_1_node = { + .properties = lenovo_yt3_bq25892_1_props, +}; + +/* bq25892 charger for the round li-ion cells in the hinge */ +static struct i2c_board_info lenovo_yoga_tab3_board_info = { + .type = "bq25892", + .addr = 0x6b, + .dev_name = "bq25892_1", + .swnode = &lenovo_yt3_bq25892_1_node, + .platform_data = &bq2589x_pdata, +}; + +static int cht_wc_i2c_adap_i2c_probe(struct platform_device *pdev) +{ + struct intel_soc_pmic *pmic = dev_get_drvdata(pdev->dev.parent); + struct i2c_board_info *board_info = NULL; + struct cht_wc_i2c_adap *adap; + int ret, reg, irq; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + adap = devm_kzalloc(&pdev->dev, sizeof(*adap), GFP_KERNEL); + if (!adap) + return -ENOMEM; + + init_waitqueue_head(&adap->wait); + mutex_init(&adap->adap_lock); + mutex_init(&adap->irqchip_lock); + adap->irqchip = cht_wc_i2c_irq_chip; + adap->regmap = pmic->regmap; + adap->adapter.owner = THIS_MODULE; + adap->adapter.class = I2C_CLASS_HWMON; + adap->adapter.algo = &cht_wc_i2c_adap_algo; + adap->adapter.lock_ops = &cht_wc_i2c_adap_lock_ops; + strscpy(adap->adapter.name, "PMIC I2C Adapter", + sizeof(adap->adapter.name)); + adap->adapter.dev.parent = &pdev->dev; + + /* Clear and activate i2c-adapter interrupts, disable client IRQ */ + adap->old_irq_mask = adap->irq_mask = ~CHT_WC_EXTCHGRIRQ_ADAP_IRQMASK; + + ret = regmap_read(adap->regmap, CHT_WC_I2C_RDDATA, ®); + if (ret) + return ret; + + ret = regmap_write(adap->regmap, CHT_WC_EXTCHGRIRQ, ~adap->irq_mask); + if (ret) + return ret; + + ret = regmap_write(adap->regmap, CHT_WC_EXTCHGRIRQ_MSK, adap->irq_mask); + if (ret) + return ret; + + /* Alloc and register client IRQ */ + adap->irq_domain = irq_domain_add_linear(NULL, 1, &irq_domain_simple_ops, NULL); + if (!adap->irq_domain) + return -ENOMEM; + + adap->client_irq = irq_create_mapping(adap->irq_domain, 0); + if (!adap->client_irq) { + ret = -ENOMEM; + goto remove_irq_domain; + } + + irq_set_chip_data(adap->client_irq, adap); + irq_set_chip_and_handler(adap->client_irq, &adap->irqchip, + handle_simple_irq); + + ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, + cht_wc_i2c_adap_thread_handler, + IRQF_ONESHOT, "PMIC I2C Adapter", adap); + if (ret) + goto remove_irq_domain; + + i2c_set_adapdata(&adap->adapter, adap); + ret = i2c_add_adapter(&adap->adapter); + if (ret) + goto remove_irq_domain; + + switch (pmic->cht_wc_model) { + case INTEL_CHT_WC_GPD_WIN_POCKET: + board_info = &gpd_win_board_info; + break; + case INTEL_CHT_WC_XIAOMI_MIPAD2: + board_info = &xiaomi_mipad2_board_info; + break; + case INTEL_CHT_WC_LENOVO_YOGABOOK1: + board_info = &lenovo_yogabook1_board_info; + break; + case INTEL_CHT_WC_LENOVO_YT3_X90: + board_info = &lenovo_yoga_tab3_board_info; + break; + default: + dev_warn(&pdev->dev, "Unknown model, not instantiating charger device\n"); + break; + } + + if (board_info) { + board_info->irq = adap->client_irq; + adap->client = i2c_new_client_device(&adap->adapter, board_info); + if (IS_ERR(adap->client)) { + ret = PTR_ERR(adap->client); + goto del_adapter; + } + } + + platform_set_drvdata(pdev, adap); + return 0; + +del_adapter: + i2c_del_adapter(&adap->adapter); +remove_irq_domain: + irq_domain_remove(adap->irq_domain); + return ret; +} + +static void cht_wc_i2c_adap_i2c_remove(struct platform_device *pdev) +{ + struct cht_wc_i2c_adap *adap = platform_get_drvdata(pdev); + + i2c_unregister_device(adap->client); + i2c_del_adapter(&adap->adapter); + irq_domain_remove(adap->irq_domain); +} + +static const struct platform_device_id cht_wc_i2c_adap_id_table[] = { + { .name = "cht_wcove_ext_chgr" }, + {}, +}; +MODULE_DEVICE_TABLE(platform, cht_wc_i2c_adap_id_table); + +static struct platform_driver cht_wc_i2c_adap_driver = { + .probe = cht_wc_i2c_adap_i2c_probe, + .remove_new = cht_wc_i2c_adap_i2c_remove, + .driver = { + .name = "cht_wcove_ext_chgr", + }, + .id_table = cht_wc_i2c_adap_id_table, +}; +module_platform_driver(cht_wc_i2c_adap_driver); + +MODULE_DESCRIPTION("Intel CHT Whiskey Cove PMIC I2C Master driver"); +MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-cp2615.c b/drivers/i2c/busses/i2c-cp2615.c new file mode 100644 index 000000000..3ded28632 --- /dev/null +++ b/drivers/i2c/busses/i2c-cp2615.c @@ -0,0 +1,336 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * i2c support for Silicon Labs' CP2615 Digital Audio Bridge + * + * (c) 2021, Bence Csókás <bence98@sch.bme.hu> + */ + +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/string.h> +#include <linux/usb.h> + +/** CP2615 I/O Protocol implementation */ + +#define CP2615_VID 0x10c4 +#define CP2615_PID 0xeac1 + +#define IOP_EP_IN 0x82 +#define IOP_EP_OUT 0x02 +#define IOP_IFN 1 +#define IOP_ALTSETTING 2 + +#define MAX_IOP_SIZE 64 +#define MAX_IOP_PAYLOAD_SIZE (MAX_IOP_SIZE - 6) +#define MAX_I2C_SIZE (MAX_IOP_PAYLOAD_SIZE - 4) + +enum cp2615_iop_msg_type { + iop_GetAccessoryInfo = 0xD100, + iop_AccessoryInfo = 0xA100, + iop_GetPortConfiguration = 0xD203, + iop_PortConfiguration = 0xA203, + iop_DoI2cTransfer = 0xD400, + iop_I2cTransferResult = 0xA400, + iop_GetSerialState = 0xD501, + iop_SerialState = 0xA501 +}; + +struct __packed cp2615_iop_msg { + __be16 preamble, length, msg; + u8 data[MAX_IOP_PAYLOAD_SIZE]; +}; + +#define PART_ID_A01 0x1400 +#define PART_ID_A02 0x1500 + +struct __packed cp2615_iop_accessory_info { + __be16 part_id, option_id, proto_ver; +}; + +struct __packed cp2615_i2c_transfer { + u8 tag, i2caddr, read_len, write_len; + u8 data[MAX_I2C_SIZE]; +}; + +/* Possible values for struct cp2615_i2c_transfer_result.status */ +enum cp2615_i2c_status { + /* Writing to the internal EEPROM failed, because it is locked */ + CP2615_CFG_LOCKED = -6, + /* read_len or write_len out of range */ + CP2615_INVALID_PARAM = -4, + /* I2C slave did not ACK in time */ + CP2615_TIMEOUT, + /* I2C bus busy */ + CP2615_BUS_BUSY, + /* I2C bus error (ie. device NAK'd the request) */ + CP2615_BUS_ERROR, + CP2615_SUCCESS +}; + +struct __packed cp2615_i2c_transfer_result { + u8 tag, i2caddr; + s8 status; + u8 read_len; + u8 data[MAX_I2C_SIZE]; +}; + +static int cp2615_init_iop_msg(struct cp2615_iop_msg *ret, enum cp2615_iop_msg_type msg, + const void *data, size_t data_len) +{ + if (data_len > MAX_IOP_PAYLOAD_SIZE) + return -EFBIG; + + if (!ret) + return -EINVAL; + + ret->preamble = 0x2A2A; + ret->length = htons(data_len + 6); + ret->msg = htons(msg); + if (data && data_len) + memcpy(&ret->data, data, data_len); + return 0; +} + +static int cp2615_init_i2c_msg(struct cp2615_iop_msg *ret, const struct cp2615_i2c_transfer *data) +{ + return cp2615_init_iop_msg(ret, iop_DoI2cTransfer, data, 4 + data->write_len); +} + +/* Translates status codes to Linux errno's */ +static int cp2615_check_status(enum cp2615_i2c_status status) +{ + switch (status) { + case CP2615_SUCCESS: + return 0; + case CP2615_BUS_ERROR: + return -ENXIO; + case CP2615_BUS_BUSY: + return -EAGAIN; + case CP2615_TIMEOUT: + return -ETIMEDOUT; + case CP2615_INVALID_PARAM: + return -EINVAL; + case CP2615_CFG_LOCKED: + return -EPERM; + } + /* Unknown error code */ + return -EPROTO; +} + +/** Driver code */ + +static int +cp2615_i2c_send(struct usb_interface *usbif, struct cp2615_i2c_transfer *i2c_w) +{ + struct cp2615_iop_msg *msg = kzalloc(sizeof(*msg), GFP_KERNEL); + struct usb_device *usbdev = interface_to_usbdev(usbif); + int res = cp2615_init_i2c_msg(msg, i2c_w); + + if (!res) + res = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, IOP_EP_OUT), + msg, ntohs(msg->length), NULL, 0); + kfree(msg); + return res; +} + +static int +cp2615_i2c_recv(struct usb_interface *usbif, unsigned char tag, void *buf) +{ + struct usb_device *usbdev = interface_to_usbdev(usbif); + struct cp2615_iop_msg *msg; + struct cp2615_i2c_transfer_result *i2c_r; + int res; + + msg = kzalloc(sizeof(*msg), GFP_KERNEL); + if (!msg) + return -ENOMEM; + + res = usb_bulk_msg(usbdev, usb_rcvbulkpipe(usbdev, IOP_EP_IN), msg, + sizeof(struct cp2615_iop_msg), NULL, 0); + if (res < 0) { + kfree(msg); + return res; + } + + i2c_r = (struct cp2615_i2c_transfer_result *)&msg->data; + if (msg->msg != htons(iop_I2cTransferResult) || i2c_r->tag != tag) { + kfree(msg); + return -EIO; + } + + res = cp2615_check_status(i2c_r->status); + if (!res) + memcpy(buf, &i2c_r->data, i2c_r->read_len); + + kfree(msg); + return res; +} + +/* Checks if the IOP is functional by querying the part's ID */ +static int cp2615_check_iop(struct usb_interface *usbif) +{ + struct cp2615_iop_msg *msg = kzalloc(sizeof(*msg), GFP_KERNEL); + struct cp2615_iop_accessory_info *info = (struct cp2615_iop_accessory_info *)&msg->data; + struct usb_device *usbdev = interface_to_usbdev(usbif); + int res = cp2615_init_iop_msg(msg, iop_GetAccessoryInfo, NULL, 0); + + if (res) + goto out; + + res = usb_bulk_msg(usbdev, usb_sndbulkpipe(usbdev, IOP_EP_OUT), + msg, ntohs(msg->length), NULL, 0); + if (res) + goto out; + + res = usb_bulk_msg(usbdev, usb_rcvbulkpipe(usbdev, IOP_EP_IN), + msg, sizeof(struct cp2615_iop_msg), NULL, 0); + if (res) + goto out; + + if (msg->msg != htons(iop_AccessoryInfo)) { + res = -EIO; + goto out; + } + + switch (ntohs(info->part_id)) { + case PART_ID_A01: + dev_dbg(&usbif->dev, "Found A01 part. (WARNING: errata exists!)\n"); + break; + case PART_ID_A02: + dev_dbg(&usbif->dev, "Found good A02 part.\n"); + break; + default: + dev_warn(&usbif->dev, "Unknown part ID %04X\n", ntohs(info->part_id)); + } + +out: + kfree(msg); + return res; +} + +static int +cp2615_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + struct usb_interface *usbif = adap->algo_data; + int i = 0, ret = 0; + struct i2c_msg *msg; + struct cp2615_i2c_transfer i2c_w = {0}; + + dev_dbg(&usbif->dev, "Doing %d I2C transactions\n", num); + + for (; !ret && i < num; i++) { + msg = &msgs[i]; + + i2c_w.tag = 0xdd; + i2c_w.i2caddr = i2c_8bit_addr_from_msg(msg); + if (msg->flags & I2C_M_RD) { + i2c_w.read_len = msg->len; + i2c_w.write_len = 0; + } else { + i2c_w.read_len = 0; + i2c_w.write_len = msg->len; + memcpy(&i2c_w.data, msg->buf, i2c_w.write_len); + } + ret = cp2615_i2c_send(usbif, &i2c_w); + if (ret) + break; + ret = cp2615_i2c_recv(usbif, i2c_w.tag, msg->buf); + } + if (ret < 0) + return ret; + return i; +} + +static u32 +cp2615_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm cp2615_i2c_algo = { + .master_xfer = cp2615_i2c_master_xfer, + .functionality = cp2615_i2c_func, +}; + +/* + * This chip has some limitations: one is that the USB endpoint + * can only receive 64 bytes/transfer, that leaves 54 bytes for + * the I2C transfer. On top of that, EITHER read_len OR write_len + * may be zero, but not both. If both are non-zero, the adapter + * issues a write followed by a read. And the chip does not + * support repeated START between the write and read phases. + */ +static struct i2c_adapter_quirks cp2615_i2c_quirks = { + .max_write_len = MAX_I2C_SIZE, + .max_read_len = MAX_I2C_SIZE, + .flags = I2C_AQ_COMB_WRITE_THEN_READ | I2C_AQ_NO_ZERO_LEN | I2C_AQ_NO_REP_START, + .max_comb_1st_msg_len = MAX_I2C_SIZE, + .max_comb_2nd_msg_len = MAX_I2C_SIZE +}; + +static void +cp2615_i2c_remove(struct usb_interface *usbif) +{ + struct i2c_adapter *adap = usb_get_intfdata(usbif); + + usb_set_intfdata(usbif, NULL); + i2c_del_adapter(adap); +} + +static int +cp2615_i2c_probe(struct usb_interface *usbif, const struct usb_device_id *id) +{ + int ret = 0; + struct i2c_adapter *adap; + struct usb_device *usbdev = interface_to_usbdev(usbif); + + ret = usb_set_interface(usbdev, IOP_IFN, IOP_ALTSETTING); + if (ret) + return ret; + + ret = cp2615_check_iop(usbif); + if (ret) + return ret; + + adap = devm_kzalloc(&usbif->dev, sizeof(struct i2c_adapter), GFP_KERNEL); + if (!adap) + return -ENOMEM; + + strncpy(adap->name, usbdev->serial, sizeof(adap->name) - 1); + adap->owner = THIS_MODULE; + adap->dev.parent = &usbif->dev; + adap->dev.of_node = usbif->dev.of_node; + adap->timeout = HZ; + adap->algo = &cp2615_i2c_algo; + adap->quirks = &cp2615_i2c_quirks; + adap->algo_data = usbif; + + ret = i2c_add_adapter(adap); + if (ret) + return ret; + + usb_set_intfdata(usbif, adap); + return 0; +} + +static const struct usb_device_id id_table[] = { + { USB_DEVICE_INTERFACE_NUMBER(CP2615_VID, CP2615_PID, IOP_IFN) }, + { } +}; + +MODULE_DEVICE_TABLE(usb, id_table); + +static struct usb_driver cp2615_i2c_driver = { + .name = "i2c-cp2615", + .probe = cp2615_i2c_probe, + .disconnect = cp2615_i2c_remove, + .id_table = id_table, +}; + +module_usb_driver(cp2615_i2c_driver); + +MODULE_AUTHOR("Bence Csókás <bence98@sch.bme.hu>"); +MODULE_DESCRIPTION("CP2615 I2C bus driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-cpm.c b/drivers/i2c/busses/i2c-cpm.c new file mode 100644 index 000000000..9a664abf7 --- /dev/null +++ b/drivers/i2c/busses/i2c-cpm.c @@ -0,0 +1,715 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Freescale CPM1/CPM2 I2C interface. + * Copyright (c) 1999 Dan Malek (dmalek@jlc.net). + * + * moved into proper i2c interface; + * Brad Parker (brad@heeltoe.com) + * + * Parts from dbox2_i2c.c (cvs.tuxbox.org) + * (C) 2000-2001 Felix Domke (tmbinc@gmx.net), Gillem (htoa@gmx.net) + * + * (C) 2007 Montavista Software, Inc. + * Vitaly Bordug <vitb@kernel.crashing.org> + * + * Converted to of_platform_device. Renamed to i2c-cpm.c. + * (C) 2007,2008 Jochen Friedrich <jochen@scram.de> + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/errno.h> +#include <linux/stddef.h> +#include <linux/i2c.h> +#include <linux/io.h> +#include <linux/dma-mapping.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> +#include <sysdev/fsl_soc.h> +#include <asm/cpm.h> + +/* Try to define this if you have an older CPU (earlier than rev D4) */ +/* However, better use a GPIO based bitbang driver in this case :/ */ +#undef I2C_CHIP_ERRATA + +#define CPM_MAX_READ 513 +#define CPM_MAXBD 4 + +#define I2C_EB (0x10) /* Big endian mode */ +#define I2C_EB_CPM2 (0x30) /* Big endian mode, memory snoop */ + +#define DPRAM_BASE ((u8 __iomem __force *)cpm_muram_addr(0)) + +/* I2C parameter RAM. */ +struct i2c_ram { + ushort rbase; /* Rx Buffer descriptor base address */ + ushort tbase; /* Tx Buffer descriptor base address */ + u_char rfcr; /* Rx function code */ + u_char tfcr; /* Tx function code */ + ushort mrblr; /* Max receive buffer length */ + uint rstate; /* Internal */ + uint rdp; /* Internal */ + ushort rbptr; /* Rx Buffer descriptor pointer */ + ushort rbc; /* Internal */ + uint rxtmp; /* Internal */ + uint tstate; /* Internal */ + uint tdp; /* Internal */ + ushort tbptr; /* Tx Buffer descriptor pointer */ + ushort tbc; /* Internal */ + uint txtmp; /* Internal */ + char res1[4]; /* Reserved */ + ushort rpbase; /* Relocation pointer */ + char res2[2]; /* Reserved */ + /* The following elements are only for CPM2 */ + char res3[4]; /* Reserved */ + uint sdmatmp; /* Internal */ +}; + +#define I2COM_START 0x80 +#define I2COM_MASTER 0x01 +#define I2CER_TXE 0x10 +#define I2CER_BUSY 0x04 +#define I2CER_TXB 0x02 +#define I2CER_RXB 0x01 +#define I2MOD_EN 0x01 + +/* I2C Registers */ +struct i2c_reg { + u8 i2mod; + u8 res1[3]; + u8 i2add; + u8 res2[3]; + u8 i2brg; + u8 res3[3]; + u8 i2com; + u8 res4[3]; + u8 i2cer; + u8 res5[3]; + u8 i2cmr; +}; + +struct cpm_i2c { + char *base; + struct platform_device *ofdev; + struct i2c_adapter adap; + uint dp_addr; + int version; /* CPM1=1, CPM2=2 */ + int irq; + int cp_command; + int freq; + struct i2c_reg __iomem *i2c_reg; + struct i2c_ram __iomem *i2c_ram; + u16 i2c_addr; + wait_queue_head_t i2c_wait; + cbd_t __iomem *tbase; + cbd_t __iomem *rbase; + u_char *txbuf[CPM_MAXBD]; + u_char *rxbuf[CPM_MAXBD]; + dma_addr_t txdma[CPM_MAXBD]; + dma_addr_t rxdma[CPM_MAXBD]; +}; + +static irqreturn_t cpm_i2c_interrupt(int irq, void *dev_id) +{ + struct cpm_i2c *cpm; + struct i2c_reg __iomem *i2c_reg; + struct i2c_adapter *adap = dev_id; + int i; + + cpm = i2c_get_adapdata(dev_id); + i2c_reg = cpm->i2c_reg; + + /* Clear interrupt. */ + i = in_8(&i2c_reg->i2cer); + out_8(&i2c_reg->i2cer, i); + + dev_dbg(&adap->dev, "Interrupt: %x\n", i); + + wake_up(&cpm->i2c_wait); + + return i ? IRQ_HANDLED : IRQ_NONE; +} + +static void cpm_reset_i2c_params(struct cpm_i2c *cpm) +{ + struct i2c_ram __iomem *i2c_ram = cpm->i2c_ram; + + /* Set up the I2C parameters in the parameter ram. */ + out_be16(&i2c_ram->tbase, (u8 __iomem *)cpm->tbase - DPRAM_BASE); + out_be16(&i2c_ram->rbase, (u8 __iomem *)cpm->rbase - DPRAM_BASE); + + if (cpm->version == 1) { + out_8(&i2c_ram->tfcr, I2C_EB); + out_8(&i2c_ram->rfcr, I2C_EB); + } else { + out_8(&i2c_ram->tfcr, I2C_EB_CPM2); + out_8(&i2c_ram->rfcr, I2C_EB_CPM2); + } + + out_be16(&i2c_ram->mrblr, CPM_MAX_READ); + + out_be32(&i2c_ram->rstate, 0); + out_be32(&i2c_ram->rdp, 0); + out_be16(&i2c_ram->rbptr, 0); + out_be16(&i2c_ram->rbc, 0); + out_be32(&i2c_ram->rxtmp, 0); + out_be32(&i2c_ram->tstate, 0); + out_be32(&i2c_ram->tdp, 0); + out_be16(&i2c_ram->tbptr, 0); + out_be16(&i2c_ram->tbc, 0); + out_be32(&i2c_ram->txtmp, 0); +} + +static void cpm_i2c_force_close(struct i2c_adapter *adap) +{ + struct cpm_i2c *cpm = i2c_get_adapdata(adap); + struct i2c_reg __iomem *i2c_reg = cpm->i2c_reg; + + dev_dbg(&adap->dev, "cpm_i2c_force_close()\n"); + + cpm_command(cpm->cp_command, CPM_CR_CLOSE_RX_BD); + + out_8(&i2c_reg->i2cmr, 0x00); /* Disable all interrupts */ + out_8(&i2c_reg->i2cer, 0xff); +} + +static void cpm_i2c_parse_message(struct i2c_adapter *adap, + struct i2c_msg *pmsg, int num, int tx, int rx) +{ + cbd_t __iomem *tbdf; + cbd_t __iomem *rbdf; + u_char addr; + u_char *tb; + u_char *rb; + struct cpm_i2c *cpm = i2c_get_adapdata(adap); + + tbdf = cpm->tbase + tx; + rbdf = cpm->rbase + rx; + + addr = i2c_8bit_addr_from_msg(pmsg); + + tb = cpm->txbuf[tx]; + rb = cpm->rxbuf[rx]; + + /* Align read buffer */ + rb = (u_char *) (((ulong) rb + 1) & ~1); + + tb[0] = addr; /* Device address byte w/rw flag */ + + out_be16(&tbdf->cbd_datlen, pmsg->len + 1); + out_be16(&tbdf->cbd_sc, 0); + + if (!(pmsg->flags & I2C_M_NOSTART)) + setbits16(&tbdf->cbd_sc, BD_I2C_START); + + if (tx + 1 == num) + setbits16(&tbdf->cbd_sc, BD_SC_LAST | BD_SC_WRAP); + + if (pmsg->flags & I2C_M_RD) { + /* + * To read, we need an empty buffer of the proper length. + * All that is used is the first byte for address, the remainder + * is just used for timing (and doesn't really have to exist). + */ + + dev_dbg(&adap->dev, "cpm_i2c_read(abyte=0x%x)\n", addr); + + out_be16(&rbdf->cbd_datlen, 0); + out_be16(&rbdf->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT); + + if (rx + 1 == CPM_MAXBD) + setbits16(&rbdf->cbd_sc, BD_SC_WRAP); + + eieio(); + setbits16(&tbdf->cbd_sc, BD_SC_READY); + } else { + dev_dbg(&adap->dev, "cpm_i2c_write(abyte=0x%x)\n", addr); + + memcpy(tb+1, pmsg->buf, pmsg->len); + + eieio(); + setbits16(&tbdf->cbd_sc, BD_SC_READY | BD_SC_INTRPT); + } +} + +static int cpm_i2c_check_message(struct i2c_adapter *adap, + struct i2c_msg *pmsg, int tx, int rx) +{ + cbd_t __iomem *tbdf; + cbd_t __iomem *rbdf; + u_char *tb; + u_char *rb; + struct cpm_i2c *cpm = i2c_get_adapdata(adap); + + tbdf = cpm->tbase + tx; + rbdf = cpm->rbase + rx; + + tb = cpm->txbuf[tx]; + rb = cpm->rxbuf[rx]; + + /* Align read buffer */ + rb = (u_char *) (((uint) rb + 1) & ~1); + + eieio(); + if (pmsg->flags & I2C_M_RD) { + dev_dbg(&adap->dev, "tx sc 0x%04x, rx sc 0x%04x\n", + in_be16(&tbdf->cbd_sc), in_be16(&rbdf->cbd_sc)); + + if (in_be16(&tbdf->cbd_sc) & BD_SC_NAK) { + dev_dbg(&adap->dev, "I2C read; No ack\n"); + return -ENXIO; + } + if (in_be16(&rbdf->cbd_sc) & BD_SC_EMPTY) { + dev_err(&adap->dev, + "I2C read; complete but rbuf empty\n"); + return -EREMOTEIO; + } + if (in_be16(&rbdf->cbd_sc) & BD_SC_OV) { + dev_err(&adap->dev, "I2C read; Overrun\n"); + return -EREMOTEIO; + } + memcpy(pmsg->buf, rb, pmsg->len); + } else { + dev_dbg(&adap->dev, "tx sc %d 0x%04x\n", tx, + in_be16(&tbdf->cbd_sc)); + + if (in_be16(&tbdf->cbd_sc) & BD_SC_NAK) { + dev_dbg(&adap->dev, "I2C write; No ack\n"); + return -ENXIO; + } + if (in_be16(&tbdf->cbd_sc) & BD_SC_UN) { + dev_err(&adap->dev, "I2C write; Underrun\n"); + return -EIO; + } + if (in_be16(&tbdf->cbd_sc) & BD_SC_CL) { + dev_err(&adap->dev, "I2C write; Collision\n"); + return -EIO; + } + } + return 0; +} + +static int cpm_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + struct cpm_i2c *cpm = i2c_get_adapdata(adap); + struct i2c_reg __iomem *i2c_reg = cpm->i2c_reg; + struct i2c_ram __iomem *i2c_ram = cpm->i2c_ram; + struct i2c_msg *pmsg; + int ret; + int tptr; + int rptr; + cbd_t __iomem *tbdf; + cbd_t __iomem *rbdf; + + /* Reset to use first buffer */ + out_be16(&i2c_ram->rbptr, in_be16(&i2c_ram->rbase)); + out_be16(&i2c_ram->tbptr, in_be16(&i2c_ram->tbase)); + + tbdf = cpm->tbase; + rbdf = cpm->rbase; + + tptr = 0; + rptr = 0; + + /* + * If there was a collision in the last i2c transaction, + * Set I2COM_MASTER as it was cleared during collision. + */ + if (in_be16(&tbdf->cbd_sc) & BD_SC_CL) { + out_8(&cpm->i2c_reg->i2com, I2COM_MASTER); + } + + while (tptr < num) { + pmsg = &msgs[tptr]; + dev_dbg(&adap->dev, "R: %d T: %d\n", rptr, tptr); + + cpm_i2c_parse_message(adap, pmsg, num, tptr, rptr); + if (pmsg->flags & I2C_M_RD) + rptr++; + tptr++; + } + /* Start transfer now */ + /* Enable RX/TX/Error interupts */ + out_8(&i2c_reg->i2cmr, I2CER_TXE | I2CER_TXB | I2CER_RXB); + out_8(&i2c_reg->i2cer, 0xff); /* Clear interrupt status */ + /* Chip bug, set enable here */ + setbits8(&i2c_reg->i2mod, I2MOD_EN); /* Enable */ + /* Begin transmission */ + setbits8(&i2c_reg->i2com, I2COM_START); + + tptr = 0; + rptr = 0; + + while (tptr < num) { + /* Check for outstanding messages */ + dev_dbg(&adap->dev, "test ready.\n"); + pmsg = &msgs[tptr]; + if (pmsg->flags & I2C_M_RD) + ret = wait_event_timeout(cpm->i2c_wait, + (in_be16(&tbdf[tptr].cbd_sc) & BD_SC_NAK) || + !(in_be16(&rbdf[rptr].cbd_sc) & BD_SC_EMPTY), + 1 * HZ); + else + ret = wait_event_timeout(cpm->i2c_wait, + !(in_be16(&tbdf[tptr].cbd_sc) & BD_SC_READY), + 1 * HZ); + if (ret == 0) { + ret = -EREMOTEIO; + dev_err(&adap->dev, "I2C transfer: timeout\n"); + goto out_err; + } + if (ret > 0) { + dev_dbg(&adap->dev, "ready.\n"); + ret = cpm_i2c_check_message(adap, pmsg, tptr, rptr); + tptr++; + if (pmsg->flags & I2C_M_RD) + rptr++; + if (ret) + goto out_err; + } + } +#ifdef I2C_CHIP_ERRATA + /* + * Chip errata, clear enable. This is not needed on rev D4 CPUs. + * Disabling I2C too early may cause too short stop condition + */ + udelay(4); + clrbits8(&i2c_reg->i2mod, I2MOD_EN); +#endif + return (num); + +out_err: + cpm_i2c_force_close(adap); +#ifdef I2C_CHIP_ERRATA + /* + * Chip errata, clear enable. This is not needed on rev D4 CPUs. + */ + clrbits8(&i2c_reg->i2mod, I2MOD_EN); +#endif + return ret; +} + +static u32 cpm_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); +} + +/* -----exported algorithm data: ------------------------------------- */ + +static const struct i2c_algorithm cpm_i2c_algo = { + .master_xfer = cpm_i2c_xfer, + .functionality = cpm_i2c_func, +}; + +/* CPM_MAX_READ is also limiting writes according to the code! */ +static const struct i2c_adapter_quirks cpm_i2c_quirks = { + .max_num_msgs = CPM_MAXBD, + .max_read_len = CPM_MAX_READ, + .max_write_len = CPM_MAX_READ, +}; + +static const struct i2c_adapter cpm_ops = { + .owner = THIS_MODULE, + .name = "i2c-cpm", + .algo = &cpm_i2c_algo, + .quirks = &cpm_i2c_quirks, +}; + +static int cpm_i2c_setup(struct cpm_i2c *cpm) +{ + struct platform_device *ofdev = cpm->ofdev; + const u32 *data; + int len, ret, i; + void __iomem *i2c_base; + cbd_t __iomem *tbdf; + cbd_t __iomem *rbdf; + unsigned char brg; + + dev_dbg(&cpm->ofdev->dev, "cpm_i2c_setup()\n"); + + init_waitqueue_head(&cpm->i2c_wait); + + cpm->irq = irq_of_parse_and_map(ofdev->dev.of_node, 0); + if (!cpm->irq) + return -EINVAL; + + /* Install interrupt handler. */ + ret = request_irq(cpm->irq, cpm_i2c_interrupt, 0, "cpm_i2c", + &cpm->adap); + if (ret) + return ret; + + /* I2C parameter RAM */ + i2c_base = of_iomap(ofdev->dev.of_node, 1); + if (i2c_base == NULL) { + ret = -EINVAL; + goto out_irq; + } + + if (of_device_is_compatible(ofdev->dev.of_node, "fsl,cpm1-i2c")) { + + /* Check for and use a microcode relocation patch. */ + cpm->i2c_ram = i2c_base; + cpm->i2c_addr = in_be16(&cpm->i2c_ram->rpbase); + + /* + * Maybe should use cpm_muram_alloc instead of hardcoding + * this in micropatch.c + */ + if (cpm->i2c_addr) { + cpm->i2c_ram = cpm_muram_addr(cpm->i2c_addr); + iounmap(i2c_base); + } + + cpm->version = 1; + + } else if (of_device_is_compatible(ofdev->dev.of_node, "fsl,cpm2-i2c")) { + cpm->i2c_addr = cpm_muram_alloc(sizeof(struct i2c_ram), 64); + cpm->i2c_ram = cpm_muram_addr(cpm->i2c_addr); + out_be16(i2c_base, cpm->i2c_addr); + iounmap(i2c_base); + + cpm->version = 2; + + } else { + iounmap(i2c_base); + ret = -EINVAL; + goto out_irq; + } + + /* I2C control/status registers */ + cpm->i2c_reg = of_iomap(ofdev->dev.of_node, 0); + if (cpm->i2c_reg == NULL) { + ret = -EINVAL; + goto out_ram; + } + + data = of_get_property(ofdev->dev.of_node, "fsl,cpm-command", &len); + if (!data || len != 4) { + ret = -EINVAL; + goto out_reg; + } + cpm->cp_command = *data; + + data = of_get_property(ofdev->dev.of_node, "linux,i2c-class", &len); + if (data && len == 4) + cpm->adap.class = *data; + + data = of_get_property(ofdev->dev.of_node, "clock-frequency", &len); + if (data && len == 4) + cpm->freq = *data; + else + cpm->freq = 60000; /* use 60kHz i2c clock by default */ + + /* + * Allocate space for CPM_MAXBD transmit and receive buffer + * descriptors in the DP ram. + */ + cpm->dp_addr = cpm_muram_alloc(sizeof(cbd_t) * 2 * CPM_MAXBD, 8); + if (!cpm->dp_addr) { + ret = -ENOMEM; + goto out_reg; + } + + cpm->tbase = cpm_muram_addr(cpm->dp_addr); + cpm->rbase = cpm_muram_addr(cpm->dp_addr + sizeof(cbd_t) * CPM_MAXBD); + + /* Allocate TX and RX buffers */ + + tbdf = cpm->tbase; + rbdf = cpm->rbase; + + for (i = 0; i < CPM_MAXBD; i++) { + cpm->rxbuf[i] = dma_alloc_coherent(&cpm->ofdev->dev, + CPM_MAX_READ + 1, + &cpm->rxdma[i], GFP_KERNEL); + if (!cpm->rxbuf[i]) { + ret = -ENOMEM; + goto out_muram; + } + out_be32(&rbdf[i].cbd_bufaddr, ((cpm->rxdma[i] + 1) & ~1)); + + cpm->txbuf[i] = dma_alloc_coherent(&cpm->ofdev->dev, + CPM_MAX_READ + 1, + &cpm->txdma[i], GFP_KERNEL); + if (!cpm->txbuf[i]) { + ret = -ENOMEM; + goto out_muram; + } + out_be32(&tbdf[i].cbd_bufaddr, cpm->txdma[i]); + } + + /* Initialize Tx/Rx parameters. */ + + cpm_reset_i2c_params(cpm); + + dev_dbg(&cpm->ofdev->dev, "i2c_ram 0x%p, i2c_addr 0x%04x, freq %d\n", + cpm->i2c_ram, cpm->i2c_addr, cpm->freq); + dev_dbg(&cpm->ofdev->dev, "tbase 0x%04x, rbase 0x%04x\n", + (u8 __iomem *)cpm->tbase - DPRAM_BASE, + (u8 __iomem *)cpm->rbase - DPRAM_BASE); + + cpm_command(cpm->cp_command, CPM_CR_INIT_TRX); + + /* + * Select an invalid address. Just make sure we don't use loopback mode + */ + out_8(&cpm->i2c_reg->i2add, 0x7f << 1); + + /* + * PDIV is set to 00 in i2mod, so brgclk/32 is used as input to the + * i2c baud rate generator. This is divided by 2 x (DIV + 3) to get + * the actual i2c bus frequency. + */ + brg = get_brgfreq() / (32 * 2 * cpm->freq) - 3; + out_8(&cpm->i2c_reg->i2brg, brg); + + out_8(&cpm->i2c_reg->i2mod, 0x00); + out_8(&cpm->i2c_reg->i2com, I2COM_MASTER); /* Master mode */ + + /* Disable interrupts. */ + out_8(&cpm->i2c_reg->i2cmr, 0); + out_8(&cpm->i2c_reg->i2cer, 0xff); + + return 0; + +out_muram: + for (i = 0; i < CPM_MAXBD; i++) { + if (cpm->rxbuf[i]) + dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1, + cpm->rxbuf[i], cpm->rxdma[i]); + if (cpm->txbuf[i]) + dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1, + cpm->txbuf[i], cpm->txdma[i]); + } + cpm_muram_free(cpm->dp_addr); +out_reg: + iounmap(cpm->i2c_reg); +out_ram: + if ((cpm->version == 1) && (!cpm->i2c_addr)) + iounmap(cpm->i2c_ram); + if (cpm->version == 2) + cpm_muram_free(cpm->i2c_addr); +out_irq: + free_irq(cpm->irq, &cpm->adap); + return ret; +} + +static void cpm_i2c_shutdown(struct cpm_i2c *cpm) +{ + int i; + + /* Shut down I2C. */ + clrbits8(&cpm->i2c_reg->i2mod, I2MOD_EN); + + /* Disable interrupts */ + out_8(&cpm->i2c_reg->i2cmr, 0); + out_8(&cpm->i2c_reg->i2cer, 0xff); + + free_irq(cpm->irq, &cpm->adap); + + /* Free all memory */ + for (i = 0; i < CPM_MAXBD; i++) { + dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1, + cpm->rxbuf[i], cpm->rxdma[i]); + dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1, + cpm->txbuf[i], cpm->txdma[i]); + } + + cpm_muram_free(cpm->dp_addr); + iounmap(cpm->i2c_reg); + + if ((cpm->version == 1) && (!cpm->i2c_addr)) + iounmap(cpm->i2c_ram); + if (cpm->version == 2) + cpm_muram_free(cpm->i2c_addr); +} + +static int cpm_i2c_probe(struct platform_device *ofdev) +{ + int result, len; + struct cpm_i2c *cpm; + const u32 *data; + + cpm = kzalloc(sizeof(struct cpm_i2c), GFP_KERNEL); + if (!cpm) + return -ENOMEM; + + cpm->ofdev = ofdev; + + platform_set_drvdata(ofdev, cpm); + + cpm->adap = cpm_ops; + i2c_set_adapdata(&cpm->adap, cpm); + cpm->adap.dev.parent = &ofdev->dev; + cpm->adap.dev.of_node = of_node_get(ofdev->dev.of_node); + + result = cpm_i2c_setup(cpm); + if (result) { + dev_err(&ofdev->dev, "Unable to init hardware\n"); + goto out_free; + } + + /* register new adapter to i2c module... */ + + data = of_get_property(ofdev->dev.of_node, "linux,i2c-index", &len); + cpm->adap.nr = (data && len == 4) ? be32_to_cpup(data) : -1; + result = i2c_add_numbered_adapter(&cpm->adap); + + if (result < 0) + goto out_shut; + + dev_dbg(&ofdev->dev, "hw routines for %s registered.\n", + cpm->adap.name); + + return 0; +out_shut: + cpm_i2c_shutdown(cpm); +out_free: + kfree(cpm); + + return result; +} + +static void cpm_i2c_remove(struct platform_device *ofdev) +{ + struct cpm_i2c *cpm = platform_get_drvdata(ofdev); + + i2c_del_adapter(&cpm->adap); + + cpm_i2c_shutdown(cpm); + + kfree(cpm); +} + +static const struct of_device_id cpm_i2c_match[] = { + { + .compatible = "fsl,cpm1-i2c", + }, + { + .compatible = "fsl,cpm2-i2c", + }, + {}, +}; + +MODULE_DEVICE_TABLE(of, cpm_i2c_match); + +static struct platform_driver cpm_i2c_driver = { + .probe = cpm_i2c_probe, + .remove_new = cpm_i2c_remove, + .driver = { + .name = "fsl-i2c-cpm", + .of_match_table = cpm_i2c_match, + }, +}; + +module_platform_driver(cpm_i2c_driver); + +MODULE_AUTHOR("Jochen Friedrich <jochen@scram.de>"); +MODULE_DESCRIPTION("I2C-Bus adapter routines for CPM boards"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-cros-ec-tunnel.c b/drivers/i2c/busses/i2c-cros-ec-tunnel.c new file mode 100644 index 000000000..2737fd8ab --- /dev/null +++ b/drivers/i2c/busses/i2c-cros-ec-tunnel.c @@ -0,0 +1,319 @@ +// SPDX-License-Identifier: GPL-2.0+ +// Expose an I2C passthrough to the ChromeOS EC. +// +// Copyright (C) 2013 Google, Inc. + +#include <linux/acpi.h> +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/platform_data/cros_ec_commands.h> +#include <linux/platform_data/cros_ec_proto.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#define I2C_MAX_RETRIES 3 + +/** + * struct ec_i2c_device - Driver data for I2C tunnel + * + * @dev: Device node + * @adap: I2C adapter + * @ec: Pointer to EC device + * @remote_bus: The EC bus number we tunnel to on the other side. + * @request_buf: Buffer for transmitting data; we expect most transfers to fit. + * @response_buf: Buffer for receiving data; we expect most transfers to fit. + */ + +struct ec_i2c_device { + struct device *dev; + struct i2c_adapter adap; + struct cros_ec_device *ec; + + u16 remote_bus; + + u8 request_buf[256]; + u8 response_buf[256]; +}; + +/** + * ec_i2c_count_message - Count bytes needed for ec_i2c_construct_message + * + * @i2c_msgs: The i2c messages to read + * @num: The number of i2c messages. + * + * Returns the number of bytes the messages will take up. + */ +static int ec_i2c_count_message(const struct i2c_msg i2c_msgs[], int num) +{ + int i; + int size; + + size = sizeof(struct ec_params_i2c_passthru); + size += num * sizeof(struct ec_params_i2c_passthru_msg); + for (i = 0; i < num; i++) + if (!(i2c_msgs[i].flags & I2C_M_RD)) + size += i2c_msgs[i].len; + + return size; +} + +/** + * ec_i2c_construct_message - construct a message to go to the EC + * + * This function effectively stuffs the standard i2c_msg format of Linux into + * a format that the EC understands. + * + * @buf: The buffer to fill. We assume that the buffer is big enough. + * @i2c_msgs: The i2c messages to read. + * @num: The number of i2c messages. + * @bus_num: The remote bus number we want to talk to. + * + * Returns 0 or a negative error number. + */ +static int ec_i2c_construct_message(u8 *buf, const struct i2c_msg i2c_msgs[], + int num, u16 bus_num) +{ + struct ec_params_i2c_passthru *params; + u8 *out_data; + int i; + + out_data = buf + sizeof(struct ec_params_i2c_passthru) + + num * sizeof(struct ec_params_i2c_passthru_msg); + + params = (struct ec_params_i2c_passthru *)buf; + params->port = bus_num; + params->num_msgs = num; + for (i = 0; i < num; i++) { + const struct i2c_msg *i2c_msg = &i2c_msgs[i]; + struct ec_params_i2c_passthru_msg *msg = ¶ms->msg[i]; + + msg->len = i2c_msg->len; + msg->addr_flags = i2c_msg->addr; + + if (i2c_msg->flags & I2C_M_TEN) + return -EINVAL; + + if (i2c_msg->flags & I2C_M_RD) { + msg->addr_flags |= EC_I2C_FLAG_READ; + } else { + memcpy(out_data, i2c_msg->buf, msg->len); + out_data += msg->len; + } + } + + return 0; +} + +/** + * ec_i2c_count_response - Count bytes needed for ec_i2c_parse_response + * + * @i2c_msgs: The i2c messages to fill up. + * @num: The number of i2c messages expected. + * + * Returns the number of response bytes expeced. + */ +static int ec_i2c_count_response(struct i2c_msg i2c_msgs[], int num) +{ + int size; + int i; + + size = sizeof(struct ec_response_i2c_passthru); + for (i = 0; i < num; i++) + if (i2c_msgs[i].flags & I2C_M_RD) + size += i2c_msgs[i].len; + + return size; +} + +/** + * ec_i2c_parse_response - Parse a response from the EC + * + * We'll take the EC's response and copy it back into msgs. + * + * @buf: The buffer to parse. + * @i2c_msgs: The i2c messages to fill up. + * @num: The number of i2c messages; will be modified to include the actual + * number received. + * + * Returns 0 or a negative error number. + */ +static int ec_i2c_parse_response(const u8 *buf, struct i2c_msg i2c_msgs[], + int *num) +{ + const struct ec_response_i2c_passthru *resp; + const u8 *in_data; + int i; + + in_data = buf + sizeof(struct ec_response_i2c_passthru); + + resp = (const struct ec_response_i2c_passthru *)buf; + if (resp->i2c_status & EC_I2C_STATUS_TIMEOUT) + return -ETIMEDOUT; + else if (resp->i2c_status & EC_I2C_STATUS_NAK) + return -ENXIO; + else if (resp->i2c_status & EC_I2C_STATUS_ERROR) + return -EIO; + + /* Other side could send us back fewer messages, but not more */ + if (resp->num_msgs > *num) + return -EPROTO; + *num = resp->num_msgs; + + for (i = 0; i < *num; i++) { + struct i2c_msg *i2c_msg = &i2c_msgs[i]; + + if (i2c_msgs[i].flags & I2C_M_RD) { + memcpy(i2c_msg->buf, in_data, i2c_msg->len); + in_data += i2c_msg->len; + } + } + + return 0; +} + +static int ec_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg i2c_msgs[], + int num) +{ + struct ec_i2c_device *bus = adap->algo_data; + struct device *dev = bus->dev; + const u16 bus_num = bus->remote_bus; + int request_len; + int response_len; + int alloc_size; + int result; + struct cros_ec_command *msg; + + request_len = ec_i2c_count_message(i2c_msgs, num); + if (request_len < 0) { + dev_warn(dev, "Error constructing message %d\n", request_len); + return request_len; + } + + response_len = ec_i2c_count_response(i2c_msgs, num); + if (response_len < 0) { + /* Unexpected; no errors should come when NULL response */ + dev_warn(dev, "Error preparing response %d\n", response_len); + return response_len; + } + + alloc_size = max(request_len, response_len); + msg = kmalloc(sizeof(*msg) + alloc_size, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + result = ec_i2c_construct_message(msg->data, i2c_msgs, num, bus_num); + if (result) { + dev_err(dev, "Error constructing EC i2c message %d\n", result); + goto exit; + } + + msg->version = 0; + msg->command = EC_CMD_I2C_PASSTHRU; + msg->outsize = request_len; + msg->insize = response_len; + + result = cros_ec_cmd_xfer_status(bus->ec, msg); + if (result < 0) { + dev_err(dev, "Error transferring EC i2c message %d\n", result); + goto exit; + } + + result = ec_i2c_parse_response(msg->data, i2c_msgs, &num); + if (result < 0) + goto exit; + + /* Indicate success by saying how many messages were sent */ + result = num; +exit: + kfree(msg); + return result; +} + +static u32 ec_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm ec_i2c_algorithm = { + .master_xfer = ec_i2c_xfer, + .functionality = ec_i2c_functionality, +}; + +static int ec_i2c_probe(struct platform_device *pdev) +{ + struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent); + struct device *dev = &pdev->dev; + struct ec_i2c_device *bus = NULL; + u32 remote_bus; + int err; + + if (!ec->cmd_xfer) { + dev_err(dev, "Missing sendrecv\n"); + return -EINVAL; + } + + bus = devm_kzalloc(dev, sizeof(*bus), GFP_KERNEL); + if (bus == NULL) + return -ENOMEM; + + err = device_property_read_u32(dev, "google,remote-bus", &remote_bus); + if (err) { + dev_err(dev, "Couldn't read remote-bus property\n"); + return err; + } + bus->remote_bus = remote_bus; + + bus->ec = ec; + bus->dev = dev; + + bus->adap.owner = THIS_MODULE; + strscpy(bus->adap.name, "cros-ec-i2c-tunnel", sizeof(bus->adap.name)); + bus->adap.algo = &ec_i2c_algorithm; + bus->adap.algo_data = bus; + bus->adap.dev.parent = &pdev->dev; + bus->adap.dev.of_node = pdev->dev.of_node; + bus->adap.retries = I2C_MAX_RETRIES; + ACPI_COMPANION_SET(&bus->adap.dev, ACPI_COMPANION(&pdev->dev)); + + err = i2c_add_adapter(&bus->adap); + if (err) + return err; + platform_set_drvdata(pdev, bus); + + return err; +} + +static void ec_i2c_remove(struct platform_device *dev) +{ + struct ec_i2c_device *bus = platform_get_drvdata(dev); + + i2c_del_adapter(&bus->adap); +} + +static const struct of_device_id cros_ec_i2c_of_match[] __maybe_unused = { + { .compatible = "google,cros-ec-i2c-tunnel" }, + {}, +}; +MODULE_DEVICE_TABLE(of, cros_ec_i2c_of_match); + +static const struct acpi_device_id cros_ec_i2c_tunnel_acpi_id[] __maybe_unused = { + { "GOOG0012", 0 }, + { } +}; +MODULE_DEVICE_TABLE(acpi, cros_ec_i2c_tunnel_acpi_id); + +static struct platform_driver ec_i2c_tunnel_driver = { + .probe = ec_i2c_probe, + .remove_new = ec_i2c_remove, + .driver = { + .name = "cros-ec-i2c-tunnel", + .acpi_match_table = ACPI_PTR(cros_ec_i2c_tunnel_acpi_id), + .of_match_table = of_match_ptr(cros_ec_i2c_of_match), + }, +}; + +module_platform_driver(ec_i2c_tunnel_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("EC I2C tunnel driver"); +MODULE_ALIAS("platform:cros-ec-i2c-tunnel"); diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c new file mode 100644 index 000000000..02b3b1160 --- /dev/null +++ b/drivers/i2c/busses/i2c-davinci.c @@ -0,0 +1,964 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * TI DAVINCI I2C adapter driver. + * + * Copyright (C) 2006 Texas Instruments. + * Copyright (C) 2007 MontaVista Software Inc. + * + * Updated by Vinod & Sudhakar Feb 2005 + * + * ---------------------------------------------------------------------------- + * + * ---------------------------------------------------------------------------- + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/clk.h> +#include <linux/errno.h> +#include <linux/sched.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/cpufreq.h> +#include <linux/gpio/consumer.h> +#include <linux/of.h> +#include <linux/platform_data/i2c-davinci.h> +#include <linux/pm_runtime.h> + +/* ----- global defines ----------------------------------------------- */ + +#define DAVINCI_I2C_TIMEOUT (1*HZ) +#define DAVINCI_I2C_MAX_TRIES 2 +#define DAVINCI_I2C_OWN_ADDRESS 0x08 +#define I2C_DAVINCI_INTR_ALL (DAVINCI_I2C_IMR_SCD | \ + DAVINCI_I2C_IMR_ARDY | \ + DAVINCI_I2C_IMR_NACK | \ + DAVINCI_I2C_IMR_AL) + +#define DAVINCI_I2C_OAR_REG 0x00 +#define DAVINCI_I2C_IMR_REG 0x04 +#define DAVINCI_I2C_STR_REG 0x08 +#define DAVINCI_I2C_CLKL_REG 0x0c +#define DAVINCI_I2C_CLKH_REG 0x10 +#define DAVINCI_I2C_CNT_REG 0x14 +#define DAVINCI_I2C_DRR_REG 0x18 +#define DAVINCI_I2C_SAR_REG 0x1c +#define DAVINCI_I2C_DXR_REG 0x20 +#define DAVINCI_I2C_MDR_REG 0x24 +#define DAVINCI_I2C_IVR_REG 0x28 +#define DAVINCI_I2C_EMDR_REG 0x2c +#define DAVINCI_I2C_PSC_REG 0x30 +#define DAVINCI_I2C_FUNC_REG 0x48 +#define DAVINCI_I2C_DIR_REG 0x4c +#define DAVINCI_I2C_DIN_REG 0x50 +#define DAVINCI_I2C_DOUT_REG 0x54 +#define DAVINCI_I2C_DSET_REG 0x58 +#define DAVINCI_I2C_DCLR_REG 0x5c + +#define DAVINCI_I2C_IVR_AAS 0x07 +#define DAVINCI_I2C_IVR_SCD 0x06 +#define DAVINCI_I2C_IVR_XRDY 0x05 +#define DAVINCI_I2C_IVR_RDR 0x04 +#define DAVINCI_I2C_IVR_ARDY 0x03 +#define DAVINCI_I2C_IVR_NACK 0x02 +#define DAVINCI_I2C_IVR_AL 0x01 + +#define DAVINCI_I2C_STR_BB BIT(12) +#define DAVINCI_I2C_STR_RSFULL BIT(11) +#define DAVINCI_I2C_STR_SCD BIT(5) +#define DAVINCI_I2C_STR_ARDY BIT(2) +#define DAVINCI_I2C_STR_NACK BIT(1) +#define DAVINCI_I2C_STR_AL BIT(0) + +#define DAVINCI_I2C_MDR_NACK BIT(15) +#define DAVINCI_I2C_MDR_STT BIT(13) +#define DAVINCI_I2C_MDR_STP BIT(11) +#define DAVINCI_I2C_MDR_MST BIT(10) +#define DAVINCI_I2C_MDR_TRX BIT(9) +#define DAVINCI_I2C_MDR_XA BIT(8) +#define DAVINCI_I2C_MDR_RM BIT(7) +#define DAVINCI_I2C_MDR_IRS BIT(5) + +#define DAVINCI_I2C_IMR_AAS BIT(6) +#define DAVINCI_I2C_IMR_SCD BIT(5) +#define DAVINCI_I2C_IMR_XRDY BIT(4) +#define DAVINCI_I2C_IMR_RRDY BIT(3) +#define DAVINCI_I2C_IMR_ARDY BIT(2) +#define DAVINCI_I2C_IMR_NACK BIT(1) +#define DAVINCI_I2C_IMR_AL BIT(0) + +/* set SDA and SCL as GPIO */ +#define DAVINCI_I2C_FUNC_PFUNC0 BIT(0) + +/* set SCL as output when used as GPIO*/ +#define DAVINCI_I2C_DIR_PDIR0 BIT(0) +/* set SDA as output when used as GPIO*/ +#define DAVINCI_I2C_DIR_PDIR1 BIT(1) + +/* read SCL GPIO level */ +#define DAVINCI_I2C_DIN_PDIN0 BIT(0) +/* read SDA GPIO level */ +#define DAVINCI_I2C_DIN_PDIN1 BIT(1) + +/*set the SCL GPIO high */ +#define DAVINCI_I2C_DSET_PDSET0 BIT(0) +/*set the SDA GPIO high */ +#define DAVINCI_I2C_DSET_PDSET1 BIT(1) + +/* set the SCL GPIO low */ +#define DAVINCI_I2C_DCLR_PDCLR0 BIT(0) +/* set the SDA GPIO low */ +#define DAVINCI_I2C_DCLR_PDCLR1 BIT(1) + +/* timeout for pm runtime autosuspend */ +#define DAVINCI_I2C_PM_TIMEOUT 1000 /* ms */ + +struct davinci_i2c_dev { + struct device *dev; + void __iomem *base; + struct completion cmd_complete; + struct clk *clk; + int cmd_err; + u8 *buf; + size_t buf_len; + int irq; + int stop; + u8 terminate; + struct i2c_adapter adapter; +#ifdef CONFIG_CPU_FREQ + struct notifier_block freq_transition; +#endif + struct davinci_i2c_platform_data *pdata; +}; + +/* default platform data to use if not supplied in the platform_device */ +static struct davinci_i2c_platform_data davinci_i2c_platform_data_default = { + .bus_freq = 100, + .bus_delay = 0, +}; + +static inline void davinci_i2c_write_reg(struct davinci_i2c_dev *i2c_dev, + int reg, u16 val) +{ + writew_relaxed(val, i2c_dev->base + reg); +} + +static inline u16 davinci_i2c_read_reg(struct davinci_i2c_dev *i2c_dev, int reg) +{ + return readw_relaxed(i2c_dev->base + reg); +} + +static inline void davinci_i2c_reset_ctrl(struct davinci_i2c_dev *i2c_dev, + int val) +{ + u16 w; + + w = davinci_i2c_read_reg(i2c_dev, DAVINCI_I2C_MDR_REG); + if (!val) /* put I2C into reset */ + w &= ~DAVINCI_I2C_MDR_IRS; + else /* take I2C out of reset */ + w |= DAVINCI_I2C_MDR_IRS; + + davinci_i2c_write_reg(i2c_dev, DAVINCI_I2C_MDR_REG, w); +} + +static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev) +{ + struct davinci_i2c_platform_data *pdata = dev->pdata; + u16 psc; + u32 clk; + u32 d; + u32 clkh; + u32 clkl; + u32 input_clock = clk_get_rate(dev->clk); + struct device_node *of_node = dev->dev->of_node; + + /* NOTE: I2C Clock divider programming info + * As per I2C specs the following formulas provide prescaler + * and low/high divider values + * input clk --> PSC Div -----------> ICCL/H Div --> output clock + * module clk + * + * output clk = module clk / (PSC + 1) [ (ICCL + d) + (ICCH + d) ] + * + * Thus, + * (ICCL + ICCH) = clk = (input clk / ((psc +1) * output clk)) - 2d; + * + * where if PSC == 0, d = 7, + * if PSC == 1, d = 6 + * if PSC > 1 , d = 5 + * + * Note: + * d is always 6 on Keystone I2C controller + */ + + /* + * Both Davinci and current Keystone User Guides recommend a value + * between 7MHz and 12MHz. In reality 7MHz module clock doesn't + * always produce enough margin between SDA and SCL transitions. + * Measurements show that the higher the module clock is, the + * bigger is the margin, providing more reliable communication. + * So we better target for 12MHz. + */ + psc = (input_clock / 12000000) - 1; + if ((input_clock / (psc + 1)) > 12000000) + psc++; /* better to run under spec than over */ + d = (psc >= 2) ? 5 : 7 - psc; + + if (of_node && of_device_is_compatible(of_node, "ti,keystone-i2c")) + d = 6; + + clk = ((input_clock / (psc + 1)) / (pdata->bus_freq * 1000)); + /* Avoid driving the bus too fast because of rounding errors above */ + if (input_clock / (psc + 1) / clk > pdata->bus_freq * 1000) + clk++; + /* + * According to I2C-BUS Spec 2.1, in FAST-MODE LOW period should be at + * least 1.3uS, which is not the case with 50% duty cycle. Driving HIGH + * to LOW ratio as 1 to 2 is more safe. + */ + if (pdata->bus_freq > 100) + clkl = (clk << 1) / 3; + else + clkl = (clk >> 1); + /* + * It's not always possible to have 1 to 2 ratio when d=7, so fall back + * to minimal possible clkh in this case. + * + * Note: + * CLKH is not allowed to be 0, in this case I2C clock is not generated + * at all + */ + if (clk > clkl + d) { + clkh = clk - clkl - d; + clkl -= d; + } else { + clkh = 1; + clkl = clk - (d << 1); + } + + davinci_i2c_write_reg(dev, DAVINCI_I2C_PSC_REG, psc); + davinci_i2c_write_reg(dev, DAVINCI_I2C_CLKH_REG, clkh); + davinci_i2c_write_reg(dev, DAVINCI_I2C_CLKL_REG, clkl); + + dev_dbg(dev->dev, "input_clock = %d, CLK = %d\n", input_clock, clk); +} + +/* + * This function configures I2C and brings I2C out of reset. + * This function is called during I2C init function. This function + * also gets called if I2C encounters any errors. + */ +static int i2c_davinci_init(struct davinci_i2c_dev *dev) +{ + struct davinci_i2c_platform_data *pdata = dev->pdata; + + /* put I2C into reset */ + davinci_i2c_reset_ctrl(dev, 0); + + /* compute clock dividers */ + i2c_davinci_calc_clk_dividers(dev); + + /* Respond at reserved "SMBus Host" slave address" (and zero); + * we seem to have no option to not respond... + */ + davinci_i2c_write_reg(dev, DAVINCI_I2C_OAR_REG, DAVINCI_I2C_OWN_ADDRESS); + + dev_dbg(dev->dev, "PSC = %d\n", + davinci_i2c_read_reg(dev, DAVINCI_I2C_PSC_REG)); + dev_dbg(dev->dev, "CLKL = %d\n", + davinci_i2c_read_reg(dev, DAVINCI_I2C_CLKL_REG)); + dev_dbg(dev->dev, "CLKH = %d\n", + davinci_i2c_read_reg(dev, DAVINCI_I2C_CLKH_REG)); + dev_dbg(dev->dev, "bus_freq = %dkHz, bus_delay = %d\n", + pdata->bus_freq, pdata->bus_delay); + + + /* Take the I2C module out of reset: */ + davinci_i2c_reset_ctrl(dev, 1); + + /* Enable interrupts */ + davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, I2C_DAVINCI_INTR_ALL); + + return 0; +} + +/* + * This routine does i2c bus recovery by using i2c_generic_scl_recovery + * which is provided by I2C Bus recovery infrastructure. + */ +static void davinci_i2c_prepare_recovery(struct i2c_adapter *adap) +{ + struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); + + /* Disable interrupts */ + davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, 0); + + /* put I2C into reset */ + davinci_i2c_reset_ctrl(dev, 0); +} + +static void davinci_i2c_unprepare_recovery(struct i2c_adapter *adap) +{ + struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); + + i2c_davinci_init(dev); +} + +static struct i2c_bus_recovery_info davinci_i2c_gpio_recovery_info = { + .recover_bus = i2c_generic_scl_recovery, + .prepare_recovery = davinci_i2c_prepare_recovery, + .unprepare_recovery = davinci_i2c_unprepare_recovery, +}; + +static void davinci_i2c_set_scl(struct i2c_adapter *adap, int val) +{ + struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); + + if (val) + davinci_i2c_write_reg(dev, DAVINCI_I2C_DSET_REG, + DAVINCI_I2C_DSET_PDSET0); + else + davinci_i2c_write_reg(dev, DAVINCI_I2C_DCLR_REG, + DAVINCI_I2C_DCLR_PDCLR0); +} + +static int davinci_i2c_get_scl(struct i2c_adapter *adap) +{ + struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); + int val; + + /* read the state of SCL */ + val = davinci_i2c_read_reg(dev, DAVINCI_I2C_DIN_REG); + return val & DAVINCI_I2C_DIN_PDIN0; +} + +static int davinci_i2c_get_sda(struct i2c_adapter *adap) +{ + struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); + int val; + + /* read the state of SDA */ + val = davinci_i2c_read_reg(dev, DAVINCI_I2C_DIN_REG); + return val & DAVINCI_I2C_DIN_PDIN1; +} + +static void davinci_i2c_scl_prepare_recovery(struct i2c_adapter *adap) +{ + struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); + + davinci_i2c_prepare_recovery(adap); + + /* SCL output, SDA input */ + davinci_i2c_write_reg(dev, DAVINCI_I2C_DIR_REG, DAVINCI_I2C_DIR_PDIR0); + + /* change to GPIO mode */ + davinci_i2c_write_reg(dev, DAVINCI_I2C_FUNC_REG, + DAVINCI_I2C_FUNC_PFUNC0); +} + +static void davinci_i2c_scl_unprepare_recovery(struct i2c_adapter *adap) +{ + struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); + + /* change back to I2C mode */ + davinci_i2c_write_reg(dev, DAVINCI_I2C_FUNC_REG, 0); + + davinci_i2c_unprepare_recovery(adap); +} + +static struct i2c_bus_recovery_info davinci_i2c_scl_recovery_info = { + .recover_bus = i2c_generic_scl_recovery, + .set_scl = davinci_i2c_set_scl, + .get_scl = davinci_i2c_get_scl, + .get_sda = davinci_i2c_get_sda, + .prepare_recovery = davinci_i2c_scl_prepare_recovery, + .unprepare_recovery = davinci_i2c_scl_unprepare_recovery, +}; + +/* + * Waiting for bus not busy + */ +static int i2c_davinci_wait_bus_not_busy(struct davinci_i2c_dev *dev) +{ + unsigned long timeout = jiffies + dev->adapter.timeout; + + do { + if (!(davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG) & DAVINCI_I2C_STR_BB)) + return 0; + schedule_timeout_uninterruptible(1); + } while (time_before_eq(jiffies, timeout)); + + dev_warn(dev->dev, "timeout waiting for bus ready\n"); + i2c_recover_bus(&dev->adapter); + + /* + * if bus is still "busy" here, it's most probably a HW problem like + * short-circuit + */ + if (davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG) & DAVINCI_I2C_STR_BB) + return -EIO; + + return 0; +} + +/* + * Low level master read/write transaction. This function is called + * from i2c_davinci_xfer. + */ +static int +i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop) +{ + struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); + struct davinci_i2c_platform_data *pdata = dev->pdata; + u32 flag; + u16 w; + unsigned long time_left; + + if (msg->addr == DAVINCI_I2C_OWN_ADDRESS) { + dev_warn(dev->dev, "transfer to own address aborted\n"); + return -EADDRNOTAVAIL; + } + + /* Introduce a delay, required for some boards (e.g Davinci EVM) */ + if (pdata->bus_delay) + udelay(pdata->bus_delay); + + /* set the slave address */ + davinci_i2c_write_reg(dev, DAVINCI_I2C_SAR_REG, msg->addr); + + dev->buf = msg->buf; + dev->buf_len = msg->len; + dev->stop = stop; + + davinci_i2c_write_reg(dev, DAVINCI_I2C_CNT_REG, dev->buf_len); + + reinit_completion(&dev->cmd_complete); + dev->cmd_err = 0; + + /* Take I2C out of reset and configure it as master */ + flag = DAVINCI_I2C_MDR_IRS | DAVINCI_I2C_MDR_MST; + + /* if the slave address is ten bit address, enable XA bit */ + if (msg->flags & I2C_M_TEN) + flag |= DAVINCI_I2C_MDR_XA; + if (!(msg->flags & I2C_M_RD)) + flag |= DAVINCI_I2C_MDR_TRX; + if (msg->len == 0) + flag |= DAVINCI_I2C_MDR_RM; + + /* Enable receive or transmit interrupts */ + w = davinci_i2c_read_reg(dev, DAVINCI_I2C_IMR_REG); + if (msg->flags & I2C_M_RD) + w |= DAVINCI_I2C_IMR_RRDY; + else + w |= DAVINCI_I2C_IMR_XRDY; + davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, w); + + dev->terminate = 0; + + /* + * Write mode register first as needed for correct behaviour + * on OMAP-L138, but don't set STT yet to avoid a race with XRDY + * occurring before we have loaded DXR + */ + davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag); + + /* + * First byte should be set here, not after interrupt, + * because transmit-data-ready interrupt can come before + * NACK-interrupt during sending of previous message and + * ICDXR may have wrong data + * It also saves us one interrupt, slightly faster + */ + if ((!(msg->flags & I2C_M_RD)) && dev->buf_len) { + davinci_i2c_write_reg(dev, DAVINCI_I2C_DXR_REG, *dev->buf++); + dev->buf_len--; + } + + /* Set STT to begin transmit now DXR is loaded */ + flag |= DAVINCI_I2C_MDR_STT; + if (stop && msg->len != 0) + flag |= DAVINCI_I2C_MDR_STP; + davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag); + + time_left = wait_for_completion_timeout(&dev->cmd_complete, + dev->adapter.timeout); + if (!time_left) { + dev_err(dev->dev, "controller timed out\n"); + i2c_recover_bus(adap); + dev->buf_len = 0; + return -ETIMEDOUT; + } + if (dev->buf_len) { + /* This should be 0 if all bytes were transferred + * or dev->cmd_err denotes an error. + */ + dev_err(dev->dev, "abnormal termination buf_len=%zu\n", + dev->buf_len); + dev->terminate = 1; + wmb(); + dev->buf_len = 0; + return -EREMOTEIO; + } + + /* no error */ + if (likely(!dev->cmd_err)) + return msg->len; + + /* We have an error */ + if (dev->cmd_err & DAVINCI_I2C_STR_AL) { + i2c_davinci_init(dev); + return -EIO; + } + + if (dev->cmd_err & DAVINCI_I2C_STR_NACK) { + if (msg->flags & I2C_M_IGNORE_NAK) + return msg->len; + w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); + w |= DAVINCI_I2C_MDR_STP; + davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); + return -EREMOTEIO; + } + return -EIO; +} + +/* + * Prepare controller for a transaction and call i2c_davinci_xfer_msg + */ +static int +i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); + int i; + int ret; + + dev_dbg(dev->dev, "%s: msgs: %d\n", __func__, num); + + ret = pm_runtime_resume_and_get(dev->dev); + if (ret < 0) { + dev_err(dev->dev, "Failed to runtime_get device: %d\n", ret); + return ret; + } + + ret = i2c_davinci_wait_bus_not_busy(dev); + if (ret < 0) { + dev_warn(dev->dev, "timeout waiting for bus ready\n"); + goto out; + } + + for (i = 0; i < num; i++) { + ret = i2c_davinci_xfer_msg(adap, &msgs[i], (i == (num - 1))); + dev_dbg(dev->dev, "%s [%d/%d] ret: %d\n", __func__, i + 1, num, + ret); + if (ret < 0) + goto out; + } + + ret = num; + +out: + pm_runtime_mark_last_busy(dev->dev); + pm_runtime_put_autosuspend(dev->dev); + + return ret; +} + +static u32 i2c_davinci_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static void terminate_read(struct davinci_i2c_dev *dev) +{ + u16 w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); + w |= DAVINCI_I2C_MDR_NACK; + davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); + + /* Throw away data */ + davinci_i2c_read_reg(dev, DAVINCI_I2C_DRR_REG); + if (!dev->terminate) + dev_err(dev->dev, "RDR IRQ while no data requested\n"); +} +static void terminate_write(struct davinci_i2c_dev *dev) +{ + u16 w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); + w |= DAVINCI_I2C_MDR_RM | DAVINCI_I2C_MDR_STP; + davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); + + if (!dev->terminate) + dev_dbg(dev->dev, "TDR IRQ while no data to send\n"); +} + +/* + * Interrupt service routine. This gets called whenever an I2C interrupt + * occurs. + */ +static irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id) +{ + struct davinci_i2c_dev *dev = dev_id; + u32 stat; + int count = 0; + u16 w; + + if (pm_runtime_suspended(dev->dev)) + return IRQ_NONE; + + while ((stat = davinci_i2c_read_reg(dev, DAVINCI_I2C_IVR_REG))) { + dev_dbg(dev->dev, "%s: stat=0x%x\n", __func__, stat); + if (count++ == 100) { + dev_warn(dev->dev, "Too much work in one IRQ\n"); + break; + } + + switch (stat) { + case DAVINCI_I2C_IVR_AL: + /* Arbitration lost, must retry */ + dev->cmd_err |= DAVINCI_I2C_STR_AL; + dev->buf_len = 0; + complete(&dev->cmd_complete); + break; + + case DAVINCI_I2C_IVR_NACK: + dev->cmd_err |= DAVINCI_I2C_STR_NACK; + dev->buf_len = 0; + complete(&dev->cmd_complete); + break; + + case DAVINCI_I2C_IVR_ARDY: + davinci_i2c_write_reg(dev, + DAVINCI_I2C_STR_REG, DAVINCI_I2C_STR_ARDY); + if (((dev->buf_len == 0) && (dev->stop != 0)) || + (dev->cmd_err & DAVINCI_I2C_STR_NACK)) { + w = davinci_i2c_read_reg(dev, + DAVINCI_I2C_MDR_REG); + w |= DAVINCI_I2C_MDR_STP; + davinci_i2c_write_reg(dev, + DAVINCI_I2C_MDR_REG, w); + } + complete(&dev->cmd_complete); + break; + + case DAVINCI_I2C_IVR_RDR: + if (dev->buf_len) { + *dev->buf++ = + davinci_i2c_read_reg(dev, + DAVINCI_I2C_DRR_REG); + dev->buf_len--; + if (dev->buf_len) + continue; + + davinci_i2c_write_reg(dev, + DAVINCI_I2C_STR_REG, + DAVINCI_I2C_IMR_RRDY); + } else { + /* signal can terminate transfer */ + terminate_read(dev); + } + break; + + case DAVINCI_I2C_IVR_XRDY: + if (dev->buf_len) { + davinci_i2c_write_reg(dev, DAVINCI_I2C_DXR_REG, + *dev->buf++); + dev->buf_len--; + if (dev->buf_len) + continue; + + w = davinci_i2c_read_reg(dev, + DAVINCI_I2C_IMR_REG); + w &= ~DAVINCI_I2C_IMR_XRDY; + davinci_i2c_write_reg(dev, + DAVINCI_I2C_IMR_REG, + w); + } else { + /* signal can terminate transfer */ + terminate_write(dev); + } + break; + + case DAVINCI_I2C_IVR_SCD: + davinci_i2c_write_reg(dev, + DAVINCI_I2C_STR_REG, DAVINCI_I2C_STR_SCD); + complete(&dev->cmd_complete); + break; + + case DAVINCI_I2C_IVR_AAS: + dev_dbg(dev->dev, "Address as slave interrupt\n"); + break; + + default: + dev_warn(dev->dev, "Unrecognized irq stat %d\n", stat); + break; + } + } + + return count ? IRQ_HANDLED : IRQ_NONE; +} + +#ifdef CONFIG_CPU_FREQ +static int i2c_davinci_cpufreq_transition(struct notifier_block *nb, + unsigned long val, void *data) +{ + struct davinci_i2c_dev *dev; + + dev = container_of(nb, struct davinci_i2c_dev, freq_transition); + + i2c_lock_bus(&dev->adapter, I2C_LOCK_ROOT_ADAPTER); + if (val == CPUFREQ_PRECHANGE) { + davinci_i2c_reset_ctrl(dev, 0); + } else if (val == CPUFREQ_POSTCHANGE) { + i2c_davinci_calc_clk_dividers(dev); + davinci_i2c_reset_ctrl(dev, 1); + } + i2c_unlock_bus(&dev->adapter, I2C_LOCK_ROOT_ADAPTER); + + return 0; +} + +static inline int i2c_davinci_cpufreq_register(struct davinci_i2c_dev *dev) +{ + dev->freq_transition.notifier_call = i2c_davinci_cpufreq_transition; + + return cpufreq_register_notifier(&dev->freq_transition, + CPUFREQ_TRANSITION_NOTIFIER); +} + +static inline void i2c_davinci_cpufreq_deregister(struct davinci_i2c_dev *dev) +{ + cpufreq_unregister_notifier(&dev->freq_transition, + CPUFREQ_TRANSITION_NOTIFIER); +} +#else +static inline int i2c_davinci_cpufreq_register(struct davinci_i2c_dev *dev) +{ + return 0; +} + +static inline void i2c_davinci_cpufreq_deregister(struct davinci_i2c_dev *dev) +{ +} +#endif + +static const struct i2c_algorithm i2c_davinci_algo = { + .master_xfer = i2c_davinci_xfer, + .functionality = i2c_davinci_func, +}; + +static const struct of_device_id davinci_i2c_of_match[] = { + {.compatible = "ti,davinci-i2c", }, + {.compatible = "ti,keystone-i2c", }, + {}, +}; +MODULE_DEVICE_TABLE(of, davinci_i2c_of_match); + +static int davinci_i2c_probe(struct platform_device *pdev) +{ + struct davinci_i2c_dev *dev; + struct i2c_adapter *adap; + struct i2c_bus_recovery_info *rinfo; + int r, irq; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + + init_completion(&dev->cmd_complete); + + dev->dev = &pdev->dev; + dev->irq = irq; + dev->pdata = dev_get_platdata(&pdev->dev); + platform_set_drvdata(pdev, dev); + + if (!dev->pdata && pdev->dev.of_node) { + u32 prop; + + dev->pdata = devm_kzalloc(&pdev->dev, + sizeof(struct davinci_i2c_platform_data), GFP_KERNEL); + if (!dev->pdata) + return -ENOMEM; + + memcpy(dev->pdata, &davinci_i2c_platform_data_default, + sizeof(struct davinci_i2c_platform_data)); + if (!of_property_read_u32(pdev->dev.of_node, "clock-frequency", + &prop)) + dev->pdata->bus_freq = prop / 1000; + + dev->pdata->has_pfunc = + of_property_read_bool(pdev->dev.of_node, + "ti,has-pfunc"); + } else if (!dev->pdata) { + dev->pdata = &davinci_i2c_platform_data_default; + } + + dev->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(dev->clk)) + return PTR_ERR(dev->clk); + + dev->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(dev->base)) { + return PTR_ERR(dev->base); + } + + pm_runtime_set_autosuspend_delay(dev->dev, + DAVINCI_I2C_PM_TIMEOUT); + pm_runtime_use_autosuspend(dev->dev); + + pm_runtime_enable(dev->dev); + + r = pm_runtime_resume_and_get(dev->dev); + if (r < 0) { + dev_err(dev->dev, "failed to runtime_get device: %d\n", r); + goto err_pm; + } + + i2c_davinci_init(dev); + + r = devm_request_irq(&pdev->dev, dev->irq, i2c_davinci_isr, 0, + pdev->name, dev); + if (r) { + dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq); + goto err_unuse_clocks; + } + + r = i2c_davinci_cpufreq_register(dev); + if (r) { + dev_err(&pdev->dev, "failed to register cpufreq\n"); + goto err_unuse_clocks; + } + + adap = &dev->adapter; + i2c_set_adapdata(adap, dev); + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_DEPRECATED; + strscpy(adap->name, "DaVinci I2C adapter", sizeof(adap->name)); + adap->algo = &i2c_davinci_algo; + adap->dev.parent = &pdev->dev; + adap->timeout = DAVINCI_I2C_TIMEOUT; + adap->dev.of_node = pdev->dev.of_node; + + if (dev->pdata->has_pfunc) + adap->bus_recovery_info = &davinci_i2c_scl_recovery_info; + else if (dev->pdata->gpio_recovery) { + rinfo = &davinci_i2c_gpio_recovery_info; + adap->bus_recovery_info = rinfo; + rinfo->scl_gpiod = devm_gpiod_get(&pdev->dev, "scl", + GPIOD_OUT_HIGH_OPEN_DRAIN); + if (IS_ERR(rinfo->scl_gpiod)) { + r = PTR_ERR(rinfo->scl_gpiod); + goto err_unuse_clocks; + } + rinfo->sda_gpiod = devm_gpiod_get(&pdev->dev, "sda", GPIOD_IN); + if (IS_ERR(rinfo->sda_gpiod)) { + r = PTR_ERR(rinfo->sda_gpiod); + goto err_unuse_clocks; + } + } + + adap->nr = pdev->id; + r = i2c_add_numbered_adapter(adap); + if (r) + goto err_unuse_clocks; + + pm_runtime_mark_last_busy(dev->dev); + pm_runtime_put_autosuspend(dev->dev); + + return 0; + +err_unuse_clocks: + pm_runtime_dont_use_autosuspend(dev->dev); + pm_runtime_put_sync(dev->dev); +err_pm: + pm_runtime_disable(dev->dev); + + return r; +} + +static void davinci_i2c_remove(struct platform_device *pdev) +{ + struct davinci_i2c_dev *dev = platform_get_drvdata(pdev); + int ret; + + i2c_davinci_cpufreq_deregister(dev); + + i2c_del_adapter(&dev->adapter); + + ret = pm_runtime_get_sync(&pdev->dev); + if (ret < 0) + dev_err(&pdev->dev, "Failed to resume device\n"); + else + davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, 0); + + pm_runtime_dont_use_autosuspend(dev->dev); + pm_runtime_put_sync(dev->dev); + pm_runtime_disable(dev->dev); +} + +static int davinci_i2c_suspend(struct device *dev) +{ + struct davinci_i2c_dev *i2c_dev = dev_get_drvdata(dev); + + /* put I2C into reset */ + davinci_i2c_reset_ctrl(i2c_dev, 0); + + return 0; +} + +static int davinci_i2c_resume(struct device *dev) +{ + struct davinci_i2c_dev *i2c_dev = dev_get_drvdata(dev); + + /* take I2C out of reset */ + davinci_i2c_reset_ctrl(i2c_dev, 1); + + return 0; +} + +static const struct dev_pm_ops davinci_i2c_pm = { + .suspend = davinci_i2c_suspend, + .resume = davinci_i2c_resume, + NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) +}; + +static const struct platform_device_id davinci_i2c_driver_ids[] = { + { .name = "i2c_davinci", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(platform, davinci_i2c_driver_ids); + +static struct platform_driver davinci_i2c_driver = { + .probe = davinci_i2c_probe, + .remove_new = davinci_i2c_remove, + .id_table = davinci_i2c_driver_ids, + .driver = { + .name = "i2c_davinci", + .pm = pm_sleep_ptr(&davinci_i2c_pm), + .of_match_table = davinci_i2c_of_match, + }, +}; + +/* I2C may be needed to bring up other drivers */ +static int __init davinci_i2c_init_driver(void) +{ + return platform_driver_register(&davinci_i2c_driver); +} +subsys_initcall(davinci_i2c_init_driver); + +static void __exit davinci_i2c_exit_driver(void) +{ + platform_driver_unregister(&davinci_i2c_driver); +} +module_exit(davinci_i2c_exit_driver); + +MODULE_AUTHOR("Texas Instruments India"); +MODULE_DESCRIPTION("TI DaVinci I2C bus adapter"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-designware-amdpsp.c b/drivers/i2c/busses/i2c-designware-amdpsp.c new file mode 100644 index 000000000..63454b06e --- /dev/null +++ b/drivers/i2c/busses/i2c-designware-amdpsp.c @@ -0,0 +1,318 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/i2c.h> +#include <linux/pci.h> +#include <linux/psp-platform-access.h> +#include <linux/psp.h> +#include <linux/workqueue.h> + +#include "i2c-designware-core.h" + +#define PSP_I2C_RESERVATION_TIME_MS 100 + +#define PSP_I2C_REQ_RETRY_CNT 400 +#define PSP_I2C_REQ_RETRY_DELAY_US (25 * USEC_PER_MSEC) +#define PSP_I2C_REQ_STS_OK 0x0 +#define PSP_I2C_REQ_STS_BUS_BUSY 0x1 +#define PSP_I2C_REQ_STS_INV_PARAM 0x3 + +enum psp_i2c_req_type { + PSP_I2C_REQ_ACQUIRE, + PSP_I2C_REQ_RELEASE, + PSP_I2C_REQ_MAX +}; + +struct psp_i2c_req { + struct psp_req_buffer_hdr hdr; + enum psp_i2c_req_type type; +}; + +static DEFINE_MUTEX(psp_i2c_access_mutex); +static unsigned long psp_i2c_sem_acquired; +static u32 psp_i2c_access_count; +static bool psp_i2c_mbox_fail; +static struct device *psp_i2c_dev; + +static int (*_psp_send_i2c_req)(struct psp_i2c_req *req); + +/* Helper to verify status returned by PSP */ +static int check_i2c_req_sts(struct psp_i2c_req *req) +{ + u32 status; + + /* Status field in command-response buffer is updated by PSP */ + status = READ_ONCE(req->hdr.status); + + switch (status) { + case PSP_I2C_REQ_STS_OK: + return 0; + case PSP_I2C_REQ_STS_BUS_BUSY: + return -EBUSY; + case PSP_I2C_REQ_STS_INV_PARAM: + default: + return -EIO; + } +} + +/* + * Errors in x86-PSP i2c-arbitration protocol may occur at two levels: + * 1. mailbox communication - PSP is not operational or some IO errors with + * basic communication had happened. + * 2. i2c-requests - PSP refuses to grant i2c arbitration to x86 for too long. + * + * In order to distinguish between these in error handling code all mailbox + * communication errors on the first level (from CCP symbols) will be passed + * up and if -EIO is returned the second level will be checked. + */ +static int psp_send_i2c_req_cezanne(struct psp_i2c_req *req) +{ + int ret; + + ret = psp_send_platform_access_msg(PSP_I2C_REQ_BUS_CMD, (struct psp_request *)req); + if (ret == -EIO) + return check_i2c_req_sts(req); + + return ret; +} + +static int psp_send_i2c_req_doorbell(struct psp_i2c_req *req) +{ + int ret; + + ret = psp_ring_platform_doorbell(req->type, &req->hdr.status); + if (ret == -EIO) + return check_i2c_req_sts(req); + + return ret; +} + +static int psp_send_i2c_req(enum psp_i2c_req_type i2c_req_type) +{ + struct psp_i2c_req *req; + unsigned long start; + int status, ret; + + /* Allocate command-response buffer */ + req = kzalloc(sizeof(*req), GFP_KERNEL); + if (!req) + return -ENOMEM; + + req->hdr.payload_size = sizeof(*req); + req->type = i2c_req_type; + + start = jiffies; + ret = read_poll_timeout(_psp_send_i2c_req, status, + (status != -EBUSY), + PSP_I2C_REQ_RETRY_DELAY_US, + PSP_I2C_REQ_RETRY_CNT * PSP_I2C_REQ_RETRY_DELAY_US, + 0, req); + if (ret) { + dev_err(psp_i2c_dev, "Timed out waiting for PSP to %s I2C bus\n", + (i2c_req_type == PSP_I2C_REQ_ACQUIRE) ? + "release" : "acquire"); + goto cleanup; + } + + ret = status; + if (ret) { + dev_err(psp_i2c_dev, "PSP communication error\n"); + goto cleanup; + } + + dev_dbg(psp_i2c_dev, "Request accepted by PSP after %ums\n", + jiffies_to_msecs(jiffies - start)); + +cleanup: + if (ret) { + dev_err(psp_i2c_dev, "Assume i2c bus is for exclusive host usage\n"); + psp_i2c_mbox_fail = true; + } + + kfree(req); + return ret; +} + +static void release_bus(void) +{ + int status; + + if (!psp_i2c_sem_acquired) + return; + + status = psp_send_i2c_req(PSP_I2C_REQ_RELEASE); + if (status) + return; + + dev_dbg(psp_i2c_dev, "PSP semaphore held for %ums\n", + jiffies_to_msecs(jiffies - psp_i2c_sem_acquired)); + + psp_i2c_sem_acquired = 0; +} + +static void psp_release_i2c_bus_deferred(struct work_struct *work) +{ + mutex_lock(&psp_i2c_access_mutex); + + /* + * If there is any pending transaction, cannot release the bus here. + * psp_release_i2c_bus will take care of this later. + */ + if (psp_i2c_access_count) + goto cleanup; + + release_bus(); + +cleanup: + mutex_unlock(&psp_i2c_access_mutex); +} +static DECLARE_DELAYED_WORK(release_queue, psp_release_i2c_bus_deferred); + +static int psp_acquire_i2c_bus(void) +{ + int status; + + mutex_lock(&psp_i2c_access_mutex); + + /* Return early if mailbox malfunctioned */ + if (psp_i2c_mbox_fail) + goto cleanup; + + psp_i2c_access_count++; + + /* + * No need to request bus arbitration once we are inside semaphore + * reservation period. + */ + if (psp_i2c_sem_acquired) + goto cleanup; + + status = psp_send_i2c_req(PSP_I2C_REQ_ACQUIRE); + if (status) + goto cleanup; + + psp_i2c_sem_acquired = jiffies; + + schedule_delayed_work(&release_queue, + msecs_to_jiffies(PSP_I2C_RESERVATION_TIME_MS)); + + /* + * In case of errors with PSP arbitrator psp_i2c_mbox_fail variable is + * set above. As a consequence consecutive calls to acquire will bypass + * communication with PSP. At any case i2c bus is granted to the caller, + * thus always return success. + */ +cleanup: + mutex_unlock(&psp_i2c_access_mutex); + return 0; +} + +static void psp_release_i2c_bus(void) +{ + mutex_lock(&psp_i2c_access_mutex); + + /* Return early if mailbox was malfunctional */ + if (psp_i2c_mbox_fail) + goto cleanup; + + /* + * If we are last owner of PSP semaphore, need to release aribtration + * via mailbox. + */ + psp_i2c_access_count--; + if (psp_i2c_access_count) + goto cleanup; + + /* + * Send a release command to PSP if the semaphore reservation timeout + * elapsed but x86 still owns the controller. + */ + if (!delayed_work_pending(&release_queue)) + release_bus(); + +cleanup: + mutex_unlock(&psp_i2c_access_mutex); +} + +/* + * Locking methods are based on the default implementation from + * drivers/i2c/i2c-core-base.c, but with psp acquire and release operations + * added. With this in place we can ensure that i2c clients on the bus shared + * with psp are able to lock HW access to the bus for arbitrary number of + * operations - that is e.g. write-wait-read. + */ +static void i2c_adapter_dw_psp_lock_bus(struct i2c_adapter *adapter, + unsigned int flags) +{ + psp_acquire_i2c_bus(); + rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter)); +} + +static int i2c_adapter_dw_psp_trylock_bus(struct i2c_adapter *adapter, + unsigned int flags) +{ + int ret; + + ret = rt_mutex_trylock(&adapter->bus_lock); + if (ret) + return ret; + + psp_acquire_i2c_bus(); + + return ret; +} + +static void i2c_adapter_dw_psp_unlock_bus(struct i2c_adapter *adapter, + unsigned int flags) +{ + psp_release_i2c_bus(); + rt_mutex_unlock(&adapter->bus_lock); +} + +static const struct i2c_lock_operations i2c_dw_psp_lock_ops = { + .lock_bus = i2c_adapter_dw_psp_lock_bus, + .trylock_bus = i2c_adapter_dw_psp_trylock_bus, + .unlock_bus = i2c_adapter_dw_psp_unlock_bus, +}; + +int i2c_dw_amdpsp_probe_lock_support(struct dw_i2c_dev *dev) +{ + struct pci_dev *rdev; + + if (!IS_REACHABLE(CONFIG_CRYPTO_DEV_CCP_DD)) + return -ENODEV; + + if (!dev) + return -ENODEV; + + if (!(dev->flags & ARBITRATION_SEMAPHORE)) + return -ENODEV; + + /* Allow to bind only one instance of a driver */ + if (psp_i2c_dev) + return -EEXIST; + + /* Cezanne uses platform mailbox, Mendocino and later use doorbell */ + rdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0)); + if (rdev->device == 0x1630) + _psp_send_i2c_req = psp_send_i2c_req_cezanne; + else + _psp_send_i2c_req = psp_send_i2c_req_doorbell; + pci_dev_put(rdev); + + if (psp_check_platform_access_status()) + return -EPROBE_DEFER; + + psp_i2c_dev = dev->dev; + + dev_info(psp_i2c_dev, "I2C bus managed by AMD PSP\n"); + + /* + * Install global locking callbacks for adapter as well as internal i2c + * controller locks. + */ + dev->adapter.lock_ops = &i2c_dw_psp_lock_ops; + dev->acquire_lock = psp_acquire_i2c_bus; + dev->release_lock = psp_release_i2c_bus; + + return 0; +} diff --git a/drivers/i2c/busses/i2c-designware-baytrail.c b/drivers/i2c/busses/i2c-designware-baytrail.c new file mode 100644 index 000000000..45774aa47 --- /dev/null +++ b/drivers/i2c/busses/i2c-designware-baytrail.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Intel BayTrail PMIC I2C bus semaphore implementation + * Copyright (c) 2014, Intel Corporation. + */ +#include <linux/device.h> +#include <linux/acpi.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> + +#include <asm/iosf_mbi.h> + +#include "i2c-designware-core.h" + +int i2c_dw_baytrail_probe_lock_support(struct dw_i2c_dev *dev) +{ + acpi_status status; + unsigned long long shared_host = 0; + acpi_handle handle; + + if (!dev) + return -ENODEV; + + handle = ACPI_HANDLE(dev->dev); + if (!handle) + return -ENODEV; + + status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host); + if (ACPI_FAILURE(status)) + return -ENODEV; + + if (!shared_host) + return -ENODEV; + + if (!iosf_mbi_available()) + return -EPROBE_DEFER; + + dev_info(dev->dev, "I2C bus managed by PUNIT\n"); + dev->acquire_lock = iosf_mbi_block_punit_i2c_access; + dev->release_lock = iosf_mbi_unblock_punit_i2c_access; + dev->shared_with_punit = true; + + return 0; +} diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c new file mode 100644 index 000000000..35f762872 --- /dev/null +++ b/drivers/i2c/busses/i2c-designware-common.c @@ -0,0 +1,658 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Synopsys DesignWare I2C adapter driver. + * + * Based on the TI DAVINCI I2C adapter driver. + * + * Copyright (C) 2006 Texas Instruments. + * Copyright (C) 2007 MontaVista Software Inc. + * Copyright (C) 2009 Provigent Ltd. + */ +#include <linux/acpi.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/export.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pm_runtime.h> +#include <linux/regmap.h> +#include <linux/swab.h> +#include <linux/types.h> +#include <linux/units.h> + +#include "i2c-designware-core.h" + +static char *abort_sources[] = { + [ABRT_7B_ADDR_NOACK] = + "slave address not acknowledged (7bit mode)", + [ABRT_10ADDR1_NOACK] = + "first address byte not acknowledged (10bit mode)", + [ABRT_10ADDR2_NOACK] = + "second address byte not acknowledged (10bit mode)", + [ABRT_TXDATA_NOACK] = + "data not acknowledged", + [ABRT_GCALL_NOACK] = + "no acknowledgement for a general call", + [ABRT_GCALL_READ] = + "read after general call", + [ABRT_SBYTE_ACKDET] = + "start byte acknowledged", + [ABRT_SBYTE_NORSTRT] = + "trying to send start byte when restart is disabled", + [ABRT_10B_RD_NORSTRT] = + "trying to read when restart is disabled (10bit mode)", + [ABRT_MASTER_DIS] = + "trying to use disabled adapter", + [ARB_LOST] = + "lost arbitration", + [ABRT_SLAVE_FLUSH_TXFIFO] = + "read command so flush old data in the TX FIFO", + [ABRT_SLAVE_ARBLOST] = + "slave lost the bus while transmitting data to a remote master", + [ABRT_SLAVE_RD_INTX] = + "incorrect slave-transmitter mode configuration", +}; + +static int dw_reg_read(void *context, unsigned int reg, unsigned int *val) +{ + struct dw_i2c_dev *dev = context; + + *val = readl(dev->base + reg); + + return 0; +} + +static int dw_reg_write(void *context, unsigned int reg, unsigned int val) +{ + struct dw_i2c_dev *dev = context; + + writel(val, dev->base + reg); + + return 0; +} + +static int dw_reg_read_swab(void *context, unsigned int reg, unsigned int *val) +{ + struct dw_i2c_dev *dev = context; + + *val = swab32(readl(dev->base + reg)); + + return 0; +} + +static int dw_reg_write_swab(void *context, unsigned int reg, unsigned int val) +{ + struct dw_i2c_dev *dev = context; + + writel(swab32(val), dev->base + reg); + + return 0; +} + +static int dw_reg_read_word(void *context, unsigned int reg, unsigned int *val) +{ + struct dw_i2c_dev *dev = context; + + *val = readw(dev->base + reg) | + (readw(dev->base + reg + 2) << 16); + + return 0; +} + +static int dw_reg_write_word(void *context, unsigned int reg, unsigned int val) +{ + struct dw_i2c_dev *dev = context; + + writew(val, dev->base + reg); + writew(val >> 16, dev->base + reg + 2); + + return 0; +} + +/** + * i2c_dw_init_regmap() - Initialize registers map + * @dev: device private data + * + * Autodetects needed register access mode and creates the regmap with + * corresponding read/write callbacks. This must be called before doing any + * other register access. + */ +int i2c_dw_init_regmap(struct dw_i2c_dev *dev) +{ + struct regmap_config map_cfg = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .disable_locking = true, + .reg_read = dw_reg_read, + .reg_write = dw_reg_write, + .max_register = DW_IC_COMP_TYPE, + }; + u32 reg; + int ret; + + /* + * Skip detecting the registers map configuration if the regmap has + * already been provided by a higher code. + */ + if (dev->map) + return 0; + + ret = i2c_dw_acquire_lock(dev); + if (ret) + return ret; + + reg = readl(dev->base + DW_IC_COMP_TYPE); + i2c_dw_release_lock(dev); + + if ((dev->flags & MODEL_MASK) == MODEL_AMD_NAVI_GPU) + map_cfg.max_register = AMD_UCSI_INTR_REG; + + if (reg == swab32(DW_IC_COMP_TYPE_VALUE)) { + map_cfg.reg_read = dw_reg_read_swab; + map_cfg.reg_write = dw_reg_write_swab; + } else if (reg == (DW_IC_COMP_TYPE_VALUE & 0x0000ffff)) { + map_cfg.reg_read = dw_reg_read_word; + map_cfg.reg_write = dw_reg_write_word; + } else if (reg != DW_IC_COMP_TYPE_VALUE) { + dev_err(dev->dev, + "Unknown Synopsys component type: 0x%08x\n", reg); + return -ENODEV; + } + + /* + * Note we'll check the return value of the regmap IO accessors only + * at the probe stage. The rest of the code won't do this because + * basically we have MMIO-based regmap so non of the read/write methods + * can fail. + */ + dev->map = devm_regmap_init(dev->dev, NULL, dev, &map_cfg); + if (IS_ERR(dev->map)) { + dev_err(dev->dev, "Failed to init the registers map\n"); + return PTR_ERR(dev->map); + } + + return 0; +} + +static const u32 supported_speeds[] = { + I2C_MAX_HIGH_SPEED_MODE_FREQ, + I2C_MAX_FAST_MODE_PLUS_FREQ, + I2C_MAX_FAST_MODE_FREQ, + I2C_MAX_STANDARD_MODE_FREQ, +}; + +int i2c_dw_validate_speed(struct dw_i2c_dev *dev) +{ + struct i2c_timings *t = &dev->timings; + unsigned int i; + + /* + * Only standard mode at 100kHz, fast mode at 400kHz, + * fast mode plus at 1MHz and high speed mode at 3.4MHz are supported. + */ + for (i = 0; i < ARRAY_SIZE(supported_speeds); i++) { + if (t->bus_freq_hz == supported_speeds[i]) + return 0; + } + + dev_err(dev->dev, + "%d Hz is unsupported, only 100kHz, 400kHz, 1MHz and 3.4MHz are supported\n", + t->bus_freq_hz); + + return -EINVAL; +} +EXPORT_SYMBOL_GPL(i2c_dw_validate_speed); + +#ifdef CONFIG_ACPI + +#include <linux/dmi.h> + +/* + * The HCNT/LCNT information coming from ACPI should be the most accurate + * for given platform. However, some systems get it wrong. On such systems + * we get better results by calculating those based on the input clock. + */ +static const struct dmi_system_id i2c_dw_no_acpi_params[] = { + { + .ident = "Dell Inspiron 7348", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7348"), + }, + }, + {} +}; + +static void i2c_dw_acpi_params(struct device *device, char method[], + u16 *hcnt, u16 *lcnt, u32 *sda_hold) +{ + struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; + acpi_handle handle = ACPI_HANDLE(device); + union acpi_object *obj; + + if (dmi_check_system(i2c_dw_no_acpi_params)) + return; + + if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf))) + return; + + obj = (union acpi_object *)buf.pointer; + if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) { + const union acpi_object *objs = obj->package.elements; + + *hcnt = (u16)objs[0].integer.value; + *lcnt = (u16)objs[1].integer.value; + *sda_hold = (u32)objs[2].integer.value; + } + + kfree(buf.pointer); +} + +int i2c_dw_acpi_configure(struct device *device) +{ + struct dw_i2c_dev *dev = dev_get_drvdata(device); + struct i2c_timings *t = &dev->timings; + u32 ss_ht = 0, fp_ht = 0, hs_ht = 0, fs_ht = 0; + + /* + * Try to get SDA hold time and *CNT values from an ACPI method for + * selected speed modes. + */ + i2c_dw_acpi_params(device, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, &ss_ht); + i2c_dw_acpi_params(device, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt, &fs_ht); + i2c_dw_acpi_params(device, "FPCN", &dev->fp_hcnt, &dev->fp_lcnt, &fp_ht); + i2c_dw_acpi_params(device, "HSCN", &dev->hs_hcnt, &dev->hs_lcnt, &hs_ht); + + switch (t->bus_freq_hz) { + case I2C_MAX_STANDARD_MODE_FREQ: + dev->sda_hold_time = ss_ht; + break; + case I2C_MAX_FAST_MODE_PLUS_FREQ: + dev->sda_hold_time = fp_ht; + break; + case I2C_MAX_HIGH_SPEED_MODE_FREQ: + dev->sda_hold_time = hs_ht; + break; + case I2C_MAX_FAST_MODE_FREQ: + default: + dev->sda_hold_time = fs_ht; + break; + } + + return 0; +} +EXPORT_SYMBOL_GPL(i2c_dw_acpi_configure); + +static u32 i2c_dw_acpi_round_bus_speed(struct device *device) +{ + u32 acpi_speed; + int i; + + acpi_speed = i2c_acpi_find_bus_speed(device); + /* + * Some DSTDs use a non standard speed, round down to the lowest + * standard speed. + */ + for (i = 0; i < ARRAY_SIZE(supported_speeds); i++) { + if (acpi_speed >= supported_speeds[i]) + return supported_speeds[i]; + } + + return 0; +} + +#else /* CONFIG_ACPI */ + +static inline u32 i2c_dw_acpi_round_bus_speed(struct device *device) { return 0; } + +#endif /* CONFIG_ACPI */ + +void i2c_dw_adjust_bus_speed(struct dw_i2c_dev *dev) +{ + u32 acpi_speed = i2c_dw_acpi_round_bus_speed(dev->dev); + struct i2c_timings *t = &dev->timings; + + /* + * Find bus speed from the "clock-frequency" device property, ACPI + * or by using fast mode if neither is set. + */ + if (acpi_speed && t->bus_freq_hz) + t->bus_freq_hz = min(t->bus_freq_hz, acpi_speed); + else if (acpi_speed || t->bus_freq_hz) + t->bus_freq_hz = max(t->bus_freq_hz, acpi_speed); + else + t->bus_freq_hz = I2C_MAX_FAST_MODE_FREQ; +} +EXPORT_SYMBOL_GPL(i2c_dw_adjust_bus_speed); + +u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset) +{ + /* + * DesignWare I2C core doesn't seem to have solid strategy to meet + * the tHD;STA timing spec. Configuring _HCNT based on tHIGH spec + * will result in violation of the tHD;STA spec. + */ + if (cond) + /* + * Conditional expression: + * + * IC_[FS]S_SCL_HCNT + (1+4+3) >= IC_CLK * tHIGH + * + * This is based on the DW manuals, and represents an ideal + * configuration. The resulting I2C bus speed will be + * faster than any of the others. + * + * If your hardware is free from tHD;STA issue, try this one. + */ + return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * tSYMBOL, MICRO) - + 8 + offset; + else + /* + * Conditional expression: + * + * IC_[FS]S_SCL_HCNT + 3 >= IC_CLK * (tHD;STA + tf) + * + * This is just experimental rule; the tHD;STA period turned + * out to be proportinal to (_HCNT + 3). With this setting, + * we could meet both tHIGH and tHD;STA timing specs. + * + * If unsure, you'd better to take this alternative. + * + * The reason why we need to take into account "tf" here, + * is the same as described in i2c_dw_scl_lcnt(). + */ + return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * (tSYMBOL + tf), MICRO) - + 3 + offset; +} + +u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset) +{ + /* + * Conditional expression: + * + * IC_[FS]S_SCL_LCNT + 1 >= IC_CLK * (tLOW + tf) + * + * DW I2C core starts counting the SCL CNTs for the LOW period + * of the SCL clock (tLOW) as soon as it pulls the SCL line. + * In order to meet the tLOW timing spec, we need to take into + * account the fall time of SCL signal (tf). Default tf value + * should be 0.3 us, for safety. + */ + return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * (tLOW + tf), MICRO) - + 1 + offset; +} + +int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev) +{ + unsigned int reg; + int ret; + + ret = i2c_dw_acquire_lock(dev); + if (ret) + return ret; + + /* Configure SDA Hold Time if required */ + ret = regmap_read(dev->map, DW_IC_COMP_VERSION, ®); + if (ret) + goto err_release_lock; + + if (reg >= DW_IC_SDA_HOLD_MIN_VERS) { + if (!dev->sda_hold_time) { + /* Keep previous hold time setting if no one set it */ + ret = regmap_read(dev->map, DW_IC_SDA_HOLD, + &dev->sda_hold_time); + if (ret) + goto err_release_lock; + } + + /* + * Workaround for avoiding TX arbitration lost in case I2C + * slave pulls SDA down "too quickly" after falling edge of + * SCL by enabling non-zero SDA RX hold. Specification says it + * extends incoming SDA low to high transition while SCL is + * high but it appears to help also above issue. + */ + if (!(dev->sda_hold_time & DW_IC_SDA_HOLD_RX_MASK)) + dev->sda_hold_time |= 1 << DW_IC_SDA_HOLD_RX_SHIFT; + + dev_dbg(dev->dev, "SDA Hold Time TX:RX = %d:%d\n", + dev->sda_hold_time & ~(u32)DW_IC_SDA_HOLD_RX_MASK, + dev->sda_hold_time >> DW_IC_SDA_HOLD_RX_SHIFT); + } else if (dev->set_sda_hold_time) { + dev->set_sda_hold_time(dev); + } else if (dev->sda_hold_time) { + dev_warn(dev->dev, + "Hardware too old to adjust SDA hold time.\n"); + dev->sda_hold_time = 0; + } + +err_release_lock: + i2c_dw_release_lock(dev); + + return ret; +} + +void __i2c_dw_disable(struct dw_i2c_dev *dev) +{ + unsigned int raw_intr_stats; + unsigned int enable; + int timeout = 100; + bool abort_needed; + unsigned int status; + int ret; + + regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &raw_intr_stats); + regmap_read(dev->map, DW_IC_ENABLE, &enable); + + abort_needed = raw_intr_stats & DW_IC_INTR_MST_ON_HOLD; + if (abort_needed) { + regmap_write(dev->map, DW_IC_ENABLE, enable | DW_IC_ENABLE_ABORT); + ret = regmap_read_poll_timeout(dev->map, DW_IC_ENABLE, enable, + !(enable & DW_IC_ENABLE_ABORT), 10, + 100); + if (ret) + dev_err(dev->dev, "timeout while trying to abort current transfer\n"); + } + + do { + __i2c_dw_disable_nowait(dev); + /* + * The enable status register may be unimplemented, but + * in that case this test reads zero and exits the loop. + */ + regmap_read(dev->map, DW_IC_ENABLE_STATUS, &status); + if ((status & 1) == 0) + return; + + /* + * Wait 10 times the signaling period of the highest I2C + * transfer supported by the driver (for 400KHz this is + * 25us) as described in the DesignWare I2C databook. + */ + usleep_range(25, 250); + } while (timeout--); + + dev_warn(dev->dev, "timeout in disabling adapter\n"); +} + +u32 i2c_dw_clk_rate(struct dw_i2c_dev *dev) +{ + /* + * Clock is not necessary if we got LCNT/HCNT values directly from + * the platform code. + */ + if (WARN_ON_ONCE(!dev->get_clk_rate_khz)) + return 0; + return dev->get_clk_rate_khz(dev); +} + +int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare) +{ + int ret; + + if (prepare) { + /* Optional interface clock */ + ret = clk_prepare_enable(dev->pclk); + if (ret) + return ret; + + ret = clk_prepare_enable(dev->clk); + if (ret) + clk_disable_unprepare(dev->pclk); + + return ret; + } + + clk_disable_unprepare(dev->clk); + clk_disable_unprepare(dev->pclk); + + return 0; +} +EXPORT_SYMBOL_GPL(i2c_dw_prepare_clk); + +int i2c_dw_acquire_lock(struct dw_i2c_dev *dev) +{ + int ret; + + if (!dev->acquire_lock) + return 0; + + ret = dev->acquire_lock(); + if (!ret) + return 0; + + dev_err(dev->dev, "couldn't acquire bus ownership\n"); + + return ret; +} + +void i2c_dw_release_lock(struct dw_i2c_dev *dev) +{ + if (dev->release_lock) + dev->release_lock(); +} + +/* + * Waiting for bus not busy + */ +int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev) +{ + unsigned int status; + int ret; + + ret = regmap_read_poll_timeout(dev->map, DW_IC_STATUS, status, + !(status & DW_IC_STATUS_ACTIVITY), + 1100, 20000); + if (ret) { + dev_warn(dev->dev, "timeout waiting for bus ready\n"); + + i2c_recover_bus(&dev->adapter); + + regmap_read(dev->map, DW_IC_STATUS, &status); + if (!(status & DW_IC_STATUS_ACTIVITY)) + ret = 0; + } + + return ret; +} + +int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev) +{ + unsigned long abort_source = dev->abort_source; + int i; + + if (abort_source & DW_IC_TX_ABRT_NOACK) { + for_each_set_bit(i, &abort_source, ARRAY_SIZE(abort_sources)) + dev_dbg(dev->dev, + "%s: %s\n", __func__, abort_sources[i]); + return -EREMOTEIO; + } + + for_each_set_bit(i, &abort_source, ARRAY_SIZE(abort_sources)) + dev_err(dev->dev, "%s: %s\n", __func__, abort_sources[i]); + + if (abort_source & DW_IC_TX_ARB_LOST) + return -EAGAIN; + else if (abort_source & DW_IC_TX_ABRT_GCALL_READ) + return -EINVAL; /* wrong msgs[] data */ + else + return -EIO; +} + +int i2c_dw_set_fifo_size(struct dw_i2c_dev *dev) +{ + u32 tx_fifo_depth, rx_fifo_depth; + unsigned int param; + int ret; + + /* DW_IC_COMP_PARAM_1 not implement for IP issue */ + if ((dev->flags & MODEL_MASK) == MODEL_WANGXUN_SP) { + dev->tx_fifo_depth = TXGBE_TX_FIFO_DEPTH; + dev->rx_fifo_depth = TXGBE_RX_FIFO_DEPTH; + + return 0; + } + + /* + * Try to detect the FIFO depth if not set by interface driver, + * the depth could be from 2 to 256 from HW spec. + */ + ret = i2c_dw_acquire_lock(dev); + if (ret) + return ret; + + ret = regmap_read(dev->map, DW_IC_COMP_PARAM_1, ¶m); + i2c_dw_release_lock(dev); + if (ret) + return ret; + + tx_fifo_depth = ((param >> 16) & 0xff) + 1; + rx_fifo_depth = ((param >> 8) & 0xff) + 1; + if (!dev->tx_fifo_depth) { + dev->tx_fifo_depth = tx_fifo_depth; + dev->rx_fifo_depth = rx_fifo_depth; + } else if (tx_fifo_depth >= 2) { + dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth, + tx_fifo_depth); + dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth, + rx_fifo_depth); + } + + return 0; +} + +u32 i2c_dw_func(struct i2c_adapter *adap) +{ + struct dw_i2c_dev *dev = i2c_get_adapdata(adap); + + return dev->functionality; +} + +void i2c_dw_disable(struct dw_i2c_dev *dev) +{ + unsigned int dummy; + int ret; + + ret = i2c_dw_acquire_lock(dev); + if (ret) + return; + + /* Disable controller */ + __i2c_dw_disable(dev); + + /* Disable all interrupts */ + regmap_write(dev->map, DW_IC_INTR_MASK, 0); + regmap_read(dev->map, DW_IC_CLR_INTR, &dummy); + + i2c_dw_release_lock(dev); +} + +MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter core"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h new file mode 100644 index 000000000..a7f6f3eaf --- /dev/null +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -0,0 +1,403 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Synopsys DesignWare I2C adapter driver. + * + * Based on the TI DAVINCI I2C adapter driver. + * + * Copyright (C) 2006 Texas Instruments. + * Copyright (C) 2007 MontaVista Software Inc. + * Copyright (C) 2009 Provigent Ltd. + */ + +#include <linux/bits.h> +#include <linux/compiler_types.h> +#include <linux/completion.h> +#include <linux/dev_printk.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/regmap.h> +#include <linux/types.h> + +#define DW_IC_DEFAULT_FUNCTIONALITY (I2C_FUNC_I2C | \ + I2C_FUNC_SMBUS_BYTE | \ + I2C_FUNC_SMBUS_BYTE_DATA | \ + I2C_FUNC_SMBUS_WORD_DATA | \ + I2C_FUNC_SMBUS_BLOCK_DATA | \ + I2C_FUNC_SMBUS_I2C_BLOCK) + +#define DW_IC_CON_MASTER BIT(0) +#define DW_IC_CON_SPEED_STD (1 << 1) +#define DW_IC_CON_SPEED_FAST (2 << 1) +#define DW_IC_CON_SPEED_HIGH (3 << 1) +#define DW_IC_CON_SPEED_MASK GENMASK(2, 1) +#define DW_IC_CON_10BITADDR_SLAVE BIT(3) +#define DW_IC_CON_10BITADDR_MASTER BIT(4) +#define DW_IC_CON_RESTART_EN BIT(5) +#define DW_IC_CON_SLAVE_DISABLE BIT(6) +#define DW_IC_CON_STOP_DET_IFADDRESSED BIT(7) +#define DW_IC_CON_TX_EMPTY_CTRL BIT(8) +#define DW_IC_CON_RX_FIFO_FULL_HLD_CTRL BIT(9) +#define DW_IC_CON_BUS_CLEAR_CTRL BIT(11) + +#define DW_IC_DATA_CMD_DAT GENMASK(7, 0) +#define DW_IC_DATA_CMD_FIRST_DATA_BYTE BIT(11) + +/* + * Registers offset + */ +#define DW_IC_CON 0x00 +#define DW_IC_TAR 0x04 +#define DW_IC_SAR 0x08 +#define DW_IC_DATA_CMD 0x10 +#define DW_IC_SS_SCL_HCNT 0x14 +#define DW_IC_SS_SCL_LCNT 0x18 +#define DW_IC_FS_SCL_HCNT 0x1c +#define DW_IC_FS_SCL_LCNT 0x20 +#define DW_IC_HS_SCL_HCNT 0x24 +#define DW_IC_HS_SCL_LCNT 0x28 +#define DW_IC_INTR_STAT 0x2c +#define DW_IC_INTR_MASK 0x30 +#define DW_IC_RAW_INTR_STAT 0x34 +#define DW_IC_RX_TL 0x38 +#define DW_IC_TX_TL 0x3c +#define DW_IC_CLR_INTR 0x40 +#define DW_IC_CLR_RX_UNDER 0x44 +#define DW_IC_CLR_RX_OVER 0x48 +#define DW_IC_CLR_TX_OVER 0x4c +#define DW_IC_CLR_RD_REQ 0x50 +#define DW_IC_CLR_TX_ABRT 0x54 +#define DW_IC_CLR_RX_DONE 0x58 +#define DW_IC_CLR_ACTIVITY 0x5c +#define DW_IC_CLR_STOP_DET 0x60 +#define DW_IC_CLR_START_DET 0x64 +#define DW_IC_CLR_GEN_CALL 0x68 +#define DW_IC_ENABLE 0x6c +#define DW_IC_STATUS 0x70 +#define DW_IC_TXFLR 0x74 +#define DW_IC_RXFLR 0x78 +#define DW_IC_SDA_HOLD 0x7c +#define DW_IC_TX_ABRT_SOURCE 0x80 +#define DW_IC_ENABLE_STATUS 0x9c +#define DW_IC_CLR_RESTART_DET 0xa8 +#define DW_IC_COMP_PARAM_1 0xf4 +#define DW_IC_COMP_VERSION 0xf8 +#define DW_IC_SDA_HOLD_MIN_VERS 0x3131312A /* "111*" == v1.11* */ +#define DW_IC_COMP_TYPE 0xfc +#define DW_IC_COMP_TYPE_VALUE 0x44570140 /* "DW" + 0x0140 */ + +#define DW_IC_INTR_RX_UNDER BIT(0) +#define DW_IC_INTR_RX_OVER BIT(1) +#define DW_IC_INTR_RX_FULL BIT(2) +#define DW_IC_INTR_TX_OVER BIT(3) +#define DW_IC_INTR_TX_EMPTY BIT(4) +#define DW_IC_INTR_RD_REQ BIT(5) +#define DW_IC_INTR_TX_ABRT BIT(6) +#define DW_IC_INTR_RX_DONE BIT(7) +#define DW_IC_INTR_ACTIVITY BIT(8) +#define DW_IC_INTR_STOP_DET BIT(9) +#define DW_IC_INTR_START_DET BIT(10) +#define DW_IC_INTR_GEN_CALL BIT(11) +#define DW_IC_INTR_RESTART_DET BIT(12) +#define DW_IC_INTR_MST_ON_HOLD BIT(13) + +#define DW_IC_INTR_DEFAULT_MASK (DW_IC_INTR_RX_FULL | \ + DW_IC_INTR_TX_ABRT | \ + DW_IC_INTR_STOP_DET) +#define DW_IC_INTR_MASTER_MASK (DW_IC_INTR_DEFAULT_MASK | \ + DW_IC_INTR_TX_EMPTY) +#define DW_IC_INTR_SLAVE_MASK (DW_IC_INTR_DEFAULT_MASK | \ + DW_IC_INTR_RX_UNDER | \ + DW_IC_INTR_RD_REQ) + +#define DW_IC_ENABLE_ABORT BIT(1) + +#define DW_IC_STATUS_ACTIVITY BIT(0) +#define DW_IC_STATUS_TFE BIT(2) +#define DW_IC_STATUS_RFNE BIT(3) +#define DW_IC_STATUS_MASTER_ACTIVITY BIT(5) +#define DW_IC_STATUS_SLAVE_ACTIVITY BIT(6) + +#define DW_IC_SDA_HOLD_RX_SHIFT 16 +#define DW_IC_SDA_HOLD_RX_MASK GENMASK(23, 16) + +#define DW_IC_ERR_TX_ABRT 0x1 + +#define DW_IC_TAR_10BITADDR_MASTER BIT(12) + +#define DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH (BIT(2) | BIT(3)) +#define DW_IC_COMP_PARAM_1_SPEED_MODE_MASK GENMASK(3, 2) + +/* + * Sofware status flags + */ +#define STATUS_ACTIVE BIT(0) +#define STATUS_WRITE_IN_PROGRESS BIT(1) +#define STATUS_READ_IN_PROGRESS BIT(2) +#define STATUS_MASK GENMASK(2, 0) + +/* + * operation modes + */ +#define DW_IC_MASTER 0 +#define DW_IC_SLAVE 1 + +/* + * Hardware abort codes from the DW_IC_TX_ABRT_SOURCE register + * + * Only expected abort codes are listed here + * refer to the datasheet for the full list + */ +#define ABRT_7B_ADDR_NOACK 0 +#define ABRT_10ADDR1_NOACK 1 +#define ABRT_10ADDR2_NOACK 2 +#define ABRT_TXDATA_NOACK 3 +#define ABRT_GCALL_NOACK 4 +#define ABRT_GCALL_READ 5 +#define ABRT_SBYTE_ACKDET 7 +#define ABRT_SBYTE_NORSTRT 9 +#define ABRT_10B_RD_NORSTRT 10 +#define ABRT_MASTER_DIS 11 +#define ARB_LOST 12 +#define ABRT_SLAVE_FLUSH_TXFIFO 13 +#define ABRT_SLAVE_ARBLOST 14 +#define ABRT_SLAVE_RD_INTX 15 + +#define DW_IC_TX_ABRT_7B_ADDR_NOACK BIT(ABRT_7B_ADDR_NOACK) +#define DW_IC_TX_ABRT_10ADDR1_NOACK BIT(ABRT_10ADDR1_NOACK) +#define DW_IC_TX_ABRT_10ADDR2_NOACK BIT(ABRT_10ADDR2_NOACK) +#define DW_IC_TX_ABRT_TXDATA_NOACK BIT(ABRT_TXDATA_NOACK) +#define DW_IC_TX_ABRT_GCALL_NOACK BIT(ABRT_GCALL_NOACK) +#define DW_IC_TX_ABRT_GCALL_READ BIT(ABRT_GCALL_READ) +#define DW_IC_TX_ABRT_SBYTE_ACKDET BIT(ABRT_SBYTE_ACKDET) +#define DW_IC_TX_ABRT_SBYTE_NORSTRT BIT(ABRT_SBYTE_NORSTRT) +#define DW_IC_TX_ABRT_10B_RD_NORSTRT BIT(ABRT_10B_RD_NORSTRT) +#define DW_IC_TX_ABRT_MASTER_DIS BIT(ABRT_MASTER_DIS) +#define DW_IC_TX_ARB_LOST BIT(ARB_LOST) +#define DW_IC_RX_ABRT_SLAVE_RD_INTX BIT(ABRT_SLAVE_RD_INTX) +#define DW_IC_RX_ABRT_SLAVE_ARBLOST BIT(ABRT_SLAVE_ARBLOST) +#define DW_IC_RX_ABRT_SLAVE_FLUSH_TXFIFO BIT(ABRT_SLAVE_FLUSH_TXFIFO) + +#define DW_IC_TX_ABRT_NOACK (DW_IC_TX_ABRT_7B_ADDR_NOACK | \ + DW_IC_TX_ABRT_10ADDR1_NOACK | \ + DW_IC_TX_ABRT_10ADDR2_NOACK | \ + DW_IC_TX_ABRT_TXDATA_NOACK | \ + DW_IC_TX_ABRT_GCALL_NOACK) + +struct clk; +struct device; +struct reset_control; + +/** + * struct dw_i2c_dev - private i2c-designware data + * @dev: driver model device node + * @map: IO registers map + * @sysmap: System controller registers map + * @base: IO registers pointer + * @ext: Extended IO registers pointer + * @cmd_complete: tx completion indicator + * @clk: input reference clock + * @pclk: clock required to access the registers + * @rst: optional reset for the controller + * @slave: represent an I2C slave device + * @get_clk_rate_khz: callback to retrieve IP specific bus speed + * @cmd_err: run time hadware error code + * @msgs: points to an array of messages currently being transferred + * @msgs_num: the number of elements in msgs + * @msg_write_idx: the element index of the current tx message in the msgs array + * @tx_buf_len: the length of the current tx buffer + * @tx_buf: the current tx buffer + * @msg_read_idx: the element index of the current rx message in the msgs array + * @rx_buf_len: the length of the current rx buffer + * @rx_buf: the current rx buffer + * @msg_err: error status of the current transfer + * @status: i2c master status, one of STATUS_* + * @abort_source: copy of the TX_ABRT_SOURCE register + * @irq: interrupt number for the i2c master + * @flags: platform specific flags like type of IO accessors or model + * @adapter: i2c subsystem adapter node + * @functionality: I2C_FUNC_* ORed bits to reflect what controller does support + * @master_cfg: configuration for the master device + * @slave_cfg: configuration for the slave device + * @tx_fifo_depth: depth of the hardware tx fifo + * @rx_fifo_depth: depth of the hardware rx fifo + * @rx_outstanding: current master-rx elements in tx fifo + * @timings: bus clock frequency, SDA hold and other timings + * @sda_hold_time: SDA hold value + * @ss_hcnt: standard speed HCNT value + * @ss_lcnt: standard speed LCNT value + * @fs_hcnt: fast speed HCNT value + * @fs_lcnt: fast speed LCNT value + * @fp_hcnt: fast plus HCNT value + * @fp_lcnt: fast plus LCNT value + * @hs_hcnt: high speed HCNT value + * @hs_lcnt: high speed LCNT value + * @acquire_lock: function to acquire a hardware lock on the bus + * @release_lock: function to release a hardware lock on the bus + * @semaphore_idx: Index of table with semaphore type attached to the bus. It's + * -1 if there is no semaphore. + * @shared_with_punit: true if this bus is shared with the SoCs PUNIT + * @disable: function to disable the controller + * @init: function to initialize the I2C hardware + * @set_sda_hold_time: callback to retrieve IP specific SDA hold timing + * @mode: operation mode - DW_IC_MASTER or DW_IC_SLAVE + * @rinfo: I²C GPIO recovery information + * + * HCNT and LCNT parameters can be used if the platform knows more accurate + * values than the one computed based only on the input clock frequency. + * Leave them to be %0 if not used. + */ +struct dw_i2c_dev { + struct device *dev; + struct regmap *map; + struct regmap *sysmap; + void __iomem *base; + void __iomem *ext; + struct completion cmd_complete; + struct clk *clk; + struct clk *pclk; + struct reset_control *rst; + struct i2c_client *slave; + u32 (*get_clk_rate_khz) (struct dw_i2c_dev *dev); + int cmd_err; + struct i2c_msg *msgs; + int msgs_num; + int msg_write_idx; + u32 tx_buf_len; + u8 *tx_buf; + int msg_read_idx; + u32 rx_buf_len; + u8 *rx_buf; + int msg_err; + unsigned int status; + unsigned int abort_source; + int irq; + u32 flags; + struct i2c_adapter adapter; + u32 functionality; + u32 master_cfg; + u32 slave_cfg; + unsigned int tx_fifo_depth; + unsigned int rx_fifo_depth; + int rx_outstanding; + struct i2c_timings timings; + u32 sda_hold_time; + u16 ss_hcnt; + u16 ss_lcnt; + u16 fs_hcnt; + u16 fs_lcnt; + u16 fp_hcnt; + u16 fp_lcnt; + u16 hs_hcnt; + u16 hs_lcnt; + int (*acquire_lock)(void); + void (*release_lock)(void); + int semaphore_idx; + bool shared_with_punit; + void (*disable)(struct dw_i2c_dev *dev); + int (*init)(struct dw_i2c_dev *dev); + int (*set_sda_hold_time)(struct dw_i2c_dev *dev); + int mode; + struct i2c_bus_recovery_info rinfo; +}; + +#define ACCESS_INTR_MASK BIT(0) +#define ACCESS_NO_IRQ_SUSPEND BIT(1) +#define ARBITRATION_SEMAPHORE BIT(2) + +#define MODEL_MSCC_OCELOT BIT(8) +#define MODEL_BAIKAL_BT1 BIT(9) +#define MODEL_AMD_NAVI_GPU BIT(10) +#define MODEL_WANGXUN_SP BIT(11) +#define MODEL_MASK GENMASK(11, 8) + +/* + * Enable UCSI interrupt by writing 0xd at register + * offset 0x474 specified in hardware specification. + */ +#define AMD_UCSI_INTR_REG 0x474 +#define AMD_UCSI_INTR_EN 0xd + +#define TXGBE_TX_FIFO_DEPTH 4 +#define TXGBE_RX_FIFO_DEPTH 0 + +struct i2c_dw_semaphore_callbacks { + int (*probe)(struct dw_i2c_dev *dev); + void (*remove)(struct dw_i2c_dev *dev); +}; + +int i2c_dw_init_regmap(struct dw_i2c_dev *dev); +u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset); +u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset); +int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev); +u32 i2c_dw_clk_rate(struct dw_i2c_dev *dev); +int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare); +int i2c_dw_acquire_lock(struct dw_i2c_dev *dev); +void i2c_dw_release_lock(struct dw_i2c_dev *dev); +int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev); +int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev); +int i2c_dw_set_fifo_size(struct dw_i2c_dev *dev); +u32 i2c_dw_func(struct i2c_adapter *adap); +void i2c_dw_disable(struct dw_i2c_dev *dev); + +static inline void __i2c_dw_enable(struct dw_i2c_dev *dev) +{ + dev->status |= STATUS_ACTIVE; + regmap_write(dev->map, DW_IC_ENABLE, 1); +} + +static inline void __i2c_dw_disable_nowait(struct dw_i2c_dev *dev) +{ + regmap_write(dev->map, DW_IC_ENABLE, 0); + dev->status &= ~STATUS_ACTIVE; +} + +void __i2c_dw_disable(struct dw_i2c_dev *dev); + +extern void i2c_dw_configure_master(struct dw_i2c_dev *dev); +extern int i2c_dw_probe_master(struct dw_i2c_dev *dev); + +#if IS_ENABLED(CONFIG_I2C_DESIGNWARE_SLAVE) +extern void i2c_dw_configure_slave(struct dw_i2c_dev *dev); +extern int i2c_dw_probe_slave(struct dw_i2c_dev *dev); +#else +static inline void i2c_dw_configure_slave(struct dw_i2c_dev *dev) { } +static inline int i2c_dw_probe_slave(struct dw_i2c_dev *dev) { return -EINVAL; } +#endif + +static inline int i2c_dw_probe(struct dw_i2c_dev *dev) +{ + switch (dev->mode) { + case DW_IC_SLAVE: + return i2c_dw_probe_slave(dev); + case DW_IC_MASTER: + return i2c_dw_probe_master(dev); + default: + dev_err(dev->dev, "Wrong operation mode: %d\n", dev->mode); + return -EINVAL; + } +} + +static inline void i2c_dw_configure(struct dw_i2c_dev *dev) +{ + if (i2c_detect_slave_mode(dev->dev)) + i2c_dw_configure_slave(dev); + else + i2c_dw_configure_master(dev); +} + +#if IS_ENABLED(CONFIG_I2C_DESIGNWARE_BAYTRAIL) +int i2c_dw_baytrail_probe_lock_support(struct dw_i2c_dev *dev); +#endif + +#if IS_ENABLED(CONFIG_I2C_DESIGNWARE_AMDPSP) +int i2c_dw_amdpsp_probe_lock_support(struct dw_i2c_dev *dev); +#endif + +int i2c_dw_validate_speed(struct dw_i2c_dev *dev); +void i2c_dw_adjust_bus_speed(struct dw_i2c_dev *dev); + +#if IS_ENABLED(CONFIG_ACPI) +int i2c_dw_acpi_configure(struct device *device); +#else +static inline int i2c_dw_acpi_configure(struct device *device) { return -ENODEV; } +#endif diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c new file mode 100644 index 000000000..85dbd0eb5 --- /dev/null +++ b/drivers/i2c/busses/i2c-designware-master.c @@ -0,0 +1,1081 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Synopsys DesignWare I2C adapter driver (master only). + * + * Based on the TI DAVINCI I2C adapter driver. + * + * Copyright (C) 2006 Texas Instruments. + * Copyright (C) 2007 MontaVista Software Inc. + * Copyright (C) 2009 Provigent Ltd. + */ +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/export.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/pinctrl/consumer.h> +#include <linux/pm_runtime.h> +#include <linux/regmap.h> +#include <linux/reset.h> + +#include "i2c-designware-core.h" + +#define AMD_TIMEOUT_MIN_US 25 +#define AMD_TIMEOUT_MAX_US 250 +#define AMD_MASTERCFG_MASK GENMASK(15, 0) + +static void i2c_dw_configure_fifo_master(struct dw_i2c_dev *dev) +{ + /* Configure Tx/Rx FIFO threshold levels */ + regmap_write(dev->map, DW_IC_TX_TL, dev->tx_fifo_depth / 2); + regmap_write(dev->map, DW_IC_RX_TL, 0); + + /* Configure the I2C master */ + regmap_write(dev->map, DW_IC_CON, dev->master_cfg); +} + +static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev) +{ + unsigned int comp_param1; + u32 sda_falling_time, scl_falling_time; + struct i2c_timings *t = &dev->timings; + const char *fp_str = ""; + u32 ic_clk; + int ret; + + ret = i2c_dw_acquire_lock(dev); + if (ret) + return ret; + + ret = regmap_read(dev->map, DW_IC_COMP_PARAM_1, &comp_param1); + i2c_dw_release_lock(dev); + if (ret) + return ret; + + /* Set standard and fast speed dividers for high/low periods */ + sda_falling_time = t->sda_fall_ns ?: 300; /* ns */ + scl_falling_time = t->scl_fall_ns ?: 300; /* ns */ + + /* Calculate SCL timing parameters for standard mode if not set */ + if (!dev->ss_hcnt || !dev->ss_lcnt) { + ic_clk = i2c_dw_clk_rate(dev); + dev->ss_hcnt = + i2c_dw_scl_hcnt(ic_clk, + 4000, /* tHD;STA = tHIGH = 4.0 us */ + sda_falling_time, + 0, /* 0: DW default, 1: Ideal */ + 0); /* No offset */ + dev->ss_lcnt = + i2c_dw_scl_lcnt(ic_clk, + 4700, /* tLOW = 4.7 us */ + scl_falling_time, + 0); /* No offset */ + } + dev_dbg(dev->dev, "Standard Mode HCNT:LCNT = %d:%d\n", + dev->ss_hcnt, dev->ss_lcnt); + + /* + * Set SCL timing parameters for fast mode or fast mode plus. Only + * difference is the timing parameter values since the registers are + * the same. + */ + if (t->bus_freq_hz == I2C_MAX_FAST_MODE_PLUS_FREQ) { + /* + * Check are Fast Mode Plus parameters available. Calculate + * SCL timing parameters for Fast Mode Plus if not set. + */ + if (dev->fp_hcnt && dev->fp_lcnt) { + dev->fs_hcnt = dev->fp_hcnt; + dev->fs_lcnt = dev->fp_lcnt; + } else { + ic_clk = i2c_dw_clk_rate(dev); + dev->fs_hcnt = + i2c_dw_scl_hcnt(ic_clk, + 260, /* tHIGH = 260 ns */ + sda_falling_time, + 0, /* DW default */ + 0); /* No offset */ + dev->fs_lcnt = + i2c_dw_scl_lcnt(ic_clk, + 500, /* tLOW = 500 ns */ + scl_falling_time, + 0); /* No offset */ + } + fp_str = " Plus"; + } + /* + * Calculate SCL timing parameters for fast mode if not set. They are + * needed also in high speed mode. + */ + if (!dev->fs_hcnt || !dev->fs_lcnt) { + ic_clk = i2c_dw_clk_rate(dev); + dev->fs_hcnt = + i2c_dw_scl_hcnt(ic_clk, + 600, /* tHD;STA = tHIGH = 0.6 us */ + sda_falling_time, + 0, /* 0: DW default, 1: Ideal */ + 0); /* No offset */ + dev->fs_lcnt = + i2c_dw_scl_lcnt(ic_clk, + 1300, /* tLOW = 1.3 us */ + scl_falling_time, + 0); /* No offset */ + } + dev_dbg(dev->dev, "Fast Mode%s HCNT:LCNT = %d:%d\n", + fp_str, dev->fs_hcnt, dev->fs_lcnt); + + /* Check is high speed possible and fall back to fast mode if not */ + if ((dev->master_cfg & DW_IC_CON_SPEED_MASK) == + DW_IC_CON_SPEED_HIGH) { + if ((comp_param1 & DW_IC_COMP_PARAM_1_SPEED_MODE_MASK) + != DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH) { + dev_err(dev->dev, "High Speed not supported!\n"); + t->bus_freq_hz = I2C_MAX_FAST_MODE_FREQ; + dev->master_cfg &= ~DW_IC_CON_SPEED_MASK; + dev->master_cfg |= DW_IC_CON_SPEED_FAST; + dev->hs_hcnt = 0; + dev->hs_lcnt = 0; + } else if (!dev->hs_hcnt || !dev->hs_lcnt) { + ic_clk = i2c_dw_clk_rate(dev); + dev->hs_hcnt = + i2c_dw_scl_hcnt(ic_clk, + 160, /* tHIGH = 160 ns */ + sda_falling_time, + 0, /* DW default */ + 0); /* No offset */ + dev->hs_lcnt = + i2c_dw_scl_lcnt(ic_clk, + 320, /* tLOW = 320 ns */ + scl_falling_time, + 0); /* No offset */ + } + dev_dbg(dev->dev, "High Speed Mode HCNT:LCNT = %d:%d\n", + dev->hs_hcnt, dev->hs_lcnt); + } + + ret = i2c_dw_set_sda_hold(dev); + if (ret) + return ret; + + dev_dbg(dev->dev, "Bus speed: %s\n", i2c_freq_mode_string(t->bus_freq_hz)); + return 0; +} + +/** + * i2c_dw_init_master() - Initialize the designware I2C master hardware + * @dev: device private data + * + * This functions configures and enables the I2C master. + * This function is called during I2C init function, and in case of timeout at + * run time. + */ +static int i2c_dw_init_master(struct dw_i2c_dev *dev) +{ + int ret; + + ret = i2c_dw_acquire_lock(dev); + if (ret) + return ret; + + /* Disable the adapter */ + __i2c_dw_disable(dev); + + /* Write standard speed timing parameters */ + regmap_write(dev->map, DW_IC_SS_SCL_HCNT, dev->ss_hcnt); + regmap_write(dev->map, DW_IC_SS_SCL_LCNT, dev->ss_lcnt); + + /* Write fast mode/fast mode plus timing parameters */ + regmap_write(dev->map, DW_IC_FS_SCL_HCNT, dev->fs_hcnt); + regmap_write(dev->map, DW_IC_FS_SCL_LCNT, dev->fs_lcnt); + + /* Write high speed timing parameters if supported */ + if (dev->hs_hcnt && dev->hs_lcnt) { + regmap_write(dev->map, DW_IC_HS_SCL_HCNT, dev->hs_hcnt); + regmap_write(dev->map, DW_IC_HS_SCL_LCNT, dev->hs_lcnt); + } + + /* Write SDA hold time if supported */ + if (dev->sda_hold_time) + regmap_write(dev->map, DW_IC_SDA_HOLD, dev->sda_hold_time); + + i2c_dw_configure_fifo_master(dev); + i2c_dw_release_lock(dev); + + return 0; +} + +static void i2c_dw_xfer_init(struct dw_i2c_dev *dev) +{ + struct i2c_msg *msgs = dev->msgs; + u32 ic_con = 0, ic_tar = 0; + unsigned int dummy; + + /* Disable the adapter */ + __i2c_dw_disable(dev); + + /* If the slave address is ten bit address, enable 10BITADDR */ + if (msgs[dev->msg_write_idx].flags & I2C_M_TEN) { + ic_con = DW_IC_CON_10BITADDR_MASTER; + /* + * If I2C_DYNAMIC_TAR_UPDATE is set, the 10-bit addressing + * mode has to be enabled via bit 12 of IC_TAR register. + * We set it always as I2C_DYNAMIC_TAR_UPDATE can't be + * detected from registers. + */ + ic_tar = DW_IC_TAR_10BITADDR_MASTER; + } + + regmap_update_bits(dev->map, DW_IC_CON, DW_IC_CON_10BITADDR_MASTER, + ic_con); + + /* + * Set the slave (target) address and enable 10-bit addressing mode + * if applicable. + */ + regmap_write(dev->map, DW_IC_TAR, + msgs[dev->msg_write_idx].addr | ic_tar); + + /* Enforce disabled interrupts (due to HW issues) */ + regmap_write(dev->map, DW_IC_INTR_MASK, 0); + + /* Enable the adapter */ + __i2c_dw_enable(dev); + + /* Dummy read to avoid the register getting stuck on Bay Trail */ + regmap_read(dev->map, DW_IC_ENABLE_STATUS, &dummy); + + /* Clear and enable interrupts */ + regmap_read(dev->map, DW_IC_CLR_INTR, &dummy); + regmap_write(dev->map, DW_IC_INTR_MASK, DW_IC_INTR_MASTER_MASK); +} + +static int i2c_dw_check_stopbit(struct dw_i2c_dev *dev) +{ + u32 val; + int ret; + + ret = regmap_read_poll_timeout(dev->map, DW_IC_INTR_STAT, val, + !(val & DW_IC_INTR_STOP_DET), + 1100, 20000); + if (ret) + dev_err(dev->dev, "i2c timeout error %d\n", ret); + + return ret; +} + +static int i2c_dw_status(struct dw_i2c_dev *dev) +{ + int status; + + status = i2c_dw_wait_bus_not_busy(dev); + if (status) + return status; + + return i2c_dw_check_stopbit(dev); +} + +/* + * Initiate and continue master read/write transaction with polling + * based transfer routine afterward write messages into the Tx buffer. + */ +static int amd_i2c_dw_xfer_quirk(struct i2c_adapter *adap, struct i2c_msg *msgs, int num_msgs) +{ + struct dw_i2c_dev *dev = i2c_get_adapdata(adap); + int msg_wrt_idx, msg_itr_lmt, buf_len, data_idx; + int cmd = 0, status; + u8 *tx_buf; + unsigned int val; + + /* + * In order to enable the interrupt for UCSI i.e. AMD NAVI GPU card, + * it is mandatory to set the right value in specific register + * (offset:0x474) as per the hardware IP specification. + */ + regmap_write(dev->map, AMD_UCSI_INTR_REG, AMD_UCSI_INTR_EN); + + dev->msgs = msgs; + dev->msgs_num = num_msgs; + i2c_dw_xfer_init(dev); + regmap_write(dev->map, DW_IC_INTR_MASK, 0); + + /* Initiate messages read/write transaction */ + for (msg_wrt_idx = 0; msg_wrt_idx < num_msgs; msg_wrt_idx++) { + tx_buf = msgs[msg_wrt_idx].buf; + buf_len = msgs[msg_wrt_idx].len; + + if (!(msgs[msg_wrt_idx].flags & I2C_M_RD)) + regmap_write(dev->map, DW_IC_TX_TL, buf_len - 1); + /* + * Initiate the i2c read/write transaction of buffer length, + * and poll for bus busy status. For the last message transfer, + * update the command with stopbit enable. + */ + for (msg_itr_lmt = buf_len; msg_itr_lmt > 0; msg_itr_lmt--) { + if (msg_wrt_idx == num_msgs - 1 && msg_itr_lmt == 1) + cmd |= BIT(9); + + if (msgs[msg_wrt_idx].flags & I2C_M_RD) { + /* Due to hardware bug, need to write the same command twice. */ + regmap_write(dev->map, DW_IC_DATA_CMD, 0x100); + regmap_write(dev->map, DW_IC_DATA_CMD, 0x100 | cmd); + if (cmd) { + regmap_write(dev->map, DW_IC_TX_TL, 2 * (buf_len - 1)); + regmap_write(dev->map, DW_IC_RX_TL, 2 * (buf_len - 1)); + /* + * Need to check the stop bit. However, it cannot be + * detected from the registers so we check it always + * when read/write the last byte. + */ + status = i2c_dw_status(dev); + if (status) + return status; + + for (data_idx = 0; data_idx < buf_len; data_idx++) { + regmap_read(dev->map, DW_IC_DATA_CMD, &val); + tx_buf[data_idx] = val; + } + status = i2c_dw_check_stopbit(dev); + if (status) + return status; + } + } else { + regmap_write(dev->map, DW_IC_DATA_CMD, *tx_buf++ | cmd); + usleep_range(AMD_TIMEOUT_MIN_US, AMD_TIMEOUT_MAX_US); + } + } + status = i2c_dw_check_stopbit(dev); + if (status) + return status; + } + + return 0; +} + +static int i2c_dw_poll_tx_empty(struct dw_i2c_dev *dev) +{ + u32 val; + + return regmap_read_poll_timeout(dev->map, DW_IC_RAW_INTR_STAT, val, + val & DW_IC_INTR_TX_EMPTY, + 100, 1000); +} + +static int i2c_dw_poll_rx_full(struct dw_i2c_dev *dev) +{ + u32 val; + + return regmap_read_poll_timeout(dev->map, DW_IC_RAW_INTR_STAT, val, + val & DW_IC_INTR_RX_FULL, + 100, 1000); +} + +static int txgbe_i2c_dw_xfer_quirk(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num_msgs) +{ + struct dw_i2c_dev *dev = i2c_get_adapdata(adap); + int msg_idx, buf_len, data_idx, ret; + unsigned int val, stop = 0; + u8 *buf; + + dev->msgs = msgs; + dev->msgs_num = num_msgs; + i2c_dw_xfer_init(dev); + regmap_write(dev->map, DW_IC_INTR_MASK, 0); + + for (msg_idx = 0; msg_idx < num_msgs; msg_idx++) { + buf = msgs[msg_idx].buf; + buf_len = msgs[msg_idx].len; + + for (data_idx = 0; data_idx < buf_len; data_idx++) { + if (msg_idx == num_msgs - 1 && data_idx == buf_len - 1) + stop |= BIT(9); + + if (msgs[msg_idx].flags & I2C_M_RD) { + regmap_write(dev->map, DW_IC_DATA_CMD, 0x100 | stop); + + ret = i2c_dw_poll_rx_full(dev); + if (ret) + return ret; + + regmap_read(dev->map, DW_IC_DATA_CMD, &val); + buf[data_idx] = val; + } else { + ret = i2c_dw_poll_tx_empty(dev); + if (ret) + return ret; + + regmap_write(dev->map, DW_IC_DATA_CMD, + buf[data_idx] | stop); + } + } + } + + return num_msgs; +} + +/* + * Initiate (and continue) low level master read/write transaction. + * This function is only called from i2c_dw_isr, and pumping i2c_msg + * messages into the tx buffer. Even if the size of i2c_msg data is + * longer than the size of the tx buffer, it handles everything. + */ +static void +i2c_dw_xfer_msg(struct dw_i2c_dev *dev) +{ + struct i2c_msg *msgs = dev->msgs; + u32 intr_mask; + int tx_limit, rx_limit; + u32 addr = msgs[dev->msg_write_idx].addr; + u32 buf_len = dev->tx_buf_len; + u8 *buf = dev->tx_buf; + bool need_restart = false; + unsigned int flr; + + intr_mask = DW_IC_INTR_MASTER_MASK; + + for (; dev->msg_write_idx < dev->msgs_num; dev->msg_write_idx++) { + u32 flags = msgs[dev->msg_write_idx].flags; + + /* + * If target address has changed, we need to + * reprogram the target address in the I2C + * adapter when we are done with this transfer. + */ + if (msgs[dev->msg_write_idx].addr != addr) { + dev_err(dev->dev, + "%s: invalid target address\n", __func__); + dev->msg_err = -EINVAL; + break; + } + + if (!(dev->status & STATUS_WRITE_IN_PROGRESS)) { + /* new i2c_msg */ + buf = msgs[dev->msg_write_idx].buf; + buf_len = msgs[dev->msg_write_idx].len; + + /* If both IC_EMPTYFIFO_HOLD_MASTER_EN and + * IC_RESTART_EN are set, we must manually + * set restart bit between messages. + */ + if ((dev->master_cfg & DW_IC_CON_RESTART_EN) && + (dev->msg_write_idx > 0)) + need_restart = true; + } + + regmap_read(dev->map, DW_IC_TXFLR, &flr); + tx_limit = dev->tx_fifo_depth - flr; + + regmap_read(dev->map, DW_IC_RXFLR, &flr); + rx_limit = dev->rx_fifo_depth - flr; + + while (buf_len > 0 && tx_limit > 0 && rx_limit > 0) { + u32 cmd = 0; + + /* + * If IC_EMPTYFIFO_HOLD_MASTER_EN is set we must + * manually set the stop bit. However, it cannot be + * detected from the registers so we set it always + * when writing/reading the last byte. + */ + + /* + * i2c-core always sets the buffer length of + * I2C_FUNC_SMBUS_BLOCK_DATA to 1. The length will + * be adjusted when receiving the first byte. + * Thus we can't stop the transaction here. + */ + if (dev->msg_write_idx == dev->msgs_num - 1 && + buf_len == 1 && !(flags & I2C_M_RECV_LEN)) + cmd |= BIT(9); + + if (need_restart) { + cmd |= BIT(10); + need_restart = false; + } + + if (msgs[dev->msg_write_idx].flags & I2C_M_RD) { + + /* Avoid rx buffer overrun */ + if (dev->rx_outstanding >= dev->rx_fifo_depth) + break; + + regmap_write(dev->map, DW_IC_DATA_CMD, + cmd | 0x100); + rx_limit--; + dev->rx_outstanding++; + } else { + regmap_write(dev->map, DW_IC_DATA_CMD, + cmd | *buf++); + } + tx_limit--; buf_len--; + } + + dev->tx_buf = buf; + dev->tx_buf_len = buf_len; + + /* + * Because we don't know the buffer length in the + * I2C_FUNC_SMBUS_BLOCK_DATA case, we can't stop the + * transaction here. Also disable the TX_EMPTY IRQ + * while waiting for the data length byte to avoid the + * bogus interrupts flood. + */ + if (flags & I2C_M_RECV_LEN) { + dev->status |= STATUS_WRITE_IN_PROGRESS; + intr_mask &= ~DW_IC_INTR_TX_EMPTY; + break; + } else if (buf_len > 0) { + /* more bytes to be written */ + dev->status |= STATUS_WRITE_IN_PROGRESS; + break; + } else + dev->status &= ~STATUS_WRITE_IN_PROGRESS; + } + + /* + * If i2c_msg index search is completed, we don't need TX_EMPTY + * interrupt any more. + */ + if (dev->msg_write_idx == dev->msgs_num) + intr_mask &= ~DW_IC_INTR_TX_EMPTY; + + if (dev->msg_err) + intr_mask = 0; + + regmap_write(dev->map, DW_IC_INTR_MASK, intr_mask); +} + +static u8 +i2c_dw_recv_len(struct dw_i2c_dev *dev, u8 len) +{ + struct i2c_msg *msgs = dev->msgs; + u32 flags = msgs[dev->msg_read_idx].flags; + + /* + * Adjust the buffer length and mask the flag + * after receiving the first byte. + */ + len += (flags & I2C_CLIENT_PEC) ? 2 : 1; + dev->tx_buf_len = len - min_t(u8, len, dev->rx_outstanding); + msgs[dev->msg_read_idx].len = len; + msgs[dev->msg_read_idx].flags &= ~I2C_M_RECV_LEN; + + /* + * Received buffer length, re-enable TX_EMPTY interrupt + * to resume the SMBUS transaction. + */ + regmap_update_bits(dev->map, DW_IC_INTR_MASK, DW_IC_INTR_TX_EMPTY, + DW_IC_INTR_TX_EMPTY); + + return len; +} + +static void +i2c_dw_read(struct dw_i2c_dev *dev) +{ + struct i2c_msg *msgs = dev->msgs; + unsigned int rx_valid; + + for (; dev->msg_read_idx < dev->msgs_num; dev->msg_read_idx++) { + unsigned int tmp; + u32 len; + u8 *buf; + + if (!(msgs[dev->msg_read_idx].flags & I2C_M_RD)) + continue; + + if (!(dev->status & STATUS_READ_IN_PROGRESS)) { + len = msgs[dev->msg_read_idx].len; + buf = msgs[dev->msg_read_idx].buf; + } else { + len = dev->rx_buf_len; + buf = dev->rx_buf; + } + + regmap_read(dev->map, DW_IC_RXFLR, &rx_valid); + + for (; len > 0 && rx_valid > 0; len--, rx_valid--) { + u32 flags = msgs[dev->msg_read_idx].flags; + + regmap_read(dev->map, DW_IC_DATA_CMD, &tmp); + tmp &= DW_IC_DATA_CMD_DAT; + /* Ensure length byte is a valid value */ + if (flags & I2C_M_RECV_LEN) { + /* + * if IC_EMPTYFIFO_HOLD_MASTER_EN is set, which cannot be + * detected from the registers, the controller can be + * disabled if the STOP bit is set. But it is only set + * after receiving block data response length in + * I2C_FUNC_SMBUS_BLOCK_DATA case. That needs to read + * another byte with STOP bit set when the block data + * response length is invalid to complete the transaction. + */ + if (!tmp || tmp > I2C_SMBUS_BLOCK_MAX) + tmp = 1; + + len = i2c_dw_recv_len(dev, tmp); + } + *buf++ = tmp; + dev->rx_outstanding--; + } + + if (len > 0) { + dev->status |= STATUS_READ_IN_PROGRESS; + dev->rx_buf_len = len; + dev->rx_buf = buf; + return; + } else + dev->status &= ~STATUS_READ_IN_PROGRESS; + } +} + +/* + * Prepare controller for a transaction and call i2c_dw_xfer_msg. + */ +static int +i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + struct dw_i2c_dev *dev = i2c_get_adapdata(adap); + int ret; + + dev_dbg(dev->dev, "%s: msgs: %d\n", __func__, num); + + pm_runtime_get_sync(dev->dev); + + /* + * Initiate I2C message transfer when polling mode is enabled, + * As it is polling based transfer mechanism, which does not support + * interrupt based functionalities of existing DesignWare driver. + */ + switch (dev->flags & MODEL_MASK) { + case MODEL_AMD_NAVI_GPU: + ret = amd_i2c_dw_xfer_quirk(adap, msgs, num); + goto done_nolock; + case MODEL_WANGXUN_SP: + ret = txgbe_i2c_dw_xfer_quirk(adap, msgs, num); + goto done_nolock; + default: + break; + } + + reinit_completion(&dev->cmd_complete); + dev->msgs = msgs; + dev->msgs_num = num; + dev->cmd_err = 0; + dev->msg_write_idx = 0; + dev->msg_read_idx = 0; + dev->msg_err = 0; + dev->status = 0; + dev->abort_source = 0; + dev->rx_outstanding = 0; + + ret = i2c_dw_acquire_lock(dev); + if (ret) + goto done_nolock; + + ret = i2c_dw_wait_bus_not_busy(dev); + if (ret < 0) + goto done; + + /* Start the transfers */ + i2c_dw_xfer_init(dev); + + /* Wait for tx to complete */ + if (!wait_for_completion_timeout(&dev->cmd_complete, adap->timeout)) { + dev_err(dev->dev, "controller timed out\n"); + /* i2c_dw_init implicitly disables the adapter */ + i2c_recover_bus(&dev->adapter); + i2c_dw_init_master(dev); + ret = -ETIMEDOUT; + goto done; + } + + /* + * We must disable the adapter before returning and signaling the end + * of the current transfer. Otherwise the hardware might continue + * generating interrupts which in turn causes a race condition with + * the following transfer. Needs some more investigation if the + * additional interrupts are a hardware bug or this driver doesn't + * handle them correctly yet. + */ + __i2c_dw_disable_nowait(dev); + + if (dev->msg_err) { + ret = dev->msg_err; + goto done; + } + + /* No error */ + if (likely(!dev->cmd_err && !dev->status)) { + ret = num; + goto done; + } + + /* We have an error */ + if (dev->cmd_err == DW_IC_ERR_TX_ABRT) { + ret = i2c_dw_handle_tx_abort(dev); + goto done; + } + + if (dev->status) + dev_err(dev->dev, + "transfer terminated early - interrupt latency too high?\n"); + + ret = -EIO; + +done: + i2c_dw_release_lock(dev); + +done_nolock: + pm_runtime_mark_last_busy(dev->dev); + pm_runtime_put_autosuspend(dev->dev); + + return ret; +} + +static const struct i2c_algorithm i2c_dw_algo = { + .master_xfer = i2c_dw_xfer, + .functionality = i2c_dw_func, +}; + +static const struct i2c_adapter_quirks i2c_dw_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN, +}; + +static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev) +{ + unsigned int stat, dummy; + + /* + * The IC_INTR_STAT register just indicates "enabled" interrupts. + * The unmasked raw version of interrupt status bits is available + * in the IC_RAW_INTR_STAT register. + * + * That is, + * stat = readl(IC_INTR_STAT); + * equals to, + * stat = readl(IC_RAW_INTR_STAT) & readl(IC_INTR_MASK); + * + * The raw version might be useful for debugging purposes. + */ + regmap_read(dev->map, DW_IC_INTR_STAT, &stat); + + /* + * Do not use the IC_CLR_INTR register to clear interrupts, or + * you'll miss some interrupts, triggered during the period from + * readl(IC_INTR_STAT) to readl(IC_CLR_INTR). + * + * Instead, use the separately-prepared IC_CLR_* registers. + */ + if (stat & DW_IC_INTR_RX_UNDER) + regmap_read(dev->map, DW_IC_CLR_RX_UNDER, &dummy); + if (stat & DW_IC_INTR_RX_OVER) + regmap_read(dev->map, DW_IC_CLR_RX_OVER, &dummy); + if (stat & DW_IC_INTR_TX_OVER) + regmap_read(dev->map, DW_IC_CLR_TX_OVER, &dummy); + if (stat & DW_IC_INTR_RD_REQ) + regmap_read(dev->map, DW_IC_CLR_RD_REQ, &dummy); + if (stat & DW_IC_INTR_TX_ABRT) { + /* + * The IC_TX_ABRT_SOURCE register is cleared whenever + * the IC_CLR_TX_ABRT is read. Preserve it beforehand. + */ + regmap_read(dev->map, DW_IC_TX_ABRT_SOURCE, &dev->abort_source); + regmap_read(dev->map, DW_IC_CLR_TX_ABRT, &dummy); + } + if (stat & DW_IC_INTR_RX_DONE) + regmap_read(dev->map, DW_IC_CLR_RX_DONE, &dummy); + if (stat & DW_IC_INTR_ACTIVITY) + regmap_read(dev->map, DW_IC_CLR_ACTIVITY, &dummy); + if ((stat & DW_IC_INTR_STOP_DET) && + ((dev->rx_outstanding == 0) || (stat & DW_IC_INTR_RX_FULL))) + regmap_read(dev->map, DW_IC_CLR_STOP_DET, &dummy); + if (stat & DW_IC_INTR_START_DET) + regmap_read(dev->map, DW_IC_CLR_START_DET, &dummy); + if (stat & DW_IC_INTR_GEN_CALL) + regmap_read(dev->map, DW_IC_CLR_GEN_CALL, &dummy); + + return stat; +} + +/* + * Interrupt service routine. This gets called whenever an I2C master interrupt + * occurs. + */ +static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id) +{ + struct dw_i2c_dev *dev = dev_id; + unsigned int stat, enabled; + + regmap_read(dev->map, DW_IC_ENABLE, &enabled); + regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &stat); + if (!enabled || !(stat & ~DW_IC_INTR_ACTIVITY)) + return IRQ_NONE; + if (pm_runtime_suspended(dev->dev) || stat == GENMASK(31, 0)) + return IRQ_NONE; + dev_dbg(dev->dev, "enabled=%#x stat=%#x\n", enabled, stat); + + stat = i2c_dw_read_clear_intrbits(dev); + + if (!(dev->status & STATUS_ACTIVE)) { + /* + * Unexpected interrupt in driver point of view. State + * variables are either unset or stale so acknowledge and + * disable interrupts for suppressing further interrupts if + * interrupt really came from this HW (E.g. firmware has left + * the HW active). + */ + regmap_write(dev->map, DW_IC_INTR_MASK, 0); + return IRQ_HANDLED; + } + + if (stat & DW_IC_INTR_TX_ABRT) { + dev->cmd_err |= DW_IC_ERR_TX_ABRT; + dev->status &= ~STATUS_MASK; + dev->rx_outstanding = 0; + + /* + * Anytime TX_ABRT is set, the contents of the tx/rx + * buffers are flushed. Make sure to skip them. + */ + regmap_write(dev->map, DW_IC_INTR_MASK, 0); + goto tx_aborted; + } + + if (stat & DW_IC_INTR_RX_FULL) + i2c_dw_read(dev); + + if (stat & DW_IC_INTR_TX_EMPTY) + i2c_dw_xfer_msg(dev); + + /* + * No need to modify or disable the interrupt mask here. + * i2c_dw_xfer_msg() will take care of it according to + * the current transmit status. + */ + +tx_aborted: + if (((stat & (DW_IC_INTR_TX_ABRT | DW_IC_INTR_STOP_DET)) || dev->msg_err) && + (dev->rx_outstanding == 0)) + complete(&dev->cmd_complete); + else if (unlikely(dev->flags & ACCESS_INTR_MASK)) { + /* Workaround to trigger pending interrupt */ + regmap_read(dev->map, DW_IC_INTR_MASK, &stat); + regmap_write(dev->map, DW_IC_INTR_MASK, 0); + regmap_write(dev->map, DW_IC_INTR_MASK, stat); + } + + return IRQ_HANDLED; +} + +void i2c_dw_configure_master(struct dw_i2c_dev *dev) +{ + struct i2c_timings *t = &dev->timings; + + dev->functionality = I2C_FUNC_10BIT_ADDR | DW_IC_DEFAULT_FUNCTIONALITY; + + dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | + DW_IC_CON_RESTART_EN; + + dev->mode = DW_IC_MASTER; + + switch (t->bus_freq_hz) { + case I2C_MAX_STANDARD_MODE_FREQ: + dev->master_cfg |= DW_IC_CON_SPEED_STD; + break; + case I2C_MAX_HIGH_SPEED_MODE_FREQ: + dev->master_cfg |= DW_IC_CON_SPEED_HIGH; + break; + default: + dev->master_cfg |= DW_IC_CON_SPEED_FAST; + } +} +EXPORT_SYMBOL_GPL(i2c_dw_configure_master); + +static void i2c_dw_prepare_recovery(struct i2c_adapter *adap) +{ + struct dw_i2c_dev *dev = i2c_get_adapdata(adap); + + i2c_dw_disable(dev); + reset_control_assert(dev->rst); + i2c_dw_prepare_clk(dev, false); +} + +static void i2c_dw_unprepare_recovery(struct i2c_adapter *adap) +{ + struct dw_i2c_dev *dev = i2c_get_adapdata(adap); + + i2c_dw_prepare_clk(dev, true); + reset_control_deassert(dev->rst); + i2c_dw_init_master(dev); +} + +static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev) +{ + struct i2c_bus_recovery_info *rinfo = &dev->rinfo; + struct i2c_adapter *adap = &dev->adapter; + struct gpio_desc *gpio; + + gpio = devm_gpiod_get_optional(dev->dev, "scl", GPIOD_OUT_HIGH); + if (IS_ERR_OR_NULL(gpio)) + return PTR_ERR_OR_ZERO(gpio); + + rinfo->scl_gpiod = gpio; + + gpio = devm_gpiod_get_optional(dev->dev, "sda", GPIOD_IN); + if (IS_ERR(gpio)) + return PTR_ERR(gpio); + rinfo->sda_gpiod = gpio; + + rinfo->pinctrl = devm_pinctrl_get(dev->dev); + if (IS_ERR(rinfo->pinctrl)) { + if (PTR_ERR(rinfo->pinctrl) == -EPROBE_DEFER) + return PTR_ERR(rinfo->pinctrl); + + rinfo->pinctrl = NULL; + dev_err(dev->dev, "getting pinctrl info failed: bus recovery might not work\n"); + } else if (!rinfo->pinctrl) { + dev_dbg(dev->dev, "pinctrl is disabled, bus recovery might not work\n"); + } + + rinfo->recover_bus = i2c_generic_scl_recovery; + rinfo->prepare_recovery = i2c_dw_prepare_recovery; + rinfo->unprepare_recovery = i2c_dw_unprepare_recovery; + adap->bus_recovery_info = rinfo; + + dev_info(dev->dev, "running with gpio recovery mode! scl%s", + rinfo->sda_gpiod ? ",sda" : ""); + + return 0; +} + +static int i2c_dw_poll_adap_quirk(struct dw_i2c_dev *dev) +{ + struct i2c_adapter *adap = &dev->adapter; + int ret; + + pm_runtime_get_noresume(dev->dev); + ret = i2c_add_numbered_adapter(adap); + if (ret) + dev_err(dev->dev, "Failed to add adapter: %d\n", ret); + pm_runtime_put_noidle(dev->dev); + + return ret; +} + +static bool i2c_dw_is_model_poll(struct dw_i2c_dev *dev) +{ + switch (dev->flags & MODEL_MASK) { + case MODEL_AMD_NAVI_GPU: + case MODEL_WANGXUN_SP: + return true; + default: + return false; + } +} + +int i2c_dw_probe_master(struct dw_i2c_dev *dev) +{ + struct i2c_adapter *adap = &dev->adapter; + unsigned long irq_flags; + unsigned int ic_con; + int ret; + + init_completion(&dev->cmd_complete); + + dev->init = i2c_dw_init_master; + dev->disable = i2c_dw_disable; + + ret = i2c_dw_init_regmap(dev); + if (ret) + return ret; + + ret = i2c_dw_set_timings_master(dev); + if (ret) + return ret; + + ret = i2c_dw_set_fifo_size(dev); + if (ret) + return ret; + + /* Lock the bus for accessing DW_IC_CON */ + ret = i2c_dw_acquire_lock(dev); + if (ret) + return ret; + + /* + * On AMD platforms BIOS advertises the bus clear feature + * and enables the SCL/SDA stuck low. SMU FW does the + * bus recovery process. Driver should not ignore this BIOS + * advertisement of bus clear feature. + */ + ret = regmap_read(dev->map, DW_IC_CON, &ic_con); + i2c_dw_release_lock(dev); + if (ret) + return ret; + + if (ic_con & DW_IC_CON_BUS_CLEAR_CTRL) + dev->master_cfg |= DW_IC_CON_BUS_CLEAR_CTRL; + + ret = dev->init(dev); + if (ret) + return ret; + + snprintf(adap->name, sizeof(adap->name), + "Synopsys DesignWare I2C adapter"); + adap->retries = 3; + adap->algo = &i2c_dw_algo; + adap->quirks = &i2c_dw_quirks; + adap->dev.parent = dev->dev; + i2c_set_adapdata(adap, dev); + + if (i2c_dw_is_model_poll(dev)) + return i2c_dw_poll_adap_quirk(dev); + + if (dev->flags & ACCESS_NO_IRQ_SUSPEND) { + irq_flags = IRQF_NO_SUSPEND; + } else { + irq_flags = IRQF_SHARED | IRQF_COND_SUSPEND; + } + + ret = i2c_dw_acquire_lock(dev); + if (ret) + return ret; + + regmap_write(dev->map, DW_IC_INTR_MASK, 0); + i2c_dw_release_lock(dev); + + ret = devm_request_irq(dev->dev, dev->irq, i2c_dw_isr, irq_flags, + dev_name(dev->dev), dev); + if (ret) { + dev_err(dev->dev, "failure requesting irq %i: %d\n", + dev->irq, ret); + return ret; + } + + ret = i2c_dw_init_recovery_info(dev); + if (ret) + return ret; + + /* + * Increment PM usage count during adapter registration in order to + * avoid possible spurious runtime suspend when adapter device is + * registered to the device core and immediate resume in case bus has + * registered I2C slaves that do I2C transfers in their probe. + */ + pm_runtime_get_noresume(dev->dev); + ret = i2c_add_numbered_adapter(adap); + if (ret) + dev_err(dev->dev, "failure adding adapter: %d\n", ret); + pm_runtime_put_noidle(dev->dev); + + return ret; +} +EXPORT_SYMBOL_GPL(i2c_dw_probe_master); + +MODULE_DESCRIPTION("Synopsys DesignWare I2C bus master adapter"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-designware-pcidrv.c b/drivers/i2c/busses/i2c-designware-pcidrv.c new file mode 100644 index 000000000..61d7a27aa --- /dev/null +++ b/drivers/i2c/busses/i2c-designware-pcidrv.c @@ -0,0 +1,431 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Synopsys DesignWare I2C adapter driver (master only). + * + * Based on the TI DAVINCI I2C adapter driver. + * + * Copyright (C) 2006 Texas Instruments. + * Copyright (C) 2007 MontaVista Software Inc. + * Copyright (C) 2009 Provigent Ltd. + * Copyright (C) 2011, 2015, 2016 Intel Corporation. + */ +#include <linux/acpi.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/pm_runtime.h> +#include <linux/power_supply.h> +#include <linux/sched.h> +#include <linux/slab.h> + +#include "i2c-designware-core.h" +#include "i2c-ccgx-ucsi.h" + +#define DRIVER_NAME "i2c-designware-pci" + +enum dw_pci_ctl_id_t { + medfield, + merrifield, + baytrail, + cherrytrail, + haswell, + elkhartlake, + navi_amd, +}; + +/* + * This is a legacy structure to describe the hardware counters + * to configure signal timings on the bus. For Device Tree platforms + * one should use the respective properties and for ACPI there is + * a set of ACPI methods that provide these counters. No new + * platform should use this structure. + */ +struct dw_scl_sda_cfg { + u16 ss_hcnt; + u16 fs_hcnt; + u16 ss_lcnt; + u16 fs_lcnt; + u32 sda_hold; +}; + +struct dw_pci_controller { + u32 bus_num; + u32 flags; + struct dw_scl_sda_cfg *scl_sda_cfg; + int (*setup)(struct pci_dev *pdev, struct dw_pci_controller *c); + u32 (*get_clk_rate_khz)(struct dw_i2c_dev *dev); +}; + +/* Merrifield HCNT/LCNT/SDA hold time */ +static struct dw_scl_sda_cfg mrfld_config = { + .ss_hcnt = 0x2f8, + .fs_hcnt = 0x87, + .ss_lcnt = 0x37b, + .fs_lcnt = 0x10a, +}; + +/* BayTrail HCNT/LCNT/SDA hold time */ +static struct dw_scl_sda_cfg byt_config = { + .ss_hcnt = 0x200, + .fs_hcnt = 0x55, + .ss_lcnt = 0x200, + .fs_lcnt = 0x99, + .sda_hold = 0x6, +}; + +/* Haswell HCNT/LCNT/SDA hold time */ +static struct dw_scl_sda_cfg hsw_config = { + .ss_hcnt = 0x01b0, + .fs_hcnt = 0x48, + .ss_lcnt = 0x01fb, + .fs_lcnt = 0xa0, + .sda_hold = 0x9, +}; + +/* NAVI-AMD HCNT/LCNT/SDA hold time */ +static struct dw_scl_sda_cfg navi_amd_config = { + .ss_hcnt = 0x1ae, + .ss_lcnt = 0x23a, + .sda_hold = 0x9, +}; + +static u32 mfld_get_clk_rate_khz(struct dw_i2c_dev *dev) +{ + return 25000; +} + +static int mfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c) +{ + struct dw_i2c_dev *dev = dev_get_drvdata(&pdev->dev); + + switch (pdev->device) { + case 0x0817: + dev->timings.bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ; + fallthrough; + case 0x0818: + case 0x0819: + c->bus_num = pdev->device - 0x817 + 3; + return 0; + case 0x082C: + case 0x082D: + case 0x082E: + c->bus_num = pdev->device - 0x82C + 0; + return 0; + } + return -ENODEV; +} + +static int mrfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c) +{ + /* + * On Intel Merrifield the user visible i2c buses are enumerated + * [1..7]. So, we add 1 to shift the default range. Besides that the + * first PCI slot provides 4 functions, that's why we have to add 0 to + * the first slot and 4 to the next one. + */ + switch (PCI_SLOT(pdev->devfn)) { + case 8: + c->bus_num = PCI_FUNC(pdev->devfn) + 0 + 1; + return 0; + case 9: + c->bus_num = PCI_FUNC(pdev->devfn) + 4 + 1; + return 0; + } + return -ENODEV; +} + +static u32 ehl_get_clk_rate_khz(struct dw_i2c_dev *dev) +{ + return 100000; +} + +static u32 navi_amd_get_clk_rate_khz(struct dw_i2c_dev *dev) +{ + return 100000; +} + +static int navi_amd_setup(struct pci_dev *pdev, struct dw_pci_controller *c) +{ + struct dw_i2c_dev *dev = dev_get_drvdata(&pdev->dev); + + dev->flags |= MODEL_AMD_NAVI_GPU; + dev->timings.bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ; + return 0; +} + +static struct dw_pci_controller dw_pci_controllers[] = { + [medfield] = { + .bus_num = -1, + .setup = mfld_setup, + .get_clk_rate_khz = mfld_get_clk_rate_khz, + }, + [merrifield] = { + .bus_num = -1, + .scl_sda_cfg = &mrfld_config, + .setup = mrfld_setup, + }, + [baytrail] = { + .bus_num = -1, + .scl_sda_cfg = &byt_config, + }, + [haswell] = { + .bus_num = -1, + .scl_sda_cfg = &hsw_config, + }, + [cherrytrail] = { + .bus_num = -1, + .scl_sda_cfg = &byt_config, + }, + [elkhartlake] = { + .bus_num = -1, + .get_clk_rate_khz = ehl_get_clk_rate_khz, + }, + [navi_amd] = { + .bus_num = -1, + .scl_sda_cfg = &navi_amd_config, + .setup = navi_amd_setup, + .get_clk_rate_khz = navi_amd_get_clk_rate_khz, + }, +}; + +static int __maybe_unused i2c_dw_pci_runtime_suspend(struct device *dev) +{ + struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); + + i_dev->disable(i_dev); + return 0; +} + +static int __maybe_unused i2c_dw_pci_suspend(struct device *dev) +{ + struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); + + i2c_mark_adapter_suspended(&i_dev->adapter); + + return i2c_dw_pci_runtime_suspend(dev); +} + +static int __maybe_unused i2c_dw_pci_runtime_resume(struct device *dev) +{ + struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); + + return i_dev->init(i_dev); +} + +static int __maybe_unused i2c_dw_pci_resume(struct device *dev) +{ + struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); + int ret; + + ret = i2c_dw_pci_runtime_resume(dev); + + i2c_mark_adapter_resumed(&i_dev->adapter); + + return ret; +} + +static const struct dev_pm_ops i2c_dw_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(i2c_dw_pci_suspend, i2c_dw_pci_resume) + SET_RUNTIME_PM_OPS(i2c_dw_pci_runtime_suspend, i2c_dw_pci_runtime_resume, NULL) +}; + +static const struct property_entry dgpu_properties[] = { + /* USB-C doesn't power the system */ + PROPERTY_ENTRY_U8("scope", POWER_SUPPLY_SCOPE_DEVICE), + {} +}; + +static const struct software_node dgpu_node = { + .properties = dgpu_properties, +}; + +static int i2c_dw_pci_probe(struct pci_dev *pdev, + const struct pci_device_id *id) +{ + struct dw_i2c_dev *dev; + struct i2c_adapter *adap; + int r; + struct dw_pci_controller *controller; + struct dw_scl_sda_cfg *cfg; + struct i2c_timings *t; + + if (id->driver_data >= ARRAY_SIZE(dw_pci_controllers)) + return dev_err_probe(&pdev->dev, -EINVAL, + "Invalid driver data %ld\n", + id->driver_data); + + controller = &dw_pci_controllers[id->driver_data]; + + r = pcim_enable_device(pdev); + if (r) + return dev_err_probe(&pdev->dev, r, + "Failed to enable I2C PCI device\n"); + + pci_set_master(pdev); + + r = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev)); + if (r) + return dev_err_probe(&pdev->dev, r, + "I/O memory remapping failed\n"); + + dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + + r = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES); + if (r < 0) + return r; + + dev->get_clk_rate_khz = controller->get_clk_rate_khz; + dev->base = pcim_iomap_table(pdev)[0]; + dev->dev = &pdev->dev; + dev->irq = pci_irq_vector(pdev, 0); + dev->flags |= controller->flags; + + t = &dev->timings; + i2c_parse_fw_timings(&pdev->dev, t, false); + + pci_set_drvdata(pdev, dev); + + if (controller->setup) { + r = controller->setup(pdev, controller); + if (r) { + pci_free_irq_vectors(pdev); + return r; + } + } + + i2c_dw_adjust_bus_speed(dev); + + if (has_acpi_companion(&pdev->dev)) + i2c_dw_acpi_configure(&pdev->dev); + + r = i2c_dw_validate_speed(dev); + if (r) { + pci_free_irq_vectors(pdev); + return r; + } + + i2c_dw_configure(dev); + + if (controller->scl_sda_cfg) { + cfg = controller->scl_sda_cfg; + dev->ss_hcnt = cfg->ss_hcnt; + dev->fs_hcnt = cfg->fs_hcnt; + dev->ss_lcnt = cfg->ss_lcnt; + dev->fs_lcnt = cfg->fs_lcnt; + dev->sda_hold_time = cfg->sda_hold; + } + + adap = &dev->adapter; + adap->owner = THIS_MODULE; + adap->class = 0; + ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev)); + adap->nr = controller->bus_num; + + r = i2c_dw_probe(dev); + if (r) { + pci_free_irq_vectors(pdev); + return r; + } + + if ((dev->flags & MODEL_MASK) == MODEL_AMD_NAVI_GPU) { + dev->slave = i2c_new_ccgx_ucsi(&dev->adapter, dev->irq, &dgpu_node); + if (IS_ERR(dev->slave)) + return dev_err_probe(dev->dev, PTR_ERR(dev->slave), + "register UCSI failed\n"); + } + + pm_runtime_set_autosuspend_delay(&pdev->dev, 1000); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_put_autosuspend(&pdev->dev); + pm_runtime_allow(&pdev->dev); + + return 0; +} + +static void i2c_dw_pci_remove(struct pci_dev *pdev) +{ + struct dw_i2c_dev *dev = pci_get_drvdata(pdev); + + dev->disable(dev); + pm_runtime_forbid(&pdev->dev); + pm_runtime_get_noresume(&pdev->dev); + + i2c_del_adapter(&dev->adapter); + devm_free_irq(&pdev->dev, dev->irq, dev); + pci_free_irq_vectors(pdev); +} + +static const struct pci_device_id i2_designware_pci_ids[] = { + /* Medfield */ + { PCI_VDEVICE(INTEL, 0x0817), medfield }, + { PCI_VDEVICE(INTEL, 0x0818), medfield }, + { PCI_VDEVICE(INTEL, 0x0819), medfield }, + { PCI_VDEVICE(INTEL, 0x082C), medfield }, + { PCI_VDEVICE(INTEL, 0x082D), medfield }, + { PCI_VDEVICE(INTEL, 0x082E), medfield }, + /* Merrifield */ + { PCI_VDEVICE(INTEL, 0x1195), merrifield }, + { PCI_VDEVICE(INTEL, 0x1196), merrifield }, + /* Baytrail */ + { PCI_VDEVICE(INTEL, 0x0F41), baytrail }, + { PCI_VDEVICE(INTEL, 0x0F42), baytrail }, + { PCI_VDEVICE(INTEL, 0x0F43), baytrail }, + { PCI_VDEVICE(INTEL, 0x0F44), baytrail }, + { PCI_VDEVICE(INTEL, 0x0F45), baytrail }, + { PCI_VDEVICE(INTEL, 0x0F46), baytrail }, + { PCI_VDEVICE(INTEL, 0x0F47), baytrail }, + /* Haswell */ + { PCI_VDEVICE(INTEL, 0x9c61), haswell }, + { PCI_VDEVICE(INTEL, 0x9c62), haswell }, + /* Braswell / Cherrytrail */ + { PCI_VDEVICE(INTEL, 0x22C1), cherrytrail }, + { PCI_VDEVICE(INTEL, 0x22C2), cherrytrail }, + { PCI_VDEVICE(INTEL, 0x22C3), cherrytrail }, + { PCI_VDEVICE(INTEL, 0x22C4), cherrytrail }, + { PCI_VDEVICE(INTEL, 0x22C5), cherrytrail }, + { PCI_VDEVICE(INTEL, 0x22C6), cherrytrail }, + { PCI_VDEVICE(INTEL, 0x22C7), cherrytrail }, + /* Elkhart Lake (PSE I2C) */ + { PCI_VDEVICE(INTEL, 0x4bb9), elkhartlake }, + { PCI_VDEVICE(INTEL, 0x4bba), elkhartlake }, + { PCI_VDEVICE(INTEL, 0x4bbb), elkhartlake }, + { PCI_VDEVICE(INTEL, 0x4bbc), elkhartlake }, + { PCI_VDEVICE(INTEL, 0x4bbd), elkhartlake }, + { PCI_VDEVICE(INTEL, 0x4bbe), elkhartlake }, + { PCI_VDEVICE(INTEL, 0x4bbf), elkhartlake }, + { PCI_VDEVICE(INTEL, 0x4bc0), elkhartlake }, + /* AMD NAVI */ + { PCI_VDEVICE(ATI, 0x7314), navi_amd }, + { PCI_VDEVICE(ATI, 0x73a4), navi_amd }, + { PCI_VDEVICE(ATI, 0x73e4), navi_amd }, + { PCI_VDEVICE(ATI, 0x73c4), navi_amd }, + { PCI_VDEVICE(ATI, 0x7444), navi_amd }, + { PCI_VDEVICE(ATI, 0x7464), navi_amd }, + { 0,} +}; +MODULE_DEVICE_TABLE(pci, i2_designware_pci_ids); + +static struct pci_driver dw_i2c_driver = { + .name = DRIVER_NAME, + .id_table = i2_designware_pci_ids, + .probe = i2c_dw_pci_probe, + .remove = i2c_dw_pci_remove, + .driver = { + .pm = &i2c_dw_pm_ops, + }, +}; +module_pci_driver(dw_i2c_driver); + +/* Work with hotplug and coldplug */ +MODULE_ALIAS("i2c_designware-pci"); +MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>"); +MODULE_DESCRIPTION("Synopsys DesignWare PCI I2C bus adapter"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c new file mode 100644 index 000000000..855b698e9 --- /dev/null +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -0,0 +1,510 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Synopsys DesignWare I2C adapter driver. + * + * Based on the TI DAVINCI I2C adapter driver. + * + * Copyright (C) 2006 Texas Instruments. + * Copyright (C) 2007 MontaVista Software Inc. + * Copyright (C) 2009 Provigent Ltd. + */ +#include <linux/acpi.h> +#include <linux/clk-provider.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmi.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> +#include <linux/property.h> +#include <linux/regmap.h> +#include <linux/reset.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/suspend.h> +#include <linux/units.h> + +#include "i2c-designware-core.h" + +static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev) +{ + return clk_get_rate(dev->clk) / KILO; +} + +#ifdef CONFIG_ACPI +static const struct acpi_device_id dw_i2c_acpi_match[] = { + { "INT33C2", 0 }, + { "INT33C3", 0 }, + { "INT3432", 0 }, + { "INT3433", 0 }, + { "80860F41", ACCESS_NO_IRQ_SUSPEND }, + { "808622C1", ACCESS_NO_IRQ_SUSPEND }, + { "AMD0010", ACCESS_INTR_MASK }, + { "AMDI0010", ACCESS_INTR_MASK }, + { "AMDI0019", ACCESS_INTR_MASK | ARBITRATION_SEMAPHORE }, + { "AMDI0510", 0 }, + { "APMC0D0F", 0 }, + { "HISI02A1", 0 }, + { "HISI02A2", 0 }, + { "HISI02A3", 0 }, + { "HYGO0010", ACCESS_INTR_MASK }, + { } +}; +MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match); +#endif + +#ifdef CONFIG_OF +#define BT1_I2C_CTL 0x100 +#define BT1_I2C_CTL_ADDR_MASK GENMASK(7, 0) +#define BT1_I2C_CTL_WR BIT(8) +#define BT1_I2C_CTL_GO BIT(31) +#define BT1_I2C_DI 0x104 +#define BT1_I2C_DO 0x108 + +static int bt1_i2c_read(void *context, unsigned int reg, unsigned int *val) +{ + struct dw_i2c_dev *dev = context; + int ret; + + /* + * Note these methods shouldn't ever fail because the system controller + * registers are memory mapped. We check the return value just in case. + */ + ret = regmap_write(dev->sysmap, BT1_I2C_CTL, + BT1_I2C_CTL_GO | (reg & BT1_I2C_CTL_ADDR_MASK)); + if (ret) + return ret; + + return regmap_read(dev->sysmap, BT1_I2C_DO, val); +} + +static int bt1_i2c_write(void *context, unsigned int reg, unsigned int val) +{ + struct dw_i2c_dev *dev = context; + int ret; + + ret = regmap_write(dev->sysmap, BT1_I2C_DI, val); + if (ret) + return ret; + + return regmap_write(dev->sysmap, BT1_I2C_CTL, + BT1_I2C_CTL_GO | BT1_I2C_CTL_WR | (reg & BT1_I2C_CTL_ADDR_MASK)); +} + +static struct regmap_config bt1_i2c_cfg = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .fast_io = true, + .reg_read = bt1_i2c_read, + .reg_write = bt1_i2c_write, + .max_register = DW_IC_COMP_TYPE, +}; + +static int bt1_i2c_request_regs(struct dw_i2c_dev *dev) +{ + dev->sysmap = syscon_node_to_regmap(dev->dev->of_node->parent); + if (IS_ERR(dev->sysmap)) + return PTR_ERR(dev->sysmap); + + dev->map = devm_regmap_init(dev->dev, NULL, dev, &bt1_i2c_cfg); + return PTR_ERR_OR_ZERO(dev->map); +} + +#define MSCC_ICPU_CFG_TWI_DELAY 0x0 +#define MSCC_ICPU_CFG_TWI_DELAY_ENABLE BIT(0) +#define MSCC_ICPU_CFG_TWI_SPIKE_FILTER 0x4 + +static int mscc_twi_set_sda_hold_time(struct dw_i2c_dev *dev) +{ + writel((dev->sda_hold_time << 1) | MSCC_ICPU_CFG_TWI_DELAY_ENABLE, + dev->ext + MSCC_ICPU_CFG_TWI_DELAY); + + return 0; +} + +static int dw_i2c_of_configure(struct platform_device *pdev) +{ + struct dw_i2c_dev *dev = platform_get_drvdata(pdev); + + switch (dev->flags & MODEL_MASK) { + case MODEL_MSCC_OCELOT: + dev->ext = devm_platform_ioremap_resource(pdev, 1); + if (!IS_ERR(dev->ext)) + dev->set_sda_hold_time = mscc_twi_set_sda_hold_time; + break; + default: + break; + } + + return 0; +} + +static const struct of_device_id dw_i2c_of_match[] = { + { .compatible = "snps,designware-i2c", }, + { .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT }, + { .compatible = "baikal,bt1-sys-i2c", .data = (void *)MODEL_BAIKAL_BT1 }, + {}, +}; +MODULE_DEVICE_TABLE(of, dw_i2c_of_match); +#else +static int bt1_i2c_request_regs(struct dw_i2c_dev *dev) +{ + return -ENODEV; +} + +static inline int dw_i2c_of_configure(struct platform_device *pdev) +{ + return -ENODEV; +} +#endif + +static int txgbe_i2c_request_regs(struct dw_i2c_dev *dev) +{ + dev->map = dev_get_regmap(dev->dev->parent, NULL); + if (!dev->map) + return -ENODEV; + + return 0; +} + +static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev) +{ + pm_runtime_disable(dev->dev); + + if (dev->shared_with_punit) + pm_runtime_put_noidle(dev->dev); +} + +static int dw_i2c_plat_request_regs(struct dw_i2c_dev *dev) +{ + struct platform_device *pdev = to_platform_device(dev->dev); + int ret; + + switch (dev->flags & MODEL_MASK) { + case MODEL_BAIKAL_BT1: + ret = bt1_i2c_request_regs(dev); + break; + case MODEL_WANGXUN_SP: + ret = txgbe_i2c_request_regs(dev); + break; + default: + dev->base = devm_platform_ioremap_resource(pdev, 0); + ret = PTR_ERR_OR_ZERO(dev->base); + break; + } + + return ret; +} + +static const struct dmi_system_id dw_i2c_hwmon_class_dmi[] = { + { + .ident = "Qtechnology QT5222", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Qtechnology"), + DMI_MATCH(DMI_PRODUCT_NAME, "QT5222"), + }, + }, + { } /* terminate list */ +}; + +static const struct i2c_dw_semaphore_callbacks i2c_dw_semaphore_cb_table[] = { +#ifdef CONFIG_I2C_DESIGNWARE_BAYTRAIL + { + .probe = i2c_dw_baytrail_probe_lock_support, + }, +#endif +#ifdef CONFIG_I2C_DESIGNWARE_AMDPSP + { + .probe = i2c_dw_amdpsp_probe_lock_support, + }, +#endif + {} +}; + +static int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev) +{ + const struct i2c_dw_semaphore_callbacks *ptr; + int i = 0; + int ret; + + ptr = i2c_dw_semaphore_cb_table; + + dev->semaphore_idx = -1; + + while (ptr->probe) { + ret = ptr->probe(dev); + if (ret) { + /* + * If there is no semaphore device attached to this + * controller, we shouldn't abort general i2c_controller + * probe. + */ + if (ret != -ENODEV) + return ret; + + i++; + ptr++; + continue; + } + + dev->semaphore_idx = i; + break; + } + + return 0; +} + +static void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev) +{ + if (dev->semaphore_idx < 0) + return; + + if (i2c_dw_semaphore_cb_table[dev->semaphore_idx].remove) + i2c_dw_semaphore_cb_table[dev->semaphore_idx].remove(dev); +} + +static int dw_i2c_plat_probe(struct platform_device *pdev) +{ + struct i2c_adapter *adap; + struct dw_i2c_dev *dev; + struct i2c_timings *t; + int irq, ret; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + + dev->flags = (uintptr_t)device_get_match_data(&pdev->dev); + if (device_property_present(&pdev->dev, "wx,i2c-snps-model")) + dev->flags = MODEL_WANGXUN_SP; + + dev->dev = &pdev->dev; + dev->irq = irq; + platform_set_drvdata(pdev, dev); + + ret = dw_i2c_plat_request_regs(dev); + if (ret) + return ret; + + dev->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL); + if (IS_ERR(dev->rst)) + return PTR_ERR(dev->rst); + + reset_control_deassert(dev->rst); + + t = &dev->timings; + i2c_parse_fw_timings(&pdev->dev, t, false); + + i2c_dw_adjust_bus_speed(dev); + + if (pdev->dev.of_node) + dw_i2c_of_configure(pdev); + + if (has_acpi_companion(&pdev->dev)) + i2c_dw_acpi_configure(&pdev->dev); + + ret = i2c_dw_validate_speed(dev); + if (ret) + goto exit_reset; + + ret = i2c_dw_probe_lock_support(dev); + if (ret) + goto exit_reset; + + i2c_dw_configure(dev); + + /* Optional interface clock */ + dev->pclk = devm_clk_get_optional(&pdev->dev, "pclk"); + if (IS_ERR(dev->pclk)) { + ret = PTR_ERR(dev->pclk); + goto exit_reset; + } + + dev->clk = devm_clk_get_optional(&pdev->dev, NULL); + if (IS_ERR(dev->clk)) { + ret = PTR_ERR(dev->clk); + goto exit_reset; + } + + ret = i2c_dw_prepare_clk(dev, true); + if (ret) + goto exit_reset; + + if (dev->clk) { + u64 clk_khz; + + dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; + clk_khz = dev->get_clk_rate_khz(dev); + + if (!dev->sda_hold_time && t->sda_hold_ns) + dev->sda_hold_time = + DIV_S64_ROUND_CLOSEST(clk_khz * t->sda_hold_ns, MICRO); + } + + adap = &dev->adapter; + adap->owner = THIS_MODULE; + adap->class = dmi_check_system(dw_i2c_hwmon_class_dmi) ? + I2C_CLASS_HWMON : I2C_CLASS_DEPRECATED; + ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev)); + adap->dev.of_node = pdev->dev.of_node; + adap->nr = -1; + + if (dev->flags & ACCESS_NO_IRQ_SUSPEND) { + dev_pm_set_driver_flags(&pdev->dev, + DPM_FLAG_SMART_PREPARE); + } else { + dev_pm_set_driver_flags(&pdev->dev, + DPM_FLAG_SMART_PREPARE | + DPM_FLAG_SMART_SUSPEND); + } + + device_enable_async_suspend(&pdev->dev); + + /* The code below assumes runtime PM to be disabled. */ + WARN_ON(pm_runtime_enabled(&pdev->dev)); + + pm_runtime_set_autosuspend_delay(&pdev->dev, 1000); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + + if (dev->shared_with_punit) + pm_runtime_get_noresume(&pdev->dev); + + pm_runtime_enable(&pdev->dev); + + ret = i2c_dw_probe(dev); + if (ret) + goto exit_probe; + + return ret; + +exit_probe: + dw_i2c_plat_pm_cleanup(dev); +exit_reset: + reset_control_assert(dev->rst); + return ret; +} + +static void dw_i2c_plat_remove(struct platform_device *pdev) +{ + struct dw_i2c_dev *dev = platform_get_drvdata(pdev); + + pm_runtime_get_sync(&pdev->dev); + + i2c_del_adapter(&dev->adapter); + + dev->disable(dev); + + pm_runtime_dont_use_autosuspend(&pdev->dev); + pm_runtime_put_sync(&pdev->dev); + dw_i2c_plat_pm_cleanup(dev); + + i2c_dw_remove_lock_support(dev); + + reset_control_assert(dev->rst); +} + +static int dw_i2c_plat_prepare(struct device *dev) +{ + /* + * If the ACPI companion device object is present for this device, it + * may be accessed during suspend and resume of other devices via I2C + * operation regions, so tell the PM core and middle layers to avoid + * skipping system suspend/resume callbacks for it in that case. + */ + return !has_acpi_companion(dev); +} + +static int dw_i2c_plat_runtime_suspend(struct device *dev) +{ + struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); + + if (i_dev->shared_with_punit) + return 0; + + i_dev->disable(i_dev); + i2c_dw_prepare_clk(i_dev, false); + + return 0; +} + +static int dw_i2c_plat_suspend(struct device *dev) +{ + struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); + + i2c_mark_adapter_suspended(&i_dev->adapter); + + return dw_i2c_plat_runtime_suspend(dev); +} + +static int dw_i2c_plat_runtime_resume(struct device *dev) +{ + struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); + + if (!i_dev->shared_with_punit) + i2c_dw_prepare_clk(i_dev, true); + + i_dev->init(i_dev); + + return 0; +} + +static int dw_i2c_plat_resume(struct device *dev) +{ + struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); + + dw_i2c_plat_runtime_resume(dev); + i2c_mark_adapter_resumed(&i_dev->adapter); + + return 0; +} + +static const struct dev_pm_ops dw_i2c_dev_pm_ops = { + .prepare = pm_sleep_ptr(dw_i2c_plat_prepare), + LATE_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume) + RUNTIME_PM_OPS(dw_i2c_plat_runtime_suspend, dw_i2c_plat_runtime_resume, NULL) +}; + +/* Work with hotplug and coldplug */ +MODULE_ALIAS("platform:i2c_designware"); + +static struct platform_driver dw_i2c_driver = { + .probe = dw_i2c_plat_probe, + .remove_new = dw_i2c_plat_remove, + .driver = { + .name = "i2c_designware", + .of_match_table = of_match_ptr(dw_i2c_of_match), + .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match), + .pm = pm_ptr(&dw_i2c_dev_pm_ops), + }, +}; + +static int __init dw_i2c_init_driver(void) +{ + return platform_driver_register(&dw_i2c_driver); +} +subsys_initcall(dw_i2c_init_driver); + +static void __exit dw_i2c_exit_driver(void) +{ + platform_driver_unregister(&dw_i2c_driver); +} +module_exit(dw_i2c_exit_driver); + +MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>"); +MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-designware-slave.c b/drivers/i2c/busses/i2c-designware-slave.c new file mode 100644 index 000000000..2e079cf20 --- /dev/null +++ b/drivers/i2c/busses/i2c-designware-slave.c @@ -0,0 +1,281 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Synopsys DesignWare I2C adapter driver (slave only). + * + * Based on the Synopsys DesignWare I2C adapter driver (master). + * + * Copyright (C) 2016 Synopsys Inc. + */ +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/pm_runtime.h> +#include <linux/regmap.h> + +#include "i2c-designware-core.h" + +static void i2c_dw_configure_fifo_slave(struct dw_i2c_dev *dev) +{ + /* Configure Tx/Rx FIFO threshold levels. */ + regmap_write(dev->map, DW_IC_TX_TL, 0); + regmap_write(dev->map, DW_IC_RX_TL, 0); + + /* Configure the I2C slave. */ + regmap_write(dev->map, DW_IC_CON, dev->slave_cfg); + regmap_write(dev->map, DW_IC_INTR_MASK, DW_IC_INTR_SLAVE_MASK); +} + +/** + * i2c_dw_init_slave() - Initialize the designware i2c slave hardware + * @dev: device private data + * + * This function configures and enables the I2C in slave mode. + * This function is called during I2C init function, and in case of timeout at + * run time. + */ +static int i2c_dw_init_slave(struct dw_i2c_dev *dev) +{ + int ret; + + ret = i2c_dw_acquire_lock(dev); + if (ret) + return ret; + + /* Disable the adapter. */ + __i2c_dw_disable(dev); + + /* Write SDA hold time if supported */ + if (dev->sda_hold_time) + regmap_write(dev->map, DW_IC_SDA_HOLD, dev->sda_hold_time); + + i2c_dw_configure_fifo_slave(dev); + i2c_dw_release_lock(dev); + + return 0; +} + +static int i2c_dw_reg_slave(struct i2c_client *slave) +{ + struct dw_i2c_dev *dev = i2c_get_adapdata(slave->adapter); + + if (dev->slave) + return -EBUSY; + if (slave->flags & I2C_CLIENT_TEN) + return -EAFNOSUPPORT; + pm_runtime_get_sync(dev->dev); + + /* + * Set slave address in the IC_SAR register, + * the address to which the DW_apb_i2c responds. + */ + __i2c_dw_disable_nowait(dev); + regmap_write(dev->map, DW_IC_SAR, slave->addr); + dev->slave = slave; + + __i2c_dw_enable(dev); + + dev->status = 0; + + return 0; +} + +static int i2c_dw_unreg_slave(struct i2c_client *slave) +{ + struct dw_i2c_dev *dev = i2c_get_adapdata(slave->adapter); + + regmap_write(dev->map, DW_IC_INTR_MASK, 0); + dev->disable(dev); + synchronize_irq(dev->irq); + dev->slave = NULL; + pm_runtime_put(dev->dev); + + return 0; +} + +static u32 i2c_dw_read_clear_intrbits_slave(struct dw_i2c_dev *dev) +{ + unsigned int stat, dummy; + + /* + * The IC_INTR_STAT register just indicates "enabled" interrupts. + * The unmasked raw version of interrupt status bits is available + * in the IC_RAW_INTR_STAT register. + * + * That is, + * stat = readl(IC_INTR_STAT); + * equals to, + * stat = readl(IC_RAW_INTR_STAT) & readl(IC_INTR_MASK); + * + * The raw version might be useful for debugging purposes. + */ + regmap_read(dev->map, DW_IC_INTR_STAT, &stat); + + /* + * Do not use the IC_CLR_INTR register to clear interrupts, or + * you'll miss some interrupts, triggered during the period from + * readl(IC_INTR_STAT) to readl(IC_CLR_INTR). + * + * Instead, use the separately-prepared IC_CLR_* registers. + */ + if (stat & DW_IC_INTR_TX_ABRT) + regmap_read(dev->map, DW_IC_CLR_TX_ABRT, &dummy); + if (stat & DW_IC_INTR_RX_UNDER) + regmap_read(dev->map, DW_IC_CLR_RX_UNDER, &dummy); + if (stat & DW_IC_INTR_RX_OVER) + regmap_read(dev->map, DW_IC_CLR_RX_OVER, &dummy); + if (stat & DW_IC_INTR_TX_OVER) + regmap_read(dev->map, DW_IC_CLR_TX_OVER, &dummy); + if (stat & DW_IC_INTR_RX_DONE) + regmap_read(dev->map, DW_IC_CLR_RX_DONE, &dummy); + if (stat & DW_IC_INTR_ACTIVITY) + regmap_read(dev->map, DW_IC_CLR_ACTIVITY, &dummy); + if (stat & DW_IC_INTR_STOP_DET) + regmap_read(dev->map, DW_IC_CLR_STOP_DET, &dummy); + if (stat & DW_IC_INTR_START_DET) + regmap_read(dev->map, DW_IC_CLR_START_DET, &dummy); + if (stat & DW_IC_INTR_GEN_CALL) + regmap_read(dev->map, DW_IC_CLR_GEN_CALL, &dummy); + + return stat; +} + +/* + * Interrupt service routine. This gets called whenever an I2C slave interrupt + * occurs. + */ +static irqreturn_t i2c_dw_isr_slave(int this_irq, void *dev_id) +{ + struct dw_i2c_dev *dev = dev_id; + unsigned int raw_stat, stat, enabled, tmp; + u8 val = 0, slave_activity; + + regmap_read(dev->map, DW_IC_ENABLE, &enabled); + regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &raw_stat); + regmap_read(dev->map, DW_IC_STATUS, &tmp); + slave_activity = ((tmp & DW_IC_STATUS_SLAVE_ACTIVITY) >> 6); + + if (!enabled || !(raw_stat & ~DW_IC_INTR_ACTIVITY) || !dev->slave) + return IRQ_NONE; + + stat = i2c_dw_read_clear_intrbits_slave(dev); + dev_dbg(dev->dev, + "%#x STATUS SLAVE_ACTIVITY=%#x : RAW_INTR_STAT=%#x : INTR_STAT=%#x\n", + enabled, slave_activity, raw_stat, stat); + + if (stat & DW_IC_INTR_RX_FULL) { + if (!(dev->status & STATUS_WRITE_IN_PROGRESS)) { + dev->status |= STATUS_WRITE_IN_PROGRESS; + dev->status &= ~STATUS_READ_IN_PROGRESS; + i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_REQUESTED, + &val); + } + + do { + regmap_read(dev->map, DW_IC_DATA_CMD, &tmp); + if (tmp & DW_IC_DATA_CMD_FIRST_DATA_BYTE) + i2c_slave_event(dev->slave, + I2C_SLAVE_WRITE_REQUESTED, + &val); + val = tmp; + i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_RECEIVED, + &val); + regmap_read(dev->map, DW_IC_STATUS, &tmp); + } while (tmp & DW_IC_STATUS_RFNE); + } + + if (stat & DW_IC_INTR_RD_REQ) { + if (slave_activity) { + regmap_read(dev->map, DW_IC_CLR_RD_REQ, &tmp); + + if (!(dev->status & STATUS_READ_IN_PROGRESS)) { + i2c_slave_event(dev->slave, + I2C_SLAVE_READ_REQUESTED, + &val); + dev->status |= STATUS_READ_IN_PROGRESS; + dev->status &= ~STATUS_WRITE_IN_PROGRESS; + } else { + i2c_slave_event(dev->slave, + I2C_SLAVE_READ_PROCESSED, + &val); + } + regmap_write(dev->map, DW_IC_DATA_CMD, val); + } + } + + if (stat & DW_IC_INTR_STOP_DET) + i2c_slave_event(dev->slave, I2C_SLAVE_STOP, &val); + + return IRQ_HANDLED; +} + +static const struct i2c_algorithm i2c_dw_algo = { + .functionality = i2c_dw_func, + .reg_slave = i2c_dw_reg_slave, + .unreg_slave = i2c_dw_unreg_slave, +}; + +void i2c_dw_configure_slave(struct dw_i2c_dev *dev) +{ + dev->functionality = I2C_FUNC_SLAVE | DW_IC_DEFAULT_FUNCTIONALITY; + + dev->slave_cfg = DW_IC_CON_RX_FIFO_FULL_HLD_CTRL | + DW_IC_CON_RESTART_EN | DW_IC_CON_STOP_DET_IFADDRESSED; + + dev->mode = DW_IC_SLAVE; +} +EXPORT_SYMBOL_GPL(i2c_dw_configure_slave); + +int i2c_dw_probe_slave(struct dw_i2c_dev *dev) +{ + struct i2c_adapter *adap = &dev->adapter; + int ret; + + dev->init = i2c_dw_init_slave; + dev->disable = i2c_dw_disable; + + ret = i2c_dw_init_regmap(dev); + if (ret) + return ret; + + ret = i2c_dw_set_sda_hold(dev); + if (ret) + return ret; + + ret = i2c_dw_set_fifo_size(dev); + if (ret) + return ret; + + ret = dev->init(dev); + if (ret) + return ret; + + snprintf(adap->name, sizeof(adap->name), + "Synopsys DesignWare I2C Slave adapter"); + adap->retries = 3; + adap->algo = &i2c_dw_algo; + adap->dev.parent = dev->dev; + i2c_set_adapdata(adap, dev); + + ret = devm_request_irq(dev->dev, dev->irq, i2c_dw_isr_slave, + IRQF_SHARED, dev_name(dev->dev), dev); + if (ret) { + dev_err(dev->dev, "failure requesting irq %i: %d\n", + dev->irq, ret); + return ret; + } + + ret = i2c_add_numbered_adapter(adap); + if (ret) + dev_err(dev->dev, "failure adding adapter: %d\n", ret); + + return ret; +} +EXPORT_SYMBOL_GPL(i2c_dw_probe_slave); + +MODULE_AUTHOR("Luis Oliveira <lolivei@synopsys.com>"); +MODULE_DESCRIPTION("Synopsys DesignWare I2C bus slave adapter"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-digicolor.c b/drivers/i2c/busses/i2c-digicolor.c new file mode 100644 index 000000000..3462f2bc0 --- /dev/null +++ b/drivers/i2c/busses/i2c-digicolor.c @@ -0,0 +1,376 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * I2C bus driver for Conexant Digicolor SoCs + * + * Author: Baruch Siach <baruch@tkos.co.il> + * + * Copyright (C) 2015 Paradox Innovation Ltd. + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> + +#define TIMEOUT_MS 100 + +#define II_CONTROL 0x0 +#define II_CONTROL_LOCAL_RESET BIT(0) + +#define II_CLOCKTIME 0x1 + +#define II_COMMAND 0x2 +#define II_CMD_START 1 +#define II_CMD_RESTART 2 +#define II_CMD_SEND_ACK 3 +#define II_CMD_GET_ACK 6 +#define II_CMD_GET_NOACK 7 +#define II_CMD_STOP 10 +#define II_COMMAND_GO BIT(7) +#define II_COMMAND_COMPLETION_STATUS(r) (((r) >> 5) & 3) +#define II_CMD_STATUS_NORMAL 0 +#define II_CMD_STATUS_ACK_GOOD 1 +#define II_CMD_STATUS_ACK_BAD 2 +#define II_CMD_STATUS_ABORT 3 + +#define II_DATA 0x3 +#define II_INTFLAG_CLEAR 0x8 +#define II_INTENABLE 0xa + +struct dc_i2c { + struct i2c_adapter adap; + struct device *dev; + void __iomem *regs; + struct clk *clk; + unsigned int frequency; + + struct i2c_msg *msg; + unsigned int msgbuf_ptr; + int last; + spinlock_t lock; + struct completion done; + int state; + int error; +}; + +enum { + STATE_IDLE, + STATE_START, + STATE_ADDR, + STATE_WRITE, + STATE_READ, + STATE_STOP, +}; + +static void dc_i2c_cmd(struct dc_i2c *i2c, u8 cmd) +{ + writeb_relaxed(cmd | II_COMMAND_GO, i2c->regs + II_COMMAND); +} + +static u8 dc_i2c_addr_cmd(struct i2c_msg *msg) +{ + u8 addr = (msg->addr & 0x7f) << 1; + + if (msg->flags & I2C_M_RD) + addr |= 1; + + return addr; +} + +static void dc_i2c_data(struct dc_i2c *i2c, u8 data) +{ + writeb_relaxed(data, i2c->regs + II_DATA); +} + +static void dc_i2c_write_byte(struct dc_i2c *i2c, u8 byte) +{ + dc_i2c_data(i2c, byte); + dc_i2c_cmd(i2c, II_CMD_SEND_ACK); +} + +static void dc_i2c_write_buf(struct dc_i2c *i2c) +{ + dc_i2c_write_byte(i2c, i2c->msg->buf[i2c->msgbuf_ptr++]); +} + +static void dc_i2c_next_read(struct dc_i2c *i2c) +{ + bool last = (i2c->msgbuf_ptr + 1 == i2c->msg->len); + + dc_i2c_cmd(i2c, last ? II_CMD_GET_NOACK : II_CMD_GET_ACK); +} + +static void dc_i2c_stop(struct dc_i2c *i2c) +{ + i2c->state = STATE_STOP; + if (i2c->last) + dc_i2c_cmd(i2c, II_CMD_STOP); + else + complete(&i2c->done); +} + +static u8 dc_i2c_read_byte(struct dc_i2c *i2c) +{ + return readb_relaxed(i2c->regs + II_DATA); +} + +static void dc_i2c_read_buf(struct dc_i2c *i2c) +{ + i2c->msg->buf[i2c->msgbuf_ptr++] = dc_i2c_read_byte(i2c); + dc_i2c_next_read(i2c); +} + +static void dc_i2c_set_irq(struct dc_i2c *i2c, int enable) +{ + if (enable) + writeb_relaxed(1, i2c->regs + II_INTFLAG_CLEAR); + writeb_relaxed(!!enable, i2c->regs + II_INTENABLE); +} + +static int dc_i2c_cmd_status(struct dc_i2c *i2c) +{ + u8 cmd = readb_relaxed(i2c->regs + II_COMMAND); + + return II_COMMAND_COMPLETION_STATUS(cmd); +} + +static void dc_i2c_start_msg(struct dc_i2c *i2c, int first) +{ + struct i2c_msg *msg = i2c->msg; + + if (!(msg->flags & I2C_M_NOSTART)) { + i2c->state = STATE_START; + dc_i2c_cmd(i2c, first ? II_CMD_START : II_CMD_RESTART); + } else if (msg->flags & I2C_M_RD) { + i2c->state = STATE_READ; + dc_i2c_next_read(i2c); + } else { + i2c->state = STATE_WRITE; + dc_i2c_write_buf(i2c); + } +} + +static irqreturn_t dc_i2c_irq(int irq, void *dev_id) +{ + struct dc_i2c *i2c = dev_id; + int cmd_status = dc_i2c_cmd_status(i2c); + u8 addr_cmd; + + writeb_relaxed(1, i2c->regs + II_INTFLAG_CLEAR); + + spin_lock(&i2c->lock); + + if (cmd_status == II_CMD_STATUS_ACK_BAD + || cmd_status == II_CMD_STATUS_ABORT) { + i2c->error = -EIO; + complete(&i2c->done); + goto out; + } + + switch (i2c->state) { + case STATE_START: + addr_cmd = dc_i2c_addr_cmd(i2c->msg); + dc_i2c_write_byte(i2c, addr_cmd); + i2c->state = STATE_ADDR; + break; + case STATE_ADDR: + if (i2c->msg->flags & I2C_M_RD) { + dc_i2c_next_read(i2c); + i2c->state = STATE_READ; + break; + } + i2c->state = STATE_WRITE; + fallthrough; + case STATE_WRITE: + if (i2c->msgbuf_ptr < i2c->msg->len) + dc_i2c_write_buf(i2c); + else + dc_i2c_stop(i2c); + break; + case STATE_READ: + if (i2c->msgbuf_ptr < i2c->msg->len) + dc_i2c_read_buf(i2c); + else + dc_i2c_stop(i2c); + break; + case STATE_STOP: + i2c->state = STATE_IDLE; + complete(&i2c->done); + break; + } + +out: + spin_unlock(&i2c->lock); + return IRQ_HANDLED; +} + +static int dc_i2c_xfer_msg(struct dc_i2c *i2c, struct i2c_msg *msg, int first, + int last) +{ + unsigned long timeout = msecs_to_jiffies(TIMEOUT_MS); + unsigned long flags; + + spin_lock_irqsave(&i2c->lock, flags); + i2c->msg = msg; + i2c->msgbuf_ptr = 0; + i2c->last = last; + i2c->error = 0; + + reinit_completion(&i2c->done); + dc_i2c_set_irq(i2c, 1); + dc_i2c_start_msg(i2c, first); + spin_unlock_irqrestore(&i2c->lock, flags); + + timeout = wait_for_completion_timeout(&i2c->done, timeout); + dc_i2c_set_irq(i2c, 0); + if (timeout == 0) { + i2c->state = STATE_IDLE; + return -ETIMEDOUT; + } + + if (i2c->error) + return i2c->error; + + return 0; +} + +static int dc_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + struct dc_i2c *i2c = adap->algo_data; + int i, ret; + + for (i = 0; i < num; i++) { + ret = dc_i2c_xfer_msg(i2c, &msgs[i], i == 0, i == num - 1); + if (ret) + return ret; + } + + return num; +} + +static int dc_i2c_init_hw(struct dc_i2c *i2c) +{ + unsigned long clk_rate = clk_get_rate(i2c->clk); + unsigned int clocktime; + + writeb_relaxed(II_CONTROL_LOCAL_RESET, i2c->regs + II_CONTROL); + udelay(100); + writeb_relaxed(0, i2c->regs + II_CONTROL); + udelay(100); + + clocktime = DIV_ROUND_UP(clk_rate, 64 * i2c->frequency); + if (clocktime < 1 || clocktime > 0xff) { + dev_err(i2c->dev, "can't set bus speed of %u Hz\n", + i2c->frequency); + return -EINVAL; + } + writeb_relaxed(clocktime - 1, i2c->regs + II_CLOCKTIME); + + return 0; +} + +static u32 dc_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_NOSTART; +} + +static const struct i2c_algorithm dc_i2c_algorithm = { + .master_xfer = dc_i2c_xfer, + .functionality = dc_i2c_func, +}; + +static int dc_i2c_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct dc_i2c *i2c; + int ret = 0, irq; + + i2c = devm_kzalloc(&pdev->dev, sizeof(struct dc_i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + if (of_property_read_u32(pdev->dev.of_node, "clock-frequency", + &i2c->frequency)) + i2c->frequency = I2C_MAX_STANDARD_MODE_FREQ; + + i2c->dev = &pdev->dev; + platform_set_drvdata(pdev, i2c); + + spin_lock_init(&i2c->lock); + init_completion(&i2c->done); + + i2c->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(i2c->clk)) + return PTR_ERR(i2c->clk); + + i2c->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c->regs)) + return PTR_ERR(i2c->regs); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + ret = devm_request_irq(&pdev->dev, irq, dc_i2c_irq, 0, + dev_name(&pdev->dev), i2c); + if (ret < 0) + return ret; + + strscpy(i2c->adap.name, "Conexant Digicolor I2C adapter", + sizeof(i2c->adap.name)); + i2c->adap.owner = THIS_MODULE; + i2c->adap.algo = &dc_i2c_algorithm; + i2c->adap.dev.parent = &pdev->dev; + i2c->adap.dev.of_node = np; + i2c->adap.algo_data = i2c; + + ret = dc_i2c_init_hw(i2c); + if (ret) + return ret; + + ret = clk_prepare_enable(i2c->clk); + if (ret < 0) + return ret; + + ret = i2c_add_adapter(&i2c->adap); + if (ret < 0) { + clk_disable_unprepare(i2c->clk); + return ret; + } + + return 0; +} + +static void dc_i2c_remove(struct platform_device *pdev) +{ + struct dc_i2c *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adap); + clk_disable_unprepare(i2c->clk); +} + +static const struct of_device_id dc_i2c_match[] = { + { .compatible = "cnxt,cx92755-i2c" }, + { }, +}; +MODULE_DEVICE_TABLE(of, dc_i2c_match); + +static struct platform_driver dc_i2c_driver = { + .probe = dc_i2c_probe, + .remove_new = dc_i2c_remove, + .driver = { + .name = "digicolor-i2c", + .of_match_table = dc_i2c_match, + }, +}; +module_platform_driver(dc_i2c_driver); + +MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>"); +MODULE_DESCRIPTION("Conexant Digicolor I2C master driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-diolan-u2c.c b/drivers/i2c/busses/i2c-diolan-u2c.c new file mode 100644 index 000000000..b48b78889 --- /dev/null +++ b/drivers/i2c/busses/i2c-diolan-u2c.c @@ -0,0 +1,518 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for the Diolan u2c-12 USB-I2C adapter + * + * Copyright (c) 2010-2011 Ericsson AB + * + * Derived from: + * i2c-tiny-usb.c + * Copyright (C) 2006-2007 Till Harbaum (Till@Harbaum.org) + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/usb.h> +#include <linux/i2c.h> + +#define DRIVER_NAME "i2c-diolan-u2c" + +#define USB_VENDOR_ID_DIOLAN 0x0abf +#define USB_DEVICE_ID_DIOLAN_U2C 0x3370 + + +/* commands via USB, must match command ids in the firmware */ +#define CMD_I2C_READ 0x01 +#define CMD_I2C_WRITE 0x02 +#define CMD_I2C_SCAN 0x03 /* Returns list of detected devices */ +#define CMD_I2C_RELEASE_SDA 0x04 +#define CMD_I2C_RELEASE_SCL 0x05 +#define CMD_I2C_DROP_SDA 0x06 +#define CMD_I2C_DROP_SCL 0x07 +#define CMD_I2C_READ_SDA 0x08 +#define CMD_I2C_READ_SCL 0x09 +#define CMD_GET_FW_VERSION 0x0a +#define CMD_GET_SERIAL 0x0b +#define CMD_I2C_START 0x0c +#define CMD_I2C_STOP 0x0d +#define CMD_I2C_REPEATED_START 0x0e +#define CMD_I2C_PUT_BYTE 0x0f +#define CMD_I2C_GET_BYTE 0x10 +#define CMD_I2C_PUT_ACK 0x11 +#define CMD_I2C_GET_ACK 0x12 +#define CMD_I2C_PUT_BYTE_ACK 0x13 +#define CMD_I2C_GET_BYTE_ACK 0x14 +#define CMD_I2C_SET_SPEED 0x1b +#define CMD_I2C_GET_SPEED 0x1c +#define CMD_I2C_SET_CLK_SYNC 0x24 +#define CMD_I2C_GET_CLK_SYNC 0x25 +#define CMD_I2C_SET_CLK_SYNC_TO 0x26 +#define CMD_I2C_GET_CLK_SYNC_TO 0x27 + +#define RESP_OK 0x00 +#define RESP_FAILED 0x01 +#define RESP_BAD_MEMADDR 0x04 +#define RESP_DATA_ERR 0x05 +#define RESP_NOT_IMPLEMENTED 0x06 +#define RESP_NACK 0x07 +#define RESP_TIMEOUT 0x09 + +#define U2C_I2C_SPEED_FAST 0 /* 400 kHz */ +#define U2C_I2C_SPEED_STD 1 /* 100 kHz */ +#define U2C_I2C_SPEED_2KHZ 242 /* 2 kHz, minimum speed */ +#define U2C_I2C_SPEED(f) ((DIV_ROUND_UP(1000000, (f)) - 10) / 2 + 1) + +#define U2C_I2C_FREQ(s) (1000000 / (2 * (s - 1) + 10)) + +#define DIOLAN_USB_TIMEOUT 100 /* in ms */ +#define DIOLAN_SYNC_TIMEOUT 20 /* in ms */ + +#define DIOLAN_OUTBUF_LEN 128 +#define DIOLAN_FLUSH_LEN (DIOLAN_OUTBUF_LEN - 4) +#define DIOLAN_INBUF_LEN 256 /* Maximum supported receive length */ + +/* Structure to hold all of our device specific stuff */ +struct i2c_diolan_u2c { + u8 obuffer[DIOLAN_OUTBUF_LEN]; /* output buffer */ + u8 ibuffer[DIOLAN_INBUF_LEN]; /* input buffer */ + int ep_in, ep_out; /* Endpoints */ + struct usb_device *usb_dev; /* the usb device for this device */ + struct usb_interface *interface;/* the interface for this device */ + struct i2c_adapter adapter; /* i2c related things */ + int olen; /* Output buffer length */ + int ocount; /* Number of enqueued messages */ +}; + +static uint frequency = I2C_MAX_STANDARD_MODE_FREQ; /* I2C clock frequency in Hz */ + +module_param(frequency, uint, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(frequency, "I2C clock frequency in hertz"); + +/* usb layer */ + +/* Send command to device, and get response. */ +static int diolan_usb_transfer(struct i2c_diolan_u2c *dev) +{ + int ret = 0; + int actual; + int i; + + if (!dev->olen || !dev->ocount) + return -EINVAL; + + ret = usb_bulk_msg(dev->usb_dev, + usb_sndbulkpipe(dev->usb_dev, dev->ep_out), + dev->obuffer, dev->olen, &actual, + DIOLAN_USB_TIMEOUT); + if (!ret) { + for (i = 0; i < dev->ocount; i++) { + int tmpret; + + tmpret = usb_bulk_msg(dev->usb_dev, + usb_rcvbulkpipe(dev->usb_dev, + dev->ep_in), + dev->ibuffer, + sizeof(dev->ibuffer), &actual, + DIOLAN_USB_TIMEOUT); + /* + * Stop command processing if a previous command + * returned an error. + * Note that we still need to retrieve all messages. + */ + if (ret < 0) + continue; + ret = tmpret; + if (ret == 0 && actual > 0) { + switch (dev->ibuffer[actual - 1]) { + case RESP_NACK: + /* + * Return ENXIO if NACK was received as + * response to the address phase, + * EIO otherwise + */ + ret = i == 1 ? -ENXIO : -EIO; + break; + case RESP_TIMEOUT: + ret = -ETIMEDOUT; + break; + case RESP_OK: + /* strip off return code */ + ret = actual - 1; + break; + default: + ret = -EIO; + break; + } + } + } + } + dev->olen = 0; + dev->ocount = 0; + return ret; +} + +static int diolan_write_cmd(struct i2c_diolan_u2c *dev, bool flush) +{ + if (flush || dev->olen >= DIOLAN_FLUSH_LEN) + return diolan_usb_transfer(dev); + return 0; +} + +/* Send command (no data) */ +static int diolan_usb_cmd(struct i2c_diolan_u2c *dev, u8 command, bool flush) +{ + dev->obuffer[dev->olen++] = command; + dev->ocount++; + return diolan_write_cmd(dev, flush); +} + +/* Send command with one byte of data */ +static int diolan_usb_cmd_data(struct i2c_diolan_u2c *dev, u8 command, u8 data, + bool flush) +{ + dev->obuffer[dev->olen++] = command; + dev->obuffer[dev->olen++] = data; + dev->ocount++; + return diolan_write_cmd(dev, flush); +} + +/* Send command with two bytes of data */ +static int diolan_usb_cmd_data2(struct i2c_diolan_u2c *dev, u8 command, u8 d1, + u8 d2, bool flush) +{ + dev->obuffer[dev->olen++] = command; + dev->obuffer[dev->olen++] = d1; + dev->obuffer[dev->olen++] = d2; + dev->ocount++; + return diolan_write_cmd(dev, flush); +} + +/* + * Flush input queue. + * If we don't do this at startup and the controller has queued up + * messages which were not retrieved, it will stop responding + * at some point. + */ +static void diolan_flush_input(struct i2c_diolan_u2c *dev) +{ + int i; + + for (i = 0; i < 10; i++) { + int actual = 0; + int ret; + + ret = usb_bulk_msg(dev->usb_dev, + usb_rcvbulkpipe(dev->usb_dev, dev->ep_in), + dev->ibuffer, sizeof(dev->ibuffer), &actual, + DIOLAN_USB_TIMEOUT); + if (ret < 0 || actual == 0) + break; + } + if (i == 10) + dev_err(&dev->interface->dev, "Failed to flush input buffer\n"); +} + +static int diolan_i2c_start(struct i2c_diolan_u2c *dev) +{ + return diolan_usb_cmd(dev, CMD_I2C_START, false); +} + +static int diolan_i2c_repeated_start(struct i2c_diolan_u2c *dev) +{ + return diolan_usb_cmd(dev, CMD_I2C_REPEATED_START, false); +} + +static int diolan_i2c_stop(struct i2c_diolan_u2c *dev) +{ + return diolan_usb_cmd(dev, CMD_I2C_STOP, true); +} + +static int diolan_i2c_get_byte_ack(struct i2c_diolan_u2c *dev, bool ack, + u8 *byte) +{ + int ret; + + ret = diolan_usb_cmd_data(dev, CMD_I2C_GET_BYTE_ACK, ack, true); + if (ret > 0) + *byte = dev->ibuffer[0]; + else if (ret == 0) + ret = -EIO; + + return ret; +} + +static int diolan_i2c_put_byte_ack(struct i2c_diolan_u2c *dev, u8 byte) +{ + return diolan_usb_cmd_data(dev, CMD_I2C_PUT_BYTE_ACK, byte, false); +} + +static int diolan_set_speed(struct i2c_diolan_u2c *dev, u8 speed) +{ + return diolan_usb_cmd_data(dev, CMD_I2C_SET_SPEED, speed, true); +} + +/* Enable or disable clock synchronization (stretching) */ +static int diolan_set_clock_synch(struct i2c_diolan_u2c *dev, bool enable) +{ + return diolan_usb_cmd_data(dev, CMD_I2C_SET_CLK_SYNC, enable, true); +} + +/* Set clock synchronization timeout in ms */ +static int diolan_set_clock_synch_timeout(struct i2c_diolan_u2c *dev, int ms) +{ + int to_val = ms * 10; + + return diolan_usb_cmd_data2(dev, CMD_I2C_SET_CLK_SYNC_TO, + to_val & 0xff, (to_val >> 8) & 0xff, true); +} + +static void diolan_fw_version(struct i2c_diolan_u2c *dev) +{ + int ret; + + ret = diolan_usb_cmd(dev, CMD_GET_FW_VERSION, true); + if (ret >= 2) + dev_info(&dev->interface->dev, + "Diolan U2C firmware version %u.%u\n", + (unsigned int)dev->ibuffer[0], + (unsigned int)dev->ibuffer[1]); +} + +static void diolan_get_serial(struct i2c_diolan_u2c *dev) +{ + int ret; + u32 serial; + + ret = diolan_usb_cmd(dev, CMD_GET_SERIAL, true); + if (ret >= 4) { + serial = le32_to_cpu(*(u32 *)dev->ibuffer); + dev_info(&dev->interface->dev, + "Diolan U2C serial number %u\n", serial); + } +} + +static int diolan_init(struct i2c_diolan_u2c *dev) +{ + int speed, ret; + + if (frequency >= 2 * I2C_MAX_STANDARD_MODE_FREQ) { + speed = U2C_I2C_SPEED_FAST; + frequency = I2C_MAX_FAST_MODE_FREQ; + } else if (frequency >= I2C_MAX_STANDARD_MODE_FREQ || frequency == 0) { + speed = U2C_I2C_SPEED_STD; + frequency = I2C_MAX_STANDARD_MODE_FREQ; + } else { + speed = U2C_I2C_SPEED(frequency); + if (speed > U2C_I2C_SPEED_2KHZ) + speed = U2C_I2C_SPEED_2KHZ; + frequency = U2C_I2C_FREQ(speed); + } + + dev_info(&dev->interface->dev, + "Diolan U2C at USB bus %03d address %03d speed %d Hz\n", + dev->usb_dev->bus->busnum, dev->usb_dev->devnum, frequency); + + diolan_flush_input(dev); + diolan_fw_version(dev); + diolan_get_serial(dev); + + /* Set I2C speed */ + ret = diolan_set_speed(dev, speed); + if (ret < 0) + return ret; + + /* Configure I2C clock synchronization */ + ret = diolan_set_clock_synch(dev, speed != U2C_I2C_SPEED_FAST); + if (ret < 0) + return ret; + + if (speed != U2C_I2C_SPEED_FAST) + ret = diolan_set_clock_synch_timeout(dev, DIOLAN_SYNC_TIMEOUT); + + return ret; +} + +/* i2c layer */ + +static int diolan_usb_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, + int num) +{ + struct i2c_diolan_u2c *dev = i2c_get_adapdata(adapter); + struct i2c_msg *pmsg; + int i, j; + int ret, sret; + + ret = diolan_i2c_start(dev); + if (ret < 0) + return ret; + + for (i = 0; i < num; i++) { + pmsg = &msgs[i]; + if (i) { + ret = diolan_i2c_repeated_start(dev); + if (ret < 0) + goto abort; + } + ret = diolan_i2c_put_byte_ack(dev, + i2c_8bit_addr_from_msg(pmsg)); + if (ret < 0) + goto abort; + if (pmsg->flags & I2C_M_RD) { + for (j = 0; j < pmsg->len; j++) { + u8 byte; + bool ack = j < pmsg->len - 1; + + /* + * Don't send NACK if this is the first byte + * of a SMBUS_BLOCK message. + */ + if (j == 0 && (pmsg->flags & I2C_M_RECV_LEN)) + ack = true; + + ret = diolan_i2c_get_byte_ack(dev, ack, &byte); + if (ret < 0) + goto abort; + /* + * Adjust count if first received byte is length + */ + if (j == 0 && (pmsg->flags & I2C_M_RECV_LEN)) { + if (byte == 0 + || byte > I2C_SMBUS_BLOCK_MAX) { + ret = -EPROTO; + goto abort; + } + pmsg->len += byte; + } + pmsg->buf[j] = byte; + } + } else { + for (j = 0; j < pmsg->len; j++) { + ret = diolan_i2c_put_byte_ack(dev, + pmsg->buf[j]); + if (ret < 0) + goto abort; + } + } + } + ret = num; +abort: + sret = diolan_i2c_stop(dev); + if (sret < 0 && ret >= 0) + ret = sret; + return ret; +} + +/* + * Return list of supported functionality. + */ +static u32 diolan_usb_func(struct i2c_adapter *a) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | + I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL; +} + +static const struct i2c_algorithm diolan_usb_algorithm = { + .master_xfer = diolan_usb_xfer, + .functionality = diolan_usb_func, +}; + +/* device layer */ + +static const struct usb_device_id diolan_u2c_table[] = { + { USB_DEVICE(USB_VENDOR_ID_DIOLAN, USB_DEVICE_ID_DIOLAN_U2C) }, + { } +}; + +MODULE_DEVICE_TABLE(usb, diolan_u2c_table); + +static void diolan_u2c_free(struct i2c_diolan_u2c *dev) +{ + usb_put_dev(dev->usb_dev); + kfree(dev); +} + +static int diolan_u2c_probe(struct usb_interface *interface, + const struct usb_device_id *id) +{ + struct usb_host_interface *hostif = interface->cur_altsetting; + struct i2c_diolan_u2c *dev; + int ret; + + if (hostif->desc.bInterfaceNumber != 0 + || hostif->desc.bNumEndpoints < 2) + return -ENODEV; + + /* allocate memory for our device state and initialize it */ + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (dev == NULL) { + ret = -ENOMEM; + goto error; + } + dev->ep_out = hostif->endpoint[0].desc.bEndpointAddress; + dev->ep_in = hostif->endpoint[1].desc.bEndpointAddress; + + dev->usb_dev = usb_get_dev(interface_to_usbdev(interface)); + dev->interface = interface; + + /* save our data pointer in this interface device */ + usb_set_intfdata(interface, dev); + + /* setup i2c adapter description */ + dev->adapter.owner = THIS_MODULE; + dev->adapter.class = I2C_CLASS_HWMON; + dev->adapter.algo = &diolan_usb_algorithm; + i2c_set_adapdata(&dev->adapter, dev); + snprintf(dev->adapter.name, sizeof(dev->adapter.name), + DRIVER_NAME " at bus %03d device %03d", + dev->usb_dev->bus->busnum, dev->usb_dev->devnum); + + dev->adapter.dev.parent = &dev->interface->dev; + + /* initialize diolan i2c interface */ + ret = diolan_init(dev); + if (ret < 0) { + dev_err(&interface->dev, "failed to initialize adapter\n"); + goto error_free; + } + + /* and finally attach to i2c layer */ + ret = i2c_add_adapter(&dev->adapter); + if (ret < 0) + goto error_free; + + dev_dbg(&interface->dev, "connected " DRIVER_NAME "\n"); + + return 0; + +error_free: + usb_set_intfdata(interface, NULL); + diolan_u2c_free(dev); +error: + return ret; +} + +static void diolan_u2c_disconnect(struct usb_interface *interface) +{ + struct i2c_diolan_u2c *dev = usb_get_intfdata(interface); + + i2c_del_adapter(&dev->adapter); + usb_set_intfdata(interface, NULL); + diolan_u2c_free(dev); + + dev_dbg(&interface->dev, "disconnected\n"); +} + +static struct usb_driver diolan_u2c_driver = { + .name = DRIVER_NAME, + .probe = diolan_u2c_probe, + .disconnect = diolan_u2c_disconnect, + .id_table = diolan_u2c_table, +}; + +module_usb_driver(diolan_u2c_driver); + +MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>"); +MODULE_DESCRIPTION(DRIVER_NAME " driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-dln2.c b/drivers/i2c/busses/i2c-dln2.c new file mode 100644 index 000000000..631109c7a --- /dev/null +++ b/drivers/i2c/busses/i2c-dln2.c @@ -0,0 +1,256 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for the Diolan DLN-2 USB-I2C adapter + * + * Copyright (c) 2014 Intel Corporation + * + * Derived from: + * i2c-diolan-u2c.c + * Copyright (c) 2010-2011 Ericsson AB + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/i2c.h> +#include <linux/platform_device.h> +#include <linux/mfd/dln2.h> +#include <linux/acpi.h> + +#define DLN2_I2C_MODULE_ID 0x03 +#define DLN2_I2C_CMD(cmd) DLN2_CMD(cmd, DLN2_I2C_MODULE_ID) + +/* I2C commands */ +#define DLN2_I2C_GET_PORT_COUNT DLN2_I2C_CMD(0x00) +#define DLN2_I2C_ENABLE DLN2_I2C_CMD(0x01) +#define DLN2_I2C_DISABLE DLN2_I2C_CMD(0x02) +#define DLN2_I2C_IS_ENABLED DLN2_I2C_CMD(0x03) +#define DLN2_I2C_WRITE DLN2_I2C_CMD(0x06) +#define DLN2_I2C_READ DLN2_I2C_CMD(0x07) +#define DLN2_I2C_SCAN_DEVICES DLN2_I2C_CMD(0x08) +#define DLN2_I2C_PULLUP_ENABLE DLN2_I2C_CMD(0x09) +#define DLN2_I2C_PULLUP_DISABLE DLN2_I2C_CMD(0x0A) +#define DLN2_I2C_PULLUP_IS_ENABLED DLN2_I2C_CMD(0x0B) +#define DLN2_I2C_TRANSFER DLN2_I2C_CMD(0x0C) +#define DLN2_I2C_SET_MAX_REPLY_COUNT DLN2_I2C_CMD(0x0D) +#define DLN2_I2C_GET_MAX_REPLY_COUNT DLN2_I2C_CMD(0x0E) + +#define DLN2_I2C_MAX_XFER_SIZE 256 +#define DLN2_I2C_BUF_SIZE (DLN2_I2C_MAX_XFER_SIZE + 16) + +struct dln2_i2c { + struct platform_device *pdev; + struct i2c_adapter adapter; + u8 port; + /* + * Buffer to hold the packet for read or write transfers. One is enough + * since we can't have multiple transfers in parallel on the i2c bus. + */ + void *buf; +}; + +static int dln2_i2c_enable(struct dln2_i2c *dln2, bool enable) +{ + u16 cmd; + struct { + u8 port; + } tx; + + tx.port = dln2->port; + + if (enable) + cmd = DLN2_I2C_ENABLE; + else + cmd = DLN2_I2C_DISABLE; + + return dln2_transfer_tx(dln2->pdev, cmd, &tx, sizeof(tx)); +} + +static int dln2_i2c_write(struct dln2_i2c *dln2, u8 addr, + u8 *data, u16 data_len) +{ + int ret; + struct { + u8 port; + u8 addr; + u8 mem_addr_len; + __le32 mem_addr; + __le16 buf_len; + u8 buf[DLN2_I2C_MAX_XFER_SIZE]; + } __packed *tx = dln2->buf; + unsigned len; + + BUILD_BUG_ON(sizeof(*tx) > DLN2_I2C_BUF_SIZE); + + tx->port = dln2->port; + tx->addr = addr; + tx->mem_addr_len = 0; + tx->mem_addr = 0; + tx->buf_len = cpu_to_le16(data_len); + memcpy(tx->buf, data, data_len); + + len = sizeof(*tx) + data_len - DLN2_I2C_MAX_XFER_SIZE; + ret = dln2_transfer_tx(dln2->pdev, DLN2_I2C_WRITE, tx, len); + if (ret < 0) + return ret; + + return data_len; +} + +static int dln2_i2c_read(struct dln2_i2c *dln2, u16 addr, u8 *data, + u16 data_len) +{ + int ret; + struct { + u8 port; + u8 addr; + u8 mem_addr_len; + __le32 mem_addr; + __le16 buf_len; + } __packed tx; + struct { + __le16 buf_len; + u8 buf[DLN2_I2C_MAX_XFER_SIZE]; + } __packed *rx = dln2->buf; + unsigned rx_len = sizeof(*rx); + + BUILD_BUG_ON(sizeof(*rx) > DLN2_I2C_BUF_SIZE); + + tx.port = dln2->port; + tx.addr = addr; + tx.mem_addr_len = 0; + tx.mem_addr = 0; + tx.buf_len = cpu_to_le16(data_len); + + ret = dln2_transfer(dln2->pdev, DLN2_I2C_READ, &tx, sizeof(tx), + rx, &rx_len); + if (ret < 0) + return ret; + if (rx_len < sizeof(rx->buf_len) + data_len) + return -EPROTO; + if (le16_to_cpu(rx->buf_len) != data_len) + return -EPROTO; + + memcpy(data, rx->buf, data_len); + + return data_len; +} + +static int dln2_i2c_xfer(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num) +{ + struct dln2_i2c *dln2 = i2c_get_adapdata(adapter); + struct i2c_msg *pmsg; + int i; + + for (i = 0; i < num; i++) { + int ret; + + pmsg = &msgs[i]; + + if (pmsg->flags & I2C_M_RD) { + ret = dln2_i2c_read(dln2, pmsg->addr, pmsg->buf, + pmsg->len); + if (ret < 0) + return ret; + + pmsg->len = ret; + } else { + ret = dln2_i2c_write(dln2, pmsg->addr, pmsg->buf, + pmsg->len); + if (ret != pmsg->len) + return -EPROTO; + } + } + + return num; +} + +static u32 dln2_i2c_func(struct i2c_adapter *a) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL | + I2C_FUNC_SMBUS_I2C_BLOCK; +} + +static const struct i2c_algorithm dln2_i2c_usb_algorithm = { + .master_xfer = dln2_i2c_xfer, + .functionality = dln2_i2c_func, +}; + +static const struct i2c_adapter_quirks dln2_i2c_quirks = { + .max_read_len = DLN2_I2C_MAX_XFER_SIZE, + .max_write_len = DLN2_I2C_MAX_XFER_SIZE, +}; + +static int dln2_i2c_probe(struct platform_device *pdev) +{ + int ret; + struct dln2_i2c *dln2; + struct device *dev = &pdev->dev; + struct dln2_platform_data *pdata = dev_get_platdata(&pdev->dev); + + dln2 = devm_kzalloc(dev, sizeof(*dln2), GFP_KERNEL); + if (!dln2) + return -ENOMEM; + + dln2->buf = devm_kmalloc(dev, DLN2_I2C_BUF_SIZE, GFP_KERNEL); + if (!dln2->buf) + return -ENOMEM; + + dln2->pdev = pdev; + dln2->port = pdata->port; + + /* setup i2c adapter description */ + dln2->adapter.owner = THIS_MODULE; + dln2->adapter.class = I2C_CLASS_HWMON; + dln2->adapter.algo = &dln2_i2c_usb_algorithm; + dln2->adapter.quirks = &dln2_i2c_quirks; + dln2->adapter.dev.parent = dev; + ACPI_COMPANION_SET(&dln2->adapter.dev, ACPI_COMPANION(&pdev->dev)); + dln2->adapter.dev.of_node = dev->of_node; + i2c_set_adapdata(&dln2->adapter, dln2); + snprintf(dln2->adapter.name, sizeof(dln2->adapter.name), "%s-%s-%d", + "dln2-i2c", dev_name(pdev->dev.parent), dln2->port); + + platform_set_drvdata(pdev, dln2); + + /* initialize the i2c interface */ + ret = dln2_i2c_enable(dln2, true); + if (ret < 0) + return dev_err_probe(dev, ret, "failed to initialize adapter\n"); + + /* and finally attach to i2c layer */ + ret = i2c_add_adapter(&dln2->adapter); + if (ret < 0) + goto out_disable; + + return 0; + +out_disable: + dln2_i2c_enable(dln2, false); + + return ret; +} + +static void dln2_i2c_remove(struct platform_device *pdev) +{ + struct dln2_i2c *dln2 = platform_get_drvdata(pdev); + + i2c_del_adapter(&dln2->adapter); + dln2_i2c_enable(dln2, false); +} + +static struct platform_driver dln2_i2c_driver = { + .driver.name = "dln2-i2c", + .probe = dln2_i2c_probe, + .remove_new = dln2_i2c_remove, +}; + +module_platform_driver(dln2_i2c_driver); + +MODULE_AUTHOR("Laurentiu Palcu <laurentiu.palcu@intel.com>"); +MODULE_DESCRIPTION("Driver for the Diolan DLN2 I2C master interface"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:dln2-i2c"); diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c new file mode 100644 index 000000000..4914bfbee --- /dev/null +++ b/drivers/i2c/busses/i2c-eg20t.c @@ -0,0 +1,907 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd. + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/fs.h> +#include <linux/io.h> +#include <linux/types.h> +#include <linux/interrupt.h> +#include <linux/jiffies.h> +#include <linux/pci.h> +#include <linux/mutex.h> +#include <linux/ktime.h> +#include <linux/slab.h> + +#define PCH_EVENT_SET 0 /* I2C Interrupt Event Set Status */ +#define PCH_EVENT_NONE 1 /* I2C Interrupt Event Clear Status */ +#define PCH_MAX_CLK 100000 /* Maximum Clock speed in MHz */ +#define PCH_BUFFER_MODE_ENABLE 0x0002 /* flag for Buffer mode enable */ +#define PCH_EEPROM_SW_RST_MODE_ENABLE 0x0008 /* EEPROM SW RST enable flag */ + +#define PCH_I2CSADR 0x00 /* I2C slave address register */ +#define PCH_I2CCTL 0x04 /* I2C control register */ +#define PCH_I2CSR 0x08 /* I2C status register */ +#define PCH_I2CDR 0x0C /* I2C data register */ +#define PCH_I2CMON 0x10 /* I2C bus monitor register */ +#define PCH_I2CBC 0x14 /* I2C bus transfer rate setup counter */ +#define PCH_I2CMOD 0x18 /* I2C mode register */ +#define PCH_I2CBUFSLV 0x1C /* I2C buffer mode slave address register */ +#define PCH_I2CBUFSUB 0x20 /* I2C buffer mode subaddress register */ +#define PCH_I2CBUFFOR 0x24 /* I2C buffer mode format register */ +#define PCH_I2CBUFCTL 0x28 /* I2C buffer mode control register */ +#define PCH_I2CBUFMSK 0x2C /* I2C buffer mode interrupt mask register */ +#define PCH_I2CBUFSTA 0x30 /* I2C buffer mode status register */ +#define PCH_I2CBUFLEV 0x34 /* I2C buffer mode level register */ +#define PCH_I2CESRFOR 0x38 /* EEPROM software reset mode format register */ +#define PCH_I2CESRCTL 0x3C /* EEPROM software reset mode ctrl register */ +#define PCH_I2CESRMSK 0x40 /* EEPROM software reset mode */ +#define PCH_I2CESRSTA 0x44 /* EEPROM software reset mode status register */ +#define PCH_I2CTMR 0x48 /* I2C timer register */ +#define PCH_I2CSRST 0xFC /* I2C reset register */ +#define PCH_I2CNF 0xF8 /* I2C noise filter register */ + +#define BUS_IDLE_TIMEOUT 20 +#define PCH_I2CCTL_I2CMEN 0x0080 +#define TEN_BIT_ADDR_DEFAULT 0xF000 +#define TEN_BIT_ADDR_MASK 0xF0 +#define PCH_START 0x0020 +#define PCH_RESTART 0x0004 +#define PCH_ESR_START 0x0001 +#define PCH_BUFF_START 0x1 +#define PCH_REPSTART 0x0004 +#define PCH_ACK 0x0008 +#define PCH_GETACK 0x0001 +#define CLR_REG 0x0 +#define I2C_RD 0x1 +#define I2CMCF_BIT 0x0080 +#define I2CMIF_BIT 0x0002 +#define I2CMAL_BIT 0x0010 +#define I2CBMFI_BIT 0x0001 +#define I2CBMAL_BIT 0x0002 +#define I2CBMNA_BIT 0x0004 +#define I2CBMTO_BIT 0x0008 +#define I2CBMIS_BIT 0x0010 +#define I2CESRFI_BIT 0X0001 +#define I2CESRTO_BIT 0x0002 +#define I2CESRFIIE_BIT 0x1 +#define I2CESRTOIE_BIT 0x2 +#define I2CBMDZ_BIT 0x0040 +#define I2CBMAG_BIT 0x0020 +#define I2CMBB_BIT 0x0020 +#define BUFFER_MODE_MASK (I2CBMFI_BIT | I2CBMAL_BIT | I2CBMNA_BIT | \ + I2CBMTO_BIT | I2CBMIS_BIT) +#define I2C_ADDR_MSK 0xFF +#define I2C_MSB_2B_MSK 0x300 +#define FAST_MODE_CLK 400 +#define FAST_MODE_EN 0x0001 +#define SUB_ADDR_LEN_MAX 4 +#define BUF_LEN_MAX 32 +#define PCH_BUFFER_MODE 0x1 +#define EEPROM_SW_RST_MODE 0x0002 +#define NORMAL_INTR_ENBL 0x0300 +#define EEPROM_RST_INTR_ENBL (I2CESRFIIE_BIT | I2CESRTOIE_BIT) +#define EEPROM_RST_INTR_DISBL 0x0 +#define BUFFER_MODE_INTR_ENBL 0x001F +#define BUFFER_MODE_INTR_DISBL 0x0 +#define NORMAL_MODE 0x0 +#define BUFFER_MODE 0x1 +#define EEPROM_SR_MODE 0x2 +#define I2C_TX_MODE 0x0010 +#define PCH_BUF_TX 0xFFF7 +#define PCH_BUF_RD 0x0008 +#define I2C_ERROR_MASK (I2CESRTO_EVENT | I2CBMIS_EVENT | I2CBMTO_EVENT | \ + I2CBMNA_EVENT | I2CBMAL_EVENT | I2CMAL_EVENT) +#define I2CMAL_EVENT 0x0001 +#define I2CMCF_EVENT 0x0002 +#define I2CBMFI_EVENT 0x0004 +#define I2CBMAL_EVENT 0x0008 +#define I2CBMNA_EVENT 0x0010 +#define I2CBMTO_EVENT 0x0020 +#define I2CBMIS_EVENT 0x0040 +#define I2CESRFI_EVENT 0x0080 +#define I2CESRTO_EVENT 0x0100 +#define PCI_DEVICE_ID_PCH_I2C 0x8817 + +#define pch_dbg(adap, fmt, arg...) \ + dev_dbg(adap->pch_adapter.dev.parent, "%s :" fmt, __func__, ##arg) + +#define pch_err(adap, fmt, arg...) \ + dev_err(adap->pch_adapter.dev.parent, "%s :" fmt, __func__, ##arg) + +#define pch_pci_err(pdev, fmt, arg...) \ + dev_err(&pdev->dev, "%s :" fmt, __func__, ##arg) + +#define pch_pci_dbg(pdev, fmt, arg...) \ + dev_dbg(&pdev->dev, "%s :" fmt, __func__, ##arg) + +/* +Set the number of I2C instance max +Intel EG20T PCH : 1ch +LAPIS Semiconductor ML7213 IOH : 2ch +LAPIS Semiconductor ML7831 IOH : 1ch +*/ +#define PCH_I2C_MAX_DEV 2 + +/** + * struct i2c_algo_pch_data - for I2C driver functionalities + * @pch_adapter: stores the reference to i2c_adapter structure + * @p_adapter_info: stores the reference to adapter_info structure + * @pch_base_address: specifies the remapped base address + * @pch_buff_mode_en: specifies if buffer mode is enabled + * @pch_event_flag: specifies occurrence of interrupt events + * @pch_i2c_xfer_in_progress: specifies whether the transfer is completed + */ +struct i2c_algo_pch_data { + struct i2c_adapter pch_adapter; + struct adapter_info *p_adapter_info; + void __iomem *pch_base_address; + int pch_buff_mode_en; + u32 pch_event_flag; + bool pch_i2c_xfer_in_progress; +}; + +/** + * struct adapter_info - This structure holds the adapter information for the + * PCH i2c controller + * @pch_data: stores a list of i2c_algo_pch_data + * @pch_i2c_suspended: specifies whether the system is suspended or not + * perhaps with more lines and words. + * @ch_num: specifies the number of i2c instance + * + * pch_data has as many elements as maximum I2C channels + */ +struct adapter_info { + struct i2c_algo_pch_data pch_data[PCH_I2C_MAX_DEV]; + bool pch_i2c_suspended; + int ch_num; +}; + + +static int pch_i2c_speed = 100; /* I2C bus speed in Kbps */ +static int pch_clk = 50000; /* specifies I2C clock speed in KHz */ +static wait_queue_head_t pch_event; +static DEFINE_MUTEX(pch_mutex); + +/* Definition for ML7213 by LAPIS Semiconductor */ +#define PCI_DEVICE_ID_ML7213_I2C 0x802D +#define PCI_DEVICE_ID_ML7223_I2C 0x8010 +#define PCI_DEVICE_ID_ML7831_I2C 0x8817 + +static const struct pci_device_id pch_pcidev_id[] = { + { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_PCH_I2C), 1, }, + { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_I2C), 2, }, + { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_I2C), 1, }, + { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_I2C), 1, }, + {0,} +}; +MODULE_DEVICE_TABLE(pci, pch_pcidev_id); + +static irqreturn_t pch_i2c_handler(int irq, void *pData); + +static inline void pch_setbit(void __iomem *addr, u32 offset, u32 bitmask) +{ + u32 val; + val = ioread32(addr + offset); + val |= bitmask; + iowrite32(val, addr + offset); +} + +static inline void pch_clrbit(void __iomem *addr, u32 offset, u32 bitmask) +{ + u32 val; + val = ioread32(addr + offset); + val &= (~bitmask); + iowrite32(val, addr + offset); +} + +/** + * pch_i2c_init() - hardware initialization of I2C module + * @adap: Pointer to struct i2c_algo_pch_data. + */ +static void pch_i2c_init(struct i2c_algo_pch_data *adap) +{ + void __iomem *p = adap->pch_base_address; + u32 pch_i2cbc; + u32 pch_i2ctmr; + u32 reg_value; + + /* reset I2C controller */ + iowrite32(0x01, p + PCH_I2CSRST); + msleep(20); + iowrite32(0x0, p + PCH_I2CSRST); + + /* Initialize I2C registers */ + iowrite32(0x21, p + PCH_I2CNF); + + pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_I2CCTL_I2CMEN); + + if (pch_i2c_speed != 400) + pch_i2c_speed = 100; + + reg_value = PCH_I2CCTL_I2CMEN; + if (pch_i2c_speed == FAST_MODE_CLK) { + reg_value |= FAST_MODE_EN; + pch_dbg(adap, "Fast mode enabled\n"); + } + + if (pch_clk > PCH_MAX_CLK) + pch_clk = 62500; + + pch_i2cbc = (pch_clk + (pch_i2c_speed * 4)) / (pch_i2c_speed * 8); + /* Set transfer speed in I2CBC */ + iowrite32(pch_i2cbc, p + PCH_I2CBC); + + pch_i2ctmr = (pch_clk) / 8; + iowrite32(pch_i2ctmr, p + PCH_I2CTMR); + + reg_value |= NORMAL_INTR_ENBL; /* Enable interrupts in normal mode */ + iowrite32(reg_value, p + PCH_I2CCTL); + + pch_dbg(adap, + "I2CCTL=%x pch_i2cbc=%x pch_i2ctmr=%x Enable interrupts\n", + ioread32(p + PCH_I2CCTL), pch_i2cbc, pch_i2ctmr); + + init_waitqueue_head(&pch_event); +} + +/** + * pch_i2c_wait_for_bus_idle() - check the status of bus. + * @adap: Pointer to struct i2c_algo_pch_data. + * @timeout: waiting time counter (ms). + */ +static s32 pch_i2c_wait_for_bus_idle(struct i2c_algo_pch_data *adap, + s32 timeout) +{ + void __iomem *p = adap->pch_base_address; + int schedule = 0; + unsigned long end = jiffies + msecs_to_jiffies(timeout); + + while (ioread32(p + PCH_I2CSR) & I2CMBB_BIT) { + if (time_after(jiffies, end)) { + pch_dbg(adap, "I2CSR = %x\n", ioread32(p + PCH_I2CSR)); + pch_err(adap, "%s: Timeout Error.return%d\n", + __func__, -ETIME); + pch_i2c_init(adap); + + return -ETIME; + } + + if (!schedule) + /* Retry after some usecs */ + udelay(5); + else + /* Wait a bit more without consuming CPU */ + usleep_range(20, 1000); + + schedule = 1; + } + + return 0; +} + +/** + * pch_i2c_start() - Generate I2C start condition in normal mode. + * @adap: Pointer to struct i2c_algo_pch_data. + * + * Generate I2C start condition in normal mode by setting I2CCTL.I2CMSTA to 1. + */ +static void pch_i2c_start(struct i2c_algo_pch_data *adap) +{ + void __iomem *p = adap->pch_base_address; + pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); + pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_START); +} + +/** + * pch_i2c_stop() - generate stop condition in normal mode. + * @adap: Pointer to struct i2c_algo_pch_data. + */ +static void pch_i2c_stop(struct i2c_algo_pch_data *adap) +{ + void __iomem *p = adap->pch_base_address; + pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); + /* clear the start bit */ + pch_clrbit(adap->pch_base_address, PCH_I2CCTL, PCH_START); +} + +static int pch_i2c_wait_for_check_xfer(struct i2c_algo_pch_data *adap) +{ + long ret; + void __iomem *p = adap->pch_base_address; + + ret = wait_event_timeout(pch_event, + (adap->pch_event_flag != 0), msecs_to_jiffies(1000)); + if (!ret) { + pch_err(adap, "%s:wait-event timeout\n", __func__); + adap->pch_event_flag = 0; + pch_i2c_stop(adap); + pch_i2c_init(adap); + return -ETIMEDOUT; + } + + if (adap->pch_event_flag & I2C_ERROR_MASK) { + pch_err(adap, "Lost Arbitration\n"); + adap->pch_event_flag = 0; + pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMAL_BIT); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT); + pch_i2c_init(adap); + return -EAGAIN; + } + + adap->pch_event_flag = 0; + + if (ioread32(p + PCH_I2CSR) & PCH_GETACK) { + pch_dbg(adap, "Receive NACK for slave address setting\n"); + return -ENXIO; + } + + return 0; +} + +/** + * pch_i2c_repstart() - generate repeated start condition in normal mode + * @adap: Pointer to struct i2c_algo_pch_data. + */ +static void pch_i2c_repstart(struct i2c_algo_pch_data *adap) +{ + void __iomem *p = adap->pch_base_address; + pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); + pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_REPSTART); +} + +/** + * pch_i2c_writebytes() - write data to I2C bus in normal mode + * @i2c_adap: Pointer to the struct i2c_adapter. + * @msgs: Pointer to the i2c message structure. + * @last: specifies whether last message or not. + * In the case of compound mode it will be 1 for last message, + * otherwise 0. + * @first: specifies whether first message or not. + * 1 for first message otherwise 0. + */ +static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap, + struct i2c_msg *msgs, u32 last, u32 first) +{ + struct i2c_algo_pch_data *adap = i2c_adap->algo_data; + u8 *buf; + u32 length; + u32 addr; + u32 addr_2_msb; + u32 addr_8_lsb; + s32 wrcount; + s32 rtn; + void __iomem *p = adap->pch_base_address; + + length = msgs->len; + buf = msgs->buf; + addr = msgs->addr; + + /* enable master tx */ + pch_setbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE); + + pch_dbg(adap, "I2CCTL = %x msgs->len = %d\n", ioread32(p + PCH_I2CCTL), + length); + + if (first) { + if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME) + return -ETIME; + } + + if (msgs->flags & I2C_M_TEN) { + addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7) & 0x06; + iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR); + if (first) + pch_i2c_start(adap); + + rtn = pch_i2c_wait_for_check_xfer(adap); + if (rtn) + return rtn; + + addr_8_lsb = (addr & I2C_ADDR_MSK); + iowrite32(addr_8_lsb, p + PCH_I2CDR); + } else { + /* set 7 bit slave address and R/W bit as 0 */ + iowrite32(i2c_8bit_addr_from_msg(msgs), p + PCH_I2CDR); + if (first) + pch_i2c_start(adap); + } + + rtn = pch_i2c_wait_for_check_xfer(adap); + if (rtn) + return rtn; + + for (wrcount = 0; wrcount < length; ++wrcount) { + /* write buffer value to I2C data register */ + iowrite32(buf[wrcount], p + PCH_I2CDR); + pch_dbg(adap, "writing %x to Data register\n", buf[wrcount]); + + rtn = pch_i2c_wait_for_check_xfer(adap); + if (rtn) + return rtn; + + pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMCF_BIT); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT); + } + + /* check if this is the last message */ + if (last) + pch_i2c_stop(adap); + else + pch_i2c_repstart(adap); + + pch_dbg(adap, "return=%d\n", wrcount); + + return wrcount; +} + +/** + * pch_i2c_sendack() - send ACK + * @adap: Pointer to struct i2c_algo_pch_data. + */ +static void pch_i2c_sendack(struct i2c_algo_pch_data *adap) +{ + void __iomem *p = adap->pch_base_address; + pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); + pch_clrbit(adap->pch_base_address, PCH_I2CCTL, PCH_ACK); +} + +/** + * pch_i2c_sendnack() - send NACK + * @adap: Pointer to struct i2c_algo_pch_data. + */ +static void pch_i2c_sendnack(struct i2c_algo_pch_data *adap) +{ + void __iomem *p = adap->pch_base_address; + pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); + pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_ACK); +} + +/** + * pch_i2c_restart() - Generate I2C restart condition in normal mode. + * @adap: Pointer to struct i2c_algo_pch_data. + * + * Generate I2C restart condition in normal mode by setting I2CCTL.I2CRSTA. + */ +static void pch_i2c_restart(struct i2c_algo_pch_data *adap) +{ + void __iomem *p = adap->pch_base_address; + pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); + pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_RESTART); +} + +/** + * pch_i2c_readbytes() - read data from I2C bus in normal mode. + * @i2c_adap: Pointer to the struct i2c_adapter. + * @msgs: Pointer to i2c_msg structure. + * @last: specifies whether last message or not. + * @first: specifies whether first message or not. + */ +static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, + u32 last, u32 first) +{ + struct i2c_algo_pch_data *adap = i2c_adap->algo_data; + + u8 *buf; + u32 count; + u32 length; + u32 addr; + u32 addr_2_msb; + u32 addr_8_lsb; + void __iomem *p = adap->pch_base_address; + s32 rtn; + + length = msgs->len; + buf = msgs->buf; + addr = msgs->addr; + + /* enable master reception */ + pch_clrbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE); + + if (first) { + if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME) + return -ETIME; + } + + if (msgs->flags & I2C_M_TEN) { + addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7); + iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR); + if (first) + pch_i2c_start(adap); + + rtn = pch_i2c_wait_for_check_xfer(adap); + if (rtn) + return rtn; + + addr_8_lsb = (addr & I2C_ADDR_MSK); + iowrite32(addr_8_lsb, p + PCH_I2CDR); + + pch_i2c_restart(adap); + + rtn = pch_i2c_wait_for_check_xfer(adap); + if (rtn) + return rtn; + + addr_2_msb |= I2C_RD; + iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR); + } else { + /* 7 address bits + R/W bit */ + iowrite32(i2c_8bit_addr_from_msg(msgs), p + PCH_I2CDR); + } + + /* check if it is the first message */ + if (first) + pch_i2c_start(adap); + + rtn = pch_i2c_wait_for_check_xfer(adap); + if (rtn) + return rtn; + + if (length == 0) { + pch_i2c_stop(adap); + ioread32(p + PCH_I2CDR); /* Dummy read needs */ + + count = length; + } else { + int read_index; + int loop; + pch_i2c_sendack(adap); + + /* Dummy read */ + for (loop = 1, read_index = 0; loop < length; loop++) { + buf[read_index] = ioread32(p + PCH_I2CDR); + + if (loop != 1) + read_index++; + + rtn = pch_i2c_wait_for_check_xfer(adap); + if (rtn) + return rtn; + } /* end for */ + + pch_i2c_sendnack(adap); + + buf[read_index] = ioread32(p + PCH_I2CDR); /* Read final - 1 */ + + if (length != 1) + read_index++; + + rtn = pch_i2c_wait_for_check_xfer(adap); + if (rtn) + return rtn; + + if (last) + pch_i2c_stop(adap); + else + pch_i2c_repstart(adap); + + buf[read_index++] = ioread32(p + PCH_I2CDR); /* Read Final */ + count = read_index; + } + + return count; +} + +/** + * pch_i2c_cb() - Interrupt handler Call back function + * @adap: Pointer to struct i2c_algo_pch_data. + */ +static void pch_i2c_cb(struct i2c_algo_pch_data *adap) +{ + u32 sts; + void __iomem *p = adap->pch_base_address; + + sts = ioread32(p + PCH_I2CSR); + sts &= (I2CMAL_BIT | I2CMCF_BIT | I2CMIF_BIT); + if (sts & I2CMAL_BIT) + adap->pch_event_flag |= I2CMAL_EVENT; + + if (sts & I2CMCF_BIT) + adap->pch_event_flag |= I2CMCF_EVENT; + + /* clear the applicable bits */ + pch_clrbit(adap->pch_base_address, PCH_I2CSR, sts); + + pch_dbg(adap, "PCH_I2CSR = %x\n", ioread32(p + PCH_I2CSR)); + + wake_up(&pch_event); +} + +/** + * pch_i2c_handler() - interrupt handler for the PCH I2C controller + * @irq: irq number. + * @pData: cookie passed back to the handler function. + */ +static irqreturn_t pch_i2c_handler(int irq, void *pData) +{ + u32 reg_val; + int flag; + int i; + struct adapter_info *adap_info = pData; + void __iomem *p; + u32 mode; + + for (i = 0, flag = 0; i < adap_info->ch_num; i++) { + p = adap_info->pch_data[i].pch_base_address; + mode = ioread32(p + PCH_I2CMOD); + mode &= BUFFER_MODE | EEPROM_SR_MODE; + if (mode != NORMAL_MODE) { + pch_err(adap_info->pch_data, + "I2C-%d mode(%d) is not supported\n", mode, i); + continue; + } + reg_val = ioread32(p + PCH_I2CSR); + if (reg_val & (I2CMAL_BIT | I2CMCF_BIT | I2CMIF_BIT)) { + pch_i2c_cb(&adap_info->pch_data[i]); + flag = 1; + } + } + + return flag ? IRQ_HANDLED : IRQ_NONE; +} + +/** + * pch_i2c_xfer() - Reading adnd writing data through I2C bus + * @i2c_adap: Pointer to the struct i2c_adapter. + * @msgs: Pointer to i2c_msg structure. + * @num: number of messages. + */ +static s32 pch_i2c_xfer(struct i2c_adapter *i2c_adap, + struct i2c_msg *msgs, s32 num) +{ + struct i2c_msg *pmsg; + u32 i = 0; + u32 status; + s32 ret; + + struct i2c_algo_pch_data *adap = i2c_adap->algo_data; + + ret = mutex_lock_interruptible(&pch_mutex); + if (ret) + return ret; + + if (adap->p_adapter_info->pch_i2c_suspended) { + mutex_unlock(&pch_mutex); + return -EBUSY; + } + + pch_dbg(adap, "adap->p_adapter_info->pch_i2c_suspended is %d\n", + adap->p_adapter_info->pch_i2c_suspended); + /* transfer not completed */ + adap->pch_i2c_xfer_in_progress = true; + + for (i = 0; i < num && ret >= 0; i++) { + pmsg = &msgs[i]; + pmsg->flags |= adap->pch_buff_mode_en; + status = pmsg->flags; + pch_dbg(adap, + "After invoking I2C_MODE_SEL :flag= 0x%x\n", status); + + if ((status & (I2C_M_RD)) != false) { + ret = pch_i2c_readbytes(i2c_adap, pmsg, (i + 1 == num), + (i == 0)); + } else { + ret = pch_i2c_writebytes(i2c_adap, pmsg, (i + 1 == num), + (i == 0)); + } + } + + adap->pch_i2c_xfer_in_progress = false; /* transfer completed */ + + mutex_unlock(&pch_mutex); + + return (ret < 0) ? ret : num; +} + +/** + * pch_i2c_func() - return the functionality of the I2C driver + * @adap: Pointer to struct i2c_algo_pch_data. + */ +static u32 pch_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR; +} + +static const struct i2c_algorithm pch_algorithm = { + .master_xfer = pch_i2c_xfer, + .functionality = pch_i2c_func +}; + +/** + * pch_i2c_disbl_int() - Disable PCH I2C interrupts + * @adap: Pointer to struct i2c_algo_pch_data. + */ +static void pch_i2c_disbl_int(struct i2c_algo_pch_data *adap) +{ + void __iomem *p = adap->pch_base_address; + + pch_clrbit(adap->pch_base_address, PCH_I2CCTL, NORMAL_INTR_ENBL); + + iowrite32(EEPROM_RST_INTR_DISBL, p + PCH_I2CESRMSK); + + iowrite32(BUFFER_MODE_INTR_DISBL, p + PCH_I2CBUFMSK); +} + +static int pch_i2c_probe(struct pci_dev *pdev, + const struct pci_device_id *id) +{ + void __iomem *base_addr; + int ret; + int i, j; + struct adapter_info *adap_info; + struct i2c_adapter *pch_adap; + + pch_pci_dbg(pdev, "Entered.\n"); + + adap_info = kzalloc((sizeof(struct adapter_info)), GFP_KERNEL); + if (adap_info == NULL) + return -ENOMEM; + + ret = pci_enable_device(pdev); + if (ret) { + pch_pci_err(pdev, "pci_enable_device FAILED\n"); + goto err_pci_enable; + } + + ret = pci_request_regions(pdev, KBUILD_MODNAME); + if (ret) { + pch_pci_err(pdev, "pci_request_regions FAILED\n"); + goto err_pci_req; + } + + base_addr = pci_iomap(pdev, 1, 0); + + if (base_addr == NULL) { + pch_pci_err(pdev, "pci_iomap FAILED\n"); + ret = -ENOMEM; + goto err_pci_iomap; + } + + /* Set the number of I2C channel instance */ + adap_info->ch_num = id->driver_data; + + for (i = 0; i < adap_info->ch_num; i++) { + pch_adap = &adap_info->pch_data[i].pch_adapter; + adap_info->pch_i2c_suspended = false; + + adap_info->pch_data[i].p_adapter_info = adap_info; + + pch_adap->owner = THIS_MODULE; + pch_adap->class = I2C_CLASS_HWMON; + strscpy(pch_adap->name, KBUILD_MODNAME, sizeof(pch_adap->name)); + pch_adap->algo = &pch_algorithm; + pch_adap->algo_data = &adap_info->pch_data[i]; + + /* base_addr + offset; */ + adap_info->pch_data[i].pch_base_address = base_addr + 0x100 * i; + + pch_adap->dev.of_node = pdev->dev.of_node; + pch_adap->dev.parent = &pdev->dev; + } + + ret = request_irq(pdev->irq, pch_i2c_handler, IRQF_SHARED, + KBUILD_MODNAME, adap_info); + if (ret) { + pch_pci_err(pdev, "request_irq FAILED\n"); + goto err_request_irq; + } + + for (i = 0; i < adap_info->ch_num; i++) { + pch_adap = &adap_info->pch_data[i].pch_adapter; + + pch_i2c_init(&adap_info->pch_data[i]); + + pch_adap->nr = i; + ret = i2c_add_numbered_adapter(pch_adap); + if (ret) { + pch_pci_err(pdev, "i2c_add_adapter[ch:%d] FAILED\n", i); + goto err_add_adapter; + } + } + + pci_set_drvdata(pdev, adap_info); + pch_pci_dbg(pdev, "returns %d.\n", ret); + return 0; + +err_add_adapter: + for (j = 0; j < i; j++) + i2c_del_adapter(&adap_info->pch_data[j].pch_adapter); + free_irq(pdev->irq, adap_info); +err_request_irq: + pci_iounmap(pdev, base_addr); +err_pci_iomap: + pci_release_regions(pdev); +err_pci_req: + pci_disable_device(pdev); +err_pci_enable: + kfree(adap_info); + return ret; +} + +static void pch_i2c_remove(struct pci_dev *pdev) +{ + int i; + struct adapter_info *adap_info = pci_get_drvdata(pdev); + + free_irq(pdev->irq, adap_info); + + for (i = 0; i < adap_info->ch_num; i++) { + pch_i2c_disbl_int(&adap_info->pch_data[i]); + i2c_del_adapter(&adap_info->pch_data[i].pch_adapter); + } + + if (adap_info->pch_data[0].pch_base_address) + pci_iounmap(pdev, adap_info->pch_data[0].pch_base_address); + + for (i = 0; i < adap_info->ch_num; i++) + adap_info->pch_data[i].pch_base_address = NULL; + + pci_release_regions(pdev); + + pci_disable_device(pdev); + kfree(adap_info); +} + +static int __maybe_unused pch_i2c_suspend(struct device *dev) +{ + int i; + struct pci_dev *pdev = to_pci_dev(dev); + struct adapter_info *adap_info = pci_get_drvdata(pdev); + void __iomem *p = adap_info->pch_data[0].pch_base_address; + + adap_info->pch_i2c_suspended = true; + + for (i = 0; i < adap_info->ch_num; i++) { + while ((adap_info->pch_data[i].pch_i2c_xfer_in_progress)) { + /* Wait until all channel transfers are completed */ + msleep(20); + } + } + + /* Disable the i2c interrupts */ + for (i = 0; i < adap_info->ch_num; i++) + pch_i2c_disbl_int(&adap_info->pch_data[i]); + + pch_pci_dbg(pdev, "I2CSR = %x I2CBUFSTA = %x I2CESRSTA = %x " + "invoked function pch_i2c_disbl_int successfully\n", + ioread32(p + PCH_I2CSR), ioread32(p + PCH_I2CBUFSTA), + ioread32(p + PCH_I2CESRSTA)); + + return 0; +} + +static int __maybe_unused pch_i2c_resume(struct device *dev) +{ + int i; + struct adapter_info *adap_info = dev_get_drvdata(dev); + + for (i = 0; i < adap_info->ch_num; i++) + pch_i2c_init(&adap_info->pch_data[i]); + + adap_info->pch_i2c_suspended = false; + + return 0; +} + +static SIMPLE_DEV_PM_OPS(pch_i2c_pm_ops, pch_i2c_suspend, pch_i2c_resume); + +static struct pci_driver pch_pcidriver = { + .name = KBUILD_MODNAME, + .id_table = pch_pcidev_id, + .probe = pch_i2c_probe, + .remove = pch_i2c_remove, + .driver.pm = &pch_i2c_pm_ops, +}; + +module_pci_driver(pch_pcidriver); + +MODULE_DESCRIPTION("Intel EG20T PCH/LAPIS Semico ML7213/ML7223/ML7831 IOH I2C"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Tomoya MORINAGA. <tomoya.rohm@gmail.com>"); +module_param(pch_i2c_speed, int, (S_IRUSR | S_IWUSR)); +module_param(pch_clk, int, (S_IRUSR | S_IWUSR)); diff --git a/drivers/i2c/busses/i2c-elektor.c b/drivers/i2c/busses/i2c-elektor.c new file mode 100644 index 000000000..b0f50dce9 --- /dev/null +++ b/drivers/i2c/busses/i2c-elektor.c @@ -0,0 +1,321 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* ------------------------------------------------------------------------- */ +/* i2c-elektor.c i2c-hw access for PCF8584 style isa bus adaptes */ +/* ------------------------------------------------------------------------- */ +/* Copyright (C) 1995-97 Simon G. Vogl + 1998-99 Hans Berglund + + */ +/* ------------------------------------------------------------------------- */ + +/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and even + Frodo Looijaard <frodol@dds.nl> */ + +/* Partially rewriten by Oleg I. Vdovikin for mmapped support of + for Alpha Processor Inc. UP-2000(+) boards */ + +#include <linux/kernel.h> +#include <linux/ioport.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/pci.h> +#include <linux/wait.h> + +#include <linux/isa.h> +#include <linux/i2c.h> +#include <linux/i2c-algo-pcf.h> +#include <linux/io.h> + +#include <asm/irq.h> + +#include "../algos/i2c-algo-pcf.h" + +#define DEFAULT_BASE 0x330 + +static int base; +static u8 __iomem *base_iomem; + +static int irq; +static int clock = 0x1c; +static int own = 0x55; +static int mmapped; + +/* vdovikin: removed static struct i2c_pcf_isa gpi; code - + this module in real supports only one device, due to missing arguments + in some functions, called from the algo-pcf module. Sometimes it's + need to be rewriten - but for now just remove this for simpler reading */ + +static wait_queue_head_t pcf_wait; +static int pcf_pending; +static DEFINE_SPINLOCK(lock); + +static struct i2c_adapter pcf_isa_ops; + +/* ----- local functions ---------------------------------------------- */ + +static void pcf_isa_setbyte(void *data, int ctl, int val) +{ + u8 __iomem *address = ctl ? (base_iomem + 1) : base_iomem; + + /* enable irq if any specified for serial operation */ + if (ctl && irq && (val & I2C_PCF_ESO)) { + val |= I2C_PCF_ENI; + } + + pr_debug("%s: Write %p 0x%02X\n", pcf_isa_ops.name, address, val); + iowrite8(val, address); +#ifdef __alpha__ + /* API UP2000 needs some hardware fudging to make the write stick */ + iowrite8(val, address); +#endif +} + +static int pcf_isa_getbyte(void *data, int ctl) +{ + u8 __iomem *address = ctl ? (base_iomem + 1) : base_iomem; + int val = ioread8(address); + + pr_debug("%s: Read %p 0x%02X\n", pcf_isa_ops.name, address, val); + return (val); +} + +static int pcf_isa_getown(void *data) +{ + return (own); +} + + +static int pcf_isa_getclock(void *data) +{ + return (clock); +} + +static void pcf_isa_waitforpin(void *data) +{ + DEFINE_WAIT(wait); + int timeout = 2; + unsigned long flags; + + if (irq > 0) { + spin_lock_irqsave(&lock, flags); + if (pcf_pending == 0) { + spin_unlock_irqrestore(&lock, flags); + prepare_to_wait(&pcf_wait, &wait, TASK_INTERRUPTIBLE); + if (schedule_timeout(timeout*HZ)) { + spin_lock_irqsave(&lock, flags); + if (pcf_pending == 1) { + pcf_pending = 0; + } + spin_unlock_irqrestore(&lock, flags); + } + finish_wait(&pcf_wait, &wait); + } else { + pcf_pending = 0; + spin_unlock_irqrestore(&lock, flags); + } + } else { + udelay(100); + } +} + + +static irqreturn_t pcf_isa_handler(int this_irq, void *dev_id) { + spin_lock(&lock); + pcf_pending = 1; + spin_unlock(&lock); + wake_up_interruptible(&pcf_wait); + return IRQ_HANDLED; +} + + +static int pcf_isa_init(void) +{ + if (!mmapped) { + if (!request_region(base, 2, pcf_isa_ops.name)) { + printk(KERN_ERR "%s: requested I/O region (%#x:2) is " + "in use\n", pcf_isa_ops.name, base); + return -ENODEV; + } + base_iomem = ioport_map(base, 2); + if (!base_iomem) { + printk(KERN_ERR "%s: remap of I/O region %#x failed\n", + pcf_isa_ops.name, base); + release_region(base, 2); + return -ENODEV; + } + } else { + if (!request_mem_region(base, 2, pcf_isa_ops.name)) { + printk(KERN_ERR "%s: requested memory region (%#x:2) " + "is in use\n", pcf_isa_ops.name, base); + return -ENODEV; + } + base_iomem = ioremap(base, 2); + if (base_iomem == NULL) { + printk(KERN_ERR "%s: remap of memory region %#x " + "failed\n", pcf_isa_ops.name, base); + release_mem_region(base, 2); + return -ENODEV; + } + } + pr_debug("%s: registers %#x remapped to %p\n", pcf_isa_ops.name, base, + base_iomem); + + if (irq > 0) { + if (request_irq(irq, pcf_isa_handler, 0, pcf_isa_ops.name, + NULL) < 0) { + printk(KERN_ERR "%s: Request irq%d failed\n", + pcf_isa_ops.name, irq); + irq = 0; + } else + enable_irq(irq); + } + return 0; +} + +/* ------------------------------------------------------------------------ + * Encapsulate the above functions in the correct operations structure. + * This is only done when more than one hardware adapter is supported. + */ +static struct i2c_algo_pcf_data pcf_isa_data = { + .setpcf = pcf_isa_setbyte, + .getpcf = pcf_isa_getbyte, + .getown = pcf_isa_getown, + .getclock = pcf_isa_getclock, + .waitforpin = pcf_isa_waitforpin, +}; + +static struct i2c_adapter pcf_isa_ops = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo_data = &pcf_isa_data, + .name = "i2c-elektor", +}; + +static int elektor_match(struct device *dev, unsigned int id) +{ +#ifdef __alpha__ + /* check to see we have memory mapped PCF8584 connected to the + Cypress cy82c693 PCI-ISA bridge as on UP2000 board */ + if (base == 0) { + struct pci_dev *cy693_dev; + + cy693_dev = pci_get_device(PCI_VENDOR_ID_CONTAQ, + PCI_DEVICE_ID_CONTAQ_82C693, NULL); + if (cy693_dev) { + unsigned char config; + /* yeap, we've found cypress, let's check config */ + if (!pci_read_config_byte(cy693_dev, 0x47, &config)) { + + dev_dbg(dev, "found cy82c693, config " + "register 0x47 = 0x%02x\n", config); + + /* UP2000 board has this register set to 0xe1, + but the most significant bit as seems can be + reset during the proper initialisation + sequence if guys from API decides to do that + (so, we can even enable Tsunami Pchip + window for the upper 1 Gb) */ + + /* so just check for ROMCS at 0xe0000, + ROMCS enabled for writes + and external XD Bus buffer in use. */ + if ((config & 0x7f) == 0x61) { + /* seems to be UP2000 like board */ + base = 0xe0000; + mmapped = 1; + /* UP2000 drives ISA with + 8.25 MHz (PCI/4) clock + (this can be read from cypress) */ + clock = I2C_PCF_CLK | I2C_PCF_TRNS90; + dev_info(dev, "found API UP2000 like " + "board, will probe PCF8584 " + "later\n"); + } + } + pci_dev_put(cy693_dev); + } + } +#endif + + /* sanity checks for mmapped I/O */ + if (mmapped && base < 0xc8000) { + dev_err(dev, "incorrect base address (%#x) specified " + "for mmapped I/O\n", base); + return 0; + } + + if (base == 0) { + base = DEFAULT_BASE; + } + return 1; +} + +static int elektor_probe(struct device *dev, unsigned int id) +{ + init_waitqueue_head(&pcf_wait); + if (pcf_isa_init()) + return -ENODEV; + pcf_isa_ops.dev.parent = dev; + if (i2c_pcf_add_bus(&pcf_isa_ops) < 0) + goto fail; + + dev_info(dev, "found device at %#x\n", base); + + return 0; + + fail: + if (irq > 0) { + disable_irq(irq); + free_irq(irq, NULL); + } + + if (!mmapped) { + ioport_unmap(base_iomem); + release_region(base, 2); + } else { + iounmap(base_iomem); + release_mem_region(base, 2); + } + return -ENODEV; +} + +static void elektor_remove(struct device *dev, unsigned int id) +{ + i2c_del_adapter(&pcf_isa_ops); + + if (irq > 0) { + disable_irq(irq); + free_irq(irq, NULL); + } + + if (!mmapped) { + ioport_unmap(base_iomem); + release_region(base, 2); + } else { + iounmap(base_iomem); + release_mem_region(base, 2); + } +} + +static struct isa_driver i2c_elektor_driver = { + .match = elektor_match, + .probe = elektor_probe, + .remove = elektor_remove, + .driver = { + .owner = THIS_MODULE, + .name = "i2c-elektor", + }, +}; + +MODULE_AUTHOR("Hans Berglund <hb@spacetec.no>"); +MODULE_DESCRIPTION("I2C-Bus adapter routines for PCF8584 ISA bus adapter"); +MODULE_LICENSE("GPL"); + +module_param_hw(base, int, ioport_or_iomem, 0); +module_param_hw(irq, int, irq, 0); +module_param(clock, int, 0); +module_param(own, int, 0); +module_param_hw(mmapped, int, other, 0); +module_isa_driver(i2c_elektor_driver, 1); diff --git a/drivers/i2c/busses/i2c-emev2.c b/drivers/i2c/busses/i2c-emev2.c new file mode 100644 index 000000000..557409410 --- /dev/null +++ b/drivers/i2c/busses/i2c-emev2.c @@ -0,0 +1,449 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * I2C driver for the Renesas EMEV2 SoC + * + * Copyright (C) 2015 Wolfram Sang <wsa@sang-engineering.com> + * Copyright 2013 Codethink Ltd. + * Copyright 2010-2015 Renesas Electronics Corporation + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/device.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/sched.h> + +/* I2C Registers */ +#define I2C_OFS_IICACT0 0x00 /* start */ +#define I2C_OFS_IIC0 0x04 /* shift */ +#define I2C_OFS_IICC0 0x08 /* control */ +#define I2C_OFS_SVA0 0x0c /* slave address */ +#define I2C_OFS_IICCL0 0x10 /* clock select */ +#define I2C_OFS_IICX0 0x14 /* extension */ +#define I2C_OFS_IICS0 0x18 /* status */ +#define I2C_OFS_IICSE0 0x1c /* status For emulation */ +#define I2C_OFS_IICF0 0x20 /* IIC flag */ + +/* I2C IICACT0 Masks */ +#define I2C_BIT_IICE0 0x0001 + +/* I2C IICC0 Masks */ +#define I2C_BIT_LREL0 0x0040 +#define I2C_BIT_WREL0 0x0020 +#define I2C_BIT_SPIE0 0x0010 +#define I2C_BIT_WTIM0 0x0008 +#define I2C_BIT_ACKE0 0x0004 +#define I2C_BIT_STT0 0x0002 +#define I2C_BIT_SPT0 0x0001 + +/* I2C IICCL0 Masks */ +#define I2C_BIT_SMC0 0x0008 +#define I2C_BIT_DFC0 0x0004 + +/* I2C IICSE0 Masks */ +#define I2C_BIT_MSTS0 0x0080 +#define I2C_BIT_ALD0 0x0040 +#define I2C_BIT_EXC0 0x0020 +#define I2C_BIT_COI0 0x0010 +#define I2C_BIT_TRC0 0x0008 +#define I2C_BIT_ACKD0 0x0004 +#define I2C_BIT_STD0 0x0002 +#define I2C_BIT_SPD0 0x0001 + +/* I2C IICF0 Masks */ +#define I2C_BIT_STCF 0x0080 +#define I2C_BIT_IICBSY 0x0040 +#define I2C_BIT_STCEN 0x0002 +#define I2C_BIT_IICRSV 0x0001 + +struct em_i2c_device { + void __iomem *base; + struct i2c_adapter adap; + struct completion msg_done; + struct clk *sclk; + struct i2c_client *slave; + int irq; +}; + +static inline void em_clear_set_bit(struct em_i2c_device *priv, u8 clear, u8 set, u8 reg) +{ + writeb((readb(priv->base + reg) & ~clear) | set, priv->base + reg); +} + +static int em_i2c_wait_for_event(struct em_i2c_device *priv) +{ + unsigned long time_left; + int status; + + reinit_completion(&priv->msg_done); + + time_left = wait_for_completion_timeout(&priv->msg_done, priv->adap.timeout); + + if (!time_left) + return -ETIMEDOUT; + + status = readb(priv->base + I2C_OFS_IICSE0); + return status & I2C_BIT_ALD0 ? -EAGAIN : status; +} + +static void em_i2c_stop(struct em_i2c_device *priv) +{ + /* Send Stop condition */ + em_clear_set_bit(priv, 0, I2C_BIT_SPT0 | I2C_BIT_SPIE0, I2C_OFS_IICC0); + + /* Wait for stop condition */ + em_i2c_wait_for_event(priv); +} + +static void em_i2c_reset(struct i2c_adapter *adap) +{ + struct em_i2c_device *priv = i2c_get_adapdata(adap); + int retr; + + /* If I2C active */ + if (readb(priv->base + I2C_OFS_IICACT0) & I2C_BIT_IICE0) { + /* Disable I2C operation */ + writeb(0, priv->base + I2C_OFS_IICACT0); + + retr = 1000; + while (readb(priv->base + I2C_OFS_IICACT0) == 1 && retr) + retr--; + WARN_ON(retr == 0); + } + + /* Transfer mode set */ + writeb(I2C_BIT_DFC0, priv->base + I2C_OFS_IICCL0); + + /* Can Issue start without detecting a stop, Reservation disabled. */ + writeb(I2C_BIT_STCEN | I2C_BIT_IICRSV, priv->base + I2C_OFS_IICF0); + + /* I2C enable, 9 bit interrupt mode */ + writeb(I2C_BIT_WTIM0, priv->base + I2C_OFS_IICC0); + + /* Enable I2C operation */ + writeb(I2C_BIT_IICE0, priv->base + I2C_OFS_IICACT0); + + retr = 1000; + while (readb(priv->base + I2C_OFS_IICACT0) == 0 && retr) + retr--; + WARN_ON(retr == 0); +} + +static int __em_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, + int stop) +{ + struct em_i2c_device *priv = i2c_get_adapdata(adap); + int count, status, read = !!(msg->flags & I2C_M_RD); + + /* Send start condition */ + em_clear_set_bit(priv, 0, I2C_BIT_ACKE0 | I2C_BIT_WTIM0, I2C_OFS_IICC0); + em_clear_set_bit(priv, 0, I2C_BIT_STT0, I2C_OFS_IICC0); + + /* Send slave address and R/W type */ + writeb(i2c_8bit_addr_from_msg(msg), priv->base + I2C_OFS_IIC0); + + /* Wait for transaction */ + status = em_i2c_wait_for_event(priv); + if (status < 0) + goto out_reset; + + /* Received NACK (result of setting slave address and R/W) */ + if (!(status & I2C_BIT_ACKD0)) { + em_i2c_stop(priv); + goto out; + } + + /* Extra setup for read transactions */ + if (read) { + /* 8 bit interrupt mode */ + em_clear_set_bit(priv, I2C_BIT_WTIM0, I2C_BIT_ACKE0, I2C_OFS_IICC0); + em_clear_set_bit(priv, I2C_BIT_WTIM0, I2C_BIT_WREL0, I2C_OFS_IICC0); + + /* Wait for transaction */ + status = em_i2c_wait_for_event(priv); + if (status < 0) + goto out_reset; + } + + /* Send / receive data */ + for (count = 0; count < msg->len; count++) { + if (read) { /* Read transaction */ + msg->buf[count] = readb(priv->base + I2C_OFS_IIC0); + em_clear_set_bit(priv, 0, I2C_BIT_WREL0, I2C_OFS_IICC0); + + } else { /* Write transaction */ + /* Received NACK */ + if (!(status & I2C_BIT_ACKD0)) { + em_i2c_stop(priv); + goto out; + } + + /* Write data */ + writeb(msg->buf[count], priv->base + I2C_OFS_IIC0); + } + + /* Wait for R/W transaction */ + status = em_i2c_wait_for_event(priv); + if (status < 0) + goto out_reset; + } + + if (stop) + em_i2c_stop(priv); + + return count; + +out_reset: + em_i2c_reset(adap); +out: + return status < 0 ? status : -ENXIO; +} + +static int em_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct em_i2c_device *priv = i2c_get_adapdata(adap); + int ret, i; + + if (readb(priv->base + I2C_OFS_IICF0) & I2C_BIT_IICBSY) + return -EAGAIN; + + for (i = 0; i < num; i++) { + ret = __em_i2c_xfer(adap, &msgs[i], (i == (num - 1))); + if (ret < 0) + return ret; + } + + /* I2C transfer completed */ + return num; +} + +static bool em_i2c_slave_irq(struct em_i2c_device *priv) +{ + u8 status, value; + enum i2c_slave_event event; + int ret; + + if (!priv->slave) + return false; + + status = readb(priv->base + I2C_OFS_IICSE0); + + /* Extension code, do not participate */ + if (status & I2C_BIT_EXC0) { + em_clear_set_bit(priv, 0, I2C_BIT_LREL0, I2C_OFS_IICC0); + return true; + } + + /* Stop detected, we don't know if it's for slave or master */ + if (status & I2C_BIT_SPD0) { + /* Notify slave device */ + i2c_slave_event(priv->slave, I2C_SLAVE_STOP, &value); + /* Pretend we did not handle the interrupt */ + return false; + } + + /* Only handle interrupts addressed to us */ + if (!(status & I2C_BIT_COI0)) + return false; + + /* Enable stop interrupts */ + em_clear_set_bit(priv, 0, I2C_BIT_SPIE0, I2C_OFS_IICC0); + + /* Transmission or Reception */ + if (status & I2C_BIT_TRC0) { + if (status & I2C_BIT_ACKD0) { + /* 9 bit interrupt mode */ + em_clear_set_bit(priv, 0, I2C_BIT_WTIM0, I2C_OFS_IICC0); + + /* Send data */ + event = status & I2C_BIT_STD0 ? + I2C_SLAVE_READ_REQUESTED : + I2C_SLAVE_READ_PROCESSED; + i2c_slave_event(priv->slave, event, &value); + writeb(value, priv->base + I2C_OFS_IIC0); + } else { + /* NACK, stop transmitting */ + em_clear_set_bit(priv, 0, I2C_BIT_LREL0, I2C_OFS_IICC0); + } + } else { + /* 8 bit interrupt mode */ + em_clear_set_bit(priv, I2C_BIT_WTIM0, I2C_BIT_ACKE0, + I2C_OFS_IICC0); + em_clear_set_bit(priv, I2C_BIT_WTIM0, I2C_BIT_WREL0, + I2C_OFS_IICC0); + + if (status & I2C_BIT_STD0) { + i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_REQUESTED, + &value); + } else { + /* Recv data */ + value = readb(priv->base + I2C_OFS_IIC0); + ret = i2c_slave_event(priv->slave, + I2C_SLAVE_WRITE_RECEIVED, &value); + if (ret < 0) + em_clear_set_bit(priv, I2C_BIT_ACKE0, 0, + I2C_OFS_IICC0); + } + } + + return true; +} + +static irqreturn_t em_i2c_irq_handler(int this_irq, void *dev_id) +{ + struct em_i2c_device *priv = dev_id; + + if (em_i2c_slave_irq(priv)) + return IRQ_HANDLED; + + complete(&priv->msg_done); + + return IRQ_HANDLED; +} + +static u32 em_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SLAVE; +} + +static int em_i2c_reg_slave(struct i2c_client *slave) +{ + struct em_i2c_device *priv = i2c_get_adapdata(slave->adapter); + + if (priv->slave) + return -EBUSY; + + if (slave->flags & I2C_CLIENT_TEN) + return -EAFNOSUPPORT; + + priv->slave = slave; + + /* Set slave address */ + writeb(slave->addr << 1, priv->base + I2C_OFS_SVA0); + + return 0; +} + +static int em_i2c_unreg_slave(struct i2c_client *slave) +{ + struct em_i2c_device *priv = i2c_get_adapdata(slave->adapter); + + WARN_ON(!priv->slave); + + writeb(0, priv->base + I2C_OFS_SVA0); + + /* + * Wait for interrupt to finish. New slave irqs cannot happen because we + * cleared the slave address and, thus, only extension codes will be + * detected which do not use the slave ptr. + */ + synchronize_irq(priv->irq); + priv->slave = NULL; + + return 0; +} + +static const struct i2c_algorithm em_i2c_algo = { + .master_xfer = em_i2c_xfer, + .functionality = em_i2c_func, + .reg_slave = em_i2c_reg_slave, + .unreg_slave = em_i2c_unreg_slave, +}; + +static int em_i2c_probe(struct platform_device *pdev) +{ + struct em_i2c_device *priv; + int ret; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->base)) + return PTR_ERR(priv->base); + + strscpy(priv->adap.name, "EMEV2 I2C", sizeof(priv->adap.name)); + + priv->sclk = devm_clk_get(&pdev->dev, "sclk"); + if (IS_ERR(priv->sclk)) + return PTR_ERR(priv->sclk); + + ret = clk_prepare_enable(priv->sclk); + if (ret) + return ret; + + priv->adap.timeout = msecs_to_jiffies(100); + priv->adap.retries = 5; + priv->adap.dev.parent = &pdev->dev; + priv->adap.algo = &em_i2c_algo; + priv->adap.owner = THIS_MODULE; + priv->adap.dev.of_node = pdev->dev.of_node; + + init_completion(&priv->msg_done); + + platform_set_drvdata(pdev, priv); + i2c_set_adapdata(&priv->adap, priv); + + em_i2c_reset(&priv->adap); + + ret = platform_get_irq(pdev, 0); + if (ret < 0) + goto err_clk; + priv->irq = ret; + ret = devm_request_irq(&pdev->dev, priv->irq, em_i2c_irq_handler, 0, + "em_i2c", priv); + if (ret) + goto err_clk; + + ret = i2c_add_adapter(&priv->adap); + + if (ret) + goto err_clk; + + dev_info(&pdev->dev, "Added i2c controller %d, irq %d\n", priv->adap.nr, + priv->irq); + + return 0; + +err_clk: + clk_disable_unprepare(priv->sclk); + return ret; +} + +static void em_i2c_remove(struct platform_device *dev) +{ + struct em_i2c_device *priv = platform_get_drvdata(dev); + + i2c_del_adapter(&priv->adap); + clk_disable_unprepare(priv->sclk); +} + +static const struct of_device_id em_i2c_ids[] = { + { .compatible = "renesas,iic-emev2", }, + { } +}; + +static struct platform_driver em_i2c_driver = { + .probe = em_i2c_probe, + .remove_new = em_i2c_remove, + .driver = { + .name = "em-i2c", + .of_match_table = em_i2c_ids, + } +}; +module_platform_driver(em_i2c_driver); + +MODULE_DESCRIPTION("EMEV2 I2C bus driver"); +MODULE_AUTHOR("Ian Molton"); +MODULE_AUTHOR("Wolfram Sang <wsa@sang-engineering.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_DEVICE_TABLE(of, em_i2c_ids); diff --git a/drivers/i2c/busses/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c new file mode 100644 index 000000000..2b0b9cdff --- /dev/null +++ b/drivers/i2c/busses/i2c-exynos5.c @@ -0,0 +1,955 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * i2c-exynos5.c - Samsung Exynos5 I2C Controller Driver + * + * Copyright (C) 2013 Samsung Electronics Co., Ltd. +*/ + +#include <linux/kernel.h> +#include <linux/module.h> + +#include <linux/i2c.h> +#include <linux/time.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/clk.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/spinlock.h> + +/* + * HSI2C controller from Samsung supports 2 modes of operation + * 1. Auto mode: Where in master automatically controls the whole transaction + * 2. Manual mode: Software controls the transaction by issuing commands + * START, READ, WRITE, STOP, RESTART in I2C_MANUAL_CMD register. + * + * Operation mode can be selected by setting AUTO_MODE bit in I2C_CONF register + * + * Special bits are available for both modes of operation to set commands + * and for checking transfer status + */ + +/* Register Map */ +#define HSI2C_CTL 0x00 +#define HSI2C_FIFO_CTL 0x04 +#define HSI2C_TRAILIG_CTL 0x08 +#define HSI2C_CLK_CTL 0x0C +#define HSI2C_CLK_SLOT 0x10 +#define HSI2C_INT_ENABLE 0x20 +#define HSI2C_INT_STATUS 0x24 +#define HSI2C_ERR_STATUS 0x2C +#define HSI2C_FIFO_STATUS 0x30 +#define HSI2C_TX_DATA 0x34 +#define HSI2C_RX_DATA 0x38 +#define HSI2C_CONF 0x40 +#define HSI2C_AUTO_CONF 0x44 +#define HSI2C_TIMEOUT 0x48 +#define HSI2C_MANUAL_CMD 0x4C +#define HSI2C_TRANS_STATUS 0x50 +#define HSI2C_TIMING_HS1 0x54 +#define HSI2C_TIMING_HS2 0x58 +#define HSI2C_TIMING_HS3 0x5C +#define HSI2C_TIMING_FS1 0x60 +#define HSI2C_TIMING_FS2 0x64 +#define HSI2C_TIMING_FS3 0x68 +#define HSI2C_TIMING_SLA 0x6C +#define HSI2C_ADDR 0x70 + +/* I2C_CTL Register bits */ +#define HSI2C_FUNC_MODE_I2C (1u << 0) +#define HSI2C_MASTER (1u << 3) +#define HSI2C_RXCHON (1u << 6) +#define HSI2C_TXCHON (1u << 7) +#define HSI2C_SW_RST (1u << 31) + +/* I2C_FIFO_CTL Register bits */ +#define HSI2C_RXFIFO_EN (1u << 0) +#define HSI2C_TXFIFO_EN (1u << 1) +#define HSI2C_RXFIFO_TRIGGER_LEVEL(x) ((x) << 4) +#define HSI2C_TXFIFO_TRIGGER_LEVEL(x) ((x) << 16) + +/* I2C_TRAILING_CTL Register bits */ +#define HSI2C_TRAILING_COUNT (0xf) + +/* I2C_INT_EN Register bits */ +#define HSI2C_INT_TX_ALMOSTEMPTY_EN (1u << 0) +#define HSI2C_INT_RX_ALMOSTFULL_EN (1u << 1) +#define HSI2C_INT_TRAILING_EN (1u << 6) + +/* I2C_INT_STAT Register bits */ +#define HSI2C_INT_TX_ALMOSTEMPTY (1u << 0) +#define HSI2C_INT_RX_ALMOSTFULL (1u << 1) +#define HSI2C_INT_TX_UNDERRUN (1u << 2) +#define HSI2C_INT_TX_OVERRUN (1u << 3) +#define HSI2C_INT_RX_UNDERRUN (1u << 4) +#define HSI2C_INT_RX_OVERRUN (1u << 5) +#define HSI2C_INT_TRAILING (1u << 6) +#define HSI2C_INT_I2C (1u << 9) + +#define HSI2C_INT_TRANS_DONE (1u << 7) +#define HSI2C_INT_TRANS_ABORT (1u << 8) +#define HSI2C_INT_NO_DEV_ACK (1u << 9) +#define HSI2C_INT_NO_DEV (1u << 10) +#define HSI2C_INT_TIMEOUT (1u << 11) +#define HSI2C_INT_I2C_TRANS (HSI2C_INT_TRANS_DONE | \ + HSI2C_INT_TRANS_ABORT | \ + HSI2C_INT_NO_DEV_ACK | \ + HSI2C_INT_NO_DEV | \ + HSI2C_INT_TIMEOUT) + +/* I2C_FIFO_STAT Register bits */ +#define HSI2C_RX_FIFO_EMPTY (1u << 24) +#define HSI2C_RX_FIFO_FULL (1u << 23) +#define HSI2C_RX_FIFO_LVL(x) ((x >> 16) & 0x7f) +#define HSI2C_TX_FIFO_EMPTY (1u << 8) +#define HSI2C_TX_FIFO_FULL (1u << 7) +#define HSI2C_TX_FIFO_LVL(x) ((x >> 0) & 0x7f) + +/* I2C_CONF Register bits */ +#define HSI2C_AUTO_MODE (1u << 31) +#define HSI2C_10BIT_ADDR_MODE (1u << 30) +#define HSI2C_HS_MODE (1u << 29) + +/* I2C_AUTO_CONF Register bits */ +#define HSI2C_READ_WRITE (1u << 16) +#define HSI2C_STOP_AFTER_TRANS (1u << 17) +#define HSI2C_MASTER_RUN (1u << 31) + +/* I2C_TIMEOUT Register bits */ +#define HSI2C_TIMEOUT_EN (1u << 31) +#define HSI2C_TIMEOUT_MASK 0xff + +/* I2C_MANUAL_CMD register bits */ +#define HSI2C_CMD_READ_DATA (1u << 4) +#define HSI2C_CMD_SEND_STOP (1u << 2) + +/* I2C_TRANS_STATUS register bits */ +#define HSI2C_MASTER_BUSY (1u << 17) +#define HSI2C_SLAVE_BUSY (1u << 16) + +/* I2C_TRANS_STATUS register bits for Exynos5 variant */ +#define HSI2C_TIMEOUT_AUTO (1u << 4) +#define HSI2C_NO_DEV (1u << 3) +#define HSI2C_NO_DEV_ACK (1u << 2) +#define HSI2C_TRANS_ABORT (1u << 1) +#define HSI2C_TRANS_DONE (1u << 0) + +/* I2C_TRANS_STATUS register bits for Exynos7 variant */ +#define HSI2C_MASTER_ST_MASK 0xf +#define HSI2C_MASTER_ST_IDLE 0x0 +#define HSI2C_MASTER_ST_START 0x1 +#define HSI2C_MASTER_ST_RESTART 0x2 +#define HSI2C_MASTER_ST_STOP 0x3 +#define HSI2C_MASTER_ST_MASTER_ID 0x4 +#define HSI2C_MASTER_ST_ADDR0 0x5 +#define HSI2C_MASTER_ST_ADDR1 0x6 +#define HSI2C_MASTER_ST_ADDR2 0x7 +#define HSI2C_MASTER_ST_ADDR_SR 0x8 +#define HSI2C_MASTER_ST_READ 0x9 +#define HSI2C_MASTER_ST_WRITE 0xa +#define HSI2C_MASTER_ST_NO_ACK 0xb +#define HSI2C_MASTER_ST_LOSE 0xc +#define HSI2C_MASTER_ST_WAIT 0xd +#define HSI2C_MASTER_ST_WAIT_CMD 0xe + +/* I2C_ADDR register bits */ +#define HSI2C_SLV_ADDR_SLV(x) ((x & 0x3ff) << 0) +#define HSI2C_SLV_ADDR_MAS(x) ((x & 0x3ff) << 10) +#define HSI2C_MASTER_ID(x) ((x & 0xff) << 24) +#define MASTER_ID(x) ((x & 0x7) + 0x08) + +#define EXYNOS5_I2C_TIMEOUT (msecs_to_jiffies(100)) + +enum i2c_type_exynos { + I2C_TYPE_EXYNOS5, + I2C_TYPE_EXYNOS7, + I2C_TYPE_EXYNOSAUTOV9, +}; + +struct exynos5_i2c { + struct i2c_adapter adap; + + struct i2c_msg *msg; + struct completion msg_complete; + unsigned int msg_ptr; + + unsigned int irq; + + void __iomem *regs; + struct clk *clk; /* operating clock */ + struct clk *pclk; /* bus clock */ + struct device *dev; + int state; + + spinlock_t lock; /* IRQ synchronization */ + + /* + * Since the TRANS_DONE bit is cleared on read, and we may read it + * either during an IRQ or after a transaction, keep track of its + * state here. + */ + int trans_done; + + /* Controller operating frequency */ + unsigned int op_clock; + + /* Version of HS-I2C Hardware */ + const struct exynos_hsi2c_variant *variant; +}; + +/** + * struct exynos_hsi2c_variant - platform specific HSI2C driver data + * @fifo_depth: the fifo depth supported by the HSI2C module + * @hw: the hardware variant of Exynos I2C controller + * + * Specifies platform specific configuration of HSI2C module. + * Note: A structure for driver specific platform data is used for future + * expansion of its usage. + */ +struct exynos_hsi2c_variant { + unsigned int fifo_depth; + enum i2c_type_exynos hw; +}; + +static const struct exynos_hsi2c_variant exynos5250_hsi2c_data = { + .fifo_depth = 64, + .hw = I2C_TYPE_EXYNOS5, +}; + +static const struct exynos_hsi2c_variant exynos5260_hsi2c_data = { + .fifo_depth = 16, + .hw = I2C_TYPE_EXYNOS5, +}; + +static const struct exynos_hsi2c_variant exynos7_hsi2c_data = { + .fifo_depth = 16, + .hw = I2C_TYPE_EXYNOS7, +}; + +static const struct exynos_hsi2c_variant exynosautov9_hsi2c_data = { + .fifo_depth = 64, + .hw = I2C_TYPE_EXYNOSAUTOV9, +}; + +static const struct of_device_id exynos5_i2c_match[] = { + { + .compatible = "samsung,exynos5-hsi2c", + .data = &exynos5250_hsi2c_data + }, { + .compatible = "samsung,exynos5250-hsi2c", + .data = &exynos5250_hsi2c_data + }, { + .compatible = "samsung,exynos5260-hsi2c", + .data = &exynos5260_hsi2c_data + }, { + .compatible = "samsung,exynos7-hsi2c", + .data = &exynos7_hsi2c_data + }, { + .compatible = "samsung,exynosautov9-hsi2c", + .data = &exynosautov9_hsi2c_data + }, {}, +}; +MODULE_DEVICE_TABLE(of, exynos5_i2c_match); + +static void exynos5_i2c_clr_pend_irq(struct exynos5_i2c *i2c) +{ + writel(readl(i2c->regs + HSI2C_INT_STATUS), + i2c->regs + HSI2C_INT_STATUS); +} + +/* + * exynos5_i2c_set_timing: updates the registers with appropriate + * timing values calculated + * + * Timing values for operation are calculated against either 100kHz + * or 1MHz controller operating frequency. + * + * Returns 0 on success, -EINVAL if the cycle length cannot + * be calculated. + */ +static int exynos5_i2c_set_timing(struct exynos5_i2c *i2c, bool hs_timings) +{ + u32 i2c_timing_s1; + u32 i2c_timing_s2; + u32 i2c_timing_s3; + u32 i2c_timing_sla; + unsigned int t_start_su, t_start_hd; + unsigned int t_stop_su; + unsigned int t_data_su, t_data_hd; + unsigned int t_scl_l, t_scl_h; + unsigned int t_sr_release; + unsigned int t_ftl_cycle; + unsigned int clkin = clk_get_rate(i2c->clk); + unsigned int op_clk = hs_timings ? i2c->op_clock : + (i2c->op_clock >= I2C_MAX_FAST_MODE_PLUS_FREQ) ? I2C_MAX_STANDARD_MODE_FREQ : + i2c->op_clock; + int div, clk_cycle, temp; + + /* + * In case of HSI2C controllers in ExynosAutoV9: + * + * FSCL = IPCLK / ((CLK_DIV + 1) * 16) + * T_SCL_LOW = IPCLK * (CLK_DIV + 1) * (N + M) + * [N : number of 0's in the TSCL_H_HS] + * [M : number of 0's in the TSCL_L_HS] + * T_SCL_HIGH = IPCLK * (CLK_DIV + 1) * (N + M) + * [N : number of 1's in the TSCL_H_HS] + * [M : number of 1's in the TSCL_L_HS] + * + * Result of (N + M) is always 8. + * In general case, we don't need to control timing_s1 and timing_s2. + */ + if (i2c->variant->hw == I2C_TYPE_EXYNOSAUTOV9) { + div = ((clkin / (16 * i2c->op_clock)) - 1); + i2c_timing_s3 = div << 16; + if (hs_timings) + writel(i2c_timing_s3, i2c->regs + HSI2C_TIMING_HS3); + else + writel(i2c_timing_s3, i2c->regs + HSI2C_TIMING_FS3); + + return 0; + } + + /* + * In case of HSI2C controller in Exynos5 series + * FPCLK / FI2C = + * (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2) + 8 + 2 * FLT_CYCLE + * + * In case of HSI2C controllers in Exynos7 series + * FPCLK / FI2C = + * (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2) + 8 + FLT_CYCLE + * + * clk_cycle := TSCLK_L + TSCLK_H + * temp := (CLK_DIV + 1) * (clk_cycle + 2) + * + * Constraints: 4 <= temp, 0 <= CLK_DIV < 256, 2 <= clk_cycle <= 510 + * + */ + t_ftl_cycle = (readl(i2c->regs + HSI2C_CONF) >> 16) & 0x7; + temp = clkin / op_clk - 8 - t_ftl_cycle; + if (i2c->variant->hw != I2C_TYPE_EXYNOS7) + temp -= t_ftl_cycle; + div = temp / 512; + clk_cycle = temp / (div + 1) - 2; + if (temp < 4 || div >= 256 || clk_cycle < 2) { + dev_err(i2c->dev, "%s clock set-up failed\n", + hs_timings ? "HS" : "FS"); + return -EINVAL; + } + + t_scl_l = clk_cycle / 2; + t_scl_h = clk_cycle / 2; + t_start_su = t_scl_l; + t_start_hd = t_scl_l; + t_stop_su = t_scl_l; + t_data_su = t_scl_l / 2; + t_data_hd = t_scl_l / 2; + t_sr_release = clk_cycle; + + i2c_timing_s1 = t_start_su << 24 | t_start_hd << 16 | t_stop_su << 8; + i2c_timing_s2 = t_data_su << 24 | t_scl_l << 8 | t_scl_h << 0; + i2c_timing_s3 = div << 16 | t_sr_release << 0; + i2c_timing_sla = t_data_hd << 0; + + dev_dbg(i2c->dev, "tSTART_SU: %X, tSTART_HD: %X, tSTOP_SU: %X\n", + t_start_su, t_start_hd, t_stop_su); + dev_dbg(i2c->dev, "tDATA_SU: %X, tSCL_L: %X, tSCL_H: %X\n", + t_data_su, t_scl_l, t_scl_h); + dev_dbg(i2c->dev, "nClkDiv: %X, tSR_RELEASE: %X\n", + div, t_sr_release); + dev_dbg(i2c->dev, "tDATA_HD: %X\n", t_data_hd); + + if (hs_timings) { + writel(i2c_timing_s1, i2c->regs + HSI2C_TIMING_HS1); + writel(i2c_timing_s2, i2c->regs + HSI2C_TIMING_HS2); + writel(i2c_timing_s3, i2c->regs + HSI2C_TIMING_HS3); + } else { + writel(i2c_timing_s1, i2c->regs + HSI2C_TIMING_FS1); + writel(i2c_timing_s2, i2c->regs + HSI2C_TIMING_FS2); + writel(i2c_timing_s3, i2c->regs + HSI2C_TIMING_FS3); + } + writel(i2c_timing_sla, i2c->regs + HSI2C_TIMING_SLA); + + return 0; +} + +static int exynos5_hsi2c_clock_setup(struct exynos5_i2c *i2c) +{ + /* always set Fast Speed timings */ + int ret = exynos5_i2c_set_timing(i2c, false); + + if (ret < 0 || i2c->op_clock < I2C_MAX_FAST_MODE_PLUS_FREQ) + return ret; + + return exynos5_i2c_set_timing(i2c, true); +} + +/* + * exynos5_i2c_init: configures the controller for I2C functionality + * Programs I2C controller for Master mode operation + */ +static void exynos5_i2c_init(struct exynos5_i2c *i2c) +{ + u32 i2c_conf = readl(i2c->regs + HSI2C_CONF); + u32 i2c_timeout = readl(i2c->regs + HSI2C_TIMEOUT); + + /* Clear to disable Timeout */ + i2c_timeout &= ~HSI2C_TIMEOUT_EN; + writel(i2c_timeout, i2c->regs + HSI2C_TIMEOUT); + + writel((HSI2C_FUNC_MODE_I2C | HSI2C_MASTER), + i2c->regs + HSI2C_CTL); + writel(HSI2C_TRAILING_COUNT, i2c->regs + HSI2C_TRAILIG_CTL); + + if (i2c->op_clock >= I2C_MAX_FAST_MODE_PLUS_FREQ) { + writel(HSI2C_MASTER_ID(MASTER_ID(i2c->adap.nr)), + i2c->regs + HSI2C_ADDR); + i2c_conf |= HSI2C_HS_MODE; + } + + writel(i2c_conf | HSI2C_AUTO_MODE, i2c->regs + HSI2C_CONF); +} + +static void exynos5_i2c_reset(struct exynos5_i2c *i2c) +{ + u32 i2c_ctl; + + /* Set and clear the bit for reset */ + i2c_ctl = readl(i2c->regs + HSI2C_CTL); + i2c_ctl |= HSI2C_SW_RST; + writel(i2c_ctl, i2c->regs + HSI2C_CTL); + + i2c_ctl = readl(i2c->regs + HSI2C_CTL); + i2c_ctl &= ~HSI2C_SW_RST; + writel(i2c_ctl, i2c->regs + HSI2C_CTL); + + /* We don't expect calculations to fail during the run */ + exynos5_hsi2c_clock_setup(i2c); + /* Initialize the configure registers */ + exynos5_i2c_init(i2c); +} + +/* + * exynos5_i2c_irq: top level IRQ servicing routine + * + * INT_STATUS registers gives the interrupt details. Further, + * FIFO_STATUS or TRANS_STATUS registers are to be check for detailed + * state of the bus. + */ +static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id) +{ + struct exynos5_i2c *i2c = dev_id; + u32 fifo_level, int_status, fifo_status, trans_status; + unsigned char byte; + int len = 0; + + i2c->state = -EINVAL; + + spin_lock(&i2c->lock); + + int_status = readl(i2c->regs + HSI2C_INT_STATUS); + writel(int_status, i2c->regs + HSI2C_INT_STATUS); + + /* handle interrupt related to the transfer status */ + switch (i2c->variant->hw) { + case I2C_TYPE_EXYNOSAUTOV9: + fallthrough; + case I2C_TYPE_EXYNOS7: + if (int_status & HSI2C_INT_TRANS_DONE) { + i2c->trans_done = 1; + i2c->state = 0; + } else if (int_status & HSI2C_INT_TRANS_ABORT) { + dev_dbg(i2c->dev, "Deal with arbitration lose\n"); + i2c->state = -EAGAIN; + goto stop; + } else if (int_status & HSI2C_INT_NO_DEV_ACK) { + dev_dbg(i2c->dev, "No ACK from device\n"); + i2c->state = -ENXIO; + goto stop; + } else if (int_status & HSI2C_INT_NO_DEV) { + dev_dbg(i2c->dev, "No device\n"); + i2c->state = -ENXIO; + goto stop; + } else if (int_status & HSI2C_INT_TIMEOUT) { + dev_dbg(i2c->dev, "Accessing device timed out\n"); + i2c->state = -ETIMEDOUT; + goto stop; + } + + break; + case I2C_TYPE_EXYNOS5: + if (!(int_status & HSI2C_INT_I2C)) + break; + + trans_status = readl(i2c->regs + HSI2C_TRANS_STATUS); + if (trans_status & HSI2C_NO_DEV_ACK) { + dev_dbg(i2c->dev, "No ACK from device\n"); + i2c->state = -ENXIO; + goto stop; + } else if (trans_status & HSI2C_NO_DEV) { + dev_dbg(i2c->dev, "No device\n"); + i2c->state = -ENXIO; + goto stop; + } else if (trans_status & HSI2C_TRANS_ABORT) { + dev_dbg(i2c->dev, "Deal with arbitration lose\n"); + i2c->state = -EAGAIN; + goto stop; + } else if (trans_status & HSI2C_TIMEOUT_AUTO) { + dev_dbg(i2c->dev, "Accessing device timed out\n"); + i2c->state = -ETIMEDOUT; + goto stop; + } else if (trans_status & HSI2C_TRANS_DONE) { + i2c->trans_done = 1; + i2c->state = 0; + } + + break; + } + + if ((i2c->msg->flags & I2C_M_RD) && (int_status & + (HSI2C_INT_TRAILING | HSI2C_INT_RX_ALMOSTFULL))) { + fifo_status = readl(i2c->regs + HSI2C_FIFO_STATUS); + fifo_level = HSI2C_RX_FIFO_LVL(fifo_status); + len = min(fifo_level, i2c->msg->len - i2c->msg_ptr); + + while (len > 0) { + byte = (unsigned char) + readl(i2c->regs + HSI2C_RX_DATA); + i2c->msg->buf[i2c->msg_ptr++] = byte; + len--; + } + i2c->state = 0; + } else if (int_status & HSI2C_INT_TX_ALMOSTEMPTY) { + fifo_status = readl(i2c->regs + HSI2C_FIFO_STATUS); + fifo_level = HSI2C_TX_FIFO_LVL(fifo_status); + + len = i2c->variant->fifo_depth - fifo_level; + if (len > (i2c->msg->len - i2c->msg_ptr)) { + u32 int_en = readl(i2c->regs + HSI2C_INT_ENABLE); + + int_en &= ~HSI2C_INT_TX_ALMOSTEMPTY_EN; + writel(int_en, i2c->regs + HSI2C_INT_ENABLE); + len = i2c->msg->len - i2c->msg_ptr; + } + + while (len > 0) { + byte = i2c->msg->buf[i2c->msg_ptr++]; + writel(byte, i2c->regs + HSI2C_TX_DATA); + len--; + } + i2c->state = 0; + } + + stop: + if ((i2c->trans_done && (i2c->msg->len == i2c->msg_ptr)) || + (i2c->state < 0)) { + writel(0, i2c->regs + HSI2C_INT_ENABLE); + exynos5_i2c_clr_pend_irq(i2c); + complete(&i2c->msg_complete); + } + + spin_unlock(&i2c->lock); + + return IRQ_HANDLED; +} + +/* + * exynos5_i2c_wait_bus_idle + * + * Wait for the bus to go idle, indicated by the MASTER_BUSY bit being + * cleared. + * + * Returns -EBUSY if the bus cannot be bought to idle + */ +static int exynos5_i2c_wait_bus_idle(struct exynos5_i2c *i2c) +{ + unsigned long stop_time; + u32 trans_status; + + /* wait for 100 milli seconds for the bus to be idle */ + stop_time = jiffies + msecs_to_jiffies(100) + 1; + do { + trans_status = readl(i2c->regs + HSI2C_TRANS_STATUS); + if (!(trans_status & HSI2C_MASTER_BUSY)) + return 0; + + usleep_range(50, 200); + } while (time_before(jiffies, stop_time)); + + return -EBUSY; +} + +static void exynos5_i2c_bus_recover(struct exynos5_i2c *i2c) +{ + u32 val; + + val = readl(i2c->regs + HSI2C_CTL) | HSI2C_RXCHON; + writel(val, i2c->regs + HSI2C_CTL); + val = readl(i2c->regs + HSI2C_CONF) & ~HSI2C_AUTO_MODE; + writel(val, i2c->regs + HSI2C_CONF); + + /* + * Specification says master should send nine clock pulses. It can be + * emulated by sending manual read command (nine pulses for read eight + * bits + one pulse for NACK). + */ + writel(HSI2C_CMD_READ_DATA, i2c->regs + HSI2C_MANUAL_CMD); + exynos5_i2c_wait_bus_idle(i2c); + writel(HSI2C_CMD_SEND_STOP, i2c->regs + HSI2C_MANUAL_CMD); + exynos5_i2c_wait_bus_idle(i2c); + + val = readl(i2c->regs + HSI2C_CTL) & ~HSI2C_RXCHON; + writel(val, i2c->regs + HSI2C_CTL); + val = readl(i2c->regs + HSI2C_CONF) | HSI2C_AUTO_MODE; + writel(val, i2c->regs + HSI2C_CONF); +} + +static void exynos5_i2c_bus_check(struct exynos5_i2c *i2c) +{ + unsigned long timeout; + + if (i2c->variant->hw == I2C_TYPE_EXYNOS5) + return; + + /* + * HSI2C_MASTER_ST_LOSE state (in Exynos7 and ExynosAutoV9 variants) + * before transaction indicates that bus is stuck (SDA is low). + * In such case bus recovery can be performed. + */ + timeout = jiffies + msecs_to_jiffies(100); + for (;;) { + u32 st = readl(i2c->regs + HSI2C_TRANS_STATUS); + + if ((st & HSI2C_MASTER_ST_MASK) != HSI2C_MASTER_ST_LOSE) + return; + + if (time_is_before_jiffies(timeout)) + return; + + exynos5_i2c_bus_recover(i2c); + } +} + +/* + * exynos5_i2c_message_start: Configures the bus and starts the xfer + * i2c: struct exynos5_i2c pointer for the current bus + * stop: Enables stop after transfer if set. Set for last transfer of + * in the list of messages. + * + * Configures the bus for read/write function + * Sets chip address to talk to, message length to be sent. + * Enables appropriate interrupts and sends start xfer command. + */ +static void exynos5_i2c_message_start(struct exynos5_i2c *i2c, int stop) +{ + u32 i2c_ctl; + u32 int_en = 0; + u32 i2c_auto_conf = 0; + u32 i2c_addr = 0; + u32 fifo_ctl; + unsigned long flags; + unsigned short trig_lvl; + + if (i2c->variant->hw == I2C_TYPE_EXYNOS5) + int_en |= HSI2C_INT_I2C; + else + int_en |= HSI2C_INT_I2C_TRANS; + + i2c_ctl = readl(i2c->regs + HSI2C_CTL); + i2c_ctl &= ~(HSI2C_TXCHON | HSI2C_RXCHON); + fifo_ctl = HSI2C_RXFIFO_EN | HSI2C_TXFIFO_EN; + + if (i2c->msg->flags & I2C_M_RD) { + i2c_ctl |= HSI2C_RXCHON; + + i2c_auto_conf |= HSI2C_READ_WRITE; + + trig_lvl = (i2c->msg->len > i2c->variant->fifo_depth) ? + (i2c->variant->fifo_depth * 3 / 4) : i2c->msg->len; + fifo_ctl |= HSI2C_RXFIFO_TRIGGER_LEVEL(trig_lvl); + + int_en |= (HSI2C_INT_RX_ALMOSTFULL_EN | + HSI2C_INT_TRAILING_EN); + } else { + i2c_ctl |= HSI2C_TXCHON; + + trig_lvl = (i2c->msg->len > i2c->variant->fifo_depth) ? + (i2c->variant->fifo_depth * 1 / 4) : i2c->msg->len; + fifo_ctl |= HSI2C_TXFIFO_TRIGGER_LEVEL(trig_lvl); + + int_en |= HSI2C_INT_TX_ALMOSTEMPTY_EN; + } + + i2c_addr = HSI2C_SLV_ADDR_MAS(i2c->msg->addr); + + if (i2c->op_clock >= I2C_MAX_FAST_MODE_PLUS_FREQ) + i2c_addr |= HSI2C_MASTER_ID(MASTER_ID(i2c->adap.nr)); + + writel(i2c_addr, i2c->regs + HSI2C_ADDR); + + writel(fifo_ctl, i2c->regs + HSI2C_FIFO_CTL); + writel(i2c_ctl, i2c->regs + HSI2C_CTL); + + exynos5_i2c_bus_check(i2c); + + /* + * Enable interrupts before starting the transfer so that we don't + * miss any INT_I2C interrupts. + */ + spin_lock_irqsave(&i2c->lock, flags); + writel(int_en, i2c->regs + HSI2C_INT_ENABLE); + + if (stop == 1) + i2c_auto_conf |= HSI2C_STOP_AFTER_TRANS; + i2c_auto_conf |= i2c->msg->len; + i2c_auto_conf |= HSI2C_MASTER_RUN; + writel(i2c_auto_conf, i2c->regs + HSI2C_AUTO_CONF); + spin_unlock_irqrestore(&i2c->lock, flags); +} + +static int exynos5_i2c_xfer_msg(struct exynos5_i2c *i2c, + struct i2c_msg *msgs, int stop) +{ + unsigned long timeout; + int ret; + + i2c->msg = msgs; + i2c->msg_ptr = 0; + i2c->trans_done = 0; + + reinit_completion(&i2c->msg_complete); + + exynos5_i2c_message_start(i2c, stop); + + timeout = wait_for_completion_timeout(&i2c->msg_complete, + EXYNOS5_I2C_TIMEOUT); + if (timeout == 0) + ret = -ETIMEDOUT; + else + ret = i2c->state; + + /* + * If this is the last message to be transfered (stop == 1) + * Then check if the bus can be brought back to idle. + */ + if (ret == 0 && stop) + ret = exynos5_i2c_wait_bus_idle(i2c); + + if (ret < 0) { + exynos5_i2c_reset(i2c); + if (ret == -ETIMEDOUT) + dev_warn(i2c->dev, "%s timeout\n", + (msgs->flags & I2C_M_RD) ? "rx" : "tx"); + } + + /* Return the state as in interrupt routine */ + return ret; +} + +static int exynos5_i2c_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct exynos5_i2c *i2c = adap->algo_data; + int i, ret; + + ret = clk_enable(i2c->pclk); + if (ret) + return ret; + + ret = clk_enable(i2c->clk); + if (ret) + goto err_pclk; + + for (i = 0; i < num; ++i) { + ret = exynos5_i2c_xfer_msg(i2c, msgs + i, i + 1 == num); + if (ret) + break; + } + + clk_disable(i2c->clk); +err_pclk: + clk_disable(i2c->pclk); + + return ret ?: num; +} + +static u32 exynos5_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); +} + +static const struct i2c_algorithm exynos5_i2c_algorithm = { + .master_xfer = exynos5_i2c_xfer, + .functionality = exynos5_i2c_func, +}; + +static int exynos5_i2c_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct exynos5_i2c *i2c; + int ret; + + i2c = devm_kzalloc(&pdev->dev, sizeof(struct exynos5_i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + if (of_property_read_u32(np, "clock-frequency", &i2c->op_clock)) + i2c->op_clock = I2C_MAX_STANDARD_MODE_FREQ; + + strscpy(i2c->adap.name, "exynos5-i2c", sizeof(i2c->adap.name)); + i2c->adap.owner = THIS_MODULE; + i2c->adap.algo = &exynos5_i2c_algorithm; + i2c->adap.retries = 3; + + i2c->dev = &pdev->dev; + i2c->clk = devm_clk_get(&pdev->dev, "hsi2c"); + if (IS_ERR(i2c->clk)) { + dev_err(&pdev->dev, "cannot get clock\n"); + return -ENOENT; + } + + i2c->pclk = devm_clk_get_optional(&pdev->dev, "hsi2c_pclk"); + if (IS_ERR(i2c->pclk)) { + return dev_err_probe(&pdev->dev, PTR_ERR(i2c->pclk), + "cannot get pclk"); + } + + ret = clk_prepare_enable(i2c->pclk); + if (ret) + return ret; + + ret = clk_prepare_enable(i2c->clk); + if (ret) + goto err_pclk; + + i2c->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c->regs)) { + ret = PTR_ERR(i2c->regs); + goto err_clk; + } + + i2c->adap.dev.of_node = np; + i2c->adap.algo_data = i2c; + i2c->adap.dev.parent = &pdev->dev; + + /* Clear pending interrupts from u-boot or misc causes */ + exynos5_i2c_clr_pend_irq(i2c); + + spin_lock_init(&i2c->lock); + init_completion(&i2c->msg_complete); + + i2c->irq = ret = platform_get_irq(pdev, 0); + if (ret < 0) + goto err_clk; + + ret = devm_request_irq(&pdev->dev, i2c->irq, exynos5_i2c_irq, + IRQF_NO_SUSPEND, dev_name(&pdev->dev), i2c); + if (ret != 0) { + dev_err(&pdev->dev, "cannot request HS-I2C IRQ %d\n", i2c->irq); + goto err_clk; + } + + i2c->variant = of_device_get_match_data(&pdev->dev); + + ret = exynos5_hsi2c_clock_setup(i2c); + if (ret) + goto err_clk; + + exynos5_i2c_reset(i2c); + + ret = i2c_add_adapter(&i2c->adap); + if (ret < 0) + goto err_clk; + + platform_set_drvdata(pdev, i2c); + + clk_disable(i2c->clk); + clk_disable(i2c->pclk); + + return 0; + + err_clk: + clk_disable_unprepare(i2c->clk); + + err_pclk: + clk_disable_unprepare(i2c->pclk); + return ret; +} + +static void exynos5_i2c_remove(struct platform_device *pdev) +{ + struct exynos5_i2c *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adap); + + clk_unprepare(i2c->clk); + clk_unprepare(i2c->pclk); +} + +static int exynos5_i2c_suspend_noirq(struct device *dev) +{ + struct exynos5_i2c *i2c = dev_get_drvdata(dev); + + i2c_mark_adapter_suspended(&i2c->adap); + clk_unprepare(i2c->clk); + clk_unprepare(i2c->pclk); + + return 0; +} + +static int exynos5_i2c_resume_noirq(struct device *dev) +{ + struct exynos5_i2c *i2c = dev_get_drvdata(dev); + int ret = 0; + + ret = clk_prepare_enable(i2c->pclk); + if (ret) + return ret; + + ret = clk_prepare_enable(i2c->clk); + if (ret) + goto err_pclk; + + ret = exynos5_hsi2c_clock_setup(i2c); + if (ret) + goto err_clk; + + exynos5_i2c_init(i2c); + clk_disable(i2c->clk); + clk_disable(i2c->pclk); + i2c_mark_adapter_resumed(&i2c->adap); + + return 0; + +err_clk: + clk_disable_unprepare(i2c->clk); +err_pclk: + clk_disable_unprepare(i2c->pclk); + return ret; +} + +static const struct dev_pm_ops exynos5_i2c_dev_pm_ops = { + NOIRQ_SYSTEM_SLEEP_PM_OPS(exynos5_i2c_suspend_noirq, + exynos5_i2c_resume_noirq) +}; + +static struct platform_driver exynos5_i2c_driver = { + .probe = exynos5_i2c_probe, + .remove_new = exynos5_i2c_remove, + .driver = { + .name = "exynos5-hsi2c", + .pm = pm_sleep_ptr(&exynos5_i2c_dev_pm_ops), + .of_match_table = exynos5_i2c_match, + }, +}; + +module_platform_driver(exynos5_i2c_driver); + +MODULE_DESCRIPTION("Exynos5 HS-I2C Bus driver"); +MODULE_AUTHOR("Naveen Krishna Chatradhi <ch.naveen@samsung.com>"); +MODULE_AUTHOR("Taekgyun Ko <taeggyun.ko@samsung.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-fsi.c b/drivers/i2c/busses/i2c-fsi.c new file mode 100644 index 000000000..10332693e --- /dev/null +++ b/drivers/i2c/busses/i2c-fsi.c @@ -0,0 +1,776 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * FSI-attached I2C master algorithm + * + * Copyright 2018 IBM Corporation + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/bitfield.h> +#include <linux/bitops.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/errno.h> +#include <linux/fsi.h> +#include <linux/i2c.h> +#include <linux/jiffies.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/slab.h> + +#define FSI_ENGID_I2C 0x7 + +#define I2C_DEFAULT_CLK_DIV 6 + +/* i2c registers */ +#define I2C_FSI_FIFO 0x00 +#define I2C_FSI_CMD 0x04 +#define I2C_FSI_MODE 0x08 +#define I2C_FSI_WATER_MARK 0x0C +#define I2C_FSI_INT_MASK 0x10 +#define I2C_FSI_INT_COND 0x14 +#define I2C_FSI_OR_INT_MASK 0x14 +#define I2C_FSI_INTS 0x18 +#define I2C_FSI_AND_INT_MASK 0x18 +#define I2C_FSI_STAT 0x1C +#define I2C_FSI_RESET_I2C 0x1C +#define I2C_FSI_ESTAT 0x20 +#define I2C_FSI_RESET_ERR 0x20 +#define I2C_FSI_RESID_LEN 0x24 +#define I2C_FSI_SET_SCL 0x24 +#define I2C_FSI_PORT_BUSY 0x28 +#define I2C_FSI_RESET_SCL 0x2C +#define I2C_FSI_SET_SDA 0x30 +#define I2C_FSI_RESET_SDA 0x34 + +/* cmd register */ +#define I2C_CMD_WITH_START BIT(31) +#define I2C_CMD_WITH_ADDR BIT(30) +#define I2C_CMD_RD_CONT BIT(29) +#define I2C_CMD_WITH_STOP BIT(28) +#define I2C_CMD_FORCELAUNCH BIT(27) +#define I2C_CMD_ADDR GENMASK(23, 17) +#define I2C_CMD_READ BIT(16) +#define I2C_CMD_LEN GENMASK(15, 0) + +/* mode register */ +#define I2C_MODE_CLKDIV GENMASK(31, 16) +#define I2C_MODE_PORT GENMASK(15, 10) +#define I2C_MODE_ENHANCED BIT(3) +#define I2C_MODE_DIAG BIT(2) +#define I2C_MODE_PACE_ALLOW BIT(1) +#define I2C_MODE_WRAP BIT(0) + +/* watermark register */ +#define I2C_WATERMARK_HI GENMASK(15, 12) +#define I2C_WATERMARK_LO GENMASK(7, 4) + +#define I2C_FIFO_HI_LVL 4 +#define I2C_FIFO_LO_LVL 4 + +/* interrupt register */ +#define I2C_INT_INV_CMD BIT(15) +#define I2C_INT_PARITY BIT(14) +#define I2C_INT_BE_OVERRUN BIT(13) +#define I2C_INT_BE_ACCESS BIT(12) +#define I2C_INT_LOST_ARB BIT(11) +#define I2C_INT_NACK BIT(10) +#define I2C_INT_DAT_REQ BIT(9) +#define I2C_INT_CMD_COMP BIT(8) +#define I2C_INT_STOP_ERR BIT(7) +#define I2C_INT_BUSY BIT(6) +#define I2C_INT_IDLE BIT(5) + +/* status register */ +#define I2C_STAT_INV_CMD BIT(31) +#define I2C_STAT_PARITY BIT(30) +#define I2C_STAT_BE_OVERRUN BIT(29) +#define I2C_STAT_BE_ACCESS BIT(28) +#define I2C_STAT_LOST_ARB BIT(27) +#define I2C_STAT_NACK BIT(26) +#define I2C_STAT_DAT_REQ BIT(25) +#define I2C_STAT_CMD_COMP BIT(24) +#define I2C_STAT_STOP_ERR BIT(23) +#define I2C_STAT_MAX_PORT GENMASK(22, 16) +#define I2C_STAT_ANY_INT BIT(15) +#define I2C_STAT_SCL_IN BIT(11) +#define I2C_STAT_SDA_IN BIT(10) +#define I2C_STAT_PORT_BUSY BIT(9) +#define I2C_STAT_SELF_BUSY BIT(8) +#define I2C_STAT_FIFO_COUNT GENMASK(7, 0) + +#define I2C_STAT_ERR (I2C_STAT_INV_CMD | \ + I2C_STAT_PARITY | \ + I2C_STAT_BE_OVERRUN | \ + I2C_STAT_BE_ACCESS | \ + I2C_STAT_LOST_ARB | \ + I2C_STAT_NACK | \ + I2C_STAT_STOP_ERR) +#define I2C_STAT_ANY_RESP (I2C_STAT_ERR | \ + I2C_STAT_DAT_REQ | \ + I2C_STAT_CMD_COMP) + +/* extended status register */ +#define I2C_ESTAT_FIFO_SZ GENMASK(31, 24) +#define I2C_ESTAT_SCL_IN_SY BIT(15) +#define I2C_ESTAT_SDA_IN_SY BIT(14) +#define I2C_ESTAT_S_SCL BIT(13) +#define I2C_ESTAT_S_SDA BIT(12) +#define I2C_ESTAT_M_SCL BIT(11) +#define I2C_ESTAT_M_SDA BIT(10) +#define I2C_ESTAT_HI_WATER BIT(9) +#define I2C_ESTAT_LO_WATER BIT(8) +#define I2C_ESTAT_PORT_BUSY BIT(7) +#define I2C_ESTAT_SELF_BUSY BIT(6) +#define I2C_ESTAT_VERSION GENMASK(4, 0) + +/* port busy register */ +#define I2C_PORT_BUSY_RESET BIT(31) + +/* wait for command complete or data request */ +#define I2C_CMD_SLEEP_MAX_US 500 +#define I2C_CMD_SLEEP_MIN_US 50 + +/* wait after reset; choose time from legacy driver */ +#define I2C_RESET_SLEEP_MAX_US 2000 +#define I2C_RESET_SLEEP_MIN_US 1000 + +/* choose timeout length from legacy driver; it's well tested */ +#define I2C_ABORT_TIMEOUT msecs_to_jiffies(100) + +struct fsi_i2c_master { + struct fsi_device *fsi; + u8 fifo_size; + struct list_head ports; + struct mutex lock; +}; + +struct fsi_i2c_port { + struct list_head list; + struct i2c_adapter adapter; + struct fsi_i2c_master *master; + u16 port; + u16 xfrd; +}; + +static int fsi_i2c_read_reg(struct fsi_device *fsi, unsigned int reg, + u32 *data) +{ + int rc; + __be32 data_be; + + rc = fsi_device_read(fsi, reg, &data_be, sizeof(data_be)); + if (rc) + return rc; + + *data = be32_to_cpu(data_be); + + return 0; +} + +static int fsi_i2c_write_reg(struct fsi_device *fsi, unsigned int reg, + u32 *data) +{ + __be32 data_be = cpu_to_be32p(data); + + return fsi_device_write(fsi, reg, &data_be, sizeof(data_be)); +} + +static int fsi_i2c_dev_init(struct fsi_i2c_master *i2c) +{ + int rc; + u32 mode = I2C_MODE_ENHANCED, extended_status, watermark; + u32 interrupt = 0; + + /* since we use polling, disable interrupts */ + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_INT_MASK, &interrupt); + if (rc) + return rc; + + mode |= FIELD_PREP(I2C_MODE_CLKDIV, I2C_DEFAULT_CLK_DIV); + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); + if (rc) + return rc; + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_ESTAT, &extended_status); + if (rc) + return rc; + + i2c->fifo_size = FIELD_GET(I2C_ESTAT_FIFO_SZ, extended_status); + watermark = FIELD_PREP(I2C_WATERMARK_HI, + i2c->fifo_size - I2C_FIFO_HI_LVL); + watermark |= FIELD_PREP(I2C_WATERMARK_LO, I2C_FIFO_LO_LVL); + + return fsi_i2c_write_reg(i2c->fsi, I2C_FSI_WATER_MARK, &watermark); +} + +static int fsi_i2c_set_port(struct fsi_i2c_port *port) +{ + int rc; + struct fsi_device *fsi = port->master->fsi; + u32 mode, dummy = 0; + + rc = fsi_i2c_read_reg(fsi, I2C_FSI_MODE, &mode); + if (rc) + return rc; + + if (FIELD_GET(I2C_MODE_PORT, mode) == port->port) + return 0; + + mode = (mode & ~I2C_MODE_PORT) | FIELD_PREP(I2C_MODE_PORT, port->port); + rc = fsi_i2c_write_reg(fsi, I2C_FSI_MODE, &mode); + if (rc) + return rc; + + /* reset engine when port is changed */ + return fsi_i2c_write_reg(fsi, I2C_FSI_RESET_ERR, &dummy); +} + +static int fsi_i2c_start(struct fsi_i2c_port *port, struct i2c_msg *msg, + bool stop) +{ + struct fsi_i2c_master *i2c = port->master; + u32 cmd = I2C_CMD_WITH_START | I2C_CMD_WITH_ADDR; + + port->xfrd = 0; + + if (msg->flags & I2C_M_RD) + cmd |= I2C_CMD_READ; + + if (stop || msg->flags & I2C_M_STOP) + cmd |= I2C_CMD_WITH_STOP; + + cmd |= FIELD_PREP(I2C_CMD_ADDR, msg->addr); + cmd |= FIELD_PREP(I2C_CMD_LEN, msg->len); + + return fsi_i2c_write_reg(i2c->fsi, I2C_FSI_CMD, &cmd); +} + +static int fsi_i2c_get_op_bytes(int op_bytes) +{ + /* fsi is limited to max 4 byte aligned ops */ + if (op_bytes > 4) + return 4; + else if (op_bytes == 3) + return 2; + return op_bytes; +} + +static int fsi_i2c_write_fifo(struct fsi_i2c_port *port, struct i2c_msg *msg, + u8 fifo_count) +{ + int write; + int rc; + struct fsi_i2c_master *i2c = port->master; + int bytes_to_write = i2c->fifo_size - fifo_count; + int bytes_remaining = msg->len - port->xfrd; + + bytes_to_write = min(bytes_to_write, bytes_remaining); + + while (bytes_to_write) { + write = fsi_i2c_get_op_bytes(bytes_to_write); + + rc = fsi_device_write(i2c->fsi, I2C_FSI_FIFO, + &msg->buf[port->xfrd], write); + if (rc) + return rc; + + port->xfrd += write; + bytes_to_write -= write; + } + + return 0; +} + +static int fsi_i2c_read_fifo(struct fsi_i2c_port *port, struct i2c_msg *msg, + u8 fifo_count) +{ + int read; + int rc; + struct fsi_i2c_master *i2c = port->master; + int bytes_to_read; + int xfr_remaining = msg->len - port->xfrd; + u32 dummy; + + bytes_to_read = min_t(int, fifo_count, xfr_remaining); + + while (bytes_to_read) { + read = fsi_i2c_get_op_bytes(bytes_to_read); + + if (xfr_remaining) { + rc = fsi_device_read(i2c->fsi, I2C_FSI_FIFO, + &msg->buf[port->xfrd], read); + if (rc) + return rc; + + port->xfrd += read; + xfr_remaining -= read; + } else { + /* no more buffer but data in fifo, need to clear it */ + rc = fsi_device_read(i2c->fsi, I2C_FSI_FIFO, &dummy, + read); + if (rc) + return rc; + } + + bytes_to_read -= read; + } + + return 0; +} + +static int fsi_i2c_get_scl(struct i2c_adapter *adap) +{ + u32 stat = 0; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *i2c = port->master; + + fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat); + + return !!(stat & I2C_STAT_SCL_IN); +} + +static void fsi_i2c_set_scl(struct i2c_adapter *adap, int val) +{ + u32 dummy = 0; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *i2c = port->master; + + if (val) + fsi_i2c_write_reg(i2c->fsi, I2C_FSI_SET_SCL, &dummy); + else + fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_SCL, &dummy); +} + +static int fsi_i2c_get_sda(struct i2c_adapter *adap) +{ + u32 stat = 0; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *i2c = port->master; + + fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat); + + return !!(stat & I2C_STAT_SDA_IN); +} + +static void fsi_i2c_set_sda(struct i2c_adapter *adap, int val) +{ + u32 dummy = 0; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *i2c = port->master; + + if (val) + fsi_i2c_write_reg(i2c->fsi, I2C_FSI_SET_SDA, &dummy); + else + fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_SDA, &dummy); +} + +static void fsi_i2c_prepare_recovery(struct i2c_adapter *adap) +{ + int rc; + u32 mode; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *i2c = port->master; + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_MODE, &mode); + if (rc) + return; + + mode |= I2C_MODE_DIAG; + fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); +} + +static void fsi_i2c_unprepare_recovery(struct i2c_adapter *adap) +{ + int rc; + u32 mode; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *i2c = port->master; + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_MODE, &mode); + if (rc) + return; + + mode &= ~I2C_MODE_DIAG; + fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); +} + +static int fsi_i2c_reset_bus(struct fsi_i2c_master *i2c, + struct fsi_i2c_port *port) +{ + int rc; + u32 stat, dummy = 0; + + /* force bus reset, ignore errors */ + i2c_recover_bus(&port->adapter); + + /* reset errors */ + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_ERR, &dummy); + if (rc) + return rc; + + /* wait for command complete */ + usleep_range(I2C_RESET_SLEEP_MIN_US, I2C_RESET_SLEEP_MAX_US); + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat); + if (rc) + return rc; + + if (stat & I2C_STAT_CMD_COMP) + return 0; + + /* failed to get command complete; reset engine again */ + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_I2C, &dummy); + if (rc) + return rc; + + /* re-init engine again */ + return fsi_i2c_dev_init(i2c); +} + +static int fsi_i2c_reset_engine(struct fsi_i2c_master *i2c, u16 port) +{ + int rc; + u32 mode, dummy = 0; + + /* reset engine */ + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_RESET_I2C, &dummy); + if (rc) + return rc; + + /* re-init engine */ + rc = fsi_i2c_dev_init(i2c); + if (rc) + return rc; + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_MODE, &mode); + if (rc) + return rc; + + /* set port; default after reset is 0 */ + if (port) { + mode &= ~I2C_MODE_PORT; + mode |= FIELD_PREP(I2C_MODE_PORT, port); + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); + if (rc) + return rc; + } + + /* reset busy register; hw workaround */ + dummy = I2C_PORT_BUSY_RESET; + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_PORT_BUSY, &dummy); + if (rc) + return rc; + + return 0; +} + +static int fsi_i2c_abort(struct fsi_i2c_port *port, u32 status) +{ + int rc; + unsigned long start; + u32 cmd = I2C_CMD_WITH_STOP; + u32 stat; + struct fsi_i2c_master *i2c = port->master; + struct fsi_device *fsi = i2c->fsi; + + rc = fsi_i2c_reset_engine(i2c, port->port); + if (rc) + return rc; + + rc = fsi_i2c_read_reg(fsi, I2C_FSI_STAT, &stat); + if (rc) + return rc; + + /* if sda is low, peform full bus reset */ + if (!(stat & I2C_STAT_SDA_IN)) { + rc = fsi_i2c_reset_bus(i2c, port); + if (rc) + return rc; + } + + /* skip final stop command for these errors */ + if (status & (I2C_STAT_PARITY | I2C_STAT_LOST_ARB | I2C_STAT_STOP_ERR)) + return 0; + + /* write stop command */ + rc = fsi_i2c_write_reg(fsi, I2C_FSI_CMD, &cmd); + if (rc) + return rc; + + /* wait until we see command complete in the master */ + start = jiffies; + + do { + rc = fsi_i2c_read_reg(fsi, I2C_FSI_STAT, &status); + if (rc) + return rc; + + if (status & I2C_STAT_CMD_COMP) + return 0; + + usleep_range(I2C_CMD_SLEEP_MIN_US, I2C_CMD_SLEEP_MAX_US); + } while (time_after(start + I2C_ABORT_TIMEOUT, jiffies)); + + return -ETIMEDOUT; +} + +static int fsi_i2c_handle_status(struct fsi_i2c_port *port, + struct i2c_msg *msg, u32 status) +{ + int rc; + u8 fifo_count; + + if (status & I2C_STAT_ERR) { + rc = fsi_i2c_abort(port, status); + if (rc) + return rc; + + if (status & I2C_STAT_INV_CMD) + return -EINVAL; + + if (status & (I2C_STAT_PARITY | I2C_STAT_BE_OVERRUN | + I2C_STAT_BE_ACCESS)) + return -EPROTO; + + if (status & I2C_STAT_NACK) + return -ENXIO; + + if (status & I2C_STAT_LOST_ARB) + return -EAGAIN; + + if (status & I2C_STAT_STOP_ERR) + return -EBADMSG; + + return -EIO; + } + + if (status & I2C_STAT_DAT_REQ) { + fifo_count = FIELD_GET(I2C_STAT_FIFO_COUNT, status); + + if (msg->flags & I2C_M_RD) + return fsi_i2c_read_fifo(port, msg, fifo_count); + + return fsi_i2c_write_fifo(port, msg, fifo_count); + } + + if (status & I2C_STAT_CMD_COMP) { + if (port->xfrd < msg->len) + return -ENODATA; + + return msg->len; + } + + return 0; +} + +static int fsi_i2c_wait(struct fsi_i2c_port *port, struct i2c_msg *msg, + unsigned long timeout) +{ + u32 status = 0; + int rc; + unsigned long start = jiffies; + + do { + rc = fsi_i2c_read_reg(port->master->fsi, I2C_FSI_STAT, + &status); + if (rc) + return rc; + + if (status & I2C_STAT_ANY_RESP) { + rc = fsi_i2c_handle_status(port, msg, status); + if (rc < 0) + return rc; + + /* cmd complete and all data xfrd */ + if (rc == msg->len) + return 0; + + /* need to xfr more data, but maybe don't need wait */ + continue; + } + + usleep_range(I2C_CMD_SLEEP_MIN_US, I2C_CMD_SLEEP_MAX_US); + } while (time_after(start + timeout, jiffies)); + + return -ETIMEDOUT; +} + +static int fsi_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + int i, rc; + unsigned long start_time; + struct fsi_i2c_port *port = adap->algo_data; + struct fsi_i2c_master *master = port->master; + struct i2c_msg *msg; + + mutex_lock(&master->lock); + + rc = fsi_i2c_set_port(port); + if (rc) + goto unlock; + + for (i = 0; i < num; i++) { + msg = msgs + i; + start_time = jiffies; + + rc = fsi_i2c_start(port, msg, i == num - 1); + if (rc) + goto unlock; + + rc = fsi_i2c_wait(port, msg, + adap->timeout - (jiffies - start_time)); + if (rc) + goto unlock; + } + +unlock: + mutex_unlock(&master->lock); + return rc ? : num; +} + +static u32 fsi_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_PROTOCOL_MANGLING | + I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_BLOCK_DATA; +} + +static struct i2c_bus_recovery_info fsi_i2c_bus_recovery_info = { + .recover_bus = i2c_generic_scl_recovery, + .get_scl = fsi_i2c_get_scl, + .set_scl = fsi_i2c_set_scl, + .get_sda = fsi_i2c_get_sda, + .set_sda = fsi_i2c_set_sda, + .prepare_recovery = fsi_i2c_prepare_recovery, + .unprepare_recovery = fsi_i2c_unprepare_recovery, +}; + +static const struct i2c_algorithm fsi_i2c_algorithm = { + .master_xfer = fsi_i2c_xfer, + .functionality = fsi_i2c_functionality, +}; + +static struct device_node *fsi_i2c_find_port_of_node(struct device_node *fsi, + int port) +{ + struct device_node *np; + u32 port_no; + int rc; + + for_each_child_of_node(fsi, np) { + rc = of_property_read_u32(np, "reg", &port_no); + if (!rc && port_no == port) + return np; + } + + return NULL; +} + +static int fsi_i2c_probe(struct device *dev) +{ + struct fsi_i2c_master *i2c; + struct fsi_i2c_port *port; + struct device_node *np; + u32 port_no, ports, stat; + int rc; + + i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + mutex_init(&i2c->lock); + i2c->fsi = to_fsi_dev(dev); + INIT_LIST_HEAD(&i2c->ports); + + rc = fsi_i2c_dev_init(i2c); + if (rc) + return rc; + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_STAT, &stat); + if (rc) + return rc; + + ports = FIELD_GET(I2C_STAT_MAX_PORT, stat) + 1; + dev_dbg(dev, "I2C master has %d ports\n", ports); + + for (port_no = 0; port_no < ports; port_no++) { + np = fsi_i2c_find_port_of_node(dev->of_node, port_no); + if (!of_device_is_available(np)) + continue; + + port = kzalloc(sizeof(*port), GFP_KERNEL); + if (!port) { + of_node_put(np); + break; + } + + port->master = i2c; + port->port = port_no; + + port->adapter.owner = THIS_MODULE; + port->adapter.dev.of_node = np; + port->adapter.dev.parent = dev; + port->adapter.algo = &fsi_i2c_algorithm; + port->adapter.bus_recovery_info = &fsi_i2c_bus_recovery_info; + port->adapter.algo_data = port; + + snprintf(port->adapter.name, sizeof(port->adapter.name), + "i2c_bus-%u", port_no); + + rc = i2c_add_adapter(&port->adapter); + if (rc < 0) { + dev_err(dev, "Failed to register adapter: %d\n", rc); + kfree(port); + continue; + } + + list_add(&port->list, &i2c->ports); + } + + dev_set_drvdata(dev, i2c); + + return 0; +} + +static int fsi_i2c_remove(struct device *dev) +{ + struct fsi_i2c_master *i2c = dev_get_drvdata(dev); + struct fsi_i2c_port *port, *tmp; + + list_for_each_entry_safe(port, tmp, &i2c->ports, list) { + list_del(&port->list); + i2c_del_adapter(&port->adapter); + kfree(port); + } + + return 0; +} + +static const struct fsi_device_id fsi_i2c_ids[] = { + { FSI_ENGID_I2C, FSI_VERSION_ANY }, + { } +}; + +static struct fsi_driver fsi_i2c_driver = { + .id_table = fsi_i2c_ids, + .drv = { + .name = "i2c-fsi", + .bus = &fsi_bus_type, + .probe = fsi_i2c_probe, + .remove = fsi_i2c_remove, + }, +}; + +module_fsi_driver(fsi_i2c_driver); + +MODULE_AUTHOR("Eddie James <eajames@us.ibm.com>"); +MODULE_DESCRIPTION("FSI attached I2C master"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c new file mode 100644 index 000000000..e5a5b9e8b --- /dev/null +++ b/drivers/i2c/busses/i2c-gpio.c @@ -0,0 +1,535 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Bitbanging I2C bus driver using the GPIO API + * + * Copyright (C) 2007 Atmel Corporation + */ +#include <linux/completion.h> +#include <linux/debugfs.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c-algo-bit.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/platform_data/i2c-gpio.h> +#include <linux/platform_device.h> +#include <linux/property.h> +#include <linux/slab.h> + +struct i2c_gpio_private_data { + struct gpio_desc *sda; + struct gpio_desc *scl; + struct i2c_adapter adap; + struct i2c_algo_bit_data bit_data; + struct i2c_gpio_platform_data pdata; +#ifdef CONFIG_I2C_GPIO_FAULT_INJECTOR + struct dentry *debug_dir; + /* these must be protected by bus lock */ + struct completion scl_irq_completion; + u64 scl_irq_data; +#endif +}; + +/* + * Toggle SDA by changing the output value of the pin. This is only + * valid for pins configured as open drain (i.e. setting the value + * high effectively turns off the output driver.) + */ +static void i2c_gpio_setsda_val(void *data, int state) +{ + struct i2c_gpio_private_data *priv = data; + + gpiod_set_value_cansleep(priv->sda, state); +} + +/* + * Toggle SCL by changing the output value of the pin. This is used + * for pins that are configured as open drain and for output-only + * pins. The latter case will break the i2c protocol, but it will + * often work in practice. + */ +static void i2c_gpio_setscl_val(void *data, int state) +{ + struct i2c_gpio_private_data *priv = data; + + gpiod_set_value_cansleep(priv->scl, state); +} + +static int i2c_gpio_getsda(void *data) +{ + struct i2c_gpio_private_data *priv = data; + + return gpiod_get_value_cansleep(priv->sda); +} + +static int i2c_gpio_getscl(void *data) +{ + struct i2c_gpio_private_data *priv = data; + + return gpiod_get_value_cansleep(priv->scl); +} + +#ifdef CONFIG_I2C_GPIO_FAULT_INJECTOR +static struct dentry *i2c_gpio_debug_dir; + +#define setsda(bd, val) ((bd)->setsda((bd)->data, val)) +#define setscl(bd, val) ((bd)->setscl((bd)->data, val)) +#define getsda(bd) ((bd)->getsda((bd)->data)) +#define getscl(bd) ((bd)->getscl((bd)->data)) + +#define WIRE_ATTRIBUTE(wire) \ +static int fops_##wire##_get(void *data, u64 *val) \ +{ \ + struct i2c_gpio_private_data *priv = data; \ + \ + i2c_lock_bus(&priv->adap, I2C_LOCK_ROOT_ADAPTER); \ + *val = get##wire(&priv->bit_data); \ + i2c_unlock_bus(&priv->adap, I2C_LOCK_ROOT_ADAPTER); \ + return 0; \ +} \ +static int fops_##wire##_set(void *data, u64 val) \ +{ \ + struct i2c_gpio_private_data *priv = data; \ + \ + i2c_lock_bus(&priv->adap, I2C_LOCK_ROOT_ADAPTER); \ + set##wire(&priv->bit_data, val); \ + i2c_unlock_bus(&priv->adap, I2C_LOCK_ROOT_ADAPTER); \ + return 0; \ +} \ +DEFINE_DEBUGFS_ATTRIBUTE(fops_##wire, fops_##wire##_get, fops_##wire##_set, "%llu\n") + +WIRE_ATTRIBUTE(scl); +WIRE_ATTRIBUTE(sda); + +static void i2c_gpio_incomplete_transfer(struct i2c_gpio_private_data *priv, + u32 pattern, u8 pattern_size) +{ + struct i2c_algo_bit_data *bit_data = &priv->bit_data; + int i; + + i2c_lock_bus(&priv->adap, I2C_LOCK_ROOT_ADAPTER); + + /* START condition */ + setsda(bit_data, 0); + udelay(bit_data->udelay); + + /* Send pattern, request ACK, don't send STOP */ + for (i = pattern_size - 1; i >= 0; i--) { + setscl(bit_data, 0); + udelay(bit_data->udelay / 2); + setsda(bit_data, (pattern >> i) & 1); + udelay((bit_data->udelay + 1) / 2); + setscl(bit_data, 1); + udelay(bit_data->udelay); + } + + i2c_unlock_bus(&priv->adap, I2C_LOCK_ROOT_ADAPTER); +} + +static int fops_incomplete_addr_phase_set(void *data, u64 addr) +{ + struct i2c_gpio_private_data *priv = data; + u32 pattern; + + if (addr > 0x7f) + return -EINVAL; + + /* ADDR (7 bit) + RD (1 bit) + Client ACK, keep SDA hi (1 bit) */ + pattern = (addr << 2) | 3; + + i2c_gpio_incomplete_transfer(priv, pattern, 9); + + return 0; +} +DEFINE_DEBUGFS_ATTRIBUTE(fops_incomplete_addr_phase, NULL, fops_incomplete_addr_phase_set, "%llu\n"); + +static int fops_incomplete_write_byte_set(void *data, u64 addr) +{ + struct i2c_gpio_private_data *priv = data; + u32 pattern; + + if (addr > 0x7f) + return -EINVAL; + + /* ADDR (7 bit) + WR (1 bit) + Client ACK (1 bit) */ + pattern = (addr << 2) | 1; + /* 0x00 (8 bit) + Client ACK, keep SDA hi (1 bit) */ + pattern = (pattern << 9) | 1; + + i2c_gpio_incomplete_transfer(priv, pattern, 18); + + return 0; +} +DEFINE_DEBUGFS_ATTRIBUTE(fops_incomplete_write_byte, NULL, fops_incomplete_write_byte_set, "%llu\n"); + +static int i2c_gpio_fi_act_on_scl_irq(struct i2c_gpio_private_data *priv, + irqreturn_t handler(int, void*)) +{ + int ret, irq = gpiod_to_irq(priv->scl); + + if (irq < 0) + return irq; + + i2c_lock_bus(&priv->adap, I2C_LOCK_ROOT_ADAPTER); + + ret = gpiod_direction_input(priv->scl); + if (ret) + goto unlock; + + reinit_completion(&priv->scl_irq_completion); + + ret = request_irq(irq, handler, IRQF_TRIGGER_FALLING, + "i2c_gpio_fault_injector_scl_irq", priv); + if (ret) + goto output; + + wait_for_completion_interruptible(&priv->scl_irq_completion); + + free_irq(irq, priv); + output: + ret = gpiod_direction_output(priv->scl, 1) ?: ret; + unlock: + i2c_unlock_bus(&priv->adap, I2C_LOCK_ROOT_ADAPTER); + + return ret; +} + +static irqreturn_t lose_arbitration_irq(int irq, void *dev_id) +{ + struct i2c_gpio_private_data *priv = dev_id; + + setsda(&priv->bit_data, 0); + udelay(priv->scl_irq_data); + setsda(&priv->bit_data, 1); + + complete(&priv->scl_irq_completion); + + return IRQ_HANDLED; +} + +static int fops_lose_arbitration_set(void *data, u64 duration) +{ + struct i2c_gpio_private_data *priv = data; + + if (duration > 100 * 1000) + return -EINVAL; + + priv->scl_irq_data = duration; + /* + * Interrupt on falling SCL. This ensures that the master under test has + * really started the transfer. Interrupt on falling SDA did only + * exercise 'bus busy' detection on some HW but not 'arbitration lost'. + * Note that the interrupt latency may cause the first bits to be + * transmitted correctly. + */ + return i2c_gpio_fi_act_on_scl_irq(priv, lose_arbitration_irq); +} +DEFINE_DEBUGFS_ATTRIBUTE(fops_lose_arbitration, NULL, fops_lose_arbitration_set, "%llu\n"); + +static irqreturn_t inject_panic_irq(int irq, void *dev_id) +{ + struct i2c_gpio_private_data *priv = dev_id; + + udelay(priv->scl_irq_data); + panic("I2C fault injector induced panic"); + + return IRQ_HANDLED; +} + +static int fops_inject_panic_set(void *data, u64 duration) +{ + struct i2c_gpio_private_data *priv = data; + + if (duration > 100 * 1000) + return -EINVAL; + + priv->scl_irq_data = duration; + /* + * Interrupt on falling SCL. This ensures that the master under test has + * really started the transfer. + */ + return i2c_gpio_fi_act_on_scl_irq(priv, inject_panic_irq); +} +DEFINE_DEBUGFS_ATTRIBUTE(fops_inject_panic, NULL, fops_inject_panic_set, "%llu\n"); + +static void i2c_gpio_fault_injector_init(struct platform_device *pdev) +{ + struct i2c_gpio_private_data *priv = platform_get_drvdata(pdev); + + /* + * If there will be a debugfs-dir per i2c adapter somewhen, put the + * 'fault-injector' dir there. Until then, we have a global dir with + * all adapters as subdirs. + */ + if (!i2c_gpio_debug_dir) { + i2c_gpio_debug_dir = debugfs_create_dir("i2c-fault-injector", NULL); + if (!i2c_gpio_debug_dir) + return; + } + + priv->debug_dir = debugfs_create_dir(pdev->name, i2c_gpio_debug_dir); + if (!priv->debug_dir) + return; + + init_completion(&priv->scl_irq_completion); + + debugfs_create_file_unsafe("incomplete_address_phase", 0200, priv->debug_dir, + priv, &fops_incomplete_addr_phase); + debugfs_create_file_unsafe("incomplete_write_byte", 0200, priv->debug_dir, + priv, &fops_incomplete_write_byte); + if (priv->bit_data.getscl) { + debugfs_create_file_unsafe("inject_panic", 0200, priv->debug_dir, + priv, &fops_inject_panic); + debugfs_create_file_unsafe("lose_arbitration", 0200, priv->debug_dir, + priv, &fops_lose_arbitration); + } + debugfs_create_file_unsafe("scl", 0600, priv->debug_dir, priv, &fops_scl); + debugfs_create_file_unsafe("sda", 0600, priv->debug_dir, priv, &fops_sda); +} + +static void i2c_gpio_fault_injector_exit(struct platform_device *pdev) +{ + struct i2c_gpio_private_data *priv = platform_get_drvdata(pdev); + + debugfs_remove_recursive(priv->debug_dir); +} +#else +static inline void i2c_gpio_fault_injector_init(struct platform_device *pdev) {} +static inline void i2c_gpio_fault_injector_exit(struct platform_device *pdev) {} +#endif /* CONFIG_I2C_GPIO_FAULT_INJECTOR*/ + +/* Get i2c-gpio properties from DT or ACPI table */ +static void i2c_gpio_get_properties(struct device *dev, + struct i2c_gpio_platform_data *pdata) +{ + u32 reg; + + device_property_read_u32(dev, "i2c-gpio,delay-us", &pdata->udelay); + + if (!device_property_read_u32(dev, "i2c-gpio,timeout-ms", ®)) + pdata->timeout = msecs_to_jiffies(reg); + + pdata->sda_is_open_drain = + device_property_read_bool(dev, "i2c-gpio,sda-open-drain"); + pdata->scl_is_open_drain = + device_property_read_bool(dev, "i2c-gpio,scl-open-drain"); + pdata->scl_is_output_only = + device_property_read_bool(dev, "i2c-gpio,scl-output-only"); + pdata->sda_is_output_only = + device_property_read_bool(dev, "i2c-gpio,sda-output-only"); + pdata->sda_has_no_pullup = + device_property_read_bool(dev, "i2c-gpio,sda-has-no-pullup"); + pdata->scl_has_no_pullup = + device_property_read_bool(dev, "i2c-gpio,scl-has-no-pullup"); +} + +static struct gpio_desc *i2c_gpio_get_desc(struct device *dev, + const char *con_id, + unsigned int index, + enum gpiod_flags gflags) +{ + struct gpio_desc *retdesc; + int ret; + + retdesc = devm_gpiod_get(dev, con_id, gflags); + if (!IS_ERR(retdesc)) { + dev_dbg(dev, "got GPIO from name %s\n", con_id); + return retdesc; + } + + retdesc = devm_gpiod_get_index(dev, NULL, index, gflags); + if (!IS_ERR(retdesc)) { + dev_dbg(dev, "got GPIO from index %u\n", index); + return retdesc; + } + + ret = PTR_ERR(retdesc); + + /* FIXME: hack in the old code, is this really necessary? */ + if (ret == -EINVAL) + retdesc = ERR_PTR(-EPROBE_DEFER); + + /* This happens if the GPIO driver is not yet probed, let's defer */ + if (ret == -ENOENT) + retdesc = ERR_PTR(-EPROBE_DEFER); + + if (PTR_ERR(retdesc) != -EPROBE_DEFER) + dev_err(dev, "error trying to get descriptor: %d\n", ret); + + return retdesc; +} + +static int i2c_gpio_probe(struct platform_device *pdev) +{ + struct i2c_gpio_private_data *priv; + struct i2c_gpio_platform_data *pdata; + struct i2c_algo_bit_data *bit_data; + struct i2c_adapter *adap; + struct device *dev = &pdev->dev; + struct fwnode_handle *fwnode = dev_fwnode(dev); + enum gpiod_flags gflags; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + adap = &priv->adap; + bit_data = &priv->bit_data; + pdata = &priv->pdata; + + if (fwnode) { + i2c_gpio_get_properties(dev, pdata); + } else { + /* + * If all platform data settings are zero it is OK + * to not provide any platform data from the board. + */ + if (dev_get_platdata(dev)) + memcpy(pdata, dev_get_platdata(dev), sizeof(*pdata)); + } + + /* + * First get the GPIO pins; if it fails, we'll defer the probe. + * If the SCL/SDA lines are marked "open drain" by platform data or + * device tree then this means that something outside of our control is + * marking these lines to be handled as open drain, and we should just + * handle them as we handle any other output. Else we enforce open + * drain as this is required for an I2C bus. + */ + if (pdata->sda_is_open_drain || pdata->sda_has_no_pullup) + gflags = GPIOD_OUT_HIGH; + else + gflags = GPIOD_OUT_HIGH_OPEN_DRAIN; + priv->sda = i2c_gpio_get_desc(dev, "sda", 0, gflags); + if (IS_ERR(priv->sda)) + return PTR_ERR(priv->sda); + + if (pdata->scl_is_open_drain || pdata->scl_has_no_pullup) + gflags = GPIOD_OUT_HIGH; + else + gflags = GPIOD_OUT_HIGH_OPEN_DRAIN; + priv->scl = i2c_gpio_get_desc(dev, "scl", 1, gflags); + if (IS_ERR(priv->scl)) + return PTR_ERR(priv->scl); + + if (gpiod_cansleep(priv->sda) || gpiod_cansleep(priv->scl)) + dev_warn(dev, "Slow GPIO pins might wreak havoc into I2C/SMBus bus timing"); + else + bit_data->can_do_atomic = true; + + bit_data->setsda = i2c_gpio_setsda_val; + bit_data->setscl = i2c_gpio_setscl_val; + + if (!pdata->scl_is_output_only) + bit_data->getscl = i2c_gpio_getscl; + if (!pdata->sda_is_output_only) + bit_data->getsda = i2c_gpio_getsda; + + if (pdata->udelay) + bit_data->udelay = pdata->udelay; + else if (pdata->scl_is_output_only) + bit_data->udelay = 50; /* 10 kHz */ + else + bit_data->udelay = 5; /* 100 kHz */ + + if (pdata->timeout) + bit_data->timeout = pdata->timeout; + else + bit_data->timeout = HZ / 10; /* 100 ms */ + + bit_data->data = priv; + + adap->owner = THIS_MODULE; + if (fwnode) + strscpy(adap->name, dev_name(dev), sizeof(adap->name)); + else + snprintf(adap->name, sizeof(adap->name), "i2c-gpio%d", pdev->id); + + adap->algo_data = bit_data; + adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + adap->dev.parent = dev; + device_set_node(&adap->dev, fwnode); + + adap->nr = pdev->id; + ret = i2c_bit_add_numbered_bus(adap); + if (ret) + return ret; + + platform_set_drvdata(pdev, priv); + + /* + * FIXME: using global GPIO numbers is not helpful. If/when we + * get accessors to get the actual name of the GPIO line, + * from the descriptor, then provide that instead. + */ + dev_info(dev, "using lines %u (SDA) and %u (SCL%s)\n", + desc_to_gpio(priv->sda), desc_to_gpio(priv->scl), + pdata->scl_is_output_only + ? ", no clock stretching" : ""); + + i2c_gpio_fault_injector_init(pdev); + + return 0; +} + +static void i2c_gpio_remove(struct platform_device *pdev) +{ + struct i2c_gpio_private_data *priv; + struct i2c_adapter *adap; + + i2c_gpio_fault_injector_exit(pdev); + + priv = platform_get_drvdata(pdev); + adap = &priv->adap; + + i2c_del_adapter(adap); +} + +static const struct of_device_id i2c_gpio_dt_ids[] = { + { .compatible = "i2c-gpio", }, + { /* sentinel */ } +}; + +MODULE_DEVICE_TABLE(of, i2c_gpio_dt_ids); + +static const struct acpi_device_id i2c_gpio_acpi_match[] = { + { "LOON0005" }, /* LoongArch */ + { } +}; +MODULE_DEVICE_TABLE(acpi, i2c_gpio_acpi_match); + +static struct platform_driver i2c_gpio_driver = { + .driver = { + .name = "i2c-gpio", + .of_match_table = i2c_gpio_dt_ids, + .acpi_match_table = i2c_gpio_acpi_match, + }, + .probe = i2c_gpio_probe, + .remove_new = i2c_gpio_remove, +}; + +static int __init i2c_gpio_init(void) +{ + int ret; + + ret = platform_driver_register(&i2c_gpio_driver); + if (ret) + printk(KERN_ERR "i2c-gpio: probe failed: %d\n", ret); + + return ret; +} +subsys_initcall(i2c_gpio_init); + +static void __exit i2c_gpio_exit(void) +{ + platform_driver_unregister(&i2c_gpio_driver); +} +module_exit(i2c_gpio_exit); + +MODULE_AUTHOR("Haavard Skinnemoen (Atmel)"); +MODULE_DESCRIPTION("Platform-independent bitbanging I2C driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:i2c-gpio"); diff --git a/drivers/i2c/busses/i2c-gxp.c b/drivers/i2c/busses/i2c-gxp.c new file mode 100644 index 000000000..efafc0528 --- /dev/null +++ b/drivers/i2c/busses/i2c-gxp.c @@ -0,0 +1,608 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (C) 2022 Hewlett-Packard Enterprise Development Company, L.P. */ + +#include <linux/err.h> +#include <linux/io.h> +#include <linux/i2c.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/mfd/syscon.h> + +#define GXP_MAX_I2C_ENGINE 10 +static const char * const gxp_i2c_name[] = { + "gxp-i2c0", "gxp-i2c1", "gxp-i2c2", "gxp-i2c3", + "gxp-i2c4", "gxp-i2c5", "gxp-i2c6", "gxp-i2c7", + "gxp-i2c8", "gxp-i2c9" }; + +/* GXP I2C Global interrupt status/enable register*/ +#define GXP_I2CINTSTAT 0x00 +#define GXP_I2CINTEN 0x04 + +/* GXP I2C registers */ +#define GXP_I2CSTAT 0x00 +#define MASK_STOP_EVENT 0x20 +#define MASK_ACK 0x08 +#define MASK_RW 0x04 +#define GXP_I2CEVTERR 0x01 +#define MASK_SLAVE_CMD_EVENT 0x01 +#define MASK_SLAVE_DATA_EVENT 0x02 +#define MASK_MASTER_EVENT 0x10 +#define GXP_I2CSNPDAT 0x02 +#define GXP_I2CMCMD 0x04 +#define GXP_I2CSCMD 0x06 +#define GXP_I2CSNPAA 0x09 +#define GXP_I2CADVFEAT 0x0A +#define GXP_I2COWNADR 0x0B +#define GXP_I2CFREQDIV 0x0C +#define GXP_I2CFLTFAIR 0x0D +#define GXP_I2CTMOEDG 0x0E +#define GXP_I2CCYCTIM 0x0F + +/* I2CSCMD Bits */ +#define SNOOP_EVT_CLR 0x80 +#define SLAVE_EVT_CLR 0x40 +#define SNOOP_EVT_MASK 0x20 +#define SLAVE_EVT_MASK 0x10 +#define SLAVE_ACK_ENAB 0x08 +#define SLAVE_EVT_STALL 0x01 + +/* I2CMCMD Bits */ +#define MASTER_EVT_CLR 0x80 +#define MASTER_ACK_ENAB 0x08 +#define RW_CMD 0x04 +#define STOP_CMD 0x02 +#define START_CMD 0x01 + +/* I2CTMOEDG value */ +#define GXP_DATA_EDGE_RST_CTRL 0x0a /* 30ns */ + +/* I2CFLTFAIR Bits */ +#define FILTER_CNT 0x30 +#define FAIRNESS_CNT 0x02 + +enum { + GXP_I2C_IDLE = 0, + GXP_I2C_ADDR_PHASE, + GXP_I2C_RDATA_PHASE, + GXP_I2C_WDATA_PHASE, + GXP_I2C_ADDR_NACK, + GXP_I2C_DATA_NACK, + GXP_I2C_ERROR, + GXP_I2C_COMP +}; + +struct gxp_i2c_drvdata { + struct device *dev; + void __iomem *base; + struct i2c_timings t; + u32 engine; + int irq; + struct completion completion; + struct i2c_adapter adapter; + struct i2c_msg *curr_msg; + int msgs_remaining; + int msgs_num; + u8 *buf; + size_t buf_remaining; + unsigned char state; + struct i2c_client *slave; + unsigned char stopped; +}; + +static struct regmap *i2cg_map; + +static void gxp_i2c_start(struct gxp_i2c_drvdata *drvdata) +{ + u16 value; + + drvdata->buf = drvdata->curr_msg->buf; + drvdata->buf_remaining = drvdata->curr_msg->len; + + /* Note: Address in struct i2c_msg is 7 bits */ + value = drvdata->curr_msg->addr << 9; + + /* Read or Write */ + value |= drvdata->curr_msg->flags & I2C_M_RD ? RW_CMD | START_CMD : START_CMD; + + drvdata->state = GXP_I2C_ADDR_PHASE; + writew(value, drvdata->base + GXP_I2CMCMD); +} + +static int gxp_i2c_master_xfer(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num) +{ + int ret; + struct gxp_i2c_drvdata *drvdata = i2c_get_adapdata(adapter); + unsigned long time_left; + + drvdata->msgs_remaining = num; + drvdata->curr_msg = msgs; + drvdata->msgs_num = num; + reinit_completion(&drvdata->completion); + + gxp_i2c_start(drvdata); + + time_left = wait_for_completion_timeout(&drvdata->completion, + adapter->timeout); + ret = num - drvdata->msgs_remaining; + if (time_left == 0) + return -ETIMEDOUT; + + if (drvdata->state == GXP_I2C_ADDR_NACK) + return -ENXIO; + + if (drvdata->state == GXP_I2C_DATA_NACK) + return -EIO; + + return ret; +} + +static u32 gxp_i2c_func(struct i2c_adapter *adap) +{ + if (IS_ENABLED(CONFIG_I2C_SLAVE)) + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SLAVE; + + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +static int gxp_i2c_reg_slave(struct i2c_client *slave) +{ + struct gxp_i2c_drvdata *drvdata = i2c_get_adapdata(slave->adapter); + + if (drvdata->slave) + return -EBUSY; + + if (slave->flags & I2C_CLIENT_TEN) + return -EAFNOSUPPORT; + + drvdata->slave = slave; + + writeb(slave->addr << 1, drvdata->base + GXP_I2COWNADR); + writeb(SLAVE_EVT_CLR | SNOOP_EVT_MASK | SLAVE_ACK_ENAB | + SLAVE_EVT_STALL, drvdata->base + GXP_I2CSCMD); + + return 0; +} + +static int gxp_i2c_unreg_slave(struct i2c_client *slave) +{ + struct gxp_i2c_drvdata *drvdata = i2c_get_adapdata(slave->adapter); + + WARN_ON(!drvdata->slave); + + writeb(0x00, drvdata->base + GXP_I2COWNADR); + writeb(SNOOP_EVT_CLR | SLAVE_EVT_CLR | SNOOP_EVT_MASK | + SLAVE_EVT_MASK, drvdata->base + GXP_I2CSCMD); + + drvdata->slave = NULL; + + return 0; +} +#endif + +static const struct i2c_algorithm gxp_i2c_algo = { + .master_xfer = gxp_i2c_master_xfer, + .functionality = gxp_i2c_func, +#if IS_ENABLED(CONFIG_I2C_SLAVE) + .reg_slave = gxp_i2c_reg_slave, + .unreg_slave = gxp_i2c_unreg_slave, +#endif +}; + +static void gxp_i2c_stop(struct gxp_i2c_drvdata *drvdata) +{ + /* Clear event and send stop */ + writeb(MASTER_EVT_CLR | STOP_CMD, drvdata->base + GXP_I2CMCMD); + + complete(&drvdata->completion); +} + +static void gxp_i2c_restart(struct gxp_i2c_drvdata *drvdata) +{ + u16 value; + + drvdata->buf = drvdata->curr_msg->buf; + drvdata->buf_remaining = drvdata->curr_msg->len; + + value = drvdata->curr_msg->addr << 9; + + if (drvdata->curr_msg->flags & I2C_M_RD) { + /* Read and clear master event */ + value |= MASTER_EVT_CLR | RW_CMD | START_CMD; + } else { + /* Write and clear master event */ + value |= MASTER_EVT_CLR | START_CMD; + } + + drvdata->state = GXP_I2C_ADDR_PHASE; + + writew(value, drvdata->base + GXP_I2CMCMD); +} + +static void gxp_i2c_chk_addr_ack(struct gxp_i2c_drvdata *drvdata) +{ + u16 value; + + value = readb(drvdata->base + GXP_I2CSTAT); + if (!(value & MASK_ACK)) { + /* Got no ack, stop */ + drvdata->state = GXP_I2C_ADDR_NACK; + gxp_i2c_stop(drvdata); + return; + } + + if (drvdata->curr_msg->flags & I2C_M_RD) { + /* Start to read data from slave */ + if (drvdata->buf_remaining == 0) { + /* No more data to read, stop */ + drvdata->msgs_remaining--; + drvdata->state = GXP_I2C_COMP; + gxp_i2c_stop(drvdata); + return; + } + drvdata->state = GXP_I2C_RDATA_PHASE; + + if (drvdata->buf_remaining == 1) { + /* The last data, do not ack */ + writeb(MASTER_EVT_CLR | RW_CMD, + drvdata->base + GXP_I2CMCMD); + } else { + /* Read data and ack it */ + writeb(MASTER_EVT_CLR | MASTER_ACK_ENAB | + RW_CMD, drvdata->base + GXP_I2CMCMD); + } + } else { + /* Start to write first data to slave */ + if (drvdata->buf_remaining == 0) { + /* No more data to write, stop */ + drvdata->msgs_remaining--; + drvdata->state = GXP_I2C_COMP; + gxp_i2c_stop(drvdata); + return; + } + value = *drvdata->buf; + value = value << 8; + /* Clear master event */ + value |= MASTER_EVT_CLR; + drvdata->buf++; + drvdata->buf_remaining--; + drvdata->state = GXP_I2C_WDATA_PHASE; + writew(value, drvdata->base + GXP_I2CMCMD); + } +} + +static void gxp_i2c_ack_data(struct gxp_i2c_drvdata *drvdata) +{ + u8 value; + + /* Store the data returned */ + value = readb(drvdata->base + GXP_I2CSNPDAT); + *drvdata->buf = value; + drvdata->buf++; + drvdata->buf_remaining--; + + if (drvdata->buf_remaining == 0) { + /* No more data, this message is completed. */ + drvdata->msgs_remaining--; + + if (drvdata->msgs_remaining == 0) { + /* No more messages, stop */ + drvdata->state = GXP_I2C_COMP; + gxp_i2c_stop(drvdata); + return; + } + /* Move to next message and start transfer */ + drvdata->curr_msg++; + gxp_i2c_restart(drvdata); + return; + } + + /* Ack the slave to make it send next byte */ + drvdata->state = GXP_I2C_RDATA_PHASE; + if (drvdata->buf_remaining == 1) { + /* The last data, do not ack */ + writeb(MASTER_EVT_CLR | RW_CMD, + drvdata->base + GXP_I2CMCMD); + } else { + /* Read data and ack it */ + writeb(MASTER_EVT_CLR | MASTER_ACK_ENAB | + RW_CMD, drvdata->base + GXP_I2CMCMD); + } +} + +static void gxp_i2c_chk_data_ack(struct gxp_i2c_drvdata *drvdata) +{ + u16 value; + + value = readb(drvdata->base + GXP_I2CSTAT); + if (!(value & MASK_ACK)) { + /* Received No ack, stop */ + drvdata->state = GXP_I2C_DATA_NACK; + gxp_i2c_stop(drvdata); + return; + } + + /* Got ack, check if there is more data to write */ + if (drvdata->buf_remaining == 0) { + /* No more data, this message is completed */ + drvdata->msgs_remaining--; + + if (drvdata->msgs_remaining == 0) { + /* No more messages, stop */ + drvdata->state = GXP_I2C_COMP; + gxp_i2c_stop(drvdata); + return; + } + /* Move to next message and start transfer */ + drvdata->curr_msg++; + gxp_i2c_restart(drvdata); + return; + } + + /* Write data to slave */ + value = *drvdata->buf; + value = value << 8; + + /* Clear master event */ + value |= MASTER_EVT_CLR; + drvdata->buf++; + drvdata->buf_remaining--; + drvdata->state = GXP_I2C_WDATA_PHASE; + writew(value, drvdata->base + GXP_I2CMCMD); +} + +static bool gxp_i2c_slave_irq_handler(struct gxp_i2c_drvdata *drvdata) +{ + u8 value; + u8 buf; + int ret; + + value = readb(drvdata->base + GXP_I2CEVTERR); + + /* Received start or stop event */ + if (value & MASK_SLAVE_CMD_EVENT) { + value = readb(drvdata->base + GXP_I2CSTAT); + /* Master sent stop */ + if (value & MASK_STOP_EVENT) { + if (drvdata->stopped == 0) + i2c_slave_event(drvdata->slave, I2C_SLAVE_STOP, &buf); + writeb(SLAVE_EVT_CLR | SNOOP_EVT_MASK | + SLAVE_ACK_ENAB | SLAVE_EVT_STALL, drvdata->base + GXP_I2CSCMD); + drvdata->stopped = 1; + } else { + /* Master sent start and wants to read */ + drvdata->stopped = 0; + if (value & MASK_RW) { + i2c_slave_event(drvdata->slave, + I2C_SLAVE_READ_REQUESTED, &buf); + value = buf << 8 | (SLAVE_EVT_CLR | SNOOP_EVT_MASK | + SLAVE_EVT_STALL); + writew(value, drvdata->base + GXP_I2CSCMD); + } else { + /* Master wants to write to us */ + ret = i2c_slave_event(drvdata->slave, + I2C_SLAVE_WRITE_REQUESTED, &buf); + if (!ret) { + /* Ack next byte from master */ + writeb(SLAVE_EVT_CLR | SNOOP_EVT_MASK | + SLAVE_ACK_ENAB | SLAVE_EVT_STALL, + drvdata->base + GXP_I2CSCMD); + } else { + /* Nack next byte from master */ + writeb(SLAVE_EVT_CLR | SNOOP_EVT_MASK | + SLAVE_EVT_STALL, drvdata->base + GXP_I2CSCMD); + } + } + } + } else if (value & MASK_SLAVE_DATA_EVENT) { + value = readb(drvdata->base + GXP_I2CSTAT); + /* Master wants to read */ + if (value & MASK_RW) { + /* Master wants another byte */ + if (value & MASK_ACK) { + i2c_slave_event(drvdata->slave, + I2C_SLAVE_READ_PROCESSED, &buf); + value = buf << 8 | (SLAVE_EVT_CLR | SNOOP_EVT_MASK | + SLAVE_EVT_STALL); + writew(value, drvdata->base + GXP_I2CSCMD); + } else { + /* No more bytes needed */ + writew(SLAVE_EVT_CLR | SNOOP_EVT_MASK | + SLAVE_ACK_ENAB | SLAVE_EVT_STALL, + drvdata->base + GXP_I2CSCMD); + } + } else { + /* Master wants to write to us */ + value = readb(drvdata->base + GXP_I2CSNPDAT); + buf = (uint8_t)value; + ret = i2c_slave_event(drvdata->slave, + I2C_SLAVE_WRITE_RECEIVED, &buf); + if (!ret) { + /* Ack next byte from master */ + writeb(SLAVE_EVT_CLR | SNOOP_EVT_MASK | + SLAVE_ACK_ENAB | SLAVE_EVT_STALL, + drvdata->base + GXP_I2CSCMD); + } else { + /* Nack next byte from master */ + writeb(SLAVE_EVT_CLR | SNOOP_EVT_MASK | + SLAVE_EVT_STALL, drvdata->base + GXP_I2CSCMD); + } + } + } else { + return false; + } + + return true; +} + +static irqreturn_t gxp_i2c_irq_handler(int irq, void *_drvdata) +{ + struct gxp_i2c_drvdata *drvdata = (struct gxp_i2c_drvdata *)_drvdata; + u32 value; + + /* Check if the interrupt is for the current engine */ + regmap_read(i2cg_map, GXP_I2CINTSTAT, &value); + if (!(value & BIT(drvdata->engine))) + return IRQ_NONE; + + value = readb(drvdata->base + GXP_I2CEVTERR); + + /* Error */ + if (value & ~(MASK_MASTER_EVENT | MASK_SLAVE_CMD_EVENT | + MASK_SLAVE_DATA_EVENT)) { + /* Clear all events */ + writeb(0x00, drvdata->base + GXP_I2CEVTERR); + drvdata->state = GXP_I2C_ERROR; + gxp_i2c_stop(drvdata); + return IRQ_HANDLED; + } + + if (IS_ENABLED(CONFIG_I2C_SLAVE)) { + /* Slave mode */ + if (value & (MASK_SLAVE_CMD_EVENT | MASK_SLAVE_DATA_EVENT)) { + if (gxp_i2c_slave_irq_handler(drvdata)) + return IRQ_HANDLED; + return IRQ_NONE; + } + } + + /* Master mode */ + switch (drvdata->state) { + case GXP_I2C_ADDR_PHASE: + gxp_i2c_chk_addr_ack(drvdata); + break; + + case GXP_I2C_RDATA_PHASE: + gxp_i2c_ack_data(drvdata); + break; + + case GXP_I2C_WDATA_PHASE: + gxp_i2c_chk_data_ack(drvdata); + break; + } + + return IRQ_HANDLED; +} + +static void gxp_i2c_init(struct gxp_i2c_drvdata *drvdata) +{ + drvdata->state = GXP_I2C_IDLE; + writeb(2000000 / drvdata->t.bus_freq_hz, + drvdata->base + GXP_I2CFREQDIV); + writeb(FILTER_CNT | FAIRNESS_CNT, + drvdata->base + GXP_I2CFLTFAIR); + writeb(GXP_DATA_EDGE_RST_CTRL, drvdata->base + GXP_I2CTMOEDG); + writeb(0x00, drvdata->base + GXP_I2CCYCTIM); + writeb(0x00, drvdata->base + GXP_I2CSNPAA); + writeb(0x00, drvdata->base + GXP_I2CADVFEAT); + writeb(SNOOP_EVT_CLR | SLAVE_EVT_CLR | SNOOP_EVT_MASK | + SLAVE_EVT_MASK, drvdata->base + GXP_I2CSCMD); + writeb(MASTER_EVT_CLR, drvdata->base + GXP_I2CMCMD); + writeb(0x00, drvdata->base + GXP_I2CEVTERR); + writeb(0x00, drvdata->base + GXP_I2COWNADR); +} + +static int gxp_i2c_probe(struct platform_device *pdev) +{ + struct gxp_i2c_drvdata *drvdata; + int rc; + struct i2c_adapter *adapter; + + if (!i2cg_map) { + i2cg_map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, + "hpe,sysreg"); + if (IS_ERR(i2cg_map)) { + return dev_err_probe(&pdev->dev, PTR_ERR(i2cg_map), + "failed to map i2cg_handle\n"); + } + + /* Disable interrupt */ + regmap_update_bits(i2cg_map, GXP_I2CINTEN, 0x00000FFF, 0); + } + + drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), + GFP_KERNEL); + if (!drvdata) + return -ENOMEM; + + platform_set_drvdata(pdev, drvdata); + drvdata->dev = &pdev->dev; + init_completion(&drvdata->completion); + + drvdata->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(drvdata->base)) + return PTR_ERR(drvdata->base); + + /* Use physical memory address to determine which I2C engine this is. */ + drvdata->engine = ((size_t)drvdata->base & 0xf00) >> 8; + + if (drvdata->engine >= GXP_MAX_I2C_ENGINE) { + return dev_err_probe(&pdev->dev, -EINVAL, "i2c engine% is unsupported\n", + drvdata->engine); + } + + rc = platform_get_irq(pdev, 0); + if (rc < 0) + return rc; + + drvdata->irq = rc; + rc = devm_request_irq(&pdev->dev, drvdata->irq, gxp_i2c_irq_handler, + IRQF_SHARED, gxp_i2c_name[drvdata->engine], drvdata); + if (rc < 0) + return dev_err_probe(&pdev->dev, rc, "irq request failed\n"); + + i2c_parse_fw_timings(&pdev->dev, &drvdata->t, true); + + gxp_i2c_init(drvdata); + + /* Enable interrupt */ + regmap_update_bits(i2cg_map, GXP_I2CINTEN, BIT(drvdata->engine), + BIT(drvdata->engine)); + + adapter = &drvdata->adapter; + i2c_set_adapdata(adapter, drvdata); + + adapter->owner = THIS_MODULE; + strscpy(adapter->name, "HPE GXP I2C adapter", sizeof(adapter->name)); + adapter->algo = &gxp_i2c_algo; + adapter->dev.parent = &pdev->dev; + adapter->dev.of_node = pdev->dev.of_node; + + rc = i2c_add_adapter(adapter); + if (rc) + return dev_err_probe(&pdev->dev, rc, "i2c add adapter failed\n"); + + return 0; +} + +static void gxp_i2c_remove(struct platform_device *pdev) +{ + struct gxp_i2c_drvdata *drvdata = platform_get_drvdata(pdev); + + /* Disable interrupt */ + regmap_update_bits(i2cg_map, GXP_I2CINTEN, BIT(drvdata->engine), 0); + i2c_del_adapter(&drvdata->adapter); +} + +static const struct of_device_id gxp_i2c_of_match[] = { + { .compatible = "hpe,gxp-i2c" }, + {}, +}; +MODULE_DEVICE_TABLE(of, gxp_i2c_of_match); + +static struct platform_driver gxp_i2c_driver = { + .probe = gxp_i2c_probe, + .remove_new = gxp_i2c_remove, + .driver = { + .name = "gxp-i2c", + .of_match_table = gxp_i2c_of_match, + }, +}; +module_platform_driver(gxp_i2c_driver); + +MODULE_AUTHOR("Nick Hawkins <nick.hawkins@hpe.com>"); +MODULE_DESCRIPTION("HPE GXP I2C bus driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-highlander.c b/drivers/i2c/busses/i2c-highlander.c new file mode 100644 index 000000000..7922bc917 --- /dev/null +++ b/drivers/i2c/busses/i2c-highlander.c @@ -0,0 +1,476 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Renesas Solutions Highlander FPGA I2C/SMBus support. + * + * Supported devices: R0P7780LC0011RL, R0P7785LC0011RL + * + * Copyright (C) 2008 Paul Mundt + * Copyright (C) 2008 Renesas Solutions Corp. + * Copyright (C) 2008 Atom Create Engineering Co., Ltd. + */ +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/i2c.h> +#include <linux/platform_device.h> +#include <linux/completion.h> +#include <linux/io.h> +#include <linux/delay.h> +#include <linux/slab.h> + +#define SMCR 0x00 +#define SMCR_START (1 << 0) +#define SMCR_IRIC (1 << 1) +#define SMCR_BBSY (1 << 2) +#define SMCR_ACKE (1 << 3) +#define SMCR_RST (1 << 4) +#define SMCR_IEIC (1 << 6) + +#define SMSMADR 0x02 + +#define SMMR 0x04 +#define SMMR_MODE0 (1 << 0) +#define SMMR_MODE1 (1 << 1) +#define SMMR_CAP (1 << 3) +#define SMMR_TMMD (1 << 4) +#define SMMR_SP (1 << 7) + +#define SMSADR 0x06 +#define SMTRDR 0x46 + +struct highlander_i2c_dev { + struct device *dev; + void __iomem *base; + struct i2c_adapter adapter; + struct completion cmd_complete; + unsigned long last_read_time; + int irq; + u8 *buf; + size_t buf_len; +}; + +static bool iic_force_poll, iic_force_normal; +static int iic_timeout = 1000, iic_read_delay; + +static inline void highlander_i2c_irq_enable(struct highlander_i2c_dev *dev) +{ + iowrite16(ioread16(dev->base + SMCR) | SMCR_IEIC, dev->base + SMCR); +} + +static inline void highlander_i2c_irq_disable(struct highlander_i2c_dev *dev) +{ + iowrite16(ioread16(dev->base + SMCR) & ~SMCR_IEIC, dev->base + SMCR); +} + +static inline void highlander_i2c_start(struct highlander_i2c_dev *dev) +{ + iowrite16(ioread16(dev->base + SMCR) | SMCR_START, dev->base + SMCR); +} + +static inline void highlander_i2c_done(struct highlander_i2c_dev *dev) +{ + iowrite16(ioread16(dev->base + SMCR) | SMCR_IRIC, dev->base + SMCR); +} + +static void highlander_i2c_setup(struct highlander_i2c_dev *dev) +{ + u16 smmr; + + smmr = ioread16(dev->base + SMMR); + smmr |= SMMR_TMMD; + + if (iic_force_normal) + smmr &= ~SMMR_SP; + else + smmr |= SMMR_SP; + + iowrite16(smmr, dev->base + SMMR); +} + +static void smbus_write_data(u8 *src, u16 *dst, int len) +{ + for (; len > 1; len -= 2) { + *dst++ = be16_to_cpup((__be16 *)src); + src += 2; + } + + if (len) + *dst = *src << 8; +} + +static void smbus_read_data(u16 *src, u8 *dst, int len) +{ + for (; len > 1; len -= 2) { + *(__be16 *)dst = cpu_to_be16p(src++); + dst += 2; + } + + if (len) + *dst = *src >> 8; +} + +static void highlander_i2c_command(struct highlander_i2c_dev *dev, + u8 command, int len) +{ + unsigned int i; + u16 cmd = (command << 8) | command; + + for (i = 0; i < len; i += 2) { + if (len - i == 1) + cmd = command << 8; + iowrite16(cmd, dev->base + SMSADR + i); + dev_dbg(dev->dev, "command data[%x] 0x%04x\n", i/2, cmd); + } +} + +static int highlander_i2c_wait_for_bbsy(struct highlander_i2c_dev *dev) +{ + unsigned long timeout; + + timeout = jiffies + msecs_to_jiffies(iic_timeout); + while (ioread16(dev->base + SMCR) & SMCR_BBSY) { + if (time_after(jiffies, timeout)) { + dev_warn(dev->dev, "timeout waiting for bus ready\n"); + return -ETIMEDOUT; + } + + msleep(1); + } + + return 0; +} + +static int highlander_i2c_reset(struct highlander_i2c_dev *dev) +{ + iowrite16(ioread16(dev->base + SMCR) | SMCR_RST, dev->base + SMCR); + return highlander_i2c_wait_for_bbsy(dev); +} + +static int highlander_i2c_wait_for_ack(struct highlander_i2c_dev *dev) +{ + u16 tmp = ioread16(dev->base + SMCR); + + if ((tmp & (SMCR_IRIC | SMCR_ACKE)) == SMCR_ACKE) { + dev_warn(dev->dev, "ack abnormality\n"); + return highlander_i2c_reset(dev); + } + + return 0; +} + +static irqreturn_t highlander_i2c_irq(int irq, void *dev_id) +{ + struct highlander_i2c_dev *dev = dev_id; + + highlander_i2c_done(dev); + complete(&dev->cmd_complete); + + return IRQ_HANDLED; +} + +static void highlander_i2c_poll(struct highlander_i2c_dev *dev) +{ + unsigned long timeout; + u16 smcr; + + timeout = jiffies + msecs_to_jiffies(iic_timeout); + for (;;) { + smcr = ioread16(dev->base + SMCR); + + /* + * Don't bother checking ACKE here, this and the reset + * are handled in highlander_i2c_wait_xfer_done() when + * waiting for the ACK. + */ + + if (smcr & SMCR_IRIC) + return; + if (time_after(jiffies, timeout)) + break; + + cpu_relax(); + cond_resched(); + } + + dev_err(dev->dev, "polling timed out\n"); +} + +static inline int highlander_i2c_wait_xfer_done(struct highlander_i2c_dev *dev) +{ + if (dev->irq) + wait_for_completion_timeout(&dev->cmd_complete, + msecs_to_jiffies(iic_timeout)); + else + /* busy looping, the IRQ of champions */ + highlander_i2c_poll(dev); + + return highlander_i2c_wait_for_ack(dev); +} + +static int highlander_i2c_read(struct highlander_i2c_dev *dev) +{ + int i, cnt; + u16 data[16]; + + if (highlander_i2c_wait_for_bbsy(dev)) + return -EAGAIN; + + highlander_i2c_start(dev); + + if (highlander_i2c_wait_xfer_done(dev)) { + dev_err(dev->dev, "Arbitration loss\n"); + return -EAGAIN; + } + + /* + * The R0P7780LC0011RL FPGA needs a significant delay between + * data read cycles, otherwise the transceiver gets confused and + * garbage is returned when the read is subsequently aborted. + * + * It is not sufficient to wait for BBSY. + * + * While this generally only applies to the older SH7780-based + * Highlanders, the same issue can be observed on SH7785 ones, + * albeit less frequently. SH7780-based Highlanders may need + * this to be as high as 1000 ms. + */ + if (iic_read_delay && time_before(jiffies, dev->last_read_time + + msecs_to_jiffies(iic_read_delay))) + msleep(jiffies_to_msecs((dev->last_read_time + + msecs_to_jiffies(iic_read_delay)) - jiffies)); + + cnt = (dev->buf_len + 1) >> 1; + for (i = 0; i < cnt; i++) { + data[i] = ioread16(dev->base + SMTRDR + (i * sizeof(u16))); + dev_dbg(dev->dev, "read data[%x] 0x%04x\n", i, data[i]); + } + + smbus_read_data(data, dev->buf, dev->buf_len); + + dev->last_read_time = jiffies; + + return 0; +} + +static int highlander_i2c_write(struct highlander_i2c_dev *dev) +{ + int i, cnt; + u16 data[16]; + + smbus_write_data(dev->buf, data, dev->buf_len); + + cnt = (dev->buf_len + 1) >> 1; + for (i = 0; i < cnt; i++) { + iowrite16(data[i], dev->base + SMTRDR + (i * sizeof(u16))); + dev_dbg(dev->dev, "write data[%x] 0x%04x\n", i, data[i]); + } + + if (highlander_i2c_wait_for_bbsy(dev)) + return -EAGAIN; + + highlander_i2c_start(dev); + + return highlander_i2c_wait_xfer_done(dev); +} + +static int highlander_i2c_smbus_xfer(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + struct highlander_i2c_dev *dev = i2c_get_adapdata(adap); + u16 tmp; + + init_completion(&dev->cmd_complete); + + dev_dbg(dev->dev, "addr %04x, command %02x, read_write %d, size %d\n", + addr, command, read_write, size); + + /* + * Set up the buffer and transfer size + */ + switch (size) { + case I2C_SMBUS_BYTE_DATA: + dev->buf = &data->byte; + dev->buf_len = 1; + break; + case I2C_SMBUS_I2C_BLOCK_DATA: + dev->buf = &data->block[1]; + dev->buf_len = data->block[0]; + break; + default: + dev_err(dev->dev, "unsupported command %d\n", size); + return -EINVAL; + } + + /* + * Encode the mode setting + */ + tmp = ioread16(dev->base + SMMR); + tmp &= ~(SMMR_MODE0 | SMMR_MODE1); + + switch (dev->buf_len) { + case 1: + /* default */ + break; + case 8: + tmp |= SMMR_MODE0; + break; + case 16: + tmp |= SMMR_MODE1; + break; + case 32: + tmp |= (SMMR_MODE0 | SMMR_MODE1); + break; + default: + dev_err(dev->dev, "unsupported xfer size %zu\n", dev->buf_len); + return -EINVAL; + } + + iowrite16(tmp, dev->base + SMMR); + + /* Ensure we're in a sane state */ + highlander_i2c_done(dev); + + /* Set slave address */ + iowrite16((addr << 1) | read_write, dev->base + SMSMADR); + + highlander_i2c_command(dev, command, dev->buf_len); + + if (read_write == I2C_SMBUS_READ) + return highlander_i2c_read(dev); + else + return highlander_i2c_write(dev); +} + +static u32 highlander_i2c_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK; +} + +static const struct i2c_algorithm highlander_i2c_algo = { + .smbus_xfer = highlander_i2c_smbus_xfer, + .functionality = highlander_i2c_func, +}; + +static int highlander_i2c_probe(struct platform_device *pdev) +{ + struct highlander_i2c_dev *dev; + struct i2c_adapter *adap; + struct resource *res; + int ret; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (unlikely(!res)) { + dev_err(&pdev->dev, "no mem resource\n"); + return -ENODEV; + } + + dev = kzalloc(sizeof(struct highlander_i2c_dev), GFP_KERNEL); + if (unlikely(!dev)) + return -ENOMEM; + + dev->base = ioremap(res->start, resource_size(res)); + if (unlikely(!dev->base)) { + ret = -ENXIO; + goto err; + } + + dev->dev = &pdev->dev; + platform_set_drvdata(pdev, dev); + + dev->irq = platform_get_irq(pdev, 0); + if (dev->irq < 0 || iic_force_poll) + dev->irq = 0; + + if (dev->irq) { + ret = request_irq(dev->irq, highlander_i2c_irq, 0, + pdev->name, dev); + if (unlikely(ret)) + goto err_unmap; + + highlander_i2c_irq_enable(dev); + } else { + dev_notice(&pdev->dev, "no IRQ, using polling mode\n"); + highlander_i2c_irq_disable(dev); + } + + dev->last_read_time = jiffies; /* initial read jiffies */ + + highlander_i2c_setup(dev); + + adap = &dev->adapter; + i2c_set_adapdata(adap, dev); + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_HWMON; + strscpy(adap->name, "HL FPGA I2C adapter", sizeof(adap->name)); + adap->algo = &highlander_i2c_algo; + adap->dev.parent = &pdev->dev; + adap->nr = pdev->id; + + /* + * Reset the adapter + */ + ret = highlander_i2c_reset(dev); + if (unlikely(ret)) { + dev_err(&pdev->dev, "controller didn't come up\n"); + goto err_free_irq; + } + + ret = i2c_add_numbered_adapter(adap); + if (unlikely(ret)) { + dev_err(&pdev->dev, "failure adding adapter\n"); + goto err_free_irq; + } + + return 0; + +err_free_irq: + if (dev->irq) + free_irq(dev->irq, dev); +err_unmap: + iounmap(dev->base); +err: + kfree(dev); + + return ret; +} + +static void highlander_i2c_remove(struct platform_device *pdev) +{ + struct highlander_i2c_dev *dev = platform_get_drvdata(pdev); + + i2c_del_adapter(&dev->adapter); + + if (dev->irq) + free_irq(dev->irq, dev); + + iounmap(dev->base); + kfree(dev); +} + +static struct platform_driver highlander_i2c_driver = { + .driver = { + .name = "i2c-highlander", + }, + + .probe = highlander_i2c_probe, + .remove_new = highlander_i2c_remove, +}; + +module_platform_driver(highlander_i2c_driver); + +MODULE_AUTHOR("Paul Mundt"); +MODULE_DESCRIPTION("Renesas Highlander FPGA I2C/SMBus adapter"); +MODULE_LICENSE("GPL v2"); + +module_param(iic_force_poll, bool, 0); +module_param(iic_force_normal, bool, 0); +module_param(iic_timeout, int, 0); +module_param(iic_read_delay, int, 0); + +MODULE_PARM_DESC(iic_force_poll, "Force polling mode"); +MODULE_PARM_DESC(iic_force_normal, + "Force normal mode (100 kHz), default is fast mode (400 kHz)"); +MODULE_PARM_DESC(iic_timeout, "Set timeout value in msecs (default 1000 ms)"); +MODULE_PARM_DESC(iic_read_delay, + "Delay between data read cycles (default 0 ms)"); diff --git a/drivers/i2c/busses/i2c-hisi.c b/drivers/i2c/busses/i2c-hisi.c new file mode 100644 index 000000000..dfad5bad5 --- /dev/null +++ b/drivers/i2c/busses/i2c-hisi.c @@ -0,0 +1,532 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * HiSilicon I2C Controller Driver for Kunpeng SoC + * + * Copyright (c) 2021 HiSilicon Technologies Co., Ltd. + */ + +#include <linux/bits.h> +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/platform_device.h> +#include <linux/property.h> +#include <linux/units.h> + +#define HISI_I2C_FRAME_CTRL 0x0000 +#define HISI_I2C_FRAME_CTRL_SPEED_MODE GENMASK(1, 0) +#define HISI_I2C_FRAME_CTRL_ADDR_TEN BIT(2) +#define HISI_I2C_SLV_ADDR 0x0004 +#define HISI_I2C_SLV_ADDR_VAL GENMASK(9, 0) +#define HISI_I2C_SLV_ADDR_GC_S_MODE BIT(10) +#define HISI_I2C_SLV_ADDR_GC_S_EN BIT(11) +#define HISI_I2C_CMD_TXDATA 0x0008 +#define HISI_I2C_CMD_TXDATA_DATA GENMASK(7, 0) +#define HISI_I2C_CMD_TXDATA_RW BIT(8) +#define HISI_I2C_CMD_TXDATA_P_EN BIT(9) +#define HISI_I2C_CMD_TXDATA_SR_EN BIT(10) +#define HISI_I2C_RXDATA 0x000c +#define HISI_I2C_RXDATA_DATA GENMASK(7, 0) +#define HISI_I2C_SS_SCL_HCNT 0x0010 +#define HISI_I2C_SS_SCL_LCNT 0x0014 +#define HISI_I2C_FS_SCL_HCNT 0x0018 +#define HISI_I2C_FS_SCL_LCNT 0x001c +#define HISI_I2C_HS_SCL_HCNT 0x0020 +#define HISI_I2C_HS_SCL_LCNT 0x0024 +#define HISI_I2C_FIFO_CTRL 0x0028 +#define HISI_I2C_FIFO_RX_CLR BIT(0) +#define HISI_I2C_FIFO_TX_CLR BIT(1) +#define HISI_I2C_FIFO_RX_AF_THRESH GENMASK(7, 2) +#define HISI_I2C_FIFO_TX_AE_THRESH GENMASK(13, 8) +#define HISI_I2C_FIFO_STATE 0x002c +#define HISI_I2C_FIFO_STATE_RX_RERR BIT(0) +#define HISI_I2C_FIFO_STATE_RX_WERR BIT(1) +#define HISI_I2C_FIFO_STATE_RX_EMPTY BIT(3) +#define HISI_I2C_FIFO_STATE_TX_RERR BIT(6) +#define HISI_I2C_FIFO_STATE_TX_WERR BIT(7) +#define HISI_I2C_FIFO_STATE_TX_FULL BIT(11) +#define HISI_I2C_SDA_HOLD 0x0030 +#define HISI_I2C_SDA_HOLD_TX GENMASK(15, 0) +#define HISI_I2C_SDA_HOLD_RX GENMASK(23, 16) +#define HISI_I2C_FS_SPK_LEN 0x0038 +#define HISI_I2C_FS_SPK_LEN_CNT GENMASK(7, 0) +#define HISI_I2C_HS_SPK_LEN 0x003c +#define HISI_I2C_HS_SPK_LEN_CNT GENMASK(7, 0) +#define HISI_I2C_INT_MSTAT 0x0044 +#define HISI_I2C_INT_CLR 0x0048 +#define HISI_I2C_INT_MASK 0x004C +#define HISI_I2C_TRANS_STATE 0x0050 +#define HISI_I2C_TRANS_ERR 0x0054 +#define HISI_I2C_VERSION 0x0058 + +#define HISI_I2C_INT_ALL GENMASK(4, 0) +#define HISI_I2C_INT_TRANS_CPLT BIT(0) +#define HISI_I2C_INT_TRANS_ERR BIT(1) +#define HISI_I2C_INT_FIFO_ERR BIT(2) +#define HISI_I2C_INT_RX_FULL BIT(3) +#define HISI_I2C_INT_TX_EMPTY BIT(4) +#define HISI_I2C_INT_ERR \ + (HISI_I2C_INT_TRANS_ERR | HISI_I2C_INT_FIFO_ERR) + +#define HISI_I2C_STD_SPEED_MODE 0 +#define HISI_I2C_FAST_SPEED_MODE 1 +#define HISI_I2C_HIGH_SPEED_MODE 2 + +#define HISI_I2C_TX_FIFO_DEPTH 64 +#define HISI_I2C_RX_FIFO_DEPTH 64 +#define HISI_I2C_TX_F_AE_THRESH 1 +#define HISI_I2C_RX_F_AF_THRESH 60 + +#define NSEC_TO_CYCLES(ns, clk_rate_khz) \ + DIV_ROUND_UP_ULL((clk_rate_khz) * (ns), NSEC_PER_MSEC) + +struct hisi_i2c_controller { + struct i2c_adapter adapter; + void __iomem *iobase; + struct device *dev; + struct clk *clk; + int irq; + + /* Intermediates for recording the transfer process */ + struct completion *completion; + struct i2c_msg *msgs; + int msg_num; + int msg_tx_idx; + int buf_tx_idx; + int msg_rx_idx; + int buf_rx_idx; + u16 tar_addr; + u32 xfer_err; + + /* I2C bus configuration */ + struct i2c_timings t; + u32 clk_rate_khz; + u32 spk_len; +}; + +static void hisi_i2c_enable_int(struct hisi_i2c_controller *ctlr, u32 mask) +{ + writel_relaxed(mask, ctlr->iobase + HISI_I2C_INT_MASK); +} + +static void hisi_i2c_disable_int(struct hisi_i2c_controller *ctlr, u32 mask) +{ + writel_relaxed((~mask) & HISI_I2C_INT_ALL, ctlr->iobase + HISI_I2C_INT_MASK); +} + +static void hisi_i2c_clear_int(struct hisi_i2c_controller *ctlr, u32 mask) +{ + writel_relaxed(mask, ctlr->iobase + HISI_I2C_INT_CLR); +} + +static void hisi_i2c_handle_errors(struct hisi_i2c_controller *ctlr) +{ + u32 int_err = ctlr->xfer_err, reg; + + if (int_err & HISI_I2C_INT_FIFO_ERR) { + reg = readl(ctlr->iobase + HISI_I2C_FIFO_STATE); + + if (reg & HISI_I2C_FIFO_STATE_RX_RERR) + dev_err(ctlr->dev, "rx fifo error read\n"); + + if (reg & HISI_I2C_FIFO_STATE_RX_WERR) + dev_err(ctlr->dev, "rx fifo error write\n"); + + if (reg & HISI_I2C_FIFO_STATE_TX_RERR) + dev_err(ctlr->dev, "tx fifo error read\n"); + + if (reg & HISI_I2C_FIFO_STATE_TX_WERR) + dev_err(ctlr->dev, "tx fifo error write\n"); + } +} + +static int hisi_i2c_start_xfer(struct hisi_i2c_controller *ctlr) +{ + struct i2c_msg *msg = ctlr->msgs; + u32 reg; + + reg = readl(ctlr->iobase + HISI_I2C_FRAME_CTRL); + reg &= ~HISI_I2C_FRAME_CTRL_ADDR_TEN; + if (msg->flags & I2C_M_TEN) + reg |= HISI_I2C_FRAME_CTRL_ADDR_TEN; + writel(reg, ctlr->iobase + HISI_I2C_FRAME_CTRL); + + reg = readl(ctlr->iobase + HISI_I2C_SLV_ADDR); + reg &= ~HISI_I2C_SLV_ADDR_VAL; + reg |= FIELD_PREP(HISI_I2C_SLV_ADDR_VAL, msg->addr); + writel(reg, ctlr->iobase + HISI_I2C_SLV_ADDR); + + reg = readl(ctlr->iobase + HISI_I2C_FIFO_CTRL); + reg |= HISI_I2C_FIFO_RX_CLR | HISI_I2C_FIFO_TX_CLR; + writel(reg, ctlr->iobase + HISI_I2C_FIFO_CTRL); + reg &= ~(HISI_I2C_FIFO_RX_CLR | HISI_I2C_FIFO_TX_CLR); + writel(reg, ctlr->iobase + HISI_I2C_FIFO_CTRL); + + hisi_i2c_clear_int(ctlr, HISI_I2C_INT_ALL); + hisi_i2c_enable_int(ctlr, HISI_I2C_INT_ALL); + + return 0; +} + +static void hisi_i2c_reset_xfer(struct hisi_i2c_controller *ctlr) +{ + ctlr->msg_num = 0; + ctlr->xfer_err = 0; + ctlr->msg_tx_idx = 0; + ctlr->msg_rx_idx = 0; + ctlr->buf_tx_idx = 0; + ctlr->buf_rx_idx = 0; +} + +/* + * Initialize the transfer information and start the I2C bus transfer. + * We only configure the transfer and do some pre/post works here, and + * wait for the transfer done. The major transfer process is performed + * in the IRQ handler. + */ +static int hisi_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct hisi_i2c_controller *ctlr = i2c_get_adapdata(adap); + DECLARE_COMPLETION_ONSTACK(done); + int ret = num; + + hisi_i2c_reset_xfer(ctlr); + ctlr->completion = &done; + ctlr->msg_num = num; + ctlr->msgs = msgs; + + hisi_i2c_start_xfer(ctlr); + + if (!wait_for_completion_timeout(ctlr->completion, adap->timeout)) { + hisi_i2c_disable_int(ctlr, HISI_I2C_INT_ALL); + synchronize_irq(ctlr->irq); + i2c_recover_bus(&ctlr->adapter); + dev_err(ctlr->dev, "bus transfer timeout\n"); + ret = -EIO; + } + + if (ctlr->xfer_err) { + hisi_i2c_handle_errors(ctlr); + ret = -EIO; + } + + hisi_i2c_reset_xfer(ctlr); + ctlr->completion = NULL; + + return ret; +} + +static u32 hisi_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm hisi_i2c_algo = { + .master_xfer = hisi_i2c_master_xfer, + .functionality = hisi_i2c_functionality, +}; + +static int hisi_i2c_read_rx_fifo(struct hisi_i2c_controller *ctlr) +{ + struct i2c_msg *cur_msg; + u32 fifo_state; + + while (ctlr->msg_rx_idx < ctlr->msg_num) { + cur_msg = ctlr->msgs + ctlr->msg_rx_idx; + + if (!(cur_msg->flags & I2C_M_RD)) { + ctlr->msg_rx_idx++; + continue; + } + + fifo_state = readl(ctlr->iobase + HISI_I2C_FIFO_STATE); + while (!(fifo_state & HISI_I2C_FIFO_STATE_RX_EMPTY) && + ctlr->buf_rx_idx < cur_msg->len) { + cur_msg->buf[ctlr->buf_rx_idx++] = readl(ctlr->iobase + HISI_I2C_RXDATA); + fifo_state = readl(ctlr->iobase + HISI_I2C_FIFO_STATE); + } + + if (ctlr->buf_rx_idx == cur_msg->len) { + ctlr->buf_rx_idx = 0; + ctlr->msg_rx_idx++; + } + + if (fifo_state & HISI_I2C_FIFO_STATE_RX_EMPTY) + break; + } + + return 0; +} + +static void hisi_i2c_xfer_msg(struct hisi_i2c_controller *ctlr) +{ + int max_write = HISI_I2C_TX_FIFO_DEPTH; + bool need_restart = false, last_msg; + struct i2c_msg *cur_msg; + u32 cmd, fifo_state; + + while (ctlr->msg_tx_idx < ctlr->msg_num) { + cur_msg = ctlr->msgs + ctlr->msg_tx_idx; + last_msg = (ctlr->msg_tx_idx == ctlr->msg_num - 1); + + /* Signal the SR bit when we start transferring a new message */ + if (ctlr->msg_tx_idx && !ctlr->buf_tx_idx) + need_restart = true; + + fifo_state = readl(ctlr->iobase + HISI_I2C_FIFO_STATE); + while (!(fifo_state & HISI_I2C_FIFO_STATE_TX_FULL) && + ctlr->buf_tx_idx < cur_msg->len && max_write) { + cmd = 0; + + if (need_restart) { + cmd |= HISI_I2C_CMD_TXDATA_SR_EN; + need_restart = false; + } + + /* Signal the STOP bit at the last frame of the last message */ + if (ctlr->buf_tx_idx == cur_msg->len - 1 && last_msg) + cmd |= HISI_I2C_CMD_TXDATA_P_EN; + + if (cur_msg->flags & I2C_M_RD) + cmd |= HISI_I2C_CMD_TXDATA_RW; + else + cmd |= FIELD_PREP(HISI_I2C_CMD_TXDATA_DATA, + cur_msg->buf[ctlr->buf_tx_idx]); + + writel(cmd, ctlr->iobase + HISI_I2C_CMD_TXDATA); + ctlr->buf_tx_idx++; + max_write--; + + fifo_state = readl(ctlr->iobase + HISI_I2C_FIFO_STATE); + } + + /* Update the transfer index after per message transfer is done. */ + if (ctlr->buf_tx_idx == cur_msg->len) { + ctlr->buf_tx_idx = 0; + ctlr->msg_tx_idx++; + } + + if ((fifo_state & HISI_I2C_FIFO_STATE_TX_FULL) || + max_write == 0) + break; + } + + /* + * Disable the TX_EMPTY interrupt after finishing all the messages to + * avoid overwhelming the CPU. + */ + if (ctlr->msg_tx_idx == ctlr->msg_num) + hisi_i2c_disable_int(ctlr, HISI_I2C_INT_TX_EMPTY); +} + +static irqreturn_t hisi_i2c_irq(int irq, void *context) +{ + struct hisi_i2c_controller *ctlr = context; + u32 int_stat; + + /* + * Don't handle the interrupt if cltr->completion is NULL. We may + * reach here because the interrupt is spurious or the transfer is + * started by another port (e.g. firmware) rather than us. + */ + if (!ctlr->completion) + return IRQ_NONE; + + int_stat = readl(ctlr->iobase + HISI_I2C_INT_MSTAT); + hisi_i2c_clear_int(ctlr, int_stat); + if (!(int_stat & HISI_I2C_INT_ALL)) + return IRQ_NONE; + + if (int_stat & HISI_I2C_INT_TX_EMPTY) + hisi_i2c_xfer_msg(ctlr); + + if (int_stat & HISI_I2C_INT_ERR) { + ctlr->xfer_err = int_stat; + goto out; + } + + /* Drain the rx fifo before finish the transfer */ + if (int_stat & (HISI_I2C_INT_TRANS_CPLT | HISI_I2C_INT_RX_FULL)) + hisi_i2c_read_rx_fifo(ctlr); + +out: + /* + * Only use TRANS_CPLT to indicate the completion. On error cases we'll + * get two interrupts, INT_ERR first then TRANS_CPLT. + */ + if (int_stat & HISI_I2C_INT_TRANS_CPLT) { + hisi_i2c_disable_int(ctlr, HISI_I2C_INT_ALL); + hisi_i2c_clear_int(ctlr, HISI_I2C_INT_ALL); + complete(ctlr->completion); + } + + return IRQ_HANDLED; +} + +/* + * Helper function for calculating and configuring the HIGH and LOW + * periods of SCL clock. The caller will pass the ratio of the + * counts (divide / divisor) according to the target speed mode, + * and the target registers. + */ +static void hisi_i2c_set_scl(struct hisi_i2c_controller *ctlr, + u32 divide, u32 divisor, + u32 reg_hcnt, u32 reg_lcnt) +{ + u32 total_cnt, t_scl_hcnt, t_scl_lcnt, scl_fall_cnt, scl_rise_cnt; + u32 scl_hcnt, scl_lcnt; + + /* Total SCL clock cycles per speed period */ + total_cnt = DIV_ROUND_UP_ULL(ctlr->clk_rate_khz * HZ_PER_KHZ, ctlr->t.bus_freq_hz); + /* Total HIGH level SCL clock cycles including edges */ + t_scl_hcnt = DIV_ROUND_UP_ULL(total_cnt * divide, divisor); + /* Total LOW level SCL clock cycles including edges */ + t_scl_lcnt = total_cnt - t_scl_hcnt; + /* Fall edge SCL clock cycles */ + scl_fall_cnt = NSEC_TO_CYCLES(ctlr->t.scl_fall_ns, ctlr->clk_rate_khz); + /* Rise edge SCL clock cycles */ + scl_rise_cnt = NSEC_TO_CYCLES(ctlr->t.scl_rise_ns, ctlr->clk_rate_khz); + + /* Calculated HIGH and LOW periods of SCL clock */ + scl_hcnt = t_scl_hcnt - ctlr->spk_len - 7 - scl_fall_cnt; + scl_lcnt = t_scl_lcnt - 1 - scl_rise_cnt; + + writel(scl_hcnt, ctlr->iobase + reg_hcnt); + writel(scl_lcnt, ctlr->iobase + reg_lcnt); +} + +static void hisi_i2c_configure_bus(struct hisi_i2c_controller *ctlr) +{ + u32 reg, sda_hold_cnt, speed_mode; + + i2c_parse_fw_timings(ctlr->dev, &ctlr->t, true); + ctlr->spk_len = NSEC_TO_CYCLES(ctlr->t.digital_filter_width_ns, ctlr->clk_rate_khz); + + switch (ctlr->t.bus_freq_hz) { + case I2C_MAX_FAST_MODE_FREQ: + speed_mode = HISI_I2C_FAST_SPEED_MODE; + hisi_i2c_set_scl(ctlr, 26, 76, HISI_I2C_FS_SCL_HCNT, HISI_I2C_FS_SCL_LCNT); + break; + case I2C_MAX_HIGH_SPEED_MODE_FREQ: + speed_mode = HISI_I2C_HIGH_SPEED_MODE; + hisi_i2c_set_scl(ctlr, 6, 22, HISI_I2C_HS_SCL_HCNT, HISI_I2C_HS_SCL_LCNT); + break; + case I2C_MAX_STANDARD_MODE_FREQ: + default: + speed_mode = HISI_I2C_STD_SPEED_MODE; + + /* For default condition force the bus speed to standard mode. */ + ctlr->t.bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ; + hisi_i2c_set_scl(ctlr, 40, 87, HISI_I2C_SS_SCL_HCNT, HISI_I2C_SS_SCL_LCNT); + break; + } + + reg = readl(ctlr->iobase + HISI_I2C_FRAME_CTRL); + reg &= ~HISI_I2C_FRAME_CTRL_SPEED_MODE; + reg |= FIELD_PREP(HISI_I2C_FRAME_CTRL_SPEED_MODE, speed_mode); + writel(reg, ctlr->iobase + HISI_I2C_FRAME_CTRL); + + sda_hold_cnt = NSEC_TO_CYCLES(ctlr->t.sda_hold_ns, ctlr->clk_rate_khz); + + reg = FIELD_PREP(HISI_I2C_SDA_HOLD_TX, sda_hold_cnt); + writel(reg, ctlr->iobase + HISI_I2C_SDA_HOLD); + + writel(ctlr->spk_len, ctlr->iobase + HISI_I2C_FS_SPK_LEN); + + reg = FIELD_PREP(HISI_I2C_FIFO_RX_AF_THRESH, HISI_I2C_RX_F_AF_THRESH); + reg |= FIELD_PREP(HISI_I2C_FIFO_TX_AE_THRESH, HISI_I2C_TX_F_AE_THRESH); + writel(reg, ctlr->iobase + HISI_I2C_FIFO_CTRL); +} + +static int hisi_i2c_probe(struct platform_device *pdev) +{ + struct hisi_i2c_controller *ctlr; + struct device *dev = &pdev->dev; + struct i2c_adapter *adapter; + u64 clk_rate_hz; + u32 hw_version; + int ret; + + ctlr = devm_kzalloc(dev, sizeof(*ctlr), GFP_KERNEL); + if (!ctlr) + return -ENOMEM; + + ctlr->iobase = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(ctlr->iobase)) + return PTR_ERR(ctlr->iobase); + + ctlr->irq = platform_get_irq(pdev, 0); + if (ctlr->irq < 0) + return ctlr->irq; + + ctlr->dev = dev; + + hisi_i2c_disable_int(ctlr, HISI_I2C_INT_ALL); + + ret = devm_request_irq(dev, ctlr->irq, hisi_i2c_irq, 0, "hisi-i2c", ctlr); + if (ret) + return dev_err_probe(dev, ret, "failed to request irq handler\n"); + + ctlr->clk = devm_clk_get_optional_enabled(&pdev->dev, NULL); + if (IS_ERR_OR_NULL(ctlr->clk)) { + ret = device_property_read_u64(dev, "clk_rate", &clk_rate_hz); + if (ret) + return dev_err_probe(dev, ret, "failed to get clock frequency\n"); + } else { + clk_rate_hz = clk_get_rate(ctlr->clk); + } + + ctlr->clk_rate_khz = DIV_ROUND_UP_ULL(clk_rate_hz, HZ_PER_KHZ); + + hisi_i2c_configure_bus(ctlr); + + adapter = &ctlr->adapter; + snprintf(adapter->name, sizeof(adapter->name), + "HiSilicon I2C Controller %s", dev_name(dev)); + adapter->owner = THIS_MODULE; + adapter->algo = &hisi_i2c_algo; + adapter->dev.parent = dev; + i2c_set_adapdata(adapter, ctlr); + + ret = devm_i2c_add_adapter(dev, adapter); + if (ret) + return ret; + + hw_version = readl(ctlr->iobase + HISI_I2C_VERSION); + dev_info(ctlr->dev, "speed mode is %s. hw version 0x%x\n", + i2c_freq_mode_string(ctlr->t.bus_freq_hz), hw_version); + + return 0; +} + +static const struct acpi_device_id hisi_i2c_acpi_ids[] = { + { "HISI03D1", 0 }, + { } +}; +MODULE_DEVICE_TABLE(acpi, hisi_i2c_acpi_ids); + +static const struct of_device_id hisi_i2c_dts_ids[] = { + { .compatible = "hisilicon,ascend910-i2c", }, + { } +}; +MODULE_DEVICE_TABLE(of, hisi_i2c_dts_ids); + +static struct platform_driver hisi_i2c_driver = { + .probe = hisi_i2c_probe, + .driver = { + .name = "hisi-i2c", + .acpi_match_table = hisi_i2c_acpi_ids, + .of_match_table = hisi_i2c_dts_ids, + }, +}; +module_platform_driver(hisi_i2c_driver); + +MODULE_AUTHOR("Yicong Yang <yangyicong@hisilicon.com>"); +MODULE_DESCRIPTION("HiSilicon I2C Controller Driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-hix5hd2.c b/drivers/i2c/busses/i2c-hix5hd2.c new file mode 100644 index 000000000..8e75515c3 --- /dev/null +++ b/drivers/i2c/busses/i2c-hix5hd2.c @@ -0,0 +1,524 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2014 Linaro Ltd. + * Copyright (c) 2014 HiSilicon Limited. + * + * Now only support 7 bit address. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/io.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> + +/* Register Map */ +#define HIX5I2C_CTRL 0x00 +#define HIX5I2C_COM 0x04 +#define HIX5I2C_ICR 0x08 +#define HIX5I2C_SR 0x0c +#define HIX5I2C_SCL_H 0x10 +#define HIX5I2C_SCL_L 0x14 +#define HIX5I2C_TXR 0x18 +#define HIX5I2C_RXR 0x1c + +/* I2C_CTRL_REG */ +#define I2C_ENABLE BIT(8) +#define I2C_UNMASK_TOTAL BIT(7) +#define I2C_UNMASK_START BIT(6) +#define I2C_UNMASK_END BIT(5) +#define I2C_UNMASK_SEND BIT(4) +#define I2C_UNMASK_RECEIVE BIT(3) +#define I2C_UNMASK_ACK BIT(2) +#define I2C_UNMASK_ARBITRATE BIT(1) +#define I2C_UNMASK_OVER BIT(0) +#define I2C_UNMASK_ALL (I2C_UNMASK_ACK | I2C_UNMASK_OVER) + +/* I2C_COM_REG */ +#define I2C_NO_ACK BIT(4) +#define I2C_START BIT(3) +#define I2C_READ BIT(2) +#define I2C_WRITE BIT(1) +#define I2C_STOP BIT(0) + +/* I2C_ICR_REG */ +#define I2C_CLEAR_START BIT(6) +#define I2C_CLEAR_END BIT(5) +#define I2C_CLEAR_SEND BIT(4) +#define I2C_CLEAR_RECEIVE BIT(3) +#define I2C_CLEAR_ACK BIT(2) +#define I2C_CLEAR_ARBITRATE BIT(1) +#define I2C_CLEAR_OVER BIT(0) +#define I2C_CLEAR_ALL (I2C_CLEAR_START | I2C_CLEAR_END | \ + I2C_CLEAR_SEND | I2C_CLEAR_RECEIVE | \ + I2C_CLEAR_ACK | I2C_CLEAR_ARBITRATE | \ + I2C_CLEAR_OVER) + +/* I2C_SR_REG */ +#define I2C_BUSY BIT(7) +#define I2C_START_INTR BIT(6) +#define I2C_END_INTR BIT(5) +#define I2C_SEND_INTR BIT(4) +#define I2C_RECEIVE_INTR BIT(3) +#define I2C_ACK_INTR BIT(2) +#define I2C_ARBITRATE_INTR BIT(1) +#define I2C_OVER_INTR BIT(0) + +enum hix5hd2_i2c_state { + HIX5I2C_STAT_RW_ERR = -1, + HIX5I2C_STAT_INIT, + HIX5I2C_STAT_RW, + HIX5I2C_STAT_SND_STOP, + HIX5I2C_STAT_RW_SUCCESS, +}; + +struct hix5hd2_i2c_priv { + struct i2c_adapter adap; + struct i2c_msg *msg; + struct completion msg_complete; + unsigned int msg_idx; + unsigned int msg_len; + int stop; + void __iomem *regs; + struct clk *clk; + struct device *dev; + spinlock_t lock; /* IRQ synchronization */ + int err; + unsigned int freq; + enum hix5hd2_i2c_state state; +}; + +static u32 hix5hd2_i2c_clr_pend_irq(struct hix5hd2_i2c_priv *priv) +{ + u32 val = readl_relaxed(priv->regs + HIX5I2C_SR); + + writel_relaxed(val, priv->regs + HIX5I2C_ICR); + + return val; +} + +static void hix5hd2_i2c_clr_all_irq(struct hix5hd2_i2c_priv *priv) +{ + writel_relaxed(I2C_CLEAR_ALL, priv->regs + HIX5I2C_ICR); +} + +static void hix5hd2_i2c_disable_irq(struct hix5hd2_i2c_priv *priv) +{ + writel_relaxed(0, priv->regs + HIX5I2C_CTRL); +} + +static void hix5hd2_i2c_enable_irq(struct hix5hd2_i2c_priv *priv) +{ + writel_relaxed(I2C_ENABLE | I2C_UNMASK_TOTAL | I2C_UNMASK_ALL, + priv->regs + HIX5I2C_CTRL); +} + +static void hix5hd2_i2c_drv_setrate(struct hix5hd2_i2c_priv *priv) +{ + u32 rate, val; + u32 scl, sysclock; + + /* close all i2c interrupt */ + val = readl_relaxed(priv->regs + HIX5I2C_CTRL); + writel_relaxed(val & (~I2C_UNMASK_TOTAL), priv->regs + HIX5I2C_CTRL); + + rate = priv->freq; + sysclock = clk_get_rate(priv->clk); + scl = (sysclock / (rate * 2)) / 2 - 1; + writel_relaxed(scl, priv->regs + HIX5I2C_SCL_H); + writel_relaxed(scl, priv->regs + HIX5I2C_SCL_L); + + /* restore original interrupt*/ + writel_relaxed(val, priv->regs + HIX5I2C_CTRL); + + dev_dbg(priv->dev, "%s: sysclock=%d, rate=%d, scl=%d\n", + __func__, sysclock, rate, scl); +} + +static void hix5hd2_i2c_init(struct hix5hd2_i2c_priv *priv) +{ + hix5hd2_i2c_disable_irq(priv); + hix5hd2_i2c_drv_setrate(priv); + hix5hd2_i2c_clr_all_irq(priv); + hix5hd2_i2c_enable_irq(priv); +} + +static void hix5hd2_i2c_reset(struct hix5hd2_i2c_priv *priv) +{ + clk_disable_unprepare(priv->clk); + msleep(20); + clk_prepare_enable(priv->clk); + hix5hd2_i2c_init(priv); +} + +static int hix5hd2_i2c_wait_bus_idle(struct hix5hd2_i2c_priv *priv) +{ + unsigned long stop_time; + u32 int_status; + + /* wait for 100 milli seconds for the bus to be idle */ + stop_time = jiffies + msecs_to_jiffies(100); + do { + int_status = hix5hd2_i2c_clr_pend_irq(priv); + if (!(int_status & I2C_BUSY)) + return 0; + + usleep_range(50, 200); + } while (time_before(jiffies, stop_time)); + + return -EBUSY; +} + +static void hix5hd2_rw_over(struct hix5hd2_i2c_priv *priv) +{ + if (priv->state == HIX5I2C_STAT_SND_STOP) + dev_dbg(priv->dev, "%s: rw and send stop over\n", __func__); + else + dev_dbg(priv->dev, "%s: have not data to send\n", __func__); + + priv->state = HIX5I2C_STAT_RW_SUCCESS; + priv->err = 0; +} + +static void hix5hd2_rw_handle_stop(struct hix5hd2_i2c_priv *priv) +{ + if (priv->stop) { + priv->state = HIX5I2C_STAT_SND_STOP; + writel_relaxed(I2C_STOP, priv->regs + HIX5I2C_COM); + } else { + hix5hd2_rw_over(priv); + } +} + +static void hix5hd2_read_handle(struct hix5hd2_i2c_priv *priv) +{ + if (priv->msg_len == 1) { + /* the last byte don't need send ACK */ + writel_relaxed(I2C_READ | I2C_NO_ACK, priv->regs + HIX5I2C_COM); + } else if (priv->msg_len > 1) { + /* if i2c master receive data will send ACK */ + writel_relaxed(I2C_READ, priv->regs + HIX5I2C_COM); + } else { + hix5hd2_rw_handle_stop(priv); + } +} + +static void hix5hd2_write_handle(struct hix5hd2_i2c_priv *priv) +{ + u8 data; + + if (priv->msg_len > 0) { + data = priv->msg->buf[priv->msg_idx++]; + writel_relaxed(data, priv->regs + HIX5I2C_TXR); + writel_relaxed(I2C_WRITE, priv->regs + HIX5I2C_COM); + } else { + hix5hd2_rw_handle_stop(priv); + } +} + +static int hix5hd2_rw_preprocess(struct hix5hd2_i2c_priv *priv) +{ + u8 data; + + if (priv->state == HIX5I2C_STAT_INIT) { + priv->state = HIX5I2C_STAT_RW; + } else if (priv->state == HIX5I2C_STAT_RW) { + if (priv->msg->flags & I2C_M_RD) { + data = readl_relaxed(priv->regs + HIX5I2C_RXR); + priv->msg->buf[priv->msg_idx++] = data; + } + priv->msg_len--; + } else { + dev_dbg(priv->dev, "%s: error: priv->state = %d, msg_len = %d\n", + __func__, priv->state, priv->msg_len); + return -EAGAIN; + } + return 0; +} + +static irqreturn_t hix5hd2_i2c_irq(int irqno, void *dev_id) +{ + struct hix5hd2_i2c_priv *priv = dev_id; + u32 int_status; + int ret; + + spin_lock(&priv->lock); + + int_status = hix5hd2_i2c_clr_pend_irq(priv); + + /* handle error */ + if (int_status & I2C_ARBITRATE_INTR) { + /* bus error */ + dev_dbg(priv->dev, "ARB bus loss\n"); + priv->err = -EAGAIN; + priv->state = HIX5I2C_STAT_RW_ERR; + goto stop; + } else if (int_status & I2C_ACK_INTR) { + /* ack error */ + dev_dbg(priv->dev, "No ACK from device\n"); + priv->err = -ENXIO; + priv->state = HIX5I2C_STAT_RW_ERR; + goto stop; + } + + if (int_status & I2C_OVER_INTR) { + if (priv->msg_len > 0) { + ret = hix5hd2_rw_preprocess(priv); + if (ret) { + priv->err = ret; + priv->state = HIX5I2C_STAT_RW_ERR; + goto stop; + } + if (priv->msg->flags & I2C_M_RD) + hix5hd2_read_handle(priv); + else + hix5hd2_write_handle(priv); + } else { + hix5hd2_rw_over(priv); + } + } + +stop: + if ((priv->state == HIX5I2C_STAT_RW_SUCCESS && + priv->msg->len == priv->msg_idx) || + (priv->state == HIX5I2C_STAT_RW_ERR)) { + hix5hd2_i2c_disable_irq(priv); + hix5hd2_i2c_clr_pend_irq(priv); + complete(&priv->msg_complete); + } + + spin_unlock(&priv->lock); + + return IRQ_HANDLED; +} + +static void hix5hd2_i2c_message_start(struct hix5hd2_i2c_priv *priv, int stop) +{ + unsigned long flags; + + spin_lock_irqsave(&priv->lock, flags); + hix5hd2_i2c_clr_all_irq(priv); + hix5hd2_i2c_enable_irq(priv); + + writel_relaxed(i2c_8bit_addr_from_msg(priv->msg), + priv->regs + HIX5I2C_TXR); + + writel_relaxed(I2C_WRITE | I2C_START, priv->regs + HIX5I2C_COM); + spin_unlock_irqrestore(&priv->lock, flags); +} + +static int hix5hd2_i2c_xfer_msg(struct hix5hd2_i2c_priv *priv, + struct i2c_msg *msgs, int stop) +{ + unsigned long timeout; + int ret; + + priv->msg = msgs; + priv->msg_idx = 0; + priv->msg_len = priv->msg->len; + priv->stop = stop; + priv->err = 0; + priv->state = HIX5I2C_STAT_INIT; + + reinit_completion(&priv->msg_complete); + hix5hd2_i2c_message_start(priv, stop); + + timeout = wait_for_completion_timeout(&priv->msg_complete, + priv->adap.timeout); + if (timeout == 0) { + priv->state = HIX5I2C_STAT_RW_ERR; + priv->err = -ETIMEDOUT; + dev_warn(priv->dev, "%s timeout=%d\n", + msgs->flags & I2C_M_RD ? "rx" : "tx", + priv->adap.timeout); + } + ret = priv->state; + + /* + * If this is the last message to be transfered (stop == 1) + * Then check if the bus can be brought back to idle. + */ + if (priv->state == HIX5I2C_STAT_RW_SUCCESS && stop) + ret = hix5hd2_i2c_wait_bus_idle(priv); + + if (ret < 0) + hix5hd2_i2c_reset(priv); + + return priv->err; +} + +static int hix5hd2_i2c_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct hix5hd2_i2c_priv *priv = i2c_get_adapdata(adap); + int i, ret, stop; + + pm_runtime_get_sync(priv->dev); + + for (i = 0; i < num; i++, msgs++) { + if ((i == num - 1) || (msgs->flags & I2C_M_STOP)) + stop = 1; + else + stop = 0; + + ret = hix5hd2_i2c_xfer_msg(priv, msgs, stop); + if (ret < 0) + goto out; + } + + ret = num; + +out: + pm_runtime_mark_last_busy(priv->dev); + pm_runtime_put_autosuspend(priv->dev); + return ret; +} + +static u32 hix5hd2_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); +} + +static const struct i2c_algorithm hix5hd2_i2c_algorithm = { + .master_xfer = hix5hd2_i2c_xfer, + .functionality = hix5hd2_i2c_func, +}; + +static int hix5hd2_i2c_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct hix5hd2_i2c_priv *priv; + unsigned int freq; + int irq, ret; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + if (of_property_read_u32(np, "clock-frequency", &freq)) { + /* use 100k as default value */ + priv->freq = I2C_MAX_STANDARD_MODE_FREQ; + } else { + if (freq > I2C_MAX_FAST_MODE_FREQ) { + priv->freq = I2C_MAX_FAST_MODE_FREQ; + dev_warn(priv->dev, "use max freq %d instead\n", + I2C_MAX_FAST_MODE_FREQ); + } else { + priv->freq = freq; + } + } + + priv->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->regs)) + return PTR_ERR(priv->regs); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + priv->clk = devm_clk_get_enabled(&pdev->dev, NULL); + if (IS_ERR(priv->clk)) { + dev_err(&pdev->dev, "cannot enable clock\n"); + return PTR_ERR(priv->clk); + } + + strscpy(priv->adap.name, "hix5hd2-i2c", sizeof(priv->adap.name)); + priv->dev = &pdev->dev; + priv->adap.owner = THIS_MODULE; + priv->adap.algo = &hix5hd2_i2c_algorithm; + priv->adap.retries = 3; + priv->adap.dev.of_node = np; + priv->adap.algo_data = priv; + priv->adap.dev.parent = &pdev->dev; + i2c_set_adapdata(&priv->adap, priv); + platform_set_drvdata(pdev, priv); + spin_lock_init(&priv->lock); + init_completion(&priv->msg_complete); + + hix5hd2_i2c_init(priv); + + ret = devm_request_irq(&pdev->dev, irq, hix5hd2_i2c_irq, + IRQF_NO_SUSPEND, dev_name(&pdev->dev), priv); + if (ret != 0) { + dev_err(&pdev->dev, "cannot request HS-I2C IRQ %d\n", irq); + return ret; + } + + pm_runtime_set_autosuspend_delay(priv->dev, MSEC_PER_SEC); + pm_runtime_use_autosuspend(priv->dev); + pm_runtime_set_active(priv->dev); + pm_runtime_enable(priv->dev); + + ret = i2c_add_adapter(&priv->adap); + if (ret < 0) + goto err_runtime; + + return ret; + +err_runtime: + pm_runtime_disable(priv->dev); + pm_runtime_set_suspended(priv->dev); + + return ret; +} + +static void hix5hd2_i2c_remove(struct platform_device *pdev) +{ + struct hix5hd2_i2c_priv *priv = platform_get_drvdata(pdev); + + i2c_del_adapter(&priv->adap); + pm_runtime_disable(priv->dev); + pm_runtime_set_suspended(priv->dev); +} + +static int hix5hd2_i2c_runtime_suspend(struct device *dev) +{ + struct hix5hd2_i2c_priv *priv = dev_get_drvdata(dev); + + clk_disable_unprepare(priv->clk); + + return 0; +} + +static int hix5hd2_i2c_runtime_resume(struct device *dev) +{ + struct hix5hd2_i2c_priv *priv = dev_get_drvdata(dev); + + clk_prepare_enable(priv->clk); + hix5hd2_i2c_init(priv); + + return 0; +} + +static const struct dev_pm_ops hix5hd2_i2c_pm_ops = { + RUNTIME_PM_OPS(hix5hd2_i2c_runtime_suspend, + hix5hd2_i2c_runtime_resume, + NULL) +}; + +static const struct of_device_id hix5hd2_i2c_match[] = { + { .compatible = "hisilicon,hix5hd2-i2c" }, + {}, +}; +MODULE_DEVICE_TABLE(of, hix5hd2_i2c_match); + +static struct platform_driver hix5hd2_i2c_driver = { + .probe = hix5hd2_i2c_probe, + .remove_new = hix5hd2_i2c_remove, + .driver = { + .name = "hix5hd2-i2c", + .pm = pm_ptr(&hix5hd2_i2c_pm_ops), + .of_match_table = hix5hd2_i2c_match, + }, +}; + +module_platform_driver(hix5hd2_i2c_driver); + +MODULE_DESCRIPTION("Hix5hd2 I2C Bus driver"); +MODULE_AUTHOR("Wei Yan <sledge.yanwei@huawei.com>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:hix5hd2-i2c"); diff --git a/drivers/i2c/busses/i2c-hydra.c b/drivers/i2c/busses/i2c-hydra.c new file mode 100644 index 000000000..c60b73e93 --- /dev/null +++ b/drivers/i2c/busses/i2c-hydra.c @@ -0,0 +1,150 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + i2c Support for the Apple `Hydra' Mac I/O + + Copyright (c) 1999-2004 Geert Uytterhoeven <geert@linux-m68k.org> + + Based on i2c Support for Via Technologies 82C586B South Bridge + Copyright (c) 1998, 1999 Kyösti Mälkki <kmalkki@cc.hut.fi> + +*/ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/types.h> +#include <linux/i2c.h> +#include <linux/i2c-algo-bit.h> +#include <linux/io.h> +#include <asm/hydra.h> + + +#define HYDRA_CPD_PD0 0x00000001 /* CachePD lines */ +#define HYDRA_CPD_PD1 0x00000002 +#define HYDRA_CPD_PD2 0x00000004 +#define HYDRA_CPD_PD3 0x00000008 + +#define HYDRA_SCLK HYDRA_CPD_PD0 +#define HYDRA_SDAT HYDRA_CPD_PD1 +#define HYDRA_SCLK_OE 0x00000010 +#define HYDRA_SDAT_OE 0x00000020 + +static inline void pdregw(void *data, u32 val) +{ + struct Hydra *hydra = (struct Hydra *)data; + writel(val, &hydra->CachePD); +} + +static inline u32 pdregr(void *data) +{ + struct Hydra *hydra = (struct Hydra *)data; + return readl(&hydra->CachePD); +} + +static void hydra_bit_setscl(void *data, int state) +{ + u32 val = pdregr(data); + if (state) + val &= ~HYDRA_SCLK_OE; + else { + val &= ~HYDRA_SCLK; + val |= HYDRA_SCLK_OE; + } + pdregw(data, val); +} + +static void hydra_bit_setsda(void *data, int state) +{ + u32 val = pdregr(data); + if (state) + val &= ~HYDRA_SDAT_OE; + else { + val &= ~HYDRA_SDAT; + val |= HYDRA_SDAT_OE; + } + pdregw(data, val); +} + +static int hydra_bit_getscl(void *data) +{ + return (pdregr(data) & HYDRA_SCLK) != 0; +} + +static int hydra_bit_getsda(void *data) +{ + return (pdregr(data) & HYDRA_SDAT) != 0; +} + +/* ------------------------------------------------------------------------ */ + +static struct i2c_algo_bit_data hydra_bit_data = { + .setsda = hydra_bit_setsda, + .setscl = hydra_bit_setscl, + .getsda = hydra_bit_getsda, + .getscl = hydra_bit_getscl, + .udelay = 5, + .timeout = HZ +}; + +static struct i2c_adapter hydra_adap = { + .owner = THIS_MODULE, + .name = "Hydra i2c", + .algo_data = &hydra_bit_data, +}; + +static const struct pci_device_id hydra_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_HYDRA) }, + { 0, } +}; + +MODULE_DEVICE_TABLE (pci, hydra_ids); + +static int hydra_probe(struct pci_dev *dev, + const struct pci_device_id *id) +{ + unsigned long base = pci_resource_start(dev, 0); + int res; + + if (!request_mem_region(base+offsetof(struct Hydra, CachePD), 4, + hydra_adap.name)) + return -EBUSY; + + hydra_bit_data.data = pci_ioremap_bar(dev, 0); + if (hydra_bit_data.data == NULL) { + release_mem_region(base+offsetof(struct Hydra, CachePD), 4); + return -ENODEV; + } + + pdregw(hydra_bit_data.data, 0); /* clear SCLK_OE and SDAT_OE */ + hydra_adap.dev.parent = &dev->dev; + res = i2c_bit_add_bus(&hydra_adap); + if (res < 0) { + iounmap(hydra_bit_data.data); + release_mem_region(base+offsetof(struct Hydra, CachePD), 4); + return res; + } + return 0; +} + +static void hydra_remove(struct pci_dev *dev) +{ + pdregw(hydra_bit_data.data, 0); /* clear SCLK_OE and SDAT_OE */ + i2c_del_adapter(&hydra_adap); + iounmap(hydra_bit_data.data); + release_mem_region(pci_resource_start(dev, 0)+ + offsetof(struct Hydra, CachePD), 4); +} + + +static struct pci_driver hydra_driver = { + .name = "hydra_smbus", + .id_table = hydra_ids, + .probe = hydra_probe, + .remove = hydra_remove, +}; + +module_pci_driver(hydra_driver); + +MODULE_AUTHOR("Geert Uytterhoeven <geert@linux-m68k.org>"); +MODULE_DESCRIPTION("i2c for Apple Hydra Mac I/O"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c new file mode 100644 index 000000000..a87e3c15e --- /dev/null +++ b/drivers/i2c/busses/i2c-i801.c @@ -0,0 +1,1865 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl>, + Philip Edelbrock <phil@netroedge.com>, and Mark D. Studebaker + <mdsxyz123@yahoo.com> + Copyright (C) 2007 - 2014 Jean Delvare <jdelvare@suse.de> + Copyright (C) 2010 Intel Corporation, + David Woodhouse <dwmw2@infradead.org> + +*/ + +/* + * Supports the following Intel I/O Controller Hubs (ICH): + * + * I/O Block I2C + * region SMBus Block proc. block + * Chip name PCI ID size PEC buffer call read + * --------------------------------------------------------------------------- + * 82801AA (ICH) 0x2413 16 no no no no + * 82801AB (ICH0) 0x2423 16 no no no no + * 82801BA (ICH2) 0x2443 16 no no no no + * 82801CA (ICH3) 0x2483 32 soft no no no + * 82801DB (ICH4) 0x24c3 32 hard yes no no + * 82801E (ICH5) 0x24d3 32 hard yes yes yes + * 6300ESB 0x25a4 32 hard yes yes yes + * 82801F (ICH6) 0x266a 32 hard yes yes yes + * 6310ESB/6320ESB 0x269b 32 hard yes yes yes + * 82801G (ICH7) 0x27da 32 hard yes yes yes + * 82801H (ICH8) 0x283e 32 hard yes yes yes + * 82801I (ICH9) 0x2930 32 hard yes yes yes + * EP80579 (Tolapai) 0x5032 32 hard yes yes yes + * ICH10 0x3a30 32 hard yes yes yes + * ICH10 0x3a60 32 hard yes yes yes + * 5/3400 Series (PCH) 0x3b30 32 hard yes yes yes + * 6 Series (PCH) 0x1c22 32 hard yes yes yes + * Patsburg (PCH) 0x1d22 32 hard yes yes yes + * Patsburg (PCH) IDF 0x1d70 32 hard yes yes yes + * Patsburg (PCH) IDF 0x1d71 32 hard yes yes yes + * Patsburg (PCH) IDF 0x1d72 32 hard yes yes yes + * DH89xxCC (PCH) 0x2330 32 hard yes yes yes + * Panther Point (PCH) 0x1e22 32 hard yes yes yes + * Lynx Point (PCH) 0x8c22 32 hard yes yes yes + * Lynx Point-LP (PCH) 0x9c22 32 hard yes yes yes + * Avoton (SOC) 0x1f3c 32 hard yes yes yes + * Wellsburg (PCH) 0x8d22 32 hard yes yes yes + * Wellsburg (PCH) MS 0x8d7d 32 hard yes yes yes + * Wellsburg (PCH) MS 0x8d7e 32 hard yes yes yes + * Wellsburg (PCH) MS 0x8d7f 32 hard yes yes yes + * Coleto Creek (PCH) 0x23b0 32 hard yes yes yes + * Wildcat Point (PCH) 0x8ca2 32 hard yes yes yes + * Wildcat Point-LP (PCH) 0x9ca2 32 hard yes yes yes + * BayTrail (SOC) 0x0f12 32 hard yes yes yes + * Braswell (SOC) 0x2292 32 hard yes yes yes + * Sunrise Point-H (PCH) 0xa123 32 hard yes yes yes + * Sunrise Point-LP (PCH) 0x9d23 32 hard yes yes yes + * DNV (SOC) 0x19df 32 hard yes yes yes + * Emmitsburg (PCH) 0x1bc9 32 hard yes yes yes + * Broxton (SOC) 0x5ad4 32 hard yes yes yes + * Lewisburg (PCH) 0xa1a3 32 hard yes yes yes + * Lewisburg Supersku (PCH) 0xa223 32 hard yes yes yes + * Kaby Lake PCH-H (PCH) 0xa2a3 32 hard yes yes yes + * Gemini Lake (SOC) 0x31d4 32 hard yes yes yes + * Cannon Lake-H (PCH) 0xa323 32 hard yes yes yes + * Cannon Lake-LP (PCH) 0x9da3 32 hard yes yes yes + * Cedar Fork (PCH) 0x18df 32 hard yes yes yes + * Ice Lake-LP (PCH) 0x34a3 32 hard yes yes yes + * Ice Lake-N (PCH) 0x38a3 32 hard yes yes yes + * Comet Lake (PCH) 0x02a3 32 hard yes yes yes + * Comet Lake-H (PCH) 0x06a3 32 hard yes yes yes + * Elkhart Lake (PCH) 0x4b23 32 hard yes yes yes + * Tiger Lake-LP (PCH) 0xa0a3 32 hard yes yes yes + * Tiger Lake-H (PCH) 0x43a3 32 hard yes yes yes + * Jasper Lake (SOC) 0x4da3 32 hard yes yes yes + * Comet Lake-V (PCH) 0xa3a3 32 hard yes yes yes + * Alder Lake-S (PCH) 0x7aa3 32 hard yes yes yes + * Alder Lake-P (PCH) 0x51a3 32 hard yes yes yes + * Alder Lake-M (PCH) 0x54a3 32 hard yes yes yes + * Raptor Lake-S (PCH) 0x7a23 32 hard yes yes yes + * Meteor Lake-P (SOC) 0x7e22 32 hard yes yes yes + * Meteor Lake SoC-S (SOC) 0xae22 32 hard yes yes yes + * Meteor Lake PCH-S (PCH) 0x7f23 32 hard yes yes yes + * Birch Stream (SOC) 0x5796 32 hard yes yes yes + * + * Features supported by this driver: + * Software PEC no + * Hardware PEC yes + * Block buffer yes + * Block process call transaction yes + * I2C block read transaction yes (doesn't use the block buffer) + * Slave mode no + * SMBus Host Notify yes + * Interrupt processing yes + * + * See the file Documentation/i2c/busses/i2c-i801.rst for details. + */ + +#define DRV_NAME "i801_smbus" + +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/stddef.h> +#include <linux/delay.h> +#include <linux/ioport.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/i2c-smbus.h> +#include <linux/acpi.h> +#include <linux/io.h> +#include <linux/dmi.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/completion.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/platform_data/itco_wdt.h> +#include <linux/platform_data/x86/p2sb.h> +#include <linux/pm_runtime.h> +#include <linux/mutex.h> + +#if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI +#include <linux/gpio/machine.h> +#include <linux/platform_data/i2c-mux-gpio.h> +#endif + +/* I801 SMBus address offsets */ +#define SMBHSTSTS(p) (0 + (p)->smba) +#define SMBHSTCNT(p) (2 + (p)->smba) +#define SMBHSTCMD(p) (3 + (p)->smba) +#define SMBHSTADD(p) (4 + (p)->smba) +#define SMBHSTDAT0(p) (5 + (p)->smba) +#define SMBHSTDAT1(p) (6 + (p)->smba) +#define SMBBLKDAT(p) (7 + (p)->smba) +#define SMBPEC(p) (8 + (p)->smba) /* ICH3 and later */ +#define SMBAUXSTS(p) (12 + (p)->smba) /* ICH4 and later */ +#define SMBAUXCTL(p) (13 + (p)->smba) /* ICH4 and later */ +#define SMBSLVSTS(p) (16 + (p)->smba) /* ICH3 and later */ +#define SMBSLVCMD(p) (17 + (p)->smba) /* ICH3 and later */ +#define SMBNTFDADD(p) (20 + (p)->smba) /* ICH3 and later */ + +/* PCI Address Constants */ +#define SMBBAR 4 +#define SMBHSTCFG 0x040 +#define TCOBASE 0x050 +#define TCOCTL 0x054 + +#define SBREG_SMBCTRL 0xc6000c +#define SBREG_SMBCTRL_DNV 0xcf000c + +/* Host configuration bits for SMBHSTCFG */ +#define SMBHSTCFG_HST_EN BIT(0) +#define SMBHSTCFG_SMB_SMI_EN BIT(1) +#define SMBHSTCFG_I2C_EN BIT(2) +#define SMBHSTCFG_SPD_WD BIT(4) + +/* TCO configuration bits for TCOCTL */ +#define TCOCTL_EN BIT(8) + +/* Auxiliary status register bits, ICH4+ only */ +#define SMBAUXSTS_CRCE BIT(0) +#define SMBAUXSTS_STCO BIT(1) + +/* Auxiliary control register bits, ICH4+ only */ +#define SMBAUXCTL_CRC BIT(0) +#define SMBAUXCTL_E32B BIT(1) + +/* I801 command constants */ +#define I801_QUICK 0x00 +#define I801_BYTE 0x04 +#define I801_BYTE_DATA 0x08 +#define I801_WORD_DATA 0x0C +#define I801_PROC_CALL 0x10 +#define I801_BLOCK_DATA 0x14 +#define I801_I2C_BLOCK_DATA 0x18 /* ICH5 and later */ +#define I801_BLOCK_PROC_CALL 0x1C + +/* I801 Host Control register bits */ +#define SMBHSTCNT_INTREN BIT(0) +#define SMBHSTCNT_KILL BIT(1) +#define SMBHSTCNT_LAST_BYTE BIT(5) +#define SMBHSTCNT_START BIT(6) +#define SMBHSTCNT_PEC_EN BIT(7) /* ICH3 and later */ + +/* I801 Hosts Status register bits */ +#define SMBHSTSTS_BYTE_DONE BIT(7) +#define SMBHSTSTS_INUSE_STS BIT(6) +#define SMBHSTSTS_SMBALERT_STS BIT(5) +#define SMBHSTSTS_FAILED BIT(4) +#define SMBHSTSTS_BUS_ERR BIT(3) +#define SMBHSTSTS_DEV_ERR BIT(2) +#define SMBHSTSTS_INTR BIT(1) +#define SMBHSTSTS_HOST_BUSY BIT(0) + +/* Host Notify Status register bits */ +#define SMBSLVSTS_HST_NTFY_STS BIT(0) + +/* Host Notify Command register bits */ +#define SMBSLVCMD_SMBALERT_DISABLE BIT(2) +#define SMBSLVCMD_HST_NTFY_INTREN BIT(0) + +#define STATUS_ERROR_FLAGS (SMBHSTSTS_FAILED | SMBHSTSTS_BUS_ERR | \ + SMBHSTSTS_DEV_ERR) + +#define STATUS_FLAGS (SMBHSTSTS_BYTE_DONE | SMBHSTSTS_INTR | \ + STATUS_ERROR_FLAGS) + +/* Older devices have their ID defined in <linux/pci_ids.h> */ +#define PCI_DEVICE_ID_INTEL_COMETLAKE_SMBUS 0x02a3 +#define PCI_DEVICE_ID_INTEL_COMETLAKE_H_SMBUS 0x06a3 +#define PCI_DEVICE_ID_INTEL_BAYTRAIL_SMBUS 0x0f12 +#define PCI_DEVICE_ID_INTEL_CDF_SMBUS 0x18df +#define PCI_DEVICE_ID_INTEL_DNV_SMBUS 0x19df +#define PCI_DEVICE_ID_INTEL_EBG_SMBUS 0x1bc9 +#define PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS 0x1c22 +#define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS 0x1d22 +/* Patsburg also has three 'Integrated Device Function' SMBus controllers */ +#define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF0 0x1d70 +#define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF1 0x1d71 +#define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF2 0x1d72 +#define PCI_DEVICE_ID_INTEL_PANTHERPOINT_SMBUS 0x1e22 +#define PCI_DEVICE_ID_INTEL_AVOTON_SMBUS 0x1f3c +#define PCI_DEVICE_ID_INTEL_BRASWELL_SMBUS 0x2292 +#define PCI_DEVICE_ID_INTEL_DH89XXCC_SMBUS 0x2330 +#define PCI_DEVICE_ID_INTEL_COLETOCREEK_SMBUS 0x23b0 +#define PCI_DEVICE_ID_INTEL_GEMINILAKE_SMBUS 0x31d4 +#define PCI_DEVICE_ID_INTEL_ICELAKE_LP_SMBUS 0x34a3 +#define PCI_DEVICE_ID_INTEL_ICELAKE_N_SMBUS 0x38a3 +#define PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS 0x3b30 +#define PCI_DEVICE_ID_INTEL_TIGERLAKE_H_SMBUS 0x43a3 +#define PCI_DEVICE_ID_INTEL_ELKHART_LAKE_SMBUS 0x4b23 +#define PCI_DEVICE_ID_INTEL_JASPER_LAKE_SMBUS 0x4da3 +#define PCI_DEVICE_ID_INTEL_ALDER_LAKE_P_SMBUS 0x51a3 +#define PCI_DEVICE_ID_INTEL_ALDER_LAKE_M_SMBUS 0x54a3 +#define PCI_DEVICE_ID_INTEL_BIRCH_STREAM_SMBUS 0x5796 +#define PCI_DEVICE_ID_INTEL_BROXTON_SMBUS 0x5ad4 +#define PCI_DEVICE_ID_INTEL_RAPTOR_LAKE_S_SMBUS 0x7a23 +#define PCI_DEVICE_ID_INTEL_ALDER_LAKE_S_SMBUS 0x7aa3 +#define PCI_DEVICE_ID_INTEL_METEOR_LAKE_P_SMBUS 0x7e22 +#define PCI_DEVICE_ID_INTEL_METEOR_LAKE_PCH_S_SMBUS 0x7f23 +#define PCI_DEVICE_ID_INTEL_LYNXPOINT_SMBUS 0x8c22 +#define PCI_DEVICE_ID_INTEL_WILDCATPOINT_SMBUS 0x8ca2 +#define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS 0x8d22 +#define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS0 0x8d7d +#define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS1 0x8d7e +#define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS2 0x8d7f +#define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_SMBUS 0x9c22 +#define PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_SMBUS 0x9ca2 +#define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_SMBUS 0x9d23 +#define PCI_DEVICE_ID_INTEL_CANNONLAKE_LP_SMBUS 0x9da3 +#define PCI_DEVICE_ID_INTEL_TIGERLAKE_LP_SMBUS 0xa0a3 +#define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_SMBUS 0xa123 +#define PCI_DEVICE_ID_INTEL_LEWISBURG_SMBUS 0xa1a3 +#define PCI_DEVICE_ID_INTEL_LEWISBURG_SSKU_SMBUS 0xa223 +#define PCI_DEVICE_ID_INTEL_KABYLAKE_PCH_H_SMBUS 0xa2a3 +#define PCI_DEVICE_ID_INTEL_CANNONLAKE_H_SMBUS 0xa323 +#define PCI_DEVICE_ID_INTEL_COMETLAKE_V_SMBUS 0xa3a3 +#define PCI_DEVICE_ID_INTEL_METEOR_LAKE_SOC_S_SMBUS 0xae22 + +struct i801_mux_config { + char *gpio_chip; + unsigned values[3]; + int n_values; + unsigned classes[3]; + unsigned gpios[2]; /* Relative to gpio_chip->base */ + int n_gpios; +}; + +struct i801_priv { + struct i2c_adapter adapter; + unsigned long smba; + unsigned char original_hstcfg; + unsigned char original_hstcnt; + unsigned char original_slvcmd; + struct pci_dev *pci_dev; + unsigned int features; + + /* isr processing */ + struct completion done; + u8 status; + + /* Command state used by isr for byte-by-byte block transactions */ + u8 cmd; + bool is_read; + int count; + int len; + u8 *data; + +#if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI + const struct i801_mux_config *mux_drvdata; + struct platform_device *mux_pdev; + struct gpiod_lookup_table *lookup; +#endif + struct platform_device *tco_pdev; + + /* + * If set to true the host controller registers are reserved for + * ACPI AML use. Protected by acpi_lock. + */ + bool acpi_reserved; + struct mutex acpi_lock; +}; + +#define FEATURE_SMBUS_PEC BIT(0) +#define FEATURE_BLOCK_BUFFER BIT(1) +#define FEATURE_BLOCK_PROC BIT(2) +#define FEATURE_I2C_BLOCK_READ BIT(3) +#define FEATURE_IRQ BIT(4) +#define FEATURE_HOST_NOTIFY BIT(5) +/* Not really a feature, but it's convenient to handle it as such */ +#define FEATURE_IDF BIT(15) +#define FEATURE_TCO_SPT BIT(16) +#define FEATURE_TCO_CNL BIT(17) + +static const char *i801_feature_names[] = { + "SMBus PEC", + "Block buffer", + "Block process call", + "I2C block read", + "Interrupt", + "SMBus Host Notify", +}; + +static unsigned int disable_features; +module_param(disable_features, uint, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(disable_features, "Disable selected driver features:\n" + "\t\t 0x01 disable SMBus PEC\n" + "\t\t 0x02 disable the block buffer\n" + "\t\t 0x08 disable the I2C block read functionality\n" + "\t\t 0x10 don't use interrupts\n" + "\t\t 0x20 disable SMBus Host Notify "); + +/* Make sure the SMBus host is ready to start transmitting. + Return 0 if it is, -EBUSY if it is not. */ +static int i801_check_pre(struct i801_priv *priv) +{ + int status; + + status = inb_p(SMBHSTSTS(priv)); + if (status & SMBHSTSTS_HOST_BUSY) { + pci_err(priv->pci_dev, "SMBus is busy, can't use it!\n"); + return -EBUSY; + } + + status &= STATUS_FLAGS; + if (status) { + pci_dbg(priv->pci_dev, "Clearing status flags (%02x)\n", status); + outb_p(status, SMBHSTSTS(priv)); + } + + /* + * Clear CRC status if needed. + * During normal operation, i801_check_post() takes care + * of it after every operation. We do it here only in case + * the hardware was already in this state when the driver + * started. + */ + if (priv->features & FEATURE_SMBUS_PEC) { + status = inb_p(SMBAUXSTS(priv)) & SMBAUXSTS_CRCE; + if (status) { + pci_dbg(priv->pci_dev, "Clearing aux status flags (%02x)\n", status); + outb_p(status, SMBAUXSTS(priv)); + } + } + + return 0; +} + +static int i801_check_post(struct i801_priv *priv, int status) +{ + int result = 0; + + /* + * If the SMBus is still busy, we give up + */ + if (unlikely(status < 0)) { + dev_err(&priv->pci_dev->dev, "Transaction timeout\n"); + /* try to stop the current command */ + dev_dbg(&priv->pci_dev->dev, "Terminating the current operation\n"); + outb_p(SMBHSTCNT_KILL, SMBHSTCNT(priv)); + usleep_range(1000, 2000); + outb_p(0, SMBHSTCNT(priv)); + + /* Check if it worked */ + status = inb_p(SMBHSTSTS(priv)); + if ((status & SMBHSTSTS_HOST_BUSY) || + !(status & SMBHSTSTS_FAILED)) + dev_err(&priv->pci_dev->dev, + "Failed terminating the transaction\n"); + return -ETIMEDOUT; + } + + if (status & SMBHSTSTS_FAILED) { + result = -EIO; + dev_err(&priv->pci_dev->dev, "Transaction failed\n"); + } + if (status & SMBHSTSTS_DEV_ERR) { + /* + * This may be a PEC error, check and clear it. + * + * AUXSTS is handled differently from HSTSTS. + * For HSTSTS, i801_isr() or i801_wait_intr() + * has already cleared the error bits in hardware, + * and we are passed a copy of the original value + * in "status". + * For AUXSTS, the hardware register is left + * for us to handle here. + * This is asymmetric, slightly iffy, but safe, + * since all this code is serialized and the CRCE + * bit is harmless as long as it's cleared before + * the next operation. + */ + if ((priv->features & FEATURE_SMBUS_PEC) && + (inb_p(SMBAUXSTS(priv)) & SMBAUXSTS_CRCE)) { + outb_p(SMBAUXSTS_CRCE, SMBAUXSTS(priv)); + result = -EBADMSG; + dev_dbg(&priv->pci_dev->dev, "PEC error\n"); + } else { + result = -ENXIO; + dev_dbg(&priv->pci_dev->dev, "No response\n"); + } + } + if (status & SMBHSTSTS_BUS_ERR) { + result = -EAGAIN; + dev_dbg(&priv->pci_dev->dev, "Lost arbitration\n"); + } + + return result; +} + +/* Wait for BUSY being cleared and either INTR or an error flag being set */ +static int i801_wait_intr(struct i801_priv *priv) +{ + unsigned long timeout = jiffies + priv->adapter.timeout; + int status, busy; + + do { + usleep_range(250, 500); + status = inb_p(SMBHSTSTS(priv)); + busy = status & SMBHSTSTS_HOST_BUSY; + status &= STATUS_ERROR_FLAGS | SMBHSTSTS_INTR; + if (!busy && status) + return status & STATUS_ERROR_FLAGS; + } while (time_is_after_eq_jiffies(timeout)); + + return -ETIMEDOUT; +} + +/* Wait for either BYTE_DONE or an error flag being set */ +static int i801_wait_byte_done(struct i801_priv *priv) +{ + unsigned long timeout = jiffies + priv->adapter.timeout; + int status; + + do { + usleep_range(250, 500); + status = inb_p(SMBHSTSTS(priv)); + if (status & (STATUS_ERROR_FLAGS | SMBHSTSTS_BYTE_DONE)) + return status & STATUS_ERROR_FLAGS; + } while (time_is_after_eq_jiffies(timeout)); + + return -ETIMEDOUT; +} + +static int i801_transaction(struct i801_priv *priv, int xact) +{ + unsigned long result; + const struct i2c_adapter *adap = &priv->adapter; + + if (priv->features & FEATURE_IRQ) { + reinit_completion(&priv->done); + outb_p(xact | SMBHSTCNT_INTREN | SMBHSTCNT_START, + SMBHSTCNT(priv)); + result = wait_for_completion_timeout(&priv->done, adap->timeout); + return result ? priv->status : -ETIMEDOUT; + } + + outb_p(xact | SMBHSTCNT_START, SMBHSTCNT(priv)); + + return i801_wait_intr(priv); +} + +static int i801_block_transaction_by_block(struct i801_priv *priv, + union i2c_smbus_data *data, + char read_write, int command) +{ + int i, len, status, xact; + + switch (command) { + case I2C_SMBUS_BLOCK_PROC_CALL: + xact = I801_BLOCK_PROC_CALL; + break; + case I2C_SMBUS_BLOCK_DATA: + xact = I801_BLOCK_DATA; + break; + default: + return -EOPNOTSUPP; + } + + /* Set block buffer mode */ + outb_p(inb_p(SMBAUXCTL(priv)) | SMBAUXCTL_E32B, SMBAUXCTL(priv)); + + inb_p(SMBHSTCNT(priv)); /* reset the data buffer index */ + + if (read_write == I2C_SMBUS_WRITE) { + len = data->block[0]; + outb_p(len, SMBHSTDAT0(priv)); + for (i = 0; i < len; i++) + outb_p(data->block[i+1], SMBBLKDAT(priv)); + } + + status = i801_transaction(priv, xact); + if (status) + goto out; + + if (read_write == I2C_SMBUS_READ || + command == I2C_SMBUS_BLOCK_PROC_CALL) { + len = inb_p(SMBHSTDAT0(priv)); + if (len < 1 || len > I2C_SMBUS_BLOCK_MAX) { + status = -EPROTO; + goto out; + } + + data->block[0] = len; + for (i = 0; i < len; i++) + data->block[i + 1] = inb_p(SMBBLKDAT(priv)); + } +out: + outb_p(inb_p(SMBAUXCTL(priv)) & ~SMBAUXCTL_E32B, SMBAUXCTL(priv)); + return status; +} + +static void i801_isr_byte_done(struct i801_priv *priv) +{ + if (priv->is_read) { + /* For SMBus block reads, length is received with first byte */ + if (((priv->cmd & 0x1c) == I801_BLOCK_DATA) && + (priv->count == 0)) { + priv->len = inb_p(SMBHSTDAT0(priv)); + if (priv->len < 1 || priv->len > I2C_SMBUS_BLOCK_MAX) { + dev_err(&priv->pci_dev->dev, + "Illegal SMBus block read size %d\n", + priv->len); + /* FIXME: Recover */ + priv->len = I2C_SMBUS_BLOCK_MAX; + } + priv->data[-1] = priv->len; + } + + /* Read next byte */ + if (priv->count < priv->len) + priv->data[priv->count++] = inb(SMBBLKDAT(priv)); + else + dev_dbg(&priv->pci_dev->dev, + "Discarding extra byte on block read\n"); + + /* Set LAST_BYTE for last byte of read transaction */ + if (priv->count == priv->len - 1) + outb_p(priv->cmd | SMBHSTCNT_LAST_BYTE, + SMBHSTCNT(priv)); + } else if (priv->count < priv->len - 1) { + /* Write next byte, except for IRQ after last byte */ + outb_p(priv->data[++priv->count], SMBBLKDAT(priv)); + } +} + +static irqreturn_t i801_host_notify_isr(struct i801_priv *priv) +{ + unsigned short addr; + + addr = inb_p(SMBNTFDADD(priv)) >> 1; + + /* + * With the tested platforms, reading SMBNTFDDAT (22 + (p)->smba) + * always returns 0. Our current implementation doesn't provide + * data, so we just ignore it. + */ + i2c_handle_smbus_host_notify(&priv->adapter, addr); + + /* clear Host Notify bit and return */ + outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv)); + return IRQ_HANDLED; +} + +/* + * There are three kinds of interrupts: + * + * 1) i801 signals transaction completion with one of these interrupts: + * INTR - Success + * DEV_ERR - Invalid command, NAK or communication timeout + * BUS_ERR - SMI# transaction collision + * FAILED - transaction was canceled due to a KILL request + * When any of these occur, update ->status and signal completion. + * + * 2) For byte-by-byte (I2C read/write) transactions, one BYTE_DONE interrupt + * occurs for each byte of a byte-by-byte to prepare the next byte. + * + * 3) Host Notify interrupts + */ +static irqreturn_t i801_isr(int irq, void *dev_id) +{ + struct i801_priv *priv = dev_id; + u16 pcists; + u8 status; + + /* Confirm this is our interrupt */ + pci_read_config_word(priv->pci_dev, PCI_STATUS, &pcists); + if (!(pcists & PCI_STATUS_INTERRUPT)) + return IRQ_NONE; + + if (priv->features & FEATURE_HOST_NOTIFY) { + status = inb_p(SMBSLVSTS(priv)); + if (status & SMBSLVSTS_HST_NTFY_STS) + return i801_host_notify_isr(priv); + } + + status = inb_p(SMBHSTSTS(priv)); + if ((status & (SMBHSTSTS_BYTE_DONE | STATUS_ERROR_FLAGS)) == SMBHSTSTS_BYTE_DONE) + i801_isr_byte_done(priv); + + /* + * Clear IRQ sources: SMB_ALERT status is set after signal assertion + * independently of the interrupt generation being blocked or not + * so clear it always when the status is set. + */ + status &= STATUS_FLAGS | SMBHSTSTS_SMBALERT_STS; + outb_p(status, SMBHSTSTS(priv)); + + status &= STATUS_ERROR_FLAGS | SMBHSTSTS_INTR; + if (status) { + priv->status = status & STATUS_ERROR_FLAGS; + complete(&priv->done); + } + + return IRQ_HANDLED; +} + +/* + * For "byte-by-byte" block transactions: + * I2C write uses cmd=I801_BLOCK_DATA, I2C_EN=1 + * I2C read uses cmd=I801_I2C_BLOCK_DATA + */ +static int i801_block_transaction_byte_by_byte(struct i801_priv *priv, + union i2c_smbus_data *data, + char read_write, int command) +{ + int i, len; + int smbcmd; + int status; + unsigned long result; + const struct i2c_adapter *adap = &priv->adapter; + + if (command == I2C_SMBUS_BLOCK_PROC_CALL) + return -EOPNOTSUPP; + + len = data->block[0]; + + if (read_write == I2C_SMBUS_WRITE) { + outb_p(len, SMBHSTDAT0(priv)); + outb_p(data->block[1], SMBBLKDAT(priv)); + } + + if (command == I2C_SMBUS_I2C_BLOCK_DATA && + read_write == I2C_SMBUS_READ) + smbcmd = I801_I2C_BLOCK_DATA; + else + smbcmd = I801_BLOCK_DATA; + + if (priv->features & FEATURE_IRQ) { + priv->is_read = (read_write == I2C_SMBUS_READ); + if (len == 1 && priv->is_read) + smbcmd |= SMBHSTCNT_LAST_BYTE; + priv->cmd = smbcmd | SMBHSTCNT_INTREN; + priv->len = len; + priv->count = 0; + priv->data = &data->block[1]; + + reinit_completion(&priv->done); + outb_p(priv->cmd | SMBHSTCNT_START, SMBHSTCNT(priv)); + result = wait_for_completion_timeout(&priv->done, adap->timeout); + return result ? priv->status : -ETIMEDOUT; + } + + if (len == 1 && read_write == I2C_SMBUS_READ) + smbcmd |= SMBHSTCNT_LAST_BYTE; + outb_p(smbcmd | SMBHSTCNT_START, SMBHSTCNT(priv)); + + for (i = 1; i <= len; i++) { + status = i801_wait_byte_done(priv); + if (status) + return status; + + if (i == 1 && read_write == I2C_SMBUS_READ + && command != I2C_SMBUS_I2C_BLOCK_DATA) { + len = inb_p(SMBHSTDAT0(priv)); + if (len < 1 || len > I2C_SMBUS_BLOCK_MAX) { + dev_err(&priv->pci_dev->dev, + "Illegal SMBus block read size %d\n", + len); + /* Recover */ + while (inb_p(SMBHSTSTS(priv)) & + SMBHSTSTS_HOST_BUSY) + outb_p(SMBHSTSTS_BYTE_DONE, + SMBHSTSTS(priv)); + outb_p(SMBHSTSTS_INTR, SMBHSTSTS(priv)); + return -EPROTO; + } + data->block[0] = len; + } + + if (read_write == I2C_SMBUS_READ) { + data->block[i] = inb_p(SMBBLKDAT(priv)); + if (i == len - 1) + outb_p(smbcmd | SMBHSTCNT_LAST_BYTE, SMBHSTCNT(priv)); + } + + if (read_write == I2C_SMBUS_WRITE && i+1 <= len) + outb_p(data->block[i+1], SMBBLKDAT(priv)); + + /* signals SMBBLKDAT ready */ + outb_p(SMBHSTSTS_BYTE_DONE, SMBHSTSTS(priv)); + } + + return i801_wait_intr(priv); +} + +static void i801_set_hstadd(struct i801_priv *priv, u8 addr, char read_write) +{ + outb_p((addr << 1) | (read_write & 0x01), SMBHSTADD(priv)); +} + +/* Single value transaction function */ +static int i801_simple_transaction(struct i801_priv *priv, union i2c_smbus_data *data, + u8 addr, u8 hstcmd, char read_write, int command) +{ + int xact, ret; + + switch (command) { + case I2C_SMBUS_QUICK: + i801_set_hstadd(priv, addr, read_write); + xact = I801_QUICK; + break; + case I2C_SMBUS_BYTE: + i801_set_hstadd(priv, addr, read_write); + if (read_write == I2C_SMBUS_WRITE) + outb_p(hstcmd, SMBHSTCMD(priv)); + xact = I801_BYTE; + break; + case I2C_SMBUS_BYTE_DATA: + i801_set_hstadd(priv, addr, read_write); + if (read_write == I2C_SMBUS_WRITE) + outb_p(data->byte, SMBHSTDAT0(priv)); + outb_p(hstcmd, SMBHSTCMD(priv)); + xact = I801_BYTE_DATA; + break; + case I2C_SMBUS_WORD_DATA: + i801_set_hstadd(priv, addr, read_write); + if (read_write == I2C_SMBUS_WRITE) { + outb_p(data->word & 0xff, SMBHSTDAT0(priv)); + outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1(priv)); + } + outb_p(hstcmd, SMBHSTCMD(priv)); + xact = I801_WORD_DATA; + break; + case I2C_SMBUS_PROC_CALL: + i801_set_hstadd(priv, addr, I2C_SMBUS_WRITE); + outb_p(data->word & 0xff, SMBHSTDAT0(priv)); + outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1(priv)); + outb_p(hstcmd, SMBHSTCMD(priv)); + read_write = I2C_SMBUS_READ; + xact = I801_PROC_CALL; + break; + default: + pci_err(priv->pci_dev, "Unsupported transaction %d\n", command); + return -EOPNOTSUPP; + } + + ret = i801_transaction(priv, xact); + if (ret || read_write == I2C_SMBUS_WRITE) + return ret; + + switch (command) { + case I2C_SMBUS_BYTE: + case I2C_SMBUS_BYTE_DATA: + data->byte = inb_p(SMBHSTDAT0(priv)); + break; + case I2C_SMBUS_WORD_DATA: + case I2C_SMBUS_PROC_CALL: + data->word = inb_p(SMBHSTDAT0(priv)) + + (inb_p(SMBHSTDAT1(priv)) << 8); + break; + } + + return 0; +} + +/* Block transaction function */ +static int i801_block_transaction(struct i801_priv *priv, union i2c_smbus_data *data, + u8 addr, u8 hstcmd, char read_write, int command) +{ + int result = 0; + unsigned char hostc; + + if (read_write == I2C_SMBUS_READ && command == I2C_SMBUS_BLOCK_DATA) + data->block[0] = I2C_SMBUS_BLOCK_MAX; + else if (data->block[0] < 1 || data->block[0] > I2C_SMBUS_BLOCK_MAX) + return -EPROTO; + + switch (command) { + case I2C_SMBUS_BLOCK_DATA: + i801_set_hstadd(priv, addr, read_write); + outb_p(hstcmd, SMBHSTCMD(priv)); + break; + case I2C_SMBUS_I2C_BLOCK_DATA: + /* + * NB: page 240 of ICH5 datasheet shows that the R/#W + * bit should be cleared here, even when reading. + * However if SPD Write Disable is set (Lynx Point and later), + * the read will fail if we don't set the R/#W bit. + */ + i801_set_hstadd(priv, addr, + priv->original_hstcfg & SMBHSTCFG_SPD_WD ? + read_write : I2C_SMBUS_WRITE); + if (read_write == I2C_SMBUS_READ) { + /* NB: page 240 of ICH5 datasheet also shows + * that DATA1 is the cmd field when reading + */ + outb_p(hstcmd, SMBHSTDAT1(priv)); + } else + outb_p(hstcmd, SMBHSTCMD(priv)); + + if (read_write == I2C_SMBUS_WRITE) { + /* set I2C_EN bit in configuration register */ + pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &hostc); + pci_write_config_byte(priv->pci_dev, SMBHSTCFG, + hostc | SMBHSTCFG_I2C_EN); + } else if (!(priv->features & FEATURE_I2C_BLOCK_READ)) { + dev_err(&priv->pci_dev->dev, + "I2C block read is unsupported!\n"); + return -EOPNOTSUPP; + } + break; + case I2C_SMBUS_BLOCK_PROC_CALL: + /* Needs to be flagged as write transaction */ + i801_set_hstadd(priv, addr, I2C_SMBUS_WRITE); + outb_p(hstcmd, SMBHSTCMD(priv)); + break; + } + + /* Experience has shown that the block buffer can only be used for + SMBus (not I2C) block transactions, even though the datasheet + doesn't mention this limitation. */ + if ((priv->features & FEATURE_BLOCK_BUFFER) && + command != I2C_SMBUS_I2C_BLOCK_DATA) + result = i801_block_transaction_by_block(priv, data, + read_write, + command); + else + result = i801_block_transaction_byte_by_byte(priv, data, + read_write, + command); + + if (command == I2C_SMBUS_I2C_BLOCK_DATA + && read_write == I2C_SMBUS_WRITE) { + /* restore saved configuration register value */ + pci_write_config_byte(priv->pci_dev, SMBHSTCFG, hostc); + } + return result; +} + +/* Return negative errno on error. */ +static s32 i801_access(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, u8 command, + int size, union i2c_smbus_data *data) +{ + int hwpec, ret; + struct i801_priv *priv = i2c_get_adapdata(adap); + + mutex_lock(&priv->acpi_lock); + if (priv->acpi_reserved) { + mutex_unlock(&priv->acpi_lock); + return -EBUSY; + } + + pm_runtime_get_sync(&priv->pci_dev->dev); + + ret = i801_check_pre(priv); + if (ret) + goto out; + + hwpec = (priv->features & FEATURE_SMBUS_PEC) && (flags & I2C_CLIENT_PEC) + && size != I2C_SMBUS_QUICK + && size != I2C_SMBUS_I2C_BLOCK_DATA; + + if (hwpec) /* enable/disable hardware PEC */ + outb_p(inb_p(SMBAUXCTL(priv)) | SMBAUXCTL_CRC, SMBAUXCTL(priv)); + else + outb_p(inb_p(SMBAUXCTL(priv)) & (~SMBAUXCTL_CRC), + SMBAUXCTL(priv)); + + if (size == I2C_SMBUS_BLOCK_DATA || + size == I2C_SMBUS_I2C_BLOCK_DATA || + size == I2C_SMBUS_BLOCK_PROC_CALL) + ret = i801_block_transaction(priv, data, addr, command, read_write, size); + else + ret = i801_simple_transaction(priv, data, addr, command, read_write, size); + + ret = i801_check_post(priv, ret); + + /* Some BIOSes don't like it when PEC is enabled at reboot or resume + * time, so we forcibly disable it after every transaction. + */ + if (hwpec) + outb_p(inb_p(SMBAUXCTL(priv)) & ~SMBAUXCTL_CRC, SMBAUXCTL(priv)); +out: + /* + * Unlock the SMBus device for use by BIOS/ACPI, + * and clear status flags if not done already. + */ + outb_p(SMBHSTSTS_INUSE_STS | STATUS_FLAGS, SMBHSTSTS(priv)); + + pm_runtime_mark_last_busy(&priv->pci_dev->dev); + pm_runtime_put_autosuspend(&priv->pci_dev->dev); + mutex_unlock(&priv->acpi_lock); + return ret; +} + + +static u32 i801_func(struct i2c_adapter *adapter) +{ + struct i801_priv *priv = i2c_get_adapdata(adapter); + + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_PROC_CALL | + I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_WRITE_I2C_BLOCK | + ((priv->features & FEATURE_SMBUS_PEC) ? I2C_FUNC_SMBUS_PEC : 0) | + ((priv->features & FEATURE_BLOCK_PROC) ? + I2C_FUNC_SMBUS_BLOCK_PROC_CALL : 0) | + ((priv->features & FEATURE_I2C_BLOCK_READ) ? + I2C_FUNC_SMBUS_READ_I2C_BLOCK : 0) | + ((priv->features & FEATURE_HOST_NOTIFY) ? + I2C_FUNC_SMBUS_HOST_NOTIFY : 0); +} + +static void i801_enable_host_notify(struct i2c_adapter *adapter) +{ + struct i801_priv *priv = i2c_get_adapdata(adapter); + + if (!(priv->features & FEATURE_HOST_NOTIFY)) + return; + + /* + * Enable host notify interrupt and block the generation of interrupt + * from the SMB_ALERT signal because the driver does not support + * SMBus Alert. + */ + outb_p(SMBSLVCMD_HST_NTFY_INTREN | SMBSLVCMD_SMBALERT_DISABLE | + priv->original_slvcmd, SMBSLVCMD(priv)); + + /* clear Host Notify bit to allow a new notification */ + outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv)); +} + +static void i801_disable_host_notify(struct i801_priv *priv) +{ + if (!(priv->features & FEATURE_HOST_NOTIFY)) + return; + + outb_p(priv->original_slvcmd, SMBSLVCMD(priv)); +} + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = i801_access, + .functionality = i801_func, +}; + +#define FEATURES_ICH5 (FEATURE_BLOCK_PROC | FEATURE_I2C_BLOCK_READ | \ + FEATURE_IRQ | FEATURE_SMBUS_PEC | \ + FEATURE_BLOCK_BUFFER | FEATURE_HOST_NOTIFY) +#define FEATURES_ICH4 (FEATURE_SMBUS_PEC | FEATURE_BLOCK_BUFFER | \ + FEATURE_HOST_NOTIFY) + +static const struct pci_device_id i801_ids[] = { + { PCI_DEVICE_DATA(INTEL, 82801AA_3, 0) }, + { PCI_DEVICE_DATA(INTEL, 82801AB_3, 0) }, + { PCI_DEVICE_DATA(INTEL, 82801BA_2, 0) }, + { PCI_DEVICE_DATA(INTEL, 82801CA_3, FEATURE_HOST_NOTIFY) }, + { PCI_DEVICE_DATA(INTEL, 82801DB_3, FEATURES_ICH4) }, + { PCI_DEVICE_DATA(INTEL, 82801EB_3, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, ESB_4, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, ICH6_16, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, ICH7_17, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, ESB2_17, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, ICH8_5, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, ICH9_6, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, EP80579_1, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, ICH10_4, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, ICH10_5, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, 5_3400_SERIES_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, COUGARPOINT_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, PATSBURG_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, PATSBURG_SMBUS_IDF0, FEATURES_ICH5 | FEATURE_IDF) }, + { PCI_DEVICE_DATA(INTEL, PATSBURG_SMBUS_IDF1, FEATURES_ICH5 | FEATURE_IDF) }, + { PCI_DEVICE_DATA(INTEL, PATSBURG_SMBUS_IDF2, FEATURES_ICH5 | FEATURE_IDF) }, + { PCI_DEVICE_DATA(INTEL, DH89XXCC_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, PANTHERPOINT_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, LYNXPOINT_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, LYNXPOINT_LP_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, AVOTON_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, WELLSBURG_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, WELLSBURG_SMBUS_MS0, FEATURES_ICH5 | FEATURE_IDF) }, + { PCI_DEVICE_DATA(INTEL, WELLSBURG_SMBUS_MS1, FEATURES_ICH5 | FEATURE_IDF) }, + { PCI_DEVICE_DATA(INTEL, WELLSBURG_SMBUS_MS2, FEATURES_ICH5 | FEATURE_IDF) }, + { PCI_DEVICE_DATA(INTEL, COLETOCREEK_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, GEMINILAKE_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, WILDCATPOINT_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, WILDCATPOINT_LP_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, BAYTRAIL_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, BRASWELL_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, SUNRISEPOINT_H_SMBUS, FEATURES_ICH5 | FEATURE_TCO_SPT) }, + { PCI_DEVICE_DATA(INTEL, SUNRISEPOINT_LP_SMBUS, FEATURES_ICH5 | FEATURE_TCO_SPT) }, + { PCI_DEVICE_DATA(INTEL, CDF_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, DNV_SMBUS, FEATURES_ICH5 | FEATURE_TCO_SPT) }, + { PCI_DEVICE_DATA(INTEL, EBG_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, BROXTON_SMBUS, FEATURES_ICH5) }, + { PCI_DEVICE_DATA(INTEL, LEWISBURG_SMBUS, FEATURES_ICH5 | FEATURE_TCO_SPT) }, + { PCI_DEVICE_DATA(INTEL, LEWISBURG_SSKU_SMBUS, FEATURES_ICH5 | FEATURE_TCO_SPT) }, + { PCI_DEVICE_DATA(INTEL, KABYLAKE_PCH_H_SMBUS, FEATURES_ICH5 | FEATURE_TCO_SPT) }, + { PCI_DEVICE_DATA(INTEL, CANNONLAKE_H_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, CANNONLAKE_LP_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, ICELAKE_LP_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, ICELAKE_N_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, COMETLAKE_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, COMETLAKE_H_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, COMETLAKE_V_SMBUS, FEATURES_ICH5 | FEATURE_TCO_SPT) }, + { PCI_DEVICE_DATA(INTEL, ELKHART_LAKE_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, TIGERLAKE_LP_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, TIGERLAKE_H_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, JASPER_LAKE_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, ALDER_LAKE_S_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, ALDER_LAKE_P_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, ALDER_LAKE_M_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, RAPTOR_LAKE_S_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, METEOR_LAKE_P_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, METEOR_LAKE_SOC_S_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, METEOR_LAKE_PCH_S_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { PCI_DEVICE_DATA(INTEL, BIRCH_STREAM_SMBUS, FEATURES_ICH5 | FEATURE_TCO_CNL) }, + { 0, } +}; + +MODULE_DEVICE_TABLE(pci, i801_ids); + +#if defined CONFIG_X86 && defined CONFIG_DMI +static unsigned char apanel_addr; + +/* Scan the system ROM for the signature "FJKEYINF" */ +static __init const void __iomem *bios_signature(const void __iomem *bios) +{ + ssize_t offset; + const unsigned char signature[] = "FJKEYINF"; + + for (offset = 0; offset < 0x10000; offset += 0x10) { + if (check_signature(bios + offset, signature, + sizeof(signature)-1)) + return bios + offset; + } + return NULL; +} + +static void __init input_apanel_init(void) +{ + void __iomem *bios; + const void __iomem *p; + + bios = ioremap(0xF0000, 0x10000); /* Can't fail */ + p = bios_signature(bios); + if (p) { + /* just use the first address */ + apanel_addr = readb(p + 8 + 3) >> 1; + } + iounmap(bios); +} + +struct dmi_onboard_device_info { + const char *name; + u8 type; + unsigned short i2c_addr; + const char *i2c_type; +}; + +static const struct dmi_onboard_device_info dmi_devices[] = { + { "Syleus", DMI_DEV_TYPE_OTHER, 0x73, "fscsyl" }, + { "Hermes", DMI_DEV_TYPE_OTHER, 0x73, "fscher" }, + { "Hades", DMI_DEV_TYPE_OTHER, 0x73, "fschds" }, +}; + +static void dmi_check_onboard_device(u8 type, const char *name, + struct i2c_adapter *adap) +{ + int i; + struct i2c_board_info info; + + for (i = 0; i < ARRAY_SIZE(dmi_devices); i++) { + /* & ~0x80, ignore enabled/disabled bit */ + if ((type & ~0x80) != dmi_devices[i].type) + continue; + if (strcasecmp(name, dmi_devices[i].name)) + continue; + + memset(&info, 0, sizeof(struct i2c_board_info)); + info.addr = dmi_devices[i].i2c_addr; + strscpy(info.type, dmi_devices[i].i2c_type, I2C_NAME_SIZE); + i2c_new_client_device(adap, &info); + break; + } +} + +/* We use our own function to check for onboard devices instead of + dmi_find_device() as some buggy BIOS's have the devices we are interested + in marked as disabled */ +static void dmi_check_onboard_devices(const struct dmi_header *dm, void *adap) +{ + int i, count; + + if (dm->type != 10) + return; + + count = (dm->length - sizeof(struct dmi_header)) / 2; + for (i = 0; i < count; i++) { + const u8 *d = (char *)(dm + 1) + (i * 2); + const char *name = ((char *) dm) + dm->length; + u8 type = d[0]; + u8 s = d[1]; + + if (!s) + continue; + s--; + while (s > 0 && name[0]) { + name += strlen(name) + 1; + s--; + } + if (name[0] == 0) /* Bogus string reference */ + continue; + + dmi_check_onboard_device(type, name, adap); + } +} + +/* NOTE: Keep this list in sync with drivers/platform/x86/dell-smo8800.c */ +static const char *const acpi_smo8800_ids[] = { + "SMO8800", + "SMO8801", + "SMO8810", + "SMO8811", + "SMO8820", + "SMO8821", + "SMO8830", + "SMO8831", +}; + +static acpi_status check_acpi_smo88xx_device(acpi_handle obj_handle, + u32 nesting_level, + void *context, + void **return_value) +{ + struct acpi_device_info *info; + acpi_status status; + char *hid; + int i; + + status = acpi_get_object_info(obj_handle, &info); + if (ACPI_FAILURE(status)) + return AE_OK; + + if (!(info->valid & ACPI_VALID_HID)) + goto smo88xx_not_found; + + hid = info->hardware_id.string; + if (!hid) + goto smo88xx_not_found; + + i = match_string(acpi_smo8800_ids, ARRAY_SIZE(acpi_smo8800_ids), hid); + if (i < 0) + goto smo88xx_not_found; + + kfree(info); + + *return_value = NULL; + return AE_CTRL_TERMINATE; + +smo88xx_not_found: + kfree(info); + return AE_OK; +} + +static bool is_dell_system_with_lis3lv02d(void) +{ + void *err = ERR_PTR(-ENOENT); + + if (!dmi_match(DMI_SYS_VENDOR, "Dell Inc.")) + return false; + + /* + * Check that ACPI device SMO88xx is present and is functioning. + * Function acpi_get_devices() already filters all ACPI devices + * which are not present or are not functioning. + * ACPI device SMO88xx represents our ST microelectronics lis3lv02d + * accelerometer but unfortunately ACPI does not provide any other + * information (like I2C address). + */ + acpi_get_devices(NULL, check_acpi_smo88xx_device, NULL, &err); + + return !IS_ERR(err); +} + +/* + * Accelerometer's I2C address is not specified in DMI nor ACPI, + * so it is needed to define mapping table based on DMI product names. + */ +static const struct { + const char *dmi_product_name; + unsigned short i2c_addr; +} dell_lis3lv02d_devices[] = { + /* + * Dell platform team told us that these Latitude devices have + * ST microelectronics accelerometer at I2C address 0x29. + */ + { "Latitude E5250", 0x29 }, + { "Latitude E5450", 0x29 }, + { "Latitude E5550", 0x29 }, + { "Latitude E6440", 0x29 }, + { "Latitude E6440 ATG", 0x29 }, + { "Latitude E6540", 0x29 }, + /* + * Additional individual entries were added after verification. + */ + { "Latitude 5480", 0x29 }, + { "Vostro V131", 0x1d }, + { "Vostro 5568", 0x29 }, +}; + +static void register_dell_lis3lv02d_i2c_device(struct i801_priv *priv) +{ + struct i2c_board_info info; + const char *dmi_product_name; + int i; + + dmi_product_name = dmi_get_system_info(DMI_PRODUCT_NAME); + for (i = 0; i < ARRAY_SIZE(dell_lis3lv02d_devices); ++i) { + if (strcmp(dmi_product_name, + dell_lis3lv02d_devices[i].dmi_product_name) == 0) + break; + } + + if (i == ARRAY_SIZE(dell_lis3lv02d_devices)) { + dev_warn(&priv->pci_dev->dev, + "Accelerometer lis3lv02d is present on SMBus but its" + " address is unknown, skipping registration\n"); + return; + } + + memset(&info, 0, sizeof(struct i2c_board_info)); + info.addr = dell_lis3lv02d_devices[i].i2c_addr; + strscpy(info.type, "lis3lv02d", I2C_NAME_SIZE); + i2c_new_client_device(&priv->adapter, &info); +} + +/* Register optional slaves */ +static void i801_probe_optional_slaves(struct i801_priv *priv) +{ + /* Only register slaves on main SMBus channel */ + if (priv->features & FEATURE_IDF) + return; + + if (apanel_addr) { + struct i2c_board_info info = { + .addr = apanel_addr, + .type = "fujitsu_apanel", + }; + + i2c_new_client_device(&priv->adapter, &info); + } + + if (dmi_name_in_vendors("FUJITSU")) + dmi_walk(dmi_check_onboard_devices, &priv->adapter); + + if (is_dell_system_with_lis3lv02d()) + register_dell_lis3lv02d_i2c_device(priv); + + /* Instantiate SPD EEPROMs unless the SMBus is multiplexed */ +#if IS_ENABLED(CONFIG_I2C_MUX_GPIO) + if (!priv->mux_drvdata) +#endif + i2c_register_spd(&priv->adapter); +} +#else +static void __init input_apanel_init(void) {} +static void i801_probe_optional_slaves(struct i801_priv *priv) {} +#endif /* CONFIG_X86 && CONFIG_DMI */ + +#if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI +static struct i801_mux_config i801_mux_config_asus_z8_d12 = { + .gpio_chip = "gpio_ich", + .values = { 0x02, 0x03 }, + .n_values = 2, + .classes = { I2C_CLASS_SPD, I2C_CLASS_SPD }, + .gpios = { 52, 53 }, + .n_gpios = 2, +}; + +static struct i801_mux_config i801_mux_config_asus_z8_d18 = { + .gpio_chip = "gpio_ich", + .values = { 0x02, 0x03, 0x01 }, + .n_values = 3, + .classes = { I2C_CLASS_SPD, I2C_CLASS_SPD, I2C_CLASS_SPD }, + .gpios = { 52, 53 }, + .n_gpios = 2, +}; + +static const struct dmi_system_id mux_dmi_table[] = { + { + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), + DMI_MATCH(DMI_BOARD_NAME, "Z8NA-D6(C)"), + }, + .driver_data = &i801_mux_config_asus_z8_d12, + }, + { + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), + DMI_MATCH(DMI_BOARD_NAME, "Z8P(N)E-D12(X)"), + }, + .driver_data = &i801_mux_config_asus_z8_d12, + }, + { + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), + DMI_MATCH(DMI_BOARD_NAME, "Z8NH-D12"), + }, + .driver_data = &i801_mux_config_asus_z8_d12, + }, + { + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), + DMI_MATCH(DMI_BOARD_NAME, "Z8PH-D12/IFB"), + }, + .driver_data = &i801_mux_config_asus_z8_d12, + }, + { + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), + DMI_MATCH(DMI_BOARD_NAME, "Z8NR-D12"), + }, + .driver_data = &i801_mux_config_asus_z8_d12, + }, + { + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), + DMI_MATCH(DMI_BOARD_NAME, "Z8P(N)H-D12"), + }, + .driver_data = &i801_mux_config_asus_z8_d12, + }, + { + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), + DMI_MATCH(DMI_BOARD_NAME, "Z8PG-D18"), + }, + .driver_data = &i801_mux_config_asus_z8_d18, + }, + { + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), + DMI_MATCH(DMI_BOARD_NAME, "Z8PE-D18"), + }, + .driver_data = &i801_mux_config_asus_z8_d18, + }, + { + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), + DMI_MATCH(DMI_BOARD_NAME, "Z8PS-D12"), + }, + .driver_data = &i801_mux_config_asus_z8_d12, + }, + { } +}; + +/* Setup multiplexing if needed */ +static void i801_add_mux(struct i801_priv *priv) +{ + struct device *dev = &priv->adapter.dev; + const struct i801_mux_config *mux_config; + struct i2c_mux_gpio_platform_data gpio_data; + struct gpiod_lookup_table *lookup; + int i; + + if (!priv->mux_drvdata) + return; + mux_config = priv->mux_drvdata; + + /* Prepare the platform data */ + memset(&gpio_data, 0, sizeof(struct i2c_mux_gpio_platform_data)); + gpio_data.parent = priv->adapter.nr; + gpio_data.values = mux_config->values; + gpio_data.n_values = mux_config->n_values; + gpio_data.classes = mux_config->classes; + gpio_data.idle = I2C_MUX_GPIO_NO_IDLE; + + /* Register GPIO descriptor lookup table */ + lookup = devm_kzalloc(dev, + struct_size(lookup, table, mux_config->n_gpios + 1), + GFP_KERNEL); + if (!lookup) + return; + lookup->dev_id = "i2c-mux-gpio"; + for (i = 0; i < mux_config->n_gpios; i++) + lookup->table[i] = GPIO_LOOKUP(mux_config->gpio_chip, + mux_config->gpios[i], "mux", 0); + gpiod_add_lookup_table(lookup); + priv->lookup = lookup; + + /* + * Register the mux device, we use PLATFORM_DEVID_NONE here + * because since we are referring to the GPIO chip by name we are + * anyways in deep trouble if there is more than one of these + * devices, and there should likely only be one platform controller + * hub. + */ + priv->mux_pdev = platform_device_register_data(dev, "i2c-mux-gpio", + PLATFORM_DEVID_NONE, &gpio_data, + sizeof(struct i2c_mux_gpio_platform_data)); + if (IS_ERR(priv->mux_pdev)) { + gpiod_remove_lookup_table(lookup); + dev_err(dev, "Failed to register i2c-mux-gpio device\n"); + } +} + +static void i801_del_mux(struct i801_priv *priv) +{ + platform_device_unregister(priv->mux_pdev); + gpiod_remove_lookup_table(priv->lookup); +} + +static unsigned int i801_get_adapter_class(struct i801_priv *priv) +{ + const struct dmi_system_id *id; + const struct i801_mux_config *mux_config; + unsigned int class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + int i; + + id = dmi_first_match(mux_dmi_table); + if (id) { + /* Remove branch classes from trunk */ + mux_config = id->driver_data; + for (i = 0; i < mux_config->n_values; i++) + class &= ~mux_config->classes[i]; + + /* Remember for later */ + priv->mux_drvdata = mux_config; + } + + return class; +} +#else +static inline void i801_add_mux(struct i801_priv *priv) { } +static inline void i801_del_mux(struct i801_priv *priv) { } + +static inline unsigned int i801_get_adapter_class(struct i801_priv *priv) +{ + return I2C_CLASS_HWMON | I2C_CLASS_SPD; +} +#endif + +static struct platform_device * +i801_add_tco_spt(struct i801_priv *priv, struct pci_dev *pci_dev, + struct resource *tco_res) +{ + static const struct itco_wdt_platform_data pldata = { + .name = "Intel PCH", + .version = 4, + }; + struct resource *res; + int ret; + + /* + * We must access the NO_REBOOT bit over the Primary to Sideband + * (P2SB) bridge. + */ + + res = &tco_res[1]; + ret = p2sb_bar(pci_dev->bus, 0, res); + if (ret) + return ERR_PTR(ret); + + if (pci_dev->device == PCI_DEVICE_ID_INTEL_DNV_SMBUS) + res->start += SBREG_SMBCTRL_DNV; + else + res->start += SBREG_SMBCTRL; + + res->end = res->start + 3; + + return platform_device_register_resndata(&pci_dev->dev, "iTCO_wdt", -1, + tco_res, 2, &pldata, sizeof(pldata)); +} + +static struct platform_device * +i801_add_tco_cnl(struct i801_priv *priv, struct pci_dev *pci_dev, + struct resource *tco_res) +{ + static const struct itco_wdt_platform_data pldata = { + .name = "Intel PCH", + .version = 6, + }; + + return platform_device_register_resndata(&pci_dev->dev, "iTCO_wdt", -1, + tco_res, 1, &pldata, sizeof(pldata)); +} + +static void i801_add_tco(struct i801_priv *priv) +{ + struct pci_dev *pci_dev = priv->pci_dev; + struct resource tco_res[2], *res; + u32 tco_base, tco_ctl; + + /* If we have ACPI based watchdog use that instead */ + if (acpi_has_watchdog()) + return; + + if (!(priv->features & (FEATURE_TCO_SPT | FEATURE_TCO_CNL))) + return; + + pci_read_config_dword(pci_dev, TCOBASE, &tco_base); + pci_read_config_dword(pci_dev, TCOCTL, &tco_ctl); + if (!(tco_ctl & TCOCTL_EN)) + return; + + memset(tco_res, 0, sizeof(tco_res)); + /* + * Always populate the main iTCO IO resource here. The second entry + * for NO_REBOOT MMIO is filled by the SPT specific function. + */ + res = &tco_res[0]; + res->start = tco_base & ~1; + res->end = res->start + 32 - 1; + res->flags = IORESOURCE_IO; + + if (priv->features & FEATURE_TCO_CNL) + priv->tco_pdev = i801_add_tco_cnl(priv, pci_dev, tco_res); + else + priv->tco_pdev = i801_add_tco_spt(priv, pci_dev, tco_res); + + if (IS_ERR(priv->tco_pdev)) + dev_warn(&pci_dev->dev, "failed to create iTCO device\n"); +} + +#ifdef CONFIG_ACPI +static bool i801_acpi_is_smbus_ioport(const struct i801_priv *priv, + acpi_physical_address address) +{ + return address >= priv->smba && + address <= pci_resource_end(priv->pci_dev, SMBBAR); +} + +static acpi_status +i801_acpi_io_handler(u32 function, acpi_physical_address address, u32 bits, + u64 *value, void *handler_context, void *region_context) +{ + struct i801_priv *priv = handler_context; + struct pci_dev *pdev = priv->pci_dev; + acpi_status status; + + /* + * Once BIOS AML code touches the OpRegion we warn and inhibit any + * further access from the driver itself. This device is now owned + * by the system firmware. + */ + mutex_lock(&priv->acpi_lock); + + if (!priv->acpi_reserved && i801_acpi_is_smbus_ioport(priv, address)) { + priv->acpi_reserved = true; + + dev_warn(&pdev->dev, "BIOS is accessing SMBus registers\n"); + dev_warn(&pdev->dev, "Driver SMBus register access inhibited\n"); + + /* + * BIOS is accessing the host controller so prevent it from + * suspending automatically from now on. + */ + pm_runtime_get_sync(&pdev->dev); + } + + if ((function & ACPI_IO_MASK) == ACPI_READ) + status = acpi_os_read_port(address, (u32 *)value, bits); + else + status = acpi_os_write_port(address, (u32)*value, bits); + + mutex_unlock(&priv->acpi_lock); + + return status; +} + +static int i801_acpi_probe(struct i801_priv *priv) +{ + acpi_handle ah = ACPI_HANDLE(&priv->pci_dev->dev); + acpi_status status; + + status = acpi_install_address_space_handler(ah, ACPI_ADR_SPACE_SYSTEM_IO, + i801_acpi_io_handler, NULL, priv); + if (ACPI_SUCCESS(status)) + return 0; + + return acpi_check_resource_conflict(&priv->pci_dev->resource[SMBBAR]); +} + +static void i801_acpi_remove(struct i801_priv *priv) +{ + acpi_handle ah = ACPI_HANDLE(&priv->pci_dev->dev); + + acpi_remove_address_space_handler(ah, ACPI_ADR_SPACE_SYSTEM_IO, i801_acpi_io_handler); +} +#else +static inline int i801_acpi_probe(struct i801_priv *priv) { return 0; } +static inline void i801_acpi_remove(struct i801_priv *priv) { } +#endif + +static void i801_setup_hstcfg(struct i801_priv *priv) +{ + unsigned char hstcfg = priv->original_hstcfg; + + hstcfg &= ~SMBHSTCFG_I2C_EN; /* SMBus timing */ + hstcfg |= SMBHSTCFG_HST_EN; + pci_write_config_byte(priv->pci_dev, SMBHSTCFG, hstcfg); +} + +static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + int err, i; + struct i801_priv *priv; + + priv = devm_kzalloc(&dev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + i2c_set_adapdata(&priv->adapter, priv); + priv->adapter.owner = THIS_MODULE; + priv->adapter.class = i801_get_adapter_class(priv); + priv->adapter.algo = &smbus_algorithm; + priv->adapter.dev.parent = &dev->dev; + ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&dev->dev)); + priv->adapter.retries = 3; + mutex_init(&priv->acpi_lock); + + priv->pci_dev = dev; + priv->features = id->driver_data; + + /* Disable features on user request */ + for (i = 0; i < ARRAY_SIZE(i801_feature_names); i++) { + if (priv->features & disable_features & (1 << i)) + dev_notice(&dev->dev, "%s disabled by user\n", + i801_feature_names[i]); + } + priv->features &= ~disable_features; + + /* The block process call uses block buffer mode */ + if (!(priv->features & FEATURE_BLOCK_BUFFER)) + priv->features &= ~FEATURE_BLOCK_PROC; + + err = pcim_enable_device(dev); + if (err) { + dev_err(&dev->dev, "Failed to enable SMBus PCI device (%d)\n", + err); + return err; + } + pcim_pin_device(dev); + + /* Determine the address of the SMBus area */ + priv->smba = pci_resource_start(dev, SMBBAR); + if (!priv->smba) { + dev_err(&dev->dev, + "SMBus base address uninitialized, upgrade BIOS\n"); + return -ENODEV; + } + + if (i801_acpi_probe(priv)) + return -ENODEV; + + err = pcim_iomap_regions(dev, 1 << SMBBAR, DRV_NAME); + if (err) { + dev_err(&dev->dev, + "Failed to request SMBus region 0x%lx-0x%Lx\n", + priv->smba, + (unsigned long long)pci_resource_end(dev, SMBBAR)); + i801_acpi_remove(priv); + return err; + } + + pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &priv->original_hstcfg); + i801_setup_hstcfg(priv); + if (!(priv->original_hstcfg & SMBHSTCFG_HST_EN)) + dev_info(&dev->dev, "Enabling SMBus device\n"); + + if (priv->original_hstcfg & SMBHSTCFG_SMB_SMI_EN) { + dev_dbg(&dev->dev, "SMBus using interrupt SMI#\n"); + /* Disable SMBus interrupt feature if SMBus using SMI# */ + priv->features &= ~FEATURE_IRQ; + } + if (priv->original_hstcfg & SMBHSTCFG_SPD_WD) + dev_info(&dev->dev, "SPD Write Disable is set\n"); + + /* Clear special mode bits */ + if (priv->features & (FEATURE_SMBUS_PEC | FEATURE_BLOCK_BUFFER)) + outb_p(inb_p(SMBAUXCTL(priv)) & + ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B), SMBAUXCTL(priv)); + + /* Default timeout in interrupt mode: 200 ms */ + priv->adapter.timeout = HZ / 5; + + if (dev->irq == IRQ_NOTCONNECTED) + priv->features &= ~FEATURE_IRQ; + + if (priv->features & FEATURE_IRQ) { + u16 pcists; + + /* Complain if an interrupt is already pending */ + pci_read_config_word(priv->pci_dev, PCI_STATUS, &pcists); + if (pcists & PCI_STATUS_INTERRUPT) + dev_warn(&dev->dev, "An interrupt is pending!\n"); + } + + if (priv->features & FEATURE_IRQ) { + init_completion(&priv->done); + + err = devm_request_irq(&dev->dev, dev->irq, i801_isr, + IRQF_SHARED, DRV_NAME, priv); + if (err) { + dev_err(&dev->dev, "Failed to allocate irq %d: %d\n", + dev->irq, err); + priv->features &= ~FEATURE_IRQ; + } + } + dev_info(&dev->dev, "SMBus using %s\n", + priv->features & FEATURE_IRQ ? "PCI interrupt" : "polling"); + + /* Host notification uses an interrupt */ + if (!(priv->features & FEATURE_IRQ)) + priv->features &= ~FEATURE_HOST_NOTIFY; + + /* Remember original Interrupt and Host Notify settings */ + priv->original_hstcnt = inb_p(SMBHSTCNT(priv)) & ~SMBHSTCNT_KILL; + if (priv->features & FEATURE_HOST_NOTIFY) + priv->original_slvcmd = inb_p(SMBSLVCMD(priv)); + + i801_add_tco(priv); + + snprintf(priv->adapter.name, sizeof(priv->adapter.name), + "SMBus I801 adapter at %04lx", priv->smba); + err = i2c_add_adapter(&priv->adapter); + if (err) { + platform_device_unregister(priv->tco_pdev); + i801_acpi_remove(priv); + return err; + } + + i801_enable_host_notify(&priv->adapter); + + i801_probe_optional_slaves(priv); + /* We ignore errors - multiplexing is optional */ + i801_add_mux(priv); + + pci_set_drvdata(dev, priv); + + dev_pm_set_driver_flags(&dev->dev, DPM_FLAG_NO_DIRECT_COMPLETE); + pm_runtime_set_autosuspend_delay(&dev->dev, 1000); + pm_runtime_use_autosuspend(&dev->dev); + pm_runtime_put_autosuspend(&dev->dev); + pm_runtime_allow(&dev->dev); + + return 0; +} + +static void i801_remove(struct pci_dev *dev) +{ + struct i801_priv *priv = pci_get_drvdata(dev); + + outb_p(priv->original_hstcnt, SMBHSTCNT(priv)); + i801_disable_host_notify(priv); + i801_del_mux(priv); + i2c_del_adapter(&priv->adapter); + i801_acpi_remove(priv); + pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg); + + platform_device_unregister(priv->tco_pdev); + + /* if acpi_reserved is set then usage_count is incremented already */ + if (!priv->acpi_reserved) + pm_runtime_get_noresume(&dev->dev); + + /* + * do not call pci_disable_device(dev) since it can cause hard hangs on + * some systems during power-off (eg. Fujitsu-Siemens Lifebook E8010) + */ +} + +static void i801_shutdown(struct pci_dev *dev) +{ + struct i801_priv *priv = pci_get_drvdata(dev); + + /* Restore config registers to avoid hard hang on some systems */ + outb_p(priv->original_hstcnt, SMBHSTCNT(priv)); + i801_disable_host_notify(priv); + pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg); +} + +static int i801_suspend(struct device *dev) +{ + struct i801_priv *priv = dev_get_drvdata(dev); + + outb_p(priv->original_hstcnt, SMBHSTCNT(priv)); + pci_write_config_byte(priv->pci_dev, SMBHSTCFG, priv->original_hstcfg); + return 0; +} + +static int i801_resume(struct device *dev) +{ + struct i801_priv *priv = dev_get_drvdata(dev); + + i801_setup_hstcfg(priv); + i801_enable_host_notify(&priv->adapter); + + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(i801_pm_ops, i801_suspend, i801_resume); + +static struct pci_driver i801_driver = { + .name = DRV_NAME, + .id_table = i801_ids, + .probe = i801_probe, + .remove = i801_remove, + .shutdown = i801_shutdown, + .driver = { + .pm = pm_sleep_ptr(&i801_pm_ops), + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + }, +}; + +static int __init i2c_i801_init(void) +{ + if (dmi_name_in_vendors("FUJITSU")) + input_apanel_init(); + return pci_register_driver(&i801_driver); +} + +static void __exit i2c_i801_exit(void) +{ + pci_unregister_driver(&i801_driver); +} + +MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>"); +MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>"); +MODULE_DESCRIPTION("I801 SMBus driver"); +MODULE_LICENSE("GPL"); + +module_init(i2c_i801_init); +module_exit(i2c_i801_exit); diff --git a/drivers/i2c/busses/i2c-ibm_iic.c b/drivers/i2c/busses/i2c-ibm_iic.c new file mode 100644 index 000000000..408820319 --- /dev/null +++ b/drivers/i2c/busses/i2c-ibm_iic.c @@ -0,0 +1,801 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * drivers/i2c/busses/i2c-ibm_iic.c + * + * Support for the IIC peripheral on IBM PPC 4xx + * + * Copyright (c) 2003, 2004 Zultys Technologies. + * Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net> + * + * Copyright (c) 2008 PIKA Technologies + * Sean MacLennan <smaclennan@pikatech.com> + * + * Based on original work by + * Ian DaSilva <idasilva@mvista.com> + * Armin Kuster <akuster@mvista.com> + * Matt Porter <mporter@mvista.com> + * + * Copyright 2000-2003 MontaVista Software Inc. + * + * Original driver version was highly leveraged from i2c-elektor.c + * + * Copyright 1995-97 Simon G. Vogl + * 1998-99 Hans Berglund + * + * With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> + * and even Frodo Looijaard <frodol@dds.nl> + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/ioport.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/sched/signal.h> + +#include <asm/irq.h> +#include <linux/io.h> +#include <linux/i2c.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> + +#include "i2c-ibm_iic.h" + +#define DRIVER_VERSION "2.2" + +MODULE_DESCRIPTION("IBM IIC driver v" DRIVER_VERSION); +MODULE_LICENSE("GPL"); + +static bool iic_force_poll; +module_param(iic_force_poll, bool, 0); +MODULE_PARM_DESC(iic_force_poll, "Force polling mode"); + +static bool iic_force_fast; +module_param(iic_force_fast, bool, 0); +MODULE_PARM_DESC(iic_force_fast, "Force fast mode (400 kHz)"); + +#define DBG_LEVEL 0 + +#ifdef DBG +#undef DBG +#endif + +#ifdef DBG2 +#undef DBG2 +#endif + +#if DBG_LEVEL > 0 +# define DBG(f,x...) printk(KERN_DEBUG "ibm-iic" f, ##x) +#else +# define DBG(f,x...) ((void)0) +#endif +#if DBG_LEVEL > 1 +# define DBG2(f,x...) DBG(f, ##x) +#else +# define DBG2(f,x...) ((void)0) +#endif +#if DBG_LEVEL > 2 +static void dump_iic_regs(const char* header, struct ibm_iic_private* dev) +{ + volatile struct iic_regs __iomem *iic = dev->vaddr; + printk(KERN_DEBUG "ibm-iic%d: %s\n", dev->idx, header); + printk(KERN_DEBUG + " cntl = 0x%02x, mdcntl = 0x%02x\n" + " sts = 0x%02x, extsts = 0x%02x\n" + " clkdiv = 0x%02x, xfrcnt = 0x%02x\n" + " xtcntlss = 0x%02x, directcntl = 0x%02x\n", + in_8(&iic->cntl), in_8(&iic->mdcntl), in_8(&iic->sts), + in_8(&iic->extsts), in_8(&iic->clkdiv), in_8(&iic->xfrcnt), + in_8(&iic->xtcntlss), in_8(&iic->directcntl)); +} +# define DUMP_REGS(h,dev) dump_iic_regs((h),(dev)) +#else +# define DUMP_REGS(h,dev) ((void)0) +#endif + +/* Bus timings (in ns) for bit-banging */ +static struct ibm_iic_timings { + unsigned int hd_sta; + unsigned int su_sto; + unsigned int low; + unsigned int high; + unsigned int buf; +} timings [] = { +/* Standard mode (100 KHz) */ +{ + .hd_sta = 4000, + .su_sto = 4000, + .low = 4700, + .high = 4000, + .buf = 4700, +}, +/* Fast mode (400 KHz) */ +{ + .hd_sta = 600, + .su_sto = 600, + .low = 1300, + .high = 600, + .buf = 1300, +}}; + +/* Enable/disable interrupt generation */ +static inline void iic_interrupt_mode(struct ibm_iic_private* dev, int enable) +{ + out_8(&dev->vaddr->intmsk, enable ? INTRMSK_EIMTC : 0); +} + +/* + * Initialize IIC interface. + */ +static void iic_dev_init(struct ibm_iic_private* dev) +{ + volatile struct iic_regs __iomem *iic = dev->vaddr; + + DBG("%d: init\n", dev->idx); + + /* Clear master address */ + out_8(&iic->lmadr, 0); + out_8(&iic->hmadr, 0); + + /* Clear slave address */ + out_8(&iic->lsadr, 0); + out_8(&iic->hsadr, 0); + + /* Clear status & extended status */ + out_8(&iic->sts, STS_SCMP | STS_IRQA); + out_8(&iic->extsts, EXTSTS_IRQP | EXTSTS_IRQD | EXTSTS_LA + | EXTSTS_ICT | EXTSTS_XFRA); + + /* Set clock divider */ + out_8(&iic->clkdiv, dev->clckdiv); + + /* Clear transfer count */ + out_8(&iic->xfrcnt, 0); + + /* Clear extended control and status */ + out_8(&iic->xtcntlss, XTCNTLSS_SRC | XTCNTLSS_SRS | XTCNTLSS_SWC + | XTCNTLSS_SWS); + + /* Clear control register */ + out_8(&iic->cntl, 0); + + /* Enable interrupts if possible */ + iic_interrupt_mode(dev, dev->irq >= 0); + + /* Set mode control */ + out_8(&iic->mdcntl, MDCNTL_FMDB | MDCNTL_EINT | MDCNTL_EUBS + | (dev->fast_mode ? MDCNTL_FSM : 0)); + + DUMP_REGS("iic_init", dev); +} + +/* + * Reset IIC interface + */ +static void iic_dev_reset(struct ibm_iic_private* dev) +{ + volatile struct iic_regs __iomem *iic = dev->vaddr; + int i; + u8 dc; + + DBG("%d: soft reset\n", dev->idx); + DUMP_REGS("reset", dev); + + /* Place chip in the reset state */ + out_8(&iic->xtcntlss, XTCNTLSS_SRST); + + /* Check if bus is free */ + dc = in_8(&iic->directcntl); + if (!DIRCTNL_FREE(dc)){ + DBG("%d: trying to regain bus control\n", dev->idx); + + /* Try to set bus free state */ + out_8(&iic->directcntl, DIRCNTL_SDAC | DIRCNTL_SCC); + + /* Wait until we regain bus control */ + for (i = 0; i < 100; ++i){ + dc = in_8(&iic->directcntl); + if (DIRCTNL_FREE(dc)) + break; + + /* Toggle SCL line */ + dc ^= DIRCNTL_SCC; + out_8(&iic->directcntl, dc); + udelay(10); + dc ^= DIRCNTL_SCC; + out_8(&iic->directcntl, dc); + + /* be nice */ + cond_resched(); + } + } + + /* Remove reset */ + out_8(&iic->xtcntlss, 0); + + /* Reinitialize interface */ + iic_dev_init(dev); +} + +/* + * Do 0-length transaction using bit-banging through IIC_DIRECTCNTL register. + */ + +/* Wait for SCL and/or SDA to be high */ +static int iic_dc_wait(volatile struct iic_regs __iomem *iic, u8 mask) +{ + unsigned long x = jiffies + HZ / 28 + 2; + while ((in_8(&iic->directcntl) & mask) != mask){ + if (unlikely(time_after(jiffies, x))) + return -1; + cond_resched(); + } + return 0; +} + +static int iic_smbus_quick(struct ibm_iic_private* dev, const struct i2c_msg* p) +{ + volatile struct iic_regs __iomem *iic = dev->vaddr; + const struct ibm_iic_timings *t = &timings[dev->fast_mode ? 1 : 0]; + u8 mask, v, sda; + int i, res; + + /* Only 7-bit addresses are supported */ + if (unlikely(p->flags & I2C_M_TEN)){ + DBG("%d: smbus_quick - 10 bit addresses are not supported\n", + dev->idx); + return -EINVAL; + } + + DBG("%d: smbus_quick(0x%02x)\n", dev->idx, p->addr); + + /* Reset IIC interface */ + out_8(&iic->xtcntlss, XTCNTLSS_SRST); + + /* Wait for bus to become free */ + out_8(&iic->directcntl, DIRCNTL_SDAC | DIRCNTL_SCC); + if (unlikely(iic_dc_wait(iic, DIRCNTL_MSDA | DIRCNTL_MSC))) + goto err; + ndelay(t->buf); + + /* START */ + out_8(&iic->directcntl, DIRCNTL_SCC); + sda = 0; + ndelay(t->hd_sta); + + /* Send address */ + v = i2c_8bit_addr_from_msg(p); + for (i = 0, mask = 0x80; i < 8; ++i, mask >>= 1){ + out_8(&iic->directcntl, sda); + ndelay(t->low / 2); + sda = (v & mask) ? DIRCNTL_SDAC : 0; + out_8(&iic->directcntl, sda); + ndelay(t->low / 2); + + out_8(&iic->directcntl, DIRCNTL_SCC | sda); + if (unlikely(iic_dc_wait(iic, DIRCNTL_MSC))) + goto err; + ndelay(t->high); + } + + /* ACK */ + out_8(&iic->directcntl, sda); + ndelay(t->low / 2); + out_8(&iic->directcntl, DIRCNTL_SDAC); + ndelay(t->low / 2); + out_8(&iic->directcntl, DIRCNTL_SDAC | DIRCNTL_SCC); + if (unlikely(iic_dc_wait(iic, DIRCNTL_MSC))) + goto err; + res = (in_8(&iic->directcntl) & DIRCNTL_MSDA) ? -EREMOTEIO : 1; + ndelay(t->high); + + /* STOP */ + out_8(&iic->directcntl, 0); + ndelay(t->low); + out_8(&iic->directcntl, DIRCNTL_SCC); + if (unlikely(iic_dc_wait(iic, DIRCNTL_MSC))) + goto err; + ndelay(t->su_sto); + out_8(&iic->directcntl, DIRCNTL_SDAC | DIRCNTL_SCC); + + ndelay(t->buf); + + DBG("%d: smbus_quick -> %s\n", dev->idx, res ? "NACK" : "ACK"); +out: + /* Remove reset */ + out_8(&iic->xtcntlss, 0); + + /* Reinitialize interface */ + iic_dev_init(dev); + + return res; +err: + DBG("%d: smbus_quick - bus is stuck\n", dev->idx); + res = -EREMOTEIO; + goto out; +} + +/* + * IIC interrupt handler + */ +static irqreturn_t iic_handler(int irq, void *dev_id) +{ + struct ibm_iic_private* dev = (struct ibm_iic_private*)dev_id; + volatile struct iic_regs __iomem *iic = dev->vaddr; + + DBG2("%d: irq handler, STS = 0x%02x, EXTSTS = 0x%02x\n", + dev->idx, in_8(&iic->sts), in_8(&iic->extsts)); + + /* Acknowledge IRQ and wakeup iic_wait_for_tc */ + out_8(&iic->sts, STS_IRQA | STS_SCMP); + wake_up_interruptible(&dev->wq); + + return IRQ_HANDLED; +} + +/* + * Get master transfer result and clear errors if any. + * Returns the number of actually transferred bytes or error (<0) + */ +static int iic_xfer_result(struct ibm_iic_private* dev) +{ + volatile struct iic_regs __iomem *iic = dev->vaddr; + + if (unlikely(in_8(&iic->sts) & STS_ERR)){ + DBG("%d: xfer error, EXTSTS = 0x%02x\n", dev->idx, + in_8(&iic->extsts)); + + /* Clear errors and possible pending IRQs */ + out_8(&iic->extsts, EXTSTS_IRQP | EXTSTS_IRQD | + EXTSTS_LA | EXTSTS_ICT | EXTSTS_XFRA); + + /* Flush master data buffer */ + out_8(&iic->mdcntl, in_8(&iic->mdcntl) | MDCNTL_FMDB); + + /* Is bus free? + * If error happened during combined xfer + * IIC interface is usually stuck in some strange + * state, the only way out - soft reset. + */ + if ((in_8(&iic->extsts) & EXTSTS_BCS_MASK) != EXTSTS_BCS_FREE){ + DBG("%d: bus is stuck, resetting\n", dev->idx); + iic_dev_reset(dev); + } + return -EREMOTEIO; + } + else + return in_8(&iic->xfrcnt) & XFRCNT_MTC_MASK; +} + +/* + * Try to abort active transfer. + */ +static void iic_abort_xfer(struct ibm_iic_private* dev) +{ + volatile struct iic_regs __iomem *iic = dev->vaddr; + unsigned long x; + + DBG("%d: iic_abort_xfer\n", dev->idx); + + out_8(&iic->cntl, CNTL_HMT); + + /* + * Wait for the abort command to complete. + * It's not worth to be optimized, just poll (timeout >= 1 tick) + */ + x = jiffies + 2; + while ((in_8(&iic->extsts) & EXTSTS_BCS_MASK) != EXTSTS_BCS_FREE){ + if (time_after(jiffies, x)){ + DBG("%d: abort timeout, resetting...\n", dev->idx); + iic_dev_reset(dev); + return; + } + schedule(); + } + + /* Just to clear errors */ + iic_xfer_result(dev); +} + +/* + * Wait for master transfer to complete. + * It puts current process to sleep until we get interrupt or timeout expires. + * Returns the number of transferred bytes or error (<0) + */ +static int iic_wait_for_tc(struct ibm_iic_private* dev){ + + volatile struct iic_regs __iomem *iic = dev->vaddr; + int ret = 0; + + if (dev->irq >= 0){ + /* Interrupt mode */ + ret = wait_event_interruptible_timeout(dev->wq, + !(in_8(&iic->sts) & STS_PT), dev->adap.timeout); + + if (unlikely(ret < 0)) + DBG("%d: wait interrupted\n", dev->idx); + else if (unlikely(in_8(&iic->sts) & STS_PT)){ + DBG("%d: wait timeout\n", dev->idx); + ret = -ETIMEDOUT; + } + } + else { + /* Polling mode */ + unsigned long x = jiffies + dev->adap.timeout; + + while (in_8(&iic->sts) & STS_PT){ + if (unlikely(time_after(jiffies, x))){ + DBG("%d: poll timeout\n", dev->idx); + ret = -ETIMEDOUT; + break; + } + + if (signal_pending(current)){ + DBG("%d: poll interrupted\n", dev->idx); + ret = -ERESTARTSYS; + break; + } + schedule(); + } + } + + if (unlikely(ret < 0)) + iic_abort_xfer(dev); + else + ret = iic_xfer_result(dev); + + DBG2("%d: iic_wait_for_tc -> %d\n", dev->idx, ret); + + return ret; +} + +/* + * Low level master transfer routine + */ +static int iic_xfer_bytes(struct ibm_iic_private* dev, struct i2c_msg* pm, + int combined_xfer) +{ + volatile struct iic_regs __iomem *iic = dev->vaddr; + char* buf = pm->buf; + int i, j, loops, ret = 0; + int len = pm->len; + + u8 cntl = (in_8(&iic->cntl) & CNTL_AMD) | CNTL_PT; + if (pm->flags & I2C_M_RD) + cntl |= CNTL_RW; + + loops = (len + 3) / 4; + for (i = 0; i < loops; ++i, len -= 4){ + int count = len > 4 ? 4 : len; + u8 cmd = cntl | ((count - 1) << CNTL_TCT_SHIFT); + + if (!(cntl & CNTL_RW)) + for (j = 0; j < count; ++j) + out_8((void __iomem *)&iic->mdbuf, *buf++); + + if (i < loops - 1) + cmd |= CNTL_CHT; + else if (combined_xfer) + cmd |= CNTL_RPST; + + DBG2("%d: xfer_bytes, %d, CNTL = 0x%02x\n", dev->idx, count, cmd); + + /* Start transfer */ + out_8(&iic->cntl, cmd); + + /* Wait for completion */ + ret = iic_wait_for_tc(dev); + + if (unlikely(ret < 0)) + break; + else if (unlikely(ret != count)){ + DBG("%d: xfer_bytes, requested %d, transferred %d\n", + dev->idx, count, ret); + + /* If it's not a last part of xfer, abort it */ + if (combined_xfer || (i < loops - 1)) + iic_abort_xfer(dev); + + ret = -EREMOTEIO; + break; + } + + if (cntl & CNTL_RW) + for (j = 0; j < count; ++j) + *buf++ = in_8((void __iomem *)&iic->mdbuf); + } + + return ret > 0 ? 0 : ret; +} + +/* + * Set target slave address for master transfer + */ +static inline void iic_address(struct ibm_iic_private* dev, struct i2c_msg* msg) +{ + volatile struct iic_regs __iomem *iic = dev->vaddr; + u16 addr = msg->addr; + + DBG2("%d: iic_address, 0x%03x (%d-bit)\n", dev->idx, + addr, msg->flags & I2C_M_TEN ? 10 : 7); + + if (msg->flags & I2C_M_TEN){ + out_8(&iic->cntl, CNTL_AMD); + out_8(&iic->lmadr, addr); + out_8(&iic->hmadr, 0xf0 | ((addr >> 7) & 0x06)); + } + else { + out_8(&iic->cntl, 0); + out_8(&iic->lmadr, addr << 1); + } +} + +static inline int iic_invalid_address(const struct i2c_msg* p) +{ + return (p->addr > 0x3ff) || (!(p->flags & I2C_M_TEN) && (p->addr > 0x7f)); +} + +static inline int iic_address_neq(const struct i2c_msg* p1, + const struct i2c_msg* p2) +{ + return (p1->addr != p2->addr) + || ((p1->flags & I2C_M_TEN) != (p2->flags & I2C_M_TEN)); +} + +/* + * Generic master transfer entrypoint. + * Returns the number of processed messages or error (<0) + */ +static int iic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + struct ibm_iic_private* dev = (struct ibm_iic_private*)(i2c_get_adapdata(adap)); + volatile struct iic_regs __iomem *iic = dev->vaddr; + int i, ret = 0; + + DBG2("%d: iic_xfer, %d msg(s)\n", dev->idx, num); + + /* Check the sanity of the passed messages. + * Uhh, generic i2c layer is more suitable place for such code... + */ + if (unlikely(iic_invalid_address(&msgs[0]))){ + DBG("%d: invalid address 0x%03x (%d-bit)\n", dev->idx, + msgs[0].addr, msgs[0].flags & I2C_M_TEN ? 10 : 7); + return -EINVAL; + } + for (i = 0; i < num; ++i){ + if (unlikely(msgs[i].len <= 0)){ + if (num == 1 && !msgs[0].len){ + /* Special case for I2C_SMBUS_QUICK emulation. + * IBM IIC doesn't support 0-length transactions + * so we have to emulate them using bit-banging. + */ + return iic_smbus_quick(dev, &msgs[0]); + } + DBG("%d: invalid len %d in msg[%d]\n", dev->idx, + msgs[i].len, i); + return -EINVAL; + } + if (unlikely(iic_address_neq(&msgs[0], &msgs[i]))){ + DBG("%d: invalid addr in msg[%d]\n", dev->idx, i); + return -EINVAL; + } + } + + /* Check bus state */ + if (unlikely((in_8(&iic->extsts) & EXTSTS_BCS_MASK) != EXTSTS_BCS_FREE)){ + DBG("%d: iic_xfer, bus is not free\n", dev->idx); + + /* Usually it means something serious has happened. + * We *cannot* have unfinished previous transfer + * so it doesn't make any sense to try to stop it. + * Probably we were not able to recover from the + * previous error. + * The only *reasonable* thing I can think of here + * is soft reset. --ebs + */ + iic_dev_reset(dev); + + if ((in_8(&iic->extsts) & EXTSTS_BCS_MASK) != EXTSTS_BCS_FREE){ + DBG("%d: iic_xfer, bus is still not free\n", dev->idx); + return -EREMOTEIO; + } + } + else { + /* Flush master data buffer (just in case) */ + out_8(&iic->mdcntl, in_8(&iic->mdcntl) | MDCNTL_FMDB); + } + + /* Load slave address */ + iic_address(dev, &msgs[0]); + + /* Do real transfer */ + for (i = 0; i < num && !ret; ++i) + ret = iic_xfer_bytes(dev, &msgs[i], i < num - 1); + + return ret < 0 ? ret : num; +} + +static u32 iic_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR; +} + +static const struct i2c_algorithm iic_algo = { + .master_xfer = iic_xfer, + .functionality = iic_func +}; + +/* + * Calculates IICx_CLCKDIV value for a specific OPB clock frequency + */ +static inline u8 iic_clckdiv(unsigned int opb) +{ + /* Compatibility kludge, should go away after all cards + * are fixed to fill correct value for opbfreq. + * Previous driver version used hardcoded divider value 4, + * it corresponds to OPB frequency from the range (40, 50] MHz + */ + if (!opb){ + printk(KERN_WARNING "ibm-iic: using compatibility value for OPB freq," + " fix your board specific setup\n"); + opb = 50000000; + } + + /* Convert to MHz */ + opb /= 1000000; + + if (opb < 20 || opb > 150){ + printk(KERN_WARNING "ibm-iic: invalid OPB clock frequency %u MHz\n", + opb); + opb = opb < 20 ? 20 : 150; + } + return (u8)((opb + 9) / 10 - 1); +} + +static int iic_request_irq(struct platform_device *ofdev, + struct ibm_iic_private *dev) +{ + struct device_node *np = ofdev->dev.of_node; + int irq; + + if (iic_force_poll) + return 0; + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + dev_err(&ofdev->dev, "irq_of_parse_and_map failed\n"); + return 0; + } + + /* Disable interrupts until we finish initialization, assumes + * level-sensitive IRQ setup... + */ + iic_interrupt_mode(dev, 0); + if (request_irq(irq, iic_handler, 0, "IBM IIC", dev)) { + dev_err(&ofdev->dev, "request_irq %d failed\n", irq); + /* Fallback to the polling mode */ + return 0; + } + + return irq; +} + +/* + * Register single IIC interface + */ +static int iic_probe(struct platform_device *ofdev) +{ + struct device_node *np = ofdev->dev.of_node; + struct ibm_iic_private *dev; + struct i2c_adapter *adap; + const u32 *freq; + int ret; + + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + + platform_set_drvdata(ofdev, dev); + + dev->vaddr = of_iomap(np, 0); + if (dev->vaddr == NULL) { + dev_err(&ofdev->dev, "failed to iomap device\n"); + ret = -ENXIO; + goto error_cleanup; + } + + init_waitqueue_head(&dev->wq); + + dev->irq = iic_request_irq(ofdev, dev); + if (!dev->irq) + dev_warn(&ofdev->dev, "using polling mode\n"); + + /* Board specific settings */ + if (iic_force_fast || of_get_property(np, "fast-mode", NULL)) + dev->fast_mode = 1; + + freq = of_get_property(np, "clock-frequency", NULL); + if (freq == NULL) { + freq = of_get_property(np->parent, "clock-frequency", NULL); + if (freq == NULL) { + dev_err(&ofdev->dev, "Unable to get bus frequency\n"); + ret = -EINVAL; + goto error_cleanup; + } + } + + dev->clckdiv = iic_clckdiv(*freq); + dev_dbg(&ofdev->dev, "clckdiv = %d\n", dev->clckdiv); + + /* Initialize IIC interface */ + iic_dev_init(dev); + + /* Register it with i2c layer */ + adap = &dev->adap; + adap->dev.parent = &ofdev->dev; + adap->dev.of_node = of_node_get(np); + strscpy(adap->name, "IBM IIC", sizeof(adap->name)); + i2c_set_adapdata(adap, dev); + adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + adap->algo = &iic_algo; + adap->timeout = HZ; + + ret = i2c_add_adapter(adap); + if (ret < 0) + goto error_cleanup; + + dev_info(&ofdev->dev, "using %s mode\n", + dev->fast_mode ? "fast (400 kHz)" : "standard (100 kHz)"); + + return 0; + +error_cleanup: + if (dev->irq) { + iic_interrupt_mode(dev, 0); + free_irq(dev->irq, dev); + } + + if (dev->vaddr) + iounmap(dev->vaddr); + + kfree(dev); + return ret; +} + +/* + * Cleanup initialized IIC interface + */ +static void iic_remove(struct platform_device *ofdev) +{ + struct ibm_iic_private *dev = platform_get_drvdata(ofdev); + + i2c_del_adapter(&dev->adap); + + if (dev->irq) { + iic_interrupt_mode(dev, 0); + free_irq(dev->irq, dev); + } + + iounmap(dev->vaddr); + kfree(dev); +} + +static const struct of_device_id ibm_iic_match[] = { + { .compatible = "ibm,iic", }, + {} +}; +MODULE_DEVICE_TABLE(of, ibm_iic_match); + +static struct platform_driver ibm_iic_driver = { + .driver = { + .name = "ibm-iic", + .of_match_table = ibm_iic_match, + }, + .probe = iic_probe, + .remove_new = iic_remove, +}; + +module_platform_driver(ibm_iic_driver); diff --git a/drivers/i2c/busses/i2c-ibm_iic.h b/drivers/i2c/busses/i2c-ibm_iic.h new file mode 100644 index 000000000..f0288889c --- /dev/null +++ b/drivers/i2c/busses/i2c-ibm_iic.h @@ -0,0 +1,118 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * drivers/i2c/busses/i2c-ibm_iic.h + * + * Support for the IIC peripheral on IBM PPC 4xx + * + * Copyright (c) 2003 Zultys Technologies. + * Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net> + * + * Based on original work by + * Ian DaSilva <idasilva@mvista.com> + * Armin Kuster <akuster@mvista.com> + * Matt Porter <mporter@mvista.com> + * + * Copyright 2000-2003 MontaVista Software Inc. + */ +#ifndef __I2C_IBM_IIC_H_ +#define __I2C_IBM_IIC_H_ + +#include <linux/i2c.h> + +struct iic_regs { + u16 mdbuf; + u16 sbbuf; + u8 lmadr; + u8 hmadr; + u8 cntl; + u8 mdcntl; + u8 sts; + u8 extsts; + u8 lsadr; + u8 hsadr; + u8 clkdiv; + u8 intmsk; + u8 xfrcnt; + u8 xtcntlss; + u8 directcntl; +}; + +struct ibm_iic_private { + struct i2c_adapter adap; + volatile struct iic_regs __iomem *vaddr; + wait_queue_head_t wq; + int idx; + int irq; + int fast_mode; + u8 clckdiv; +}; + +/* IICx_CNTL register */ +#define CNTL_HMT 0x80 +#define CNTL_AMD 0x40 +#define CNTL_TCT_MASK 0x30 +#define CNTL_TCT_SHIFT 4 +#define CNTL_RPST 0x08 +#define CNTL_CHT 0x04 +#define CNTL_RW 0x02 +#define CNTL_PT 0x01 + +/* IICx_MDCNTL register */ +#define MDCNTL_FSDB 0x80 +#define MDCNTL_FMDB 0x40 +#define MDCNTL_EGC 0x20 +#define MDCNTL_FSM 0x10 +#define MDCNTL_ESM 0x08 +#define MDCNTL_EINT 0x04 +#define MDCNTL_EUBS 0x02 +#define MDCNTL_HSCL 0x01 + +/* IICx_STS register */ +#define STS_SSS 0x80 +#define STS_SLPR 0x40 +#define STS_MDBS 0x20 +#define STS_MDBF 0x10 +#define STS_SCMP 0x08 +#define STS_ERR 0x04 +#define STS_IRQA 0x02 +#define STS_PT 0x01 + +/* IICx_EXTSTS register */ +#define EXTSTS_IRQP 0x80 +#define EXTSTS_BCS_MASK 0x70 +#define EXTSTS_BCS_FREE 0x40 +#define EXTSTS_IRQD 0x08 +#define EXTSTS_LA 0x04 +#define EXTSTS_ICT 0x02 +#define EXTSTS_XFRA 0x01 + +/* IICx_INTRMSK register */ +#define INTRMSK_EIRC 0x80 +#define INTRMSK_EIRS 0x40 +#define INTRMSK_EIWC 0x20 +#define INTRMSK_EIWS 0x10 +#define INTRMSK_EIHE 0x08 +#define INTRMSK_EIIC 0x04 +#define INTRMSK_EITA 0x02 +#define INTRMSK_EIMTC 0x01 + +/* IICx_XFRCNT register */ +#define XFRCNT_MTC_MASK 0x07 + +/* IICx_XTCNTLSS register */ +#define XTCNTLSS_SRC 0x80 +#define XTCNTLSS_SRS 0x40 +#define XTCNTLSS_SWC 0x20 +#define XTCNTLSS_SWS 0x10 +#define XTCNTLSS_SRST 0x01 + +/* IICx_DIRECTCNTL register */ +#define DIRCNTL_SDAC 0x08 +#define DIRCNTL_SCC 0x04 +#define DIRCNTL_MSDA 0x02 +#define DIRCNTL_MSC 0x01 + +/* Check if we really control the I2C bus and bus is free */ +#define DIRCTNL_FREE(v) (((v) & 0x0f) == 0x0f) + +#endif /* __I2C_IBM_IIC_H_ */ diff --git a/drivers/i2c/busses/i2c-icy.c b/drivers/i2c/busses/i2c-icy.c new file mode 100644 index 000000000..febcb6f01 --- /dev/null +++ b/drivers/i2c/busses/i2c-icy.c @@ -0,0 +1,215 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * I2C driver for stand-alone PCF8584 style adapters on Zorro cards + * + * Original ICY documentation can be found on Aminet: + * https://aminet.net/package/docs/hard/icy + * + * There has been a modern community re-print of this design in 2019: + * https://www.a1k.org/forum/index.php?threads/70106/ + * + * The card is basically a Philips PCF8584 connected straight to the + * beginning of the AutoConfig'd address space (register S1 on base+2), + * with /INT on /INT2 on the Zorro bus. + * + * Copyright (c) 2019 Max Staudt <max@enpas.org> + * + * This started as a fork of i2c-elektor.c and has evolved since. + * Thanks go to its authors for providing a base to grow on. + * + * + * IRQ support is currently not implemented. + * + * As it turns out, i2c-algo-pcf is really written with i2c-elektor's + * edge-triggered ISA interrupts in mind, while the Amiga's Zorro bus has + * level-triggered interrupts. This means that once an interrupt occurs, we + * have to tell the PCF8584 to shut up immediately, or it will keep the + * interrupt line busy and cause an IRQ storm. + + * However, because of the PCF8584's host-side protocol, there is no good + * way to just quieten it without side effects. Rather, we have to perform + * the next read/write operation straight away, which will reset the /INT + * pin. This entails re-designing the core of i2c-algo-pcf in the future. + * For now, we never request an IRQ from the PCF8584, and poll it instead. + */ + +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/ioport.h> +#include <linux/kernel.h> +#include <linux/module.h> + +#include <linux/i2c.h> +#include <linux/i2c-algo-pcf.h> + +#include <asm/amigahw.h> +#include <asm/amigaints.h> +#include <linux/zorro.h> + +#include "../algos/i2c-algo-pcf.h" + +struct icy_i2c { + struct i2c_adapter adapter; + + void __iomem *reg_s0; + void __iomem *reg_s1; + struct i2c_client *ltc2990_client; +}; + +/* + * Functions called by i2c-algo-pcf + */ +static void icy_pcf_setpcf(void *data, int ctl, int val) +{ + struct icy_i2c *i2c = (struct icy_i2c *)data; + + u8 __iomem *address = ctl ? i2c->reg_s1 : i2c->reg_s0; + + z_writeb(val, address); +} + +static int icy_pcf_getpcf(void *data, int ctl) +{ + struct icy_i2c *i2c = (struct icy_i2c *)data; + + u8 __iomem *address = ctl ? i2c->reg_s1 : i2c->reg_s0; + + return z_readb(address); +} + +static int icy_pcf_getown(void *data) +{ + return 0x55; +} + +static int icy_pcf_getclock(void *data) +{ + return 0x1c; +} + +static void icy_pcf_waitforpin(void *data) +{ + usleep_range(50, 150); +} + +/* + * Main i2c-icy part + */ +static unsigned short const icy_ltc2990_addresses[] = { + 0x4c, 0x4d, 0x4e, 0x4f, I2C_CLIENT_END +}; + +/* + * Additional sensors exposed once this property is applied: + * + * in1 will be the voltage of the 5V rail, divided by 2. + * in2 will be the voltage of the 12V rail, divided by 4. + * temp3 will be measured using a PCB loop next the chip. + */ +static const u32 icy_ltc2990_meas_mode[] = {0, 3}; + +static const struct property_entry icy_ltc2990_props[] = { + PROPERTY_ENTRY_U32_ARRAY("lltc,meas-mode", icy_ltc2990_meas_mode), + { } +}; + +static const struct software_node icy_ltc2990_node = { + .properties = icy_ltc2990_props, +}; + +static int icy_probe(struct zorro_dev *z, + const struct zorro_device_id *ent) +{ + struct icy_i2c *i2c; + struct i2c_algo_pcf_data *algo_data; + struct i2c_board_info ltc2990_info = { + .type = "ltc2990", + .swnode = &icy_ltc2990_node, + }; + + i2c = devm_kzalloc(&z->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + algo_data = devm_kzalloc(&z->dev, sizeof(*algo_data), GFP_KERNEL); + if (!algo_data) + return -ENOMEM; + + dev_set_drvdata(&z->dev, i2c); + i2c->adapter.dev.parent = &z->dev; + i2c->adapter.owner = THIS_MODULE; + /* i2c->adapter.algo assigned by i2c_pcf_add_bus() */ + i2c->adapter.algo_data = algo_data; + strscpy(i2c->adapter.name, "ICY I2C Zorro adapter", + sizeof(i2c->adapter.name)); + + if (!devm_request_mem_region(&z->dev, + z->resource.start, + 4, i2c->adapter.name)) + return -ENXIO; + + /* Driver private data */ + i2c->reg_s0 = ZTWO_VADDR(z->resource.start); + i2c->reg_s1 = ZTWO_VADDR(z->resource.start + 2); + + algo_data->data = i2c; + algo_data->setpcf = icy_pcf_setpcf; + algo_data->getpcf = icy_pcf_getpcf; + algo_data->getown = icy_pcf_getown; + algo_data->getclock = icy_pcf_getclock; + algo_data->waitforpin = icy_pcf_waitforpin; + + if (i2c_pcf_add_bus(&i2c->adapter)) { + dev_err(&z->dev, "i2c_pcf_add_bus() failed\n"); + return -ENXIO; + } + + dev_info(&z->dev, "ICY I2C controller at %pa, IRQ not implemented\n", + &z->resource.start); + + /* + * The 2019 a1k.org PCBs have an LTC2990 at 0x4c, so start + * it automatically once ltc2990 is modprobed. + * + * in0 is the voltage of the internal 5V power supply. + * temp1 is the temperature inside the chip. + * + * See property_entry above for in1, in2, temp3. + */ + i2c->ltc2990_client = i2c_new_scanned_device(&i2c->adapter, + <c2990_info, + icy_ltc2990_addresses, + NULL); + return 0; +} + +static void icy_remove(struct zorro_dev *z) +{ + struct icy_i2c *i2c = dev_get_drvdata(&z->dev); + + i2c_unregister_device(i2c->ltc2990_client); + i2c_del_adapter(&i2c->adapter); +} + +static const struct zorro_device_id icy_zorro_tbl[] = { + { ZORRO_ID(VMC, 15, 0), }, + { 0 } +}; + +MODULE_DEVICE_TABLE(zorro, icy_zorro_tbl); + +static struct zorro_driver icy_driver = { + .name = "i2c-icy", + .id_table = icy_zorro_tbl, + .probe = icy_probe, + .remove = icy_remove, +}; + +module_driver(icy_driver, + zorro_register_driver, + zorro_unregister_driver); + +MODULE_AUTHOR("Max Staudt <max@enpas.org>"); +MODULE_DESCRIPTION("I2C bus via PCF8584 on ICY Zorro card"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-img-scb.c b/drivers/i2c/busses/i2c-img-scb.c new file mode 100644 index 000000000..f9d4bfef5 --- /dev/null +++ b/drivers/i2c/busses/i2c-img-scb.c @@ -0,0 +1,1509 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * I2C adapter for the IMG Serial Control Bus (SCB) IP block. + * + * Copyright (C) 2009, 2010, 2012, 2014 Imagination Technologies Ltd. + * + * There are three ways that this I2C controller can be driven: + * + * - Raw control of the SDA and SCK signals. + * + * This corresponds to MODE_RAW, which takes control of the signals + * directly for a certain number of clock cycles (the INT_TIMING + * interrupt can be used for timing). + * + * - Atomic commands. A low level I2C symbol (such as generate + * start/stop/ack/nack bit, generate byte, receive byte, and receive + * ACK) is given to the hardware, with detection of completion by bits + * in the LINESTAT register. + * + * This mode of operation is used by MODE_ATOMIC, which uses an I2C + * state machine in the interrupt handler to compose/react to I2C + * transactions using atomic mode commands, and also by MODE_SEQUENCE, + * which emits a simple fixed sequence of atomic mode commands. + * + * Due to software control, the use of atomic commands usually results + * in suboptimal use of the bus, with gaps between the I2C symbols while + * the driver decides what to do next. + * + * - Automatic mode. A bus address, and whether to read/write is + * specified, and the hardware takes care of the I2C state machine, + * using a FIFO to send/receive bytes of data to an I2C slave. The + * driver just has to keep the FIFO drained or filled in response to the + * appropriate FIFO interrupts. + * + * This corresponds to MODE_AUTOMATIC, which manages the FIFOs and deals + * with control of repeated start bits between I2C messages. + * + * Use of automatic mode and the FIFO can make much more efficient use + * of the bus compared to individual atomic commands, with potentially + * no wasted time between I2C symbols or I2C messages. + * + * In most cases MODE_AUTOMATIC is used, however if any of the messages in + * a transaction are zero byte writes (e.g. used by i2cdetect for probing + * the bus), MODE_ATOMIC must be used since automatic mode is normally + * started by the writing of data into the FIFO. + * + * The other modes are used in specific circumstances where MODE_ATOMIC and + * MODE_AUTOMATIC aren't appropriate. MODE_RAW is used to implement a bus + * recovery routine. MODE_SEQUENCE is used to reset the bus and make sure + * it is in a sane state. + * + * Notice that the driver implements a timer-based timeout mechanism. + * The reason for this mechanism is to reduce the number of interrupts + * received in automatic mode. + * + * The driver would get a slave event and transaction done interrupts for + * each atomic mode command that gets completed. However, these events are + * not needed in automatic mode, becase those atomic mode commands are + * managed automatically by the hardware. + * + * In practice, normal I2C transactions will be complete well before you + * get the timer interrupt, as the timer is re-scheduled during FIFO + * maintenance and disabled after the transaction is complete. + * + * In this way normal automatic mode operation isn't impacted by + * unnecessary interrupts, but the exceptional abort condition can still be + * detected (with a slight delay). + */ + +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/slab.h> +#include <linux/timer.h> + +/* Register offsets */ + +#define SCB_STATUS_REG 0x00 +#define SCB_OVERRIDE_REG 0x04 +#define SCB_READ_ADDR_REG 0x08 +#define SCB_READ_COUNT_REG 0x0c +#define SCB_WRITE_ADDR_REG 0x10 +#define SCB_READ_DATA_REG 0x14 +#define SCB_WRITE_DATA_REG 0x18 +#define SCB_FIFO_STATUS_REG 0x1c +#define SCB_CONTROL_SOFT_RESET 0x1f +#define SCB_CLK_SET_REG 0x3c +#define SCB_INT_STATUS_REG 0x40 +#define SCB_INT_CLEAR_REG 0x44 +#define SCB_INT_MASK_REG 0x48 +#define SCB_CONTROL_REG 0x4c +#define SCB_TIME_TPL_REG 0x50 +#define SCB_TIME_TPH_REG 0x54 +#define SCB_TIME_TP2S_REG 0x58 +#define SCB_TIME_TBI_REG 0x60 +#define SCB_TIME_TSL_REG 0x64 +#define SCB_TIME_TDL_REG 0x68 +#define SCB_TIME_TSDL_REG 0x6c +#define SCB_TIME_TSDH_REG 0x70 +#define SCB_READ_XADDR_REG 0x74 +#define SCB_WRITE_XADDR_REG 0x78 +#define SCB_WRITE_COUNT_REG 0x7c +#define SCB_CORE_REV_REG 0x80 +#define SCB_TIME_TCKH_REG 0x84 +#define SCB_TIME_TCKL_REG 0x88 +#define SCB_FIFO_FLUSH_REG 0x8c +#define SCB_READ_FIFO_REG 0x94 +#define SCB_CLEAR_REG 0x98 + +/* SCB_CONTROL_REG bits */ + +#define SCB_CONTROL_CLK_ENABLE 0x1e0 +#define SCB_CONTROL_TRANSACTION_HALT 0x200 + +#define FIFO_READ_FULL BIT(0) +#define FIFO_READ_EMPTY BIT(1) +#define FIFO_WRITE_FULL BIT(2) +#define FIFO_WRITE_EMPTY BIT(3) + +/* SCB_CLK_SET_REG bits */ +#define SCB_FILT_DISABLE BIT(31) +#define SCB_FILT_BYPASS BIT(30) +#define SCB_FILT_INC_MASK 0x7f +#define SCB_FILT_INC_SHIFT 16 +#define SCB_INC_MASK 0x7f +#define SCB_INC_SHIFT 8 + +/* SCB_INT_*_REG bits */ + +#define INT_BUS_INACTIVE BIT(0) +#define INT_UNEXPECTED_START BIT(1) +#define INT_SCLK_LOW_TIMEOUT BIT(2) +#define INT_SDAT_LOW_TIMEOUT BIT(3) +#define INT_WRITE_ACK_ERR BIT(4) +#define INT_ADDR_ACK_ERR BIT(5) +#define INT_FIFO_FULL BIT(9) +#define INT_FIFO_FILLING BIT(10) +#define INT_FIFO_EMPTY BIT(11) +#define INT_FIFO_EMPTYING BIT(12) +#define INT_TRANSACTION_DONE BIT(15) +#define INT_SLAVE_EVENT BIT(16) +#define INT_MASTER_HALTED BIT(17) +#define INT_TIMING BIT(18) +#define INT_STOP_DETECTED BIT(19) + +#define INT_FIFO_FULL_FILLING (INT_FIFO_FULL | INT_FIFO_FILLING) + +/* Level interrupts need clearing after handling instead of before */ +#define INT_LEVEL 0x01e00 + +/* Don't allow any interrupts while the clock may be off */ +#define INT_ENABLE_MASK_INACTIVE 0x00000 + +/* Interrupt masks for the different driver modes */ + +#define INT_ENABLE_MASK_RAW INT_TIMING + +#define INT_ENABLE_MASK_ATOMIC (INT_TRANSACTION_DONE | \ + INT_SLAVE_EVENT | \ + INT_ADDR_ACK_ERR | \ + INT_WRITE_ACK_ERR) + +#define INT_ENABLE_MASK_AUTOMATIC (INT_SCLK_LOW_TIMEOUT | \ + INT_ADDR_ACK_ERR | \ + INT_WRITE_ACK_ERR | \ + INT_FIFO_FULL | \ + INT_FIFO_FILLING | \ + INT_FIFO_EMPTY | \ + INT_MASTER_HALTED | \ + INT_STOP_DETECTED) + +#define INT_ENABLE_MASK_WAITSTOP (INT_SLAVE_EVENT | \ + INT_ADDR_ACK_ERR | \ + INT_WRITE_ACK_ERR) + +/* SCB_STATUS_REG fields */ + +#define LINESTAT_SCLK_LINE_STATUS BIT(0) +#define LINESTAT_SCLK_EN BIT(1) +#define LINESTAT_SDAT_LINE_STATUS BIT(2) +#define LINESTAT_SDAT_EN BIT(3) +#define LINESTAT_DET_START_STATUS BIT(4) +#define LINESTAT_DET_STOP_STATUS BIT(5) +#define LINESTAT_DET_ACK_STATUS BIT(6) +#define LINESTAT_DET_NACK_STATUS BIT(7) +#define LINESTAT_BUS_IDLE BIT(8) +#define LINESTAT_T_DONE_STATUS BIT(9) +#define LINESTAT_SCLK_OUT_STATUS BIT(10) +#define LINESTAT_SDAT_OUT_STATUS BIT(11) +#define LINESTAT_GEN_LINE_MASK_STATUS BIT(12) +#define LINESTAT_START_BIT_DET BIT(13) +#define LINESTAT_STOP_BIT_DET BIT(14) +#define LINESTAT_ACK_DET BIT(15) +#define LINESTAT_NACK_DET BIT(16) +#define LINESTAT_INPUT_HELD_V BIT(17) +#define LINESTAT_ABORT_DET BIT(18) +#define LINESTAT_ACK_OR_NACK_DET (LINESTAT_ACK_DET | LINESTAT_NACK_DET) +#define LINESTAT_INPUT_DATA 0xff000000 +#define LINESTAT_INPUT_DATA_SHIFT 24 + +#define LINESTAT_CLEAR_SHIFT 13 +#define LINESTAT_LATCHED (0x3f << LINESTAT_CLEAR_SHIFT) + +/* SCB_OVERRIDE_REG fields */ + +#define OVERRIDE_SCLK_OVR BIT(0) +#define OVERRIDE_SCLKEN_OVR BIT(1) +#define OVERRIDE_SDAT_OVR BIT(2) +#define OVERRIDE_SDATEN_OVR BIT(3) +#define OVERRIDE_MASTER BIT(9) +#define OVERRIDE_LINE_OVR_EN BIT(10) +#define OVERRIDE_DIRECT BIT(11) +#define OVERRIDE_CMD_SHIFT 4 +#define OVERRIDE_CMD_MASK 0x1f +#define OVERRIDE_DATA_SHIFT 24 + +#define OVERRIDE_SCLK_DOWN (OVERRIDE_LINE_OVR_EN | \ + OVERRIDE_SCLKEN_OVR) +#define OVERRIDE_SCLK_UP (OVERRIDE_LINE_OVR_EN | \ + OVERRIDE_SCLKEN_OVR | \ + OVERRIDE_SCLK_OVR) +#define OVERRIDE_SDAT_DOWN (OVERRIDE_LINE_OVR_EN | \ + OVERRIDE_SDATEN_OVR) +#define OVERRIDE_SDAT_UP (OVERRIDE_LINE_OVR_EN | \ + OVERRIDE_SDATEN_OVR | \ + OVERRIDE_SDAT_OVR) + +/* OVERRIDE_CMD values */ + +#define CMD_PAUSE 0x00 +#define CMD_GEN_DATA 0x01 +#define CMD_GEN_START 0x02 +#define CMD_GEN_STOP 0x03 +#define CMD_GEN_ACK 0x04 +#define CMD_GEN_NACK 0x05 +#define CMD_RET_DATA 0x08 +#define CMD_RET_ACK 0x09 + +/* Fixed timing values */ + +#define TIMEOUT_TBI 0x0 +#define TIMEOUT_TSL 0xffff +#define TIMEOUT_TDL 0x0 + +/* Transaction timeout */ + +#define IMG_I2C_TIMEOUT (msecs_to_jiffies(1000)) + +/* + * Worst incs are 1 (inaccurate) and 16*256 (irregular). + * So a sensible inc is the logarithmic mean: 64 (2^6), which is + * in the middle of the valid range (0-127). + */ +#define SCB_OPT_INC 64 + +/* Setup the clock enable filtering for 25 ns */ +#define SCB_FILT_GLITCH 25 + +/* + * Bits to return from interrupt handler functions for different modes. + * This delays completion until we've finished with the registers, so that the + * function waiting for completion can safely disable the clock to save power. + */ +#define ISR_COMPLETE_M BIT(31) +#define ISR_FATAL_M BIT(30) +#define ISR_WAITSTOP BIT(29) +#define ISR_STATUS_M 0x0000ffff /* contains +ve errno */ +#define ISR_COMPLETE(err) (ISR_COMPLETE_M | (ISR_STATUS_M & (err))) +#define ISR_FATAL(err) (ISR_COMPLETE(err) | ISR_FATAL_M) + +#define IMG_I2C_PM_TIMEOUT 1000 /* ms */ + +enum img_i2c_mode { + MODE_INACTIVE, + MODE_RAW, + MODE_ATOMIC, + MODE_AUTOMATIC, + MODE_SEQUENCE, + MODE_FATAL, + MODE_WAITSTOP, + MODE_SUSPEND, +}; + +/* Timing parameters for i2c modes (in ns) */ +struct img_i2c_timings { + const char *name; + unsigned int max_bitrate; + unsigned int tckh, tckl, tsdh, tsdl; + unsigned int tp2s, tpl, tph; +}; + +/* The timings array must be ordered from slower to faster */ +static struct img_i2c_timings timings[] = { + /* Standard mode */ + { + .name = "standard", + .max_bitrate = I2C_MAX_STANDARD_MODE_FREQ, + .tckh = 4000, + .tckl = 4700, + .tsdh = 4700, + .tsdl = 8700, + .tp2s = 4700, + .tpl = 4700, + .tph = 4000, + }, + /* Fast mode */ + { + .name = "fast", + .max_bitrate = I2C_MAX_FAST_MODE_FREQ, + .tckh = 600, + .tckl = 1300, + .tsdh = 600, + .tsdl = 1200, + .tp2s = 1300, + .tpl = 600, + .tph = 600, + }, +}; + +/* Reset dance */ +static u8 img_i2c_reset_seq[] = { CMD_GEN_START, + CMD_GEN_DATA, 0xff, + CMD_RET_ACK, + CMD_GEN_START, + CMD_GEN_STOP, + 0 }; +/* Just issue a stop (after an abort condition) */ +static u8 img_i2c_stop_seq[] = { CMD_GEN_STOP, + 0 }; + +/* We're interested in different interrupts depending on the mode */ +static unsigned int img_i2c_int_enable_by_mode[] = { + [MODE_INACTIVE] = INT_ENABLE_MASK_INACTIVE, + [MODE_RAW] = INT_ENABLE_MASK_RAW, + [MODE_ATOMIC] = INT_ENABLE_MASK_ATOMIC, + [MODE_AUTOMATIC] = INT_ENABLE_MASK_AUTOMATIC, + [MODE_SEQUENCE] = INT_ENABLE_MASK_ATOMIC, + [MODE_FATAL] = 0, + [MODE_WAITSTOP] = INT_ENABLE_MASK_WAITSTOP, + [MODE_SUSPEND] = 0, +}; + +/* Atomic command names */ +static const char * const img_i2c_atomic_cmd_names[] = { + [CMD_PAUSE] = "PAUSE", + [CMD_GEN_DATA] = "GEN_DATA", + [CMD_GEN_START] = "GEN_START", + [CMD_GEN_STOP] = "GEN_STOP", + [CMD_GEN_ACK] = "GEN_ACK", + [CMD_GEN_NACK] = "GEN_NACK", + [CMD_RET_DATA] = "RET_DATA", + [CMD_RET_ACK] = "RET_ACK", +}; + +struct img_i2c { + struct i2c_adapter adap; + + void __iomem *base; + + /* + * The scb core clock is used to get the input frequency, and to disable + * it after every set of transactions to save some power. + */ + struct clk *scb_clk, *sys_clk; + unsigned int bitrate; + bool need_wr_rd_fence; + + /* state */ + struct completion msg_complete; + spinlock_t lock; /* lock before doing anything with the state */ + struct i2c_msg msg; + + /* After the last transaction, wait for a stop bit */ + bool last_msg; + int msg_status; + + enum img_i2c_mode mode; + u32 int_enable; /* depends on mode */ + u32 line_status; /* line status over command */ + + /* + * To avoid slave event interrupts in automatic mode, use a timer to + * poll the abort condition if we don't get an interrupt for too long. + */ + struct timer_list check_timer; + bool t_halt; + + /* atomic mode state */ + bool at_t_done; + bool at_slave_event; + int at_cur_cmd; + u8 at_cur_data; + + /* Sequence: either reset or stop. See img_i2c_sequence. */ + u8 *seq; + + /* raw mode */ + unsigned int raw_timeout; +}; + +static int img_i2c_runtime_suspend(struct device *dev); +static int img_i2c_runtime_resume(struct device *dev); + +static void img_i2c_writel(struct img_i2c *i2c, u32 offset, u32 value) +{ + writel(value, i2c->base + offset); +} + +static u32 img_i2c_readl(struct img_i2c *i2c, u32 offset) +{ + return readl(i2c->base + offset); +} + +/* + * The code to read from the master read fifo, and write to the master + * write fifo, checks a bit in an SCB register before every byte to + * ensure that the fifo is not full (write fifo) or empty (read fifo). + * Due to clock domain crossing inside the SCB block the updated value + * of this bit is only visible after 2 cycles. + * + * The scb_wr_rd_fence() function does 2 dummy writes (to the read-only + * revision register), and it's called after reading from or writing to the + * fifos to ensure that subsequent reads of the fifo status bits do not read + * stale values. + */ +static void img_i2c_wr_rd_fence(struct img_i2c *i2c) +{ + if (i2c->need_wr_rd_fence) { + img_i2c_writel(i2c, SCB_CORE_REV_REG, 0); + img_i2c_writel(i2c, SCB_CORE_REV_REG, 0); + } +} + +static void img_i2c_switch_mode(struct img_i2c *i2c, enum img_i2c_mode mode) +{ + i2c->mode = mode; + i2c->int_enable = img_i2c_int_enable_by_mode[mode]; + i2c->line_status = 0; +} + +static void img_i2c_raw_op(struct img_i2c *i2c) +{ + i2c->raw_timeout = 0; + img_i2c_writel(i2c, SCB_OVERRIDE_REG, + OVERRIDE_SCLKEN_OVR | + OVERRIDE_SDATEN_OVR | + OVERRIDE_MASTER | + OVERRIDE_LINE_OVR_EN | + OVERRIDE_DIRECT | + ((i2c->at_cur_cmd & OVERRIDE_CMD_MASK) << OVERRIDE_CMD_SHIFT) | + (i2c->at_cur_data << OVERRIDE_DATA_SHIFT)); +} + +static const char *img_i2c_atomic_op_name(unsigned int cmd) +{ + if (unlikely(cmd >= ARRAY_SIZE(img_i2c_atomic_cmd_names))) + return "UNKNOWN"; + return img_i2c_atomic_cmd_names[cmd]; +} + +/* Send a single atomic mode command to the hardware */ +static void img_i2c_atomic_op(struct img_i2c *i2c, int cmd, u8 data) +{ + i2c->at_cur_cmd = cmd; + i2c->at_cur_data = data; + + /* work around lack of data setup time when generating data */ + if (cmd == CMD_GEN_DATA && i2c->mode == MODE_ATOMIC) { + u32 line_status = img_i2c_readl(i2c, SCB_STATUS_REG); + + if (line_status & LINESTAT_SDAT_LINE_STATUS && !(data & 0x80)) { + /* hold the data line down for a moment */ + img_i2c_switch_mode(i2c, MODE_RAW); + img_i2c_raw_op(i2c); + return; + } + } + + dev_dbg(i2c->adap.dev.parent, + "atomic cmd=%s (%d) data=%#x\n", + img_i2c_atomic_op_name(cmd), cmd, data); + i2c->at_t_done = (cmd == CMD_RET_DATA || cmd == CMD_RET_ACK); + i2c->at_slave_event = false; + i2c->line_status = 0; + + img_i2c_writel(i2c, SCB_OVERRIDE_REG, + ((cmd & OVERRIDE_CMD_MASK) << OVERRIDE_CMD_SHIFT) | + OVERRIDE_MASTER | + OVERRIDE_DIRECT | + (data << OVERRIDE_DATA_SHIFT)); +} + +/* Start a transaction in atomic mode */ +static void img_i2c_atomic_start(struct img_i2c *i2c) +{ + img_i2c_switch_mode(i2c, MODE_ATOMIC); + img_i2c_writel(i2c, SCB_INT_MASK_REG, i2c->int_enable); + img_i2c_atomic_op(i2c, CMD_GEN_START, 0x00); +} + +static void img_i2c_soft_reset(struct img_i2c *i2c) +{ + i2c->t_halt = false; + img_i2c_writel(i2c, SCB_CONTROL_REG, 0); + img_i2c_writel(i2c, SCB_CONTROL_REG, + SCB_CONTROL_CLK_ENABLE | SCB_CONTROL_SOFT_RESET); +} + +/* + * Enable or release transaction halt for control of repeated starts. + * In version 3.3 of the IP when transaction halt is set, an interrupt + * will be generated after each byte of a transfer instead of after + * every transfer but before the stop bit. + * Due to this behaviour we have to be careful that every time we + * release the transaction halt we have to re-enable it straight away + * so that we only process a single byte, not doing so will result in + * all remaining bytes been processed and a stop bit being issued, + * which will prevent us having a repeated start. + */ +static void img_i2c_transaction_halt(struct img_i2c *i2c, bool t_halt) +{ + u32 val; + + if (i2c->t_halt == t_halt) + return; + i2c->t_halt = t_halt; + val = img_i2c_readl(i2c, SCB_CONTROL_REG); + if (t_halt) + val |= SCB_CONTROL_TRANSACTION_HALT; + else + val &= ~SCB_CONTROL_TRANSACTION_HALT; + img_i2c_writel(i2c, SCB_CONTROL_REG, val); +} + +/* Drain data from the FIFO into the buffer (automatic mode) */ +static void img_i2c_read_fifo(struct img_i2c *i2c) +{ + while (i2c->msg.len) { + u32 fifo_status; + u8 data; + + img_i2c_wr_rd_fence(i2c); + fifo_status = img_i2c_readl(i2c, SCB_FIFO_STATUS_REG); + if (fifo_status & FIFO_READ_EMPTY) + break; + + data = img_i2c_readl(i2c, SCB_READ_DATA_REG); + *i2c->msg.buf = data; + + img_i2c_writel(i2c, SCB_READ_FIFO_REG, 0xff); + i2c->msg.len--; + i2c->msg.buf++; + } +} + +/* Fill the FIFO with data from the buffer (automatic mode) */ +static void img_i2c_write_fifo(struct img_i2c *i2c) +{ + while (i2c->msg.len) { + u32 fifo_status; + + img_i2c_wr_rd_fence(i2c); + fifo_status = img_i2c_readl(i2c, SCB_FIFO_STATUS_REG); + if (fifo_status & FIFO_WRITE_FULL) + break; + + img_i2c_writel(i2c, SCB_WRITE_DATA_REG, *i2c->msg.buf); + i2c->msg.len--; + i2c->msg.buf++; + } + + /* Disable fifo emptying interrupt if nothing more to write */ + if (!i2c->msg.len) + i2c->int_enable &= ~INT_FIFO_EMPTYING; +} + +/* Start a read transaction in automatic mode */ +static void img_i2c_read(struct img_i2c *i2c) +{ + img_i2c_switch_mode(i2c, MODE_AUTOMATIC); + if (!i2c->last_msg) + i2c->int_enable |= INT_SLAVE_EVENT; + + img_i2c_writel(i2c, SCB_INT_MASK_REG, i2c->int_enable); + img_i2c_writel(i2c, SCB_READ_ADDR_REG, i2c->msg.addr); + img_i2c_writel(i2c, SCB_READ_COUNT_REG, i2c->msg.len); + + mod_timer(&i2c->check_timer, jiffies + msecs_to_jiffies(1)); +} + +/* Start a write transaction in automatic mode */ +static void img_i2c_write(struct img_i2c *i2c) +{ + img_i2c_switch_mode(i2c, MODE_AUTOMATIC); + if (!i2c->last_msg) + i2c->int_enable |= INT_SLAVE_EVENT; + + img_i2c_writel(i2c, SCB_WRITE_ADDR_REG, i2c->msg.addr); + img_i2c_writel(i2c, SCB_WRITE_COUNT_REG, i2c->msg.len); + + mod_timer(&i2c->check_timer, jiffies + msecs_to_jiffies(1)); + img_i2c_write_fifo(i2c); + + /* img_i2c_write_fifo() may modify int_enable */ + img_i2c_writel(i2c, SCB_INT_MASK_REG, i2c->int_enable); +} + +/* + * Indicate that the transaction is complete. This is called from the + * ISR to wake up the waiting thread, after which the ISR must not + * access any more SCB registers. + */ +static void img_i2c_complete_transaction(struct img_i2c *i2c, int status) +{ + img_i2c_switch_mode(i2c, MODE_INACTIVE); + if (status) { + i2c->msg_status = status; + img_i2c_transaction_halt(i2c, false); + } + complete(&i2c->msg_complete); +} + +static unsigned int img_i2c_raw_atomic_delay_handler(struct img_i2c *i2c, + u32 int_status, u32 line_status) +{ + /* Stay in raw mode for this, so we don't just loop infinitely */ + img_i2c_atomic_op(i2c, i2c->at_cur_cmd, i2c->at_cur_data); + img_i2c_switch_mode(i2c, MODE_ATOMIC); + return 0; +} + +static unsigned int img_i2c_raw(struct img_i2c *i2c, u32 int_status, + u32 line_status) +{ + if (int_status & INT_TIMING) { + if (i2c->raw_timeout == 0) + return img_i2c_raw_atomic_delay_handler(i2c, + int_status, line_status); + --i2c->raw_timeout; + } + return 0; +} + +static unsigned int img_i2c_sequence(struct img_i2c *i2c, u32 int_status) +{ + static const unsigned int continue_bits[] = { + [CMD_GEN_START] = LINESTAT_START_BIT_DET, + [CMD_GEN_DATA] = LINESTAT_INPUT_HELD_V, + [CMD_RET_ACK] = LINESTAT_ACK_DET | LINESTAT_NACK_DET, + [CMD_RET_DATA] = LINESTAT_INPUT_HELD_V, + [CMD_GEN_STOP] = LINESTAT_STOP_BIT_DET, + }; + int next_cmd = -1; + u8 next_data = 0x00; + + if (int_status & INT_SLAVE_EVENT) + i2c->at_slave_event = true; + if (int_status & INT_TRANSACTION_DONE) + i2c->at_t_done = true; + + if (!i2c->at_slave_event || !i2c->at_t_done) + return 0; + + /* wait if no continue bits are set */ + if (i2c->at_cur_cmd >= 0 && + i2c->at_cur_cmd < ARRAY_SIZE(continue_bits)) { + unsigned int cont_bits = continue_bits[i2c->at_cur_cmd]; + + if (cont_bits) { + cont_bits |= LINESTAT_ABORT_DET; + if (!(i2c->line_status & cont_bits)) + return 0; + } + } + + /* follow the sequence of commands in i2c->seq */ + next_cmd = *i2c->seq; + /* stop on a nil */ + if (!next_cmd) { + img_i2c_writel(i2c, SCB_OVERRIDE_REG, 0); + return ISR_COMPLETE(0); + } + /* when generating data, the next byte is the data */ + if (next_cmd == CMD_GEN_DATA) { + ++i2c->seq; + next_data = *i2c->seq; + } + ++i2c->seq; + img_i2c_atomic_op(i2c, next_cmd, next_data); + + return 0; +} + +static void img_i2c_reset_start(struct img_i2c *i2c) +{ + /* Initiate the magic dance */ + img_i2c_switch_mode(i2c, MODE_SEQUENCE); + img_i2c_writel(i2c, SCB_INT_MASK_REG, i2c->int_enable); + i2c->seq = img_i2c_reset_seq; + i2c->at_slave_event = true; + i2c->at_t_done = true; + i2c->at_cur_cmd = -1; + + /* img_i2c_reset_seq isn't empty so the following won't fail */ + img_i2c_sequence(i2c, 0); +} + +static void img_i2c_stop_start(struct img_i2c *i2c) +{ + /* Initiate a stop bit sequence */ + img_i2c_switch_mode(i2c, MODE_SEQUENCE); + img_i2c_writel(i2c, SCB_INT_MASK_REG, i2c->int_enable); + i2c->seq = img_i2c_stop_seq; + i2c->at_slave_event = true; + i2c->at_t_done = true; + i2c->at_cur_cmd = -1; + + /* img_i2c_stop_seq isn't empty so the following won't fail */ + img_i2c_sequence(i2c, 0); +} + +static unsigned int img_i2c_atomic(struct img_i2c *i2c, + u32 int_status, + u32 line_status) +{ + int next_cmd = -1; + u8 next_data = 0x00; + + if (int_status & INT_SLAVE_EVENT) + i2c->at_slave_event = true; + if (int_status & INT_TRANSACTION_DONE) + i2c->at_t_done = true; + + if (!i2c->at_slave_event || !i2c->at_t_done) + goto next_atomic_cmd; + if (i2c->line_status & LINESTAT_ABORT_DET) { + dev_dbg(i2c->adap.dev.parent, "abort condition detected\n"); + next_cmd = CMD_GEN_STOP; + i2c->msg_status = -EIO; + goto next_atomic_cmd; + } + + /* i2c->at_cur_cmd may have completed */ + switch (i2c->at_cur_cmd) { + case CMD_GEN_START: + next_cmd = CMD_GEN_DATA; + next_data = i2c_8bit_addr_from_msg(&i2c->msg); + break; + case CMD_GEN_DATA: + if (i2c->line_status & LINESTAT_INPUT_HELD_V) + next_cmd = CMD_RET_ACK; + break; + case CMD_RET_ACK: + if (i2c->line_status & LINESTAT_ACK_DET || + (i2c->line_status & LINESTAT_NACK_DET && + i2c->msg.flags & I2C_M_IGNORE_NAK)) { + if (i2c->msg.len == 0) { + next_cmd = CMD_GEN_STOP; + } else if (i2c->msg.flags & I2C_M_RD) { + next_cmd = CMD_RET_DATA; + } else { + next_cmd = CMD_GEN_DATA; + next_data = *i2c->msg.buf; + --i2c->msg.len; + ++i2c->msg.buf; + } + } else if (i2c->line_status & LINESTAT_NACK_DET) { + i2c->msg_status = -EIO; + next_cmd = CMD_GEN_STOP; + } + break; + case CMD_RET_DATA: + if (i2c->line_status & LINESTAT_INPUT_HELD_V) { + *i2c->msg.buf = (i2c->line_status & + LINESTAT_INPUT_DATA) + >> LINESTAT_INPUT_DATA_SHIFT; + --i2c->msg.len; + ++i2c->msg.buf; + if (i2c->msg.len) + next_cmd = CMD_GEN_ACK; + else + next_cmd = CMD_GEN_NACK; + } + break; + case CMD_GEN_ACK: + if (i2c->line_status & LINESTAT_ACK_DET) { + next_cmd = CMD_RET_DATA; + } else { + i2c->msg_status = -EIO; + next_cmd = CMD_GEN_STOP; + } + break; + case CMD_GEN_NACK: + next_cmd = CMD_GEN_STOP; + break; + case CMD_GEN_STOP: + img_i2c_writel(i2c, SCB_OVERRIDE_REG, 0); + return ISR_COMPLETE(0); + default: + dev_err(i2c->adap.dev.parent, "bad atomic command %d\n", + i2c->at_cur_cmd); + i2c->msg_status = -EIO; + next_cmd = CMD_GEN_STOP; + break; + } + +next_atomic_cmd: + if (next_cmd != -1) { + /* don't actually stop unless we're the last transaction */ + if (next_cmd == CMD_GEN_STOP && !i2c->msg_status && + !i2c->last_msg) + return ISR_COMPLETE(0); + img_i2c_atomic_op(i2c, next_cmd, next_data); + } + return 0; +} + +/* + * Timer function to check if something has gone wrong in automatic mode (so we + * don't have to handle so many interrupts just to catch an exception). + */ +static void img_i2c_check_timer(struct timer_list *t) +{ + struct img_i2c *i2c = from_timer(i2c, t, check_timer); + unsigned long flags; + unsigned int line_status; + + spin_lock_irqsave(&i2c->lock, flags); + line_status = img_i2c_readl(i2c, SCB_STATUS_REG); + + /* check for an abort condition */ + if (line_status & LINESTAT_ABORT_DET) { + dev_dbg(i2c->adap.dev.parent, + "abort condition detected by check timer\n"); + /* enable slave event interrupt mask to trigger irq */ + img_i2c_writel(i2c, SCB_INT_MASK_REG, + i2c->int_enable | INT_SLAVE_EVENT); + } + + spin_unlock_irqrestore(&i2c->lock, flags); +} + +static unsigned int img_i2c_auto(struct img_i2c *i2c, + unsigned int int_status, + unsigned int line_status) +{ + if (int_status & (INT_WRITE_ACK_ERR | INT_ADDR_ACK_ERR)) + return ISR_COMPLETE(EIO); + + if (line_status & LINESTAT_ABORT_DET) { + dev_dbg(i2c->adap.dev.parent, "abort condition detected\n"); + /* empty the read fifo */ + if ((i2c->msg.flags & I2C_M_RD) && + (int_status & INT_FIFO_FULL_FILLING)) + img_i2c_read_fifo(i2c); + /* use atomic mode and try to force a stop bit */ + i2c->msg_status = -EIO; + img_i2c_stop_start(i2c); + return 0; + } + + /* Enable transaction halt on start bit */ + if (!i2c->last_msg && line_status & LINESTAT_START_BIT_DET) { + img_i2c_transaction_halt(i2c, !i2c->last_msg); + /* we're no longer interested in the slave event */ + i2c->int_enable &= ~INT_SLAVE_EVENT; + } + + mod_timer(&i2c->check_timer, jiffies + msecs_to_jiffies(1)); + + if (int_status & INT_STOP_DETECTED) { + /* Drain remaining data in FIFO and complete transaction */ + if (i2c->msg.flags & I2C_M_RD) + img_i2c_read_fifo(i2c); + return ISR_COMPLETE(0); + } + + if (i2c->msg.flags & I2C_M_RD) { + if (int_status & (INT_FIFO_FULL_FILLING | INT_MASTER_HALTED)) { + img_i2c_read_fifo(i2c); + if (i2c->msg.len == 0) + return ISR_WAITSTOP; + } + } else { + if (int_status & (INT_FIFO_EMPTY | INT_MASTER_HALTED)) { + if ((int_status & INT_FIFO_EMPTY) && + i2c->msg.len == 0) + return ISR_WAITSTOP; + img_i2c_write_fifo(i2c); + } + } + if (int_status & INT_MASTER_HALTED) { + /* + * Release and then enable transaction halt, to + * allow only a single byte to proceed. + */ + img_i2c_transaction_halt(i2c, false); + img_i2c_transaction_halt(i2c, !i2c->last_msg); + } + + return 0; +} + +static irqreturn_t img_i2c_isr(int irq, void *dev_id) +{ + struct img_i2c *i2c = dev_id; + u32 int_status, line_status; + /* We handle transaction completion AFTER accessing registers */ + unsigned int hret; + + /* Read interrupt status register. */ + int_status = img_i2c_readl(i2c, SCB_INT_STATUS_REG); + /* Clear detected interrupts. */ + img_i2c_writel(i2c, SCB_INT_CLEAR_REG, int_status); + + /* + * Read line status and clear it until it actually is clear. We have + * to be careful not to lose any line status bits that get latched. + */ + line_status = img_i2c_readl(i2c, SCB_STATUS_REG); + if (line_status & LINESTAT_LATCHED) { + img_i2c_writel(i2c, SCB_CLEAR_REG, + (line_status & LINESTAT_LATCHED) + >> LINESTAT_CLEAR_SHIFT); + img_i2c_wr_rd_fence(i2c); + } + + spin_lock(&i2c->lock); + + /* Keep track of line status bits received */ + i2c->line_status &= ~LINESTAT_INPUT_DATA; + i2c->line_status |= line_status; + + /* + * Certain interrupts indicate that sclk low timeout is not + * a problem. If any of these are set, just continue. + */ + if ((int_status & INT_SCLK_LOW_TIMEOUT) && + !(int_status & (INT_SLAVE_EVENT | + INT_FIFO_EMPTY | + INT_FIFO_FULL))) { + dev_crit(i2c->adap.dev.parent, + "fatal: clock low timeout occurred %s addr 0x%02x\n", + (i2c->msg.flags & I2C_M_RD) ? "reading" : "writing", + i2c->msg.addr); + hret = ISR_FATAL(EIO); + goto out; + } + + if (i2c->mode == MODE_ATOMIC) + hret = img_i2c_atomic(i2c, int_status, line_status); + else if (i2c->mode == MODE_AUTOMATIC) + hret = img_i2c_auto(i2c, int_status, line_status); + else if (i2c->mode == MODE_SEQUENCE) + hret = img_i2c_sequence(i2c, int_status); + else if (i2c->mode == MODE_WAITSTOP && (int_status & INT_SLAVE_EVENT) && + (line_status & LINESTAT_STOP_BIT_DET)) + hret = ISR_COMPLETE(0); + else if (i2c->mode == MODE_RAW) + hret = img_i2c_raw(i2c, int_status, line_status); + else + hret = 0; + + /* Clear detected level interrupts. */ + img_i2c_writel(i2c, SCB_INT_CLEAR_REG, int_status & INT_LEVEL); + +out: + if (hret & ISR_WAITSTOP) { + /* + * Only wait for stop on last message. + * Also we may already have detected the stop bit. + */ + if (!i2c->last_msg || i2c->line_status & LINESTAT_STOP_BIT_DET) + hret = ISR_COMPLETE(0); + else + img_i2c_switch_mode(i2c, MODE_WAITSTOP); + } + + /* now we've finished using regs, handle transaction completion */ + if (hret & ISR_COMPLETE_M) { + int status = -(hret & ISR_STATUS_M); + + img_i2c_complete_transaction(i2c, status); + if (hret & ISR_FATAL_M) + img_i2c_switch_mode(i2c, MODE_FATAL); + } + + /* Enable interrupts (int_enable may be altered by changing mode) */ + img_i2c_writel(i2c, SCB_INT_MASK_REG, i2c->int_enable); + + spin_unlock(&i2c->lock); + + return IRQ_HANDLED; +} + +/* Force a bus reset sequence and wait for it to complete */ +static int img_i2c_reset_bus(struct img_i2c *i2c) +{ + unsigned long flags; + unsigned long time_left; + + spin_lock_irqsave(&i2c->lock, flags); + reinit_completion(&i2c->msg_complete); + img_i2c_reset_start(i2c); + spin_unlock_irqrestore(&i2c->lock, flags); + + time_left = wait_for_completion_timeout(&i2c->msg_complete, + IMG_I2C_TIMEOUT); + if (time_left == 0) + return -ETIMEDOUT; + return 0; +} + +static int img_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct img_i2c *i2c = i2c_get_adapdata(adap); + bool atomic = false; + int i, ret; + unsigned long time_left; + + if (i2c->mode == MODE_SUSPEND) { + WARN(1, "refusing to service transaction in suspended state\n"); + return -EIO; + } + + if (i2c->mode == MODE_FATAL) + return -EIO; + + for (i = 0; i < num; i++) { + /* + * 0 byte reads are not possible because the slave could try + * and pull the data line low, preventing a stop bit. + */ + if (!msgs[i].len && msgs[i].flags & I2C_M_RD) + return -EIO; + /* + * 0 byte writes are possible and used for probing, but we + * cannot do them in automatic mode, so use atomic mode + * instead. + * + * Also, the I2C_M_IGNORE_NAK mode can only be implemented + * in atomic mode. + */ + if (!msgs[i].len || + (msgs[i].flags & I2C_M_IGNORE_NAK)) + atomic = true; + } + + ret = pm_runtime_resume_and_get(adap->dev.parent); + if (ret < 0) + return ret; + + for (i = 0; i < num; i++) { + struct i2c_msg *msg = &msgs[i]; + unsigned long flags; + + spin_lock_irqsave(&i2c->lock, flags); + + /* + * Make a copy of the message struct. We mustn't modify the + * original or we'll confuse drivers and i2c-dev. + */ + i2c->msg = *msg; + i2c->msg_status = 0; + + /* + * After the last message we must have waited for a stop bit. + * Not waiting can cause problems when the clock is disabled + * before the stop bit is sent, and the linux I2C interface + * requires separate transfers not to joined with repeated + * start. + */ + i2c->last_msg = (i == num - 1); + reinit_completion(&i2c->msg_complete); + + /* + * Clear line status and all interrupts before starting a + * transfer, as we may have unserviced interrupts from + * previous transfers that might be handled in the context + * of the new transfer. + */ + img_i2c_writel(i2c, SCB_INT_CLEAR_REG, ~0); + img_i2c_writel(i2c, SCB_CLEAR_REG, ~0); + + if (atomic) { + img_i2c_atomic_start(i2c); + } else { + /* + * Enable transaction halt if not the last message in + * the queue so that we can control repeated starts. + */ + img_i2c_transaction_halt(i2c, !i2c->last_msg); + + if (msg->flags & I2C_M_RD) + img_i2c_read(i2c); + else + img_i2c_write(i2c); + + /* + * Release and then enable transaction halt, to + * allow only a single byte to proceed. + * This doesn't have an effect on the initial transfer + * but will allow the following transfers to start + * processing if the previous transfer was marked as + * complete while the i2c block was halted. + */ + img_i2c_transaction_halt(i2c, false); + img_i2c_transaction_halt(i2c, !i2c->last_msg); + } + spin_unlock_irqrestore(&i2c->lock, flags); + + time_left = wait_for_completion_timeout(&i2c->msg_complete, + IMG_I2C_TIMEOUT); + del_timer_sync(&i2c->check_timer); + + if (time_left == 0) { + dev_err(adap->dev.parent, "i2c transfer timed out\n"); + i2c->msg_status = -ETIMEDOUT; + break; + } + + if (i2c->msg_status) + break; + } + + pm_runtime_mark_last_busy(adap->dev.parent); + pm_runtime_put_autosuspend(adap->dev.parent); + + return i2c->msg_status ? i2c->msg_status : num; +} + +static u32 img_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm img_i2c_algo = { + .master_xfer = img_i2c_xfer, + .functionality = img_i2c_func, +}; + +static int img_i2c_init(struct img_i2c *i2c) +{ + unsigned int clk_khz, bitrate_khz, clk_period, tckh, tckl, tsdh; + unsigned int i, data, prescale, inc, int_bitrate, filt; + struct img_i2c_timings timing; + u32 rev; + int ret; + + ret = pm_runtime_resume_and_get(i2c->adap.dev.parent); + if (ret < 0) + return ret; + + rev = img_i2c_readl(i2c, SCB_CORE_REV_REG); + if ((rev & 0x00ffffff) < 0x00020200) { + dev_info(i2c->adap.dev.parent, + "Unknown hardware revision (%d.%d.%d.%d)\n", + (rev >> 24) & 0xff, (rev >> 16) & 0xff, + (rev >> 8) & 0xff, rev & 0xff); + pm_runtime_mark_last_busy(i2c->adap.dev.parent); + pm_runtime_put_autosuspend(i2c->adap.dev.parent); + return -EINVAL; + } + + /* Fencing enabled by default. */ + i2c->need_wr_rd_fence = true; + + /* Determine what mode we're in from the bitrate */ + timing = timings[0]; + for (i = 0; i < ARRAY_SIZE(timings); i++) { + if (i2c->bitrate <= timings[i].max_bitrate) { + timing = timings[i]; + break; + } + } + if (i2c->bitrate > timings[ARRAY_SIZE(timings) - 1].max_bitrate) { + dev_warn(i2c->adap.dev.parent, + "requested bitrate (%u) is higher than the max bitrate supported (%u)\n", + i2c->bitrate, + timings[ARRAY_SIZE(timings) - 1].max_bitrate); + timing = timings[ARRAY_SIZE(timings) - 1]; + i2c->bitrate = timing.max_bitrate; + } + + bitrate_khz = i2c->bitrate / 1000; + clk_khz = clk_get_rate(i2c->scb_clk) / 1000; + + /* Find the prescale that would give us that inc (approx delay = 0) */ + prescale = SCB_OPT_INC * clk_khz / (256 * 16 * bitrate_khz); + prescale = clamp_t(unsigned int, prescale, 1, 8); + clk_khz /= prescale; + + /* Setup the clock increment value */ + inc = (256 * 16 * bitrate_khz) / clk_khz; + + /* + * The clock generation logic allows to filter glitches on the bus. + * This filter is able to remove bus glitches shorter than 50ns. + * If the clock enable rate is greater than 20 MHz, no filtering + * is required, so we need to disable it. + * If it's between the 20-40 MHz range, there's no need to divide + * the clock to get a filter. + */ + if (clk_khz < 20000) { + filt = SCB_FILT_DISABLE; + } else if (clk_khz < 40000) { + filt = SCB_FILT_BYPASS; + } else { + /* Calculate filter clock */ + filt = (64000 / ((clk_khz / 1000) * SCB_FILT_GLITCH)); + + /* Scale up if needed */ + if (64000 % ((clk_khz / 1000) * SCB_FILT_GLITCH)) + inc++; + + if (filt > SCB_FILT_INC_MASK) + filt = SCB_FILT_INC_MASK; + + filt = (filt & SCB_FILT_INC_MASK) << SCB_FILT_INC_SHIFT; + } + data = filt | ((inc & SCB_INC_MASK) << SCB_INC_SHIFT) | (prescale - 1); + img_i2c_writel(i2c, SCB_CLK_SET_REG, data); + + /* Obtain the clock period of the fx16 clock in ns */ + clk_period = (256 * 1000000) / (clk_khz * inc); + + /* Calculate the bitrate in terms of internal clock pulses */ + int_bitrate = 1000000 / (bitrate_khz * clk_period); + if ((1000000 % (bitrate_khz * clk_period)) >= + ((bitrate_khz * clk_period) / 2)) + int_bitrate++; + + /* + * Setup clock duty cycle, start with 50% and adjust TCKH and TCKL + * values from there if they don't meet minimum timing requirements + */ + tckh = int_bitrate / 2; + tckl = int_bitrate - tckh; + + /* Adjust TCKH and TCKL values */ + data = DIV_ROUND_UP(timing.tckl, clk_period); + + if (tckl < data) { + tckl = data; + tckh = int_bitrate - tckl; + } + + if (tckh > 0) + --tckh; + + if (tckl > 0) + --tckl; + + img_i2c_writel(i2c, SCB_TIME_TCKH_REG, tckh); + img_i2c_writel(i2c, SCB_TIME_TCKL_REG, tckl); + + /* Setup TSDH value */ + tsdh = DIV_ROUND_UP(timing.tsdh, clk_period); + + if (tsdh > 1) + data = tsdh - 1; + else + data = 0x01; + img_i2c_writel(i2c, SCB_TIME_TSDH_REG, data); + + /* This value is used later */ + tsdh = data; + + /* Setup TPL value */ + data = timing.tpl / clk_period; + if (data > 0) + --data; + img_i2c_writel(i2c, SCB_TIME_TPL_REG, data); + + /* Setup TPH value */ + data = timing.tph / clk_period; + if (data > 0) + --data; + img_i2c_writel(i2c, SCB_TIME_TPH_REG, data); + + /* Setup TSDL value to TPL + TSDH + 2 */ + img_i2c_writel(i2c, SCB_TIME_TSDL_REG, data + tsdh + 2); + + /* Setup TP2S value */ + data = timing.tp2s / clk_period; + if (data > 0) + --data; + img_i2c_writel(i2c, SCB_TIME_TP2S_REG, data); + + img_i2c_writel(i2c, SCB_TIME_TBI_REG, TIMEOUT_TBI); + img_i2c_writel(i2c, SCB_TIME_TSL_REG, TIMEOUT_TSL); + img_i2c_writel(i2c, SCB_TIME_TDL_REG, TIMEOUT_TDL); + + /* Take module out of soft reset and enable clocks */ + img_i2c_soft_reset(i2c); + + /* Disable all interrupts */ + img_i2c_writel(i2c, SCB_INT_MASK_REG, 0); + + /* Clear all interrupts */ + img_i2c_writel(i2c, SCB_INT_CLEAR_REG, ~0); + + /* Clear the scb_line_status events */ + img_i2c_writel(i2c, SCB_CLEAR_REG, ~0); + + /* Enable interrupts */ + img_i2c_writel(i2c, SCB_INT_MASK_REG, i2c->int_enable); + + /* Perform a synchronous sequence to reset the bus */ + ret = img_i2c_reset_bus(i2c); + + pm_runtime_mark_last_busy(i2c->adap.dev.parent); + pm_runtime_put_autosuspend(i2c->adap.dev.parent); + + return ret; +} + +static int img_i2c_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct img_i2c *i2c; + int irq, ret; + u32 val; + + i2c = devm_kzalloc(&pdev->dev, sizeof(struct img_i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c->base)) + return PTR_ERR(i2c->base); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + i2c->sys_clk = devm_clk_get(&pdev->dev, "sys"); + if (IS_ERR(i2c->sys_clk)) { + dev_err(&pdev->dev, "can't get system clock\n"); + return PTR_ERR(i2c->sys_clk); + } + + i2c->scb_clk = devm_clk_get(&pdev->dev, "scb"); + if (IS_ERR(i2c->scb_clk)) { + dev_err(&pdev->dev, "can't get core clock\n"); + return PTR_ERR(i2c->scb_clk); + } + + ret = devm_request_irq(&pdev->dev, irq, img_i2c_isr, 0, + pdev->name, i2c); + if (ret) { + dev_err(&pdev->dev, "can't request irq %d\n", irq); + return ret; + } + + /* Set up the exception check timer */ + timer_setup(&i2c->check_timer, img_i2c_check_timer, 0); + + i2c->bitrate = timings[0].max_bitrate; + if (!of_property_read_u32(node, "clock-frequency", &val)) + i2c->bitrate = val; + + i2c_set_adapdata(&i2c->adap, i2c); + i2c->adap.dev.parent = &pdev->dev; + i2c->adap.dev.of_node = node; + i2c->adap.owner = THIS_MODULE; + i2c->adap.algo = &img_i2c_algo; + i2c->adap.retries = 5; + i2c->adap.nr = pdev->id; + snprintf(i2c->adap.name, sizeof(i2c->adap.name), "IMG SCB I2C"); + + img_i2c_switch_mode(i2c, MODE_INACTIVE); + spin_lock_init(&i2c->lock); + init_completion(&i2c->msg_complete); + + platform_set_drvdata(pdev, i2c); + + pm_runtime_set_autosuspend_delay(&pdev->dev, IMG_I2C_PM_TIMEOUT); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_enable(&pdev->dev); + if (!pm_runtime_enabled(&pdev->dev)) { + ret = img_i2c_runtime_resume(&pdev->dev); + if (ret) + return ret; + } + + ret = img_i2c_init(i2c); + if (ret) + goto rpm_disable; + + ret = i2c_add_numbered_adapter(&i2c->adap); + if (ret < 0) + goto rpm_disable; + + return 0; + +rpm_disable: + if (!pm_runtime_enabled(&pdev->dev)) + img_i2c_runtime_suspend(&pdev->dev); + pm_runtime_disable(&pdev->dev); + pm_runtime_dont_use_autosuspend(&pdev->dev); + return ret; +} + +static void img_i2c_remove(struct platform_device *dev) +{ + struct img_i2c *i2c = platform_get_drvdata(dev); + + i2c_del_adapter(&i2c->adap); + pm_runtime_disable(&dev->dev); + if (!pm_runtime_status_suspended(&dev->dev)) + img_i2c_runtime_suspend(&dev->dev); +} + +static int img_i2c_runtime_suspend(struct device *dev) +{ + struct img_i2c *i2c = dev_get_drvdata(dev); + + clk_disable_unprepare(i2c->scb_clk); + clk_disable_unprepare(i2c->sys_clk); + + return 0; +} + +static int img_i2c_runtime_resume(struct device *dev) +{ + struct img_i2c *i2c = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(i2c->sys_clk); + if (ret) { + dev_err(dev, "Unable to enable sys clock\n"); + return ret; + } + + ret = clk_prepare_enable(i2c->scb_clk); + if (ret) { + dev_err(dev, "Unable to enable scb clock\n"); + clk_disable_unprepare(i2c->sys_clk); + return ret; + } + + return 0; +} + +static int img_i2c_suspend(struct device *dev) +{ + struct img_i2c *i2c = dev_get_drvdata(dev); + int ret; + + ret = pm_runtime_force_suspend(dev); + if (ret) + return ret; + + img_i2c_switch_mode(i2c, MODE_SUSPEND); + + return 0; +} + +static int img_i2c_resume(struct device *dev) +{ + struct img_i2c *i2c = dev_get_drvdata(dev); + int ret; + + ret = pm_runtime_force_resume(dev); + if (ret) + return ret; + + img_i2c_init(i2c); + + return 0; +} + +static const struct dev_pm_ops img_i2c_pm = { + RUNTIME_PM_OPS(img_i2c_runtime_suspend, img_i2c_runtime_resume, NULL) + SYSTEM_SLEEP_PM_OPS(img_i2c_suspend, img_i2c_resume) +}; + +static const struct of_device_id img_scb_i2c_match[] = { + { .compatible = "img,scb-i2c" }, + { } +}; +MODULE_DEVICE_TABLE(of, img_scb_i2c_match); + +static struct platform_driver img_scb_i2c_driver = { + .driver = { + .name = "img-i2c-scb", + .of_match_table = img_scb_i2c_match, + .pm = pm_ptr(&img_i2c_pm), + }, + .probe = img_i2c_probe, + .remove_new = img_i2c_remove, +}; +module_platform_driver(img_scb_i2c_driver); + +MODULE_AUTHOR("James Hogan <jhogan@kernel.org>"); +MODULE_DESCRIPTION("IMG host I2C driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c b/drivers/i2c/busses/i2c-imx-lpi2c.c new file mode 100644 index 000000000..678b30e90 --- /dev/null +++ b/drivers/i2c/busses/i2c-imx-lpi2c.c @@ -0,0 +1,678 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * This is i.MX low power i2c controller driver. + * + * Copyright 2016 Freescale Semiconductor, Inc. + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/sched.h> +#include <linux/slab.h> + +#define DRIVER_NAME "imx-lpi2c" + +#define LPI2C_PARAM 0x04 /* i2c RX/TX FIFO size */ +#define LPI2C_MCR 0x10 /* i2c contrl register */ +#define LPI2C_MSR 0x14 /* i2c status register */ +#define LPI2C_MIER 0x18 /* i2c interrupt enable */ +#define LPI2C_MCFGR0 0x20 /* i2c master configuration */ +#define LPI2C_MCFGR1 0x24 /* i2c master configuration */ +#define LPI2C_MCFGR2 0x28 /* i2c master configuration */ +#define LPI2C_MCFGR3 0x2C /* i2c master configuration */ +#define LPI2C_MCCR0 0x48 /* i2c master clk configuration */ +#define LPI2C_MCCR1 0x50 /* i2c master clk configuration */ +#define LPI2C_MFCR 0x58 /* i2c master FIFO control */ +#define LPI2C_MFSR 0x5C /* i2c master FIFO status */ +#define LPI2C_MTDR 0x60 /* i2c master TX data register */ +#define LPI2C_MRDR 0x70 /* i2c master RX data register */ + +/* i2c command */ +#define TRAN_DATA 0X00 +#define RECV_DATA 0X01 +#define GEN_STOP 0X02 +#define RECV_DISCARD 0X03 +#define GEN_START 0X04 +#define START_NACK 0X05 +#define START_HIGH 0X06 +#define START_HIGH_NACK 0X07 + +#define MCR_MEN BIT(0) +#define MCR_RST BIT(1) +#define MCR_DOZEN BIT(2) +#define MCR_DBGEN BIT(3) +#define MCR_RTF BIT(8) +#define MCR_RRF BIT(9) +#define MSR_TDF BIT(0) +#define MSR_RDF BIT(1) +#define MSR_SDF BIT(9) +#define MSR_NDF BIT(10) +#define MSR_ALF BIT(11) +#define MSR_MBF BIT(24) +#define MSR_BBF BIT(25) +#define MIER_TDIE BIT(0) +#define MIER_RDIE BIT(1) +#define MIER_SDIE BIT(9) +#define MIER_NDIE BIT(10) +#define MCFGR1_AUTOSTOP BIT(8) +#define MCFGR1_IGNACK BIT(9) +#define MRDR_RXEMPTY BIT(14) + +#define I2C_CLK_RATIO 2 +#define CHUNK_DATA 256 + +#define I2C_PM_TIMEOUT 10 /* ms */ + +enum lpi2c_imx_mode { + STANDARD, /* 100+Kbps */ + FAST, /* 400+Kbps */ + FAST_PLUS, /* 1.0+Mbps */ + HS, /* 3.4+Mbps */ + ULTRA_FAST, /* 5.0+Mbps */ +}; + +enum lpi2c_imx_pincfg { + TWO_PIN_OD, + TWO_PIN_OO, + TWO_PIN_PP, + FOUR_PIN_PP, +}; + +struct lpi2c_imx_struct { + struct i2c_adapter adapter; + int num_clks; + struct clk_bulk_data *clks; + void __iomem *base; + __u8 *rx_buf; + __u8 *tx_buf; + struct completion complete; + unsigned int msglen; + unsigned int delivered; + unsigned int block_data; + unsigned int bitrate; + unsigned int txfifosize; + unsigned int rxfifosize; + enum lpi2c_imx_mode mode; +}; + +static void lpi2c_imx_intctrl(struct lpi2c_imx_struct *lpi2c_imx, + unsigned int enable) +{ + writel(enable, lpi2c_imx->base + LPI2C_MIER); +} + +static int lpi2c_imx_bus_busy(struct lpi2c_imx_struct *lpi2c_imx) +{ + unsigned long orig_jiffies = jiffies; + unsigned int temp; + + while (1) { + temp = readl(lpi2c_imx->base + LPI2C_MSR); + + /* check for arbitration lost, clear if set */ + if (temp & MSR_ALF) { + writel(temp, lpi2c_imx->base + LPI2C_MSR); + return -EAGAIN; + } + + if (temp & (MSR_BBF | MSR_MBF)) + break; + + if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) { + dev_dbg(&lpi2c_imx->adapter.dev, "bus not work\n"); + return -ETIMEDOUT; + } + schedule(); + } + + return 0; +} + +static void lpi2c_imx_set_mode(struct lpi2c_imx_struct *lpi2c_imx) +{ + unsigned int bitrate = lpi2c_imx->bitrate; + enum lpi2c_imx_mode mode; + + if (bitrate < I2C_MAX_FAST_MODE_FREQ) + mode = STANDARD; + else if (bitrate < I2C_MAX_FAST_MODE_PLUS_FREQ) + mode = FAST; + else if (bitrate < I2C_MAX_HIGH_SPEED_MODE_FREQ) + mode = FAST_PLUS; + else if (bitrate < I2C_MAX_ULTRA_FAST_MODE_FREQ) + mode = HS; + else + mode = ULTRA_FAST; + + lpi2c_imx->mode = mode; +} + +static int lpi2c_imx_start(struct lpi2c_imx_struct *lpi2c_imx, + struct i2c_msg *msgs) +{ + unsigned int temp; + + temp = readl(lpi2c_imx->base + LPI2C_MCR); + temp |= MCR_RRF | MCR_RTF; + writel(temp, lpi2c_imx->base + LPI2C_MCR); + writel(0x7f00, lpi2c_imx->base + LPI2C_MSR); + + temp = i2c_8bit_addr_from_msg(msgs) | (GEN_START << 8); + writel(temp, lpi2c_imx->base + LPI2C_MTDR); + + return lpi2c_imx_bus_busy(lpi2c_imx); +} + +static void lpi2c_imx_stop(struct lpi2c_imx_struct *lpi2c_imx) +{ + unsigned long orig_jiffies = jiffies; + unsigned int temp; + + writel(GEN_STOP << 8, lpi2c_imx->base + LPI2C_MTDR); + + do { + temp = readl(lpi2c_imx->base + LPI2C_MSR); + if (temp & MSR_SDF) + break; + + if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) { + dev_dbg(&lpi2c_imx->adapter.dev, "stop timeout\n"); + break; + } + schedule(); + + } while (1); +} + +/* CLKLO = I2C_CLK_RATIO * CLKHI, SETHOLD = CLKHI, DATAVD = CLKHI/2 */ +static int lpi2c_imx_config(struct lpi2c_imx_struct *lpi2c_imx) +{ + u8 prescale, filt, sethold, datavd; + unsigned int clk_rate, clk_cycle, clkhi, clklo; + enum lpi2c_imx_pincfg pincfg; + unsigned int temp; + + lpi2c_imx_set_mode(lpi2c_imx); + + clk_rate = clk_get_rate(lpi2c_imx->clks[0].clk); + if (!clk_rate) + return -EINVAL; + + if (lpi2c_imx->mode == HS || lpi2c_imx->mode == ULTRA_FAST) + filt = 0; + else + filt = 2; + + for (prescale = 0; prescale <= 7; prescale++) { + clk_cycle = clk_rate / ((1 << prescale) * lpi2c_imx->bitrate) + - 3 - (filt >> 1); + clkhi = DIV_ROUND_UP(clk_cycle, I2C_CLK_RATIO + 1); + clklo = clk_cycle - clkhi; + if (clklo < 64) + break; + } + + if (prescale > 7) + return -EINVAL; + + /* set MCFGR1: PINCFG, PRESCALE, IGNACK */ + if (lpi2c_imx->mode == ULTRA_FAST) + pincfg = TWO_PIN_OO; + else + pincfg = TWO_PIN_OD; + temp = prescale | pincfg << 24; + + if (lpi2c_imx->mode == ULTRA_FAST) + temp |= MCFGR1_IGNACK; + + writel(temp, lpi2c_imx->base + LPI2C_MCFGR1); + + /* set MCFGR2: FILTSDA, FILTSCL */ + temp = (filt << 16) | (filt << 24); + writel(temp, lpi2c_imx->base + LPI2C_MCFGR2); + + /* set MCCR: DATAVD, SETHOLD, CLKHI, CLKLO */ + sethold = clkhi; + datavd = clkhi >> 1; + temp = datavd << 24 | sethold << 16 | clkhi << 8 | clklo; + + if (lpi2c_imx->mode == HS) + writel(temp, lpi2c_imx->base + LPI2C_MCCR1); + else + writel(temp, lpi2c_imx->base + LPI2C_MCCR0); + + return 0; +} + +static int lpi2c_imx_master_enable(struct lpi2c_imx_struct *lpi2c_imx) +{ + unsigned int temp; + int ret; + + ret = pm_runtime_resume_and_get(lpi2c_imx->adapter.dev.parent); + if (ret < 0) + return ret; + + temp = MCR_RST; + writel(temp, lpi2c_imx->base + LPI2C_MCR); + writel(0, lpi2c_imx->base + LPI2C_MCR); + + ret = lpi2c_imx_config(lpi2c_imx); + if (ret) + goto rpm_put; + + temp = readl(lpi2c_imx->base + LPI2C_MCR); + temp |= MCR_MEN; + writel(temp, lpi2c_imx->base + LPI2C_MCR); + + return 0; + +rpm_put: + pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent); + pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent); + + return ret; +} + +static int lpi2c_imx_master_disable(struct lpi2c_imx_struct *lpi2c_imx) +{ + u32 temp; + + temp = readl(lpi2c_imx->base + LPI2C_MCR); + temp &= ~MCR_MEN; + writel(temp, lpi2c_imx->base + LPI2C_MCR); + + pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent); + pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent); + + return 0; +} + +static int lpi2c_imx_msg_complete(struct lpi2c_imx_struct *lpi2c_imx) +{ + unsigned long timeout; + + timeout = wait_for_completion_timeout(&lpi2c_imx->complete, HZ); + + return timeout ? 0 : -ETIMEDOUT; +} + +static int lpi2c_imx_txfifo_empty(struct lpi2c_imx_struct *lpi2c_imx) +{ + unsigned long orig_jiffies = jiffies; + u32 txcnt; + + do { + txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff; + + if (readl(lpi2c_imx->base + LPI2C_MSR) & MSR_NDF) { + dev_dbg(&lpi2c_imx->adapter.dev, "NDF detected\n"); + return -EIO; + } + + if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) { + dev_dbg(&lpi2c_imx->adapter.dev, "txfifo empty timeout\n"); + return -ETIMEDOUT; + } + schedule(); + + } while (txcnt); + + return 0; +} + +static void lpi2c_imx_set_tx_watermark(struct lpi2c_imx_struct *lpi2c_imx) +{ + writel(lpi2c_imx->txfifosize >> 1, lpi2c_imx->base + LPI2C_MFCR); +} + +static void lpi2c_imx_set_rx_watermark(struct lpi2c_imx_struct *lpi2c_imx) +{ + unsigned int temp, remaining; + + remaining = lpi2c_imx->msglen - lpi2c_imx->delivered; + + if (remaining > (lpi2c_imx->rxfifosize >> 1)) + temp = lpi2c_imx->rxfifosize >> 1; + else + temp = 0; + + writel(temp << 16, lpi2c_imx->base + LPI2C_MFCR); +} + +static void lpi2c_imx_write_txfifo(struct lpi2c_imx_struct *lpi2c_imx) +{ + unsigned int data, txcnt; + + txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff; + + while (txcnt < lpi2c_imx->txfifosize) { + if (lpi2c_imx->delivered == lpi2c_imx->msglen) + break; + + data = lpi2c_imx->tx_buf[lpi2c_imx->delivered++]; + writel(data, lpi2c_imx->base + LPI2C_MTDR); + txcnt++; + } + + if (lpi2c_imx->delivered < lpi2c_imx->msglen) + lpi2c_imx_intctrl(lpi2c_imx, MIER_TDIE | MIER_NDIE); + else + complete(&lpi2c_imx->complete); +} + +static void lpi2c_imx_read_rxfifo(struct lpi2c_imx_struct *lpi2c_imx) +{ + unsigned int blocklen, remaining; + unsigned int temp, data; + + do { + data = readl(lpi2c_imx->base + LPI2C_MRDR); + if (data & MRDR_RXEMPTY) + break; + + lpi2c_imx->rx_buf[lpi2c_imx->delivered++] = data & 0xff; + } while (1); + + /* + * First byte is the length of remaining packet in the SMBus block + * data read. Add it to msgs->len. + */ + if (lpi2c_imx->block_data) { + blocklen = lpi2c_imx->rx_buf[0]; + lpi2c_imx->msglen += blocklen; + } + + remaining = lpi2c_imx->msglen - lpi2c_imx->delivered; + + if (!remaining) { + complete(&lpi2c_imx->complete); + return; + } + + /* not finished, still waiting for rx data */ + lpi2c_imx_set_rx_watermark(lpi2c_imx); + + /* multiple receive commands */ + if (lpi2c_imx->block_data) { + lpi2c_imx->block_data = 0; + temp = remaining; + temp |= (RECV_DATA << 8); + writel(temp, lpi2c_imx->base + LPI2C_MTDR); + } else if (!(lpi2c_imx->delivered & 0xff)) { + temp = (remaining > CHUNK_DATA ? CHUNK_DATA : remaining) - 1; + temp |= (RECV_DATA << 8); + writel(temp, lpi2c_imx->base + LPI2C_MTDR); + } + + lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE); +} + +static void lpi2c_imx_write(struct lpi2c_imx_struct *lpi2c_imx, + struct i2c_msg *msgs) +{ + lpi2c_imx->tx_buf = msgs->buf; + lpi2c_imx_set_tx_watermark(lpi2c_imx); + lpi2c_imx_write_txfifo(lpi2c_imx); +} + +static void lpi2c_imx_read(struct lpi2c_imx_struct *lpi2c_imx, + struct i2c_msg *msgs) +{ + unsigned int temp; + + lpi2c_imx->rx_buf = msgs->buf; + lpi2c_imx->block_data = msgs->flags & I2C_M_RECV_LEN; + + lpi2c_imx_set_rx_watermark(lpi2c_imx); + temp = msgs->len > CHUNK_DATA ? CHUNK_DATA - 1 : msgs->len - 1; + temp |= (RECV_DATA << 8); + writel(temp, lpi2c_imx->base + LPI2C_MTDR); + + lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE | MIER_NDIE); +} + +static int lpi2c_imx_xfer(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num) +{ + struct lpi2c_imx_struct *lpi2c_imx = i2c_get_adapdata(adapter); + unsigned int temp; + int i, result; + + result = lpi2c_imx_master_enable(lpi2c_imx); + if (result) + return result; + + for (i = 0; i < num; i++) { + result = lpi2c_imx_start(lpi2c_imx, &msgs[i]); + if (result) + goto disable; + + /* quick smbus */ + if (num == 1 && msgs[0].len == 0) + goto stop; + + lpi2c_imx->rx_buf = NULL; + lpi2c_imx->tx_buf = NULL; + lpi2c_imx->delivered = 0; + lpi2c_imx->msglen = msgs[i].len; + init_completion(&lpi2c_imx->complete); + + if (msgs[i].flags & I2C_M_RD) + lpi2c_imx_read(lpi2c_imx, &msgs[i]); + else + lpi2c_imx_write(lpi2c_imx, &msgs[i]); + + result = lpi2c_imx_msg_complete(lpi2c_imx); + if (result) + goto stop; + + if (!(msgs[i].flags & I2C_M_RD)) { + result = lpi2c_imx_txfifo_empty(lpi2c_imx); + if (result) + goto stop; + } + } + +stop: + lpi2c_imx_stop(lpi2c_imx); + + temp = readl(lpi2c_imx->base + LPI2C_MSR); + if ((temp & MSR_NDF) && !result) + result = -EIO; + +disable: + lpi2c_imx_master_disable(lpi2c_imx); + + dev_dbg(&lpi2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__, + (result < 0) ? "error" : "success msg", + (result < 0) ? result : num); + + return (result < 0) ? result : num; +} + +static irqreturn_t lpi2c_imx_isr(int irq, void *dev_id) +{ + struct lpi2c_imx_struct *lpi2c_imx = dev_id; + unsigned int enabled; + unsigned int temp; + + enabled = readl(lpi2c_imx->base + LPI2C_MIER); + + lpi2c_imx_intctrl(lpi2c_imx, 0); + temp = readl(lpi2c_imx->base + LPI2C_MSR); + temp &= enabled; + + if (temp & MSR_NDF) + complete(&lpi2c_imx->complete); + else if (temp & MSR_RDF) + lpi2c_imx_read_rxfifo(lpi2c_imx); + else if (temp & MSR_TDF) + lpi2c_imx_write_txfifo(lpi2c_imx); + + return IRQ_HANDLED; +} + +static u32 lpi2c_imx_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | + I2C_FUNC_SMBUS_READ_BLOCK_DATA; +} + +static const struct i2c_algorithm lpi2c_imx_algo = { + .master_xfer = lpi2c_imx_xfer, + .functionality = lpi2c_imx_func, +}; + +static const struct of_device_id lpi2c_imx_of_match[] = { + { .compatible = "fsl,imx7ulp-lpi2c" }, + { }, +}; +MODULE_DEVICE_TABLE(of, lpi2c_imx_of_match); + +static int lpi2c_imx_probe(struct platform_device *pdev) +{ + struct lpi2c_imx_struct *lpi2c_imx; + unsigned int temp; + int irq, ret; + + lpi2c_imx = devm_kzalloc(&pdev->dev, sizeof(*lpi2c_imx), GFP_KERNEL); + if (!lpi2c_imx) + return -ENOMEM; + + lpi2c_imx->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(lpi2c_imx->base)) + return PTR_ERR(lpi2c_imx->base); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + lpi2c_imx->adapter.owner = THIS_MODULE; + lpi2c_imx->adapter.algo = &lpi2c_imx_algo; + lpi2c_imx->adapter.dev.parent = &pdev->dev; + lpi2c_imx->adapter.dev.of_node = pdev->dev.of_node; + strscpy(lpi2c_imx->adapter.name, pdev->name, + sizeof(lpi2c_imx->adapter.name)); + + ret = devm_clk_bulk_get_all(&pdev->dev, &lpi2c_imx->clks); + if (ret < 0) + return dev_err_probe(&pdev->dev, ret, "can't get I2C peripheral clock\n"); + lpi2c_imx->num_clks = ret; + + ret = of_property_read_u32(pdev->dev.of_node, + "clock-frequency", &lpi2c_imx->bitrate); + if (ret) + lpi2c_imx->bitrate = I2C_MAX_STANDARD_MODE_FREQ; + + ret = devm_request_irq(&pdev->dev, irq, lpi2c_imx_isr, 0, + pdev->name, lpi2c_imx); + if (ret) + return dev_err_probe(&pdev->dev, ret, "can't claim irq %d\n", irq); + + i2c_set_adapdata(&lpi2c_imx->adapter, lpi2c_imx); + platform_set_drvdata(pdev, lpi2c_imx); + + ret = clk_bulk_prepare_enable(lpi2c_imx->num_clks, lpi2c_imx->clks); + if (ret) + return ret; + + pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_get_noresume(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + temp = readl(lpi2c_imx->base + LPI2C_PARAM); + lpi2c_imx->txfifosize = 1 << (temp & 0x0f); + lpi2c_imx->rxfifosize = 1 << ((temp >> 8) & 0x0f); + + ret = i2c_add_adapter(&lpi2c_imx->adapter); + if (ret) + goto rpm_disable; + + pm_runtime_mark_last_busy(&pdev->dev); + pm_runtime_put_autosuspend(&pdev->dev); + + dev_info(&lpi2c_imx->adapter.dev, "LPI2C adapter registered\n"); + + return 0; + +rpm_disable: + pm_runtime_put(&pdev->dev); + pm_runtime_disable(&pdev->dev); + pm_runtime_dont_use_autosuspend(&pdev->dev); + + return ret; +} + +static void lpi2c_imx_remove(struct platform_device *pdev) +{ + struct lpi2c_imx_struct *lpi2c_imx = platform_get_drvdata(pdev); + + i2c_del_adapter(&lpi2c_imx->adapter); + + pm_runtime_disable(&pdev->dev); + pm_runtime_dont_use_autosuspend(&pdev->dev); +} + +static int __maybe_unused lpi2c_runtime_suspend(struct device *dev) +{ + struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev); + + clk_bulk_disable(lpi2c_imx->num_clks, lpi2c_imx->clks); + pinctrl_pm_select_sleep_state(dev); + + return 0; +} + +static int __maybe_unused lpi2c_runtime_resume(struct device *dev) +{ + struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev); + int ret; + + pinctrl_pm_select_default_state(dev); + ret = clk_bulk_enable(lpi2c_imx->num_clks, lpi2c_imx->clks); + if (ret) { + dev_err(dev, "failed to enable I2C clock, ret=%d\n", ret); + return ret; + } + + return 0; +} + +static const struct dev_pm_ops lpi2c_pm_ops = { + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) + SET_RUNTIME_PM_OPS(lpi2c_runtime_suspend, + lpi2c_runtime_resume, NULL) +}; + +static struct platform_driver lpi2c_imx_driver = { + .probe = lpi2c_imx_probe, + .remove_new = lpi2c_imx_remove, + .driver = { + .name = DRIVER_NAME, + .of_match_table = lpi2c_imx_of_match, + .pm = &lpi2c_pm_ops, + }, +}; + +module_platform_driver(lpi2c_imx_driver); + +MODULE_AUTHOR("Gao Pan <pandy.gao@nxp.com>"); +MODULE_DESCRIPTION("I2C adapter driver for LPI2C bus"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c new file mode 100644 index 000000000..1775a79ae --- /dev/null +++ b/drivers/i2c/busses/i2c-imx.c @@ -0,0 +1,1652 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2002 Motorola GSG-China + * + * Author: + * Darius Augulis, Teltonika Inc. + * + * Desc.: + * Implementation of I2C Adapter/Algorithm Driver + * for I2C Bus integrated in Freescale i.MX/MXC processors + * + * Derived from Motorola GSG China I2C example driver + * + * Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de + * Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de + * Copyright (C) 2007 RightHand Technologies, Inc. + * Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt> + * + * Copyright 2013 Freescale Semiconductor, Inc. + * Copyright 2020 NXP + * + */ + +#include <linux/acpi.h> +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/dmapool.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> +#include <linux/spinlock.h> +#include <linux/hrtimer.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_dma.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_data/i2c-imx.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/sched.h> +#include <linux/slab.h> + +/* This will be the driver name the kernel reports */ +#define DRIVER_NAME "imx-i2c" + +#define I2C_IMX_CHECK_DELAY 30000 /* Time to check for bus idle, in NS */ + +/* + * Enable DMA if transfer byte size is bigger than this threshold. + * As the hardware request, it must bigger than 4 bytes.\ + * I have set '16' here, maybe it's not the best but I think it's + * the appropriate. + */ +#define DMA_THRESHOLD 16 +#define DMA_TIMEOUT 1000 + +/* IMX I2C registers: + * the I2C register offset is different between SoCs, + * to provide support for all these chips, split the + * register offset into a fixed base address and a + * variable shift value, then the full register offset + * will be calculated by + * reg_off = ( reg_base_addr << reg_shift) + */ +#define IMX_I2C_IADR 0x00 /* i2c slave address */ +#define IMX_I2C_IFDR 0x01 /* i2c frequency divider */ +#define IMX_I2C_I2CR 0x02 /* i2c control */ +#define IMX_I2C_I2SR 0x03 /* i2c status */ +#define IMX_I2C_I2DR 0x04 /* i2c transfer data */ + +/* + * All of the layerscape series SoCs support IBIC register. + */ +#define IMX_I2C_IBIC 0x05 /* i2c bus interrupt config */ + +#define IMX_I2C_REGSHIFT 2 +#define VF610_I2C_REGSHIFT 0 + +/* Bits of IMX I2C registers */ +#define I2SR_RXAK 0x01 +#define I2SR_IIF 0x02 +#define I2SR_SRW 0x04 +#define I2SR_IAL 0x10 +#define I2SR_IBB 0x20 +#define I2SR_IAAS 0x40 +#define I2SR_ICF 0x80 +#define I2CR_DMAEN 0x02 +#define I2CR_RSTA 0x04 +#define I2CR_TXAK 0x08 +#define I2CR_MTX 0x10 +#define I2CR_MSTA 0x20 +#define I2CR_IIEN 0x40 +#define I2CR_IEN 0x80 +#define IBIC_BIIE 0x80 /* Bus idle interrupt enable */ + +/* register bits different operating codes definition: + * 1) I2SR: Interrupt flags clear operation differ between SoCs: + * - write zero to clear(w0c) INT flag on i.MX, + * - but write one to clear(w1c) INT flag on Vybrid. + * 2) I2CR: I2C module enable operation also differ between SoCs: + * - set I2CR_IEN bit enable the module on i.MX, + * - but clear I2CR_IEN bit enable the module on Vybrid. + */ +#define I2SR_CLR_OPCODE_W0C 0x0 +#define I2SR_CLR_OPCODE_W1C (I2SR_IAL | I2SR_IIF) +#define I2CR_IEN_OPCODE_0 0x0 +#define I2CR_IEN_OPCODE_1 I2CR_IEN + +#define I2C_PM_TIMEOUT 10 /* ms */ + +/* + * sorted list of clock divider, register value pairs + * taken from table 26-5, p.26-9, Freescale i.MX + * Integrated Portable System Processor Reference Manual + * Document Number: MC9328MXLRM, Rev. 5.1, 06/2007 + * + * Duplicated divider values removed from list + */ +struct imx_i2c_clk_pair { + u16 div; + u16 val; +}; + +static struct imx_i2c_clk_pair imx_i2c_clk_div[] = { + { 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 }, + { 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 }, + { 42, 0x03 }, { 44, 0x27 }, { 48, 0x28 }, { 52, 0x05 }, + { 56, 0x29 }, { 60, 0x06 }, { 64, 0x2A }, { 72, 0x2B }, + { 80, 0x2C }, { 88, 0x09 }, { 96, 0x2D }, { 104, 0x0A }, + { 112, 0x2E }, { 128, 0x2F }, { 144, 0x0C }, { 160, 0x30 }, + { 192, 0x31 }, { 224, 0x32 }, { 240, 0x0F }, { 256, 0x33 }, + { 288, 0x10 }, { 320, 0x34 }, { 384, 0x35 }, { 448, 0x36 }, + { 480, 0x13 }, { 512, 0x37 }, { 576, 0x14 }, { 640, 0x38 }, + { 768, 0x39 }, { 896, 0x3A }, { 960, 0x17 }, { 1024, 0x3B }, + { 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E }, + { 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D }, + { 3072, 0x1E }, { 3840, 0x1F } +}; + +/* Vybrid VF610 clock divider, register value pairs */ +static struct imx_i2c_clk_pair vf610_i2c_clk_div[] = { + { 20, 0x00 }, { 22, 0x01 }, { 24, 0x02 }, { 26, 0x03 }, + { 28, 0x04 }, { 30, 0x05 }, { 32, 0x09 }, { 34, 0x06 }, + { 36, 0x0A }, { 40, 0x07 }, { 44, 0x0C }, { 48, 0x0D }, + { 52, 0x43 }, { 56, 0x0E }, { 60, 0x45 }, { 64, 0x12 }, + { 68, 0x0F }, { 72, 0x13 }, { 80, 0x14 }, { 88, 0x15 }, + { 96, 0x19 }, { 104, 0x16 }, { 112, 0x1A }, { 128, 0x17 }, + { 136, 0x4F }, { 144, 0x1C }, { 160, 0x1D }, { 176, 0x55 }, + { 192, 0x1E }, { 208, 0x56 }, { 224, 0x22 }, { 228, 0x24 }, + { 240, 0x1F }, { 256, 0x23 }, { 288, 0x5C }, { 320, 0x25 }, + { 384, 0x26 }, { 448, 0x2A }, { 480, 0x27 }, { 512, 0x2B }, + { 576, 0x2C }, { 640, 0x2D }, { 768, 0x31 }, { 896, 0x32 }, + { 960, 0x2F }, { 1024, 0x33 }, { 1152, 0x34 }, { 1280, 0x35 }, + { 1536, 0x36 }, { 1792, 0x3A }, { 1920, 0x37 }, { 2048, 0x3B }, + { 2304, 0x3C }, { 2560, 0x3D }, { 3072, 0x3E }, { 3584, 0x7A }, + { 3840, 0x3F }, { 4096, 0x7B }, { 5120, 0x7D }, { 6144, 0x7E }, +}; + +enum imx_i2c_type { + IMX1_I2C, + IMX21_I2C, + VF610_I2C, +}; + +struct imx_i2c_hwdata { + enum imx_i2c_type devtype; + unsigned int regshift; + struct imx_i2c_clk_pair *clk_div; + unsigned int ndivs; + unsigned int i2sr_clr_opcode; + unsigned int i2cr_ien_opcode; + /* + * Errata ERR007805 or e7805: + * I2C: When the I2C clock speed is configured for 400 kHz, + * the SCL low period violates the I2C spec of 1.3 uS min. + */ + bool has_err007805; +}; + +struct imx_i2c_dma { + struct dma_chan *chan_tx; + struct dma_chan *chan_rx; + struct dma_chan *chan_using; + struct completion cmd_complete; + dma_addr_t dma_buf; + unsigned int dma_len; + enum dma_transfer_direction dma_transfer_dir; + enum dma_data_direction dma_data_dir; +}; + +struct imx_i2c_struct { + struct i2c_adapter adapter; + struct clk *clk; + struct notifier_block clk_change_nb; + void __iomem *base; + wait_queue_head_t queue; + unsigned long i2csr; + unsigned int disable_delay; + int stopped; + unsigned int ifdr; /* IMX_I2C_IFDR */ + unsigned int cur_clk; + unsigned int bitrate; + const struct imx_i2c_hwdata *hwdata; + struct i2c_bus_recovery_info rinfo; + + struct pinctrl *pinctrl; + struct pinctrl_state *pinctrl_pins_default; + struct pinctrl_state *pinctrl_pins_gpio; + + struct imx_i2c_dma *dma; + struct i2c_client *slave; + enum i2c_slave_event last_slave_event; + + /* For checking slave events. */ + spinlock_t slave_lock; + struct hrtimer slave_timer; +}; + +static const struct imx_i2c_hwdata imx1_i2c_hwdata = { + .devtype = IMX1_I2C, + .regshift = IMX_I2C_REGSHIFT, + .clk_div = imx_i2c_clk_div, + .ndivs = ARRAY_SIZE(imx_i2c_clk_div), + .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C, + .i2cr_ien_opcode = I2CR_IEN_OPCODE_1, + +}; + +static const struct imx_i2c_hwdata imx21_i2c_hwdata = { + .devtype = IMX21_I2C, + .regshift = IMX_I2C_REGSHIFT, + .clk_div = imx_i2c_clk_div, + .ndivs = ARRAY_SIZE(imx_i2c_clk_div), + .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C, + .i2cr_ien_opcode = I2CR_IEN_OPCODE_1, + +}; + +static const struct imx_i2c_hwdata imx6_i2c_hwdata = { + .devtype = IMX21_I2C, + .regshift = IMX_I2C_REGSHIFT, + .clk_div = imx_i2c_clk_div, + .ndivs = ARRAY_SIZE(imx_i2c_clk_div), + .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C, + .i2cr_ien_opcode = I2CR_IEN_OPCODE_1, + .has_err007805 = true, +}; + +static struct imx_i2c_hwdata vf610_i2c_hwdata = { + .devtype = VF610_I2C, + .regshift = VF610_I2C_REGSHIFT, + .clk_div = vf610_i2c_clk_div, + .ndivs = ARRAY_SIZE(vf610_i2c_clk_div), + .i2sr_clr_opcode = I2SR_CLR_OPCODE_W1C, + .i2cr_ien_opcode = I2CR_IEN_OPCODE_0, + +}; + +static const struct platform_device_id imx_i2c_devtype[] = { + { + .name = "imx1-i2c", + .driver_data = (kernel_ulong_t)&imx1_i2c_hwdata, + }, { + .name = "imx21-i2c", + .driver_data = (kernel_ulong_t)&imx21_i2c_hwdata, + }, { + /* sentinel */ + } +}; +MODULE_DEVICE_TABLE(platform, imx_i2c_devtype); + +static const struct of_device_id i2c_imx_dt_ids[] = { + { .compatible = "fsl,imx1-i2c", .data = &imx1_i2c_hwdata, }, + { .compatible = "fsl,imx21-i2c", .data = &imx21_i2c_hwdata, }, + { .compatible = "fsl,imx6q-i2c", .data = &imx6_i2c_hwdata, }, + { .compatible = "fsl,imx6sl-i2c", .data = &imx6_i2c_hwdata, }, + { .compatible = "fsl,imx6sll-i2c", .data = &imx6_i2c_hwdata, }, + { .compatible = "fsl,imx6sx-i2c", .data = &imx6_i2c_hwdata, }, + { .compatible = "fsl,imx6ul-i2c", .data = &imx6_i2c_hwdata, }, + { .compatible = "fsl,imx7s-i2c", .data = &imx6_i2c_hwdata, }, + { .compatible = "fsl,imx8mm-i2c", .data = &imx6_i2c_hwdata, }, + { .compatible = "fsl,imx8mn-i2c", .data = &imx6_i2c_hwdata, }, + { .compatible = "fsl,imx8mp-i2c", .data = &imx6_i2c_hwdata, }, + { .compatible = "fsl,imx8mq-i2c", .data = &imx6_i2c_hwdata, }, + { .compatible = "fsl,vf610-i2c", .data = &vf610_i2c_hwdata, }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, i2c_imx_dt_ids); + +static const struct acpi_device_id i2c_imx_acpi_ids[] = { + {"NXP0001", .driver_data = (kernel_ulong_t)&vf610_i2c_hwdata}, + { } +}; +MODULE_DEVICE_TABLE(acpi, i2c_imx_acpi_ids); + +static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx) +{ + return i2c_imx->hwdata->devtype == IMX1_I2C; +} + +static inline int is_vf610_i2c(struct imx_i2c_struct *i2c_imx) +{ + return i2c_imx->hwdata->devtype == VF610_I2C; +} + +static inline void imx_i2c_write_reg(unsigned int val, + struct imx_i2c_struct *i2c_imx, unsigned int reg) +{ + writeb(val, i2c_imx->base + (reg << i2c_imx->hwdata->regshift)); +} + +static inline unsigned char imx_i2c_read_reg(struct imx_i2c_struct *i2c_imx, + unsigned int reg) +{ + return readb(i2c_imx->base + (reg << i2c_imx->hwdata->regshift)); +} + +static void i2c_imx_clear_irq(struct imx_i2c_struct *i2c_imx, unsigned int bits) +{ + unsigned int temp; + + /* + * i2sr_clr_opcode is the value to clear all interrupts. Here we want to + * clear only <bits>, so we write ~i2sr_clr_opcode with just <bits> + * toggled. This is required because i.MX needs W0C and Vybrid uses W1C. + */ + temp = ~i2c_imx->hwdata->i2sr_clr_opcode ^ bits; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); +} + +/* Set up i2c controller register and i2c status register to default value. */ +static void i2c_imx_reset_regs(struct imx_i2c_struct *i2c_imx) +{ + imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN, + i2c_imx, IMX_I2C_I2CR); + i2c_imx_clear_irq(i2c_imx, I2SR_IIF | I2SR_IAL); +} + +/* Functions for DMA support */ +static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx, + dma_addr_t phy_addr) +{ + struct imx_i2c_dma *dma; + struct dma_slave_config dma_sconfig; + struct device *dev = &i2c_imx->adapter.dev; + int ret; + + dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL); + if (!dma) + return; + + dma->chan_tx = dma_request_chan(dev, "tx"); + if (IS_ERR(dma->chan_tx)) { + ret = PTR_ERR(dma->chan_tx); + if (ret != -ENODEV && ret != -EPROBE_DEFER) + dev_err(dev, "can't request DMA tx channel (%d)\n", ret); + goto fail_al; + } + + dma_sconfig.dst_addr = phy_addr + + (IMX_I2C_I2DR << i2c_imx->hwdata->regshift); + dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + dma_sconfig.dst_maxburst = 1; + dma_sconfig.direction = DMA_MEM_TO_DEV; + ret = dmaengine_slave_config(dma->chan_tx, &dma_sconfig); + if (ret < 0) { + dev_err(dev, "can't configure tx channel (%d)\n", ret); + goto fail_tx; + } + + dma->chan_rx = dma_request_chan(dev, "rx"); + if (IS_ERR(dma->chan_rx)) { + ret = PTR_ERR(dma->chan_rx); + if (ret != -ENODEV && ret != -EPROBE_DEFER) + dev_err(dev, "can't request DMA rx channel (%d)\n", ret); + goto fail_tx; + } + + dma_sconfig.src_addr = phy_addr + + (IMX_I2C_I2DR << i2c_imx->hwdata->regshift); + dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + dma_sconfig.src_maxburst = 1; + dma_sconfig.direction = DMA_DEV_TO_MEM; + ret = dmaengine_slave_config(dma->chan_rx, &dma_sconfig); + if (ret < 0) { + dev_err(dev, "can't configure rx channel (%d)\n", ret); + goto fail_rx; + } + + i2c_imx->dma = dma; + init_completion(&dma->cmd_complete); + dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n", + dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx)); + + return; + +fail_rx: + dma_release_channel(dma->chan_rx); +fail_tx: + dma_release_channel(dma->chan_tx); +fail_al: + devm_kfree(dev, dma); +} + +static void i2c_imx_dma_callback(void *arg) +{ + struct imx_i2c_struct *i2c_imx = (struct imx_i2c_struct *)arg; + struct imx_i2c_dma *dma = i2c_imx->dma; + + dma_unmap_single(dma->chan_using->device->dev, dma->dma_buf, + dma->dma_len, dma->dma_data_dir); + complete(&dma->cmd_complete); +} + +static int i2c_imx_dma_xfer(struct imx_i2c_struct *i2c_imx, + struct i2c_msg *msgs) +{ + struct imx_i2c_dma *dma = i2c_imx->dma; + struct dma_async_tx_descriptor *txdesc; + struct device *dev = &i2c_imx->adapter.dev; + struct device *chan_dev = dma->chan_using->device->dev; + + dma->dma_buf = dma_map_single(chan_dev, msgs->buf, + dma->dma_len, dma->dma_data_dir); + if (dma_mapping_error(chan_dev, dma->dma_buf)) { + dev_err(dev, "DMA mapping failed\n"); + goto err_map; + } + + txdesc = dmaengine_prep_slave_single(dma->chan_using, dma->dma_buf, + dma->dma_len, dma->dma_transfer_dir, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!txdesc) { + dev_err(dev, "Not able to get desc for DMA xfer\n"); + goto err_desc; + } + + reinit_completion(&dma->cmd_complete); + txdesc->callback = i2c_imx_dma_callback; + txdesc->callback_param = i2c_imx; + if (dma_submit_error(dmaengine_submit(txdesc))) { + dev_err(dev, "DMA submit failed\n"); + goto err_submit; + } + + dma_async_issue_pending(dma->chan_using); + return 0; + +err_submit: + dmaengine_terminate_sync(dma->chan_using); +err_desc: + dma_unmap_single(chan_dev, dma->dma_buf, + dma->dma_len, dma->dma_data_dir); +err_map: + return -EINVAL; +} + +static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx) +{ + struct imx_i2c_dma *dma = i2c_imx->dma; + + dma->dma_buf = 0; + dma->dma_len = 0; + + dma_release_channel(dma->chan_tx); + dma->chan_tx = NULL; + + dma_release_channel(dma->chan_rx); + dma->chan_rx = NULL; + + dma->chan_using = NULL; +} + +static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool atomic) +{ + unsigned long orig_jiffies = jiffies; + unsigned int temp; + + while (1) { + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); + + /* check for arbitration lost */ + if (temp & I2SR_IAL) { + i2c_imx_clear_irq(i2c_imx, I2SR_IAL); + return -EAGAIN; + } + + if (for_busy && (temp & I2SR_IBB)) { + i2c_imx->stopped = 0; + break; + } + if (!for_busy && !(temp & I2SR_IBB)) { + i2c_imx->stopped = 1; + break; + } + if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) { + dev_dbg(&i2c_imx->adapter.dev, + "<%s> I2C bus is busy\n", __func__); + return -ETIMEDOUT; + } + if (atomic) + udelay(100); + else + schedule(); + } + + return 0; +} + +static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx, bool atomic) +{ + if (atomic) { + void __iomem *addr = i2c_imx->base + (IMX_I2C_I2SR << i2c_imx->hwdata->regshift); + unsigned int regval; + + /* + * The formula for the poll timeout is documented in the RM + * Rev.5 on page 1878: + * T_min = 10/F_scl + * Set the value hard as it is done for the non-atomic use-case. + * Use 10 kHz for the calculation since this is the minimum + * allowed SMBus frequency. Also add an offset of 100us since it + * turned out that the I2SR_IIF bit isn't set correctly within + * the minimum timeout in polling mode. + */ + readb_poll_timeout_atomic(addr, regval, regval & I2SR_IIF, 5, 1000 + 100); + i2c_imx->i2csr = regval; + i2c_imx_clear_irq(i2c_imx, I2SR_IIF | I2SR_IAL); + } else { + wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10); + } + + if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) { + dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__); + return -ETIMEDOUT; + } + + /* check for arbitration lost */ + if (i2c_imx->i2csr & I2SR_IAL) { + dev_dbg(&i2c_imx->adapter.dev, "<%s> Arbitration lost\n", __func__); + i2c_imx_clear_irq(i2c_imx, I2SR_IAL); + + i2c_imx->i2csr = 0; + return -EAGAIN; + } + + dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__); + i2c_imx->i2csr = 0; + return 0; +} + +static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx) +{ + if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) { + dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__); + return -ENXIO; /* No ACK */ + } + + dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__); + return 0; +} + +static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx, + unsigned int i2c_clk_rate) +{ + struct imx_i2c_clk_pair *i2c_clk_div = i2c_imx->hwdata->clk_div; + unsigned int div; + int i; + + if (i2c_imx->hwdata->has_err007805 && i2c_imx->bitrate > 384000) { + dev_dbg(&i2c_imx->adapter.dev, + "SoC errata ERR007805 or e7805 applies, bus frequency limited from %d Hz to 384000 Hz.\n", + i2c_imx->bitrate); + i2c_imx->bitrate = 384000; + } + + /* Divider value calculation */ + if (i2c_imx->cur_clk == i2c_clk_rate) + return; + + i2c_imx->cur_clk = i2c_clk_rate; + + div = DIV_ROUND_UP(i2c_clk_rate, i2c_imx->bitrate); + if (div < i2c_clk_div[0].div) + i = 0; + else if (div > i2c_clk_div[i2c_imx->hwdata->ndivs - 1].div) + i = i2c_imx->hwdata->ndivs - 1; + else + for (i = 0; i2c_clk_div[i].div < div; i++) + ; + + /* Store divider value */ + i2c_imx->ifdr = i2c_clk_div[i].val; + + /* + * There dummy delay is calculated. + * It should be about one I2C clock period long. + * This delay is used in I2C bus disable function + * to fix chip hardware bug. + */ + i2c_imx->disable_delay = DIV_ROUND_UP(500000U * i2c_clk_div[i].div, + i2c_clk_rate / 2); + +#ifdef CONFIG_I2C_DEBUG_BUS + dev_dbg(&i2c_imx->adapter.dev, "I2C_CLK=%d, REQ DIV=%d\n", + i2c_clk_rate, div); + dev_dbg(&i2c_imx->adapter.dev, "IFDR[IC]=0x%x, REAL DIV=%d\n", + i2c_clk_div[i].val, i2c_clk_div[i].div); +#endif +} + +static int i2c_imx_clk_notifier_call(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct clk_notifier_data *ndata = data; + struct imx_i2c_struct *i2c_imx = container_of(nb, + struct imx_i2c_struct, + clk_change_nb); + + if (action & POST_RATE_CHANGE) + i2c_imx_set_clk(i2c_imx, ndata->new_rate); + + return NOTIFY_OK; +} + +static int i2c_imx_start(struct imx_i2c_struct *i2c_imx, bool atomic) +{ + unsigned int temp = 0; + int result; + + imx_i2c_write_reg(i2c_imx->ifdr, i2c_imx, IMX_I2C_IFDR); + /* Enable I2C controller */ + imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR); + imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode, i2c_imx, IMX_I2C_I2CR); + + /* Wait controller to be stable */ + if (atomic) + udelay(50); + else + usleep_range(50, 150); + + /* Start I2C transaction */ + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp |= I2CR_MSTA; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + result = i2c_imx_bus_busy(i2c_imx, 1, atomic); + if (result) + return result; + + temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK; + if (atomic) + temp &= ~I2CR_IIEN; /* Disable interrupt */ + + temp &= ~I2CR_DMAEN; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + return result; +} + +static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx, bool atomic) +{ + unsigned int temp = 0; + + if (!i2c_imx->stopped) { + /* Stop I2C transaction */ + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + if (!(temp & I2CR_MSTA)) + i2c_imx->stopped = 1; + temp &= ~(I2CR_MSTA | I2CR_MTX); + if (i2c_imx->dma) + temp &= ~I2CR_DMAEN; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + } + if (is_imx1_i2c(i2c_imx)) { + /* + * This delay caused by an i.MXL hardware bug. + * If no (or too short) delay, no "STOP" bit will be generated. + */ + udelay(i2c_imx->disable_delay); + } + + if (!i2c_imx->stopped) + i2c_imx_bus_busy(i2c_imx, 0, atomic); + + /* Disable I2C controller */ + temp = i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN, + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); +} + +/* + * Enable bus idle interrupts + * Note: IBIC register will be cleared after disabled i2c module. + * All of layerscape series SoCs support IBIC register. + */ +static void i2c_imx_enable_bus_idle(struct imx_i2c_struct *i2c_imx) +{ + if (is_vf610_i2c(i2c_imx)) { + unsigned int temp; + + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_IBIC); + temp |= IBIC_BIIE; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_IBIC); + } +} + +static void i2c_imx_slave_event(struct imx_i2c_struct *i2c_imx, + enum i2c_slave_event event, u8 *val) +{ + i2c_slave_event(i2c_imx->slave, event, val); + i2c_imx->last_slave_event = event; +} + +static void i2c_imx_slave_finish_op(struct imx_i2c_struct *i2c_imx) +{ + u8 val = 0; + + while (i2c_imx->last_slave_event != I2C_SLAVE_STOP) { + switch (i2c_imx->last_slave_event) { + case I2C_SLAVE_READ_REQUESTED: + i2c_imx_slave_event(i2c_imx, I2C_SLAVE_READ_PROCESSED, + &val); + break; + + case I2C_SLAVE_WRITE_REQUESTED: + case I2C_SLAVE_READ_PROCESSED: + case I2C_SLAVE_WRITE_RECEIVED: + i2c_imx_slave_event(i2c_imx, I2C_SLAVE_STOP, &val); + break; + + case I2C_SLAVE_STOP: + break; + } + } +} + +/* Returns true if the timer should be restarted, false if not. */ +static irqreturn_t i2c_imx_slave_handle(struct imx_i2c_struct *i2c_imx, + unsigned int status, unsigned int ctl) +{ + u8 value = 0; + + if (status & I2SR_IAL) { /* Arbitration lost */ + i2c_imx_clear_irq(i2c_imx, I2SR_IAL); + if (!(status & I2SR_IAAS)) + return IRQ_HANDLED; + } + + if (!(status & I2SR_IBB)) { + /* No master on the bus, that could mean a stop condition. */ + i2c_imx_slave_finish_op(i2c_imx); + return IRQ_HANDLED; + } + + if (!(status & I2SR_ICF)) + /* Data transfer still in progress, ignore this. */ + goto out; + + if (status & I2SR_IAAS) { /* Addressed as a slave */ + i2c_imx_slave_finish_op(i2c_imx); + if (status & I2SR_SRW) { /* Master wants to read from us*/ + dev_dbg(&i2c_imx->adapter.dev, "read requested"); + i2c_imx_slave_event(i2c_imx, + I2C_SLAVE_READ_REQUESTED, &value); + + /* Slave transmit */ + ctl |= I2CR_MTX; + imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR); + + /* Send data */ + imx_i2c_write_reg(value, i2c_imx, IMX_I2C_I2DR); + } else { /* Master wants to write to us */ + dev_dbg(&i2c_imx->adapter.dev, "write requested"); + i2c_imx_slave_event(i2c_imx, + I2C_SLAVE_WRITE_REQUESTED, &value); + + /* Slave receive */ + ctl &= ~I2CR_MTX; + imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR); + /* Dummy read */ + imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); + } + } else if (!(ctl & I2CR_MTX)) { /* Receive mode */ + value = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); + i2c_imx_slave_event(i2c_imx, + I2C_SLAVE_WRITE_RECEIVED, &value); + } else if (!(status & I2SR_RXAK)) { /* Transmit mode received ACK */ + ctl |= I2CR_MTX; + imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR); + + i2c_imx_slave_event(i2c_imx, + I2C_SLAVE_READ_PROCESSED, &value); + + imx_i2c_write_reg(value, i2c_imx, IMX_I2C_I2DR); + } else { /* Transmit mode received NAK, operation is done */ + ctl &= ~I2CR_MTX; + imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR); + imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); + i2c_imx_slave_finish_op(i2c_imx); + return IRQ_HANDLED; + } + +out: + /* + * No need to check the return value here. If it returns 0 or + * 1, then everything is fine. If it returns -1, then the + * timer is running in the handler. This will still work, + * though it may be redone (or already have been done) by the + * timer function. + */ + hrtimer_try_to_cancel(&i2c_imx->slave_timer); + hrtimer_forward_now(&i2c_imx->slave_timer, I2C_IMX_CHECK_DELAY); + hrtimer_restart(&i2c_imx->slave_timer); + return IRQ_HANDLED; +} + +static enum hrtimer_restart i2c_imx_slave_timeout(struct hrtimer *t) +{ + struct imx_i2c_struct *i2c_imx = container_of(t, struct imx_i2c_struct, + slave_timer); + unsigned int ctl, status; + unsigned long flags; + + spin_lock_irqsave(&i2c_imx->slave_lock, flags); + status = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); + ctl = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + i2c_imx_slave_handle(i2c_imx, status, ctl); + spin_unlock_irqrestore(&i2c_imx->slave_lock, flags); + return HRTIMER_NORESTART; +} + +static void i2c_imx_slave_init(struct imx_i2c_struct *i2c_imx) +{ + int temp; + + /* Set slave addr. */ + imx_i2c_write_reg((i2c_imx->slave->addr << 1), i2c_imx, IMX_I2C_IADR); + + i2c_imx_reset_regs(i2c_imx); + + /* Enable module */ + temp = i2c_imx->hwdata->i2cr_ien_opcode; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + + /* Enable interrupt from i2c module */ + temp |= I2CR_IIEN; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + + i2c_imx_enable_bus_idle(i2c_imx); +} + +static int i2c_imx_reg_slave(struct i2c_client *client) +{ + struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(client->adapter); + int ret; + + if (i2c_imx->slave) + return -EBUSY; + + i2c_imx->slave = client; + i2c_imx->last_slave_event = I2C_SLAVE_STOP; + + /* Resume */ + ret = pm_runtime_resume_and_get(i2c_imx->adapter.dev.parent); + if (ret < 0) { + dev_err(&i2c_imx->adapter.dev, "failed to resume i2c controller"); + return ret; + } + + i2c_imx_slave_init(i2c_imx); + + return 0; +} + +static int i2c_imx_unreg_slave(struct i2c_client *client) +{ + struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(client->adapter); + int ret; + + if (!i2c_imx->slave) + return -EINVAL; + + /* Reset slave address. */ + imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR); + + i2c_imx_reset_regs(i2c_imx); + + i2c_imx->slave = NULL; + + /* Suspend */ + ret = pm_runtime_put_sync(i2c_imx->adapter.dev.parent); + if (ret < 0) + dev_err(&i2c_imx->adapter.dev, "failed to suspend i2c controller"); + + return ret; +} + +static irqreturn_t i2c_imx_master_isr(struct imx_i2c_struct *i2c_imx, unsigned int status) +{ + /* save status register */ + i2c_imx->i2csr = status; + wake_up(&i2c_imx->queue); + + return IRQ_HANDLED; +} + +static irqreturn_t i2c_imx_isr(int irq, void *dev_id) +{ + struct imx_i2c_struct *i2c_imx = dev_id; + unsigned int ctl, status; + unsigned long flags; + + spin_lock_irqsave(&i2c_imx->slave_lock, flags); + status = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); + ctl = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + + if (status & I2SR_IIF) { + i2c_imx_clear_irq(i2c_imx, I2SR_IIF); + if (i2c_imx->slave) { + if (!(ctl & I2CR_MSTA)) { + irqreturn_t ret; + + ret = i2c_imx_slave_handle(i2c_imx, + status, ctl); + spin_unlock_irqrestore(&i2c_imx->slave_lock, + flags); + return ret; + } + i2c_imx_slave_finish_op(i2c_imx); + } + spin_unlock_irqrestore(&i2c_imx->slave_lock, flags); + return i2c_imx_master_isr(i2c_imx, status); + } + spin_unlock_irqrestore(&i2c_imx->slave_lock, flags); + + return IRQ_NONE; +} + +static int i2c_imx_dma_write(struct imx_i2c_struct *i2c_imx, + struct i2c_msg *msgs) +{ + int result; + unsigned long time_left; + unsigned int temp = 0; + unsigned long orig_jiffies = jiffies; + struct imx_i2c_dma *dma = i2c_imx->dma; + struct device *dev = &i2c_imx->adapter.dev; + + dma->chan_using = dma->chan_tx; + dma->dma_transfer_dir = DMA_MEM_TO_DEV; + dma->dma_data_dir = DMA_TO_DEVICE; + dma->dma_len = msgs->len - 1; + result = i2c_imx_dma_xfer(i2c_imx, msgs); + if (result) + return result; + + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp |= I2CR_DMAEN; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + + /* + * Write slave address. + * The first byte must be transmitted by the CPU. + */ + imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR); + time_left = wait_for_completion_timeout( + &i2c_imx->dma->cmd_complete, + msecs_to_jiffies(DMA_TIMEOUT)); + if (time_left == 0) { + dmaengine_terminate_sync(dma->chan_using); + return -ETIMEDOUT; + } + + /* Waiting for transfer complete. */ + while (1) { + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); + if (temp & I2SR_ICF) + break; + if (time_after(jiffies, orig_jiffies + + msecs_to_jiffies(DMA_TIMEOUT))) { + dev_dbg(dev, "<%s> Timeout\n", __func__); + return -ETIMEDOUT; + } + schedule(); + } + + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp &= ~I2CR_DMAEN; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + + /* The last data byte must be transferred by the CPU. */ + imx_i2c_write_reg(msgs->buf[msgs->len-1], + i2c_imx, IMX_I2C_I2DR); + result = i2c_imx_trx_complete(i2c_imx, false); + if (result) + return result; + + return i2c_imx_acked(i2c_imx); +} + +static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx, + struct i2c_msg *msgs, bool is_lastmsg) +{ + int result; + unsigned long time_left; + unsigned int temp; + unsigned long orig_jiffies = jiffies; + struct imx_i2c_dma *dma = i2c_imx->dma; + struct device *dev = &i2c_imx->adapter.dev; + + + dma->chan_using = dma->chan_rx; + dma->dma_transfer_dir = DMA_DEV_TO_MEM; + dma->dma_data_dir = DMA_FROM_DEVICE; + /* The last two data bytes must be transferred by the CPU. */ + dma->dma_len = msgs->len - 2; + result = i2c_imx_dma_xfer(i2c_imx, msgs); + if (result) + return result; + + time_left = wait_for_completion_timeout( + &i2c_imx->dma->cmd_complete, + msecs_to_jiffies(DMA_TIMEOUT)); + if (time_left == 0) { + dmaengine_terminate_sync(dma->chan_using); + return -ETIMEDOUT; + } + + /* waiting for transfer complete. */ + while (1) { + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); + if (temp & I2SR_ICF) + break; + if (time_after(jiffies, orig_jiffies + + msecs_to_jiffies(DMA_TIMEOUT))) { + dev_dbg(dev, "<%s> Timeout\n", __func__); + return -ETIMEDOUT; + } + schedule(); + } + + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp &= ~I2CR_DMAEN; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + + /* read n-1 byte data */ + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp |= I2CR_TXAK; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + + msgs->buf[msgs->len-2] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); + /* read n byte data */ + result = i2c_imx_trx_complete(i2c_imx, false); + if (result) + return result; + + if (is_lastmsg) { + /* + * It must generate STOP before read I2DR to prevent + * controller from generating another clock cycle + */ + dev_dbg(dev, "<%s> clear MSTA\n", __func__); + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + if (!(temp & I2CR_MSTA)) + i2c_imx->stopped = 1; + temp &= ~(I2CR_MSTA | I2CR_MTX); + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + if (!i2c_imx->stopped) + i2c_imx_bus_busy(i2c_imx, 0, false); + } else { + /* + * For i2c master receiver repeat restart operation like: + * read -> repeat MSTA -> read/write + * The controller must set MTX before read the last byte in + * the first read operation, otherwise the first read cost + * one extra clock cycle. + */ + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp |= I2CR_MTX; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + } + msgs->buf[msgs->len-1] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); + + return 0; +} + +static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, + bool atomic) +{ + int i, result; + + dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n", + __func__, i2c_8bit_addr_from_msg(msgs)); + + /* write slave address */ + imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR); + result = i2c_imx_trx_complete(i2c_imx, atomic); + if (result) + return result; + result = i2c_imx_acked(i2c_imx); + if (result) + return result; + dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__); + + /* write data */ + for (i = 0; i < msgs->len; i++) { + dev_dbg(&i2c_imx->adapter.dev, + "<%s> write byte: B%d=0x%X\n", + __func__, i, msgs->buf[i]); + imx_i2c_write_reg(msgs->buf[i], i2c_imx, IMX_I2C_I2DR); + result = i2c_imx_trx_complete(i2c_imx, atomic); + if (result) + return result; + result = i2c_imx_acked(i2c_imx); + if (result) + return result; + } + return 0; +} + +static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, + bool is_lastmsg, bool atomic) +{ + int i, result; + unsigned int temp; + int block_data = msgs->flags & I2C_M_RECV_LEN; + int use_dma = i2c_imx->dma && msgs->flags & I2C_M_DMA_SAFE && + msgs->len >= DMA_THRESHOLD && !block_data; + + dev_dbg(&i2c_imx->adapter.dev, + "<%s> write slave address: addr=0x%x\n", + __func__, i2c_8bit_addr_from_msg(msgs)); + + /* write slave address */ + imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR); + result = i2c_imx_trx_complete(i2c_imx, atomic); + if (result) + return result; + result = i2c_imx_acked(i2c_imx); + if (result) + return result; + + dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__); + + /* setup bus to read data */ + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp &= ~I2CR_MTX; + + /* + * Reset the I2CR_TXAK flag initially for SMBus block read since the + * length is unknown + */ + if ((msgs->len - 1) || block_data) + temp &= ~I2CR_TXAK; + if (use_dma) + temp |= I2CR_DMAEN; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */ + + dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__); + + if (use_dma) + return i2c_imx_dma_read(i2c_imx, msgs, is_lastmsg); + + /* read data */ + for (i = 0; i < msgs->len; i++) { + u8 len = 0; + + result = i2c_imx_trx_complete(i2c_imx, atomic); + if (result) + return result; + /* + * First byte is the length of remaining packet + * in the SMBus block data read. Add it to + * msgs->len. + */ + if ((!i) && block_data) { + len = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); + if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX)) + return -EPROTO; + dev_dbg(&i2c_imx->adapter.dev, + "<%s> read length: 0x%X\n", + __func__, len); + msgs->len += len; + } + if (i == (msgs->len - 1)) { + if (is_lastmsg) { + /* + * It must generate STOP before read I2DR to prevent + * controller from generating another clock cycle + */ + dev_dbg(&i2c_imx->adapter.dev, + "<%s> clear MSTA\n", __func__); + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + if (!(temp & I2CR_MSTA)) + i2c_imx->stopped = 1; + temp &= ~(I2CR_MSTA | I2CR_MTX); + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + if (!i2c_imx->stopped) + i2c_imx_bus_busy(i2c_imx, 0, atomic); + } else { + /* + * For i2c master receiver repeat restart operation like: + * read -> repeat MSTA -> read/write + * The controller must set MTX before read the last byte in + * the first read operation, otherwise the first read cost + * one extra clock cycle. + */ + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp |= I2CR_MTX; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + } + } else if (i == (msgs->len - 2)) { + dev_dbg(&i2c_imx->adapter.dev, + "<%s> set TXAK\n", __func__); + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp |= I2CR_TXAK; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + } + if ((!i) && block_data) + msgs->buf[0] = len; + else + msgs->buf[i] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); + dev_dbg(&i2c_imx->adapter.dev, + "<%s> read byte: B%d=0x%X\n", + __func__, i, msgs->buf[i]); + } + return 0; +} + +static int i2c_imx_xfer_common(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num, bool atomic) +{ + unsigned int i, temp; + int result; + bool is_lastmsg = false; + struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter); + + /* Start I2C transfer */ + result = i2c_imx_start(i2c_imx, atomic); + if (result) { + /* + * Bus recovery uses gpiod_get_value_cansleep() which is not + * allowed within atomic context. + */ + if (!atomic && i2c_imx->adapter.bus_recovery_info) { + i2c_recover_bus(&i2c_imx->adapter); + result = i2c_imx_start(i2c_imx, atomic); + } + } + + if (result) + goto fail0; + + /* read/write data */ + for (i = 0; i < num; i++) { + if (i == num - 1) + is_lastmsg = true; + + if (i) { + dev_dbg(&i2c_imx->adapter.dev, + "<%s> repeated start\n", __func__); + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp |= I2CR_RSTA; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + result = i2c_imx_bus_busy(i2c_imx, 1, atomic); + if (result) + goto fail0; + } + dev_dbg(&i2c_imx->adapter.dev, + "<%s> transfer message: %d\n", __func__, i); + /* write/read data */ +#ifdef CONFIG_I2C_DEBUG_BUS + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + dev_dbg(&i2c_imx->adapter.dev, + "<%s> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n", + __func__, + (temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0), + (temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0), + (temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0)); + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); + dev_dbg(&i2c_imx->adapter.dev, + "<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n", + __func__, + (temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0), + (temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0), + (temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0), + (temp & I2SR_RXAK ? 1 : 0)); +#endif + if (msgs[i].flags & I2C_M_RD) { + result = i2c_imx_read(i2c_imx, &msgs[i], is_lastmsg, atomic); + } else { + if (!atomic && + i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD && + msgs[i].flags & I2C_M_DMA_SAFE) + result = i2c_imx_dma_write(i2c_imx, &msgs[i]); + else + result = i2c_imx_write(i2c_imx, &msgs[i], atomic); + } + if (result) + goto fail0; + } + +fail0: + /* Stop I2C transfer */ + i2c_imx_stop(i2c_imx, atomic); + + dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__, + (result < 0) ? "error" : "success msg", + (result < 0) ? result : num); + /* After data is transferred, switch to slave mode(as a receiver) */ + if (i2c_imx->slave) + i2c_imx_slave_init(i2c_imx); + + return (result < 0) ? result : num; +} + +static int i2c_imx_xfer(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num) +{ + struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter); + int result; + + result = pm_runtime_resume_and_get(i2c_imx->adapter.dev.parent); + if (result < 0) + return result; + + result = i2c_imx_xfer_common(adapter, msgs, num, false); + + pm_runtime_mark_last_busy(i2c_imx->adapter.dev.parent); + pm_runtime_put_autosuspend(i2c_imx->adapter.dev.parent); + + return result; +} + +static int i2c_imx_xfer_atomic(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num) +{ + struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter); + int result; + + result = clk_enable(i2c_imx->clk); + if (result) + return result; + + result = i2c_imx_xfer_common(adapter, msgs, num, true); + + clk_disable(i2c_imx->clk); + + return result; +} + +static void i2c_imx_prepare_recovery(struct i2c_adapter *adap) +{ + struct imx_i2c_struct *i2c_imx; + + i2c_imx = container_of(adap, struct imx_i2c_struct, adapter); + + pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_gpio); +} + +static void i2c_imx_unprepare_recovery(struct i2c_adapter *adap) +{ + struct imx_i2c_struct *i2c_imx; + + i2c_imx = container_of(adap, struct imx_i2c_struct, adapter); + + pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_default); +} + +/* + * We switch SCL and SDA to their GPIO function and do some bitbanging + * for bus recovery. These alternative pinmux settings can be + * described in the device tree by a separate pinctrl state "gpio". If + * this is missing this is not a big problem, the only implication is + * that we can't do bus recovery. + */ +static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx, + struct platform_device *pdev) +{ + struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo; + + i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev); + if (!i2c_imx->pinctrl) { + dev_info(&pdev->dev, "pinctrl unavailable, bus recovery not supported\n"); + return 0; + } + if (IS_ERR(i2c_imx->pinctrl)) { + dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n"); + return PTR_ERR(i2c_imx->pinctrl); + } + + i2c_imx->pinctrl_pins_default = pinctrl_lookup_state(i2c_imx->pinctrl, + PINCTRL_STATE_DEFAULT); + i2c_imx->pinctrl_pins_gpio = pinctrl_lookup_state(i2c_imx->pinctrl, + "gpio"); + rinfo->sda_gpiod = devm_gpiod_get(&pdev->dev, "sda", GPIOD_IN); + rinfo->scl_gpiod = devm_gpiod_get(&pdev->dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN); + + if (PTR_ERR(rinfo->sda_gpiod) == -EPROBE_DEFER || + PTR_ERR(rinfo->scl_gpiod) == -EPROBE_DEFER) { + return -EPROBE_DEFER; + } else if (IS_ERR(rinfo->sda_gpiod) || + IS_ERR(rinfo->scl_gpiod) || + IS_ERR(i2c_imx->pinctrl_pins_default) || + IS_ERR(i2c_imx->pinctrl_pins_gpio)) { + dev_dbg(&pdev->dev, "recovery information incomplete\n"); + return 0; + } + + dev_dbg(&pdev->dev, "using scl%s for recovery\n", + rinfo->sda_gpiod ? ",sda" : ""); + + rinfo->prepare_recovery = i2c_imx_prepare_recovery; + rinfo->unprepare_recovery = i2c_imx_unprepare_recovery; + rinfo->recover_bus = i2c_generic_scl_recovery; + i2c_imx->adapter.bus_recovery_info = rinfo; + + return 0; +} + +static u32 i2c_imx_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL + | I2C_FUNC_SMBUS_READ_BLOCK_DATA; +} + +static const struct i2c_algorithm i2c_imx_algo = { + .master_xfer = i2c_imx_xfer, + .master_xfer_atomic = i2c_imx_xfer_atomic, + .functionality = i2c_imx_func, + .reg_slave = i2c_imx_reg_slave, + .unreg_slave = i2c_imx_unreg_slave, +}; + +static int i2c_imx_probe(struct platform_device *pdev) +{ + struct imx_i2c_struct *i2c_imx; + struct resource *res; + struct imxi2c_platform_data *pdata = dev_get_platdata(&pdev->dev); + void __iomem *base; + int irq, ret; + dma_addr_t phy_addr; + const struct imx_i2c_hwdata *match; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(base)) + return PTR_ERR(base); + + phy_addr = (dma_addr_t)res->start; + i2c_imx = devm_kzalloc(&pdev->dev, sizeof(*i2c_imx), GFP_KERNEL); + if (!i2c_imx) + return -ENOMEM; + + spin_lock_init(&i2c_imx->slave_lock); + hrtimer_init(&i2c_imx->slave_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); + i2c_imx->slave_timer.function = i2c_imx_slave_timeout; + + match = device_get_match_data(&pdev->dev); + if (match) + i2c_imx->hwdata = match; + else + i2c_imx->hwdata = (struct imx_i2c_hwdata *) + platform_get_device_id(pdev)->driver_data; + + /* Setup i2c_imx driver structure */ + strscpy(i2c_imx->adapter.name, pdev->name, sizeof(i2c_imx->adapter.name)); + i2c_imx->adapter.owner = THIS_MODULE; + i2c_imx->adapter.algo = &i2c_imx_algo; + i2c_imx->adapter.dev.parent = &pdev->dev; + i2c_imx->adapter.nr = pdev->id; + i2c_imx->adapter.dev.of_node = pdev->dev.of_node; + i2c_imx->base = base; + ACPI_COMPANION_SET(&i2c_imx->adapter.dev, ACPI_COMPANION(&pdev->dev)); + + /* Get I2C clock */ + i2c_imx->clk = devm_clk_get_enabled(&pdev->dev, NULL); + if (IS_ERR(i2c_imx->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(i2c_imx->clk), + "can't get I2C clock\n"); + + /* Init queue */ + init_waitqueue_head(&i2c_imx->queue); + + /* Set up adapter data */ + i2c_set_adapdata(&i2c_imx->adapter, i2c_imx); + + /* Set up platform driver data */ + platform_set_drvdata(pdev, i2c_imx); + + pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + ret = pm_runtime_get_sync(&pdev->dev); + if (ret < 0) + goto rpm_disable; + + /* Request IRQ */ + ret = request_irq(irq, i2c_imx_isr, IRQF_SHARED, pdev->name, i2c_imx); + if (ret) { + dev_err(&pdev->dev, "can't claim irq %d\n", irq); + goto rpm_disable; + } + + /* Set up clock divider */ + i2c_imx->bitrate = I2C_MAX_STANDARD_MODE_FREQ; + ret = of_property_read_u32(pdev->dev.of_node, + "clock-frequency", &i2c_imx->bitrate); + if (ret < 0 && pdata && pdata->bitrate) + i2c_imx->bitrate = pdata->bitrate; + i2c_imx->clk_change_nb.notifier_call = i2c_imx_clk_notifier_call; + clk_notifier_register(i2c_imx->clk, &i2c_imx->clk_change_nb); + i2c_imx_set_clk(i2c_imx, clk_get_rate(i2c_imx->clk)); + + i2c_imx_reset_regs(i2c_imx); + + /* Init optional bus recovery function */ + ret = i2c_imx_init_recovery_info(i2c_imx, pdev); + /* Give it another chance if pinctrl used is not ready yet */ + if (ret == -EPROBE_DEFER) + goto clk_notifier_unregister; + + /* Add I2C adapter */ + ret = i2c_add_numbered_adapter(&i2c_imx->adapter); + if (ret < 0) + goto clk_notifier_unregister; + + pm_runtime_mark_last_busy(&pdev->dev); + pm_runtime_put_autosuspend(&pdev->dev); + + dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", irq); + dev_dbg(&i2c_imx->adapter.dev, "device resources: %pR\n", res); + dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n", + i2c_imx->adapter.name); + dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n"); + + /* Init DMA config if supported */ + i2c_imx_dma_request(i2c_imx, phy_addr); + + return 0; /* Return OK */ + +clk_notifier_unregister: + clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb); + free_irq(irq, i2c_imx); +rpm_disable: + pm_runtime_put_noidle(&pdev->dev); + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_dont_use_autosuspend(&pdev->dev); + return ret; +} + +static void i2c_imx_remove(struct platform_device *pdev) +{ + struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev); + int irq, ret; + + ret = pm_runtime_get_sync(&pdev->dev); + + hrtimer_cancel(&i2c_imx->slave_timer); + + /* remove adapter */ + dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n"); + i2c_del_adapter(&i2c_imx->adapter); + + if (i2c_imx->dma) + i2c_imx_dma_free(i2c_imx); + + if (ret >= 0) { + /* setup chip registers to defaults */ + imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR); + imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IFDR); + imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR); + imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR); + } + + clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb); + irq = platform_get_irq(pdev, 0); + if (irq >= 0) + free_irq(irq, i2c_imx); + + pm_runtime_put_noidle(&pdev->dev); + pm_runtime_disable(&pdev->dev); +} + +static int __maybe_unused i2c_imx_runtime_suspend(struct device *dev) +{ + struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev); + + clk_disable(i2c_imx->clk); + + return 0; +} + +static int __maybe_unused i2c_imx_runtime_resume(struct device *dev) +{ + struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev); + int ret; + + ret = clk_enable(i2c_imx->clk); + if (ret) + dev_err(dev, "can't enable I2C clock, ret=%d\n", ret); + + return ret; +} + +static const struct dev_pm_ops i2c_imx_pm_ops = { + SET_RUNTIME_PM_OPS(i2c_imx_runtime_suspend, + i2c_imx_runtime_resume, NULL) +}; + +static struct platform_driver i2c_imx_driver = { + .probe = i2c_imx_probe, + .remove_new = i2c_imx_remove, + .driver = { + .name = DRIVER_NAME, + .pm = &i2c_imx_pm_ops, + .of_match_table = i2c_imx_dt_ids, + .acpi_match_table = i2c_imx_acpi_ids, + }, + .id_table = imx_i2c_devtype, +}; + +static int __init i2c_adap_imx_init(void) +{ + return platform_driver_register(&i2c_imx_driver); +} +subsys_initcall(i2c_adap_imx_init); + +static void __exit i2c_adap_imx_exit(void) +{ + platform_driver_unregister(&i2c_imx_driver); +} +module_exit(i2c_adap_imx_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Darius Augulis"); +MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus"); +MODULE_ALIAS("platform:" DRIVER_NAME); diff --git a/drivers/i2c/busses/i2c-iop3xx.c b/drivers/i2c/busses/i2c-iop3xx.c new file mode 100644 index 000000000..f2f7ebeea --- /dev/null +++ b/drivers/i2c/busses/i2c-iop3xx.c @@ -0,0 +1,542 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* ------------------------------------------------------------------------- */ +/* i2c-iop3xx.c i2c driver algorithms for Intel XScale IOP3xx & IXP46x */ +/* ------------------------------------------------------------------------- */ +/* Copyright (C) 2003 Peter Milne, D-TACQ Solutions Ltd + * <Peter dot Milne at D hyphen TACQ dot com> + * + * With acknowledgements to i2c-algo-ibm_ocp.c by + * Ian DaSilva, MontaVista Software, Inc. idasilva@mvista.com + * + * And i2c-algo-pcf.c, which was created by Simon G. Vogl and Hans Berglund: + * + * Copyright (C) 1995-1997 Simon G. Vogl, 1998-2000 Hans Berglund + * + * And which acknowledged Kyösti Mälkki <kmalkki@cc.hut.fi>, + * Frodo Looijaard <frodol@dds.nl>, Martin Bailey<mbailey@littlefeet-inc.com> + * + * Major cleanup by Deepak Saxena <dsaxena@plexity.net>, 01/2005: + * + * - Use driver model to pass per-chip info instead of hardcoding and #ifdefs + * - Use ioremap/__raw_readl/__raw_writel instead of direct dereference + * - Make it work with IXP46x chips + * - Cleanup function names, coding style, etc + * + * - writing to slave address causes latchup on iop331. + * fix: driver refuses to address self. + */ + +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/errno.h> +#include <linux/platform_device.h> +#include <linux/i2c.h> +#include <linux/io.h> +#include <linux/gpio/consumer.h> + +#include "i2c-iop3xx.h" + +/* global unit counter */ +static int i2c_id; + +static inline unsigned char +iic_cook_addr(struct i2c_msg *msg) +{ + unsigned char addr; + + addr = i2c_8bit_addr_from_msg(msg); + + return addr; +} + +static void +iop3xx_i2c_reset(struct i2c_algo_iop3xx_data *iop3xx_adap) +{ + /* Follows devman 9.3 */ + __raw_writel(IOP3XX_ICR_UNIT_RESET, iop3xx_adap->ioaddr + CR_OFFSET); + __raw_writel(IOP3XX_ISR_CLEARBITS, iop3xx_adap->ioaddr + SR_OFFSET); + __raw_writel(0, iop3xx_adap->ioaddr + CR_OFFSET); +} + +static void +iop3xx_i2c_enable(struct i2c_algo_iop3xx_data *iop3xx_adap) +{ + u32 cr = IOP3XX_ICR_GCD | IOP3XX_ICR_SCLEN | IOP3XX_ICR_UE; + + /* + * Every time unit enable is asserted, GPOD needs to be cleared + * on IOP3XX to avoid data corruption on the bus. We use the + * gpiod_set_raw_value() to make sure the 0 hits the hardware + * GPOD register. These descriptors are only passed along to + * the device if this is necessary. + */ + if (iop3xx_adap->gpio_scl) + gpiod_set_raw_value(iop3xx_adap->gpio_scl, 0); + if (iop3xx_adap->gpio_sda) + gpiod_set_raw_value(iop3xx_adap->gpio_sda, 0); + + /* NB SR bits not same position as CR IE bits :-( */ + iop3xx_adap->SR_enabled = + IOP3XX_ISR_ALD | IOP3XX_ISR_BERRD | + IOP3XX_ISR_RXFULL | IOP3XX_ISR_TXEMPTY; + + cr |= IOP3XX_ICR_ALD_IE | IOP3XX_ICR_BERR_IE | + IOP3XX_ICR_RXFULL_IE | IOP3XX_ICR_TXEMPTY_IE; + + __raw_writel(cr, iop3xx_adap->ioaddr + CR_OFFSET); +} + +static void +iop3xx_i2c_transaction_cleanup(struct i2c_algo_iop3xx_data *iop3xx_adap) +{ + unsigned long cr = __raw_readl(iop3xx_adap->ioaddr + CR_OFFSET); + + cr &= ~(IOP3XX_ICR_MSTART | IOP3XX_ICR_TBYTE | + IOP3XX_ICR_MSTOP | IOP3XX_ICR_SCLEN); + + __raw_writel(cr, iop3xx_adap->ioaddr + CR_OFFSET); +} + +/* + * NB: the handler has to clear the source of the interrupt! + * Then it passes the SR flags of interest to BH via adap data + */ +static irqreturn_t +iop3xx_i2c_irq_handler(int this_irq, void *dev_id) +{ + struct i2c_algo_iop3xx_data *iop3xx_adap = dev_id; + u32 sr = __raw_readl(iop3xx_adap->ioaddr + SR_OFFSET); + + if ((sr &= iop3xx_adap->SR_enabled)) { + __raw_writel(sr, iop3xx_adap->ioaddr + SR_OFFSET); + iop3xx_adap->SR_received |= sr; + wake_up_interruptible(&iop3xx_adap->waitq); + } + return IRQ_HANDLED; +} + +/* check all error conditions, clear them , report most important */ +static int +iop3xx_i2c_error(u32 sr) +{ + int rc = 0; + + if ((sr & IOP3XX_ISR_BERRD)) { + if (!rc) + rc = -I2C_ERR_BERR; + } + if ((sr & IOP3XX_ISR_ALD)) { + if (!rc) + rc = -I2C_ERR_ALD; + } + return rc; +} + +static inline u32 +iop3xx_i2c_get_srstat(struct i2c_algo_iop3xx_data *iop3xx_adap) +{ + unsigned long flags; + u32 sr; + + spin_lock_irqsave(&iop3xx_adap->lock, flags); + sr = iop3xx_adap->SR_received; + iop3xx_adap->SR_received = 0; + spin_unlock_irqrestore(&iop3xx_adap->lock, flags); + + return sr; +} + +/* + * sleep until interrupted, then recover and analyse the SR + * saved by handler + */ +typedef int (*compare_func)(unsigned test, unsigned mask); +/* returns 1 on correct comparison */ + +static int +iop3xx_i2c_wait_event(struct i2c_algo_iop3xx_data *iop3xx_adap, + unsigned flags, unsigned *status, + compare_func compare) +{ + unsigned sr = 0; + int interrupted; + int done; + int rc = 0; + + do { + interrupted = wait_event_interruptible_timeout ( + iop3xx_adap->waitq, + (done = compare(sr = iop3xx_i2c_get_srstat(iop3xx_adap), flags)), + 1 * HZ + ); + if ((rc = iop3xx_i2c_error(sr)) < 0) { + *status = sr; + return rc; + } else if (!interrupted) { + *status = sr; + return -ETIMEDOUT; + } + } while (!done); + + *status = sr; + + return 0; +} + +/* + * Concrete compare_funcs + */ +static int +all_bits_clear(unsigned test, unsigned mask) +{ + return (test & mask) == 0; +} + +static int +any_bits_set(unsigned test, unsigned mask) +{ + return (test & mask) != 0; +} + +static int +iop3xx_i2c_wait_tx_done(struct i2c_algo_iop3xx_data *iop3xx_adap, int *status) +{ + return iop3xx_i2c_wait_event( + iop3xx_adap, + IOP3XX_ISR_TXEMPTY | IOP3XX_ISR_ALD | IOP3XX_ISR_BERRD, + status, any_bits_set); +} + +static int +iop3xx_i2c_wait_rx_done(struct i2c_algo_iop3xx_data *iop3xx_adap, int *status) +{ + return iop3xx_i2c_wait_event( + iop3xx_adap, + IOP3XX_ISR_RXFULL | IOP3XX_ISR_ALD | IOP3XX_ISR_BERRD, + status, any_bits_set); +} + +static int +iop3xx_i2c_wait_idle(struct i2c_algo_iop3xx_data *iop3xx_adap, int *status) +{ + return iop3xx_i2c_wait_event( + iop3xx_adap, IOP3XX_ISR_UNITBUSY, status, all_bits_clear); +} + +static int +iop3xx_i2c_send_target_addr(struct i2c_algo_iop3xx_data *iop3xx_adap, + struct i2c_msg *msg) +{ + unsigned long cr = __raw_readl(iop3xx_adap->ioaddr + CR_OFFSET); + int status; + int rc; + + /* avoid writing to my slave address (hangs on 80331), + * forbidden in Intel developer manual + */ + if (msg->addr == MYSAR) { + return -EBUSY; + } + + __raw_writel(iic_cook_addr(msg), iop3xx_adap->ioaddr + DBR_OFFSET); + + cr &= ~(IOP3XX_ICR_MSTOP | IOP3XX_ICR_NACK); + cr |= IOP3XX_ICR_MSTART | IOP3XX_ICR_TBYTE; + + __raw_writel(cr, iop3xx_adap->ioaddr + CR_OFFSET); + rc = iop3xx_i2c_wait_tx_done(iop3xx_adap, &status); + + return rc; +} + +static int +iop3xx_i2c_write_byte(struct i2c_algo_iop3xx_data *iop3xx_adap, char byte, + int stop) +{ + unsigned long cr = __raw_readl(iop3xx_adap->ioaddr + CR_OFFSET); + int status; + int rc = 0; + + __raw_writel(byte, iop3xx_adap->ioaddr + DBR_OFFSET); + cr &= ~IOP3XX_ICR_MSTART; + if (stop) { + cr |= IOP3XX_ICR_MSTOP; + } else { + cr &= ~IOP3XX_ICR_MSTOP; + } + cr |= IOP3XX_ICR_TBYTE; + __raw_writel(cr, iop3xx_adap->ioaddr + CR_OFFSET); + rc = iop3xx_i2c_wait_tx_done(iop3xx_adap, &status); + + return rc; +} + +static int +iop3xx_i2c_read_byte(struct i2c_algo_iop3xx_data *iop3xx_adap, char *byte, + int stop) +{ + unsigned long cr = __raw_readl(iop3xx_adap->ioaddr + CR_OFFSET); + int status; + int rc = 0; + + cr &= ~IOP3XX_ICR_MSTART; + + if (stop) { + cr |= IOP3XX_ICR_MSTOP | IOP3XX_ICR_NACK; + } else { + cr &= ~(IOP3XX_ICR_MSTOP | IOP3XX_ICR_NACK); + } + cr |= IOP3XX_ICR_TBYTE; + __raw_writel(cr, iop3xx_adap->ioaddr + CR_OFFSET); + + rc = iop3xx_i2c_wait_rx_done(iop3xx_adap, &status); + + *byte = __raw_readl(iop3xx_adap->ioaddr + DBR_OFFSET); + + return rc; +} + +static int +iop3xx_i2c_writebytes(struct i2c_adapter *i2c_adap, const char *buf, int count) +{ + struct i2c_algo_iop3xx_data *iop3xx_adap = i2c_adap->algo_data; + int ii; + int rc = 0; + + for (ii = 0; rc == 0 && ii != count; ++ii) + rc = iop3xx_i2c_write_byte(iop3xx_adap, buf[ii], ii == count-1); + return rc; +} + +static int +iop3xx_i2c_readbytes(struct i2c_adapter *i2c_adap, char *buf, int count) +{ + struct i2c_algo_iop3xx_data *iop3xx_adap = i2c_adap->algo_data; + int ii; + int rc = 0; + + for (ii = 0; rc == 0 && ii != count; ++ii) + rc = iop3xx_i2c_read_byte(iop3xx_adap, &buf[ii], ii == count-1); + + return rc; +} + +/* + * Description: This function implements combined transactions. Combined + * transactions consist of combinations of reading and writing blocks of data. + * FROM THE SAME ADDRESS + * Each transfer (i.e. a read or a write) is separated by a repeated start + * condition. + */ +static int +iop3xx_i2c_handle_msg(struct i2c_adapter *i2c_adap, struct i2c_msg *pmsg) +{ + struct i2c_algo_iop3xx_data *iop3xx_adap = i2c_adap->algo_data; + int rc; + + rc = iop3xx_i2c_send_target_addr(iop3xx_adap, pmsg); + if (rc < 0) { + return rc; + } + + if ((pmsg->flags&I2C_M_RD)) { + return iop3xx_i2c_readbytes(i2c_adap, pmsg->buf, pmsg->len); + } else { + return iop3xx_i2c_writebytes(i2c_adap, pmsg->buf, pmsg->len); + } +} + +/* + * master_xfer() - main read/write entry + */ +static int +iop3xx_i2c_master_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, + int num) +{ + struct i2c_algo_iop3xx_data *iop3xx_adap = i2c_adap->algo_data; + int im = 0; + int ret = 0; + int status; + + iop3xx_i2c_wait_idle(iop3xx_adap, &status); + iop3xx_i2c_reset(iop3xx_adap); + iop3xx_i2c_enable(iop3xx_adap); + + for (im = 0; ret == 0 && im != num; im++) { + ret = iop3xx_i2c_handle_msg(i2c_adap, &msgs[im]); + } + + iop3xx_i2c_transaction_cleanup(iop3xx_adap); + + if (ret) + return ret; + + return im; +} + +static u32 +iop3xx_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm iop3xx_i2c_algo = { + .master_xfer = iop3xx_i2c_master_xfer, + .functionality = iop3xx_i2c_func, +}; + +static void +iop3xx_i2c_remove(struct platform_device *pdev) +{ + struct i2c_adapter *padapter = platform_get_drvdata(pdev); + struct i2c_algo_iop3xx_data *adapter_data = + (struct i2c_algo_iop3xx_data *)padapter->algo_data; + struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + unsigned long cr = __raw_readl(adapter_data->ioaddr + CR_OFFSET); + + /* + * Disable the actual HW unit + */ + cr &= ~(IOP3XX_ICR_ALD_IE | IOP3XX_ICR_BERR_IE | + IOP3XX_ICR_RXFULL_IE | IOP3XX_ICR_TXEMPTY_IE); + __raw_writel(cr, adapter_data->ioaddr + CR_OFFSET); + + iounmap(adapter_data->ioaddr); + release_mem_region(res->start, IOP3XX_I2C_IO_SIZE); + kfree(adapter_data); + kfree(padapter); +} + +static int +iop3xx_i2c_probe(struct platform_device *pdev) +{ + struct resource *res; + int ret, irq; + struct i2c_adapter *new_adapter; + struct i2c_algo_iop3xx_data *adapter_data; + + new_adapter = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL); + if (!new_adapter) { + ret = -ENOMEM; + goto out; + } + + adapter_data = kzalloc(sizeof(struct i2c_algo_iop3xx_data), GFP_KERNEL); + if (!adapter_data) { + ret = -ENOMEM; + goto free_adapter; + } + + adapter_data->gpio_scl = devm_gpiod_get_optional(&pdev->dev, + "scl", + GPIOD_ASIS); + if (IS_ERR(adapter_data->gpio_scl)) { + ret = PTR_ERR(adapter_data->gpio_scl); + goto free_both; + } + adapter_data->gpio_sda = devm_gpiod_get_optional(&pdev->dev, + "sda", + GPIOD_ASIS); + if (IS_ERR(adapter_data->gpio_sda)) { + ret = PTR_ERR(adapter_data->gpio_sda); + goto free_both; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + ret = -ENODEV; + goto free_both; + } + + if (!request_mem_region(res->start, IOP3XX_I2C_IO_SIZE, pdev->name)) { + ret = -EBUSY; + goto free_both; + } + + /* set the adapter enumeration # */ + adapter_data->id = i2c_id++; + + adapter_data->ioaddr = ioremap(res->start, IOP3XX_I2C_IO_SIZE); + if (!adapter_data->ioaddr) { + ret = -ENOMEM; + goto release_region; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + ret = irq; + goto unmap; + } + ret = request_irq(irq, iop3xx_i2c_irq_handler, 0, + pdev->name, adapter_data); + + if (ret) + goto unmap; + + memcpy(new_adapter->name, pdev->name, strlen(pdev->name)); + new_adapter->owner = THIS_MODULE; + new_adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + new_adapter->dev.parent = &pdev->dev; + new_adapter->dev.of_node = pdev->dev.of_node; + new_adapter->nr = pdev->id; + + /* + * Default values...should these come in from board code? + */ + new_adapter->timeout = HZ; + new_adapter->algo = &iop3xx_i2c_algo; + + init_waitqueue_head(&adapter_data->waitq); + spin_lock_init(&adapter_data->lock); + + iop3xx_i2c_reset(adapter_data); + iop3xx_i2c_enable(adapter_data); + + platform_set_drvdata(pdev, new_adapter); + new_adapter->algo_data = adapter_data; + + i2c_add_numbered_adapter(new_adapter); + + return 0; + +unmap: + iounmap(adapter_data->ioaddr); + +release_region: + release_mem_region(res->start, IOP3XX_I2C_IO_SIZE); + +free_both: + kfree(adapter_data); + +free_adapter: + kfree(new_adapter); + +out: + return ret; +} + +static const struct of_device_id i2c_iop3xx_match[] = { + { .compatible = "intel,iop3xx-i2c", }, + { .compatible = "intel,ixp4xx-i2c", }, + {}, +}; +MODULE_DEVICE_TABLE(of, i2c_iop3xx_match); + +static struct platform_driver iop3xx_i2c_driver = { + .probe = iop3xx_i2c_probe, + .remove_new = iop3xx_i2c_remove, + .driver = { + .name = "IOP3xx-I2C", + .of_match_table = i2c_iop3xx_match, + }, +}; + +module_platform_driver(iop3xx_i2c_driver); + +MODULE_AUTHOR("D-TACQ Solutions Ltd <www.d-tacq.com>"); +MODULE_DESCRIPTION("IOP3xx iic algorithm and driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:IOP3xx-I2C"); diff --git a/drivers/i2c/busses/i2c-iop3xx.h b/drivers/i2c/busses/i2c-iop3xx.h new file mode 100644 index 000000000..143548335 --- /dev/null +++ b/drivers/i2c/busses/i2c-iop3xx.h @@ -0,0 +1,99 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* ------------------------------------------------------------------------- */ +/* i2c-iop3xx.h algorithm driver definitions private to i2c-iop3xx.c */ +/* ------------------------------------------------------------------------- */ +/* Copyright (C) 2003 Peter Milne, D-TACQ Solutions Ltd + * <Peter dot Milne at D hyphen TACQ dot com> + + */ +/* ------------------------------------------------------------------------- */ + + +#ifndef I2C_IOP3XX_H +#define I2C_IOP3XX_H 1 + +/* + * iop321 hardware bit definitions + */ +#define IOP3XX_ICR_FAST_MODE 0x8000 /* 1=400kBps, 0=100kBps */ +#define IOP3XX_ICR_UNIT_RESET 0x4000 /* 1=RESET */ +#define IOP3XX_ICR_SAD_IE 0x2000 /* 1=Slave Detect Interrupt Enable */ +#define IOP3XX_ICR_ALD_IE 0x1000 /* 1=Arb Loss Detect Interrupt Enable */ +#define IOP3XX_ICR_SSD_IE 0x0800 /* 1=Slave STOP Detect Interrupt Enable */ +#define IOP3XX_ICR_BERR_IE 0x0400 /* 1=Bus Error Interrupt Enable */ +#define IOP3XX_ICR_RXFULL_IE 0x0200 /* 1=Receive Full Interrupt Enable */ +#define IOP3XX_ICR_TXEMPTY_IE 0x0100 /* 1=Transmit Empty Interrupt Enable */ +#define IOP3XX_ICR_GCD 0x0080 /* 1=General Call Disable */ +/* + * IOP3XX_ICR_GCD: 1 disables response as slave. "This bit must be set + * when sending a master mode general call message from the I2C unit" + */ +#define IOP3XX_ICR_UE 0x0040 /* 1=Unit Enable */ +/* + * "NOTE: To avoid I2C bus integrity problems, + * the user needs to ensure that the GPIO Output Data Register - + * GPOD bits associated with an I2C port are cleared prior to setting + * the enable bit for that I2C serial port. + * The user prepares to enable I2C port 0 and + * I2C port 1 by clearing GPOD bits 7:6 and GPOD bits 5:4, respectively. + */ +#define IOP3XX_ICR_SCLEN 0x0020 /* 1=SCL enable for master mode */ +#define IOP3XX_ICR_MABORT 0x0010 /* 1=Send a STOP with no data + * NB TBYTE must be clear */ +#define IOP3XX_ICR_TBYTE 0x0008 /* 1=Send/Receive a byte. i2c clears */ +#define IOP3XX_ICR_NACK 0x0004 /* 1=reply with NACK */ +#define IOP3XX_ICR_MSTOP 0x0002 /* 1=send a STOP after next data byte */ +#define IOP3XX_ICR_MSTART 0x0001 /* 1=initiate a START */ + + +#define IOP3XX_ISR_BERRD 0x0400 /* 1=BUS ERROR Detected */ +#define IOP3XX_ISR_SAD 0x0200 /* 1=Slave ADdress Detected */ +#define IOP3XX_ISR_GCAD 0x0100 /* 1=General Call Address Detected */ +#define IOP3XX_ISR_RXFULL 0x0080 /* 1=Receive Full */ +#define IOP3XX_ISR_TXEMPTY 0x0040 /* 1=Transmit Empty */ +#define IOP3XX_ISR_ALD 0x0020 /* 1=Arbitration Loss Detected */ +#define IOP3XX_ISR_SSD 0x0010 /* 1=Slave STOP Detected */ +#define IOP3XX_ISR_BBUSY 0x0008 /* 1=Bus BUSY */ +#define IOP3XX_ISR_UNITBUSY 0x0004 /* 1=Unit Busy */ +#define IOP3XX_ISR_NACK 0x0002 /* 1=Unit Rx or Tx a NACK */ +#define IOP3XX_ISR_RXREAD 0x0001 /* 1=READ 0=WRITE (R/W bit of slave addr */ + +#define IOP3XX_ISR_CLEARBITS 0x07f0 + +#define IOP3XX_ISAR_SAMASK 0x007f + +#define IOP3XX_IDBR_MASK 0x00ff + +#define IOP3XX_IBMR_SCL 0x0002 +#define IOP3XX_IBMR_SDA 0x0001 + +#define IOP3XX_GPOD_I2C0 0x00c0 /* clear these bits to enable ch0 */ +#define IOP3XX_GPOD_I2C1 0x0030 /* clear these bits to enable ch1 */ + +#define MYSAR 0 /* default slave address */ + +#define I2C_ERR 321 +#define I2C_ERR_BERR (I2C_ERR+0) +#define I2C_ERR_ALD (I2C_ERR+1) + + +#define CR_OFFSET 0 +#define SR_OFFSET 0x4 +#define SAR_OFFSET 0x8 +#define DBR_OFFSET 0xc +#define CCR_OFFSET 0x10 +#define BMR_OFFSET 0x14 + +#define IOP3XX_I2C_IO_SIZE 0x18 + +struct i2c_algo_iop3xx_data { + void __iomem *ioaddr; + wait_queue_head_t waitq; + spinlock_t lock; + u32 SR_enabled, SR_received; + int id; + struct gpio_desc *gpio_scl; + struct gpio_desc *gpio_sda; +}; + +#endif /* I2C_IOP3XX_H */ diff --git a/drivers/i2c/busses/i2c-isch.c b/drivers/i2c/busses/i2c-isch.c new file mode 100644 index 000000000..1dc1ceaa4 --- /dev/null +++ b/drivers/i2c/busses/i2c-isch.c @@ -0,0 +1,310 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + i2c-isch.c - Linux kernel driver for Intel SCH chipset SMBus + - Based on i2c-piix4.c + Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl> and + Philip Edelbrock <phil@netroedge.com> + - Intel SCH support + Copyright (c) 2007 - 2008 Jacob Jun Pan <jacob.jun.pan@intel.com> + +*/ + +/* + Supports: + Intel SCH chipsets (AF82US15W, AF82US15L, AF82UL11L) + Note: we assume there can only be one device, with one SMBus interface. +*/ + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/stddef.h> +#include <linux/ioport.h> +#include <linux/i2c.h> +#include <linux/io.h> + +/* SCH SMBus address offsets */ +#define SMBHSTCNT (0 + sch_smba) +#define SMBHSTSTS (1 + sch_smba) +#define SMBHSTCLK (2 + sch_smba) +#define SMBHSTADD (4 + sch_smba) /* TSA */ +#define SMBHSTCMD (5 + sch_smba) +#define SMBHSTDAT0 (6 + sch_smba) +#define SMBHSTDAT1 (7 + sch_smba) +#define SMBBLKDAT (0x20 + sch_smba) + +/* Other settings */ +#define MAX_RETRIES 5000 + +/* I2C constants */ +#define SCH_QUICK 0x00 +#define SCH_BYTE 0x01 +#define SCH_BYTE_DATA 0x02 +#define SCH_WORD_DATA 0x03 +#define SCH_BLOCK_DATA 0x05 + +static unsigned short sch_smba; +static struct i2c_adapter sch_adapter; +static int backbone_speed = 33000; /* backbone speed in kHz */ +module_param(backbone_speed, int, S_IRUSR | S_IWUSR); +MODULE_PARM_DESC(backbone_speed, "Backbone speed in kHz, (default = 33000)"); + +/* + * Start the i2c transaction -- the i2c_access will prepare the transaction + * and this function will execute it. + * return 0 for success and others for failure. + */ +static int sch_transaction(void) +{ + int temp; + int result = 0; + int retries = 0; + + dev_dbg(&sch_adapter.dev, "Transaction (pre): CNT=%02x, CMD=%02x, " + "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb(SMBHSTCNT), + inb(SMBHSTCMD), inb(SMBHSTADD), inb(SMBHSTDAT0), + inb(SMBHSTDAT1)); + + /* Make sure the SMBus host is ready to start transmitting */ + temp = inb(SMBHSTSTS) & 0x0f; + if (temp) { + /* Can not be busy since we checked it in sch_access */ + if (temp & 0x01) { + dev_dbg(&sch_adapter.dev, "Completion (%02x). " + "Clear...\n", temp); + } + if (temp & 0x06) { + dev_dbg(&sch_adapter.dev, "SMBus error (%02x). " + "Resetting...\n", temp); + } + outb(temp, SMBHSTSTS); + temp = inb(SMBHSTSTS) & 0x0f; + if (temp) { + dev_err(&sch_adapter.dev, + "SMBus is not ready: (%02x)\n", temp); + return -EAGAIN; + } + } + + /* start the transaction by setting bit 4 */ + outb(inb(SMBHSTCNT) | 0x10, SMBHSTCNT); + + do { + usleep_range(100, 200); + temp = inb(SMBHSTSTS) & 0x0f; + } while ((temp & 0x08) && (retries++ < MAX_RETRIES)); + + /* If the SMBus is still busy, we give up */ + if (retries > MAX_RETRIES) { + dev_err(&sch_adapter.dev, "SMBus Timeout!\n"); + result = -ETIMEDOUT; + } + if (temp & 0x04) { + result = -EIO; + dev_dbg(&sch_adapter.dev, "Bus collision! SMBus may be " + "locked until next hard reset. (sorry!)\n"); + /* Clock stops and slave is stuck in mid-transmission */ + } else if (temp & 0x02) { + result = -EIO; + dev_err(&sch_adapter.dev, "Error: no response!\n"); + } else if (temp & 0x01) { + dev_dbg(&sch_adapter.dev, "Post complete!\n"); + outb(temp, SMBHSTSTS); + temp = inb(SMBHSTSTS) & 0x07; + if (temp & 0x06) { + /* Completion clear failed */ + dev_dbg(&sch_adapter.dev, "Failed reset at end of " + "transaction (%02x), Bus error!\n", temp); + } + } else { + result = -ENXIO; + dev_dbg(&sch_adapter.dev, "No such address.\n"); + } + dev_dbg(&sch_adapter.dev, "Transaction (post): CNT=%02x, CMD=%02x, " + "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb(SMBHSTCNT), + inb(SMBHSTCMD), inb(SMBHSTADD), inb(SMBHSTDAT0), + inb(SMBHSTDAT1)); + return result; +} + +/* + * This is the main access entry for i2c-sch access + * adap is i2c_adapter pointer, addr is the i2c device bus address, read_write + * (0 for read and 1 for write), size is i2c transaction type and data is the + * union of transaction for data to be transferred or data read from bus. + * return 0 for success and others for failure. + */ +static s32 sch_access(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data *data) +{ + int i, len, temp, rc; + + /* Make sure the SMBus host is not busy */ + temp = inb(SMBHSTSTS) & 0x0f; + if (temp & 0x08) { + dev_dbg(&sch_adapter.dev, "SMBus busy (%02x)\n", temp); + return -EAGAIN; + } + temp = inw(SMBHSTCLK); + if (!temp) { + /* + * We can't determine if we have 33 or 25 MHz clock for + * SMBus, so expect 33 MHz and calculate a bus clock of + * 100 kHz. If we actually run at 25 MHz the bus will be + * run ~75 kHz instead which should do no harm. + */ + dev_notice(&sch_adapter.dev, + "Clock divider uninitialized. Setting defaults\n"); + outw(backbone_speed / (4 * 100), SMBHSTCLK); + } + + dev_dbg(&sch_adapter.dev, "access size: %d %s\n", size, + (read_write)?"READ":"WRITE"); + switch (size) { + case I2C_SMBUS_QUICK: + outb((addr << 1) | read_write, SMBHSTADD); + size = SCH_QUICK; + break; + case I2C_SMBUS_BYTE: + outb((addr << 1) | read_write, SMBHSTADD); + if (read_write == I2C_SMBUS_WRITE) + outb(command, SMBHSTCMD); + size = SCH_BYTE; + break; + case I2C_SMBUS_BYTE_DATA: + outb((addr << 1) | read_write, SMBHSTADD); + outb(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) + outb(data->byte, SMBHSTDAT0); + size = SCH_BYTE_DATA; + break; + case I2C_SMBUS_WORD_DATA: + outb((addr << 1) | read_write, SMBHSTADD); + outb(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) { + outb(data->word & 0xff, SMBHSTDAT0); + outb((data->word & 0xff00) >> 8, SMBHSTDAT1); + } + size = SCH_WORD_DATA; + break; + case I2C_SMBUS_BLOCK_DATA: + outb((addr << 1) | read_write, SMBHSTADD); + outb(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) { + len = data->block[0]; + if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) + return -EINVAL; + outb(len, SMBHSTDAT0); + for (i = 1; i <= len; i++) + outb(data->block[i], SMBBLKDAT+i-1); + } + size = SCH_BLOCK_DATA; + break; + default: + dev_warn(&adap->dev, "Unsupported transaction %d\n", size); + return -EOPNOTSUPP; + } + dev_dbg(&sch_adapter.dev, "write size %d to 0x%04x\n", size, SMBHSTCNT); + outb((inb(SMBHSTCNT) & 0xb0) | (size & 0x7), SMBHSTCNT); + + rc = sch_transaction(); + if (rc) /* Error in transaction */ + return rc; + + if ((read_write == I2C_SMBUS_WRITE) || (size == SCH_QUICK)) + return 0; + + switch (size) { + case SCH_BYTE: + case SCH_BYTE_DATA: + data->byte = inb(SMBHSTDAT0); + break; + case SCH_WORD_DATA: + data->word = inb(SMBHSTDAT0) + (inb(SMBHSTDAT1) << 8); + break; + case SCH_BLOCK_DATA: + data->block[0] = inb(SMBHSTDAT0); + if (data->block[0] == 0 || data->block[0] > I2C_SMBUS_BLOCK_MAX) + return -EPROTO; + for (i = 1; i <= data->block[0]; i++) + data->block[i] = inb(SMBBLKDAT+i-1); + break; + } + return 0; +} + +static u32 sch_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_BLOCK_DATA; +} + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = sch_access, + .functionality = sch_func, +}; + +static struct i2c_adapter sch_adapter = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = &smbus_algorithm, +}; + +static int smbus_sch_probe(struct platform_device *dev) +{ + struct resource *res; + int retval; + + res = platform_get_resource(dev, IORESOURCE_IO, 0); + if (!res) + return -EBUSY; + + if (!devm_request_region(&dev->dev, res->start, resource_size(res), + dev->name)) { + dev_err(&dev->dev, "SMBus region 0x%x already in use!\n", + sch_smba); + return -EBUSY; + } + + sch_smba = res->start; + + dev_dbg(&dev->dev, "SMBA = 0x%X\n", sch_smba); + + /* set up the sysfs linkage to our parent device */ + sch_adapter.dev.parent = &dev->dev; + + snprintf(sch_adapter.name, sizeof(sch_adapter.name), + "SMBus SCH adapter at %04x", sch_smba); + + retval = i2c_add_adapter(&sch_adapter); + if (retval) + sch_smba = 0; + + return retval; +} + +static void smbus_sch_remove(struct platform_device *pdev) +{ + if (sch_smba) { + i2c_del_adapter(&sch_adapter); + sch_smba = 0; + } +} + +static struct platform_driver smbus_sch_driver = { + .driver = { + .name = "isch_smbus", + }, + .probe = smbus_sch_probe, + .remove_new = smbus_sch_remove, +}; + +module_platform_driver(smbus_sch_driver); + +MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@intel.com>"); +MODULE_DESCRIPTION("Intel SCH SMBus driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:isch_smbus"); diff --git a/drivers/i2c/busses/i2c-ismt.c b/drivers/i2c/busses/i2c-ismt.c new file mode 100644 index 000000000..c74985d77 --- /dev/null +++ b/drivers/i2c/busses/i2c-ismt.c @@ -0,0 +1,985 @@ +/* + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * Copyright(c) 2012 Intel Corporation. All rights reserved. + * + * GPL LICENSE SUMMARY + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * The full GNU General Public License is included in this distribution + * in the file called LICENSE.GPL. + * + * BSD LICENSE + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/* + * Supports the SMBus Message Transport (SMT) in the Intel Atom Processor + * S12xx Product Family. + * + * Features supported by this driver: + * Hardware PEC yes + * Block buffer yes + * Block process call transaction yes + * Slave mode no + */ + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/stddef.h> +#include <linux/completion.h> +#include <linux/dma-mapping.h> +#include <linux/i2c.h> +#include <linux/acpi.h> +#include <linux/interrupt.h> + +#include <linux/io-64-nonatomic-lo-hi.h> + +/* PCI Address Constants */ +#define SMBBAR 0 + +/* PCI DIDs for the Intel SMBus Message Transport (SMT) Devices */ +#define PCI_DEVICE_ID_INTEL_S1200_SMT0 0x0c59 +#define PCI_DEVICE_ID_INTEL_S1200_SMT1 0x0c5a +#define PCI_DEVICE_ID_INTEL_CDF_SMT 0x18ac +#define PCI_DEVICE_ID_INTEL_DNV_SMT 0x19ac +#define PCI_DEVICE_ID_INTEL_EBG_SMT 0x1bff +#define PCI_DEVICE_ID_INTEL_AVOTON_SMT 0x1f15 + +#define ISMT_DESC_ENTRIES 2 /* number of descriptor entries */ +#define ISMT_MAX_RETRIES 3 /* number of SMBus retries to attempt */ +#define ISMT_LOG_ENTRIES 3 /* number of interrupt cause log entries */ + +/* Hardware Descriptor Constants - Control Field */ +#define ISMT_DESC_CWRL 0x01 /* Command/Write Length */ +#define ISMT_DESC_BLK 0X04 /* Perform Block Transaction */ +#define ISMT_DESC_FAIR 0x08 /* Set fairness flag upon successful arbit. */ +#define ISMT_DESC_PEC 0x10 /* Packet Error Code */ +#define ISMT_DESC_I2C 0x20 /* I2C Enable */ +#define ISMT_DESC_INT 0x40 /* Interrupt */ +#define ISMT_DESC_SOE 0x80 /* Stop On Error */ + +/* Hardware Descriptor Constants - Status Field */ +#define ISMT_DESC_SCS 0x01 /* Success */ +#define ISMT_DESC_DLTO 0x04 /* Data Low Time Out */ +#define ISMT_DESC_NAK 0x08 /* NAK Received */ +#define ISMT_DESC_CRC 0x10 /* CRC Error */ +#define ISMT_DESC_CLTO 0x20 /* Clock Low Time Out */ +#define ISMT_DESC_COL 0x40 /* Collisions */ +#define ISMT_DESC_LPR 0x80 /* Large Packet Received */ + +/* Macros */ +#define ISMT_DESC_ADDR_RW(addr, rw) (((addr) << 1) | (rw)) + +/* iSMT General Register address offsets (SMBBAR + <addr>) */ +#define ISMT_GR_GCTRL 0x000 /* General Control */ +#define ISMT_GR_SMTICL 0x008 /* SMT Interrupt Cause Location */ +#define ISMT_GR_ERRINTMSK 0x010 /* Error Interrupt Mask */ +#define ISMT_GR_ERRAERMSK 0x014 /* Error AER Mask */ +#define ISMT_GR_ERRSTS 0x018 /* Error Status */ +#define ISMT_GR_ERRINFO 0x01c /* Error Information */ + +/* iSMT Master Registers */ +#define ISMT_MSTR_MDBA 0x100 /* Master Descriptor Base Address */ +#define ISMT_MSTR_MCTRL 0x108 /* Master Control */ +#define ISMT_MSTR_MSTS 0x10c /* Master Status */ +#define ISMT_MSTR_MDS 0x110 /* Master Descriptor Size */ +#define ISMT_MSTR_RPOLICY 0x114 /* Retry Policy */ + +/* iSMT Miscellaneous Registers */ +#define ISMT_SPGT 0x300 /* SMBus PHY Global Timing */ + +/* General Control Register (GCTRL) bit definitions */ +#define ISMT_GCTRL_TRST 0x04 /* Target Reset */ +#define ISMT_GCTRL_KILL 0x08 /* Kill */ +#define ISMT_GCTRL_SRST 0x40 /* Soft Reset */ + +/* Master Control Register (MCTRL) bit definitions */ +#define ISMT_MCTRL_SS 0x01 /* Start/Stop */ +#define ISMT_MCTRL_MEIE 0x10 /* Master Error Interrupt Enable */ +#define ISMT_MCTRL_FMHP 0x00ff0000 /* Firmware Master Head Ptr (FMHP) */ + +/* Master Status Register (MSTS) bit definitions */ +#define ISMT_MSTS_HMTP 0xff0000 /* HW Master Tail Pointer (HMTP) */ +#define ISMT_MSTS_MIS 0x20 /* Master Interrupt Status (MIS) */ +#define ISMT_MSTS_MEIS 0x10 /* Master Error Int Status (MEIS) */ +#define ISMT_MSTS_IP 0x01 /* In Progress */ + +/* Master Descriptor Size (MDS) bit definitions */ +#define ISMT_MDS_MASK 0xff /* Master Descriptor Size mask (MDS) */ + +/* SMBus PHY Global Timing Register (SPGT) bit definitions */ +#define ISMT_SPGT_SPD_MASK 0xc0000000 /* SMBus Speed mask */ +#define ISMT_SPGT_SPD_80K 0x00 /* 80 kHz */ +#define ISMT_SPGT_SPD_100K (0x1 << 30) /* 100 kHz */ +#define ISMT_SPGT_SPD_400K (0x2U << 30) /* 400 kHz */ +#define ISMT_SPGT_SPD_1M (0x3U << 30) /* 1 MHz */ + + +/* MSI Control Register (MSICTL) bit definitions */ +#define ISMT_MSICTL_MSIE 0x01 /* MSI Enable */ + +/* iSMT Hardware Descriptor */ +struct ismt_desc { + u8 tgtaddr_rw; /* target address & r/w bit */ + u8 wr_len_cmd; /* write length in bytes or a command */ + u8 rd_len; /* read length */ + u8 control; /* control bits */ + u8 status; /* status bits */ + u8 retry; /* collision retry and retry count */ + u8 rxbytes; /* received bytes */ + u8 txbytes; /* transmitted bytes */ + u32 dptr_low; /* lower 32 bit of the data pointer */ + u32 dptr_high; /* upper 32 bit of the data pointer */ +} __packed; + +struct ismt_priv { + struct i2c_adapter adapter; + void __iomem *smba; /* PCI BAR */ + struct pci_dev *pci_dev; + struct ismt_desc *hw; /* descriptor virt base addr */ + dma_addr_t io_rng_dma; /* descriptor HW base addr */ + u8 head; /* ring buffer head pointer */ + struct completion cmp; /* interrupt completion */ + u8 buffer[I2C_SMBUS_BLOCK_MAX + 16]; /* temp R/W data buffer */ + dma_addr_t log_dma; + u32 *log; +}; + +static const struct pci_device_id ismt_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT0) }, + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT1) }, + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CDF_SMT) }, + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DNV_SMT) }, + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_EBG_SMT) }, + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_AVOTON_SMT) }, + { 0, } +}; + +MODULE_DEVICE_TABLE(pci, ismt_ids); + +/* Bus speed control bits for slow debuggers - refer to the docs for usage */ +static unsigned int bus_speed; +module_param(bus_speed, uint, S_IRUGO); +MODULE_PARM_DESC(bus_speed, "Bus Speed in kHz (0 = BIOS default)"); + +/** + * __ismt_desc_dump() - dump the contents of a specific descriptor + * @dev: the iSMT device + * @desc: the iSMT hardware descriptor + */ +static void __ismt_desc_dump(struct device *dev, const struct ismt_desc *desc) +{ + + dev_dbg(dev, "Descriptor struct: %p\n", desc); + dev_dbg(dev, "\ttgtaddr_rw=0x%02X\n", desc->tgtaddr_rw); + dev_dbg(dev, "\twr_len_cmd=0x%02X\n", desc->wr_len_cmd); + dev_dbg(dev, "\trd_len= 0x%02X\n", desc->rd_len); + dev_dbg(dev, "\tcontrol= 0x%02X\n", desc->control); + dev_dbg(dev, "\tstatus= 0x%02X\n", desc->status); + dev_dbg(dev, "\tretry= 0x%02X\n", desc->retry); + dev_dbg(dev, "\trxbytes= 0x%02X\n", desc->rxbytes); + dev_dbg(dev, "\ttxbytes= 0x%02X\n", desc->txbytes); + dev_dbg(dev, "\tdptr_low= 0x%08X\n", desc->dptr_low); + dev_dbg(dev, "\tdptr_high= 0x%08X\n", desc->dptr_high); +} +/** + * ismt_desc_dump() - dump the contents of a descriptor for debug purposes + * @priv: iSMT private data + */ +static void ismt_desc_dump(struct ismt_priv *priv) +{ + struct device *dev = &priv->pci_dev->dev; + struct ismt_desc *desc = &priv->hw[priv->head]; + + dev_dbg(dev, "Dump of the descriptor struct: 0x%X\n", priv->head); + __ismt_desc_dump(dev, desc); +} + +/** + * ismt_gen_reg_dump() - dump the iSMT General Registers + * @priv: iSMT private data + */ +static void ismt_gen_reg_dump(struct ismt_priv *priv) +{ + struct device *dev = &priv->pci_dev->dev; + + dev_dbg(dev, "Dump of the iSMT General Registers\n"); + dev_dbg(dev, " GCTRL.... : (0x%p)=0x%X\n", + priv->smba + ISMT_GR_GCTRL, + readl(priv->smba + ISMT_GR_GCTRL)); + dev_dbg(dev, " SMTICL... : (0x%p)=0x%016llX\n", + priv->smba + ISMT_GR_SMTICL, + (long long unsigned int)readq(priv->smba + ISMT_GR_SMTICL)); + dev_dbg(dev, " ERRINTMSK : (0x%p)=0x%X\n", + priv->smba + ISMT_GR_ERRINTMSK, + readl(priv->smba + ISMT_GR_ERRINTMSK)); + dev_dbg(dev, " ERRAERMSK : (0x%p)=0x%X\n", + priv->smba + ISMT_GR_ERRAERMSK, + readl(priv->smba + ISMT_GR_ERRAERMSK)); + dev_dbg(dev, " ERRSTS... : (0x%p)=0x%X\n", + priv->smba + ISMT_GR_ERRSTS, + readl(priv->smba + ISMT_GR_ERRSTS)); + dev_dbg(dev, " ERRINFO.. : (0x%p)=0x%X\n", + priv->smba + ISMT_GR_ERRINFO, + readl(priv->smba + ISMT_GR_ERRINFO)); +} + +/** + * ismt_mstr_reg_dump() - dump the iSMT Master Registers + * @priv: iSMT private data + */ +static void ismt_mstr_reg_dump(struct ismt_priv *priv) +{ + struct device *dev = &priv->pci_dev->dev; + + dev_dbg(dev, "Dump of the iSMT Master Registers\n"); + dev_dbg(dev, " MDBA..... : (0x%p)=0x%016llX\n", + priv->smba + ISMT_MSTR_MDBA, + (long long unsigned int)readq(priv->smba + ISMT_MSTR_MDBA)); + dev_dbg(dev, " MCTRL.... : (0x%p)=0x%X\n", + priv->smba + ISMT_MSTR_MCTRL, + readl(priv->smba + ISMT_MSTR_MCTRL)); + dev_dbg(dev, " MSTS..... : (0x%p)=0x%X\n", + priv->smba + ISMT_MSTR_MSTS, + readl(priv->smba + ISMT_MSTR_MSTS)); + dev_dbg(dev, " MDS...... : (0x%p)=0x%X\n", + priv->smba + ISMT_MSTR_MDS, + readl(priv->smba + ISMT_MSTR_MDS)); + dev_dbg(dev, " RPOLICY.. : (0x%p)=0x%X\n", + priv->smba + ISMT_MSTR_RPOLICY, + readl(priv->smba + ISMT_MSTR_RPOLICY)); + dev_dbg(dev, " SPGT..... : (0x%p)=0x%X\n", + priv->smba + ISMT_SPGT, + readl(priv->smba + ISMT_SPGT)); +} + +/** + * ismt_submit_desc() - add a descriptor to the ring + * @priv: iSMT private data + */ +static void ismt_submit_desc(struct ismt_priv *priv) +{ + uint fmhp; + uint val; + + ismt_desc_dump(priv); + ismt_gen_reg_dump(priv); + ismt_mstr_reg_dump(priv); + + /* Set the FMHP (Firmware Master Head Pointer)*/ + fmhp = ((priv->head + 1) % ISMT_DESC_ENTRIES) << 16; + val = readl(priv->smba + ISMT_MSTR_MCTRL); + writel((val & ~ISMT_MCTRL_FMHP) | fmhp, + priv->smba + ISMT_MSTR_MCTRL); + + /* Set the start bit */ + val = readl(priv->smba + ISMT_MSTR_MCTRL); + writel(val | ISMT_MCTRL_SS, + priv->smba + ISMT_MSTR_MCTRL); +} + +/** + * ismt_process_desc() - handle the completion of the descriptor + * @desc: the iSMT hardware descriptor + * @data: data buffer from the upper layer + * @priv: ismt_priv struct holding our dma buffer + * @size: SMBus transaction type + * @read_write: flag to indicate if this is a read or write + */ +static int ismt_process_desc(const struct ismt_desc *desc, + union i2c_smbus_data *data, + struct ismt_priv *priv, int size, + char read_write) +{ + u8 *dma_buffer = PTR_ALIGN(&priv->buffer[0], 16); + + dev_dbg(&priv->pci_dev->dev, "Processing completed descriptor\n"); + __ismt_desc_dump(&priv->pci_dev->dev, desc); + ismt_gen_reg_dump(priv); + ismt_mstr_reg_dump(priv); + + if (desc->status & ISMT_DESC_SCS) { + if (read_write == I2C_SMBUS_WRITE && + size != I2C_SMBUS_PROC_CALL && + size != I2C_SMBUS_BLOCK_PROC_CALL) + return 0; + + switch (size) { + case I2C_SMBUS_BYTE: + case I2C_SMBUS_BYTE_DATA: + data->byte = dma_buffer[0]; + break; + case I2C_SMBUS_WORD_DATA: + case I2C_SMBUS_PROC_CALL: + data->word = dma_buffer[0] | (dma_buffer[1] << 8); + break; + case I2C_SMBUS_BLOCK_DATA: + case I2C_SMBUS_BLOCK_PROC_CALL: + if (desc->rxbytes != dma_buffer[0] + 1) + return -EMSGSIZE; + + memcpy(data->block, dma_buffer, desc->rxbytes); + break; + case I2C_SMBUS_I2C_BLOCK_DATA: + memcpy(&data->block[1], dma_buffer, desc->rxbytes); + data->block[0] = desc->rxbytes; + break; + } + return 0; + } + + if (likely(desc->status & ISMT_DESC_NAK)) + return -ENXIO; + + if (desc->status & ISMT_DESC_CRC) + return -EBADMSG; + + if (desc->status & ISMT_DESC_COL) + return -EAGAIN; + + if (desc->status & ISMT_DESC_LPR) + return -EPROTO; + + if (desc->status & (ISMT_DESC_DLTO | ISMT_DESC_CLTO)) + return -ETIMEDOUT; + + return -EIO; +} + +/** + * ismt_access() - process an SMBus command + * @adap: the i2c host adapter + * @addr: address of the i2c/SMBus target + * @flags: command options + * @read_write: read from or write to device + * @command: the i2c/SMBus command to issue + * @size: SMBus transaction type + * @data: read/write data buffer + */ +static int ismt_access(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, u8 command, + int size, union i2c_smbus_data *data) +{ + int ret; + unsigned long time_left; + dma_addr_t dma_addr = 0; /* address of the data buffer */ + u8 dma_size = 0; + enum dma_data_direction dma_direction = 0; + struct ismt_desc *desc; + struct ismt_priv *priv = i2c_get_adapdata(adap); + struct device *dev = &priv->pci_dev->dev; + u8 *dma_buffer = PTR_ALIGN(&priv->buffer[0], 16); + + desc = &priv->hw[priv->head]; + + /* Initialize the DMA buffer */ + memset(priv->buffer, 0, sizeof(priv->buffer)); + + /* Initialize the descriptor */ + memset(desc, 0, sizeof(struct ismt_desc)); + desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, read_write); + + /* Always clear the log entries */ + memset(priv->log, 0, ISMT_LOG_ENTRIES * sizeof(u32)); + + /* Initialize common control bits */ + if (likely(pci_dev_msi_enabled(priv->pci_dev))) + desc->control = ISMT_DESC_INT | ISMT_DESC_FAIR; + else + desc->control = ISMT_DESC_FAIR; + + if ((flags & I2C_CLIENT_PEC) && (size != I2C_SMBUS_QUICK) + && (size != I2C_SMBUS_I2C_BLOCK_DATA)) + desc->control |= ISMT_DESC_PEC; + + switch (size) { + case I2C_SMBUS_QUICK: + dev_dbg(dev, "I2C_SMBUS_QUICK\n"); + break; + + case I2C_SMBUS_BYTE: + if (read_write == I2C_SMBUS_WRITE) { + /* + * Send Byte + * The command field contains the write data + */ + dev_dbg(dev, "I2C_SMBUS_BYTE: WRITE\n"); + desc->control |= ISMT_DESC_CWRL; + desc->wr_len_cmd = command; + } else { + /* Receive Byte */ + dev_dbg(dev, "I2C_SMBUS_BYTE: READ\n"); + dma_size = 1; + dma_direction = DMA_FROM_DEVICE; + desc->rd_len = 1; + } + break; + + case I2C_SMBUS_BYTE_DATA: + if (read_write == I2C_SMBUS_WRITE) { + /* + * Write Byte + * Command plus 1 data byte + */ + dev_dbg(dev, "I2C_SMBUS_BYTE_DATA: WRITE\n"); + desc->wr_len_cmd = 2; + dma_size = 2; + dma_direction = DMA_TO_DEVICE; + dma_buffer[0] = command; + dma_buffer[1] = data->byte; + } else { + /* Read Byte */ + dev_dbg(dev, "I2C_SMBUS_BYTE_DATA: READ\n"); + desc->control |= ISMT_DESC_CWRL; + desc->wr_len_cmd = command; + desc->rd_len = 1; + dma_size = 1; + dma_direction = DMA_FROM_DEVICE; + } + break; + + case I2C_SMBUS_WORD_DATA: + if (read_write == I2C_SMBUS_WRITE) { + /* Write Word */ + dev_dbg(dev, "I2C_SMBUS_WORD_DATA: WRITE\n"); + desc->wr_len_cmd = 3; + dma_size = 3; + dma_direction = DMA_TO_DEVICE; + dma_buffer[0] = command; + dma_buffer[1] = data->word & 0xff; + dma_buffer[2] = data->word >> 8; + } else { + /* Read Word */ + dev_dbg(dev, "I2C_SMBUS_WORD_DATA: READ\n"); + desc->wr_len_cmd = command; + desc->control |= ISMT_DESC_CWRL; + desc->rd_len = 2; + dma_size = 2; + dma_direction = DMA_FROM_DEVICE; + } + break; + + case I2C_SMBUS_PROC_CALL: + dev_dbg(dev, "I2C_SMBUS_PROC_CALL\n"); + desc->wr_len_cmd = 3; + desc->rd_len = 2; + dma_size = 3; + dma_direction = DMA_BIDIRECTIONAL; + dma_buffer[0] = command; + dma_buffer[1] = data->word & 0xff; + dma_buffer[2] = data->word >> 8; + break; + + case I2C_SMBUS_BLOCK_DATA: + if (read_write == I2C_SMBUS_WRITE) { + /* Block Write */ + dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA: WRITE\n"); + if (data->block[0] < 1 || data->block[0] > I2C_SMBUS_BLOCK_MAX) + return -EINVAL; + + dma_size = data->block[0] + 1; + dma_direction = DMA_TO_DEVICE; + desc->wr_len_cmd = dma_size; + desc->control |= ISMT_DESC_BLK; + dma_buffer[0] = command; + memcpy(&dma_buffer[1], &data->block[1], dma_size - 1); + } else { + /* Block Read */ + dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA: READ\n"); + dma_size = I2C_SMBUS_BLOCK_MAX; + dma_direction = DMA_FROM_DEVICE; + desc->rd_len = dma_size; + desc->wr_len_cmd = command; + desc->control |= (ISMT_DESC_BLK | ISMT_DESC_CWRL); + } + break; + + case I2C_SMBUS_BLOCK_PROC_CALL: + dev_dbg(dev, "I2C_SMBUS_BLOCK_PROC_CALL\n"); + if (data->block[0] > I2C_SMBUS_BLOCK_MAX) + return -EINVAL; + + dma_size = I2C_SMBUS_BLOCK_MAX; + desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, 1); + desc->wr_len_cmd = data->block[0] + 1; + desc->rd_len = dma_size; + desc->control |= ISMT_DESC_BLK; + dma_direction = DMA_BIDIRECTIONAL; + dma_buffer[0] = command; + memcpy(&dma_buffer[1], &data->block[1], data->block[0]); + break; + + case I2C_SMBUS_I2C_BLOCK_DATA: + /* Make sure the length is valid */ + if (data->block[0] < 1) + data->block[0] = 1; + + if (data->block[0] > I2C_SMBUS_BLOCK_MAX) + data->block[0] = I2C_SMBUS_BLOCK_MAX; + + if (read_write == I2C_SMBUS_WRITE) { + /* i2c Block Write */ + dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA: WRITE\n"); + dma_size = data->block[0] + 1; + dma_direction = DMA_TO_DEVICE; + desc->wr_len_cmd = dma_size; + desc->control |= ISMT_DESC_I2C; + dma_buffer[0] = command; + memcpy(&dma_buffer[1], &data->block[1], dma_size - 1); + } else { + /* i2c Block Read */ + dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA: READ\n"); + dma_size = data->block[0]; + dma_direction = DMA_FROM_DEVICE; + desc->rd_len = dma_size; + desc->wr_len_cmd = command; + desc->control |= (ISMT_DESC_I2C | ISMT_DESC_CWRL); + /* + * Per the "Table 15-15. I2C Commands", + * in the External Design Specification (EDS), + * (Document Number: 508084, Revision: 2.0), + * the _rw bit must be 0 + */ + desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, 0); + } + break; + + default: + dev_err(dev, "Unsupported transaction %d\n", + size); + return -EOPNOTSUPP; + } + + /* map the data buffer */ + if (dma_size != 0) { + dev_dbg(dev, " dev=%p\n", dev); + dev_dbg(dev, " data=%p\n", data); + dev_dbg(dev, " dma_buffer=%p\n", dma_buffer); + dev_dbg(dev, " dma_size=%d\n", dma_size); + dev_dbg(dev, " dma_direction=%d\n", dma_direction); + + dma_addr = dma_map_single(dev, + dma_buffer, + dma_size, + dma_direction); + + if (dma_mapping_error(dev, dma_addr)) { + dev_err(dev, "Error in mapping dma buffer %p\n", + dma_buffer); + return -EIO; + } + + dev_dbg(dev, " dma_addr = %pad\n", &dma_addr); + + desc->dptr_low = lower_32_bits(dma_addr); + desc->dptr_high = upper_32_bits(dma_addr); + } + + reinit_completion(&priv->cmp); + + /* Add the descriptor */ + ismt_submit_desc(priv); + + /* Now we wait for interrupt completion, 1s */ + time_left = wait_for_completion_timeout(&priv->cmp, HZ*1); + + /* unmap the data buffer */ + if (dma_size != 0) + dma_unmap_single(dev, dma_addr, dma_size, dma_direction); + + if (unlikely(!time_left)) { + dev_err(dev, "completion wait timed out\n"); + ret = -ETIMEDOUT; + goto out; + } + + /* do any post processing of the descriptor here */ + ret = ismt_process_desc(desc, data, priv, size, read_write); + +out: + /* Update the ring pointer */ + priv->head++; + priv->head %= ISMT_DESC_ENTRIES; + + return ret; +} + +/** + * ismt_func() - report which i2c commands are supported by this adapter + * @adap: the i2c host adapter + */ +static u32 ismt_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_SMBUS_QUICK | + I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_PROC_CALL | + I2C_FUNC_SMBUS_BLOCK_PROC_CALL | + I2C_FUNC_SMBUS_BLOCK_DATA | + I2C_FUNC_SMBUS_I2C_BLOCK | + I2C_FUNC_SMBUS_PEC; +} + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = ismt_access, + .functionality = ismt_func, +}; + +/** + * ismt_handle_isr() - interrupt handler bottom half + * @priv: iSMT private data + */ +static irqreturn_t ismt_handle_isr(struct ismt_priv *priv) +{ + complete(&priv->cmp); + + return IRQ_HANDLED; +} + + +/** + * ismt_do_interrupt() - IRQ interrupt handler + * @vec: interrupt vector + * @data: iSMT private data + */ +static irqreturn_t ismt_do_interrupt(int vec, void *data) +{ + u32 val; + struct ismt_priv *priv = data; + + /* + * check to see it's our interrupt, return IRQ_NONE if not ours + * since we are sharing interrupt + */ + val = readl(priv->smba + ISMT_MSTR_MSTS); + + if (!(val & (ISMT_MSTS_MIS | ISMT_MSTS_MEIS))) + return IRQ_NONE; + else + writel(val | ISMT_MSTS_MIS | ISMT_MSTS_MEIS, + priv->smba + ISMT_MSTR_MSTS); + + return ismt_handle_isr(priv); +} + +/** + * ismt_do_msi_interrupt() - MSI interrupt handler + * @vec: interrupt vector + * @data: iSMT private data + */ +static irqreturn_t ismt_do_msi_interrupt(int vec, void *data) +{ + return ismt_handle_isr(data); +} + +/** + * ismt_hw_init() - initialize the iSMT hardware + * @priv: iSMT private data + */ +static void ismt_hw_init(struct ismt_priv *priv) +{ + u32 val; + struct device *dev = &priv->pci_dev->dev; + + /* initialize the Master Descriptor Base Address (MDBA) */ + writeq(priv->io_rng_dma, priv->smba + ISMT_MSTR_MDBA); + + writeq(priv->log_dma, priv->smba + ISMT_GR_SMTICL); + + /* initialize the Master Control Register (MCTRL) */ + writel(ISMT_MCTRL_MEIE, priv->smba + ISMT_MSTR_MCTRL); + + /* initialize the Master Status Register (MSTS) */ + writel(0, priv->smba + ISMT_MSTR_MSTS); + + /* initialize the Master Descriptor Size (MDS) */ + val = readl(priv->smba + ISMT_MSTR_MDS); + writel((val & ~ISMT_MDS_MASK) | (ISMT_DESC_ENTRIES - 1), + priv->smba + ISMT_MSTR_MDS); + + /* + * Set the SMBus speed (could use this for slow HW debuggers) + */ + + val = readl(priv->smba + ISMT_SPGT); + + switch (bus_speed) { + case 0: + break; + + case 80: + dev_dbg(dev, "Setting SMBus clock to 80 kHz\n"); + writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_80K), + priv->smba + ISMT_SPGT); + break; + + case 100: + dev_dbg(dev, "Setting SMBus clock to 100 kHz\n"); + writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_100K), + priv->smba + ISMT_SPGT); + break; + + case 400: + dev_dbg(dev, "Setting SMBus clock to 400 kHz\n"); + writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_400K), + priv->smba + ISMT_SPGT); + break; + + case 1000: + dev_dbg(dev, "Setting SMBus clock to 1000 kHz\n"); + writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_1M), + priv->smba + ISMT_SPGT); + break; + + default: + dev_warn(dev, "Invalid SMBus clock speed, only 0, 80, 100, 400, and 1000 are valid\n"); + break; + } + + val = readl(priv->smba + ISMT_SPGT); + + switch (val & ISMT_SPGT_SPD_MASK) { + case ISMT_SPGT_SPD_80K: + bus_speed = 80; + break; + case ISMT_SPGT_SPD_100K: + bus_speed = 100; + break; + case ISMT_SPGT_SPD_400K: + bus_speed = 400; + break; + case ISMT_SPGT_SPD_1M: + bus_speed = 1000; + break; + } + dev_dbg(dev, "SMBus clock is running at %d kHz\n", bus_speed); +} + +/** + * ismt_dev_init() - initialize the iSMT data structures + * @priv: iSMT private data + */ +static int ismt_dev_init(struct ismt_priv *priv) +{ + /* allocate memory for the descriptor */ + priv->hw = dmam_alloc_coherent(&priv->pci_dev->dev, + (ISMT_DESC_ENTRIES + * sizeof(struct ismt_desc)), + &priv->io_rng_dma, + GFP_KERNEL); + if (!priv->hw) + return -ENOMEM; + + priv->head = 0; + init_completion(&priv->cmp); + + priv->log = dmam_alloc_coherent(&priv->pci_dev->dev, + ISMT_LOG_ENTRIES * sizeof(u32), + &priv->log_dma, GFP_KERNEL); + if (!priv->log) + return -ENOMEM; + + return 0; +} + +/** + * ismt_int_init() - initialize interrupts + * @priv: iSMT private data + */ +static int ismt_int_init(struct ismt_priv *priv) +{ + int err; + + /* Try using MSI interrupts */ + err = pci_enable_msi(priv->pci_dev); + if (err) + goto intx; + + err = devm_request_irq(&priv->pci_dev->dev, + priv->pci_dev->irq, + ismt_do_msi_interrupt, + 0, + "ismt-msi", + priv); + if (err) { + pci_disable_msi(priv->pci_dev); + goto intx; + } + + return 0; + + /* Try using legacy interrupts */ +intx: + dev_warn(&priv->pci_dev->dev, + "Unable to use MSI interrupts, falling back to legacy\n"); + + err = devm_request_irq(&priv->pci_dev->dev, + priv->pci_dev->irq, + ismt_do_interrupt, + IRQF_SHARED, + "ismt-intx", + priv); + if (err) { + dev_err(&priv->pci_dev->dev, "no usable interrupts\n"); + return err; + } + + return 0; +} + +static struct pci_driver ismt_driver; + +/** + * ismt_probe() - probe for iSMT devices + * @pdev: PCI-Express device + * @id: PCI-Express device ID + */ +static int +ismt_probe(struct pci_dev *pdev, const struct pci_device_id *id) +{ + int err; + struct ismt_priv *priv; + unsigned long start, len; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + pci_set_drvdata(pdev, priv); + + i2c_set_adapdata(&priv->adapter, priv); + priv->adapter.owner = THIS_MODULE; + priv->adapter.class = I2C_CLASS_HWMON; + priv->adapter.algo = &smbus_algorithm; + priv->adapter.dev.parent = &pdev->dev; + ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&pdev->dev)); + priv->adapter.retries = ISMT_MAX_RETRIES; + + priv->pci_dev = pdev; + + err = pcim_enable_device(pdev); + if (err) { + dev_err(&pdev->dev, "Failed to enable SMBus PCI device (%d)\n", + err); + return err; + } + + /* enable bus mastering */ + pci_set_master(pdev); + + /* Determine the address of the SMBus area */ + start = pci_resource_start(pdev, SMBBAR); + len = pci_resource_len(pdev, SMBBAR); + if (!start || !len) { + dev_err(&pdev->dev, + "SMBus base address uninitialized, upgrade BIOS\n"); + return -ENODEV; + } + + snprintf(priv->adapter.name, sizeof(priv->adapter.name), + "SMBus iSMT adapter at %lx", start); + + dev_dbg(&priv->pci_dev->dev, " start=0x%lX\n", start); + dev_dbg(&priv->pci_dev->dev, " len=0x%lX\n", len); + + err = acpi_check_resource_conflict(&pdev->resource[SMBBAR]); + if (err) { + dev_err(&pdev->dev, "ACPI resource conflict!\n"); + return err; + } + + err = pci_request_region(pdev, SMBBAR, ismt_driver.name); + if (err) { + dev_err(&pdev->dev, + "Failed to request SMBus region 0x%lx-0x%lx\n", + start, start + len); + return err; + } + + priv->smba = pcim_iomap(pdev, SMBBAR, len); + if (!priv->smba) { + dev_err(&pdev->dev, "Unable to ioremap SMBus BAR\n"); + return -ENODEV; + } + + err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); + if (err) { + dev_err(&pdev->dev, "dma_set_mask fail\n"); + return -ENODEV; + } + + err = ismt_dev_init(priv); + if (err) + return err; + + ismt_hw_init(priv); + + err = ismt_int_init(priv); + if (err) + return err; + + err = i2c_add_adapter(&priv->adapter); + if (err) + return -ENODEV; + return 0; +} + +/** + * ismt_remove() - release driver resources + * @pdev: PCI-Express device + */ +static void ismt_remove(struct pci_dev *pdev) +{ + struct ismt_priv *priv = pci_get_drvdata(pdev); + + i2c_del_adapter(&priv->adapter); +} + +static struct pci_driver ismt_driver = { + .name = "ismt_smbus", + .id_table = ismt_ids, + .probe = ismt_probe, + .remove = ismt_remove, +}; + +module_pci_driver(ismt_driver); + +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_AUTHOR("Bill E. Brown <bill.e.brown@intel.com>"); +MODULE_DESCRIPTION("Intel SMBus Message Transport (iSMT) driver"); diff --git a/drivers/i2c/busses/i2c-jz4780.c b/drivers/i2c/busses/i2c-jz4780.c new file mode 100644 index 000000000..55035cca0 --- /dev/null +++ b/drivers/i2c/busses/i2c-jz4780.c @@ -0,0 +1,869 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Ingenic JZ4780 I2C bus driver + * + * Copyright (C) 2006 - 2009 Ingenic Semiconductor Inc. + * Copyright (C) 2015 Imagination Technologies + * Copyright (C) 2019 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com> + */ + +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/time.h> + +#define JZ4780_I2C_CTRL 0x00 +#define JZ4780_I2C_TAR 0x04 +#define JZ4780_I2C_SAR 0x08 +#define JZ4780_I2C_DC 0x10 +#define JZ4780_I2C_SHCNT 0x14 +#define JZ4780_I2C_SLCNT 0x18 +#define JZ4780_I2C_FHCNT 0x1C +#define JZ4780_I2C_FLCNT 0x20 +#define JZ4780_I2C_INTST 0x2C +#define JZ4780_I2C_INTM 0x30 +#define JZ4780_I2C_RXTL 0x38 +#define JZ4780_I2C_TXTL 0x3C +#define JZ4780_I2C_CINTR 0x40 +#define JZ4780_I2C_CRXUF 0x44 +#define JZ4780_I2C_CRXOF 0x48 +#define JZ4780_I2C_CTXOF 0x4C +#define JZ4780_I2C_CRXREQ 0x50 +#define JZ4780_I2C_CTXABRT 0x54 +#define JZ4780_I2C_CRXDONE 0x58 +#define JZ4780_I2C_CACT 0x5C +#define JZ4780_I2C_CSTP 0x60 +#define JZ4780_I2C_CSTT 0x64 +#define JZ4780_I2C_CGC 0x68 +#define JZ4780_I2C_ENB 0x6C +#define JZ4780_I2C_STA 0x70 +#define JZ4780_I2C_TXABRT 0x80 +#define JZ4780_I2C_DMACR 0x88 +#define JZ4780_I2C_DMATDLR 0x8C +#define JZ4780_I2C_DMARDLR 0x90 +#define JZ4780_I2C_SDASU 0x94 +#define JZ4780_I2C_ACKGC 0x98 +#define JZ4780_I2C_ENSTA 0x9C +#define JZ4780_I2C_SDAHD 0xD0 +#define X1000_I2C_SDAHD 0x7C + +#define JZ4780_I2C_CTRL_STPHLD BIT(7) +#define JZ4780_I2C_CTRL_SLVDIS BIT(6) +#define JZ4780_I2C_CTRL_REST BIT(5) +#define JZ4780_I2C_CTRL_MATP BIT(4) +#define JZ4780_I2C_CTRL_SATP BIT(3) +#define JZ4780_I2C_CTRL_SPDF BIT(2) +#define JZ4780_I2C_CTRL_SPDS BIT(1) +#define JZ4780_I2C_CTRL_MD BIT(0) + +#define JZ4780_I2C_STA_SLVACT BIT(6) +#define JZ4780_I2C_STA_MSTACT BIT(5) +#define JZ4780_I2C_STA_RFF BIT(4) +#define JZ4780_I2C_STA_RFNE BIT(3) +#define JZ4780_I2C_STA_TFE BIT(2) +#define JZ4780_I2C_STA_TFNF BIT(1) +#define JZ4780_I2C_STA_ACT BIT(0) + +#define X1000_I2C_DC_STOP BIT(9) + +#define JZ4780_I2C_INTST_IGC BIT(11) +#define JZ4780_I2C_INTST_ISTT BIT(10) +#define JZ4780_I2C_INTST_ISTP BIT(9) +#define JZ4780_I2C_INTST_IACT BIT(8) +#define JZ4780_I2C_INTST_RXDN BIT(7) +#define JZ4780_I2C_INTST_TXABT BIT(6) +#define JZ4780_I2C_INTST_RDREQ BIT(5) +#define JZ4780_I2C_INTST_TXEMP BIT(4) +#define JZ4780_I2C_INTST_TXOF BIT(3) +#define JZ4780_I2C_INTST_RXFL BIT(2) +#define JZ4780_I2C_INTST_RXOF BIT(1) +#define JZ4780_I2C_INTST_RXUF BIT(0) + +#define JZ4780_I2C_INTM_MIGC BIT(11) +#define JZ4780_I2C_INTM_MISTT BIT(10) +#define JZ4780_I2C_INTM_MISTP BIT(9) +#define JZ4780_I2C_INTM_MIACT BIT(8) +#define JZ4780_I2C_INTM_MRXDN BIT(7) +#define JZ4780_I2C_INTM_MTXABT BIT(6) +#define JZ4780_I2C_INTM_MRDREQ BIT(5) +#define JZ4780_I2C_INTM_MTXEMP BIT(4) +#define JZ4780_I2C_INTM_MTXOF BIT(3) +#define JZ4780_I2C_INTM_MRXFL BIT(2) +#define JZ4780_I2C_INTM_MRXOF BIT(1) +#define JZ4780_I2C_INTM_MRXUF BIT(0) + +#define JZ4780_I2C_DC_READ BIT(8) + +#define JZ4780_I2C_SDAHD_HDENB BIT(8) + +#define JZ4780_I2C_ENB_I2C BIT(0) + +#define JZ4780_I2CSHCNT_ADJUST(n) (((n) - 8) < 6 ? 6 : ((n) - 8)) +#define JZ4780_I2CSLCNT_ADJUST(n) (((n) - 1) < 8 ? 8 : ((n) - 1)) +#define JZ4780_I2CFHCNT_ADJUST(n) (((n) - 8) < 6 ? 6 : ((n) - 8)) +#define JZ4780_I2CFLCNT_ADJUST(n) (((n) - 1) < 8 ? 8 : ((n) - 1)) + +#define JZ4780_I2C_FIFO_LEN 16 + +#define X1000_I2C_FIFO_LEN 64 + +#define JZ4780_I2C_TIMEOUT 300 + +#define BUFSIZE 200 + +enum ingenic_i2c_version { + ID_JZ4780, + ID_X1000, +}; + +/* ingenic_i2c_config: SoC specific config data. */ +struct ingenic_i2c_config { + enum ingenic_i2c_version version; + + int fifosize; + int tx_level; + int rx_level; +}; + +struct jz4780_i2c { + void __iomem *iomem; + int irq; + struct clk *clk; + struct i2c_adapter adap; + const struct ingenic_i2c_config *cdata; + + /* lock to protect rbuf and wbuf between xfer_rd/wr and irq handler */ + spinlock_t lock; + + /* beginning of lock scope */ + unsigned char *rbuf; + int rd_total_len; + int rd_data_xfered; + int rd_cmd_xfered; + + unsigned char *wbuf; + int wt_len; + + int is_write; + int stop_hold; + int speed; + + int data_buf[BUFSIZE]; + int cmd_buf[BUFSIZE]; + int cmd; + + /* end of lock scope */ + struct completion trans_waitq; +}; + +static inline unsigned short jz4780_i2c_readw(struct jz4780_i2c *i2c, + unsigned long offset) +{ + return readw(i2c->iomem + offset); +} + +static inline void jz4780_i2c_writew(struct jz4780_i2c *i2c, + unsigned long offset, unsigned short val) +{ + writew(val, i2c->iomem + offset); +} + +static int jz4780_i2c_disable(struct jz4780_i2c *i2c) +{ + unsigned short regval; + unsigned long loops = 5; + + jz4780_i2c_writew(i2c, JZ4780_I2C_ENB, 0); + + do { + regval = jz4780_i2c_readw(i2c, JZ4780_I2C_ENSTA); + if (!(regval & JZ4780_I2C_ENB_I2C)) + return 0; + + usleep_range(5000, 15000); + } while (--loops); + + dev_err(&i2c->adap.dev, "disable failed: ENSTA=0x%04x\n", regval); + return -ETIMEDOUT; +} + +static int jz4780_i2c_enable(struct jz4780_i2c *i2c) +{ + unsigned short regval; + unsigned long loops = 5; + + jz4780_i2c_writew(i2c, JZ4780_I2C_ENB, 1); + + do { + regval = jz4780_i2c_readw(i2c, JZ4780_I2C_ENSTA); + if (regval & JZ4780_I2C_ENB_I2C) + return 0; + + usleep_range(5000, 15000); + } while (--loops); + + dev_err(&i2c->adap.dev, "enable failed: ENSTA=0x%04x\n", regval); + return -ETIMEDOUT; +} + +static int jz4780_i2c_set_target(struct jz4780_i2c *i2c, unsigned char address) +{ + unsigned short regval; + unsigned long loops = 5; + + do { + regval = jz4780_i2c_readw(i2c, JZ4780_I2C_STA); + if ((regval & JZ4780_I2C_STA_TFE) && + !(regval & JZ4780_I2C_STA_MSTACT)) + break; + + usleep_range(5000, 15000); + } while (--loops); + + if (loops) { + jz4780_i2c_writew(i2c, JZ4780_I2C_TAR, address); + return 0; + } + + dev_err(&i2c->adap.dev, + "set device to address 0x%02x failed, STA=0x%04x\n", + address, regval); + + return -ENXIO; +} + +static int jz4780_i2c_set_speed(struct jz4780_i2c *i2c) +{ + int dev_clk_khz = clk_get_rate(i2c->clk) / 1000; + int cnt_high = 0; /* HIGH period count of the SCL clock */ + int cnt_low = 0; /* LOW period count of the SCL clock */ + int cnt_period = 0; /* period count of the SCL clock */ + int setup_time = 0; + int hold_time = 0; + unsigned short tmp = 0; + int i2c_clk = i2c->speed; + + if (jz4780_i2c_disable(i2c)) + dev_dbg(&i2c->adap.dev, "i2c not disabled\n"); + + /* + * 1 JZ4780_I2C cycle equals to cnt_period PCLK(i2c_clk) + * standard mode, min LOW and HIGH period are 4700 ns and 4000 ns + * fast mode, min LOW and HIGH period are 1300 ns and 600 ns + */ + cnt_period = dev_clk_khz / i2c_clk; + + if (i2c_clk <= 100) + cnt_high = (cnt_period * 4000) / (4700 + 4000); + else + cnt_high = (cnt_period * 600) / (1300 + 600); + + cnt_low = cnt_period - cnt_high; + + /* + * NOTE: JZ4780_I2C_CTRL_REST can't set when i2c enabled, because + * normal read are 2 messages, we cannot disable i2c controller + * between these two messages, this means that we must always set + * JZ4780_I2C_CTRL_REST when init JZ4780_I2C_CTRL + * + */ + if (i2c_clk <= 100) { + tmp = JZ4780_I2C_CTRL_SPDS | JZ4780_I2C_CTRL_REST + | JZ4780_I2C_CTRL_SLVDIS | JZ4780_I2C_CTRL_MD; + jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp); + + jz4780_i2c_writew(i2c, JZ4780_I2C_SHCNT, + JZ4780_I2CSHCNT_ADJUST(cnt_high)); + jz4780_i2c_writew(i2c, JZ4780_I2C_SLCNT, + JZ4780_I2CSLCNT_ADJUST(cnt_low)); + } else { + tmp = JZ4780_I2C_CTRL_SPDF | JZ4780_I2C_CTRL_REST + | JZ4780_I2C_CTRL_SLVDIS | JZ4780_I2C_CTRL_MD; + jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp); + + jz4780_i2c_writew(i2c, JZ4780_I2C_FHCNT, + JZ4780_I2CFHCNT_ADJUST(cnt_high)); + jz4780_i2c_writew(i2c, JZ4780_I2C_FLCNT, + JZ4780_I2CFLCNT_ADJUST(cnt_low)); + } + + /* + * a i2c device must internally provide a hold time at least 300ns + * tHD:DAT + * Standard Mode: min=300ns, max=3450ns + * Fast Mode: min=0ns, max=900ns + * tSU:DAT + * Standard Mode: min=250ns, max=infinite + * Fast Mode: min=100(250ns is recommended), max=infinite + * + * 1i2c_clk = 10^6 / dev_clk_khz + * on FPGA, dev_clk_khz = 12000, so 1i2c_clk = 1000/12 = 83ns + * on Pisces(1008M), dev_clk_khz=126000, so 1i2c_clk = 1000 / 126 = 8ns + * + * The actual hold time is (SDAHD + 1) * (i2c_clk period). + * + * Length of setup time calculated using (SDASU - 1) * (ic_clk_period) + * + */ + if (i2c_clk <= 100) { /* standard mode */ + setup_time = 300; + hold_time = 400; + } else { + setup_time = 450; + hold_time = 450; + } + + hold_time = ((hold_time * dev_clk_khz) / 1000000) - 1; + setup_time = ((setup_time * dev_clk_khz) / 1000000) + 1; + + if (setup_time > 255) + setup_time = 255; + + if (setup_time <= 0) + setup_time = 1; + + jz4780_i2c_writew(i2c, JZ4780_I2C_SDASU, setup_time); + + if (hold_time > 255) + hold_time = 255; + + if (hold_time >= 0) { + /*i2c hold time enable */ + if (i2c->cdata->version >= ID_X1000) { + jz4780_i2c_writew(i2c, X1000_I2C_SDAHD, hold_time); + } else { + hold_time |= JZ4780_I2C_SDAHD_HDENB; + jz4780_i2c_writew(i2c, JZ4780_I2C_SDAHD, hold_time); + } + } else { + /* disable hold time */ + if (i2c->cdata->version >= ID_X1000) + jz4780_i2c_writew(i2c, X1000_I2C_SDAHD, 0); + else + jz4780_i2c_writew(i2c, JZ4780_I2C_SDAHD, 0); + } + + return 0; +} + +static int jz4780_i2c_cleanup(struct jz4780_i2c *i2c) +{ + int ret; + unsigned long flags; + unsigned short tmp; + + spin_lock_irqsave(&i2c->lock, flags); + + /* can send stop now if need */ + if (i2c->cdata->version < ID_X1000) { + tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL); + tmp &= ~JZ4780_I2C_CTRL_STPHLD; + jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp); + } + + /* disable all interrupts first */ + jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, 0); + + /* then clear all interrupts */ + jz4780_i2c_readw(i2c, JZ4780_I2C_CTXABRT); + jz4780_i2c_readw(i2c, JZ4780_I2C_CINTR); + + /* then disable the controller */ + tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL); + tmp &= ~JZ4780_I2C_ENB_I2C; + jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp); + udelay(10); + tmp |= JZ4780_I2C_ENB_I2C; + jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp); + + spin_unlock_irqrestore(&i2c->lock, flags); + + ret = jz4780_i2c_disable(i2c); + if (ret) + dev_err(&i2c->adap.dev, + "unable to disable device during cleanup!\n"); + + if (unlikely(jz4780_i2c_readw(i2c, JZ4780_I2C_INTM) + & jz4780_i2c_readw(i2c, JZ4780_I2C_INTST))) + dev_err(&i2c->adap.dev, + "device has interrupts after a complete cleanup!\n"); + + return ret; +} + +static int jz4780_i2c_prepare(struct jz4780_i2c *i2c) +{ + jz4780_i2c_set_speed(i2c); + return jz4780_i2c_enable(i2c); +} + +static void jz4780_i2c_send_rcmd(struct jz4780_i2c *i2c, + int cmd_count, + int cmd_left) +{ + int i; + + for (i = 0; i < cmd_count - 1; i++) + jz4780_i2c_writew(i2c, JZ4780_I2C_DC, JZ4780_I2C_DC_READ); + + if ((cmd_left == 0) && (i2c->cdata->version >= ID_X1000)) + jz4780_i2c_writew(i2c, JZ4780_I2C_DC, + JZ4780_I2C_DC_READ | X1000_I2C_DC_STOP); + else + jz4780_i2c_writew(i2c, JZ4780_I2C_DC, JZ4780_I2C_DC_READ); +} + +static void jz4780_i2c_trans_done(struct jz4780_i2c *i2c) +{ + jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, 0); + complete(&i2c->trans_waitq); +} + +static irqreturn_t jz4780_i2c_irq(int irqno, void *dev_id) +{ + unsigned short tmp; + unsigned short intst; + unsigned short intmsk; + struct jz4780_i2c *i2c = dev_id; + + spin_lock(&i2c->lock); + intmsk = jz4780_i2c_readw(i2c, JZ4780_I2C_INTM); + intst = jz4780_i2c_readw(i2c, JZ4780_I2C_INTST); + + intst &= intmsk; + + if (intst & JZ4780_I2C_INTST_TXABT) { + jz4780_i2c_trans_done(i2c); + goto done; + } + + if (intst & JZ4780_I2C_INTST_RXOF) { + dev_dbg(&i2c->adap.dev, "received fifo overflow!\n"); + jz4780_i2c_trans_done(i2c); + goto done; + } + + /* + * When reading, always drain RX FIFO before we send more Read + * Commands to avoid fifo overrun + */ + if (i2c->is_write == 0) { + int rd_left; + + while ((jz4780_i2c_readw(i2c, JZ4780_I2C_STA) + & JZ4780_I2C_STA_RFNE)) { + *(i2c->rbuf++) = jz4780_i2c_readw(i2c, JZ4780_I2C_DC) + & 0xff; + i2c->rd_data_xfered++; + if (i2c->rd_data_xfered == i2c->rd_total_len) { + jz4780_i2c_trans_done(i2c); + goto done; + } + } + + rd_left = i2c->rd_total_len - i2c->rd_data_xfered; + + if (rd_left <= i2c->cdata->fifosize) + jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, rd_left - 1); + } + + if (intst & JZ4780_I2C_INTST_TXEMP) { + if (i2c->is_write == 0) { + int cmd_left = i2c->rd_total_len - i2c->rd_cmd_xfered; + int max_send = (i2c->cdata->fifosize - 1) + - (i2c->rd_cmd_xfered + - i2c->rd_data_xfered); + int cmd_to_send = min(cmd_left, max_send); + + if (i2c->rd_cmd_xfered != 0) + cmd_to_send = min(cmd_to_send, + i2c->cdata->fifosize + - i2c->cdata->tx_level - 1); + + if (cmd_to_send) { + i2c->rd_cmd_xfered += cmd_to_send; + cmd_left = i2c->rd_total_len - + i2c->rd_cmd_xfered; + jz4780_i2c_send_rcmd(i2c, + cmd_to_send, cmd_left); + + } + + if (cmd_left == 0) { + intmsk = jz4780_i2c_readw(i2c, JZ4780_I2C_INTM); + intmsk &= ~JZ4780_I2C_INTM_MTXEMP; + jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, intmsk); + + if (i2c->cdata->version < ID_X1000) { + tmp = jz4780_i2c_readw(i2c, + JZ4780_I2C_CTRL); + tmp &= ~JZ4780_I2C_CTRL_STPHLD; + jz4780_i2c_writew(i2c, + JZ4780_I2C_CTRL, tmp); + } + } + } else { + unsigned short data; + unsigned short i2c_sta; + + i2c_sta = jz4780_i2c_readw(i2c, JZ4780_I2C_STA); + + while ((i2c_sta & JZ4780_I2C_STA_TFNF) && + (i2c->wt_len > 0)) { + i2c_sta = jz4780_i2c_readw(i2c, JZ4780_I2C_STA); + data = *i2c->wbuf; + data &= ~JZ4780_I2C_DC_READ; + if ((i2c->wt_len == 1) && (!i2c->stop_hold) && + (i2c->cdata->version >= ID_X1000)) + data |= X1000_I2C_DC_STOP; + jz4780_i2c_writew(i2c, JZ4780_I2C_DC, data); + i2c->wbuf++; + i2c->wt_len--; + } + + if (i2c->wt_len == 0) { + if ((!i2c->stop_hold) && (i2c->cdata->version < + ID_X1000)) { + tmp = jz4780_i2c_readw(i2c, + JZ4780_I2C_CTRL); + tmp &= ~JZ4780_I2C_CTRL_STPHLD; + jz4780_i2c_writew(i2c, + JZ4780_I2C_CTRL, tmp); + } + + jz4780_i2c_trans_done(i2c); + goto done; + } + } + } + +done: + spin_unlock(&i2c->lock); + return IRQ_HANDLED; +} + +static void jz4780_i2c_txabrt(struct jz4780_i2c *i2c, int src) +{ + dev_dbg(&i2c->adap.dev, "txabrt: 0x%08x, cmd: %d, send: %d, recv: %d\n", + src, i2c->cmd, i2c->cmd_buf[i2c->cmd], i2c->data_buf[i2c->cmd]); +} + +static inline int jz4780_i2c_xfer_read(struct jz4780_i2c *i2c, + unsigned char *buf, int len, int cnt, + int idx) +{ + int ret = 0; + long timeout; + int wait_time = JZ4780_I2C_TIMEOUT * (len + 5); + unsigned short tmp; + unsigned long flags; + + memset(buf, 0, len); + + spin_lock_irqsave(&i2c->lock, flags); + + i2c->stop_hold = 0; + i2c->is_write = 0; + i2c->rbuf = buf; + i2c->rd_total_len = len; + i2c->rd_data_xfered = 0; + i2c->rd_cmd_xfered = 0; + + if (len <= i2c->cdata->fifosize) + jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, len - 1); + else + jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, i2c->cdata->rx_level); + + jz4780_i2c_writew(i2c, JZ4780_I2C_TXTL, i2c->cdata->tx_level); + + jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, + JZ4780_I2C_INTM_MRXFL | JZ4780_I2C_INTM_MTXEMP + | JZ4780_I2C_INTM_MTXABT | JZ4780_I2C_INTM_MRXOF); + + if (i2c->cdata->version < ID_X1000) { + tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL); + tmp |= JZ4780_I2C_CTRL_STPHLD; + jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp); + } + + spin_unlock_irqrestore(&i2c->lock, flags); + + timeout = wait_for_completion_timeout(&i2c->trans_waitq, + msecs_to_jiffies(wait_time)); + + if (!timeout) { + dev_err(&i2c->adap.dev, "irq read timeout\n"); + dev_dbg(&i2c->adap.dev, "send cmd count:%d %d\n", + i2c->cmd, i2c->cmd_buf[i2c->cmd]); + dev_dbg(&i2c->adap.dev, "receive data count:%d %d\n", + i2c->cmd, i2c->data_buf[i2c->cmd]); + ret = -EIO; + } + + tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_TXABRT); + if (tmp) { + jz4780_i2c_txabrt(i2c, tmp); + ret = -EIO; + } + + return ret; +} + +static inline int jz4780_i2c_xfer_write(struct jz4780_i2c *i2c, + unsigned char *buf, int len, + int cnt, int idx) +{ + int ret = 0; + int wait_time = JZ4780_I2C_TIMEOUT * (len + 5); + long timeout; + unsigned short tmp; + unsigned long flags; + + spin_lock_irqsave(&i2c->lock, flags); + + if (idx < (cnt - 1)) + i2c->stop_hold = 1; + else + i2c->stop_hold = 0; + + i2c->is_write = 1; + i2c->wbuf = buf; + i2c->wt_len = len; + + jz4780_i2c_writew(i2c, JZ4780_I2C_TXTL, i2c->cdata->tx_level); + + jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, JZ4780_I2C_INTM_MTXEMP + | JZ4780_I2C_INTM_MTXABT); + + if (i2c->cdata->version < ID_X1000) { + tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL); + tmp |= JZ4780_I2C_CTRL_STPHLD; + jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp); + } + + spin_unlock_irqrestore(&i2c->lock, flags); + + timeout = wait_for_completion_timeout(&i2c->trans_waitq, + msecs_to_jiffies(wait_time)); + if (timeout && !i2c->stop_hold) { + unsigned short i2c_sta; + int write_in_process; + + timeout = JZ4780_I2C_TIMEOUT * 100; + for (; timeout > 0; timeout--) { + i2c_sta = jz4780_i2c_readw(i2c, JZ4780_I2C_STA); + + write_in_process = (i2c_sta & JZ4780_I2C_STA_MSTACT) || + !(i2c_sta & JZ4780_I2C_STA_TFE); + if (!write_in_process) + break; + udelay(10); + } + } + + if (!timeout) { + dev_err(&i2c->adap.dev, "write wait timeout\n"); + ret = -EIO; + } + + tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_TXABRT); + if (tmp) { + jz4780_i2c_txabrt(i2c, tmp); + ret = -EIO; + } + + return ret; +} + +static int jz4780_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, + int count) +{ + int i = -EIO; + int ret = 0; + struct jz4780_i2c *i2c = adap->algo_data; + + ret = jz4780_i2c_prepare(i2c); + if (ret) { + dev_err(&i2c->adap.dev, "I2C prepare failed\n"); + goto out; + } + + if (msg->addr != jz4780_i2c_readw(i2c, JZ4780_I2C_TAR)) { + ret = jz4780_i2c_set_target(i2c, msg->addr); + if (ret) + goto out; + } + for (i = 0; i < count; i++, msg++) { + if (msg->flags & I2C_M_RD) + ret = jz4780_i2c_xfer_read(i2c, msg->buf, msg->len, + count, i); + else + ret = jz4780_i2c_xfer_write(i2c, msg->buf, msg->len, + count, i); + + if (ret) + goto out; + } + + ret = i; + +out: + jz4780_i2c_cleanup(i2c); + return ret; +} + +static u32 jz4780_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm jz4780_i2c_algorithm = { + .master_xfer = jz4780_i2c_xfer, + .functionality = jz4780_i2c_functionality, +}; + +static const struct ingenic_i2c_config jz4780_i2c_config = { + .version = ID_JZ4780, + + .fifosize = JZ4780_I2C_FIFO_LEN, + .tx_level = JZ4780_I2C_FIFO_LEN / 2, + .rx_level = JZ4780_I2C_FIFO_LEN / 2 - 1, +}; + +static const struct ingenic_i2c_config x1000_i2c_config = { + .version = ID_X1000, + + .fifosize = X1000_I2C_FIFO_LEN, + .tx_level = X1000_I2C_FIFO_LEN / 2, + .rx_level = X1000_I2C_FIFO_LEN / 2 - 1, +}; + +static const struct of_device_id jz4780_i2c_of_matches[] = { + { .compatible = "ingenic,jz4770-i2c", .data = &jz4780_i2c_config }, + { .compatible = "ingenic,jz4780-i2c", .data = &jz4780_i2c_config }, + { .compatible = "ingenic,x1000-i2c", .data = &x1000_i2c_config }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, jz4780_i2c_of_matches); + +static int jz4780_i2c_probe(struct platform_device *pdev) +{ + int ret = 0; + unsigned int clk_freq = 0; + unsigned short tmp; + struct jz4780_i2c *i2c; + + i2c = devm_kzalloc(&pdev->dev, sizeof(struct jz4780_i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->cdata = device_get_match_data(&pdev->dev); + if (!i2c->cdata) { + dev_err(&pdev->dev, "Error: No device match found\n"); + return -ENODEV; + } + + i2c->adap.owner = THIS_MODULE; + i2c->adap.algo = &jz4780_i2c_algorithm; + i2c->adap.algo_data = i2c; + i2c->adap.retries = 5; + i2c->adap.dev.parent = &pdev->dev; + i2c->adap.dev.of_node = pdev->dev.of_node; + sprintf(i2c->adap.name, "%s", pdev->name); + + init_completion(&i2c->trans_waitq); + spin_lock_init(&i2c->lock); + + i2c->iomem = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c->iomem)) + return PTR_ERR(i2c->iomem); + + platform_set_drvdata(pdev, i2c); + + i2c->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(i2c->clk)) + return PTR_ERR(i2c->clk); + + ret = clk_prepare_enable(i2c->clk); + if (ret) + return ret; + + ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency", + &clk_freq); + if (ret) { + dev_err(&pdev->dev, "clock-frequency not specified in DT\n"); + goto err; + } + + i2c->speed = clk_freq / 1000; + if (i2c->speed == 0) { + ret = -EINVAL; + dev_err(&pdev->dev, "clock-frequency minimum is 1000\n"); + goto err; + } + jz4780_i2c_set_speed(i2c); + + dev_info(&pdev->dev, "Bus frequency is %d KHz\n", i2c->speed); + + if (i2c->cdata->version < ID_X1000) { + tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL); + tmp &= ~JZ4780_I2C_CTRL_STPHLD; + jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp); + } + + jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, 0x0); + + ret = platform_get_irq(pdev, 0); + if (ret < 0) + goto err; + i2c->irq = ret; + ret = devm_request_irq(&pdev->dev, i2c->irq, jz4780_i2c_irq, 0, + dev_name(&pdev->dev), i2c); + if (ret) + goto err; + + ret = i2c_add_adapter(&i2c->adap); + if (ret < 0) + goto err; + + return 0; + +err: + clk_disable_unprepare(i2c->clk); + return ret; +} + +static void jz4780_i2c_remove(struct platform_device *pdev) +{ + struct jz4780_i2c *i2c = platform_get_drvdata(pdev); + + clk_disable_unprepare(i2c->clk); + i2c_del_adapter(&i2c->adap); +} + +static struct platform_driver jz4780_i2c_driver = { + .probe = jz4780_i2c_probe, + .remove_new = jz4780_i2c_remove, + .driver = { + .name = "jz4780-i2c", + .of_match_table = jz4780_i2c_of_matches, + }, +}; + +module_platform_driver(jz4780_i2c_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("ztyan<ztyan@ingenic.cn>"); +MODULE_DESCRIPTION("i2c driver for JZ4780 SoCs"); diff --git a/drivers/i2c/busses/i2c-kempld.c b/drivers/i2c/busses/i2c-kempld.c new file mode 100644 index 000000000..e01d75308 --- /dev/null +++ b/drivers/i2c/busses/i2c-kempld.c @@ -0,0 +1,397 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * I2C bus driver for Kontron COM modules + * + * Copyright (c) 2010-2013 Kontron Europe GmbH + * Author: Michael Brunner <michael.brunner@kontron.com> + * + * The driver is based on the i2c-ocores driver by Peter Korsgaard. + */ + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/i2c.h> +#include <linux/delay.h> +#include <linux/mfd/kempld.h> + +#define KEMPLD_I2C_PRELOW 0x0b +#define KEMPLD_I2C_PREHIGH 0x0c +#define KEMPLD_I2C_DATA 0x0e + +#define KEMPLD_I2C_CTRL 0x0d +#define I2C_CTRL_IEN 0x40 +#define I2C_CTRL_EN 0x80 + +#define KEMPLD_I2C_STAT 0x0f +#define I2C_STAT_IF 0x01 +#define I2C_STAT_TIP 0x02 +#define I2C_STAT_ARBLOST 0x20 +#define I2C_STAT_BUSY 0x40 +#define I2C_STAT_NACK 0x80 + +#define KEMPLD_I2C_CMD 0x0f +#define I2C_CMD_START 0x91 +#define I2C_CMD_STOP 0x41 +#define I2C_CMD_READ 0x21 +#define I2C_CMD_WRITE 0x11 +#define I2C_CMD_READ_ACK 0x21 +#define I2C_CMD_READ_NACK 0x29 +#define I2C_CMD_IACK 0x01 + +#define KEMPLD_I2C_FREQ_MAX 2700 /* 2.7 mHz */ +#define KEMPLD_I2C_FREQ_STD 100 /* 100 kHz */ + +enum { + STATE_DONE = 0, + STATE_INIT, + STATE_ADDR, + STATE_ADDR10, + STATE_START, + STATE_WRITE, + STATE_READ, + STATE_ERROR, +}; + +struct kempld_i2c_data { + struct device *dev; + struct kempld_device_data *pld; + struct i2c_adapter adap; + struct i2c_msg *msg; + int pos; + int nmsgs; + int state; + bool was_active; +}; + +static unsigned int bus_frequency = KEMPLD_I2C_FREQ_STD; +module_param(bus_frequency, uint, 0); +MODULE_PARM_DESC(bus_frequency, "Set I2C bus frequency in kHz (default=" + __MODULE_STRING(KEMPLD_I2C_FREQ_STD)")"); + +static int i2c_bus = -1; +module_param(i2c_bus, int, 0); +MODULE_PARM_DESC(i2c_bus, "Set I2C bus number (default=-1 for dynamic assignment)"); + +static bool i2c_gpio_mux; +module_param(i2c_gpio_mux, bool, 0); +MODULE_PARM_DESC(i2c_gpio_mux, "Enable I2C port on GPIO out (default=false)"); + +/* + * kempld_get_mutex must be called prior to calling this function. + */ +static int kempld_i2c_process(struct kempld_i2c_data *i2c) +{ + struct kempld_device_data *pld = i2c->pld; + u8 stat = kempld_read8(pld, KEMPLD_I2C_STAT); + struct i2c_msg *msg = i2c->msg; + u8 addr; + + /* Ready? */ + if (stat & I2C_STAT_TIP) + return -EBUSY; + + if (i2c->state == STATE_DONE || i2c->state == STATE_ERROR) { + /* Stop has been sent */ + kempld_write8(pld, KEMPLD_I2C_CMD, I2C_CMD_IACK); + if (i2c->state == STATE_ERROR) + return -EIO; + return 0; + } + + /* Error? */ + if (stat & I2C_STAT_ARBLOST) { + i2c->state = STATE_ERROR; + kempld_write8(pld, KEMPLD_I2C_CMD, I2C_CMD_STOP); + return -EAGAIN; + } + + if (i2c->state == STATE_INIT) { + if (stat & I2C_STAT_BUSY) + return -EBUSY; + + i2c->state = STATE_ADDR; + } + + if (i2c->state == STATE_ADDR) { + /* 10 bit address? */ + if (i2c->msg->flags & I2C_M_TEN) { + addr = 0xf0 | ((i2c->msg->addr >> 7) & 0x6); + /* Set read bit if necessary */ + addr |= (i2c->msg->flags & I2C_M_RD) ? 1 : 0; + i2c->state = STATE_ADDR10; + } else { + addr = i2c_8bit_addr_from_msg(i2c->msg); + i2c->state = STATE_START; + } + + kempld_write8(pld, KEMPLD_I2C_DATA, addr); + kempld_write8(pld, KEMPLD_I2C_CMD, I2C_CMD_START); + + return 0; + } + + /* Second part of 10 bit addressing */ + if (i2c->state == STATE_ADDR10) { + kempld_write8(pld, KEMPLD_I2C_DATA, i2c->msg->addr & 0xff); + kempld_write8(pld, KEMPLD_I2C_CMD, I2C_CMD_WRITE); + + i2c->state = STATE_START; + return 0; + } + + if (i2c->state == STATE_START || i2c->state == STATE_WRITE) { + i2c->state = (msg->flags & I2C_M_RD) ? STATE_READ : STATE_WRITE; + + if (stat & I2C_STAT_NACK) { + i2c->state = STATE_ERROR; + kempld_write8(pld, KEMPLD_I2C_CMD, I2C_CMD_STOP); + return -ENXIO; + } + } else { + msg->buf[i2c->pos++] = kempld_read8(pld, KEMPLD_I2C_DATA); + } + + if (i2c->pos >= msg->len) { + i2c->nmsgs--; + i2c->msg++; + i2c->pos = 0; + msg = i2c->msg; + + if (i2c->nmsgs) { + if (!(msg->flags & I2C_M_NOSTART)) { + i2c->state = STATE_ADDR; + return 0; + } else { + i2c->state = (msg->flags & I2C_M_RD) + ? STATE_READ : STATE_WRITE; + } + } else { + i2c->state = STATE_DONE; + kempld_write8(pld, KEMPLD_I2C_CMD, I2C_CMD_STOP); + return 0; + } + } + + if (i2c->state == STATE_READ) { + kempld_write8(pld, KEMPLD_I2C_CMD, i2c->pos == (msg->len - 1) ? + I2C_CMD_READ_NACK : I2C_CMD_READ_ACK); + } else { + kempld_write8(pld, KEMPLD_I2C_DATA, msg->buf[i2c->pos++]); + kempld_write8(pld, KEMPLD_I2C_CMD, I2C_CMD_WRITE); + } + + return 0; +} + +static int kempld_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct kempld_i2c_data *i2c = i2c_get_adapdata(adap); + struct kempld_device_data *pld = i2c->pld; + unsigned long timeout = jiffies + HZ; + int ret; + + i2c->msg = msgs; + i2c->pos = 0; + i2c->nmsgs = num; + i2c->state = STATE_INIT; + + /* Handle the transfer */ + while (time_before(jiffies, timeout)) { + kempld_get_mutex(pld); + ret = kempld_i2c_process(i2c); + kempld_release_mutex(pld); + + if (i2c->state == STATE_DONE || i2c->state == STATE_ERROR) + return (i2c->state == STATE_DONE) ? num : ret; + + if (ret == 0) + timeout = jiffies + HZ; + + usleep_range(5, 15); + } + + i2c->state = STATE_ERROR; + + return -ETIMEDOUT; +} + +/* + * kempld_get_mutex must be called prior to calling this function. + */ +static void kempld_i2c_device_init(struct kempld_i2c_data *i2c) +{ + struct kempld_device_data *pld = i2c->pld; + u16 prescale_corr; + long prescale; + u8 ctrl; + u8 stat; + u8 cfg; + + /* Make sure the device is disabled */ + ctrl = kempld_read8(pld, KEMPLD_I2C_CTRL); + ctrl &= ~(I2C_CTRL_EN | I2C_CTRL_IEN); + kempld_write8(pld, KEMPLD_I2C_CTRL, ctrl); + + if (bus_frequency > KEMPLD_I2C_FREQ_MAX) + bus_frequency = KEMPLD_I2C_FREQ_MAX; + + if (pld->info.spec_major == 1) + prescale = pld->pld_clock / (bus_frequency * 5) - 1000; + else + prescale = pld->pld_clock / (bus_frequency * 4) - 3000; + + if (prescale < 0) + prescale = 0; + + /* Round to the best matching value */ + prescale_corr = prescale / 1000; + if (prescale % 1000 >= 500) + prescale_corr++; + + kempld_write8(pld, KEMPLD_I2C_PRELOW, prescale_corr & 0xff); + kempld_write8(pld, KEMPLD_I2C_PREHIGH, prescale_corr >> 8); + + /* Activate I2C bus output on GPIO pins */ + cfg = kempld_read8(pld, KEMPLD_CFG); + if (i2c_gpio_mux) + cfg |= KEMPLD_CFG_GPIO_I2C_MUX; + else + cfg &= ~KEMPLD_CFG_GPIO_I2C_MUX; + kempld_write8(pld, KEMPLD_CFG, cfg); + + /* Enable the device */ + kempld_write8(pld, KEMPLD_I2C_CMD, I2C_CMD_IACK); + ctrl |= I2C_CTRL_EN; + kempld_write8(pld, KEMPLD_I2C_CTRL, ctrl); + + stat = kempld_read8(pld, KEMPLD_I2C_STAT); + if (stat & I2C_STAT_BUSY) + kempld_write8(pld, KEMPLD_I2C_CMD, I2C_CMD_STOP); +} + +static u32 kempld_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm kempld_i2c_algorithm = { + .master_xfer = kempld_i2c_xfer, + .functionality = kempld_i2c_func, +}; + +static const struct i2c_adapter kempld_i2c_adapter = { + .owner = THIS_MODULE, + .name = "i2c-kempld", + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD | + I2C_CLASS_DEPRECATED, + .algo = &kempld_i2c_algorithm, +}; + +static int kempld_i2c_probe(struct platform_device *pdev) +{ + struct kempld_device_data *pld = dev_get_drvdata(pdev->dev.parent); + struct kempld_i2c_data *i2c; + int ret; + u8 ctrl; + + i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->pld = pld; + i2c->dev = &pdev->dev; + i2c->adap = kempld_i2c_adapter; + i2c->adap.dev.parent = i2c->dev; + ACPI_COMPANION_SET(&i2c->adap.dev, ACPI_COMPANION(&pdev->dev)); + i2c_set_adapdata(&i2c->adap, i2c); + platform_set_drvdata(pdev, i2c); + + kempld_get_mutex(pld); + ctrl = kempld_read8(pld, KEMPLD_I2C_CTRL); + + if (ctrl & I2C_CTRL_EN) + i2c->was_active = true; + + kempld_i2c_device_init(i2c); + kempld_release_mutex(pld); + + /* Add I2C adapter to I2C tree */ + if (i2c_bus >= -1) + i2c->adap.nr = i2c_bus; + ret = i2c_add_numbered_adapter(&i2c->adap); + if (ret) + return ret; + + dev_info(i2c->dev, "I2C bus initialized at %dkHz\n", + bus_frequency); + + return 0; +} + +static void kempld_i2c_remove(struct platform_device *pdev) +{ + struct kempld_i2c_data *i2c = platform_get_drvdata(pdev); + struct kempld_device_data *pld = i2c->pld; + u8 ctrl; + + kempld_get_mutex(pld); + /* + * Disable I2C logic if it was not activated before the + * driver loaded + */ + if (!i2c->was_active) { + ctrl = kempld_read8(pld, KEMPLD_I2C_CTRL); + ctrl &= ~I2C_CTRL_EN; + kempld_write8(pld, KEMPLD_I2C_CTRL, ctrl); + } + kempld_release_mutex(pld); + + i2c_del_adapter(&i2c->adap); +} + +static int kempld_i2c_suspend(struct device *dev) +{ + struct kempld_i2c_data *i2c = dev_get_drvdata(dev); + struct kempld_device_data *pld = i2c->pld; + u8 ctrl; + + kempld_get_mutex(pld); + ctrl = kempld_read8(pld, KEMPLD_I2C_CTRL); + ctrl &= ~I2C_CTRL_EN; + kempld_write8(pld, KEMPLD_I2C_CTRL, ctrl); + kempld_release_mutex(pld); + + return 0; +} + +static int kempld_i2c_resume(struct device *dev) +{ + struct kempld_i2c_data *i2c = dev_get_drvdata(dev); + struct kempld_device_data *pld = i2c->pld; + + kempld_get_mutex(pld); + kempld_i2c_device_init(i2c); + kempld_release_mutex(pld); + + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(kempld_i2c_pm_ops, + kempld_i2c_suspend, kempld_i2c_resume); + +static struct platform_driver kempld_i2c_driver = { + .driver = { + .name = "kempld-i2c", + .pm = pm_sleep_ptr(&kempld_i2c_pm_ops), + }, + .probe = kempld_i2c_probe, + .remove_new = kempld_i2c_remove, +}; + +module_platform_driver(kempld_i2c_driver); + +MODULE_DESCRIPTION("KEM PLD I2C Driver"); +MODULE_AUTHOR("Michael Brunner <michael.brunner@kontron.com>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:kempld_i2c"); diff --git a/drivers/i2c/busses/i2c-lpc2k.c b/drivers/i2c/busses/i2c-lpc2k.c new file mode 100644 index 000000000..e3660333e --- /dev/null +++ b/drivers/i2c/busses/i2c-lpc2k.c @@ -0,0 +1,477 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2011 NXP Semiconductors + * + * Code portions referenced from the i2x-pxa and i2c-pnx drivers + * + * Make SMBus byte and word transactions work on LPC178x/7x + * Copyright (c) 2012 + * Alexander Potashev, Emcraft Systems, aspotashev@emcraft.com + * Anton Protopopov, Emcraft Systems, antonp@emcraft.com + * + * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com> + */ + +#include <linux/clk.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/time.h> + +/* LPC24xx register offsets and bits */ +#define LPC24XX_I2CONSET 0x00 +#define LPC24XX_I2STAT 0x04 +#define LPC24XX_I2DAT 0x08 +#define LPC24XX_I2ADDR 0x0c +#define LPC24XX_I2SCLH 0x10 +#define LPC24XX_I2SCLL 0x14 +#define LPC24XX_I2CONCLR 0x18 + +#define LPC24XX_AA BIT(2) +#define LPC24XX_SI BIT(3) +#define LPC24XX_STO BIT(4) +#define LPC24XX_STA BIT(5) +#define LPC24XX_I2EN BIT(6) + +#define LPC24XX_STO_AA (LPC24XX_STO | LPC24XX_AA) +#define LPC24XX_CLEAR_ALL (LPC24XX_AA | LPC24XX_SI | LPC24XX_STO | \ + LPC24XX_STA | LPC24XX_I2EN) + +/* I2C SCL clock has different duty cycle depending on mode */ +#define I2C_STD_MODE_DUTY 46 +#define I2C_FAST_MODE_DUTY 36 +#define I2C_FAST_MODE_PLUS_DUTY 38 + +/* + * 26 possible I2C status codes, but codes applicable only + * to master are listed here and used in this driver + */ +enum { + M_BUS_ERROR = 0x00, + M_START = 0x08, + M_REPSTART = 0x10, + MX_ADDR_W_ACK = 0x18, + MX_ADDR_W_NACK = 0x20, + MX_DATA_W_ACK = 0x28, + MX_DATA_W_NACK = 0x30, + M_DATA_ARB_LOST = 0x38, + MR_ADDR_R_ACK = 0x40, + MR_ADDR_R_NACK = 0x48, + MR_DATA_R_ACK = 0x50, + MR_DATA_R_NACK = 0x58, + M_I2C_IDLE = 0xf8, +}; + +struct lpc2k_i2c { + void __iomem *base; + struct clk *clk; + int irq; + wait_queue_head_t wait; + struct i2c_adapter adap; + struct i2c_msg *msg; + int msg_idx; + int msg_status; + int is_last; +}; + +static void i2c_lpc2k_reset(struct lpc2k_i2c *i2c) +{ + /* Will force clear all statuses */ + writel(LPC24XX_CLEAR_ALL, i2c->base + LPC24XX_I2CONCLR); + writel(0, i2c->base + LPC24XX_I2ADDR); + writel(LPC24XX_I2EN, i2c->base + LPC24XX_I2CONSET); +} + +static int i2c_lpc2k_clear_arb(struct lpc2k_i2c *i2c) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(1000); + + /* + * If the transfer needs to abort for some reason, we'll try to + * force a stop condition to clear any pending bus conditions + */ + writel(LPC24XX_STO, i2c->base + LPC24XX_I2CONSET); + + /* Wait for status change */ + while (readl(i2c->base + LPC24XX_I2STAT) != M_I2C_IDLE) { + if (time_after(jiffies, timeout)) { + /* Bus was not idle, try to reset adapter */ + i2c_lpc2k_reset(i2c); + return -EBUSY; + } + + cpu_relax(); + } + + return 0; +} + +static void i2c_lpc2k_pump_msg(struct lpc2k_i2c *i2c) +{ + unsigned char data; + u32 status; + + /* + * I2C in the LPC2xxx series is basically a state machine. + * Just run through the steps based on the current status. + */ + status = readl(i2c->base + LPC24XX_I2STAT); + + switch (status) { + case M_START: + case M_REPSTART: + /* Start bit was just sent out, send out addr and dir */ + data = i2c_8bit_addr_from_msg(i2c->msg); + + writel(data, i2c->base + LPC24XX_I2DAT); + writel(LPC24XX_STA, i2c->base + LPC24XX_I2CONCLR); + break; + + case MX_ADDR_W_ACK: + case MX_DATA_W_ACK: + /* + * Address or data was sent out with an ACK. If there is more + * data to send, send it now + */ + if (i2c->msg_idx < i2c->msg->len) { + writel(i2c->msg->buf[i2c->msg_idx], + i2c->base + LPC24XX_I2DAT); + } else if (i2c->is_last) { + /* Last message, send stop */ + writel(LPC24XX_STO_AA, i2c->base + LPC24XX_I2CONSET); + writel(LPC24XX_SI, i2c->base + LPC24XX_I2CONCLR); + i2c->msg_status = 0; + disable_irq_nosync(i2c->irq); + } else { + i2c->msg_status = 0; + disable_irq_nosync(i2c->irq); + } + + i2c->msg_idx++; + break; + + case MR_ADDR_R_ACK: + /* Receive first byte from slave */ + if (i2c->msg->len == 1) { + /* Last byte, return NACK */ + writel(LPC24XX_AA, i2c->base + LPC24XX_I2CONCLR); + } else { + /* Not last byte, return ACK */ + writel(LPC24XX_AA, i2c->base + LPC24XX_I2CONSET); + } + + writel(LPC24XX_STA, i2c->base + LPC24XX_I2CONCLR); + break; + + case MR_DATA_R_NACK: + /* + * The I2C shows NACK status on reads, so we need to accept + * the NACK as an ACK here. This should be ok, as the real + * BACK would of been caught on the address write. + */ + case MR_DATA_R_ACK: + /* Data was received */ + if (i2c->msg_idx < i2c->msg->len) { + i2c->msg->buf[i2c->msg_idx] = + readl(i2c->base + LPC24XX_I2DAT); + } + + /* If transfer is done, send STOP */ + if (i2c->msg_idx >= i2c->msg->len - 1 && i2c->is_last) { + writel(LPC24XX_STO_AA, i2c->base + LPC24XX_I2CONSET); + writel(LPC24XX_SI, i2c->base + LPC24XX_I2CONCLR); + i2c->msg_status = 0; + } + + /* Message is done */ + if (i2c->msg_idx >= i2c->msg->len - 1) { + i2c->msg_status = 0; + disable_irq_nosync(i2c->irq); + } + + /* + * One pre-last data input, send NACK to tell the slave that + * this is going to be the last data byte to be transferred. + */ + if (i2c->msg_idx >= i2c->msg->len - 2) { + /* One byte left to receive - NACK */ + writel(LPC24XX_AA, i2c->base + LPC24XX_I2CONCLR); + } else { + /* More than one byte left to receive - ACK */ + writel(LPC24XX_AA, i2c->base + LPC24XX_I2CONSET); + } + + writel(LPC24XX_STA, i2c->base + LPC24XX_I2CONCLR); + i2c->msg_idx++; + break; + + case MX_ADDR_W_NACK: + case MX_DATA_W_NACK: + case MR_ADDR_R_NACK: + /* NACK processing is done */ + writel(LPC24XX_STO_AA, i2c->base + LPC24XX_I2CONSET); + i2c->msg_status = -ENXIO; + disable_irq_nosync(i2c->irq); + break; + + case M_DATA_ARB_LOST: + /* Arbitration lost */ + i2c->msg_status = -EAGAIN; + + /* Release the I2C bus */ + writel(LPC24XX_STA | LPC24XX_STO, i2c->base + LPC24XX_I2CONCLR); + disable_irq_nosync(i2c->irq); + break; + + default: + /* Unexpected statuses */ + i2c->msg_status = -EIO; + disable_irq_nosync(i2c->irq); + break; + } + + /* Exit on failure or all bytes transferred */ + if (i2c->msg_status != -EBUSY) + wake_up(&i2c->wait); + + /* + * If `msg_status` is zero, then `lpc2k_process_msg()` + * is responsible for clearing the SI flag. + */ + if (i2c->msg_status != 0) + writel(LPC24XX_SI, i2c->base + LPC24XX_I2CONCLR); +} + +static int lpc2k_process_msg(struct lpc2k_i2c *i2c, int msgidx) +{ + /* A new transfer is kicked off by initiating a start condition */ + if (!msgidx) { + writel(LPC24XX_STA, i2c->base + LPC24XX_I2CONSET); + } else { + /* + * A multi-message I2C transfer continues where the + * previous I2C transfer left off and uses the + * current condition of the I2C adapter. + */ + if (unlikely(i2c->msg->flags & I2C_M_NOSTART)) { + WARN_ON(i2c->msg->len == 0); + + if (!(i2c->msg->flags & I2C_M_RD)) { + /* Start transmit of data */ + writel(i2c->msg->buf[0], + i2c->base + LPC24XX_I2DAT); + i2c->msg_idx++; + } + } else { + /* Start or repeated start */ + writel(LPC24XX_STA, i2c->base + LPC24XX_I2CONSET); + } + + writel(LPC24XX_SI, i2c->base + LPC24XX_I2CONCLR); + } + + enable_irq(i2c->irq); + + /* Wait for transfer completion */ + if (wait_event_timeout(i2c->wait, i2c->msg_status != -EBUSY, + msecs_to_jiffies(1000)) == 0) { + disable_irq_nosync(i2c->irq); + + return -ETIMEDOUT; + } + + return i2c->msg_status; +} + +static int i2c_lpc2k_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int msg_num) +{ + struct lpc2k_i2c *i2c = i2c_get_adapdata(adap); + int ret, i; + u32 stat; + + /* Check for bus idle condition */ + stat = readl(i2c->base + LPC24XX_I2STAT); + if (stat != M_I2C_IDLE) { + /* Something is holding the bus, try to clear it */ + return i2c_lpc2k_clear_arb(i2c); + } + + /* Process a single message at a time */ + for (i = 0; i < msg_num; i++) { + /* Save message pointer and current message data index */ + i2c->msg = &msgs[i]; + i2c->msg_idx = 0; + i2c->msg_status = -EBUSY; + i2c->is_last = (i == (msg_num - 1)); + + ret = lpc2k_process_msg(i2c, i); + if (ret) + return ret; + } + + return msg_num; +} + +static irqreturn_t i2c_lpc2k_handler(int irq, void *dev_id) +{ + struct lpc2k_i2c *i2c = dev_id; + + if (readl(i2c->base + LPC24XX_I2CONSET) & LPC24XX_SI) { + i2c_lpc2k_pump_msg(i2c); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static u32 i2c_lpc2k_functionality(struct i2c_adapter *adap) +{ + /* Only emulated SMBus for now */ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm i2c_lpc2k_algorithm = { + .master_xfer = i2c_lpc2k_xfer, + .functionality = i2c_lpc2k_functionality, +}; + +static int i2c_lpc2k_probe(struct platform_device *pdev) +{ + struct lpc2k_i2c *i2c; + u32 bus_clk_rate; + u32 scl_high; + u32 clkrate; + int ret; + + i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c->base)) + return PTR_ERR(i2c->base); + + i2c->irq = platform_get_irq(pdev, 0); + if (i2c->irq < 0) + return i2c->irq; + + init_waitqueue_head(&i2c->wait); + + i2c->clk = devm_clk_get_enabled(&pdev->dev, NULL); + if (IS_ERR(i2c->clk)) { + dev_err(&pdev->dev, "failed to enable clock.\n"); + return PTR_ERR(i2c->clk); + } + + ret = devm_request_irq(&pdev->dev, i2c->irq, i2c_lpc2k_handler, 0, + dev_name(&pdev->dev), i2c); + if (ret < 0) { + dev_err(&pdev->dev, "can't request interrupt.\n"); + return ret; + } + + disable_irq_nosync(i2c->irq); + + /* Place controller is a known state */ + i2c_lpc2k_reset(i2c); + + ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency", + &bus_clk_rate); + if (ret) + bus_clk_rate = I2C_MAX_STANDARD_MODE_FREQ; + + clkrate = clk_get_rate(i2c->clk); + if (clkrate == 0) { + dev_err(&pdev->dev, "can't get I2C base clock\n"); + return -EINVAL; + } + + /* Setup I2C dividers to generate clock with proper duty cycle */ + clkrate = clkrate / bus_clk_rate; + if (bus_clk_rate <= I2C_MAX_STANDARD_MODE_FREQ) + scl_high = (clkrate * I2C_STD_MODE_DUTY) / 100; + else if (bus_clk_rate <= I2C_MAX_FAST_MODE_FREQ) + scl_high = (clkrate * I2C_FAST_MODE_DUTY) / 100; + else + scl_high = (clkrate * I2C_FAST_MODE_PLUS_DUTY) / 100; + + writel(scl_high, i2c->base + LPC24XX_I2SCLH); + writel(clkrate - scl_high, i2c->base + LPC24XX_I2SCLL); + + platform_set_drvdata(pdev, i2c); + + i2c_set_adapdata(&i2c->adap, i2c); + i2c->adap.owner = THIS_MODULE; + strscpy(i2c->adap.name, "LPC2K I2C adapter", sizeof(i2c->adap.name)); + i2c->adap.algo = &i2c_lpc2k_algorithm; + i2c->adap.dev.parent = &pdev->dev; + i2c->adap.dev.of_node = pdev->dev.of_node; + + ret = i2c_add_adapter(&i2c->adap); + if (ret < 0) + return ret; + + dev_info(&pdev->dev, "LPC2K I2C adapter\n"); + + return 0; +} + +static void i2c_lpc2k_remove(struct platform_device *dev) +{ + struct lpc2k_i2c *i2c = platform_get_drvdata(dev); + + i2c_del_adapter(&i2c->adap); +} + +static int i2c_lpc2k_suspend(struct device *dev) +{ + struct lpc2k_i2c *i2c = dev_get_drvdata(dev); + + clk_disable(i2c->clk); + + return 0; +} + +static int i2c_lpc2k_resume(struct device *dev) +{ + struct lpc2k_i2c *i2c = dev_get_drvdata(dev); + + clk_enable(i2c->clk); + i2c_lpc2k_reset(i2c); + + return 0; +} + +static const struct dev_pm_ops i2c_lpc2k_dev_pm_ops = { + .suspend_noirq = i2c_lpc2k_suspend, + .resume_noirq = i2c_lpc2k_resume, +}; + +static const struct of_device_id lpc2k_i2c_match[] = { + { .compatible = "nxp,lpc1788-i2c" }, + {}, +}; +MODULE_DEVICE_TABLE(of, lpc2k_i2c_match); + +static struct platform_driver i2c_lpc2k_driver = { + .probe = i2c_lpc2k_probe, + .remove_new = i2c_lpc2k_remove, + .driver = { + .name = "lpc2k-i2c", + .pm = pm_sleep_ptr(&i2c_lpc2k_dev_pm_ops), + .of_match_table = lpc2k_i2c_match, + }, +}; +module_platform_driver(i2c_lpc2k_driver); + +MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>"); +MODULE_DESCRIPTION("I2C driver for LPC2xxx devices"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:lpc2k-i2c"); diff --git a/drivers/i2c/busses/i2c-ls2x.c b/drivers/i2c/busses/i2c-ls2x.c new file mode 100644 index 000000000..ebae60357 --- /dev/null +++ b/drivers/i2c/busses/i2c-ls2x.c @@ -0,0 +1,370 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Loongson-2K/Loongson LS7A I2C master mode driver + * + * Copyright (C) 2013 Loongson Technology Corporation Limited. + * Copyright (C) 2014-2017 Lemote, Inc. + * Copyright (C) 2018-2022 Loongson Technology Corporation Limited. + * + * Originally written by liushaozong + * Rewritten for mainline by Binbin Zhou <zhoubinbin@loongson.cn> + */ + +#include <linux/bits.h> +#include <linux/completion.h> +#include <linux/device.h> +#include <linux/iopoll.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pm_runtime.h> +#include <linux/platform_device.h> +#include <linux/property.h> +#include <linux/units.h> + +/* I2C Registers */ +#define I2C_LS2X_PRER 0x0 /* Freq Division Register(16 bits) */ +#define I2C_LS2X_CTR 0x2 /* Control Register */ +#define I2C_LS2X_TXR 0x3 /* Transport Data Register */ +#define I2C_LS2X_RXR 0x3 /* Receive Data Register */ +#define I2C_LS2X_CR 0x4 /* Command Control Register */ +#define I2C_LS2X_SR 0x4 /* State Register */ + +/* Command Control Register Bit */ +#define LS2X_CR_START BIT(7) /* Start signal */ +#define LS2X_CR_STOP BIT(6) /* Stop signal */ +#define LS2X_CR_READ BIT(5) /* Read signal */ +#define LS2X_CR_WRITE BIT(4) /* Write signal */ +#define LS2X_CR_ACK BIT(3) /* Response signal */ +#define LS2X_CR_IACK BIT(0) /* Interrupt response signal */ + +/* State Register Bit */ +#define LS2X_SR_NOACK BIT(7) /* Receive NACK */ +#define LS2X_SR_BUSY BIT(6) /* Bus busy state */ +#define LS2X_SR_AL BIT(5) /* Arbitration lost */ +#define LS2X_SR_TIP BIT(1) /* Transmission state */ +#define LS2X_SR_IF BIT(0) /* Interrupt flag */ + +/* Control Register Bit */ +#define LS2X_CTR_EN BIT(7) /* 0: I2c frequency setting 1: Normal */ +#define LS2X_CTR_IEN BIT(6) /* Enable i2c interrupt */ +#define LS2X_CTR_MST BIT(5) /* 0: Slave mode 1: Master mode */ +#define CTR_FREQ_MASK GENMASK(7, 6) +#define CTR_READY_MASK GENMASK(7, 5) + +/* The PCLK frequency from LPB */ +#define LS2X_I2C_PCLK_FREQ (50 * HZ_PER_MHZ) + +/* The default bus frequency, which is an empirical value */ +#define LS2X_I2C_FREQ_STD (33 * HZ_PER_KHZ) + +struct ls2x_i2c_priv { + struct i2c_adapter adapter; + void __iomem *base; + struct i2c_timings i2c_t; + struct completion cmd_complete; +}; + +/* + * Interrupt service routine. + * This gets called whenever an I2C interrupt occurs. + */ +static irqreturn_t ls2x_i2c_isr(int this_irq, void *dev_id) +{ + struct ls2x_i2c_priv *priv = dev_id; + + if (!(readb(priv->base + I2C_LS2X_SR) & LS2X_SR_IF)) + return IRQ_NONE; + + writeb(LS2X_CR_IACK, priv->base + I2C_LS2X_CR); + complete(&priv->cmd_complete); + return IRQ_HANDLED; +} + +/* + * The ls2x i2c controller supports standard mode and fast mode, so the + * maximum bus frequency is '400kHz'. + * The bus frequency is set to the empirical value of '33KHz' by default, + * but it can also be taken from ACPI or FDT for compatibility with more + * devices. + */ +static void ls2x_i2c_adjust_bus_speed(struct ls2x_i2c_priv *priv) +{ + struct i2c_timings *t = &priv->i2c_t; + struct device *dev = priv->adapter.dev.parent; + u32 acpi_speed = i2c_acpi_find_bus_speed(dev); + + i2c_parse_fw_timings(dev, t, false); + + if (acpi_speed || t->bus_freq_hz) + t->bus_freq_hz = max(t->bus_freq_hz, acpi_speed); + else + t->bus_freq_hz = LS2X_I2C_FREQ_STD; + + /* Calculate and set i2c frequency. */ + writew(LS2X_I2C_PCLK_FREQ / (5 * t->bus_freq_hz) - 1, + priv->base + I2C_LS2X_PRER); +} + +static void ls2x_i2c_init(struct ls2x_i2c_priv *priv) +{ + /* Set i2c frequency setting mode and disable interrupts. */ + writeb(readb(priv->base + I2C_LS2X_CTR) & ~CTR_FREQ_MASK, + priv->base + I2C_LS2X_CTR); + + ls2x_i2c_adjust_bus_speed(priv); + + /* Set i2c normal operating mode and enable interrupts. */ + writeb(readb(priv->base + I2C_LS2X_CTR) | CTR_READY_MASK, + priv->base + I2C_LS2X_CTR); +} + +static int ls2x_i2c_xfer_byte(struct ls2x_i2c_priv *priv, u8 txdata, u8 *rxdatap) +{ + u8 rxdata; + unsigned long time_left; + + writeb(txdata, priv->base + I2C_LS2X_CR); + + time_left = wait_for_completion_timeout(&priv->cmd_complete, + priv->adapter.timeout); + if (!time_left) + return -ETIMEDOUT; + + rxdata = readb(priv->base + I2C_LS2X_SR); + if (rxdatap) + *rxdatap = rxdata; + + return 0; +} + +static int ls2x_i2c_send_byte(struct ls2x_i2c_priv *priv, u8 txdata) +{ + int ret; + u8 rxdata; + + ret = ls2x_i2c_xfer_byte(priv, txdata, &rxdata); + if (ret) + return ret; + + if (rxdata & LS2X_SR_AL) + return -EAGAIN; + + if (rxdata & LS2X_SR_NOACK) + return -ENXIO; + + return 0; +} + +static int ls2x_i2c_stop(struct ls2x_i2c_priv *priv) +{ + u8 value; + + writeb(LS2X_CR_STOP, priv->base + I2C_LS2X_CR); + return readb_poll_timeout(priv->base + I2C_LS2X_SR, value, + !(value & LS2X_SR_BUSY), 100, + jiffies_to_usecs(priv->adapter.timeout)); +} + +static int ls2x_i2c_start(struct ls2x_i2c_priv *priv, struct i2c_msg *msgs) +{ + reinit_completion(&priv->cmd_complete); + + writeb(i2c_8bit_addr_from_msg(msgs), priv->base + I2C_LS2X_TXR); + return ls2x_i2c_send_byte(priv, LS2X_CR_START | LS2X_CR_WRITE); +} + +static int ls2x_i2c_rx(struct ls2x_i2c_priv *priv, struct i2c_msg *msg) +{ + int ret; + u8 rxdata, *buf = msg->buf; + u16 len = msg->len; + + /* Contains steps to send start condition and address. */ + ret = ls2x_i2c_start(priv, msg); + if (ret) + return ret; + + while (len--) { + ret = ls2x_i2c_xfer_byte(priv, + LS2X_CR_READ | (len ? 0 : LS2X_CR_ACK), + &rxdata); + if (ret) + return ret; + + *buf++ = readb(priv->base + I2C_LS2X_RXR); + } + + return 0; +} + +static int ls2x_i2c_tx(struct ls2x_i2c_priv *priv, struct i2c_msg *msg) +{ + int ret; + u8 *buf = msg->buf; + u16 len = msg->len; + + /* Contains steps to send start condition and address. */ + ret = ls2x_i2c_start(priv, msg); + if (ret) + return ret; + + while (len--) { + writeb(*buf++, priv->base + I2C_LS2X_TXR); + + ret = ls2x_i2c_send_byte(priv, LS2X_CR_WRITE); + if (ret) + return ret; + } + + return 0; +} + +static int ls2x_i2c_xfer_one(struct ls2x_i2c_priv *priv, + struct i2c_msg *msg, bool stop) +{ + int ret; + + if (msg->flags & I2C_M_RD) + ret = ls2x_i2c_rx(priv, msg); + else + ret = ls2x_i2c_tx(priv, msg); + + if (ret < 0) { + /* Fatel error. Needs reinit. */ + if (ret == -ETIMEDOUT) + ls2x_i2c_init(priv); + + return ret; + } + + if (stop) { + /* Failed to issue STOP. Needs reinit. */ + ret = ls2x_i2c_stop(priv); + if (ret) + ls2x_i2c_init(priv); + } + + return ret; +} + +static int ls2x_i2c_master_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + int ret; + struct i2c_msg *msg, *emsg = msgs + num; + struct ls2x_i2c_priv *priv = i2c_get_adapdata(adap); + + for (msg = msgs; msg < emsg; msg++) { + ret = ls2x_i2c_xfer_one(priv, msg, msg == emsg - 1); + if (ret) + return ret; + } + + return num; +} + +static unsigned int ls2x_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm ls2x_i2c_algo = { + .master_xfer = ls2x_i2c_master_xfer, + .functionality = ls2x_i2c_func, +}; + +static int ls2x_i2c_probe(struct platform_device *pdev) +{ + int ret, irq; + struct i2c_adapter *adap; + struct ls2x_i2c_priv *priv; + struct device *dev = &pdev->dev; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + /* Map hardware registers */ + priv->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->base)) + return PTR_ERR(priv->base); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + /* Add the i2c adapter */ + adap = &priv->adapter; + adap->retries = 5; + adap->nr = pdev->id; + adap->dev.parent = dev; + adap->owner = THIS_MODULE; + adap->algo = &ls2x_i2c_algo; + adap->timeout = msecs_to_jiffies(100); + device_set_node(&adap->dev, dev_fwnode(dev)); + i2c_set_adapdata(adap, priv); + strscpy(adap->name, pdev->name, sizeof(adap->name)); + init_completion(&priv->cmd_complete); + platform_set_drvdata(pdev, priv); + + ls2x_i2c_init(priv); + + ret = devm_request_irq(dev, irq, ls2x_i2c_isr, IRQF_SHARED, "ls2x-i2c", + priv); + if (ret < 0) + return dev_err_probe(dev, ret, "Unable to request irq %d\n", irq); + + return devm_i2c_add_adapter(dev, adap); +} + +static int ls2x_i2c_suspend(struct device *dev) +{ + struct ls2x_i2c_priv *priv = dev_get_drvdata(dev); + + /* Disable interrupts */ + writeb(readb(priv->base + I2C_LS2X_CTR) & ~LS2X_CTR_IEN, + priv->base + I2C_LS2X_CTR); + + return 0; +} + +static int ls2x_i2c_resume(struct device *dev) +{ + ls2x_i2c_init(dev_get_drvdata(dev)); + return 0; +} + +static DEFINE_RUNTIME_DEV_PM_OPS(ls2x_i2c_pm_ops, + ls2x_i2c_suspend, ls2x_i2c_resume, NULL); + +static const struct of_device_id ls2x_i2c_id_table[] = { + { .compatible = "loongson,ls2k-i2c" }, + { .compatible = "loongson,ls7a-i2c" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, ls2x_i2c_id_table); + +static const struct acpi_device_id ls2x_i2c_acpi_match[] = { + { "LOON0004" }, /* Loongson LS7A */ + { } +}; +MODULE_DEVICE_TABLE(acpi, ls2x_i2c_acpi_match); + +static struct platform_driver ls2x_i2c_driver = { + .probe = ls2x_i2c_probe, + .driver = { + .name = "ls2x-i2c", + .pm = pm_sleep_ptr(&ls2x_i2c_pm_ops), + .of_match_table = ls2x_i2c_id_table, + .acpi_match_table = ls2x_i2c_acpi_match, + }, +}; +module_platform_driver(ls2x_i2c_driver); + +MODULE_DESCRIPTION("Loongson LS2X I2C Bus driver"); +MODULE_AUTHOR("Loongson Technology Corporation Limited"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-mchp-pci1xxxx.c b/drivers/i2c/busses/i2c-mchp-pci1xxxx.c new file mode 100644 index 000000000..5ef136c3e --- /dev/null +++ b/drivers/i2c/busses/i2c-mchp-pci1xxxx.c @@ -0,0 +1,1212 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Microchip PCI1XXXX I2C adapter driver for PCIe Switch + * which has I2C controller in one of its downstream functions + * + * Copyright (C) 2021 - 2022 Microchip Technology Inc. + * + * Authors: Tharun Kumar P <tharunkumar.pasumarthi@microchip.com> + * Kumaravel Thiagarajan <kumaravel.thiagarajan@microchip.com> + */ + +#include <linux/bits.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/i2c-smbus.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/types.h> + +#define SMBUS_MAST_CORE_ADDR_BASE 0x00000 +#define SMBUS_MAST_SYS_REG_ADDR_BASE 0x01000 + +/* SMB register space. */ +#define SMB_CORE_CTRL_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x00) + +#define SMB_CORE_CTRL_ESO BIT(6) +#define SMB_CORE_CTRL_FW_ACK BIT(4) +#define SMB_CORE_CTRL_ACK BIT(0) + +#define SMB_CORE_CMD_REG_OFF3 (SMBUS_MAST_CORE_ADDR_BASE + 0x0F) +#define SMB_CORE_CMD_REG_OFF2 (SMBUS_MAST_CORE_ADDR_BASE + 0x0E) +#define SMB_CORE_CMD_REG_OFF1 (SMBUS_MAST_CORE_ADDR_BASE + 0x0D) + +#define SMB_CORE_CMD_READM BIT(4) +#define SMB_CORE_CMD_STOP BIT(2) +#define SMB_CORE_CMD_START BIT(0) + +#define SMB_CORE_CMD_REG_OFF0 (SMBUS_MAST_CORE_ADDR_BASE + 0x0C) + +#define SMB_CORE_CMD_M_PROCEED BIT(1) +#define SMB_CORE_CMD_M_RUN BIT(0) + +#define SMB_CORE_SR_HOLD_TIME_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x18) + +/* + * SR_HOLD_TIME_XK_TICKS field will indicate the number of ticks of the + * baud clock required to program 'Hold Time' at X KHz. + */ +#define SR_HOLD_TIME_100K_TICKS 150 +#define SR_HOLD_TIME_400K_TICKS 20 +#define SR_HOLD_TIME_1000K_TICKS 12 + +#define SMB_CORE_COMPLETION_REG_OFF3 (SMBUS_MAST_CORE_ADDR_BASE + 0x23) + +#define COMPLETION_MDONE BIT(6) +#define COMPLETION_IDLE BIT(5) +#define COMPLETION_MNAKX BIT(0) + +#define SMB_CORE_IDLE_SCALING_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x24) + +/* + * FAIR_BUS_IDLE_MIN_XK_TICKS field will indicate the number of ticks of + * the baud clock required to program 'fair idle delay' at X KHz. Fair idle + * delay establishes the MCTP T(IDLE_DELAY) period. + */ +#define FAIR_BUS_IDLE_MIN_100K_TICKS 992 +#define FAIR_BUS_IDLE_MIN_400K_TICKS 500 +#define FAIR_BUS_IDLE_MIN_1000K_TICKS 500 + +/* + * FAIR_IDLE_DELAY_XK_TICKS field will indicate the number of ticks of the + * baud clock required to satisfy the fairness protocol at X KHz. + */ +#define FAIR_IDLE_DELAY_100K_TICKS 963 +#define FAIR_IDLE_DELAY_400K_TICKS 156 +#define FAIR_IDLE_DELAY_1000K_TICKS 156 + +#define SMB_IDLE_SCALING_100K \ + ((FAIR_IDLE_DELAY_100K_TICKS << 16) | FAIR_BUS_IDLE_MIN_100K_TICKS) +#define SMB_IDLE_SCALING_400K \ + ((FAIR_IDLE_DELAY_400K_TICKS << 16) | FAIR_BUS_IDLE_MIN_400K_TICKS) +#define SMB_IDLE_SCALING_1000K \ + ((FAIR_IDLE_DELAY_1000K_TICKS << 16) | FAIR_BUS_IDLE_MIN_1000K_TICKS) + +#define SMB_CORE_CONFIG_REG3 (SMBUS_MAST_CORE_ADDR_BASE + 0x2B) + +#define SMB_CONFIG3_ENMI BIT(6) +#define SMB_CONFIG3_ENIDI BIT(5) + +#define SMB_CORE_CONFIG_REG2 (SMBUS_MAST_CORE_ADDR_BASE + 0x2A) +#define SMB_CORE_CONFIG_REG1 (SMBUS_MAST_CORE_ADDR_BASE + 0x29) + +#define SMB_CONFIG1_ASR BIT(7) +#define SMB_CONFIG1_ENAB BIT(2) +#define SMB_CONFIG1_RESET BIT(1) +#define SMB_CONFIG1_FEN BIT(0) + +#define SMB_CORE_BUS_CLK_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x2C) + +/* + * BUS_CLK_XK_LOW_PERIOD_TICKS field defines the number of I2C Baud Clock + * periods that make up the low phase of the I2C/SMBus bus clock at X KHz. + */ +#define BUS_CLK_100K_LOW_PERIOD_TICKS 156 +#define BUS_CLK_400K_LOW_PERIOD_TICKS 41 +#define BUS_CLK_1000K_LOW_PERIOD_TICKS 15 + +/* + * BUS_CLK_XK_HIGH_PERIOD_TICKS field defines the number of I2C Baud Clock + * periods that make up the high phase of the I2C/SMBus bus clock at X KHz. + */ +#define BUS_CLK_100K_HIGH_PERIOD_TICKS 154 +#define BUS_CLK_400K_HIGH_PERIOD_TICKS 35 +#define BUS_CLK_1000K_HIGH_PERIOD_TICKS 14 + +#define BUS_CLK_100K \ + ((BUS_CLK_100K_HIGH_PERIOD_TICKS << 8) | BUS_CLK_100K_LOW_PERIOD_TICKS) +#define BUS_CLK_400K \ + ((BUS_CLK_400K_HIGH_PERIOD_TICKS << 8) | BUS_CLK_400K_LOW_PERIOD_TICKS) +#define BUS_CLK_1000K \ + ((BUS_CLK_1000K_HIGH_PERIOD_TICKS << 8) | BUS_CLK_1000K_LOW_PERIOD_TICKS) + +#define SMB_CORE_CLK_SYNC_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x3C) + +/* + * CLK_SYNC_XK defines the number of clock cycles to sync up to the external + * clock before comparing the internal and external clocks for clock stretching + * at X KHz. + */ +#define CLK_SYNC_100K 4 +#define CLK_SYNC_400K 4 +#define CLK_SYNC_1000K 4 + +#define SMB_CORE_DATA_TIMING_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x40) + +/* + * + * FIRST_START_HOLD_XK_TICKS will indicate the number of ticks of the baud + * clock required to program 'FIRST_START_HOLD' timer at X KHz. This timer + * determines the SCLK hold time following SDAT driven low during the first + * START bit in a transfer. + */ +#define FIRST_START_HOLD_100K_TICKS 23 +#define FIRST_START_HOLD_400K_TICKS 8 +#define FIRST_START_HOLD_1000K_TICKS 12 + +/* + * STOP_SETUP_XK_TICKS will indicate the number of ticks of the baud clock + * required to program 'STOP_SETUP' timer at X KHz. This timer determines the + * SDAT setup time from the rising edge of SCLK for a STOP condition. + */ +#define STOP_SETUP_100K_TICKS 150 +#define STOP_SETUP_400K_TICKS 20 +#define STOP_SETUP_1000K_TICKS 12 + +/* + * RESTART_SETUP_XK_TICKS will indicate the number of ticks of the baud clock + * required to program 'RESTART_SETUP' timer at X KHz. This timer determines the + * SDAT setup time from the rising edge of SCLK for a repeated START condition. + */ +#define RESTART_SETUP_100K_TICKS 156 +#define RESTART_SETUP_400K_TICKS 20 +#define RESTART_SETUP_1000K_TICKS 12 + +/* + * DATA_HOLD_XK_TICKS will indicate the number of ticks of the baud clock + * required to program 'DATA_HOLD' timer at X KHz. This timer determines the + * SDAT hold time following SCLK driven low. + */ +#define DATA_HOLD_100K_TICKS 12 +#define DATA_HOLD_400K_TICKS 2 +#define DATA_HOLD_1000K_TICKS 2 + +#define DATA_TIMING_100K \ + ((FIRST_START_HOLD_100K_TICKS << 24) | (STOP_SETUP_100K_TICKS << 16) | \ + (RESTART_SETUP_100K_TICKS << 8) | DATA_HOLD_100K_TICKS) +#define DATA_TIMING_400K \ + ((FIRST_START_HOLD_400K_TICKS << 24) | (STOP_SETUP_400K_TICKS << 16) | \ + (RESTART_SETUP_400K_TICKS << 8) | DATA_HOLD_400K_TICKS) +#define DATA_TIMING_1000K \ + ((FIRST_START_HOLD_1000K_TICKS << 24) | (STOP_SETUP_1000K_TICKS << 16) | \ + (RESTART_SETUP_1000K_TICKS << 8) | DATA_HOLD_1000K_TICKS) + +#define SMB_CORE_TO_SCALING_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x44) + +/* + * BUS_IDLE_MIN_XK_TICKS defines Bus Idle Minimum Time. + * Bus Idle Minimum time = BUS_IDLE_MIN[7:0] x Baud_Clock_Period x + * (BUS_IDLE_MIN_XK_TICKS[7] ? 4,1) + */ +#define BUS_IDLE_MIN_100K_TICKS 36UL +#define BUS_IDLE_MIN_400K_TICKS 10UL +#define BUS_IDLE_MIN_1000K_TICKS 4UL + +/* + * CTRL_CUM_TIME_OUT_XK_TICKS defines SMBus Controller Cumulative Time-Out. + * SMBus Controller Cumulative Time-Out duration = + * CTRL_CUM_TIME_OUT_XK_TICKS[7:0] x Baud_Clock_Period x 2048 + */ +#define CTRL_CUM_TIME_OUT_100K_TICKS 76 +#define CTRL_CUM_TIME_OUT_400K_TICKS 76 +#define CTRL_CUM_TIME_OUT_1000K_TICKS 76 + +/* + * TARGET_CUM_TIME_OUT_XK_TICKS defines SMBus Target Cumulative Time-Out duration. + * SMBus Target Cumulative Time-Out duration = TARGET_CUM_TIME_OUT_XK_TICKS[7:0] x + * Baud_Clock_Period x 4096 + */ +#define TARGET_CUM_TIME_OUT_100K_TICKS 95 +#define TARGET_CUM_TIME_OUT_400K_TICKS 95 +#define TARGET_CUM_TIME_OUT_1000K_TICKS 95 + +/* + * CLOCK_HIGH_TIME_OUT_XK defines Clock High time out period. + * Clock High time out period = CLOCK_HIGH_TIME_OUT_XK[7:0] x Baud_Clock_Period x 8 + */ +#define CLOCK_HIGH_TIME_OUT_100K_TICKS 97 +#define CLOCK_HIGH_TIME_OUT_400K_TICKS 97 +#define CLOCK_HIGH_TIME_OUT_1000K_TICKS 97 + +#define TO_SCALING_100K \ + ((BUS_IDLE_MIN_100K_TICKS << 24) | (CTRL_CUM_TIME_OUT_100K_TICKS << 16) | \ + (TARGET_CUM_TIME_OUT_100K_TICKS << 8) | CLOCK_HIGH_TIME_OUT_100K_TICKS) +#define TO_SCALING_400K \ + ((BUS_IDLE_MIN_400K_TICKS << 24) | (CTRL_CUM_TIME_OUT_400K_TICKS << 16) | \ + (TARGET_CUM_TIME_OUT_400K_TICKS << 8) | CLOCK_HIGH_TIME_OUT_400K_TICKS) +#define TO_SCALING_1000K \ + ((BUS_IDLE_MIN_1000K_TICKS << 24) | (CTRL_CUM_TIME_OUT_1000K_TICKS << 16) | \ + (TARGET_CUM_TIME_OUT_1000K_TICKS << 8) | CLOCK_HIGH_TIME_OUT_1000K_TICKS) + +#define I2C_SCL_PAD_CTRL_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x100) +#define I2C_SDA_PAD_CTRL_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x101) + +#define I2C_FOD_EN BIT(4) +#define I2C_PULL_UP_EN BIT(3) +#define I2C_PULL_DOWN_EN BIT(2) +#define I2C_INPUT_EN BIT(1) +#define I2C_OUTPUT_EN BIT(0) + +#define SMBUS_CONTROL_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x200) + +#define CTL_RESET_COUNTERS BIT(3) +#define CTL_TRANSFER_DIR BIT(2) +#define CTL_HOST_FIFO_ENTRY BIT(1) +#define CTL_RUN BIT(0) + +#define I2C_DIRN_WRITE 0 +#define I2C_DIRN_READ 1 + +#define SMBUS_STATUS_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x204) + +#define STA_DMA_TERM BIT(7) +#define STA_DMA_REQ BIT(6) +#define STA_THRESHOLD BIT(2) +#define STA_BUF_FULL BIT(1) +#define STA_BUF_EMPTY BIT(0) + +#define SMBUS_INTR_STAT_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x208) + +#define INTR_STAT_DMA_TERM BIT(7) +#define INTR_STAT_THRESHOLD BIT(2) +#define INTR_STAT_BUF_FULL BIT(1) +#define INTR_STAT_BUF_EMPTY BIT(0) + +#define SMBUS_INTR_MSK_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x20C) + +#define INTR_MSK_DMA_TERM BIT(7) +#define INTR_MSK_THRESHOLD BIT(2) +#define INTR_MSK_BUF_FULL BIT(1) +#define INTR_MSK_BUF_EMPTY BIT(0) + +#define ALL_NW_LAYER_INTERRUPTS \ + (INTR_MSK_DMA_TERM | INTR_MSK_THRESHOLD | INTR_MSK_BUF_FULL | \ + INTR_MSK_BUF_EMPTY) + +#define SMBUS_MCU_COUNTER_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x214) + +#define SMBALERT_MST_PAD_CTRL_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x230) + +#define SMBALERT_MST_PU BIT(0) + +#define SMBUS_GEN_INT_STAT_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x23C) + +#define SMBUS_GEN_INT_MASK_REG_OFF (SMBUS_MAST_CORE_ADDR_BASE + 0x240) + +#define SMBALERT_INTR_MASK BIT(10) +#define I2C_BUF_MSTR_INTR_MASK BIT(9) +#define I2C_INTR_MASK BIT(8) +#define SMBALERT_WAKE_INTR_MASK BIT(2) +#define I2C_BUF_MSTR_WAKE_INTR_MASK BIT(1) +#define I2C_WAKE_INTR_MASK BIT(0) + +#define ALL_HIGH_LAYER_INTR \ + (SMBALERT_INTR_MASK | I2C_BUF_MSTR_INTR_MASK | I2C_INTR_MASK | \ + SMBALERT_WAKE_INTR_MASK | I2C_BUF_MSTR_WAKE_INTR_MASK | \ + I2C_WAKE_INTR_MASK) + +#define SMBUS_RESET_REG (SMBUS_MAST_CORE_ADDR_BASE + 0x248) + +#define PERI_SMBUS_D3_RESET_DIS BIT(16) + +#define SMBUS_MST_BUF (SMBUS_MAST_CORE_ADDR_BASE + 0x280) + +#define SMBUS_BUF_MAX_SIZE 0x80 + +#define I2C_FLAGS_DIRECT_MODE BIT(7) +#define I2C_FLAGS_POLLING_MODE BIT(6) +#define I2C_FLAGS_STOP BIT(5) +#define I2C_FLAGS_SMB_BLK_READ BIT(4) + +#define PCI1XXXX_I2C_TIMEOUT_MS 1000 + +/* General Purpose Register. */ +#define SMB_GPR_REG (SMBUS_MAST_CORE_ADDR_BASE + 0x1000 + 0x0c00 + \ + 0x00) + +/* Lock Register. */ +#define SMB_GPR_LOCK_REG (SMBUS_MAST_CORE_ADDR_BASE + 0x1000 + 0x0000 + \ + 0x00A0) + +#define SMBUS_PERI_LOCK BIT(3) + +struct pci1xxxx_i2c { + struct completion i2c_xfer_done; + bool i2c_xfer_in_progress; + struct i2c_adapter adap; + void __iomem *i2c_base; + u32 freq; + u32 flags; +}; + +static int set_sys_lock(struct pci1xxxx_i2c *i2c) +{ + void __iomem *p = i2c->i2c_base + SMB_GPR_LOCK_REG; + u8 data; + + writel(SMBUS_PERI_LOCK, p); + data = readl(p); + if (data != SMBUS_PERI_LOCK) + return -EPERM; + + return 0; +} + +static int release_sys_lock(struct pci1xxxx_i2c *i2c) +{ + void __iomem *p = i2c->i2c_base + SMB_GPR_LOCK_REG; + u8 data; + + data = readl(p); + if (data != SMBUS_PERI_LOCK) + return 0; + + writel(0, p); + data = readl(p); + if (data & SMBUS_PERI_LOCK) + return -EPERM; + + return 0; +} + +static void pci1xxxx_ack_high_level_intr(struct pci1xxxx_i2c *i2c, u16 intr_msk) +{ + writew(intr_msk, i2c->i2c_base + SMBUS_GEN_INT_STAT_REG_OFF); +} + +static void pci1xxxx_i2c_configure_smbalert_pin(struct pci1xxxx_i2c *i2c, + bool enable) +{ + void __iomem *p = i2c->i2c_base + SMBALERT_MST_PAD_CTRL_REG_OFF; + u8 regval; + + regval = readb(p); + + if (enable) + regval |= SMBALERT_MST_PU; + else + regval &= ~SMBALERT_MST_PU; + + writeb(regval, p); +} + +static void pci1xxxx_i2c_send_start_stop(struct pci1xxxx_i2c *i2c, bool start) +{ + void __iomem *p = i2c->i2c_base + SMB_CORE_CMD_REG_OFF1; + u8 regval; + + regval = readb(p); + + if (start) + regval |= SMB_CORE_CMD_START; + else + regval |= SMB_CORE_CMD_STOP; + + writeb(regval, p); +} + +/* + * When accessing the core control reg, we should not do a read modified write + * as they are write '1' to clear bits. Instead we need to write with the + * specific bits that needs to be set. + */ +static void pci1xxxx_i2c_set_clear_FW_ACK(struct pci1xxxx_i2c *i2c, bool set) +{ + u8 regval; + + if (set) + regval = SMB_CORE_CTRL_FW_ACK | SMB_CORE_CTRL_ESO | SMB_CORE_CTRL_ACK; + else + regval = SMB_CORE_CTRL_ESO | SMB_CORE_CTRL_ACK; + + writeb(regval, i2c->i2c_base + SMB_CORE_CTRL_REG_OFF); +} + +static void pci1xxxx_i2c_buffer_write(struct pci1xxxx_i2c *i2c, u8 slaveaddr, + u8 transferlen, unsigned char *buf) +{ + void __iomem *p = i2c->i2c_base + SMBUS_MST_BUF; + + if (slaveaddr) + writeb(slaveaddr, p++); + + if (buf) + memcpy_toio(p, buf, transferlen); +} + +/* + * When accessing the core control reg, we should not do a read modified write + * as there are write '1' to clear bits. Instead we need to write with the + * specific bits that needs to be set. + */ +static void pci1xxxx_i2c_enable_ESO(struct pci1xxxx_i2c *i2c) +{ + writeb(SMB_CORE_CTRL_ESO, i2c->i2c_base + SMB_CORE_CTRL_REG_OFF); +} + +static void pci1xxxx_i2c_reset_counters(struct pci1xxxx_i2c *i2c) +{ + void __iomem *p = i2c->i2c_base + SMBUS_CONTROL_REG_OFF; + u8 regval; + + regval = readb(p); + regval |= CTL_RESET_COUNTERS; + writeb(regval, p); +} + +static void pci1xxxx_i2c_set_transfer_dir(struct pci1xxxx_i2c *i2c, u8 direction) +{ + void __iomem *p = i2c->i2c_base + SMBUS_CONTROL_REG_OFF; + u8 regval; + + regval = readb(p); + if (direction == I2C_DIRN_WRITE) + regval &= ~CTL_TRANSFER_DIR; + else + regval |= CTL_TRANSFER_DIR; + + writeb(regval, p); +} + +static void pci1xxxx_i2c_set_mcu_count(struct pci1xxxx_i2c *i2c, u8 count) +{ + writeb(count, i2c->i2c_base + SMBUS_MCU_COUNTER_REG_OFF); +} + +static void pci1xxxx_i2c_set_read_count(struct pci1xxxx_i2c *i2c, u8 readcount) +{ + writeb(readcount, i2c->i2c_base + SMB_CORE_CMD_REG_OFF3); +} + +static void pci1xxxx_i2c_set_write_count(struct pci1xxxx_i2c *i2c, u8 writecount) +{ + writeb(writecount, i2c->i2c_base + SMB_CORE_CMD_REG_OFF2); +} + +static void pci1xxxx_i2c_set_DMA_run(struct pci1xxxx_i2c *i2c) +{ + void __iomem *p = i2c->i2c_base + SMBUS_CONTROL_REG_OFF; + u8 regval; + + regval = readb(p); + regval |= CTL_RUN; + writeb(regval, p); +} + +static void pci1xxxx_i2c_set_mrun_proceed(struct pci1xxxx_i2c *i2c) +{ + void __iomem *p = i2c->i2c_base + SMB_CORE_CMD_REG_OFF0; + u8 regval; + + regval = readb(p); + regval |= SMB_CORE_CMD_M_RUN; + regval |= SMB_CORE_CMD_M_PROCEED; + writeb(regval, p); +} + +static void pci1xxxx_i2c_start_DMA(struct pci1xxxx_i2c *i2c) +{ + pci1xxxx_i2c_set_DMA_run(i2c); + pci1xxxx_i2c_set_mrun_proceed(i2c); +} + +static void pci1xxxx_i2c_config_asr(struct pci1xxxx_i2c *i2c, bool enable) +{ + void __iomem *p = i2c->i2c_base + SMB_CORE_CONFIG_REG1; + u8 regval; + + regval = readb(p); + if (enable) + regval |= SMB_CONFIG1_ASR; + else + regval &= ~SMB_CONFIG1_ASR; + writeb(regval, p); +} + +static irqreturn_t pci1xxxx_i2c_isr(int irq, void *dev) +{ + struct pci1xxxx_i2c *i2c = dev; + void __iomem *p1 = i2c->i2c_base + SMBUS_GEN_INT_STAT_REG_OFF; + void __iomem *p2 = i2c->i2c_base + SMBUS_INTR_STAT_REG_OFF; + irqreturn_t intr_handled = IRQ_NONE; + u16 reg1; + u8 reg3; + + /* + * Read the SMBus interrupt status register to see if the + * DMA_TERM interrupt has caused this callback. + */ + reg1 = readw(p1); + + if (reg1 & I2C_BUF_MSTR_INTR_MASK) { + reg3 = readb(p2); + if (reg3 & INTR_STAT_DMA_TERM) { + complete(&i2c->i2c_xfer_done); + intr_handled = IRQ_HANDLED; + writeb(INTR_STAT_DMA_TERM, p2); + } + pci1xxxx_ack_high_level_intr(i2c, I2C_BUF_MSTR_INTR_MASK); + } + + if (reg1 & SMBALERT_INTR_MASK) { + intr_handled = IRQ_HANDLED; + pci1xxxx_ack_high_level_intr(i2c, SMBALERT_INTR_MASK); + } + + return intr_handled; +} + +static void pci1xxxx_i2c_set_count(struct pci1xxxx_i2c *i2c, u8 mcucount, + u8 writecount, u8 readcount) +{ + pci1xxxx_i2c_set_mcu_count(i2c, mcucount); + pci1xxxx_i2c_set_write_count(i2c, writecount); + pci1xxxx_i2c_set_read_count(i2c, readcount); +} + +static void pci1xxxx_i2c_set_readm(struct pci1xxxx_i2c *i2c, bool enable) +{ + void __iomem *p = i2c->i2c_base + SMB_CORE_CMD_REG_OFF1; + u8 regval; + + regval = readb(p); + if (enable) + regval |= SMB_CORE_CMD_READM; + else + regval &= ~SMB_CORE_CMD_READM; + + writeb(regval, p); +} + +static void pci1xxxx_ack_nw_layer_intr(struct pci1xxxx_i2c *i2c, u8 ack_intr_msk) +{ + writeb(ack_intr_msk, i2c->i2c_base + SMBUS_INTR_STAT_REG_OFF); +} + +static void pci1xxxx_config_nw_layer_intr(struct pci1xxxx_i2c *i2c, + u8 intr_msk, bool enable) +{ + void __iomem *p = i2c->i2c_base + SMBUS_INTR_MSK_REG_OFF; + u8 regval; + + regval = readb(p); + if (enable) + regval &= ~intr_msk; + else + regval |= intr_msk; + + writeb(regval, p); +} + +static void pci1xxxx_i2c_config_padctrl(struct pci1xxxx_i2c *i2c, bool enable) +{ + void __iomem *p1 = i2c->i2c_base + I2C_SCL_PAD_CTRL_REG_OFF; + void __iomem *p2 = i2c->i2c_base + I2C_SDA_PAD_CTRL_REG_OFF; + u8 regval; + + regval = readb(p1); + if (enable) + regval |= I2C_INPUT_EN | I2C_OUTPUT_EN; + else + regval &= ~(I2C_INPUT_EN | I2C_OUTPUT_EN); + + writeb(regval, p1); + + regval = readb(p2); + if (enable) + regval |= I2C_INPUT_EN | I2C_OUTPUT_EN; + else + regval &= ~(I2C_INPUT_EN | I2C_OUTPUT_EN); + + writeb(regval, p2); +} + +static void pci1xxxx_i2c_set_mode(struct pci1xxxx_i2c *i2c) +{ + void __iomem *p = i2c->i2c_base + SMBUS_CONTROL_REG_OFF; + u8 regval; + + regval = readb(p); + if (i2c->flags & I2C_FLAGS_DIRECT_MODE) + regval &= ~CTL_HOST_FIFO_ENTRY; + else + regval |= CTL_HOST_FIFO_ENTRY; + + writeb(regval, p); +} + +static void pci1xxxx_i2c_config_high_level_intr(struct pci1xxxx_i2c *i2c, + u16 intr_msk, bool enable) +{ + void __iomem *p = i2c->i2c_base + SMBUS_GEN_INT_MASK_REG_OFF; + u16 regval; + + regval = readw(p); + if (enable) + regval &= ~intr_msk; + else + regval |= intr_msk; + writew(regval, p); +} + +static void pci1xxxx_i2c_configure_core_reg(struct pci1xxxx_i2c *i2c, bool enable) +{ + void __iomem *p1 = i2c->i2c_base + SMB_CORE_CONFIG_REG1; + void __iomem *p3 = i2c->i2c_base + SMB_CORE_CONFIG_REG3; + u8 reg1; + u8 reg3; + + reg1 = readb(p1); + reg3 = readb(p3); + if (enable) { + reg1 |= SMB_CONFIG1_ENAB | SMB_CONFIG1_FEN; + reg3 |= SMB_CONFIG3_ENMI | SMB_CONFIG3_ENIDI; + } else { + reg1 &= ~(SMB_CONFIG1_ENAB | SMB_CONFIG1_FEN); + reg3 &= ~(SMB_CONFIG3_ENMI | SMB_CONFIG3_ENIDI); + } + + writeb(reg1, p1); + writeb(reg3, p3); +} + +static void pci1xxxx_i2c_set_freq(struct pci1xxxx_i2c *i2c) +{ + void __iomem *bp = i2c->i2c_base; + void __iomem *p_idle_scaling = bp + SMB_CORE_IDLE_SCALING_REG_OFF; + void __iomem *p_data_timing = bp + SMB_CORE_DATA_TIMING_REG_OFF; + void __iomem *p_hold_time = bp + SMB_CORE_SR_HOLD_TIME_REG_OFF; + void __iomem *p_to_scaling = bp + SMB_CORE_TO_SCALING_REG_OFF; + void __iomem *p_clk_sync = bp + SMB_CORE_CLK_SYNC_REG_OFF; + void __iomem *p_clk_reg = bp + SMB_CORE_BUS_CLK_REG_OFF; + + switch (i2c->freq) { + case I2C_MAX_STANDARD_MODE_FREQ: + writeb(SR_HOLD_TIME_100K_TICKS, p_hold_time); + writel(SMB_IDLE_SCALING_100K, p_idle_scaling); + writew(BUS_CLK_100K, p_clk_reg); + writel(CLK_SYNC_100K, p_clk_sync); + writel(DATA_TIMING_100K, p_data_timing); + writel(TO_SCALING_100K, p_to_scaling); + break; + + case I2C_MAX_FAST_MODE_PLUS_FREQ: + writeb(SR_HOLD_TIME_1000K_TICKS, p_hold_time); + writel(SMB_IDLE_SCALING_1000K, p_idle_scaling); + writew(BUS_CLK_1000K, p_clk_reg); + writel(CLK_SYNC_1000K, p_clk_sync); + writel(DATA_TIMING_1000K, p_data_timing); + writel(TO_SCALING_1000K, p_to_scaling); + break; + + case I2C_MAX_FAST_MODE_FREQ: + default: + writeb(SR_HOLD_TIME_400K_TICKS, p_hold_time); + writel(SMB_IDLE_SCALING_400K, p_idle_scaling); + writew(BUS_CLK_400K, p_clk_reg); + writel(CLK_SYNC_400K, p_clk_sync); + writel(DATA_TIMING_400K, p_data_timing); + writel(TO_SCALING_400K, p_to_scaling); + break; + } +} + +static void pci1xxxx_i2c_init(struct pci1xxxx_i2c *i2c) +{ + void __iomem *p2 = i2c->i2c_base + SMBUS_STATUS_REG_OFF; + void __iomem *p1 = i2c->i2c_base + SMB_GPR_REG; + u8 regval; + int ret; + + ret = set_sys_lock(i2c); + if (ret == -EPERM) { + /* + * Configure I2C Fast Mode as default frequency if unable + * to acquire sys lock. + */ + regval = 0; + } else { + regval = readl(p1); + release_sys_lock(i2c); + } + + switch (regval) { + case 0: + i2c->freq = I2C_MAX_FAST_MODE_FREQ; + pci1xxxx_i2c_set_freq(i2c); + break; + case 1: + i2c->freq = I2C_MAX_STANDARD_MODE_FREQ; + pci1xxxx_i2c_set_freq(i2c); + break; + case 2: + i2c->freq = I2C_MAX_FAST_MODE_PLUS_FREQ; + pci1xxxx_i2c_set_freq(i2c); + break; + case 3: + default: + break; + } + + pci1xxxx_i2c_config_padctrl(i2c, true); + i2c->flags |= I2C_FLAGS_DIRECT_MODE; + pci1xxxx_i2c_set_mode(i2c); + + /* + * Added as a precaution since BUF_EMPTY in status register + * also trigered an Interrupt. + */ + writeb(STA_BUF_EMPTY, p2); + + /* Configure core I2c control registers. */ + pci1xxxx_i2c_configure_core_reg(i2c, true); + + /* + * Enable pull-up for the SMB alert pin which is just used for + * wakeup right now. + */ + pci1xxxx_i2c_configure_smbalert_pin(i2c, true); +} + +static void pci1xxxx_i2c_clear_flags(struct pci1xxxx_i2c *i2c) +{ + u8 regval; + + /* Reset the internal buffer counters. */ + pci1xxxx_i2c_reset_counters(i2c); + + /* Clear low level interrupts. */ + regval = COMPLETION_MNAKX | COMPLETION_IDLE | COMPLETION_MDONE; + writeb(regval, i2c->i2c_base + SMB_CORE_COMPLETION_REG_OFF3); + reinit_completion(&i2c->i2c_xfer_done); + pci1xxxx_ack_nw_layer_intr(i2c, ALL_NW_LAYER_INTERRUPTS); + pci1xxxx_ack_high_level_intr(i2c, ALL_HIGH_LAYER_INTR); +} + +static int pci1xxxx_i2c_read(struct pci1xxxx_i2c *i2c, u8 slaveaddr, + unsigned char *buf, u16 total_len) +{ + void __iomem *p2 = i2c->i2c_base + SMB_CORE_COMPLETION_REG_OFF3; + void __iomem *p1 = i2c->i2c_base + SMB_CORE_CMD_REG_OFF1; + void __iomem *p3 = i2c->i2c_base + SMBUS_MST_BUF; + unsigned long time_left; + u16 remainingbytes; + u8 transferlen; + int retval = 0; + u8 read_count; + u32 regval; + u16 count; + + /* Enable I2C host controller by setting the ESO bit in the CONTROL REG. */ + pci1xxxx_i2c_enable_ESO(i2c); + pci1xxxx_i2c_clear_flags(i2c); + pci1xxxx_config_nw_layer_intr(i2c, INTR_MSK_DMA_TERM, true); + pci1xxxx_i2c_config_high_level_intr(i2c, I2C_BUF_MSTR_INTR_MASK, true); + + /* + * The I2C transfer could be more than 128 bytes. Our Core is + * capable of only sending 128 at a time. + * As far as the I2C read is concerned, initailly send the + * read slave address along with the number of bytes to read in + * ReadCount. After sending the slave address the interrupt + * is generated. On seeing the ACK for the slave address, reverse the + * buffer direction and run the DMA to initiate Read from slave. + */ + for (count = 0; count < total_len; count += transferlen) { + + /* + * Before start of any transaction clear the existing + * START/STOP conditions. + */ + writeb(0, p1); + remainingbytes = total_len - count; + transferlen = min_t(u16, remainingbytes, SMBUS_BUF_MAX_SIZE); + + /* + * Send STOP bit for the last chunk in the transaction. + * For I2C read transaction of more than BUF_SIZE, NACK should + * only be sent for the last read. + * Hence a bit FW_ACK is set for all the read chunks except for + * the last chunk. For the last chunk NACK should be sent and + * FW_ACK is cleared Send STOP only when I2C_FLAGS_STOP bit is + * set in the flags and only for the last transaction. + */ + if ((count + transferlen >= total_len) && + (i2c->flags & I2C_FLAGS_STOP)) { + pci1xxxx_i2c_set_clear_FW_ACK(i2c, false); + pci1xxxx_i2c_send_start_stop(i2c, 0); + } else { + pci1xxxx_i2c_set_clear_FW_ACK(i2c, true); + } + + /* Send START bit for the first transaction. */ + if (count == 0) { + pci1xxxx_i2c_set_transfer_dir(i2c, I2C_DIRN_WRITE); + pci1xxxx_i2c_send_start_stop(i2c, 1); + + /* Write I2c buffer with just the slave addr. */ + pci1xxxx_i2c_buffer_write(i2c, slaveaddr, 0, NULL); + + /* Set the count. Readcount is the transfer bytes. */ + pci1xxxx_i2c_set_count(i2c, 1, 1, transferlen); + + /* + * Set the Auto_start_read bit so that the HW itself + * will take care of the read phase. + */ + pci1xxxx_i2c_config_asr(i2c, true); + if (i2c->flags & I2C_FLAGS_SMB_BLK_READ) + pci1xxxx_i2c_set_readm(i2c, true); + } else { + pci1xxxx_i2c_set_count(i2c, 0, 0, transferlen); + pci1xxxx_i2c_config_asr(i2c, false); + pci1xxxx_i2c_clear_flags(i2c); + pci1xxxx_i2c_set_transfer_dir(i2c, I2C_DIRN_READ); + } + + /* Start the DMA. */ + pci1xxxx_i2c_start_DMA(i2c); + + /* Wait for the DMA_TERM interrupt. */ + time_left = wait_for_completion_timeout(&i2c->i2c_xfer_done, + msecs_to_jiffies(PCI1XXXX_I2C_TIMEOUT_MS)); + if (time_left == 0) { + /* Reset the I2C core to release the bus lock. */ + pci1xxxx_i2c_init(i2c); + retval = -ETIMEDOUT; + goto cleanup; + } + + /* Read the completion reg to know the reason for DMA_TERM. */ + regval = readb(p2); + + /* Slave did not respond. */ + if (regval & COMPLETION_MNAKX) { + writeb(COMPLETION_MNAKX, p2); + retval = -ETIMEDOUT; + goto cleanup; + } + + if (i2c->flags & I2C_FLAGS_SMB_BLK_READ) { + buf[0] = readb(p3); + read_count = buf[0]; + memcpy_fromio(&buf[1], p3 + 1, read_count); + } else { + memcpy_fromio(&buf[count], p3, transferlen); + } + } + +cleanup: + /* Disable all the interrupts. */ + pci1xxxx_config_nw_layer_intr(i2c, INTR_MSK_DMA_TERM, false); + pci1xxxx_i2c_config_high_level_intr(i2c, I2C_BUF_MSTR_INTR_MASK, false); + pci1xxxx_i2c_config_asr(i2c, false); + return retval; +} + +static int pci1xxxx_i2c_write(struct pci1xxxx_i2c *i2c, u8 slaveaddr, + unsigned char *buf, u16 total_len) +{ + void __iomem *p2 = i2c->i2c_base + SMB_CORE_COMPLETION_REG_OFF3; + void __iomem *p1 = i2c->i2c_base + SMB_CORE_CMD_REG_OFF1; + unsigned long time_left; + u16 remainingbytes; + u8 actualwritelen; + u8 transferlen; + int retval = 0; + u32 regval; + u16 count; + + /* Enable I2C host controller by setting the ESO bit in the CONTROL REG. */ + pci1xxxx_i2c_enable_ESO(i2c); + + /* Set the Buffer direction. */ + pci1xxxx_i2c_set_transfer_dir(i2c, I2C_DIRN_WRITE); + pci1xxxx_config_nw_layer_intr(i2c, INTR_MSK_DMA_TERM, true); + pci1xxxx_i2c_config_high_level_intr(i2c, I2C_BUF_MSTR_INTR_MASK, true); + + /* + * The i2c transfer could be more than 128 bytes. Our Core is + * capable of only sending 128 at a time. + */ + for (count = 0; count < total_len; count += transferlen) { + /* + * Before start of any transaction clear the existing + * START/STOP conditions. + */ + writeb(0, p1); + pci1xxxx_i2c_clear_flags(i2c); + remainingbytes = total_len - count; + + /* If it is the starting of the transaction send START. */ + if (count == 0) { + pci1xxxx_i2c_send_start_stop(i2c, 1); + + /* -1 for the slave address. */ + transferlen = min_t(u16, SMBUS_BUF_MAX_SIZE - 1, + remainingbytes); + pci1xxxx_i2c_buffer_write(i2c, slaveaddr, + transferlen, &buf[count]); + /* + * The actual number of bytes written on the I2C bus + * is including the slave address. + */ + actualwritelen = transferlen + 1; + } else { + transferlen = min_t(u16, SMBUS_BUF_MAX_SIZE, remainingbytes); + pci1xxxx_i2c_buffer_write(i2c, 0, transferlen, &buf[count]); + actualwritelen = transferlen; + } + + pci1xxxx_i2c_set_count(i2c, actualwritelen, actualwritelen, 0); + + /* + * Send STOP only when I2C_FLAGS_STOP bit is set in the flags and + * only for the last transaction. + */ + if (remainingbytes <= transferlen && + (i2c->flags & I2C_FLAGS_STOP)) + pci1xxxx_i2c_send_start_stop(i2c, 0); + + pci1xxxx_i2c_start_DMA(i2c); + + /* + * Wait for the DMA_TERM interrupt. + */ + time_left = wait_for_completion_timeout(&i2c->i2c_xfer_done, + msecs_to_jiffies(PCI1XXXX_I2C_TIMEOUT_MS)); + if (time_left == 0) { + /* Reset the I2C core to release the bus lock. */ + pci1xxxx_i2c_init(i2c); + retval = -ETIMEDOUT; + goto cleanup; + } + + regval = readb(p2); + if (regval & COMPLETION_MNAKX) { + writeb(COMPLETION_MNAKX, p2); + retval = -ETIMEDOUT; + goto cleanup; + } + } +cleanup: + /* Disable all the interrupts. */ + pci1xxxx_config_nw_layer_intr(i2c, INTR_MSK_DMA_TERM, false); + pci1xxxx_i2c_config_high_level_intr(i2c, I2C_BUF_MSTR_INTR_MASK, false); + + return retval; +} + +static int pci1xxxx_i2c_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct pci1xxxx_i2c *i2c = i2c_get_adapdata(adap); + u8 slaveaddr; + int retval; + u32 i; + + i2c->i2c_xfer_in_progress = true; + for (i = 0; i < num; i++) { + slaveaddr = i2c_8bit_addr_from_msg(&msgs[i]); + + /* + * Send the STOP bit if the transfer is the final one or + * if the I2C_M_STOP flag is set. + */ + if ((i == num - 1) || (msgs[i].flags & I2C_M_STOP)) + i2c->flags |= I2C_FLAGS_STOP; + else + i2c->flags &= ~I2C_FLAGS_STOP; + + if (msgs[i].flags & I2C_M_RECV_LEN) + i2c->flags |= I2C_FLAGS_SMB_BLK_READ; + else + i2c->flags &= ~I2C_FLAGS_SMB_BLK_READ; + + if (msgs[i].flags & I2C_M_RD) + retval = pci1xxxx_i2c_read(i2c, slaveaddr, + msgs[i].buf, msgs[i].len); + else + retval = pci1xxxx_i2c_write(i2c, slaveaddr, + msgs[i].buf, msgs[i].len); + + if (retval < 0) + break; + } + i2c->i2c_xfer_in_progress = false; + + if (retval < 0) + return retval; + + return num; +} + +/* + * List of supported functions by the driver. + */ +static u32 pci1xxxx_i2c_get_funcs(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_PROTOCOL_MANGLING | + I2C_FUNC_SMBUS_BLOCK_PROC_CALL | + I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_PROC_CALL | + I2C_FUNC_SMBUS_BLOCK_DATA; +} + +static const struct i2c_algorithm pci1xxxx_i2c_algo = { + .master_xfer = pci1xxxx_i2c_xfer, + .functionality = pci1xxxx_i2c_get_funcs, +}; + +static const struct i2c_adapter_quirks pci1xxxx_i2c_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN, +}; + +static const struct i2c_adapter pci1xxxx_i2c_ops = { + .owner = THIS_MODULE, + .name = "PCI1xxxx I2C Adapter", + .algo = &pci1xxxx_i2c_algo, + .quirks = &pci1xxxx_i2c_quirks, +}; + +static int pci1xxxx_i2c_suspend(struct device *dev) +{ + struct pci1xxxx_i2c *i2c = dev_get_drvdata(dev); + void __iomem *p = i2c->i2c_base + SMBUS_RESET_REG; + struct pci_dev *pdev = to_pci_dev(dev); + u32 regval; + + i2c_mark_adapter_suspended(&i2c->adap); + + /* + * If the system is put into 'suspend' state when the I2C transfer is in + * progress, wait until the transfer completes. + */ + while (i2c->i2c_xfer_in_progress) + msleep(20); + + pci1xxxx_i2c_config_high_level_intr(i2c, SMBALERT_WAKE_INTR_MASK, true); + + /* + * Enable the PERST_DIS bit to mask the PERST from resetting the core + * registers. + */ + regval = readl(p); + regval |= PERI_SMBUS_D3_RESET_DIS; + writel(regval, p); + + /* Enable PCI wake in the PMCSR register. */ + device_set_wakeup_enable(dev, true); + pci_wake_from_d3(pdev, true); + + return 0; +} + +static int pci1xxxx_i2c_resume(struct device *dev) +{ + struct pci1xxxx_i2c *i2c = dev_get_drvdata(dev); + void __iomem *p1 = i2c->i2c_base + SMBUS_GEN_INT_STAT_REG_OFF; + void __iomem *p2 = i2c->i2c_base + SMBUS_RESET_REG; + struct pci_dev *pdev = to_pci_dev(dev); + u32 regval; + + regval = readw(p1); + writew(regval, p1); + pci1xxxx_i2c_config_high_level_intr(i2c, SMBALERT_WAKE_INTR_MASK, false); + regval = readl(p2); + regval &= ~PERI_SMBUS_D3_RESET_DIS; + writel(regval, p2); + i2c_mark_adapter_resumed(&i2c->adap); + pci_wake_from_d3(pdev, false); + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(pci1xxxx_i2c_pm_ops, pci1xxxx_i2c_suspend, + pci1xxxx_i2c_resume); + +static void pci1xxxx_i2c_shutdown(void *data) +{ + struct pci1xxxx_i2c *i2c = data; + + pci1xxxx_i2c_config_padctrl(i2c, false); + pci1xxxx_i2c_configure_core_reg(i2c, false); +} + +static int pci1xxxx_i2c_probe_pci(struct pci_dev *pdev, + const struct pci_device_id *ent) +{ + struct device *dev = &pdev->dev; + struct pci1xxxx_i2c *i2c; + int ret; + + i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + pci_set_drvdata(pdev, i2c); + i2c->i2c_xfer_in_progress = false; + + ret = pcim_enable_device(pdev); + if (ret) + return ret; + + pci_set_master(pdev); + + /* + * We are getting the base address of the SMB core. SMB core uses + * BAR0 and size is 32K. + */ + ret = pcim_iomap_regions(pdev, BIT(0), pci_name(pdev)); + if (ret < 0) + return ret; + + i2c->i2c_base = pcim_iomap_table(pdev)[0]; + init_completion(&i2c->i2c_xfer_done); + pci1xxxx_i2c_init(i2c); + + ret = devm_add_action(dev, pci1xxxx_i2c_shutdown, i2c); + if (ret) + return ret; + + ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES); + if (ret < 0) + return ret; + + ret = devm_request_irq(dev, pci_irq_vector(pdev, 0), pci1xxxx_i2c_isr, + 0, pci_name(pdev), i2c); + if (ret) + return ret; + + i2c->adap = pci1xxxx_i2c_ops; + i2c->adap.dev.parent = dev; + + snprintf(i2c->adap.name, sizeof(i2c->adap.name), + "MCHP PCI1xxxx i2c adapter at %s", pci_name(pdev)); + + i2c_set_adapdata(&i2c->adap, i2c); + + ret = devm_i2c_add_adapter(dev, &i2c->adap); + if (ret) + return dev_err_probe(dev, ret, "i2c add adapter failed\n"); + + return 0; +} + +static const struct pci_device_id pci1xxxx_i2c_pci_id_table[] = { + { PCI_VDEVICE(EFAR, 0xA003) }, + { PCI_VDEVICE(EFAR, 0xA013) }, + { PCI_VDEVICE(EFAR, 0xA023) }, + { PCI_VDEVICE(EFAR, 0xA033) }, + { PCI_VDEVICE(EFAR, 0xA043) }, + { } +}; +MODULE_DEVICE_TABLE(pci, pci1xxxx_i2c_pci_id_table); + +static struct pci_driver pci1xxxx_i2c_pci_driver = { + .name = "i2c-mchp-pci1xxxx", + .id_table = pci1xxxx_i2c_pci_id_table, + .probe = pci1xxxx_i2c_probe_pci, + .driver = { + .pm = pm_sleep_ptr(&pci1xxxx_i2c_pm_ops), + }, +}; +module_pci_driver(pci1xxxx_i2c_pci_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Tharun Kumar P<tharunkumar.pasumarthi@microchip.com>"); +MODULE_AUTHOR("Kumaravel Thiagarajan <kumaravel.thiagarajan@microchip.com>"); +MODULE_DESCRIPTION("Microchip Technology Inc. pci1xxxx I2C bus driver"); diff --git a/drivers/i2c/busses/i2c-meson.c b/drivers/i2c/busses/i2c-meson.c new file mode 100644 index 000000000..c7b203cc4 --- /dev/null +++ b/drivers/i2c/busses/i2c-meson.c @@ -0,0 +1,579 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * I2C bus driver for Amlogic Meson SoCs + * + * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com> + */ + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/types.h> + +/* Meson I2C register map */ +#define REG_CTRL 0x00 +#define REG_SLAVE_ADDR 0x04 +#define REG_TOK_LIST0 0x08 +#define REG_TOK_LIST1 0x0c +#define REG_TOK_WDATA0 0x10 +#define REG_TOK_WDATA1 0x14 +#define REG_TOK_RDATA0 0x18 +#define REG_TOK_RDATA1 0x1c + +/* Control register fields */ +#define REG_CTRL_START BIT(0) +#define REG_CTRL_ACK_IGNORE BIT(1) +#define REG_CTRL_STATUS BIT(2) +#define REG_CTRL_ERROR BIT(3) +#define REG_CTRL_CLKDIV_SHIFT 12 +#define REG_CTRL_CLKDIV_MASK GENMASK(21, REG_CTRL_CLKDIV_SHIFT) +#define REG_CTRL_CLKDIVEXT_SHIFT 28 +#define REG_CTRL_CLKDIVEXT_MASK GENMASK(29, REG_CTRL_CLKDIVEXT_SHIFT) + +#define REG_SLV_ADDR_MASK GENMASK(7, 0) +#define REG_SLV_SDA_FILTER_MASK GENMASK(10, 8) +#define REG_SLV_SCL_FILTER_MASK GENMASK(13, 11) +#define REG_SLV_SCL_LOW_SHIFT 16 +#define REG_SLV_SCL_LOW_MASK GENMASK(27, REG_SLV_SCL_LOW_SHIFT) +#define REG_SLV_SCL_LOW_EN BIT(28) + +#define I2C_TIMEOUT_MS 500 +#define FILTER_DELAY 15 + +enum { + TOKEN_END = 0, + TOKEN_START, + TOKEN_SLAVE_ADDR_WRITE, + TOKEN_SLAVE_ADDR_READ, + TOKEN_DATA, + TOKEN_DATA_LAST, + TOKEN_STOP, +}; + +enum { + STATE_IDLE, + STATE_READ, + STATE_WRITE, +}; + +/** + * struct meson_i2c - Meson I2C device private data + * + * @adap: I2C adapter instance + * @dev: Pointer to device structure + * @regs: Base address of the device memory mapped registers + * @clk: Pointer to clock structure + * @msg: Pointer to the current I2C message + * @state: Current state in the driver state machine + * @last: Flag set for the last message in the transfer + * @count: Number of bytes to be sent/received in current transfer + * @pos: Current position in the send/receive buffer + * @error: Flag set when an error is received + * @lock: To avoid race conditions between irq handler and xfer code + * @done: Completion used to wait for transfer termination + * @tokens: Sequence of tokens to be written to the device + * @num_tokens: Number of tokens + * @data: Pointer to the controller's platform data + */ +struct meson_i2c { + struct i2c_adapter adap; + struct device *dev; + void __iomem *regs; + struct clk *clk; + + struct i2c_msg *msg; + int state; + bool last; + int count; + int pos; + int error; + + spinlock_t lock; + struct completion done; + u32 tokens[2]; + int num_tokens; + + const struct meson_i2c_data *data; +}; + +struct meson_i2c_data { + void (*set_clk_div)(struct meson_i2c *i2c, unsigned int freq); +}; + +static void meson_i2c_set_mask(struct meson_i2c *i2c, int reg, u32 mask, + u32 val) +{ + u32 data; + + data = readl(i2c->regs + reg); + data &= ~mask; + data |= val & mask; + writel(data, i2c->regs + reg); +} + +static void meson_i2c_reset_tokens(struct meson_i2c *i2c) +{ + i2c->tokens[0] = 0; + i2c->tokens[1] = 0; + i2c->num_tokens = 0; +} + +static void meson_i2c_add_token(struct meson_i2c *i2c, int token) +{ + if (i2c->num_tokens < 8) + i2c->tokens[0] |= (token & 0xf) << (i2c->num_tokens * 4); + else + i2c->tokens[1] |= (token & 0xf) << ((i2c->num_tokens % 8) * 4); + + i2c->num_tokens++; +} + +static void meson_gxbb_axg_i2c_set_clk_div(struct meson_i2c *i2c, unsigned int freq) +{ + unsigned long clk_rate = clk_get_rate(i2c->clk); + unsigned int div_h, div_l; + + /* According to I2C-BUS Spec 2.1, in FAST-MODE, the minimum LOW period is 1.3uS, and + * minimum HIGH is least 0.6us. + * For 400000 freq, the period is 2.5us. To keep within the specs, give 40% of period to + * HIGH and 60% to LOW. This means HIGH at 1.0us and LOW 1.5us. + * The same applies for Fast-mode plus, where LOW is 0.5us and HIGH is 0.26us. + * Duty = H/(H + L) = 2/5 + */ + if (freq <= I2C_MAX_STANDARD_MODE_FREQ) { + div_h = DIV_ROUND_UP(clk_rate, freq); + div_l = DIV_ROUND_UP(div_h, 4); + div_h = DIV_ROUND_UP(div_h, 2) - FILTER_DELAY; + } else { + div_h = DIV_ROUND_UP(clk_rate * 2, freq * 5) - FILTER_DELAY; + div_l = DIV_ROUND_UP(clk_rate * 3, freq * 5 * 2); + } + + /* clock divider has 12 bits */ + if (div_h > GENMASK(11, 0)) { + dev_err(i2c->dev, "requested bus frequency too low\n"); + div_h = GENMASK(11, 0); + } + if (div_l > GENMASK(11, 0)) { + dev_err(i2c->dev, "requested bus frequency too low\n"); + div_l = GENMASK(11, 0); + } + + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_CLKDIV_MASK, + FIELD_PREP(REG_CTRL_CLKDIV_MASK, div_h & GENMASK(9, 0))); + + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_CLKDIVEXT_MASK, + FIELD_PREP(REG_CTRL_CLKDIVEXT_MASK, div_h >> 10)); + + /* set SCL low delay */ + meson_i2c_set_mask(i2c, REG_SLAVE_ADDR, REG_SLV_SCL_LOW_MASK, + FIELD_PREP(REG_SLV_SCL_LOW_MASK, div_l)); + + /* Enable HIGH/LOW mode */ + meson_i2c_set_mask(i2c, REG_SLAVE_ADDR, REG_SLV_SCL_LOW_EN, REG_SLV_SCL_LOW_EN); + + dev_dbg(i2c->dev, "%s: clk %lu, freq %u, divh %u, divl %u\n", __func__, + clk_rate, freq, div_h, div_l); +} + +static void meson6_i2c_set_clk_div(struct meson_i2c *i2c, unsigned int freq) +{ + unsigned long clk_rate = clk_get_rate(i2c->clk); + unsigned int div; + + div = DIV_ROUND_UP(clk_rate, freq); + div -= FILTER_DELAY; + div = DIV_ROUND_UP(div, 4); + + /* clock divider has 12 bits */ + if (div > GENMASK(11, 0)) { + dev_err(i2c->dev, "requested bus frequency too low\n"); + div = GENMASK(11, 0); + } + + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_CLKDIV_MASK, + FIELD_PREP(REG_CTRL_CLKDIV_MASK, div & GENMASK(9, 0))); + + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_CLKDIVEXT_MASK, + FIELD_PREP(REG_CTRL_CLKDIVEXT_MASK, div >> 10)); + + /* Disable HIGH/LOW mode */ + meson_i2c_set_mask(i2c, REG_SLAVE_ADDR, REG_SLV_SCL_LOW_EN, 0); + + dev_dbg(i2c->dev, "%s: clk %lu, freq %u, div %u\n", __func__, + clk_rate, freq, div); +} + +static void meson_i2c_get_data(struct meson_i2c *i2c, char *buf, int len) +{ + u32 rdata0, rdata1; + int i; + + rdata0 = readl(i2c->regs + REG_TOK_RDATA0); + rdata1 = readl(i2c->regs + REG_TOK_RDATA1); + + dev_dbg(i2c->dev, "%s: data %08x %08x len %d\n", __func__, + rdata0, rdata1, len); + + for (i = 0; i < min(4, len); i++) + *buf++ = (rdata0 >> i * 8) & 0xff; + + for (i = 4; i < min(8, len); i++) + *buf++ = (rdata1 >> (i - 4) * 8) & 0xff; +} + +static void meson_i2c_put_data(struct meson_i2c *i2c, char *buf, int len) +{ + u32 wdata0 = 0, wdata1 = 0; + int i; + + for (i = 0; i < min(4, len); i++) + wdata0 |= *buf++ << (i * 8); + + for (i = 4; i < min(8, len); i++) + wdata1 |= *buf++ << ((i - 4) * 8); + + writel(wdata0, i2c->regs + REG_TOK_WDATA0); + writel(wdata1, i2c->regs + REG_TOK_WDATA1); + + dev_dbg(i2c->dev, "%s: data %08x %08x len %d\n", __func__, + wdata0, wdata1, len); +} + +static void meson_i2c_prepare_xfer(struct meson_i2c *i2c) +{ + bool write = !(i2c->msg->flags & I2C_M_RD); + int i; + + i2c->count = min(i2c->msg->len - i2c->pos, 8); + + for (i = 0; i < i2c->count - 1; i++) + meson_i2c_add_token(i2c, TOKEN_DATA); + + if (i2c->count) { + if (write || i2c->pos + i2c->count < i2c->msg->len) + meson_i2c_add_token(i2c, TOKEN_DATA); + else + meson_i2c_add_token(i2c, TOKEN_DATA_LAST); + } + + if (write) + meson_i2c_put_data(i2c, i2c->msg->buf + i2c->pos, i2c->count); + + if (i2c->last && i2c->pos + i2c->count >= i2c->msg->len) + meson_i2c_add_token(i2c, TOKEN_STOP); + + writel(i2c->tokens[0], i2c->regs + REG_TOK_LIST0); + writel(i2c->tokens[1], i2c->regs + REG_TOK_LIST1); +} + +static void meson_i2c_transfer_complete(struct meson_i2c *i2c, u32 ctrl) +{ + if (ctrl & REG_CTRL_ERROR) { + /* + * The bit is set when the IGNORE_NAK bit is cleared + * and the device didn't respond. In this case, the + * I2C controller automatically generates a STOP + * condition. + */ + dev_dbg(i2c->dev, "error bit set\n"); + i2c->error = -ENXIO; + i2c->state = STATE_IDLE; + } else { + if (i2c->state == STATE_READ && i2c->count) + meson_i2c_get_data(i2c, i2c->msg->buf + i2c->pos, + i2c->count); + + i2c->pos += i2c->count; + + if (i2c->pos >= i2c->msg->len) + i2c->state = STATE_IDLE; + } +} + +static irqreturn_t meson_i2c_irq(int irqno, void *dev_id) +{ + struct meson_i2c *i2c = dev_id; + unsigned int ctrl; + + spin_lock(&i2c->lock); + + meson_i2c_reset_tokens(i2c); + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, 0); + ctrl = readl(i2c->regs + REG_CTRL); + + dev_dbg(i2c->dev, "irq: state %d, pos %d, count %d, ctrl %08x\n", + i2c->state, i2c->pos, i2c->count, ctrl); + + if (i2c->state == STATE_IDLE) { + spin_unlock(&i2c->lock); + return IRQ_NONE; + } + + meson_i2c_transfer_complete(i2c, ctrl); + + if (i2c->state == STATE_IDLE) { + complete(&i2c->done); + goto out; + } + + /* Restart the processing */ + meson_i2c_prepare_xfer(i2c); + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, REG_CTRL_START); +out: + spin_unlock(&i2c->lock); + + return IRQ_HANDLED; +} + +static void meson_i2c_do_start(struct meson_i2c *i2c, struct i2c_msg *msg) +{ + int token; + + token = (msg->flags & I2C_M_RD) ? TOKEN_SLAVE_ADDR_READ : + TOKEN_SLAVE_ADDR_WRITE; + + + meson_i2c_set_mask(i2c, REG_SLAVE_ADDR, REG_SLV_ADDR_MASK, + FIELD_PREP(REG_SLV_ADDR_MASK, msg->addr << 1)); + + meson_i2c_add_token(i2c, TOKEN_START); + meson_i2c_add_token(i2c, token); +} + +static int meson_i2c_xfer_msg(struct meson_i2c *i2c, struct i2c_msg *msg, + int last, bool atomic) +{ + unsigned long time_left, flags; + int ret = 0; + u32 ctrl; + + i2c->msg = msg; + i2c->last = last; + i2c->pos = 0; + i2c->count = 0; + i2c->error = 0; + + meson_i2c_reset_tokens(i2c); + + flags = (msg->flags & I2C_M_IGNORE_NAK) ? REG_CTRL_ACK_IGNORE : 0; + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_ACK_IGNORE, flags); + + if (!(msg->flags & I2C_M_NOSTART)) + meson_i2c_do_start(i2c, msg); + + i2c->state = (msg->flags & I2C_M_RD) ? STATE_READ : STATE_WRITE; + meson_i2c_prepare_xfer(i2c); + + if (!atomic) + reinit_completion(&i2c->done); + + /* Start the transfer */ + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, REG_CTRL_START); + + if (atomic) { + ret = readl_poll_timeout_atomic(i2c->regs + REG_CTRL, ctrl, + !(ctrl & REG_CTRL_STATUS), + 10, I2C_TIMEOUT_MS * 1000); + } else { + time_left = msecs_to_jiffies(I2C_TIMEOUT_MS); + time_left = wait_for_completion_timeout(&i2c->done, time_left); + + if (!time_left) + ret = -ETIMEDOUT; + } + + /* + * Protect access to i2c struct and registers from interrupt + * handlers triggered by a transfer terminated after the + * timeout period + */ + spin_lock_irqsave(&i2c->lock, flags); + + if (atomic && !ret) + meson_i2c_transfer_complete(i2c, ctrl); + + /* Abort any active operation */ + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, 0); + + if (ret) + i2c->state = STATE_IDLE; + + if (i2c->error) + ret = i2c->error; + + spin_unlock_irqrestore(&i2c->lock, flags); + + return ret; +} + +static int meson_i2c_xfer_messages(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num, bool atomic) +{ + struct meson_i2c *i2c = adap->algo_data; + int i, ret = 0; + + for (i = 0; i < num; i++) { + ret = meson_i2c_xfer_msg(i2c, msgs + i, i == num - 1, atomic); + if (ret) + break; + } + + return ret ?: i; +} + +static int meson_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + return meson_i2c_xfer_messages(adap, msgs, num, false); +} + +static int meson_i2c_xfer_atomic(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + return meson_i2c_xfer_messages(adap, msgs, num, true); +} + +static u32 meson_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm meson_i2c_algorithm = { + .master_xfer = meson_i2c_xfer, + .master_xfer_atomic = meson_i2c_xfer_atomic, + .functionality = meson_i2c_func, +}; + +static int meson_i2c_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct meson_i2c *i2c; + struct i2c_timings timings; + int irq, ret = 0; + + i2c = devm_kzalloc(&pdev->dev, sizeof(struct meson_i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c_parse_fw_timings(&pdev->dev, &timings, true); + + i2c->dev = &pdev->dev; + platform_set_drvdata(pdev, i2c); + + spin_lock_init(&i2c->lock); + init_completion(&i2c->done); + + i2c->data = (const struct meson_i2c_data *) + of_device_get_match_data(&pdev->dev); + + i2c->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(i2c->clk)) { + dev_err(&pdev->dev, "can't get device clock\n"); + return PTR_ERR(i2c->clk); + } + + i2c->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c->regs)) + return PTR_ERR(i2c->regs); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + ret = devm_request_irq(&pdev->dev, irq, meson_i2c_irq, 0, NULL, i2c); + if (ret < 0) { + dev_err(&pdev->dev, "can't request IRQ\n"); + return ret; + } + + ret = clk_prepare_enable(i2c->clk); + if (ret < 0) { + dev_err(&pdev->dev, "can't prepare clock\n"); + return ret; + } + + strscpy(i2c->adap.name, "Meson I2C adapter", + sizeof(i2c->adap.name)); + i2c->adap.owner = THIS_MODULE; + i2c->adap.algo = &meson_i2c_algorithm; + i2c->adap.dev.parent = &pdev->dev; + i2c->adap.dev.of_node = np; + i2c->adap.algo_data = i2c; + + /* + * A transfer is triggered when START bit changes from 0 to 1. + * Ensure that the bit is set to 0 after probe + */ + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, 0); + + /* Disable filtering */ + meson_i2c_set_mask(i2c, REG_SLAVE_ADDR, + REG_SLV_SDA_FILTER_MASK | REG_SLV_SCL_FILTER_MASK, 0); + + if (!i2c->data->set_clk_div) { + clk_disable_unprepare(i2c->clk); + return -EINVAL; + } + i2c->data->set_clk_div(i2c, timings.bus_freq_hz); + + ret = i2c_add_adapter(&i2c->adap); + if (ret < 0) { + clk_disable_unprepare(i2c->clk); + return ret; + } + + return 0; +} + +static void meson_i2c_remove(struct platform_device *pdev) +{ + struct meson_i2c *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adap); + clk_disable_unprepare(i2c->clk); +} + +static const struct meson_i2c_data i2c_meson6_data = { + .set_clk_div = meson6_i2c_set_clk_div, +}; + +static const struct meson_i2c_data i2c_gxbb_data = { + .set_clk_div = meson_gxbb_axg_i2c_set_clk_div, +}; + +static const struct meson_i2c_data i2c_axg_data = { + .set_clk_div = meson_gxbb_axg_i2c_set_clk_div, +}; + +static const struct of_device_id meson_i2c_match[] = { + { .compatible = "amlogic,meson6-i2c", .data = &i2c_meson6_data }, + { .compatible = "amlogic,meson-gxbb-i2c", .data = &i2c_gxbb_data }, + { .compatible = "amlogic,meson-axg-i2c", .data = &i2c_axg_data }, + {}, +}; + +MODULE_DEVICE_TABLE(of, meson_i2c_match); + +static struct platform_driver meson_i2c_driver = { + .probe = meson_i2c_probe, + .remove_new = meson_i2c_remove, + .driver = { + .name = "meson-i2c", + .of_match_table = meson_i2c_match, + }, +}; + +module_platform_driver(meson_i2c_driver); + +MODULE_DESCRIPTION("Amlogic Meson I2C Bus driver"); +MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-microchip-corei2c.c b/drivers/i2c/busses/i2c-microchip-corei2c.c new file mode 100644 index 000000000..0b0a1c4d1 --- /dev/null +++ b/drivers/i2c/busses/i2c-microchip-corei2c.c @@ -0,0 +1,477 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Microchip CoreI2C I2C controller driver + * + * Copyright (c) 2018-2022 Microchip Corporation. All rights reserved. + * + * Author: Daire McNamara <daire.mcnamara@microchip.com> + * Author: Conor Dooley <conor.dooley@microchip.com> + */ +#include <linux/clk.h> +#include <linux/clkdev.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +#define CORE_I2C_CTRL (0x00) +#define CTRL_CR0 BIT(0) +#define CTRL_CR1 BIT(1) +#define CTRL_AA BIT(2) +#define CTRL_SI BIT(3) +#define CTRL_STO BIT(4) +#define CTRL_STA BIT(5) +#define CTRL_ENS1 BIT(6) +#define CTRL_CR2 BIT(7) + +#define STATUS_BUS_ERROR (0x00) +#define STATUS_M_START_SENT (0x08) +#define STATUS_M_REPEATED_START_SENT (0x10) +#define STATUS_M_SLAW_ACK (0x18) +#define STATUS_M_SLAW_NACK (0x20) +#define STATUS_M_TX_DATA_ACK (0x28) +#define STATUS_M_TX_DATA_NACK (0x30) +#define STATUS_M_ARB_LOST (0x38) +#define STATUS_M_SLAR_ACK (0x40) +#define STATUS_M_SLAR_NACK (0x48) +#define STATUS_M_RX_DATA_ACKED (0x50) +#define STATUS_M_RX_DATA_NACKED (0x58) +#define STATUS_S_SLAW_ACKED (0x60) +#define STATUS_S_ARB_LOST_SLAW_ACKED (0x68) +#define STATUS_S_GENERAL_CALL_ACKED (0x70) +#define STATUS_S_ARB_LOST_GENERAL_CALL_ACKED (0x78) +#define STATUS_S_RX_DATA_ACKED (0x80) +#define STATUS_S_RX_DATA_NACKED (0x88) +#define STATUS_S_GENERAL_CALL_RX_DATA_ACKED (0x90) +#define STATUS_S_GENERAL_CALL_RX_DATA_NACKED (0x98) +#define STATUS_S_RX_STOP (0xA0) +#define STATUS_S_SLAR_ACKED (0xA8) +#define STATUS_S_ARB_LOST_SLAR_ACKED (0xB0) +#define STATUS_S_TX_DATA_ACK (0xB8) +#define STATUS_S_TX_DATA_NACK (0xC0) +#define STATUS_LAST_DATA_ACK (0xC8) +#define STATUS_M_SMB_MASTER_RESET (0xD0) +#define STATUS_S_SCL_LOW_TIMEOUT (0xD8) /* 25 ms */ +#define STATUS_NO_STATE_INFO (0xF8) + +#define CORE_I2C_STATUS (0x04) +#define CORE_I2C_DATA (0x08) +#define WRITE_BIT (0x0) +#define READ_BIT (0x1) +#define SLAVE_ADDR_SHIFT (1) +#define CORE_I2C_SLAVE0_ADDR (0x0c) +#define GENERAL_CALL_BIT (0x0) +#define CORE_I2C_SMBUS (0x10) +#define SMBALERT_INT_ENB (0x0) +#define SMBSUS_INT_ENB (0x1) +#define SMBUS_ENB (0x2) +#define SMBALERT_NI_STATUS (0x3) +#define SMBALERT_NO_CTRL (0x4) +#define SMBSUS_NI_STATUS (0x5) +#define SMBSUS_NO_CTRL (0x6) +#define SMBUS_RESET (0x7) +#define CORE_I2C_FREQ (0x14) +#define CORE_I2C_GLITCHREG (0x18) +#define CORE_I2C_SLAVE1_ADDR (0x1c) + +#define PCLK_DIV_960 (CTRL_CR2) +#define PCLK_DIV_256 (0) +#define PCLK_DIV_224 (CTRL_CR0) +#define PCLK_DIV_192 (CTRL_CR1) +#define PCLK_DIV_160 (CTRL_CR0 | CTRL_CR1) +#define PCLK_DIV_120 (CTRL_CR0 | CTRL_CR2) +#define PCLK_DIV_60 (CTRL_CR1 | CTRL_CR2) +#define BCLK_DIV_8 (CTRL_CR0 | CTRL_CR1 | CTRL_CR2) +#define CLK_MASK (CTRL_CR0 | CTRL_CR1 | CTRL_CR2) + +/** + * struct mchp_corei2c_dev - Microchip CoreI2C device private data + * + * @base: pointer to register struct + * @dev: device reference + * @i2c_clk: clock reference for i2c input clock + * @buf: pointer to msg buffer for easier use + * @msg_complete: xfer completion object + * @adapter: core i2c abstraction + * @msg_err: error code for completed message + * @bus_clk_rate: current i2c bus clock rate + * @isr_status: cached copy of local ISR status + * @msg_len: number of bytes transferred in msg + * @addr: address of the current slave + */ +struct mchp_corei2c_dev { + void __iomem *base; + struct device *dev; + struct clk *i2c_clk; + u8 *buf; + struct completion msg_complete; + struct i2c_adapter adapter; + int msg_err; + u32 bus_clk_rate; + u32 isr_status; + u16 msg_len; + u8 addr; +}; + +static void mchp_corei2c_core_disable(struct mchp_corei2c_dev *idev) +{ + u8 ctrl = readb(idev->base + CORE_I2C_CTRL); + + ctrl &= ~CTRL_ENS1; + writeb(ctrl, idev->base + CORE_I2C_CTRL); +} + +static void mchp_corei2c_core_enable(struct mchp_corei2c_dev *idev) +{ + u8 ctrl = readb(idev->base + CORE_I2C_CTRL); + + ctrl |= CTRL_ENS1; + writeb(ctrl, idev->base + CORE_I2C_CTRL); +} + +static void mchp_corei2c_reset(struct mchp_corei2c_dev *idev) +{ + mchp_corei2c_core_disable(idev); + mchp_corei2c_core_enable(idev); +} + +static inline void mchp_corei2c_stop(struct mchp_corei2c_dev *idev) +{ + u8 ctrl = readb(idev->base + CORE_I2C_CTRL); + + ctrl |= CTRL_STO; + writeb(ctrl, idev->base + CORE_I2C_CTRL); +} + +static inline int mchp_corei2c_set_divisor(u32 rate, + struct mchp_corei2c_dev *idev) +{ + u8 clkval, ctrl; + + if (rate >= 960) + clkval = PCLK_DIV_960; + else if (rate >= 256) + clkval = PCLK_DIV_256; + else if (rate >= 224) + clkval = PCLK_DIV_224; + else if (rate >= 192) + clkval = PCLK_DIV_192; + else if (rate >= 160) + clkval = PCLK_DIV_160; + else if (rate >= 120) + clkval = PCLK_DIV_120; + else if (rate >= 60) + clkval = PCLK_DIV_60; + else if (rate >= 8) + clkval = BCLK_DIV_8; + else + return -EINVAL; + + ctrl = readb(idev->base + CORE_I2C_CTRL); + ctrl &= ~CLK_MASK; + ctrl |= clkval; + writeb(ctrl, idev->base + CORE_I2C_CTRL); + + ctrl = readb(idev->base + CORE_I2C_CTRL); + if ((ctrl & CLK_MASK) != clkval) + return -EIO; + + return 0; +} + +static int mchp_corei2c_init(struct mchp_corei2c_dev *idev) +{ + u32 clk_rate = clk_get_rate(idev->i2c_clk); + u32 divisor = clk_rate / idev->bus_clk_rate; + int ret; + + ret = mchp_corei2c_set_divisor(divisor, idev); + if (ret) + return ret; + + mchp_corei2c_reset(idev); + + return 0; +} + +static void mchp_corei2c_empty_rx(struct mchp_corei2c_dev *idev) +{ + u8 ctrl; + + if (idev->msg_len > 0) { + *idev->buf++ = readb(idev->base + CORE_I2C_DATA); + idev->msg_len--; + } + + if (idev->msg_len <= 1) { + ctrl = readb(idev->base + CORE_I2C_CTRL); + ctrl &= ~CTRL_AA; + writeb(ctrl, idev->base + CORE_I2C_CTRL); + } +} + +static int mchp_corei2c_fill_tx(struct mchp_corei2c_dev *idev) +{ + if (idev->msg_len > 0) + writeb(*idev->buf++, idev->base + CORE_I2C_DATA); + idev->msg_len--; + + return 0; +} + +static irqreturn_t mchp_corei2c_handle_isr(struct mchp_corei2c_dev *idev) +{ + u32 status = idev->isr_status; + u8 ctrl; + bool last_byte = false, finished = false; + + if (!idev->buf) + return IRQ_NONE; + + switch (status) { + case STATUS_M_START_SENT: + case STATUS_M_REPEATED_START_SENT: + ctrl = readb(idev->base + CORE_I2C_CTRL); + ctrl &= ~CTRL_STA; + writeb(idev->addr, idev->base + CORE_I2C_DATA); + writeb(ctrl, idev->base + CORE_I2C_CTRL); + if (idev->msg_len == 0) + finished = true; + break; + case STATUS_M_ARB_LOST: + idev->msg_err = -EAGAIN; + finished = true; + break; + case STATUS_M_SLAW_ACK: + case STATUS_M_TX_DATA_ACK: + if (idev->msg_len > 0) + mchp_corei2c_fill_tx(idev); + else + last_byte = true; + break; + case STATUS_M_TX_DATA_NACK: + case STATUS_M_SLAR_NACK: + case STATUS_M_SLAW_NACK: + idev->msg_err = -ENXIO; + last_byte = true; + break; + case STATUS_M_SLAR_ACK: + ctrl = readb(idev->base + CORE_I2C_CTRL); + if (idev->msg_len == 1u) { + ctrl &= ~CTRL_AA; + writeb(ctrl, idev->base + CORE_I2C_CTRL); + } else { + ctrl |= CTRL_AA; + writeb(ctrl, idev->base + CORE_I2C_CTRL); + } + if (idev->msg_len < 1u) + last_byte = true; + break; + case STATUS_M_RX_DATA_ACKED: + mchp_corei2c_empty_rx(idev); + break; + case STATUS_M_RX_DATA_NACKED: + mchp_corei2c_empty_rx(idev); + if (idev->msg_len == 0) + last_byte = true; + break; + default: + break; + } + + /* On the last byte to be transmitted, send STOP */ + if (last_byte) + mchp_corei2c_stop(idev); + + if (last_byte || finished) + complete(&idev->msg_complete); + + return IRQ_HANDLED; +} + +static irqreturn_t mchp_corei2c_isr(int irq, void *_dev) +{ + struct mchp_corei2c_dev *idev = _dev; + irqreturn_t ret = IRQ_NONE; + u8 ctrl; + + ctrl = readb(idev->base + CORE_I2C_CTRL); + if (ctrl & CTRL_SI) { + idev->isr_status = readb(idev->base + CORE_I2C_STATUS); + ret = mchp_corei2c_handle_isr(idev); + } + + ctrl = readb(idev->base + CORE_I2C_CTRL); + ctrl &= ~CTRL_SI; + writeb(ctrl, idev->base + CORE_I2C_CTRL); + + return ret; +} + +static int mchp_corei2c_xfer_msg(struct mchp_corei2c_dev *idev, + struct i2c_msg *msg) +{ + u8 ctrl; + unsigned long time_left; + + idev->addr = i2c_8bit_addr_from_msg(msg); + idev->msg_len = msg->len; + idev->buf = msg->buf; + idev->msg_err = 0; + + reinit_completion(&idev->msg_complete); + + mchp_corei2c_core_enable(idev); + + ctrl = readb(idev->base + CORE_I2C_CTRL); + ctrl |= CTRL_STA; + writeb(ctrl, idev->base + CORE_I2C_CTRL); + + time_left = wait_for_completion_timeout(&idev->msg_complete, + idev->adapter.timeout); + if (!time_left) + return -ETIMEDOUT; + + return idev->msg_err; +} + +static int mchp_corei2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct mchp_corei2c_dev *idev = i2c_get_adapdata(adap); + int i, ret; + + for (i = 0; i < num; i++) { + ret = mchp_corei2c_xfer_msg(idev, msgs++); + if (ret) + return ret; + } + + return num; +} + +static u32 mchp_corei2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm mchp_corei2c_algo = { + .master_xfer = mchp_corei2c_xfer, + .functionality = mchp_corei2c_func, +}; + +static int mchp_corei2c_probe(struct platform_device *pdev) +{ + struct mchp_corei2c_dev *idev; + struct resource *res; + int irq, ret; + + idev = devm_kzalloc(&pdev->dev, sizeof(*idev), GFP_KERNEL); + if (!idev) + return -ENOMEM; + + idev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(idev->base)) + return PTR_ERR(idev->base); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + idev->i2c_clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(idev->i2c_clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(idev->i2c_clk), + "missing clock\n"); + + idev->dev = &pdev->dev; + init_completion(&idev->msg_complete); + + ret = device_property_read_u32(idev->dev, "clock-frequency", + &idev->bus_clk_rate); + if (ret || !idev->bus_clk_rate) { + dev_info(&pdev->dev, "default to 100kHz\n"); + idev->bus_clk_rate = 100000; + } + + if (idev->bus_clk_rate > 400000) + return dev_err_probe(&pdev->dev, -EINVAL, + "clock-frequency too high: %d\n", + idev->bus_clk_rate); + + /* + * This driver supports both the hard peripherals & soft FPGA cores. + * The hard peripherals do not have shared IRQs, but we don't have + * control over what way the interrupts are wired for the soft cores. + */ + ret = devm_request_irq(&pdev->dev, irq, mchp_corei2c_isr, IRQF_SHARED, + pdev->name, idev); + if (ret) + return dev_err_probe(&pdev->dev, ret, + "failed to claim irq %d\n", irq); + + ret = clk_prepare_enable(idev->i2c_clk); + if (ret) + return dev_err_probe(&pdev->dev, ret, + "failed to enable clock\n"); + + ret = mchp_corei2c_init(idev); + if (ret) { + clk_disable_unprepare(idev->i2c_clk); + return dev_err_probe(&pdev->dev, ret, "failed to program clock divider\n"); + } + + i2c_set_adapdata(&idev->adapter, idev); + snprintf(idev->adapter.name, sizeof(idev->adapter.name), + "Microchip I2C hw bus at %08lx", (unsigned long)res->start); + idev->adapter.owner = THIS_MODULE; + idev->adapter.algo = &mchp_corei2c_algo; + idev->adapter.dev.parent = &pdev->dev; + idev->adapter.dev.of_node = pdev->dev.of_node; + idev->adapter.timeout = HZ; + + platform_set_drvdata(pdev, idev); + + ret = i2c_add_adapter(&idev->adapter); + if (ret) { + clk_disable_unprepare(idev->i2c_clk); + return ret; + } + + dev_info(&pdev->dev, "registered CoreI2C bus driver\n"); + + return 0; +} + +static void mchp_corei2c_remove(struct platform_device *pdev) +{ + struct mchp_corei2c_dev *idev = platform_get_drvdata(pdev); + + clk_disable_unprepare(idev->i2c_clk); + i2c_del_adapter(&idev->adapter); +} + +static const struct of_device_id mchp_corei2c_of_match[] = { + { .compatible = "microchip,mpfs-i2c" }, + { .compatible = "microchip,corei2c-rtl-v7" }, + {}, +}; +MODULE_DEVICE_TABLE(of, mchp_corei2c_of_match); + +static struct platform_driver mchp_corei2c_driver = { + .probe = mchp_corei2c_probe, + .remove_new = mchp_corei2c_remove, + .driver = { + .name = "microchip-corei2c", + .of_match_table = mchp_corei2c_of_match, + }, +}; + +module_platform_driver(mchp_corei2c_driver); + +MODULE_DESCRIPTION("Microchip CoreI2C bus driver"); +MODULE_AUTHOR("Daire McNamara <daire.mcnamara@microchip.com>"); +MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-mlxbf.c b/drivers/i2c/busses/i2c-mlxbf.c new file mode 100644 index 000000000..b3a73921a --- /dev/null +++ b/drivers/i2c/busses/i2c-mlxbf.c @@ -0,0 +1,2493 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Mellanox BlueField I2C bus driver + * + * Copyright (C) 2020 Mellanox Technologies, Ltd. + */ + +#include <linux/acpi.h> +#include <linux/bitfield.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/i2c.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/string.h> + +/* Defines what functionality is present. */ +#define MLXBF_I2C_FUNC_SMBUS_BLOCK \ + (I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL) + +#define MLXBF_I2C_FUNC_SMBUS_DEFAULT \ + (I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA | \ + I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_I2C_BLOCK | \ + I2C_FUNC_SMBUS_PROC_CALL) + +#define MLXBF_I2C_FUNC_ALL \ + (MLXBF_I2C_FUNC_SMBUS_DEFAULT | MLXBF_I2C_FUNC_SMBUS_BLOCK | \ + I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SLAVE) + +/* Shared resources info in BlueField platforms. */ + +#define MLXBF_I2C_COALESCE_TYU_ADDR 0x02801300 +#define MLXBF_I2C_COALESCE_TYU_SIZE 0x010 + +#define MLXBF_I2C_GPIO_TYU_ADDR 0x02802000 +#define MLXBF_I2C_GPIO_TYU_SIZE 0x100 + +#define MLXBF_I2C_COREPLL_TYU_ADDR 0x02800358 +#define MLXBF_I2C_COREPLL_TYU_SIZE 0x008 + +#define MLXBF_I2C_COREPLL_YU_ADDR 0x02800c30 +#define MLXBF_I2C_COREPLL_YU_SIZE 0x00c + +#define MLXBF_I2C_COREPLL_RSH_YU_ADDR 0x13409824 +#define MLXBF_I2C_COREPLL_RSH_YU_SIZE 0x00c + +#define MLXBF_I2C_SHARED_RES_MAX 3 + +/* + * Note that the following SMBus, CAUSE, GPIO and PLL register addresses + * refer to their respective offsets relative to the corresponding + * memory-mapped region whose addresses are specified in either the DT or + * the ACPI tables or above. + */ + +/* + * SMBus Master core clock frequency. Timing configurations are + * strongly dependent on the core clock frequency of the SMBus + * Master. Default value is set to 400MHz. + */ +#define MLXBF_I2C_TYU_PLL_OUT_FREQ (400 * 1000 * 1000) +/* Reference clock for Bluefield - 156 MHz. */ +#define MLXBF_I2C_PLL_IN_FREQ 156250000ULL + +/* Constant used to determine the PLL frequency. */ +#define MLNXBF_I2C_COREPLL_CONST 16384ULL + +#define MLXBF_I2C_FREQUENCY_1GHZ 1000000000ULL + +/* PLL registers. */ +#define MLXBF_I2C_CORE_PLL_REG1 0x4 +#define MLXBF_I2C_CORE_PLL_REG2 0x8 + +/* OR cause register. */ +#define MLXBF_I2C_CAUSE_OR_EVTEN0 0x14 +#define MLXBF_I2C_CAUSE_OR_CLEAR 0x18 + +/* Arbiter Cause Register. */ +#define MLXBF_I2C_CAUSE_ARBITER 0x1c + +/* + * Cause Status flags. Note that those bits might be considered + * as interrupt enabled bits. + */ + +/* Transaction ended with STOP. */ +#define MLXBF_I2C_CAUSE_TRANSACTION_ENDED BIT(0) +/* Master arbitration lost. */ +#define MLXBF_I2C_CAUSE_M_ARBITRATION_LOST BIT(1) +/* Unexpected start detected. */ +#define MLXBF_I2C_CAUSE_UNEXPECTED_START BIT(2) +/* Unexpected stop detected. */ +#define MLXBF_I2C_CAUSE_UNEXPECTED_STOP BIT(3) +/* Wait for transfer continuation. */ +#define MLXBF_I2C_CAUSE_WAIT_FOR_FW_DATA BIT(4) +/* Failed to generate STOP. */ +#define MLXBF_I2C_CAUSE_PUT_STOP_FAILED BIT(5) +/* Failed to generate START. */ +#define MLXBF_I2C_CAUSE_PUT_START_FAILED BIT(6) +/* Clock toggle completed. */ +#define MLXBF_I2C_CAUSE_CLK_TOGGLE_DONE BIT(7) +/* Transfer timeout occurred. */ +#define MLXBF_I2C_CAUSE_M_FW_TIMEOUT BIT(8) +/* Master busy bit reset. */ +#define MLXBF_I2C_CAUSE_M_GW_BUSY_FALL BIT(9) + +#define MLXBF_I2C_CAUSE_MASTER_ARBITER_BITS_MASK GENMASK(9, 0) + +#define MLXBF_I2C_CAUSE_MASTER_STATUS_ERROR \ + (MLXBF_I2C_CAUSE_M_ARBITRATION_LOST | \ + MLXBF_I2C_CAUSE_UNEXPECTED_START | \ + MLXBF_I2C_CAUSE_UNEXPECTED_STOP | \ + MLXBF_I2C_CAUSE_PUT_STOP_FAILED | \ + MLXBF_I2C_CAUSE_PUT_START_FAILED | \ + MLXBF_I2C_CAUSE_CLK_TOGGLE_DONE | \ + MLXBF_I2C_CAUSE_M_FW_TIMEOUT) + +/* + * Slave cause status flags. Note that those bits might be considered + * as interrupt enabled bits. + */ + +/* Write transaction received successfully. */ +#define MLXBF_I2C_CAUSE_WRITE_SUCCESS BIT(0) +/* Read transaction received, waiting for response. */ +#define MLXBF_I2C_CAUSE_READ_WAIT_FW_RESPONSE BIT(13) +/* Slave busy bit reset. */ +#define MLXBF_I2C_CAUSE_S_GW_BUSY_FALL BIT(18) + +/* Cause coalesce registers. */ +#define MLXBF_I2C_CAUSE_COALESCE_0 0x00 + +#define MLXBF_I2C_CAUSE_TYU_SLAVE_BIT 3 +#define MLXBF_I2C_CAUSE_YU_SLAVE_BIT 1 + +/* Functional enable register. */ +#define MLXBF_I2C_GPIO_0_FUNC_EN_0 0x28 +/* Force OE enable register. */ +#define MLXBF_I2C_GPIO_0_FORCE_OE_EN 0x30 +/* + * Note that Smbus GWs are on GPIOs 30:25. Two pins are used to control + * SDA/SCL lines: + * + * SMBUS GW0 -> bits[26:25] + * SMBUS GW1 -> bits[28:27] + * SMBUS GW2 -> bits[30:29] + */ +#define MLXBF_I2C_GPIO_SMBUS_GW_PINS(num) (25 + ((num) << 1)) + +/* Note that gw_id can be 0,1 or 2. */ +#define MLXBF_I2C_GPIO_SMBUS_GW_MASK(num) \ + (0xffffffff & (~(0x3 << MLXBF_I2C_GPIO_SMBUS_GW_PINS(num)))) + +#define MLXBF_I2C_GPIO_SMBUS_GW_RESET_PINS(num, val) \ + ((val) & MLXBF_I2C_GPIO_SMBUS_GW_MASK(num)) + +#define MLXBF_I2C_GPIO_SMBUS_GW_ASSERT_PINS(num, val) \ + ((val) | (0x3 << MLXBF_I2C_GPIO_SMBUS_GW_PINS(num))) + +/* + * Defines SMBus operating frequency and core clock frequency. + * According to ADB files, default values are compliant to 100KHz SMBus + * @ 400MHz core clock. The driver should be able to calculate core + * frequency based on PLL parameters. + */ +#define MLXBF_I2C_COREPLL_FREQ MLXBF_I2C_TYU_PLL_OUT_FREQ + +/* Core PLL TYU configuration. */ +#define MLXBF_I2C_COREPLL_CORE_F_TYU_MASK GENMASK(15, 3) +#define MLXBF_I2C_COREPLL_CORE_OD_TYU_MASK GENMASK(19, 16) +#define MLXBF_I2C_COREPLL_CORE_R_TYU_MASK GENMASK(25, 20) + +/* Core PLL YU configuration. */ +#define MLXBF_I2C_COREPLL_CORE_F_YU_MASK GENMASK(25, 0) +#define MLXBF_I2C_COREPLL_CORE_OD_YU_MASK GENMASK(3, 0) +#define MLXBF_I2C_COREPLL_CORE_R_YU_MASK GENMASK(31, 26) + +/* SMBus timing parameters. */ +#define MLXBF_I2C_SMBUS_TIMER_SCL_LOW_SCL_HIGH 0x00 +#define MLXBF_I2C_SMBUS_TIMER_FALL_RISE_SPIKE 0x04 +#define MLXBF_I2C_SMBUS_TIMER_THOLD 0x08 +#define MLXBF_I2C_SMBUS_TIMER_TSETUP_START_STOP 0x0c +#define MLXBF_I2C_SMBUS_TIMER_TSETUP_DATA 0x10 +#define MLXBF_I2C_SMBUS_THIGH_MAX_TBUF 0x14 +#define MLXBF_I2C_SMBUS_SCL_LOW_TIMEOUT 0x18 + +#define MLXBF_I2C_SHIFT_0 0 +#define MLXBF_I2C_SHIFT_8 8 +#define MLXBF_I2C_SHIFT_16 16 +#define MLXBF_I2C_SHIFT_24 24 + +#define MLXBF_I2C_MASK_8 GENMASK(7, 0) +#define MLXBF_I2C_MASK_16 GENMASK(15, 0) + +#define MLXBF_I2C_MST_ADDR_OFFSET 0x200 + +/* SMBus Master GW. */ +#define MLXBF_I2C_SMBUS_MASTER_GW 0x0 +/* Number of bytes received and sent. */ +#define MLXBF_I2C_YU_SMBUS_RS_BYTES 0x100 +#define MLXBF_I2C_RSH_YU_SMBUS_RS_BYTES 0x10c +/* Packet error check (PEC) value. */ +#define MLXBF_I2C_SMBUS_MASTER_PEC 0x104 +/* Status bits (ACK/NACK/FW Timeout). */ +#define MLXBF_I2C_SMBUS_MASTER_STATUS 0x108 +/* SMbus Master Finite State Machine. */ +#define MLXBF_I2C_YU_SMBUS_MASTER_FSM 0x110 +#define MLXBF_I2C_RSH_YU_SMBUS_MASTER_FSM 0x100 + +/* SMBus master GW control bits offset in MLXBF_I2C_SMBUS_MASTER_GW[31:3]. */ +#define MLXBF_I2C_MASTER_LOCK_BIT BIT(31) /* Lock bit. */ +#define MLXBF_I2C_MASTER_BUSY_BIT BIT(30) /* Busy bit. */ +#define MLXBF_I2C_MASTER_START_BIT BIT(29) /* Control start. */ +#define MLXBF_I2C_MASTER_CTL_WRITE_BIT BIT(28) /* Control write phase. */ +#define MLXBF_I2C_MASTER_CTL_READ_BIT BIT(19) /* Control read phase. */ +#define MLXBF_I2C_MASTER_STOP_BIT BIT(3) /* Control stop. */ + +#define MLXBF_I2C_MASTER_ENABLE \ + (MLXBF_I2C_MASTER_LOCK_BIT | MLXBF_I2C_MASTER_BUSY_BIT | \ + MLXBF_I2C_MASTER_START_BIT | MLXBF_I2C_MASTER_STOP_BIT) + +#define MLXBF_I2C_MASTER_ENABLE_WRITE \ + (MLXBF_I2C_MASTER_ENABLE | MLXBF_I2C_MASTER_CTL_WRITE_BIT) + +#define MLXBF_I2C_MASTER_ENABLE_READ \ + (MLXBF_I2C_MASTER_ENABLE | MLXBF_I2C_MASTER_CTL_READ_BIT) + +#define MLXBF_I2C_MASTER_WRITE_SHIFT 21 /* Control write bytes */ +#define MLXBF_I2C_MASTER_SEND_PEC_SHIFT 20 /* Send PEC byte when set to 1 */ +#define MLXBF_I2C_MASTER_PARSE_EXP_SHIFT 11 /* Control parse expected bytes */ +#define MLXBF_I2C_MASTER_SLV_ADDR_SHIFT 12 /* Slave address */ +#define MLXBF_I2C_MASTER_READ_SHIFT 4 /* Control read bytes */ + +/* SMBus master GW Data descriptor. */ +#define MLXBF_I2C_MASTER_DATA_DESC_ADDR 0x80 +#define MLXBF_I2C_MASTER_DATA_DESC_SIZE 0x80 /* Size in bytes. */ + +/* Maximum bytes to read/write per SMBus transaction. */ +#define MLXBF_I2C_MASTER_DATA_R_LENGTH MLXBF_I2C_MASTER_DATA_DESC_SIZE +#define MLXBF_I2C_MASTER_DATA_W_LENGTH (MLXBF_I2C_MASTER_DATA_DESC_SIZE - 1) + +/* All bytes were transmitted. */ +#define MLXBF_I2C_SMBUS_STATUS_BYTE_CNT_DONE BIT(0) +/* NACK received. */ +#define MLXBF_I2C_SMBUS_STATUS_NACK_RCV BIT(1) +/* Slave's byte count >128 bytes. */ +#define MLXBF_I2C_SMBUS_STATUS_READ_ERR BIT(2) +/* Timeout occurred. */ +#define MLXBF_I2C_SMBUS_STATUS_FW_TIMEOUT BIT(3) + +#define MLXBF_I2C_SMBUS_MASTER_STATUS_MASK GENMASK(3, 0) + +#define MLXBF_I2C_SMBUS_MASTER_STATUS_ERROR \ + (MLXBF_I2C_SMBUS_STATUS_NACK_RCV | \ + MLXBF_I2C_SMBUS_STATUS_READ_ERR | \ + MLXBF_I2C_SMBUS_STATUS_FW_TIMEOUT) + +#define MLXBF_I2C_SMBUS_MASTER_FSM_STOP_MASK BIT(31) +#define MLXBF_I2C_SMBUS_MASTER_FSM_PS_STATE_MASK BIT(15) + +#define MLXBF_I2C_SLV_ADDR_OFFSET 0x400 + +/* SMBus slave GW. */ +#define MLXBF_I2C_SMBUS_SLAVE_GW 0x0 +/* Number of bytes received and sent from/to master. */ +#define MLXBF_I2C_SMBUS_SLAVE_RS_MASTER_BYTES 0x100 +/* Packet error check (PEC) value. */ +#define MLXBF_I2C_SMBUS_SLAVE_PEC 0x104 +/* SMBus slave Finite State Machine (FSM). */ +#define MLXBF_I2C_SMBUS_SLAVE_FSM 0x110 +/* + * Should be set when all raised causes handled, and cleared by HW on + * every new cause. + */ +#define MLXBF_I2C_SMBUS_SLAVE_READY 0x12c + +/* SMBus slave GW control bits offset in MLXBF_I2C_SMBUS_SLAVE_GW[31:19]. */ +#define MLXBF_I2C_SLAVE_BUSY_BIT BIT(30) /* Busy bit. */ +#define MLXBF_I2C_SLAVE_WRITE_BIT BIT(29) /* Control write enable. */ + +#define MLXBF_I2C_SLAVE_ENABLE \ + (MLXBF_I2C_SLAVE_BUSY_BIT | MLXBF_I2C_SLAVE_WRITE_BIT) + +#define MLXBF_I2C_SLAVE_WRITE_BYTES_SHIFT 22 /* Number of bytes to write. */ +#define MLXBF_I2C_SLAVE_SEND_PEC_SHIFT 21 /* Send PEC byte shift. */ + +/* SMBus slave GW Data descriptor. */ +#define MLXBF_I2C_SLAVE_DATA_DESC_ADDR 0x80 +#define MLXBF_I2C_SLAVE_DATA_DESC_SIZE 0x80 /* Size in bytes. */ + +/* SMbus slave configuration registers. */ +#define MLXBF_I2C_SMBUS_SLAVE_ADDR_CFG 0x114 +#define MLXBF_I2C_SMBUS_SLAVE_ADDR_CNT 16 +#define MLXBF_I2C_SMBUS_SLAVE_ADDR_EN_BIT BIT(7) +#define MLXBF_I2C_SMBUS_SLAVE_ADDR_MASK GENMASK(6, 0) + +/* + * Timeout is given in microsends. Note also that timeout handling is not + * exact. + */ +#define MLXBF_I2C_SMBUS_TIMEOUT (300 * 1000) /* 300ms */ +#define MLXBF_I2C_SMBUS_LOCK_POLL_TIMEOUT (300 * 1000) /* 300ms */ + +/* Polling frequency in microseconds. */ +#define MLXBF_I2C_POLL_FREQ_IN_USEC 200 + +#define MLXBF_I2C_SMBUS_OP_CNT_1 1 +#define MLXBF_I2C_SMBUS_OP_CNT_2 2 +#define MLXBF_I2C_SMBUS_OP_CNT_3 3 +#define MLXBF_I2C_SMBUS_MAX_OP_CNT MLXBF_I2C_SMBUS_OP_CNT_3 + +/* Helper macro to define an I2C resource parameters. */ +#define MLXBF_I2C_RES_PARAMS(addr, size, str) \ + { \ + .start = (addr), \ + .end = (addr) + (size) - 1, \ + .name = (str) \ + } + +enum { + MLXBF_I2C_TIMING_100KHZ = 100000, + MLXBF_I2C_TIMING_400KHZ = 400000, + MLXBF_I2C_TIMING_1000KHZ = 1000000, +}; + +enum { + MLXBF_I2C_F_READ = BIT(0), + MLXBF_I2C_F_WRITE = BIT(1), + MLXBF_I2C_F_NORESTART = BIT(3), + MLXBF_I2C_F_SMBUS_OPERATION = BIT(4), + MLXBF_I2C_F_SMBUS_BLOCK = BIT(5), + MLXBF_I2C_F_SMBUS_PEC = BIT(6), + MLXBF_I2C_F_SMBUS_PROCESS_CALL = BIT(7), +}; + +/* Mellanox BlueField chip type. */ +enum mlxbf_i2c_chip_type { + MLXBF_I2C_CHIP_TYPE_1, /* Mellanox BlueField-1 chip. */ + MLXBF_I2C_CHIP_TYPE_2, /* Mellanox BlueField-2 chip. */ + MLXBF_I2C_CHIP_TYPE_3 /* Mellanox BlueField-3 chip. */ +}; + +/* List of chip resources that are being accessed by the driver. */ +enum { + MLXBF_I2C_SMBUS_RES, + MLXBF_I2C_MST_CAUSE_RES, + MLXBF_I2C_SLV_CAUSE_RES, + MLXBF_I2C_COALESCE_RES, + MLXBF_I2C_SMBUS_TIMER_RES, + MLXBF_I2C_SMBUS_MST_RES, + MLXBF_I2C_SMBUS_SLV_RES, + MLXBF_I2C_COREPLL_RES, + MLXBF_I2C_GPIO_RES, + MLXBF_I2C_END_RES +}; + +/* Encapsulates timing parameters. */ +struct mlxbf_i2c_timings { + u16 scl_high; /* Clock high period. */ + u16 scl_low; /* Clock low period. */ + u8 sda_rise; /* Data rise time. */ + u8 sda_fall; /* Data fall time. */ + u8 scl_rise; /* Clock rise time. */ + u8 scl_fall; /* Clock fall time. */ + u16 hold_start; /* Hold time after (REPEATED) START. */ + u16 hold_data; /* Data hold time. */ + u16 setup_start; /* REPEATED START condition setup time. */ + u16 setup_stop; /* STOP condition setup time. */ + u16 setup_data; /* Data setup time. */ + u16 pad; /* Padding. */ + u16 buf; /* Bus free time between STOP and START. */ + u16 thigh_max; /* Thigh max. */ + u32 timeout; /* Detect clock low timeout. */ +}; + +struct mlxbf_i2c_smbus_operation { + u32 flags; + u32 length; /* Buffer length in bytes. */ + u8 *buffer; +}; + +struct mlxbf_i2c_smbus_request { + u8 slave; + u8 operation_cnt; + struct mlxbf_i2c_smbus_operation operation[MLXBF_I2C_SMBUS_MAX_OP_CNT]; +}; + +struct mlxbf_i2c_resource { + void __iomem *io; + struct resource *params; + struct mutex *lock; /* Mutex to protect mlxbf_i2c_resource. */ + u8 type; +}; + +struct mlxbf_i2c_chip_info { + enum mlxbf_i2c_chip_type type; + /* Chip shared resources that are being used by the I2C controller. */ + struct mlxbf_i2c_resource *shared_res[MLXBF_I2C_SHARED_RES_MAX]; + + /* Callback to calculate the core PLL frequency. */ + u64 (*calculate_freq)(struct mlxbf_i2c_resource *corepll_res); + + /* Registers' address offset */ + u32 smbus_master_rs_bytes_off; + u32 smbus_master_fsm_off; +}; + +struct mlxbf_i2c_priv { + const struct mlxbf_i2c_chip_info *chip; + struct i2c_adapter adap; + struct mlxbf_i2c_resource *smbus; + struct mlxbf_i2c_resource *timer; + struct mlxbf_i2c_resource *mst; + struct mlxbf_i2c_resource *slv; + struct mlxbf_i2c_resource *mst_cause; + struct mlxbf_i2c_resource *slv_cause; + struct mlxbf_i2c_resource *coalesce; + u64 frequency; /* Core frequency in Hz. */ + int bus; /* Physical bus identifier. */ + int irq; + struct i2c_client *slave[MLXBF_I2C_SMBUS_SLAVE_ADDR_CNT]; + u32 resource_version; +}; + +/* Core PLL frequency. */ +static u64 mlxbf_i2c_corepll_frequency; + +static struct resource mlxbf_i2c_coalesce_tyu_params = + MLXBF_I2C_RES_PARAMS(MLXBF_I2C_COALESCE_TYU_ADDR, + MLXBF_I2C_COALESCE_TYU_SIZE, + "COALESCE_MEM"); +static struct resource mlxbf_i2c_corepll_tyu_params = + MLXBF_I2C_RES_PARAMS(MLXBF_I2C_COREPLL_TYU_ADDR, + MLXBF_I2C_COREPLL_TYU_SIZE, + "COREPLL_MEM"); +static struct resource mlxbf_i2c_corepll_yu_params = + MLXBF_I2C_RES_PARAMS(MLXBF_I2C_COREPLL_YU_ADDR, + MLXBF_I2C_COREPLL_YU_SIZE, + "COREPLL_MEM"); +static struct resource mlxbf_i2c_corepll_rsh_yu_params = + MLXBF_I2C_RES_PARAMS(MLXBF_I2C_COREPLL_RSH_YU_ADDR, + MLXBF_I2C_COREPLL_RSH_YU_SIZE, + "COREPLL_MEM"); +static struct resource mlxbf_i2c_gpio_tyu_params = + MLXBF_I2C_RES_PARAMS(MLXBF_I2C_GPIO_TYU_ADDR, + MLXBF_I2C_GPIO_TYU_SIZE, + "GPIO_MEM"); + +static struct mutex mlxbf_i2c_coalesce_lock; +static struct mutex mlxbf_i2c_corepll_lock; +static struct mutex mlxbf_i2c_gpio_lock; + +static struct mlxbf_i2c_resource mlxbf_i2c_coalesce_res[] = { + [MLXBF_I2C_CHIP_TYPE_1] = { + .params = &mlxbf_i2c_coalesce_tyu_params, + .lock = &mlxbf_i2c_coalesce_lock, + .type = MLXBF_I2C_COALESCE_RES + }, + {} +}; + +static struct mlxbf_i2c_resource mlxbf_i2c_corepll_res[] = { + [MLXBF_I2C_CHIP_TYPE_1] = { + .params = &mlxbf_i2c_corepll_tyu_params, + .lock = &mlxbf_i2c_corepll_lock, + .type = MLXBF_I2C_COREPLL_RES + }, + [MLXBF_I2C_CHIP_TYPE_2] = { + .params = &mlxbf_i2c_corepll_yu_params, + .lock = &mlxbf_i2c_corepll_lock, + .type = MLXBF_I2C_COREPLL_RES, + }, + [MLXBF_I2C_CHIP_TYPE_3] = { + .params = &mlxbf_i2c_corepll_rsh_yu_params, + .lock = &mlxbf_i2c_corepll_lock, + .type = MLXBF_I2C_COREPLL_RES, + } +}; + +static struct mlxbf_i2c_resource mlxbf_i2c_gpio_res[] = { + [MLXBF_I2C_CHIP_TYPE_1] = { + .params = &mlxbf_i2c_gpio_tyu_params, + .lock = &mlxbf_i2c_gpio_lock, + .type = MLXBF_I2C_GPIO_RES + }, + {} +}; + +static u8 mlxbf_i2c_bus_count; + +static struct mutex mlxbf_i2c_bus_lock; + +/* + * Function to poll a set of bits at a specific address; it checks whether + * the bits are equal to zero when eq_zero is set to 'true', and not equal + * to zero when eq_zero is set to 'false'. + * Note that the timeout is given in microseconds. + */ +static u32 mlxbf_i2c_poll(void __iomem *io, u32 addr, u32 mask, + bool eq_zero, u32 timeout) +{ + u32 bits; + + timeout = (timeout / MLXBF_I2C_POLL_FREQ_IN_USEC) + 1; + + do { + bits = readl(io + addr) & mask; + if (eq_zero ? bits == 0 : bits != 0) + return eq_zero ? 1 : bits; + udelay(MLXBF_I2C_POLL_FREQ_IN_USEC); + } while (timeout-- != 0); + + return 0; +} + +/* + * SW must make sure that the SMBus Master GW is idle before starting + * a transaction. Accordingly, this function polls the Master FSM stop + * bit; it returns false when the bit is asserted, true if not. + */ +static bool mlxbf_i2c_smbus_master_wait_for_idle(struct mlxbf_i2c_priv *priv) +{ + u32 mask = MLXBF_I2C_SMBUS_MASTER_FSM_STOP_MASK; + u32 addr = priv->chip->smbus_master_fsm_off; + u32 timeout = MLXBF_I2C_SMBUS_TIMEOUT; + + if (mlxbf_i2c_poll(priv->mst->io, addr, mask, true, timeout)) + return true; + + return false; +} + +/* + * wait for the lock to be released before acquiring it. + */ +static bool mlxbf_i2c_smbus_master_lock(struct mlxbf_i2c_priv *priv) +{ + if (mlxbf_i2c_poll(priv->mst->io, MLXBF_I2C_SMBUS_MASTER_GW, + MLXBF_I2C_MASTER_LOCK_BIT, true, + MLXBF_I2C_SMBUS_LOCK_POLL_TIMEOUT)) + return true; + + return false; +} + +static void mlxbf_i2c_smbus_master_unlock(struct mlxbf_i2c_priv *priv) +{ + /* Clear the gw to clear the lock */ + writel(0, priv->mst->io + MLXBF_I2C_SMBUS_MASTER_GW); +} + +static bool mlxbf_i2c_smbus_transaction_success(u32 master_status, + u32 cause_status) +{ + /* + * When transaction ended with STOP, all bytes were transmitted, + * and no NACK received, then the transaction ended successfully. + * On the other hand, when the GW is configured with the stop bit + * de-asserted then the SMBus expects the following GW configuration + * for transfer continuation. + */ + if ((cause_status & MLXBF_I2C_CAUSE_WAIT_FOR_FW_DATA) || + ((cause_status & MLXBF_I2C_CAUSE_TRANSACTION_ENDED) && + (master_status & MLXBF_I2C_SMBUS_STATUS_BYTE_CNT_DONE) && + !(master_status & MLXBF_I2C_SMBUS_STATUS_NACK_RCV))) + return true; + + return false; +} + +/* + * Poll SMBus master status and return transaction status, + * i.e. whether succeeded or failed. I2C and SMBus fault codes + * are returned as negative numbers from most calls, with zero + * or some positive number indicating a non-fault return. + */ +static int mlxbf_i2c_smbus_check_status(struct mlxbf_i2c_priv *priv) +{ + u32 master_status_bits; + u32 cause_status_bits; + + /* + * GW busy bit is raised by the driver and cleared by the HW + * when the transaction is completed. The busy bit is a good + * indicator of transaction status. So poll the busy bit, and + * then read the cause and master status bits to determine if + * errors occurred during the transaction. + */ + mlxbf_i2c_poll(priv->mst->io, MLXBF_I2C_SMBUS_MASTER_GW, + MLXBF_I2C_MASTER_BUSY_BIT, true, + MLXBF_I2C_SMBUS_TIMEOUT); + + /* Read cause status bits. */ + cause_status_bits = readl(priv->mst_cause->io + + MLXBF_I2C_CAUSE_ARBITER); + cause_status_bits &= MLXBF_I2C_CAUSE_MASTER_ARBITER_BITS_MASK; + + /* + * Parse both Cause and Master GW bits, then return transaction status. + */ + + master_status_bits = readl(priv->mst->io + + MLXBF_I2C_SMBUS_MASTER_STATUS); + master_status_bits &= MLXBF_I2C_SMBUS_MASTER_STATUS_MASK; + + if (mlxbf_i2c_smbus_transaction_success(master_status_bits, + cause_status_bits)) + return 0; + + /* + * In case of timeout on GW busy, the ISR will clear busy bit but + * transaction ended bits cause will not be set so the transaction + * fails. Then, we must check Master GW status bits. + */ + if ((master_status_bits & MLXBF_I2C_SMBUS_MASTER_STATUS_ERROR) && + (cause_status_bits & (MLXBF_I2C_CAUSE_TRANSACTION_ENDED | + MLXBF_I2C_CAUSE_M_GW_BUSY_FALL))) + return -EIO; + + if (cause_status_bits & MLXBF_I2C_CAUSE_MASTER_STATUS_ERROR) + return -EAGAIN; + + return -ETIMEDOUT; +} + +static void mlxbf_i2c_smbus_write_data(struct mlxbf_i2c_priv *priv, + const u8 *data, u8 length, u32 addr, + bool is_master) +{ + u8 offset, aligned_length; + u32 data32; + + aligned_length = round_up(length, 4); + + /* + * Copy data bytes from 4-byte aligned source buffer. + * Data copied to the Master GW Data Descriptor MUST be shifted + * left so the data starts at the MSB of the descriptor registers + * as required by the underlying hardware. Enable byte swapping + * when writing data bytes to the 32 * 32-bit HW Data registers + * a.k.a Master GW Data Descriptor. + */ + for (offset = 0; offset < aligned_length; offset += sizeof(u32)) { + data32 = *((u32 *)(data + offset)); + if (is_master) + iowrite32be(data32, priv->mst->io + addr + offset); + else + iowrite32be(data32, priv->slv->io + addr + offset); + } +} + +static void mlxbf_i2c_smbus_read_data(struct mlxbf_i2c_priv *priv, + u8 *data, u8 length, u32 addr, + bool is_master) +{ + u32 data32, mask; + u8 byte, offset; + + mask = sizeof(u32) - 1; + + /* + * Data bytes in the Master GW Data Descriptor are shifted left + * so the data starts at the MSB of the descriptor registers as + * set by the underlying hardware. Enable byte swapping while + * reading data bytes from the 32 * 32-bit HW Data registers + * a.k.a Master GW Data Descriptor. + */ + + for (offset = 0; offset < (length & ~mask); offset += sizeof(u32)) { + if (is_master) + data32 = ioread32be(priv->mst->io + addr + offset); + else + data32 = ioread32be(priv->slv->io + addr + offset); + *((u32 *)(data + offset)) = data32; + } + + if (!(length & mask)) + return; + + if (is_master) + data32 = ioread32be(priv->mst->io + addr + offset); + else + data32 = ioread32be(priv->slv->io + addr + offset); + + for (byte = 0; byte < (length & mask); byte++) { + data[offset + byte] = data32 & GENMASK(7, 0); + data32 = ror32(data32, MLXBF_I2C_SHIFT_8); + } +} + +static int mlxbf_i2c_smbus_enable(struct mlxbf_i2c_priv *priv, u8 slave, + u8 len, u8 block_en, u8 pec_en, bool read) +{ + u32 command; + + /* Set Master GW control word. */ + if (read) { + command = MLXBF_I2C_MASTER_ENABLE_READ; + command |= rol32(len, MLXBF_I2C_MASTER_READ_SHIFT); + } else { + command = MLXBF_I2C_MASTER_ENABLE_WRITE; + command |= rol32(len, MLXBF_I2C_MASTER_WRITE_SHIFT); + } + command |= rol32(slave, MLXBF_I2C_MASTER_SLV_ADDR_SHIFT); + command |= rol32(block_en, MLXBF_I2C_MASTER_PARSE_EXP_SHIFT); + command |= rol32(pec_en, MLXBF_I2C_MASTER_SEND_PEC_SHIFT); + + /* Clear status bits. */ + writel(0x0, priv->mst->io + MLXBF_I2C_SMBUS_MASTER_STATUS); + /* Set the cause data. */ + writel(~0x0, priv->mst_cause->io + MLXBF_I2C_CAUSE_OR_CLEAR); + /* Zero PEC byte. */ + writel(0x0, priv->mst->io + MLXBF_I2C_SMBUS_MASTER_PEC); + /* Zero byte count. */ + writel(0x0, priv->mst->io + priv->chip->smbus_master_rs_bytes_off); + + /* GW activation. */ + writel(command, priv->mst->io + MLXBF_I2C_SMBUS_MASTER_GW); + + /* + * Poll master status and check status bits. An ACK is sent when + * completing writing data to the bus (Master 'byte_count_done' bit + * is set to 1). + */ + return mlxbf_i2c_smbus_check_status(priv); +} + +static int +mlxbf_i2c_smbus_start_transaction(struct mlxbf_i2c_priv *priv, + struct mlxbf_i2c_smbus_request *request) +{ + u8 data_desc[MLXBF_I2C_MASTER_DATA_DESC_SIZE] = { 0 }; + u8 op_idx, data_idx, data_len, write_len, read_len; + struct mlxbf_i2c_smbus_operation *operation; + u8 read_en, write_en, block_en, pec_en; + u8 slave, flags, addr; + u8 *read_buf; + int ret = 0; + + if (request->operation_cnt > MLXBF_I2C_SMBUS_MAX_OP_CNT) + return -EINVAL; + + read_buf = NULL; + data_idx = 0; + read_en = 0; + write_en = 0; + write_len = 0; + read_len = 0; + block_en = 0; + pec_en = 0; + slave = request->slave & GENMASK(6, 0); + addr = slave << 1; + + /* + * Try to acquire the smbus gw lock before any reads of the GW register since + * a read sets the lock. + */ + if (WARN_ON(!mlxbf_i2c_smbus_master_lock(priv))) + return -EBUSY; + + /* Check whether the HW is idle */ + if (WARN_ON(!mlxbf_i2c_smbus_master_wait_for_idle(priv))) { + ret = -EBUSY; + goto out_unlock; + } + + /* Set first byte. */ + data_desc[data_idx++] = addr; + + for (op_idx = 0; op_idx < request->operation_cnt; op_idx++) { + operation = &request->operation[op_idx]; + flags = operation->flags; + + /* + * Note that read and write operations might be handled by a + * single command. If the MLXBF_I2C_F_SMBUS_OPERATION is set + * then write command byte and set the optional SMBus specific + * bits such as block_en and pec_en. These bits MUST be + * submitted by the first operation only. + */ + if (op_idx == 0 && flags & MLXBF_I2C_F_SMBUS_OPERATION) { + block_en = flags & MLXBF_I2C_F_SMBUS_BLOCK; + pec_en = flags & MLXBF_I2C_F_SMBUS_PEC; + } + + if (flags & MLXBF_I2C_F_WRITE) { + write_en = 1; + write_len += operation->length; + if (data_idx + operation->length > + MLXBF_I2C_MASTER_DATA_DESC_SIZE) { + ret = -ENOBUFS; + goto out_unlock; + } + memcpy(data_desc + data_idx, + operation->buffer, operation->length); + data_idx += operation->length; + } + /* + * We assume that read operations are performed only once per + * SMBus transaction. *TBD* protect this statement so it won't + * be executed twice? or return an error if we try to read more + * than once? + */ + if (flags & MLXBF_I2C_F_READ) { + read_en = 1; + /* Subtract 1 as required by HW. */ + read_len = operation->length - 1; + read_buf = operation->buffer; + } + } + + /* Set Master GW data descriptor. */ + data_len = write_len + 1; /* Add one byte of the slave address. */ + /* + * Note that data_len cannot be 0. Indeed, the slave address byte + * must be written to the data registers. + */ + mlxbf_i2c_smbus_write_data(priv, (const u8 *)data_desc, data_len, + MLXBF_I2C_MASTER_DATA_DESC_ADDR, true); + + if (write_en) { + ret = mlxbf_i2c_smbus_enable(priv, slave, write_len, block_en, + pec_en, 0); + if (ret) + goto out_unlock; + } + + if (read_en) { + /* Write slave address to Master GW data descriptor. */ + mlxbf_i2c_smbus_write_data(priv, (const u8 *)&addr, 1, + MLXBF_I2C_MASTER_DATA_DESC_ADDR, true); + ret = mlxbf_i2c_smbus_enable(priv, slave, read_len, block_en, + pec_en, 1); + if (!ret) { + /* Get Master GW data descriptor. */ + mlxbf_i2c_smbus_read_data(priv, data_desc, read_len + 1, + MLXBF_I2C_MASTER_DATA_DESC_ADDR, true); + + /* Get data from Master GW data descriptor. */ + memcpy(read_buf, data_desc, read_len + 1); + } + + /* + * After a read operation the SMBus FSM ps (present state) + * needs to be 'manually' reset. This should be removed in + * next tag integration. + */ + writel(MLXBF_I2C_SMBUS_MASTER_FSM_PS_STATE_MASK, + priv->mst->io + priv->chip->smbus_master_fsm_off); + } + +out_unlock: + mlxbf_i2c_smbus_master_unlock(priv); + + return ret; +} + +/* I2C SMBus protocols. */ + +static void +mlxbf_i2c_smbus_quick_command(struct mlxbf_i2c_smbus_request *request, + u8 read) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_1; + + request->operation[0].length = 0; + request->operation[0].flags = MLXBF_I2C_F_WRITE; + request->operation[0].flags |= read ? MLXBF_I2C_F_READ : 0; +} + +static void mlxbf_i2c_smbus_byte_func(struct mlxbf_i2c_smbus_request *request, + u8 *data, bool read, bool pec_check) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_1; + + request->operation[0].length = 1; + request->operation[0].length += pec_check; + + request->operation[0].flags = MLXBF_I2C_F_SMBUS_OPERATION; + request->operation[0].flags |= read ? + MLXBF_I2C_F_READ : MLXBF_I2C_F_WRITE; + request->operation[0].flags |= pec_check ? MLXBF_I2C_F_SMBUS_PEC : 0; + + request->operation[0].buffer = data; +} + +static void +mlxbf_i2c_smbus_data_byte_func(struct mlxbf_i2c_smbus_request *request, + u8 *command, u8 *data, bool read, bool pec_check) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_2; + + request->operation[0].length = 1; + request->operation[0].flags = + MLXBF_I2C_F_SMBUS_OPERATION | MLXBF_I2C_F_WRITE; + request->operation[0].flags |= pec_check ? MLXBF_I2C_F_SMBUS_PEC : 0; + request->operation[0].buffer = command; + + request->operation[1].length = 1; + request->operation[1].length += pec_check; + request->operation[1].flags = read ? + MLXBF_I2C_F_READ : MLXBF_I2C_F_WRITE; + request->operation[1].buffer = data; +} + +static void +mlxbf_i2c_smbus_data_word_func(struct mlxbf_i2c_smbus_request *request, + u8 *command, u8 *data, bool read, bool pec_check) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_2; + + request->operation[0].length = 1; + request->operation[0].flags = + MLXBF_I2C_F_SMBUS_OPERATION | MLXBF_I2C_F_WRITE; + request->operation[0].flags |= pec_check ? MLXBF_I2C_F_SMBUS_PEC : 0; + request->operation[0].buffer = command; + + request->operation[1].length = 2; + request->operation[1].length += pec_check; + request->operation[1].flags = read ? + MLXBF_I2C_F_READ : MLXBF_I2C_F_WRITE; + request->operation[1].buffer = data; +} + +static void +mlxbf_i2c_smbus_i2c_block_func(struct mlxbf_i2c_smbus_request *request, + u8 *command, u8 *data, u8 *data_len, bool read, + bool pec_check) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_2; + + request->operation[0].length = 1; + request->operation[0].flags = + MLXBF_I2C_F_SMBUS_OPERATION | MLXBF_I2C_F_WRITE; + request->operation[0].flags |= pec_check ? MLXBF_I2C_F_SMBUS_PEC : 0; + request->operation[0].buffer = command; + + /* + * As specified in the standard, the max number of bytes to read/write + * per block operation is 32 bytes. In Golan code, the controller can + * read up to 128 bytes and write up to 127 bytes. + */ + request->operation[1].length = + (*data_len + pec_check > I2C_SMBUS_BLOCK_MAX) ? + I2C_SMBUS_BLOCK_MAX : *data_len + pec_check; + request->operation[1].flags = read ? + MLXBF_I2C_F_READ : MLXBF_I2C_F_WRITE; + /* + * Skip the first data byte, which corresponds to the number of bytes + * to read/write. + */ + request->operation[1].buffer = data + 1; + + *data_len = request->operation[1].length; + + /* Set the number of byte to read. This will be used by userspace. */ + if (read) + data[0] = *data_len; +} + +static void mlxbf_i2c_smbus_block_func(struct mlxbf_i2c_smbus_request *request, + u8 *command, u8 *data, u8 *data_len, + bool read, bool pec_check) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_2; + + request->operation[0].length = 1; + request->operation[0].flags = + MLXBF_I2C_F_SMBUS_OPERATION | MLXBF_I2C_F_WRITE; + request->operation[0].flags |= MLXBF_I2C_F_SMBUS_BLOCK; + request->operation[0].flags |= pec_check ? MLXBF_I2C_F_SMBUS_PEC : 0; + request->operation[0].buffer = command; + + request->operation[1].length = + (*data_len + pec_check > I2C_SMBUS_BLOCK_MAX) ? + I2C_SMBUS_BLOCK_MAX : *data_len + pec_check; + request->operation[1].flags = read ? + MLXBF_I2C_F_READ : MLXBF_I2C_F_WRITE; + request->operation[1].buffer = data + 1; + + *data_len = request->operation[1].length; + + /* Set the number of bytes to read. This will be used by userspace. */ + if (read) + data[0] = *data_len; +} + +static void +mlxbf_i2c_smbus_process_call_func(struct mlxbf_i2c_smbus_request *request, + u8 *command, u8 *data, bool pec_check) +{ + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_3; + + request->operation[0].length = 1; + request->operation[0].flags = + MLXBF_I2C_F_SMBUS_OPERATION | MLXBF_I2C_F_WRITE; + request->operation[0].flags |= MLXBF_I2C_F_SMBUS_BLOCK; + request->operation[0].flags |= pec_check ? MLXBF_I2C_F_SMBUS_PEC : 0; + request->operation[0].buffer = command; + + request->operation[1].length = 2; + request->operation[1].flags = MLXBF_I2C_F_WRITE; + request->operation[1].buffer = data; + + request->operation[2].length = 3; + request->operation[2].flags = MLXBF_I2C_F_READ; + request->operation[2].buffer = data; +} + +static void +mlxbf_i2c_smbus_blk_process_call_func(struct mlxbf_i2c_smbus_request *request, + u8 *command, u8 *data, u8 *data_len, + bool pec_check) +{ + u32 length; + + request->operation_cnt = MLXBF_I2C_SMBUS_OP_CNT_3; + + request->operation[0].length = 1; + request->operation[0].flags = + MLXBF_I2C_F_SMBUS_OPERATION | MLXBF_I2C_F_WRITE; + request->operation[0].flags |= MLXBF_I2C_F_SMBUS_BLOCK; + request->operation[0].flags |= (pec_check) ? MLXBF_I2C_F_SMBUS_PEC : 0; + request->operation[0].buffer = command; + + length = (*data_len + pec_check > I2C_SMBUS_BLOCK_MAX) ? + I2C_SMBUS_BLOCK_MAX : *data_len + pec_check; + + request->operation[1].length = length - pec_check; + request->operation[1].flags = MLXBF_I2C_F_WRITE; + request->operation[1].buffer = data; + + request->operation[2].length = length; + request->operation[2].flags = MLXBF_I2C_F_READ; + request->operation[2].buffer = data; + + *data_len = length; /* including PEC byte. */ +} + +/* Initialization functions. */ + +static bool mlxbf_i2c_has_chip_type(struct mlxbf_i2c_priv *priv, u8 type) +{ + return priv->chip->type == type; +} + +static struct mlxbf_i2c_resource * +mlxbf_i2c_get_shared_resource(struct mlxbf_i2c_priv *priv, u8 type) +{ + const struct mlxbf_i2c_chip_info *chip = priv->chip; + struct mlxbf_i2c_resource *res; + u8 res_idx = 0; + + for (res_idx = 0; res_idx < MLXBF_I2C_SHARED_RES_MAX; res_idx++) { + res = chip->shared_res[res_idx]; + if (res && res->type == type) + return res; + } + + return NULL; +} + +static int mlxbf_i2c_init_resource(struct platform_device *pdev, + struct mlxbf_i2c_resource **res, + u8 type) +{ + struct mlxbf_i2c_resource *tmp_res; + struct device *dev = &pdev->dev; + + if (!res || *res || type >= MLXBF_I2C_END_RES) + return -EINVAL; + + tmp_res = devm_kzalloc(dev, sizeof(struct mlxbf_i2c_resource), + GFP_KERNEL); + if (!tmp_res) + return -ENOMEM; + + tmp_res->io = devm_platform_get_and_ioremap_resource(pdev, type, &tmp_res->params); + if (IS_ERR(tmp_res->io)) { + devm_kfree(dev, tmp_res); + return PTR_ERR(tmp_res->io); + } + + tmp_res->type = type; + + *res = tmp_res; + + return 0; +} + +static u32 mlxbf_i2c_get_ticks(struct mlxbf_i2c_priv *priv, u64 nanoseconds, + bool minimum) +{ + u64 frequency; + u32 ticks; + + /* + * Compute ticks as follow: + * + * Ticks + * Time = --------- x 10^9 => Ticks = Time x Frequency x 10^-9 + * Frequency + */ + frequency = priv->frequency; + ticks = (nanoseconds * frequency) / MLXBF_I2C_FREQUENCY_1GHZ; + /* + * The number of ticks is rounded down and if minimum is equal to 1 + * then add one tick. + */ + if (minimum) + ticks++; + + return ticks; +} + +static u32 mlxbf_i2c_set_timer(struct mlxbf_i2c_priv *priv, u64 nsec, bool opt, + u32 mask, u8 shift) +{ + u32 val = (mlxbf_i2c_get_ticks(priv, nsec, opt) & mask) << shift; + + return val; +} + +static void mlxbf_i2c_set_timings(struct mlxbf_i2c_priv *priv, + const struct mlxbf_i2c_timings *timings) +{ + u32 timer; + + timer = mlxbf_i2c_set_timer(priv, timings->scl_high, + false, MLXBF_I2C_MASK_16, + MLXBF_I2C_SHIFT_0); + timer |= mlxbf_i2c_set_timer(priv, timings->scl_low, + false, MLXBF_I2C_MASK_16, + MLXBF_I2C_SHIFT_16); + writel(timer, priv->timer->io + + MLXBF_I2C_SMBUS_TIMER_SCL_LOW_SCL_HIGH); + + timer = mlxbf_i2c_set_timer(priv, timings->sda_rise, false, + MLXBF_I2C_MASK_8, MLXBF_I2C_SHIFT_0); + timer |= mlxbf_i2c_set_timer(priv, timings->sda_fall, false, + MLXBF_I2C_MASK_8, MLXBF_I2C_SHIFT_8); + timer |= mlxbf_i2c_set_timer(priv, timings->scl_rise, false, + MLXBF_I2C_MASK_8, MLXBF_I2C_SHIFT_16); + timer |= mlxbf_i2c_set_timer(priv, timings->scl_fall, false, + MLXBF_I2C_MASK_8, MLXBF_I2C_SHIFT_24); + writel(timer, priv->timer->io + + MLXBF_I2C_SMBUS_TIMER_FALL_RISE_SPIKE); + + timer = mlxbf_i2c_set_timer(priv, timings->hold_start, true, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_0); + timer |= mlxbf_i2c_set_timer(priv, timings->hold_data, true, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_16); + writel(timer, priv->timer->io + MLXBF_I2C_SMBUS_TIMER_THOLD); + + timer = mlxbf_i2c_set_timer(priv, timings->setup_start, true, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_0); + timer |= mlxbf_i2c_set_timer(priv, timings->setup_stop, true, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_16); + writel(timer, priv->timer->io + + MLXBF_I2C_SMBUS_TIMER_TSETUP_START_STOP); + + timer = mlxbf_i2c_set_timer(priv, timings->setup_data, true, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_0); + writel(timer, priv->timer->io + MLXBF_I2C_SMBUS_TIMER_TSETUP_DATA); + + timer = mlxbf_i2c_set_timer(priv, timings->buf, false, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_0); + timer |= mlxbf_i2c_set_timer(priv, timings->thigh_max, false, + MLXBF_I2C_MASK_16, MLXBF_I2C_SHIFT_16); + writel(timer, priv->timer->io + MLXBF_I2C_SMBUS_THIGH_MAX_TBUF); + + timer = timings->timeout; + writel(timer, priv->timer->io + MLXBF_I2C_SMBUS_SCL_LOW_TIMEOUT); +} + +enum mlxbf_i2c_timings_config { + MLXBF_I2C_TIMING_CONFIG_100KHZ, + MLXBF_I2C_TIMING_CONFIG_400KHZ, + MLXBF_I2C_TIMING_CONFIG_1000KHZ, +}; + +/* + * Note that the mlxbf_i2c_timings->timeout value is not related to the + * bus frequency, it is impacted by the time it takes the driver to + * complete data transmission before transaction abort. + */ +static const struct mlxbf_i2c_timings mlxbf_i2c_timings[] = { + [MLXBF_I2C_TIMING_CONFIG_100KHZ] = { + .scl_high = 4810, + .scl_low = 5000, + .hold_start = 4000, + .setup_start = 4800, + .setup_stop = 4000, + .setup_data = 250, + .sda_rise = 50, + .sda_fall = 50, + .scl_rise = 50, + .scl_fall = 50, + .hold_data = 300, + .buf = 20000, + .thigh_max = 5000, + .timeout = 106500 + }, + [MLXBF_I2C_TIMING_CONFIG_400KHZ] = { + .scl_high = 1011, + .scl_low = 1300, + .hold_start = 600, + .setup_start = 700, + .setup_stop = 600, + .setup_data = 100, + .sda_rise = 50, + .sda_fall = 50, + .scl_rise = 50, + .scl_fall = 50, + .hold_data = 300, + .buf = 20000, + .thigh_max = 5000, + .timeout = 106500 + }, + [MLXBF_I2C_TIMING_CONFIG_1000KHZ] = { + .scl_high = 600, + .scl_low = 1300, + .hold_start = 600, + .setup_start = 600, + .setup_stop = 600, + .setup_data = 100, + .sda_rise = 50, + .sda_fall = 50, + .scl_rise = 50, + .scl_fall = 50, + .hold_data = 300, + .buf = 20000, + .thigh_max = 5000, + .timeout = 106500 + } +}; + +static int mlxbf_i2c_init_timings(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + enum mlxbf_i2c_timings_config config_idx; + struct device *dev = &pdev->dev; + u32 config_khz; + + int ret; + + ret = device_property_read_u32(dev, "clock-frequency", &config_khz); + if (ret < 0) + config_khz = I2C_MAX_STANDARD_MODE_FREQ; + + switch (config_khz) { + default: + /* Default settings is 100 KHz. */ + pr_warn("Illegal value %d: defaulting to 100 KHz\n", + config_khz); + fallthrough; + case I2C_MAX_STANDARD_MODE_FREQ: + config_idx = MLXBF_I2C_TIMING_CONFIG_100KHZ; + break; + + case I2C_MAX_FAST_MODE_FREQ: + config_idx = MLXBF_I2C_TIMING_CONFIG_400KHZ; + break; + + case I2C_MAX_FAST_MODE_PLUS_FREQ: + config_idx = MLXBF_I2C_TIMING_CONFIG_1000KHZ; + break; + } + + mlxbf_i2c_set_timings(priv, &mlxbf_i2c_timings[config_idx]); + + return 0; +} + +static int mlxbf_i2c_get_gpio(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *gpio_res; + struct device *dev = &pdev->dev; + struct resource *params; + resource_size_t size; + + gpio_res = mlxbf_i2c_get_shared_resource(priv, MLXBF_I2C_GPIO_RES); + if (!gpio_res) + return -EPERM; + + /* + * The GPIO region in TYU space is shared among I2C busses. + * This function MUST be serialized to avoid racing when + * claiming the memory region and/or setting up the GPIO. + */ + lockdep_assert_held(gpio_res->lock); + + /* Check whether the memory map exist. */ + if (gpio_res->io) + return 0; + + params = gpio_res->params; + size = resource_size(params); + + if (!devm_request_mem_region(dev, params->start, size, params->name)) + return -EFAULT; + + gpio_res->io = devm_ioremap(dev, params->start, size); + if (!gpio_res->io) { + devm_release_mem_region(dev, params->start, size); + return -ENOMEM; + } + + return 0; +} + +static int mlxbf_i2c_release_gpio(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *gpio_res; + struct device *dev = &pdev->dev; + struct resource *params; + + gpio_res = mlxbf_i2c_get_shared_resource(priv, MLXBF_I2C_GPIO_RES); + if (!gpio_res) + return 0; + + mutex_lock(gpio_res->lock); + + if (gpio_res->io) { + /* Release the GPIO resource. */ + params = gpio_res->params; + devm_iounmap(dev, gpio_res->io); + devm_release_mem_region(dev, params->start, + resource_size(params)); + } + + mutex_unlock(gpio_res->lock); + + return 0; +} + +static int mlxbf_i2c_get_corepll(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *corepll_res; + struct device *dev = &pdev->dev; + struct resource *params; + resource_size_t size; + + corepll_res = mlxbf_i2c_get_shared_resource(priv, + MLXBF_I2C_COREPLL_RES); + if (!corepll_res) + return -EPERM; + + /* + * The COREPLL region in TYU space is shared among I2C busses. + * This function MUST be serialized to avoid racing when + * claiming the memory region. + */ + lockdep_assert_held(corepll_res->lock); + + /* Check whether the memory map exist. */ + if (corepll_res->io) + return 0; + + params = corepll_res->params; + size = resource_size(params); + + if (!devm_request_mem_region(dev, params->start, size, params->name)) + return -EFAULT; + + corepll_res->io = devm_ioremap(dev, params->start, size); + if (!corepll_res->io) { + devm_release_mem_region(dev, params->start, size); + return -ENOMEM; + } + + return 0; +} + +static int mlxbf_i2c_release_corepll(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *corepll_res; + struct device *dev = &pdev->dev; + struct resource *params; + + corepll_res = mlxbf_i2c_get_shared_resource(priv, + MLXBF_I2C_COREPLL_RES); + + mutex_lock(corepll_res->lock); + + if (corepll_res->io) { + /* Release the CorePLL resource. */ + params = corepll_res->params; + devm_iounmap(dev, corepll_res->io); + devm_release_mem_region(dev, params->start, + resource_size(params)); + } + + mutex_unlock(corepll_res->lock); + + return 0; +} + +static int mlxbf_i2c_init_master(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *gpio_res; + struct device *dev = &pdev->dev; + u32 config_reg; + int ret; + + /* This configuration is only needed for BlueField 1. */ + if (!mlxbf_i2c_has_chip_type(priv, MLXBF_I2C_CHIP_TYPE_1)) + return 0; + + gpio_res = mlxbf_i2c_get_shared_resource(priv, MLXBF_I2C_GPIO_RES); + if (!gpio_res) + return -EPERM; + + /* + * The GPIO region in TYU space is shared among I2C busses. + * This function MUST be serialized to avoid racing when + * claiming the memory region and/or setting up the GPIO. + */ + + mutex_lock(gpio_res->lock); + + ret = mlxbf_i2c_get_gpio(pdev, priv); + if (ret < 0) { + dev_err(dev, "Failed to get gpio resource"); + mutex_unlock(gpio_res->lock); + return ret; + } + + /* + * TYU - Configuration for GPIO pins. Those pins must be asserted in + * MLXBF_I2C_GPIO_0_FUNC_EN_0, i.e. GPIO 0 is controlled by HW, and must + * be reset in MLXBF_I2C_GPIO_0_FORCE_OE_EN, i.e. GPIO_OE will be driven + * instead of HW_OE. + * For now, we do not reset the GPIO state when the driver is removed. + * First, it is not necessary to disable the bus since we are using + * the same busses. Then, some busses might be shared among Linux and + * platform firmware; disabling the bus might compromise the system + * functionality. + */ + config_reg = readl(gpio_res->io + MLXBF_I2C_GPIO_0_FUNC_EN_0); + config_reg = MLXBF_I2C_GPIO_SMBUS_GW_ASSERT_PINS(priv->bus, + config_reg); + writel(config_reg, gpio_res->io + MLXBF_I2C_GPIO_0_FUNC_EN_0); + + config_reg = readl(gpio_res->io + MLXBF_I2C_GPIO_0_FORCE_OE_EN); + config_reg = MLXBF_I2C_GPIO_SMBUS_GW_RESET_PINS(priv->bus, + config_reg); + writel(config_reg, gpio_res->io + MLXBF_I2C_GPIO_0_FORCE_OE_EN); + + mutex_unlock(gpio_res->lock); + + return 0; +} + +static u64 mlxbf_i2c_calculate_freq_from_tyu(struct mlxbf_i2c_resource *corepll_res) +{ + u64 core_frequency; + u8 core_od, core_r; + u32 corepll_val; + u16 core_f; + + corepll_val = readl(corepll_res->io + MLXBF_I2C_CORE_PLL_REG1); + + /* Get Core PLL configuration bits. */ + core_f = FIELD_GET(MLXBF_I2C_COREPLL_CORE_F_TYU_MASK, corepll_val); + core_od = FIELD_GET(MLXBF_I2C_COREPLL_CORE_OD_TYU_MASK, corepll_val); + core_r = FIELD_GET(MLXBF_I2C_COREPLL_CORE_R_TYU_MASK, corepll_val); + + /* + * Compute PLL output frequency as follow: + * + * CORE_F + 1 + * PLL_OUT_FREQ = PLL_IN_FREQ * ---------------------------- + * (CORE_R + 1) * (CORE_OD + 1) + * + * Where PLL_OUT_FREQ and PLL_IN_FREQ refer to CoreFrequency + * and PadFrequency, respectively. + */ + core_frequency = MLXBF_I2C_PLL_IN_FREQ * (++core_f); + core_frequency /= (++core_r) * (++core_od); + + return core_frequency; +} + +static u64 mlxbf_i2c_calculate_freq_from_yu(struct mlxbf_i2c_resource *corepll_res) +{ + u32 corepll_reg1_val, corepll_reg2_val; + u64 corepll_frequency; + u8 core_od, core_r; + u32 core_f; + + corepll_reg1_val = readl(corepll_res->io + MLXBF_I2C_CORE_PLL_REG1); + corepll_reg2_val = readl(corepll_res->io + MLXBF_I2C_CORE_PLL_REG2); + + /* Get Core PLL configuration bits */ + core_f = FIELD_GET(MLXBF_I2C_COREPLL_CORE_F_YU_MASK, corepll_reg1_val); + core_r = FIELD_GET(MLXBF_I2C_COREPLL_CORE_R_YU_MASK, corepll_reg1_val); + core_od = FIELD_GET(MLXBF_I2C_COREPLL_CORE_OD_YU_MASK, corepll_reg2_val); + + /* + * Compute PLL output frequency as follow: + * + * CORE_F / 16384 + * PLL_OUT_FREQ = PLL_IN_FREQ * ---------------------------- + * (CORE_R + 1) * (CORE_OD + 1) + * + * Where PLL_OUT_FREQ and PLL_IN_FREQ refer to CoreFrequency + * and PadFrequency, respectively. + */ + corepll_frequency = (MLXBF_I2C_PLL_IN_FREQ * core_f) / MLNXBF_I2C_COREPLL_CONST; + corepll_frequency /= (++core_r) * (++core_od); + + return corepll_frequency; +} + +static int mlxbf_i2c_calculate_corepll_freq(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + const struct mlxbf_i2c_chip_info *chip = priv->chip; + struct mlxbf_i2c_resource *corepll_res; + struct device *dev = &pdev->dev; + u64 *freq = &priv->frequency; + int ret; + + corepll_res = mlxbf_i2c_get_shared_resource(priv, + MLXBF_I2C_COREPLL_RES); + if (!corepll_res) + return -EPERM; + + /* + * First, check whether the TYU core Clock frequency is set. + * The TYU core frequency is the same for all I2C busses; when + * the first device gets probed the frequency is determined and + * stored into a globally visible variable. So, first of all, + * check whether the frequency is already set. Here, we assume + * that the frequency is expected to be greater than 0. + */ + mutex_lock(corepll_res->lock); + if (!mlxbf_i2c_corepll_frequency) { + if (!chip->calculate_freq) { + mutex_unlock(corepll_res->lock); + return -EPERM; + } + + ret = mlxbf_i2c_get_corepll(pdev, priv); + if (ret < 0) { + dev_err(dev, "Failed to get corePLL resource"); + mutex_unlock(corepll_res->lock); + return ret; + } + + mlxbf_i2c_corepll_frequency = chip->calculate_freq(corepll_res); + } + mutex_unlock(corepll_res->lock); + + *freq = mlxbf_i2c_corepll_frequency; + + return 0; +} + +static int mlxbf_i2c_slave_enable(struct mlxbf_i2c_priv *priv, + struct i2c_client *slave) +{ + u8 reg, reg_cnt, byte, addr_tmp; + u32 slave_reg, slave_reg_tmp; + + if (!priv) + return -EPERM; + + reg_cnt = MLXBF_I2C_SMBUS_SLAVE_ADDR_CNT >> 2; + + /* + * Read the slave registers. There are 4 * 32-bit slave registers. + * Each slave register can hold up to 4 * 8-bit slave configuration: + * 1) A 7-bit address + * 2) And a status bit (1 if enabled, 0 if not). + * Look for the next available slave register slot. + */ + for (reg = 0; reg < reg_cnt; reg++) { + slave_reg = readl(priv->slv->io + + MLXBF_I2C_SMBUS_SLAVE_ADDR_CFG + reg * 0x4); + /* + * Each register holds 4 slave addresses. So, we have to keep + * the byte order consistent with the value read in order to + * update the register correctly, if needed. + */ + slave_reg_tmp = slave_reg; + for (byte = 0; byte < 4; byte++) { + addr_tmp = slave_reg_tmp & GENMASK(7, 0); + + /* + * If an enable bit is not set in the + * MLXBF_I2C_SMBUS_SLAVE_ADDR_CFG register, then the + * slave address slot associated with that bit is + * free. So set the enable bit and write the + * slave address bits. + */ + if (!(addr_tmp & MLXBF_I2C_SMBUS_SLAVE_ADDR_EN_BIT)) { + slave_reg &= ~(MLXBF_I2C_SMBUS_SLAVE_ADDR_MASK << (byte * 8)); + slave_reg |= (slave->addr << (byte * 8)); + slave_reg |= MLXBF_I2C_SMBUS_SLAVE_ADDR_EN_BIT << (byte * 8); + writel(slave_reg, priv->slv->io + + MLXBF_I2C_SMBUS_SLAVE_ADDR_CFG + + (reg * 0x4)); + + /* + * Set the slave at the corresponding index. + */ + priv->slave[(reg * 4) + byte] = slave; + + return 0; + } + + /* Parse next byte. */ + slave_reg_tmp >>= 8; + } + } + + return -EBUSY; +} + +static int mlxbf_i2c_slave_disable(struct mlxbf_i2c_priv *priv, u8 addr) +{ + u8 addr_tmp, reg, reg_cnt, byte; + u32 slave_reg, slave_reg_tmp; + + reg_cnt = MLXBF_I2C_SMBUS_SLAVE_ADDR_CNT >> 2; + + /* + * Read the slave registers. There are 4 * 32-bit slave registers. + * Each slave register can hold up to 4 * 8-bit slave configuration: + * 1) A 7-bit address + * 2) And a status bit (1 if enabled, 0 if not). + * Check if addr is present in the registers. + */ + for (reg = 0; reg < reg_cnt; reg++) { + slave_reg = readl(priv->slv->io + + MLXBF_I2C_SMBUS_SLAVE_ADDR_CFG + reg * 0x4); + + /* Check whether the address slots are empty. */ + if (!slave_reg) + continue; + + /* + * Check if addr matches any of the 4 slave addresses + * in the register. + */ + slave_reg_tmp = slave_reg; + for (byte = 0; byte < 4; byte++) { + addr_tmp = slave_reg_tmp & MLXBF_I2C_SMBUS_SLAVE_ADDR_MASK; + /* + * Parse slave address bytes and check whether the + * slave address already exists. + */ + if (addr_tmp == addr) { + /* Clear the slave address slot. */ + slave_reg &= ~(GENMASK(7, 0) << (byte * 8)); + writel(slave_reg, priv->slv->io + + MLXBF_I2C_SMBUS_SLAVE_ADDR_CFG + + (reg * 0x4)); + /* Free slave at the corresponding index */ + priv->slave[(reg * 4) + byte] = NULL; + + return 0; + } + + /* Parse next byte. */ + slave_reg_tmp >>= 8; + } + } + + return -ENXIO; +} + +static int mlxbf_i2c_init_coalesce(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *coalesce_res; + struct resource *params; + resource_size_t size; + int ret = 0; + + /* + * Unlike BlueField-1 platform, the coalesce registers is a dedicated + * resource in the next generations of BlueField. + */ + if (mlxbf_i2c_has_chip_type(priv, MLXBF_I2C_CHIP_TYPE_1)) { + coalesce_res = mlxbf_i2c_get_shared_resource(priv, + MLXBF_I2C_COALESCE_RES); + if (!coalesce_res) + return -EPERM; + + /* + * The Cause Coalesce group in TYU space is shared among + * I2C busses. This function MUST be serialized to avoid + * racing when claiming the memory region. + */ + lockdep_assert_held(mlxbf_i2c_gpio_res->lock); + + /* Check whether the memory map exist. */ + if (coalesce_res->io) { + priv->coalesce = coalesce_res; + return 0; + } + + params = coalesce_res->params; + size = resource_size(params); + + if (!request_mem_region(params->start, size, params->name)) + return -EFAULT; + + coalesce_res->io = ioremap(params->start, size); + if (!coalesce_res->io) { + release_mem_region(params->start, size); + return -ENOMEM; + } + + priv->coalesce = coalesce_res; + + } else { + ret = mlxbf_i2c_init_resource(pdev, &priv->coalesce, + MLXBF_I2C_COALESCE_RES); + } + + return ret; +} + +static int mlxbf_i2c_release_coalesce(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct mlxbf_i2c_resource *coalesce_res; + struct device *dev = &pdev->dev; + struct resource *params; + resource_size_t size; + + coalesce_res = priv->coalesce; + + if (coalesce_res->io) { + params = coalesce_res->params; + size = resource_size(params); + if (mlxbf_i2c_has_chip_type(priv, MLXBF_I2C_CHIP_TYPE_1)) { + mutex_lock(coalesce_res->lock); + iounmap(coalesce_res->io); + release_mem_region(params->start, size); + mutex_unlock(coalesce_res->lock); + } else { + devm_release_mem_region(dev, params->start, size); + } + } + + return 0; +} + +static int mlxbf_i2c_init_slave(struct platform_device *pdev, + struct mlxbf_i2c_priv *priv) +{ + struct device *dev = &pdev->dev; + u32 int_reg; + int ret; + + /* Reset FSM. */ + writel(0, priv->slv->io + MLXBF_I2C_SMBUS_SLAVE_FSM); + + /* + * Enable slave cause interrupt bits. Drive + * MLXBF_I2C_CAUSE_READ_WAIT_FW_RESPONSE and + * MLXBF_I2C_CAUSE_WRITE_SUCCESS, these are enabled when an external + * masters issue a Read and Write, respectively. But, clear all + * interrupts first. + */ + writel(~0, priv->slv_cause->io + MLXBF_I2C_CAUSE_OR_CLEAR); + int_reg = MLXBF_I2C_CAUSE_READ_WAIT_FW_RESPONSE; + int_reg |= MLXBF_I2C_CAUSE_WRITE_SUCCESS; + writel(int_reg, priv->slv_cause->io + MLXBF_I2C_CAUSE_OR_EVTEN0); + + /* Finally, set the 'ready' bit to start handling transactions. */ + writel(0x1, priv->slv->io + MLXBF_I2C_SMBUS_SLAVE_READY); + + /* Initialize the cause coalesce resource. */ + ret = mlxbf_i2c_init_coalesce(pdev, priv); + if (ret < 0) { + dev_err(dev, "failed to initialize cause coalesce\n"); + return ret; + } + + return 0; +} + +static bool mlxbf_i2c_has_coalesce(struct mlxbf_i2c_priv *priv, bool *read, + bool *write) +{ + const struct mlxbf_i2c_chip_info *chip = priv->chip; + u32 coalesce0_reg, cause_reg; + u8 slave_shift, is_set; + + *write = false; + *read = false; + + slave_shift = chip->type != MLXBF_I2C_CHIP_TYPE_1 ? + MLXBF_I2C_CAUSE_YU_SLAVE_BIT : + priv->bus + MLXBF_I2C_CAUSE_TYU_SLAVE_BIT; + + coalesce0_reg = readl(priv->coalesce->io + MLXBF_I2C_CAUSE_COALESCE_0); + is_set = coalesce0_reg & (1 << slave_shift); + + if (!is_set) + return false; + + /* Check the source of the interrupt, i.e. whether a Read or Write. */ + cause_reg = readl(priv->slv_cause->io + MLXBF_I2C_CAUSE_ARBITER); + if (cause_reg & MLXBF_I2C_CAUSE_READ_WAIT_FW_RESPONSE) + *read = true; + else if (cause_reg & MLXBF_I2C_CAUSE_WRITE_SUCCESS) + *write = true; + + /* Clear cause bits. */ + writel(~0x0, priv->slv_cause->io + MLXBF_I2C_CAUSE_OR_CLEAR); + + return true; +} + +static bool mlxbf_i2c_slave_wait_for_idle(struct mlxbf_i2c_priv *priv, + u32 timeout) +{ + u32 mask = MLXBF_I2C_CAUSE_S_GW_BUSY_FALL; + u32 addr = MLXBF_I2C_CAUSE_ARBITER; + + if (mlxbf_i2c_poll(priv->slv_cause->io, addr, mask, false, timeout)) + return true; + + return false; +} + +static struct i2c_client *mlxbf_i2c_get_slave_from_addr( + struct mlxbf_i2c_priv *priv, u8 addr) +{ + int i; + + for (i = 0; i < MLXBF_I2C_SMBUS_SLAVE_ADDR_CNT; i++) { + if (!priv->slave[i]) + continue; + + if (priv->slave[i]->addr == addr) + return priv->slave[i]; + } + + return NULL; +} + +/* + * Send byte to 'external' smbus master. This function is executed when + * an external smbus master wants to read data from the BlueField. + */ +static int mlxbf_i2c_irq_send(struct mlxbf_i2c_priv *priv, u8 recv_bytes) +{ + u8 data_desc[MLXBF_I2C_SLAVE_DATA_DESC_SIZE] = { 0 }; + u8 write_size, pec_en, addr, value, byte_cnt; + struct i2c_client *slave; + u32 control32, data32; + int ret = 0; + + /* + * Read the first byte received from the external master to + * determine the slave address. This byte is located in the + * first data descriptor register of the slave GW. + */ + data32 = ioread32be(priv->slv->io + + MLXBF_I2C_SLAVE_DATA_DESC_ADDR); + addr = (data32 & GENMASK(7, 0)) >> 1; + + /* + * Check if the slave address received in the data descriptor register + * matches any of the slave addresses registered. If there is a match, + * set the slave. + */ + slave = mlxbf_i2c_get_slave_from_addr(priv, addr); + if (!slave) { + ret = -ENXIO; + goto clear_csr; + } + + /* + * An I2C read can consist of a WRITE bit transaction followed by + * a READ bit transaction. Indeed, slave devices often expect + * the slave address to be followed by the internal address. + * So, write the internal address byte first, and then, send the + * requested data to the master. + */ + if (recv_bytes > 1) { + i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value); + value = (data32 >> 8) & GENMASK(7, 0); + ret = i2c_slave_event(slave, I2C_SLAVE_WRITE_RECEIVED, + &value); + i2c_slave_event(slave, I2C_SLAVE_STOP, &value); + + if (ret < 0) + goto clear_csr; + } + + /* + * Send data to the master. Currently, the driver supports + * READ_BYTE, READ_WORD and BLOCK READ protocols. The + * hardware can send up to 128 bytes per transfer which is + * the total size of the data registers. + */ + i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value); + + for (byte_cnt = 0; byte_cnt < MLXBF_I2C_SLAVE_DATA_DESC_SIZE; byte_cnt++) { + data_desc[byte_cnt] = value; + i2c_slave_event(slave, I2C_SLAVE_READ_PROCESSED, &value); + } + + /* Send a stop condition to the backend. */ + i2c_slave_event(slave, I2C_SLAVE_STOP, &value); + + /* Set the number of bytes to write to master. */ + write_size = (byte_cnt - 1) & 0x7f; + + /* Write data to Slave GW data descriptor. */ + mlxbf_i2c_smbus_write_data(priv, data_desc, byte_cnt, + MLXBF_I2C_SLAVE_DATA_DESC_ADDR, false); + + pec_en = 0; /* Disable PEC since it is not supported. */ + + /* Prepare control word. */ + control32 = MLXBF_I2C_SLAVE_ENABLE; + control32 |= rol32(write_size, MLXBF_I2C_SLAVE_WRITE_BYTES_SHIFT); + control32 |= rol32(pec_en, MLXBF_I2C_SLAVE_SEND_PEC_SHIFT); + + writel(control32, priv->slv->io + MLXBF_I2C_SMBUS_SLAVE_GW); + + /* + * Wait until the transfer is completed; the driver will wait + * until the GW is idle, a cause will rise on fall of GW busy. + */ + mlxbf_i2c_slave_wait_for_idle(priv, MLXBF_I2C_SMBUS_TIMEOUT); + +clear_csr: + /* Release the Slave GW. */ + writel(0x0, priv->slv->io + MLXBF_I2C_SMBUS_SLAVE_RS_MASTER_BYTES); + writel(0x0, priv->slv->io + MLXBF_I2C_SMBUS_SLAVE_PEC); + writel(0x1, priv->slv->io + MLXBF_I2C_SMBUS_SLAVE_READY); + + return ret; +} + +/* + * Receive bytes from 'external' smbus master. This function is executed when + * an external smbus master wants to write data to the BlueField. + */ +static int mlxbf_i2c_irq_recv(struct mlxbf_i2c_priv *priv, u8 recv_bytes) +{ + u8 data_desc[MLXBF_I2C_SLAVE_DATA_DESC_SIZE] = { 0 }; + struct i2c_client *slave; + u8 value, byte, addr; + int ret = 0; + + /* Read data from Slave GW data descriptor. */ + mlxbf_i2c_smbus_read_data(priv, data_desc, recv_bytes, + MLXBF_I2C_SLAVE_DATA_DESC_ADDR, false); + addr = data_desc[0] >> 1; + + /* + * Check if the slave address received in the data descriptor register + * matches any of the slave addresses registered. + */ + slave = mlxbf_i2c_get_slave_from_addr(priv, addr); + if (!slave) { + ret = -EINVAL; + goto clear_csr; + } + + /* + * Notify the slave backend that an smbus master wants to write data + * to the BlueField. + */ + i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value); + + /* Send the received data to the slave backend. */ + for (byte = 1; byte < recv_bytes; byte++) { + value = data_desc[byte]; + ret = i2c_slave_event(slave, I2C_SLAVE_WRITE_RECEIVED, + &value); + if (ret < 0) + break; + } + + /* + * Send a stop event to the slave backend, to signal + * the end of the write transactions. + */ + i2c_slave_event(slave, I2C_SLAVE_STOP, &value); + +clear_csr: + /* Release the Slave GW. */ + writel(0x0, priv->slv->io + MLXBF_I2C_SMBUS_SLAVE_RS_MASTER_BYTES); + writel(0x0, priv->slv->io + MLXBF_I2C_SMBUS_SLAVE_PEC); + writel(0x1, priv->slv->io + MLXBF_I2C_SMBUS_SLAVE_READY); + + return ret; +} + +static irqreturn_t mlxbf_i2c_irq(int irq, void *ptr) +{ + struct mlxbf_i2c_priv *priv = ptr; + bool read, write, irq_is_set; + u32 rw_bytes_reg; + u8 recv_bytes; + + /* + * Read TYU interrupt register and determine the source of the + * interrupt. Based on the source of the interrupt one of the + * following actions are performed: + * - Receive data and send response to master. + * - Send data and release slave GW. + * + * Handle read/write transaction only. CRmaster and Iarp requests + * are ignored for now. + */ + irq_is_set = mlxbf_i2c_has_coalesce(priv, &read, &write); + if (!irq_is_set || (!read && !write)) { + /* Nothing to do here, interrupt was not from this device. */ + return IRQ_NONE; + } + + /* + * The MLXBF_I2C_SMBUS_SLAVE_RS_MASTER_BYTES includes the number of + * bytes from/to master. These are defined by 8-bits each. If the lower + * 8 bits are set, then the master expect to read N bytes from the + * slave, if the higher 8 bits are sent then the slave expect N bytes + * from the master. + */ + rw_bytes_reg = readl(priv->slv->io + + MLXBF_I2C_SMBUS_SLAVE_RS_MASTER_BYTES); + recv_bytes = (rw_bytes_reg >> 8) & GENMASK(7, 0); + + /* + * For now, the slave supports 128 bytes transfer. Discard remaining + * data bytes if the master wrote more than + * MLXBF_I2C_SLAVE_DATA_DESC_SIZE, i.e, the actual size of the slave + * data descriptor. + * + * Note that we will never expect to transfer more than 128 bytes; as + * specified in the SMBus standard, block transactions cannot exceed + * 32 bytes. + */ + recv_bytes = recv_bytes > MLXBF_I2C_SLAVE_DATA_DESC_SIZE ? + MLXBF_I2C_SLAVE_DATA_DESC_SIZE : recv_bytes; + + if (read) + mlxbf_i2c_irq_send(priv, recv_bytes); + else + mlxbf_i2c_irq_recv(priv, recv_bytes); + + return IRQ_HANDLED; +} + +/* Return negative errno on error. */ +static s32 mlxbf_i2c_smbus_xfer(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + struct mlxbf_i2c_smbus_request request = { 0 }; + struct mlxbf_i2c_priv *priv; + bool read, pec; + u8 byte_cnt; + + request.slave = addr; + + read = (read_write == I2C_SMBUS_READ); + pec = flags & I2C_FUNC_SMBUS_PEC; + + switch (size) { + case I2C_SMBUS_QUICK: + mlxbf_i2c_smbus_quick_command(&request, read); + dev_dbg(&adap->dev, "smbus quick, slave 0x%02x\n", addr); + break; + + case I2C_SMBUS_BYTE: + mlxbf_i2c_smbus_byte_func(&request, + read ? &data->byte : &command, read, + pec); + dev_dbg(&adap->dev, "smbus %s byte, slave 0x%02x.\n", + read ? "read" : "write", addr); + break; + + case I2C_SMBUS_BYTE_DATA: + mlxbf_i2c_smbus_data_byte_func(&request, &command, &data->byte, + read, pec); + dev_dbg(&adap->dev, "smbus %s byte data at 0x%02x, slave 0x%02x.\n", + read ? "read" : "write", command, addr); + break; + + case I2C_SMBUS_WORD_DATA: + mlxbf_i2c_smbus_data_word_func(&request, &command, + (u8 *)&data->word, read, pec); + dev_dbg(&adap->dev, "smbus %s word data at 0x%02x, slave 0x%02x.\n", + read ? "read" : "write", command, addr); + break; + + case I2C_SMBUS_I2C_BLOCK_DATA: + byte_cnt = data->block[0]; + mlxbf_i2c_smbus_i2c_block_func(&request, &command, data->block, + &byte_cnt, read, pec); + dev_dbg(&adap->dev, "i2c %s block data, %d bytes at 0x%02x, slave 0x%02x.\n", + read ? "read" : "write", byte_cnt, command, addr); + break; + + case I2C_SMBUS_BLOCK_DATA: + byte_cnt = read ? I2C_SMBUS_BLOCK_MAX : data->block[0]; + mlxbf_i2c_smbus_block_func(&request, &command, data->block, + &byte_cnt, read, pec); + dev_dbg(&adap->dev, "smbus %s block data, %d bytes at 0x%02x, slave 0x%02x.\n", + read ? "read" : "write", byte_cnt, command, addr); + break; + + case I2C_FUNC_SMBUS_PROC_CALL: + mlxbf_i2c_smbus_process_call_func(&request, &command, + (u8 *)&data->word, pec); + dev_dbg(&adap->dev, "process call, wr/rd at 0x%02x, slave 0x%02x.\n", + command, addr); + break; + + case I2C_FUNC_SMBUS_BLOCK_PROC_CALL: + byte_cnt = data->block[0]; + mlxbf_i2c_smbus_blk_process_call_func(&request, &command, + data->block, &byte_cnt, + pec); + dev_dbg(&adap->dev, "block process call, wr/rd %d bytes, slave 0x%02x.\n", + byte_cnt, addr); + break; + + default: + dev_dbg(&adap->dev, "Unsupported I2C/SMBus command %d\n", + size); + return -EOPNOTSUPP; + } + + priv = i2c_get_adapdata(adap); + + return mlxbf_i2c_smbus_start_transaction(priv, &request); +} + +static int mlxbf_i2c_reg_slave(struct i2c_client *slave) +{ + struct mlxbf_i2c_priv *priv = i2c_get_adapdata(slave->adapter); + struct device *dev = &slave->dev; + int ret; + + /* + * Do not support ten bit chip address and do not use Packet Error + * Checking (PEC). + */ + if (slave->flags & (I2C_CLIENT_TEN | I2C_CLIENT_PEC)) { + dev_err(dev, "SMBus PEC and 10 bit address not supported\n"); + return -EAFNOSUPPORT; + } + + ret = mlxbf_i2c_slave_enable(priv, slave); + if (ret) + dev_err(dev, "Surpassed max number of registered slaves allowed\n"); + + return 0; +} + +static int mlxbf_i2c_unreg_slave(struct i2c_client *slave) +{ + struct mlxbf_i2c_priv *priv = i2c_get_adapdata(slave->adapter); + struct device *dev = &slave->dev; + int ret; + + /* + * Unregister slave by: + * 1) Disabling the slave address in hardware + * 2) Freeing priv->slave at the corresponding index + */ + ret = mlxbf_i2c_slave_disable(priv, slave->addr); + if (ret) + dev_err(dev, "Unable to find slave 0x%x\n", slave->addr); + + return ret; +} + +static u32 mlxbf_i2c_functionality(struct i2c_adapter *adap) +{ + return MLXBF_I2C_FUNC_ALL; +} + +static struct mlxbf_i2c_chip_info mlxbf_i2c_chip[] = { + [MLXBF_I2C_CHIP_TYPE_1] = { + .type = MLXBF_I2C_CHIP_TYPE_1, + .shared_res = { + [0] = &mlxbf_i2c_coalesce_res[MLXBF_I2C_CHIP_TYPE_1], + [1] = &mlxbf_i2c_corepll_res[MLXBF_I2C_CHIP_TYPE_1], + [2] = &mlxbf_i2c_gpio_res[MLXBF_I2C_CHIP_TYPE_1] + }, + .calculate_freq = mlxbf_i2c_calculate_freq_from_tyu, + .smbus_master_rs_bytes_off = MLXBF_I2C_YU_SMBUS_RS_BYTES, + .smbus_master_fsm_off = MLXBF_I2C_YU_SMBUS_MASTER_FSM + }, + [MLXBF_I2C_CHIP_TYPE_2] = { + .type = MLXBF_I2C_CHIP_TYPE_2, + .shared_res = { + [0] = &mlxbf_i2c_corepll_res[MLXBF_I2C_CHIP_TYPE_2] + }, + .calculate_freq = mlxbf_i2c_calculate_freq_from_yu, + .smbus_master_rs_bytes_off = MLXBF_I2C_YU_SMBUS_RS_BYTES, + .smbus_master_fsm_off = MLXBF_I2C_YU_SMBUS_MASTER_FSM + }, + [MLXBF_I2C_CHIP_TYPE_3] = { + .type = MLXBF_I2C_CHIP_TYPE_3, + .shared_res = { + [0] = &mlxbf_i2c_corepll_res[MLXBF_I2C_CHIP_TYPE_3] + }, + .calculate_freq = mlxbf_i2c_calculate_freq_from_yu, + .smbus_master_rs_bytes_off = MLXBF_I2C_RSH_YU_SMBUS_RS_BYTES, + .smbus_master_fsm_off = MLXBF_I2C_RSH_YU_SMBUS_MASTER_FSM + } +}; + +static const struct i2c_algorithm mlxbf_i2c_algo = { + .smbus_xfer = mlxbf_i2c_smbus_xfer, + .functionality = mlxbf_i2c_functionality, + .reg_slave = mlxbf_i2c_reg_slave, + .unreg_slave = mlxbf_i2c_unreg_slave, +}; + +static struct i2c_adapter_quirks mlxbf_i2c_quirks = { + .max_read_len = MLXBF_I2C_MASTER_DATA_R_LENGTH, + .max_write_len = MLXBF_I2C_MASTER_DATA_W_LENGTH, +}; + +static const struct acpi_device_id mlxbf_i2c_acpi_ids[] = { + { "MLNXBF03", (kernel_ulong_t)&mlxbf_i2c_chip[MLXBF_I2C_CHIP_TYPE_1] }, + { "MLNXBF23", (kernel_ulong_t)&mlxbf_i2c_chip[MLXBF_I2C_CHIP_TYPE_2] }, + { "MLNXBF31", (kernel_ulong_t)&mlxbf_i2c_chip[MLXBF_I2C_CHIP_TYPE_3] }, + {}, +}; + +MODULE_DEVICE_TABLE(acpi, mlxbf_i2c_acpi_ids); + +static int mlxbf_i2c_acpi_probe(struct device *dev, struct mlxbf_i2c_priv *priv) +{ + const struct acpi_device_id *aid; + u64 bus_id; + int ret; + + if (acpi_disabled) + return -ENOENT; + + aid = acpi_match_device(mlxbf_i2c_acpi_ids, dev); + if (!aid) + return -ENODEV; + + priv->chip = (struct mlxbf_i2c_chip_info *)aid->driver_data; + + ret = acpi_dev_uid_to_integer(ACPI_COMPANION(dev), &bus_id); + if (ret) { + dev_err(dev, "Cannot retrieve UID\n"); + return ret; + } + + priv->bus = bus_id; + + return 0; +} + +static int mlxbf_i2c_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct mlxbf_i2c_priv *priv; + struct i2c_adapter *adap; + u32 resource_version; + int irq, ret; + + priv = devm_kzalloc(dev, sizeof(struct mlxbf_i2c_priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + ret = mlxbf_i2c_acpi_probe(dev, priv); + if (ret < 0) + return ret; + + /* This property allows the driver to stay backward compatible with older + * ACPI tables. + * Starting BlueField-3 SoC, the "smbus" resource was broken down into 3 + * separate resources "timer", "master" and "slave". + */ + if (device_property_read_u32(dev, "resource_version", &resource_version)) + resource_version = 0; + + priv->resource_version = resource_version; + + if (priv->chip->type < MLXBF_I2C_CHIP_TYPE_3 && resource_version == 0) { + priv->timer = devm_kzalloc(dev, sizeof(struct mlxbf_i2c_resource), GFP_KERNEL); + if (!priv->timer) + return -ENOMEM; + + priv->mst = devm_kzalloc(dev, sizeof(struct mlxbf_i2c_resource), GFP_KERNEL); + if (!priv->mst) + return -ENOMEM; + + priv->slv = devm_kzalloc(dev, sizeof(struct mlxbf_i2c_resource), GFP_KERNEL); + if (!priv->slv) + return -ENOMEM; + + ret = mlxbf_i2c_init_resource(pdev, &priv->smbus, + MLXBF_I2C_SMBUS_RES); + if (ret < 0) + return dev_err_probe(dev, ret, "Cannot fetch smbus resource info"); + + priv->timer->io = priv->smbus->io; + priv->mst->io = priv->smbus->io + MLXBF_I2C_MST_ADDR_OFFSET; + priv->slv->io = priv->smbus->io + MLXBF_I2C_SLV_ADDR_OFFSET; + } else { + ret = mlxbf_i2c_init_resource(pdev, &priv->timer, + MLXBF_I2C_SMBUS_TIMER_RES); + if (ret < 0) + return dev_err_probe(dev, ret, "Cannot fetch timer resource info"); + + ret = mlxbf_i2c_init_resource(pdev, &priv->mst, + MLXBF_I2C_SMBUS_MST_RES); + if (ret < 0) + return dev_err_probe(dev, ret, "Cannot fetch master resource info"); + + ret = mlxbf_i2c_init_resource(pdev, &priv->slv, + MLXBF_I2C_SMBUS_SLV_RES); + if (ret < 0) + return dev_err_probe(dev, ret, "Cannot fetch slave resource info"); + } + + ret = mlxbf_i2c_init_resource(pdev, &priv->mst_cause, + MLXBF_I2C_MST_CAUSE_RES); + if (ret < 0) + return dev_err_probe(dev, ret, "Cannot fetch cause master resource info"); + + ret = mlxbf_i2c_init_resource(pdev, &priv->slv_cause, + MLXBF_I2C_SLV_CAUSE_RES); + if (ret < 0) + return dev_err_probe(dev, ret, "Cannot fetch cause slave resource info"); + + adap = &priv->adap; + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_HWMON; + adap->algo = &mlxbf_i2c_algo; + adap->quirks = &mlxbf_i2c_quirks; + adap->dev.parent = dev; + adap->dev.of_node = dev->of_node; + adap->nr = priv->bus; + + snprintf(adap->name, sizeof(adap->name), "i2c%d", adap->nr); + i2c_set_adapdata(adap, priv); + + /* Read Core PLL frequency. */ + ret = mlxbf_i2c_calculate_corepll_freq(pdev, priv); + if (ret < 0) { + dev_err(dev, "cannot get core clock frequency\n"); + /* Set to default value. */ + priv->frequency = MLXBF_I2C_COREPLL_FREQ; + } + + /* + * Initialize master. + * Note that a physical bus might be shared among Linux and firmware + * (e.g., ATF). Thus, the bus should be initialized and ready and + * bus initialization would be unnecessary. This requires additional + * knowledge about physical busses. But, since an extra initialization + * does not really hurt, then keep the code as is. + */ + ret = mlxbf_i2c_init_master(pdev, priv); + if (ret < 0) + return dev_err_probe(dev, ret, "failed to initialize smbus master %d", + priv->bus); + + mlxbf_i2c_init_timings(pdev, priv); + + mlxbf_i2c_init_slave(pdev, priv); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + ret = devm_request_irq(dev, irq, mlxbf_i2c_irq, + IRQF_SHARED | IRQF_PROBE_SHARED, + dev_name(dev), priv); + if (ret < 0) + return dev_err_probe(dev, ret, "Cannot get irq %d\n", irq); + + priv->irq = irq; + + platform_set_drvdata(pdev, priv); + + ret = i2c_add_numbered_adapter(adap); + if (ret < 0) + return ret; + + mutex_lock(&mlxbf_i2c_bus_lock); + mlxbf_i2c_bus_count++; + mutex_unlock(&mlxbf_i2c_bus_lock); + + return 0; +} + +static void mlxbf_i2c_remove(struct platform_device *pdev) +{ + struct mlxbf_i2c_priv *priv = platform_get_drvdata(pdev); + struct device *dev = &pdev->dev; + struct resource *params; + + if (priv->chip->type < MLXBF_I2C_CHIP_TYPE_3 && priv->resource_version == 0) { + params = priv->smbus->params; + devm_release_mem_region(dev, params->start, resource_size(params)); + } else { + params = priv->timer->params; + devm_release_mem_region(dev, params->start, resource_size(params)); + + params = priv->mst->params; + devm_release_mem_region(dev, params->start, resource_size(params)); + + params = priv->slv->params; + devm_release_mem_region(dev, params->start, resource_size(params)); + } + + params = priv->mst_cause->params; + devm_release_mem_region(dev, params->start, resource_size(params)); + + params = priv->slv_cause->params; + devm_release_mem_region(dev, params->start, resource_size(params)); + + /* + * Release shared resources. This should be done when releasing + * the I2C controller. + */ + mutex_lock(&mlxbf_i2c_bus_lock); + if (--mlxbf_i2c_bus_count == 0) { + mlxbf_i2c_release_coalesce(pdev, priv); + mlxbf_i2c_release_corepll(pdev, priv); + mlxbf_i2c_release_gpio(pdev, priv); + } + mutex_unlock(&mlxbf_i2c_bus_lock); + + devm_free_irq(dev, priv->irq, priv); + + i2c_del_adapter(&priv->adap); +} + +static struct platform_driver mlxbf_i2c_driver = { + .probe = mlxbf_i2c_probe, + .remove_new = mlxbf_i2c_remove, + .driver = { + .name = "i2c-mlxbf", + .acpi_match_table = ACPI_PTR(mlxbf_i2c_acpi_ids), + }, +}; + +static int __init mlxbf_i2c_init(void) +{ + mutex_init(&mlxbf_i2c_coalesce_lock); + mutex_init(&mlxbf_i2c_corepll_lock); + mutex_init(&mlxbf_i2c_gpio_lock); + + mutex_init(&mlxbf_i2c_bus_lock); + + return platform_driver_register(&mlxbf_i2c_driver); +} +module_init(mlxbf_i2c_init); + +static void __exit mlxbf_i2c_exit(void) +{ + platform_driver_unregister(&mlxbf_i2c_driver); + + mutex_destroy(&mlxbf_i2c_bus_lock); + + mutex_destroy(&mlxbf_i2c_gpio_lock); + mutex_destroy(&mlxbf_i2c_corepll_lock); + mutex_destroy(&mlxbf_i2c_coalesce_lock); +} +module_exit(mlxbf_i2c_exit); + +MODULE_DESCRIPTION("Mellanox BlueField I2C bus driver"); +MODULE_AUTHOR("Khalil Blaiech <kblaiech@nvidia.com>"); +MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-mlxcpld.c b/drivers/i2c/busses/i2c-mlxcpld.c new file mode 100644 index 000000000..6fec64ea6 --- /dev/null +++ b/drivers/i2c/busses/i2c-mlxcpld.c @@ -0,0 +1,605 @@ +// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 +/* + * Mellanox i2c driver + * + * Copyright (C) 2016-2020 Mellanox Technologies + */ + +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_data/mlxreg.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +/* General defines */ +#define MLXPLAT_CPLD_LPC_I2C_BASE_ADDR 0x2000 +#define MLXCPLD_I2C_DEVICE_NAME "i2c_mlxcpld" +#define MLXCPLD_I2C_VALID_FLAG (I2C_M_RECV_LEN | I2C_M_RD) +#define MLXCPLD_I2C_BUS_NUM 1 +#define MLXCPLD_I2C_DATA_REG_SZ 36 +#define MLXCPLD_I2C_DATA_SZ_BIT BIT(5) +#define MLXCPLD_I2C_DATA_EXT2_SZ_BIT BIT(6) +#define MLXCPLD_I2C_DATA_SZ_MASK GENMASK(6, 5) +#define MLXCPLD_I2C_SMBUS_BLK_BIT BIT(7) +#define MLXCPLD_I2C_MAX_ADDR_LEN 4 +#define MLXCPLD_I2C_RETR_NUM 2 +#define MLXCPLD_I2C_XFER_TO 500000 /* usec */ +#define MLXCPLD_I2C_POLL_TIME 200 /* usec */ + +/* LPC I2C registers */ +#define MLXCPLD_LPCI2C_CPBLTY_REG 0x0 +#define MLXCPLD_LPCI2C_CTRL_REG 0x1 +#define MLXCPLD_LPCI2C_HALF_CYC_REG 0x4 +#define MLXCPLD_LPCI2C_I2C_HOLD_REG 0x5 +#define MLXCPLD_LPCI2C_CMD_REG 0x6 +#define MLXCPLD_LPCI2C_NUM_DAT_REG 0x7 +#define MLXCPLD_LPCI2C_NUM_ADDR_REG 0x8 +#define MLXCPLD_LPCI2C_STATUS_REG 0x9 +#define MLXCPLD_LPCI2C_DATA_REG 0xa + +/* LPC I2C masks and parameters */ +#define MLXCPLD_LPCI2C_RST_SEL_MASK 0x1 +#define MLXCPLD_LPCI2C_TRANS_END 0x1 +#define MLXCPLD_LPCI2C_STATUS_NACK 0x10 +#define MLXCPLD_LPCI2C_NO_IND 0 +#define MLXCPLD_LPCI2C_ACK_IND 1 +#define MLXCPLD_LPCI2C_NACK_IND 2 + +#define MLXCPLD_I2C_FREQ_1000KHZ_SET 0x04 +#define MLXCPLD_I2C_FREQ_400KHZ_SET 0x0e +#define MLXCPLD_I2C_FREQ_100KHZ_SET 0x42 + +enum mlxcpld_i2c_frequency { + MLXCPLD_I2C_FREQ_1000KHZ = 1, + MLXCPLD_I2C_FREQ_400KHZ = 2, + MLXCPLD_I2C_FREQ_100KHZ = 3, +}; + +struct mlxcpld_i2c_curr_xfer { + u8 cmd; + u8 addr_width; + u8 data_len; + u8 msg_num; + struct i2c_msg *msg; +}; + +struct mlxcpld_i2c_priv { + struct i2c_adapter adap; + u32 base_addr; + struct mutex lock; + struct mlxcpld_i2c_curr_xfer xfer; + struct device *dev; + bool smbus_block; + int polling_time; +}; + +static void mlxcpld_i2c_lpc_write_buf(u8 *data, u8 len, u32 addr) +{ + int i; + + for (i = 0; i < len - len % 4; i += 4) + outl(*(u32 *)(data + i), addr + i); + for (; i < len; ++i) + outb(*(data + i), addr + i); +} + +static void mlxcpld_i2c_lpc_read_buf(u8 *data, u8 len, u32 addr) +{ + int i; + + for (i = 0; i < len - len % 4; i += 4) + *(u32 *)(data + i) = inl(addr + i); + for (; i < len; ++i) + *(data + i) = inb(addr + i); +} + +static void mlxcpld_i2c_read_comm(struct mlxcpld_i2c_priv *priv, u8 offs, + u8 *data, u8 datalen) +{ + u32 addr = priv->base_addr + offs; + + switch (datalen) { + case 1: + *(data) = inb(addr); + break; + case 2: + *((u16 *)data) = inw(addr); + break; + case 3: + *((u16 *)data) = inw(addr); + *(data + 2) = inb(addr + 2); + break; + case 4: + *((u32 *)data) = inl(addr); + break; + default: + mlxcpld_i2c_lpc_read_buf(data, datalen, addr); + break; + } +} + +static void mlxcpld_i2c_write_comm(struct mlxcpld_i2c_priv *priv, u8 offs, + u8 *data, u8 datalen) +{ + u32 addr = priv->base_addr + offs; + + switch (datalen) { + case 1: + outb(*(data), addr); + break; + case 2: + outw(*((u16 *)data), addr); + break; + case 3: + outw(*((u16 *)data), addr); + outb(*(data + 2), addr + 2); + break; + case 4: + outl(*((u32 *)data), addr); + break; + default: + mlxcpld_i2c_lpc_write_buf(data, datalen, addr); + break; + } +} + +/* + * Check validity of received i2c messages parameters. + * Returns 0 if OK, other - in case of invalid parameters. + */ +static int mlxcpld_i2c_check_msg_params(struct mlxcpld_i2c_priv *priv, + struct i2c_msg *msgs, int num) +{ + int i; + + if (!num) { + dev_err(priv->dev, "Incorrect 0 num of messages\n"); + return -EINVAL; + } + + if (unlikely(msgs[0].addr > 0x7f)) { + dev_err(priv->dev, "Invalid address 0x%03x\n", + msgs[0].addr); + return -EINVAL; + } + + for (i = 0; i < num; ++i) { + if (unlikely(!msgs[i].buf)) { + dev_err(priv->dev, "Invalid buf in msg[%d]\n", + i); + return -EINVAL; + } + if (unlikely(msgs[0].addr != msgs[i].addr)) { + dev_err(priv->dev, "Invalid addr in msg[%d]\n", + i); + return -EINVAL; + } + } + + return 0; +} + +/* + * Check if transfer is completed and status of operation. + * Returns 0 - transfer completed (both ACK or NACK), + * negative - transfer isn't finished. + */ +static int mlxcpld_i2c_check_status(struct mlxcpld_i2c_priv *priv, int *status) +{ + u8 val; + + mlxcpld_i2c_read_comm(priv, MLXCPLD_LPCI2C_STATUS_REG, &val, 1); + + if (val & MLXCPLD_LPCI2C_TRANS_END) { + if (val & MLXCPLD_LPCI2C_STATUS_NACK) + /* + * The slave is unable to accept the data. No such + * slave, command not understood, or unable to accept + * any more data. + */ + *status = MLXCPLD_LPCI2C_NACK_IND; + else + *status = MLXCPLD_LPCI2C_ACK_IND; + return 0; + } + *status = MLXCPLD_LPCI2C_NO_IND; + + return -EIO; +} + +static void mlxcpld_i2c_set_transf_data(struct mlxcpld_i2c_priv *priv, + struct i2c_msg *msgs, int num, + u8 comm_len) +{ + priv->xfer.msg = msgs; + priv->xfer.msg_num = num; + + /* + * All upper layers currently are never use transfer with more than + * 2 messages. Actually, it's also not so relevant in Mellanox systems + * because of HW limitation. Max size of transfer is not more than 32 + * or 68 bytes in the current x86 LPCI2C bridge. + */ + priv->xfer.cmd = msgs[num - 1].flags & I2C_M_RD; + + if (priv->xfer.cmd == I2C_M_RD && comm_len != msgs[0].len) { + priv->xfer.addr_width = msgs[0].len; + priv->xfer.data_len = comm_len - priv->xfer.addr_width; + } else { + priv->xfer.addr_width = 0; + priv->xfer.data_len = comm_len; + } +} + +/* Reset CPLD LPCI2C block */ +static void mlxcpld_i2c_reset(struct mlxcpld_i2c_priv *priv) +{ + u8 val; + + mutex_lock(&priv->lock); + + mlxcpld_i2c_read_comm(priv, MLXCPLD_LPCI2C_CTRL_REG, &val, 1); + val &= ~MLXCPLD_LPCI2C_RST_SEL_MASK; + mlxcpld_i2c_write_comm(priv, MLXCPLD_LPCI2C_CTRL_REG, &val, 1); + + mutex_unlock(&priv->lock); +} + +/* Make sure the CPLD is ready to start transmitting. */ +static int mlxcpld_i2c_check_busy(struct mlxcpld_i2c_priv *priv) +{ + u8 val; + + mlxcpld_i2c_read_comm(priv, MLXCPLD_LPCI2C_STATUS_REG, &val, 1); + + if (val & MLXCPLD_LPCI2C_TRANS_END) + return 0; + + return -EIO; +} + +static int mlxcpld_i2c_wait_for_free(struct mlxcpld_i2c_priv *priv) +{ + int timeout = 0; + + do { + if (!mlxcpld_i2c_check_busy(priv)) + break; + usleep_range(priv->polling_time / 2, priv->polling_time); + timeout += priv->polling_time; + } while (timeout <= MLXCPLD_I2C_XFER_TO); + + if (timeout > MLXCPLD_I2C_XFER_TO) + return -ETIMEDOUT; + + return 0; +} + +/* + * Wait for master transfer to complete. + * It puts current process to sleep until we get interrupt or timeout expires. + * Returns the number of transferred or read bytes or error (<0). + */ +static int mlxcpld_i2c_wait_for_tc(struct mlxcpld_i2c_priv *priv) +{ + int status, i, timeout = 0; + u8 datalen, val; + + do { + usleep_range(priv->polling_time / 2, priv->polling_time); + if (!mlxcpld_i2c_check_status(priv, &status)) + break; + timeout += priv->polling_time; + } while (status == 0 && timeout < MLXCPLD_I2C_XFER_TO); + + switch (status) { + case MLXCPLD_LPCI2C_NO_IND: + return -ETIMEDOUT; + + case MLXCPLD_LPCI2C_ACK_IND: + if (priv->xfer.cmd != I2C_M_RD) + return (priv->xfer.addr_width + priv->xfer.data_len); + + if (priv->xfer.msg_num == 1) + i = 0; + else + i = 1; + + if (!priv->xfer.msg[i].buf) + return -EINVAL; + + /* + * Actual read data len will be always the same as + * requested len. 0xff (line pull-up) will be returned + * if slave has no data to return. Thus don't read + * MLXCPLD_LPCI2C_NUM_DAT_REG reg from CPLD. Only in case of + * SMBus block read transaction data len can be different, + * check this case. + */ + mlxcpld_i2c_read_comm(priv, MLXCPLD_LPCI2C_NUM_ADDR_REG, &val, + 1); + if (priv->smbus_block && (val & MLXCPLD_I2C_SMBUS_BLK_BIT)) { + mlxcpld_i2c_read_comm(priv, MLXCPLD_LPCI2C_NUM_DAT_REG, + &datalen, 1); + if (unlikely(datalen > I2C_SMBUS_BLOCK_MAX)) { + dev_err(priv->dev, "Incorrect smbus block read message len\n"); + return -EPROTO; + } + } else { + datalen = priv->xfer.data_len; + } + + mlxcpld_i2c_read_comm(priv, MLXCPLD_LPCI2C_DATA_REG, + priv->xfer.msg[i].buf, datalen); + + return datalen; + + case MLXCPLD_LPCI2C_NACK_IND: + return -ENXIO; + + default: + return -EINVAL; + } +} + +static void mlxcpld_i2c_xfer_msg(struct mlxcpld_i2c_priv *priv) +{ + int i, len = 0; + u8 cmd, val; + + mlxcpld_i2c_write_comm(priv, MLXCPLD_LPCI2C_NUM_DAT_REG, + &priv->xfer.data_len, 1); + + val = priv->xfer.addr_width; + /* Notify HW about SMBus block read transaction */ + if (priv->smbus_block && priv->xfer.msg_num >= 2 && + priv->xfer.msg[1].len == 1 && + (priv->xfer.msg[1].flags & I2C_M_RECV_LEN) && + (priv->xfer.msg[1].flags & I2C_M_RD)) + val |= MLXCPLD_I2C_SMBUS_BLK_BIT; + + mlxcpld_i2c_write_comm(priv, MLXCPLD_LPCI2C_NUM_ADDR_REG, &val, 1); + + for (i = 0; i < priv->xfer.msg_num; i++) { + if ((priv->xfer.msg[i].flags & I2C_M_RD) != I2C_M_RD) { + /* Don't write to CPLD buffer in read transaction */ + mlxcpld_i2c_write_comm(priv, MLXCPLD_LPCI2C_DATA_REG + + len, priv->xfer.msg[i].buf, + priv->xfer.msg[i].len); + len += priv->xfer.msg[i].len; + } + } + + /* + * Set target slave address with command for master transfer. + * It should be latest executed function before CPLD transaction. + */ + cmd = (priv->xfer.msg[0].addr << 1) | priv->xfer.cmd; + mlxcpld_i2c_write_comm(priv, MLXCPLD_LPCI2C_CMD_REG, &cmd, 1); +} + +/* + * Generic lpc-i2c transfer. + * Returns the number of processed messages or error (<0). + */ +static int mlxcpld_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct mlxcpld_i2c_priv *priv = i2c_get_adapdata(adap); + u8 comm_len = 0; + int i, err; + + err = mlxcpld_i2c_check_msg_params(priv, msgs, num); + if (err) { + dev_err(priv->dev, "Incorrect message\n"); + return err; + } + + for (i = 0; i < num; ++i) + comm_len += msgs[i].len; + + /* Check bus state */ + if (mlxcpld_i2c_wait_for_free(priv)) { + dev_err(priv->dev, "LPCI2C bridge is busy\n"); + + /* + * Usually it means something serious has happened. + * We can not have unfinished previous transfer + * so it doesn't make any sense to try to stop it. + * Probably we were not able to recover from the + * previous error. + * The only reasonable thing - is soft reset. + */ + mlxcpld_i2c_reset(priv); + if (mlxcpld_i2c_check_busy(priv)) { + dev_err(priv->dev, "LPCI2C bridge is busy after reset\n"); + return -EIO; + } + } + + mlxcpld_i2c_set_transf_data(priv, msgs, num, comm_len); + + mutex_lock(&priv->lock); + + /* Do real transfer. Can't fail */ + mlxcpld_i2c_xfer_msg(priv); + + /* Wait for transaction complete */ + err = mlxcpld_i2c_wait_for_tc(priv); + + mutex_unlock(&priv->lock); + + return err < 0 ? err : num; +} + +static u32 mlxcpld_i2c_func(struct i2c_adapter *adap) +{ + struct mlxcpld_i2c_priv *priv = i2c_get_adapdata(adap); + + if (priv->smbus_block) + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | + I2C_FUNC_SMBUS_I2C_BLOCK | I2C_FUNC_SMBUS_BLOCK_DATA; + else + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | + I2C_FUNC_SMBUS_I2C_BLOCK; +} + +static const struct i2c_algorithm mlxcpld_i2c_algo = { + .master_xfer = mlxcpld_i2c_xfer, + .functionality = mlxcpld_i2c_func +}; + +static const struct i2c_adapter_quirks mlxcpld_i2c_quirks = { + .flags = I2C_AQ_COMB_WRITE_THEN_READ, + .max_read_len = MLXCPLD_I2C_DATA_REG_SZ - MLXCPLD_I2C_MAX_ADDR_LEN, + .max_write_len = MLXCPLD_I2C_DATA_REG_SZ, + .max_comb_1st_msg_len = 4, +}; + +static const struct i2c_adapter_quirks mlxcpld_i2c_quirks_ext = { + .flags = I2C_AQ_COMB_WRITE_THEN_READ, + .max_read_len = MLXCPLD_I2C_DATA_REG_SZ * 2 - MLXCPLD_I2C_MAX_ADDR_LEN, + .max_write_len = MLXCPLD_I2C_DATA_REG_SZ * 2, + .max_comb_1st_msg_len = 4, +}; + +static const struct i2c_adapter_quirks mlxcpld_i2c_quirks_ext2 = { + .flags = I2C_AQ_COMB_WRITE_THEN_READ, + .max_read_len = (MLXCPLD_I2C_DATA_REG_SZ - 4) * 4, + .max_write_len = (MLXCPLD_I2C_DATA_REG_SZ - 4) * 4 + MLXCPLD_I2C_MAX_ADDR_LEN, + .max_comb_1st_msg_len = 4, +}; + +static struct i2c_adapter mlxcpld_i2c_adapter = { + .owner = THIS_MODULE, + .name = "i2c-mlxcpld", + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = &mlxcpld_i2c_algo, + .quirks = &mlxcpld_i2c_quirks, + .retries = MLXCPLD_I2C_RETR_NUM, + .nr = MLXCPLD_I2C_BUS_NUM, +}; + +static int +mlxcpld_i2c_set_frequency(struct mlxcpld_i2c_priv *priv, + struct mlxreg_core_hotplug_platform_data *pdata) +{ + struct mlxreg_core_item *item = pdata->items; + struct mlxreg_core_data *data; + u32 regval; + u8 freq; + int err; + + if (!item) + return 0; + + /* Read frequency setting. */ + data = item->data; + err = regmap_read(pdata->regmap, data->reg, ®val); + if (err) + return err; + + /* Set frequency only if it is not 100KHz, which is default. */ + switch ((regval & data->mask) >> data->bit) { + case MLXCPLD_I2C_FREQ_1000KHZ: + freq = MLXCPLD_I2C_FREQ_1000KHZ_SET; + priv->polling_time /= 4; + break; + case MLXCPLD_I2C_FREQ_400KHZ: + freq = MLXCPLD_I2C_FREQ_400KHZ_SET; + priv->polling_time /= 4; + break; + default: + return 0; + } + + mlxcpld_i2c_write_comm(priv, MLXCPLD_LPCI2C_HALF_CYC_REG, &freq, 1); + + return 0; +} + +static int mlxcpld_i2c_probe(struct platform_device *pdev) +{ + struct mlxreg_core_hotplug_platform_data *pdata; + struct mlxcpld_i2c_priv *priv; + int err; + u8 val; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + mutex_init(&priv->lock); + platform_set_drvdata(pdev, priv); + + priv->dev = &pdev->dev; + priv->base_addr = MLXPLAT_CPLD_LPC_I2C_BASE_ADDR; + priv->polling_time = MLXCPLD_I2C_POLL_TIME; + + /* Set I2C bus frequency if platform data provides this info. */ + pdata = dev_get_platdata(&pdev->dev); + if (pdata) { + err = mlxcpld_i2c_set_frequency(priv, pdata); + if (err) + goto mlxcpld_i2_probe_failed; + } + + /* Register with i2c layer */ + mlxcpld_i2c_adapter.timeout = usecs_to_jiffies(MLXCPLD_I2C_XFER_TO); + /* Read capability register */ + mlxcpld_i2c_read_comm(priv, MLXCPLD_LPCI2C_CPBLTY_REG, &val, 1); + /* Check support for extended transaction length */ + if ((val & MLXCPLD_I2C_DATA_SZ_MASK) == MLXCPLD_I2C_DATA_SZ_BIT) + mlxcpld_i2c_adapter.quirks = &mlxcpld_i2c_quirks_ext; + else if ((val & MLXCPLD_I2C_DATA_SZ_MASK) == MLXCPLD_I2C_DATA_EXT2_SZ_BIT) + mlxcpld_i2c_adapter.quirks = &mlxcpld_i2c_quirks_ext2; + /* Check support for smbus block transaction */ + if (val & MLXCPLD_I2C_SMBUS_BLK_BIT) + priv->smbus_block = true; + if (pdev->id >= -1) + mlxcpld_i2c_adapter.nr = pdev->id; + priv->adap = mlxcpld_i2c_adapter; + priv->adap.dev.parent = &pdev->dev; + i2c_set_adapdata(&priv->adap, priv); + + err = i2c_add_numbered_adapter(&priv->adap); + if (err) + goto mlxcpld_i2_probe_failed; + + /* Notify caller when adapter is added. */ + if (pdata && pdata->completion_notify) + pdata->completion_notify(pdata->handle, mlxcpld_i2c_adapter.nr); + + return 0; + +mlxcpld_i2_probe_failed: + mutex_destroy(&priv->lock); + return err; +} + +static void mlxcpld_i2c_remove(struct platform_device *pdev) +{ + struct mlxcpld_i2c_priv *priv = platform_get_drvdata(pdev); + + i2c_del_adapter(&priv->adap); + mutex_destroy(&priv->lock); +} + +static struct platform_driver mlxcpld_i2c_driver = { + .probe = mlxcpld_i2c_probe, + .remove_new = mlxcpld_i2c_remove, + .driver = { + .name = MLXCPLD_I2C_DEVICE_NAME, + }, +}; + +module_platform_driver(mlxcpld_i2c_driver); + +MODULE_AUTHOR("Michael Shych <michaels@mellanox.com>"); +MODULE_DESCRIPTION("Mellanox I2C-CPLD controller driver"); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_ALIAS("platform:i2c-mlxcpld"); diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c new file mode 100644 index 000000000..e4e4995ab --- /dev/null +++ b/drivers/i2c/busses/i2c-mpc.c @@ -0,0 +1,974 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * This is a combined i2c adapter and algorithm driver for the + * MPC107/Tsi107 PowerPC northbridge and processors that include + * the same I2C unit (8240, 8245, 85xx). + * + * Copyright (C) 2003-2004 Humboldt Solutions Ltd, adrian@humboldt.co.uk + * Copyright (C) 2021 Allied Telesis Labs + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/sched/signal.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> +#include <linux/property.h> +#include <linux/slab.h> + +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/fsl_devices.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/delay.h> + +#include <asm/mpc52xx.h> +#include <asm/mpc85xx.h> +#include <sysdev/fsl_soc.h> + +#define DRV_NAME "mpc-i2c" + +#define MPC_I2C_CLOCK_LEGACY 0 +#define MPC_I2C_CLOCK_PRESERVE (~0U) + +#define MPC_I2C_FDR 0x04 +#define MPC_I2C_CR 0x08 +#define MPC_I2C_SR 0x0c +#define MPC_I2C_DR 0x10 +#define MPC_I2C_DFSRR 0x14 + +#define CCR_MEN 0x80 +#define CCR_MIEN 0x40 +#define CCR_MSTA 0x20 +#define CCR_MTX 0x10 +#define CCR_TXAK 0x08 +#define CCR_RSTA 0x04 +#define CCR_RSVD 0x02 + +#define CSR_MCF 0x80 +#define CSR_MAAS 0x40 +#define CSR_MBB 0x20 +#define CSR_MAL 0x10 +#define CSR_SRW 0x04 +#define CSR_MIF 0x02 +#define CSR_RXAK 0x01 + +enum mpc_i2c_action { + MPC_I2C_ACTION_START = 1, + MPC_I2C_ACTION_RESTART, + MPC_I2C_ACTION_READ_BEGIN, + MPC_I2C_ACTION_READ_BYTE, + MPC_I2C_ACTION_WRITE, + MPC_I2C_ACTION_STOP, + + __MPC_I2C_ACTION_CNT +}; + +static const char * const action_str[] = { + "invalid", + "start", + "restart", + "read begin", + "read", + "write", + "stop", +}; + +static_assert(ARRAY_SIZE(action_str) == __MPC_I2C_ACTION_CNT); + +struct mpc_i2c { + struct device *dev; + void __iomem *base; + u32 interrupt; + wait_queue_head_t waitq; + spinlock_t lock; + struct i2c_adapter adap; + int irq; + u32 real_clk; + u8 fdr, dfsrr; + struct clk *clk_per; + u32 cntl_bits; + enum mpc_i2c_action action; + struct i2c_msg *msgs; + int num_msgs; + int curr_msg; + u32 byte_posn; + u32 block; + int rc; + int expect_rxack; + bool has_errata_A004447; +}; + +struct mpc_i2c_divider { + u16 divider; + u16 fdr; /* including dfsrr */ +}; + +struct mpc_i2c_data { + void (*setup)(struct device_node *node, struct mpc_i2c *i2c, u32 clock); +}; + +static inline void writeccr(struct mpc_i2c *i2c, u32 x) +{ + writeb(x, i2c->base + MPC_I2C_CR); +} + +/* Sometimes 9th clock pulse isn't generated, and slave doesn't release + * the bus, because it wants to send ACK. + * Following sequence of enabling/disabling and sending start/stop generates + * the 9 pulses, each with a START then ending with STOP, so it's all OK. + */ +static void mpc_i2c_fixup(struct mpc_i2c *i2c) +{ + int k; + unsigned long flags; + + for (k = 9; k; k--) { + writeccr(i2c, 0); + writeb(0, i2c->base + MPC_I2C_SR); /* clear any status bits */ + writeccr(i2c, CCR_MEN | CCR_MSTA); /* START */ + readb(i2c->base + MPC_I2C_DR); /* init xfer */ + udelay(15); /* let it hit the bus */ + local_irq_save(flags); /* should not be delayed further */ + writeccr(i2c, CCR_MEN | CCR_MSTA | CCR_RSTA); /* delay SDA */ + readb(i2c->base + MPC_I2C_DR); + if (k != 1) + udelay(5); + local_irq_restore(flags); + } + writeccr(i2c, CCR_MEN); /* Initiate STOP */ + readb(i2c->base + MPC_I2C_DR); + udelay(15); /* Let STOP propagate */ + writeccr(i2c, 0); +} + +static int i2c_mpc_wait_sr(struct mpc_i2c *i2c, int mask) +{ + void __iomem *addr = i2c->base + MPC_I2C_SR; + u8 val; + + return readb_poll_timeout(addr, val, val & mask, 0, 100); +} + +/* + * Workaround for Erratum A004447. From the P2040CE Rev Q + * + * 1. Set up the frequency divider and sampling rate. + * 2. I2CCR - a0h + * 3. Poll for I2CSR[MBB] to get set. + * 4. If I2CSR[MAL] is set (an indication that SDA is stuck low), then go to + * step 5. If MAL is not set, then go to step 13. + * 5. I2CCR - 00h + * 6. I2CCR - 22h + * 7. I2CCR - a2h + * 8. Poll for I2CSR[MBB] to get set. + * 9. Issue read to I2CDR. + * 10. Poll for I2CSR[MIF] to be set. + * 11. I2CCR - 82h + * 12. Workaround complete. Skip the next steps. + * 13. Issue read to I2CDR. + * 14. Poll for I2CSR[MIF] to be set. + * 15. I2CCR - 80h + */ +static void mpc_i2c_fixup_A004447(struct mpc_i2c *i2c) +{ + int ret; + u32 val; + + writeccr(i2c, CCR_MEN | CCR_MSTA); + ret = i2c_mpc_wait_sr(i2c, CSR_MBB); + if (ret) { + dev_err(i2c->dev, "timeout waiting for CSR_MBB\n"); + return; + } + + val = readb(i2c->base + MPC_I2C_SR); + + if (val & CSR_MAL) { + writeccr(i2c, 0x00); + writeccr(i2c, CCR_MSTA | CCR_RSVD); + writeccr(i2c, CCR_MEN | CCR_MSTA | CCR_RSVD); + ret = i2c_mpc_wait_sr(i2c, CSR_MBB); + if (ret) { + dev_err(i2c->dev, "timeout waiting for CSR_MBB\n"); + return; + } + val = readb(i2c->base + MPC_I2C_DR); + ret = i2c_mpc_wait_sr(i2c, CSR_MIF); + if (ret) { + dev_err(i2c->dev, "timeout waiting for CSR_MIF\n"); + return; + } + writeccr(i2c, CCR_MEN | CCR_RSVD); + } else { + val = readb(i2c->base + MPC_I2C_DR); + ret = i2c_mpc_wait_sr(i2c, CSR_MIF); + if (ret) { + dev_err(i2c->dev, "timeout waiting for CSR_MIF\n"); + return; + } + writeccr(i2c, CCR_MEN); + } +} + +#if defined(CONFIG_PPC_MPC52xx) || defined(CONFIG_PPC_MPC512x) +static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] = { + {20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23}, + {28, 0x24}, {30, 0x01}, {32, 0x25}, {34, 0x02}, + {36, 0x26}, {40, 0x27}, {44, 0x04}, {48, 0x28}, + {52, 0x63}, {56, 0x29}, {60, 0x41}, {64, 0x2a}, + {68, 0x07}, {72, 0x2b}, {80, 0x2c}, {88, 0x09}, + {96, 0x2d}, {104, 0x0a}, {112, 0x2e}, {120, 0x81}, + {128, 0x2f}, {136, 0x47}, {144, 0x0c}, {160, 0x30}, + {176, 0x49}, {192, 0x31}, {208, 0x4a}, {224, 0x32}, + {240, 0x0f}, {256, 0x33}, {272, 0x87}, {288, 0x10}, + {320, 0x34}, {352, 0x89}, {384, 0x35}, {416, 0x8a}, + {448, 0x36}, {480, 0x13}, {512, 0x37}, {576, 0x14}, + {640, 0x38}, {768, 0x39}, {896, 0x3a}, {960, 0x17}, + {1024, 0x3b}, {1152, 0x18}, {1280, 0x3c}, {1536, 0x3d}, + {1792, 0x3e}, {1920, 0x1b}, {2048, 0x3f}, {2304, 0x1c}, + {2560, 0x1d}, {3072, 0x1e}, {3584, 0x7e}, {3840, 0x1f}, + {4096, 0x7f}, {4608, 0x5c}, {5120, 0x5d}, {6144, 0x5e}, + {7168, 0xbe}, {7680, 0x5f}, {8192, 0xbf}, {9216, 0x9c}, + {10240, 0x9d}, {12288, 0x9e}, {15360, 0x9f} +}; + +static int mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock, + u32 *real_clk) +{ + struct fwnode_handle *fwnode = of_fwnode_handle(node); + const struct mpc_i2c_divider *div = NULL; + unsigned int pvr = mfspr(SPRN_PVR); + u32 divider; + int i; + + if (clock == MPC_I2C_CLOCK_LEGACY) { + /* see below - default fdr = 0x3f -> div = 2048 */ + *real_clk = mpc5xxx_fwnode_get_bus_frequency(fwnode) / 2048; + return -EINVAL; + } + + /* Determine divider value */ + divider = mpc5xxx_fwnode_get_bus_frequency(fwnode) / clock; + + /* + * We want to choose an FDR/DFSR that generates an I2C bus speed that + * is equal to or lower than the requested speed. + */ + for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_52xx); i++) { + div = &mpc_i2c_dividers_52xx[i]; + /* Old MPC5200 rev A CPUs do not support the high bits */ + if (div->fdr & 0xc0 && pvr == 0x80822011) + continue; + if (div->divider >= divider) + break; + } + + *real_clk = mpc5xxx_fwnode_get_bus_frequency(fwnode) / div->divider; + return (int)div->fdr; +} + +static void mpc_i2c_setup_52xx(struct device_node *node, + struct mpc_i2c *i2c, + u32 clock) +{ + int ret, fdr; + + if (clock == MPC_I2C_CLOCK_PRESERVE) { + dev_dbg(i2c->dev, "using fdr %d\n", + readb(i2c->base + MPC_I2C_FDR)); + return; + } + + ret = mpc_i2c_get_fdr_52xx(node, clock, &i2c->real_clk); + fdr = (ret >= 0) ? ret : 0x3f; /* backward compatibility */ + + writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR); + + if (ret >= 0) + dev_info(i2c->dev, "clock %u Hz (fdr=%d)\n", i2c->real_clk, + fdr); +} +#else /* !(CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x) */ +static void mpc_i2c_setup_52xx(struct device_node *node, + struct mpc_i2c *i2c, + u32 clock) +{ +} +#endif /* CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x */ + +#ifdef CONFIG_PPC_MPC512x +static void mpc_i2c_setup_512x(struct device_node *node, + struct mpc_i2c *i2c, + u32 clock) +{ + struct device_node *node_ctrl; + void __iomem *ctrl; + u32 idx; + + /* Enable I2C interrupts for mpc5121 */ + node_ctrl = of_find_compatible_node(NULL, NULL, + "fsl,mpc5121-i2c-ctrl"); + if (node_ctrl) { + ctrl = of_iomap(node_ctrl, 0); + if (ctrl) { + u64 addr; + /* Interrupt enable bits for i2c-0/1/2: bit 24/26/28 */ + of_property_read_reg(node, 0, &addr, NULL); + idx = (addr & 0xff) / 0x20; + setbits32(ctrl, 1 << (24 + idx * 2)); + iounmap(ctrl); + } + of_node_put(node_ctrl); + } + + /* The clock setup for the 52xx works also fine for the 512x */ + mpc_i2c_setup_52xx(node, i2c, clock); +} +#else /* CONFIG_PPC_MPC512x */ +static void mpc_i2c_setup_512x(struct device_node *node, + struct mpc_i2c *i2c, + u32 clock) +{ +} +#endif /* CONFIG_PPC_MPC512x */ + +#ifdef CONFIG_FSL_SOC +static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] = { + {160, 0x0120}, {192, 0x0121}, {224, 0x0122}, {256, 0x0123}, + {288, 0x0100}, {320, 0x0101}, {352, 0x0601}, {384, 0x0102}, + {416, 0x0602}, {448, 0x0126}, {480, 0x0103}, {512, 0x0127}, + {544, 0x0b03}, {576, 0x0104}, {608, 0x1603}, {640, 0x0105}, + {672, 0x2003}, {704, 0x0b05}, {736, 0x2b03}, {768, 0x0106}, + {800, 0x3603}, {832, 0x0b06}, {896, 0x012a}, {960, 0x0107}, + {1024, 0x012b}, {1088, 0x1607}, {1152, 0x0108}, {1216, 0x2b07}, + {1280, 0x0109}, {1408, 0x1609}, {1536, 0x010a}, {1664, 0x160a}, + {1792, 0x012e}, {1920, 0x010b}, {2048, 0x012f}, {2176, 0x2b0b}, + {2304, 0x010c}, {2560, 0x010d}, {2816, 0x2b0d}, {3072, 0x010e}, + {3328, 0x2b0e}, {3584, 0x0132}, {3840, 0x010f}, {4096, 0x0133}, + {4608, 0x0110}, {5120, 0x0111}, {6144, 0x0112}, {7168, 0x0136}, + {7680, 0x0113}, {8192, 0x0137}, {9216, 0x0114}, {10240, 0x0115}, + {12288, 0x0116}, {14336, 0x013a}, {15360, 0x0117}, {16384, 0x013b}, + {18432, 0x0118}, {20480, 0x0119}, {24576, 0x011a}, {28672, 0x013e}, + {30720, 0x011b}, {32768, 0x013f}, {36864, 0x011c}, {40960, 0x011d}, + {49152, 0x011e}, {61440, 0x011f} +}; + +static u32 mpc_i2c_get_sec_cfg_8xxx(void) +{ + struct device_node *node; + u32 __iomem *reg; + u32 val = 0; + + node = of_find_node_by_name(NULL, "global-utilities"); + if (node) { + const u32 *prop = of_get_property(node, "reg", NULL); + if (prop) { + /* + * Map and check POR Device Status Register 2 + * (PORDEVSR2) at 0xE0014. Note than while MPC8533 + * and MPC8544 indicate SEC frequency ratio + * configuration as bit 26 in PORDEVSR2, other MPC8xxx + * parts may store it differently or may not have it + * at all. + */ + reg = ioremap(get_immrbase() + *prop + 0x14, 0x4); + if (!reg) + printk(KERN_ERR + "Error: couldn't map PORDEVSR2\n"); + else + val = in_be32(reg) & 0x00000020; /* sec-cfg */ + iounmap(reg); + } + } + of_node_put(node); + + return val; +} + +static u32 mpc_i2c_get_prescaler_8xxx(void) +{ + /* + * According to the AN2919 all MPC824x have prescaler 1, while MPC83xx + * may have prescaler 1, 2, or 3, depending on the power-on + * configuration. + */ + u32 prescaler = 1; + + /* mpc85xx */ + if (pvr_version_is(PVR_VER_E500V1) || pvr_version_is(PVR_VER_E500V2) + || pvr_version_is(PVR_VER_E500MC) + || pvr_version_is(PVR_VER_E5500) + || pvr_version_is(PVR_VER_E6500)) { + unsigned int svr = mfspr(SPRN_SVR); + + if ((SVR_SOC_VER(svr) == SVR_8540) + || (SVR_SOC_VER(svr) == SVR_8541) + || (SVR_SOC_VER(svr) == SVR_8560) + || (SVR_SOC_VER(svr) == SVR_8555) + || (SVR_SOC_VER(svr) == SVR_8610)) + /* the above 85xx SoCs have prescaler 1 */ + prescaler = 1; + else if ((SVR_SOC_VER(svr) == SVR_8533) + || (SVR_SOC_VER(svr) == SVR_8544)) + /* the above 85xx SoCs have prescaler 3 or 2 */ + prescaler = mpc_i2c_get_sec_cfg_8xxx() ? 3 : 2; + else + /* all the other 85xx have prescaler 2 */ + prescaler = 2; + } + + return prescaler; +} + +static int mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock, + u32 *real_clk) +{ + const struct mpc_i2c_divider *div = NULL; + u32 prescaler = mpc_i2c_get_prescaler_8xxx(); + u32 divider; + int i; + + if (clock == MPC_I2C_CLOCK_LEGACY) { + /* see below - default fdr = 0x1031 -> div = 16 * 3072 */ + *real_clk = fsl_get_sys_freq() / prescaler / (16 * 3072); + return -EINVAL; + } + + divider = fsl_get_sys_freq() / clock / prescaler; + + pr_debug("I2C: src_clock=%d clock=%d divider=%d\n", + fsl_get_sys_freq(), clock, divider); + + /* + * We want to choose an FDR/DFSR that generates an I2C bus speed that + * is equal to or lower than the requested speed. + */ + for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_8xxx); i++) { + div = &mpc_i2c_dividers_8xxx[i]; + if (div->divider >= divider) + break; + } + + *real_clk = fsl_get_sys_freq() / prescaler / div->divider; + return (int)div->fdr; +} + +static void mpc_i2c_setup_8xxx(struct device_node *node, + struct mpc_i2c *i2c, + u32 clock) +{ + int ret, fdr; + + if (clock == MPC_I2C_CLOCK_PRESERVE) { + dev_dbg(i2c->dev, "using dfsrr %d, fdr %d\n", + readb(i2c->base + MPC_I2C_DFSRR), + readb(i2c->base + MPC_I2C_FDR)); + return; + } + + ret = mpc_i2c_get_fdr_8xxx(node, clock, &i2c->real_clk); + fdr = (ret >= 0) ? ret : 0x1031; /* backward compatibility */ + + writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR); + writeb((fdr >> 8) & 0xff, i2c->base + MPC_I2C_DFSRR); + + if (ret >= 0) + dev_info(i2c->dev, "clock %d Hz (dfsrr=%d fdr=%d)\n", + i2c->real_clk, fdr >> 8, fdr & 0xff); +} + +#else /* !CONFIG_FSL_SOC */ +static void mpc_i2c_setup_8xxx(struct device_node *node, + struct mpc_i2c *i2c, + u32 clock) +{ +} +#endif /* CONFIG_FSL_SOC */ + +static void mpc_i2c_finish(struct mpc_i2c *i2c, int rc) +{ + i2c->rc = rc; + i2c->block = 0; + i2c->cntl_bits = CCR_MEN; + writeccr(i2c, i2c->cntl_bits); + wake_up(&i2c->waitq); +} + +static void mpc_i2c_do_action(struct mpc_i2c *i2c) +{ + struct i2c_msg *msg = NULL; + int dir = 0; + int recv_len = 0; + u8 byte; + + dev_dbg(i2c->dev, "action = %s\n", action_str[i2c->action]); + + i2c->cntl_bits &= ~(CCR_RSTA | CCR_MTX | CCR_TXAK); + + if (i2c->action != MPC_I2C_ACTION_STOP) { + msg = &i2c->msgs[i2c->curr_msg]; + if (msg->flags & I2C_M_RD) + dir = 1; + if (msg->flags & I2C_M_RECV_LEN) + recv_len = 1; + } + + switch (i2c->action) { + case MPC_I2C_ACTION_RESTART: + i2c->cntl_bits |= CCR_RSTA; + fallthrough; + + case MPC_I2C_ACTION_START: + i2c->cntl_bits |= CCR_MSTA | CCR_MTX; + writeccr(i2c, i2c->cntl_bits); + writeb((msg->addr << 1) | dir, i2c->base + MPC_I2C_DR); + i2c->expect_rxack = 1; + i2c->action = dir ? MPC_I2C_ACTION_READ_BEGIN : MPC_I2C_ACTION_WRITE; + break; + + case MPC_I2C_ACTION_READ_BEGIN: + if (msg->len) { + if (msg->len == 1 && !(msg->flags & I2C_M_RECV_LEN)) + i2c->cntl_bits |= CCR_TXAK; + + writeccr(i2c, i2c->cntl_bits); + /* Dummy read */ + readb(i2c->base + MPC_I2C_DR); + } + i2c->action = MPC_I2C_ACTION_READ_BYTE; + break; + + case MPC_I2C_ACTION_READ_BYTE: + if (i2c->byte_posn || !recv_len) { + /* Generate Tx ACK on next to last byte */ + if (i2c->byte_posn == msg->len - 2) + i2c->cntl_bits |= CCR_TXAK; + /* Do not generate stop on last byte */ + if (i2c->byte_posn == msg->len - 1) + i2c->cntl_bits |= CCR_MTX; + + writeccr(i2c, i2c->cntl_bits); + } + + byte = readb(i2c->base + MPC_I2C_DR); + + if (i2c->byte_posn == 0 && recv_len) { + if (byte == 0 || byte > I2C_SMBUS_BLOCK_MAX) { + mpc_i2c_finish(i2c, -EPROTO); + return; + } + msg->len += byte; + /* + * For block reads, generate Tx ACK here if data length + * is 1 byte (total length is 2 bytes). + */ + if (msg->len == 2) { + i2c->cntl_bits |= CCR_TXAK; + writeccr(i2c, i2c->cntl_bits); + } + } + + dev_dbg(i2c->dev, "%s %02x\n", action_str[i2c->action], byte); + msg->buf[i2c->byte_posn++] = byte; + break; + + case MPC_I2C_ACTION_WRITE: + dev_dbg(i2c->dev, "%s %02x\n", action_str[i2c->action], + msg->buf[i2c->byte_posn]); + writeb(msg->buf[i2c->byte_posn++], i2c->base + MPC_I2C_DR); + i2c->expect_rxack = 1; + break; + + case MPC_I2C_ACTION_STOP: + mpc_i2c_finish(i2c, 0); + break; + + default: + WARN(1, "Unexpected action %d\n", i2c->action); + break; + } + + if (msg && msg->len == i2c->byte_posn) { + i2c->curr_msg++; + i2c->byte_posn = 0; + + if (i2c->curr_msg == i2c->num_msgs) { + i2c->action = MPC_I2C_ACTION_STOP; + /* + * We don't get another interrupt on read so + * finish the transfer now + */ + if (dir) + mpc_i2c_finish(i2c, 0); + } else { + i2c->action = MPC_I2C_ACTION_RESTART; + } + } +} + +static void mpc_i2c_do_intr(struct mpc_i2c *i2c, u8 status) +{ + spin_lock(&i2c->lock); + + if (!(status & CSR_MCF)) { + dev_dbg(i2c->dev, "unfinished\n"); + mpc_i2c_finish(i2c, -EIO); + goto out; + } + + if (status & CSR_MAL) { + dev_dbg(i2c->dev, "arbitration lost\n"); + mpc_i2c_finish(i2c, -EAGAIN); + goto out; + } + + if (i2c->expect_rxack && (status & CSR_RXAK)) { + dev_dbg(i2c->dev, "no Rx ACK\n"); + mpc_i2c_finish(i2c, -ENXIO); + goto out; + } + i2c->expect_rxack = 0; + + mpc_i2c_do_action(i2c); + +out: + spin_unlock(&i2c->lock); +} + +static irqreturn_t mpc_i2c_isr(int irq, void *dev_id) +{ + struct mpc_i2c *i2c = dev_id; + u8 status; + + status = readb(i2c->base + MPC_I2C_SR); + if (status & CSR_MIF) { + /* Wait up to 100us for transfer to properly complete */ + readb_poll_timeout_atomic(i2c->base + MPC_I2C_SR, status, status & CSR_MCF, 0, 100); + writeb(0, i2c->base + MPC_I2C_SR); + mpc_i2c_do_intr(i2c, status); + return IRQ_HANDLED; + } + return IRQ_NONE; +} + +static int mpc_i2c_wait_for_completion(struct mpc_i2c *i2c) +{ + long time_left; + + time_left = wait_event_timeout(i2c->waitq, !i2c->block, i2c->adap.timeout); + if (!time_left) + return -ETIMEDOUT; + if (time_left < 0) + return time_left; + + return 0; +} + +static int mpc_i2c_execute_msg(struct mpc_i2c *i2c) +{ + unsigned long orig_jiffies; + unsigned long flags; + int ret; + + spin_lock_irqsave(&i2c->lock, flags); + + i2c->curr_msg = 0; + i2c->rc = 0; + i2c->byte_posn = 0; + i2c->block = 1; + i2c->action = MPC_I2C_ACTION_START; + + i2c->cntl_bits = CCR_MEN | CCR_MIEN; + writeb(0, i2c->base + MPC_I2C_SR); + writeccr(i2c, i2c->cntl_bits); + + mpc_i2c_do_action(i2c); + + spin_unlock_irqrestore(&i2c->lock, flags); + + ret = mpc_i2c_wait_for_completion(i2c); + if (ret) + i2c->rc = ret; + + if (i2c->rc == -EIO || i2c->rc == -EAGAIN || i2c->rc == -ETIMEDOUT) + i2c_recover_bus(&i2c->adap); + + orig_jiffies = jiffies; + /* Wait until STOP is seen, allow up to 1 s */ + while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) { + if (time_after(jiffies, orig_jiffies + HZ)) { + u8 status = readb(i2c->base + MPC_I2C_SR); + + dev_dbg(i2c->dev, "timeout\n"); + if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) { + writeb(status & ~CSR_MAL, + i2c->base + MPC_I2C_SR); + i2c_recover_bus(&i2c->adap); + } + return -EIO; + } + cond_resched(); + } + + return i2c->rc; +} + +static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + int rc, ret = num; + struct mpc_i2c *i2c = i2c_get_adapdata(adap); + int i; + + dev_dbg(i2c->dev, "num = %d\n", num); + for (i = 0; i < num; i++) + dev_dbg(i2c->dev, " addr = %02x, flags = %02x, len = %d, %*ph\n", + msgs[i].addr, msgs[i].flags, msgs[i].len, + msgs[i].flags & I2C_M_RD ? 0 : msgs[i].len, + msgs[i].buf); + + WARN_ON(i2c->msgs != NULL); + i2c->msgs = msgs; + i2c->num_msgs = num; + + rc = mpc_i2c_execute_msg(i2c); + if (rc < 0) + ret = rc; + + i2c->num_msgs = 0; + i2c->msgs = NULL; + + return ret; +} + +static u32 mpc_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL + | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL; +} + +static int fsl_i2c_bus_recovery(struct i2c_adapter *adap) +{ + struct mpc_i2c *i2c = i2c_get_adapdata(adap); + + if (i2c->has_errata_A004447) + mpc_i2c_fixup_A004447(i2c); + else + mpc_i2c_fixup(i2c); + + return 0; +} + +static const struct i2c_algorithm mpc_algo = { + .master_xfer = mpc_xfer, + .functionality = mpc_functionality, +}; + +static struct i2c_adapter mpc_ops = { + .owner = THIS_MODULE, + .algo = &mpc_algo, +}; + +static struct i2c_bus_recovery_info fsl_i2c_recovery_info = { + .recover_bus = fsl_i2c_bus_recovery, +}; + +static int fsl_i2c_probe(struct platform_device *op) +{ + const struct mpc_i2c_data *data; + struct mpc_i2c *i2c; + struct clk *clk; + int result; + u32 clock; + int err; + + i2c = devm_kzalloc(&op->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->dev = &op->dev; /* for debug and error output */ + + init_waitqueue_head(&i2c->waitq); + spin_lock_init(&i2c->lock); + + i2c->base = devm_platform_ioremap_resource(op, 0); + if (IS_ERR(i2c->base)) + return PTR_ERR(i2c->base); + + i2c->irq = platform_get_irq(op, 0); + if (i2c->irq < 0) + return i2c->irq; + + result = devm_request_irq(&op->dev, i2c->irq, mpc_i2c_isr, + IRQF_SHARED, "i2c-mpc", i2c); + if (result < 0) { + dev_err(i2c->dev, "failed to attach interrupt\n"); + return result; + } + + /* + * enable clock for the I2C peripheral (non fatal), + * keep a reference upon successful allocation + */ + clk = devm_clk_get_optional(&op->dev, NULL); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + err = clk_prepare_enable(clk); + if (err) { + dev_err(&op->dev, "failed to enable clock\n"); + return err; + } + + i2c->clk_per = clk; + + if (of_property_read_bool(op->dev.of_node, "fsl,preserve-clocking")) { + clock = MPC_I2C_CLOCK_PRESERVE; + } else { + result = of_property_read_u32(op->dev.of_node, + "clock-frequency", &clock); + if (result) + clock = MPC_I2C_CLOCK_LEGACY; + } + + data = device_get_match_data(&op->dev); + if (data) { + data->setup(op->dev.of_node, i2c, clock); + } else { + /* Backwards compatibility */ + if (of_property_read_bool(op->dev.of_node, "dfsrr")) + mpc_i2c_setup_8xxx(op->dev.of_node, i2c, clock); + } + + /* + * "fsl,timeout" has been marked as deprecated and, to maintain + * backward compatibility, we will only look for it if + * "i2c-scl-clk-low-timeout-us" is not present. + */ + result = of_property_read_u32(op->dev.of_node, + "i2c-scl-clk-low-timeout-us", + &mpc_ops.timeout); + if (result == -EINVAL) + result = of_property_read_u32(op->dev.of_node, + "fsl,timeout", &mpc_ops.timeout); + + if (!result) { + mpc_ops.timeout *= HZ / 1000000; + if (mpc_ops.timeout < 5) + mpc_ops.timeout = 5; + } else { + mpc_ops.timeout = HZ; + } + + dev_info(i2c->dev, "timeout %u us\n", mpc_ops.timeout * 1000000 / HZ); + + if (of_property_read_bool(op->dev.of_node, "fsl,i2c-erratum-a004447")) + i2c->has_errata_A004447 = true; + + i2c->adap = mpc_ops; + scnprintf(i2c->adap.name, sizeof(i2c->adap.name), + "MPC adapter (%s)", of_node_full_name(op->dev.of_node)); + i2c->adap.dev.parent = &op->dev; + i2c->adap.nr = op->id; + i2c->adap.dev.of_node = of_node_get(op->dev.of_node); + i2c->adap.bus_recovery_info = &fsl_i2c_recovery_info; + platform_set_drvdata(op, i2c); + i2c_set_adapdata(&i2c->adap, i2c); + + result = i2c_add_numbered_adapter(&i2c->adap); + if (result) + goto fail_add; + + return 0; + + fail_add: + clk_disable_unprepare(i2c->clk_per); + + return result; +}; + +static void fsl_i2c_remove(struct platform_device *op) +{ + struct mpc_i2c *i2c = platform_get_drvdata(op); + + i2c_del_adapter(&i2c->adap); + + clk_disable_unprepare(i2c->clk_per); +}; + +static int __maybe_unused mpc_i2c_suspend(struct device *dev) +{ + struct mpc_i2c *i2c = dev_get_drvdata(dev); + + i2c->fdr = readb(i2c->base + MPC_I2C_FDR); + i2c->dfsrr = readb(i2c->base + MPC_I2C_DFSRR); + + return 0; +} + +static int __maybe_unused mpc_i2c_resume(struct device *dev) +{ + struct mpc_i2c *i2c = dev_get_drvdata(dev); + + writeb(i2c->fdr, i2c->base + MPC_I2C_FDR); + writeb(i2c->dfsrr, i2c->base + MPC_I2C_DFSRR); + + return 0; +} +static SIMPLE_DEV_PM_OPS(mpc_i2c_pm_ops, mpc_i2c_suspend, mpc_i2c_resume); + +static const struct mpc_i2c_data mpc_i2c_data_512x = { + .setup = mpc_i2c_setup_512x, +}; + +static const struct mpc_i2c_data mpc_i2c_data_52xx = { + .setup = mpc_i2c_setup_52xx, +}; + +static const struct mpc_i2c_data mpc_i2c_data_8313 = { + .setup = mpc_i2c_setup_8xxx, +}; + +static const struct mpc_i2c_data mpc_i2c_data_8543 = { + .setup = mpc_i2c_setup_8xxx, +}; + +static const struct mpc_i2c_data mpc_i2c_data_8544 = { + .setup = mpc_i2c_setup_8xxx, +}; + +static const struct of_device_id mpc_i2c_of_match[] = { + {.compatible = "mpc5200-i2c", .data = &mpc_i2c_data_52xx, }, + {.compatible = "fsl,mpc5200b-i2c", .data = &mpc_i2c_data_52xx, }, + {.compatible = "fsl,mpc5200-i2c", .data = &mpc_i2c_data_52xx, }, + {.compatible = "fsl,mpc5121-i2c", .data = &mpc_i2c_data_512x, }, + {.compatible = "fsl,mpc8313-i2c", .data = &mpc_i2c_data_8313, }, + {.compatible = "fsl,mpc8543-i2c", .data = &mpc_i2c_data_8543, }, + {.compatible = "fsl,mpc8544-i2c", .data = &mpc_i2c_data_8544, }, + /* Backward compatibility */ + {.compatible = "fsl-i2c", }, + {}, +}; +MODULE_DEVICE_TABLE(of, mpc_i2c_of_match); + +/* Structure for a device driver */ +static struct platform_driver mpc_i2c_driver = { + .probe = fsl_i2c_probe, + .remove_new = fsl_i2c_remove, + .driver = { + .name = DRV_NAME, + .of_match_table = mpc_i2c_of_match, + .pm = &mpc_i2c_pm_ops, + }, +}; + +module_platform_driver(mpc_i2c_driver); + +MODULE_AUTHOR("Adrian Cox <adrian@humboldt.co.uk>"); +MODULE_DESCRIPTION("I2C-Bus adapter for MPC107 bridge and " + "MPC824x/83xx/85xx/86xx/512x/52xx processors"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c new file mode 100644 index 000000000..1a9b5a068 --- /dev/null +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -0,0 +1,1564 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2014 MediaTek Inc. + * Author: Xudong Chen <xudong.chen@mediatek.com> + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/scatterlist.h> +#include <linux/sched.h> +#include <linux/slab.h> + +#define I2C_RS_TRANSFER (1 << 4) +#define I2C_ARB_LOST (1 << 3) +#define I2C_HS_NACKERR (1 << 2) +#define I2C_ACKERR (1 << 1) +#define I2C_TRANSAC_COMP (1 << 0) +#define I2C_TRANSAC_START (1 << 0) +#define I2C_RS_MUL_CNFG (1 << 15) +#define I2C_RS_MUL_TRIG (1 << 14) +#define I2C_DCM_DISABLE 0x0000 +#define I2C_IO_CONFIG_OPEN_DRAIN 0x0003 +#define I2C_IO_CONFIG_PUSH_PULL 0x0000 +#define I2C_SOFT_RST 0x0001 +#define I2C_HANDSHAKE_RST 0x0020 +#define I2C_FIFO_ADDR_CLR 0x0001 +#define I2C_DELAY_LEN 0x0002 +#define I2C_ST_START_CON 0x8001 +#define I2C_FS_START_CON 0x1800 +#define I2C_TIME_CLR_VALUE 0x0000 +#define I2C_TIME_DEFAULT_VALUE 0x0003 +#define I2C_WRRD_TRANAC_VALUE 0x0002 +#define I2C_RD_TRANAC_VALUE 0x0001 +#define I2C_SCL_MIS_COMP_VALUE 0x0000 +#define I2C_CHN_CLR_FLAG 0x0000 +#define I2C_RELIABILITY 0x0010 +#define I2C_DMAACK_ENABLE 0x0008 + +#define I2C_DMA_CON_TX 0x0000 +#define I2C_DMA_CON_RX 0x0001 +#define I2C_DMA_ASYNC_MODE 0x0004 +#define I2C_DMA_SKIP_CONFIG 0x0010 +#define I2C_DMA_DIR_CHANGE 0x0200 +#define I2C_DMA_START_EN 0x0001 +#define I2C_DMA_INT_FLAG_NONE 0x0000 +#define I2C_DMA_CLR_FLAG 0x0000 +#define I2C_DMA_WARM_RST 0x0001 +#define I2C_DMA_HARD_RST 0x0002 +#define I2C_DMA_HANDSHAKE_RST 0x0004 + +#define MAX_SAMPLE_CNT_DIV 8 +#define MAX_STEP_CNT_DIV 64 +#define MAX_CLOCK_DIV_8BITS 256 +#define MAX_CLOCK_DIV_5BITS 32 +#define MAX_HS_STEP_CNT_DIV 8 +#define I2C_STANDARD_MODE_BUFFER (1000 / 3) +#define I2C_FAST_MODE_BUFFER (300 / 3) +#define I2C_FAST_MODE_PLUS_BUFFER (20 / 3) + +#define I2C_CONTROL_RS (0x1 << 1) +#define I2C_CONTROL_DMA_EN (0x1 << 2) +#define I2C_CONTROL_CLK_EXT_EN (0x1 << 3) +#define I2C_CONTROL_DIR_CHANGE (0x1 << 4) +#define I2C_CONTROL_ACKERR_DET_EN (0x1 << 5) +#define I2C_CONTROL_TRANSFER_LEN_CHANGE (0x1 << 6) +#define I2C_CONTROL_DMAACK_EN (0x1 << 8) +#define I2C_CONTROL_ASYNC_MODE (0x1 << 9) +#define I2C_CONTROL_WRAPPER (0x1 << 0) + +#define I2C_DRV_NAME "i2c-mt65xx" + +/** + * enum i2c_mt65xx_clks - Clocks enumeration for MT65XX I2C + * + * @I2C_MT65XX_CLK_MAIN: main clock for i2c bus + * @I2C_MT65XX_CLK_DMA: DMA clock for i2c via DMA + * @I2C_MT65XX_CLK_PMIC: PMIC clock for i2c from PMIC + * @I2C_MT65XX_CLK_ARB: Arbitrator clock for i2c + * @I2C_MT65XX_CLK_MAX: Number of supported clocks + */ +enum i2c_mt65xx_clks { + I2C_MT65XX_CLK_MAIN = 0, + I2C_MT65XX_CLK_DMA, + I2C_MT65XX_CLK_PMIC, + I2C_MT65XX_CLK_ARB, + I2C_MT65XX_CLK_MAX +}; + +static const char * const i2c_mt65xx_clk_ids[I2C_MT65XX_CLK_MAX] = { + "main", "dma", "pmic", "arb" +}; + +enum DMA_REGS_OFFSET { + OFFSET_INT_FLAG = 0x0, + OFFSET_INT_EN = 0x04, + OFFSET_EN = 0x08, + OFFSET_RST = 0x0c, + OFFSET_CON = 0x18, + OFFSET_TX_MEM_ADDR = 0x1c, + OFFSET_RX_MEM_ADDR = 0x20, + OFFSET_TX_LEN = 0x24, + OFFSET_RX_LEN = 0x28, + OFFSET_TX_4G_MODE = 0x54, + OFFSET_RX_4G_MODE = 0x58, +}; + +enum i2c_trans_st_rs { + I2C_TRANS_STOP = 0, + I2C_TRANS_REPEATED_START, +}; + +enum mtk_trans_op { + I2C_MASTER_WR = 1, + I2C_MASTER_RD, + I2C_MASTER_WRRD, +}; + +enum I2C_REGS_OFFSET { + OFFSET_DATA_PORT, + OFFSET_SLAVE_ADDR, + OFFSET_INTR_MASK, + OFFSET_INTR_STAT, + OFFSET_CONTROL, + OFFSET_TRANSFER_LEN, + OFFSET_TRANSAC_LEN, + OFFSET_DELAY_LEN, + OFFSET_TIMING, + OFFSET_START, + OFFSET_EXT_CONF, + OFFSET_FIFO_STAT, + OFFSET_FIFO_THRESH, + OFFSET_FIFO_ADDR_CLR, + OFFSET_IO_CONFIG, + OFFSET_RSV_DEBUG, + OFFSET_HS, + OFFSET_SOFTRESET, + OFFSET_DCM_EN, + OFFSET_MULTI_DMA, + OFFSET_PATH_DIR, + OFFSET_DEBUGSTAT, + OFFSET_DEBUGCTRL, + OFFSET_TRANSFER_LEN_AUX, + OFFSET_CLOCK_DIV, + OFFSET_LTIMING, + OFFSET_SCL_HIGH_LOW_RATIO, + OFFSET_HS_SCL_HIGH_LOW_RATIO, + OFFSET_SCL_MIS_COMP_POINT, + OFFSET_STA_STO_AC_TIMING, + OFFSET_HS_STA_STO_AC_TIMING, + OFFSET_SDA_TIMING, +}; + +static const u16 mt_i2c_regs_v1[] = { + [OFFSET_DATA_PORT] = 0x0, + [OFFSET_SLAVE_ADDR] = 0x4, + [OFFSET_INTR_MASK] = 0x8, + [OFFSET_INTR_STAT] = 0xc, + [OFFSET_CONTROL] = 0x10, + [OFFSET_TRANSFER_LEN] = 0x14, + [OFFSET_TRANSAC_LEN] = 0x18, + [OFFSET_DELAY_LEN] = 0x1c, + [OFFSET_TIMING] = 0x20, + [OFFSET_START] = 0x24, + [OFFSET_EXT_CONF] = 0x28, + [OFFSET_FIFO_STAT] = 0x30, + [OFFSET_FIFO_THRESH] = 0x34, + [OFFSET_FIFO_ADDR_CLR] = 0x38, + [OFFSET_IO_CONFIG] = 0x40, + [OFFSET_RSV_DEBUG] = 0x44, + [OFFSET_HS] = 0x48, + [OFFSET_SOFTRESET] = 0x50, + [OFFSET_DCM_EN] = 0x54, + [OFFSET_PATH_DIR] = 0x60, + [OFFSET_DEBUGSTAT] = 0x64, + [OFFSET_DEBUGCTRL] = 0x68, + [OFFSET_TRANSFER_LEN_AUX] = 0x6c, + [OFFSET_CLOCK_DIV] = 0x70, + [OFFSET_SCL_HIGH_LOW_RATIO] = 0x74, + [OFFSET_HS_SCL_HIGH_LOW_RATIO] = 0x78, + [OFFSET_SCL_MIS_COMP_POINT] = 0x7C, + [OFFSET_STA_STO_AC_TIMING] = 0x80, + [OFFSET_HS_STA_STO_AC_TIMING] = 0x84, + [OFFSET_SDA_TIMING] = 0x88, +}; + +static const u16 mt_i2c_regs_v2[] = { + [OFFSET_DATA_PORT] = 0x0, + [OFFSET_SLAVE_ADDR] = 0x4, + [OFFSET_INTR_MASK] = 0x8, + [OFFSET_INTR_STAT] = 0xc, + [OFFSET_CONTROL] = 0x10, + [OFFSET_TRANSFER_LEN] = 0x14, + [OFFSET_TRANSAC_LEN] = 0x18, + [OFFSET_DELAY_LEN] = 0x1c, + [OFFSET_TIMING] = 0x20, + [OFFSET_START] = 0x24, + [OFFSET_EXT_CONF] = 0x28, + [OFFSET_LTIMING] = 0x2c, + [OFFSET_HS] = 0x30, + [OFFSET_IO_CONFIG] = 0x34, + [OFFSET_FIFO_ADDR_CLR] = 0x38, + [OFFSET_SDA_TIMING] = 0x3c, + [OFFSET_TRANSFER_LEN_AUX] = 0x44, + [OFFSET_CLOCK_DIV] = 0x48, + [OFFSET_SOFTRESET] = 0x50, + [OFFSET_MULTI_DMA] = 0x8c, + [OFFSET_SCL_MIS_COMP_POINT] = 0x90, + [OFFSET_DEBUGSTAT] = 0xe4, + [OFFSET_DEBUGCTRL] = 0xe8, + [OFFSET_FIFO_STAT] = 0xf4, + [OFFSET_FIFO_THRESH] = 0xf8, + [OFFSET_DCM_EN] = 0xf88, +}; + +static const u16 mt_i2c_regs_v3[] = { + [OFFSET_DATA_PORT] = 0x0, + [OFFSET_INTR_MASK] = 0x8, + [OFFSET_INTR_STAT] = 0xc, + [OFFSET_CONTROL] = 0x10, + [OFFSET_TRANSFER_LEN] = 0x14, + [OFFSET_TRANSAC_LEN] = 0x18, + [OFFSET_DELAY_LEN] = 0x1c, + [OFFSET_TIMING] = 0x20, + [OFFSET_START] = 0x24, + [OFFSET_EXT_CONF] = 0x28, + [OFFSET_LTIMING] = 0x2c, + [OFFSET_HS] = 0x30, + [OFFSET_IO_CONFIG] = 0x34, + [OFFSET_FIFO_ADDR_CLR] = 0x38, + [OFFSET_SDA_TIMING] = 0x3c, + [OFFSET_TRANSFER_LEN_AUX] = 0x44, + [OFFSET_CLOCK_DIV] = 0x48, + [OFFSET_SOFTRESET] = 0x50, + [OFFSET_MULTI_DMA] = 0x8c, + [OFFSET_SCL_MIS_COMP_POINT] = 0x90, + [OFFSET_SLAVE_ADDR] = 0x94, + [OFFSET_DEBUGSTAT] = 0xe4, + [OFFSET_DEBUGCTRL] = 0xe8, + [OFFSET_FIFO_STAT] = 0xf4, + [OFFSET_FIFO_THRESH] = 0xf8, + [OFFSET_DCM_EN] = 0xf88, +}; + +struct mtk_i2c_compatible { + const struct i2c_adapter_quirks *quirks; + const u16 *regs; + unsigned char pmic_i2c: 1; + unsigned char dcm: 1; + unsigned char auto_restart: 1; + unsigned char aux_len_reg: 1; + unsigned char timing_adjust: 1; + unsigned char dma_sync: 1; + unsigned char ltiming_adjust: 1; + unsigned char apdma_sync: 1; + unsigned char max_dma_support; +}; + +struct mtk_i2c_ac_timing { + u16 htiming; + u16 ltiming; + u16 hs; + u16 ext; + u16 inter_clk_div; + u16 scl_hl_ratio; + u16 hs_scl_hl_ratio; + u16 sta_stop; + u16 hs_sta_stop; + u16 sda_timing; +}; + +struct mtk_i2c { + struct i2c_adapter adap; /* i2c host adapter */ + struct device *dev; + struct completion msg_complete; + struct i2c_timings timing_info; + + /* set in i2c probe */ + void __iomem *base; /* i2c base addr */ + void __iomem *pdmabase; /* dma base address*/ + struct clk_bulk_data clocks[I2C_MT65XX_CLK_MAX]; /* clocks for i2c */ + bool have_pmic; /* can use i2c pins from PMIC */ + bool use_push_pull; /* IO config push-pull mode */ + + u16 irq_stat; /* interrupt status */ + unsigned int clk_src_div; + unsigned int speed_hz; /* The speed in transfer */ + enum mtk_trans_op op; + u16 timing_reg; + u16 high_speed_reg; + u16 ltiming_reg; + unsigned char auto_restart; + bool ignore_restart_irq; + struct mtk_i2c_ac_timing ac_timing; + const struct mtk_i2c_compatible *dev_comp; +}; + +/** + * struct i2c_spec_values: + * @min_low_ns: min LOW period of the SCL clock + * @min_su_sta_ns: min set-up time for a repeated START condition + * @max_hd_dat_ns: max data hold time + * @min_su_dat_ns: min data set-up time + */ +struct i2c_spec_values { + unsigned int min_low_ns; + unsigned int min_su_sta_ns; + unsigned int max_hd_dat_ns; + unsigned int min_su_dat_ns; +}; + +static const struct i2c_spec_values standard_mode_spec = { + .min_low_ns = 4700 + I2C_STANDARD_MODE_BUFFER, + .min_su_sta_ns = 4700 + I2C_STANDARD_MODE_BUFFER, + .max_hd_dat_ns = 3450 - I2C_STANDARD_MODE_BUFFER, + .min_su_dat_ns = 250 + I2C_STANDARD_MODE_BUFFER, +}; + +static const struct i2c_spec_values fast_mode_spec = { + .min_low_ns = 1300 + I2C_FAST_MODE_BUFFER, + .min_su_sta_ns = 600 + I2C_FAST_MODE_BUFFER, + .max_hd_dat_ns = 900 - I2C_FAST_MODE_BUFFER, + .min_su_dat_ns = 100 + I2C_FAST_MODE_BUFFER, +}; + +static const struct i2c_spec_values fast_mode_plus_spec = { + .min_low_ns = 500 + I2C_FAST_MODE_PLUS_BUFFER, + .min_su_sta_ns = 260 + I2C_FAST_MODE_PLUS_BUFFER, + .max_hd_dat_ns = 400 - I2C_FAST_MODE_PLUS_BUFFER, + .min_su_dat_ns = 50 + I2C_FAST_MODE_PLUS_BUFFER, +}; + +static const struct i2c_adapter_quirks mt6577_i2c_quirks = { + .flags = I2C_AQ_COMB_WRITE_THEN_READ, + .max_num_msgs = 1, + .max_write_len = 255, + .max_read_len = 255, + .max_comb_1st_msg_len = 255, + .max_comb_2nd_msg_len = 31, +}; + +static const struct i2c_adapter_quirks mt7622_i2c_quirks = { + .max_num_msgs = 255, +}; + +static const struct i2c_adapter_quirks mt8183_i2c_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN, +}; + +static const struct mtk_i2c_compatible mt2712_compat = { + .regs = mt_i2c_regs_v1, + .pmic_i2c = 0, + .dcm = 1, + .auto_restart = 1, + .aux_len_reg = 1, + .timing_adjust = 1, + .dma_sync = 0, + .ltiming_adjust = 0, + .apdma_sync = 0, + .max_dma_support = 33, +}; + +static const struct mtk_i2c_compatible mt6577_compat = { + .quirks = &mt6577_i2c_quirks, + .regs = mt_i2c_regs_v1, + .pmic_i2c = 0, + .dcm = 1, + .auto_restart = 0, + .aux_len_reg = 0, + .timing_adjust = 0, + .dma_sync = 0, + .ltiming_adjust = 0, + .apdma_sync = 0, + .max_dma_support = 32, +}; + +static const struct mtk_i2c_compatible mt6589_compat = { + .quirks = &mt6577_i2c_quirks, + .regs = mt_i2c_regs_v1, + .pmic_i2c = 1, + .dcm = 0, + .auto_restart = 0, + .aux_len_reg = 0, + .timing_adjust = 0, + .dma_sync = 0, + .ltiming_adjust = 0, + .apdma_sync = 0, + .max_dma_support = 32, +}; + +static const struct mtk_i2c_compatible mt7622_compat = { + .quirks = &mt7622_i2c_quirks, + .regs = mt_i2c_regs_v1, + .pmic_i2c = 0, + .dcm = 1, + .auto_restart = 1, + .aux_len_reg = 1, + .timing_adjust = 0, + .dma_sync = 0, + .ltiming_adjust = 0, + .apdma_sync = 0, + .max_dma_support = 32, +}; + +static const struct mtk_i2c_compatible mt8168_compat = { + .regs = mt_i2c_regs_v1, + .pmic_i2c = 0, + .dcm = 1, + .auto_restart = 1, + .aux_len_reg = 1, + .timing_adjust = 1, + .dma_sync = 1, + .ltiming_adjust = 0, + .apdma_sync = 0, + .max_dma_support = 33, +}; + +static const struct mtk_i2c_compatible mt7981_compat = { + .regs = mt_i2c_regs_v3, + .pmic_i2c = 0, + .dcm = 0, + .auto_restart = 1, + .aux_len_reg = 1, + .timing_adjust = 1, + .dma_sync = 1, + .ltiming_adjust = 1, + .max_dma_support = 33 +}; + +static const struct mtk_i2c_compatible mt7986_compat = { + .quirks = &mt7622_i2c_quirks, + .regs = mt_i2c_regs_v1, + .pmic_i2c = 0, + .dcm = 1, + .auto_restart = 1, + .aux_len_reg = 1, + .timing_adjust = 0, + .dma_sync = 1, + .ltiming_adjust = 0, + .max_dma_support = 32, +}; + +static const struct mtk_i2c_compatible mt8173_compat = { + .regs = mt_i2c_regs_v1, + .pmic_i2c = 0, + .dcm = 1, + .auto_restart = 1, + .aux_len_reg = 1, + .timing_adjust = 0, + .dma_sync = 0, + .ltiming_adjust = 0, + .apdma_sync = 0, + .max_dma_support = 33, +}; + +static const struct mtk_i2c_compatible mt8183_compat = { + .quirks = &mt8183_i2c_quirks, + .regs = mt_i2c_regs_v2, + .pmic_i2c = 0, + .dcm = 0, + .auto_restart = 1, + .aux_len_reg = 1, + .timing_adjust = 1, + .dma_sync = 1, + .ltiming_adjust = 1, + .apdma_sync = 0, + .max_dma_support = 33, +}; + +static const struct mtk_i2c_compatible mt8186_compat = { + .regs = mt_i2c_regs_v2, + .pmic_i2c = 0, + .dcm = 0, + .auto_restart = 1, + .aux_len_reg = 1, + .timing_adjust = 1, + .dma_sync = 0, + .ltiming_adjust = 1, + .apdma_sync = 0, + .max_dma_support = 36, +}; + +static const struct mtk_i2c_compatible mt8188_compat = { + .regs = mt_i2c_regs_v3, + .pmic_i2c = 0, + .dcm = 0, + .auto_restart = 1, + .aux_len_reg = 1, + .timing_adjust = 1, + .dma_sync = 0, + .ltiming_adjust = 1, + .apdma_sync = 1, + .max_dma_support = 36, +}; + +static const struct mtk_i2c_compatible mt8192_compat = { + .quirks = &mt8183_i2c_quirks, + .regs = mt_i2c_regs_v2, + .pmic_i2c = 0, + .dcm = 0, + .auto_restart = 1, + .aux_len_reg = 1, + .timing_adjust = 1, + .dma_sync = 1, + .ltiming_adjust = 1, + .apdma_sync = 1, + .max_dma_support = 36, +}; + +static const struct of_device_id mtk_i2c_of_match[] = { + { .compatible = "mediatek,mt2712-i2c", .data = &mt2712_compat }, + { .compatible = "mediatek,mt6577-i2c", .data = &mt6577_compat }, + { .compatible = "mediatek,mt6589-i2c", .data = &mt6589_compat }, + { .compatible = "mediatek,mt7622-i2c", .data = &mt7622_compat }, + { .compatible = "mediatek,mt7981-i2c", .data = &mt7981_compat }, + { .compatible = "mediatek,mt7986-i2c", .data = &mt7986_compat }, + { .compatible = "mediatek,mt8168-i2c", .data = &mt8168_compat }, + { .compatible = "mediatek,mt8173-i2c", .data = &mt8173_compat }, + { .compatible = "mediatek,mt8183-i2c", .data = &mt8183_compat }, + { .compatible = "mediatek,mt8186-i2c", .data = &mt8186_compat }, + { .compatible = "mediatek,mt8188-i2c", .data = &mt8188_compat }, + { .compatible = "mediatek,mt8192-i2c", .data = &mt8192_compat }, + {} +}; +MODULE_DEVICE_TABLE(of, mtk_i2c_of_match); + +static u16 mtk_i2c_readw(struct mtk_i2c *i2c, enum I2C_REGS_OFFSET reg) +{ + return readw(i2c->base + i2c->dev_comp->regs[reg]); +} + +static void mtk_i2c_writew(struct mtk_i2c *i2c, u16 val, + enum I2C_REGS_OFFSET reg) +{ + writew(val, i2c->base + i2c->dev_comp->regs[reg]); +} + +static void mtk_i2c_init_hw(struct mtk_i2c *i2c) +{ + u16 control_reg; + u16 intr_stat_reg; + u16 ext_conf_val; + + mtk_i2c_writew(i2c, I2C_CHN_CLR_FLAG, OFFSET_START); + intr_stat_reg = mtk_i2c_readw(i2c, OFFSET_INTR_STAT); + mtk_i2c_writew(i2c, intr_stat_reg, OFFSET_INTR_STAT); + + if (i2c->dev_comp->apdma_sync) { + writel(I2C_DMA_WARM_RST, i2c->pdmabase + OFFSET_RST); + udelay(10); + writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); + udelay(10); + writel(I2C_DMA_HANDSHAKE_RST | I2C_DMA_HARD_RST, + i2c->pdmabase + OFFSET_RST); + mtk_i2c_writew(i2c, I2C_HANDSHAKE_RST | I2C_SOFT_RST, + OFFSET_SOFTRESET); + udelay(10); + writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); + mtk_i2c_writew(i2c, I2C_CHN_CLR_FLAG, OFFSET_SOFTRESET); + } else { + writel(I2C_DMA_HARD_RST, i2c->pdmabase + OFFSET_RST); + udelay(50); + writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); + mtk_i2c_writew(i2c, I2C_SOFT_RST, OFFSET_SOFTRESET); + } + + /* Set ioconfig */ + if (i2c->use_push_pull) + mtk_i2c_writew(i2c, I2C_IO_CONFIG_PUSH_PULL, OFFSET_IO_CONFIG); + else + mtk_i2c_writew(i2c, I2C_IO_CONFIG_OPEN_DRAIN, OFFSET_IO_CONFIG); + + if (i2c->dev_comp->dcm) + mtk_i2c_writew(i2c, I2C_DCM_DISABLE, OFFSET_DCM_EN); + + mtk_i2c_writew(i2c, i2c->timing_reg, OFFSET_TIMING); + mtk_i2c_writew(i2c, i2c->high_speed_reg, OFFSET_HS); + if (i2c->dev_comp->ltiming_adjust) + mtk_i2c_writew(i2c, i2c->ltiming_reg, OFFSET_LTIMING); + + if (i2c->speed_hz <= I2C_MAX_STANDARD_MODE_FREQ) + ext_conf_val = I2C_ST_START_CON; + else + ext_conf_val = I2C_FS_START_CON; + + if (i2c->dev_comp->timing_adjust) { + ext_conf_val = i2c->ac_timing.ext; + mtk_i2c_writew(i2c, i2c->ac_timing.inter_clk_div, + OFFSET_CLOCK_DIV); + mtk_i2c_writew(i2c, I2C_SCL_MIS_COMP_VALUE, + OFFSET_SCL_MIS_COMP_POINT); + mtk_i2c_writew(i2c, i2c->ac_timing.sda_timing, + OFFSET_SDA_TIMING); + + if (i2c->dev_comp->ltiming_adjust) { + mtk_i2c_writew(i2c, i2c->ac_timing.htiming, + OFFSET_TIMING); + mtk_i2c_writew(i2c, i2c->ac_timing.hs, OFFSET_HS); + mtk_i2c_writew(i2c, i2c->ac_timing.ltiming, + OFFSET_LTIMING); + } else { + mtk_i2c_writew(i2c, i2c->ac_timing.scl_hl_ratio, + OFFSET_SCL_HIGH_LOW_RATIO); + mtk_i2c_writew(i2c, i2c->ac_timing.hs_scl_hl_ratio, + OFFSET_HS_SCL_HIGH_LOW_RATIO); + mtk_i2c_writew(i2c, i2c->ac_timing.sta_stop, + OFFSET_STA_STO_AC_TIMING); + mtk_i2c_writew(i2c, i2c->ac_timing.hs_sta_stop, + OFFSET_HS_STA_STO_AC_TIMING); + } + } + mtk_i2c_writew(i2c, ext_conf_val, OFFSET_EXT_CONF); + + /* If use i2c pin from PMIC mt6397 side, need set PATH_DIR first */ + if (i2c->have_pmic) + mtk_i2c_writew(i2c, I2C_CONTROL_WRAPPER, OFFSET_PATH_DIR); + + control_reg = I2C_CONTROL_ACKERR_DET_EN | + I2C_CONTROL_CLK_EXT_EN | I2C_CONTROL_DMA_EN; + if (i2c->dev_comp->dma_sync) + control_reg |= I2C_CONTROL_DMAACK_EN | I2C_CONTROL_ASYNC_MODE; + + mtk_i2c_writew(i2c, control_reg, OFFSET_CONTROL); + mtk_i2c_writew(i2c, I2C_DELAY_LEN, OFFSET_DELAY_LEN); +} + +static const struct i2c_spec_values *mtk_i2c_get_spec(unsigned int speed) +{ + if (speed <= I2C_MAX_STANDARD_MODE_FREQ) + return &standard_mode_spec; + else if (speed <= I2C_MAX_FAST_MODE_FREQ) + return &fast_mode_spec; + else + return &fast_mode_plus_spec; +} + +static int mtk_i2c_max_step_cnt(unsigned int target_speed) +{ + if (target_speed > I2C_MAX_FAST_MODE_PLUS_FREQ) + return MAX_HS_STEP_CNT_DIV; + else + return MAX_STEP_CNT_DIV; +} + +static int mtk_i2c_get_clk_div_restri(struct mtk_i2c *i2c, + unsigned int sample_cnt) +{ + int clk_div_restri = 0; + + if (i2c->dev_comp->ltiming_adjust == 0) + return 0; + + if (sample_cnt == 1) { + if (i2c->ac_timing.inter_clk_div == 0) + clk_div_restri = 0; + else + clk_div_restri = 1; + } else { + if (i2c->ac_timing.inter_clk_div == 0) + clk_div_restri = -1; + else if (i2c->ac_timing.inter_clk_div == 1) + clk_div_restri = 0; + else + clk_div_restri = 1; + } + + return clk_div_restri; +} + +/* + * Check and Calculate i2c ac-timing + * + * Hardware design: + * sample_ns = (1000000000 * (sample_cnt + 1)) / clk_src + * xxx_cnt_div = spec->min_xxx_ns / sample_ns + * + * Sample_ns is rounded down for xxx_cnt_div would be greater + * than the smallest spec. + * The sda_timing is chosen as the middle value between + * the largest and smallest. + */ +static int mtk_i2c_check_ac_timing(struct mtk_i2c *i2c, + unsigned int clk_src, + unsigned int check_speed, + unsigned int step_cnt, + unsigned int sample_cnt) +{ + const struct i2c_spec_values *spec; + unsigned int su_sta_cnt, low_cnt, high_cnt, max_step_cnt; + unsigned int sda_max, sda_min, clk_ns, max_sta_cnt = 0x3f; + unsigned int sample_ns = div_u64(1000000000ULL * (sample_cnt + 1), + clk_src); + + if (!i2c->dev_comp->timing_adjust) + return 0; + + if (i2c->dev_comp->ltiming_adjust) + max_sta_cnt = 0x100; + + spec = mtk_i2c_get_spec(check_speed); + + if (i2c->dev_comp->ltiming_adjust) + clk_ns = 1000000000 / clk_src; + else + clk_ns = sample_ns / 2; + + su_sta_cnt = DIV_ROUND_UP(spec->min_su_sta_ns + + i2c->timing_info.scl_int_delay_ns, clk_ns); + if (su_sta_cnt > max_sta_cnt) + return -1; + + low_cnt = DIV_ROUND_UP(spec->min_low_ns, sample_ns); + max_step_cnt = mtk_i2c_max_step_cnt(check_speed); + if ((2 * step_cnt) > low_cnt && low_cnt < max_step_cnt) { + if (low_cnt > step_cnt) { + high_cnt = 2 * step_cnt - low_cnt; + } else { + high_cnt = step_cnt; + low_cnt = step_cnt; + } + } else { + return -2; + } + + sda_max = spec->max_hd_dat_ns / sample_ns; + if (sda_max > low_cnt) + sda_max = 0; + + sda_min = DIV_ROUND_UP(spec->min_su_dat_ns, sample_ns); + if (sda_min < low_cnt) + sda_min = 0; + + if (sda_min > sda_max) + return -3; + + if (check_speed > I2C_MAX_FAST_MODE_PLUS_FREQ) { + if (i2c->dev_comp->ltiming_adjust) { + i2c->ac_timing.hs = I2C_TIME_DEFAULT_VALUE | + (sample_cnt << 12) | (high_cnt << 8); + i2c->ac_timing.ltiming &= ~GENMASK(15, 9); + i2c->ac_timing.ltiming |= (sample_cnt << 12) | + (low_cnt << 9); + i2c->ac_timing.ext &= ~GENMASK(7, 1); + i2c->ac_timing.ext |= (su_sta_cnt << 1) | (1 << 0); + } else { + i2c->ac_timing.hs_scl_hl_ratio = (1 << 12) | + (high_cnt << 6) | low_cnt; + i2c->ac_timing.hs_sta_stop = (su_sta_cnt << 8) | + su_sta_cnt; + } + i2c->ac_timing.sda_timing &= ~GENMASK(11, 6); + i2c->ac_timing.sda_timing |= (1 << 12) | + ((sda_max + sda_min) / 2) << 6; + } else { + if (i2c->dev_comp->ltiming_adjust) { + i2c->ac_timing.htiming = (sample_cnt << 8) | (high_cnt); + i2c->ac_timing.ltiming = (sample_cnt << 6) | (low_cnt); + i2c->ac_timing.ext = (su_sta_cnt << 8) | (1 << 0); + } else { + i2c->ac_timing.scl_hl_ratio = (1 << 12) | + (high_cnt << 6) | low_cnt; + i2c->ac_timing.sta_stop = (su_sta_cnt << 8) | + su_sta_cnt; + } + + i2c->ac_timing.sda_timing = (1 << 12) | + (sda_max + sda_min) / 2; + } + + return 0; +} + +/* + * Calculate i2c port speed + * + * Hardware design: + * i2c_bus_freq = parent_clk / (clock_div * 2 * sample_cnt * step_cnt) + * clock_div: fixed in hardware, but may be various in different SoCs + * + * The calculation want to pick the highest bus frequency that is still + * less than or equal to i2c->speed_hz. The calculation try to get + * sample_cnt and step_cn + */ +static int mtk_i2c_calculate_speed(struct mtk_i2c *i2c, unsigned int clk_src, + unsigned int target_speed, + unsigned int *timing_step_cnt, + unsigned int *timing_sample_cnt) +{ + unsigned int step_cnt; + unsigned int sample_cnt; + unsigned int max_step_cnt; + unsigned int base_sample_cnt = MAX_SAMPLE_CNT_DIV; + unsigned int base_step_cnt; + unsigned int opt_div; + unsigned int best_mul; + unsigned int cnt_mul; + int ret = -EINVAL; + int clk_div_restri = 0; + + if (target_speed > I2C_MAX_HIGH_SPEED_MODE_FREQ) + target_speed = I2C_MAX_HIGH_SPEED_MODE_FREQ; + + max_step_cnt = mtk_i2c_max_step_cnt(target_speed); + base_step_cnt = max_step_cnt; + /* Find the best combination */ + opt_div = DIV_ROUND_UP(clk_src >> 1, target_speed); + best_mul = MAX_SAMPLE_CNT_DIV * max_step_cnt; + + /* Search for the best pair (sample_cnt, step_cnt) with + * 0 < sample_cnt < MAX_SAMPLE_CNT_DIV + * 0 < step_cnt < max_step_cnt + * sample_cnt * step_cnt >= opt_div + * optimizing for sample_cnt * step_cnt being minimal + */ + for (sample_cnt = 1; sample_cnt <= MAX_SAMPLE_CNT_DIV; sample_cnt++) { + clk_div_restri = mtk_i2c_get_clk_div_restri(i2c, sample_cnt); + step_cnt = DIV_ROUND_UP(opt_div + clk_div_restri, sample_cnt); + cnt_mul = step_cnt * sample_cnt; + if (step_cnt > max_step_cnt) + continue; + + if (cnt_mul < best_mul) { + ret = mtk_i2c_check_ac_timing(i2c, clk_src, + target_speed, step_cnt - 1, sample_cnt - 1); + if (ret) + continue; + + best_mul = cnt_mul; + base_sample_cnt = sample_cnt; + base_step_cnt = step_cnt; + if (best_mul == (opt_div + clk_div_restri)) + break; + } + } + + if (ret) + return -EINVAL; + + sample_cnt = base_sample_cnt; + step_cnt = base_step_cnt; + + if ((clk_src / (2 * (sample_cnt * step_cnt - clk_div_restri))) > + target_speed) { + /* In this case, hardware can't support such + * low i2c_bus_freq + */ + dev_dbg(i2c->dev, "Unsupported speed (%uhz)\n", target_speed); + return -EINVAL; + } + + *timing_step_cnt = step_cnt - 1; + *timing_sample_cnt = sample_cnt - 1; + + return 0; +} + +static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int parent_clk) +{ + unsigned int clk_src; + unsigned int step_cnt; + unsigned int sample_cnt; + unsigned int l_step_cnt; + unsigned int l_sample_cnt; + unsigned int target_speed; + unsigned int clk_div; + unsigned int max_clk_div; + int ret; + + target_speed = i2c->speed_hz; + parent_clk /= i2c->clk_src_div; + + if (i2c->dev_comp->timing_adjust && i2c->dev_comp->ltiming_adjust) + max_clk_div = MAX_CLOCK_DIV_5BITS; + else if (i2c->dev_comp->timing_adjust) + max_clk_div = MAX_CLOCK_DIV_8BITS; + else + max_clk_div = 1; + + for (clk_div = 1; clk_div <= max_clk_div; clk_div++) { + clk_src = parent_clk / clk_div; + i2c->ac_timing.inter_clk_div = clk_div - 1; + + if (target_speed > I2C_MAX_FAST_MODE_PLUS_FREQ) { + /* Set master code speed register */ + ret = mtk_i2c_calculate_speed(i2c, clk_src, + I2C_MAX_FAST_MODE_FREQ, + &l_step_cnt, + &l_sample_cnt); + if (ret < 0) + continue; + + i2c->timing_reg = (l_sample_cnt << 8) | l_step_cnt; + + /* Set the high speed mode register */ + ret = mtk_i2c_calculate_speed(i2c, clk_src, + target_speed, &step_cnt, + &sample_cnt); + if (ret < 0) + continue; + + i2c->high_speed_reg = I2C_TIME_DEFAULT_VALUE | + (sample_cnt << 12) | (step_cnt << 8); + + if (i2c->dev_comp->ltiming_adjust) + i2c->ltiming_reg = + (l_sample_cnt << 6) | l_step_cnt | + (sample_cnt << 12) | (step_cnt << 9); + } else { + ret = mtk_i2c_calculate_speed(i2c, clk_src, + target_speed, &l_step_cnt, + &l_sample_cnt); + if (ret < 0) + continue; + + i2c->timing_reg = (l_sample_cnt << 8) | l_step_cnt; + + /* Disable the high speed transaction */ + i2c->high_speed_reg = I2C_TIME_CLR_VALUE; + + if (i2c->dev_comp->ltiming_adjust) + i2c->ltiming_reg = + (l_sample_cnt << 6) | l_step_cnt; + } + + break; + } + + + return 0; +} + +static void i2c_dump_register(struct mtk_i2c *i2c) +{ + dev_dbg(i2c->dev, "SLAVE_ADDR: 0x%x, INTR_MASK: 0x%x\n", + mtk_i2c_readw(i2c, OFFSET_SLAVE_ADDR), + mtk_i2c_readw(i2c, OFFSET_INTR_MASK)); + dev_dbg(i2c->dev, "INTR_STAT: 0x%x, CONTROL: 0x%x\n", + mtk_i2c_readw(i2c, OFFSET_INTR_STAT), + mtk_i2c_readw(i2c, OFFSET_CONTROL)); + dev_dbg(i2c->dev, "TRANSFER_LEN: 0x%x, TRANSAC_LEN: 0x%x\n", + mtk_i2c_readw(i2c, OFFSET_TRANSFER_LEN), + mtk_i2c_readw(i2c, OFFSET_TRANSAC_LEN)); + dev_dbg(i2c->dev, "DELAY_LEN: 0x%x, HTIMING: 0x%x\n", + mtk_i2c_readw(i2c, OFFSET_DELAY_LEN), + mtk_i2c_readw(i2c, OFFSET_TIMING)); + dev_dbg(i2c->dev, "START: 0x%x, EXT_CONF: 0x%x\n", + mtk_i2c_readw(i2c, OFFSET_START), + mtk_i2c_readw(i2c, OFFSET_EXT_CONF)); + dev_dbg(i2c->dev, "HS: 0x%x, IO_CONFIG: 0x%x\n", + mtk_i2c_readw(i2c, OFFSET_HS), + mtk_i2c_readw(i2c, OFFSET_IO_CONFIG)); + dev_dbg(i2c->dev, "DCM_EN: 0x%x, TRANSFER_LEN_AUX: 0x%x\n", + mtk_i2c_readw(i2c, OFFSET_DCM_EN), + mtk_i2c_readw(i2c, OFFSET_TRANSFER_LEN_AUX)); + dev_dbg(i2c->dev, "CLOCK_DIV: 0x%x, FIFO_STAT: 0x%x\n", + mtk_i2c_readw(i2c, OFFSET_CLOCK_DIV), + mtk_i2c_readw(i2c, OFFSET_FIFO_STAT)); + dev_dbg(i2c->dev, "DEBUGCTRL : 0x%x, DEBUGSTAT: 0x%x\n", + mtk_i2c_readw(i2c, OFFSET_DEBUGCTRL), + mtk_i2c_readw(i2c, OFFSET_DEBUGSTAT)); + if (i2c->dev_comp->regs == mt_i2c_regs_v2) { + dev_dbg(i2c->dev, "LTIMING: 0x%x, MULTI_DMA: 0x%x\n", + mtk_i2c_readw(i2c, OFFSET_LTIMING), + mtk_i2c_readw(i2c, OFFSET_MULTI_DMA)); + } + dev_dbg(i2c->dev, "\nDMA_INT_FLAG: 0x%x, DMA_INT_EN: 0x%x\n", + readl(i2c->pdmabase + OFFSET_INT_FLAG), + readl(i2c->pdmabase + OFFSET_INT_EN)); + dev_dbg(i2c->dev, "DMA_EN: 0x%x, DMA_CON: 0x%x\n", + readl(i2c->pdmabase + OFFSET_EN), + readl(i2c->pdmabase + OFFSET_CON)); + dev_dbg(i2c->dev, "DMA_TX_MEM_ADDR: 0x%x, DMA_RX_MEM_ADDR: 0x%x\n", + readl(i2c->pdmabase + OFFSET_TX_MEM_ADDR), + readl(i2c->pdmabase + OFFSET_RX_MEM_ADDR)); + dev_dbg(i2c->dev, "DMA_TX_LEN: 0x%x, DMA_RX_LEN: 0x%x\n", + readl(i2c->pdmabase + OFFSET_TX_LEN), + readl(i2c->pdmabase + OFFSET_RX_LEN)); + dev_dbg(i2c->dev, "DMA_TX_4G_MODE: 0x%x, DMA_RX_4G_MODE: 0x%x", + readl(i2c->pdmabase + OFFSET_TX_4G_MODE), + readl(i2c->pdmabase + OFFSET_RX_4G_MODE)); +} + +static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, + int num, int left_num) +{ + u16 addr_reg; + u16 start_reg; + u16 control_reg; + u16 restart_flag = 0; + u16 dma_sync = 0; + u32 reg_4g_mode; + u32 reg_dma_reset; + u8 *dma_rd_buf = NULL; + u8 *dma_wr_buf = NULL; + dma_addr_t rpaddr = 0; + dma_addr_t wpaddr = 0; + int ret; + + i2c->irq_stat = 0; + + if (i2c->auto_restart) + restart_flag = I2C_RS_TRANSFER; + + reinit_completion(&i2c->msg_complete); + + if (i2c->dev_comp->apdma_sync && + i2c->op != I2C_MASTER_WRRD && num > 1) { + mtk_i2c_writew(i2c, 0x00, OFFSET_DEBUGCTRL); + writel(I2C_DMA_HANDSHAKE_RST | I2C_DMA_WARM_RST, + i2c->pdmabase + OFFSET_RST); + + ret = readw_poll_timeout(i2c->pdmabase + OFFSET_RST, + reg_dma_reset, + !(reg_dma_reset & I2C_DMA_WARM_RST), + 0, 100); + if (ret) { + dev_err(i2c->dev, "DMA warm reset timeout\n"); + return -ETIMEDOUT; + } + + writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); + mtk_i2c_writew(i2c, I2C_HANDSHAKE_RST, OFFSET_SOFTRESET); + mtk_i2c_writew(i2c, I2C_CHN_CLR_FLAG, OFFSET_SOFTRESET); + mtk_i2c_writew(i2c, I2C_RELIABILITY | I2C_DMAACK_ENABLE, + OFFSET_DEBUGCTRL); + } + + control_reg = mtk_i2c_readw(i2c, OFFSET_CONTROL) & + ~(I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS); + if ((i2c->speed_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) || (left_num >= 1)) + control_reg |= I2C_CONTROL_RS; + + if (i2c->op == I2C_MASTER_WRRD) + control_reg |= I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS; + + mtk_i2c_writew(i2c, control_reg, OFFSET_CONTROL); + + addr_reg = i2c_8bit_addr_from_msg(msgs); + mtk_i2c_writew(i2c, addr_reg, OFFSET_SLAVE_ADDR); + + /* Clear interrupt status */ + mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR | + I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_STAT); + + mtk_i2c_writew(i2c, I2C_FIFO_ADDR_CLR, OFFSET_FIFO_ADDR_CLR); + + /* Enable interrupt */ + mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR | + I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_MASK); + + /* Set transfer and transaction len */ + if (i2c->op == I2C_MASTER_WRRD) { + if (i2c->dev_comp->aux_len_reg) { + mtk_i2c_writew(i2c, msgs->len, OFFSET_TRANSFER_LEN); + mtk_i2c_writew(i2c, (msgs + 1)->len, + OFFSET_TRANSFER_LEN_AUX); + } else { + mtk_i2c_writew(i2c, msgs->len | ((msgs + 1)->len) << 8, + OFFSET_TRANSFER_LEN); + } + mtk_i2c_writew(i2c, I2C_WRRD_TRANAC_VALUE, OFFSET_TRANSAC_LEN); + } else { + mtk_i2c_writew(i2c, msgs->len, OFFSET_TRANSFER_LEN); + mtk_i2c_writew(i2c, num, OFFSET_TRANSAC_LEN); + } + + if (i2c->dev_comp->apdma_sync) { + dma_sync = I2C_DMA_SKIP_CONFIG | I2C_DMA_ASYNC_MODE; + if (i2c->op == I2C_MASTER_WRRD) + dma_sync |= I2C_DMA_DIR_CHANGE; + } + + /* Prepare buffer data to start transfer */ + if (i2c->op == I2C_MASTER_RD) { + writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG); + writel(I2C_DMA_CON_RX | dma_sync, i2c->pdmabase + OFFSET_CON); + + dma_rd_buf = i2c_get_dma_safe_msg_buf(msgs, 1); + if (!dma_rd_buf) + return -ENOMEM; + + rpaddr = dma_map_single(i2c->dev, dma_rd_buf, + msgs->len, DMA_FROM_DEVICE); + if (dma_mapping_error(i2c->dev, rpaddr)) { + i2c_put_dma_safe_msg_buf(dma_rd_buf, msgs, false); + + return -ENOMEM; + } + + if (i2c->dev_comp->max_dma_support > 32) { + reg_4g_mode = upper_32_bits(rpaddr); + writel(reg_4g_mode, i2c->pdmabase + OFFSET_RX_4G_MODE); + } + + writel((u32)rpaddr, i2c->pdmabase + OFFSET_RX_MEM_ADDR); + writel(msgs->len, i2c->pdmabase + OFFSET_RX_LEN); + } else if (i2c->op == I2C_MASTER_WR) { + writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG); + writel(I2C_DMA_CON_TX | dma_sync, i2c->pdmabase + OFFSET_CON); + + dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 1); + if (!dma_wr_buf) + return -ENOMEM; + + wpaddr = dma_map_single(i2c->dev, dma_wr_buf, + msgs->len, DMA_TO_DEVICE); + if (dma_mapping_error(i2c->dev, wpaddr)) { + i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false); + + return -ENOMEM; + } + + if (i2c->dev_comp->max_dma_support > 32) { + reg_4g_mode = upper_32_bits(wpaddr); + writel(reg_4g_mode, i2c->pdmabase + OFFSET_TX_4G_MODE); + } + + writel((u32)wpaddr, i2c->pdmabase + OFFSET_TX_MEM_ADDR); + writel(msgs->len, i2c->pdmabase + OFFSET_TX_LEN); + } else { + writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_INT_FLAG); + writel(I2C_DMA_CLR_FLAG | dma_sync, i2c->pdmabase + OFFSET_CON); + + dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 1); + if (!dma_wr_buf) + return -ENOMEM; + + wpaddr = dma_map_single(i2c->dev, dma_wr_buf, + msgs->len, DMA_TO_DEVICE); + if (dma_mapping_error(i2c->dev, wpaddr)) { + i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false); + + return -ENOMEM; + } + + dma_rd_buf = i2c_get_dma_safe_msg_buf((msgs + 1), 1); + if (!dma_rd_buf) { + dma_unmap_single(i2c->dev, wpaddr, + msgs->len, DMA_TO_DEVICE); + + i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false); + + return -ENOMEM; + } + + rpaddr = dma_map_single(i2c->dev, dma_rd_buf, + (msgs + 1)->len, + DMA_FROM_DEVICE); + if (dma_mapping_error(i2c->dev, rpaddr)) { + dma_unmap_single(i2c->dev, wpaddr, + msgs->len, DMA_TO_DEVICE); + + i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false); + i2c_put_dma_safe_msg_buf(dma_rd_buf, (msgs + 1), false); + + return -ENOMEM; + } + + if (i2c->dev_comp->max_dma_support > 32) { + reg_4g_mode = upper_32_bits(wpaddr); + writel(reg_4g_mode, i2c->pdmabase + OFFSET_TX_4G_MODE); + + reg_4g_mode = upper_32_bits(rpaddr); + writel(reg_4g_mode, i2c->pdmabase + OFFSET_RX_4G_MODE); + } + + writel((u32)wpaddr, i2c->pdmabase + OFFSET_TX_MEM_ADDR); + writel((u32)rpaddr, i2c->pdmabase + OFFSET_RX_MEM_ADDR); + writel(msgs->len, i2c->pdmabase + OFFSET_TX_LEN); + writel((msgs + 1)->len, i2c->pdmabase + OFFSET_RX_LEN); + } + + writel(I2C_DMA_START_EN, i2c->pdmabase + OFFSET_EN); + + if (!i2c->auto_restart) { + start_reg = I2C_TRANSAC_START; + } else { + start_reg = I2C_TRANSAC_START | I2C_RS_MUL_TRIG; + if (left_num >= 1) + start_reg |= I2C_RS_MUL_CNFG; + } + mtk_i2c_writew(i2c, start_reg, OFFSET_START); + + ret = wait_for_completion_timeout(&i2c->msg_complete, + i2c->adap.timeout); + + /* Clear interrupt mask */ + mtk_i2c_writew(i2c, ~(restart_flag | I2C_HS_NACKERR | I2C_ACKERR | + I2C_ARB_LOST | I2C_TRANSAC_COMP), OFFSET_INTR_MASK); + + if (i2c->op == I2C_MASTER_WR) { + dma_unmap_single(i2c->dev, wpaddr, + msgs->len, DMA_TO_DEVICE); + + i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, true); + } else if (i2c->op == I2C_MASTER_RD) { + dma_unmap_single(i2c->dev, rpaddr, + msgs->len, DMA_FROM_DEVICE); + + i2c_put_dma_safe_msg_buf(dma_rd_buf, msgs, true); + } else { + dma_unmap_single(i2c->dev, wpaddr, msgs->len, + DMA_TO_DEVICE); + dma_unmap_single(i2c->dev, rpaddr, (msgs + 1)->len, + DMA_FROM_DEVICE); + + i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, true); + i2c_put_dma_safe_msg_buf(dma_rd_buf, (msgs + 1), true); + } + + if (ret == 0) { + dev_dbg(i2c->dev, "addr: %x, transfer timeout\n", msgs->addr); + i2c_dump_register(i2c); + mtk_i2c_init_hw(i2c); + return -ETIMEDOUT; + } + + if (i2c->irq_stat & (I2C_HS_NACKERR | I2C_ACKERR)) { + dev_dbg(i2c->dev, "addr: %x, transfer ACK error\n", msgs->addr); + mtk_i2c_init_hw(i2c); + return -ENXIO; + } + + return 0; +} + +static int mtk_i2c_transfer(struct i2c_adapter *adap, + struct i2c_msg msgs[], int num) +{ + int ret; + int left_num = num; + struct mtk_i2c *i2c = i2c_get_adapdata(adap); + + ret = clk_bulk_enable(I2C_MT65XX_CLK_MAX, i2c->clocks); + if (ret) + return ret; + + i2c->auto_restart = i2c->dev_comp->auto_restart; + + /* checking if we can skip restart and optimize using WRRD mode */ + if (i2c->auto_restart && num == 2) { + if (!(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD) && + msgs[0].addr == msgs[1].addr) { + i2c->auto_restart = 0; + } + } + + if (i2c->auto_restart && num >= 2 && + i2c->speed_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) + /* ignore the first restart irq after the master code, + * otherwise the first transfer will be discarded. + */ + i2c->ignore_restart_irq = true; + else + i2c->ignore_restart_irq = false; + + while (left_num--) { + if (!msgs->buf) { + dev_dbg(i2c->dev, "data buffer is NULL.\n"); + ret = -EINVAL; + goto err_exit; + } + + if (msgs->flags & I2C_M_RD) + i2c->op = I2C_MASTER_RD; + else + i2c->op = I2C_MASTER_WR; + + if (!i2c->auto_restart) { + if (num > 1) { + /* combined two messages into one transaction */ + i2c->op = I2C_MASTER_WRRD; + left_num--; + } + } + + /* always use DMA mode. */ + ret = mtk_i2c_do_transfer(i2c, msgs, num, left_num); + if (ret < 0) + goto err_exit; + + msgs++; + } + /* the return value is number of executed messages */ + ret = num; + +err_exit: + clk_bulk_disable(I2C_MT65XX_CLK_MAX, i2c->clocks); + return ret; +} + +static irqreturn_t mtk_i2c_irq(int irqno, void *dev_id) +{ + struct mtk_i2c *i2c = dev_id; + u16 restart_flag = 0; + u16 intr_stat; + + if (i2c->auto_restart) + restart_flag = I2C_RS_TRANSFER; + + intr_stat = mtk_i2c_readw(i2c, OFFSET_INTR_STAT); + mtk_i2c_writew(i2c, intr_stat, OFFSET_INTR_STAT); + + /* + * when occurs ack error, i2c controller generate two interrupts + * first is the ack error interrupt, then the complete interrupt + * i2c->irq_stat need keep the two interrupt value. + */ + i2c->irq_stat |= intr_stat; + + if (i2c->ignore_restart_irq && (i2c->irq_stat & restart_flag)) { + i2c->ignore_restart_irq = false; + i2c->irq_stat = 0; + mtk_i2c_writew(i2c, I2C_RS_MUL_CNFG | I2C_RS_MUL_TRIG | + I2C_TRANSAC_START, OFFSET_START); + } else { + if (i2c->irq_stat & (I2C_TRANSAC_COMP | restart_flag)) + complete(&i2c->msg_complete); + } + + return IRQ_HANDLED; +} + +static u32 mtk_i2c_functionality(struct i2c_adapter *adap) +{ + if (i2c_check_quirks(adap, I2C_AQ_NO_ZERO_LEN)) + return I2C_FUNC_I2C | + (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); + else + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm mtk_i2c_algorithm = { + .master_xfer = mtk_i2c_transfer, + .functionality = mtk_i2c_functionality, +}; + +static int mtk_i2c_parse_dt(struct device_node *np, struct mtk_i2c *i2c) +{ + int ret; + + ret = of_property_read_u32(np, "clock-frequency", &i2c->speed_hz); + if (ret < 0) + i2c->speed_hz = I2C_MAX_STANDARD_MODE_FREQ; + + ret = of_property_read_u32(np, "clock-div", &i2c->clk_src_div); + if (ret < 0) + return ret; + + if (i2c->clk_src_div == 0) + return -EINVAL; + + i2c->have_pmic = of_property_read_bool(np, "mediatek,have-pmic"); + i2c->use_push_pull = + of_property_read_bool(np, "mediatek,use-push-pull"); + + i2c_parse_fw_timings(i2c->dev, &i2c->timing_info, true); + + return 0; +} + +static int mtk_i2c_probe(struct platform_device *pdev) +{ + int ret = 0; + struct mtk_i2c *i2c; + int i, irq, speed_clk; + + i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(i2c->base)) + return PTR_ERR(i2c->base); + + i2c->pdmabase = devm_platform_get_and_ioremap_resource(pdev, 1, NULL); + if (IS_ERR(i2c->pdmabase)) + return PTR_ERR(i2c->pdmabase); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + init_completion(&i2c->msg_complete); + + i2c->dev_comp = of_device_get_match_data(&pdev->dev); + i2c->adap.dev.of_node = pdev->dev.of_node; + i2c->dev = &pdev->dev; + i2c->adap.dev.parent = &pdev->dev; + i2c->adap.owner = THIS_MODULE; + i2c->adap.algo = &mtk_i2c_algorithm; + i2c->adap.quirks = i2c->dev_comp->quirks; + i2c->adap.timeout = 2 * HZ; + i2c->adap.retries = 1; + i2c->adap.bus_regulator = devm_regulator_get_optional(&pdev->dev, "vbus"); + if (IS_ERR(i2c->adap.bus_regulator)) { + if (PTR_ERR(i2c->adap.bus_regulator) == -ENODEV) + i2c->adap.bus_regulator = NULL; + else + return PTR_ERR(i2c->adap.bus_regulator); + } + + ret = mtk_i2c_parse_dt(pdev->dev.of_node, i2c); + if (ret) + return -EINVAL; + + if (i2c->have_pmic && !i2c->dev_comp->pmic_i2c) + return -EINVAL; + + /* Fill in clk-bulk IDs */ + for (i = 0; i < I2C_MT65XX_CLK_MAX; i++) + i2c->clocks[i].id = i2c_mt65xx_clk_ids[i]; + + /* Get clocks one by one, some may be optional */ + i2c->clocks[I2C_MT65XX_CLK_MAIN].clk = devm_clk_get(&pdev->dev, "main"); + if (IS_ERR(i2c->clocks[I2C_MT65XX_CLK_MAIN].clk)) { + dev_err(&pdev->dev, "cannot get main clock\n"); + return PTR_ERR(i2c->clocks[I2C_MT65XX_CLK_MAIN].clk); + } + + i2c->clocks[I2C_MT65XX_CLK_DMA].clk = devm_clk_get(&pdev->dev, "dma"); + if (IS_ERR(i2c->clocks[I2C_MT65XX_CLK_DMA].clk)) { + dev_err(&pdev->dev, "cannot get dma clock\n"); + return PTR_ERR(i2c->clocks[I2C_MT65XX_CLK_DMA].clk); + } + + i2c->clocks[I2C_MT65XX_CLK_ARB].clk = devm_clk_get_optional(&pdev->dev, "arb"); + if (IS_ERR(i2c->clocks[I2C_MT65XX_CLK_ARB].clk)) + return PTR_ERR(i2c->clocks[I2C_MT65XX_CLK_ARB].clk); + + if (i2c->have_pmic) { + i2c->clocks[I2C_MT65XX_CLK_PMIC].clk = devm_clk_get(&pdev->dev, "pmic"); + if (IS_ERR(i2c->clocks[I2C_MT65XX_CLK_PMIC].clk)) { + dev_err(&pdev->dev, "cannot get pmic clock\n"); + return PTR_ERR(i2c->clocks[I2C_MT65XX_CLK_PMIC].clk); + } + speed_clk = I2C_MT65XX_CLK_PMIC; + } else { + i2c->clocks[I2C_MT65XX_CLK_PMIC].clk = NULL; + speed_clk = I2C_MT65XX_CLK_MAIN; + } + + strscpy(i2c->adap.name, I2C_DRV_NAME, sizeof(i2c->adap.name)); + + ret = mtk_i2c_set_speed(i2c, clk_get_rate(i2c->clocks[speed_clk].clk)); + if (ret) { + dev_err(&pdev->dev, "Failed to set the speed.\n"); + return -EINVAL; + } + + if (i2c->dev_comp->max_dma_support > 32) { + ret = dma_set_mask(&pdev->dev, + DMA_BIT_MASK(i2c->dev_comp->max_dma_support)); + if (ret) { + dev_err(&pdev->dev, "dma_set_mask return error.\n"); + return ret; + } + } + + ret = clk_bulk_prepare_enable(I2C_MT65XX_CLK_MAX, i2c->clocks); + if (ret) { + dev_err(&pdev->dev, "clock enable failed!\n"); + return ret; + } + mtk_i2c_init_hw(i2c); + clk_bulk_disable(I2C_MT65XX_CLK_MAX, i2c->clocks); + + ret = devm_request_irq(&pdev->dev, irq, mtk_i2c_irq, + IRQF_NO_SUSPEND | IRQF_TRIGGER_NONE, + dev_name(&pdev->dev), i2c); + if (ret < 0) { + dev_err(&pdev->dev, + "Request I2C IRQ %d fail\n", irq); + goto err_bulk_unprepare; + } + + i2c_set_adapdata(&i2c->adap, i2c); + ret = i2c_add_adapter(&i2c->adap); + if (ret) + goto err_bulk_unprepare; + + platform_set_drvdata(pdev, i2c); + + return 0; + +err_bulk_unprepare: + clk_bulk_unprepare(I2C_MT65XX_CLK_MAX, i2c->clocks); + + return ret; +} + +static void mtk_i2c_remove(struct platform_device *pdev) +{ + struct mtk_i2c *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adap); + + clk_bulk_unprepare(I2C_MT65XX_CLK_MAX, i2c->clocks); +} + +static int mtk_i2c_suspend_noirq(struct device *dev) +{ + struct mtk_i2c *i2c = dev_get_drvdata(dev); + + i2c_mark_adapter_suspended(&i2c->adap); + clk_bulk_unprepare(I2C_MT65XX_CLK_MAX, i2c->clocks); + + return 0; +} + +static int mtk_i2c_resume_noirq(struct device *dev) +{ + int ret; + struct mtk_i2c *i2c = dev_get_drvdata(dev); + + ret = clk_bulk_prepare_enable(I2C_MT65XX_CLK_MAX, i2c->clocks); + if (ret) { + dev_err(dev, "clock enable failed!\n"); + return ret; + } + + mtk_i2c_init_hw(i2c); + + clk_bulk_disable(I2C_MT65XX_CLK_MAX, i2c->clocks); + + i2c_mark_adapter_resumed(&i2c->adap); + + return 0; +} + +static const struct dev_pm_ops mtk_i2c_pm = { + NOIRQ_SYSTEM_SLEEP_PM_OPS(mtk_i2c_suspend_noirq, + mtk_i2c_resume_noirq) +}; + +static struct platform_driver mtk_i2c_driver = { + .probe = mtk_i2c_probe, + .remove_new = mtk_i2c_remove, + .driver = { + .name = I2C_DRV_NAME, + .pm = pm_sleep_ptr(&mtk_i2c_pm), + .of_match_table = mtk_i2c_of_match, + }, +}; + +module_platform_driver(mtk_i2c_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("MediaTek I2C Bus Driver"); +MODULE_AUTHOR("Xudong Chen <xudong.chen@mediatek.com>"); diff --git a/drivers/i2c/busses/i2c-mt7621.c b/drivers/i2c/busses/i2c-mt7621.c new file mode 100644 index 000000000..81d46169b --- /dev/null +++ b/drivers/i2c/busses/i2c-mt7621.c @@ -0,0 +1,346 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * drivers/i2c/busses/i2c-mt7621.c + * + * Copyright (C) 2013 Steven Liu <steven_liu@mediatek.com> + * Copyright (C) 2016 Michael Lee <igvtee@gmail.com> + * Copyright (C) 2018 Jan Breuer <jan.breuer@jaybee.cz> + * + * Improve driver for i2cdetect from i2c-tools to detect i2c devices on the bus. + * (C) 2014 Sittisak <sittisaks@hotmail.com> + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reset.h> + +#define REG_SM0CFG2_REG 0x28 +#define REG_SM0CTL0_REG 0x40 +#define REG_SM0CTL1_REG 0x44 +#define REG_SM0D0_REG 0x50 +#define REG_SM0D1_REG 0x54 +#define REG_PINTEN_REG 0x5c +#define REG_PINTST_REG 0x60 +#define REG_PINTCL_REG 0x64 + +/* REG_SM0CFG2_REG */ +#define SM0CFG2_IS_AUTOMODE BIT(0) + +/* REG_SM0CTL0_REG */ +#define SM0CTL0_ODRAIN BIT(31) +#define SM0CTL0_CLK_DIV_MASK (0x7ff << 16) +#define SM0CTL0_CLK_DIV_MAX 0x7ff +#define SM0CTL0_CS_STATUS BIT(4) +#define SM0CTL0_SCL_STATE BIT(3) +#define SM0CTL0_SDA_STATE BIT(2) +#define SM0CTL0_EN BIT(1) +#define SM0CTL0_SCL_STRETCH BIT(0) + +/* REG_SM0CTL1_REG */ +#define SM0CTL1_ACK_MASK (0xff << 16) +#define SM0CTL1_PGLEN_MASK (0x7 << 8) +#define SM0CTL1_PGLEN(x) ((((x) - 1) << 8) & SM0CTL1_PGLEN_MASK) +#define SM0CTL1_READ (5 << 4) +#define SM0CTL1_READ_LAST (4 << 4) +#define SM0CTL1_STOP (3 << 4) +#define SM0CTL1_WRITE (2 << 4) +#define SM0CTL1_START (1 << 4) +#define SM0CTL1_MODE_MASK (0x7 << 4) +#define SM0CTL1_TRI BIT(0) + +/* timeout waiting for I2C devices to respond */ +#define TIMEOUT_MS 1000 + +struct mtk_i2c { + void __iomem *base; + struct device *dev; + struct i2c_adapter adap; + u32 bus_freq; + u32 clk_div; + u32 flags; + struct clk *clk; +}; + +static int mtk_i2c_wait_idle(struct mtk_i2c *i2c) +{ + int ret; + u32 val; + + ret = readl_relaxed_poll_timeout(i2c->base + REG_SM0CTL1_REG, + val, !(val & SM0CTL1_TRI), + 10, TIMEOUT_MS * 1000); + if (ret) + dev_dbg(i2c->dev, "idle err(%d)\n", ret); + + return ret; +} + +static void mtk_i2c_reset(struct mtk_i2c *i2c) +{ + int ret; + + ret = device_reset(i2c->adap.dev.parent); + if (ret) + dev_err(i2c->dev, "I2C reset failed!\n"); + + /* + * Don't set SM0CTL0_ODRAIN as its bit meaning is inverted. To + * configure open-drain mode, this bit needs to be cleared. + */ + iowrite32(((i2c->clk_div << 16) & SM0CTL0_CLK_DIV_MASK) | SM0CTL0_EN | + SM0CTL0_SCL_STRETCH, i2c->base + REG_SM0CTL0_REG); + iowrite32(0, i2c->base + REG_SM0CFG2_REG); +} + +static void mtk_i2c_dump_reg(struct mtk_i2c *i2c) +{ + dev_dbg(i2c->dev, + "SM0CFG2 %08x, SM0CTL0 %08x, SM0CTL1 %08x, SM0D0 %08x, SM0D1 %08x\n", + ioread32(i2c->base + REG_SM0CFG2_REG), + ioread32(i2c->base + REG_SM0CTL0_REG), + ioread32(i2c->base + REG_SM0CTL1_REG), + ioread32(i2c->base + REG_SM0D0_REG), + ioread32(i2c->base + REG_SM0D1_REG)); +} + +static int mtk_i2c_check_ack(struct mtk_i2c *i2c, u32 expected) +{ + u32 ack = readl_relaxed(i2c->base + REG_SM0CTL1_REG); + u32 ack_expected = (expected << 16) & SM0CTL1_ACK_MASK; + + return ((ack & ack_expected) == ack_expected) ? 0 : -ENXIO; +} + +static int mtk_i2c_master_start(struct mtk_i2c *i2c) +{ + iowrite32(SM0CTL1_START | SM0CTL1_TRI, i2c->base + REG_SM0CTL1_REG); + return mtk_i2c_wait_idle(i2c); +} + +static int mtk_i2c_master_stop(struct mtk_i2c *i2c) +{ + iowrite32(SM0CTL1_STOP | SM0CTL1_TRI, i2c->base + REG_SM0CTL1_REG); + return mtk_i2c_wait_idle(i2c); +} + +static int mtk_i2c_master_cmd(struct mtk_i2c *i2c, u32 cmd, int page_len) +{ + iowrite32(cmd | SM0CTL1_TRI | SM0CTL1_PGLEN(page_len), + i2c->base + REG_SM0CTL1_REG); + return mtk_i2c_wait_idle(i2c); +} + +static int mtk_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct mtk_i2c *i2c; + struct i2c_msg *pmsg; + u16 addr; + int i, j, ret, len, page_len; + u32 cmd; + u32 data[2]; + + i2c = i2c_get_adapdata(adap); + + for (i = 0; i < num; i++) { + pmsg = &msgs[i]; + + /* wait hardware idle */ + ret = mtk_i2c_wait_idle(i2c); + if (ret) + goto err_timeout; + + /* start sequence */ + ret = mtk_i2c_master_start(i2c); + if (ret) + goto err_timeout; + + /* write address */ + if (pmsg->flags & I2C_M_TEN) { + /* 10 bits address */ + addr = 0xf0 | ((pmsg->addr >> 7) & 0x06); + addr |= (pmsg->addr & 0xff) << 8; + if (pmsg->flags & I2C_M_RD) + addr |= 1; + iowrite32(addr, i2c->base + REG_SM0D0_REG); + ret = mtk_i2c_master_cmd(i2c, SM0CTL1_WRITE, 2); + if (ret) + goto err_timeout; + } else { + /* 7 bits address */ + addr = i2c_8bit_addr_from_msg(pmsg); + iowrite32(addr, i2c->base + REG_SM0D0_REG); + ret = mtk_i2c_master_cmd(i2c, SM0CTL1_WRITE, 1); + if (ret) + goto err_timeout; + } + + /* check address ACK */ + if (!(pmsg->flags & I2C_M_IGNORE_NAK)) { + ret = mtk_i2c_check_ack(i2c, BIT(0)); + if (ret) + goto err_ack; + } + + /* transfer data */ + for (len = pmsg->len, j = 0; len > 0; len -= 8, j += 8) { + page_len = (len >= 8) ? 8 : len; + + if (pmsg->flags & I2C_M_RD) { + cmd = (len > 8) ? + SM0CTL1_READ : SM0CTL1_READ_LAST; + } else { + memcpy(data, &pmsg->buf[j], page_len); + iowrite32(data[0], i2c->base + REG_SM0D0_REG); + iowrite32(data[1], i2c->base + REG_SM0D1_REG); + cmd = SM0CTL1_WRITE; + } + + ret = mtk_i2c_master_cmd(i2c, cmd, page_len); + if (ret) + goto err_timeout; + + if (pmsg->flags & I2C_M_RD) { + data[0] = ioread32(i2c->base + REG_SM0D0_REG); + data[1] = ioread32(i2c->base + REG_SM0D1_REG); + memcpy(&pmsg->buf[j], data, page_len); + } else { + if (!(pmsg->flags & I2C_M_IGNORE_NAK)) { + ret = mtk_i2c_check_ack(i2c, + (1 << page_len) + - 1); + if (ret) + goto err_ack; + } + } + } + } + + ret = mtk_i2c_master_stop(i2c); + if (ret) + goto err_timeout; + + /* the return value is number of executed messages */ + return i; + +err_ack: + ret = mtk_i2c_master_stop(i2c); + if (ret) + goto err_timeout; + return -ENXIO; + +err_timeout: + mtk_i2c_dump_reg(i2c); + mtk_i2c_reset(i2c); + return ret; +} + +static u32 mtk_i2c_func(struct i2c_adapter *a) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_PROTOCOL_MANGLING; +} + +static const struct i2c_algorithm mtk_i2c_algo = { + .master_xfer = mtk_i2c_master_xfer, + .functionality = mtk_i2c_func, +}; + +static const struct of_device_id i2c_mtk_dt_ids[] = { + { .compatible = "mediatek,mt7621-i2c" }, + { /* sentinel */ } +}; + +MODULE_DEVICE_TABLE(of, i2c_mtk_dt_ids); + +static void mtk_i2c_init(struct mtk_i2c *i2c) +{ + i2c->clk_div = clk_get_rate(i2c->clk) / i2c->bus_freq - 1; + if (i2c->clk_div < 99) + i2c->clk_div = 99; + if (i2c->clk_div > SM0CTL0_CLK_DIV_MAX) + i2c->clk_div = SM0CTL0_CLK_DIV_MAX; + + mtk_i2c_reset(i2c); +} + +static int mtk_i2c_probe(struct platform_device *pdev) +{ + struct mtk_i2c *i2c; + struct i2c_adapter *adap; + int ret; + + i2c = devm_kzalloc(&pdev->dev, sizeof(struct mtk_i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(i2c->base)) + return PTR_ERR(i2c->base); + + i2c->clk = devm_clk_get_enabled(&pdev->dev, NULL); + if (IS_ERR(i2c->clk)) { + dev_err(&pdev->dev, "Failed to enable clock\n"); + return PTR_ERR(i2c->clk); + } + + i2c->dev = &pdev->dev; + + if (of_property_read_u32(pdev->dev.of_node, "clock-frequency", + &i2c->bus_freq)) + i2c->bus_freq = I2C_MAX_STANDARD_MODE_FREQ; + + if (i2c->bus_freq == 0) { + dev_warn(i2c->dev, "clock-frequency 0 not supported\n"); + return -EINVAL; + } + + adap = &i2c->adap; + adap->owner = THIS_MODULE; + adap->algo = &mtk_i2c_algo; + adap->retries = 3; + adap->dev.parent = &pdev->dev; + i2c_set_adapdata(adap, i2c); + adap->dev.of_node = pdev->dev.of_node; + strscpy(adap->name, dev_name(&pdev->dev), sizeof(adap->name)); + + platform_set_drvdata(pdev, i2c); + + mtk_i2c_init(i2c); + + ret = i2c_add_adapter(adap); + if (ret < 0) + return ret; + + dev_info(&pdev->dev, "clock %u kHz\n", i2c->bus_freq / 1000); + + return 0; +} + +static void mtk_i2c_remove(struct platform_device *pdev) +{ + struct mtk_i2c *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adap); +} + +static struct platform_driver mtk_i2c_driver = { + .probe = mtk_i2c_probe, + .remove_new = mtk_i2c_remove, + .driver = { + .name = "i2c-mt7621", + .of_match_table = i2c_mtk_dt_ids, + }, +}; + +module_platform_driver(mtk_i2c_driver); + +MODULE_AUTHOR("Steven Liu"); +MODULE_DESCRIPTION("MT7621 I2C host driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:MT7621-I2C"); diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c new file mode 100644 index 000000000..fd8403b07 --- /dev/null +++ b/drivers/i2c/busses/i2c-mv64xxx.c @@ -0,0 +1,1120 @@ +/* + * Driver for the i2c controller on the Marvell line of host bridges + * (e.g, gt642[46]0, mv643[46]0, mv644[46]0, and Orion SoC family). + * + * Author: Mark A. Greer <mgreer@mvista.com> + * + * 2005 (c) MontaVista, Software, Inc. This file is licensed under + * the terms of the GNU General Public License version 2. This program + * is licensed "as is" without any warranty of any kind, whether express + * or implied. + */ +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/spinlock.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/mv643xx_i2c.h> +#include <linux/platform_device.h> +#include <linux/pinctrl/consumer.h> +#include <linux/pm_runtime.h> +#include <linux/reset.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_irq.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/delay.h> + +#define MV64XXX_I2C_ADDR_ADDR(val) ((val & 0x7f) << 1) +#define MV64XXX_I2C_BAUD_DIV_N(val) (val & 0x7) +#define MV64XXX_I2C_BAUD_DIV_M(val) ((val & 0xf) << 3) + +#define MV64XXX_I2C_REG_CONTROL_ACK BIT(2) +#define MV64XXX_I2C_REG_CONTROL_IFLG BIT(3) +#define MV64XXX_I2C_REG_CONTROL_STOP BIT(4) +#define MV64XXX_I2C_REG_CONTROL_START BIT(5) +#define MV64XXX_I2C_REG_CONTROL_TWSIEN BIT(6) +#define MV64XXX_I2C_REG_CONTROL_INTEN BIT(7) + +/* Ctlr status values */ +#define MV64XXX_I2C_STATUS_BUS_ERR 0x00 +#define MV64XXX_I2C_STATUS_MAST_START 0x08 +#define MV64XXX_I2C_STATUS_MAST_REPEAT_START 0x10 +#define MV64XXX_I2C_STATUS_MAST_WR_ADDR_ACK 0x18 +#define MV64XXX_I2C_STATUS_MAST_WR_ADDR_NO_ACK 0x20 +#define MV64XXX_I2C_STATUS_MAST_WR_ACK 0x28 +#define MV64XXX_I2C_STATUS_MAST_WR_NO_ACK 0x30 +#define MV64XXX_I2C_STATUS_MAST_LOST_ARB 0x38 +#define MV64XXX_I2C_STATUS_MAST_RD_ADDR_ACK 0x40 +#define MV64XXX_I2C_STATUS_MAST_RD_ADDR_NO_ACK 0x48 +#define MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK 0x50 +#define MV64XXX_I2C_STATUS_MAST_RD_DATA_NO_ACK 0x58 +#define MV64XXX_I2C_STATUS_MAST_WR_ADDR_2_ACK 0xd0 +#define MV64XXX_I2C_STATUS_MAST_WR_ADDR_2_NO_ACK 0xd8 +#define MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_ACK 0xe0 +#define MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_NO_ACK 0xe8 +#define MV64XXX_I2C_STATUS_NO_STATUS 0xf8 + +/* Register defines (I2C bridge) */ +#define MV64XXX_I2C_REG_TX_DATA_LO 0xc0 +#define MV64XXX_I2C_REG_TX_DATA_HI 0xc4 +#define MV64XXX_I2C_REG_RX_DATA_LO 0xc8 +#define MV64XXX_I2C_REG_RX_DATA_HI 0xcc +#define MV64XXX_I2C_REG_BRIDGE_CONTROL 0xd0 +#define MV64XXX_I2C_REG_BRIDGE_STATUS 0xd4 +#define MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE 0xd8 +#define MV64XXX_I2C_REG_BRIDGE_INTR_MASK 0xdC +#define MV64XXX_I2C_REG_BRIDGE_TIMING 0xe0 + +/* Bridge Control values */ +#define MV64XXX_I2C_BRIDGE_CONTROL_WR BIT(0) +#define MV64XXX_I2C_BRIDGE_CONTROL_RD BIT(1) +#define MV64XXX_I2C_BRIDGE_CONTROL_ADDR_SHIFT 2 +#define MV64XXX_I2C_BRIDGE_CONTROL_ADDR_EXT BIT(12) +#define MV64XXX_I2C_BRIDGE_CONTROL_TX_SIZE_SHIFT 13 +#define MV64XXX_I2C_BRIDGE_CONTROL_RX_SIZE_SHIFT 16 +#define MV64XXX_I2C_BRIDGE_CONTROL_ENABLE BIT(19) +#define MV64XXX_I2C_BRIDGE_CONTROL_REPEATED_START BIT(20) + +/* Bridge Status values */ +#define MV64XXX_I2C_BRIDGE_STATUS_ERROR BIT(0) + +/* Driver states */ +enum { + MV64XXX_I2C_STATE_INVALID, + MV64XXX_I2C_STATE_IDLE, + MV64XXX_I2C_STATE_WAITING_FOR_START_COND, + MV64XXX_I2C_STATE_WAITING_FOR_RESTART, + MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK, + MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK, + MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK, + MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA, +}; + +/* Driver actions */ +enum { + MV64XXX_I2C_ACTION_INVALID, + MV64XXX_I2C_ACTION_CONTINUE, + MV64XXX_I2C_ACTION_SEND_RESTART, + MV64XXX_I2C_ACTION_SEND_ADDR_1, + MV64XXX_I2C_ACTION_SEND_ADDR_2, + MV64XXX_I2C_ACTION_SEND_DATA, + MV64XXX_I2C_ACTION_RCV_DATA, + MV64XXX_I2C_ACTION_RCV_DATA_STOP, + MV64XXX_I2C_ACTION_SEND_STOP, +}; + +struct mv64xxx_i2c_regs { + u8 addr; + u8 ext_addr; + u8 data; + u8 control; + u8 status; + u8 clock; + u8 soft_reset; +}; + +struct mv64xxx_i2c_data { + struct i2c_msg *msgs; + int num_msgs; + int irq; + u32 state; + u32 action; + u32 aborting; + u32 cntl_bits; + void __iomem *reg_base; + struct mv64xxx_i2c_regs reg_offsets; + u32 addr1; + u32 addr2; + u32 bytes_left; + u32 byte_posn; + u32 send_stop; + u32 block; + int rc; + u32 freq_m; + u32 freq_n; + struct clk *clk; + struct clk *reg_clk; + wait_queue_head_t waitq; + spinlock_t lock; + struct i2c_msg *msg; + struct i2c_adapter adapter; + bool offload_enabled; +/* 5us delay in order to avoid repeated start timing violation */ + bool errata_delay; + struct reset_control *rstc; + bool irq_clear_inverted; + /* Clk div is 2 to the power n, not 2 to the power n + 1 */ + bool clk_n_base_0; + struct i2c_bus_recovery_info rinfo; + bool atomic; +}; + +static struct mv64xxx_i2c_regs mv64xxx_i2c_regs_mv64xxx = { + .addr = 0x00, + .ext_addr = 0x10, + .data = 0x04, + .control = 0x08, + .status = 0x0c, + .clock = 0x0c, + .soft_reset = 0x1c, +}; + +static struct mv64xxx_i2c_regs mv64xxx_i2c_regs_sun4i = { + .addr = 0x00, + .ext_addr = 0x04, + .data = 0x08, + .control = 0x0c, + .status = 0x10, + .clock = 0x14, + .soft_reset = 0x18, +}; + +static void +mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data *drv_data, + struct i2c_msg *msg) +{ + u32 dir = 0; + + drv_data->cntl_bits = MV64XXX_I2C_REG_CONTROL_ACK | + MV64XXX_I2C_REG_CONTROL_TWSIEN; + + if (!drv_data->atomic) + drv_data->cntl_bits |= MV64XXX_I2C_REG_CONTROL_INTEN; + + if (msg->flags & I2C_M_RD) + dir = 1; + + if (msg->flags & I2C_M_TEN) { + drv_data->addr1 = 0xf0 | (((u32)msg->addr & 0x300) >> 7) | dir; + drv_data->addr2 = (u32)msg->addr & 0xff; + } else { + drv_data->addr1 = MV64XXX_I2C_ADDR_ADDR((u32)msg->addr) | dir; + drv_data->addr2 = 0; + } +} + +/* + ***************************************************************************** + * + * Finite State Machine & Interrupt Routines + * + ***************************************************************************** + */ + +/* Reset hardware and initialize FSM */ +static void +mv64xxx_i2c_hw_init(struct mv64xxx_i2c_data *drv_data) +{ + if (drv_data->offload_enabled) { + writel(0, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_CONTROL); + writel(0, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_TIMING); + writel(0, drv_data->reg_base + + MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE); + writel(0, drv_data->reg_base + + MV64XXX_I2C_REG_BRIDGE_INTR_MASK); + } + + writel(0, drv_data->reg_base + drv_data->reg_offsets.soft_reset); + writel(MV64XXX_I2C_BAUD_DIV_M(drv_data->freq_m) | MV64XXX_I2C_BAUD_DIV_N(drv_data->freq_n), + drv_data->reg_base + drv_data->reg_offsets.clock); + writel(0, drv_data->reg_base + drv_data->reg_offsets.addr); + writel(0, drv_data->reg_base + drv_data->reg_offsets.ext_addr); + writel(MV64XXX_I2C_REG_CONTROL_TWSIEN | MV64XXX_I2C_REG_CONTROL_STOP, + drv_data->reg_base + drv_data->reg_offsets.control); + + if (drv_data->errata_delay) + udelay(5); + + drv_data->state = MV64XXX_I2C_STATE_IDLE; +} + +static void +mv64xxx_i2c_fsm(struct mv64xxx_i2c_data *drv_data, u32 status) +{ + /* + * If state is idle, then this is likely the remnants of an old + * operation that driver has given up on or the user has killed. + * If so, issue the stop condition and go to idle. + */ + if (drv_data->state == MV64XXX_I2C_STATE_IDLE) { + drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP; + return; + } + + /* The status from the ctlr [mostly] tells us what to do next */ + switch (status) { + /* Start condition interrupt */ + case MV64XXX_I2C_STATUS_MAST_START: /* 0x08 */ + case MV64XXX_I2C_STATUS_MAST_REPEAT_START: /* 0x10 */ + drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_1; + drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK; + break; + + /* Performing a write */ + case MV64XXX_I2C_STATUS_MAST_WR_ADDR_ACK: /* 0x18 */ + if (drv_data->msg->flags & I2C_M_TEN) { + drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_2; + drv_data->state = + MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK; + break; + } + fallthrough; + case MV64XXX_I2C_STATUS_MAST_WR_ADDR_2_ACK: /* 0xd0 */ + case MV64XXX_I2C_STATUS_MAST_WR_ACK: /* 0x28 */ + if ((drv_data->bytes_left == 0) + || (drv_data->aborting + && (drv_data->byte_posn != 0))) { + if (drv_data->send_stop || drv_data->aborting) { + drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP; + drv_data->state = MV64XXX_I2C_STATE_IDLE; + } else { + drv_data->action = + MV64XXX_I2C_ACTION_SEND_RESTART; + drv_data->state = + MV64XXX_I2C_STATE_WAITING_FOR_RESTART; + } + } else { + drv_data->action = MV64XXX_I2C_ACTION_SEND_DATA; + drv_data->state = + MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK; + drv_data->bytes_left--; + } + break; + + /* Performing a read */ + case MV64XXX_I2C_STATUS_MAST_RD_ADDR_ACK: /* 40 */ + if (drv_data->msg->flags & I2C_M_TEN) { + drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_2; + drv_data->state = + MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK; + break; + } + fallthrough; + case MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_ACK: /* 0xe0 */ + if (drv_data->bytes_left == 0) { + drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP; + drv_data->state = MV64XXX_I2C_STATE_IDLE; + break; + } + fallthrough; + case MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK: /* 0x50 */ + if (status != MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK) + drv_data->action = MV64XXX_I2C_ACTION_CONTINUE; + else { + drv_data->action = MV64XXX_I2C_ACTION_RCV_DATA; + drv_data->bytes_left--; + } + drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA; + + if ((drv_data->bytes_left == 1) || drv_data->aborting) + drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_ACK; + break; + + case MV64XXX_I2C_STATUS_MAST_RD_DATA_NO_ACK: /* 0x58 */ + drv_data->action = MV64XXX_I2C_ACTION_RCV_DATA_STOP; + drv_data->state = MV64XXX_I2C_STATE_IDLE; + break; + + case MV64XXX_I2C_STATUS_MAST_WR_ADDR_NO_ACK: /* 0x20 */ + case MV64XXX_I2C_STATUS_MAST_WR_NO_ACK: /* 30 */ + case MV64XXX_I2C_STATUS_MAST_RD_ADDR_NO_ACK: /* 48 */ + /* Doesn't seem to be a device at other end */ + drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP; + drv_data->state = MV64XXX_I2C_STATE_IDLE; + drv_data->rc = -ENXIO; + break; + + default: + dev_err(&drv_data->adapter.dev, + "mv64xxx_i2c_fsm: Ctlr Error -- state: 0x%x, " + "status: 0x%x, addr: 0x%x, flags: 0x%x\n", + drv_data->state, status, drv_data->msg->addr, + drv_data->msg->flags); + drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP; + mv64xxx_i2c_hw_init(drv_data); + i2c_recover_bus(&drv_data->adapter); + drv_data->rc = -EAGAIN; + } +} + +static void mv64xxx_i2c_send_start(struct mv64xxx_i2c_data *drv_data) +{ + drv_data->msg = drv_data->msgs; + drv_data->byte_posn = 0; + drv_data->bytes_left = drv_data->msg->len; + drv_data->aborting = 0; + drv_data->rc = 0; + + mv64xxx_i2c_prepare_for_io(drv_data, drv_data->msgs); + writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_START, + drv_data->reg_base + drv_data->reg_offsets.control); +} + +static void +mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data) +{ + switch(drv_data->action) { + case MV64XXX_I2C_ACTION_SEND_RESTART: + /* We should only get here if we have further messages */ + BUG_ON(drv_data->num_msgs == 0); + + drv_data->msgs++; + drv_data->num_msgs--; + mv64xxx_i2c_send_start(drv_data); + + if (drv_data->errata_delay) + udelay(5); + + /* + * We're never at the start of the message here, and by this + * time it's already too late to do any protocol mangling. + * Thankfully, do not advertise support for that feature. + */ + drv_data->send_stop = drv_data->num_msgs == 1; + break; + + case MV64XXX_I2C_ACTION_CONTINUE: + writel(drv_data->cntl_bits, + drv_data->reg_base + drv_data->reg_offsets.control); + break; + + case MV64XXX_I2C_ACTION_SEND_ADDR_1: + writel(drv_data->addr1, + drv_data->reg_base + drv_data->reg_offsets.data); + writel(drv_data->cntl_bits, + drv_data->reg_base + drv_data->reg_offsets.control); + break; + + case MV64XXX_I2C_ACTION_SEND_ADDR_2: + writel(drv_data->addr2, + drv_data->reg_base + drv_data->reg_offsets.data); + writel(drv_data->cntl_bits, + drv_data->reg_base + drv_data->reg_offsets.control); + break; + + case MV64XXX_I2C_ACTION_SEND_DATA: + writel(drv_data->msg->buf[drv_data->byte_posn++], + drv_data->reg_base + drv_data->reg_offsets.data); + writel(drv_data->cntl_bits, + drv_data->reg_base + drv_data->reg_offsets.control); + break; + + case MV64XXX_I2C_ACTION_RCV_DATA: + drv_data->msg->buf[drv_data->byte_posn++] = + readl(drv_data->reg_base + drv_data->reg_offsets.data); + writel(drv_data->cntl_bits, + drv_data->reg_base + drv_data->reg_offsets.control); + break; + + case MV64XXX_I2C_ACTION_RCV_DATA_STOP: + drv_data->msg->buf[drv_data->byte_posn++] = + readl(drv_data->reg_base + drv_data->reg_offsets.data); + if (!drv_data->atomic) + drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN; + writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP, + drv_data->reg_base + drv_data->reg_offsets.control); + drv_data->block = 0; + if (drv_data->errata_delay) + udelay(5); + + wake_up(&drv_data->waitq); + break; + + case MV64XXX_I2C_ACTION_INVALID: + default: + dev_err(&drv_data->adapter.dev, + "mv64xxx_i2c_do_action: Invalid action: %d\n", + drv_data->action); + drv_data->rc = -EIO; + fallthrough; + case MV64XXX_I2C_ACTION_SEND_STOP: + if (!drv_data->atomic) + drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN; + writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP, + drv_data->reg_base + drv_data->reg_offsets.control); + drv_data->block = 0; + wake_up(&drv_data->waitq); + break; + } +} + +static void +mv64xxx_i2c_read_offload_rx_data(struct mv64xxx_i2c_data *drv_data, + struct i2c_msg *msg) +{ + u32 buf[2]; + + buf[0] = readl(drv_data->reg_base + MV64XXX_I2C_REG_RX_DATA_LO); + buf[1] = readl(drv_data->reg_base + MV64XXX_I2C_REG_RX_DATA_HI); + + memcpy(msg->buf, buf, msg->len); +} + +static int +mv64xxx_i2c_intr_offload(struct mv64xxx_i2c_data *drv_data) +{ + u32 cause, status; + + cause = readl(drv_data->reg_base + + MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE); + if (!cause) + return IRQ_NONE; + + status = readl(drv_data->reg_base + + MV64XXX_I2C_REG_BRIDGE_STATUS); + + if (status & MV64XXX_I2C_BRIDGE_STATUS_ERROR) { + drv_data->rc = -EIO; + goto out; + } + + drv_data->rc = 0; + + /* + * Transaction is a one message read transaction, read data + * for this message. + */ + if (drv_data->num_msgs == 1 && drv_data->msgs[0].flags & I2C_M_RD) { + mv64xxx_i2c_read_offload_rx_data(drv_data, drv_data->msgs); + drv_data->msgs++; + drv_data->num_msgs--; + } + /* + * Transaction is a two messages write/read transaction, read + * data for the second (read) message. + */ + else if (drv_data->num_msgs == 2 && + !(drv_data->msgs[0].flags & I2C_M_RD) && + drv_data->msgs[1].flags & I2C_M_RD) { + mv64xxx_i2c_read_offload_rx_data(drv_data, drv_data->msgs + 1); + drv_data->msgs += 2; + drv_data->num_msgs -= 2; + } + +out: + writel(0, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_CONTROL); + writel(0, drv_data->reg_base + + MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE); + drv_data->block = 0; + + wake_up(&drv_data->waitq); + + return IRQ_HANDLED; +} + +static irqreturn_t +mv64xxx_i2c_intr(int irq, void *dev_id) +{ + struct mv64xxx_i2c_data *drv_data = dev_id; + u32 status; + irqreturn_t rc = IRQ_NONE; + + spin_lock(&drv_data->lock); + + if (drv_data->offload_enabled) + rc = mv64xxx_i2c_intr_offload(drv_data); + + while (readl(drv_data->reg_base + drv_data->reg_offsets.control) & + MV64XXX_I2C_REG_CONTROL_IFLG) { + /* + * It seems that sometime the controller updates the status + * register only after it asserts IFLG in control register. + * This may result in weird bugs when in atomic mode. A delay + * of 100 ns before reading the status register solves this + * issue. This bug does not seem to appear when using + * interrupts. + */ + if (drv_data->atomic) + ndelay(100); + + status = readl(drv_data->reg_base + drv_data->reg_offsets.status); + mv64xxx_i2c_fsm(drv_data, status); + mv64xxx_i2c_do_action(drv_data); + + if (drv_data->irq_clear_inverted) + writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_IFLG, + drv_data->reg_base + drv_data->reg_offsets.control); + + rc = IRQ_HANDLED; + } + spin_unlock(&drv_data->lock); + + return rc; +} + +/* + ***************************************************************************** + * + * I2C Msg Execution Routines + * + ***************************************************************************** + */ +static void +mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data *drv_data) +{ + long time_left; + unsigned long flags; + char abort = 0; + + time_left = wait_event_timeout(drv_data->waitq, + !drv_data->block, drv_data->adapter.timeout); + + spin_lock_irqsave(&drv_data->lock, flags); + if (!time_left) { /* Timed out */ + drv_data->rc = -ETIMEDOUT; + abort = 1; + } else if (time_left < 0) { /* Interrupted/Error */ + drv_data->rc = time_left; /* errno value */ + abort = 1; + } + + if (abort && drv_data->block) { + drv_data->aborting = 1; + spin_unlock_irqrestore(&drv_data->lock, flags); + + time_left = wait_event_timeout(drv_data->waitq, + !drv_data->block, drv_data->adapter.timeout); + + if ((time_left <= 0) && drv_data->block) { + drv_data->state = MV64XXX_I2C_STATE_IDLE; + dev_err(&drv_data->adapter.dev, + "mv64xxx: I2C bus locked, block: %d, " + "time_left: %d\n", drv_data->block, + (int)time_left); + mv64xxx_i2c_hw_init(drv_data); + i2c_recover_bus(&drv_data->adapter); + } + } else + spin_unlock_irqrestore(&drv_data->lock, flags); +} + +static void mv64xxx_i2c_wait_polling(struct mv64xxx_i2c_data *drv_data) +{ + ktime_t timeout = ktime_add_ms(ktime_get(), drv_data->adapter.timeout); + + while (READ_ONCE(drv_data->block) && + ktime_compare(ktime_get(), timeout) < 0) { + udelay(5); + mv64xxx_i2c_intr(0, drv_data); + } +} + +static int +mv64xxx_i2c_execute_msg(struct mv64xxx_i2c_data *drv_data, struct i2c_msg *msg, + int is_last) +{ + unsigned long flags; + + spin_lock_irqsave(&drv_data->lock, flags); + + drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_START_COND; + + drv_data->send_stop = is_last; + drv_data->block = 1; + mv64xxx_i2c_send_start(drv_data); + spin_unlock_irqrestore(&drv_data->lock, flags); + + if (!drv_data->atomic) + mv64xxx_i2c_wait_for_completion(drv_data); + else + mv64xxx_i2c_wait_polling(drv_data); + + return drv_data->rc; +} + +static void +mv64xxx_i2c_prepare_tx(struct mv64xxx_i2c_data *drv_data) +{ + struct i2c_msg *msg = drv_data->msgs; + u32 buf[2]; + + memcpy(buf, msg->buf, msg->len); + + writel(buf[0], drv_data->reg_base + MV64XXX_I2C_REG_TX_DATA_LO); + writel(buf[1], drv_data->reg_base + MV64XXX_I2C_REG_TX_DATA_HI); +} + +static int +mv64xxx_i2c_offload_xfer(struct mv64xxx_i2c_data *drv_data) +{ + struct i2c_msg *msgs = drv_data->msgs; + int num = drv_data->num_msgs; + unsigned long ctrl_reg; + unsigned long flags; + + spin_lock_irqsave(&drv_data->lock, flags); + + /* Build transaction */ + ctrl_reg = MV64XXX_I2C_BRIDGE_CONTROL_ENABLE | + (msgs[0].addr << MV64XXX_I2C_BRIDGE_CONTROL_ADDR_SHIFT); + + if (msgs[0].flags & I2C_M_TEN) + ctrl_reg |= MV64XXX_I2C_BRIDGE_CONTROL_ADDR_EXT; + + /* Single write message transaction */ + if (num == 1 && !(msgs[0].flags & I2C_M_RD)) { + size_t len = msgs[0].len - 1; + + ctrl_reg |= MV64XXX_I2C_BRIDGE_CONTROL_WR | + (len << MV64XXX_I2C_BRIDGE_CONTROL_TX_SIZE_SHIFT); + mv64xxx_i2c_prepare_tx(drv_data); + } + /* Single read message transaction */ + else if (num == 1 && msgs[0].flags & I2C_M_RD) { + size_t len = msgs[0].len - 1; + + ctrl_reg |= MV64XXX_I2C_BRIDGE_CONTROL_RD | + (len << MV64XXX_I2C_BRIDGE_CONTROL_RX_SIZE_SHIFT); + } + /* + * Transaction with one write and one read message. This is + * guaranteed by the mv64xx_i2c_can_offload() checks. + */ + else if (num == 2) { + size_t lentx = msgs[0].len - 1; + size_t lenrx = msgs[1].len - 1; + + ctrl_reg |= + MV64XXX_I2C_BRIDGE_CONTROL_RD | + MV64XXX_I2C_BRIDGE_CONTROL_WR | + (lentx << MV64XXX_I2C_BRIDGE_CONTROL_TX_SIZE_SHIFT) | + (lenrx << MV64XXX_I2C_BRIDGE_CONTROL_RX_SIZE_SHIFT) | + MV64XXX_I2C_BRIDGE_CONTROL_REPEATED_START; + mv64xxx_i2c_prepare_tx(drv_data); + } + + /* Execute transaction */ + drv_data->block = 1; + writel(ctrl_reg, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_CONTROL); + spin_unlock_irqrestore(&drv_data->lock, flags); + + mv64xxx_i2c_wait_for_completion(drv_data); + + return drv_data->rc; +} + +static bool +mv64xxx_i2c_valid_offload_sz(struct i2c_msg *msg) +{ + return msg->len <= 8 && msg->len >= 1; +} + +static bool +mv64xxx_i2c_can_offload(struct mv64xxx_i2c_data *drv_data) +{ + struct i2c_msg *msgs = drv_data->msgs; + int num = drv_data->num_msgs; + + if (!drv_data->offload_enabled) + return false; + + /* + * We can offload a transaction consisting of a single + * message, as long as the message has a length between 1 and + * 8 bytes. + */ + if (num == 1 && mv64xxx_i2c_valid_offload_sz(msgs)) + return true; + + /* + * We can offload a transaction consisting of two messages, if + * the first is a write and a second is a read, and both have + * a length between 1 and 8 bytes. + */ + if (num == 2 && + mv64xxx_i2c_valid_offload_sz(msgs) && + mv64xxx_i2c_valid_offload_sz(msgs + 1) && + !(msgs[0].flags & I2C_M_RD) && + msgs[1].flags & I2C_M_RD) + return true; + + return false; +} + +/* + ***************************************************************************** + * + * I2C Core Support Routines (Interface to higher level I2C code) + * + ***************************************************************************** + */ +static u32 +mv64xxx_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SMBUS_EMUL; +} + +static int +mv64xxx_i2c_xfer_core(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + struct mv64xxx_i2c_data *drv_data = i2c_get_adapdata(adap); + int rc, ret = num; + + rc = pm_runtime_resume_and_get(&adap->dev); + if (rc) + return rc; + + BUG_ON(drv_data->msgs != NULL); + drv_data->msgs = msgs; + drv_data->num_msgs = num; + + if (mv64xxx_i2c_can_offload(drv_data) && !drv_data->atomic) + rc = mv64xxx_i2c_offload_xfer(drv_data); + else + rc = mv64xxx_i2c_execute_msg(drv_data, &msgs[0], num == 1); + + if (rc < 0) + ret = rc; + + drv_data->num_msgs = 0; + drv_data->msgs = NULL; + + pm_runtime_mark_last_busy(&adap->dev); + pm_runtime_put_autosuspend(&adap->dev); + + return ret; +} + +static int +mv64xxx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + struct mv64xxx_i2c_data *drv_data = i2c_get_adapdata(adap); + + drv_data->atomic = 0; + return mv64xxx_i2c_xfer_core(adap, msgs, num); +} + +static int mv64xxx_i2c_xfer_atomic(struct i2c_adapter *adap, + struct i2c_msg msgs[], int num) +{ + struct mv64xxx_i2c_data *drv_data = i2c_get_adapdata(adap); + + drv_data->atomic = 1; + return mv64xxx_i2c_xfer_core(adap, msgs, num); +} + +static const struct i2c_algorithm mv64xxx_i2c_algo = { + .master_xfer = mv64xxx_i2c_xfer, + .master_xfer_atomic = mv64xxx_i2c_xfer_atomic, + .functionality = mv64xxx_i2c_functionality, +}; + +/* + ***************************************************************************** + * + * Driver Interface & Early Init Routines + * + ***************************************************************************** + */ +static const struct of_device_id mv64xxx_i2c_of_match_table[] = { + { .compatible = "allwinner,sun4i-a10-i2c", .data = &mv64xxx_i2c_regs_sun4i}, + { .compatible = "allwinner,sun6i-a31-i2c", .data = &mv64xxx_i2c_regs_sun4i}, + { .compatible = "marvell,mv64xxx-i2c", .data = &mv64xxx_i2c_regs_mv64xxx}, + { .compatible = "marvell,mv78230-i2c", .data = &mv64xxx_i2c_regs_mv64xxx}, + { .compatible = "marvell,mv78230-a0-i2c", .data = &mv64xxx_i2c_regs_mv64xxx}, + {} +}; +MODULE_DEVICE_TABLE(of, mv64xxx_i2c_of_match_table); + +#ifdef CONFIG_OF +static int +mv64xxx_calc_freq(struct mv64xxx_i2c_data *drv_data, + const int tclk, const int n, const int m) +{ + if (drv_data->clk_n_base_0) + return tclk / (10 * (m + 1) * (1 << n)); + else + return tclk / (10 * (m + 1) * (2 << n)); +} + +static bool +mv64xxx_find_baud_factors(struct mv64xxx_i2c_data *drv_data, + const u32 req_freq, const u32 tclk) +{ + int freq, delta, best_delta = INT_MAX; + int m, n; + + for (n = 0; n <= 7; n++) + for (m = 0; m <= 15; m++) { + freq = mv64xxx_calc_freq(drv_data, tclk, n, m); + delta = req_freq - freq; + if (delta >= 0 && delta < best_delta) { + drv_data->freq_m = m; + drv_data->freq_n = n; + best_delta = delta; + } + if (best_delta == 0) + return true; + } + if (best_delta == INT_MAX) + return false; + return true; +} + +static int +mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data, + struct device *dev) +{ + const struct of_device_id *device; + struct device_node *np = dev->of_node; + u32 bus_freq, tclk; + int rc = 0; + + /* CLK is mandatory when using DT to describe the i2c bus. We + * need to know tclk in order to calculate bus clock + * factors. + */ + if (!drv_data->clk) { + rc = -ENODEV; + goto out; + } + tclk = clk_get_rate(drv_data->clk); + + if (of_property_read_u32(np, "clock-frequency", &bus_freq)) + bus_freq = I2C_MAX_STANDARD_MODE_FREQ; /* 100kHz by default */ + + if (of_device_is_compatible(np, "allwinner,sun4i-a10-i2c") || + of_device_is_compatible(np, "allwinner,sun6i-a31-i2c")) + drv_data->clk_n_base_0 = true; + + if (!mv64xxx_find_baud_factors(drv_data, bus_freq, tclk)) { + rc = -EINVAL; + goto out; + } + + drv_data->rstc = devm_reset_control_get_optional_exclusive(dev, NULL); + if (IS_ERR(drv_data->rstc)) { + rc = PTR_ERR(drv_data->rstc); + goto out; + } + + /* Its not yet defined how timeouts will be specified in device tree. + * So hard code the value to 1 second. + */ + drv_data->adapter.timeout = HZ; + + device = of_match_device(mv64xxx_i2c_of_match_table, dev); + if (!device) + return -ENODEV; + + memcpy(&drv_data->reg_offsets, device->data, sizeof(drv_data->reg_offsets)); + + /* + * For controllers embedded in new SoCs activate the + * Transaction Generator support and the errata fix. + */ + if (of_device_is_compatible(np, "marvell,mv78230-i2c")) { + drv_data->offload_enabled = true; + /* The delay is only needed in standard mode (100kHz) */ + if (bus_freq <= I2C_MAX_STANDARD_MODE_FREQ) + drv_data->errata_delay = true; + } + + if (of_device_is_compatible(np, "marvell,mv78230-a0-i2c")) { + drv_data->offload_enabled = false; + /* The delay is only needed in standard mode (100kHz) */ + if (bus_freq <= I2C_MAX_STANDARD_MODE_FREQ) + drv_data->errata_delay = true; + } + + if (of_device_is_compatible(np, "allwinner,sun6i-a31-i2c")) + drv_data->irq_clear_inverted = true; + +out: + return rc; +} +#else /* CONFIG_OF */ +static int +mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data, + struct device *dev) +{ + return -ENODEV; +} +#endif /* CONFIG_OF */ + +static int mv64xxx_i2c_init_recovery_info(struct mv64xxx_i2c_data *drv_data, + struct device *dev) +{ + struct i2c_bus_recovery_info *rinfo = &drv_data->rinfo; + + rinfo->pinctrl = devm_pinctrl_get(dev); + if (IS_ERR(rinfo->pinctrl)) { + if (PTR_ERR(rinfo->pinctrl) == -EPROBE_DEFER) + return -EPROBE_DEFER; + dev_info(dev, "can't get pinctrl, bus recovery not supported\n"); + return PTR_ERR(rinfo->pinctrl); + } else if (!rinfo->pinctrl) { + return -ENODEV; + } + + drv_data->adapter.bus_recovery_info = rinfo; + return 0; +} + +static int +mv64xxx_i2c_runtime_suspend(struct device *dev) +{ + struct mv64xxx_i2c_data *drv_data = dev_get_drvdata(dev); + + reset_control_assert(drv_data->rstc); + clk_disable_unprepare(drv_data->reg_clk); + clk_disable_unprepare(drv_data->clk); + + return 0; +} + +static int +mv64xxx_i2c_runtime_resume(struct device *dev) +{ + struct mv64xxx_i2c_data *drv_data = dev_get_drvdata(dev); + + clk_prepare_enable(drv_data->clk); + clk_prepare_enable(drv_data->reg_clk); + reset_control_reset(drv_data->rstc); + + mv64xxx_i2c_hw_init(drv_data); + + return 0; +} + +static int +mv64xxx_i2c_probe(struct platform_device *pd) +{ + struct mv64xxx_i2c_data *drv_data; + struct mv64xxx_i2c_pdata *pdata = dev_get_platdata(&pd->dev); + int rc; + + if ((!pdata && !pd->dev.of_node)) + return -ENODEV; + + drv_data = devm_kzalloc(&pd->dev, sizeof(struct mv64xxx_i2c_data), + GFP_KERNEL); + if (!drv_data) + return -ENOMEM; + + drv_data->reg_base = devm_platform_ioremap_resource(pd, 0); + if (IS_ERR(drv_data->reg_base)) + return PTR_ERR(drv_data->reg_base); + + strscpy(drv_data->adapter.name, MV64XXX_I2C_CTLR_NAME " adapter", + sizeof(drv_data->adapter.name)); + + init_waitqueue_head(&drv_data->waitq); + spin_lock_init(&drv_data->lock); + + /* Not all platforms have clocks */ + drv_data->clk = devm_clk_get(&pd->dev, NULL); + if (IS_ERR(drv_data->clk)) { + if (PTR_ERR(drv_data->clk) == -EPROBE_DEFER) + return -EPROBE_DEFER; + drv_data->clk = NULL; + } + + drv_data->reg_clk = devm_clk_get(&pd->dev, "reg"); + if (IS_ERR(drv_data->reg_clk)) { + if (PTR_ERR(drv_data->reg_clk) == -EPROBE_DEFER) + return -EPROBE_DEFER; + drv_data->reg_clk = NULL; + } + + drv_data->irq = platform_get_irq(pd, 0); + if (drv_data->irq < 0) + return drv_data->irq; + + if (pdata) { + drv_data->freq_m = pdata->freq_m; + drv_data->freq_n = pdata->freq_n; + drv_data->adapter.timeout = msecs_to_jiffies(pdata->timeout); + drv_data->offload_enabled = false; + memcpy(&drv_data->reg_offsets, &mv64xxx_i2c_regs_mv64xxx, sizeof(drv_data->reg_offsets)); + } else if (pd->dev.of_node) { + rc = mv64xxx_of_config(drv_data, &pd->dev); + if (rc) + return rc; + } + + rc = mv64xxx_i2c_init_recovery_info(drv_data, &pd->dev); + if (rc == -EPROBE_DEFER) + return rc; + + drv_data->adapter.dev.parent = &pd->dev; + drv_data->adapter.algo = &mv64xxx_i2c_algo; + drv_data->adapter.owner = THIS_MODULE; + drv_data->adapter.class = I2C_CLASS_DEPRECATED; + drv_data->adapter.nr = pd->id; + drv_data->adapter.dev.of_node = pd->dev.of_node; + platform_set_drvdata(pd, drv_data); + i2c_set_adapdata(&drv_data->adapter, drv_data); + + pm_runtime_set_autosuspend_delay(&pd->dev, MSEC_PER_SEC); + pm_runtime_use_autosuspend(&pd->dev); + pm_runtime_enable(&pd->dev); + if (!pm_runtime_enabled(&pd->dev)) { + rc = mv64xxx_i2c_runtime_resume(&pd->dev); + if (rc) + goto exit_disable_pm; + } + + rc = request_irq(drv_data->irq, mv64xxx_i2c_intr, 0, + MV64XXX_I2C_CTLR_NAME, drv_data); + if (rc) { + dev_err(&drv_data->adapter.dev, + "mv64xxx: Can't register intr handler irq%d: %d\n", + drv_data->irq, rc); + goto exit_disable_pm; + } else if ((rc = i2c_add_numbered_adapter(&drv_data->adapter)) != 0) { + dev_err(&drv_data->adapter.dev, + "mv64xxx: Can't add i2c adapter, rc: %d\n", -rc); + goto exit_free_irq; + } + + return 0; + +exit_free_irq: + free_irq(drv_data->irq, drv_data); +exit_disable_pm: + pm_runtime_disable(&pd->dev); + if (!pm_runtime_status_suspended(&pd->dev)) + mv64xxx_i2c_runtime_suspend(&pd->dev); + + return rc; +} + +static void +mv64xxx_i2c_remove(struct platform_device *pd) +{ + struct mv64xxx_i2c_data *drv_data = platform_get_drvdata(pd); + + i2c_del_adapter(&drv_data->adapter); + free_irq(drv_data->irq, drv_data); + pm_runtime_disable(&pd->dev); + if (!pm_runtime_status_suspended(&pd->dev)) + mv64xxx_i2c_runtime_suspend(&pd->dev); +} + +static const struct dev_pm_ops mv64xxx_i2c_pm_ops = { + SET_RUNTIME_PM_OPS(mv64xxx_i2c_runtime_suspend, + mv64xxx_i2c_runtime_resume, NULL) + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) +}; + +static struct platform_driver mv64xxx_i2c_driver = { + .probe = mv64xxx_i2c_probe, + .remove_new = mv64xxx_i2c_remove, + .driver = { + .name = MV64XXX_I2C_CTLR_NAME, + .pm = &mv64xxx_i2c_pm_ops, + .of_match_table = mv64xxx_i2c_of_match_table, + }, +}; + +module_platform_driver(mv64xxx_i2c_driver); + +MODULE_AUTHOR("Mark A. Greer <mgreer@mvista.com>"); +MODULE_DESCRIPTION("Marvell mv64xxx host bridge i2c ctlr driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c new file mode 100644 index 000000000..36def0a9c --- /dev/null +++ b/drivers/i2c/busses/i2c-mxs.c @@ -0,0 +1,903 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Freescale MXS I2C bus driver + * + * Copyright (C) 2012-2013 Marek Vasut <marex@denx.de> + * Copyright (C) 2011-2012 Wolfram Sang, Pengutronix e.K. + * + * based on a (non-working) driver which was: + * + * Copyright (C) 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +#include <linux/slab.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/completion.h> +#include <linux/platform_device.h> +#include <linux/jiffies.h> +#include <linux/io.h> +#include <linux/stmp_device.h> +#include <linux/of.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/dma/mxs-dma.h> + +#define DRIVER_NAME "mxs-i2c" + +#define MXS_I2C_CTRL0 (0x00) +#define MXS_I2C_CTRL0_SET (0x04) +#define MXS_I2C_CTRL0_CLR (0x08) + +#define MXS_I2C_CTRL0_SFTRST 0x80000000 +#define MXS_I2C_CTRL0_RUN 0x20000000 +#define MXS_I2C_CTRL0_SEND_NAK_ON_LAST 0x02000000 +#define MXS_I2C_CTRL0_PIO_MODE 0x01000000 +#define MXS_I2C_CTRL0_RETAIN_CLOCK 0x00200000 +#define MXS_I2C_CTRL0_POST_SEND_STOP 0x00100000 +#define MXS_I2C_CTRL0_PRE_SEND_START 0x00080000 +#define MXS_I2C_CTRL0_MASTER_MODE 0x00020000 +#define MXS_I2C_CTRL0_DIRECTION 0x00010000 +#define MXS_I2C_CTRL0_XFER_COUNT(v) ((v) & 0x0000FFFF) + +#define MXS_I2C_TIMING0 (0x10) +#define MXS_I2C_TIMING1 (0x20) +#define MXS_I2C_TIMING2 (0x30) + +#define MXS_I2C_CTRL1 (0x40) +#define MXS_I2C_CTRL1_SET (0x44) +#define MXS_I2C_CTRL1_CLR (0x48) + +#define MXS_I2C_CTRL1_CLR_GOT_A_NAK 0x10000000 +#define MXS_I2C_CTRL1_BUS_FREE_IRQ 0x80 +#define MXS_I2C_CTRL1_DATA_ENGINE_CMPLT_IRQ 0x40 +#define MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ 0x20 +#define MXS_I2C_CTRL1_OVERSIZE_XFER_TERM_IRQ 0x10 +#define MXS_I2C_CTRL1_EARLY_TERM_IRQ 0x08 +#define MXS_I2C_CTRL1_MASTER_LOSS_IRQ 0x04 +#define MXS_I2C_CTRL1_SLAVE_STOP_IRQ 0x02 +#define MXS_I2C_CTRL1_SLAVE_IRQ 0x01 + +#define MXS_I2C_STAT (0x50) +#define MXS_I2C_STAT_GOT_A_NAK 0x10000000 +#define MXS_I2C_STAT_BUS_BUSY 0x00000800 +#define MXS_I2C_STAT_CLK_GEN_BUSY 0x00000400 + +#define MXS_I2C_DATA(i2c) ((i2c->dev_type == MXS_I2C_V1) ? 0x60 : 0xa0) + +#define MXS_I2C_DEBUG0_CLR(i2c) ((i2c->dev_type == MXS_I2C_V1) ? 0x78 : 0xb8) + +#define MXS_I2C_DEBUG0_DMAREQ 0x80000000 + +#define MXS_I2C_IRQ_MASK (MXS_I2C_CTRL1_DATA_ENGINE_CMPLT_IRQ | \ + MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ | \ + MXS_I2C_CTRL1_EARLY_TERM_IRQ | \ + MXS_I2C_CTRL1_MASTER_LOSS_IRQ | \ + MXS_I2C_CTRL1_SLAVE_STOP_IRQ | \ + MXS_I2C_CTRL1_SLAVE_IRQ) + + +#define MXS_CMD_I2C_SELECT (MXS_I2C_CTRL0_RETAIN_CLOCK | \ + MXS_I2C_CTRL0_PRE_SEND_START | \ + MXS_I2C_CTRL0_MASTER_MODE | \ + MXS_I2C_CTRL0_DIRECTION | \ + MXS_I2C_CTRL0_XFER_COUNT(1)) + +#define MXS_CMD_I2C_WRITE (MXS_I2C_CTRL0_PRE_SEND_START | \ + MXS_I2C_CTRL0_MASTER_MODE | \ + MXS_I2C_CTRL0_DIRECTION) + +#define MXS_CMD_I2C_READ (MXS_I2C_CTRL0_SEND_NAK_ON_LAST | \ + MXS_I2C_CTRL0_MASTER_MODE) + +enum mxs_i2c_devtype { + MXS_I2C_UNKNOWN = 0, + MXS_I2C_V1, + MXS_I2C_V2, +}; + +/** + * struct mxs_i2c_dev - per device, private MXS-I2C data + * + * @dev: driver model device node + * @dev_type: distinguish i.MX23/i.MX28 features + * @regs: IO registers pointer + * @cmd_complete: completion object for transaction wait + * @cmd_err: error code for last transaction + * @adapter: i2c subsystem adapter node + */ +struct mxs_i2c_dev { + struct device *dev; + enum mxs_i2c_devtype dev_type; + void __iomem *regs; + struct completion cmd_complete; + int cmd_err; + struct i2c_adapter adapter; + + uint32_t timing0; + uint32_t timing1; + uint32_t timing2; + + /* DMA support components */ + struct dma_chan *dmach; + uint32_t pio_data[2]; + uint32_t addr_data; + struct scatterlist sg_io[2]; + bool dma_read; +}; + +static int mxs_i2c_reset(struct mxs_i2c_dev *i2c) +{ + int ret = stmp_reset_block(i2c->regs); + if (ret) + return ret; + + /* + * Configure timing for the I2C block. The I2C TIMING2 register has to + * be programmed with this particular magic number. The rest is derived + * from the XTAL speed and requested I2C speed. + * + * For details, see i.MX233 [25.4.2 - 25.4.4] and i.MX28 [27.5.2 - 27.5.4]. + */ + writel(i2c->timing0, i2c->regs + MXS_I2C_TIMING0); + writel(i2c->timing1, i2c->regs + MXS_I2C_TIMING1); + writel(i2c->timing2, i2c->regs + MXS_I2C_TIMING2); + + writel(MXS_I2C_IRQ_MASK << 8, i2c->regs + MXS_I2C_CTRL1_SET); + + return 0; +} + +static void mxs_i2c_dma_finish(struct mxs_i2c_dev *i2c) +{ + if (i2c->dma_read) { + dma_unmap_sg(i2c->dev, &i2c->sg_io[0], 1, DMA_TO_DEVICE); + dma_unmap_sg(i2c->dev, &i2c->sg_io[1], 1, DMA_FROM_DEVICE); + } else { + dma_unmap_sg(i2c->dev, i2c->sg_io, 2, DMA_TO_DEVICE); + } +} + +static void mxs_i2c_dma_irq_callback(void *param) +{ + struct mxs_i2c_dev *i2c = param; + + complete(&i2c->cmd_complete); + mxs_i2c_dma_finish(i2c); +} + +static int mxs_i2c_dma_setup_xfer(struct i2c_adapter *adap, + struct i2c_msg *msg, u8 *buf, uint32_t flags) +{ + struct dma_async_tx_descriptor *desc; + struct mxs_i2c_dev *i2c = i2c_get_adapdata(adap); + + i2c->addr_data = i2c_8bit_addr_from_msg(msg); + + if (msg->flags & I2C_M_RD) { + i2c->dma_read = true; + + /* + * SELECT command. + */ + + /* Queue the PIO register write transfer. */ + i2c->pio_data[0] = MXS_CMD_I2C_SELECT; + desc = dmaengine_prep_slave_sg(i2c->dmach, + (struct scatterlist *)&i2c->pio_data[0], + 1, DMA_TRANS_NONE, 0); + if (!desc) { + dev_err(i2c->dev, + "Failed to get PIO reg. write descriptor.\n"); + goto select_init_pio_fail; + } + + /* Queue the DMA data transfer. */ + sg_init_one(&i2c->sg_io[0], &i2c->addr_data, 1); + dma_map_sg(i2c->dev, &i2c->sg_io[0], 1, DMA_TO_DEVICE); + desc = dmaengine_prep_slave_sg(i2c->dmach, &i2c->sg_io[0], 1, + DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | + MXS_DMA_CTRL_WAIT4END); + if (!desc) { + dev_err(i2c->dev, + "Failed to get DMA data write descriptor.\n"); + goto select_init_dma_fail; + } + + /* + * READ command. + */ + + /* Queue the PIO register write transfer. */ + i2c->pio_data[1] = flags | MXS_CMD_I2C_READ | + MXS_I2C_CTRL0_XFER_COUNT(msg->len); + desc = dmaengine_prep_slave_sg(i2c->dmach, + (struct scatterlist *)&i2c->pio_data[1], + 1, DMA_TRANS_NONE, DMA_PREP_INTERRUPT); + if (!desc) { + dev_err(i2c->dev, + "Failed to get PIO reg. write descriptor.\n"); + goto select_init_dma_fail; + } + + /* Queue the DMA data transfer. */ + sg_init_one(&i2c->sg_io[1], buf, msg->len); + dma_map_sg(i2c->dev, &i2c->sg_io[1], 1, DMA_FROM_DEVICE); + desc = dmaengine_prep_slave_sg(i2c->dmach, &i2c->sg_io[1], 1, + DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | + MXS_DMA_CTRL_WAIT4END); + if (!desc) { + dev_err(i2c->dev, + "Failed to get DMA data write descriptor.\n"); + goto read_init_dma_fail; + } + } else { + i2c->dma_read = false; + + /* + * WRITE command. + */ + + /* Queue the PIO register write transfer. */ + i2c->pio_data[0] = flags | MXS_CMD_I2C_WRITE | + MXS_I2C_CTRL0_XFER_COUNT(msg->len + 1); + desc = dmaengine_prep_slave_sg(i2c->dmach, + (struct scatterlist *)&i2c->pio_data[0], + 1, DMA_TRANS_NONE, 0); + if (!desc) { + dev_err(i2c->dev, + "Failed to get PIO reg. write descriptor.\n"); + goto write_init_pio_fail; + } + + /* Queue the DMA data transfer. */ + sg_init_table(i2c->sg_io, 2); + sg_set_buf(&i2c->sg_io[0], &i2c->addr_data, 1); + sg_set_buf(&i2c->sg_io[1], buf, msg->len); + dma_map_sg(i2c->dev, i2c->sg_io, 2, DMA_TO_DEVICE); + desc = dmaengine_prep_slave_sg(i2c->dmach, i2c->sg_io, 2, + DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | + MXS_DMA_CTRL_WAIT4END); + if (!desc) { + dev_err(i2c->dev, + "Failed to get DMA data write descriptor.\n"); + goto write_init_dma_fail; + } + } + + /* + * The last descriptor must have this callback, + * to finish the DMA transaction. + */ + desc->callback = mxs_i2c_dma_irq_callback; + desc->callback_param = i2c; + + /* Start the transfer. */ + dmaengine_submit(desc); + dma_async_issue_pending(i2c->dmach); + return 0; + +/* Read failpath. */ +read_init_dma_fail: + dma_unmap_sg(i2c->dev, &i2c->sg_io[1], 1, DMA_FROM_DEVICE); +select_init_dma_fail: + dma_unmap_sg(i2c->dev, &i2c->sg_io[0], 1, DMA_TO_DEVICE); +select_init_pio_fail: + dmaengine_terminate_sync(i2c->dmach); + return -EINVAL; + +/* Write failpath. */ +write_init_dma_fail: + dma_unmap_sg(i2c->dev, i2c->sg_io, 2, DMA_TO_DEVICE); +write_init_pio_fail: + dmaengine_terminate_sync(i2c->dmach); + return -EINVAL; +} + +static int mxs_i2c_pio_wait_xfer_end(struct mxs_i2c_dev *i2c) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(1000); + + while (readl(i2c->regs + MXS_I2C_CTRL0) & MXS_I2C_CTRL0_RUN) { + if (readl(i2c->regs + MXS_I2C_CTRL1) & + MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ) + return -ENXIO; + if (time_after(jiffies, timeout)) + return -ETIMEDOUT; + cond_resched(); + } + + return 0; +} + +static int mxs_i2c_pio_check_error_state(struct mxs_i2c_dev *i2c) +{ + u32 state; + + state = readl(i2c->regs + MXS_I2C_CTRL1_CLR) & MXS_I2C_IRQ_MASK; + + if (state & MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ) + i2c->cmd_err = -ENXIO; + else if (state & (MXS_I2C_CTRL1_EARLY_TERM_IRQ | + MXS_I2C_CTRL1_MASTER_LOSS_IRQ | + MXS_I2C_CTRL1_SLAVE_STOP_IRQ | + MXS_I2C_CTRL1_SLAVE_IRQ)) + i2c->cmd_err = -EIO; + + return i2c->cmd_err; +} + +static void mxs_i2c_pio_trigger_cmd(struct mxs_i2c_dev *i2c, u32 cmd) +{ + u32 reg; + + writel(cmd, i2c->regs + MXS_I2C_CTRL0); + + /* readback makes sure the write is latched into hardware */ + reg = readl(i2c->regs + MXS_I2C_CTRL0); + reg |= MXS_I2C_CTRL0_RUN; + writel(reg, i2c->regs + MXS_I2C_CTRL0); +} + +/* + * Start WRITE transaction on the I2C bus. By studying i.MX23 datasheet, + * CTRL0::PIO_MODE bit description clarifies the order in which the registers + * must be written during PIO mode operation. First, the CTRL0 register has + * to be programmed with all the necessary bits but the RUN bit. Then the + * payload has to be written into the DATA register. Finally, the transmission + * is executed by setting the RUN bit in CTRL0. + */ +static void mxs_i2c_pio_trigger_write_cmd(struct mxs_i2c_dev *i2c, u32 cmd, + u32 data) +{ + writel(cmd, i2c->regs + MXS_I2C_CTRL0); + + if (i2c->dev_type == MXS_I2C_V1) + writel(MXS_I2C_CTRL0_PIO_MODE, i2c->regs + MXS_I2C_CTRL0_SET); + + writel(data, i2c->regs + MXS_I2C_DATA(i2c)); + writel(MXS_I2C_CTRL0_RUN, i2c->regs + MXS_I2C_CTRL0_SET); +} + +static int mxs_i2c_pio_setup_xfer(struct i2c_adapter *adap, + struct i2c_msg *msg, uint32_t flags) +{ + struct mxs_i2c_dev *i2c = i2c_get_adapdata(adap); + uint32_t addr_data = i2c_8bit_addr_from_msg(msg); + uint32_t data = 0; + int i, ret, xlen = 0, xmit = 0; + uint32_t start; + + /* Mute IRQs coming from this block. */ + writel(MXS_I2C_IRQ_MASK << 8, i2c->regs + MXS_I2C_CTRL1_CLR); + + /* + * MX23 idea: + * - Enable CTRL0::PIO_MODE (1 << 24) + * - Enable CTRL1::ACK_MODE (1 << 27) + * + * WARNING! The MX23 is broken in some way, even if it claims + * to support PIO, when we try to transfer any amount of data + * that is not aligned to 4 bytes, the DMA engine will have + * bits in DEBUG1::DMA_BYTES_ENABLES still set even after the + * transfer. This in turn will mess up the next transfer as + * the block it emit one byte write onto the bus terminated + * with a NAK+STOP. A possible workaround is to reset the IP + * block after every PIO transmission, which might just work. + * + * NOTE: The CTRL0::PIO_MODE description is important, since + * it outlines how the PIO mode is really supposed to work. + */ + if (msg->flags & I2C_M_RD) { + /* + * PIO READ transfer: + * + * This transfer MUST be limited to 4 bytes maximum. It is not + * possible to transfer more than four bytes via PIO, since we + * can not in any way make sure we can read the data from the + * DATA register fast enough. Besides, the RX FIFO is only four + * bytes deep, thus we can only really read up to four bytes at + * time. Finally, there is no bit indicating us that new data + * arrived at the FIFO and can thus be fetched from the DATA + * register. + */ + BUG_ON(msg->len > 4); + + /* SELECT command. */ + mxs_i2c_pio_trigger_write_cmd(i2c, MXS_CMD_I2C_SELECT, + addr_data); + + ret = mxs_i2c_pio_wait_xfer_end(i2c); + if (ret) { + dev_dbg(i2c->dev, + "PIO: Failed to send SELECT command!\n"); + goto cleanup; + } + + /* READ command. */ + mxs_i2c_pio_trigger_cmd(i2c, + MXS_CMD_I2C_READ | flags | + MXS_I2C_CTRL0_XFER_COUNT(msg->len)); + + ret = mxs_i2c_pio_wait_xfer_end(i2c); + if (ret) { + dev_dbg(i2c->dev, + "PIO: Failed to send READ command!\n"); + goto cleanup; + } + + data = readl(i2c->regs + MXS_I2C_DATA(i2c)); + for (i = 0; i < msg->len; i++) { + msg->buf[i] = data & 0xff; + data >>= 8; + } + } else { + /* + * PIO WRITE transfer: + * + * The code below implements clock stretching to circumvent + * the possibility of kernel not being able to supply data + * fast enough. It is possible to transfer arbitrary amount + * of data using PIO write. + */ + + /* + * The LSB of data buffer is the first byte blasted across + * the bus. Higher order bytes follow. Thus the following + * filling schematic. + */ + + data = addr_data << 24; + + /* Start the transfer with START condition. */ + start = MXS_I2C_CTRL0_PRE_SEND_START; + + /* If the transfer is long, use clock stretching. */ + if (msg->len > 3) + start |= MXS_I2C_CTRL0_RETAIN_CLOCK; + + for (i = 0; i < msg->len; i++) { + data >>= 8; + data |= (msg->buf[i] << 24); + + xmit = 0; + + /* This is the last transfer of the message. */ + if (i + 1 == msg->len) { + /* Add optional STOP flag. */ + start |= flags; + /* Remove RETAIN_CLOCK bit. */ + start &= ~MXS_I2C_CTRL0_RETAIN_CLOCK; + xmit = 1; + } + + /* Four bytes are ready in the "data" variable. */ + if ((i & 3) == 2) + xmit = 1; + + /* Nothing interesting happened, continue stuffing. */ + if (!xmit) + continue; + + /* + * Compute the size of the transfer and shift the + * data accordingly. + * + * i = (4k + 0) .... xlen = 2 + * i = (4k + 1) .... xlen = 3 + * i = (4k + 2) .... xlen = 4 + * i = (4k + 3) .... xlen = 1 + */ + + if ((i % 4) == 3) + xlen = 1; + else + xlen = (i % 4) + 2; + + data >>= (4 - xlen) * 8; + + dev_dbg(i2c->dev, + "PIO: len=%i pos=%i total=%i [W%s%s%s]\n", + xlen, i, msg->len, + start & MXS_I2C_CTRL0_PRE_SEND_START ? "S" : "", + start & MXS_I2C_CTRL0_POST_SEND_STOP ? "E" : "", + start & MXS_I2C_CTRL0_RETAIN_CLOCK ? "C" : ""); + + writel(MXS_I2C_DEBUG0_DMAREQ, + i2c->regs + MXS_I2C_DEBUG0_CLR(i2c)); + + mxs_i2c_pio_trigger_write_cmd(i2c, + start | MXS_I2C_CTRL0_MASTER_MODE | + MXS_I2C_CTRL0_DIRECTION | + MXS_I2C_CTRL0_XFER_COUNT(xlen), data); + + /* The START condition is sent only once. */ + start &= ~MXS_I2C_CTRL0_PRE_SEND_START; + + /* Wait for the end of the transfer. */ + ret = mxs_i2c_pio_wait_xfer_end(i2c); + if (ret) { + dev_dbg(i2c->dev, + "PIO: Failed to finish WRITE cmd!\n"); + break; + } + + /* Check NAK here. */ + ret = readl(i2c->regs + MXS_I2C_STAT) & + MXS_I2C_STAT_GOT_A_NAK; + if (ret) { + ret = -ENXIO; + goto cleanup; + } + } + } + + /* make sure we capture any occurred error into cmd_err */ + ret = mxs_i2c_pio_check_error_state(i2c); + +cleanup: + /* Clear any dangling IRQs and re-enable interrupts. */ + writel(MXS_I2C_IRQ_MASK, i2c->regs + MXS_I2C_CTRL1_CLR); + writel(MXS_I2C_IRQ_MASK << 8, i2c->regs + MXS_I2C_CTRL1_SET); + + /* Clear the PIO_MODE on i.MX23 */ + if (i2c->dev_type == MXS_I2C_V1) + writel(MXS_I2C_CTRL0_PIO_MODE, i2c->regs + MXS_I2C_CTRL0_CLR); + + return ret; +} + +/* + * Low level master read/write transaction. + */ +static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, + int stop) +{ + struct mxs_i2c_dev *i2c = i2c_get_adapdata(adap); + int ret; + int flags; + u8 *dma_buf; + int use_pio = 0; + unsigned long time_left; + + flags = stop ? MXS_I2C_CTRL0_POST_SEND_STOP : 0; + + dev_dbg(i2c->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n", + msg->addr, msg->len, msg->flags, stop); + + /* + * The MX28 I2C IP block can only do PIO READ for transfer of to up + * 4 bytes of length. The write transfer is not limited as it can use + * clock stretching to avoid FIFO underruns. + */ + if ((msg->flags & I2C_M_RD) && (msg->len <= 4)) + use_pio = 1; + if (!(msg->flags & I2C_M_RD) && (msg->len < 7)) + use_pio = 1; + + i2c->cmd_err = 0; + if (use_pio) { + ret = mxs_i2c_pio_setup_xfer(adap, msg, flags); + /* No need to reset the block if NAK was received. */ + if (ret && (ret != -ENXIO)) + mxs_i2c_reset(i2c); + } else { + dma_buf = i2c_get_dma_safe_msg_buf(msg, 1); + if (!dma_buf) + return -ENOMEM; + + reinit_completion(&i2c->cmd_complete); + ret = mxs_i2c_dma_setup_xfer(adap, msg, dma_buf, flags); + if (ret) { + i2c_put_dma_safe_msg_buf(dma_buf, msg, false); + return ret; + } + + time_left = wait_for_completion_timeout(&i2c->cmd_complete, + msecs_to_jiffies(1000)); + i2c_put_dma_safe_msg_buf(dma_buf, msg, true); + if (!time_left) + goto timeout; + + ret = i2c->cmd_err; + } + + if (ret == -ENXIO) { + /* + * If the transfer fails with a NAK from the slave the + * controller halts until it gets told to return to idle state. + */ + writel(MXS_I2C_CTRL1_CLR_GOT_A_NAK, + i2c->regs + MXS_I2C_CTRL1_SET); + } + + /* + * WARNING! + * The i.MX23 is strange. After each and every operation, it's I2C IP + * block must be reset, otherwise the IP block will misbehave. This can + * be observed on the bus by the block sending out one single byte onto + * the bus. In case such an error happens, bit 27 will be set in the + * DEBUG0 register. This bit is not documented in the i.MX23 datasheet + * and is marked as "TBD" instead. To reset this bit to a correct state, + * reset the whole block. Since the block reset does not take long, do + * reset the block after every transfer to play safe. + */ + if (i2c->dev_type == MXS_I2C_V1) + mxs_i2c_reset(i2c); + + dev_dbg(i2c->dev, "Done with err=%d\n", ret); + + return ret; + +timeout: + dev_dbg(i2c->dev, "Timeout!\n"); + mxs_i2c_dma_finish(i2c); + ret = mxs_i2c_reset(i2c); + if (ret) + return ret; + + return -ETIMEDOUT; +} + +static int mxs_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], + int num) +{ + int i; + int err; + + for (i = 0; i < num; i++) { + err = mxs_i2c_xfer_msg(adap, &msgs[i], i == (num - 1)); + if (err) + return err; + } + + return num; +} + +static u32 mxs_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static irqreturn_t mxs_i2c_isr(int this_irq, void *dev_id) +{ + struct mxs_i2c_dev *i2c = dev_id; + u32 stat = readl(i2c->regs + MXS_I2C_CTRL1) & MXS_I2C_IRQ_MASK; + + if (!stat) + return IRQ_NONE; + + if (stat & MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ) + i2c->cmd_err = -ENXIO; + else if (stat & (MXS_I2C_CTRL1_EARLY_TERM_IRQ | + MXS_I2C_CTRL1_MASTER_LOSS_IRQ | + MXS_I2C_CTRL1_SLAVE_STOP_IRQ | MXS_I2C_CTRL1_SLAVE_IRQ)) + /* MXS_I2C_CTRL1_OVERSIZE_XFER_TERM_IRQ is only for slaves */ + i2c->cmd_err = -EIO; + + writel(stat, i2c->regs + MXS_I2C_CTRL1_CLR); + + return IRQ_HANDLED; +} + +static const struct i2c_algorithm mxs_i2c_algo = { + .master_xfer = mxs_i2c_xfer, + .functionality = mxs_i2c_func, +}; + +static const struct i2c_adapter_quirks mxs_i2c_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN, +}; + +static void mxs_i2c_derive_timing(struct mxs_i2c_dev *i2c, uint32_t speed) +{ + /* The I2C block clock runs at 24MHz */ + const uint32_t clk = 24000000; + uint32_t divider; + uint16_t high_count, low_count, rcv_count, xmit_count; + uint32_t bus_free, leadin; + struct device *dev = i2c->dev; + + divider = DIV_ROUND_UP(clk, speed); + + if (divider < 25) { + /* + * limit the divider, so that min(low_count, high_count) + * is >= 1 + */ + divider = 25; + dev_warn(dev, + "Speed too high (%u.%03u kHz), using %u.%03u kHz\n", + speed / 1000, speed % 1000, + clk / divider / 1000, clk / divider % 1000); + } else if (divider > 1897) { + /* + * limit the divider, so that max(low_count, high_count) + * cannot exceed 1023 + */ + divider = 1897; + dev_warn(dev, + "Speed too low (%u.%03u kHz), using %u.%03u kHz\n", + speed / 1000, speed % 1000, + clk / divider / 1000, clk / divider % 1000); + } + + /* + * The I2C spec specifies the following timing data: + * standard mode fast mode Bitfield name + * tLOW (SCL LOW period) 4700 ns 1300 ns + * tHIGH (SCL HIGH period) 4000 ns 600 ns + * tSU;DAT (data setup time) 250 ns 100 ns + * tHD;STA (START hold time) 4000 ns 600 ns + * tBUF (bus free time) 4700 ns 1300 ns + * + * The hardware (of the i.MX28 at least) seems to add 2 additional + * clock cycles to the low_count and 7 cycles to the high_count. + * This is compensated for by subtracting the respective constants + * from the values written to the timing registers. + */ + if (speed > I2C_MAX_STANDARD_MODE_FREQ) { + /* fast mode */ + low_count = DIV_ROUND_CLOSEST(divider * 13, (13 + 6)); + high_count = DIV_ROUND_CLOSEST(divider * 6, (13 + 6)); + leadin = DIV_ROUND_UP(600 * (clk / 1000000), 1000); + bus_free = DIV_ROUND_UP(1300 * (clk / 1000000), 1000); + } else { + /* normal mode */ + low_count = DIV_ROUND_CLOSEST(divider * 47, (47 + 40)); + high_count = DIV_ROUND_CLOSEST(divider * 40, (47 + 40)); + leadin = DIV_ROUND_UP(4700 * (clk / 1000000), 1000); + bus_free = DIV_ROUND_UP(4700 * (clk / 1000000), 1000); + } + rcv_count = high_count * 3 / 8; + xmit_count = low_count * 3 / 8; + + dev_dbg(dev, + "speed=%u(actual %u) divider=%u low=%u high=%u xmit=%u rcv=%u leadin=%u bus_free=%u\n", + speed, clk / divider, divider, low_count, high_count, + xmit_count, rcv_count, leadin, bus_free); + + low_count -= 2; + high_count -= 7; + i2c->timing0 = (high_count << 16) | rcv_count; + i2c->timing1 = (low_count << 16) | xmit_count; + i2c->timing2 = (bus_free << 16 | leadin); +} + +static int mxs_i2c_get_ofdata(struct mxs_i2c_dev *i2c) +{ + uint32_t speed; + struct device *dev = i2c->dev; + struct device_node *node = dev->of_node; + int ret; + + ret = of_property_read_u32(node, "clock-frequency", &speed); + if (ret) { + dev_warn(dev, "No I2C speed selected, using 100kHz\n"); + speed = I2C_MAX_STANDARD_MODE_FREQ; + } + + mxs_i2c_derive_timing(i2c, speed); + + return 0; +} + +static const struct of_device_id mxs_i2c_dt_ids[] = { + { .compatible = "fsl,imx23-i2c", .data = (void *)MXS_I2C_V1, }, + { .compatible = "fsl,imx28-i2c", .data = (void *)MXS_I2C_V2, }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, mxs_i2c_dt_ids); + +static int mxs_i2c_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct mxs_i2c_dev *i2c; + struct i2c_adapter *adap; + int err, irq; + + i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->dev_type = (uintptr_t)of_device_get_match_data(&pdev->dev); + + i2c->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c->regs)) + return PTR_ERR(i2c->regs); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + err = devm_request_irq(dev, irq, mxs_i2c_isr, 0, dev_name(dev), i2c); + if (err) + return err; + + i2c->dev = dev; + + init_completion(&i2c->cmd_complete); + + if (dev->of_node) { + err = mxs_i2c_get_ofdata(i2c); + if (err) + return err; + } + + /* Setup the DMA */ + i2c->dmach = dma_request_chan(dev, "rx-tx"); + if (IS_ERR(i2c->dmach)) { + return dev_err_probe(dev, PTR_ERR(i2c->dmach), + "Failed to request dma\n"); + } + + platform_set_drvdata(pdev, i2c); + + /* Do reset to enforce correct startup after pinmuxing */ + err = mxs_i2c_reset(i2c); + if (err) + return err; + + adap = &i2c->adapter; + strscpy(adap->name, "MXS I2C adapter", sizeof(adap->name)); + adap->owner = THIS_MODULE; + adap->algo = &mxs_i2c_algo; + adap->quirks = &mxs_i2c_quirks; + adap->dev.parent = dev; + adap->nr = pdev->id; + adap->dev.of_node = pdev->dev.of_node; + i2c_set_adapdata(adap, i2c); + err = i2c_add_numbered_adapter(adap); + if (err) { + writel(MXS_I2C_CTRL0_SFTRST, + i2c->regs + MXS_I2C_CTRL0_SET); + return err; + } + + return 0; +} + +static void mxs_i2c_remove(struct platform_device *pdev) +{ + struct mxs_i2c_dev *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adapter); + + if (i2c->dmach) + dma_release_channel(i2c->dmach); + + writel(MXS_I2C_CTRL0_SFTRST, i2c->regs + MXS_I2C_CTRL0_SET); +} + +static struct platform_driver mxs_i2c_driver = { + .driver = { + .name = DRIVER_NAME, + .of_match_table = mxs_i2c_dt_ids, + }, + .probe = mxs_i2c_probe, + .remove_new = mxs_i2c_remove, +}; + +static int __init mxs_i2c_init(void) +{ + return platform_driver_register(&mxs_i2c_driver); +} +subsys_initcall(mxs_i2c_init); + +static void __exit mxs_i2c_exit(void) +{ + platform_driver_unregister(&mxs_i2c_driver); +} +module_exit(mxs_i2c_exit); + +MODULE_AUTHOR("Marek Vasut <marex@denx.de>"); +MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>"); +MODULE_DESCRIPTION("MXS I2C Bus Driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRIVER_NAME); diff --git a/drivers/i2c/busses/i2c-nforce2-s4985.c b/drivers/i2c/busses/i2c-nforce2-s4985.c new file mode 100644 index 000000000..69a71bc98 --- /dev/null +++ b/drivers/i2c/busses/i2c-nforce2-s4985.c @@ -0,0 +1,240 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * i2c-nforce2-s4985.c - i2c-nforce2 extras for the Tyan S4985 motherboard + * + * Copyright (C) 2008 Jean Delvare <jdelvare@suse.de> + */ + +/* + * We select the channels by sending commands to the Philips + * PCA9556 chip at I2C address 0x18. The main adapter is used for + * the non-multiplexed part of the bus, and 4 virtual adapters + * are defined for the multiplexed addresses: 0x50-0x53 (memory + * module EEPROM) located on channels 1-4. We define one virtual + * adapter per CPU, which corresponds to one multiplexed channel: + * CPU0: virtual adapter 1, channel 1 + * CPU1: virtual adapter 2, channel 2 + * CPU2: virtual adapter 3, channel 3 + * CPU3: virtual adapter 4, channel 4 + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/mutex.h> + +extern struct i2c_adapter *nforce2_smbus; + +static struct i2c_adapter *s4985_adapter; +static struct i2c_algorithm *s4985_algo; + +/* Wrapper access functions for multiplexed SMBus */ +static DEFINE_MUTEX(nforce2_lock); + +static s32 nforce2_access_virt0(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + int error; + + /* We exclude the multiplexed addresses */ + if ((addr & 0xfc) == 0x50 || (addr & 0xfc) == 0x30 + || addr == 0x18) + return -ENXIO; + + mutex_lock(&nforce2_lock); + error = nforce2_smbus->algo->smbus_xfer(adap, addr, flags, read_write, + command, size, data); + mutex_unlock(&nforce2_lock); + + return error; +} + +/* We remember the last used channels combination so as to only switch + channels when it is really needed. This greatly reduces the SMBus + overhead, but also assumes that nobody will be writing to the PCA9556 + in our back. */ +static u8 last_channels; + +static inline s32 nforce2_access_channel(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data, + u8 channels) +{ + int error; + + /* We exclude the non-multiplexed addresses */ + if ((addr & 0xfc) != 0x50 && (addr & 0xfc) != 0x30) + return -ENXIO; + + mutex_lock(&nforce2_lock); + if (last_channels != channels) { + union i2c_smbus_data mplxdata; + mplxdata.byte = channels; + + error = nforce2_smbus->algo->smbus_xfer(adap, 0x18, 0, + I2C_SMBUS_WRITE, 0x01, + I2C_SMBUS_BYTE_DATA, + &mplxdata); + if (error) + goto UNLOCK; + last_channels = channels; + } + error = nforce2_smbus->algo->smbus_xfer(adap, addr, flags, read_write, + command, size, data); + +UNLOCK: + mutex_unlock(&nforce2_lock); + return error; +} + +static s32 nforce2_access_virt1(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + /* CPU0: channel 1 enabled */ + return nforce2_access_channel(adap, addr, flags, read_write, command, + size, data, 0x02); +} + +static s32 nforce2_access_virt2(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + /* CPU1: channel 2 enabled */ + return nforce2_access_channel(adap, addr, flags, read_write, command, + size, data, 0x04); +} + +static s32 nforce2_access_virt3(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + /* CPU2: channel 3 enabled */ + return nforce2_access_channel(adap, addr, flags, read_write, command, + size, data, 0x08); +} + +static s32 nforce2_access_virt4(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + /* CPU3: channel 4 enabled */ + return nforce2_access_channel(adap, addr, flags, read_write, command, + size, data, 0x10); +} + +static int __init nforce2_s4985_init(void) +{ + int i, error; + union i2c_smbus_data ioconfig; + + if (!nforce2_smbus) + return -ENODEV; + + /* Configure the PCA9556 multiplexer */ + ioconfig.byte = 0x00; /* All I/O to output mode */ + error = i2c_smbus_xfer(nforce2_smbus, 0x18, 0, I2C_SMBUS_WRITE, 0x03, + I2C_SMBUS_BYTE_DATA, &ioconfig); + if (error) { + dev_err(&nforce2_smbus->dev, "PCA9556 configuration failed\n"); + error = -EIO; + goto ERROR0; + } + + /* Unregister physical bus */ + i2c_del_adapter(nforce2_smbus); + + printk(KERN_INFO "Enabling SMBus multiplexing for Tyan S4985\n"); + /* Define the 5 virtual adapters and algorithms structures */ + s4985_adapter = kcalloc(5, sizeof(struct i2c_adapter), GFP_KERNEL); + if (!s4985_adapter) { + error = -ENOMEM; + goto ERROR1; + } + s4985_algo = kcalloc(5, sizeof(struct i2c_algorithm), GFP_KERNEL); + if (!s4985_algo) { + error = -ENOMEM; + goto ERROR2; + } + + /* Fill in the new structures */ + s4985_algo[0] = *(nforce2_smbus->algo); + s4985_algo[0].smbus_xfer = nforce2_access_virt0; + s4985_adapter[0] = *nforce2_smbus; + s4985_adapter[0].algo = s4985_algo; + s4985_adapter[0].dev.parent = nforce2_smbus->dev.parent; + for (i = 1; i < 5; i++) { + s4985_algo[i] = *(nforce2_smbus->algo); + s4985_adapter[i] = *nforce2_smbus; + snprintf(s4985_adapter[i].name, sizeof(s4985_adapter[i].name), + "SMBus nForce2 adapter (CPU%d)", i - 1); + s4985_adapter[i].algo = s4985_algo + i; + s4985_adapter[i].dev.parent = nforce2_smbus->dev.parent; + } + s4985_algo[1].smbus_xfer = nforce2_access_virt1; + s4985_algo[2].smbus_xfer = nforce2_access_virt2; + s4985_algo[3].smbus_xfer = nforce2_access_virt3; + s4985_algo[4].smbus_xfer = nforce2_access_virt4; + + /* Register virtual adapters */ + for (i = 0; i < 5; i++) { + error = i2c_add_adapter(s4985_adapter + i); + if (error) { + printk(KERN_ERR "i2c-nforce2-s4985: " + "Virtual adapter %d registration " + "failed, module not inserted\n", i); + for (i--; i >= 0; i--) + i2c_del_adapter(s4985_adapter + i); + goto ERROR3; + } + } + + return 0; + +ERROR3: + kfree(s4985_algo); + s4985_algo = NULL; +ERROR2: + kfree(s4985_adapter); + s4985_adapter = NULL; +ERROR1: + /* Restore physical bus */ + i2c_add_adapter(nforce2_smbus); +ERROR0: + return error; +} + +static void __exit nforce2_s4985_exit(void) +{ + if (s4985_adapter) { + int i; + + for (i = 0; i < 5; i++) + i2c_del_adapter(s4985_adapter+i); + kfree(s4985_adapter); + s4985_adapter = NULL; + } + kfree(s4985_algo); + s4985_algo = NULL; + + /* Restore physical bus */ + if (i2c_add_adapter(nforce2_smbus)) + printk(KERN_ERR "i2c-nforce2-s4985: " + "Physical bus restoration failed\n"); +} + +MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>"); +MODULE_DESCRIPTION("S4985 SMBus multiplexing"); +MODULE_LICENSE("GPL"); + +module_init(nforce2_s4985_init); +module_exit(nforce2_s4985_exit); diff --git a/drivers/i2c/busses/i2c-nforce2.c b/drivers/i2c/busses/i2c-nforce2.c new file mode 100644 index 000000000..38d203d93 --- /dev/null +++ b/drivers/i2c/busses/i2c-nforce2.c @@ -0,0 +1,442 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + SMBus driver for nVidia nForce2 MCP + + Added nForce3 Pro 150 Thomas Leibold <thomas@plx.com>, + Ported to 2.5 Patrick Dreker <patrick@dreker.de>, + Copyright (c) 2003 Hans-Frieder Vogt <hfvogt@arcor.de>, + Based on + SMBus 2.0 driver for AMD-8111 IO-Hub + Copyright (c) 2002 Vojtech Pavlik + +*/ + +/* + SUPPORTED DEVICES PCI ID + nForce2 MCP 0064 + nForce2 Ultra 400 MCP 0084 + nForce3 Pro150 MCP 00D4 + nForce3 250Gb MCP 00E4 + nForce4 MCP 0052 + nForce4 MCP-04 0034 + nForce MCP51 0264 + nForce MCP55 0368 + nForce MCP61 03EB + nForce MCP65 0446 + nForce MCP67 0542 + nForce MCP73 07D8 + nForce MCP78S 0752 + nForce MCP79 0AA2 + + This driver supports the 2 SMBuses that are included in the MCP of the + nForce2/3/4/5xx chipsets. +*/ + +/* Note: we assume there can only be one nForce2, with two SMBus interfaces */ + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/stddef.h> +#include <linux/ioport.h> +#include <linux/i2c.h> +#include <linux/delay.h> +#include <linux/dmi.h> +#include <linux/acpi.h> +#include <linux/slab.h> +#include <linux/io.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Hans-Frieder Vogt <hfvogt@gmx.net>"); +MODULE_DESCRIPTION("nForce2/3/4/5xx SMBus driver"); + + +struct nforce2_smbus { + struct i2c_adapter adapter; + int base; + int size; + int blockops; + int can_abort; +}; + + +/* + * nVidia nForce2 SMBus control register definitions + * (Newer incarnations use standard BARs 4 and 5 instead) + */ +#define NFORCE_PCI_SMB1 0x50 +#define NFORCE_PCI_SMB2 0x54 + + +/* + * ACPI 2.0 chapter 13 SMBus 2.0 EC register model + */ +#define NVIDIA_SMB_PRTCL (smbus->base + 0x00) /* protocol, PEC */ +#define NVIDIA_SMB_STS (smbus->base + 0x01) /* status */ +#define NVIDIA_SMB_ADDR (smbus->base + 0x02) /* address */ +#define NVIDIA_SMB_CMD (smbus->base + 0x03) /* command */ +#define NVIDIA_SMB_DATA (smbus->base + 0x04) /* 32 data registers */ +#define NVIDIA_SMB_BCNT (smbus->base + 0x24) /* number of data + bytes */ +#define NVIDIA_SMB_STATUS_ABRT (smbus->base + 0x3c) /* register used to + check the status of + the abort command */ +#define NVIDIA_SMB_CTRL (smbus->base + 0x3e) /* control register */ + +#define NVIDIA_SMB_STATUS_ABRT_STS 0x01 /* Bit to notify that + abort succeeded */ +#define NVIDIA_SMB_CTRL_ABORT 0x20 +#define NVIDIA_SMB_STS_DONE 0x80 +#define NVIDIA_SMB_STS_ALRM 0x40 +#define NVIDIA_SMB_STS_RES 0x20 +#define NVIDIA_SMB_STS_STATUS 0x1f + +#define NVIDIA_SMB_PRTCL_WRITE 0x00 +#define NVIDIA_SMB_PRTCL_READ 0x01 +#define NVIDIA_SMB_PRTCL_QUICK 0x02 +#define NVIDIA_SMB_PRTCL_BYTE 0x04 +#define NVIDIA_SMB_PRTCL_BYTE_DATA 0x06 +#define NVIDIA_SMB_PRTCL_WORD_DATA 0x08 +#define NVIDIA_SMB_PRTCL_BLOCK_DATA 0x0a +#define NVIDIA_SMB_PRTCL_PEC 0x80 + +/* Misc definitions */ +#define MAX_TIMEOUT 100 + +/* We disable the second SMBus channel on these boards */ +static const struct dmi_system_id nforce2_dmi_blacklist2[] = { + { + .ident = "DFI Lanparty NF4 Expert", + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "DFI Corp,LTD"), + DMI_MATCH(DMI_BOARD_NAME, "LP UT NF4 Expert"), + }, + }, + { } +}; + +static struct pci_driver nforce2_driver; + +/* For multiplexing support, we need a global reference to the 1st + SMBus channel */ +#if IS_ENABLED(CONFIG_I2C_NFORCE2_S4985) +struct i2c_adapter *nforce2_smbus; +EXPORT_SYMBOL_GPL(nforce2_smbus); + +static void nforce2_set_reference(struct i2c_adapter *adap) +{ + nforce2_smbus = adap; +} +#else +static inline void nforce2_set_reference(struct i2c_adapter *adap) { } +#endif + +static void nforce2_abort(struct i2c_adapter *adap) +{ + struct nforce2_smbus *smbus = adap->algo_data; + int timeout = 0; + unsigned char temp; + + dev_dbg(&adap->dev, "Aborting current transaction\n"); + + outb_p(NVIDIA_SMB_CTRL_ABORT, NVIDIA_SMB_CTRL); + do { + msleep(1); + temp = inb_p(NVIDIA_SMB_STATUS_ABRT); + } while (!(temp & NVIDIA_SMB_STATUS_ABRT_STS) && + (timeout++ < MAX_TIMEOUT)); + if (!(temp & NVIDIA_SMB_STATUS_ABRT_STS)) + dev_err(&adap->dev, "Can't reset the smbus\n"); + outb_p(NVIDIA_SMB_STATUS_ABRT_STS, NVIDIA_SMB_STATUS_ABRT); +} + +static int nforce2_check_status(struct i2c_adapter *adap) +{ + struct nforce2_smbus *smbus = adap->algo_data; + int timeout = 0; + unsigned char temp; + + do { + msleep(1); + temp = inb_p(NVIDIA_SMB_STS); + } while ((!temp) && (timeout++ < MAX_TIMEOUT)); + + if (timeout > MAX_TIMEOUT) { + dev_dbg(&adap->dev, "SMBus Timeout!\n"); + if (smbus->can_abort) + nforce2_abort(adap); + return -ETIMEDOUT; + } + if (!(temp & NVIDIA_SMB_STS_DONE) || (temp & NVIDIA_SMB_STS_STATUS)) { + dev_dbg(&adap->dev, "Transaction failed (0x%02x)!\n", temp); + return -EIO; + } + return 0; +} + +/* Return negative errno on error */ +static s32 nforce2_access(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data *data) +{ + struct nforce2_smbus *smbus = adap->algo_data; + unsigned char protocol, pec; + u8 len; + int i, status; + + protocol = (read_write == I2C_SMBUS_READ) ? NVIDIA_SMB_PRTCL_READ : + NVIDIA_SMB_PRTCL_WRITE; + pec = (flags & I2C_CLIENT_PEC) ? NVIDIA_SMB_PRTCL_PEC : 0; + + switch (size) { + case I2C_SMBUS_QUICK: + protocol |= NVIDIA_SMB_PRTCL_QUICK; + read_write = I2C_SMBUS_WRITE; + break; + + case I2C_SMBUS_BYTE: + if (read_write == I2C_SMBUS_WRITE) + outb_p(command, NVIDIA_SMB_CMD); + protocol |= NVIDIA_SMB_PRTCL_BYTE; + break; + + case I2C_SMBUS_BYTE_DATA: + outb_p(command, NVIDIA_SMB_CMD); + if (read_write == I2C_SMBUS_WRITE) + outb_p(data->byte, NVIDIA_SMB_DATA); + protocol |= NVIDIA_SMB_PRTCL_BYTE_DATA; + break; + + case I2C_SMBUS_WORD_DATA: + outb_p(command, NVIDIA_SMB_CMD); + if (read_write == I2C_SMBUS_WRITE) { + outb_p(data->word, NVIDIA_SMB_DATA); + outb_p(data->word >> 8, NVIDIA_SMB_DATA + 1); + } + protocol |= NVIDIA_SMB_PRTCL_WORD_DATA | pec; + break; + + case I2C_SMBUS_BLOCK_DATA: + outb_p(command, NVIDIA_SMB_CMD); + if (read_write == I2C_SMBUS_WRITE) { + len = data->block[0]; + if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX)) { + dev_err(&adap->dev, + "Transaction failed (requested block size: %d)\n", + len); + return -EINVAL; + } + outb_p(len, NVIDIA_SMB_BCNT); + for (i = 0; i < I2C_SMBUS_BLOCK_MAX; i++) + outb_p(data->block[i + 1], + NVIDIA_SMB_DATA + i); + } + protocol |= NVIDIA_SMB_PRTCL_BLOCK_DATA | pec; + break; + + default: + dev_err(&adap->dev, "Unsupported transaction %d\n", size); + return -EOPNOTSUPP; + } + + outb_p((addr & 0x7f) << 1, NVIDIA_SMB_ADDR); + outb_p(protocol, NVIDIA_SMB_PRTCL); + + status = nforce2_check_status(adap); + if (status) + return status; + + if (read_write == I2C_SMBUS_WRITE) + return 0; + + switch (size) { + case I2C_SMBUS_BYTE: + case I2C_SMBUS_BYTE_DATA: + data->byte = inb_p(NVIDIA_SMB_DATA); + break; + + case I2C_SMBUS_WORD_DATA: + data->word = inb_p(NVIDIA_SMB_DATA) | + (inb_p(NVIDIA_SMB_DATA + 1) << 8); + break; + + case I2C_SMBUS_BLOCK_DATA: + len = inb_p(NVIDIA_SMB_BCNT); + if ((len <= 0) || (len > I2C_SMBUS_BLOCK_MAX)) { + dev_err(&adap->dev, + "Transaction failed (received block size: 0x%02x)\n", + len); + return -EPROTO; + } + for (i = 0; i < len; i++) + data->block[i + 1] = inb_p(NVIDIA_SMB_DATA + i); + data->block[0] = len; + break; + } + + return 0; +} + + +static u32 nforce2_func(struct i2c_adapter *adapter) +{ + /* other functionality might be possible, but is not tested */ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_PEC | + (((struct nforce2_smbus *)adapter->algo_data)->blockops ? + I2C_FUNC_SMBUS_BLOCK_DATA : 0); +} + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = nforce2_access, + .functionality = nforce2_func, +}; + + +static const struct pci_device_id nforce2_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2S_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE3_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE3S_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE4_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP04_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP61_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP65_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP67_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP73_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP78S_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP79_SMBUS) }, + { 0 } +}; + +MODULE_DEVICE_TABLE(pci, nforce2_ids); + + +static int nforce2_probe_smb(struct pci_dev *dev, int bar, int alt_reg, + struct nforce2_smbus *smbus, const char *name) +{ + int error; + + smbus->base = pci_resource_start(dev, bar); + if (smbus->base) { + smbus->size = pci_resource_len(dev, bar); + } else { + /* Older incarnations of the device used non-standard BARs */ + u16 iobase; + + error = pci_read_config_word(dev, alt_reg, &iobase); + if (error != PCIBIOS_SUCCESSFUL) { + dev_err(&dev->dev, "Error reading PCI config for %s\n", + name); + return -EIO; + } + + smbus->base = iobase & PCI_BASE_ADDRESS_IO_MASK; + smbus->size = 64; + } + + error = acpi_check_region(smbus->base, smbus->size, + nforce2_driver.name); + if (error) + return error; + + if (!request_region(smbus->base, smbus->size, nforce2_driver.name)) { + dev_err(&smbus->adapter.dev, "Error requesting region %02x .. %02X for %s\n", + smbus->base, smbus->base+smbus->size-1, name); + return -EBUSY; + } + smbus->adapter.owner = THIS_MODULE; + smbus->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + smbus->adapter.algo = &smbus_algorithm; + smbus->adapter.algo_data = smbus; + smbus->adapter.dev.parent = &dev->dev; + snprintf(smbus->adapter.name, sizeof(smbus->adapter.name), + "SMBus nForce2 adapter at %04x", smbus->base); + + error = i2c_add_adapter(&smbus->adapter); + if (error) { + release_region(smbus->base, smbus->size); + return error; + } + dev_info(&smbus->adapter.dev, "nForce2 SMBus adapter at %#x\n", + smbus->base); + return 0; +} + + +static int nforce2_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + struct nforce2_smbus *smbuses; + int res1, res2; + + /* we support 2 SMBus adapters */ + smbuses = kcalloc(2, sizeof(struct nforce2_smbus), GFP_KERNEL); + if (!smbuses) + return -ENOMEM; + pci_set_drvdata(dev, smbuses); + + switch (dev->device) { + case PCI_DEVICE_ID_NVIDIA_NFORCE2_SMBUS: + case PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SMBUS: + case PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SMBUS: + smbuses[0].blockops = 1; + smbuses[1].blockops = 1; + smbuses[0].can_abort = 1; + smbuses[1].can_abort = 1; + } + + /* SMBus adapter 1 */ + res1 = nforce2_probe_smb(dev, 4, NFORCE_PCI_SMB1, &smbuses[0], "SMB1"); + if (res1 < 0) + smbuses[0].base = 0; /* to have a check value */ + + /* SMBus adapter 2 */ + if (dmi_check_system(nforce2_dmi_blacklist2)) { + dev_err(&dev->dev, "Disabling SMB2 for safety reasons.\n"); + res2 = -EPERM; + smbuses[1].base = 0; + } else { + res2 = nforce2_probe_smb(dev, 5, NFORCE_PCI_SMB2, &smbuses[1], + "SMB2"); + if (res2 < 0) + smbuses[1].base = 0; /* to have a check value */ + } + + if ((res1 < 0) && (res2 < 0)) { + /* we did not find even one of the SMBuses, so we give up */ + kfree(smbuses); + return -ENODEV; + } + + nforce2_set_reference(&smbuses[0].adapter); + return 0; +} + + +static void nforce2_remove(struct pci_dev *dev) +{ + struct nforce2_smbus *smbuses = pci_get_drvdata(dev); + + nforce2_set_reference(NULL); + if (smbuses[0].base) { + i2c_del_adapter(&smbuses[0].adapter); + release_region(smbuses[0].base, smbuses[0].size); + } + if (smbuses[1].base) { + i2c_del_adapter(&smbuses[1].adapter); + release_region(smbuses[1].base, smbuses[1].size); + } + kfree(smbuses); +} + +static struct pci_driver nforce2_driver = { + .name = "nForce2_smbus", + .id_table = nforce2_ids, + .probe = nforce2_probe, + .remove = nforce2_remove, +}; + +module_pci_driver(nforce2_driver); diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c new file mode 100644 index 000000000..b10574d42 --- /dev/null +++ b/drivers/i2c/busses/i2c-nomadik.c @@ -0,0 +1,1098 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2009 ST-Ericsson SA + * Copyright (C) 2009 STMicroelectronics + * + * I2C master mode controller driver, used in Nomadik 8815 + * and Ux500 platforms. + * + * Author: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> + * Author: Sachin Verma <sachin.verma@st.com> + */ +#include <linux/init.h> +#include <linux/module.h> +#include <linux/amba/bus.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/i2c.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/pm_runtime.h> +#include <linux/of.h> +#include <linux/pinctrl/consumer.h> + +#define DRIVER_NAME "nmk-i2c" + +/* I2C Controller register offsets */ +#define I2C_CR (0x000) +#define I2C_SCR (0x004) +#define I2C_HSMCR (0x008) +#define I2C_MCR (0x00C) +#define I2C_TFR (0x010) +#define I2C_SR (0x014) +#define I2C_RFR (0x018) +#define I2C_TFTR (0x01C) +#define I2C_RFTR (0x020) +#define I2C_DMAR (0x024) +#define I2C_BRCR (0x028) +#define I2C_IMSCR (0x02C) +#define I2C_RISR (0x030) +#define I2C_MISR (0x034) +#define I2C_ICR (0x038) + +/* Control registers */ +#define I2C_CR_PE (0x1 << 0) /* Peripheral Enable */ +#define I2C_CR_OM (0x3 << 1) /* Operating mode */ +#define I2C_CR_SAM (0x1 << 3) /* Slave addressing mode */ +#define I2C_CR_SM (0x3 << 4) /* Speed mode */ +#define I2C_CR_SGCM (0x1 << 6) /* Slave general call mode */ +#define I2C_CR_FTX (0x1 << 7) /* Flush Transmit */ +#define I2C_CR_FRX (0x1 << 8) /* Flush Receive */ +#define I2C_CR_DMA_TX_EN (0x1 << 9) /* DMA Tx enable */ +#define I2C_CR_DMA_RX_EN (0x1 << 10) /* DMA Rx Enable */ +#define I2C_CR_DMA_SLE (0x1 << 11) /* DMA sync. logic enable */ +#define I2C_CR_LM (0x1 << 12) /* Loopback mode */ +#define I2C_CR_FON (0x3 << 13) /* Filtering on */ +#define I2C_CR_FS (0x3 << 15) /* Force stop enable */ + +/* Master controller (MCR) register */ +#define I2C_MCR_OP (0x1 << 0) /* Operation */ +#define I2C_MCR_A7 (0x7f << 1) /* 7-bit address */ +#define I2C_MCR_EA10 (0x7 << 8) /* 10-bit Extended address */ +#define I2C_MCR_SB (0x1 << 11) /* Extended address */ +#define I2C_MCR_AM (0x3 << 12) /* Address type */ +#define I2C_MCR_STOP (0x1 << 14) /* Stop condition */ +#define I2C_MCR_LENGTH (0x7ff << 15) /* Transaction length */ + +/* Status register (SR) */ +#define I2C_SR_OP (0x3 << 0) /* Operation */ +#define I2C_SR_STATUS (0x3 << 2) /* controller status */ +#define I2C_SR_CAUSE (0x7 << 4) /* Abort cause */ +#define I2C_SR_TYPE (0x3 << 7) /* Receive type */ +#define I2C_SR_LENGTH (0x7ff << 9) /* Transfer length */ + +/* Interrupt mask set/clear (IMSCR) bits */ +#define I2C_IT_TXFE (0x1 << 0) +#define I2C_IT_TXFNE (0x1 << 1) +#define I2C_IT_TXFF (0x1 << 2) +#define I2C_IT_TXFOVR (0x1 << 3) +#define I2C_IT_RXFE (0x1 << 4) +#define I2C_IT_RXFNF (0x1 << 5) +#define I2C_IT_RXFF (0x1 << 6) +#define I2C_IT_RFSR (0x1 << 16) +#define I2C_IT_RFSE (0x1 << 17) +#define I2C_IT_WTSR (0x1 << 18) +#define I2C_IT_MTD (0x1 << 19) +#define I2C_IT_STD (0x1 << 20) +#define I2C_IT_MAL (0x1 << 24) +#define I2C_IT_BERR (0x1 << 25) +#define I2C_IT_MTDWS (0x1 << 28) + +#define GEN_MASK(val, mask, sb) (((val) << (sb)) & (mask)) + +/* some bits in ICR are reserved */ +#define I2C_CLEAR_ALL_INTS 0x131f007f + +/* first three msb bits are reserved */ +#define IRQ_MASK(mask) (mask & 0x1fffffff) + +/* maximum threshold value */ +#define MAX_I2C_FIFO_THRESHOLD 15 + +enum i2c_freq_mode { + I2C_FREQ_MODE_STANDARD, /* up to 100 Kb/s */ + I2C_FREQ_MODE_FAST, /* up to 400 Kb/s */ + I2C_FREQ_MODE_HIGH_SPEED, /* up to 3.4 Mb/s */ + I2C_FREQ_MODE_FAST_PLUS, /* up to 1 Mb/s */ +}; + +/** + * struct i2c_vendor_data - per-vendor variations + * @has_mtdws: variant has the MTDWS bit + * @fifodepth: variant FIFO depth + */ +struct i2c_vendor_data { + bool has_mtdws; + u32 fifodepth; +}; + +enum i2c_status { + I2C_NOP, + I2C_ON_GOING, + I2C_OK, + I2C_ABORT +}; + +/* operation */ +enum i2c_operation { + I2C_NO_OPERATION = 0xff, + I2C_WRITE = 0x00, + I2C_READ = 0x01 +}; + +/** + * struct i2c_nmk_client - client specific data + * @slave_adr: 7-bit slave address + * @count: no. bytes to be transferred + * @buffer: client data buffer + * @xfer_bytes: bytes transferred till now + * @operation: current I2C operation + */ +struct i2c_nmk_client { + unsigned short slave_adr; + unsigned long count; + unsigned char *buffer; + unsigned long xfer_bytes; + enum i2c_operation operation; +}; + +/** + * struct nmk_i2c_dev - private data structure of the controller. + * @vendor: vendor data for this variant. + * @adev: parent amba device. + * @adap: corresponding I2C adapter. + * @irq: interrupt line for the controller. + * @virtbase: virtual io memory area. + * @clk: hardware i2c block clock. + * @cli: holder of client specific data. + * @clk_freq: clock frequency for the operation mode + * @tft: Tx FIFO Threshold in bytes + * @rft: Rx FIFO Threshold in bytes + * @timeout: Slave response timeout (ms) + * @sm: speed mode + * @stop: stop condition. + * @xfer_complete: acknowledge completion for a I2C message. + * @result: controller propogated result. + */ +struct nmk_i2c_dev { + struct i2c_vendor_data *vendor; + struct amba_device *adev; + struct i2c_adapter adap; + int irq; + void __iomem *virtbase; + struct clk *clk; + struct i2c_nmk_client cli; + u32 clk_freq; + unsigned char tft; + unsigned char rft; + int timeout; + enum i2c_freq_mode sm; + int stop; + struct completion xfer_complete; + int result; +}; + +/* controller's abort causes */ +static const char *abort_causes[] = { + "no ack received after address transmission", + "no ack received during data phase", + "ack received after xmission of master code", + "master lost arbitration", + "slave restarts", + "slave reset", + "overflow, maxsize is 2047 bytes", +}; + +static inline void i2c_set_bit(void __iomem *reg, u32 mask) +{ + writel(readl(reg) | mask, reg); +} + +static inline void i2c_clr_bit(void __iomem *reg, u32 mask) +{ + writel(readl(reg) & ~mask, reg); +} + +/** + * flush_i2c_fifo() - This function flushes the I2C FIFO + * @dev: private data of I2C Driver + * + * This function flushes the I2C Tx and Rx FIFOs. It returns + * 0 on successful flushing of FIFO + */ +static int flush_i2c_fifo(struct nmk_i2c_dev *dev) +{ +#define LOOP_ATTEMPTS 10 + int i; + unsigned long timeout; + + /* + * flush the transmit and receive FIFO. The flushing + * operation takes several cycles before to be completed. + * On the completion, the I2C internal logic clears these + * bits, until then no one must access Tx, Rx FIFO and + * should poll on these bits waiting for the completion. + */ + writel((I2C_CR_FTX | I2C_CR_FRX), dev->virtbase + I2C_CR); + + for (i = 0; i < LOOP_ATTEMPTS; i++) { + timeout = jiffies + dev->adap.timeout; + + while (!time_after(jiffies, timeout)) { + if ((readl(dev->virtbase + I2C_CR) & + (I2C_CR_FTX | I2C_CR_FRX)) == 0) + return 0; + } + } + + dev_err(&dev->adev->dev, + "flushing operation timed out giving up after %d attempts", + LOOP_ATTEMPTS); + + return -ETIMEDOUT; +} + +/** + * disable_all_interrupts() - Disable all interrupts of this I2c Bus + * @dev: private data of I2C Driver + */ +static void disable_all_interrupts(struct nmk_i2c_dev *dev) +{ + u32 mask = IRQ_MASK(0); + writel(mask, dev->virtbase + I2C_IMSCR); +} + +/** + * clear_all_interrupts() - Clear all interrupts of I2C Controller + * @dev: private data of I2C Driver + */ +static void clear_all_interrupts(struct nmk_i2c_dev *dev) +{ + u32 mask; + mask = IRQ_MASK(I2C_CLEAR_ALL_INTS); + writel(mask, dev->virtbase + I2C_ICR); +} + +/** + * init_hw() - initialize the I2C hardware + * @dev: private data of I2C Driver + */ +static int init_hw(struct nmk_i2c_dev *dev) +{ + int stat; + + stat = flush_i2c_fifo(dev); + if (stat) + goto exit; + + /* disable the controller */ + i2c_clr_bit(dev->virtbase + I2C_CR, I2C_CR_PE); + + disable_all_interrupts(dev); + + clear_all_interrupts(dev); + + dev->cli.operation = I2C_NO_OPERATION; + +exit: + return stat; +} + +/* enable peripheral, master mode operation */ +#define DEFAULT_I2C_REG_CR ((1 << 1) | I2C_CR_PE) + +/** + * load_i2c_mcr_reg() - load the MCR register + * @dev: private data of controller + * @flags: message flags + */ +static u32 load_i2c_mcr_reg(struct nmk_i2c_dev *dev, u16 flags) +{ + u32 mcr = 0; + unsigned short slave_adr_3msb_bits; + + mcr |= GEN_MASK(dev->cli.slave_adr, I2C_MCR_A7, 1); + + if (unlikely(flags & I2C_M_TEN)) { + /* 10-bit address transaction */ + mcr |= GEN_MASK(2, I2C_MCR_AM, 12); + /* + * Get the top 3 bits. + * EA10 represents extended address in MCR. This includes + * the extension (MSB bits) of the 7 bit address loaded + * in A7 + */ + slave_adr_3msb_bits = (dev->cli.slave_adr >> 7) & 0x7; + + mcr |= GEN_MASK(slave_adr_3msb_bits, I2C_MCR_EA10, 8); + } else { + /* 7-bit address transaction */ + mcr |= GEN_MASK(1, I2C_MCR_AM, 12); + } + + /* start byte procedure not applied */ + mcr |= GEN_MASK(0, I2C_MCR_SB, 11); + + /* check the operation, master read/write? */ + if (dev->cli.operation == I2C_WRITE) + mcr |= GEN_MASK(I2C_WRITE, I2C_MCR_OP, 0); + else + mcr |= GEN_MASK(I2C_READ, I2C_MCR_OP, 0); + + /* stop or repeated start? */ + if (dev->stop) + mcr |= GEN_MASK(1, I2C_MCR_STOP, 14); + else + mcr &= ~(GEN_MASK(1, I2C_MCR_STOP, 14)); + + mcr |= GEN_MASK(dev->cli.count, I2C_MCR_LENGTH, 15); + + return mcr; +} + +/** + * setup_i2c_controller() - setup the controller + * @dev: private data of controller + */ +static void setup_i2c_controller(struct nmk_i2c_dev *dev) +{ + u32 brcr1, brcr2; + u32 i2c_clk, div; + u32 ns; + u16 slsu; + + writel(0x0, dev->virtbase + I2C_CR); + writel(0x0, dev->virtbase + I2C_HSMCR); + writel(0x0, dev->virtbase + I2C_TFTR); + writel(0x0, dev->virtbase + I2C_RFTR); + writel(0x0, dev->virtbase + I2C_DMAR); + + i2c_clk = clk_get_rate(dev->clk); + + /* + * set the slsu: + * + * slsu defines the data setup time after SCL clock + * stretching in terms of i2c clk cycles + 1 (zero means + * "wait one cycle"), the needed setup time for the three + * modes are 250ns, 100ns, 10ns respectively. + * + * As the time for one cycle T in nanoseconds is + * T = (1/f) * 1000000000 => + * slsu = cycles / (1000000000 / f) + 1 + */ + ns = DIV_ROUND_UP_ULL(1000000000ULL, i2c_clk); + switch (dev->sm) { + case I2C_FREQ_MODE_FAST: + case I2C_FREQ_MODE_FAST_PLUS: + slsu = DIV_ROUND_UP(100, ns); /* Fast */ + break; + case I2C_FREQ_MODE_HIGH_SPEED: + slsu = DIV_ROUND_UP(10, ns); /* High */ + break; + case I2C_FREQ_MODE_STANDARD: + default: + slsu = DIV_ROUND_UP(250, ns); /* Standard */ + break; + } + slsu += 1; + + dev_dbg(&dev->adev->dev, "calculated SLSU = %04x\n", slsu); + writel(slsu << 16, dev->virtbase + I2C_SCR); + + /* + * The spec says, in case of std. mode the divider is + * 2 whereas it is 3 for fast and fastplus mode of + * operation. TODO - high speed support. + */ + div = (dev->clk_freq > I2C_MAX_STANDARD_MODE_FREQ) ? 3 : 2; + + /* + * generate the mask for baud rate counters. The controller + * has two baud rate counters. One is used for High speed + * operation, and the other is for std, fast mode, fast mode + * plus operation. Currently we do not supprt high speed mode + * so set brcr1 to 0. + */ + brcr1 = 0 << 16; + brcr2 = (i2c_clk/(dev->clk_freq * div)) & 0xffff; + + /* set the baud rate counter register */ + writel((brcr1 | brcr2), dev->virtbase + I2C_BRCR); + + /* + * set the speed mode. Currently we support + * only standard and fast mode of operation + * TODO - support for fast mode plus (up to 1Mb/s) + * and high speed (up to 3.4 Mb/s) + */ + if (dev->sm > I2C_FREQ_MODE_FAST) { + dev_err(&dev->adev->dev, + "do not support this mode defaulting to std. mode\n"); + brcr2 = i2c_clk / (I2C_MAX_STANDARD_MODE_FREQ * 2) & 0xffff; + writel((brcr1 | brcr2), dev->virtbase + I2C_BRCR); + writel(I2C_FREQ_MODE_STANDARD << 4, + dev->virtbase + I2C_CR); + } + writel(dev->sm << 4, dev->virtbase + I2C_CR); + + /* set the Tx and Rx FIFO threshold */ + writel(dev->tft, dev->virtbase + I2C_TFTR); + writel(dev->rft, dev->virtbase + I2C_RFTR); +} + +/** + * read_i2c() - Read from I2C client device + * @dev: private data of I2C Driver + * @flags: message flags + * + * This function reads from i2c client device when controller is in + * master mode. There is a completion timeout. If there is no transfer + * before timeout error is returned. + */ +static int read_i2c(struct nmk_i2c_dev *dev, u16 flags) +{ + int status = 0; + u32 mcr, irq_mask; + unsigned long timeout; + + mcr = load_i2c_mcr_reg(dev, flags); + writel(mcr, dev->virtbase + I2C_MCR); + + /* load the current CR value */ + writel(readl(dev->virtbase + I2C_CR) | DEFAULT_I2C_REG_CR, + dev->virtbase + I2C_CR); + + /* enable the controller */ + i2c_set_bit(dev->virtbase + I2C_CR, I2C_CR_PE); + + init_completion(&dev->xfer_complete); + + /* enable interrupts by setting the mask */ + irq_mask = (I2C_IT_RXFNF | I2C_IT_RXFF | + I2C_IT_MAL | I2C_IT_BERR); + + if (dev->stop || !dev->vendor->has_mtdws) + irq_mask |= I2C_IT_MTD; + else + irq_mask |= I2C_IT_MTDWS; + + irq_mask = I2C_CLEAR_ALL_INTS & IRQ_MASK(irq_mask); + + writel(readl(dev->virtbase + I2C_IMSCR) | irq_mask, + dev->virtbase + I2C_IMSCR); + + timeout = wait_for_completion_timeout( + &dev->xfer_complete, dev->adap.timeout); + + if (timeout == 0) { + /* Controller timed out */ + dev_err(&dev->adev->dev, "read from slave 0x%x timed out\n", + dev->cli.slave_adr); + status = -ETIMEDOUT; + } + return status; +} + +static void fill_tx_fifo(struct nmk_i2c_dev *dev, int no_bytes) +{ + int count; + + for (count = (no_bytes - 2); + (count > 0) && + (dev->cli.count != 0); + count--) { + /* write to the Tx FIFO */ + writeb(*dev->cli.buffer, + dev->virtbase + I2C_TFR); + dev->cli.buffer++; + dev->cli.count--; + dev->cli.xfer_bytes++; + } + +} + +/** + * write_i2c() - Write data to I2C client. + * @dev: private data of I2C Driver + * @flags: message flags + * + * This function writes data to I2C client + */ +static int write_i2c(struct nmk_i2c_dev *dev, u16 flags) +{ + u32 status = 0; + u32 mcr, irq_mask; + unsigned long timeout; + + mcr = load_i2c_mcr_reg(dev, flags); + + writel(mcr, dev->virtbase + I2C_MCR); + + /* load the current CR value */ + writel(readl(dev->virtbase + I2C_CR) | DEFAULT_I2C_REG_CR, + dev->virtbase + I2C_CR); + + /* enable the controller */ + i2c_set_bit(dev->virtbase + I2C_CR, I2C_CR_PE); + + init_completion(&dev->xfer_complete); + + /* enable interrupts by settings the masks */ + irq_mask = (I2C_IT_TXFOVR | I2C_IT_MAL | I2C_IT_BERR); + + /* Fill the TX FIFO with transmit data */ + fill_tx_fifo(dev, MAX_I2C_FIFO_THRESHOLD); + + if (dev->cli.count != 0) + irq_mask |= I2C_IT_TXFNE; + + /* + * check if we want to transfer a single or multiple bytes, if so + * set the MTDWS bit (Master Transaction Done Without Stop) + * to start repeated start operation + */ + if (dev->stop || !dev->vendor->has_mtdws) + irq_mask |= I2C_IT_MTD; + else + irq_mask |= I2C_IT_MTDWS; + + irq_mask = I2C_CLEAR_ALL_INTS & IRQ_MASK(irq_mask); + + writel(readl(dev->virtbase + I2C_IMSCR) | irq_mask, + dev->virtbase + I2C_IMSCR); + + timeout = wait_for_completion_timeout( + &dev->xfer_complete, dev->adap.timeout); + + if (timeout == 0) { + /* Controller timed out */ + dev_err(&dev->adev->dev, "write to slave 0x%x timed out\n", + dev->cli.slave_adr); + status = -ETIMEDOUT; + } + + return status; +} + +/** + * nmk_i2c_xfer_one() - transmit a single I2C message + * @dev: device with a message encoded into it + * @flags: message flags + */ +static int nmk_i2c_xfer_one(struct nmk_i2c_dev *dev, u16 flags) +{ + int status; + + if (flags & I2C_M_RD) { + /* read operation */ + dev->cli.operation = I2C_READ; + status = read_i2c(dev, flags); + } else { + /* write operation */ + dev->cli.operation = I2C_WRITE; + status = write_i2c(dev, flags); + } + + if (status || (dev->result)) { + u32 i2c_sr; + u32 cause; + + i2c_sr = readl(dev->virtbase + I2C_SR); + /* + * Check if the controller I2C operation status + * is set to ABORT(11b). + */ + if (((i2c_sr >> 2) & 0x3) == 0x3) { + /* get the abort cause */ + cause = (i2c_sr >> 4) & 0x7; + dev_err(&dev->adev->dev, "%s\n", + cause >= ARRAY_SIZE(abort_causes) ? + "unknown reason" : + abort_causes[cause]); + } + + (void) init_hw(dev); + + status = status ? status : dev->result; + } + + return status; +} + +/** + * nmk_i2c_xfer() - I2C transfer function used by kernel framework + * @i2c_adap: Adapter pointer to the controller + * @msgs: Pointer to data to be written. + * @num_msgs: Number of messages to be executed + * + * This is the function called by the generic kernel i2c_transfer() + * or i2c_smbus...() API calls. Note that this code is protected by the + * semaphore set in the kernel i2c_transfer() function. + * + * NOTE: + * READ TRANSFER : We impose a restriction of the first message to be the + * index message for any read transaction. + * - a no index is coded as '0', + * - 2byte big endian index is coded as '3' + * !!! msg[0].buf holds the actual index. + * This is compatible with generic messages of smbus emulator + * that send a one byte index. + * eg. a I2C transation to read 2 bytes from index 0 + * idx = 0; + * msg[0].addr = client->addr; + * msg[0].flags = 0x0; + * msg[0].len = 1; + * msg[0].buf = &idx; + * + * msg[1].addr = client->addr; + * msg[1].flags = I2C_M_RD; + * msg[1].len = 2; + * msg[1].buf = rd_buff + * i2c_transfer(adap, msg, 2); + * + * WRITE TRANSFER : The I2C standard interface interprets all data as payload. + * If you want to emulate an SMBUS write transaction put the + * index as first byte(or first and second) in the payload. + * eg. a I2C transation to write 2 bytes from index 1 + * wr_buff[0] = 0x1; + * wr_buff[1] = 0x23; + * wr_buff[2] = 0x46; + * msg[0].flags = 0x0; + * msg[0].len = 3; + * msg[0].buf = wr_buff; + * i2c_transfer(adap, msg, 1); + * + * To read or write a block of data (multiple bytes) using SMBUS emulation + * please use the i2c_smbus_read_i2c_block_data() + * or i2c_smbus_write_i2c_block_data() API + */ +static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap, + struct i2c_msg msgs[], int num_msgs) +{ + int status = 0; + int i; + struct nmk_i2c_dev *dev = i2c_get_adapdata(i2c_adap); + int j; + + pm_runtime_get_sync(&dev->adev->dev); + + /* Attempt three times to send the message queue */ + for (j = 0; j < 3; j++) { + /* setup the i2c controller */ + setup_i2c_controller(dev); + + for (i = 0; i < num_msgs; i++) { + dev->cli.slave_adr = msgs[i].addr; + dev->cli.buffer = msgs[i].buf; + dev->cli.count = msgs[i].len; + dev->stop = (i < (num_msgs - 1)) ? 0 : 1; + dev->result = 0; + + status = nmk_i2c_xfer_one(dev, msgs[i].flags); + if (status != 0) + break; + } + if (status == 0) + break; + } + + pm_runtime_put_sync(&dev->adev->dev); + + /* return the no. messages processed */ + if (status) + return status; + else + return num_msgs; +} + +/** + * disable_interrupts() - disable the interrupts + * @dev: private data of controller + * @irq: interrupt number + */ +static int disable_interrupts(struct nmk_i2c_dev *dev, u32 irq) +{ + irq = IRQ_MASK(irq); + writel(readl(dev->virtbase + I2C_IMSCR) & ~(I2C_CLEAR_ALL_INTS & irq), + dev->virtbase + I2C_IMSCR); + return 0; +} + +/** + * i2c_irq_handler() - interrupt routine + * @irq: interrupt number + * @arg: data passed to the handler + * + * This is the interrupt handler for the i2c driver. Currently + * it handles the major interrupts like Rx & Tx FIFO management + * interrupts, master transaction interrupts, arbitration and + * bus error interrupts. The rest of the interrupts are treated as + * unhandled. + */ +static irqreturn_t i2c_irq_handler(int irq, void *arg) +{ + struct nmk_i2c_dev *dev = arg; + u32 tft, rft; + u32 count; + u32 misr, src; + + /* load Tx FIFO and Rx FIFO threshold values */ + tft = readl(dev->virtbase + I2C_TFTR); + rft = readl(dev->virtbase + I2C_RFTR); + + /* read interrupt status register */ + misr = readl(dev->virtbase + I2C_MISR); + + src = __ffs(misr); + switch ((1 << src)) { + + /* Transmit FIFO nearly empty interrupt */ + case I2C_IT_TXFNE: + { + if (dev->cli.operation == I2C_READ) { + /* + * in read operation why do we care for writing? + * so disable the Transmit FIFO interrupt + */ + disable_interrupts(dev, I2C_IT_TXFNE); + } else { + fill_tx_fifo(dev, (MAX_I2C_FIFO_THRESHOLD - tft)); + /* + * if done, close the transfer by disabling the + * corresponding TXFNE interrupt + */ + if (dev->cli.count == 0) + disable_interrupts(dev, I2C_IT_TXFNE); + } + } + break; + + /* + * Rx FIFO nearly full interrupt. + * This is set when the numer of entries in Rx FIFO is + * greater or equal than the threshold value programmed + * in RFT + */ + case I2C_IT_RXFNF: + for (count = rft; count > 0; count--) { + /* Read the Rx FIFO */ + *dev->cli.buffer = readb(dev->virtbase + I2C_RFR); + dev->cli.buffer++; + } + dev->cli.count -= rft; + dev->cli.xfer_bytes += rft; + break; + + /* Rx FIFO full */ + case I2C_IT_RXFF: + for (count = MAX_I2C_FIFO_THRESHOLD; count > 0; count--) { + *dev->cli.buffer = readb(dev->virtbase + I2C_RFR); + dev->cli.buffer++; + } + dev->cli.count -= MAX_I2C_FIFO_THRESHOLD; + dev->cli.xfer_bytes += MAX_I2C_FIFO_THRESHOLD; + break; + + /* Master Transaction Done with/without stop */ + case I2C_IT_MTD: + case I2C_IT_MTDWS: + if (dev->cli.operation == I2C_READ) { + while (!(readl(dev->virtbase + I2C_RISR) + & I2C_IT_RXFE)) { + if (dev->cli.count == 0) + break; + *dev->cli.buffer = + readb(dev->virtbase + I2C_RFR); + dev->cli.buffer++; + dev->cli.count--; + dev->cli.xfer_bytes++; + } + } + + disable_all_interrupts(dev); + clear_all_interrupts(dev); + + if (dev->cli.count) { + dev->result = -EIO; + dev_err(&dev->adev->dev, + "%lu bytes still remain to be xfered\n", + dev->cli.count); + (void) init_hw(dev); + } + complete(&dev->xfer_complete); + + break; + + /* Master Arbitration lost interrupt */ + case I2C_IT_MAL: + dev->result = -EIO; + (void) init_hw(dev); + + i2c_set_bit(dev->virtbase + I2C_ICR, I2C_IT_MAL); + complete(&dev->xfer_complete); + + break; + + /* + * Bus Error interrupt. + * This happens when an unexpected start/stop condition occurs + * during the transaction. + */ + case I2C_IT_BERR: + dev->result = -EIO; + /* get the status */ + if (((readl(dev->virtbase + I2C_SR) >> 2) & 0x3) == I2C_ABORT) + (void) init_hw(dev); + + i2c_set_bit(dev->virtbase + I2C_ICR, I2C_IT_BERR); + complete(&dev->xfer_complete); + + break; + + /* + * Tx FIFO overrun interrupt. + * This is set when a write operation in Tx FIFO is performed and + * the Tx FIFO is full. + */ + case I2C_IT_TXFOVR: + dev->result = -EIO; + (void) init_hw(dev); + + dev_err(&dev->adev->dev, "Tx Fifo Over run\n"); + complete(&dev->xfer_complete); + + break; + + /* unhandled interrupts by this driver - TODO*/ + case I2C_IT_TXFE: + case I2C_IT_TXFF: + case I2C_IT_RXFE: + case I2C_IT_RFSR: + case I2C_IT_RFSE: + case I2C_IT_WTSR: + case I2C_IT_STD: + dev_err(&dev->adev->dev, "unhandled Interrupt\n"); + break; + default: + dev_err(&dev->adev->dev, "spurious Interrupt..\n"); + break; + } + + return IRQ_HANDLED; +} + +static int nmk_i2c_suspend_late(struct device *dev) +{ + int ret; + + ret = pm_runtime_force_suspend(dev); + if (ret) + return ret; + + pinctrl_pm_select_sleep_state(dev); + return 0; +} + +static int nmk_i2c_resume_early(struct device *dev) +{ + return pm_runtime_force_resume(dev); +} + +static int nmk_i2c_runtime_suspend(struct device *dev) +{ + struct amba_device *adev = to_amba_device(dev); + struct nmk_i2c_dev *nmk_i2c = amba_get_drvdata(adev); + + clk_disable_unprepare(nmk_i2c->clk); + pinctrl_pm_select_idle_state(dev); + return 0; +} + +static int nmk_i2c_runtime_resume(struct device *dev) +{ + struct amba_device *adev = to_amba_device(dev); + struct nmk_i2c_dev *nmk_i2c = amba_get_drvdata(adev); + int ret; + + ret = clk_prepare_enable(nmk_i2c->clk); + if (ret) { + dev_err(dev, "can't prepare_enable clock\n"); + return ret; + } + + pinctrl_pm_select_default_state(dev); + + ret = init_hw(nmk_i2c); + if (ret) { + clk_disable_unprepare(nmk_i2c->clk); + pinctrl_pm_select_idle_state(dev); + } + + return ret; +} + +static const struct dev_pm_ops nmk_i2c_pm = { + LATE_SYSTEM_SLEEP_PM_OPS(nmk_i2c_suspend_late, nmk_i2c_resume_early) + RUNTIME_PM_OPS(nmk_i2c_runtime_suspend, nmk_i2c_runtime_resume, NULL) +}; + +static unsigned int nmk_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR; +} + +static const struct i2c_algorithm nmk_i2c_algo = { + .master_xfer = nmk_i2c_xfer, + .functionality = nmk_i2c_functionality +}; + +static void nmk_i2c_of_probe(struct device_node *np, + struct nmk_i2c_dev *nmk) +{ + /* Default to 100 kHz if no frequency is given in the node */ + if (of_property_read_u32(np, "clock-frequency", &nmk->clk_freq)) + nmk->clk_freq = I2C_MAX_STANDARD_MODE_FREQ; + + /* This driver only supports 'standard' and 'fast' modes of operation. */ + if (nmk->clk_freq <= I2C_MAX_STANDARD_MODE_FREQ) + nmk->sm = I2C_FREQ_MODE_STANDARD; + else + nmk->sm = I2C_FREQ_MODE_FAST; + nmk->tft = 1; /* Tx FIFO threshold */ + nmk->rft = 8; /* Rx FIFO threshold */ + nmk->timeout = 200; /* Slave response timeout(ms) */ +} + +static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id) +{ + int ret = 0; + struct device_node *np = adev->dev.of_node; + struct nmk_i2c_dev *dev; + struct i2c_adapter *adap; + struct i2c_vendor_data *vendor = id->data; + u32 max_fifo_threshold = (vendor->fifodepth / 2) - 1; + + dev = devm_kzalloc(&adev->dev, sizeof(*dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + + dev->vendor = vendor; + dev->adev = adev; + nmk_i2c_of_probe(np, dev); + + if (dev->tft > max_fifo_threshold) { + dev_warn(&adev->dev, "requested TX FIFO threshold %u, adjusted down to %u\n", + dev->tft, max_fifo_threshold); + dev->tft = max_fifo_threshold; + } + + if (dev->rft > max_fifo_threshold) { + dev_warn(&adev->dev, "requested RX FIFO threshold %u, adjusted down to %u\n", + dev->rft, max_fifo_threshold); + dev->rft = max_fifo_threshold; + } + + amba_set_drvdata(adev, dev); + + dev->virtbase = devm_ioremap(&adev->dev, adev->res.start, + resource_size(&adev->res)); + if (!dev->virtbase) + return -ENOMEM; + + dev->irq = adev->irq[0]; + ret = devm_request_irq(&adev->dev, dev->irq, i2c_irq_handler, 0, + DRIVER_NAME, dev); + if (ret) + return dev_err_probe(&adev->dev, ret, + "cannot claim the irq %d\n", dev->irq); + + dev->clk = devm_clk_get_enabled(&adev->dev, NULL); + if (IS_ERR(dev->clk)) + return dev_err_probe(&adev->dev, PTR_ERR(dev->clk), + "could enable i2c clock\n"); + + init_hw(dev); + + adap = &dev->adap; + adap->dev.of_node = np; + adap->dev.parent = &adev->dev; + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_DEPRECATED; + adap->algo = &nmk_i2c_algo; + adap->timeout = msecs_to_jiffies(dev->timeout); + snprintf(adap->name, sizeof(adap->name), + "Nomadik I2C at %pR", &adev->res); + + i2c_set_adapdata(adap, dev); + + dev_info(&adev->dev, + "initialize %s on virtual base %p\n", + adap->name, dev->virtbase); + + ret = i2c_add_adapter(adap); + if (ret) + return ret; + + pm_runtime_put(&adev->dev); + + return 0; +} + +static void nmk_i2c_remove(struct amba_device *adev) +{ + struct nmk_i2c_dev *dev = amba_get_drvdata(adev); + + i2c_del_adapter(&dev->adap); + flush_i2c_fifo(dev); + disable_all_interrupts(dev); + clear_all_interrupts(dev); + /* disable the controller */ + i2c_clr_bit(dev->virtbase + I2C_CR, I2C_CR_PE); +} + +static struct i2c_vendor_data vendor_stn8815 = { + .has_mtdws = false, + .fifodepth = 16, /* Guessed from TFTR/RFTR = 7 */ +}; + +static struct i2c_vendor_data vendor_db8500 = { + .has_mtdws = true, + .fifodepth = 32, /* Guessed from TFTR/RFTR = 15 */ +}; + +static const struct amba_id nmk_i2c_ids[] = { + { + .id = 0x00180024, + .mask = 0x00ffffff, + .data = &vendor_stn8815, + }, + { + .id = 0x00380024, + .mask = 0x00ffffff, + .data = &vendor_db8500, + }, + {}, +}; + +MODULE_DEVICE_TABLE(amba, nmk_i2c_ids); + +static struct amba_driver nmk_i2c_driver = { + .drv = { + .owner = THIS_MODULE, + .name = DRIVER_NAME, + .pm = pm_ptr(&nmk_i2c_pm), + }, + .id_table = nmk_i2c_ids, + .probe = nmk_i2c_probe, + .remove = nmk_i2c_remove, +}; + +static int __init nmk_i2c_init(void) +{ + return amba_driver_register(&nmk_i2c_driver); +} + +static void __exit nmk_i2c_exit(void) +{ + amba_driver_unregister(&nmk_i2c_driver); +} + +subsys_initcall(nmk_i2c_init); +module_exit(nmk_i2c_exit); + +MODULE_AUTHOR("Sachin Verma"); +MODULE_AUTHOR("Srinidhi KASAGAR"); +MODULE_DESCRIPTION("Nomadik/Ux500 I2C driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c new file mode 100644 index 000000000..ae4bae63a --- /dev/null +++ b/drivers/i2c/busses/i2c-npcm7xx.c @@ -0,0 +1,2415 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Nuvoton NPCM7xx I2C Controller driver + * + * Copyright (C) 2020 Nuvoton Technologies tali.perry@nuvoton.com + */ +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/debugfs.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/iopoll.h> +#include <linux/irq.h> +#include <linux/jiffies.h> +#include <linux/kernel.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +enum i2c_mode { + I2C_MASTER, + I2C_SLAVE, +}; + +/* + * External I2C Interface driver xfer indication values, which indicate status + * of the bus. + */ +enum i2c_state_ind { + I2C_NO_STATUS_IND = 0, + I2C_SLAVE_RCV_IND, + I2C_SLAVE_XMIT_IND, + I2C_SLAVE_XMIT_MISSING_DATA_IND, + I2C_SLAVE_RESTART_IND, + I2C_SLAVE_DONE_IND, + I2C_MASTER_DONE_IND, + I2C_NACK_IND, + I2C_BUS_ERR_IND, + I2C_WAKE_UP_IND, + I2C_BLOCK_BYTES_ERR_IND, + I2C_SLAVE_RCV_MISSING_DATA_IND, +}; + +/* + * Operation type values (used to define the operation currently running) + * module is interrupt driven, on each interrupt the current operation is + * checked to see if the module is currently reading or writing. + */ +enum i2c_oper { + I2C_NO_OPER = 0, + I2C_WRITE_OPER, + I2C_READ_OPER, +}; + +/* I2C Bank (module had 2 banks of registers) */ +enum i2c_bank { + I2C_BANK_0 = 0, + I2C_BANK_1, +}; + +/* Internal I2C states values (for the I2C module state machine). */ +enum i2c_state { + I2C_DISABLE = 0, + I2C_IDLE, + I2C_MASTER_START, + I2C_SLAVE_MATCH, + I2C_OPER_STARTED, + I2C_STOP_PENDING, +}; + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +/* Module supports setting multiple own slave addresses */ +enum i2c_addr { + I2C_SLAVE_ADDR1 = 0, + I2C_SLAVE_ADDR2, + I2C_SLAVE_ADDR3, + I2C_SLAVE_ADDR4, + I2C_SLAVE_ADDR5, + I2C_SLAVE_ADDR6, + I2C_SLAVE_ADDR7, + I2C_SLAVE_ADDR8, + I2C_SLAVE_ADDR9, + I2C_SLAVE_ADDR10, + I2C_GC_ADDR, + I2C_ARP_ADDR, +}; +#endif + +/* init register and default value required to enable module */ +#define NPCM_I2CSEGCTL 0xE4 + +/* Common regs */ +#define NPCM_I2CSDA 0x00 +#define NPCM_I2CST 0x02 +#define NPCM_I2CCST 0x04 +#define NPCM_I2CCTL1 0x06 +#define NPCM_I2CADDR1 0x08 +#define NPCM_I2CCTL2 0x0A +#define NPCM_I2CADDR2 0x0C +#define NPCM_I2CCTL3 0x0E +#define NPCM_I2CCST2 0x18 +#define NPCM_I2CCST3 0x19 +#define I2C_VER 0x1F + +/* BANK 0 regs */ +#define NPCM_I2CADDR3 0x10 +#define NPCM_I2CADDR7 0x11 +#define NPCM_I2CADDR4 0x12 +#define NPCM_I2CADDR8 0x13 +#define NPCM_I2CADDR5 0x14 +#define NPCM_I2CADDR9 0x15 +#define NPCM_I2CADDR6 0x16 +#define NPCM_I2CADDR10 0x17 +#define NPCM_I2CCTL4 0x1A +#define NPCM_I2CCTL5 0x1B +#define NPCM_I2CSCLLT 0x1C /* SCL Low Time */ +#define NPCM_I2CFIF_CTL 0x1D /* FIFO Control */ +#define NPCM_I2CSCLHT 0x1E /* SCL High Time */ + +/* BANK 1 regs */ +#define NPCM_I2CFIF_CTS 0x10 /* Both FIFOs Control and Status */ +#define NPCM_I2CTXF_CTL 0x12 /* Tx-FIFO Control */ +#define NPCM_I2CT_OUT 0x14 /* Bus T.O. */ +#define NPCM_I2CPEC 0x16 /* PEC Data */ +#define NPCM_I2CTXF_STS 0x1A /* Tx-FIFO Status */ +#define NPCM_I2CRXF_STS 0x1C /* Rx-FIFO Status */ +#define NPCM_I2CRXF_CTL 0x1E /* Rx-FIFO Control */ + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +/* + * npcm_i2caddr array: + * The module supports having multiple own slave addresses. + * Since the addr regs are sprinkled all over the address space, + * use this array to get the address or each register. + */ +#define I2C_NUM_OWN_ADDR 2 +#define I2C_NUM_OWN_ADDR_SUPPORTED 2 + +static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = { + NPCM_I2CADDR1, NPCM_I2CADDR2, +}; +#endif + +/* NPCM_I2CST reg fields */ +#define NPCM_I2CST_XMIT BIT(0) /* Transmit mode */ +#define NPCM_I2CST_MASTER BIT(1) /* Master mode */ +#define NPCM_I2CST_NMATCH BIT(2) /* New match */ +#define NPCM_I2CST_STASTR BIT(3) /* Stall after start */ +#define NPCM_I2CST_NEGACK BIT(4) /* Negative ACK */ +#define NPCM_I2CST_BER BIT(5) /* Bus error */ +#define NPCM_I2CST_SDAST BIT(6) /* SDA status */ +#define NPCM_I2CST_SLVSTP BIT(7) /* Slave stop */ + +/* NPCM_I2CCST reg fields */ +#define NPCM_I2CCST_BUSY BIT(0) /* Busy */ +#define NPCM_I2CCST_BB BIT(1) /* Bus busy */ +#define NPCM_I2CCST_MATCH BIT(2) /* Address match */ +#define NPCM_I2CCST_GCMATCH BIT(3) /* Global call match */ +#define NPCM_I2CCST_TSDA BIT(4) /* Test SDA line */ +#define NPCM_I2CCST_TGSCL BIT(5) /* Toggle SCL line */ +#define NPCM_I2CCST_MATCHAF BIT(6) /* Match address field */ +#define NPCM_I2CCST_ARPMATCH BIT(7) /* ARP address match */ + +/* NPCM_I2CCTL1 reg fields */ +#define NPCM_I2CCTL1_START BIT(0) /* Generate start condition */ +#define NPCM_I2CCTL1_STOP BIT(1) /* Generate stop condition */ +#define NPCM_I2CCTL1_INTEN BIT(2) /* Interrupt enable */ +#define NPCM_I2CCTL1_EOBINTE BIT(3) +#define NPCM_I2CCTL1_ACK BIT(4) +#define NPCM_I2CCTL1_GCMEN BIT(5) /* Global call match enable */ +#define NPCM_I2CCTL1_NMINTE BIT(6) /* New match interrupt enable */ +#define NPCM_I2CCTL1_STASTRE BIT(7) /* Stall after start enable */ + +/* RW1S fields (inside a RW reg): */ +#define NPCM_I2CCTL1_RWS \ + (NPCM_I2CCTL1_START | NPCM_I2CCTL1_STOP | NPCM_I2CCTL1_ACK) + +/* npcm_i2caddr reg fields */ +#define NPCM_I2CADDR_A GENMASK(6, 0) /* Address */ +#define NPCM_I2CADDR_SAEN BIT(7) /* Slave address enable */ + +/* NPCM_I2CCTL2 reg fields */ +#define I2CCTL2_ENABLE BIT(0) /* Module enable */ +#define I2CCTL2_SCLFRQ6_0 GENMASK(7, 1) /* Bits 0:6 of frequency divisor */ + +/* NPCM_I2CCTL3 reg fields */ +#define I2CCTL3_SCLFRQ8_7 GENMASK(1, 0) /* Bits 7:8 of frequency divisor */ +#define I2CCTL3_ARPMEN BIT(2) /* ARP match enable */ +#define I2CCTL3_IDL_START BIT(3) +#define I2CCTL3_400K_MODE BIT(4) +#define I2CCTL3_BNK_SEL BIT(5) +#define I2CCTL3_SDA_LVL BIT(6) +#define I2CCTL3_SCL_LVL BIT(7) + +/* NPCM_I2CCST2 reg fields */ +#define NPCM_I2CCST2_MATCHA1F BIT(0) +#define NPCM_I2CCST2_MATCHA2F BIT(1) +#define NPCM_I2CCST2_MATCHA3F BIT(2) +#define NPCM_I2CCST2_MATCHA4F BIT(3) +#define NPCM_I2CCST2_MATCHA5F BIT(4) +#define NPCM_I2CCST2_MATCHA6F BIT(5) +#define NPCM_I2CCST2_MATCHA7F BIT(5) +#define NPCM_I2CCST2_INTSTS BIT(7) + +/* NPCM_I2CCST3 reg fields */ +#define NPCM_I2CCST3_MATCHA8F BIT(0) +#define NPCM_I2CCST3_MATCHA9F BIT(1) +#define NPCM_I2CCST3_MATCHA10F BIT(2) +#define NPCM_I2CCST3_EO_BUSY BIT(7) + +/* NPCM_I2CCTL4 reg fields */ +#define I2CCTL4_HLDT GENMASK(5, 0) +#define I2CCTL4_LVL_WE BIT(7) + +/* NPCM_I2CCTL5 reg fields */ +#define I2CCTL5_DBNCT GENMASK(3, 0) + +/* NPCM_I2CFIF_CTS reg fields */ +#define NPCM_I2CFIF_CTS_RXF_TXE BIT(1) +#define NPCM_I2CFIF_CTS_RFTE_IE BIT(3) +#define NPCM_I2CFIF_CTS_CLR_FIFO BIT(6) +#define NPCM_I2CFIF_CTS_SLVRSTR BIT(7) + +/* NPCM_I2CTXF_CTL reg field */ +#define NPCM_I2CTXF_CTL_THR_TXIE BIT(6) + +/* NPCM_I2CT_OUT reg fields */ +#define NPCM_I2CT_OUT_TO_CKDIV GENMASK(5, 0) +#define NPCM_I2CT_OUT_T_OUTIE BIT(6) +#define NPCM_I2CT_OUT_T_OUTST BIT(7) + +/* NPCM_I2CTXF_STS reg fields */ +#define NPCM_I2CTXF_STS_TX_THST BIT(6) + +/* NPCM_I2CRXF_STS reg fields */ +#define NPCM_I2CRXF_STS_RX_THST BIT(6) + +/* NPCM_I2CFIF_CTL reg fields */ +#define NPCM_I2CFIF_CTL_FIFO_EN BIT(4) + +/* NPCM_I2CRXF_CTL reg fields */ +#define NPCM_I2CRXF_CTL_THR_RXIE BIT(6) + +#define MAX_I2C_HW_FIFO_SIZE 32 + +/* I2C_VER reg fields */ +#define I2C_VER_VERSION GENMASK(6, 0) +#define I2C_VER_FIFO_EN BIT(7) + +/* stall/stuck timeout in us */ +#define DEFAULT_STALL_COUNT 25 + +/* SCLFRQ field position */ +#define SCLFRQ_0_TO_6 GENMASK(6, 0) +#define SCLFRQ_7_TO_8 GENMASK(8, 7) + +/* supported clk settings. values in Hz. */ +#define I2C_FREQ_MIN_HZ 10000 +#define I2C_FREQ_MAX_HZ I2C_MAX_FAST_MODE_PLUS_FREQ + +struct npcm_i2c_data { + u8 fifo_size; + u32 segctl_init_val; + u8 txf_sts_tx_bytes; + u8 rxf_sts_rx_bytes; + u8 rxf_ctl_last_pec; +}; + +static const struct npcm_i2c_data npxm7xx_i2c_data = { + .fifo_size = 16, + .segctl_init_val = 0x0333F000, + .txf_sts_tx_bytes = GENMASK(4, 0), + .rxf_sts_rx_bytes = GENMASK(4, 0), + .rxf_ctl_last_pec = BIT(5), +}; + +static const struct npcm_i2c_data npxm8xx_i2c_data = { + .fifo_size = 32, + .segctl_init_val = 0x9333F000, + .txf_sts_tx_bytes = GENMASK(5, 0), + .rxf_sts_rx_bytes = GENMASK(5, 0), + .rxf_ctl_last_pec = BIT(7), +}; + +/* Status of one I2C module */ +struct npcm_i2c { + struct i2c_adapter adap; + struct device *dev; + unsigned char __iomem *reg; + const struct npcm_i2c_data *data; + spinlock_t lock; /* IRQ synchronization */ + struct completion cmd_complete; + int cmd_err; + struct i2c_msg *msgs; + int msgs_num; + int num; + u32 apb_clk; + struct i2c_bus_recovery_info rinfo; + enum i2c_state state; + enum i2c_oper operation; + enum i2c_mode master_or_slave; + enum i2c_state_ind stop_ind; + u8 dest_addr; + u8 *rd_buf; + u16 rd_size; + u16 rd_ind; + u8 *wr_buf; + u16 wr_size; + u16 wr_ind; + bool fifo_use; + u16 PEC_mask; /* PEC bit mask per slave address */ + bool PEC_use; + bool read_block_use; + unsigned long int_time_stamp; + unsigned long bus_freq; /* in Hz */ +#if IS_ENABLED(CONFIG_I2C_SLAVE) + u8 own_slave_addr; + struct i2c_client *slave; + int slv_rd_size; + int slv_rd_ind; + int slv_wr_size; + int slv_wr_ind; + u8 slv_rd_buf[MAX_I2C_HW_FIFO_SIZE]; + u8 slv_wr_buf[MAX_I2C_HW_FIFO_SIZE]; +#endif + struct dentry *debugfs; /* debugfs device directory */ + u64 ber_cnt; + u64 rec_succ_cnt; + u64 rec_fail_cnt; + u64 nack_cnt; + u64 timeout_cnt; + u64 tx_complete_cnt; +}; + +static inline void npcm_i2c_select_bank(struct npcm_i2c *bus, + enum i2c_bank bank) +{ + u8 i2cctl3 = ioread8(bus->reg + NPCM_I2CCTL3); + + if (bank == I2C_BANK_0) + i2cctl3 = i2cctl3 & ~I2CCTL3_BNK_SEL; + else + i2cctl3 = i2cctl3 | I2CCTL3_BNK_SEL; + iowrite8(i2cctl3, bus->reg + NPCM_I2CCTL3); +} + +static void npcm_i2c_init_params(struct npcm_i2c *bus) +{ + bus->stop_ind = I2C_NO_STATUS_IND; + bus->rd_size = 0; + bus->wr_size = 0; + bus->rd_ind = 0; + bus->wr_ind = 0; + bus->read_block_use = false; + bus->int_time_stamp = 0; + bus->PEC_use = false; + bus->PEC_mask = 0; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + if (bus->slave) + bus->master_or_slave = I2C_SLAVE; +#endif +} + +static inline void npcm_i2c_wr_byte(struct npcm_i2c *bus, u8 data) +{ + iowrite8(data, bus->reg + NPCM_I2CSDA); +} + +static inline u8 npcm_i2c_rd_byte(struct npcm_i2c *bus) +{ + return ioread8(bus->reg + NPCM_I2CSDA); +} + +static int npcm_i2c_get_SCL(struct i2c_adapter *_adap) +{ + struct npcm_i2c *bus = container_of(_adap, struct npcm_i2c, adap); + + return !!(I2CCTL3_SCL_LVL & ioread8(bus->reg + NPCM_I2CCTL3)); +} + +static int npcm_i2c_get_SDA(struct i2c_adapter *_adap) +{ + struct npcm_i2c *bus = container_of(_adap, struct npcm_i2c, adap); + + return !!(I2CCTL3_SDA_LVL & ioread8(bus->reg + NPCM_I2CCTL3)); +} + +static inline u16 npcm_i2c_get_index(struct npcm_i2c *bus) +{ + if (bus->operation == I2C_READ_OPER) + return bus->rd_ind; + if (bus->operation == I2C_WRITE_OPER) + return bus->wr_ind; + return 0; +} + +/* quick protocol (just address) */ +static inline bool npcm_i2c_is_quick(struct npcm_i2c *bus) +{ + return bus->wr_size == 0 && bus->rd_size == 0; +} + +static void npcm_i2c_disable(struct npcm_i2c *bus) +{ + u8 i2cctl2; + +#if IS_ENABLED(CONFIG_I2C_SLAVE) + int i; + + /* Slave addresses removal */ + for (i = I2C_SLAVE_ADDR1; i < I2C_NUM_OWN_ADDR_SUPPORTED; i++) + iowrite8(0, bus->reg + npcm_i2caddr[i]); + +#endif + /* Disable module */ + i2cctl2 = ioread8(bus->reg + NPCM_I2CCTL2); + i2cctl2 = i2cctl2 & ~I2CCTL2_ENABLE; + iowrite8(i2cctl2, bus->reg + NPCM_I2CCTL2); + + bus->state = I2C_DISABLE; +} + +static void npcm_i2c_enable(struct npcm_i2c *bus) +{ + u8 i2cctl2 = ioread8(bus->reg + NPCM_I2CCTL2); + + i2cctl2 = i2cctl2 | I2CCTL2_ENABLE; + iowrite8(i2cctl2, bus->reg + NPCM_I2CCTL2); + bus->state = I2C_IDLE; +} + +/* enable\disable end of busy (EOB) interrupts */ +static inline void npcm_i2c_eob_int(struct npcm_i2c *bus, bool enable) +{ + u8 val; + + /* Clear EO_BUSY pending bit: */ + val = ioread8(bus->reg + NPCM_I2CCST3); + val = val | NPCM_I2CCST3_EO_BUSY; + iowrite8(val, bus->reg + NPCM_I2CCST3); + + val = ioread8(bus->reg + NPCM_I2CCTL1); + val &= ~NPCM_I2CCTL1_RWS; + if (enable) + val |= NPCM_I2CCTL1_EOBINTE; + else + val &= ~NPCM_I2CCTL1_EOBINTE; + iowrite8(val, bus->reg + NPCM_I2CCTL1); +} + +static inline bool npcm_i2c_tx_fifo_empty(struct npcm_i2c *bus) +{ + u8 tx_fifo_sts; + + tx_fifo_sts = ioread8(bus->reg + NPCM_I2CTXF_STS); + /* check if TX FIFO is not empty */ + if ((tx_fifo_sts & bus->data->txf_sts_tx_bytes) == 0) + return false; + + /* check if TX FIFO status bit is set: */ + return !!FIELD_GET(NPCM_I2CTXF_STS_TX_THST, tx_fifo_sts); +} + +static inline bool npcm_i2c_rx_fifo_full(struct npcm_i2c *bus) +{ + u8 rx_fifo_sts; + + rx_fifo_sts = ioread8(bus->reg + NPCM_I2CRXF_STS); + /* check if RX FIFO is not empty: */ + if ((rx_fifo_sts & bus->data->rxf_sts_rx_bytes) == 0) + return false; + + /* check if rx fifo full status is set: */ + return !!FIELD_GET(NPCM_I2CRXF_STS_RX_THST, rx_fifo_sts); +} + +static inline void npcm_i2c_clear_fifo_int(struct npcm_i2c *bus) +{ + u8 val; + + val = ioread8(bus->reg + NPCM_I2CFIF_CTS); + val = (val & NPCM_I2CFIF_CTS_SLVRSTR) | NPCM_I2CFIF_CTS_RXF_TXE; + iowrite8(val, bus->reg + NPCM_I2CFIF_CTS); +} + +static inline void npcm_i2c_clear_tx_fifo(struct npcm_i2c *bus) +{ + u8 val; + + val = ioread8(bus->reg + NPCM_I2CTXF_STS); + val = val | NPCM_I2CTXF_STS_TX_THST; + iowrite8(val, bus->reg + NPCM_I2CTXF_STS); +} + +static inline void npcm_i2c_clear_rx_fifo(struct npcm_i2c *bus) +{ + u8 val; + + val = ioread8(bus->reg + NPCM_I2CRXF_STS); + val = val | NPCM_I2CRXF_STS_RX_THST; + iowrite8(val, bus->reg + NPCM_I2CRXF_STS); +} + +static void npcm_i2c_int_enable(struct npcm_i2c *bus, bool enable) +{ + u8 val; + + val = ioread8(bus->reg + NPCM_I2CCTL1); + val &= ~NPCM_I2CCTL1_RWS; + if (enable) + val |= NPCM_I2CCTL1_INTEN; + else + val &= ~NPCM_I2CCTL1_INTEN; + iowrite8(val, bus->reg + NPCM_I2CCTL1); +} + +static inline void npcm_i2c_master_start(struct npcm_i2c *bus) +{ + u8 val; + + val = ioread8(bus->reg + NPCM_I2CCTL1); + val &= ~(NPCM_I2CCTL1_STOP | NPCM_I2CCTL1_ACK); + val |= NPCM_I2CCTL1_START; + iowrite8(val, bus->reg + NPCM_I2CCTL1); +} + +static inline void npcm_i2c_master_stop(struct npcm_i2c *bus) +{ + u8 val; + + /* + * override HW issue: I2C may fail to supply stop condition in Master + * Write operation. + * Need to delay at least 5 us from the last int, before issueing a stop + */ + udelay(10); /* function called from interrupt, can't sleep */ + val = ioread8(bus->reg + NPCM_I2CCTL1); + val &= ~(NPCM_I2CCTL1_START | NPCM_I2CCTL1_ACK); + val |= NPCM_I2CCTL1_STOP; + iowrite8(val, bus->reg + NPCM_I2CCTL1); + + if (!bus->fifo_use) + return; + + npcm_i2c_select_bank(bus, I2C_BANK_1); + + if (bus->operation == I2C_READ_OPER) + npcm_i2c_clear_rx_fifo(bus); + else + npcm_i2c_clear_tx_fifo(bus); + npcm_i2c_clear_fifo_int(bus); + iowrite8(0, bus->reg + NPCM_I2CTXF_CTL); +} + +static inline void npcm_i2c_stall_after_start(struct npcm_i2c *bus, bool stall) +{ + u8 val; + + val = ioread8(bus->reg + NPCM_I2CCTL1); + val &= ~NPCM_I2CCTL1_RWS; + if (stall) + val |= NPCM_I2CCTL1_STASTRE; + else + val &= ~NPCM_I2CCTL1_STASTRE; + iowrite8(val, bus->reg + NPCM_I2CCTL1); +} + +static inline void npcm_i2c_nack(struct npcm_i2c *bus) +{ + u8 val; + + val = ioread8(bus->reg + NPCM_I2CCTL1); + val &= ~(NPCM_I2CCTL1_STOP | NPCM_I2CCTL1_START); + val |= NPCM_I2CCTL1_ACK; + iowrite8(val, bus->reg + NPCM_I2CCTL1); +} + +static inline void npcm_i2c_clear_master_status(struct npcm_i2c *bus) +{ + u8 val; + + /* Clear NEGACK, STASTR and BER bits */ + val = NPCM_I2CST_BER | NPCM_I2CST_NEGACK | NPCM_I2CST_STASTR; + iowrite8(val, bus->reg + NPCM_I2CST); +} + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +static void npcm_i2c_slave_int_enable(struct npcm_i2c *bus, bool enable) +{ + u8 i2cctl1; + + /* enable interrupt on slave match: */ + i2cctl1 = ioread8(bus->reg + NPCM_I2CCTL1); + i2cctl1 &= ~NPCM_I2CCTL1_RWS; + if (enable) + i2cctl1 |= NPCM_I2CCTL1_NMINTE; + else + i2cctl1 &= ~NPCM_I2CCTL1_NMINTE; + iowrite8(i2cctl1, bus->reg + NPCM_I2CCTL1); +} + +static int npcm_i2c_slave_enable(struct npcm_i2c *bus, enum i2c_addr addr_type, + u8 addr, bool enable) +{ + u8 i2cctl1; + u8 i2cctl3; + u8 sa_reg; + + sa_reg = (addr & 0x7F) | FIELD_PREP(NPCM_I2CADDR_SAEN, enable); + if (addr_type == I2C_GC_ADDR) { + i2cctl1 = ioread8(bus->reg + NPCM_I2CCTL1); + if (enable) + i2cctl1 |= NPCM_I2CCTL1_GCMEN; + else + i2cctl1 &= ~NPCM_I2CCTL1_GCMEN; + iowrite8(i2cctl1, bus->reg + NPCM_I2CCTL1); + return 0; + } else if (addr_type == I2C_ARP_ADDR) { + i2cctl3 = ioread8(bus->reg + NPCM_I2CCTL3); + if (enable) + i2cctl3 |= I2CCTL3_ARPMEN; + else + i2cctl3 &= ~I2CCTL3_ARPMEN; + iowrite8(i2cctl3, bus->reg + NPCM_I2CCTL3); + return 0; + } + if (addr_type > I2C_SLAVE_ADDR2 && addr_type <= I2C_SLAVE_ADDR10) + dev_err(bus->dev, "try to enable more than 2 SA not supported\n"); + + if (addr_type >= I2C_ARP_ADDR) + return -EFAULT; + + /* Set and enable the address */ + iowrite8(sa_reg, bus->reg + npcm_i2caddr[addr_type]); + npcm_i2c_slave_int_enable(bus, enable); + + return 0; +} +#endif + +static void npcm_i2c_reset(struct npcm_i2c *bus) +{ + /* + * Save I2CCTL1 relevant bits. It is being cleared when the module + * is disabled. + */ + u8 i2cctl1; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + u8 addr; +#endif + + i2cctl1 = ioread8(bus->reg + NPCM_I2CCTL1); + + npcm_i2c_disable(bus); + npcm_i2c_enable(bus); + + /* Restore NPCM_I2CCTL1 Status */ + i2cctl1 &= ~NPCM_I2CCTL1_RWS; + iowrite8(i2cctl1, bus->reg + NPCM_I2CCTL1); + + /* Clear BB (BUS BUSY) bit */ + iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST); + iowrite8(0xFF, bus->reg + NPCM_I2CST); + + /* Clear and disable EOB */ + npcm_i2c_eob_int(bus, false); + + /* Clear all fifo bits: */ + iowrite8(NPCM_I2CFIF_CTS_CLR_FIFO, bus->reg + NPCM_I2CFIF_CTS); + +#if IS_ENABLED(CONFIG_I2C_SLAVE) + if (bus->slave) { + addr = bus->slave->addr; + npcm_i2c_slave_enable(bus, I2C_SLAVE_ADDR1, addr, true); + } +#endif + + /* Clear status bits for spurious interrupts */ + npcm_i2c_clear_master_status(bus); + + bus->state = I2C_IDLE; +} + +static inline bool npcm_i2c_is_master(struct npcm_i2c *bus) +{ + return !!FIELD_GET(NPCM_I2CST_MASTER, ioread8(bus->reg + NPCM_I2CST)); +} + +static void npcm_i2c_callback(struct npcm_i2c *bus, + enum i2c_state_ind op_status, u16 info) +{ + struct i2c_msg *msgs; + int msgs_num; + bool do_complete = false; + + msgs = bus->msgs; + msgs_num = bus->msgs_num; + /* + * check that transaction was not timed-out, and msgs still + * holds a valid value. + */ + if (!msgs) + return; + + if (completion_done(&bus->cmd_complete)) + return; + + switch (op_status) { + case I2C_MASTER_DONE_IND: + bus->cmd_err = bus->msgs_num; + if (bus->tx_complete_cnt < ULLONG_MAX) + bus->tx_complete_cnt++; + fallthrough; + case I2C_BLOCK_BYTES_ERR_IND: + /* Master tx finished and all transmit bytes were sent */ + if (bus->msgs) { + if (msgs[0].flags & I2C_M_RD) + msgs[0].len = info; + else if (msgs_num == 2 && + msgs[1].flags & I2C_M_RD) + msgs[1].len = info; + } + do_complete = true; + break; + case I2C_NACK_IND: + /* MASTER transmit got a NACK before tx all bytes */ + bus->cmd_err = -ENXIO; + do_complete = true; + break; + case I2C_BUS_ERR_IND: + /* Bus error */ + bus->cmd_err = -EAGAIN; + do_complete = true; + break; + case I2C_WAKE_UP_IND: + /* I2C wake up */ + break; + default: + break; + } + + bus->operation = I2C_NO_OPER; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + if (bus->slave) + bus->master_or_slave = I2C_SLAVE; +#endif + if (do_complete) + complete(&bus->cmd_complete); +} + +static u8 npcm_i2c_fifo_usage(struct npcm_i2c *bus) +{ + if (bus->operation == I2C_WRITE_OPER) + return (bus->data->txf_sts_tx_bytes & + ioread8(bus->reg + NPCM_I2CTXF_STS)); + if (bus->operation == I2C_READ_OPER) + return (bus->data->rxf_sts_rx_bytes & + ioread8(bus->reg + NPCM_I2CRXF_STS)); + return 0; +} + +static void npcm_i2c_write_to_fifo_master(struct npcm_i2c *bus, u16 max_bytes) +{ + u8 size_free_fifo; + + /* + * Fill the FIFO, while the FIFO is not full and there are more bytes + * to write + */ + size_free_fifo = bus->data->fifo_size - npcm_i2c_fifo_usage(bus); + while (max_bytes-- && size_free_fifo) { + if (bus->wr_ind < bus->wr_size) + npcm_i2c_wr_byte(bus, bus->wr_buf[bus->wr_ind++]); + else + npcm_i2c_wr_byte(bus, 0xFF); + size_free_fifo = bus->data->fifo_size - npcm_i2c_fifo_usage(bus); + } +} + +/* + * npcm_i2c_set_fifo: + * configure the FIFO before using it. If nread is -1 RX FIFO will not be + * configured. same for nwrite + */ +static void npcm_i2c_set_fifo(struct npcm_i2c *bus, int nread, int nwrite) +{ + u8 rxf_ctl = 0; + + if (!bus->fifo_use) + return; + npcm_i2c_select_bank(bus, I2C_BANK_1); + npcm_i2c_clear_tx_fifo(bus); + npcm_i2c_clear_rx_fifo(bus); + + /* configure RX FIFO */ + if (nread > 0) { + rxf_ctl = min_t(int, nread, bus->data->fifo_size); + + /* set LAST bit. if LAST is set next FIFO packet is nacked */ + if (nread <= bus->data->fifo_size) + rxf_ctl |= bus->data->rxf_ctl_last_pec; + + /* + * if we are about to read the first byte in blk rd mode, + * don't NACK it. If slave returns zero size HW can't NACK + * it immediately, it will read extra byte and then NACK. + */ + if (bus->rd_ind == 0 && bus->read_block_use) { + /* set fifo to read one byte, no last: */ + rxf_ctl = 1; + } + + /* set fifo size: */ + iowrite8(rxf_ctl, bus->reg + NPCM_I2CRXF_CTL); + } + + /* configure TX FIFO */ + if (nwrite > 0) { + if (nwrite > bus->data->fifo_size) + /* data to send is more then FIFO size. */ + iowrite8(bus->data->fifo_size, bus->reg + NPCM_I2CTXF_CTL); + else + iowrite8(nwrite, bus->reg + NPCM_I2CTXF_CTL); + + npcm_i2c_clear_tx_fifo(bus); + } +} + +static void npcm_i2c_read_fifo(struct npcm_i2c *bus, u8 bytes_in_fifo) +{ + u8 data; + + while (bytes_in_fifo--) { + data = npcm_i2c_rd_byte(bus); + if (bus->rd_ind < bus->rd_size) + bus->rd_buf[bus->rd_ind++] = data; + } +} + +static void npcm_i2c_master_abort(struct npcm_i2c *bus) +{ + /* Only current master is allowed to issue a stop condition */ + if (!npcm_i2c_is_master(bus)) + return; + + npcm_i2c_eob_int(bus, true); + npcm_i2c_master_stop(bus); + npcm_i2c_clear_master_status(bus); +} + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +static u8 npcm_i2c_get_slave_addr(struct npcm_i2c *bus, enum i2c_addr addr_type) +{ + u8 slave_add; + + if (addr_type > I2C_SLAVE_ADDR2 && addr_type <= I2C_SLAVE_ADDR10) + dev_err(bus->dev, "get slave: try to use more than 2 SA not supported\n"); + + slave_add = ioread8(bus->reg + npcm_i2caddr[(int)addr_type]); + + return slave_add; +} + +static int npcm_i2c_remove_slave_addr(struct npcm_i2c *bus, u8 slave_add) +{ + int i; + + /* Set the enable bit */ + slave_add |= 0x80; + + for (i = I2C_SLAVE_ADDR1; i < I2C_NUM_OWN_ADDR_SUPPORTED; i++) { + if (ioread8(bus->reg + npcm_i2caddr[i]) == slave_add) + iowrite8(0, bus->reg + npcm_i2caddr[i]); + } + + return 0; +} + +static void npcm_i2c_write_fifo_slave(struct npcm_i2c *bus, u16 max_bytes) +{ + /* + * Fill the FIFO, while the FIFO is not full and there are more bytes + * to write + */ + npcm_i2c_clear_fifo_int(bus); + npcm_i2c_clear_tx_fifo(bus); + iowrite8(0, bus->reg + NPCM_I2CTXF_CTL); + while (max_bytes-- && bus->data->fifo_size != npcm_i2c_fifo_usage(bus)) { + if (bus->slv_wr_size <= 0) + break; + bus->slv_wr_ind = bus->slv_wr_ind & (bus->data->fifo_size - 1); + npcm_i2c_wr_byte(bus, bus->slv_wr_buf[bus->slv_wr_ind]); + bus->slv_wr_ind++; + bus->slv_wr_ind = bus->slv_wr_ind & (bus->data->fifo_size - 1); + bus->slv_wr_size--; + } +} + +static void npcm_i2c_read_fifo_slave(struct npcm_i2c *bus, u8 bytes_in_fifo) +{ + u8 data; + + if (!bus->slave) + return; + + while (bytes_in_fifo--) { + data = npcm_i2c_rd_byte(bus); + + bus->slv_rd_ind = bus->slv_rd_ind & (bus->data->fifo_size - 1); + bus->slv_rd_buf[bus->slv_rd_ind] = data; + bus->slv_rd_ind++; + + /* 1st byte is length in block protocol: */ + if (bus->slv_rd_ind == 1 && bus->read_block_use) + bus->slv_rd_size = data + bus->PEC_use + 1; + } +} + +static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus) +{ + int i; + u8 value; + int ind; + int ret = bus->slv_wr_ind; + + /* fill a cyclic buffer */ + for (i = 0; i < bus->data->fifo_size; i++) { + if (bus->slv_wr_size >= bus->data->fifo_size) + break; + if (bus->state == I2C_SLAVE_MATCH) { + i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value); + bus->state = I2C_OPER_STARTED; + } else { + i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value); + } + ind = (bus->slv_wr_ind + bus->slv_wr_size) & (bus->data->fifo_size - 1); + bus->slv_wr_buf[ind] = value; + bus->slv_wr_size++; + } + return bus->data->fifo_size - ret; +} + +static void npcm_i2c_slave_send_rd_buf(struct npcm_i2c *bus) +{ + int i; + + for (i = 0; i < bus->slv_rd_ind; i++) + i2c_slave_event(bus->slave, I2C_SLAVE_WRITE_RECEIVED, + &bus->slv_rd_buf[i]); + /* + * once we send bytes up, need to reset the counter of the wr buf + * got data from master (new offset in device), ignore wr fifo: + */ + if (bus->slv_rd_ind) { + bus->slv_wr_size = 0; + bus->slv_wr_ind = 0; + } + + bus->slv_rd_ind = 0; + bus->slv_rd_size = bus->adap.quirks->max_read_len; + + npcm_i2c_clear_fifo_int(bus); + npcm_i2c_clear_rx_fifo(bus); +} + +static void npcm_i2c_slave_receive(struct npcm_i2c *bus, u16 nread, + u8 *read_data) +{ + bus->state = I2C_OPER_STARTED; + bus->operation = I2C_READ_OPER; + bus->slv_rd_size = nread; + bus->slv_rd_ind = 0; + + iowrite8(0, bus->reg + NPCM_I2CTXF_CTL); + iowrite8(bus->data->fifo_size, bus->reg + NPCM_I2CRXF_CTL); + npcm_i2c_clear_tx_fifo(bus); + npcm_i2c_clear_rx_fifo(bus); +} + +static void npcm_i2c_slave_xmit(struct npcm_i2c *bus, u16 nwrite, + u8 *write_data) +{ + if (nwrite == 0) + return; + + bus->operation = I2C_WRITE_OPER; + + /* get the next buffer */ + npcm_i2c_slave_get_wr_buf(bus); + npcm_i2c_write_fifo_slave(bus, nwrite); +} + +/* + * npcm_i2c_slave_wr_buf_sync: + * currently slave IF only supports single byte operations. + * in order to utilize the npcm HW FIFO, the driver will ask for 16 bytes + * at a time, pack them in buffer, and then transmit them all together + * to the FIFO and onward to the bus. + * NACK on read will be once reached to bus->adap->quirks->max_read_len. + * sending a NACK wherever the backend requests for it is not supported. + * the next two functions allow reading to local buffer before writing it all + * to the HW FIFO. + */ +static void npcm_i2c_slave_wr_buf_sync(struct npcm_i2c *bus) +{ + int left_in_fifo; + + left_in_fifo = bus->data->txf_sts_tx_bytes & + ioread8(bus->reg + NPCM_I2CTXF_STS); + + /* fifo already full: */ + if (left_in_fifo >= bus->data->fifo_size || + bus->slv_wr_size >= bus->data->fifo_size) + return; + + /* update the wr fifo index back to the untransmitted bytes: */ + bus->slv_wr_ind = bus->slv_wr_ind - left_in_fifo; + bus->slv_wr_size = bus->slv_wr_size + left_in_fifo; + + if (bus->slv_wr_ind < 0) + bus->slv_wr_ind += bus->data->fifo_size; +} + +static void npcm_i2c_slave_rd_wr(struct npcm_i2c *bus) +{ + if (NPCM_I2CST_XMIT & ioread8(bus->reg + NPCM_I2CST)) { + /* + * Slave got an address match with direction bit 1 so it should + * transmit data. Write till the master will NACK + */ + bus->operation = I2C_WRITE_OPER; + npcm_i2c_slave_xmit(bus, bus->adap.quirks->max_write_len, + bus->slv_wr_buf); + } else { + /* + * Slave got an address match with direction bit 0 so it should + * receive data. + * this module does not support saying no to bytes. + * it will always ACK. + */ + bus->operation = I2C_READ_OPER; + npcm_i2c_read_fifo_slave(bus, npcm_i2c_fifo_usage(bus)); + bus->stop_ind = I2C_SLAVE_RCV_IND; + npcm_i2c_slave_send_rd_buf(bus); + npcm_i2c_slave_receive(bus, bus->adap.quirks->max_read_len, + bus->slv_rd_buf); + } +} + +static irqreturn_t npcm_i2c_int_slave_handler(struct npcm_i2c *bus) +{ + u8 val; + irqreturn_t ret = IRQ_NONE; + u8 i2cst = ioread8(bus->reg + NPCM_I2CST); + + /* Slave: A NACK has occurred */ + if (NPCM_I2CST_NEGACK & i2cst) { + bus->stop_ind = I2C_NACK_IND; + npcm_i2c_slave_wr_buf_sync(bus); + if (bus->fifo_use) + /* clear the FIFO */ + iowrite8(NPCM_I2CFIF_CTS_CLR_FIFO, + bus->reg + NPCM_I2CFIF_CTS); + + /* In slave write, NACK is OK, otherwise it is a problem */ + bus->stop_ind = I2C_NO_STATUS_IND; + bus->operation = I2C_NO_OPER; + bus->own_slave_addr = 0xFF; + + /* + * Slave has to wait for STOP to decide this is the end + * of the transaction. tx is not yet considered as done + */ + iowrite8(NPCM_I2CST_NEGACK, bus->reg + NPCM_I2CST); + + ret = IRQ_HANDLED; + } + + /* Slave mode: a Bus Error (BER) has been identified */ + if (NPCM_I2CST_BER & i2cst) { + /* + * Check whether bus arbitration or Start or Stop during data + * xfer bus arbitration problem should not result in recovery + */ + bus->stop_ind = I2C_BUS_ERR_IND; + + /* wait for bus busy before clear fifo */ + iowrite8(NPCM_I2CFIF_CTS_CLR_FIFO, bus->reg + NPCM_I2CFIF_CTS); + + bus->state = I2C_IDLE; + + /* + * in BER case we might get 2 interrupts: one for slave one for + * master ( for a channel which is master\slave switching) + */ + if (completion_done(&bus->cmd_complete) == false) { + bus->cmd_err = -EIO; + complete(&bus->cmd_complete); + } + bus->own_slave_addr = 0xFF; + iowrite8(NPCM_I2CST_BER, bus->reg + NPCM_I2CST); + ret = IRQ_HANDLED; + } + + /* A Slave Stop Condition has been identified */ + if (NPCM_I2CST_SLVSTP & i2cst) { + u8 bytes_in_fifo = npcm_i2c_fifo_usage(bus); + + bus->stop_ind = I2C_SLAVE_DONE_IND; + + if (bus->operation == I2C_READ_OPER) + npcm_i2c_read_fifo_slave(bus, bytes_in_fifo); + + /* if the buffer is empty nothing will be sent */ + npcm_i2c_slave_send_rd_buf(bus); + + /* Slave done transmitting or receiving */ + bus->stop_ind = I2C_NO_STATUS_IND; + + /* + * Note, just because we got here, it doesn't mean we through + * away the wr buffer. + * we keep it until the next received offset. + */ + bus->operation = I2C_NO_OPER; + bus->own_slave_addr = 0xFF; + i2c_slave_event(bus->slave, I2C_SLAVE_STOP, 0); + iowrite8(NPCM_I2CST_SLVSTP, bus->reg + NPCM_I2CST); + if (bus->fifo_use) { + npcm_i2c_clear_fifo_int(bus); + npcm_i2c_clear_rx_fifo(bus); + npcm_i2c_clear_tx_fifo(bus); + + iowrite8(NPCM_I2CFIF_CTS_CLR_FIFO, + bus->reg + NPCM_I2CFIF_CTS); + } + bus->state = I2C_IDLE; + ret = IRQ_HANDLED; + } + + /* restart condition occurred and Rx-FIFO was not empty */ + if (bus->fifo_use && FIELD_GET(NPCM_I2CFIF_CTS_SLVRSTR, + ioread8(bus->reg + NPCM_I2CFIF_CTS))) { + bus->stop_ind = I2C_SLAVE_RESTART_IND; + bus->master_or_slave = I2C_SLAVE; + if (bus->operation == I2C_READ_OPER) + npcm_i2c_read_fifo_slave(bus, npcm_i2c_fifo_usage(bus)); + bus->operation = I2C_WRITE_OPER; + iowrite8(0, bus->reg + NPCM_I2CRXF_CTL); + val = NPCM_I2CFIF_CTS_CLR_FIFO | NPCM_I2CFIF_CTS_SLVRSTR | + NPCM_I2CFIF_CTS_RXF_TXE; + iowrite8(val, bus->reg + NPCM_I2CFIF_CTS); + npcm_i2c_slave_rd_wr(bus); + ret = IRQ_HANDLED; + } + + /* A Slave Address Match has been identified */ + if (NPCM_I2CST_NMATCH & i2cst) { + u8 info = 0; + + /* Address match automatically implies slave mode */ + bus->master_or_slave = I2C_SLAVE; + npcm_i2c_clear_fifo_int(bus); + npcm_i2c_clear_rx_fifo(bus); + npcm_i2c_clear_tx_fifo(bus); + iowrite8(0, bus->reg + NPCM_I2CTXF_CTL); + iowrite8(bus->data->fifo_size, bus->reg + NPCM_I2CRXF_CTL); + if (NPCM_I2CST_XMIT & i2cst) { + bus->operation = I2C_WRITE_OPER; + } else { + i2c_slave_event(bus->slave, I2C_SLAVE_WRITE_REQUESTED, + &info); + bus->operation = I2C_READ_OPER; + } + if (bus->own_slave_addr == 0xFF) { + /* Check which type of address match */ + val = ioread8(bus->reg + NPCM_I2CCST); + if (NPCM_I2CCST_MATCH & val) { + u16 addr; + enum i2c_addr eaddr; + u8 i2ccst2; + u8 i2ccst3; + + i2ccst3 = ioread8(bus->reg + NPCM_I2CCST3); + i2ccst2 = ioread8(bus->reg + NPCM_I2CCST2); + + /* + * the i2c module can response to 10 own SA. + * check which one was addressed by the master. + * respond to the first one. + */ + addr = ((i2ccst3 & 0x07) << 7) | + (i2ccst2 & 0x7F); + info = ffs(addr); + eaddr = (enum i2c_addr)info; + addr = npcm_i2c_get_slave_addr(bus, eaddr); + addr &= 0x7F; + bus->own_slave_addr = addr; + if (bus->PEC_mask & BIT(info)) + bus->PEC_use = true; + else + bus->PEC_use = false; + } else { + if (NPCM_I2CCST_GCMATCH & val) + bus->own_slave_addr = 0; + if (NPCM_I2CCST_ARPMATCH & val) + bus->own_slave_addr = 0x61; + } + } else { + /* + * Slave match can happen in two options: + * 1. Start, SA, read (slave read without further ado) + * 2. Start, SA, read, data, restart, SA, read, ... + * (slave read in fragmented mode) + * 3. Start, SA, write, data, restart, SA, read, .. + * (regular write-read mode) + */ + if ((bus->state == I2C_OPER_STARTED && + bus->operation == I2C_READ_OPER && + bus->stop_ind == I2C_SLAVE_XMIT_IND) || + bus->stop_ind == I2C_SLAVE_RCV_IND) { + /* slave tx after slave rx w/o STOP */ + bus->stop_ind = I2C_SLAVE_RESTART_IND; + } + } + + if (NPCM_I2CST_XMIT & i2cst) + bus->stop_ind = I2C_SLAVE_XMIT_IND; + else + bus->stop_ind = I2C_SLAVE_RCV_IND; + bus->state = I2C_SLAVE_MATCH; + npcm_i2c_slave_rd_wr(bus); + iowrite8(NPCM_I2CST_NMATCH, bus->reg + NPCM_I2CST); + ret = IRQ_HANDLED; + } + + /* Slave SDA status is set - tx or rx */ + if ((NPCM_I2CST_SDAST & i2cst) || + (bus->fifo_use && + (npcm_i2c_tx_fifo_empty(bus) || npcm_i2c_rx_fifo_full(bus)))) { + npcm_i2c_slave_rd_wr(bus); + iowrite8(NPCM_I2CST_SDAST, bus->reg + NPCM_I2CST); + ret = IRQ_HANDLED; + } /* SDAST */ + + /* + * If irq is not one of the above, make sure EOB is disabled and all + * status bits are cleared. + */ + if (ret == IRQ_NONE) { + npcm_i2c_eob_int(bus, false); + npcm_i2c_clear_master_status(bus); + } + + return IRQ_HANDLED; +} + +static int npcm_i2c_reg_slave(struct i2c_client *client) +{ + unsigned long lock_flags; + struct npcm_i2c *bus = i2c_get_adapdata(client->adapter); + + bus->slave = client; + + if (!bus->slave) + return -EINVAL; + + if (client->flags & I2C_CLIENT_TEN) + return -EAFNOSUPPORT; + + spin_lock_irqsave(&bus->lock, lock_flags); + + npcm_i2c_init_params(bus); + bus->slv_rd_size = 0; + bus->slv_wr_size = 0; + bus->slv_rd_ind = 0; + bus->slv_wr_ind = 0; + if (client->flags & I2C_CLIENT_PEC) + bus->PEC_use = true; + + dev_info(bus->dev, "i2c%d register slave SA=0x%x, PEC=%d\n", bus->num, + client->addr, bus->PEC_use); + + npcm_i2c_slave_enable(bus, I2C_SLAVE_ADDR1, client->addr, true); + npcm_i2c_clear_fifo_int(bus); + npcm_i2c_clear_rx_fifo(bus); + npcm_i2c_clear_tx_fifo(bus); + npcm_i2c_slave_int_enable(bus, true); + + spin_unlock_irqrestore(&bus->lock, lock_flags); + return 0; +} + +static int npcm_i2c_unreg_slave(struct i2c_client *client) +{ + struct npcm_i2c *bus = client->adapter->algo_data; + unsigned long lock_flags; + + spin_lock_irqsave(&bus->lock, lock_flags); + if (!bus->slave) { + spin_unlock_irqrestore(&bus->lock, lock_flags); + return -EINVAL; + } + npcm_i2c_slave_int_enable(bus, false); + npcm_i2c_remove_slave_addr(bus, client->addr); + bus->slave = NULL; + spin_unlock_irqrestore(&bus->lock, lock_flags); + return 0; +} +#endif /* CONFIG_I2C_SLAVE */ + +static void npcm_i2c_master_fifo_read(struct npcm_i2c *bus) +{ + int rcount; + int fifo_bytes; + enum i2c_state_ind ind = I2C_MASTER_DONE_IND; + + fifo_bytes = npcm_i2c_fifo_usage(bus); + rcount = bus->rd_size - bus->rd_ind; + + /* + * In order not to change the RX_TRH during transaction (we found that + * this might be problematic if it takes too much time to read the FIFO) + * we read the data in the following way. If the number of bytes to + * read == FIFO Size + C (where C < FIFO Size)then first read C bytes + * and in the next int we read rest of the data. + */ + if (rcount < (2 * bus->data->fifo_size) && rcount > bus->data->fifo_size) + fifo_bytes = rcount - bus->data->fifo_size; + + if (rcount <= fifo_bytes) { + /* last bytes are about to be read - end of tx */ + bus->state = I2C_STOP_PENDING; + bus->stop_ind = ind; + npcm_i2c_eob_int(bus, true); + /* Stop should be set before reading last byte. */ + npcm_i2c_master_stop(bus); + npcm_i2c_read_fifo(bus, fifo_bytes); + } else { + npcm_i2c_read_fifo(bus, fifo_bytes); + rcount = bus->rd_size - bus->rd_ind; + npcm_i2c_set_fifo(bus, rcount, -1); + } +} + +static void npcm_i2c_irq_master_handler_write(struct npcm_i2c *bus) +{ + u16 wcount; + + if (bus->fifo_use) + npcm_i2c_clear_tx_fifo(bus); /* clear the TX fifo status bit */ + + /* Master write operation - last byte handling */ + if (bus->wr_ind == bus->wr_size) { + if (bus->fifo_use && npcm_i2c_fifo_usage(bus) > 0) + /* + * No more bytes to send (to add to the FIFO), + * however the FIFO is not empty yet. It is + * still in the middle of tx. Currently there's nothing + * to do except for waiting to the end of the tx + * We will get an int when the FIFO will get empty. + */ + return; + + if (bus->rd_size == 0) { + /* all bytes have been written, in wr only operation */ + npcm_i2c_eob_int(bus, true); + bus->state = I2C_STOP_PENDING; + bus->stop_ind = I2C_MASTER_DONE_IND; + npcm_i2c_master_stop(bus); + /* Clear SDA Status bit (by writing dummy byte) */ + npcm_i2c_wr_byte(bus, 0xFF); + + } else { + /* last write-byte written on previous int - restart */ + npcm_i2c_set_fifo(bus, bus->rd_size, -1); + /* Generate repeated start upon next write to SDA */ + npcm_i2c_master_start(bus); + + /* + * Receiving one byte only - stall after successful + * completion of send address byte. If we NACK here, and + * slave doesn't ACK the address, we might + * unintentionally NACK the next multi-byte read. + */ + if (bus->rd_size == 1) + npcm_i2c_stall_after_start(bus, true); + + /* Next int will occur on read */ + bus->operation = I2C_READ_OPER; + /* send the slave address in read direction */ + npcm_i2c_wr_byte(bus, bus->dest_addr | 0x1); + } + } else { + /* write next byte not last byte and not slave address */ + if (!bus->fifo_use || bus->wr_size == 1) { + npcm_i2c_wr_byte(bus, bus->wr_buf[bus->wr_ind++]); + } else { + wcount = bus->wr_size - bus->wr_ind; + npcm_i2c_set_fifo(bus, -1, wcount); + if (wcount) + npcm_i2c_write_to_fifo_master(bus, wcount); + } + } +} + +static void npcm_i2c_irq_master_handler_read(struct npcm_i2c *bus) +{ + u16 block_extra_bytes_size; + u8 data; + + /* added bytes to the packet: */ + block_extra_bytes_size = bus->read_block_use + bus->PEC_use; + + /* + * Perform master read, distinguishing between last byte and the rest of + * the bytes. The last byte should be read when the clock is stopped + */ + if (bus->rd_ind == 0) { /* first byte handling: */ + if (bus->read_block_use) { + /* first byte in block protocol is the size: */ + data = npcm_i2c_rd_byte(bus); + data = clamp_val(data, 1, I2C_SMBUS_BLOCK_MAX); + bus->rd_size = data + block_extra_bytes_size; + bus->rd_buf[bus->rd_ind++] = data; + + /* clear RX FIFO interrupt status: */ + if (bus->fifo_use) { + data = ioread8(bus->reg + NPCM_I2CFIF_CTS); + data = data | NPCM_I2CFIF_CTS_RXF_TXE; + iowrite8(data, bus->reg + NPCM_I2CFIF_CTS); + } + + npcm_i2c_set_fifo(bus, bus->rd_size - 1, -1); + npcm_i2c_stall_after_start(bus, false); + } else { + npcm_i2c_clear_tx_fifo(bus); + npcm_i2c_master_fifo_read(bus); + } + } else { + if (bus->rd_size == block_extra_bytes_size && + bus->read_block_use) { + bus->state = I2C_STOP_PENDING; + bus->stop_ind = I2C_BLOCK_BYTES_ERR_IND; + bus->cmd_err = -EIO; + npcm_i2c_eob_int(bus, true); + npcm_i2c_master_stop(bus); + npcm_i2c_read_fifo(bus, npcm_i2c_fifo_usage(bus)); + } else { + npcm_i2c_master_fifo_read(bus); + } + } +} + +static void npcm_i2c_irq_handle_nmatch(struct npcm_i2c *bus) +{ + iowrite8(NPCM_I2CST_NMATCH, bus->reg + NPCM_I2CST); + npcm_i2c_nack(bus); + bus->stop_ind = I2C_BUS_ERR_IND; + npcm_i2c_callback(bus, bus->stop_ind, npcm_i2c_get_index(bus)); +} + +/* A NACK has occurred */ +static void npcm_i2c_irq_handle_nack(struct npcm_i2c *bus) +{ + u8 val; + + if (bus->nack_cnt < ULLONG_MAX) + bus->nack_cnt++; + + if (bus->fifo_use) { + /* + * if there are still untransmitted bytes in TX FIFO + * reduce them from wr_ind + */ + if (bus->operation == I2C_WRITE_OPER) + bus->wr_ind -= npcm_i2c_fifo_usage(bus); + + /* clear the FIFO */ + iowrite8(NPCM_I2CFIF_CTS_CLR_FIFO, bus->reg + NPCM_I2CFIF_CTS); + } + + /* In master write operation, got unexpected NACK */ + bus->stop_ind = I2C_NACK_IND; + /* Only current master is allowed to issue Stop Condition */ + if (npcm_i2c_is_master(bus)) { + /* stopping in the middle */ + npcm_i2c_eob_int(bus, false); + npcm_i2c_master_stop(bus); + + /* Clear SDA Status bit (by reading dummy byte) */ + npcm_i2c_rd_byte(bus); + + /* + * The bus is released from stall only after the SW clears + * NEGACK bit. Then a Stop condition is sent. + */ + npcm_i2c_clear_master_status(bus); + readx_poll_timeout_atomic(ioread8, bus->reg + NPCM_I2CCST, val, + !(val & NPCM_I2CCST_BUSY), 10, 200); + /* Verify no status bits are still set after bus is released */ + npcm_i2c_clear_master_status(bus); + } + bus->state = I2C_IDLE; + + /* + * In Master mode, NACK should be cleared only after STOP. + * In such case, the bus is released from stall only after the + * software clears NACK bit. Then a Stop condition is sent. + */ + npcm_i2c_callback(bus, bus->stop_ind, bus->wr_ind); +} + + /* Master mode: a Bus Error has been identified */ +static void npcm_i2c_irq_handle_ber(struct npcm_i2c *bus) +{ + if (bus->ber_cnt < ULLONG_MAX) + bus->ber_cnt++; + bus->stop_ind = I2C_BUS_ERR_IND; + if (npcm_i2c_is_master(bus)) { + npcm_i2c_master_abort(bus); + } else { + npcm_i2c_clear_master_status(bus); + + /* Clear BB (BUS BUSY) bit */ + iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST); + + bus->cmd_err = -EAGAIN; + npcm_i2c_callback(bus, bus->stop_ind, npcm_i2c_get_index(bus)); + } + bus->state = I2C_IDLE; +} + + /* EOB: a master End Of Busy (meaning STOP completed) */ +static void npcm_i2c_irq_handle_eob(struct npcm_i2c *bus) +{ + npcm_i2c_eob_int(bus, false); + bus->state = I2C_IDLE; + npcm_i2c_callback(bus, bus->stop_ind, bus->rd_ind); +} + +/* Address sent and requested stall occurred (Master mode) */ +static void npcm_i2c_irq_handle_stall_after_start(struct npcm_i2c *bus) +{ + if (npcm_i2c_is_quick(bus)) { + bus->state = I2C_STOP_PENDING; + bus->stop_ind = I2C_MASTER_DONE_IND; + npcm_i2c_eob_int(bus, true); + npcm_i2c_master_stop(bus); + } else if ((bus->rd_size == 1) && !bus->read_block_use) { + /* + * Receiving one byte only - set NACK after ensuring + * slave ACKed the address byte. + */ + npcm_i2c_nack(bus); + } + + /* Reset stall-after-address-byte */ + npcm_i2c_stall_after_start(bus, false); + + /* Clear stall only after setting STOP */ + iowrite8(NPCM_I2CST_STASTR, bus->reg + NPCM_I2CST); +} + +/* SDA status is set - TX or RX, master */ +static void npcm_i2c_irq_handle_sda(struct npcm_i2c *bus, u8 i2cst) +{ + u8 fif_cts; + + if (!npcm_i2c_is_master(bus)) + return; + + if (bus->state == I2C_IDLE) { + bus->stop_ind = I2C_WAKE_UP_IND; + + if (npcm_i2c_is_quick(bus) || bus->read_block_use) + /* + * Need to stall after successful + * completion of sending address byte + */ + npcm_i2c_stall_after_start(bus, true); + else + npcm_i2c_stall_after_start(bus, false); + + /* + * Receiving one byte only - stall after successful completion + * of sending address byte If we NACK here, and slave doesn't + * ACK the address, we might unintentionally NACK the next + * multi-byte read + */ + if (bus->wr_size == 0 && bus->rd_size == 1) + npcm_i2c_stall_after_start(bus, true); + + /* Initiate I2C master tx */ + + /* select bank 1 for FIFO regs */ + npcm_i2c_select_bank(bus, I2C_BANK_1); + + fif_cts = ioread8(bus->reg + NPCM_I2CFIF_CTS); + fif_cts = fif_cts & ~NPCM_I2CFIF_CTS_SLVRSTR; + + /* clear FIFO and relevant status bits. */ + fif_cts = fif_cts | NPCM_I2CFIF_CTS_CLR_FIFO; + iowrite8(fif_cts, bus->reg + NPCM_I2CFIF_CTS); + + /* re-enable */ + fif_cts = fif_cts | NPCM_I2CFIF_CTS_RXF_TXE; + iowrite8(fif_cts, bus->reg + NPCM_I2CFIF_CTS); + + /* + * Configure the FIFO threshold: + * according to the needed # of bytes to read. + * Note: due to HW limitation can't config the rx fifo before it + * got and ACK on the restart. LAST bit will not be reset unless + * RX completed. It will stay set on the next tx. + */ + if (bus->wr_size) + npcm_i2c_set_fifo(bus, -1, bus->wr_size); + else + npcm_i2c_set_fifo(bus, bus->rd_size, -1); + + bus->state = I2C_OPER_STARTED; + + if (npcm_i2c_is_quick(bus) || bus->wr_size) + npcm_i2c_wr_byte(bus, bus->dest_addr); + else + npcm_i2c_wr_byte(bus, bus->dest_addr | BIT(0)); + /* SDA interrupt, after start\restart */ + } else { + if (NPCM_I2CST_XMIT & i2cst) { + bus->operation = I2C_WRITE_OPER; + npcm_i2c_irq_master_handler_write(bus); + } else { + bus->operation = I2C_READ_OPER; + npcm_i2c_irq_master_handler_read(bus); + } + } +} + +static int npcm_i2c_int_master_handler(struct npcm_i2c *bus) +{ + u8 i2cst; + int ret = -EIO; + + i2cst = ioread8(bus->reg + NPCM_I2CST); + + if (FIELD_GET(NPCM_I2CST_NMATCH, i2cst)) { + npcm_i2c_irq_handle_nmatch(bus); + return 0; + } + /* A NACK has occurred */ + if (FIELD_GET(NPCM_I2CST_NEGACK, i2cst)) { + npcm_i2c_irq_handle_nack(bus); + return 0; + } + + /* Master mode: a Bus Error has been identified */ + if (FIELD_GET(NPCM_I2CST_BER, i2cst)) { + npcm_i2c_irq_handle_ber(bus); + return 0; + } + + /* EOB: a master End Of Busy (meaning STOP completed) */ + if ((FIELD_GET(NPCM_I2CCTL1_EOBINTE, + ioread8(bus->reg + NPCM_I2CCTL1)) == 1) && + (FIELD_GET(NPCM_I2CCST3_EO_BUSY, + ioread8(bus->reg + NPCM_I2CCST3)))) { + npcm_i2c_irq_handle_eob(bus); + return 0; + } + + /* Address sent and requested stall occurred (Master mode) */ + if (FIELD_GET(NPCM_I2CST_STASTR, i2cst)) { + npcm_i2c_irq_handle_stall_after_start(bus); + ret = 0; + } + + /* SDA status is set - TX or RX, master */ + if (FIELD_GET(NPCM_I2CST_SDAST, i2cst) || + (bus->fifo_use && + (npcm_i2c_tx_fifo_empty(bus) || npcm_i2c_rx_fifo_full(bus)))) { + npcm_i2c_irq_handle_sda(bus, i2cst); + ret = 0; + } + + return ret; +} + +/* recovery using TGCLK functionality of the module */ +static int npcm_i2c_recovery_tgclk(struct i2c_adapter *_adap) +{ + u8 val; + u8 fif_cts; + bool done = false; + int status = -ENOTRECOVERABLE; + struct npcm_i2c *bus = container_of(_adap, struct npcm_i2c, adap); + /* Allow 3 bytes (27 toggles) to be read from the slave: */ + int iter = 27; + + if ((npcm_i2c_get_SDA(_adap) == 1) && (npcm_i2c_get_SCL(_adap) == 1)) { + dev_dbg(bus->dev, "bus%d-0x%x recovery skipped, bus not stuck", + bus->num, bus->dest_addr); + npcm_i2c_reset(bus); + return 0; + } + + npcm_i2c_int_enable(bus, false); + npcm_i2c_disable(bus); + npcm_i2c_enable(bus); + iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST); + npcm_i2c_clear_tx_fifo(bus); + npcm_i2c_clear_rx_fifo(bus); + iowrite8(0, bus->reg + NPCM_I2CRXF_CTL); + iowrite8(0, bus->reg + NPCM_I2CTXF_CTL); + npcm_i2c_stall_after_start(bus, false); + + /* select bank 1 for FIFO regs */ + npcm_i2c_select_bank(bus, I2C_BANK_1); + + /* clear FIFO and relevant status bits. */ + fif_cts = ioread8(bus->reg + NPCM_I2CFIF_CTS); + fif_cts &= ~NPCM_I2CFIF_CTS_SLVRSTR; + fif_cts |= NPCM_I2CFIF_CTS_CLR_FIFO; + iowrite8(fif_cts, bus->reg + NPCM_I2CFIF_CTS); + npcm_i2c_set_fifo(bus, -1, 0); + + /* Repeat the following sequence until SDA is released */ + do { + /* Issue a single SCL toggle */ + iowrite8(NPCM_I2CCST_TGSCL, bus->reg + NPCM_I2CCST); + usleep_range(20, 30); + /* If SDA line is inactive (high), stop */ + if (npcm_i2c_get_SDA(_adap)) { + done = true; + status = 0; + } + } while (!done && iter--); + + /* If SDA line is released: send start-addr-stop, to re-sync. */ + if (npcm_i2c_get_SDA(_adap)) { + /* Send an address byte in write direction: */ + npcm_i2c_wr_byte(bus, bus->dest_addr); + npcm_i2c_master_start(bus); + /* Wait until START condition is sent */ + status = readx_poll_timeout(npcm_i2c_get_SCL, _adap, val, !val, + 20, 200); + /* If START condition was sent */ + if (npcm_i2c_is_master(bus) > 0) { + usleep_range(20, 30); + npcm_i2c_master_stop(bus); + usleep_range(200, 500); + } + } + npcm_i2c_reset(bus); + npcm_i2c_int_enable(bus, true); + + if ((npcm_i2c_get_SDA(_adap) == 1) && (npcm_i2c_get_SCL(_adap) == 1)) + status = 0; + else + status = -ENOTRECOVERABLE; + if (status) { + if (bus->rec_fail_cnt < ULLONG_MAX) + bus->rec_fail_cnt++; + } else { + if (bus->rec_succ_cnt < ULLONG_MAX) + bus->rec_succ_cnt++; + } + return status; +} + +/* recovery using bit banging functionality of the module */ +static void npcm_i2c_recovery_init(struct i2c_adapter *_adap) +{ + struct npcm_i2c *bus = container_of(_adap, struct npcm_i2c, adap); + struct i2c_bus_recovery_info *rinfo = &bus->rinfo; + + rinfo->recover_bus = npcm_i2c_recovery_tgclk; + + /* + * npcm i2c HW allows direct reading of SCL and SDA. + * However, it does not support setting SCL and SDA directly. + * The recovery function can toggle SCL when SDA is low (but not set) + * Getter functions used internally, and can be used externally. + */ + rinfo->get_scl = npcm_i2c_get_SCL; + rinfo->get_sda = npcm_i2c_get_SDA; + _adap->bus_recovery_info = rinfo; +} + +/* SCLFRQ min/max field values */ +#define SCLFRQ_MIN 10 +#define SCLFRQ_MAX 511 +#define clk_coef(freq, mul) DIV_ROUND_UP((freq) * (mul), 1000000) + +/* + * npcm_i2c_init_clk: init HW timing parameters. + * NPCM7XX i2c module timing parameters are dependent on module core clk (APB) + * and bus frequency. + * 100kHz bus requires tSCL = 4 * SCLFRQ * tCLK. LT and HT are symmetric. + * 400kHz bus requires asymmetric HT and LT. A different equation is recommended + * by the HW designer, given core clock range (equations in comments below). + * + */ +static int npcm_i2c_init_clk(struct npcm_i2c *bus, u32 bus_freq_hz) +{ + u32 k1 = 0; + u32 k2 = 0; + u8 dbnct = 0; + u32 sclfrq = 0; + u8 hldt = 7; + u8 fast_mode = 0; + u32 src_clk_khz; + u32 bus_freq_khz; + + src_clk_khz = bus->apb_clk / 1000; + bus_freq_khz = bus_freq_hz / 1000; + bus->bus_freq = bus_freq_hz; + + /* 100KHz and below: */ + if (bus_freq_hz <= I2C_MAX_STANDARD_MODE_FREQ) { + sclfrq = src_clk_khz / (bus_freq_khz * 4); + + if (sclfrq < SCLFRQ_MIN || sclfrq > SCLFRQ_MAX) + return -EDOM; + + if (src_clk_khz >= 40000) + hldt = 17; + else if (src_clk_khz >= 12500) + hldt = 15; + else + hldt = 7; + } + + /* 400KHz: */ + else if (bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ) { + sclfrq = 0; + fast_mode = I2CCTL3_400K_MODE; + + if (src_clk_khz < 7500) + /* 400KHZ cannot be supported for core clock < 7.5MHz */ + return -EDOM; + + else if (src_clk_khz >= 50000) { + k1 = 80; + k2 = 48; + hldt = 12; + dbnct = 7; + } + + /* Master or Slave with frequency > 25MHz */ + else if (src_clk_khz > 25000) { + hldt = clk_coef(src_clk_khz, 300) + 7; + k1 = clk_coef(src_clk_khz, 1600); + k2 = clk_coef(src_clk_khz, 900); + } + } + + /* 1MHz: */ + else if (bus_freq_hz <= I2C_MAX_FAST_MODE_PLUS_FREQ) { + sclfrq = 0; + fast_mode = I2CCTL3_400K_MODE; + + /* 1MHZ cannot be supported for core clock < 24 MHz */ + if (src_clk_khz < 24000) + return -EDOM; + + k1 = clk_coef(src_clk_khz, 620); + k2 = clk_coef(src_clk_khz, 380); + + /* Core clk > 40 MHz */ + if (src_clk_khz > 40000) { + /* + * Set HLDT: + * SDA hold time: (HLDT-7) * T(CLK) >= 120 + * HLDT = 120/T(CLK) + 7 = 120 * FREQ(CLK) + 7 + */ + hldt = clk_coef(src_clk_khz, 120) + 7; + } else { + hldt = 7; + dbnct = 2; + } + } + + /* Frequency larger than 1 MHz is not supported */ + else + return -EINVAL; + + if (bus_freq_hz >= I2C_MAX_FAST_MODE_FREQ) { + k1 = round_up(k1, 2); + k2 = round_up(k2 + 1, 2); + if (k1 < SCLFRQ_MIN || k1 > SCLFRQ_MAX || + k2 < SCLFRQ_MIN || k2 > SCLFRQ_MAX) + return -EDOM; + } + + /* write sclfrq value. bits [6:0] are in I2CCTL2 reg */ + iowrite8(FIELD_PREP(I2CCTL2_SCLFRQ6_0, sclfrq & 0x7F), + bus->reg + NPCM_I2CCTL2); + + /* bits [8:7] are in I2CCTL3 reg */ + iowrite8(fast_mode | FIELD_PREP(I2CCTL3_SCLFRQ8_7, (sclfrq >> 7) & 0x3), + bus->reg + NPCM_I2CCTL3); + + /* Select Bank 0 to access NPCM_I2CCTL4/NPCM_I2CCTL5 */ + npcm_i2c_select_bank(bus, I2C_BANK_0); + + if (bus_freq_hz >= I2C_MAX_FAST_MODE_FREQ) { + /* + * Set SCL Low/High Time: + * k1 = 2 * SCLLT7-0 -> Low Time = k1 / 2 + * k2 = 2 * SCLLT7-0 -> High Time = k2 / 2 + */ + iowrite8(k1 / 2, bus->reg + NPCM_I2CSCLLT); + iowrite8(k2 / 2, bus->reg + NPCM_I2CSCLHT); + + iowrite8(dbnct, bus->reg + NPCM_I2CCTL5); + } + + iowrite8(hldt, bus->reg + NPCM_I2CCTL4); + + /* Return to Bank 1, and stay there by default: */ + npcm_i2c_select_bank(bus, I2C_BANK_1); + + return 0; +} + +static int npcm_i2c_init_module(struct npcm_i2c *bus, enum i2c_mode mode, + u32 bus_freq_hz) +{ + u8 val; + int ret; + + /* Check whether module already enabled or frequency is out of bounds */ + if ((bus->state != I2C_DISABLE && bus->state != I2C_IDLE) || + bus_freq_hz < I2C_FREQ_MIN_HZ || bus_freq_hz > I2C_FREQ_MAX_HZ) + return -EINVAL; + + npcm_i2c_int_enable(bus, false); + npcm_i2c_disable(bus); + + /* Configure FIFO mode : */ + if (FIELD_GET(I2C_VER_FIFO_EN, ioread8(bus->reg + I2C_VER))) { + bus->fifo_use = true; + npcm_i2c_select_bank(bus, I2C_BANK_0); + val = ioread8(bus->reg + NPCM_I2CFIF_CTL); + val |= NPCM_I2CFIF_CTL_FIFO_EN; + iowrite8(val, bus->reg + NPCM_I2CFIF_CTL); + npcm_i2c_select_bank(bus, I2C_BANK_1); + } else { + bus->fifo_use = false; + } + + /* Configure I2C module clock frequency */ + ret = npcm_i2c_init_clk(bus, bus_freq_hz); + if (ret) { + dev_err(bus->dev, "npcm_i2c_init_clk failed\n"); + return ret; + } + + /* Enable module (before configuring CTL1) */ + npcm_i2c_enable(bus); + bus->state = I2C_IDLE; + val = ioread8(bus->reg + NPCM_I2CCTL1); + val = (val | NPCM_I2CCTL1_NMINTE) & ~NPCM_I2CCTL1_RWS; + iowrite8(val, bus->reg + NPCM_I2CCTL1); + + npcm_i2c_reset(bus); + + /* Check HW is OK: SDA and SCL should be high at this point. */ + if ((npcm_i2c_get_SDA(&bus->adap) == 0) || (npcm_i2c_get_SCL(&bus->adap) == 0)) { + dev_err(bus->dev, "I2C%d init fail: lines are low\n", bus->num); + dev_err(bus->dev, "SDA=%d SCL=%d\n", npcm_i2c_get_SDA(&bus->adap), + npcm_i2c_get_SCL(&bus->adap)); + return -ENXIO; + } + + npcm_i2c_int_enable(bus, true); + return 0; +} + +static int __npcm_i2c_init(struct npcm_i2c *bus, struct platform_device *pdev) +{ + u32 clk_freq_hz; + int ret; + + /* Initialize the internal data structures */ + bus->state = I2C_DISABLE; + bus->master_or_slave = I2C_SLAVE; + bus->int_time_stamp = 0; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + bus->slave = NULL; +#endif + + ret = device_property_read_u32(&pdev->dev, "clock-frequency", + &clk_freq_hz); + if (ret) { + dev_info(&pdev->dev, "Could not read clock-frequency property"); + clk_freq_hz = I2C_MAX_STANDARD_MODE_FREQ; + } + + ret = npcm_i2c_init_module(bus, I2C_MASTER, clk_freq_hz); + if (ret) { + dev_err(&pdev->dev, "npcm_i2c_init_module failed\n"); + return ret; + } + + return 0; +} + +static irqreturn_t npcm_i2c_bus_irq(int irq, void *dev_id) +{ + struct npcm_i2c *bus = dev_id; + + if (npcm_i2c_is_master(bus)) + bus->master_or_slave = I2C_MASTER; + + if (bus->master_or_slave == I2C_MASTER) { + bus->int_time_stamp = jiffies; + if (!npcm_i2c_int_master_handler(bus)) + return IRQ_HANDLED; + } +#if IS_ENABLED(CONFIG_I2C_SLAVE) + if (bus->slave) { + bus->master_or_slave = I2C_SLAVE; + if (npcm_i2c_int_slave_handler(bus)) + return IRQ_HANDLED; + } +#endif + /* Clear status bits for spurious interrupts */ + npcm_i2c_clear_master_status(bus); + + return IRQ_HANDLED; +} + +static bool npcm_i2c_master_start_xmit(struct npcm_i2c *bus, + u8 slave_addr, u16 nwrite, u16 nread, + u8 *write_data, u8 *read_data, + bool use_PEC, bool use_read_block) +{ + if (bus->state != I2C_IDLE) { + bus->cmd_err = -EBUSY; + return false; + } + bus->dest_addr = slave_addr << 1; + bus->wr_buf = write_data; + bus->wr_size = nwrite; + bus->wr_ind = 0; + bus->rd_buf = read_data; + bus->rd_size = nread; + bus->rd_ind = 0; + bus->PEC_use = 0; + + /* for tx PEC is appended to buffer from i2c IF. PEC flag is ignored */ + if (nread) + bus->PEC_use = use_PEC; + + bus->read_block_use = use_read_block; + if (nread && !nwrite) + bus->operation = I2C_READ_OPER; + else + bus->operation = I2C_WRITE_OPER; + if (bus->fifo_use) { + u8 i2cfif_cts; + + npcm_i2c_select_bank(bus, I2C_BANK_1); + /* clear FIFO and relevant status bits. */ + i2cfif_cts = ioread8(bus->reg + NPCM_I2CFIF_CTS); + i2cfif_cts &= ~NPCM_I2CFIF_CTS_SLVRSTR; + i2cfif_cts |= NPCM_I2CFIF_CTS_CLR_FIFO; + iowrite8(i2cfif_cts, bus->reg + NPCM_I2CFIF_CTS); + } + + bus->state = I2C_IDLE; + npcm_i2c_stall_after_start(bus, true); + npcm_i2c_master_start(bus); + return true; +} + +static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct npcm_i2c *bus = container_of(adap, struct npcm_i2c, adap); + struct i2c_msg *msg0, *msg1; + unsigned long time_left, flags; + u16 nwrite, nread; + u8 *write_data, *read_data; + u8 slave_addr; + unsigned long timeout; + bool read_block = false; + bool read_PEC = false; + u8 bus_busy; + unsigned long timeout_usec; + + if (bus->state == I2C_DISABLE) { + dev_err(bus->dev, "I2C%d module is disabled", bus->num); + return -EINVAL; + } + + msg0 = &msgs[0]; + slave_addr = msg0->addr; + if (msg0->flags & I2C_M_RD) { /* read */ + nwrite = 0; + write_data = NULL; + read_data = msg0->buf; + if (msg0->flags & I2C_M_RECV_LEN) { + nread = 1; + read_block = true; + if (msg0->flags & I2C_CLIENT_PEC) + read_PEC = true; + } else { + nread = msg0->len; + } + } else { /* write */ + nwrite = msg0->len; + write_data = msg0->buf; + nread = 0; + read_data = NULL; + if (num == 2) { + msg1 = &msgs[1]; + read_data = msg1->buf; + if (msg1->flags & I2C_M_RECV_LEN) { + nread = 1; + read_block = true; + if (msg1->flags & I2C_CLIENT_PEC) + read_PEC = true; + } else { + nread = msg1->len; + read_block = false; + } + } + } + + /* + * Adaptive TimeOut: estimated time in usec + 100% margin: + * 2: double the timeout for clock stretching case + * 9: bits per transaction (including the ack/nack) + */ + timeout_usec = (2 * 9 * USEC_PER_SEC / bus->bus_freq) * (2 + nread + nwrite); + timeout = max_t(unsigned long, bus->adap.timeout, usecs_to_jiffies(timeout_usec)); + if (nwrite >= 32 * 1024 || nread >= 32 * 1024) { + dev_err(bus->dev, "i2c%d buffer too big\n", bus->num); + return -EINVAL; + } + + time_left = jiffies + timeout + 1; + do { + /* + * we must clear slave address immediately when the bus is not + * busy, so we spinlock it, but we don't keep the lock for the + * entire while since it is too long. + */ + spin_lock_irqsave(&bus->lock, flags); + bus_busy = ioread8(bus->reg + NPCM_I2CCST) & NPCM_I2CCST_BB; +#if IS_ENABLED(CONFIG_I2C_SLAVE) + if (!bus_busy && bus->slave) + iowrite8((bus->slave->addr & 0x7F), + bus->reg + NPCM_I2CADDR1); +#endif + spin_unlock_irqrestore(&bus->lock, flags); + + } while (time_is_after_jiffies(time_left) && bus_busy); + + if (bus_busy) { + iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST); + npcm_i2c_reset(bus); + i2c_recover_bus(adap); + return -EAGAIN; + } + + npcm_i2c_init_params(bus); + bus->dest_addr = slave_addr; + bus->msgs = msgs; + bus->msgs_num = num; + bus->cmd_err = 0; + bus->read_block_use = read_block; + + reinit_completion(&bus->cmd_complete); + + npcm_i2c_int_enable(bus, true); + + if (npcm_i2c_master_start_xmit(bus, slave_addr, nwrite, nread, + write_data, read_data, read_PEC, + read_block)) { + time_left = wait_for_completion_timeout(&bus->cmd_complete, + timeout); + + if (time_left == 0) { + if (bus->timeout_cnt < ULLONG_MAX) + bus->timeout_cnt++; + if (bus->master_or_slave == I2C_MASTER) { + i2c_recover_bus(adap); + bus->cmd_err = -EIO; + bus->state = I2C_IDLE; + } + } + } + + /* if there was BER, check if need to recover the bus: */ + if (bus->cmd_err == -EAGAIN) + bus->cmd_err = i2c_recover_bus(adap); + + /* + * After any type of error, check if LAST bit is still set, + * due to a HW issue. + * It cannot be cleared without resetting the module. + */ + else if (bus->cmd_err && + (bus->data->rxf_ctl_last_pec & ioread8(bus->reg + NPCM_I2CRXF_CTL))) + npcm_i2c_reset(bus); + + /* After any xfer, successful or not, stall and EOB must be disabled */ + npcm_i2c_stall_after_start(bus, false); + npcm_i2c_eob_int(bus, false); + +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* reenable slave if it was enabled */ + if (bus->slave) + iowrite8((bus->slave->addr & 0x7F) | NPCM_I2CADDR_SAEN, + bus->reg + NPCM_I2CADDR1); +#else + npcm_i2c_int_enable(bus, false); +#endif + return bus->cmd_err; +} + +static u32 npcm_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | + I2C_FUNC_SMBUS_EMUL | + I2C_FUNC_SMBUS_BLOCK_DATA | + I2C_FUNC_SMBUS_PEC | + I2C_FUNC_SLAVE; +} + +static const struct i2c_adapter_quirks npcm_i2c_quirks = { + .max_read_len = 32768, + .max_write_len = 32768, + .flags = I2C_AQ_COMB_WRITE_THEN_READ, +}; + +static const struct i2c_algorithm npcm_i2c_algo = { + .master_xfer = npcm_i2c_master_xfer, + .functionality = npcm_i2c_functionality, +#if IS_ENABLED(CONFIG_I2C_SLAVE) + .reg_slave = npcm_i2c_reg_slave, + .unreg_slave = npcm_i2c_unreg_slave, +#endif +}; + +/* i2c debugfs directory: used to keep health monitor of i2c devices */ +static struct dentry *npcm_i2c_debugfs_dir; + +static void npcm_i2c_init_debugfs(struct platform_device *pdev, + struct npcm_i2c *bus) +{ + struct dentry *d; + + if (!npcm_i2c_debugfs_dir) + return; + d = debugfs_create_dir(dev_name(&pdev->dev), npcm_i2c_debugfs_dir); + if (IS_ERR_OR_NULL(d)) + return; + debugfs_create_u64("ber_cnt", 0444, d, &bus->ber_cnt); + debugfs_create_u64("nack_cnt", 0444, d, &bus->nack_cnt); + debugfs_create_u64("rec_succ_cnt", 0444, d, &bus->rec_succ_cnt); + debugfs_create_u64("rec_fail_cnt", 0444, d, &bus->rec_fail_cnt); + debugfs_create_u64("timeout_cnt", 0444, d, &bus->timeout_cnt); + debugfs_create_u64("tx_complete_cnt", 0444, d, &bus->tx_complete_cnt); + + bus->debugfs = d; +} + +static int npcm_i2c_probe_bus(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + static struct regmap *gcr_regmap; + struct device *dev = &pdev->dev; + struct i2c_adapter *adap; + struct npcm_i2c *bus; + struct clk *i2c_clk; + int irq; + int ret; + + bus = devm_kzalloc(&pdev->dev, sizeof(*bus), GFP_KERNEL); + if (!bus) + return -ENOMEM; + + bus->dev = &pdev->dev; + + bus->data = of_device_get_match_data(dev); + if (!bus->data) { + dev_err(dev, "OF data missing\n"); + return -EINVAL; + } + + bus->num = of_alias_get_id(pdev->dev.of_node, "i2c"); + /* core clk must be acquired to calculate module timing settings */ + i2c_clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(i2c_clk)) + return PTR_ERR(i2c_clk); + bus->apb_clk = clk_get_rate(i2c_clk); + + gcr_regmap = syscon_regmap_lookup_by_phandle(np, "nuvoton,sys-mgr"); + if (IS_ERR(gcr_regmap)) + gcr_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-gcr"); + + if (IS_ERR(gcr_regmap)) + return PTR_ERR(gcr_regmap); + regmap_write(gcr_regmap, NPCM_I2CSEGCTL, bus->data->segctl_init_val); + + bus->reg = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(bus->reg)) + return PTR_ERR(bus->reg); + + spin_lock_init(&bus->lock); + init_completion(&bus->cmd_complete); + + adap = &bus->adap; + adap->owner = THIS_MODULE; + adap->retries = 3; + adap->timeout = msecs_to_jiffies(35); + adap->algo = &npcm_i2c_algo; + adap->quirks = &npcm_i2c_quirks; + adap->algo_data = bus; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + adap->nr = pdev->id; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + ret = devm_request_irq(bus->dev, irq, npcm_i2c_bus_irq, 0, + dev_name(bus->dev), bus); + if (ret) + return ret; + + ret = __npcm_i2c_init(bus, pdev); + if (ret) + return ret; + + npcm_i2c_recovery_init(adap); + + i2c_set_adapdata(adap, bus); + + snprintf(bus->adap.name, sizeof(bus->adap.name), "npcm_i2c_%d", + bus->num); + ret = i2c_add_numbered_adapter(&bus->adap); + if (ret) + return ret; + + platform_set_drvdata(pdev, bus); + npcm_i2c_init_debugfs(pdev, bus); + return 0; +} + +static void npcm_i2c_remove_bus(struct platform_device *pdev) +{ + unsigned long lock_flags; + struct npcm_i2c *bus = platform_get_drvdata(pdev); + + debugfs_remove_recursive(bus->debugfs); + spin_lock_irqsave(&bus->lock, lock_flags); + npcm_i2c_disable(bus); + spin_unlock_irqrestore(&bus->lock, lock_flags); + i2c_del_adapter(&bus->adap); +} + +static const struct of_device_id npcm_i2c_bus_of_table[] = { + { .compatible = "nuvoton,npcm750-i2c", .data = &npxm7xx_i2c_data }, + { .compatible = "nuvoton,npcm845-i2c", .data = &npxm8xx_i2c_data }, + {} +}; +MODULE_DEVICE_TABLE(of, npcm_i2c_bus_of_table); + +static struct platform_driver npcm_i2c_bus_driver = { + .probe = npcm_i2c_probe_bus, + .remove_new = npcm_i2c_remove_bus, + .driver = { + .name = "nuvoton-i2c", + .of_match_table = npcm_i2c_bus_of_table, + } +}; + +static int __init npcm_i2c_init(void) +{ + int ret; + + npcm_i2c_debugfs_dir = debugfs_create_dir("npcm_i2c", NULL); + + ret = platform_driver_register(&npcm_i2c_bus_driver); + if (ret) { + debugfs_remove_recursive(npcm_i2c_debugfs_dir); + return ret; + } + + return 0; +} +module_init(npcm_i2c_init); + +static void __exit npcm_i2c_exit(void) +{ + platform_driver_unregister(&npcm_i2c_bus_driver); + debugfs_remove_recursive(npcm_i2c_debugfs_dir); +} +module_exit(npcm_i2c_exit); + +MODULE_AUTHOR("Avi Fishman <avi.fishman@gmail.com>"); +MODULE_AUTHOR("Tali Perry <tali.perry@nuvoton.com>"); +MODULE_AUTHOR("Tyrone Ting <kfting@nuvoton.com>"); +MODULE_DESCRIPTION("Nuvoton I2C Bus Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-nvidia-gpu.c b/drivers/i2c/busses/i2c-nvidia-gpu.c new file mode 100644 index 000000000..26622d24b --- /dev/null +++ b/drivers/i2c/busses/i2c-nvidia-gpu.c @@ -0,0 +1,377 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Nvidia GPU I2C controller Driver + * + * Copyright (C) 2018 NVIDIA Corporation. All rights reserved. + * Author: Ajay Gupta <ajayg@nvidia.com> + */ +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> +#include <linux/power_supply.h> + +#include <asm/unaligned.h> + +#include "i2c-ccgx-ucsi.h" + +/* I2C definitions */ +#define I2C_MST_CNTL 0x00 +#define I2C_MST_CNTL_GEN_START BIT(0) +#define I2C_MST_CNTL_GEN_STOP BIT(1) +#define I2C_MST_CNTL_CMD_READ (1 << 2) +#define I2C_MST_CNTL_CMD_WRITE (2 << 2) +#define I2C_MST_CNTL_BURST_SIZE_SHIFT 6 +#define I2C_MST_CNTL_GEN_NACK BIT(28) +#define I2C_MST_CNTL_STATUS GENMASK(30, 29) +#define I2C_MST_CNTL_STATUS_OKAY (0 << 29) +#define I2C_MST_CNTL_STATUS_NO_ACK (1 << 29) +#define I2C_MST_CNTL_STATUS_TIMEOUT (2 << 29) +#define I2C_MST_CNTL_STATUS_BUS_BUSY (3 << 29) +#define I2C_MST_CNTL_CYCLE_TRIGGER BIT(31) + +#define I2C_MST_ADDR 0x04 + +#define I2C_MST_I2C0_TIMING 0x08 +#define I2C_MST_I2C0_TIMING_SCL_PERIOD_100KHZ 0x10e +#define I2C_MST_I2C0_TIMING_TIMEOUT_CLK_CNT 16 +#define I2C_MST_I2C0_TIMING_TIMEOUT_CLK_CNT_MAX 255 +#define I2C_MST_I2C0_TIMING_TIMEOUT_CHECK BIT(24) + +#define I2C_MST_DATA 0x0c + +#define I2C_MST_HYBRID_PADCTL 0x20 +#define I2C_MST_HYBRID_PADCTL_MODE_I2C BIT(0) +#define I2C_MST_HYBRID_PADCTL_I2C_SCL_INPUT_RCV BIT(14) +#define I2C_MST_HYBRID_PADCTL_I2C_SDA_INPUT_RCV BIT(15) + +struct gpu_i2c_dev { + struct device *dev; + void __iomem *regs; + struct i2c_adapter adapter; + struct i2c_board_info *gpu_ccgx_ucsi; + struct i2c_client *ccgx_client; +}; + +static void gpu_enable_i2c_bus(struct gpu_i2c_dev *i2cd) +{ + u32 val; + + /* enable I2C */ + val = readl(i2cd->regs + I2C_MST_HYBRID_PADCTL); + val |= I2C_MST_HYBRID_PADCTL_MODE_I2C | + I2C_MST_HYBRID_PADCTL_I2C_SCL_INPUT_RCV | + I2C_MST_HYBRID_PADCTL_I2C_SDA_INPUT_RCV; + writel(val, i2cd->regs + I2C_MST_HYBRID_PADCTL); + + /* enable 100KHZ mode */ + val = I2C_MST_I2C0_TIMING_SCL_PERIOD_100KHZ; + val |= (I2C_MST_I2C0_TIMING_TIMEOUT_CLK_CNT_MAX + << I2C_MST_I2C0_TIMING_TIMEOUT_CLK_CNT); + val |= I2C_MST_I2C0_TIMING_TIMEOUT_CHECK; + writel(val, i2cd->regs + I2C_MST_I2C0_TIMING); +} + +static int gpu_i2c_check_status(struct gpu_i2c_dev *i2cd) +{ + u32 val; + int ret; + + ret = readl_poll_timeout(i2cd->regs + I2C_MST_CNTL, val, + !(val & I2C_MST_CNTL_CYCLE_TRIGGER) || + (val & I2C_MST_CNTL_STATUS) != I2C_MST_CNTL_STATUS_BUS_BUSY, + 500, 1000 * USEC_PER_MSEC); + + if (ret) { + dev_err(i2cd->dev, "i2c timeout error %x\n", val); + return -ETIMEDOUT; + } + + val = readl(i2cd->regs + I2C_MST_CNTL); + switch (val & I2C_MST_CNTL_STATUS) { + case I2C_MST_CNTL_STATUS_OKAY: + return 0; + case I2C_MST_CNTL_STATUS_NO_ACK: + return -ENXIO; + case I2C_MST_CNTL_STATUS_TIMEOUT: + return -ETIMEDOUT; + default: + return 0; + } +} + +static int gpu_i2c_read(struct gpu_i2c_dev *i2cd, u8 *data, u16 len) +{ + int status; + u32 val; + + val = I2C_MST_CNTL_GEN_START | I2C_MST_CNTL_CMD_READ | + (len << I2C_MST_CNTL_BURST_SIZE_SHIFT) | + I2C_MST_CNTL_CYCLE_TRIGGER | I2C_MST_CNTL_GEN_NACK; + writel(val, i2cd->regs + I2C_MST_CNTL); + + status = gpu_i2c_check_status(i2cd); + if (status < 0) + return status; + + val = readl(i2cd->regs + I2C_MST_DATA); + switch (len) { + case 1: + data[0] = val; + break; + case 2: + put_unaligned_be16(val, data); + break; + case 3: + put_unaligned_be24(val, data); + break; + case 4: + put_unaligned_be32(val, data); + break; + default: + break; + } + return status; +} + +static int gpu_i2c_start(struct gpu_i2c_dev *i2cd) +{ + writel(I2C_MST_CNTL_GEN_START, i2cd->regs + I2C_MST_CNTL); + return gpu_i2c_check_status(i2cd); +} + +static int gpu_i2c_stop(struct gpu_i2c_dev *i2cd) +{ + writel(I2C_MST_CNTL_GEN_STOP, i2cd->regs + I2C_MST_CNTL); + return gpu_i2c_check_status(i2cd); +} + +static int gpu_i2c_write(struct gpu_i2c_dev *i2cd, u8 data) +{ + u32 val; + + writel(data, i2cd->regs + I2C_MST_DATA); + + val = I2C_MST_CNTL_CMD_WRITE | (1 << I2C_MST_CNTL_BURST_SIZE_SHIFT); + writel(val, i2cd->regs + I2C_MST_CNTL); + + return gpu_i2c_check_status(i2cd); +} + +static int gpu_i2c_master_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct gpu_i2c_dev *i2cd = i2c_get_adapdata(adap); + int status, status2; + bool send_stop = true; + int i, j; + + /* + * The controller supports maximum 4 byte read due to known + * limitation of sending STOP after every read. + */ + pm_runtime_get_sync(i2cd->dev); + for (i = 0; i < num; i++) { + if (msgs[i].flags & I2C_M_RD) { + /* program client address before starting read */ + writel(msgs[i].addr, i2cd->regs + I2C_MST_ADDR); + /* gpu_i2c_read has implicit start */ + status = gpu_i2c_read(i2cd, msgs[i].buf, msgs[i].len); + if (status < 0) + goto exit; + } else { + u8 addr = i2c_8bit_addr_from_msg(msgs + i); + + status = gpu_i2c_start(i2cd); + if (status < 0) { + if (i == 0) + send_stop = false; + goto exit; + } + + status = gpu_i2c_write(i2cd, addr); + if (status < 0) + goto exit; + + for (j = 0; j < msgs[i].len; j++) { + status = gpu_i2c_write(i2cd, msgs[i].buf[j]); + if (status < 0) + goto exit; + } + } + } + send_stop = false; + status = gpu_i2c_stop(i2cd); + if (status < 0) + goto exit; + + status = i; +exit: + if (send_stop) { + status2 = gpu_i2c_stop(i2cd); + if (status2 < 0) + dev_err(i2cd->dev, "i2c stop failed %d\n", status2); + } + pm_runtime_mark_last_busy(i2cd->dev); + pm_runtime_put_autosuspend(i2cd->dev); + return status; +} + +static const struct i2c_adapter_quirks gpu_i2c_quirks = { + .max_read_len = 4, + .max_comb_2nd_msg_len = 4, + .flags = I2C_AQ_COMB_WRITE_THEN_READ, +}; + +static u32 gpu_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm gpu_i2c_algorithm = { + .master_xfer = gpu_i2c_master_xfer, + .functionality = gpu_i2c_functionality, +}; + +/* + * This driver is for Nvidia GPU cards with USB Type-C interface. + * We want to identify the cards using vendor ID and class code only + * to avoid dependency of adding product id for any new card which + * requires this driver. + * Currently there is no class code defined for UCSI device over PCI + * so using UNKNOWN class for now and it will be updated when UCSI + * over PCI gets a class code. + * There is no other NVIDIA cards with UNKNOWN class code. Even if the + * driver gets loaded for an undesired card then eventually i2c_read() + * (initiated from UCSI i2c_client) will timeout or UCSI commands will + * timeout. + */ +#define PCI_CLASS_SERIAL_UNKNOWN 0x0c80 +static const struct pci_device_id gpu_i2c_ids[] = { + { PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, + PCI_CLASS_SERIAL_UNKNOWN << 8, 0xffffff00}, + { } +}; +MODULE_DEVICE_TABLE(pci, gpu_i2c_ids); + +static const struct property_entry ccgx_props[] = { + /* Use FW built for NVIDIA GPU only */ + PROPERTY_ENTRY_STRING("firmware-name", "nvidia,gpu"), + /* USB-C doesn't power the system */ + PROPERTY_ENTRY_U8("scope", POWER_SUPPLY_SCOPE_DEVICE), + { } +}; + +static const struct software_node ccgx_node = { + .properties = ccgx_props, +}; + +static int gpu_i2c_probe(struct pci_dev *pdev, const struct pci_device_id *id) +{ + struct device *dev = &pdev->dev; + struct gpu_i2c_dev *i2cd; + int status; + + i2cd = devm_kzalloc(dev, sizeof(*i2cd), GFP_KERNEL); + if (!i2cd) + return -ENOMEM; + + i2cd->dev = dev; + dev_set_drvdata(dev, i2cd); + + status = pcim_enable_device(pdev); + if (status < 0) + return dev_err_probe(dev, status, "pcim_enable_device failed\n"); + + pci_set_master(pdev); + + i2cd->regs = pcim_iomap(pdev, 0, 0); + if (!i2cd->regs) + return dev_err_probe(dev, -ENOMEM, "pcim_iomap failed\n"); + + status = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI); + if (status < 0) + return dev_err_probe(dev, status, "pci_alloc_irq_vectors err\n"); + + gpu_enable_i2c_bus(i2cd); + + i2c_set_adapdata(&i2cd->adapter, i2cd); + i2cd->adapter.owner = THIS_MODULE; + strscpy(i2cd->adapter.name, "NVIDIA GPU I2C adapter", + sizeof(i2cd->adapter.name)); + i2cd->adapter.algo = &gpu_i2c_algorithm; + i2cd->adapter.quirks = &gpu_i2c_quirks; + i2cd->adapter.dev.parent = dev; + status = i2c_add_adapter(&i2cd->adapter); + if (status < 0) + goto free_irq_vectors; + + i2cd->ccgx_client = i2c_new_ccgx_ucsi(&i2cd->adapter, pdev->irq, &ccgx_node); + if (IS_ERR(i2cd->ccgx_client)) { + status = dev_err_probe(dev, PTR_ERR(i2cd->ccgx_client), "register UCSI failed\n"); + goto del_adapter; + } + + pm_runtime_set_autosuspend_delay(dev, 3000); + pm_runtime_use_autosuspend(dev); + pm_runtime_put_autosuspend(dev); + pm_runtime_allow(dev); + + return 0; + +del_adapter: + i2c_del_adapter(&i2cd->adapter); +free_irq_vectors: + pci_free_irq_vectors(pdev); + return status; +} + +static void gpu_i2c_remove(struct pci_dev *pdev) +{ + struct gpu_i2c_dev *i2cd = pci_get_drvdata(pdev); + + pm_runtime_get_noresume(i2cd->dev); + i2c_del_adapter(&i2cd->adapter); + pci_free_irq_vectors(pdev); +} + +#define gpu_i2c_suspend NULL + +static __maybe_unused int gpu_i2c_resume(struct device *dev) +{ + struct gpu_i2c_dev *i2cd = dev_get_drvdata(dev); + + gpu_enable_i2c_bus(i2cd); + /* + * Runtime resume ccgx client so that it can see for any + * connector change event. Old ccg firmware has known + * issue of not triggering interrupt when a device is + * connected to runtime resume the controller. + */ + pm_request_resume(&i2cd->ccgx_client->dev); + return 0; +} + +static UNIVERSAL_DEV_PM_OPS(gpu_i2c_driver_pm, gpu_i2c_suspend, gpu_i2c_resume, + NULL); + +static struct pci_driver gpu_i2c_driver = { + .name = "nvidia-gpu", + .id_table = gpu_i2c_ids, + .probe = gpu_i2c_probe, + .remove = gpu_i2c_remove, + .driver = { + .pm = &gpu_i2c_driver_pm, + }, +}; + +module_pci_driver(gpu_i2c_driver); + +MODULE_AUTHOR("Ajay Gupta <ajayg@nvidia.com>"); +MODULE_DESCRIPTION("Nvidia GPU I2C controller Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c new file mode 100644 index 000000000..e106af83c --- /dev/null +++ b/drivers/i2c/busses/i2c-ocores.c @@ -0,0 +1,792 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * i2c-ocores.c: I2C bus driver for OpenCores I2C controller + * (https://opencores.org/project/i2c/overview) + * + * Peter Korsgaard <peter@korsgaard.com> + * + * Support for the GRLIB port of the controller by + * Andreas Larsson <andreas@gaisler.com> + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/platform_device.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/wait.h> +#include <linux/platform_data/i2c-ocores.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/log2.h> +#include <linux/spinlock.h> +#include <linux/jiffies.h> + +/* + * 'process_lock' exists because ocores_process() and ocores_process_timeout() + * can't run in parallel. + */ +struct ocores_i2c { + void __iomem *base; + int iobase; + u32 reg_shift; + u32 reg_io_width; + unsigned long flags; + wait_queue_head_t wait; + struct i2c_adapter adap; + struct i2c_msg *msg; + int pos; + int nmsgs; + int state; /* see STATE_ */ + spinlock_t process_lock; + struct clk *clk; + int ip_clock_khz; + int bus_clock_khz; + void (*setreg)(struct ocores_i2c *i2c, int reg, u8 value); + u8 (*getreg)(struct ocores_i2c *i2c, int reg); +}; + +/* registers */ +#define OCI2C_PRELOW 0 +#define OCI2C_PREHIGH 1 +#define OCI2C_CONTROL 2 +#define OCI2C_DATA 3 +#define OCI2C_CMD 4 /* write only */ +#define OCI2C_STATUS 4 /* read only, same address as OCI2C_CMD */ + +#define OCI2C_CTRL_IEN 0x40 +#define OCI2C_CTRL_EN 0x80 + +#define OCI2C_CMD_START 0x91 +#define OCI2C_CMD_STOP 0x41 +#define OCI2C_CMD_READ 0x21 +#define OCI2C_CMD_WRITE 0x11 +#define OCI2C_CMD_READ_ACK 0x21 +#define OCI2C_CMD_READ_NACK 0x29 +#define OCI2C_CMD_IACK 0x01 + +#define OCI2C_STAT_IF 0x01 +#define OCI2C_STAT_TIP 0x02 +#define OCI2C_STAT_ARBLOST 0x20 +#define OCI2C_STAT_BUSY 0x40 +#define OCI2C_STAT_NACK 0x80 + +#define STATE_DONE 0 +#define STATE_START 1 +#define STATE_WRITE 2 +#define STATE_READ 3 +#define STATE_ERROR 4 + +#define TYPE_OCORES 0 +#define TYPE_GRLIB 1 + +#define OCORES_FLAG_BROKEN_IRQ BIT(1) /* Broken IRQ for FU540-C000 SoC */ + +static void oc_setreg_8(struct ocores_i2c *i2c, int reg, u8 value) +{ + iowrite8(value, i2c->base + (reg << i2c->reg_shift)); +} + +static void oc_setreg_16(struct ocores_i2c *i2c, int reg, u8 value) +{ + iowrite16(value, i2c->base + (reg << i2c->reg_shift)); +} + +static void oc_setreg_32(struct ocores_i2c *i2c, int reg, u8 value) +{ + iowrite32(value, i2c->base + (reg << i2c->reg_shift)); +} + +static void oc_setreg_16be(struct ocores_i2c *i2c, int reg, u8 value) +{ + iowrite16be(value, i2c->base + (reg << i2c->reg_shift)); +} + +static void oc_setreg_32be(struct ocores_i2c *i2c, int reg, u8 value) +{ + iowrite32be(value, i2c->base + (reg << i2c->reg_shift)); +} + +static inline u8 oc_getreg_8(struct ocores_i2c *i2c, int reg) +{ + return ioread8(i2c->base + (reg << i2c->reg_shift)); +} + +static inline u8 oc_getreg_16(struct ocores_i2c *i2c, int reg) +{ + return ioread16(i2c->base + (reg << i2c->reg_shift)); +} + +static inline u8 oc_getreg_32(struct ocores_i2c *i2c, int reg) +{ + return ioread32(i2c->base + (reg << i2c->reg_shift)); +} + +static inline u8 oc_getreg_16be(struct ocores_i2c *i2c, int reg) +{ + return ioread16be(i2c->base + (reg << i2c->reg_shift)); +} + +static inline u8 oc_getreg_32be(struct ocores_i2c *i2c, int reg) +{ + return ioread32be(i2c->base + (reg << i2c->reg_shift)); +} + +static void oc_setreg_io_8(struct ocores_i2c *i2c, int reg, u8 value) +{ + outb(value, i2c->iobase + reg); +} + +static inline u8 oc_getreg_io_8(struct ocores_i2c *i2c, int reg) +{ + return inb(i2c->iobase + reg); +} + +static inline void oc_setreg(struct ocores_i2c *i2c, int reg, u8 value) +{ + i2c->setreg(i2c, reg, value); +} + +static inline u8 oc_getreg(struct ocores_i2c *i2c, int reg) +{ + return i2c->getreg(i2c, reg); +} + +static void ocores_process(struct ocores_i2c *i2c, u8 stat) +{ + struct i2c_msg *msg = i2c->msg; + unsigned long flags; + + /* + * If we spin here is because we are in timeout, so we are going + * to be in STATE_ERROR. See ocores_process_timeout() + */ + spin_lock_irqsave(&i2c->process_lock, flags); + + if ((i2c->state == STATE_DONE) || (i2c->state == STATE_ERROR)) { + /* stop has been sent */ + oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_IACK); + wake_up(&i2c->wait); + goto out; + } + + /* error? */ + if (stat & OCI2C_STAT_ARBLOST) { + i2c->state = STATE_ERROR; + oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_STOP); + goto out; + } + + if ((i2c->state == STATE_START) || (i2c->state == STATE_WRITE)) { + i2c->state = + (msg->flags & I2C_M_RD) ? STATE_READ : STATE_WRITE; + + if (stat & OCI2C_STAT_NACK) { + i2c->state = STATE_ERROR; + oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_STOP); + goto out; + } + } else { + msg->buf[i2c->pos++] = oc_getreg(i2c, OCI2C_DATA); + } + + /* end of msg? */ + if (i2c->pos == msg->len) { + i2c->nmsgs--; + i2c->msg++; + i2c->pos = 0; + msg = i2c->msg; + + if (i2c->nmsgs) { /* end? */ + /* send start? */ + if (!(msg->flags & I2C_M_NOSTART)) { + u8 addr = i2c_8bit_addr_from_msg(msg); + + i2c->state = STATE_START; + + oc_setreg(i2c, OCI2C_DATA, addr); + oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_START); + goto out; + } + i2c->state = (msg->flags & I2C_M_RD) + ? STATE_READ : STATE_WRITE; + } else { + i2c->state = STATE_DONE; + oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_STOP); + goto out; + } + } + + if (i2c->state == STATE_READ) { + oc_setreg(i2c, OCI2C_CMD, i2c->pos == (msg->len-1) ? + OCI2C_CMD_READ_NACK : OCI2C_CMD_READ_ACK); + } else { + oc_setreg(i2c, OCI2C_DATA, msg->buf[i2c->pos++]); + oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_WRITE); + } + +out: + spin_unlock_irqrestore(&i2c->process_lock, flags); +} + +static irqreturn_t ocores_isr(int irq, void *dev_id) +{ + struct ocores_i2c *i2c = dev_id; + u8 stat = oc_getreg(i2c, OCI2C_STATUS); + + if (i2c->flags & OCORES_FLAG_BROKEN_IRQ) { + if ((stat & OCI2C_STAT_IF) && !(stat & OCI2C_STAT_BUSY)) + return IRQ_NONE; + } else if (!(stat & OCI2C_STAT_IF)) { + return IRQ_NONE; + } + ocores_process(i2c, stat); + + return IRQ_HANDLED; +} + +/** + * ocores_process_timeout() - Process timeout event + * @i2c: ocores I2C device instance + */ +static void ocores_process_timeout(struct ocores_i2c *i2c) +{ + unsigned long flags; + + spin_lock_irqsave(&i2c->process_lock, flags); + i2c->state = STATE_ERROR; + oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_STOP); + spin_unlock_irqrestore(&i2c->process_lock, flags); +} + +/** + * ocores_wait() - Wait until something change in a given register + * @i2c: ocores I2C device instance + * @reg: register to query + * @mask: bitmask to apply on register value + * @val: expected result + * @timeout: timeout in jiffies + * + * Timeout is necessary to avoid to stay here forever when the chip + * does not answer correctly. + * + * Return: 0 on success, -ETIMEDOUT on timeout + */ +static int ocores_wait(struct ocores_i2c *i2c, + int reg, u8 mask, u8 val, + const unsigned long timeout) +{ + unsigned long j; + + j = jiffies + timeout; + while (1) { + u8 status = oc_getreg(i2c, reg); + + if ((status & mask) == val) + break; + + if (time_after(jiffies, j)) + return -ETIMEDOUT; + } + return 0; +} + +/** + * ocores_poll_wait() - Wait until is possible to process some data + * @i2c: ocores I2C device instance + * + * Used when the device is in polling mode (interrupts disabled). + * + * Return: 0 on success, -ETIMEDOUT on timeout + */ +static int ocores_poll_wait(struct ocores_i2c *i2c) +{ + u8 mask; + int err; + + if (i2c->state == STATE_DONE || i2c->state == STATE_ERROR) { + /* transfer is over */ + mask = OCI2C_STAT_BUSY; + } else { + /* on going transfer */ + mask = OCI2C_STAT_TIP; + /* + * We wait for the data to be transferred (8bit), + * then we start polling on the ACK/NACK bit + */ + udelay((8 * 1000) / i2c->bus_clock_khz); + } + + /* + * once we are here we expect to get the expected result immediately + * so if after 1ms we timeout then something is broken. + */ + err = ocores_wait(i2c, OCI2C_STATUS, mask, 0, msecs_to_jiffies(1)); + if (err) + dev_warn(i2c->adap.dev.parent, + "%s: STATUS timeout, bit 0x%x did not clear in 1ms\n", + __func__, mask); + return err; +} + +/** + * ocores_process_polling() - It handles an IRQ-less transfer + * @i2c: ocores I2C device instance + * + * Even if IRQ are disabled, the I2C OpenCore IP behavior is exactly the same + * (only that IRQ are not produced). This means that we can re-use entirely + * ocores_isr(), we just add our polling code around it. + * + * It can run in atomic context + * + * Return: 0 on success, -ETIMEDOUT on timeout + */ +static int ocores_process_polling(struct ocores_i2c *i2c) +{ + irqreturn_t ret; + int err = 0; + + while (1) { + err = ocores_poll_wait(i2c); + if (err) + break; /* timeout */ + + ret = ocores_isr(-1, i2c); + if (ret == IRQ_NONE) + break; /* all messages have been transferred */ + else { + if (i2c->flags & OCORES_FLAG_BROKEN_IRQ) + if (i2c->state == STATE_DONE) + break; + } + } + + return err; +} + +static int ocores_xfer_core(struct ocores_i2c *i2c, + struct i2c_msg *msgs, int num, + bool polling) +{ + int ret = 0; + u8 ctrl; + + ctrl = oc_getreg(i2c, OCI2C_CONTROL); + if (polling) + oc_setreg(i2c, OCI2C_CONTROL, ctrl & ~OCI2C_CTRL_IEN); + else + oc_setreg(i2c, OCI2C_CONTROL, ctrl | OCI2C_CTRL_IEN); + + i2c->msg = msgs; + i2c->pos = 0; + i2c->nmsgs = num; + i2c->state = STATE_START; + + oc_setreg(i2c, OCI2C_DATA, i2c_8bit_addr_from_msg(i2c->msg)); + oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_START); + + if (polling) { + ret = ocores_process_polling(i2c); + } else { + if (wait_event_timeout(i2c->wait, + (i2c->state == STATE_ERROR) || + (i2c->state == STATE_DONE), HZ) == 0) + ret = -ETIMEDOUT; + } + if (ret) { + ocores_process_timeout(i2c); + return ret; + } + + return (i2c->state == STATE_DONE) ? num : -EIO; +} + +static int ocores_xfer_polling(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + return ocores_xfer_core(i2c_get_adapdata(adap), msgs, num, true); +} + +static int ocores_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + return ocores_xfer_core(i2c_get_adapdata(adap), msgs, num, false); +} + +static int ocores_init(struct device *dev, struct ocores_i2c *i2c) +{ + int prescale; + int diff; + u8 ctrl = oc_getreg(i2c, OCI2C_CONTROL); + + /* make sure the device is disabled */ + ctrl &= ~(OCI2C_CTRL_EN | OCI2C_CTRL_IEN); + oc_setreg(i2c, OCI2C_CONTROL, ctrl); + + prescale = (i2c->ip_clock_khz / (5 * i2c->bus_clock_khz)) - 1; + prescale = clamp(prescale, 0, 0xffff); + + diff = i2c->ip_clock_khz / (5 * (prescale + 1)) - i2c->bus_clock_khz; + if (abs(diff) > i2c->bus_clock_khz / 10) { + dev_err(dev, + "Unsupported clock settings: core: %d KHz, bus: %d KHz\n", + i2c->ip_clock_khz, i2c->bus_clock_khz); + return -EINVAL; + } + + oc_setreg(i2c, OCI2C_PRELOW, prescale & 0xff); + oc_setreg(i2c, OCI2C_PREHIGH, prescale >> 8); + + /* Init the device */ + oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_IACK); + oc_setreg(i2c, OCI2C_CONTROL, ctrl | OCI2C_CTRL_EN); + + return 0; +} + + +static u32 ocores_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static struct i2c_algorithm ocores_algorithm = { + .master_xfer = ocores_xfer, + .master_xfer_atomic = ocores_xfer_polling, + .functionality = ocores_func, +}; + +static const struct i2c_adapter ocores_adapter = { + .owner = THIS_MODULE, + .name = "i2c-ocores", + .class = I2C_CLASS_DEPRECATED, + .algo = &ocores_algorithm, +}; + +static const struct of_device_id ocores_i2c_match[] = { + { + .compatible = "opencores,i2c-ocores", + .data = (void *)TYPE_OCORES, + }, + { + .compatible = "aeroflexgaisler,i2cmst", + .data = (void *)TYPE_GRLIB, + }, + { + .compatible = "sifive,fu540-c000-i2c", + }, + { + .compatible = "sifive,i2c0", + }, + {}, +}; +MODULE_DEVICE_TABLE(of, ocores_i2c_match); + +#ifdef CONFIG_OF +/* + * Read and write functions for the GRLIB port of the controller. Registers are + * 32-bit big endian and the PRELOW and PREHIGH registers are merged into one + * register. The subsequent registers have their offsets decreased accordingly. + */ +static u8 oc_getreg_grlib(struct ocores_i2c *i2c, int reg) +{ + u32 rd; + int rreg = reg; + + if (reg != OCI2C_PRELOW) + rreg--; + rd = ioread32be(i2c->base + (rreg << i2c->reg_shift)); + if (reg == OCI2C_PREHIGH) + return (u8)(rd >> 8); + else + return (u8)rd; +} + +static void oc_setreg_grlib(struct ocores_i2c *i2c, int reg, u8 value) +{ + u32 curr, wr; + int rreg = reg; + + if (reg != OCI2C_PRELOW) + rreg--; + if (reg == OCI2C_PRELOW || reg == OCI2C_PREHIGH) { + curr = ioread32be(i2c->base + (rreg << i2c->reg_shift)); + if (reg == OCI2C_PRELOW) + wr = (curr & 0xff00) | value; + else + wr = (((u32)value) << 8) | (curr & 0xff); + } else { + wr = value; + } + iowrite32be(wr, i2c->base + (rreg << i2c->reg_shift)); +} + +static int ocores_i2c_of_probe(struct platform_device *pdev, + struct ocores_i2c *i2c) +{ + struct device_node *np = pdev->dev.of_node; + const struct of_device_id *match; + u32 val; + u32 clock_frequency; + bool clock_frequency_present; + + if (of_property_read_u32(np, "reg-shift", &i2c->reg_shift)) { + /* no 'reg-shift', check for deprecated 'regstep' */ + if (!of_property_read_u32(np, "regstep", &val)) { + if (!is_power_of_2(val)) { + dev_err(&pdev->dev, "invalid regstep %d\n", + val); + return -EINVAL; + } + i2c->reg_shift = ilog2(val); + dev_warn(&pdev->dev, + "regstep property deprecated, use reg-shift\n"); + } + } + + clock_frequency_present = !of_property_read_u32(np, "clock-frequency", + &clock_frequency); + i2c->bus_clock_khz = 100; + + i2c->clk = devm_clk_get_optional_enabled(&pdev->dev, NULL); + if (IS_ERR(i2c->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(i2c->clk), + "devm_clk_get_optional_enabled failed\n"); + + i2c->ip_clock_khz = clk_get_rate(i2c->clk) / 1000; + if (clock_frequency_present) + i2c->bus_clock_khz = clock_frequency / 1000; + if (i2c->ip_clock_khz == 0) { + if (of_property_read_u32(np, "opencores,ip-clock-frequency", + &val)) { + if (!clock_frequency_present) { + dev_err(&pdev->dev, + "Missing required parameter 'opencores,ip-clock-frequency'\n"); + return -ENODEV; + } + i2c->ip_clock_khz = clock_frequency / 1000; + dev_warn(&pdev->dev, + "Deprecated usage of the 'clock-frequency' property, please update to 'opencores,ip-clock-frequency'\n"); + } else { + i2c->ip_clock_khz = val / 1000; + if (clock_frequency_present) + i2c->bus_clock_khz = clock_frequency / 1000; + } + } + + of_property_read_u32(pdev->dev.of_node, "reg-io-width", + &i2c->reg_io_width); + + match = of_match_node(ocores_i2c_match, pdev->dev.of_node); + if (match && (long)match->data == TYPE_GRLIB) { + dev_dbg(&pdev->dev, "GRLIB variant of i2c-ocores\n"); + i2c->setreg = oc_setreg_grlib; + i2c->getreg = oc_getreg_grlib; + } + + return 0; +} +#else +#define ocores_i2c_of_probe(pdev, i2c) -ENODEV +#endif + +static int ocores_i2c_probe(struct platform_device *pdev) +{ + struct ocores_i2c *i2c; + struct ocores_i2c_platform_data *pdata; + struct resource *res; + int irq; + int ret; + int i; + + i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + spin_lock_init(&i2c->process_lock); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (res) { + i2c->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(i2c->base)) + return PTR_ERR(i2c->base); + } else { + res = platform_get_resource(pdev, IORESOURCE_IO, 0); + if (!res) + return -EINVAL; + i2c->iobase = res->start; + if (!devm_request_region(&pdev->dev, res->start, + resource_size(res), + pdev->name)) { + dev_err(&pdev->dev, "Can't get I/O resource.\n"); + return -EBUSY; + } + i2c->setreg = oc_setreg_io_8; + i2c->getreg = oc_getreg_io_8; + } + + pdata = dev_get_platdata(&pdev->dev); + if (pdata) { + i2c->reg_shift = pdata->reg_shift; + i2c->reg_io_width = pdata->reg_io_width; + i2c->ip_clock_khz = pdata->clock_khz; + if (pdata->bus_khz) + i2c->bus_clock_khz = pdata->bus_khz; + else + i2c->bus_clock_khz = 100; + } else { + ret = ocores_i2c_of_probe(pdev, i2c); + if (ret) + return ret; + } + + if (i2c->reg_io_width == 0) + i2c->reg_io_width = 1; /* Set to default value */ + + if (!i2c->setreg || !i2c->getreg) { + bool be = pdata ? pdata->big_endian : + of_device_is_big_endian(pdev->dev.of_node); + + switch (i2c->reg_io_width) { + case 1: + i2c->setreg = oc_setreg_8; + i2c->getreg = oc_getreg_8; + break; + + case 2: + i2c->setreg = be ? oc_setreg_16be : oc_setreg_16; + i2c->getreg = be ? oc_getreg_16be : oc_getreg_16; + break; + + case 4: + i2c->setreg = be ? oc_setreg_32be : oc_setreg_32; + i2c->getreg = be ? oc_getreg_32be : oc_getreg_32; + break; + + default: + dev_err(&pdev->dev, "Unsupported I/O width (%d)\n", + i2c->reg_io_width); + return -EINVAL; + } + } + + init_waitqueue_head(&i2c->wait); + + irq = platform_get_irq_optional(pdev, 0); + /* + * Since the SoC does have an interrupt, its DT has an interrupt + * property - But this should be bypassed as the IRQ logic in this + * SoC is broken. + */ + if (of_device_is_compatible(pdev->dev.of_node, + "sifive,fu540-c000-i2c")) { + i2c->flags |= OCORES_FLAG_BROKEN_IRQ; + irq = -ENXIO; + } + + if (irq == -ENXIO) { + ocores_algorithm.master_xfer = ocores_xfer_polling; + } else { + if (irq < 0) + return irq; + } + + if (ocores_algorithm.master_xfer != ocores_xfer_polling) { + ret = devm_request_any_context_irq(&pdev->dev, irq, + ocores_isr, 0, + pdev->name, i2c); + if (ret) { + dev_err(&pdev->dev, "Cannot claim IRQ\n"); + return ret; + } + } + + ret = ocores_init(&pdev->dev, i2c); + if (ret) + return ret; + + /* hook up driver to tree */ + platform_set_drvdata(pdev, i2c); + i2c->adap = ocores_adapter; + i2c_set_adapdata(&i2c->adap, i2c); + i2c->adap.dev.parent = &pdev->dev; + i2c->adap.dev.of_node = pdev->dev.of_node; + + /* add i2c adapter to i2c tree */ + ret = i2c_add_adapter(&i2c->adap); + if (ret) + return ret; + + /* add in known devices to the bus */ + if (pdata) { + for (i = 0; i < pdata->num_devices; i++) + i2c_new_client_device(&i2c->adap, pdata->devices + i); + } + + return 0; +} + +static void ocores_i2c_remove(struct platform_device *pdev) +{ + struct ocores_i2c *i2c = platform_get_drvdata(pdev); + u8 ctrl = oc_getreg(i2c, OCI2C_CONTROL); + + /* disable i2c logic */ + ctrl &= ~(OCI2C_CTRL_EN | OCI2C_CTRL_IEN); + oc_setreg(i2c, OCI2C_CONTROL, ctrl); + + /* remove adapter & data */ + i2c_del_adapter(&i2c->adap); +} + +static int ocores_i2c_suspend(struct device *dev) +{ + struct ocores_i2c *i2c = dev_get_drvdata(dev); + u8 ctrl = oc_getreg(i2c, OCI2C_CONTROL); + + /* make sure the device is disabled */ + ctrl &= ~(OCI2C_CTRL_EN | OCI2C_CTRL_IEN); + oc_setreg(i2c, OCI2C_CONTROL, ctrl); + + clk_disable_unprepare(i2c->clk); + return 0; +} + +static int ocores_i2c_resume(struct device *dev) +{ + struct ocores_i2c *i2c = dev_get_drvdata(dev); + unsigned long rate; + int ret; + + ret = clk_prepare_enable(i2c->clk); + if (ret) + return dev_err_probe(dev, ret, "clk_prepare_enable failed\n"); + rate = clk_get_rate(i2c->clk) / 1000; + if (rate) + i2c->ip_clock_khz = rate; + return ocores_init(dev, i2c); +} + +static DEFINE_NOIRQ_DEV_PM_OPS(ocores_i2c_pm, + ocores_i2c_suspend, ocores_i2c_resume); + +static struct platform_driver ocores_i2c_driver = { + .probe = ocores_i2c_probe, + .remove_new = ocores_i2c_remove, + .driver = { + .name = "ocores-i2c", + .of_match_table = ocores_i2c_match, + .pm = pm_sleep_ptr(&ocores_i2c_pm), + }, +}; + +module_platform_driver(ocores_i2c_driver); + +MODULE_AUTHOR("Peter Korsgaard <peter@korsgaard.com>"); +MODULE_DESCRIPTION("OpenCores I2C bus driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:ocores-i2c"); diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c new file mode 100644 index 000000000..845eda70b --- /dev/null +++ b/drivers/i2c/busses/i2c-octeon-core.c @@ -0,0 +1,792 @@ +/* + * (C) Copyright 2009-2010 + * Nokia Siemens Networks, michael.lawnick.ext@nsn.com + * + * Portions Copyright (C) 2010 - 2016 Cavium, Inc. + * + * This file contains the shared part of the driver for the i2c adapter in + * Cavium Networks' OCTEON processors and ThunderX SOCs. + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> + +#include "i2c-octeon-core.h" + +/* interrupt service routine */ +irqreturn_t octeon_i2c_isr(int irq, void *dev_id) +{ + struct octeon_i2c *i2c = dev_id; + + i2c->int_disable(i2c); + wake_up(&i2c->queue); + + return IRQ_HANDLED; +} + +static bool octeon_i2c_test_iflg(struct octeon_i2c *i2c) +{ + return (octeon_i2c_ctl_read(i2c) & TWSI_CTL_IFLG); +} + +/** + * octeon_i2c_wait - wait for the IFLG to be set + * @i2c: The struct octeon_i2c + * + * Returns 0 on success, otherwise a negative errno. + */ +static int octeon_i2c_wait(struct octeon_i2c *i2c) +{ + long time_left; + + /* + * Some chip revisions don't assert the irq in the interrupt + * controller. So we must poll for the IFLG change. + */ + if (i2c->broken_irq_mode) { + u64 end = get_jiffies_64() + i2c->adap.timeout; + + while (!octeon_i2c_test_iflg(i2c) && + time_before64(get_jiffies_64(), end)) + usleep_range(I2C_OCTEON_EVENT_WAIT / 2, I2C_OCTEON_EVENT_WAIT); + + return octeon_i2c_test_iflg(i2c) ? 0 : -ETIMEDOUT; + } + + i2c->int_enable(i2c); + time_left = wait_event_timeout(i2c->queue, octeon_i2c_test_iflg(i2c), + i2c->adap.timeout); + i2c->int_disable(i2c); + + if (i2c->broken_irq_check && !time_left && + octeon_i2c_test_iflg(i2c)) { + dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n"); + i2c->broken_irq_mode = true; + return 0; + } + + if (!time_left) + return -ETIMEDOUT; + + return 0; +} + +static bool octeon_i2c_hlc_test_valid(struct octeon_i2c *i2c) +{ + return (__raw_readq(i2c->twsi_base + SW_TWSI(i2c)) & SW_TWSI_V) == 0; +} + +static void octeon_i2c_hlc_int_clear(struct octeon_i2c *i2c) +{ + /* clear ST/TS events, listen for neither */ + octeon_i2c_write_int(i2c, TWSI_INT_ST_INT | TWSI_INT_TS_INT); +} + +/* + * Cleanup low-level state & enable high-level controller. + */ +static void octeon_i2c_hlc_enable(struct octeon_i2c *i2c) +{ + int try = 0; + u64 val; + + if (i2c->hlc_enabled) + return; + i2c->hlc_enabled = true; + + while (1) { + val = octeon_i2c_ctl_read(i2c); + if (!(val & (TWSI_CTL_STA | TWSI_CTL_STP))) + break; + + /* clear IFLG event */ + if (val & TWSI_CTL_IFLG) + octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB); + + if (try++ > 100) { + pr_err("%s: giving up\n", __func__); + break; + } + + /* spin until any start/stop has finished */ + udelay(10); + } + octeon_i2c_ctl_write(i2c, TWSI_CTL_CE | TWSI_CTL_AAK | TWSI_CTL_ENAB); +} + +static void octeon_i2c_hlc_disable(struct octeon_i2c *i2c) +{ + if (!i2c->hlc_enabled) + return; + + i2c->hlc_enabled = false; + octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB); +} + +/** + * octeon_i2c_hlc_wait - wait for an HLC operation to complete + * @i2c: The struct octeon_i2c + * + * Returns 0 on success, otherwise -ETIMEDOUT. + */ +static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c) +{ + int time_left; + + /* + * Some cn38xx boards don't assert the irq in the interrupt + * controller. So we must poll for the valid bit change. + */ + if (i2c->broken_irq_mode) { + u64 end = get_jiffies_64() + i2c->adap.timeout; + + while (!octeon_i2c_hlc_test_valid(i2c) && + time_before64(get_jiffies_64(), end)) + usleep_range(I2C_OCTEON_EVENT_WAIT / 2, I2C_OCTEON_EVENT_WAIT); + + return octeon_i2c_hlc_test_valid(i2c) ? 0 : -ETIMEDOUT; + } + + i2c->hlc_int_enable(i2c); + time_left = wait_event_timeout(i2c->queue, + octeon_i2c_hlc_test_valid(i2c), + i2c->adap.timeout); + i2c->hlc_int_disable(i2c); + if (!time_left) + octeon_i2c_hlc_int_clear(i2c); + + if (i2c->broken_irq_check && !time_left && + octeon_i2c_hlc_test_valid(i2c)) { + dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n"); + i2c->broken_irq_mode = true; + return 0; + } + + if (!time_left) + return -ETIMEDOUT; + return 0; +} + +static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read) +{ + u8 stat; + + /* + * This is ugly... in HLC mode the status is not in the status register + * but in the lower 8 bits of SW_TWSI. + */ + if (i2c->hlc_enabled) + stat = __raw_readq(i2c->twsi_base + SW_TWSI(i2c)); + else + stat = octeon_i2c_stat_read(i2c); + + switch (stat) { + /* Everything is fine */ + case STAT_IDLE: + case STAT_AD2W_ACK: + case STAT_RXADDR_ACK: + case STAT_TXADDR_ACK: + case STAT_TXDATA_ACK: + return 0; + + /* ACK allowed on pre-terminal bytes only */ + case STAT_RXDATA_ACK: + if (!final_read) + return 0; + return -EIO; + + /* NAK allowed on terminal byte only */ + case STAT_RXDATA_NAK: + if (final_read) + return 0; + return -EIO; + + /* Arbitration lost */ + case STAT_LOST_ARB_38: + case STAT_LOST_ARB_68: + case STAT_LOST_ARB_78: + case STAT_LOST_ARB_B0: + return -EAGAIN; + + /* Being addressed as slave, should back off & listen */ + case STAT_SLAVE_60: + case STAT_SLAVE_70: + case STAT_GENDATA_ACK: + case STAT_GENDATA_NAK: + return -EOPNOTSUPP; + + /* Core busy as slave */ + case STAT_SLAVE_80: + case STAT_SLAVE_88: + case STAT_SLAVE_A0: + case STAT_SLAVE_A8: + case STAT_SLAVE_LOST: + case STAT_SLAVE_NAK: + case STAT_SLAVE_ACK: + return -EOPNOTSUPP; + + case STAT_TXDATA_NAK: + case STAT_BUS_ERROR: + return -EIO; + case STAT_TXADDR_NAK: + case STAT_RXADDR_NAK: + case STAT_AD2W_NAK: + return -ENXIO; + default: + dev_err(i2c->dev, "unhandled state: %d\n", stat); + return -EIO; + } +} + +static int octeon_i2c_recovery(struct octeon_i2c *i2c) +{ + int ret; + + ret = i2c_recover_bus(&i2c->adap); + if (ret) + /* recover failed, try hardware re-init */ + ret = octeon_i2c_init_lowlevel(i2c); + return ret; +} + +/** + * octeon_i2c_start - send START to the bus + * @i2c: The struct octeon_i2c + * + * Returns 0 on success, otherwise a negative errno. + */ +static int octeon_i2c_start(struct octeon_i2c *i2c) +{ + int ret; + u8 stat; + + octeon_i2c_hlc_disable(i2c); + + octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_STA); + ret = octeon_i2c_wait(i2c); + if (ret) + goto error; + + stat = octeon_i2c_stat_read(i2c); + if (stat == STAT_START || stat == STAT_REP_START) + /* START successful, bail out */ + return 0; + +error: + /* START failed, try to recover */ + ret = octeon_i2c_recovery(i2c); + return (ret) ? ret : -EAGAIN; +} + +/* send STOP to the bus */ +static void octeon_i2c_stop(struct octeon_i2c *i2c) +{ + octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_STP); +} + +/** + * octeon_i2c_read - receive data from the bus via low-level controller + * @i2c: The struct octeon_i2c + * @target: Target address + * @data: Pointer to the location to store the data + * @rlength: Length of the data + * @recv_len: flag for length byte + * + * The address is sent over the bus, then the data is read. + * + * Returns 0 on success, otherwise a negative errno. + */ +static int octeon_i2c_read(struct octeon_i2c *i2c, int target, + u8 *data, u16 *rlength, bool recv_len) +{ + int i, result, length = *rlength; + bool final_read = false; + + octeon_i2c_data_write(i2c, (target << 1) | 1); + octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB); + + result = octeon_i2c_wait(i2c); + if (result) + return result; + + /* address OK ? */ + result = octeon_i2c_check_status(i2c, false); + if (result) + return result; + + for (i = 0; i < length; i++) { + /* + * For the last byte to receive TWSI_CTL_AAK must not be set. + * + * A special case is I2C_M_RECV_LEN where we don't know the + * additional length yet. If recv_len is set we assume we're + * not reading the final byte and therefore need to set + * TWSI_CTL_AAK. + */ + if ((i + 1 == length) && !(recv_len && i == 0)) + final_read = true; + + /* clear iflg to allow next event */ + if (final_read) + octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB); + else + octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_AAK); + + result = octeon_i2c_wait(i2c); + if (result) + return result; + + data[i] = octeon_i2c_data_read(i2c, &result); + if (result) + return result; + if (recv_len && i == 0) { + if (data[i] > I2C_SMBUS_BLOCK_MAX) + return -EPROTO; + length += data[i]; + } + + result = octeon_i2c_check_status(i2c, final_read); + if (result) + return result; + } + *rlength = length; + return 0; +} + +/** + * octeon_i2c_write - send data to the bus via low-level controller + * @i2c: The struct octeon_i2c + * @target: Target address + * @data: Pointer to the data to be sent + * @length: Length of the data + * + * The address is sent over the bus, then the data. + * + * Returns 0 on success, otherwise a negative errno. + */ +static int octeon_i2c_write(struct octeon_i2c *i2c, int target, + const u8 *data, int length) +{ + int i, result; + + octeon_i2c_data_write(i2c, target << 1); + octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB); + + result = octeon_i2c_wait(i2c); + if (result) + return result; + + for (i = 0; i < length; i++) { + result = octeon_i2c_check_status(i2c, false); + if (result) + return result; + + octeon_i2c_data_write(i2c, data[i]); + octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB); + + result = octeon_i2c_wait(i2c); + if (result) + return result; + } + + return 0; +} + +/* high-level-controller pure read of up to 8 bytes */ +static int octeon_i2c_hlc_read(struct octeon_i2c *i2c, struct i2c_msg *msgs) +{ + int i, j, ret = 0; + u64 cmd; + + octeon_i2c_hlc_enable(i2c); + octeon_i2c_hlc_int_clear(i2c); + + cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR; + /* SIZE */ + cmd |= (u64)(msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT; + /* A */ + cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT; + + if (msgs[0].flags & I2C_M_TEN) + cmd |= SW_TWSI_OP_10; + else + cmd |= SW_TWSI_OP_7; + + octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI(i2c)); + ret = octeon_i2c_hlc_wait(i2c); + if (ret) + goto err; + + cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c)); + if ((cmd & SW_TWSI_R) == 0) + return octeon_i2c_check_status(i2c, false); + + for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--) + msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff; + + if (msgs[0].len > 4) { + cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT(i2c)); + for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--) + msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff; + } + +err: + return ret; +} + +/* high-level-controller pure write of up to 8 bytes */ +static int octeon_i2c_hlc_write(struct octeon_i2c *i2c, struct i2c_msg *msgs) +{ + int i, j, ret = 0; + u64 cmd; + + octeon_i2c_hlc_enable(i2c); + octeon_i2c_hlc_int_clear(i2c); + + cmd = SW_TWSI_V | SW_TWSI_SOVR; + /* SIZE */ + cmd |= (u64)(msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT; + /* A */ + cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT; + + if (msgs[0].flags & I2C_M_TEN) + cmd |= SW_TWSI_OP_10; + else + cmd |= SW_TWSI_OP_7; + + for (i = 0, j = msgs[0].len - 1; i < msgs[0].len && i < 4; i++, j--) + cmd |= (u64)msgs[0].buf[j] << (8 * i); + + if (msgs[0].len > 4) { + u64 ext = 0; + + for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--) + ext |= (u64)msgs[0].buf[j] << (8 * i); + octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT(i2c)); + } + + octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI(i2c)); + ret = octeon_i2c_hlc_wait(i2c); + if (ret) + goto err; + + cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c)); + if ((cmd & SW_TWSI_R) == 0) + return octeon_i2c_check_status(i2c, false); + +err: + return ret; +} + +/* high-level-controller composite write+read, msg0=addr, msg1=data */ +static int octeon_i2c_hlc_comp_read(struct octeon_i2c *i2c, struct i2c_msg *msgs) +{ + int i, j, ret = 0; + u64 cmd; + + octeon_i2c_hlc_enable(i2c); + + cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR; + /* SIZE */ + cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT; + /* A */ + cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT; + + if (msgs[0].flags & I2C_M_TEN) + cmd |= SW_TWSI_OP_10_IA; + else + cmd |= SW_TWSI_OP_7_IA; + + if (msgs[0].len == 2) { + u64 ext = 0; + + cmd |= SW_TWSI_EIA; + ext = (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT; + cmd |= (u64)msgs[0].buf[1] << SW_TWSI_IA_SHIFT; + octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT(i2c)); + } else { + cmd |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT; + } + + octeon_i2c_hlc_int_clear(i2c); + octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI(i2c)); + + ret = octeon_i2c_hlc_wait(i2c); + if (ret) + goto err; + + cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c)); + if ((cmd & SW_TWSI_R) == 0) + return octeon_i2c_check_status(i2c, false); + + for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--) + msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff; + + if (msgs[1].len > 4) { + cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT(i2c)); + for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--) + msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff; + } + +err: + return ret; +} + +/* high-level-controller composite write+write, m[0]len<=2, m[1]len<=8 */ +static int octeon_i2c_hlc_comp_write(struct octeon_i2c *i2c, struct i2c_msg *msgs) +{ + bool set_ext = false; + int i, j, ret = 0; + u64 cmd, ext = 0; + + octeon_i2c_hlc_enable(i2c); + + cmd = SW_TWSI_V | SW_TWSI_SOVR; + /* SIZE */ + cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT; + /* A */ + cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT; + + if (msgs[0].flags & I2C_M_TEN) + cmd |= SW_TWSI_OP_10_IA; + else + cmd |= SW_TWSI_OP_7_IA; + + if (msgs[0].len == 2) { + cmd |= SW_TWSI_EIA; + ext |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT; + set_ext = true; + cmd |= (u64)msgs[0].buf[1] << SW_TWSI_IA_SHIFT; + } else { + cmd |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT; + } + + for (i = 0, j = msgs[1].len - 1; i < msgs[1].len && i < 4; i++, j--) + cmd |= (u64)msgs[1].buf[j] << (8 * i); + + if (msgs[1].len > 4) { + for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--) + ext |= (u64)msgs[1].buf[j] << (8 * i); + set_ext = true; + } + if (set_ext) + octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT(i2c)); + + octeon_i2c_hlc_int_clear(i2c); + octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI(i2c)); + + ret = octeon_i2c_hlc_wait(i2c); + if (ret) + goto err; + + cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c)); + if ((cmd & SW_TWSI_R) == 0) + return octeon_i2c_check_status(i2c, false); + +err: + return ret; +} + +/** + * octeon_i2c_xfer - The driver's master_xfer function + * @adap: Pointer to the i2c_adapter structure + * @msgs: Pointer to the messages to be processed + * @num: Length of the MSGS array + * + * Returns the number of messages processed, or a negative errno on failure. + */ +int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + struct octeon_i2c *i2c = i2c_get_adapdata(adap); + int i, ret = 0; + + if (num == 1) { + if (msgs[0].len > 0 && msgs[0].len <= 8) { + if (msgs[0].flags & I2C_M_RD) + ret = octeon_i2c_hlc_read(i2c, msgs); + else + ret = octeon_i2c_hlc_write(i2c, msgs); + goto out; + } + } else if (num == 2) { + if ((msgs[0].flags & I2C_M_RD) == 0 && + (msgs[1].flags & I2C_M_RECV_LEN) == 0 && + msgs[0].len > 0 && msgs[0].len <= 2 && + msgs[1].len > 0 && msgs[1].len <= 8 && + msgs[0].addr == msgs[1].addr) { + if (msgs[1].flags & I2C_M_RD) + ret = octeon_i2c_hlc_comp_read(i2c, msgs); + else + ret = octeon_i2c_hlc_comp_write(i2c, msgs); + goto out; + } + } + + for (i = 0; ret == 0 && i < num; i++) { + struct i2c_msg *pmsg = &msgs[i]; + + /* zero-length messages are not supported */ + if (!pmsg->len) { + ret = -EOPNOTSUPP; + break; + } + + ret = octeon_i2c_start(i2c); + if (ret) + return ret; + + if (pmsg->flags & I2C_M_RD) + ret = octeon_i2c_read(i2c, pmsg->addr, pmsg->buf, + &pmsg->len, pmsg->flags & I2C_M_RECV_LEN); + else + ret = octeon_i2c_write(i2c, pmsg->addr, pmsg->buf, + pmsg->len); + } + octeon_i2c_stop(i2c); +out: + return (ret != 0) ? ret : num; +} + +/* calculate and set clock divisors */ +void octeon_i2c_set_clock(struct octeon_i2c *i2c) +{ + int tclk, thp_base, inc, thp_idx, mdiv_idx, ndiv_idx, foscl, diff; + int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = 1000000; + + for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) { + /* + * An mdiv value of less than 2 seems to not work well + * with ds1337 RTCs, so we constrain it to larger values. + */ + for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) { + /* + * For given ndiv and mdiv values check the + * two closest thp values. + */ + tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10; + tclk *= (1 << ndiv_idx); + thp_base = (i2c->sys_freq / (tclk * 2)) - 1; + + for (inc = 0; inc <= 1; inc++) { + thp_idx = thp_base + inc; + if (thp_idx < 5 || thp_idx > 0xff) + continue; + + foscl = i2c->sys_freq / (2 * (thp_idx + 1)); + foscl = foscl / (1 << ndiv_idx); + foscl = foscl / (mdiv_idx + 1) / 10; + diff = abs(foscl - i2c->twsi_freq); + if (diff < delta_hz) { + delta_hz = diff; + thp = thp_idx; + mdiv = mdiv_idx; + ndiv = ndiv_idx; + } + } + } + } + octeon_i2c_reg_write(i2c, SW_TWSI_OP_TWSI_CLK, thp); + octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv); +} + +int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c) +{ + u8 status = 0; + int tries; + + /* reset controller */ + octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_RST, 0); + + for (tries = 10; tries && status != STAT_IDLE; tries--) { + udelay(1); + status = octeon_i2c_stat_read(i2c); + if (status == STAT_IDLE) + break; + } + + if (status != STAT_IDLE) { + dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n", + __func__, status); + return -EIO; + } + + /* toggle twice to force both teardowns */ + octeon_i2c_hlc_enable(i2c); + octeon_i2c_hlc_disable(i2c); + return 0; +} + +static int octeon_i2c_get_scl(struct i2c_adapter *adap) +{ + struct octeon_i2c *i2c = i2c_get_adapdata(adap); + u64 state; + + state = octeon_i2c_read_int(i2c); + return state & TWSI_INT_SCL; +} + +static void octeon_i2c_set_scl(struct i2c_adapter *adap, int val) +{ + struct octeon_i2c *i2c = i2c_get_adapdata(adap); + + octeon_i2c_write_int(i2c, val ? 0 : TWSI_INT_SCL_OVR); +} + +static int octeon_i2c_get_sda(struct i2c_adapter *adap) +{ + struct octeon_i2c *i2c = i2c_get_adapdata(adap); + u64 state; + + state = octeon_i2c_read_int(i2c); + return state & TWSI_INT_SDA; +} + +static void octeon_i2c_prepare_recovery(struct i2c_adapter *adap) +{ + struct octeon_i2c *i2c = i2c_get_adapdata(adap); + + octeon_i2c_hlc_disable(i2c); + octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_RST, 0); + /* wait for software reset to settle */ + udelay(5); + + /* + * Bring control register to a good state regardless + * of HLC state. + */ + octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB); + + octeon_i2c_write_int(i2c, 0); +} + +static void octeon_i2c_unprepare_recovery(struct i2c_adapter *adap) +{ + struct octeon_i2c *i2c = i2c_get_adapdata(adap); + + /* + * Generate STOP to finish the unfinished transaction. + * Can't generate STOP via the TWSI CTL register + * since it could bring the TWSI controller into an inoperable state. + */ + octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR | TWSI_INT_SCL_OVR); + udelay(5); + octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR); + udelay(5); + octeon_i2c_write_int(i2c, 0); +} + +struct i2c_bus_recovery_info octeon_i2c_recovery_info = { + .recover_bus = i2c_generic_scl_recovery, + .get_scl = octeon_i2c_get_scl, + .set_scl = octeon_i2c_set_scl, + .get_sda = octeon_i2c_get_sda, + .prepare_recovery = octeon_i2c_prepare_recovery, + .unprepare_recovery = octeon_i2c_unprepare_recovery, +}; diff --git a/drivers/i2c/busses/i2c-octeon-core.h b/drivers/i2c/busses/i2c-octeon-core.h new file mode 100644 index 000000000..9bb9f64fd --- /dev/null +++ b/drivers/i2c/busses/i2c-octeon-core.h @@ -0,0 +1,219 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include <linux/atomic.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/i2c.h> +#include <linux/i2c-smbus.h> +#include <linux/io.h> +#include <linux/kernel.h> + +/* Controller command patterns */ +#define SW_TWSI_V BIT_ULL(63) /* Valid bit */ +#define SW_TWSI_EIA BIT_ULL(61) /* Extended internal address */ +#define SW_TWSI_R BIT_ULL(56) /* Result or read bit */ +#define SW_TWSI_SOVR BIT_ULL(55) /* Size override */ +#define SW_TWSI_SIZE_SHIFT 52 +#define SW_TWSI_ADDR_SHIFT 40 +#define SW_TWSI_IA_SHIFT 32 /* Internal address */ + +/* Controller opcode word (bits 60:57) */ +#define SW_TWSI_OP_SHIFT 57 +#define SW_TWSI_OP_7 (0ULL << SW_TWSI_OP_SHIFT) +#define SW_TWSI_OP_7_IA (1ULL << SW_TWSI_OP_SHIFT) +#define SW_TWSI_OP_10 (2ULL << SW_TWSI_OP_SHIFT) +#define SW_TWSI_OP_10_IA (3ULL << SW_TWSI_OP_SHIFT) +#define SW_TWSI_OP_TWSI_CLK (4ULL << SW_TWSI_OP_SHIFT) +#define SW_TWSI_OP_EOP (6ULL << SW_TWSI_OP_SHIFT) /* Extended opcode */ + +/* Controller extended opcode word (bits 34:32) */ +#define SW_TWSI_EOP_SHIFT 32 +#define SW_TWSI_EOP_TWSI_DATA (SW_TWSI_OP_EOP | 1ULL << SW_TWSI_EOP_SHIFT) +#define SW_TWSI_EOP_TWSI_CTL (SW_TWSI_OP_EOP | 2ULL << SW_TWSI_EOP_SHIFT) +#define SW_TWSI_EOP_TWSI_CLKCTL (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT) +#define SW_TWSI_EOP_TWSI_STAT (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT) +#define SW_TWSI_EOP_TWSI_RST (SW_TWSI_OP_EOP | 7ULL << SW_TWSI_EOP_SHIFT) + +/* Controller command and status bits */ +#define TWSI_CTL_CE 0x80 /* High level controller enable */ +#define TWSI_CTL_ENAB 0x40 /* Bus enable */ +#define TWSI_CTL_STA 0x20 /* Master-mode start, HW clears when done */ +#define TWSI_CTL_STP 0x10 /* Master-mode stop, HW clears when done */ +#define TWSI_CTL_IFLG 0x08 /* HW event, SW writes 0 to ACK */ +#define TWSI_CTL_AAK 0x04 /* Assert ACK */ + +/* Status values */ +#define STAT_BUS_ERROR 0x00 +#define STAT_START 0x08 +#define STAT_REP_START 0x10 +#define STAT_TXADDR_ACK 0x18 +#define STAT_TXADDR_NAK 0x20 +#define STAT_TXDATA_ACK 0x28 +#define STAT_TXDATA_NAK 0x30 +#define STAT_LOST_ARB_38 0x38 +#define STAT_RXADDR_ACK 0x40 +#define STAT_RXADDR_NAK 0x48 +#define STAT_RXDATA_ACK 0x50 +#define STAT_RXDATA_NAK 0x58 +#define STAT_SLAVE_60 0x60 +#define STAT_LOST_ARB_68 0x68 +#define STAT_SLAVE_70 0x70 +#define STAT_LOST_ARB_78 0x78 +#define STAT_SLAVE_80 0x80 +#define STAT_SLAVE_88 0x88 +#define STAT_GENDATA_ACK 0x90 +#define STAT_GENDATA_NAK 0x98 +#define STAT_SLAVE_A0 0xA0 +#define STAT_SLAVE_A8 0xA8 +#define STAT_LOST_ARB_B0 0xB0 +#define STAT_SLAVE_LOST 0xB8 +#define STAT_SLAVE_NAK 0xC0 +#define STAT_SLAVE_ACK 0xC8 +#define STAT_AD2W_ACK 0xD0 +#define STAT_AD2W_NAK 0xD8 +#define STAT_IDLE 0xF8 + +/* TWSI_INT values */ +#define TWSI_INT_ST_INT BIT_ULL(0) +#define TWSI_INT_TS_INT BIT_ULL(1) +#define TWSI_INT_CORE_INT BIT_ULL(2) +#define TWSI_INT_ST_EN BIT_ULL(4) +#define TWSI_INT_TS_EN BIT_ULL(5) +#define TWSI_INT_CORE_EN BIT_ULL(6) +#define TWSI_INT_SDA_OVR BIT_ULL(8) +#define TWSI_INT_SCL_OVR BIT_ULL(9) +#define TWSI_INT_SDA BIT_ULL(10) +#define TWSI_INT_SCL BIT_ULL(11) + +#define I2C_OCTEON_EVENT_WAIT 80 /* microseconds */ + +/* Register offsets */ +struct octeon_i2c_reg_offset { + unsigned int sw_twsi; + unsigned int twsi_int; + unsigned int sw_twsi_ext; +}; + +#define SW_TWSI(x) (x->roff.sw_twsi) +#define TWSI_INT(x) (x->roff.twsi_int) +#define SW_TWSI_EXT(x) (x->roff.sw_twsi_ext) + +struct octeon_i2c { + wait_queue_head_t queue; + struct i2c_adapter adap; + struct octeon_i2c_reg_offset roff; + struct clk *clk; + int irq; + int hlc_irq; /* For cn7890 only */ + u32 twsi_freq; + int sys_freq; + void __iomem *twsi_base; + struct device *dev; + bool hlc_enabled; + bool broken_irq_mode; + bool broken_irq_check; + void (*int_enable)(struct octeon_i2c *); + void (*int_disable)(struct octeon_i2c *); + void (*hlc_int_enable)(struct octeon_i2c *); + void (*hlc_int_disable)(struct octeon_i2c *); + atomic_t int_enable_cnt; + atomic_t hlc_int_enable_cnt; + struct i2c_smbus_alert_setup alert_data; + struct i2c_client *ara; +}; + +static inline void octeon_i2c_writeq_flush(u64 val, void __iomem *addr) +{ + __raw_writeq(val, addr); + __raw_readq(addr); /* wait for write to land */ +} + +/** + * octeon_i2c_reg_write - write an I2C core register + * @i2c: The struct octeon_i2c + * @eop_reg: Register selector + * @data: Value to be written + * + * The I2C core registers are accessed indirectly via the SW_TWSI CSR. + */ +static inline void octeon_i2c_reg_write(struct octeon_i2c *i2c, u64 eop_reg, u8 data) +{ + int tries = 1000; + u64 tmp; + + __raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + SW_TWSI(i2c)); + do { + tmp = __raw_readq(i2c->twsi_base + SW_TWSI(i2c)); + if (--tries < 0) + return; + } while ((tmp & SW_TWSI_V) != 0); +} + +#define octeon_i2c_ctl_write(i2c, val) \ + octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_CTL, val) +#define octeon_i2c_data_write(i2c, val) \ + octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_DATA, val) + +/** + * octeon_i2c_reg_read - read lower bits of an I2C core register + * @i2c: The struct octeon_i2c + * @eop_reg: Register selector + * + * Returns the data. + * + * The I2C core registers are accessed indirectly via the SW_TWSI CSR. + */ +static inline int octeon_i2c_reg_read(struct octeon_i2c *i2c, u64 eop_reg, + int *error) +{ + int tries = 1000; + u64 tmp; + + __raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base + SW_TWSI(i2c)); + do { + tmp = __raw_readq(i2c->twsi_base + SW_TWSI(i2c)); + if (--tries < 0) { + /* signal that the returned data is invalid */ + if (error) + *error = -EIO; + return 0; + } + } while ((tmp & SW_TWSI_V) != 0); + + return tmp & 0xFF; +} + +#define octeon_i2c_ctl_read(i2c) \ + octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_CTL, NULL) +#define octeon_i2c_data_read(i2c, error) \ + octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_DATA, error) +#define octeon_i2c_stat_read(i2c) \ + octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_STAT, NULL) + +/** + * octeon_i2c_read_int - read the TWSI_INT register + * @i2c: The struct octeon_i2c + * + * Returns the value of the register. + */ +static inline u64 octeon_i2c_read_int(struct octeon_i2c *i2c) +{ + return __raw_readq(i2c->twsi_base + TWSI_INT(i2c)); +} + +/** + * octeon_i2c_write_int - write the TWSI_INT register + * @i2c: The struct octeon_i2c + * @data: Value to be written + */ +static inline void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data) +{ + octeon_i2c_writeq_flush(data, i2c->twsi_base + TWSI_INT(i2c)); +} + +/* Prototypes */ +irqreturn_t octeon_i2c_isr(int irq, void *dev_id); +int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num); +int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c); +void octeon_i2c_set_clock(struct octeon_i2c *i2c); +extern struct i2c_bus_recovery_info octeon_i2c_recovery_info; diff --git a/drivers/i2c/busses/i2c-octeon-platdrv.c b/drivers/i2c/busses/i2c-octeon-platdrv.c new file mode 100644 index 000000000..7d54b3203 --- /dev/null +++ b/drivers/i2c/busses/i2c-octeon-platdrv.c @@ -0,0 +1,283 @@ +/* + * (C) Copyright 2009-2010 + * Nokia Siemens Networks, michael.lawnick.ext@nsn.com + * + * Portions Copyright (C) 2010 - 2016 Cavium, Inc. + * + * This is a driver for the i2c adapter in Cavium Networks' OCTEON processors. + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/atomic.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/slab.h> + +#include <asm/octeon/octeon.h> +#include "i2c-octeon-core.h" + +#define DRV_NAME "i2c-octeon" + +/** + * octeon_i2c_int_enable - enable the CORE interrupt + * @i2c: The struct octeon_i2c + * + * The interrupt will be asserted when there is non-STAT_IDLE state in + * the SW_TWSI_EOP_TWSI_STAT register. + */ +static void octeon_i2c_int_enable(struct octeon_i2c *i2c) +{ + octeon_i2c_write_int(i2c, TWSI_INT_CORE_EN); +} + +/* disable the CORE interrupt */ +static void octeon_i2c_int_disable(struct octeon_i2c *i2c) +{ + /* clear TS/ST/IFLG events */ + octeon_i2c_write_int(i2c, 0); +} + +/** + * octeon_i2c_int_enable78 - enable the CORE interrupt + * @i2c: The struct octeon_i2c + * + * The interrupt will be asserted when there is non-STAT_IDLE state in the + * SW_TWSI_EOP_TWSI_STAT register. + */ +static void octeon_i2c_int_enable78(struct octeon_i2c *i2c) +{ + atomic_inc_return(&i2c->int_enable_cnt); + enable_irq(i2c->irq); +} + +static void __octeon_i2c_irq_disable(atomic_t *cnt, int irq) +{ + int count; + + /* + * The interrupt can be disabled in two places, but we only + * want to make the disable_irq_nosync() call once, so keep + * track with the atomic variable. + */ + count = atomic_dec_if_positive(cnt); + if (count >= 0) + disable_irq_nosync(irq); +} + +/* disable the CORE interrupt */ +static void octeon_i2c_int_disable78(struct octeon_i2c *i2c) +{ + __octeon_i2c_irq_disable(&i2c->int_enable_cnt, i2c->irq); +} + +/** + * octeon_i2c_hlc_int_enable78 - enable the ST interrupt + * @i2c: The struct octeon_i2c + * + * The interrupt will be asserted when there is non-STAT_IDLE state in + * the SW_TWSI_EOP_TWSI_STAT register. + */ +static void octeon_i2c_hlc_int_enable78(struct octeon_i2c *i2c) +{ + atomic_inc_return(&i2c->hlc_int_enable_cnt); + enable_irq(i2c->hlc_irq); +} + +/* disable the ST interrupt */ +static void octeon_i2c_hlc_int_disable78(struct octeon_i2c *i2c) +{ + __octeon_i2c_irq_disable(&i2c->hlc_int_enable_cnt, i2c->hlc_irq); +} + +/* HLC interrupt service routine */ +static irqreturn_t octeon_i2c_hlc_isr78(int irq, void *dev_id) +{ + struct octeon_i2c *i2c = dev_id; + + i2c->hlc_int_disable(i2c); + wake_up(&i2c->queue); + + return IRQ_HANDLED; +} + +static void octeon_i2c_hlc_int_enable(struct octeon_i2c *i2c) +{ + octeon_i2c_write_int(i2c, TWSI_INT_ST_EN); +} + +static u32 octeon_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | + I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_SMBUS_BLOCK_PROC_CALL; +} + +static const struct i2c_algorithm octeon_i2c_algo = { + .master_xfer = octeon_i2c_xfer, + .functionality = octeon_i2c_functionality, +}; + +static const struct i2c_adapter octeon_i2c_ops = { + .owner = THIS_MODULE, + .name = "OCTEON adapter", + .algo = &octeon_i2c_algo, +}; + +static int octeon_i2c_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + int irq, result = 0, hlc_irq = 0; + struct octeon_i2c *i2c; + bool cn78xx_style; + + cn78xx_style = of_device_is_compatible(node, "cavium,octeon-7890-twsi"); + if (cn78xx_style) { + hlc_irq = platform_get_irq(pdev, 0); + if (hlc_irq < 0) + return hlc_irq; + + irq = platform_get_irq(pdev, 2); + if (irq < 0) + return irq; + } else { + /* All adaptors have an irq. */ + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + } + + i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) { + result = -ENOMEM; + goto out; + } + i2c->dev = &pdev->dev; + + i2c->roff.sw_twsi = 0x00; + i2c->roff.twsi_int = 0x10; + i2c->roff.sw_twsi_ext = 0x18; + + i2c->twsi_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c->twsi_base)) { + result = PTR_ERR(i2c->twsi_base); + goto out; + } + + /* + * "clock-rate" is a legacy binding, the official binding is + * "clock-frequency". Try the official one first and then + * fall back if it doesn't exist. + */ + if (of_property_read_u32(node, "clock-frequency", &i2c->twsi_freq) && + of_property_read_u32(node, "clock-rate", &i2c->twsi_freq)) { + dev_err(i2c->dev, + "no I2C 'clock-rate' or 'clock-frequency' property\n"); + result = -ENXIO; + goto out; + } + + i2c->sys_freq = octeon_get_io_clock_rate(); + + init_waitqueue_head(&i2c->queue); + + i2c->irq = irq; + + if (cn78xx_style) { + i2c->hlc_irq = hlc_irq; + + i2c->int_enable = octeon_i2c_int_enable78; + i2c->int_disable = octeon_i2c_int_disable78; + i2c->hlc_int_enable = octeon_i2c_hlc_int_enable78; + i2c->hlc_int_disable = octeon_i2c_hlc_int_disable78; + + irq_set_status_flags(i2c->irq, IRQ_NOAUTOEN); + irq_set_status_flags(i2c->hlc_irq, IRQ_NOAUTOEN); + + result = devm_request_irq(&pdev->dev, i2c->hlc_irq, + octeon_i2c_hlc_isr78, 0, + DRV_NAME, i2c); + if (result < 0) { + dev_err(i2c->dev, "failed to attach interrupt\n"); + goto out; + } + } else { + i2c->int_enable = octeon_i2c_int_enable; + i2c->int_disable = octeon_i2c_int_disable; + i2c->hlc_int_enable = octeon_i2c_hlc_int_enable; + i2c->hlc_int_disable = octeon_i2c_int_disable; + } + + result = devm_request_irq(&pdev->dev, i2c->irq, + octeon_i2c_isr, 0, DRV_NAME, i2c); + if (result < 0) { + dev_err(i2c->dev, "failed to attach interrupt\n"); + goto out; + } + + if (OCTEON_IS_MODEL(OCTEON_CN38XX)) + i2c->broken_irq_check = true; + + result = octeon_i2c_init_lowlevel(i2c); + if (result) { + dev_err(i2c->dev, "init low level failed\n"); + goto out; + } + + octeon_i2c_set_clock(i2c); + + i2c->adap = octeon_i2c_ops; + i2c->adap.timeout = msecs_to_jiffies(2); + i2c->adap.retries = 5; + i2c->adap.bus_recovery_info = &octeon_i2c_recovery_info; + i2c->adap.dev.parent = &pdev->dev; + i2c->adap.dev.of_node = node; + i2c_set_adapdata(&i2c->adap, i2c); + platform_set_drvdata(pdev, i2c); + + result = i2c_add_adapter(&i2c->adap); + if (result < 0) + goto out; + dev_info(i2c->dev, "probed\n"); + return 0; + +out: + return result; +}; + +static void octeon_i2c_remove(struct platform_device *pdev) +{ + struct octeon_i2c *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adap); +}; + +static const struct of_device_id octeon_i2c_match[] = { + { .compatible = "cavium,octeon-3860-twsi", }, + { .compatible = "cavium,octeon-7890-twsi", }, + {}, +}; +MODULE_DEVICE_TABLE(of, octeon_i2c_match); + +static struct platform_driver octeon_i2c_driver = { + .probe = octeon_i2c_probe, + .remove_new = octeon_i2c_remove, + .driver = { + .name = DRV_NAME, + .of_match_table = octeon_i2c_match, + }, +}; + +module_platform_driver(octeon_i2c_driver); + +MODULE_AUTHOR("Michael Lawnick <michael.lawnick.ext@nsn.com>"); +MODULE_DESCRIPTION("I2C-Bus adapter for Cavium OCTEON processors"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c new file mode 100644 index 000000000..58fd6fa3e --- /dev/null +++ b/drivers/i2c/busses/i2c-omap.c @@ -0,0 +1,1614 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * TI OMAP I2C master mode driver + * + * Copyright (C) 2003 MontaVista Software, Inc. + * Copyright (C) 2005 Nokia Corporation + * Copyright (C) 2004 - 2007 Texas Instruments. + * + * Originally written by MontaVista Software, Inc. + * Additional contributions by: + * Tony Lindgren <tony@atomide.com> + * Imre Deak <imre.deak@nokia.com> + * Juha Yrjölä <juha.yrjola@solidboot.com> + * Syed Khasim <x0khasim@ti.com> + * Nishant Menon <nm@ti.com> + */ + +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/completion.h> +#include <linux/platform_device.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/slab.h> +#include <linux/platform_data/i2c-omap.h> +#include <linux/pm_runtime.h> +#include <linux/pinctrl/consumer.h> + +/* I2C controller revisions */ +#define OMAP_I2C_OMAP1_REV_2 0x20 + +/* I2C controller revisions present on specific hardware */ +#define OMAP_I2C_REV_ON_2430 0x00000036 +#define OMAP_I2C_REV_ON_3430_3530 0x0000003C +#define OMAP_I2C_REV_ON_3630 0x00000040 +#define OMAP_I2C_REV_ON_4430_PLUS 0x50400002 + +/* timeout waiting for the controller to respond */ +#define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000)) + +/* timeout for pm runtime autosuspend */ +#define OMAP_I2C_PM_TIMEOUT 1000 /* ms */ + +/* timeout for making decision on bus free status */ +#define OMAP_I2C_BUS_FREE_TIMEOUT (msecs_to_jiffies(10)) + +/* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */ +enum { + OMAP_I2C_REV_REG = 0, + OMAP_I2C_IE_REG, + OMAP_I2C_STAT_REG, + OMAP_I2C_IV_REG, + OMAP_I2C_WE_REG, + OMAP_I2C_SYSS_REG, + OMAP_I2C_BUF_REG, + OMAP_I2C_CNT_REG, + OMAP_I2C_DATA_REG, + OMAP_I2C_SYSC_REG, + OMAP_I2C_CON_REG, + OMAP_I2C_OA_REG, + OMAP_I2C_SA_REG, + OMAP_I2C_PSC_REG, + OMAP_I2C_SCLL_REG, + OMAP_I2C_SCLH_REG, + OMAP_I2C_SYSTEST_REG, + OMAP_I2C_BUFSTAT_REG, + /* only on OMAP4430 */ + OMAP_I2C_IP_V2_REVNB_LO, + OMAP_I2C_IP_V2_REVNB_HI, + OMAP_I2C_IP_V2_IRQSTATUS_RAW, + OMAP_I2C_IP_V2_IRQENABLE_SET, + OMAP_I2C_IP_V2_IRQENABLE_CLR, +}; + +/* I2C Interrupt Enable Register (OMAP_I2C_IE): */ +#define OMAP_I2C_IE_XDR (1 << 14) /* TX Buffer drain int enable */ +#define OMAP_I2C_IE_RDR (1 << 13) /* RX Buffer drain int enable */ +#define OMAP_I2C_IE_XRDY (1 << 4) /* TX data ready int enable */ +#define OMAP_I2C_IE_RRDY (1 << 3) /* RX data ready int enable */ +#define OMAP_I2C_IE_ARDY (1 << 2) /* Access ready int enable */ +#define OMAP_I2C_IE_NACK (1 << 1) /* No ack interrupt enable */ +#define OMAP_I2C_IE_AL (1 << 0) /* Arbitration lost int ena */ + +/* I2C Status Register (OMAP_I2C_STAT): */ +#define OMAP_I2C_STAT_XDR (1 << 14) /* TX Buffer draining */ +#define OMAP_I2C_STAT_RDR (1 << 13) /* RX Buffer draining */ +#define OMAP_I2C_STAT_BB (1 << 12) /* Bus busy */ +#define OMAP_I2C_STAT_ROVR (1 << 11) /* Receive overrun */ +#define OMAP_I2C_STAT_XUDF (1 << 10) /* Transmit underflow */ +#define OMAP_I2C_STAT_AAS (1 << 9) /* Address as slave */ +#define OMAP_I2C_STAT_BF (1 << 8) /* Bus Free */ +#define OMAP_I2C_STAT_XRDY (1 << 4) /* Transmit data ready */ +#define OMAP_I2C_STAT_RRDY (1 << 3) /* Receive data ready */ +#define OMAP_I2C_STAT_ARDY (1 << 2) /* Register access ready */ +#define OMAP_I2C_STAT_NACK (1 << 1) /* No ack interrupt enable */ +#define OMAP_I2C_STAT_AL (1 << 0) /* Arbitration lost int ena */ + +/* I2C WE wakeup enable register */ +#define OMAP_I2C_WE_XDR_WE (1 << 14) /* TX drain wakup */ +#define OMAP_I2C_WE_RDR_WE (1 << 13) /* RX drain wakeup */ +#define OMAP_I2C_WE_AAS_WE (1 << 9) /* Address as slave wakeup*/ +#define OMAP_I2C_WE_BF_WE (1 << 8) /* Bus free wakeup */ +#define OMAP_I2C_WE_STC_WE (1 << 6) /* Start condition wakeup */ +#define OMAP_I2C_WE_GC_WE (1 << 5) /* General call wakeup */ +#define OMAP_I2C_WE_DRDY_WE (1 << 3) /* TX/RX data ready wakeup */ +#define OMAP_I2C_WE_ARDY_WE (1 << 2) /* Reg access ready wakeup */ +#define OMAP_I2C_WE_NACK_WE (1 << 1) /* No acknowledgment wakeup */ +#define OMAP_I2C_WE_AL_WE (1 << 0) /* Arbitration lost wakeup */ + +#define OMAP_I2C_WE_ALL (OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \ + OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \ + OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \ + OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \ + OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE) + +/* I2C Buffer Configuration Register (OMAP_I2C_BUF): */ +#define OMAP_I2C_BUF_RDMA_EN (1 << 15) /* RX DMA channel enable */ +#define OMAP_I2C_BUF_RXFIF_CLR (1 << 14) /* RX FIFO Clear */ +#define OMAP_I2C_BUF_XDMA_EN (1 << 7) /* TX DMA channel enable */ +#define OMAP_I2C_BUF_TXFIF_CLR (1 << 6) /* TX FIFO Clear */ + +/* I2C Configuration Register (OMAP_I2C_CON): */ +#define OMAP_I2C_CON_EN (1 << 15) /* I2C module enable */ +#define OMAP_I2C_CON_BE (1 << 14) /* Big endian mode */ +#define OMAP_I2C_CON_OPMODE_HS (1 << 12) /* High Speed support */ +#define OMAP_I2C_CON_STB (1 << 11) /* Start byte mode (master) */ +#define OMAP_I2C_CON_MST (1 << 10) /* Master/slave mode */ +#define OMAP_I2C_CON_TRX (1 << 9) /* TX/RX mode (master only) */ +#define OMAP_I2C_CON_XA (1 << 8) /* Expand address */ +#define OMAP_I2C_CON_RM (1 << 2) /* Repeat mode (master only) */ +#define OMAP_I2C_CON_STP (1 << 1) /* Stop cond (master only) */ +#define OMAP_I2C_CON_STT (1 << 0) /* Start condition (master) */ + +/* I2C SCL time value when Master */ +#define OMAP_I2C_SCLL_HSSCLL 8 +#define OMAP_I2C_SCLH_HSSCLH 8 + +/* I2C System Test Register (OMAP_I2C_SYSTEST): */ +#define OMAP_I2C_SYSTEST_ST_EN (1 << 15) /* System test enable */ +#define OMAP_I2C_SYSTEST_FREE (1 << 14) /* Free running mode */ +#define OMAP_I2C_SYSTEST_TMODE_MASK (3 << 12) /* Test mode select */ +#define OMAP_I2C_SYSTEST_TMODE_SHIFT (12) /* Test mode select */ +/* Functional mode */ +#define OMAP_I2C_SYSTEST_SCL_I_FUNC (1 << 8) /* SCL line input value */ +#define OMAP_I2C_SYSTEST_SCL_O_FUNC (1 << 7) /* SCL line output value */ +#define OMAP_I2C_SYSTEST_SDA_I_FUNC (1 << 6) /* SDA line input value */ +#define OMAP_I2C_SYSTEST_SDA_O_FUNC (1 << 5) /* SDA line output value */ +/* SDA/SCL IO mode */ +#define OMAP_I2C_SYSTEST_SCL_I (1 << 3) /* SCL line sense in */ +#define OMAP_I2C_SYSTEST_SCL_O (1 << 2) /* SCL line drive out */ +#define OMAP_I2C_SYSTEST_SDA_I (1 << 1) /* SDA line sense in */ +#define OMAP_I2C_SYSTEST_SDA_O (1 << 0) /* SDA line drive out */ + +/* OCP_SYSSTATUS bit definitions */ +#define SYSS_RESETDONE_MASK (1 << 0) + +/* OCP_SYSCONFIG bit definitions */ +#define SYSC_CLOCKACTIVITY_MASK (0x3 << 8) +#define SYSC_SIDLEMODE_MASK (0x3 << 3) +#define SYSC_ENAWAKEUP_MASK (1 << 2) +#define SYSC_SOFTRESET_MASK (1 << 1) +#define SYSC_AUTOIDLE_MASK (1 << 0) + +#define SYSC_IDLEMODE_SMART 0x2 +#define SYSC_CLOCKACTIVITY_FCLK 0x2 + +/* Errata definitions */ +#define I2C_OMAP_ERRATA_I207 (1 << 0) +#define I2C_OMAP_ERRATA_I462 (1 << 1) + +#define OMAP_I2C_IP_V2_INTERRUPTS_MASK 0x6FFF + +struct omap_i2c_dev { + struct device *dev; + void __iomem *base; /* virtual */ + int irq; + int reg_shift; /* bit shift for I2C register addresses */ + struct completion cmd_complete; + struct resource *ioarea; + u32 latency; /* maximum mpu wkup latency */ + void (*set_mpu_wkup_lat)(struct device *dev, + long latency); + u32 speed; /* Speed of bus in kHz */ + u32 flags; + u16 scheme; + u16 cmd_err; + u8 *buf; + u8 *regs; + size_t buf_len; + struct i2c_adapter adapter; + u8 threshold; + u8 fifo_size; /* use as flag and value + * fifo_size==0 implies no fifo + * if set, should be trsh+1 + */ + u32 rev; + unsigned b_hw:1; /* bad h/w fixes */ + unsigned bb_valid:1; /* true when BB-bit reflects + * the I2C bus state + */ + unsigned receiver:1; /* true when we're in receiver mode */ + u16 iestate; /* Saved interrupt register */ + u16 pscstate; + u16 scllstate; + u16 sclhstate; + u16 syscstate; + u16 westate; + u16 errata; +}; + +static const u8 reg_map_ip_v1[] = { + [OMAP_I2C_REV_REG] = 0x00, + [OMAP_I2C_IE_REG] = 0x01, + [OMAP_I2C_STAT_REG] = 0x02, + [OMAP_I2C_IV_REG] = 0x03, + [OMAP_I2C_WE_REG] = 0x03, + [OMAP_I2C_SYSS_REG] = 0x04, + [OMAP_I2C_BUF_REG] = 0x05, + [OMAP_I2C_CNT_REG] = 0x06, + [OMAP_I2C_DATA_REG] = 0x07, + [OMAP_I2C_SYSC_REG] = 0x08, + [OMAP_I2C_CON_REG] = 0x09, + [OMAP_I2C_OA_REG] = 0x0a, + [OMAP_I2C_SA_REG] = 0x0b, + [OMAP_I2C_PSC_REG] = 0x0c, + [OMAP_I2C_SCLL_REG] = 0x0d, + [OMAP_I2C_SCLH_REG] = 0x0e, + [OMAP_I2C_SYSTEST_REG] = 0x0f, + [OMAP_I2C_BUFSTAT_REG] = 0x10, +}; + +static const u8 reg_map_ip_v2[] = { + [OMAP_I2C_REV_REG] = 0x04, + [OMAP_I2C_IE_REG] = 0x2c, + [OMAP_I2C_STAT_REG] = 0x28, + [OMAP_I2C_IV_REG] = 0x34, + [OMAP_I2C_WE_REG] = 0x34, + [OMAP_I2C_SYSS_REG] = 0x90, + [OMAP_I2C_BUF_REG] = 0x94, + [OMAP_I2C_CNT_REG] = 0x98, + [OMAP_I2C_DATA_REG] = 0x9c, + [OMAP_I2C_SYSC_REG] = 0x10, + [OMAP_I2C_CON_REG] = 0xa4, + [OMAP_I2C_OA_REG] = 0xa8, + [OMAP_I2C_SA_REG] = 0xac, + [OMAP_I2C_PSC_REG] = 0xb0, + [OMAP_I2C_SCLL_REG] = 0xb4, + [OMAP_I2C_SCLH_REG] = 0xb8, + [OMAP_I2C_SYSTEST_REG] = 0xbC, + [OMAP_I2C_BUFSTAT_REG] = 0xc0, + [OMAP_I2C_IP_V2_REVNB_LO] = 0x00, + [OMAP_I2C_IP_V2_REVNB_HI] = 0x04, + [OMAP_I2C_IP_V2_IRQSTATUS_RAW] = 0x24, + [OMAP_I2C_IP_V2_IRQENABLE_SET] = 0x2c, + [OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30, +}; + +static int omap_i2c_xfer_data(struct omap_i2c_dev *omap); + +static inline void omap_i2c_write_reg(struct omap_i2c_dev *omap, + int reg, u16 val) +{ + writew_relaxed(val, omap->base + + (omap->regs[reg] << omap->reg_shift)); +} + +static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *omap, int reg) +{ + return readw_relaxed(omap->base + + (omap->regs[reg] << omap->reg_shift)); +} + +static void __omap_i2c_init(struct omap_i2c_dev *omap) +{ + + omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, 0); + + /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */ + omap_i2c_write_reg(omap, OMAP_I2C_PSC_REG, omap->pscstate); + + /* SCL low and high time values */ + omap_i2c_write_reg(omap, OMAP_I2C_SCLL_REG, omap->scllstate); + omap_i2c_write_reg(omap, OMAP_I2C_SCLH_REG, omap->sclhstate); + if (omap->rev >= OMAP_I2C_REV_ON_3430_3530) + omap_i2c_write_reg(omap, OMAP_I2C_WE_REG, omap->westate); + + /* Take the I2C module out of reset: */ + omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); + + /* + * NOTE: right after setting CON_EN, STAT_BB could be 0 while the + * bus is busy. It will be changed to 1 on the next IP FCLK clock. + * udelay(1) will be enough to fix that. + */ + + /* + * Don't write to this register if the IE state is 0 as it can + * cause deadlock. + */ + if (omap->iestate) + omap_i2c_write_reg(omap, OMAP_I2C_IE_REG, omap->iestate); +} + +static int omap_i2c_reset(struct omap_i2c_dev *omap) +{ + unsigned long timeout; + u16 sysc; + + if (omap->rev >= OMAP_I2C_OMAP1_REV_2) { + sysc = omap_i2c_read_reg(omap, OMAP_I2C_SYSC_REG); + + /* Disable I2C controller before soft reset */ + omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, + omap_i2c_read_reg(omap, OMAP_I2C_CON_REG) & + ~(OMAP_I2C_CON_EN)); + + omap_i2c_write_reg(omap, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK); + /* For some reason we need to set the EN bit before the + * reset done bit gets set. */ + timeout = jiffies + OMAP_I2C_TIMEOUT; + omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); + while (!(omap_i2c_read_reg(omap, OMAP_I2C_SYSS_REG) & + SYSS_RESETDONE_MASK)) { + if (time_after(jiffies, timeout)) { + dev_warn(omap->dev, "timeout waiting " + "for controller reset\n"); + return -ETIMEDOUT; + } + msleep(1); + } + + /* SYSC register is cleared by the reset; rewrite it */ + omap_i2c_write_reg(omap, OMAP_I2C_SYSC_REG, sysc); + + if (omap->rev > OMAP_I2C_REV_ON_3430_3530) { + /* Schedule I2C-bus monitoring on the next transfer */ + omap->bb_valid = 0; + } + } + + return 0; +} + +static int omap_i2c_init(struct omap_i2c_dev *omap) +{ + u16 psc = 0, scll = 0, sclh = 0; + u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0; + unsigned long fclk_rate = 12000000; + unsigned long internal_clk = 0; + struct clk *fclk; + int error; + + if (omap->rev >= OMAP_I2C_REV_ON_3430_3530) { + /* + * Enabling all wakup sources to stop I2C freezing on + * WFI instruction. + * REVISIT: Some wkup sources might not be needed. + */ + omap->westate = OMAP_I2C_WE_ALL; + } + + if (omap->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) { + /* + * The I2C functional clock is the armxor_ck, so there's + * no need to get "armxor_ck" separately. Now, if OMAP2420 + * always returns 12MHz for the functional clock, we can + * do this bit unconditionally. + */ + fclk = clk_get(omap->dev, "fck"); + if (IS_ERR(fclk)) { + error = PTR_ERR(fclk); + dev_err(omap->dev, "could not get fck: %i\n", error); + + return error; + } + + fclk_rate = clk_get_rate(fclk); + clk_put(fclk); + + /* TRM for 5912 says the I2C clock must be prescaled to be + * between 7 - 12 MHz. The XOR input clock is typically + * 12, 13 or 19.2 MHz. So we should have code that produces: + * + * XOR MHz Divider Prescaler + * 12 1 0 + * 13 2 1 + * 19.2 2 1 + */ + if (fclk_rate > 12000000) + psc = fclk_rate / 12000000; + } + + if (!(omap->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) { + + /* + * HSI2C controller internal clk rate should be 19.2 Mhz for + * HS and for all modes on 2430. On 34xx we can use lower rate + * to get longer filter period for better noise suppression. + * The filter is iclk (fclk for HS) period. + */ + if (omap->speed > 400 || + omap->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK) + internal_clk = 19200; + else if (omap->speed > 100) + internal_clk = 9600; + else + internal_clk = 4000; + fclk = clk_get(omap->dev, "fck"); + if (IS_ERR(fclk)) { + error = PTR_ERR(fclk); + dev_err(omap->dev, "could not get fck: %i\n", error); + + return error; + } + fclk_rate = clk_get_rate(fclk) / 1000; + clk_put(fclk); + + /* Compute prescaler divisor */ + psc = fclk_rate / internal_clk; + psc = psc - 1; + + /* If configured for High Speed */ + if (omap->speed > 400) { + unsigned long scl; + + /* For first phase of HS mode */ + scl = internal_clk / 400; + fsscll = scl - (scl / 3) - 7; + fssclh = (scl / 3) - 5; + + /* For second phase of HS mode */ + scl = fclk_rate / omap->speed; + hsscll = scl - (scl / 3) - 7; + hssclh = (scl / 3) - 5; + } else if (omap->speed > 100) { + unsigned long scl; + + /* Fast mode */ + scl = internal_clk / omap->speed; + fsscll = scl - (scl / 3) - 7; + fssclh = (scl / 3) - 5; + } else { + /* Standard mode */ + fsscll = internal_clk / (omap->speed * 2) - 7; + fssclh = internal_clk / (omap->speed * 2) - 5; + } + scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll; + sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh; + } else { + /* Program desired operating rate */ + fclk_rate /= (psc + 1) * 1000; + if (psc > 2) + psc = 2; + scll = fclk_rate / (omap->speed * 2) - 7 + psc; + sclh = fclk_rate / (omap->speed * 2) - 7 + psc; + } + + omap->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY | + OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK | + OMAP_I2C_IE_AL) | ((omap->fifo_size) ? + (OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0); + + omap->pscstate = psc; + omap->scllstate = scll; + omap->sclhstate = sclh; + + if (omap->rev <= OMAP_I2C_REV_ON_3430_3530) { + /* Not implemented */ + omap->bb_valid = 1; + } + + __omap_i2c_init(omap); + + return 0; +} + +/* + * Try bus recovery, but only if SDA is actually low. + */ +static int omap_i2c_recover_bus(struct omap_i2c_dev *omap) +{ + u16 systest; + + systest = omap_i2c_read_reg(omap, OMAP_I2C_SYSTEST_REG); + if ((systest & OMAP_I2C_SYSTEST_SCL_I_FUNC) && + (systest & OMAP_I2C_SYSTEST_SDA_I_FUNC)) + return 0; /* bus seems to already be fine */ + if (!(systest & OMAP_I2C_SYSTEST_SCL_I_FUNC)) + return -EBUSY; /* recovery would not fix SCL */ + return i2c_recover_bus(&omap->adapter); +} + +/* + * Waiting on Bus Busy + */ +static int omap_i2c_wait_for_bb(struct omap_i2c_dev *omap) +{ + unsigned long timeout; + + timeout = jiffies + OMAP_I2C_TIMEOUT; + while (omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) { + if (time_after(jiffies, timeout)) + return omap_i2c_recover_bus(omap); + msleep(1); + } + + return 0; +} + +/* + * Wait while BB-bit doesn't reflect the I2C bus state + * + * In a multimaster environment, after IP software reset, BB-bit value doesn't + * correspond to the current bus state. It may happen what BB-bit will be 0, + * while the bus is busy due to another I2C master activity. + * Here are BB-bit values after reset: + * SDA SCL BB NOTES + * 0 0 0 1, 2 + * 1 0 0 1, 2 + * 0 1 1 + * 1 1 0 3 + * Later, if IP detect SDA=0 and SCL=1 (ACK) or SDA 1->0 while SCL=1 (START) + * combinations on the bus, it set BB-bit to 1. + * If IP detect SDA 0->1 while SCL=1 (STOP) combination on the bus, + * it set BB-bit to 0 and BF to 1. + * BB and BF bits correctly tracks the bus state while IP is suspended + * BB bit became valid on the next FCLK clock after CON_EN bit set + * + * NOTES: + * 1. Any transfer started when BB=0 and bus is busy wouldn't be + * completed by IP and results in controller timeout. + * 2. Any transfer started when BB=0 and SCL=0 results in IP + * starting to drive SDA low. In that case IP corrupt data + * on the bus. + * 3. Any transfer started in the middle of another master's transfer + * results in unpredictable results and data corruption + */ +static int omap_i2c_wait_for_bb_valid(struct omap_i2c_dev *omap) +{ + unsigned long bus_free_timeout = 0; + unsigned long timeout; + int bus_free = 0; + u16 stat, systest; + + if (omap->bb_valid) + return 0; + + timeout = jiffies + OMAP_I2C_TIMEOUT; + while (1) { + stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG); + /* + * We will see BB or BF event in a case IP had detected any + * activity on the I2C bus. Now IP correctly tracks the bus + * state. BB-bit value is valid. + */ + if (stat & (OMAP_I2C_STAT_BB | OMAP_I2C_STAT_BF)) + break; + + /* + * Otherwise, we must look signals on the bus to make + * the right decision. + */ + systest = omap_i2c_read_reg(omap, OMAP_I2C_SYSTEST_REG); + if ((systest & OMAP_I2C_SYSTEST_SCL_I_FUNC) && + (systest & OMAP_I2C_SYSTEST_SDA_I_FUNC)) { + if (!bus_free) { + bus_free_timeout = jiffies + + OMAP_I2C_BUS_FREE_TIMEOUT; + bus_free = 1; + } + + /* + * SDA and SCL lines was high for 10 ms without bus + * activity detected. The bus is free. Consider + * BB-bit value is valid. + */ + if (time_after(jiffies, bus_free_timeout)) + break; + } else { + bus_free = 0; + } + + if (time_after(jiffies, timeout)) { + /* + * SDA or SCL were low for the entire timeout without + * any activity detected. Most likely, a slave is + * locking up the bus with no master driving the clock. + */ + dev_warn(omap->dev, "timeout waiting for bus ready\n"); + return omap_i2c_recover_bus(omap); + } + + msleep(1); + } + + omap->bb_valid = 1; + return 0; +} + +static void omap_i2c_resize_fifo(struct omap_i2c_dev *omap, u8 size, bool is_rx) +{ + u16 buf; + + if (omap->flags & OMAP_I2C_FLAG_NO_FIFO) + return; + + /* + * Set up notification threshold based on message size. We're doing + * this to try and avoid draining feature as much as possible. Whenever + * we have big messages to transfer (bigger than our total fifo size) + * then we might use draining feature to transfer the remaining bytes. + */ + + omap->threshold = clamp(size, (u8) 1, omap->fifo_size); + + buf = omap_i2c_read_reg(omap, OMAP_I2C_BUF_REG); + + if (is_rx) { + /* Clear RX Threshold */ + buf &= ~(0x3f << 8); + buf |= ((omap->threshold - 1) << 8) | OMAP_I2C_BUF_RXFIF_CLR; + } else { + /* Clear TX Threshold */ + buf &= ~0x3f; + buf |= (omap->threshold - 1) | OMAP_I2C_BUF_TXFIF_CLR; + } + + omap_i2c_write_reg(omap, OMAP_I2C_BUF_REG, buf); + + if (omap->rev < OMAP_I2C_REV_ON_3630) + omap->b_hw = 1; /* Enable hardware fixes */ + + /* calculate wakeup latency constraint for MPU */ + if (omap->set_mpu_wkup_lat != NULL) + omap->latency = (1000000 * omap->threshold) / + (1000 * omap->speed / 8); +} + +static void omap_i2c_wait(struct omap_i2c_dev *omap) +{ + u16 stat; + u16 mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG); + int count = 0; + + do { + stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG); + count++; + } while (!(stat & mask) && count < 5); +} + +/* + * Low level master read/write transaction. + */ +static int omap_i2c_xfer_msg(struct i2c_adapter *adap, + struct i2c_msg *msg, int stop, bool polling) +{ + struct omap_i2c_dev *omap = i2c_get_adapdata(adap); + unsigned long timeout; + u16 w; + int ret; + + dev_dbg(omap->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n", + msg->addr, msg->len, msg->flags, stop); + + omap->receiver = !!(msg->flags & I2C_M_RD); + omap_i2c_resize_fifo(omap, msg->len, omap->receiver); + + omap_i2c_write_reg(omap, OMAP_I2C_SA_REG, msg->addr); + + /* REVISIT: Could the STB bit of I2C_CON be used with probing? */ + omap->buf = msg->buf; + omap->buf_len = msg->len; + + /* make sure writes to omap->buf_len are ordered */ + barrier(); + + omap_i2c_write_reg(omap, OMAP_I2C_CNT_REG, omap->buf_len); + + /* Clear the FIFO Buffers */ + w = omap_i2c_read_reg(omap, OMAP_I2C_BUF_REG); + w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR; + omap_i2c_write_reg(omap, OMAP_I2C_BUF_REG, w); + + if (!polling) + reinit_completion(&omap->cmd_complete); + omap->cmd_err = 0; + + w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT; + + /* High speed configuration */ + if (omap->speed > 400) + w |= OMAP_I2C_CON_OPMODE_HS; + + if (msg->flags & I2C_M_STOP) + stop = 1; + if (msg->flags & I2C_M_TEN) + w |= OMAP_I2C_CON_XA; + if (!(msg->flags & I2C_M_RD)) + w |= OMAP_I2C_CON_TRX; + + if (!omap->b_hw && stop) + w |= OMAP_I2C_CON_STP; + /* + * NOTE: STAT_BB bit could became 1 here if another master occupy + * the bus. IP successfully complete transfer when the bus will be + * free again (BB reset to 0). + */ + omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, w); + + /* + * Don't write stt and stp together on some hardware. + */ + if (omap->b_hw && stop) { + unsigned long delay = jiffies + OMAP_I2C_TIMEOUT; + u16 con = omap_i2c_read_reg(omap, OMAP_I2C_CON_REG); + while (con & OMAP_I2C_CON_STT) { + con = omap_i2c_read_reg(omap, OMAP_I2C_CON_REG); + + /* Let the user know if i2c is in a bad state */ + if (time_after(jiffies, delay)) { + dev_err(omap->dev, "controller timed out " + "waiting for start condition to finish\n"); + return -ETIMEDOUT; + } + cpu_relax(); + } + + w |= OMAP_I2C_CON_STP; + w &= ~OMAP_I2C_CON_STT; + omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, w); + } + + /* + * REVISIT: We should abort the transfer on signals, but the bus goes + * into arbitration and we're currently unable to recover from it. + */ + if (!polling) { + timeout = wait_for_completion_timeout(&omap->cmd_complete, + OMAP_I2C_TIMEOUT); + } else { + do { + omap_i2c_wait(omap); + ret = omap_i2c_xfer_data(omap); + } while (ret == -EAGAIN); + + timeout = !ret; + } + + if (timeout == 0) { + dev_err(omap->dev, "controller timed out\n"); + omap_i2c_reset(omap); + __omap_i2c_init(omap); + return -ETIMEDOUT; + } + + if (likely(!omap->cmd_err)) + return 0; + + /* We have an error */ + if (omap->cmd_err & (OMAP_I2C_STAT_ROVR | OMAP_I2C_STAT_XUDF)) { + omap_i2c_reset(omap); + __omap_i2c_init(omap); + return -EIO; + } + + if (omap->cmd_err & OMAP_I2C_STAT_AL) + return -EAGAIN; + + if (omap->cmd_err & OMAP_I2C_STAT_NACK) { + if (msg->flags & I2C_M_IGNORE_NAK) + return 0; + + w = omap_i2c_read_reg(omap, OMAP_I2C_CON_REG); + w |= OMAP_I2C_CON_STP; + omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, w); + return -EREMOTEIO; + } + return -EIO; +} + + +/* + * Prepare controller for a transaction and call omap_i2c_xfer_msg + * to do the work during IRQ processing. + */ +static int +omap_i2c_xfer_common(struct i2c_adapter *adap, struct i2c_msg msgs[], int num, + bool polling) +{ + struct omap_i2c_dev *omap = i2c_get_adapdata(adap); + int i; + int r; + + r = pm_runtime_get_sync(omap->dev); + if (r < 0) + goto out; + + r = omap_i2c_wait_for_bb_valid(omap); + if (r < 0) + goto out; + + r = omap_i2c_wait_for_bb(omap); + if (r < 0) + goto out; + + if (omap->set_mpu_wkup_lat != NULL) + omap->set_mpu_wkup_lat(omap->dev, omap->latency); + + for (i = 0; i < num; i++) { + r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)), + polling); + if (r != 0) + break; + } + + if (r == 0) + r = num; + + omap_i2c_wait_for_bb(omap); + + if (omap->set_mpu_wkup_lat != NULL) + omap->set_mpu_wkup_lat(omap->dev, -1); + +out: + pm_runtime_mark_last_busy(omap->dev); + pm_runtime_put_autosuspend(omap->dev); + return r; +} + +static int +omap_i2c_xfer_irq(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + return omap_i2c_xfer_common(adap, msgs, num, false); +} + +static int +omap_i2c_xfer_polling(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + return omap_i2c_xfer_common(adap, msgs, num, true); +} + +static u32 +omap_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | + I2C_FUNC_PROTOCOL_MANGLING; +} + +static inline void +omap_i2c_complete_cmd(struct omap_i2c_dev *omap, u16 err) +{ + omap->cmd_err |= err; + complete(&omap->cmd_complete); +} + +static inline void +omap_i2c_ack_stat(struct omap_i2c_dev *omap, u16 stat) +{ + omap_i2c_write_reg(omap, OMAP_I2C_STAT_REG, stat); +} + +static inline void i2c_omap_errata_i207(struct omap_i2c_dev *omap, u16 stat) +{ + /* + * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8) + * Not applicable for OMAP4. + * Under certain rare conditions, RDR could be set again + * when the bus is busy, then ignore the interrupt and + * clear the interrupt. + */ + if (stat & OMAP_I2C_STAT_RDR) { + /* Step 1: If RDR is set, clear it */ + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_RDR); + + /* Step 2: */ + if (!(omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG) + & OMAP_I2C_STAT_BB)) { + + /* Step 3: */ + if (omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG) + & OMAP_I2C_STAT_RDR) { + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_RDR); + dev_dbg(omap->dev, "RDR when bus is busy.\n"); + } + + } + } +} + +/* rev1 devices are apparently only on some 15xx */ +#ifdef CONFIG_ARCH_OMAP15XX + +static irqreturn_t +omap_i2c_omap1_isr(int this_irq, void *dev_id) +{ + struct omap_i2c_dev *omap = dev_id; + u16 iv, w; + + if (pm_runtime_suspended(omap->dev)) + return IRQ_NONE; + + iv = omap_i2c_read_reg(omap, OMAP_I2C_IV_REG); + switch (iv) { + case 0x00: /* None */ + break; + case 0x01: /* Arbitration lost */ + dev_err(omap->dev, "Arbitration lost\n"); + omap_i2c_complete_cmd(omap, OMAP_I2C_STAT_AL); + break; + case 0x02: /* No acknowledgement */ + omap_i2c_complete_cmd(omap, OMAP_I2C_STAT_NACK); + omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP); + break; + case 0x03: /* Register access ready */ + omap_i2c_complete_cmd(omap, 0); + break; + case 0x04: /* Receive data ready */ + if (omap->buf_len) { + w = omap_i2c_read_reg(omap, OMAP_I2C_DATA_REG); + *omap->buf++ = w; + omap->buf_len--; + if (omap->buf_len) { + *omap->buf++ = w >> 8; + omap->buf_len--; + } + } else + dev_err(omap->dev, "RRDY IRQ while no data requested\n"); + break; + case 0x05: /* Transmit data ready */ + if (omap->buf_len) { + w = *omap->buf++; + omap->buf_len--; + if (omap->buf_len) { + w |= *omap->buf++ << 8; + omap->buf_len--; + } + omap_i2c_write_reg(omap, OMAP_I2C_DATA_REG, w); + } else + dev_err(omap->dev, "XRDY IRQ while no data to send\n"); + break; + default: + return IRQ_NONE; + } + + return IRQ_HANDLED; +} +#else +#define omap_i2c_omap1_isr NULL +#endif + +/* + * OMAP3430 Errata i462: When an XRDY/XDR is hit, wait for XUDF before writing + * data to DATA_REG. Otherwise some data bytes can be lost while transferring + * them from the memory to the I2C interface. + */ +static int errata_omap3_i462(struct omap_i2c_dev *omap) +{ + unsigned long timeout = 10000; + u16 stat; + + do { + stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG); + if (stat & OMAP_I2C_STAT_XUDF) + break; + + if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) { + omap_i2c_ack_stat(omap, (OMAP_I2C_STAT_XRDY | + OMAP_I2C_STAT_XDR)); + if (stat & OMAP_I2C_STAT_NACK) { + omap->cmd_err |= OMAP_I2C_STAT_NACK; + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_NACK); + } + + if (stat & OMAP_I2C_STAT_AL) { + dev_err(omap->dev, "Arbitration lost\n"); + omap->cmd_err |= OMAP_I2C_STAT_AL; + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_AL); + } + + return -EIO; + } + + cpu_relax(); + } while (--timeout); + + if (!timeout) { + dev_err(omap->dev, "timeout waiting on XUDF bit\n"); + return 0; + } + + return 0; +} + +static void omap_i2c_receive_data(struct omap_i2c_dev *omap, u8 num_bytes, + bool is_rdr) +{ + u16 w; + + while (num_bytes--) { + w = omap_i2c_read_reg(omap, OMAP_I2C_DATA_REG); + *omap->buf++ = w; + omap->buf_len--; + + /* + * Data reg in 2430, omap3 and + * omap4 is 8 bit wide + */ + if (omap->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) { + *omap->buf++ = w >> 8; + omap->buf_len--; + } + } +} + +static int omap_i2c_transmit_data(struct omap_i2c_dev *omap, u8 num_bytes, + bool is_xdr) +{ + u16 w; + + while (num_bytes--) { + w = *omap->buf++; + omap->buf_len--; + + /* + * Data reg in 2430, omap3 and + * omap4 is 8 bit wide + */ + if (omap->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) { + w |= *omap->buf++ << 8; + omap->buf_len--; + } + + if (omap->errata & I2C_OMAP_ERRATA_I462) { + int ret; + + ret = errata_omap3_i462(omap); + if (ret < 0) + return ret; + } + + omap_i2c_write_reg(omap, OMAP_I2C_DATA_REG, w); + } + + return 0; +} + +static irqreturn_t +omap_i2c_isr(int irq, void *dev_id) +{ + struct omap_i2c_dev *omap = dev_id; + irqreturn_t ret = IRQ_HANDLED; + u16 mask; + u16 stat; + + stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG); + mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG) & ~OMAP_I2C_STAT_NACK; + + if (stat & mask) + ret = IRQ_WAKE_THREAD; + + return ret; +} + +static int omap_i2c_xfer_data(struct omap_i2c_dev *omap) +{ + u16 bits; + u16 stat; + int err = 0, count = 0; + + do { + bits = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG); + stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG); + stat &= bits; + + /* If we're in receiver mode, ignore XDR/XRDY */ + if (omap->receiver) + stat &= ~(OMAP_I2C_STAT_XDR | OMAP_I2C_STAT_XRDY); + else + stat &= ~(OMAP_I2C_STAT_RDR | OMAP_I2C_STAT_RRDY); + + if (!stat) { + /* my work here is done */ + err = -EAGAIN; + break; + } + + dev_dbg(omap->dev, "IRQ (ISR = 0x%04x)\n", stat); + if (count++ == 100) { + dev_warn(omap->dev, "Too much work in one IRQ\n"); + break; + } + + if (stat & OMAP_I2C_STAT_NACK) { + err |= OMAP_I2C_STAT_NACK; + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_NACK); + } + + if (stat & OMAP_I2C_STAT_AL) { + dev_err(omap->dev, "Arbitration lost\n"); + err |= OMAP_I2C_STAT_AL; + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_AL); + } + + /* + * ProDB0017052: Clear ARDY bit twice + */ + if (stat & OMAP_I2C_STAT_ARDY) + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_ARDY); + + if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK | + OMAP_I2C_STAT_AL)) { + omap_i2c_ack_stat(omap, (OMAP_I2C_STAT_RRDY | + OMAP_I2C_STAT_RDR | + OMAP_I2C_STAT_XRDY | + OMAP_I2C_STAT_XDR | + OMAP_I2C_STAT_ARDY)); + break; + } + + if (stat & OMAP_I2C_STAT_RDR) { + u8 num_bytes = 1; + + if (omap->fifo_size) + num_bytes = omap->buf_len; + + if (omap->errata & I2C_OMAP_ERRATA_I207) { + i2c_omap_errata_i207(omap, stat); + num_bytes = (omap_i2c_read_reg(omap, + OMAP_I2C_BUFSTAT_REG) >> 8) & 0x3F; + } + + omap_i2c_receive_data(omap, num_bytes, true); + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_RDR); + continue; + } + + if (stat & OMAP_I2C_STAT_RRDY) { + u8 num_bytes = 1; + + if (omap->threshold) + num_bytes = omap->threshold; + + omap_i2c_receive_data(omap, num_bytes, false); + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_RRDY); + continue; + } + + if (stat & OMAP_I2C_STAT_XDR) { + u8 num_bytes = 1; + int ret; + + if (omap->fifo_size) + num_bytes = omap->buf_len; + + ret = omap_i2c_transmit_data(omap, num_bytes, true); + if (ret < 0) + break; + + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_XDR); + continue; + } + + if (stat & OMAP_I2C_STAT_XRDY) { + u8 num_bytes = 1; + int ret; + + if (omap->threshold) + num_bytes = omap->threshold; + + ret = omap_i2c_transmit_data(omap, num_bytes, false); + if (ret < 0) + break; + + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_XRDY); + continue; + } + + if (stat & OMAP_I2C_STAT_ROVR) { + dev_err(omap->dev, "Receive overrun\n"); + err |= OMAP_I2C_STAT_ROVR; + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_ROVR); + break; + } + + if (stat & OMAP_I2C_STAT_XUDF) { + dev_err(omap->dev, "Transmit underflow\n"); + err |= OMAP_I2C_STAT_XUDF; + omap_i2c_ack_stat(omap, OMAP_I2C_STAT_XUDF); + break; + } + } while (stat); + + return err; +} + +static irqreturn_t +omap_i2c_isr_thread(int this_irq, void *dev_id) +{ + int ret; + struct omap_i2c_dev *omap = dev_id; + + ret = omap_i2c_xfer_data(omap); + if (ret != -EAGAIN) + omap_i2c_complete_cmd(omap, ret); + + return IRQ_HANDLED; +} + +static const struct i2c_algorithm omap_i2c_algo = { + .master_xfer = omap_i2c_xfer_irq, + .master_xfer_atomic = omap_i2c_xfer_polling, + .functionality = omap_i2c_func, +}; + +static const struct i2c_adapter_quirks omap_i2c_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN, +}; + +#ifdef CONFIG_OF +static struct omap_i2c_bus_platform_data omap2420_pdata = { + .rev = OMAP_I2C_IP_VERSION_1, + .flags = OMAP_I2C_FLAG_NO_FIFO | + OMAP_I2C_FLAG_SIMPLE_CLOCK | + OMAP_I2C_FLAG_16BIT_DATA_REG | + OMAP_I2C_FLAG_BUS_SHIFT_2, +}; + +static struct omap_i2c_bus_platform_data omap2430_pdata = { + .rev = OMAP_I2C_IP_VERSION_1, + .flags = OMAP_I2C_FLAG_BUS_SHIFT_2 | + OMAP_I2C_FLAG_FORCE_19200_INT_CLK, +}; + +static struct omap_i2c_bus_platform_data omap3_pdata = { + .rev = OMAP_I2C_IP_VERSION_1, + .flags = OMAP_I2C_FLAG_BUS_SHIFT_2, +}; + +static struct omap_i2c_bus_platform_data omap4_pdata = { + .rev = OMAP_I2C_IP_VERSION_2, +}; + +static const struct of_device_id omap_i2c_of_match[] = { + { + .compatible = "ti,omap4-i2c", + .data = &omap4_pdata, + }, + { + .compatible = "ti,omap3-i2c", + .data = &omap3_pdata, + }, + { + .compatible = "ti,omap2430-i2c", + .data = &omap2430_pdata, + }, + { + .compatible = "ti,omap2420-i2c", + .data = &omap2420_pdata, + }, + { }, +}; +MODULE_DEVICE_TABLE(of, omap_i2c_of_match); +#endif + +#define OMAP_I2C_SCHEME(rev) ((rev & 0xc000) >> 14) + +#define OMAP_I2C_REV_SCHEME_0_MAJOR(rev) (rev >> 4) +#define OMAP_I2C_REV_SCHEME_0_MINOR(rev) (rev & 0xf) + +#define OMAP_I2C_REV_SCHEME_1_MAJOR(rev) ((rev & 0x0700) >> 7) +#define OMAP_I2C_REV_SCHEME_1_MINOR(rev) (rev & 0x1f) +#define OMAP_I2C_SCHEME_0 0 +#define OMAP_I2C_SCHEME_1 1 + +static int omap_i2c_get_scl(struct i2c_adapter *adap) +{ + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); + u32 reg; + + reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); + + return reg & OMAP_I2C_SYSTEST_SCL_I_FUNC; +} + +static int omap_i2c_get_sda(struct i2c_adapter *adap) +{ + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); + u32 reg; + + reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); + + return reg & OMAP_I2C_SYSTEST_SDA_I_FUNC; +} + +static void omap_i2c_set_scl(struct i2c_adapter *adap, int val) +{ + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); + u32 reg; + + reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); + if (val) + reg |= OMAP_I2C_SYSTEST_SCL_O; + else + reg &= ~OMAP_I2C_SYSTEST_SCL_O; + omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, reg); +} + +static void omap_i2c_prepare_recovery(struct i2c_adapter *adap) +{ + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); + u32 reg; + + reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); + /* enable test mode */ + reg |= OMAP_I2C_SYSTEST_ST_EN; + /* select SDA/SCL IO mode */ + reg |= 3 << OMAP_I2C_SYSTEST_TMODE_SHIFT; + /* set SCL to high-impedance state (reset value is 0) */ + reg |= OMAP_I2C_SYSTEST_SCL_O; + /* set SDA to high-impedance state (reset value is 0) */ + reg |= OMAP_I2C_SYSTEST_SDA_O; + omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, reg); +} + +static void omap_i2c_unprepare_recovery(struct i2c_adapter *adap) +{ + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); + u32 reg; + + reg = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG); + /* restore reset values */ + reg &= ~OMAP_I2C_SYSTEST_ST_EN; + reg &= ~OMAP_I2C_SYSTEST_TMODE_MASK; + reg &= ~OMAP_I2C_SYSTEST_SCL_O; + reg &= ~OMAP_I2C_SYSTEST_SDA_O; + omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, reg); +} + +static struct i2c_bus_recovery_info omap_i2c_bus_recovery_info = { + .get_scl = omap_i2c_get_scl, + .get_sda = omap_i2c_get_sda, + .set_scl = omap_i2c_set_scl, + .prepare_recovery = omap_i2c_prepare_recovery, + .unprepare_recovery = omap_i2c_unprepare_recovery, + .recover_bus = i2c_generic_scl_recovery, +}; + +static int +omap_i2c_probe(struct platform_device *pdev) +{ + struct omap_i2c_dev *omap; + struct i2c_adapter *adap; + const struct omap_i2c_bus_platform_data *pdata = + dev_get_platdata(&pdev->dev); + struct device_node *node = pdev->dev.of_node; + const struct of_device_id *match; + int irq; + int r; + u32 rev; + u16 minor, major; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + omap = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL); + if (!omap) + return -ENOMEM; + + omap->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(omap->base)) + return PTR_ERR(omap->base); + + match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev); + if (match) { + u32 freq = I2C_MAX_STANDARD_MODE_FREQ; + + pdata = match->data; + omap->flags = pdata->flags; + + of_property_read_u32(node, "clock-frequency", &freq); + /* convert DT freq value in Hz into kHz for speed */ + omap->speed = freq / 1000; + } else if (pdata != NULL) { + omap->speed = pdata->clkrate; + omap->flags = pdata->flags; + omap->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat; + } + + omap->dev = &pdev->dev; + omap->irq = irq; + + platform_set_drvdata(pdev, omap); + init_completion(&omap->cmd_complete); + + omap->reg_shift = (omap->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3; + + pm_runtime_enable(omap->dev); + pm_runtime_set_autosuspend_delay(omap->dev, OMAP_I2C_PM_TIMEOUT); + pm_runtime_use_autosuspend(omap->dev); + + r = pm_runtime_resume_and_get(omap->dev); + if (r < 0) + goto err_disable_pm; + + /* + * Read the Rev hi bit-[15:14] ie scheme this is 1 indicates ver2. + * On omap1/3/2 Offset 4 is IE Reg the bit [15:14] is 0 at reset. + * Also since the omap_i2c_read_reg uses reg_map_ip_* a + * readw_relaxed is done. + */ + rev = readw_relaxed(omap->base + 0x04); + + omap->scheme = OMAP_I2C_SCHEME(rev); + switch (omap->scheme) { + case OMAP_I2C_SCHEME_0: + omap->regs = (u8 *)reg_map_ip_v1; + omap->rev = omap_i2c_read_reg(omap, OMAP_I2C_REV_REG); + minor = OMAP_I2C_REV_SCHEME_0_MAJOR(omap->rev); + major = OMAP_I2C_REV_SCHEME_0_MAJOR(omap->rev); + break; + case OMAP_I2C_SCHEME_1: + default: + omap->regs = (u8 *)reg_map_ip_v2; + rev = (rev << 16) | + omap_i2c_read_reg(omap, OMAP_I2C_IP_V2_REVNB_LO); + minor = OMAP_I2C_REV_SCHEME_1_MINOR(rev); + major = OMAP_I2C_REV_SCHEME_1_MAJOR(rev); + omap->rev = rev; + } + + omap->errata = 0; + + if (omap->rev >= OMAP_I2C_REV_ON_2430 && + omap->rev < OMAP_I2C_REV_ON_4430_PLUS) + omap->errata |= I2C_OMAP_ERRATA_I207; + + if (omap->rev <= OMAP_I2C_REV_ON_3430_3530) + omap->errata |= I2C_OMAP_ERRATA_I462; + + if (!(omap->flags & OMAP_I2C_FLAG_NO_FIFO)) { + u16 s; + + /* Set up the fifo size - Get total size */ + s = (omap_i2c_read_reg(omap, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3; + omap->fifo_size = 0x8 << s; + + /* + * Set up notification threshold as half the total available + * size. This is to ensure that we can handle the status on int + * call back latencies. + */ + + omap->fifo_size = (omap->fifo_size / 2); + + if (omap->rev < OMAP_I2C_REV_ON_3630) + omap->b_hw = 1; /* Enable hardware fixes */ + + /* calculate wakeup latency constraint for MPU */ + if (omap->set_mpu_wkup_lat != NULL) + omap->latency = (1000000 * omap->fifo_size) / + (1000 * omap->speed / 8); + } + + /* reset ASAP, clearing any IRQs */ + omap_i2c_init(omap); + + if (omap->rev < OMAP_I2C_OMAP1_REV_2) + r = devm_request_irq(&pdev->dev, omap->irq, omap_i2c_omap1_isr, + IRQF_NO_SUSPEND, pdev->name, omap); + else + r = devm_request_threaded_irq(&pdev->dev, omap->irq, + omap_i2c_isr, omap_i2c_isr_thread, + IRQF_NO_SUSPEND | IRQF_ONESHOT, + pdev->name, omap); + + if (r) { + dev_err(omap->dev, "failure requesting irq %i\n", omap->irq); + goto err_unuse_clocks; + } + + adap = &omap->adapter; + i2c_set_adapdata(adap, omap); + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_DEPRECATED; + strscpy(adap->name, "OMAP I2C adapter", sizeof(adap->name)); + adap->algo = &omap_i2c_algo; + adap->quirks = &omap_i2c_quirks; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + adap->bus_recovery_info = &omap_i2c_bus_recovery_info; + + /* i2c device drivers may be active on return from add_adapter() */ + adap->nr = pdev->id; + r = i2c_add_numbered_adapter(adap); + if (r) + goto err_unuse_clocks; + + dev_info(omap->dev, "bus %d rev%d.%d at %d kHz\n", adap->nr, + major, minor, omap->speed); + + pm_runtime_mark_last_busy(omap->dev); + pm_runtime_put_autosuspend(omap->dev); + + return 0; + +err_unuse_clocks: + omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, 0); + pm_runtime_dont_use_autosuspend(omap->dev); + pm_runtime_put_sync(omap->dev); +err_disable_pm: + pm_runtime_disable(&pdev->dev); + + return r; +} + +static void omap_i2c_remove(struct platform_device *pdev) +{ + struct omap_i2c_dev *omap = platform_get_drvdata(pdev); + int ret; + + i2c_del_adapter(&omap->adapter); + + ret = pm_runtime_get_sync(&pdev->dev); + if (ret < 0) + dev_err(omap->dev, "Failed to resume hardware, skip disable\n"); + else + omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, 0); + + pm_runtime_dont_use_autosuspend(&pdev->dev); + pm_runtime_put_sync(&pdev->dev); + pm_runtime_disable(&pdev->dev); +} + +static int __maybe_unused omap_i2c_runtime_suspend(struct device *dev) +{ + struct omap_i2c_dev *omap = dev_get_drvdata(dev); + + omap->iestate = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG); + + if (omap->scheme == OMAP_I2C_SCHEME_0) + omap_i2c_write_reg(omap, OMAP_I2C_IE_REG, 0); + else + omap_i2c_write_reg(omap, OMAP_I2C_IP_V2_IRQENABLE_CLR, + OMAP_I2C_IP_V2_INTERRUPTS_MASK); + + if (omap->rev < OMAP_I2C_OMAP1_REV_2) { + omap_i2c_read_reg(omap, OMAP_I2C_IV_REG); /* Read clears */ + } else { + omap_i2c_write_reg(omap, OMAP_I2C_STAT_REG, omap->iestate); + + /* Flush posted write */ + omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG); + } + + pinctrl_pm_select_sleep_state(dev); + + return 0; +} + +static int __maybe_unused omap_i2c_runtime_resume(struct device *dev) +{ + struct omap_i2c_dev *omap = dev_get_drvdata(dev); + + pinctrl_pm_select_default_state(dev); + + if (!omap->regs) + return 0; + + __omap_i2c_init(omap); + + return 0; +} + +static const struct dev_pm_ops omap_i2c_pm_ops = { + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) + SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend, + omap_i2c_runtime_resume, NULL) +}; + +static struct platform_driver omap_i2c_driver = { + .probe = omap_i2c_probe, + .remove_new = omap_i2c_remove, + .driver = { + .name = "omap_i2c", + .pm = &omap_i2c_pm_ops, + .of_match_table = of_match_ptr(omap_i2c_of_match), + }, +}; + +/* I2C may be needed to bring up other drivers */ +static int __init +omap_i2c_init_driver(void) +{ + return platform_driver_register(&omap_i2c_driver); +} +subsys_initcall(omap_i2c_init_driver); + +static void __exit omap_i2c_exit_driver(void) +{ + platform_driver_unregister(&omap_i2c_driver); +} +module_exit(omap_i2c_exit_driver); + +MODULE_AUTHOR("MontaVista Software, Inc. (and others)"); +MODULE_DESCRIPTION("TI OMAP I2C bus adapter"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:omap_i2c"); diff --git a/drivers/i2c/busses/i2c-opal.c b/drivers/i2c/busses/i2c-opal.c new file mode 100644 index 000000000..17ef87d50 --- /dev/null +++ b/drivers/i2c/busses/i2c-opal.c @@ -0,0 +1,276 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * IBM OPAL I2C driver + * Copyright (C) 2014 IBM + */ + +#include <linux/device.h> +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#include <asm/firmware.h> +#include <asm/opal.h> + +static int i2c_opal_translate_error(int rc) +{ + switch (rc) { + case OPAL_NO_MEM: + return -ENOMEM; + case OPAL_PARAMETER: + return -EINVAL; + case OPAL_I2C_ARBT_LOST: + return -EAGAIN; + case OPAL_I2C_TIMEOUT: + return -ETIMEDOUT; + case OPAL_I2C_NACK_RCVD: + return -ENXIO; + case OPAL_I2C_STOP_ERR: + return -EBUSY; + default: + return -EIO; + } +} + +static int i2c_opal_send_request(u32 bus_id, struct opal_i2c_request *req) +{ + struct opal_msg msg; + int token, rc; + + token = opal_async_get_token_interruptible(); + if (token < 0) { + if (token != -ERESTARTSYS) + pr_err("Failed to get the async token\n"); + + return token; + } + + rc = opal_i2c_request(token, bus_id, req); + if (rc != OPAL_ASYNC_COMPLETION) { + rc = i2c_opal_translate_error(rc); + goto exit; + } + + rc = opal_async_wait_response(token, &msg); + if (rc) + goto exit; + + rc = opal_get_async_rc(msg); + if (rc != OPAL_SUCCESS) { + rc = i2c_opal_translate_error(rc); + goto exit; + } + +exit: + opal_async_release_token(token); + return rc; +} + +static int i2c_opal_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + unsigned long opal_id = (unsigned long)adap->algo_data; + struct opal_i2c_request req; + int rc, i; + + /* We only support fairly simple combinations here of one + * or two messages + */ + memset(&req, 0, sizeof(req)); + switch(num) { + case 1: + req.type = (msgs[0].flags & I2C_M_RD) ? + OPAL_I2C_RAW_READ : OPAL_I2C_RAW_WRITE; + req.addr = cpu_to_be16(msgs[0].addr); + req.size = cpu_to_be32(msgs[0].len); + req.buffer_ra = cpu_to_be64(__pa(msgs[0].buf)); + break; + case 2: + req.type = (msgs[1].flags & I2C_M_RD) ? + OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE; + req.addr = cpu_to_be16(msgs[0].addr); + req.subaddr_sz = msgs[0].len; + for (i = 0; i < msgs[0].len; i++) + req.subaddr = (req.subaddr << 8) | msgs[0].buf[i]; + req.subaddr = cpu_to_be32(req.subaddr); + req.size = cpu_to_be32(msgs[1].len); + req.buffer_ra = cpu_to_be64(__pa(msgs[1].buf)); + break; + } + + rc = i2c_opal_send_request(opal_id, &req); + if (rc) + return rc; + + return num; +} + +static int i2c_opal_smbus_xfer(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data *data) +{ + unsigned long opal_id = (unsigned long)adap->algo_data; + struct opal_i2c_request req; + u8 local[2]; + int rc; + + memset(&req, 0, sizeof(req)); + + req.addr = cpu_to_be16(addr); + switch (size) { + case I2C_SMBUS_BYTE: + req.buffer_ra = cpu_to_be64(__pa(&data->byte)); + req.size = cpu_to_be32(1); + fallthrough; + case I2C_SMBUS_QUICK: + req.type = (read_write == I2C_SMBUS_READ) ? + OPAL_I2C_RAW_READ : OPAL_I2C_RAW_WRITE; + break; + case I2C_SMBUS_BYTE_DATA: + req.buffer_ra = cpu_to_be64(__pa(&data->byte)); + req.size = cpu_to_be32(1); + req.subaddr = cpu_to_be32(command); + req.subaddr_sz = 1; + req.type = (read_write == I2C_SMBUS_READ) ? + OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE; + break; + case I2C_SMBUS_WORD_DATA: + if (!read_write) { + local[0] = data->word & 0xff; + local[1] = (data->word >> 8) & 0xff; + } + req.buffer_ra = cpu_to_be64(__pa(local)); + req.size = cpu_to_be32(2); + req.subaddr = cpu_to_be32(command); + req.subaddr_sz = 1; + req.type = (read_write == I2C_SMBUS_READ) ? + OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE; + break; + case I2C_SMBUS_I2C_BLOCK_DATA: + req.buffer_ra = cpu_to_be64(__pa(&data->block[1])); + req.size = cpu_to_be32(data->block[0]); + req.subaddr = cpu_to_be32(command); + req.subaddr_sz = 1; + req.type = (read_write == I2C_SMBUS_READ) ? + OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE; + break; + default: + return -EINVAL; + } + + rc = i2c_opal_send_request(opal_id, &req); + if (!rc && read_write && size == I2C_SMBUS_WORD_DATA) { + data->word = ((u16)local[1]) << 8; + data->word |= local[0]; + } + + return rc; +} + +static u32 i2c_opal_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_I2C_BLOCK; +} + +static const struct i2c_algorithm i2c_opal_algo = { + .master_xfer = i2c_opal_master_xfer, + .smbus_xfer = i2c_opal_smbus_xfer, + .functionality = i2c_opal_func, +}; + +/* + * For two messages, we basically support simple smbus transactions of a + * write-then-anything. + */ +static const struct i2c_adapter_quirks i2c_opal_quirks = { + .flags = I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | I2C_AQ_COMB_SAME_ADDR, + .max_comb_1st_msg_len = 4, +}; + +static int i2c_opal_probe(struct platform_device *pdev) +{ + struct i2c_adapter *adapter; + const char *pname; + u32 opal_id; + int rc; + + if (!pdev->dev.of_node) + return -ENODEV; + + rc = of_property_read_u32(pdev->dev.of_node, "ibm,opal-id", &opal_id); + if (rc) { + dev_err(&pdev->dev, "Missing ibm,opal-id property !\n"); + return -EIO; + } + + adapter = devm_kzalloc(&pdev->dev, sizeof(*adapter), GFP_KERNEL); + if (!adapter) + return -ENOMEM; + + adapter->algo = &i2c_opal_algo; + adapter->algo_data = (void *)(unsigned long)opal_id; + adapter->quirks = &i2c_opal_quirks; + adapter->dev.parent = &pdev->dev; + adapter->dev.of_node = of_node_get(pdev->dev.of_node); + pname = of_get_property(pdev->dev.of_node, "ibm,port-name", NULL); + if (pname) + strscpy(adapter->name, pname, sizeof(adapter->name)); + else + strscpy(adapter->name, "opal", sizeof(adapter->name)); + + platform_set_drvdata(pdev, adapter); + rc = i2c_add_adapter(adapter); + if (rc) + dev_err(&pdev->dev, "Failed to register the i2c adapter\n"); + + return rc; +} + +static void i2c_opal_remove(struct platform_device *pdev) +{ + struct i2c_adapter *adapter = platform_get_drvdata(pdev); + + i2c_del_adapter(adapter); +} + +static const struct of_device_id i2c_opal_of_match[] = { + { + .compatible = "ibm,opal-i2c", + }, + { } +}; +MODULE_DEVICE_TABLE(of, i2c_opal_of_match); + +static struct platform_driver i2c_opal_driver = { + .probe = i2c_opal_probe, + .remove_new = i2c_opal_remove, + .driver = { + .name = "i2c-opal", + .of_match_table = i2c_opal_of_match, + }, +}; + +static int __init i2c_opal_init(void) +{ + if (!firmware_has_feature(FW_FEATURE_OPAL)) + return -ENODEV; + + return platform_driver_register(&i2c_opal_driver); +} +module_init(i2c_opal_init); + +static void __exit i2c_opal_exit(void) +{ + return platform_driver_unregister(&i2c_opal_driver); +} +module_exit(i2c_opal_exit); + +MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>"); +MODULE_DESCRIPTION("IBM OPAL I2C driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-owl.c b/drivers/i2c/busses/i2c-owl.c new file mode 100644 index 000000000..777f1a027 --- /dev/null +++ b/drivers/i2c/busses/i2c-owl.c @@ -0,0 +1,522 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Actions Semiconductor Owl SoC's I2C driver + * + * Copyright (c) 2014 Actions Semi Inc. + * Author: David Liu <liuwei@actions-semi.com> + * + * Copyright (c) 2018 Linaro Ltd. + * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> + +/* I2C registers */ +#define OWL_I2C_REG_CTL 0x0000 +#define OWL_I2C_REG_CLKDIV 0x0004 +#define OWL_I2C_REG_STAT 0x0008 +#define OWL_I2C_REG_ADDR 0x000C +#define OWL_I2C_REG_TXDAT 0x0010 +#define OWL_I2C_REG_RXDAT 0x0014 +#define OWL_I2C_REG_CMD 0x0018 +#define OWL_I2C_REG_FIFOCTL 0x001C +#define OWL_I2C_REG_FIFOSTAT 0x0020 +#define OWL_I2C_REG_DATCNT 0x0024 +#define OWL_I2C_REG_RCNT 0x0028 + +/* I2Cx_CTL Bit Mask */ +#define OWL_I2C_CTL_RB BIT(1) +#define OWL_I2C_CTL_GBCC(x) (((x) & 0x3) << 2) +#define OWL_I2C_CTL_GBCC_NONE OWL_I2C_CTL_GBCC(0) +#define OWL_I2C_CTL_GBCC_START OWL_I2C_CTL_GBCC(1) +#define OWL_I2C_CTL_GBCC_STOP OWL_I2C_CTL_GBCC(2) +#define OWL_I2C_CTL_GBCC_RSTART OWL_I2C_CTL_GBCC(3) +#define OWL_I2C_CTL_IRQE BIT(5) +#define OWL_I2C_CTL_EN BIT(7) +#define OWL_I2C_CTL_AE BIT(8) +#define OWL_I2C_CTL_SHSM BIT(10) + +#define OWL_I2C_DIV_FACTOR(x) ((x) & 0xff) + +/* I2Cx_STAT Bit Mask */ +#define OWL_I2C_STAT_RACK BIT(0) +#define OWL_I2C_STAT_BEB BIT(1) +#define OWL_I2C_STAT_IRQP BIT(2) +#define OWL_I2C_STAT_LAB BIT(3) +#define OWL_I2C_STAT_STPD BIT(4) +#define OWL_I2C_STAT_STAD BIT(5) +#define OWL_I2C_STAT_BBB BIT(6) +#define OWL_I2C_STAT_TCB BIT(7) +#define OWL_I2C_STAT_LBST BIT(8) +#define OWL_I2C_STAT_SAMB BIT(9) +#define OWL_I2C_STAT_SRGC BIT(10) + +/* I2Cx_CMD Bit Mask */ +#define OWL_I2C_CMD_SBE BIT(0) +#define OWL_I2C_CMD_RBE BIT(4) +#define OWL_I2C_CMD_DE BIT(8) +#define OWL_I2C_CMD_NS BIT(9) +#define OWL_I2C_CMD_SE BIT(10) +#define OWL_I2C_CMD_MSS BIT(11) +#define OWL_I2C_CMD_WRS BIT(12) +#define OWL_I2C_CMD_SECL BIT(15) + +#define OWL_I2C_CMD_AS(x) (((x) & 0x7) << 1) +#define OWL_I2C_CMD_SAS(x) (((x) & 0x7) << 5) + +/* I2Cx_FIFOCTL Bit Mask */ +#define OWL_I2C_FIFOCTL_NIB BIT(0) +#define OWL_I2C_FIFOCTL_RFR BIT(1) +#define OWL_I2C_FIFOCTL_TFR BIT(2) + +/* I2Cc_FIFOSTAT Bit Mask */ +#define OWL_I2C_FIFOSTAT_CECB BIT(0) +#define OWL_I2C_FIFOSTAT_RNB BIT(1) +#define OWL_I2C_FIFOSTAT_RFE BIT(2) +#define OWL_I2C_FIFOSTAT_TFF BIT(5) +#define OWL_I2C_FIFOSTAT_TFD GENMASK(23, 16) +#define OWL_I2C_FIFOSTAT_RFD GENMASK(15, 8) + +/* I2C bus timeout */ +#define OWL_I2C_TIMEOUT_MS (4 * 1000) +#define OWL_I2C_TIMEOUT msecs_to_jiffies(OWL_I2C_TIMEOUT_MS) + +#define OWL_I2C_MAX_RETRIES 50 + +struct owl_i2c_dev { + struct i2c_adapter adap; + struct i2c_msg *msg; + struct completion msg_complete; + struct clk *clk; + spinlock_t lock; + void __iomem *base; + unsigned long clk_rate; + u32 bus_freq; + u32 msg_ptr; + int err; +}; + +static void owl_i2c_update_reg(void __iomem *reg, unsigned int val, bool state) +{ + unsigned int regval; + + regval = readl(reg); + + if (state) + regval |= val; + else + regval &= ~val; + + writel(regval, reg); +} + +static void owl_i2c_reset(struct owl_i2c_dev *i2c_dev) +{ + owl_i2c_update_reg(i2c_dev->base + OWL_I2C_REG_CTL, + OWL_I2C_CTL_EN, false); + mdelay(1); + owl_i2c_update_reg(i2c_dev->base + OWL_I2C_REG_CTL, + OWL_I2C_CTL_EN, true); + + /* Clear status registers */ + writel(0, i2c_dev->base + OWL_I2C_REG_STAT); +} + +static int owl_i2c_reset_fifo(struct owl_i2c_dev *i2c_dev) +{ + unsigned int val, timeout = 0; + + /* Reset FIFO */ + owl_i2c_update_reg(i2c_dev->base + OWL_I2C_REG_FIFOCTL, + OWL_I2C_FIFOCTL_RFR | OWL_I2C_FIFOCTL_TFR, + true); + + /* Wait 50ms for FIFO reset complete */ + do { + val = readl(i2c_dev->base + OWL_I2C_REG_FIFOCTL); + if (!(val & (OWL_I2C_FIFOCTL_RFR | OWL_I2C_FIFOCTL_TFR))) + break; + usleep_range(500, 1000); + } while (timeout++ < OWL_I2C_MAX_RETRIES); + + if (timeout > OWL_I2C_MAX_RETRIES) { + dev_err(&i2c_dev->adap.dev, "FIFO reset timeout\n"); + return -ETIMEDOUT; + } + + return 0; +} + +static void owl_i2c_set_freq(struct owl_i2c_dev *i2c_dev) +{ + unsigned int val; + + val = DIV_ROUND_UP(i2c_dev->clk_rate, i2c_dev->bus_freq * 16); + + /* Set clock divider factor */ + writel(OWL_I2C_DIV_FACTOR(val), i2c_dev->base + OWL_I2C_REG_CLKDIV); +} + +static void owl_i2c_xfer_data(struct owl_i2c_dev *i2c_dev) +{ + struct i2c_msg *msg = i2c_dev->msg; + unsigned int stat, fifostat; + + i2c_dev->err = 0; + + /* Handle NACK from slave */ + fifostat = readl(i2c_dev->base + OWL_I2C_REG_FIFOSTAT); + if (fifostat & OWL_I2C_FIFOSTAT_RNB) { + i2c_dev->err = -ENXIO; + /* Clear NACK error bit by writing "1" */ + owl_i2c_update_reg(i2c_dev->base + OWL_I2C_REG_FIFOSTAT, + OWL_I2C_FIFOSTAT_RNB, true); + return; + } + + /* Handle bus error */ + stat = readl(i2c_dev->base + OWL_I2C_REG_STAT); + if (stat & OWL_I2C_STAT_BEB) { + i2c_dev->err = -EIO; + /* Clear BUS error bit by writing "1" */ + owl_i2c_update_reg(i2c_dev->base + OWL_I2C_REG_STAT, + OWL_I2C_STAT_BEB, true); + return; + } + + /* Handle FIFO read */ + if (msg->flags & I2C_M_RD) { + while ((readl(i2c_dev->base + OWL_I2C_REG_FIFOSTAT) & + OWL_I2C_FIFOSTAT_RFE) && i2c_dev->msg_ptr < msg->len) { + msg->buf[i2c_dev->msg_ptr++] = readl(i2c_dev->base + + OWL_I2C_REG_RXDAT); + } + } else { + /* Handle the remaining bytes which were not sent */ + while (!(readl(i2c_dev->base + OWL_I2C_REG_FIFOSTAT) & + OWL_I2C_FIFOSTAT_TFF) && i2c_dev->msg_ptr < msg->len) { + writel(msg->buf[i2c_dev->msg_ptr++], + i2c_dev->base + OWL_I2C_REG_TXDAT); + } + } +} + +static irqreturn_t owl_i2c_interrupt(int irq, void *_dev) +{ + struct owl_i2c_dev *i2c_dev = _dev; + + spin_lock(&i2c_dev->lock); + + owl_i2c_xfer_data(i2c_dev); + + /* Clear pending interrupts */ + owl_i2c_update_reg(i2c_dev->base + OWL_I2C_REG_STAT, + OWL_I2C_STAT_IRQP, true); + + complete_all(&i2c_dev->msg_complete); + spin_unlock(&i2c_dev->lock); + + return IRQ_HANDLED; +} + +static u32 owl_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static int owl_i2c_check_bus_busy(struct i2c_adapter *adap) +{ + struct owl_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + unsigned long timeout; + + /* Check for Bus busy */ + timeout = jiffies + OWL_I2C_TIMEOUT; + while (readl(i2c_dev->base + OWL_I2C_REG_STAT) & OWL_I2C_STAT_BBB) { + if (time_after(jiffies, timeout)) { + dev_err(&adap->dev, "Bus busy timeout\n"); + return -ETIMEDOUT; + } + } + + return 0; +} + +static int owl_i2c_xfer_common(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num, bool atomic) +{ + struct owl_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + struct i2c_msg *msg; + unsigned long time_left, flags; + unsigned int i2c_cmd, val; + unsigned int addr; + int ret, idx; + + spin_lock_irqsave(&i2c_dev->lock, flags); + + /* Reset I2C controller */ + owl_i2c_reset(i2c_dev); + + /* Set bus frequency */ + owl_i2c_set_freq(i2c_dev); + + /* + * Spinlock should be released before calling reset FIFO and + * bus busy check since those functions may sleep + */ + spin_unlock_irqrestore(&i2c_dev->lock, flags); + + /* Reset FIFO */ + ret = owl_i2c_reset_fifo(i2c_dev); + if (ret) + goto unlocked_err_exit; + + /* Check for bus busy */ + ret = owl_i2c_check_bus_busy(adap); + if (ret) + goto unlocked_err_exit; + + spin_lock_irqsave(&i2c_dev->lock, flags); + + /* Check for Arbitration lost */ + val = readl(i2c_dev->base + OWL_I2C_REG_STAT); + if (val & OWL_I2C_STAT_LAB) { + val &= ~OWL_I2C_STAT_LAB; + writel(val, i2c_dev->base + OWL_I2C_REG_STAT); + ret = -EAGAIN; + goto err_exit; + } + + if (!atomic) + reinit_completion(&i2c_dev->msg_complete); + + /* Enable/disable I2C controller interrupt */ + owl_i2c_update_reg(i2c_dev->base + OWL_I2C_REG_CTL, + OWL_I2C_CTL_IRQE, !atomic); + + /* + * Select: FIFO enable, Master mode, Stop enable, Data count enable, + * Send start bit + */ + i2c_cmd = OWL_I2C_CMD_SECL | OWL_I2C_CMD_MSS | OWL_I2C_CMD_SE | + OWL_I2C_CMD_NS | OWL_I2C_CMD_DE | OWL_I2C_CMD_SBE; + + /* Handle repeated start condition */ + if (num > 1) { + /* Set internal address length and enable repeated start */ + i2c_cmd |= OWL_I2C_CMD_AS(msgs[0].len + 1) | + OWL_I2C_CMD_SAS(1) | OWL_I2C_CMD_RBE; + + /* Write slave address */ + addr = i2c_8bit_addr_from_msg(&msgs[0]); + writel(addr, i2c_dev->base + OWL_I2C_REG_TXDAT); + + /* Write internal register address */ + for (idx = 0; idx < msgs[0].len; idx++) + writel(msgs[0].buf[idx], + i2c_dev->base + OWL_I2C_REG_TXDAT); + + msg = &msgs[1]; + } else { + /* Set address length */ + i2c_cmd |= OWL_I2C_CMD_AS(1); + msg = &msgs[0]; + } + + i2c_dev->msg = msg; + i2c_dev->msg_ptr = 0; + + /* Set data count for the message */ + writel(msg->len, i2c_dev->base + OWL_I2C_REG_DATCNT); + + addr = i2c_8bit_addr_from_msg(msg); + writel(addr, i2c_dev->base + OWL_I2C_REG_TXDAT); + + if (!(msg->flags & I2C_M_RD)) { + /* Write data to FIFO */ + for (idx = 0; idx < msg->len; idx++) { + /* Check for FIFO full */ + if (readl(i2c_dev->base + OWL_I2C_REG_FIFOSTAT) & + OWL_I2C_FIFOSTAT_TFF) + break; + + writel(msg->buf[idx], + i2c_dev->base + OWL_I2C_REG_TXDAT); + } + + i2c_dev->msg_ptr = idx; + } + + /* Ignore the NACK if needed */ + if (msg->flags & I2C_M_IGNORE_NAK) + owl_i2c_update_reg(i2c_dev->base + OWL_I2C_REG_FIFOCTL, + OWL_I2C_FIFOCTL_NIB, true); + else + owl_i2c_update_reg(i2c_dev->base + OWL_I2C_REG_FIFOCTL, + OWL_I2C_FIFOCTL_NIB, false); + + /* Start the transfer */ + writel(i2c_cmd, i2c_dev->base + OWL_I2C_REG_CMD); + + spin_unlock_irqrestore(&i2c_dev->lock, flags); + + if (atomic) { + /* Wait for Command Execute Completed or NACK Error bits */ + ret = readl_poll_timeout_atomic(i2c_dev->base + OWL_I2C_REG_FIFOSTAT, + val, val & (OWL_I2C_FIFOSTAT_CECB | + OWL_I2C_FIFOSTAT_RNB), + 10, OWL_I2C_TIMEOUT_MS * 1000); + } else { + time_left = wait_for_completion_timeout(&i2c_dev->msg_complete, + adap->timeout); + if (!time_left) + ret = -ETIMEDOUT; + } + + spin_lock_irqsave(&i2c_dev->lock, flags); + + if (ret) { + dev_err(&adap->dev, "Transaction timed out\n"); + /* Send stop condition and release the bus */ + owl_i2c_update_reg(i2c_dev->base + OWL_I2C_REG_CTL, + OWL_I2C_CTL_GBCC_STOP | OWL_I2C_CTL_RB, + true); + goto err_exit; + } + + if (atomic) + owl_i2c_xfer_data(i2c_dev); + + ret = i2c_dev->err < 0 ? i2c_dev->err : num; + +err_exit: + spin_unlock_irqrestore(&i2c_dev->lock, flags); + +unlocked_err_exit: + /* Disable I2C controller */ + owl_i2c_update_reg(i2c_dev->base + OWL_I2C_REG_CTL, + OWL_I2C_CTL_EN, false); + + return ret; +} + +static int owl_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + return owl_i2c_xfer_common(adap, msgs, num, false); +} + +static int owl_i2c_xfer_atomic(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + return owl_i2c_xfer_common(adap, msgs, num, true); +} + +static const struct i2c_algorithm owl_i2c_algorithm = { + .master_xfer = owl_i2c_xfer, + .master_xfer_atomic = owl_i2c_xfer_atomic, + .functionality = owl_i2c_func, +}; + +static const struct i2c_adapter_quirks owl_i2c_quirks = { + .flags = I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST, + .max_read_len = 240, + .max_write_len = 240, + .max_comb_1st_msg_len = 6, + .max_comb_2nd_msg_len = 240, +}; + +static int owl_i2c_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct owl_i2c_dev *i2c_dev; + int ret, irq; + + i2c_dev = devm_kzalloc(dev, sizeof(*i2c_dev), GFP_KERNEL); + if (!i2c_dev) + return -ENOMEM; + + i2c_dev->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c_dev->base)) + return PTR_ERR(i2c_dev->base); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + if (of_property_read_u32(dev->of_node, "clock-frequency", + &i2c_dev->bus_freq)) + i2c_dev->bus_freq = I2C_MAX_STANDARD_MODE_FREQ; + + /* We support only frequencies of 100k and 400k for now */ + if (i2c_dev->bus_freq != I2C_MAX_STANDARD_MODE_FREQ && + i2c_dev->bus_freq != I2C_MAX_FAST_MODE_FREQ) { + dev_err(dev, "invalid clock-frequency %d\n", i2c_dev->bus_freq); + return -EINVAL; + } + + i2c_dev->clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(i2c_dev->clk)) { + dev_err(dev, "failed to enable clock\n"); + return PTR_ERR(i2c_dev->clk); + } + + i2c_dev->clk_rate = clk_get_rate(i2c_dev->clk); + if (!i2c_dev->clk_rate) { + dev_err(dev, "input clock rate should not be zero\n"); + return -EINVAL; + } + + init_completion(&i2c_dev->msg_complete); + spin_lock_init(&i2c_dev->lock); + i2c_dev->adap.owner = THIS_MODULE; + i2c_dev->adap.algo = &owl_i2c_algorithm; + i2c_dev->adap.timeout = OWL_I2C_TIMEOUT; + i2c_dev->adap.quirks = &owl_i2c_quirks; + i2c_dev->adap.dev.parent = dev; + i2c_dev->adap.dev.of_node = dev->of_node; + snprintf(i2c_dev->adap.name, sizeof(i2c_dev->adap.name), + "%s", "OWL I2C adapter"); + i2c_set_adapdata(&i2c_dev->adap, i2c_dev); + + platform_set_drvdata(pdev, i2c_dev); + + ret = devm_request_irq(dev, irq, owl_i2c_interrupt, 0, pdev->name, + i2c_dev); + if (ret) { + dev_err(dev, "failed to request irq %d\n", irq); + return ret; + } + + return i2c_add_adapter(&i2c_dev->adap); +} + +static const struct of_device_id owl_i2c_of_match[] = { + { .compatible = "actions,s500-i2c" }, + { .compatible = "actions,s700-i2c" }, + { .compatible = "actions,s900-i2c" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, owl_i2c_of_match); + +static struct platform_driver owl_i2c_driver = { + .probe = owl_i2c_probe, + .driver = { + .name = "owl-i2c", + .of_match_table = owl_i2c_of_match, + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + }, +}; +module_platform_driver(owl_i2c_driver); + +MODULE_AUTHOR("David Liu <liuwei@actions-semi.com>"); +MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>"); +MODULE_DESCRIPTION("Actions Semiconductor Owl SoC's I2C driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-parport.c b/drivers/i2c/busses/i2c-parport.c new file mode 100644 index 000000000..0af86a542 --- /dev/null +++ b/drivers/i2c/busses/i2c-parport.c @@ -0,0 +1,409 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* ------------------------------------------------------------------------ * + * i2c-parport.c I2C bus over parallel port * + * ------------------------------------------------------------------------ * + Copyright (C) 2003-2011 Jean Delvare <jdelvare@suse.de> + + Based on older i2c-philips-par.c driver + Copyright (C) 1995-2000 Simon G. Vogl + With some changes from: + Frodo Looijaard <frodol@dds.nl> + Kyösti Mälkki <kmalkki@cc.hut.fi> + + * ------------------------------------------------------------------------ */ + +#define pr_fmt(fmt) "i2c-parport: " fmt + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/parport.h> +#include <linux/i2c.h> +#include <linux/i2c-algo-bit.h> +#include <linux/i2c-smbus.h> +#include <linux/slab.h> +#include <linux/list.h> +#include <linux/mutex.h> + +#define PORT_DATA 0 +#define PORT_STAT 1 +#define PORT_CTRL 2 + +struct lineop { + u8 val; + u8 port; + u8 inverted; +}; + +struct adapter_parm { + struct lineop setsda; + struct lineop setscl; + struct lineop getsda; + struct lineop getscl; + struct lineop init; + unsigned int smbus_alert:1; +}; + +static const struct adapter_parm adapter_parm[] = { + /* type 0: Philips adapter */ + { + .setsda = { 0x80, PORT_DATA, 1 }, + .setscl = { 0x08, PORT_CTRL, 0 }, + .getsda = { 0x80, PORT_STAT, 0 }, + .getscl = { 0x08, PORT_STAT, 0 }, + }, + /* type 1: home brew teletext adapter */ + { + .setsda = { 0x02, PORT_DATA, 0 }, + .setscl = { 0x01, PORT_DATA, 0 }, + .getsda = { 0x80, PORT_STAT, 1 }, + }, + /* type 2: Velleman K8000 adapter */ + { + .setsda = { 0x02, PORT_CTRL, 1 }, + .setscl = { 0x08, PORT_CTRL, 1 }, + .getsda = { 0x10, PORT_STAT, 0 }, + }, + /* type 3: ELV adapter */ + { + .setsda = { 0x02, PORT_DATA, 1 }, + .setscl = { 0x01, PORT_DATA, 1 }, + .getsda = { 0x40, PORT_STAT, 1 }, + .getscl = { 0x08, PORT_STAT, 1 }, + }, + /* type 4: ADM1032 evaluation board */ + { + .setsda = { 0x02, PORT_DATA, 1 }, + .setscl = { 0x01, PORT_DATA, 1 }, + .getsda = { 0x10, PORT_STAT, 1 }, + .init = { 0xf0, PORT_DATA, 0 }, + .smbus_alert = 1, + }, + /* type 5: ADM1025, ADM1030 and ADM1031 evaluation boards */ + { + .setsda = { 0x02, PORT_DATA, 1 }, + .setscl = { 0x01, PORT_DATA, 1 }, + .getsda = { 0x10, PORT_STAT, 1 }, + }, + /* type 6: Barco LPT->DVI (K5800236) adapter */ + { + .setsda = { 0x02, PORT_DATA, 1 }, + .setscl = { 0x01, PORT_DATA, 1 }, + .getsda = { 0x20, PORT_STAT, 0 }, + .getscl = { 0x40, PORT_STAT, 0 }, + .init = { 0xfc, PORT_DATA, 0 }, + }, + /* type 7: One For All JP1 parallel port adapter */ + { + .setsda = { 0x01, PORT_DATA, 0 }, + .setscl = { 0x02, PORT_DATA, 0 }, + .getsda = { 0x80, PORT_STAT, 1 }, + .init = { 0x04, PORT_DATA, 1 }, + }, + /* type 8: VCT-jig */ + { + .setsda = { 0x04, PORT_DATA, 1 }, + .setscl = { 0x01, PORT_DATA, 1 }, + .getsda = { 0x40, PORT_STAT, 0 }, + .getscl = { 0x80, PORT_STAT, 1 }, + }, +}; + +/* ----- Device list ------------------------------------------------------ */ + +struct i2c_par { + struct pardevice *pdev; + struct i2c_adapter adapter; + struct i2c_algo_bit_data algo_data; + struct i2c_smbus_alert_setup alert_data; + struct i2c_client *ara; + struct list_head node; +}; + +static LIST_HEAD(adapter_list); +static DEFINE_MUTEX(adapter_list_lock); + +#define MAX_DEVICE 4 +static int parport[MAX_DEVICE] = {0, -1, -1, -1}; +module_param_array(parport, int, NULL, 0); +MODULE_PARM_DESC(parport, + "List of parallel ports to bind to, by index.\n" + " At most " __stringify(MAX_DEVICE) " devices are supported.\n" + " Default is one device connected to parport0.\n" +); + +static int type = -1; +module_param(type, int, 0); +MODULE_PARM_DESC(type, + "Type of adapter:\n" + " 0 = Philips adapter\n" + " 1 = home brew teletext adapter\n" + " 2 = Velleman K8000 adapter\n" + " 3 = ELV adapter\n" + " 4 = ADM1032 evaluation board\n" + " 5 = ADM1025, ADM1030 and ADM1031 evaluation boards\n" + " 6 = Barco LPT->DVI (K5800236) adapter\n" + " 7 = One For All JP1 parallel port adapter\n" + " 8 = VCT-jig\n" +); + +/* ----- Low-level parallel port access ----------------------------------- */ + +static void port_write_data(struct parport *p, unsigned char d) +{ + parport_write_data(p, d); +} + +static void port_write_control(struct parport *p, unsigned char d) +{ + parport_write_control(p, d); +} + +static unsigned char port_read_data(struct parport *p) +{ + return parport_read_data(p); +} + +static unsigned char port_read_status(struct parport *p) +{ + return parport_read_status(p); +} + +static unsigned char port_read_control(struct parport *p) +{ + return parport_read_control(p); +} + +static void (* const port_write[])(struct parport *, unsigned char) = { + port_write_data, + NULL, + port_write_control, +}; + +static unsigned char (* const port_read[])(struct parport *) = { + port_read_data, + port_read_status, + port_read_control, +}; + +/* ----- Unified line operation functions --------------------------------- */ + +static inline void line_set(struct parport *data, int state, + const struct lineop *op) +{ + u8 oldval = port_read[op->port](data); + + /* Touch only the bit(s) needed */ + if ((op->inverted && !state) || (!op->inverted && state)) + port_write[op->port](data, oldval | op->val); + else + port_write[op->port](data, oldval & ~op->val); +} + +static inline int line_get(struct parport *data, + const struct lineop *op) +{ + u8 oldval = port_read[op->port](data); + + return ((op->inverted && (oldval & op->val) != op->val) + || (!op->inverted && (oldval & op->val) == op->val)); +} + +/* ----- I2C algorithm call-back functions and structures ----------------- */ + +static void parport_setscl(void *data, int state) +{ + line_set((struct parport *) data, state, &adapter_parm[type].setscl); +} + +static void parport_setsda(void *data, int state) +{ + line_set((struct parport *) data, state, &adapter_parm[type].setsda); +} + +static int parport_getscl(void *data) +{ + return line_get((struct parport *) data, &adapter_parm[type].getscl); +} + +static int parport_getsda(void *data) +{ + return line_get((struct parport *) data, &adapter_parm[type].getsda); +} + +/* Encapsulate the functions above in the correct structure. + Note that this is only a template, from which the real structures are + copied. The attaching code will set getscl to NULL for adapters that + cannot read SCL back, and will also make the data field point to + the parallel port structure. */ +static const struct i2c_algo_bit_data parport_algo_data = { + .setsda = parport_setsda, + .setscl = parport_setscl, + .getsda = parport_getsda, + .getscl = parport_getscl, + .udelay = 10, /* ~50 kbps */ + .timeout = HZ, +}; + +/* ----- I2c and parallel port call-back functions and structures --------- */ + +static void i2c_parport_irq(void *data) +{ + struct i2c_par *adapter = data; + struct i2c_client *ara = adapter->ara; + + if (ara) { + dev_dbg(&ara->dev, "SMBus alert received\n"); + i2c_handle_smbus_alert(ara); + } else + dev_dbg(&adapter->adapter.dev, + "SMBus alert received but no ARA client!\n"); +} + +static void i2c_parport_attach(struct parport *port) +{ + struct i2c_par *adapter; + int i; + struct pardev_cb i2c_parport_cb; + + if (type < 0) { + pr_warn("adapter type unspecified\n"); + return; + } + + if (type >= ARRAY_SIZE(adapter_parm)) { + pr_warn("invalid type (%d)\n", type); + return; + } + + for (i = 0; i < MAX_DEVICE; i++) { + if (parport[i] == -1) + continue; + if (port->number == parport[i]) + break; + } + if (i == MAX_DEVICE) { + pr_debug("Not using parport%d.\n", port->number); + return; + } + + adapter = kzalloc(sizeof(struct i2c_par), GFP_KERNEL); + if (!adapter) + return; + memset(&i2c_parport_cb, 0, sizeof(i2c_parport_cb)); + i2c_parport_cb.flags = PARPORT_FLAG_EXCL; + i2c_parport_cb.irq_func = i2c_parport_irq; + i2c_parport_cb.private = adapter; + + pr_debug("attaching to %s\n", port->name); + parport_disable_irq(port); + adapter->pdev = parport_register_dev_model(port, "i2c-parport", + &i2c_parport_cb, i); + if (!adapter->pdev) { + pr_err("Unable to register with parport\n"); + goto err_free; + } + + /* Fill the rest of the structure */ + adapter->adapter.owner = THIS_MODULE; + adapter->adapter.class = I2C_CLASS_HWMON; + strscpy(adapter->adapter.name, "Parallel port adapter", + sizeof(adapter->adapter.name)); + adapter->algo_data = parport_algo_data; + /* Slow down if we can't sense SCL */ + if (!adapter_parm[type].getscl.val) { + adapter->algo_data.getscl = NULL; + adapter->algo_data.udelay = 50; /* ~10 kbps */ + } + adapter->algo_data.data = port; + adapter->adapter.algo_data = &adapter->algo_data; + adapter->adapter.dev.parent = port->physport->dev; + + if (parport_claim_or_block(adapter->pdev) < 0) { + dev_err(&adapter->pdev->dev, + "Could not claim parallel port\n"); + goto err_unregister; + } + + /* Reset hardware to a sane state (SCL and SDA high) */ + parport_setsda(port, 1); + parport_setscl(port, 1); + /* Other init if needed (power on...) */ + if (adapter_parm[type].init.val) { + line_set(port, 1, &adapter_parm[type].init); + /* Give powered devices some time to settle */ + msleep(100); + } + + if (i2c_bit_add_bus(&adapter->adapter) < 0) { + dev_err(&adapter->pdev->dev, "Unable to register with I2C\n"); + goto err_unregister; + } + + /* Setup SMBus alert if supported */ + if (adapter_parm[type].smbus_alert) { + struct i2c_client *ara; + + ara = i2c_new_smbus_alert_device(&adapter->adapter, + &adapter->alert_data); + if (!IS_ERR(ara)) { + adapter->ara = ara; + parport_enable_irq(port); + } else { + dev_warn(&adapter->pdev->dev, + "Failed to register ARA client\n"); + } + } + + /* Add the new adapter to the list */ + mutex_lock(&adapter_list_lock); + list_add_tail(&adapter->node, &adapter_list); + mutex_unlock(&adapter_list_lock); + return; + + err_unregister: + parport_release(adapter->pdev); + parport_unregister_device(adapter->pdev); + err_free: + kfree(adapter); +} + +static void i2c_parport_detach(struct parport *port) +{ + struct i2c_par *adapter, *_n; + + /* Walk the list */ + mutex_lock(&adapter_list_lock); + list_for_each_entry_safe(adapter, _n, &adapter_list, node) { + if (adapter->pdev->port == port) { + if (adapter->ara) { + parport_disable_irq(port); + i2c_unregister_device(adapter->ara); + } + i2c_del_adapter(&adapter->adapter); + + /* Un-init if needed (power off...) */ + if (adapter_parm[type].init.val) + line_set(port, 0, &adapter_parm[type].init); + + parport_release(adapter->pdev); + parport_unregister_device(adapter->pdev); + list_del(&adapter->node); + kfree(adapter); + } + } + mutex_unlock(&adapter_list_lock); +} + +static struct parport_driver i2c_parport_driver = { + .name = "i2c-parport", + .match_port = i2c_parport_attach, + .detach = i2c_parport_detach, + .devmodel = true, +}; +module_parport_driver(i2c_parport_driver); + +MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>"); +MODULE_DESCRIPTION("I2C bus over parallel port"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-pasemi-core.c b/drivers/i2c/busses/i2c-pasemi-core.c new file mode 100644 index 000000000..7d54a9f34 --- /dev/null +++ b/drivers/i2c/busses/i2c-pasemi-core.c @@ -0,0 +1,380 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2006-2007 PA Semi, Inc + * + * SMBus host driver for PA Semi PWRficient + */ + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/stddef.h> +#include <linux/sched.h> +#include <linux/i2c.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/io.h> + +#include "i2c-pasemi-core.h" + +/* Register offsets */ +#define REG_MTXFIFO 0x00 +#define REG_MRXFIFO 0x04 +#define REG_SMSTA 0x14 +#define REG_IMASK 0x18 +#define REG_CTL 0x1c +#define REG_REV 0x28 + +/* Register defs */ +#define MTXFIFO_READ 0x00000400 +#define MTXFIFO_STOP 0x00000200 +#define MTXFIFO_START 0x00000100 +#define MTXFIFO_DATA_M 0x000000ff + +#define MRXFIFO_EMPTY 0x00000100 +#define MRXFIFO_DATA_M 0x000000ff + +#define SMSTA_XEN 0x08000000 +#define SMSTA_MTN 0x00200000 + +#define CTL_MRR 0x00000400 +#define CTL_MTR 0x00000200 +#define CTL_EN 0x00000800 +#define CTL_CLK_M 0x000000ff + +static inline void reg_write(struct pasemi_smbus *smbus, int reg, int val) +{ + dev_dbg(smbus->dev, "smbus write reg %x val %08x\n", reg, val); + iowrite32(val, smbus->ioaddr + reg); +} + +static inline int reg_read(struct pasemi_smbus *smbus, int reg) +{ + int ret; + ret = ioread32(smbus->ioaddr + reg); + dev_dbg(smbus->dev, "smbus read reg %x val %08x\n", reg, ret); + return ret; +} + +#define TXFIFO_WR(smbus, reg) reg_write((smbus), REG_MTXFIFO, (reg)) +#define RXFIFO_RD(smbus) reg_read((smbus), REG_MRXFIFO) + +static void pasemi_reset(struct pasemi_smbus *smbus) +{ + u32 val = (CTL_MTR | CTL_MRR | (smbus->clk_div & CTL_CLK_M)); + + if (smbus->hw_rev >= 6) + val |= CTL_EN; + + reg_write(smbus, REG_CTL, val); + reinit_completion(&smbus->irq_completion); +} + +static void pasemi_smb_clear(struct pasemi_smbus *smbus) +{ + unsigned int status; + + status = reg_read(smbus, REG_SMSTA); + reg_write(smbus, REG_SMSTA, status); +} + +static int pasemi_smb_waitready(struct pasemi_smbus *smbus) +{ + int timeout = 100; + unsigned int status; + + if (smbus->use_irq) { + reinit_completion(&smbus->irq_completion); + reg_write(smbus, REG_IMASK, SMSTA_XEN | SMSTA_MTN); + wait_for_completion_timeout(&smbus->irq_completion, msecs_to_jiffies(100)); + reg_write(smbus, REG_IMASK, 0); + status = reg_read(smbus, REG_SMSTA); + } else { + status = reg_read(smbus, REG_SMSTA); + while (!(status & SMSTA_XEN) && timeout--) { + msleep(1); + status = reg_read(smbus, REG_SMSTA); + } + } + + /* Got NACK? */ + if (status & SMSTA_MTN) + return -ENXIO; + + if (timeout < 0) { + dev_warn(smbus->dev, "Timeout, status 0x%08x\n", status); + reg_write(smbus, REG_SMSTA, status); + return -ETIME; + } + + /* Clear XEN */ + reg_write(smbus, REG_SMSTA, SMSTA_XEN); + + return 0; +} + +static int pasemi_i2c_xfer_msg(struct i2c_adapter *adapter, + struct i2c_msg *msg, int stop) +{ + struct pasemi_smbus *smbus = adapter->algo_data; + int read, i, err; + u32 rd; + + read = msg->flags & I2C_M_RD ? 1 : 0; + + TXFIFO_WR(smbus, MTXFIFO_START | i2c_8bit_addr_from_msg(msg)); + + if (read) { + TXFIFO_WR(smbus, msg->len | MTXFIFO_READ | + (stop ? MTXFIFO_STOP : 0)); + + err = pasemi_smb_waitready(smbus); + if (err) + goto reset_out; + + for (i = 0; i < msg->len; i++) { + rd = RXFIFO_RD(smbus); + if (rd & MRXFIFO_EMPTY) { + err = -ENODATA; + goto reset_out; + } + msg->buf[i] = rd & MRXFIFO_DATA_M; + } + } else { + for (i = 0; i < msg->len - 1; i++) + TXFIFO_WR(smbus, msg->buf[i]); + + TXFIFO_WR(smbus, msg->buf[msg->len-1] | + (stop ? MTXFIFO_STOP : 0)); + + if (stop) { + err = pasemi_smb_waitready(smbus); + if (err) + goto reset_out; + } + } + + return 0; + + reset_out: + pasemi_reset(smbus); + return err; +} + +static int pasemi_i2c_xfer(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num) +{ + struct pasemi_smbus *smbus = adapter->algo_data; + int ret, i; + + pasemi_smb_clear(smbus); + + ret = 0; + + for (i = 0; i < num && !ret; i++) + ret = pasemi_i2c_xfer_msg(adapter, &msgs[i], (i == (num - 1))); + + return ret ? ret : num; +} + +static int pasemi_smb_xfer(struct i2c_adapter *adapter, + u16 addr, unsigned short flags, char read_write, u8 command, + int size, union i2c_smbus_data *data) +{ + struct pasemi_smbus *smbus = adapter->algo_data; + unsigned int rd; + int read_flag, err; + int len = 0, i; + + /* All our ops take 8-bit shifted addresses */ + addr <<= 1; + read_flag = read_write == I2C_SMBUS_READ; + + pasemi_smb_clear(smbus); + + switch (size) { + case I2C_SMBUS_QUICK: + TXFIFO_WR(smbus, addr | read_flag | MTXFIFO_START | + MTXFIFO_STOP); + break; + case I2C_SMBUS_BYTE: + TXFIFO_WR(smbus, addr | read_flag | MTXFIFO_START); + if (read_write) + TXFIFO_WR(smbus, 1 | MTXFIFO_STOP | MTXFIFO_READ); + else + TXFIFO_WR(smbus, MTXFIFO_STOP | command); + break; + case I2C_SMBUS_BYTE_DATA: + TXFIFO_WR(smbus, addr | MTXFIFO_START); + TXFIFO_WR(smbus, command); + if (read_write) { + TXFIFO_WR(smbus, addr | I2C_SMBUS_READ | MTXFIFO_START); + TXFIFO_WR(smbus, 1 | MTXFIFO_READ | MTXFIFO_STOP); + } else { + TXFIFO_WR(smbus, MTXFIFO_STOP | data->byte); + } + break; + case I2C_SMBUS_WORD_DATA: + TXFIFO_WR(smbus, addr | MTXFIFO_START); + TXFIFO_WR(smbus, command); + if (read_write) { + TXFIFO_WR(smbus, addr | I2C_SMBUS_READ | MTXFIFO_START); + TXFIFO_WR(smbus, 2 | MTXFIFO_READ | MTXFIFO_STOP); + } else { + TXFIFO_WR(smbus, data->word & MTXFIFO_DATA_M); + TXFIFO_WR(smbus, MTXFIFO_STOP | (data->word >> 8)); + } + break; + case I2C_SMBUS_BLOCK_DATA: + TXFIFO_WR(smbus, addr | MTXFIFO_START); + TXFIFO_WR(smbus, command); + if (read_write) { + TXFIFO_WR(smbus, addr | I2C_SMBUS_READ | MTXFIFO_START); + TXFIFO_WR(smbus, 1 | MTXFIFO_READ); + rd = RXFIFO_RD(smbus); + len = min_t(u8, (rd & MRXFIFO_DATA_M), + I2C_SMBUS_BLOCK_MAX); + TXFIFO_WR(smbus, len | MTXFIFO_READ | + MTXFIFO_STOP); + } else { + len = min_t(u8, data->block[0], I2C_SMBUS_BLOCK_MAX); + TXFIFO_WR(smbus, len); + for (i = 1; i < len; i++) + TXFIFO_WR(smbus, data->block[i]); + TXFIFO_WR(smbus, data->block[len] | MTXFIFO_STOP); + } + break; + case I2C_SMBUS_PROC_CALL: + read_write = I2C_SMBUS_READ; + TXFIFO_WR(smbus, addr | MTXFIFO_START); + TXFIFO_WR(smbus, command); + TXFIFO_WR(smbus, data->word & MTXFIFO_DATA_M); + TXFIFO_WR(smbus, (data->word >> 8) & MTXFIFO_DATA_M); + TXFIFO_WR(smbus, addr | I2C_SMBUS_READ | MTXFIFO_START); + TXFIFO_WR(smbus, 2 | MTXFIFO_STOP | MTXFIFO_READ); + break; + case I2C_SMBUS_BLOCK_PROC_CALL: + len = min_t(u8, data->block[0], I2C_SMBUS_BLOCK_MAX - 1); + read_write = I2C_SMBUS_READ; + TXFIFO_WR(smbus, addr | MTXFIFO_START); + TXFIFO_WR(smbus, command); + TXFIFO_WR(smbus, len); + for (i = 1; i <= len; i++) + TXFIFO_WR(smbus, data->block[i]); + TXFIFO_WR(smbus, addr | I2C_SMBUS_READ); + TXFIFO_WR(smbus, MTXFIFO_READ | 1); + rd = RXFIFO_RD(smbus); + len = min_t(u8, (rd & MRXFIFO_DATA_M), + I2C_SMBUS_BLOCK_MAX - len); + TXFIFO_WR(smbus, len | MTXFIFO_READ | MTXFIFO_STOP); + break; + + default: + dev_warn(&adapter->dev, "Unsupported transaction %d\n", size); + return -EINVAL; + } + + err = pasemi_smb_waitready(smbus); + if (err) + goto reset_out; + + if (read_write == I2C_SMBUS_WRITE) + return 0; + + switch (size) { + case I2C_SMBUS_BYTE: + case I2C_SMBUS_BYTE_DATA: + rd = RXFIFO_RD(smbus); + if (rd & MRXFIFO_EMPTY) { + err = -ENODATA; + goto reset_out; + } + data->byte = rd & MRXFIFO_DATA_M; + break; + case I2C_SMBUS_WORD_DATA: + case I2C_SMBUS_PROC_CALL: + rd = RXFIFO_RD(smbus); + if (rd & MRXFIFO_EMPTY) { + err = -ENODATA; + goto reset_out; + } + data->word = rd & MRXFIFO_DATA_M; + rd = RXFIFO_RD(smbus); + if (rd & MRXFIFO_EMPTY) { + err = -ENODATA; + goto reset_out; + } + data->word |= (rd & MRXFIFO_DATA_M) << 8; + break; + case I2C_SMBUS_BLOCK_DATA: + case I2C_SMBUS_BLOCK_PROC_CALL: + data->block[0] = len; + for (i = 1; i <= len; i ++) { + rd = RXFIFO_RD(smbus); + if (rd & MRXFIFO_EMPTY) { + err = -ENODATA; + goto reset_out; + } + data->block[i] = rd & MRXFIFO_DATA_M; + } + break; + } + + return 0; + + reset_out: + pasemi_reset(smbus); + return err; +} + +static u32 pasemi_smb_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_PROC_CALL | + I2C_FUNC_SMBUS_BLOCK_PROC_CALL | I2C_FUNC_I2C; +} + +static const struct i2c_algorithm smbus_algorithm = { + .master_xfer = pasemi_i2c_xfer, + .smbus_xfer = pasemi_smb_xfer, + .functionality = pasemi_smb_func, +}; + +int pasemi_i2c_common_probe(struct pasemi_smbus *smbus) +{ + int error; + + smbus->adapter.owner = THIS_MODULE; + snprintf(smbus->adapter.name, sizeof(smbus->adapter.name), + "PA Semi SMBus adapter (%s)", dev_name(smbus->dev)); + smbus->adapter.algo = &smbus_algorithm; + smbus->adapter.algo_data = smbus; + + /* set up the sysfs linkage to our parent device */ + smbus->adapter.dev.parent = smbus->dev; + smbus->use_irq = 0; + init_completion(&smbus->irq_completion); + + if (smbus->hw_rev != PASEMI_HW_REV_PCI) + smbus->hw_rev = reg_read(smbus, REG_REV); + + reg_write(smbus, REG_IMASK, 0); + + pasemi_reset(smbus); + + error = devm_i2c_add_adapter(smbus->dev, &smbus->adapter); + if (error) + return error; + + return 0; +} + +irqreturn_t pasemi_irq_handler(int irq, void *dev_id) +{ + struct pasemi_smbus *smbus = dev_id; + + reg_write(smbus, REG_IMASK, 0); + complete(&smbus->irq_completion); + return IRQ_HANDLED; +} diff --git a/drivers/i2c/busses/i2c-pasemi-core.h b/drivers/i2c/busses/i2c-pasemi-core.h new file mode 100644 index 000000000..88821f4e8 --- /dev/null +++ b/drivers/i2c/busses/i2c-pasemi-core.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include <linux/atomic.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/i2c.h> +#include <linux/i2c-smbus.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/completion.h> + +#define PASEMI_HW_REV_PCI -1 + +struct pasemi_smbus { + struct device *dev; + struct i2c_adapter adapter; + void __iomem *ioaddr; + unsigned int clk_div; + int hw_rev; + int use_irq; + struct completion irq_completion; +}; + +int pasemi_i2c_common_probe(struct pasemi_smbus *smbus); + +irqreturn_t pasemi_irq_handler(int irq, void *dev_id); diff --git a/drivers/i2c/busses/i2c-pasemi-pci.c b/drivers/i2c/busses/i2c-pasemi-pci.c new file mode 100644 index 000000000..cfc89e04e --- /dev/null +++ b/drivers/i2c/busses/i2c-pasemi-pci.c @@ -0,0 +1,86 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2006-2007 PA Semi, Inc + * + * SMBus host driver for PA Semi PWRficient + */ + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/stddef.h> +#include <linux/sched.h> +#include <linux/i2c.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/io.h> + +#include "i2c-pasemi-core.h" + +#define CLK_100K_DIV 84 +#define CLK_400K_DIV 21 + +static struct pci_driver pasemi_smb_pci_driver; + +static int pasemi_smb_pci_probe(struct pci_dev *dev, + const struct pci_device_id *id) +{ + struct pasemi_smbus *smbus; + unsigned long base; + int size; + int error; + + if (!(pci_resource_flags(dev, 0) & IORESOURCE_IO)) + return -ENODEV; + + smbus = devm_kzalloc(&dev->dev, sizeof(*smbus), GFP_KERNEL); + if (!smbus) + return -ENOMEM; + + smbus->dev = &dev->dev; + base = pci_resource_start(dev, 0); + size = pci_resource_len(dev, 0); + smbus->clk_div = CLK_100K_DIV; + + /* + * The original PASemi PCI controllers don't have a register for + * their HW revision. + */ + smbus->hw_rev = PASEMI_HW_REV_PCI; + + if (!devm_request_region(&dev->dev, base, size, + pasemi_smb_pci_driver.name)) + return -EBUSY; + + smbus->ioaddr = pcim_iomap(dev, 0, 0); + if (!smbus->ioaddr) + return -EBUSY; + + smbus->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + error = pasemi_i2c_common_probe(smbus); + if (error) + return error; + + pci_set_drvdata(dev, smbus); + + return 0; +} + +static const struct pci_device_id pasemi_smb_pci_ids[] = { + { PCI_DEVICE(0x1959, 0xa003) }, + { 0, } +}; + +MODULE_DEVICE_TABLE(pci, pasemi_smb_pci_ids); + +static struct pci_driver pasemi_smb_pci_driver = { + .name = "i2c-pasemi", + .id_table = pasemi_smb_pci_ids, + .probe = pasemi_smb_pci_probe, +}; + +module_pci_driver(pasemi_smb_pci_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Olof Johansson <olof@lixom.net>"); +MODULE_DESCRIPTION("PA Semi PWRficient SMBus driver"); diff --git a/drivers/i2c/busses/i2c-pasemi-platform.c b/drivers/i2c/busses/i2c-pasemi-platform.c new file mode 100644 index 000000000..5fbfb9b41 --- /dev/null +++ b/drivers/i2c/busses/i2c-pasemi-platform.c @@ -0,0 +1,113 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2021 The Asahi Linux Contributors + * + * PA Semi PWRficient SMBus host driver for Apple SoCs + */ + +#include <linux/clk.h> +#include <linux/i2c.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/types.h> + +#include "i2c-pasemi-core.h" + +struct pasemi_platform_i2c_data { + struct pasemi_smbus smbus; + struct clk *clk_ref; +}; + +static int +pasemi_platform_i2c_calc_clk_div(struct pasemi_platform_i2c_data *data, + u32 frequency) +{ + unsigned long clk_rate = clk_get_rate(data->clk_ref); + + if (!clk_rate) + return -EINVAL; + + data->smbus.clk_div = DIV_ROUND_UP(clk_rate, 16 * frequency); + if (data->smbus.clk_div < 4) + return dev_err_probe(data->smbus.dev, -EINVAL, + "Bus frequency %d is too fast.\n", + frequency); + if (data->smbus.clk_div > 0xff) + return dev_err_probe(data->smbus.dev, -EINVAL, + "Bus frequency %d is too slow.\n", + frequency); + + return 0; +} + +static int pasemi_platform_i2c_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct pasemi_platform_i2c_data *data; + struct pasemi_smbus *smbus; + u32 frequency; + int error; + int irq_num; + + data = devm_kzalloc(dev, sizeof(struct pasemi_platform_i2c_data), + GFP_KERNEL); + if (!data) + return -ENOMEM; + + smbus = &data->smbus; + smbus->dev = dev; + + smbus->ioaddr = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(smbus->ioaddr)) + return PTR_ERR(smbus->ioaddr); + + if (of_property_read_u32(dev->of_node, "clock-frequency", &frequency)) + frequency = I2C_MAX_STANDARD_MODE_FREQ; + + data->clk_ref = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(data->clk_ref)) + return PTR_ERR(data->clk_ref); + + error = pasemi_platform_i2c_calc_clk_div(data, frequency); + if (error) + return error; + + smbus->adapter.dev.of_node = pdev->dev.of_node; + error = pasemi_i2c_common_probe(smbus); + if (error) + return error; + + irq_num = platform_get_irq(pdev, 0); + error = devm_request_irq(smbus->dev, irq_num, pasemi_irq_handler, 0, "pasemi_apple_i2c", (void *)smbus); + + if (!error) + smbus->use_irq = 1; + platform_set_drvdata(pdev, data); + + return 0; +} + +static void pasemi_platform_i2c_remove(struct platform_device *pdev) { } + +static const struct of_device_id pasemi_platform_i2c_of_match[] = { + { .compatible = "apple,t8103-i2c" }, + { .compatible = "apple,i2c" }, + {}, +}; +MODULE_DEVICE_TABLE(of, pasemi_platform_i2c_of_match); + +static struct platform_driver pasemi_platform_i2c_driver = { + .driver = { + .name = "i2c-apple", + .of_match_table = pasemi_platform_i2c_of_match, + }, + .probe = pasemi_platform_i2c_probe, + .remove_new = pasemi_platform_i2c_remove, +}; +module_platform_driver(pasemi_platform_i2c_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Sven Peter <sven@svenpeter.dev>"); +MODULE_DESCRIPTION("Apple/PASemi SMBus platform driver"); diff --git a/drivers/i2c/busses/i2c-pca-isa.c b/drivers/i2c/busses/i2c-pca-isa.c new file mode 100644 index 000000000..85e8cf58e --- /dev/null +++ b/drivers/i2c/busses/i2c-pca-isa.c @@ -0,0 +1,201 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * i2c-pca-isa.c driver for PCA9564 on ISA boards + * Copyright (C) 2004 Arcom Control Systems + * Copyright (C) 2008 Pengutronix + */ + +#include <linux/kernel.h> +#include <linux/ioport.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/delay.h> +#include <linux/jiffies.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/wait.h> +#include <linux/isa.h> +#include <linux/i2c.h> +#include <linux/i2c-algo-pca.h> +#include <linux/io.h> + +#include <asm/irq.h> + +#define DRIVER "i2c-pca-isa" +#define IO_SIZE 4 + +static unsigned long base; +static int irq = -1; + +/* Data sheet recommends 59kHz for 100kHz operation due to variation + * in the actual clock rate */ +static int clock = 59000; + +static struct i2c_adapter pca_isa_ops; +static wait_queue_head_t pca_wait; + +static void pca_isa_writebyte(void *pd, int reg, int val) +{ +#ifdef DEBUG_IO + static char *names[] = { "T/O", "DAT", "ADR", "CON" }; + printk(KERN_DEBUG "*** write %s at %#lx <= %#04x\n", names[reg], + base+reg, val); +#endif + outb(val, base+reg); +} + +static int pca_isa_readbyte(void *pd, int reg) +{ + int res = inb(base+reg); +#ifdef DEBUG_IO + { + static char *names[] = { "STA", "DAT", "ADR", "CON" }; + printk(KERN_DEBUG "*** read %s => %#04x\n", names[reg], res); + } +#endif + return res; +} + +static int pca_isa_waitforcompletion(void *pd) +{ + unsigned long timeout; + long ret; + + if (irq > -1) { + ret = wait_event_timeout(pca_wait, + pca_isa_readbyte(pd, I2C_PCA_CON) + & I2C_PCA_CON_SI, pca_isa_ops.timeout); + } else { + /* Do polling */ + timeout = jiffies + pca_isa_ops.timeout; + do { + ret = time_before(jiffies, timeout); + if (pca_isa_readbyte(pd, I2C_PCA_CON) + & I2C_PCA_CON_SI) + break; + udelay(100); + } while (ret); + } + + return ret > 0; +} + +static void pca_isa_resetchip(void *pd) +{ + /* apparently only an external reset will do it. not a lot can be done */ + printk(KERN_WARNING DRIVER ": Haven't figured out how to do a reset yet\n"); +} + +static irqreturn_t pca_handler(int this_irq, void *dev_id) { + wake_up(&pca_wait); + return IRQ_HANDLED; +} + +static struct i2c_algo_pca_data pca_isa_data = { + /* .data intentionally left NULL, not needed with ISA */ + .write_byte = pca_isa_writebyte, + .read_byte = pca_isa_readbyte, + .wait_for_completion = pca_isa_waitforcompletion, + .reset_chip = pca_isa_resetchip, +}; + +static struct i2c_adapter pca_isa_ops = { + .owner = THIS_MODULE, + .algo_data = &pca_isa_data, + .name = "PCA9564/PCA9665 ISA Adapter", + .timeout = HZ, +}; + +static int pca_isa_match(struct device *dev, unsigned int id) +{ + int match = base != 0; + + if (match) { + if (irq <= -1) + dev_warn(dev, "Using polling mode (specify irq)\n"); + } else + dev_err(dev, "Please specify I/O base\n"); + + return match; +} + +static int pca_isa_probe(struct device *dev, unsigned int id) +{ + init_waitqueue_head(&pca_wait); + + dev_info(dev, "i/o base %#08lx. irq %d\n", base, irq); + +#ifdef CONFIG_PPC + if (check_legacy_ioport(base)) { + dev_err(dev, "I/O address %#08lx is not available\n", base); + goto out; + } +#endif + + if (!request_region(base, IO_SIZE, "i2c-pca-isa")) { + dev_err(dev, "I/O address %#08lx is in use\n", base); + goto out; + } + + if (irq > -1) { + if (request_irq(irq, pca_handler, 0, "i2c-pca-isa", &pca_isa_ops) < 0) { + dev_err(dev, "Request irq%d failed\n", irq); + goto out_region; + } + } + + pca_isa_data.i2c_clock = clock; + if (i2c_pca_add_bus(&pca_isa_ops) < 0) { + dev_err(dev, "Failed to add i2c bus\n"); + goto out_irq; + } + + return 0; + + out_irq: + if (irq > -1) + free_irq(irq, &pca_isa_ops); + out_region: + release_region(base, IO_SIZE); + out: + return -ENODEV; +} + +static void pca_isa_remove(struct device *dev, unsigned int id) +{ + i2c_del_adapter(&pca_isa_ops); + + if (irq > -1) { + disable_irq(irq); + free_irq(irq, &pca_isa_ops); + } + release_region(base, IO_SIZE); +} + +static struct isa_driver pca_isa_driver = { + .match = pca_isa_match, + .probe = pca_isa_probe, + .remove = pca_isa_remove, + .driver = { + .owner = THIS_MODULE, + .name = DRIVER, + } +}; + +MODULE_AUTHOR("Ian Campbell <icampbell@arcom.com>"); +MODULE_DESCRIPTION("ISA base PCA9564/PCA9665 driver"); +MODULE_LICENSE("GPL"); + +module_param_hw(base, ulong, ioport, 0); +MODULE_PARM_DESC(base, "I/O base address"); +module_param_hw(irq, int, irq, 0); +MODULE_PARM_DESC(irq, "IRQ"); +module_param(clock, int, 0); +MODULE_PARM_DESC(clock, "Clock rate in hertz.\n\t\t" + "For PCA9564: 330000,288000,217000,146000," + "88000,59000,44000,36000\n" + "\t\tFor PCA9665:\tStandard: 60300 - 100099\n" + "\t\t\t\tFast: 100100 - 400099\n" + "\t\t\t\tFast+: 400100 - 10000099\n" + "\t\t\t\tTurbo: Up to 1265800"); +module_isa_driver(pca_isa_driver, 1); diff --git a/drivers/i2c/busses/i2c-pca-platform.c b/drivers/i2c/busses/i2c-pca-platform.c new file mode 100644 index 000000000..b8d5480c5 --- /dev/null +++ b/drivers/i2c/busses/i2c-pca-platform.c @@ -0,0 +1,252 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * i2c_pca_platform.c + * + * Platform driver for the PCA9564 I2C controller. + * + * Copyright (C) 2008 Pengutronix + * + + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/jiffies.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/i2c-algo-pca.h> +#include <linux/platform_data/i2c-pca-platform.h> +#include <linux/gpio/consumer.h> +#include <linux/io.h> +#include <linux/of.h> + +#include <asm/irq.h> + +struct i2c_pca_pf_data { + void __iomem *reg_base; + int irq; /* if 0, use polling */ + struct gpio_desc *gpio; + wait_queue_head_t wait; + struct i2c_adapter adap; + struct i2c_algo_pca_data algo_data; +}; + +/* Read/Write functions for different register alignments */ + +static int i2c_pca_pf_readbyte8(void *pd, int reg) +{ + struct i2c_pca_pf_data *i2c = pd; + return ioread8(i2c->reg_base + reg); +} + +static int i2c_pca_pf_readbyte16(void *pd, int reg) +{ + struct i2c_pca_pf_data *i2c = pd; + return ioread8(i2c->reg_base + reg * 2); +} + +static int i2c_pca_pf_readbyte32(void *pd, int reg) +{ + struct i2c_pca_pf_data *i2c = pd; + return ioread8(i2c->reg_base + reg * 4); +} + +static void i2c_pca_pf_writebyte8(void *pd, int reg, int val) +{ + struct i2c_pca_pf_data *i2c = pd; + iowrite8(val, i2c->reg_base + reg); +} + +static void i2c_pca_pf_writebyte16(void *pd, int reg, int val) +{ + struct i2c_pca_pf_data *i2c = pd; + iowrite8(val, i2c->reg_base + reg * 2); +} + +static void i2c_pca_pf_writebyte32(void *pd, int reg, int val) +{ + struct i2c_pca_pf_data *i2c = pd; + iowrite8(val, i2c->reg_base + reg * 4); +} + + +static int i2c_pca_pf_waitforcompletion(void *pd) +{ + struct i2c_pca_pf_data *i2c = pd; + unsigned long timeout; + long ret; + + if (i2c->irq) { + ret = wait_event_timeout(i2c->wait, + i2c->algo_data.read_byte(i2c, I2C_PCA_CON) + & I2C_PCA_CON_SI, i2c->adap.timeout); + } else { + /* Do polling */ + timeout = jiffies + i2c->adap.timeout; + do { + ret = time_before(jiffies, timeout); + if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON) + & I2C_PCA_CON_SI) + break; + udelay(100); + } while (ret); + } + + return ret > 0; +} + +static void i2c_pca_pf_dummyreset(void *pd) +{ + struct i2c_pca_pf_data *i2c = pd; + + dev_warn(&i2c->adap.dev, "No reset-pin found. Chip may get stuck!\n"); +} + +static void i2c_pca_pf_resetchip(void *pd) +{ + struct i2c_pca_pf_data *i2c = pd; + + gpiod_set_value(i2c->gpio, 1); + ndelay(100); + gpiod_set_value(i2c->gpio, 0); +} + +static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id) +{ + struct i2c_pca_pf_data *i2c = dev_id; + + if ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0) + return IRQ_NONE; + + wake_up(&i2c->wait); + + return IRQ_HANDLED; +} + + +static int i2c_pca_pf_probe(struct platform_device *pdev) +{ + struct i2c_pca_pf_data *i2c; + struct resource *res; + struct i2c_pca9564_pf_platform_data *platform_data = + dev_get_platdata(&pdev->dev); + struct device_node *np = pdev->dev.of_node; + int ret = 0; + int irq; + + irq = platform_get_irq_optional(pdev, 0); + /* If irq is 0, we do polling. */ + if (irq < 0) + irq = 0; + + i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->reg_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(i2c->reg_base)) + return PTR_ERR(i2c->reg_base); + + + init_waitqueue_head(&i2c->wait); + + i2c->irq = irq; + + i2c->adap.nr = pdev->id; + i2c->adap.owner = THIS_MODULE; + snprintf(i2c->adap.name, sizeof(i2c->adap.name), + "PCA9564/PCA9665 at 0x%08lx", + (unsigned long) res->start); + i2c->adap.algo_data = &i2c->algo_data; + i2c->adap.dev.parent = &pdev->dev; + i2c->adap.dev.of_node = np; + + i2c->gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_OUT_LOW); + if (IS_ERR(i2c->gpio)) + return PTR_ERR(i2c->gpio); + + i2c->adap.timeout = HZ; + ret = device_property_read_u32(&pdev->dev, "clock-frequency", + &i2c->algo_data.i2c_clock); + if (ret) + i2c->algo_data.i2c_clock = 59000; + + if (platform_data) { + i2c->adap.timeout = platform_data->timeout; + i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed; + } + + i2c->algo_data.data = i2c; + i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion; + if (i2c->gpio) + i2c->algo_data.reset_chip = i2c_pca_pf_resetchip; + else + i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset; + + switch (res->flags & IORESOURCE_MEM_TYPE_MASK) { + case IORESOURCE_MEM_32BIT: + i2c->algo_data.write_byte = i2c_pca_pf_writebyte32; + i2c->algo_data.read_byte = i2c_pca_pf_readbyte32; + break; + case IORESOURCE_MEM_16BIT: + i2c->algo_data.write_byte = i2c_pca_pf_writebyte16; + i2c->algo_data.read_byte = i2c_pca_pf_readbyte16; + break; + case IORESOURCE_MEM_8BIT: + default: + i2c->algo_data.write_byte = i2c_pca_pf_writebyte8; + i2c->algo_data.read_byte = i2c_pca_pf_readbyte8; + break; + } + + if (irq) { + ret = devm_request_irq(&pdev->dev, irq, i2c_pca_pf_handler, + IRQF_TRIGGER_FALLING, pdev->name, i2c); + if (ret) + return ret; + } + + ret = i2c_pca_add_numbered_bus(&i2c->adap); + if (ret) + return ret; + + platform_set_drvdata(pdev, i2c); + + dev_info(&pdev->dev, "registered.\n"); + + return 0; +} + +static void i2c_pca_pf_remove(struct platform_device *pdev) +{ + struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adap); +} + +#ifdef CONFIG_OF +static const struct of_device_id i2c_pca_of_match_table[] = { + { .compatible = "nxp,pca9564" }, + { .compatible = "nxp,pca9665" }, + {}, +}; +MODULE_DEVICE_TABLE(of, i2c_pca_of_match_table); +#endif + +static struct platform_driver i2c_pca_pf_driver = { + .probe = i2c_pca_pf_probe, + .remove_new = i2c_pca_pf_remove, + .driver = { + .name = "i2c-pca-platform", + .of_match_table = of_match_ptr(i2c_pca_of_match_table), + }, +}; + +module_platform_driver(i2c_pca_pf_driver); + +MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>"); +MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c new file mode 100644 index 000000000..809fbd014 --- /dev/null +++ b/drivers/i2c/busses/i2c-piix4.c @@ -0,0 +1,1158 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl> and + Philip Edelbrock <phil@netroedge.com> + +*/ + +/* + Supports: + Intel PIIX4, 440MX + Serverworks OSB4, CSB5, CSB6, HT-1000, HT-1100 + ATI IXP200, IXP300, IXP400, SB600, SB700/SP5100, SB800 + AMD Hudson-2, ML, CZ + Hygon CZ + SMSC Victory66 + + Note: we assume there can only be one device, with one or more + SMBus interfaces. + The device can register multiple i2c_adapters (up to PIIX4_MAX_ADAPTERS). + For devices supporting multiple ports the i2c_adapter should provide + an i2c_algorithm to access them. +*/ + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/stddef.h> +#include <linux/ioport.h> +#include <linux/i2c.h> +#include <linux/slab.h> +#include <linux/dmi.h> +#include <linux/acpi.h> +#include <linux/io.h> + + +/* PIIX4 SMBus address offsets */ +#define SMBHSTSTS (0 + piix4_smba) +#define SMBHSLVSTS (1 + piix4_smba) +#define SMBHSTCNT (2 + piix4_smba) +#define SMBHSTCMD (3 + piix4_smba) +#define SMBHSTADD (4 + piix4_smba) +#define SMBHSTDAT0 (5 + piix4_smba) +#define SMBHSTDAT1 (6 + piix4_smba) +#define SMBBLKDAT (7 + piix4_smba) +#define SMBSLVCNT (8 + piix4_smba) +#define SMBSHDWCMD (9 + piix4_smba) +#define SMBSLVEVT (0xA + piix4_smba) +#define SMBSLVDAT (0xC + piix4_smba) + +/* count for request_region */ +#define SMBIOSIZE 9 + +/* PCI Address Constants */ +#define SMBBA 0x090 +#define SMBHSTCFG 0x0D2 +#define SMBSLVC 0x0D3 +#define SMBSHDW1 0x0D4 +#define SMBSHDW2 0x0D5 +#define SMBREV 0x0D6 + +/* Other settings */ +#define MAX_TIMEOUT 500 +#define ENABLE_INT9 0 + +/* PIIX4 constants */ +#define PIIX4_QUICK 0x00 +#define PIIX4_BYTE 0x04 +#define PIIX4_BYTE_DATA 0x08 +#define PIIX4_WORD_DATA 0x0C +#define PIIX4_BLOCK_DATA 0x14 + +/* Multi-port constants */ +#define PIIX4_MAX_ADAPTERS 4 +#define HUDSON2_MAIN_PORTS 2 /* HUDSON2, KERNCZ reserves ports 3, 4 */ + +/* SB800 constants */ +#define SB800_PIIX4_SMB_IDX 0xcd6 +#define SB800_PIIX4_SMB_MAP_SIZE 2 + +#define KERNCZ_IMC_IDX 0x3e +#define KERNCZ_IMC_DATA 0x3f + +/* + * SB800 port is selected by bits 2:1 of the smb_en register (0x2c) + * or the smb_sel register (0x2e), depending on bit 0 of register 0x2f. + * Hudson-2/Bolton port is always selected by bits 2:1 of register 0x2f. + */ +#define SB800_PIIX4_PORT_IDX 0x2c +#define SB800_PIIX4_PORT_IDX_ALT 0x2e +#define SB800_PIIX4_PORT_IDX_SEL 0x2f +#define SB800_PIIX4_PORT_IDX_MASK 0x06 +#define SB800_PIIX4_PORT_IDX_SHIFT 1 + +/* On kerncz and Hudson2, SmBus0Sel is at bit 20:19 of PMx00 DecodeEn */ +#define SB800_PIIX4_PORT_IDX_KERNCZ 0x02 +#define SB800_PIIX4_PORT_IDX_MASK_KERNCZ 0x18 +#define SB800_PIIX4_PORT_IDX_SHIFT_KERNCZ 3 + +#define SB800_PIIX4_FCH_PM_ADDR 0xFED80300 +#define SB800_PIIX4_FCH_PM_SIZE 8 + +/* insmod parameters */ + +/* If force is set to anything different from 0, we forcibly enable the + PIIX4. DANGEROUS! */ +static int force; +module_param (force, int, 0); +MODULE_PARM_DESC(force, "Forcibly enable the PIIX4. DANGEROUS!"); + +/* If force_addr is set to anything different from 0, we forcibly enable + the PIIX4 at the given address. VERY DANGEROUS! */ +static int force_addr; +module_param_hw(force_addr, int, ioport, 0); +MODULE_PARM_DESC(force_addr, + "Forcibly enable the PIIX4 at the given address. " + "EXTREMELY DANGEROUS!"); + +static int srvrworks_csb5_delay; +static struct pci_driver piix4_driver; + +static const struct dmi_system_id piix4_dmi_blacklist[] = { + { + .ident = "Sapphire AM2RD790", + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "SAPPHIRE Inc."), + DMI_MATCH(DMI_BOARD_NAME, "PC-AM2RD790"), + }, + }, + { + .ident = "DFI Lanparty UT 790FX", + .matches = { + DMI_MATCH(DMI_BOARD_VENDOR, "DFI Inc."), + DMI_MATCH(DMI_BOARD_NAME, "LP UT 790FX"), + }, + }, + { } +}; + +/* The IBM entry is in a separate table because we only check it + on Intel-based systems */ +static const struct dmi_system_id piix4_dmi_ibm[] = { + { + .ident = "IBM", + .matches = { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), }, + }, + { }, +}; + +/* + * SB800 globals + */ +static u8 piix4_port_sel_sb800; +static u8 piix4_port_mask_sb800; +static u8 piix4_port_shift_sb800; +static const char *piix4_main_port_names_sb800[PIIX4_MAX_ADAPTERS] = { + " port 0", " port 2", " port 3", " port 4" +}; +static const char *piix4_aux_port_name_sb800 = " port 1"; + +struct sb800_mmio_cfg { + void __iomem *addr; + bool use_mmio; +}; + +struct i2c_piix4_adapdata { + unsigned short smba; + + /* SB800 */ + bool sb800_main; + bool notify_imc; + u8 port; /* Port number, shifted */ + struct sb800_mmio_cfg mmio_cfg; +}; + +static int piix4_sb800_region_request(struct device *dev, + struct sb800_mmio_cfg *mmio_cfg) +{ + if (mmio_cfg->use_mmio) { + void __iomem *addr; + + if (!request_mem_region_muxed(SB800_PIIX4_FCH_PM_ADDR, + SB800_PIIX4_FCH_PM_SIZE, + "sb800_piix4_smb")) { + dev_err(dev, + "SMBus base address memory region 0x%x already in use.\n", + SB800_PIIX4_FCH_PM_ADDR); + return -EBUSY; + } + + addr = ioremap(SB800_PIIX4_FCH_PM_ADDR, + SB800_PIIX4_FCH_PM_SIZE); + if (!addr) { + release_mem_region(SB800_PIIX4_FCH_PM_ADDR, + SB800_PIIX4_FCH_PM_SIZE); + dev_err(dev, "SMBus base address mapping failed.\n"); + return -ENOMEM; + } + + mmio_cfg->addr = addr; + + return 0; + } + + if (!request_muxed_region(SB800_PIIX4_SMB_IDX, SB800_PIIX4_SMB_MAP_SIZE, + "sb800_piix4_smb")) { + dev_err(dev, + "SMBus base address index region 0x%x already in use.\n", + SB800_PIIX4_SMB_IDX); + return -EBUSY; + } + + return 0; +} + +static void piix4_sb800_region_release(struct device *dev, + struct sb800_mmio_cfg *mmio_cfg) +{ + if (mmio_cfg->use_mmio) { + iounmap(mmio_cfg->addr); + release_mem_region(SB800_PIIX4_FCH_PM_ADDR, + SB800_PIIX4_FCH_PM_SIZE); + return; + } + + release_region(SB800_PIIX4_SMB_IDX, SB800_PIIX4_SMB_MAP_SIZE); +} + +static bool piix4_sb800_use_mmio(struct pci_dev *PIIX4_dev) +{ + /* + * cd6h/cd7h port I/O accesses can be disabled on AMD processors + * w/ SMBus PCI revision ID 0x51 or greater. MMIO is supported on + * the same processors and is the recommended access method. + */ + return (PIIX4_dev->vendor == PCI_VENDOR_ID_AMD && + PIIX4_dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS && + PIIX4_dev->revision >= 0x51); +} + +static int piix4_setup(struct pci_dev *PIIX4_dev, + const struct pci_device_id *id) +{ + unsigned char temp; + unsigned short piix4_smba; + + if ((PIIX4_dev->vendor == PCI_VENDOR_ID_SERVERWORKS) && + (PIIX4_dev->device == PCI_DEVICE_ID_SERVERWORKS_CSB5)) + srvrworks_csb5_delay = 1; + + /* On some motherboards, it was reported that accessing the SMBus + caused severe hardware problems */ + if (dmi_check_system(piix4_dmi_blacklist)) { + dev_err(&PIIX4_dev->dev, + "Accessing the SMBus on this system is unsafe!\n"); + return -EPERM; + } + + /* Don't access SMBus on IBM systems which get corrupted eeproms */ + if (dmi_check_system(piix4_dmi_ibm) && + PIIX4_dev->vendor == PCI_VENDOR_ID_INTEL) { + dev_err(&PIIX4_dev->dev, "IBM system detected; this module " + "may corrupt your serial eeprom! Refusing to load " + "module!\n"); + return -EPERM; + } + + /* Determine the address of the SMBus areas */ + if (force_addr) { + piix4_smba = force_addr & 0xfff0; + force = 0; + } else { + pci_read_config_word(PIIX4_dev, SMBBA, &piix4_smba); + piix4_smba &= 0xfff0; + if(piix4_smba == 0) { + dev_err(&PIIX4_dev->dev, "SMBus base address " + "uninitialized - upgrade BIOS or use " + "force_addr=0xaddr\n"); + return -ENODEV; + } + } + + if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) + return -ENODEV; + + if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) { + dev_err(&PIIX4_dev->dev, "SMBus region 0x%x already in use!\n", + piix4_smba); + return -EBUSY; + } + + pci_read_config_byte(PIIX4_dev, SMBHSTCFG, &temp); + + /* If force_addr is set, we program the new address here. Just to make + sure, we disable the PIIX4 first. */ + if (force_addr) { + pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp & 0xfe); + pci_write_config_word(PIIX4_dev, SMBBA, piix4_smba); + pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp | 0x01); + dev_info(&PIIX4_dev->dev, "WARNING: SMBus interface set to " + "new address %04x!\n", piix4_smba); + } else if ((temp & 1) == 0) { + if (force) { + /* This should never need to be done, but has been + * noted that many Dell machines have the SMBus + * interface on the PIIX4 disabled!? NOTE: This assumes + * I/O space and other allocations WERE done by the + * Bios! Don't complain if your hardware does weird + * things after enabling this. :') Check for Bios + * updates before resorting to this. + */ + pci_write_config_byte(PIIX4_dev, SMBHSTCFG, + temp | 1); + dev_notice(&PIIX4_dev->dev, + "WARNING: SMBus interface has been FORCEFULLY ENABLED!\n"); + } else { + dev_err(&PIIX4_dev->dev, + "SMBus Host Controller not enabled!\n"); + release_region(piix4_smba, SMBIOSIZE); + return -ENODEV; + } + } + + if (((temp & 0x0E) == 8) || ((temp & 0x0E) == 2)) + dev_dbg(&PIIX4_dev->dev, "Using IRQ for SMBus\n"); + else if ((temp & 0x0E) == 0) + dev_dbg(&PIIX4_dev->dev, "Using SMI# for SMBus\n"); + else + dev_err(&PIIX4_dev->dev, "Illegal Interrupt configuration " + "(or code out of date)!\n"); + + pci_read_config_byte(PIIX4_dev, SMBREV, &temp); + dev_info(&PIIX4_dev->dev, + "SMBus Host Controller at 0x%x, revision %d\n", + piix4_smba, temp); + + return piix4_smba; +} + +static int piix4_setup_sb800_smba(struct pci_dev *PIIX4_dev, + u8 smb_en, + u8 aux, + u8 *smb_en_status, + unsigned short *piix4_smba) +{ + struct sb800_mmio_cfg mmio_cfg; + u8 smba_en_lo; + u8 smba_en_hi; + int retval; + + mmio_cfg.use_mmio = piix4_sb800_use_mmio(PIIX4_dev); + retval = piix4_sb800_region_request(&PIIX4_dev->dev, &mmio_cfg); + if (retval) + return retval; + + if (mmio_cfg.use_mmio) { + smba_en_lo = ioread8(mmio_cfg.addr); + smba_en_hi = ioread8(mmio_cfg.addr + 1); + } else { + outb_p(smb_en, SB800_PIIX4_SMB_IDX); + smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1); + outb_p(smb_en + 1, SB800_PIIX4_SMB_IDX); + smba_en_hi = inb_p(SB800_PIIX4_SMB_IDX + 1); + } + + piix4_sb800_region_release(&PIIX4_dev->dev, &mmio_cfg); + + if (!smb_en) { + *smb_en_status = smba_en_lo & 0x10; + *piix4_smba = smba_en_hi << 8; + if (aux) + *piix4_smba |= 0x20; + } else { + *smb_en_status = smba_en_lo & 0x01; + *piix4_smba = ((smba_en_hi << 8) | smba_en_lo) & 0xffe0; + } + + if (!*smb_en_status) { + dev_err(&PIIX4_dev->dev, + "SMBus Host Controller not enabled!\n"); + return -ENODEV; + } + + return 0; +} + +static int piix4_setup_sb800(struct pci_dev *PIIX4_dev, + const struct pci_device_id *id, u8 aux) +{ + unsigned short piix4_smba; + u8 smb_en, smb_en_status, port_sel; + u8 i2ccfg, i2ccfg_offset = 0x10; + struct sb800_mmio_cfg mmio_cfg; + int retval; + + /* SB800 and later SMBus does not support forcing address */ + if (force || force_addr) { + dev_err(&PIIX4_dev->dev, "SMBus does not support " + "forcing address!\n"); + return -EINVAL; + } + + /* Determine the address of the SMBus areas */ + if ((PIIX4_dev->vendor == PCI_VENDOR_ID_AMD && + PIIX4_dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS && + PIIX4_dev->revision >= 0x41) || + (PIIX4_dev->vendor == PCI_VENDOR_ID_AMD && + PIIX4_dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS && + PIIX4_dev->revision >= 0x49) || + (PIIX4_dev->vendor == PCI_VENDOR_ID_HYGON && + PIIX4_dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS)) + smb_en = 0x00; + else + smb_en = (aux) ? 0x28 : 0x2c; + + retval = piix4_setup_sb800_smba(PIIX4_dev, smb_en, aux, &smb_en_status, + &piix4_smba); + + if (retval) + return retval; + + if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) + return -ENODEV; + + if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) { + dev_err(&PIIX4_dev->dev, "SMBus region 0x%x already in use!\n", + piix4_smba); + return -EBUSY; + } + + /* Aux SMBus does not support IRQ information */ + if (aux) { + dev_info(&PIIX4_dev->dev, + "Auxiliary SMBus Host Controller at 0x%x\n", + piix4_smba); + return piix4_smba; + } + + /* Request the SMBus I2C bus config region */ + if (!request_region(piix4_smba + i2ccfg_offset, 1, "i2ccfg")) { + dev_err(&PIIX4_dev->dev, "SMBus I2C bus config region " + "0x%x already in use!\n", piix4_smba + i2ccfg_offset); + release_region(piix4_smba, SMBIOSIZE); + return -EBUSY; + } + i2ccfg = inb_p(piix4_smba + i2ccfg_offset); + release_region(piix4_smba + i2ccfg_offset, 1); + + if (i2ccfg & 1) + dev_dbg(&PIIX4_dev->dev, "Using IRQ for SMBus\n"); + else + dev_dbg(&PIIX4_dev->dev, "Using SMI# for SMBus\n"); + + dev_info(&PIIX4_dev->dev, + "SMBus Host Controller at 0x%x, revision %d\n", + piix4_smba, i2ccfg >> 4); + + /* Find which register is used for port selection */ + if (PIIX4_dev->vendor == PCI_VENDOR_ID_AMD || + PIIX4_dev->vendor == PCI_VENDOR_ID_HYGON) { + if (PIIX4_dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS || + (PIIX4_dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS && + PIIX4_dev->revision >= 0x1F)) { + piix4_port_sel_sb800 = SB800_PIIX4_PORT_IDX_KERNCZ; + piix4_port_mask_sb800 = SB800_PIIX4_PORT_IDX_MASK_KERNCZ; + piix4_port_shift_sb800 = SB800_PIIX4_PORT_IDX_SHIFT_KERNCZ; + } else { + piix4_port_sel_sb800 = SB800_PIIX4_PORT_IDX_ALT; + piix4_port_mask_sb800 = SB800_PIIX4_PORT_IDX_MASK; + piix4_port_shift_sb800 = SB800_PIIX4_PORT_IDX_SHIFT; + } + } else { + mmio_cfg.use_mmio = piix4_sb800_use_mmio(PIIX4_dev); + retval = piix4_sb800_region_request(&PIIX4_dev->dev, &mmio_cfg); + if (retval) { + release_region(piix4_smba, SMBIOSIZE); + return retval; + } + + outb_p(SB800_PIIX4_PORT_IDX_SEL, SB800_PIIX4_SMB_IDX); + port_sel = inb_p(SB800_PIIX4_SMB_IDX + 1); + piix4_port_sel_sb800 = (port_sel & 0x01) ? + SB800_PIIX4_PORT_IDX_ALT : + SB800_PIIX4_PORT_IDX; + piix4_port_mask_sb800 = SB800_PIIX4_PORT_IDX_MASK; + piix4_port_shift_sb800 = SB800_PIIX4_PORT_IDX_SHIFT; + piix4_sb800_region_release(&PIIX4_dev->dev, &mmio_cfg); + } + + dev_info(&PIIX4_dev->dev, + "Using register 0x%02x for SMBus port selection\n", + (unsigned int)piix4_port_sel_sb800); + + return piix4_smba; +} + +static int piix4_setup_aux(struct pci_dev *PIIX4_dev, + const struct pci_device_id *id, + unsigned short base_reg_addr) +{ + /* Set up auxiliary SMBus controllers found on some + * AMD chipsets e.g. SP5100 (SB700 derivative) */ + + unsigned short piix4_smba; + + /* Read address of auxiliary SMBus controller */ + pci_read_config_word(PIIX4_dev, base_reg_addr, &piix4_smba); + if ((piix4_smba & 1) == 0) { + dev_dbg(&PIIX4_dev->dev, + "Auxiliary SMBus controller not enabled\n"); + return -ENODEV; + } + + piix4_smba &= 0xfff0; + if (piix4_smba == 0) { + dev_dbg(&PIIX4_dev->dev, + "Auxiliary SMBus base address uninitialized\n"); + return -ENODEV; + } + + if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) + return -ENODEV; + + if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) { + dev_err(&PIIX4_dev->dev, "Auxiliary SMBus region 0x%x " + "already in use!\n", piix4_smba); + return -EBUSY; + } + + dev_info(&PIIX4_dev->dev, + "Auxiliary SMBus Host Controller at 0x%x\n", + piix4_smba); + + return piix4_smba; +} + +static int piix4_transaction(struct i2c_adapter *piix4_adapter) +{ + struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(piix4_adapter); + unsigned short piix4_smba = adapdata->smba; + int temp; + int result = 0; + int timeout = 0; + + dev_dbg(&piix4_adapter->dev, "Transaction (pre): CNT=%02x, CMD=%02x, " + "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT), + inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), + inb_p(SMBHSTDAT1)); + + /* Make sure the SMBus host is ready to start transmitting */ + if ((temp = inb_p(SMBHSTSTS)) != 0x00) { + dev_dbg(&piix4_adapter->dev, "SMBus busy (%02x). " + "Resetting...\n", temp); + outb_p(temp, SMBHSTSTS); + if ((temp = inb_p(SMBHSTSTS)) != 0x00) { + dev_err(&piix4_adapter->dev, "Failed! (%02x)\n", temp); + return -EBUSY; + } else { + dev_dbg(&piix4_adapter->dev, "Successful!\n"); + } + } + + /* start the transaction by setting bit 6 */ + outb_p(inb(SMBHSTCNT) | 0x040, SMBHSTCNT); + + /* We will always wait for a fraction of a second! (See PIIX4 docs errata) */ + if (srvrworks_csb5_delay) /* Extra delay for SERVERWORKS_CSB5 */ + usleep_range(2000, 2100); + else + usleep_range(250, 500); + + while ((++timeout < MAX_TIMEOUT) && + ((temp = inb_p(SMBHSTSTS)) & 0x01)) + usleep_range(250, 500); + + /* If the SMBus is still busy, we give up */ + if (timeout == MAX_TIMEOUT) { + dev_err(&piix4_adapter->dev, "SMBus Timeout!\n"); + result = -ETIMEDOUT; + } + + if (temp & 0x10) { + result = -EIO; + dev_err(&piix4_adapter->dev, "Error: Failed bus transaction\n"); + } + + if (temp & 0x08) { + result = -EIO; + dev_dbg(&piix4_adapter->dev, "Bus collision! SMBus may be " + "locked until next hard reset. (sorry!)\n"); + /* Clock stops and slave is stuck in mid-transmission */ + } + + if (temp & 0x04) { + result = -ENXIO; + dev_dbg(&piix4_adapter->dev, "Error: no response!\n"); + } + + if (inb_p(SMBHSTSTS) != 0x00) + outb_p(inb(SMBHSTSTS), SMBHSTSTS); + + if ((temp = inb_p(SMBHSTSTS)) != 0x00) { + dev_err(&piix4_adapter->dev, "Failed reset at end of " + "transaction (%02x)\n", temp); + } + dev_dbg(&piix4_adapter->dev, "Transaction (post): CNT=%02x, CMD=%02x, " + "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT), + inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), + inb_p(SMBHSTDAT1)); + return result; +} + +/* Return negative errno on error. */ +static s32 piix4_access(struct i2c_adapter * adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data * data) +{ + struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap); + unsigned short piix4_smba = adapdata->smba; + int i, len; + int status; + + switch (size) { + case I2C_SMBUS_QUICK: + outb_p((addr << 1) | read_write, + SMBHSTADD); + size = PIIX4_QUICK; + break; + case I2C_SMBUS_BYTE: + outb_p((addr << 1) | read_write, + SMBHSTADD); + if (read_write == I2C_SMBUS_WRITE) + outb_p(command, SMBHSTCMD); + size = PIIX4_BYTE; + break; + case I2C_SMBUS_BYTE_DATA: + outb_p((addr << 1) | read_write, + SMBHSTADD); + outb_p(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) + outb_p(data->byte, SMBHSTDAT0); + size = PIIX4_BYTE_DATA; + break; + case I2C_SMBUS_WORD_DATA: + outb_p((addr << 1) | read_write, + SMBHSTADD); + outb_p(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) { + outb_p(data->word & 0xff, SMBHSTDAT0); + outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1); + } + size = PIIX4_WORD_DATA; + break; + case I2C_SMBUS_BLOCK_DATA: + outb_p((addr << 1) | read_write, + SMBHSTADD); + outb_p(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) { + len = data->block[0]; + if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) + return -EINVAL; + outb_p(len, SMBHSTDAT0); + inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */ + for (i = 1; i <= len; i++) + outb_p(data->block[i], SMBBLKDAT); + } + size = PIIX4_BLOCK_DATA; + break; + default: + dev_warn(&adap->dev, "Unsupported transaction %d\n", size); + return -EOPNOTSUPP; + } + + outb_p((size & 0x1C) + (ENABLE_INT9 & 1), SMBHSTCNT); + + status = piix4_transaction(adap); + if (status) + return status; + + if ((read_write == I2C_SMBUS_WRITE) || (size == PIIX4_QUICK)) + return 0; + + + switch (size) { + case PIIX4_BYTE: + case PIIX4_BYTE_DATA: + data->byte = inb_p(SMBHSTDAT0); + break; + case PIIX4_WORD_DATA: + data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8); + break; + case PIIX4_BLOCK_DATA: + data->block[0] = inb_p(SMBHSTDAT0); + if (data->block[0] == 0 || data->block[0] > I2C_SMBUS_BLOCK_MAX) + return -EPROTO; + inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */ + for (i = 1; i <= data->block[0]; i++) + data->block[i] = inb_p(SMBBLKDAT); + break; + } + return 0; +} + +static uint8_t piix4_imc_read(uint8_t idx) +{ + outb_p(idx, KERNCZ_IMC_IDX); + return inb_p(KERNCZ_IMC_DATA); +} + +static void piix4_imc_write(uint8_t idx, uint8_t value) +{ + outb_p(idx, KERNCZ_IMC_IDX); + outb_p(value, KERNCZ_IMC_DATA); +} + +static int piix4_imc_sleep(void) +{ + int timeout = MAX_TIMEOUT; + + if (!request_muxed_region(KERNCZ_IMC_IDX, 2, "smbus_kerncz_imc")) + return -EBUSY; + + /* clear response register */ + piix4_imc_write(0x82, 0x00); + /* request ownership flag */ + piix4_imc_write(0x83, 0xB4); + /* kick off IMC Mailbox command 96 */ + piix4_imc_write(0x80, 0x96); + + while (timeout--) { + if (piix4_imc_read(0x82) == 0xfa) { + release_region(KERNCZ_IMC_IDX, 2); + return 0; + } + usleep_range(1000, 2000); + } + + release_region(KERNCZ_IMC_IDX, 2); + return -ETIMEDOUT; +} + +static void piix4_imc_wakeup(void) +{ + int timeout = MAX_TIMEOUT; + + if (!request_muxed_region(KERNCZ_IMC_IDX, 2, "smbus_kerncz_imc")) + return; + + /* clear response register */ + piix4_imc_write(0x82, 0x00); + /* release ownership flag */ + piix4_imc_write(0x83, 0xB5); + /* kick off IMC Mailbox command 96 */ + piix4_imc_write(0x80, 0x96); + + while (timeout--) { + if (piix4_imc_read(0x82) == 0xfa) + break; + usleep_range(1000, 2000); + } + + release_region(KERNCZ_IMC_IDX, 2); +} + +static int piix4_sb800_port_sel(u8 port, struct sb800_mmio_cfg *mmio_cfg) +{ + u8 smba_en_lo, val; + + if (mmio_cfg->use_mmio) { + smba_en_lo = ioread8(mmio_cfg->addr + piix4_port_sel_sb800); + val = (smba_en_lo & ~piix4_port_mask_sb800) | port; + if (smba_en_lo != val) + iowrite8(val, mmio_cfg->addr + piix4_port_sel_sb800); + + return (smba_en_lo & piix4_port_mask_sb800); + } + + outb_p(piix4_port_sel_sb800, SB800_PIIX4_SMB_IDX); + smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1); + + val = (smba_en_lo & ~piix4_port_mask_sb800) | port; + if (smba_en_lo != val) + outb_p(val, SB800_PIIX4_SMB_IDX + 1); + + return (smba_en_lo & piix4_port_mask_sb800); +} + +/* + * Handles access to multiple SMBus ports on the SB800. + * The port is selected by bits 2:1 of the smb_en register (0x2c). + * Returns negative errno on error. + * + * Note: The selected port must be returned to the initial selection to avoid + * problems on certain systems. + */ +static s32 piix4_access_sb800(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data *data) +{ + struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap); + unsigned short piix4_smba = adapdata->smba; + int retries = MAX_TIMEOUT; + int smbslvcnt; + u8 prev_port; + int retval; + + retval = piix4_sb800_region_request(&adap->dev, &adapdata->mmio_cfg); + if (retval) + return retval; + + /* Request the SMBUS semaphore, avoid conflicts with the IMC */ + smbslvcnt = inb_p(SMBSLVCNT); + do { + outb_p(smbslvcnt | 0x10, SMBSLVCNT); + + /* Check the semaphore status */ + smbslvcnt = inb_p(SMBSLVCNT); + if (smbslvcnt & 0x10) + break; + + usleep_range(1000, 2000); + } while (--retries); + /* SMBus is still owned by the IMC, we give up */ + if (!retries) { + retval = -EBUSY; + goto release; + } + + /* + * Notify the IMC (Integrated Micro Controller) if required. + * Among other responsibilities, the IMC is in charge of monitoring + * the System fans and temperature sensors, and act accordingly. + * All this is done through SMBus and can/will collide + * with our transactions if they are long (BLOCK_DATA). + * Therefore we need to request the ownership flag during those + * transactions. + */ + if ((size == I2C_SMBUS_BLOCK_DATA) && adapdata->notify_imc) { + int ret; + + ret = piix4_imc_sleep(); + switch (ret) { + case -EBUSY: + dev_warn(&adap->dev, + "IMC base address index region 0x%x already in use.\n", + KERNCZ_IMC_IDX); + break; + case -ETIMEDOUT: + dev_warn(&adap->dev, + "Failed to communicate with the IMC.\n"); + break; + default: + break; + } + + /* If IMC communication fails do not retry */ + if (ret) { + dev_warn(&adap->dev, + "Continuing without IMC notification.\n"); + adapdata->notify_imc = false; + } + } + + prev_port = piix4_sb800_port_sel(adapdata->port, &adapdata->mmio_cfg); + + retval = piix4_access(adap, addr, flags, read_write, + command, size, data); + + piix4_sb800_port_sel(prev_port, &adapdata->mmio_cfg); + + /* Release the semaphore */ + outb_p(smbslvcnt | 0x20, SMBSLVCNT); + + if ((size == I2C_SMBUS_BLOCK_DATA) && adapdata->notify_imc) + piix4_imc_wakeup(); + +release: + piix4_sb800_region_release(&adap->dev, &adapdata->mmio_cfg); + return retval; +} + +static u32 piix4_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_BLOCK_DATA; +} + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = piix4_access, + .functionality = piix4_func, +}; + +static const struct i2c_algorithm piix4_smbus_algorithm_sb800 = { + .smbus_xfer = piix4_access_sb800, + .functionality = piix4_func, +}; + +static const struct pci_device_id piix4_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3) }, + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443MX_3) }, + { PCI_DEVICE(PCI_VENDOR_ID_EFAR, PCI_DEVICE_ID_EFAR_SLC90E66_3) }, + { PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP200_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP300_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP400_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_HUDSON2_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_KERNCZ_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_KERNCZ_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS, + PCI_DEVICE_ID_SERVERWORKS_OSB4) }, + { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS, + PCI_DEVICE_ID_SERVERWORKS_CSB5) }, + { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS, + PCI_DEVICE_ID_SERVERWORKS_CSB6) }, + { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS, + PCI_DEVICE_ID_SERVERWORKS_HT1000SB) }, + { PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS, + PCI_DEVICE_ID_SERVERWORKS_HT1100LD) }, + { 0, } +}; + +MODULE_DEVICE_TABLE (pci, piix4_ids); + +static struct i2c_adapter *piix4_main_adapters[PIIX4_MAX_ADAPTERS]; +static struct i2c_adapter *piix4_aux_adapter; +static int piix4_adapter_count; + +static int piix4_add_adapter(struct pci_dev *dev, unsigned short smba, + bool sb800_main, u8 port, bool notify_imc, + u8 hw_port_nr, const char *name, + struct i2c_adapter **padap) +{ + struct i2c_adapter *adap; + struct i2c_piix4_adapdata *adapdata; + int retval; + + adap = kzalloc(sizeof(*adap), GFP_KERNEL); + if (adap == NULL) { + release_region(smba, SMBIOSIZE); + return -ENOMEM; + } + + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + adap->algo = sb800_main ? &piix4_smbus_algorithm_sb800 + : &smbus_algorithm; + + adapdata = kzalloc(sizeof(*adapdata), GFP_KERNEL); + if (adapdata == NULL) { + kfree(adap); + release_region(smba, SMBIOSIZE); + return -ENOMEM; + } + + adapdata->mmio_cfg.use_mmio = piix4_sb800_use_mmio(dev); + adapdata->smba = smba; + adapdata->sb800_main = sb800_main; + adapdata->port = port << piix4_port_shift_sb800; + adapdata->notify_imc = notify_imc; + + /* set up the sysfs linkage to our parent device */ + adap->dev.parent = &dev->dev; + + if (has_acpi_companion(&dev->dev)) { + acpi_preset_companion(&adap->dev, + ACPI_COMPANION(&dev->dev), + hw_port_nr); + } + + snprintf(adap->name, sizeof(adap->name), + "SMBus PIIX4 adapter%s at %04x", name, smba); + + i2c_set_adapdata(adap, adapdata); + + retval = i2c_add_adapter(adap); + if (retval) { + kfree(adapdata); + kfree(adap); + release_region(smba, SMBIOSIZE); + return retval; + } + + *padap = adap; + return 0; +} + +static int piix4_add_adapters_sb800(struct pci_dev *dev, unsigned short smba, + bool notify_imc) +{ + struct i2c_piix4_adapdata *adapdata; + int port; + int retval; + + if (dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS || + (dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS && + dev->revision >= 0x1F)) { + piix4_adapter_count = HUDSON2_MAIN_PORTS; + } else { + piix4_adapter_count = PIIX4_MAX_ADAPTERS; + } + + for (port = 0; port < piix4_adapter_count; port++) { + u8 hw_port_nr = port == 0 ? 0 : port + 1; + + retval = piix4_add_adapter(dev, smba, true, port, notify_imc, + hw_port_nr, + piix4_main_port_names_sb800[port], + &piix4_main_adapters[port]); + if (retval < 0) + goto error; + } + + return retval; + +error: + dev_err(&dev->dev, + "Error setting up SB800 adapters. Unregistering!\n"); + while (--port >= 0) { + adapdata = i2c_get_adapdata(piix4_main_adapters[port]); + if (adapdata->smba) { + i2c_del_adapter(piix4_main_adapters[port]); + kfree(adapdata); + kfree(piix4_main_adapters[port]); + piix4_main_adapters[port] = NULL; + } + } + + return retval; +} + +static int piix4_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + int retval; + bool is_sb800 = false; + + if ((dev->vendor == PCI_VENDOR_ID_ATI && + dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS && + dev->revision >= 0x40) || + dev->vendor == PCI_VENDOR_ID_AMD || + dev->vendor == PCI_VENDOR_ID_HYGON) { + bool notify_imc = false; + is_sb800 = true; + + if ((dev->vendor == PCI_VENDOR_ID_AMD || + dev->vendor == PCI_VENDOR_ID_HYGON) && + dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS) { + u8 imc; + + /* + * Detect if IMC is active or not, this method is + * described on coreboot's AMD IMC notes + */ + pci_bus_read_config_byte(dev->bus, PCI_DEVFN(0x14, 3), + 0x40, &imc); + if (imc & 0x80) + notify_imc = true; + } + + /* base address location etc changed in SB800 */ + retval = piix4_setup_sb800(dev, id, 0); + if (retval < 0) + return retval; + + /* + * Try to register multiplexed main SMBus adapter, + * give up if we can't + */ + retval = piix4_add_adapters_sb800(dev, retval, notify_imc); + if (retval < 0) + return retval; + } else { + retval = piix4_setup(dev, id); + if (retval < 0) + return retval; + + /* Try to register main SMBus adapter, give up if we can't */ + retval = piix4_add_adapter(dev, retval, false, 0, false, 0, + "", &piix4_main_adapters[0]); + if (retval < 0) + return retval; + piix4_adapter_count = 1; + } + + /* Check for auxiliary SMBus on some AMD chipsets */ + retval = -ENODEV; + + if (dev->vendor == PCI_VENDOR_ID_ATI && + dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS) { + if (dev->revision < 0x40) { + retval = piix4_setup_aux(dev, id, 0x58); + } else { + /* SB800 added aux bus too */ + retval = piix4_setup_sb800(dev, id, 1); + } + } + + if (dev->vendor == PCI_VENDOR_ID_AMD && + (dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS || + dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS)) { + retval = piix4_setup_sb800(dev, id, 1); + } + + if (retval > 0) { + /* Try to add the aux adapter if it exists, + * piix4_add_adapter will clean up if this fails */ + piix4_add_adapter(dev, retval, false, 0, false, 1, + is_sb800 ? piix4_aux_port_name_sb800 : "", + &piix4_aux_adapter); + } + + return 0; +} + +static void piix4_adap_remove(struct i2c_adapter *adap) +{ + struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap); + + if (adapdata->smba) { + i2c_del_adapter(adap); + if (adapdata->port == (0 << piix4_port_shift_sb800)) + release_region(adapdata->smba, SMBIOSIZE); + kfree(adapdata); + kfree(adap); + } +} + +static void piix4_remove(struct pci_dev *dev) +{ + int port = piix4_adapter_count; + + while (--port >= 0) { + if (piix4_main_adapters[port]) { + piix4_adap_remove(piix4_main_adapters[port]); + piix4_main_adapters[port] = NULL; + } + } + + if (piix4_aux_adapter) { + piix4_adap_remove(piix4_aux_adapter); + piix4_aux_adapter = NULL; + } +} + +static struct pci_driver piix4_driver = { + .name = "piix4_smbus", + .id_table = piix4_ids, + .probe = piix4_probe, + .remove = piix4_remove, +}; + +module_pci_driver(piix4_driver); + +MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>"); +MODULE_AUTHOR("Philip Edelbrock <phil@netroedge.com>"); +MODULE_DESCRIPTION("PIIX4 SMBus driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-pnx.c b/drivers/i2c/busses/i2c-pnx.c new file mode 100644 index 000000000..a12525b31 --- /dev/null +++ b/drivers/i2c/busses/i2c-pnx.c @@ -0,0 +1,785 @@ +/* + * Provides I2C support for Philips PNX010x/PNX4008 boards. + * + * Authors: Dennis Kovalev <dkovalev@ru.mvista.com> + * Vitaly Wool <vwool@ru.mvista.com> + * + * 2004-2006 (c) MontaVista Software, Inc. This file is licensed under + * the terms of the GNU General Public License version 2. This program + * is licensed "as is" without any warranty of any kind, whether express + * or implied. + */ + +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/timer.h> +#include <linux/completion.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/slab.h> +#include <linux/of.h> + +#define I2C_PNX_TIMEOUT_DEFAULT 10 /* msec */ +#define I2C_PNX_SPEED_KHZ_DEFAULT 100 +#define I2C_PNX_REGION_SIZE 0x100 + +struct i2c_pnx_mif { + int ret; /* Return value */ + int mode; /* Interface mode */ + struct completion complete; /* I/O completion */ + struct timer_list timer; /* Timeout */ + u8 * buf; /* Data buffer */ + int len; /* Length of data buffer */ + int order; /* RX Bytes to order via TX */ +}; + +struct i2c_pnx_algo_data { + void __iomem *ioaddr; + struct i2c_pnx_mif mif; + int last; + struct clk *clk; + struct i2c_adapter adapter; + int irq; + u32 timeout; +}; + +enum { + mstatus_tdi = 0x00000001, + mstatus_afi = 0x00000002, + mstatus_nai = 0x00000004, + mstatus_drmi = 0x00000008, + mstatus_active = 0x00000020, + mstatus_scl = 0x00000040, + mstatus_sda = 0x00000080, + mstatus_rff = 0x00000100, + mstatus_rfe = 0x00000200, + mstatus_tff = 0x00000400, + mstatus_tfe = 0x00000800, +}; + +enum { + mcntrl_tdie = 0x00000001, + mcntrl_afie = 0x00000002, + mcntrl_naie = 0x00000004, + mcntrl_drmie = 0x00000008, + mcntrl_drsie = 0x00000010, + mcntrl_rffie = 0x00000020, + mcntrl_daie = 0x00000040, + mcntrl_tffie = 0x00000080, + mcntrl_reset = 0x00000100, + mcntrl_cdbmode = 0x00000400, +}; + +enum { + rw_bit = 1 << 0, + start_bit = 1 << 8, + stop_bit = 1 << 9, +}; + +#define I2C_REG_RX(a) ((a)->ioaddr) /* Rx FIFO reg (RO) */ +#define I2C_REG_TX(a) ((a)->ioaddr) /* Tx FIFO reg (WO) */ +#define I2C_REG_STS(a) ((a)->ioaddr + 0x04) /* Status reg (RO) */ +#define I2C_REG_CTL(a) ((a)->ioaddr + 0x08) /* Ctl reg */ +#define I2C_REG_CKL(a) ((a)->ioaddr + 0x0c) /* Clock divider low */ +#define I2C_REG_CKH(a) ((a)->ioaddr + 0x10) /* Clock divider high */ +#define I2C_REG_ADR(a) ((a)->ioaddr + 0x14) /* I2C address */ +#define I2C_REG_RFL(a) ((a)->ioaddr + 0x18) /* Rx FIFO level (RO) */ +#define I2C_REG_TFL(a) ((a)->ioaddr + 0x1c) /* Tx FIFO level (RO) */ +#define I2C_REG_RXB(a) ((a)->ioaddr + 0x20) /* Num of bytes Rx-ed (RO) */ +#define I2C_REG_TXB(a) ((a)->ioaddr + 0x24) /* Num of bytes Tx-ed (RO) */ +#define I2C_REG_TXS(a) ((a)->ioaddr + 0x28) /* Tx slave FIFO (RO) */ +#define I2C_REG_STFL(a) ((a)->ioaddr + 0x2c) /* Tx slave FIFO level (RO) */ + +static inline int wait_timeout(struct i2c_pnx_algo_data *data) +{ + long timeout = data->timeout; + while (timeout > 0 && + (ioread32(I2C_REG_STS(data)) & mstatus_active)) { + mdelay(1); + timeout--; + } + return (timeout <= 0); +} + +static inline int wait_reset(struct i2c_pnx_algo_data *data) +{ + long timeout = data->timeout; + while (timeout > 0 && + (ioread32(I2C_REG_CTL(data)) & mcntrl_reset)) { + mdelay(1); + timeout--; + } + return (timeout <= 0); +} + +static inline void i2c_pnx_arm_timer(struct i2c_pnx_algo_data *alg_data) +{ + struct timer_list *timer = &alg_data->mif.timer; + unsigned long expires = msecs_to_jiffies(alg_data->timeout); + + if (expires <= 1) + expires = 2; + + del_timer_sync(timer); + + dev_dbg(&alg_data->adapter.dev, "Timer armed at %lu plus %lu jiffies.\n", + jiffies, expires); + + timer->expires = jiffies + expires; + + add_timer(timer); +} + +/** + * i2c_pnx_start - start a device + * @slave_addr: slave address + * @alg_data: pointer to local driver data structure + * + * Generate a START signal in the desired mode. + */ +static int i2c_pnx_start(unsigned char slave_addr, + struct i2c_pnx_algo_data *alg_data) +{ + dev_dbg(&alg_data->adapter.dev, "%s(): addr 0x%x mode %d\n", __func__, + slave_addr, alg_data->mif.mode); + + /* Check for 7 bit slave addresses only */ + if (slave_addr & ~0x7f) { + dev_err(&alg_data->adapter.dev, + "%s: Invalid slave address %x. Only 7-bit addresses are supported\n", + alg_data->adapter.name, slave_addr); + return -EINVAL; + } + + /* First, make sure bus is idle */ + if (wait_timeout(alg_data)) { + /* Somebody else is monopolizing the bus */ + dev_err(&alg_data->adapter.dev, + "%s: Bus busy. Slave addr = %02x, cntrl = %x, stat = %x\n", + alg_data->adapter.name, slave_addr, + ioread32(I2C_REG_CTL(alg_data)), + ioread32(I2C_REG_STS(alg_data))); + return -EBUSY; + } else if (ioread32(I2C_REG_STS(alg_data)) & mstatus_afi) { + /* Sorry, we lost the bus */ + dev_err(&alg_data->adapter.dev, + "%s: Arbitration failure. Slave addr = %02x\n", + alg_data->adapter.name, slave_addr); + return -EIO; + } + + /* + * OK, I2C is enabled and we have the bus. + * Clear the current TDI and AFI status flags. + */ + iowrite32(ioread32(I2C_REG_STS(alg_data)) | mstatus_tdi | mstatus_afi, + I2C_REG_STS(alg_data)); + + dev_dbg(&alg_data->adapter.dev, "%s(): sending %#x\n", __func__, + (slave_addr << 1) | start_bit | alg_data->mif.mode); + + /* Write the slave address, START bit and R/W bit */ + iowrite32((slave_addr << 1) | start_bit | alg_data->mif.mode, + I2C_REG_TX(alg_data)); + + dev_dbg(&alg_data->adapter.dev, "%s(): exit\n", __func__); + + return 0; +} + +/** + * i2c_pnx_stop - stop a device + * @alg_data: pointer to local driver data structure + * + * Generate a STOP signal to terminate the master transaction. + */ +static void i2c_pnx_stop(struct i2c_pnx_algo_data *alg_data) +{ + /* Only 1 msec max timeout due to interrupt context */ + long timeout = 1000; + + dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n", + __func__, ioread32(I2C_REG_STS(alg_data))); + + /* Write a STOP bit to TX FIFO */ + iowrite32(0xff | stop_bit, I2C_REG_TX(alg_data)); + + /* Wait until the STOP is seen. */ + while (timeout > 0 && + (ioread32(I2C_REG_STS(alg_data)) & mstatus_active)) { + /* may be called from interrupt context */ + udelay(1); + timeout--; + } + + dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n", + __func__, ioread32(I2C_REG_STS(alg_data))); +} + +/** + * i2c_pnx_master_xmit - transmit data to slave + * @alg_data: pointer to local driver data structure + * + * Sends one byte of data to the slave + */ +static int i2c_pnx_master_xmit(struct i2c_pnx_algo_data *alg_data) +{ + u32 val; + + dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n", + __func__, ioread32(I2C_REG_STS(alg_data))); + + if (alg_data->mif.len > 0) { + /* We still have something to talk about... */ + val = *alg_data->mif.buf++; + + if (alg_data->mif.len == 1) + val |= stop_bit; + + alg_data->mif.len--; + iowrite32(val, I2C_REG_TX(alg_data)); + + dev_dbg(&alg_data->adapter.dev, "%s(): xmit %#x [%d]\n", + __func__, val, alg_data->mif.len + 1); + + if (alg_data->mif.len == 0) { + if (alg_data->last) { + /* Wait until the STOP is seen. */ + if (wait_timeout(alg_data)) + dev_err(&alg_data->adapter.dev, + "The bus is still active after timeout\n"); + } + /* Disable master interrupts */ + iowrite32(ioread32(I2C_REG_CTL(alg_data)) & + ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie), + I2C_REG_CTL(alg_data)); + + del_timer_sync(&alg_data->mif.timer); + + dev_dbg(&alg_data->adapter.dev, + "%s(): Waking up xfer routine.\n", + __func__); + + complete(&alg_data->mif.complete); + } + } else if (alg_data->mif.len == 0) { + /* zero-sized transfer */ + i2c_pnx_stop(alg_data); + + /* Disable master interrupts. */ + iowrite32(ioread32(I2C_REG_CTL(alg_data)) & + ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie), + I2C_REG_CTL(alg_data)); + + /* Stop timer. */ + del_timer_sync(&alg_data->mif.timer); + dev_dbg(&alg_data->adapter.dev, + "%s(): Waking up xfer routine after zero-xfer.\n", + __func__); + + complete(&alg_data->mif.complete); + } + + dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n", + __func__, ioread32(I2C_REG_STS(alg_data))); + + return 0; +} + +/** + * i2c_pnx_master_rcv - receive data from slave + * @alg_data: pointer to local driver data structure + * + * Reads one byte data from the slave + */ +static int i2c_pnx_master_rcv(struct i2c_pnx_algo_data *alg_data) +{ + unsigned int val = 0; + u32 ctl = 0; + + dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n", + __func__, ioread32(I2C_REG_STS(alg_data))); + + /* Check, whether there is already data, + * or we didn't 'ask' for it yet. + */ + if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) { + /* 'Asking' is done asynchronously, e.g. dummy TX of several + * bytes is done before the first actual RX arrives in FIFO. + * Therefore, ordered bytes (via TX) are counted separately. + */ + if (alg_data->mif.order) { + dev_dbg(&alg_data->adapter.dev, + "%s(): Write dummy data to fill Rx-fifo...\n", + __func__); + + if (alg_data->mif.order == 1) { + /* Last byte, do not acknowledge next rcv. */ + val |= stop_bit; + + /* + * Enable interrupt RFDAIE (data in Rx fifo), + * and disable DRMIE (need data for Tx) + */ + ctl = ioread32(I2C_REG_CTL(alg_data)); + ctl |= mcntrl_rffie | mcntrl_daie; + ctl &= ~mcntrl_drmie; + iowrite32(ctl, I2C_REG_CTL(alg_data)); + } + + /* + * Now we'll 'ask' for data: + * For each byte we want to receive, we must + * write a (dummy) byte to the Tx-FIFO. + */ + iowrite32(val, I2C_REG_TX(alg_data)); + alg_data->mif.order--; + } + return 0; + } + + /* Handle data. */ + if (alg_data->mif.len > 0) { + val = ioread32(I2C_REG_RX(alg_data)); + *alg_data->mif.buf++ = (u8) (val & 0xff); + dev_dbg(&alg_data->adapter.dev, "%s(): rcv 0x%x [%d]\n", + __func__, val, alg_data->mif.len); + + alg_data->mif.len--; + if (alg_data->mif.len == 0) { + if (alg_data->last) + /* Wait until the STOP is seen. */ + if (wait_timeout(alg_data)) + dev_err(&alg_data->adapter.dev, + "The bus is still active after timeout\n"); + + /* Disable master interrupts */ + ctl = ioread32(I2C_REG_CTL(alg_data)); + ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | + mcntrl_drmie | mcntrl_daie); + iowrite32(ctl, I2C_REG_CTL(alg_data)); + + /* Kill timer. */ + del_timer_sync(&alg_data->mif.timer); + complete(&alg_data->mif.complete); + } + } + + dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n", + __func__, ioread32(I2C_REG_STS(alg_data))); + + return 0; +} + +static irqreturn_t i2c_pnx_interrupt(int irq, void *dev_id) +{ + struct i2c_pnx_algo_data *alg_data = dev_id; + u32 stat, ctl; + + dev_dbg(&alg_data->adapter.dev, + "%s(): mstat = %x mctrl = %x, mode = %d\n", + __func__, + ioread32(I2C_REG_STS(alg_data)), + ioread32(I2C_REG_CTL(alg_data)), + alg_data->mif.mode); + stat = ioread32(I2C_REG_STS(alg_data)); + + /* let's see what kind of event this is */ + if (stat & mstatus_afi) { + /* We lost arbitration in the midst of a transfer */ + alg_data->mif.ret = -EIO; + + /* Disable master interrupts. */ + ctl = ioread32(I2C_REG_CTL(alg_data)); + ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | + mcntrl_drmie); + iowrite32(ctl, I2C_REG_CTL(alg_data)); + + /* Stop timer, to prevent timeout. */ + del_timer_sync(&alg_data->mif.timer); + complete(&alg_data->mif.complete); + } else if (stat & mstatus_nai) { + /* Slave did not acknowledge, generate a STOP */ + dev_dbg(&alg_data->adapter.dev, + "%s(): Slave did not acknowledge, generating a STOP.\n", + __func__); + i2c_pnx_stop(alg_data); + + /* Disable master interrupts. */ + ctl = ioread32(I2C_REG_CTL(alg_data)); + ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | + mcntrl_drmie); + iowrite32(ctl, I2C_REG_CTL(alg_data)); + + /* Our return value. */ + alg_data->mif.ret = -EIO; + + /* Stop timer, to prevent timeout. */ + del_timer_sync(&alg_data->mif.timer); + complete(&alg_data->mif.complete); + } else { + /* + * Two options: + * - Master Tx needs data. + * - There is data in the Rx-fifo + * The latter is only the case if we have requested for data, + * via a dummy write. (See 'i2c_pnx_master_rcv'.) + * We therefore check, as a sanity check, whether that interrupt + * has been enabled. + */ + if ((stat & mstatus_drmi) || !(stat & mstatus_rfe)) { + if (alg_data->mif.mode == I2C_SMBUS_WRITE) { + i2c_pnx_master_xmit(alg_data); + } else if (alg_data->mif.mode == I2C_SMBUS_READ) { + i2c_pnx_master_rcv(alg_data); + } + } + } + + /* Clear TDI and AFI bits */ + stat = ioread32(I2C_REG_STS(alg_data)); + iowrite32(stat | mstatus_tdi | mstatus_afi, I2C_REG_STS(alg_data)); + + dev_dbg(&alg_data->adapter.dev, + "%s(): exiting, stat = %x ctrl = %x.\n", + __func__, ioread32(I2C_REG_STS(alg_data)), + ioread32(I2C_REG_CTL(alg_data))); + + return IRQ_HANDLED; +} + +static void i2c_pnx_timeout(struct timer_list *t) +{ + struct i2c_pnx_algo_data *alg_data = from_timer(alg_data, t, mif.timer); + u32 ctl; + + dev_err(&alg_data->adapter.dev, + "Master timed out. stat = %04x, cntrl = %04x. Resetting master...\n", + ioread32(I2C_REG_STS(alg_data)), + ioread32(I2C_REG_CTL(alg_data))); + + /* Reset master and disable interrupts */ + ctl = ioread32(I2C_REG_CTL(alg_data)); + ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | mcntrl_drmie); + iowrite32(ctl, I2C_REG_CTL(alg_data)); + + ctl |= mcntrl_reset; + iowrite32(ctl, I2C_REG_CTL(alg_data)); + wait_reset(alg_data); + alg_data->mif.ret = -EIO; + complete(&alg_data->mif.complete); +} + +static inline void bus_reset_if_active(struct i2c_pnx_algo_data *alg_data) +{ + u32 stat; + + if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_active) { + dev_err(&alg_data->adapter.dev, + "%s: Bus is still active after xfer. Reset it...\n", + alg_data->adapter.name); + iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, + I2C_REG_CTL(alg_data)); + wait_reset(alg_data); + } else if (!(stat & mstatus_rfe) || !(stat & mstatus_tfe)) { + /* If there is data in the fifo's after transfer, + * flush fifo's by reset. + */ + iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, + I2C_REG_CTL(alg_data)); + wait_reset(alg_data); + } else if (stat & mstatus_nai) { + iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, + I2C_REG_CTL(alg_data)); + wait_reset(alg_data); + } +} + +/** + * i2c_pnx_xfer - generic transfer entry point + * @adap: pointer to I2C adapter structure + * @msgs: array of messages + * @num: number of messages + * + * Initiates the transfer + */ +static int +i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + struct i2c_msg *pmsg; + int rc = 0, completed = 0, i; + struct i2c_pnx_algo_data *alg_data = adap->algo_data; + u32 stat; + + dev_dbg(&alg_data->adapter.dev, + "%s(): entering: %d messages, stat = %04x.\n", + __func__, num, ioread32(I2C_REG_STS(alg_data))); + + bus_reset_if_active(alg_data); + + /* Process transactions in a loop. */ + for (i = 0; rc >= 0 && i < num; i++) { + u8 addr; + + pmsg = &msgs[i]; + addr = pmsg->addr; + + if (pmsg->flags & I2C_M_TEN) { + dev_err(&alg_data->adapter.dev, + "%s: 10 bits addr not supported!\n", + alg_data->adapter.name); + rc = -EINVAL; + break; + } + + alg_data->mif.buf = pmsg->buf; + alg_data->mif.len = pmsg->len; + alg_data->mif.order = pmsg->len; + alg_data->mif.mode = (pmsg->flags & I2C_M_RD) ? + I2C_SMBUS_READ : I2C_SMBUS_WRITE; + alg_data->mif.ret = 0; + alg_data->last = (i == num - 1); + + dev_dbg(&alg_data->adapter.dev, "%s(): mode %d, %d bytes\n", + __func__, alg_data->mif.mode, alg_data->mif.len); + + i2c_pnx_arm_timer(alg_data); + + /* initialize the completion var */ + init_completion(&alg_data->mif.complete); + + /* Enable master interrupt */ + iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_afie | + mcntrl_naie | mcntrl_drmie, + I2C_REG_CTL(alg_data)); + + /* Put start-code and slave-address on the bus. */ + rc = i2c_pnx_start(addr, alg_data); + if (rc < 0) + break; + + /* Wait for completion */ + wait_for_completion(&alg_data->mif.complete); + + if (!(rc = alg_data->mif.ret)) + completed++; + dev_dbg(&alg_data->adapter.dev, + "%s(): Complete, return code = %d.\n", + __func__, rc); + + /* Clear TDI and AFI bits in case they are set. */ + if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_tdi) { + dev_dbg(&alg_data->adapter.dev, + "%s: TDI still set... clearing now.\n", + alg_data->adapter.name); + iowrite32(stat, I2C_REG_STS(alg_data)); + } + if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_afi) { + dev_dbg(&alg_data->adapter.dev, + "%s: AFI still set... clearing now.\n", + alg_data->adapter.name); + iowrite32(stat, I2C_REG_STS(alg_data)); + } + } + + bus_reset_if_active(alg_data); + + /* Cleanup to be sure... */ + alg_data->mif.buf = NULL; + alg_data->mif.len = 0; + alg_data->mif.order = 0; + + dev_dbg(&alg_data->adapter.dev, "%s(): exiting, stat = %x\n", + __func__, ioread32(I2C_REG_STS(alg_data))); + + if (completed != num) + return ((rc < 0) ? rc : -EREMOTEIO); + + return num; +} + +static u32 i2c_pnx_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm pnx_algorithm = { + .master_xfer = i2c_pnx_xfer, + .functionality = i2c_pnx_func, +}; + +static int i2c_pnx_controller_suspend(struct device *dev) +{ + struct i2c_pnx_algo_data *alg_data = dev_get_drvdata(dev); + + clk_disable_unprepare(alg_data->clk); + + return 0; +} + +static int i2c_pnx_controller_resume(struct device *dev) +{ + struct i2c_pnx_algo_data *alg_data = dev_get_drvdata(dev); + + return clk_prepare_enable(alg_data->clk); +} + +static DEFINE_SIMPLE_DEV_PM_OPS(i2c_pnx_pm, + i2c_pnx_controller_suspend, + i2c_pnx_controller_resume); + +static int i2c_pnx_probe(struct platform_device *pdev) +{ + unsigned long tmp; + int ret = 0; + struct i2c_pnx_algo_data *alg_data; + unsigned long freq; + struct resource *res; + u32 speed = I2C_PNX_SPEED_KHZ_DEFAULT * 1000; + + alg_data = devm_kzalloc(&pdev->dev, sizeof(*alg_data), GFP_KERNEL); + if (!alg_data) + return -ENOMEM; + + platform_set_drvdata(pdev, alg_data); + + alg_data->adapter.dev.parent = &pdev->dev; + alg_data->adapter.algo = &pnx_algorithm; + alg_data->adapter.algo_data = alg_data; + alg_data->adapter.nr = pdev->id; + + alg_data->timeout = I2C_PNX_TIMEOUT_DEFAULT; +#ifdef CONFIG_OF + alg_data->adapter.dev.of_node = of_node_get(pdev->dev.of_node); + if (pdev->dev.of_node) { + of_property_read_u32(pdev->dev.of_node, "clock-frequency", + &speed); + /* + * At this point, it is planned to add an OF timeout property. + * As soon as there is a consensus about how to call and handle + * this, sth. like the following can be put here: + * + * of_property_read_u32(pdev->dev.of_node, "timeout", + * &alg_data->timeout); + */ + } +#endif + alg_data->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(alg_data->clk)) + return PTR_ERR(alg_data->clk); + + timer_setup(&alg_data->mif.timer, i2c_pnx_timeout, 0); + + snprintf(alg_data->adapter.name, sizeof(alg_data->adapter.name), + "%s", pdev->name); + + /* Register I/O resource */ + alg_data->ioaddr = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(alg_data->ioaddr)) + return PTR_ERR(alg_data->ioaddr); + + ret = clk_prepare_enable(alg_data->clk); + if (ret) + return ret; + + freq = clk_get_rate(alg_data->clk); + + /* + * Clock Divisor High This value is the number of system clocks + * the serial clock (SCL) will be high. + * For example, if the system clock period is 50 ns and the maximum + * desired serial period is 10000 ns (100 kHz), then CLKHI would be + * set to 0.5*(f_sys/f_i2c)-2=0.5*(20e6/100e3)-2=98. The actual value + * programmed into CLKHI will vary from this slightly due to + * variations in the output pad's rise and fall times as well as + * the deglitching filter length. + */ + + tmp = (freq / speed) / 2 - 2; + if (tmp > 0x3FF) + tmp = 0x3FF; + iowrite32(tmp, I2C_REG_CKH(alg_data)); + iowrite32(tmp, I2C_REG_CKL(alg_data)); + + iowrite32(mcntrl_reset, I2C_REG_CTL(alg_data)); + if (wait_reset(alg_data)) { + ret = -ENODEV; + goto out_clock; + } + init_completion(&alg_data->mif.complete); + + alg_data->irq = platform_get_irq(pdev, 0); + if (alg_data->irq < 0) { + ret = alg_data->irq; + goto out_clock; + } + ret = devm_request_irq(&pdev->dev, alg_data->irq, i2c_pnx_interrupt, + 0, pdev->name, alg_data); + if (ret) + goto out_clock; + + /* Register this adapter with the I2C subsystem */ + ret = i2c_add_numbered_adapter(&alg_data->adapter); + if (ret < 0) + goto out_clock; + + dev_dbg(&pdev->dev, "%s: Master at %pap, irq %d.\n", + alg_data->adapter.name, &res->start, alg_data->irq); + + return 0; + +out_clock: + clk_disable_unprepare(alg_data->clk); + return ret; +} + +static void i2c_pnx_remove(struct platform_device *pdev) +{ + struct i2c_pnx_algo_data *alg_data = platform_get_drvdata(pdev); + + i2c_del_adapter(&alg_data->adapter); + clk_disable_unprepare(alg_data->clk); +} + +#ifdef CONFIG_OF +static const struct of_device_id i2c_pnx_of_match[] = { + { .compatible = "nxp,pnx-i2c" }, + { }, +}; +MODULE_DEVICE_TABLE(of, i2c_pnx_of_match); +#endif + +static struct platform_driver i2c_pnx_driver = { + .driver = { + .name = "pnx-i2c", + .of_match_table = of_match_ptr(i2c_pnx_of_match), + .pm = pm_sleep_ptr(&i2c_pnx_pm), + }, + .probe = i2c_pnx_probe, + .remove_new = i2c_pnx_remove, +}; + +static int __init i2c_adap_pnx_init(void) +{ + return platform_driver_register(&i2c_pnx_driver); +} + +static void __exit i2c_adap_pnx_exit(void) +{ + platform_driver_unregister(&i2c_pnx_driver); +} + +MODULE_AUTHOR("Vitaly Wool"); +MODULE_AUTHOR("Dennis Kovalev <source@mvista.com>"); +MODULE_DESCRIPTION("I2C driver for Philips IP3204-based I2C busses"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:pnx-i2c"); + +/* We need to make sure I2C is initialized before USB */ +subsys_initcall(i2c_adap_pnx_init); +module_exit(i2c_adap_pnx_exit); diff --git a/drivers/i2c/busses/i2c-powermac.c b/drivers/i2c/busses/i2c-powermac.c new file mode 100644 index 000000000..4996a628f --- /dev/null +++ b/drivers/i2c/busses/i2c-powermac.c @@ -0,0 +1,449 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + i2c Support for Apple SMU Controller + + Copyright (c) 2005 Benjamin Herrenschmidt, IBM Corp. + <benh@kernel.crashing.org> + + +*/ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/i2c.h> +#include <linux/device.h> +#include <linux/platform_device.h> +#include <linux/of_irq.h> + +#include <asm/pmac_low_i2c.h> + +MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); +MODULE_DESCRIPTION("I2C driver for Apple PowerMac"); +MODULE_LICENSE("GPL"); + +/* + * SMBUS-type transfer entrypoint + */ +static s32 i2c_powermac_smbus_xfer( struct i2c_adapter* adap, + u16 addr, + unsigned short flags, + char read_write, + u8 command, + int size, + union i2c_smbus_data* data) +{ + struct pmac_i2c_bus *bus = i2c_get_adapdata(adap); + int rc = 0; + int read = (read_write == I2C_SMBUS_READ); + int addrdir = (addr << 1) | read; + int mode, subsize, len; + u32 subaddr; + u8 *buf; + u8 local[2]; + + if (size == I2C_SMBUS_QUICK || size == I2C_SMBUS_BYTE) { + mode = pmac_i2c_mode_std; + subsize = 0; + subaddr = 0; + } else { + mode = read ? pmac_i2c_mode_combined : pmac_i2c_mode_stdsub; + subsize = 1; + subaddr = command; + } + + switch (size) { + case I2C_SMBUS_QUICK: + buf = NULL; + len = 0; + break; + case I2C_SMBUS_BYTE: + case I2C_SMBUS_BYTE_DATA: + buf = &data->byte; + len = 1; + break; + case I2C_SMBUS_WORD_DATA: + if (!read) { + local[0] = data->word & 0xff; + local[1] = (data->word >> 8) & 0xff; + } + buf = local; + len = 2; + break; + + /* Note that these are broken vs. the expected smbus API where + * on reads, the length is actually returned from the function, + * but I think the current API makes no sense and I don't want + * any driver that I haven't verified for correctness to go + * anywhere near a pmac i2c bus anyway ... + */ + case I2C_SMBUS_BLOCK_DATA: + buf = data->block; + len = data->block[0] + 1; + break; + case I2C_SMBUS_I2C_BLOCK_DATA: + buf = &data->block[1]; + len = data->block[0]; + break; + + default: + return -EINVAL; + } + + rc = pmac_i2c_open(bus, 0); + if (rc) { + dev_err(&adap->dev, "Failed to open I2C, err %d\n", rc); + return rc; + } + + rc = pmac_i2c_setmode(bus, mode); + if (rc) { + dev_err(&adap->dev, "Failed to set I2C mode %d, err %d\n", + mode, rc); + goto bail; + } + + rc = pmac_i2c_xfer(bus, addrdir, subsize, subaddr, buf, len); + if (rc) { + if (rc == -ENXIO) + dev_dbg(&adap->dev, + "I2C transfer at 0x%02x failed, size %d, " + "err %d\n", addrdir >> 1, size, rc); + else + dev_err(&adap->dev, + "I2C transfer at 0x%02x failed, size %d, " + "err %d\n", addrdir >> 1, size, rc); + goto bail; + } + + if (size == I2C_SMBUS_WORD_DATA && read) { + data->word = ((u16)local[1]) << 8; + data->word |= local[0]; + } + + bail: + pmac_i2c_close(bus); + return rc; +} + +/* + * Generic i2c master transfer entrypoint. This driver only support single + * messages (for "lame i2c" transfers). Anything else should use the smbus + * entry point + */ +static int i2c_powermac_master_xfer( struct i2c_adapter *adap, + struct i2c_msg *msgs, + int num) +{ + struct pmac_i2c_bus *bus = i2c_get_adapdata(adap); + int rc = 0; + int addrdir; + + if (msgs->flags & I2C_M_TEN) + return -EINVAL; + addrdir = i2c_8bit_addr_from_msg(msgs); + + rc = pmac_i2c_open(bus, 0); + if (rc) { + dev_err(&adap->dev, "Failed to open I2C, err %d\n", rc); + return rc; + } + rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std); + if (rc) { + dev_err(&adap->dev, "Failed to set I2C mode %d, err %d\n", + pmac_i2c_mode_std, rc); + goto bail; + } + rc = pmac_i2c_xfer(bus, addrdir, 0, 0, msgs->buf, msgs->len); + if (rc < 0) { + if (rc == -ENXIO) + dev_dbg(&adap->dev, "I2C %s 0x%02x failed, err %d\n", + addrdir & 1 ? "read from" : "write to", + addrdir >> 1, rc); + else + dev_err(&adap->dev, "I2C %s 0x%02x failed, err %d\n", + addrdir & 1 ? "read from" : "write to", + addrdir >> 1, rc); + } + bail: + pmac_i2c_close(bus); + return rc < 0 ? rc : 1; +} + +static u32 i2c_powermac_func(struct i2c_adapter * adapter) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_I2C; +} + +/* For now, we only handle smbus */ +static const struct i2c_algorithm i2c_powermac_algorithm = { + .smbus_xfer = i2c_powermac_smbus_xfer, + .master_xfer = i2c_powermac_master_xfer, + .functionality = i2c_powermac_func, +}; + +static const struct i2c_adapter_quirks i2c_powermac_quirks = { + .max_num_msgs = 1, +}; + +static void i2c_powermac_remove(struct platform_device *dev) +{ + struct i2c_adapter *adapter = platform_get_drvdata(dev); + + i2c_del_adapter(adapter); + memset(adapter, 0, sizeof(*adapter)); +} + +static u32 i2c_powermac_get_addr(struct i2c_adapter *adap, + struct pmac_i2c_bus *bus, + struct device_node *node) +{ + u32 prop; + int ret; + + /* First check for valid "reg" */ + ret = of_property_read_u32(node, "reg", &prop); + if (ret == 0) + return (prop & 0xff) >> 1; + + /* Then check old-style "i2c-address" */ + ret = of_property_read_u32(node, "i2c-address", &prop); + if (ret == 0) + return (prop & 0xff) >> 1; + + /* Now handle some devices with missing "reg" properties */ + if (of_node_name_eq(node, "cereal")) + return 0x60; + else if (of_node_name_eq(node, "deq")) + return 0x34; + + dev_warn(&adap->dev, "No i2c address for %pOF\n", node); + + return 0xffffffff; +} + +static void i2c_powermac_create_one(struct i2c_adapter *adap, + const char *type, + u32 addr) +{ + struct i2c_board_info info = {}; + struct i2c_client *newdev; + + strncpy(info.type, type, sizeof(info.type)); + info.addr = addr; + newdev = i2c_new_client_device(adap, &info); + if (IS_ERR(newdev)) + dev_err(&adap->dev, + "i2c-powermac: Failure to register missing %s\n", + type); +} + +static void i2c_powermac_add_missing(struct i2c_adapter *adap, + struct pmac_i2c_bus *bus, + bool found_onyx) +{ + struct device_node *busnode = pmac_i2c_get_bus_node(bus); + int rc; + + /* Check for the onyx audio codec */ +#define ONYX_REG_CONTROL 67 + if (of_device_is_compatible(busnode, "k2-i2c") && !found_onyx) { + union i2c_smbus_data data; + + rc = i2c_smbus_xfer(adap, 0x46, 0, I2C_SMBUS_READ, + ONYX_REG_CONTROL, I2C_SMBUS_BYTE_DATA, + &data); + if (rc >= 0) + i2c_powermac_create_one(adap, "MAC,pcm3052", 0x46); + + rc = i2c_smbus_xfer(adap, 0x47, 0, I2C_SMBUS_READ, + ONYX_REG_CONTROL, I2C_SMBUS_BYTE_DATA, + &data); + if (rc >= 0) + i2c_powermac_create_one(adap, "MAC,pcm3052", 0x47); + } +} + +static bool i2c_powermac_get_type(struct i2c_adapter *adap, + struct device_node *node, + u32 addr, char *type, int type_size) +{ + char tmp[16]; + + /* + * Note: we do _NOT_ want the standard i2c drivers to match with any of + * our powermac stuff unless they have been specifically modified to + * handle it on a case by case basis. For example, for thermal control, + * things like lm75 etc... shall match with their corresponding + * windfarm drivers, _NOT_ the generic ones, so we force a prefix of + * 'MAC', onto the modalias to make that happen + */ + + /* First try proper modalias */ + if (of_alias_from_compatible(node, tmp, sizeof(tmp)) >= 0) { + snprintf(type, type_size, "MAC,%s", tmp); + return true; + } + + /* Now look for known workarounds */ + if (of_node_name_eq(node, "deq")) { + /* Apple uses address 0x34 for TAS3001 and 0x35 for TAS3004 */ + if (addr == 0x34) { + snprintf(type, type_size, "MAC,tas3001"); + return true; + } else if (addr == 0x35) { + snprintf(type, type_size, "MAC,tas3004"); + return true; + } + } + + dev_err(&adap->dev, "i2c-powermac: modalias failure on %pOF\n", node); + return false; +} + +static void i2c_powermac_register_devices(struct i2c_adapter *adap, + struct pmac_i2c_bus *bus) +{ + struct i2c_client *newdev; + struct device_node *node; + bool found_onyx = false; + + /* + * In some cases we end up with the via-pmu node itself, in this + * case we skip this function completely as the device-tree will + * not contain anything useful. + */ + if (of_node_name_eq(adap->dev.of_node, "via-pmu")) + return; + + for_each_child_of_node(adap->dev.of_node, node) { + struct i2c_board_info info = {}; + u32 addr; + + /* Get address & channel */ + addr = i2c_powermac_get_addr(adap, bus, node); + if (addr == 0xffffffff) + continue; + + /* Multibus setup, check channel */ + if (!pmac_i2c_match_adapter(node, adap)) + continue; + + dev_dbg(&adap->dev, "i2c-powermac: register %pOF\n", node); + + /* + * Keep track of some device existence to handle + * workarounds later. + */ + if (of_device_is_compatible(node, "pcm3052")) + found_onyx = true; + + /* Make up a modalias */ + if (!i2c_powermac_get_type(adap, node, addr, + info.type, sizeof(info.type))) { + continue; + } + + /* Fill out the rest of the info structure */ + info.addr = addr; + info.irq = irq_of_parse_and_map(node, 0); + info.of_node = of_node_get(node); + + newdev = i2c_new_client_device(adap, &info); + if (IS_ERR(newdev)) { + dev_err(&adap->dev, "i2c-powermac: Failure to register" + " %pOF\n", node); + of_node_put(node); + /* We do not dispose of the interrupt mapping on + * purpose. It's not necessary (interrupt cannot be + * re-used) and somebody else might have grabbed it + * via direct DT lookup so let's not bother + */ + continue; + } + } + + /* Additional workarounds */ + i2c_powermac_add_missing(adap, bus, found_onyx); +} + +static int i2c_powermac_probe(struct platform_device *dev) +{ + struct pmac_i2c_bus *bus = dev_get_platdata(&dev->dev); + struct device_node *parent; + struct i2c_adapter *adapter; + int rc; + + if (bus == NULL) + return -EINVAL; + adapter = pmac_i2c_get_adapter(bus); + + /* Ok, now we need to make up a name for the interface that will + * match what we used to do in the past, that is basically the + * controller's parent device node for keywest. PMU didn't have a + * naming convention and SMU has a different one + */ + switch(pmac_i2c_get_type(bus)) { + case pmac_i2c_bus_keywest: + parent = of_get_parent(pmac_i2c_get_controller(bus)); + if (parent == NULL) + return -EINVAL; + snprintf(adapter->name, sizeof(adapter->name), "%pOFn %d", + parent, + pmac_i2c_get_channel(bus)); + of_node_put(parent); + break; + case pmac_i2c_bus_pmu: + snprintf(adapter->name, sizeof(adapter->name), "pmu %d", + pmac_i2c_get_channel(bus)); + break; + case pmac_i2c_bus_smu: + /* This is not what we used to do but I'm fixing drivers at + * the same time as this change + */ + snprintf(adapter->name, sizeof(adapter->name), "smu %d", + pmac_i2c_get_channel(bus)); + break; + default: + return -EINVAL; + } + + platform_set_drvdata(dev, adapter); + adapter->algo = &i2c_powermac_algorithm; + adapter->quirks = &i2c_powermac_quirks; + i2c_set_adapdata(adapter, bus); + adapter->dev.parent = &dev->dev; + + /* Clear of_node to skip automatic registration of i2c child nodes */ + adapter->dev.of_node = NULL; + rc = i2c_add_adapter(adapter); + if (rc) { + printk(KERN_ERR "i2c-powermac: Adapter %s registration " + "failed\n", adapter->name); + memset(adapter, 0, sizeof(*adapter)); + return rc; + } + + printk(KERN_INFO "PowerMac i2c bus %s registered\n", adapter->name); + + /* Use custom child registration due to Apple device-tree funkyness */ + adapter->dev.of_node = dev->dev.of_node; + i2c_powermac_register_devices(adapter, bus); + + return 0; +} + +static struct platform_driver i2c_powermac_driver = { + .probe = i2c_powermac_probe, + .remove_new = i2c_powermac_remove, + .driver = { + .name = "i2c-powermac", + .bus = &platform_bus_type, + }, +}; + +module_platform_driver(i2c_powermac_driver); + +MODULE_ALIAS("platform:i2c-powermac"); diff --git a/drivers/i2c/busses/i2c-pxa-pci.c b/drivers/i2c/busses/i2c-pxa-pci.c new file mode 100644 index 000000000..08b3229c4 --- /dev/null +++ b/drivers/i2c/busses/i2c-pxa-pci.c @@ -0,0 +1,149 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * CE4100 PCI-I2C glue code for PXA's driver + * Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> + * + * The CE4100's I2C device is more or less the same one as found on PXA. + * It does not support slave mode, the register slightly moved. This PCI + * device provides three bars, every contains a single I2C controller. + */ +#include <linux/init.h> +#include <linux/pci.h> +#include <linux/platform_device.h> +#include <linux/platform_data/i2c-pxa.h> +#include <linux/of.h> +#include <linux/of_address.h> + +#define CE4100_PCI_I2C_DEVS 3 + +struct ce4100_devices { + struct platform_device *pdev[CE4100_PCI_I2C_DEVS]; +}; + +static struct platform_device *add_i2c_device(struct pci_dev *dev, int bar) +{ + struct platform_device *pdev; + struct i2c_pxa_platform_data pdata; + struct resource res[2]; + struct device_node *child; + static int devnum; + int ret; + + memset(&pdata, 0, sizeof(struct i2c_pxa_platform_data)); + memset(&res, 0, sizeof(res)); + + res[0].flags = IORESOURCE_MEM; + res[0].start = pci_resource_start(dev, bar); + res[0].end = pci_resource_end(dev, bar); + + res[1].flags = IORESOURCE_IRQ; + res[1].start = dev->irq; + res[1].end = dev->irq; + + for_each_child_of_node(dev->dev.of_node, child) { + const void *prop; + struct resource r; + int ret; + + ret = of_address_to_resource(child, 0, &r); + if (ret < 0) + continue; + if (r.start != res[0].start) + continue; + if (r.end != res[0].end) + continue; + if (r.flags != res[0].flags) + continue; + + prop = of_get_property(child, "fast-mode", NULL); + if (prop) + pdata.fast_mode = 1; + + break; + } + + if (!child) { + dev_err(&dev->dev, "failed to match a DT node for bar %d.\n", + bar); + ret = -EINVAL; + goto out; + } + + pdev = platform_device_alloc("ce4100-i2c", devnum); + if (!pdev) { + of_node_put(child); + ret = -ENOMEM; + goto out; + } + pdev->dev.parent = &dev->dev; + pdev->dev.of_node = child; + + ret = platform_device_add_resources(pdev, res, ARRAY_SIZE(res)); + if (ret) + goto err; + + ret = platform_device_add_data(pdev, &pdata, sizeof(pdata)); + if (ret) + goto err; + + ret = platform_device_add(pdev); + if (ret) + goto err; + devnum++; + return pdev; +err: + platform_device_put(pdev); +out: + return ERR_PTR(ret); +} + +static int ce4100_i2c_probe(struct pci_dev *dev, + const struct pci_device_id *ent) +{ + int ret; + int i; + struct ce4100_devices *sds; + + ret = pcim_enable_device(dev); + if (ret) + return ret; + + if (!dev->dev.of_node) { + dev_err(&dev->dev, "Missing device tree node.\n"); + return -EINVAL; + } + sds = kzalloc(sizeof(*sds), GFP_KERNEL); + if (!sds) + return -ENOMEM; + + for (i = 0; i < ARRAY_SIZE(sds->pdev); i++) { + sds->pdev[i] = add_i2c_device(dev, i); + if (IS_ERR(sds->pdev[i])) { + ret = PTR_ERR(sds->pdev[i]); + while (--i >= 0) + platform_device_unregister(sds->pdev[i]); + goto err_dev_add; + } + } + pci_set_drvdata(dev, sds); + return 0; + +err_dev_add: + kfree(sds); + return ret; +} + +static const struct pci_device_id ce4100_i2c_devices[] = { + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2e68)}, + { }, +}; + +static struct pci_driver ce4100_i2c_driver = { + .driver = { + .suppress_bind_attrs = true, + }, + .name = "ce4100_i2c", + .id_table = ce4100_i2c_devices, + .probe = ce4100_i2c_probe, +}; +builtin_pci_driver(ce4100_i2c_driver); diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c new file mode 100644 index 000000000..3bd406470 --- /dev/null +++ b/drivers/i2c/busses/i2c-pxa.c @@ -0,0 +1,1600 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * i2c_adap_pxa.c + * + * I2C adapter for the PXA I2C bus access. + * + * Copyright (C) 2002 Intrinsyc Software Inc. + * Copyright (C) 2004-2005 Deep Blue Solutions Ltd. + * + * History: + * Apr 2002: Initial version [CS] + * Jun 2002: Properly separated algo/adap [FB] + * Jan 2003: Fixed several bugs concerning interrupt handling [Kai-Uwe Bloem] + * Jan 2003: added limited signal handling [Kai-Uwe Bloem] + * Sep 2004: Major rework to ensure efficient bus handling [RMK] + * Dec 2004: Added support for PXA27x and slave device probing [Liam Girdwood] + * Feb 2005: Rework slave mode handling [RMK] + */ +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> +#include <linux/platform_data/i2c-pxa.h> +#include <linux/slab.h> + +/* I2C register field definitions */ +#define IBMR_SDAS (1 << 0) +#define IBMR_SCLS (1 << 1) + +#define ICR_START (1 << 0) /* start bit */ +#define ICR_STOP (1 << 1) /* stop bit */ +#define ICR_ACKNAK (1 << 2) /* send ACK(0) or NAK(1) */ +#define ICR_TB (1 << 3) /* transfer byte bit */ +#define ICR_MA (1 << 4) /* master abort */ +#define ICR_SCLE (1 << 5) /* master clock enable */ +#define ICR_IUE (1 << 6) /* unit enable */ +#define ICR_GCD (1 << 7) /* general call disable */ +#define ICR_ITEIE (1 << 8) /* enable tx interrupts */ +#define ICR_IRFIE (1 << 9) /* enable rx interrupts */ +#define ICR_BEIE (1 << 10) /* enable bus error ints */ +#define ICR_SSDIE (1 << 11) /* slave STOP detected int enable */ +#define ICR_ALDIE (1 << 12) /* enable arbitration interrupt */ +#define ICR_SADIE (1 << 13) /* slave address detected int enable */ +#define ICR_UR (1 << 14) /* unit reset */ +#define ICR_FM (1 << 15) /* fast mode */ +#define ICR_HS (1 << 16) /* High Speed mode */ +#define ICR_A3700_FM (1 << 16) /* fast mode for armada-3700 */ +#define ICR_A3700_HS (1 << 17) /* high speed mode for armada-3700 */ +#define ICR_GPIOEN (1 << 19) /* enable GPIO mode for SCL in HS */ + +#define ISR_RWM (1 << 0) /* read/write mode */ +#define ISR_ACKNAK (1 << 1) /* ack/nak status */ +#define ISR_UB (1 << 2) /* unit busy */ +#define ISR_IBB (1 << 3) /* bus busy */ +#define ISR_SSD (1 << 4) /* slave stop detected */ +#define ISR_ALD (1 << 5) /* arbitration loss detected */ +#define ISR_ITE (1 << 6) /* tx buffer empty */ +#define ISR_IRF (1 << 7) /* rx buffer full */ +#define ISR_GCAD (1 << 8) /* general call address detected */ +#define ISR_SAD (1 << 9) /* slave address detected */ +#define ISR_BED (1 << 10) /* bus error no ACK/NAK */ + +#define ILCR_SLV_SHIFT 0 +#define ILCR_SLV_MASK (0x1FF << ILCR_SLV_SHIFT) +#define ILCR_FLV_SHIFT 9 +#define ILCR_FLV_MASK (0x1FF << ILCR_FLV_SHIFT) +#define ILCR_HLVL_SHIFT 18 +#define ILCR_HLVL_MASK (0x1FF << ILCR_HLVL_SHIFT) +#define ILCR_HLVH_SHIFT 27 +#define ILCR_HLVH_MASK (0x1F << ILCR_HLVH_SHIFT) + +#define IWCR_CNT_SHIFT 0 +#define IWCR_CNT_MASK (0x1F << IWCR_CNT_SHIFT) +#define IWCR_HS_CNT1_SHIFT 5 +#define IWCR_HS_CNT1_MASK (0x1F << IWCR_HS_CNT1_SHIFT) +#define IWCR_HS_CNT2_SHIFT 10 +#define IWCR_HS_CNT2_MASK (0x1F << IWCR_HS_CNT2_SHIFT) + +/* need a longer timeout if we're dealing with the fact we may well be + * looking at a multi-master environment + */ +#define DEF_TIMEOUT 32 + +#define NO_SLAVE (-ENXIO) +#define BUS_ERROR (-EREMOTEIO) +#define XFER_NAKED (-ECONNREFUSED) +#define I2C_RETRY (-2000) /* an error has occurred retry transmit */ + +/* ICR initialize bit values + * + * 15 FM 0 (100 kHz operation) + * 14 UR 0 (No unit reset) + * 13 SADIE 0 (Disables the unit from interrupting on slave addresses + * matching its slave address) + * 12 ALDIE 0 (Disables the unit from interrupt when it loses arbitration + * in master mode) + * 11 SSDIE 0 (Disables interrupts from a slave stop detected, in slave mode) + * 10 BEIE 1 (Enable interrupts from detected bus errors, no ACK sent) + * 9 IRFIE 1 (Enable interrupts from full buffer received) + * 8 ITEIE 1 (Enables the I2C unit to interrupt when transmit buffer empty) + * 7 GCD 1 (Disables i2c unit response to general call messages as a slave) + * 6 IUE 0 (Disable unit until we change settings) + * 5 SCLE 1 (Enables the i2c clock output for master mode (drives SCL) + * 4 MA 0 (Only send stop with the ICR stop bit) + * 3 TB 0 (We are not transmitting a byte initially) + * 2 ACKNAK 0 (Send an ACK after the unit receives a byte) + * 1 STOP 0 (Do not send a STOP) + * 0 START 0 (Do not send a START) + */ +#define I2C_ICR_INIT (ICR_BEIE | ICR_IRFIE | ICR_ITEIE | ICR_GCD | ICR_SCLE) + +/* I2C status register init values + * + * 10 BED 1 (Clear bus error detected) + * 9 SAD 1 (Clear slave address detected) + * 7 IRF 1 (Clear IDBR Receive Full) + * 6 ITE 1 (Clear IDBR Transmit Empty) + * 5 ALD 1 (Clear Arbitration Loss Detected) + * 4 SSD 1 (Clear Slave Stop Detected) + */ +#define I2C_ISR_INIT 0x7FF /* status register init */ + +struct pxa_reg_layout { + u32 ibmr; + u32 idbr; + u32 icr; + u32 isr; + u32 isar; + u32 ilcr; + u32 iwcr; + u32 fm; + u32 hs; +}; + +enum pxa_i2c_types { + REGS_PXA2XX, + REGS_PXA3XX, + REGS_CE4100, + REGS_PXA910, + REGS_A3700, +}; + +/* I2C register layout definitions */ +static struct pxa_reg_layout pxa_reg_layout[] = { + [REGS_PXA2XX] = { + .ibmr = 0x00, + .idbr = 0x08, + .icr = 0x10, + .isr = 0x18, + .isar = 0x20, + .fm = ICR_FM, + .hs = ICR_HS, + }, + [REGS_PXA3XX] = { + .ibmr = 0x00, + .idbr = 0x04, + .icr = 0x08, + .isr = 0x0c, + .isar = 0x10, + .fm = ICR_FM, + .hs = ICR_HS, + }, + [REGS_CE4100] = { + .ibmr = 0x14, + .idbr = 0x0c, + .icr = 0x00, + .isr = 0x04, + /* no isar register */ + .fm = ICR_FM, + .hs = ICR_HS, + }, + [REGS_PXA910] = { + .ibmr = 0x00, + .idbr = 0x08, + .icr = 0x10, + .isr = 0x18, + .isar = 0x20, + .ilcr = 0x28, + .iwcr = 0x30, + .fm = ICR_FM, + .hs = ICR_HS, + }, + [REGS_A3700] = { + .ibmr = 0x00, + .idbr = 0x04, + .icr = 0x08, + .isr = 0x0c, + .isar = 0x10, + .fm = ICR_A3700_FM, + .hs = ICR_A3700_HS, + }, +}; + +static const struct of_device_id i2c_pxa_dt_ids[] = { + { .compatible = "mrvl,pxa-i2c", .data = (void *)REGS_PXA2XX }, + { .compatible = "mrvl,pwri2c", .data = (void *)REGS_PXA3XX }, + { .compatible = "mrvl,mmp-twsi", .data = (void *)REGS_PXA910 }, + { .compatible = "marvell,armada-3700-i2c", .data = (void *)REGS_A3700 }, + {} +}; +MODULE_DEVICE_TABLE(of, i2c_pxa_dt_ids); + +static const struct platform_device_id i2c_pxa_id_table[] = { + { "pxa2xx-i2c", REGS_PXA2XX }, + { "pxa3xx-pwri2c", REGS_PXA3XX }, + { "ce4100-i2c", REGS_CE4100 }, + { "pxa910-i2c", REGS_PXA910 }, + { "armada-3700-i2c", REGS_A3700 }, + { }, +}; +MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table); + +struct pxa_i2c { + spinlock_t lock; + wait_queue_head_t wait; + struct i2c_msg *msg; + unsigned int msg_num; + unsigned int msg_idx; + unsigned int msg_ptr; + unsigned int slave_addr; + unsigned int req_slave_addr; + + struct i2c_adapter adap; + struct clk *clk; +#ifdef CONFIG_I2C_PXA_SLAVE + struct i2c_client *slave; +#endif + + unsigned int irqlogidx; + u32 isrlog[32]; + u32 icrlog[32]; + + void __iomem *reg_base; + void __iomem *reg_ibmr; + void __iomem *reg_idbr; + void __iomem *reg_icr; + void __iomem *reg_isr; + void __iomem *reg_isar; + void __iomem *reg_ilcr; + void __iomem *reg_iwcr; + + unsigned long iobase; + unsigned long iosize; + + int irq; + unsigned int use_pio :1; + unsigned int fast_mode :1; + unsigned int high_mode:1; + unsigned char master_code; + unsigned long rate; + bool highmode_enter; + u32 fm_mask; + u32 hs_mask; + + struct i2c_bus_recovery_info recovery; + struct pinctrl *pinctrl; + struct pinctrl_state *pinctrl_default; + struct pinctrl_state *pinctrl_recovery; +}; + +#define _IBMR(i2c) ((i2c)->reg_ibmr) +#define _IDBR(i2c) ((i2c)->reg_idbr) +#define _ICR(i2c) ((i2c)->reg_icr) +#define _ISR(i2c) ((i2c)->reg_isr) +#define _ISAR(i2c) ((i2c)->reg_isar) +#define _ILCR(i2c) ((i2c)->reg_ilcr) +#define _IWCR(i2c) ((i2c)->reg_iwcr) + +/* + * I2C Slave mode address + */ +#define I2C_PXA_SLAVE_ADDR 0x1 + +#ifdef DEBUG + +struct bits { + u32 mask; + const char *set; + const char *unset; +}; +#define PXA_BIT(m, s, u) { .mask = m, .set = s, .unset = u } + +static inline void +decode_bits(const char *prefix, const struct bits *bits, int num, u32 val) +{ + printk("%s %08x:", prefix, val); + while (num--) { + const char *str = val & bits->mask ? bits->set : bits->unset; + if (str) + pr_cont(" %s", str); + bits++; + } + pr_cont("\n"); +} + +static const struct bits isr_bits[] = { + PXA_BIT(ISR_RWM, "RX", "TX"), + PXA_BIT(ISR_ACKNAK, "NAK", "ACK"), + PXA_BIT(ISR_UB, "Bsy", "Rdy"), + PXA_BIT(ISR_IBB, "BusBsy", "BusRdy"), + PXA_BIT(ISR_SSD, "SlaveStop", NULL), + PXA_BIT(ISR_ALD, "ALD", NULL), + PXA_BIT(ISR_ITE, "TxEmpty", NULL), + PXA_BIT(ISR_IRF, "RxFull", NULL), + PXA_BIT(ISR_GCAD, "GenCall", NULL), + PXA_BIT(ISR_SAD, "SlaveAddr", NULL), + PXA_BIT(ISR_BED, "BusErr", NULL), +}; + +static void decode_ISR(unsigned int val) +{ + decode_bits(KERN_DEBUG "ISR", isr_bits, ARRAY_SIZE(isr_bits), val); +} + +static const struct bits icr_bits[] = { + PXA_BIT(ICR_START, "START", NULL), + PXA_BIT(ICR_STOP, "STOP", NULL), + PXA_BIT(ICR_ACKNAK, "ACKNAK", NULL), + PXA_BIT(ICR_TB, "TB", NULL), + PXA_BIT(ICR_MA, "MA", NULL), + PXA_BIT(ICR_SCLE, "SCLE", "scle"), + PXA_BIT(ICR_IUE, "IUE", "iue"), + PXA_BIT(ICR_GCD, "GCD", NULL), + PXA_BIT(ICR_ITEIE, "ITEIE", NULL), + PXA_BIT(ICR_IRFIE, "IRFIE", NULL), + PXA_BIT(ICR_BEIE, "BEIE", NULL), + PXA_BIT(ICR_SSDIE, "SSDIE", NULL), + PXA_BIT(ICR_ALDIE, "ALDIE", NULL), + PXA_BIT(ICR_SADIE, "SADIE", NULL), + PXA_BIT(ICR_UR, "UR", "ur"), +}; + +#ifdef CONFIG_I2C_PXA_SLAVE +static void decode_ICR(unsigned int val) +{ + decode_bits(KERN_DEBUG "ICR", icr_bits, ARRAY_SIZE(icr_bits), val); +} +#endif + +static unsigned int i2c_debug = DEBUG; + +static void i2c_pxa_show_state(struct pxa_i2c *i2c, int lno, const char *fname) +{ + dev_dbg(&i2c->adap.dev, "state:%s:%d: ISR=%08x, ICR=%08x, IBMR=%02x\n", fname, lno, + readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c))); +} + +#define show_state(i2c) i2c_pxa_show_state(i2c, __LINE__, __func__) + +static void i2c_pxa_scream_blue_murder(struct pxa_i2c *i2c, const char *why) +{ + unsigned int i; + struct device *dev = &i2c->adap.dev; + + dev_err(dev, "slave_0x%x error: %s\n", + i2c->req_slave_addr >> 1, why); + dev_err(dev, "msg_num: %d msg_idx: %d msg_ptr: %d\n", + i2c->msg_num, i2c->msg_idx, i2c->msg_ptr); + dev_err(dev, "IBMR: %08x IDBR: %08x ICR: %08x ISR: %08x\n", + readl(_IBMR(i2c)), readl(_IDBR(i2c)), readl(_ICR(i2c)), + readl(_ISR(i2c))); + dev_err(dev, "log:"); + for (i = 0; i < i2c->irqlogidx; i++) + pr_cont(" [%03x:%05x]", i2c->isrlog[i], i2c->icrlog[i]); + pr_cont("\n"); +} + +#else /* ifdef DEBUG */ + +#define i2c_debug 0 + +#define show_state(i2c) do { } while (0) +#define decode_ISR(val) do { } while (0) +#define decode_ICR(val) do { } while (0) +#define i2c_pxa_scream_blue_murder(i2c, why) do { } while (0) + +#endif /* ifdef DEBUG / else */ + +static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret); + +static inline int i2c_pxa_is_slavemode(struct pxa_i2c *i2c) +{ + return !(readl(_ICR(i2c)) & ICR_SCLE); +} + +static void i2c_pxa_abort(struct pxa_i2c *i2c) +{ + int i = 250; + + if (i2c_pxa_is_slavemode(i2c)) { + dev_dbg(&i2c->adap.dev, "%s: called in slave mode\n", __func__); + return; + } + + while ((i > 0) && (readl(_IBMR(i2c)) & IBMR_SDAS) == 0) { + unsigned long icr = readl(_ICR(i2c)); + + icr &= ~ICR_START; + icr |= ICR_ACKNAK | ICR_STOP | ICR_TB; + + writel(icr, _ICR(i2c)); + + show_state(i2c); + + mdelay(1); + i --; + } + + writel(readl(_ICR(i2c)) & ~(ICR_MA | ICR_START | ICR_STOP), + _ICR(i2c)); +} + +static int i2c_pxa_wait_bus_not_busy(struct pxa_i2c *i2c) +{ + int timeout = DEF_TIMEOUT; + u32 isr; + + while (1) { + isr = readl(_ISR(i2c)); + if (!(isr & (ISR_IBB | ISR_UB))) + return 0; + + if (isr & ISR_SAD) + timeout += 4; + + if (!timeout--) + break; + + msleep(2); + show_state(i2c); + } + + show_state(i2c); + + return I2C_RETRY; +} + +static int i2c_pxa_wait_master(struct pxa_i2c *i2c) +{ + unsigned long timeout = jiffies + HZ*4; + + while (time_before(jiffies, timeout)) { + if (i2c_debug > 1) + dev_dbg(&i2c->adap.dev, "%s: %ld: ISR=%08x, ICR=%08x, IBMR=%02x\n", + __func__, (long)jiffies, readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c))); + + if (readl(_ISR(i2c)) & ISR_SAD) { + if (i2c_debug > 0) + dev_dbg(&i2c->adap.dev, "%s: Slave detected\n", __func__); + goto out; + } + + /* wait for unit and bus being not busy, and we also do a + * quick check of the i2c lines themselves to ensure they've + * gone high... + */ + if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) == 0 && + readl(_IBMR(i2c)) == (IBMR_SCLS | IBMR_SDAS)) { + if (i2c_debug > 0) + dev_dbg(&i2c->adap.dev, "%s: done\n", __func__); + return 1; + } + + msleep(1); + } + + if (i2c_debug > 0) + dev_dbg(&i2c->adap.dev, "%s: did not free\n", __func__); + out: + return 0; +} + +static int i2c_pxa_set_master(struct pxa_i2c *i2c) +{ + if (i2c_debug) + dev_dbg(&i2c->adap.dev, "setting to bus master\n"); + + if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) != 0) { + dev_dbg(&i2c->adap.dev, "%s: unit is busy\n", __func__); + if (!i2c_pxa_wait_master(i2c)) { + dev_dbg(&i2c->adap.dev, "%s: error: unit busy\n", __func__); + return I2C_RETRY; + } + } + + writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c)); + return 0; +} + +#ifdef CONFIG_I2C_PXA_SLAVE +static int i2c_pxa_wait_slave(struct pxa_i2c *i2c) +{ + unsigned long timeout = jiffies + HZ*1; + + /* wait for stop */ + + show_state(i2c); + + while (time_before(jiffies, timeout)) { + if (i2c_debug > 1) + dev_dbg(&i2c->adap.dev, "%s: %ld: ISR=%08x, ICR=%08x, IBMR=%02x\n", + __func__, (long)jiffies, readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c))); + + if ((readl(_ISR(i2c)) & (ISR_UB|ISR_IBB)) == 0 || + (readl(_ISR(i2c)) & ISR_SAD) != 0 || + (readl(_ICR(i2c)) & ICR_SCLE) == 0) { + if (i2c_debug > 1) + dev_dbg(&i2c->adap.dev, "%s: done\n", __func__); + return 1; + } + + msleep(1); + } + + if (i2c_debug > 0) + dev_dbg(&i2c->adap.dev, "%s: did not free\n", __func__); + return 0; +} + +/* + * clear the hold on the bus, and take of anything else + * that has been configured + */ +static void i2c_pxa_set_slave(struct pxa_i2c *i2c, int errcode) +{ + show_state(i2c); + + if (errcode < 0) { + udelay(100); /* simple delay */ + } else { + /* we need to wait for the stop condition to end */ + + /* if we where in stop, then clear... */ + if (readl(_ICR(i2c)) & ICR_STOP) { + udelay(100); + writel(readl(_ICR(i2c)) & ~ICR_STOP, _ICR(i2c)); + } + + if (!i2c_pxa_wait_slave(i2c)) { + dev_err(&i2c->adap.dev, "%s: wait timedout\n", + __func__); + return; + } + } + + writel(readl(_ICR(i2c)) & ~(ICR_STOP|ICR_ACKNAK|ICR_MA), _ICR(i2c)); + writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c)); + + if (i2c_debug) { + dev_dbg(&i2c->adap.dev, "ICR now %08x, ISR %08x\n", readl(_ICR(i2c)), readl(_ISR(i2c))); + decode_ICR(readl(_ICR(i2c))); + } +} +#else +#define i2c_pxa_set_slave(i2c, err) do { } while (0) +#endif + +static void i2c_pxa_do_reset(struct pxa_i2c *i2c) +{ + /* reset according to 9.8 */ + writel(ICR_UR, _ICR(i2c)); + writel(I2C_ISR_INIT, _ISR(i2c)); + writel(readl(_ICR(i2c)) & ~ICR_UR, _ICR(i2c)); + + if (i2c->reg_isar && IS_ENABLED(CONFIG_I2C_PXA_SLAVE)) + writel(i2c->slave_addr, _ISAR(i2c)); + + /* set control register values */ + writel(I2C_ICR_INIT | (i2c->fast_mode ? i2c->fm_mask : 0), _ICR(i2c)); + writel(readl(_ICR(i2c)) | (i2c->high_mode ? i2c->hs_mask : 0), _ICR(i2c)); + +#ifdef CONFIG_I2C_PXA_SLAVE + dev_info(&i2c->adap.dev, "Enabling slave mode\n"); + writel(readl(_ICR(i2c)) | ICR_SADIE | ICR_ALDIE | ICR_SSDIE, _ICR(i2c)); +#endif + + i2c_pxa_set_slave(i2c, 0); +} + +static void i2c_pxa_enable(struct pxa_i2c *i2c) +{ + /* enable unit */ + writel(readl(_ICR(i2c)) | ICR_IUE, _ICR(i2c)); + udelay(100); +} + +static void i2c_pxa_reset(struct pxa_i2c *i2c) +{ + pr_debug("Resetting I2C Controller Unit\n"); + + /* abort any transfer currently under way */ + i2c_pxa_abort(i2c); + i2c_pxa_do_reset(i2c); + i2c_pxa_enable(i2c); +} + + +#ifdef CONFIG_I2C_PXA_SLAVE +/* + * PXA I2C Slave mode + */ + +static void i2c_pxa_slave_txempty(struct pxa_i2c *i2c, u32 isr) +{ + if (isr & ISR_BED) { + /* what should we do here? */ + } else { + u8 byte = 0; + + if (i2c->slave != NULL) + i2c_slave_event(i2c->slave, I2C_SLAVE_READ_PROCESSED, + &byte); + + writel(byte, _IDBR(i2c)); + writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c)); /* allow next byte */ + } +} + +static void i2c_pxa_slave_rxfull(struct pxa_i2c *i2c, u32 isr) +{ + u8 byte = readl(_IDBR(i2c)); + + if (i2c->slave != NULL) + i2c_slave_event(i2c->slave, I2C_SLAVE_WRITE_RECEIVED, &byte); + + writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c)); +} + +static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr) +{ + int timeout; + + if (i2c_debug > 0) + dev_dbg(&i2c->adap.dev, "SAD, mode is slave-%cx\n", + (isr & ISR_RWM) ? 'r' : 't'); + + if (i2c->slave != NULL) { + if (isr & ISR_RWM) { + u8 byte = 0; + + i2c_slave_event(i2c->slave, I2C_SLAVE_READ_REQUESTED, + &byte); + writel(byte, _IDBR(i2c)); + } else { + i2c_slave_event(i2c->slave, I2C_SLAVE_WRITE_REQUESTED, + NULL); + } + } + + /* + * slave could interrupt in the middle of us generating a + * start condition... if this happens, we'd better back off + * and stop holding the poor thing up + */ + writel(readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP), _ICR(i2c)); + writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c)); + + timeout = 0x10000; + + while (1) { + if ((readl(_IBMR(i2c)) & IBMR_SCLS) == IBMR_SCLS) + break; + + timeout--; + + if (timeout <= 0) { + dev_err(&i2c->adap.dev, "timeout waiting for SCL high\n"); + break; + } + } + + writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c)); +} + +static void i2c_pxa_slave_stop(struct pxa_i2c *i2c) +{ + if (i2c_debug > 2) + dev_dbg(&i2c->adap.dev, "ISR: SSD (Slave Stop)\n"); + + if (i2c->slave != NULL) + i2c_slave_event(i2c->slave, I2C_SLAVE_STOP, NULL); + + if (i2c_debug > 2) + dev_dbg(&i2c->adap.dev, "ISR: SSD (Slave Stop) acked\n"); + + /* + * If we have a master-mode message waiting, + * kick it off now that the slave has completed. + */ + if (i2c->msg) + i2c_pxa_master_complete(i2c, I2C_RETRY); +} + +static int i2c_pxa_slave_reg(struct i2c_client *slave) +{ + struct pxa_i2c *i2c = slave->adapter->algo_data; + + if (i2c->slave) + return -EBUSY; + + if (!i2c->reg_isar) + return -EAFNOSUPPORT; + + i2c->slave = slave; + i2c->slave_addr = slave->addr; + + writel(i2c->slave_addr, _ISAR(i2c)); + + return 0; +} + +static int i2c_pxa_slave_unreg(struct i2c_client *slave) +{ + struct pxa_i2c *i2c = slave->adapter->algo_data; + + WARN_ON(!i2c->slave); + + i2c->slave_addr = I2C_PXA_SLAVE_ADDR; + writel(i2c->slave_addr, _ISAR(i2c)); + + i2c->slave = NULL; + + return 0; +} +#else +static void i2c_pxa_slave_txempty(struct pxa_i2c *i2c, u32 isr) +{ + if (isr & ISR_BED) { + /* what should we do here? */ + } else { + writel(0, _IDBR(i2c)); + writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c)); + } +} + +static void i2c_pxa_slave_rxfull(struct pxa_i2c *i2c, u32 isr) +{ + writel(readl(_ICR(i2c)) | ICR_TB | ICR_ACKNAK, _ICR(i2c)); +} + +static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr) +{ + int timeout; + + /* + * slave could interrupt in the middle of us generating a + * start condition... if this happens, we'd better back off + * and stop holding the poor thing up + */ + writel(readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP), _ICR(i2c)); + writel(readl(_ICR(i2c)) | ICR_TB | ICR_ACKNAK, _ICR(i2c)); + + timeout = 0x10000; + + while (1) { + if ((readl(_IBMR(i2c)) & IBMR_SCLS) == IBMR_SCLS) + break; + + timeout--; + + if (timeout <= 0) { + dev_err(&i2c->adap.dev, "timeout waiting for SCL high\n"); + break; + } + } + + writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c)); +} + +static void i2c_pxa_slave_stop(struct pxa_i2c *i2c) +{ + if (i2c->msg) + i2c_pxa_master_complete(i2c, I2C_RETRY); +} +#endif + +/* + * PXA I2C Master mode + */ + +static inline void i2c_pxa_start_message(struct pxa_i2c *i2c) +{ + u32 icr; + + /* + * Step 1: target slave address into IDBR + */ + i2c->req_slave_addr = i2c_8bit_addr_from_msg(i2c->msg); + writel(i2c->req_slave_addr, _IDBR(i2c)); + + /* + * Step 2: initiate the write. + */ + icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE); + writel(icr | ICR_START | ICR_TB, _ICR(i2c)); +} + +static inline void i2c_pxa_stop_message(struct pxa_i2c *i2c) +{ + u32 icr; + + /* Clear the START, STOP, ACK, TB and MA flags */ + icr = readl(_ICR(i2c)); + icr &= ~(ICR_START | ICR_STOP | ICR_ACKNAK | ICR_TB | ICR_MA); + writel(icr, _ICR(i2c)); +} + +/* + * PXA I2C send master code + * 1. Load master code to IDBR and send it. + * Note for HS mode, set ICR [GPIOEN]. + * 2. Wait until win arbitration. + */ +static int i2c_pxa_send_mastercode(struct pxa_i2c *i2c) +{ + u32 icr; + long timeout; + + spin_lock_irq(&i2c->lock); + i2c->highmode_enter = true; + writel(i2c->master_code, _IDBR(i2c)); + + icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE); + icr |= ICR_GPIOEN | ICR_START | ICR_TB | ICR_ITEIE; + writel(icr, _ICR(i2c)); + + spin_unlock_irq(&i2c->lock); + timeout = wait_event_timeout(i2c->wait, + i2c->highmode_enter == false, HZ * 1); + + i2c->highmode_enter = false; + + return (timeout == 0) ? I2C_RETRY : 0; +} + +/* + * i2c_pxa_master_complete - complete the message and wake up. + */ +static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret) +{ + i2c->msg_ptr = 0; + i2c->msg = NULL; + i2c->msg_idx ++; + i2c->msg_num = 0; + if (ret) + i2c->msg_idx = ret; + if (!i2c->use_pio) + wake_up(&i2c->wait); +} + +static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr) +{ + u32 icr = readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP|ICR_ACKNAK|ICR_TB); + + again: + /* + * If ISR_ALD is set, we lost arbitration. + */ + if (isr & ISR_ALD) { + /* + * Do we need to do anything here? The PXA docs + * are vague about what happens. + */ + i2c_pxa_scream_blue_murder(i2c, "ALD set"); + + /* + * We ignore this error. We seem to see spurious ALDs + * for seemingly no reason. If we handle them as I think + * they should, we end up causing an I2C error, which + * is painful for some systems. + */ + return; /* ignore */ + } + + if ((isr & ISR_BED) && + (!((i2c->msg->flags & I2C_M_IGNORE_NAK) && + (isr & ISR_ACKNAK)))) { + int ret = BUS_ERROR; + + /* + * I2C bus error - either the device NAK'd us, or + * something more serious happened. If we were NAK'd + * on the initial address phase, we can retry. + */ + if (isr & ISR_ACKNAK) { + if (i2c->msg_ptr == 0 && i2c->msg_idx == 0) + ret = NO_SLAVE; + else + ret = XFER_NAKED; + } + i2c_pxa_master_complete(i2c, ret); + } else if (isr & ISR_RWM) { + /* + * Read mode. We have just sent the address byte, and + * now we must initiate the transfer. + */ + if (i2c->msg_ptr == i2c->msg->len - 1 && + i2c->msg_idx == i2c->msg_num - 1) + icr |= ICR_STOP | ICR_ACKNAK; + + icr |= ICR_ALDIE | ICR_TB; + } else if (i2c->msg_ptr < i2c->msg->len) { + /* + * Write mode. Write the next data byte. + */ + writel(i2c->msg->buf[i2c->msg_ptr++], _IDBR(i2c)); + + icr |= ICR_ALDIE | ICR_TB; + + /* + * If this is the last byte of the last message or last byte + * of any message with I2C_M_STOP (e.g. SCCB), send a STOP. + */ + if ((i2c->msg_ptr == i2c->msg->len) && + ((i2c->msg->flags & I2C_M_STOP) || + (i2c->msg_idx == i2c->msg_num - 1))) + icr |= ICR_STOP; + + } else if (i2c->msg_idx < i2c->msg_num - 1) { + /* + * Next segment of the message. + */ + i2c->msg_ptr = 0; + i2c->msg_idx ++; + i2c->msg++; + + /* + * If we aren't doing a repeated start and address, + * go back and try to send the next byte. Note that + * we do not support switching the R/W direction here. + */ + if (i2c->msg->flags & I2C_M_NOSTART) + goto again; + + /* + * Write the next address. + */ + i2c->req_slave_addr = i2c_8bit_addr_from_msg(i2c->msg); + writel(i2c->req_slave_addr, _IDBR(i2c)); + + /* + * And trigger a repeated start, and send the byte. + */ + icr &= ~ICR_ALDIE; + icr |= ICR_START | ICR_TB; + } else { + if (i2c->msg->len == 0) + icr |= ICR_MA; + i2c_pxa_master_complete(i2c, 0); + } + + i2c->icrlog[i2c->irqlogidx-1] = icr; + + writel(icr, _ICR(i2c)); + show_state(i2c); +} + +static void i2c_pxa_irq_rxfull(struct pxa_i2c *i2c, u32 isr) +{ + u32 icr = readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP|ICR_ACKNAK|ICR_TB); + + /* + * Read the byte. + */ + i2c->msg->buf[i2c->msg_ptr++] = readl(_IDBR(i2c)); + + if (i2c->msg_ptr < i2c->msg->len) { + /* + * If this is the last byte of the last + * message, send a STOP. + */ + if (i2c->msg_ptr == i2c->msg->len - 1) + icr |= ICR_STOP | ICR_ACKNAK; + + icr |= ICR_ALDIE | ICR_TB; + } else { + i2c_pxa_master_complete(i2c, 0); + } + + i2c->icrlog[i2c->irqlogidx-1] = icr; + + writel(icr, _ICR(i2c)); +} + +#define VALID_INT_SOURCE (ISR_SSD | ISR_ALD | ISR_ITE | ISR_IRF | \ + ISR_SAD | ISR_BED) +static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id) +{ + struct pxa_i2c *i2c = dev_id; + u32 isr = readl(_ISR(i2c)); + + if (!(isr & VALID_INT_SOURCE)) + return IRQ_NONE; + + if (i2c_debug > 2 && 0) { + dev_dbg(&i2c->adap.dev, "%s: ISR=%08x, ICR=%08x, IBMR=%02x\n", + __func__, isr, readl(_ICR(i2c)), readl(_IBMR(i2c))); + decode_ISR(isr); + } + + if (i2c->irqlogidx < ARRAY_SIZE(i2c->isrlog)) + i2c->isrlog[i2c->irqlogidx++] = isr; + + show_state(i2c); + + /* + * Always clear all pending IRQs. + */ + writel(isr & VALID_INT_SOURCE, _ISR(i2c)); + + if (isr & ISR_SAD) + i2c_pxa_slave_start(i2c, isr); + if (isr & ISR_SSD) + i2c_pxa_slave_stop(i2c); + + if (i2c_pxa_is_slavemode(i2c)) { + if (isr & ISR_ITE) + i2c_pxa_slave_txempty(i2c, isr); + if (isr & ISR_IRF) + i2c_pxa_slave_rxfull(i2c, isr); + } else if (i2c->msg && (!i2c->highmode_enter)) { + if (isr & ISR_ITE) + i2c_pxa_irq_txempty(i2c, isr); + if (isr & ISR_IRF) + i2c_pxa_irq_rxfull(i2c, isr); + } else if ((isr & ISR_ITE) && i2c->highmode_enter) { + i2c->highmode_enter = false; + wake_up(&i2c->wait); + } else { + i2c_pxa_scream_blue_murder(i2c, "spurious irq"); + } + + return IRQ_HANDLED; +} + +/* + * We are protected by the adapter bus mutex. + */ +static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num) +{ + long timeout; + int ret; + + /* + * Wait for the bus to become free. + */ + ret = i2c_pxa_wait_bus_not_busy(i2c); + if (ret) { + dev_err(&i2c->adap.dev, "i2c_pxa: timeout waiting for bus free\n"); + i2c_recover_bus(&i2c->adap); + goto out; + } + + /* + * Set master mode. + */ + ret = i2c_pxa_set_master(i2c); + if (ret) { + dev_err(&i2c->adap.dev, "i2c_pxa_set_master: error %d\n", ret); + goto out; + } + + if (i2c->high_mode) { + ret = i2c_pxa_send_mastercode(i2c); + if (ret) { + dev_err(&i2c->adap.dev, "i2c_pxa_send_mastercode timeout\n"); + goto out; + } + } + + spin_lock_irq(&i2c->lock); + + i2c->msg = msg; + i2c->msg_num = num; + i2c->msg_idx = 0; + i2c->msg_ptr = 0; + i2c->irqlogidx = 0; + + i2c_pxa_start_message(i2c); + + spin_unlock_irq(&i2c->lock); + + /* + * The rest of the processing occurs in the interrupt handler. + */ + timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5); + i2c_pxa_stop_message(i2c); + + /* + * We place the return code in i2c->msg_idx. + */ + ret = i2c->msg_idx; + + if (!timeout && i2c->msg_num) { + i2c_pxa_scream_blue_murder(i2c, "timeout with active message"); + i2c_recover_bus(&i2c->adap); + ret = I2C_RETRY; + } + + out: + return ret; +} + +static int i2c_pxa_internal_xfer(struct pxa_i2c *i2c, + struct i2c_msg *msgs, int num, + int (*xfer)(struct pxa_i2c *, + struct i2c_msg *, int num)) +{ + int ret, i; + + for (i = 0; ; ) { + ret = xfer(i2c, msgs, num); + if (ret != I2C_RETRY && ret != NO_SLAVE) + goto out; + if (++i >= i2c->adap.retries) + break; + + if (i2c_debug) + dev_dbg(&i2c->adap.dev, "Retrying transmission\n"); + udelay(100); + } + if (ret != NO_SLAVE) + i2c_pxa_scream_blue_murder(i2c, "exhausted retries"); + ret = -EREMOTEIO; + out: + i2c_pxa_set_slave(i2c, ret); + return ret; +} + +static int i2c_pxa_xfer(struct i2c_adapter *adap, + struct i2c_msg msgs[], int num) +{ + struct pxa_i2c *i2c = adap->algo_data; + + return i2c_pxa_internal_xfer(i2c, msgs, num, i2c_pxa_do_xfer); +} + +static u32 i2c_pxa_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | + I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART; +} + +static const struct i2c_algorithm i2c_pxa_algorithm = { + .master_xfer = i2c_pxa_xfer, + .functionality = i2c_pxa_functionality, +#ifdef CONFIG_I2C_PXA_SLAVE + .reg_slave = i2c_pxa_slave_reg, + .unreg_slave = i2c_pxa_slave_unreg, +#endif +}; + +/* Non-interrupt mode support */ +static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c) +{ + /* make timeout the same as for interrupt based functions */ + long timeout = 2 * DEF_TIMEOUT; + + /* + * Wait for the bus to become free. + */ + while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) + udelay(1000); + + if (timeout < 0) { + show_state(i2c); + dev_err(&i2c->adap.dev, + "i2c_pxa: timeout waiting for bus free (set_master)\n"); + return I2C_RETRY; + } + + /* + * Set master mode. + */ + writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c)); + + return 0; +} + +static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c, + struct i2c_msg *msg, int num) +{ + unsigned long timeout = 500000; /* 5 seconds */ + int ret = 0; + + ret = i2c_pxa_pio_set_master(i2c); + if (ret) + goto out; + + i2c->msg = msg; + i2c->msg_num = num; + i2c->msg_idx = 0; + i2c->msg_ptr = 0; + i2c->irqlogidx = 0; + + i2c_pxa_start_message(i2c); + + while (i2c->msg_num > 0 && --timeout) { + i2c_pxa_handler(0, i2c); + udelay(10); + } + + i2c_pxa_stop_message(i2c); + + /* + * We place the return code in i2c->msg_idx. + */ + ret = i2c->msg_idx; + +out: + if (timeout == 0) { + i2c_pxa_scream_blue_murder(i2c, "timeout (do_pio_xfer)"); + ret = I2C_RETRY; + } + + return ret; +} + +static int i2c_pxa_pio_xfer(struct i2c_adapter *adap, + struct i2c_msg msgs[], int num) +{ + struct pxa_i2c *i2c = adap->algo_data; + + /* If the I2C controller is disabled we need to reset it + (probably due to a suspend/resume destroying state). We do + this here as we can then avoid worrying about resuming the + controller before its users. */ + if (!(readl(_ICR(i2c)) & ICR_IUE)) + i2c_pxa_reset(i2c); + + return i2c_pxa_internal_xfer(i2c, msgs, num, i2c_pxa_do_pio_xfer); +} + +static const struct i2c_algorithm i2c_pxa_pio_algorithm = { + .master_xfer = i2c_pxa_pio_xfer, + .functionality = i2c_pxa_functionality, +#ifdef CONFIG_I2C_PXA_SLAVE + .reg_slave = i2c_pxa_slave_reg, + .unreg_slave = i2c_pxa_slave_unreg, +#endif +}; + +static int i2c_pxa_probe_dt(struct platform_device *pdev, struct pxa_i2c *i2c, + enum pxa_i2c_types *i2c_types) +{ + struct device_node *np = pdev->dev.of_node; + const struct of_device_id *of_id = + of_match_device(i2c_pxa_dt_ids, &pdev->dev); + + if (!of_id) + return 1; + + /* For device tree we always use the dynamic or alias-assigned ID */ + i2c->adap.nr = -1; + + i2c->use_pio = of_property_read_bool(np, "mrvl,i2c-polling"); + i2c->fast_mode = of_property_read_bool(np, "mrvl,i2c-fast-mode"); + + *i2c_types = (enum pxa_i2c_types)(of_id->data); + + return 0; +} + +static int i2c_pxa_probe_pdata(struct platform_device *pdev, + struct pxa_i2c *i2c, + enum pxa_i2c_types *i2c_types) +{ + struct i2c_pxa_platform_data *plat = dev_get_platdata(&pdev->dev); + const struct platform_device_id *id = platform_get_device_id(pdev); + + *i2c_types = id->driver_data; + if (plat) { + i2c->use_pio = plat->use_pio; + i2c->fast_mode = plat->fast_mode; + i2c->high_mode = plat->high_mode; + i2c->master_code = plat->master_code; + if (!i2c->master_code) + i2c->master_code = 0xe; + i2c->rate = plat->rate; + } + return 0; +} + +static void i2c_pxa_prepare_recovery(struct i2c_adapter *adap) +{ + struct pxa_i2c *i2c = adap->algo_data; + u32 ibmr = readl(_IBMR(i2c)); + + /* + * Program the GPIOs to reflect the current I2C bus state while + * we transition to recovery; this avoids glitching the bus. + */ + gpiod_set_value(i2c->recovery.scl_gpiod, ibmr & IBMR_SCLS); + gpiod_set_value(i2c->recovery.sda_gpiod, ibmr & IBMR_SDAS); + + WARN_ON(pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_recovery)); +} + +static void i2c_pxa_unprepare_recovery(struct i2c_adapter *adap) +{ + struct pxa_i2c *i2c = adap->algo_data; + u32 isr; + + /* + * The bus should now be free. Clear up the I2C controller before + * handing control of the bus back to avoid the bus changing state. + */ + isr = readl(_ISR(i2c)); + if (isr & (ISR_UB | ISR_IBB)) { + dev_dbg(&i2c->adap.dev, + "recovery: resetting controller, ISR=0x%08x\n", isr); + i2c_pxa_do_reset(i2c); + } + + WARN_ON(pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_default)); + + dev_dbg(&i2c->adap.dev, "recovery: IBMR 0x%08x ISR 0x%08x\n", + readl(_IBMR(i2c)), readl(_ISR(i2c))); + + i2c_pxa_enable(i2c); +} + +static int i2c_pxa_init_recovery(struct pxa_i2c *i2c) +{ + struct i2c_bus_recovery_info *bri = &i2c->recovery; + struct device *dev = i2c->adap.dev.parent; + + /* + * When slave mode is enabled, we are not the only master on the bus. + * Bus recovery can only be performed when we are the master, which + * we can't be certain of. Therefore, when slave mode is enabled, do + * not configure bus recovery. + */ + if (IS_ENABLED(CONFIG_I2C_PXA_SLAVE)) + return 0; + + i2c->pinctrl = devm_pinctrl_get(dev); + if (PTR_ERR(i2c->pinctrl) == -ENODEV) + i2c->pinctrl = NULL; + if (IS_ERR(i2c->pinctrl)) + return PTR_ERR(i2c->pinctrl); + + if (!i2c->pinctrl) + return 0; + + i2c->pinctrl_default = pinctrl_lookup_state(i2c->pinctrl, + PINCTRL_STATE_DEFAULT); + i2c->pinctrl_recovery = pinctrl_lookup_state(i2c->pinctrl, "recovery"); + + if (IS_ERR(i2c->pinctrl_default) || IS_ERR(i2c->pinctrl_recovery)) { + dev_info(dev, "missing pinmux recovery information: %ld %ld\n", + PTR_ERR(i2c->pinctrl_default), + PTR_ERR(i2c->pinctrl_recovery)); + return 0; + } + + /* + * Claiming GPIOs can influence the pinmux state, and may glitch the + * I2C bus. Do this carefully. + */ + bri->scl_gpiod = devm_gpiod_get(dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN); + if (bri->scl_gpiod == ERR_PTR(-EPROBE_DEFER)) + return -EPROBE_DEFER; + if (IS_ERR(bri->scl_gpiod)) { + dev_info(dev, "missing scl gpio recovery information: %pe\n", + bri->scl_gpiod); + return 0; + } + + /* + * We have SCL. Pull SCL low and wait a bit so that SDA glitches + * have no effect. + */ + gpiod_direction_output(bri->scl_gpiod, 0); + udelay(10); + bri->sda_gpiod = devm_gpiod_get(dev, "sda", GPIOD_OUT_HIGH_OPEN_DRAIN); + + /* Wait a bit in case of a SDA glitch, and then release SCL. */ + udelay(10); + gpiod_direction_output(bri->scl_gpiod, 1); + + if (bri->sda_gpiod == ERR_PTR(-EPROBE_DEFER)) + return -EPROBE_DEFER; + + if (IS_ERR(bri->sda_gpiod)) { + dev_info(dev, "missing sda gpio recovery information: %pe\n", + bri->sda_gpiod); + return 0; + } + + bri->prepare_recovery = i2c_pxa_prepare_recovery; + bri->unprepare_recovery = i2c_pxa_unprepare_recovery; + bri->recover_bus = i2c_generic_scl_recovery; + + i2c->adap.bus_recovery_info = bri; + + /* + * Claiming GPIOs can change the pinmux state, which confuses the + * pinctrl since pinctrl's idea of the current setting is unaffected + * by the pinmux change caused by claiming the GPIO. Work around that + * by switching pinctrl to the GPIO state here. We do it this way to + * avoid glitching the I2C bus. + */ + pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_recovery); + + return pinctrl_select_state(i2c->pinctrl, i2c->pinctrl_default); +} + +static int i2c_pxa_probe(struct platform_device *dev) +{ + struct i2c_pxa_platform_data *plat = dev_get_platdata(&dev->dev); + enum pxa_i2c_types i2c_type; + struct pxa_i2c *i2c; + struct resource *res; + int ret, irq; + + i2c = devm_kzalloc(&dev->dev, sizeof(struct pxa_i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + /* Default adapter num to device id; i2c_pxa_probe_dt can override. */ + i2c->adap.nr = dev->id; + i2c->adap.owner = THIS_MODULE; + i2c->adap.retries = 5; + i2c->adap.algo_data = i2c; + i2c->adap.dev.parent = &dev->dev; +#ifdef CONFIG_OF + i2c->adap.dev.of_node = dev->dev.of_node; +#endif + + i2c->reg_base = devm_platform_get_and_ioremap_resource(dev, 0, &res); + if (IS_ERR(i2c->reg_base)) + return PTR_ERR(i2c->reg_base); + + irq = platform_get_irq(dev, 0); + if (irq < 0) + return irq; + + ret = i2c_pxa_init_recovery(i2c); + if (ret) + return ret; + + ret = i2c_pxa_probe_dt(dev, i2c, &i2c_type); + if (ret > 0) + ret = i2c_pxa_probe_pdata(dev, i2c, &i2c_type); + if (ret < 0) + return ret; + + spin_lock_init(&i2c->lock); + init_waitqueue_head(&i2c->wait); + + strscpy(i2c->adap.name, "pxa_i2c-i2c", sizeof(i2c->adap.name)); + + i2c->clk = devm_clk_get(&dev->dev, NULL); + if (IS_ERR(i2c->clk)) + return dev_err_probe(&dev->dev, PTR_ERR(i2c->clk), + "failed to get the clk\n"); + + i2c->reg_ibmr = i2c->reg_base + pxa_reg_layout[i2c_type].ibmr; + i2c->reg_idbr = i2c->reg_base + pxa_reg_layout[i2c_type].idbr; + i2c->reg_icr = i2c->reg_base + pxa_reg_layout[i2c_type].icr; + i2c->reg_isr = i2c->reg_base + pxa_reg_layout[i2c_type].isr; + i2c->fm_mask = pxa_reg_layout[i2c_type].fm; + i2c->hs_mask = pxa_reg_layout[i2c_type].hs; + + if (i2c_type != REGS_CE4100) + i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar; + + if (i2c_type == REGS_PXA910) { + i2c->reg_ilcr = i2c->reg_base + pxa_reg_layout[i2c_type].ilcr; + i2c->reg_iwcr = i2c->reg_base + pxa_reg_layout[i2c_type].iwcr; + } + + i2c->iobase = res->start; + i2c->iosize = resource_size(res); + + i2c->irq = irq; + + i2c->slave_addr = I2C_PXA_SLAVE_ADDR; + i2c->highmode_enter = false; + + if (plat) { + i2c->adap.class = plat->class; + } + + if (i2c->high_mode) { + if (i2c->rate) { + clk_set_rate(i2c->clk, i2c->rate); + pr_info("i2c: <%s> set rate to %ld\n", + i2c->adap.name, clk_get_rate(i2c->clk)); + } else + pr_warn("i2c: <%s> clock rate not set\n", + i2c->adap.name); + } + + clk_prepare_enable(i2c->clk); + + if (i2c->use_pio) { + i2c->adap.algo = &i2c_pxa_pio_algorithm; + } else { + i2c->adap.algo = &i2c_pxa_algorithm; + ret = devm_request_irq(&dev->dev, irq, i2c_pxa_handler, + IRQF_SHARED | IRQF_NO_SUSPEND, + dev_name(&dev->dev), i2c); + if (ret) { + dev_err(&dev->dev, "failed to request irq: %d\n", ret); + goto ereqirq; + } + } + + i2c_pxa_reset(i2c); + + ret = i2c_add_numbered_adapter(&i2c->adap); + if (ret < 0) + goto ereqirq; + + platform_set_drvdata(dev, i2c); + +#ifdef CONFIG_I2C_PXA_SLAVE + dev_info(&i2c->adap.dev, " PXA I2C adapter, slave address %d\n", + i2c->slave_addr); +#else + dev_info(&i2c->adap.dev, " PXA I2C adapter\n"); +#endif + return 0; + +ereqirq: + clk_disable_unprepare(i2c->clk); + return ret; +} + +static void i2c_pxa_remove(struct platform_device *dev) +{ + struct pxa_i2c *i2c = platform_get_drvdata(dev); + + i2c_del_adapter(&i2c->adap); + + clk_disable_unprepare(i2c->clk); +} + +static int i2c_pxa_suspend_noirq(struct device *dev) +{ + struct pxa_i2c *i2c = dev_get_drvdata(dev); + + clk_disable(i2c->clk); + + return 0; +} + +static int i2c_pxa_resume_noirq(struct device *dev) +{ + struct pxa_i2c *i2c = dev_get_drvdata(dev); + + clk_enable(i2c->clk); + i2c_pxa_reset(i2c); + + return 0; +} + +static const struct dev_pm_ops i2c_pxa_dev_pm_ops = { + .suspend_noirq = i2c_pxa_suspend_noirq, + .resume_noirq = i2c_pxa_resume_noirq, +}; + +static struct platform_driver i2c_pxa_driver = { + .probe = i2c_pxa_probe, + .remove_new = i2c_pxa_remove, + .driver = { + .name = "pxa2xx-i2c", + .pm = pm_sleep_ptr(&i2c_pxa_dev_pm_ops), + .of_match_table = i2c_pxa_dt_ids, + }, + .id_table = i2c_pxa_id_table, +}; + +static int __init i2c_adap_pxa_init(void) +{ + return platform_driver_register(&i2c_pxa_driver); +} + +static void __exit i2c_adap_pxa_exit(void) +{ + platform_driver_unregister(&i2c_pxa_driver); +} + +MODULE_LICENSE("GPL"); + +subsys_initcall(i2c_adap_pxa_init); +module_exit(i2c_adap_pxa_exit); diff --git a/drivers/i2c/busses/i2c-qcom-cci.c b/drivers/i2c/busses/i2c-qcom-cci.c new file mode 100644 index 000000000..414882c57 --- /dev/null +++ b/drivers/i2c/busses/i2c-qcom-cci.c @@ -0,0 +1,842 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2012-2016, The Linux Foundation. All rights reserved. +// Copyright (c) 2017-2022 Linaro Limited. + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/i2c.h> +#include <linux/io.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> + +#define CCI_HW_VERSION 0x0 +#define CCI_RESET_CMD 0x004 +#define CCI_RESET_CMD_MASK 0x0f73f3f7 +#define CCI_RESET_CMD_M0_MASK 0x000003f1 +#define CCI_RESET_CMD_M1_MASK 0x0003f001 +#define CCI_QUEUE_START 0x008 +#define CCI_HALT_REQ 0x034 +#define CCI_HALT_REQ_I2C_M0_Q0Q1 BIT(0) +#define CCI_HALT_REQ_I2C_M1_Q0Q1 BIT(1) + +#define CCI_I2C_Mm_SCL_CTL(m) (0x100 + 0x100 * (m)) +#define CCI_I2C_Mm_SDA_CTL_0(m) (0x104 + 0x100 * (m)) +#define CCI_I2C_Mm_SDA_CTL_1(m) (0x108 + 0x100 * (m)) +#define CCI_I2C_Mm_SDA_CTL_2(m) (0x10c + 0x100 * (m)) +#define CCI_I2C_Mm_MISC_CTL(m) (0x110 + 0x100 * (m)) + +#define CCI_I2C_Mm_READ_DATA(m) (0x118 + 0x100 * (m)) +#define CCI_I2C_Mm_READ_BUF_LEVEL(m) (0x11c + 0x100 * (m)) +#define CCI_I2C_Mm_Qn_EXEC_WORD_CNT(m, n) (0x300 + 0x200 * (m) + 0x100 * (n)) +#define CCI_I2C_Mm_Qn_CUR_WORD_CNT(m, n) (0x304 + 0x200 * (m) + 0x100 * (n)) +#define CCI_I2C_Mm_Qn_CUR_CMD(m, n) (0x308 + 0x200 * (m) + 0x100 * (n)) +#define CCI_I2C_Mm_Qn_REPORT_STATUS(m, n) (0x30c + 0x200 * (m) + 0x100 * (n)) +#define CCI_I2C_Mm_Qn_LOAD_DATA(m, n) (0x310 + 0x200 * (m) + 0x100 * (n)) + +#define CCI_IRQ_GLOBAL_CLEAR_CMD 0xc00 +#define CCI_IRQ_MASK_0 0xc04 +#define CCI_IRQ_MASK_0_I2C_M0_RD_DONE BIT(0) +#define CCI_IRQ_MASK_0_I2C_M0_Q0_REPORT BIT(4) +#define CCI_IRQ_MASK_0_I2C_M0_Q1_REPORT BIT(8) +#define CCI_IRQ_MASK_0_I2C_M1_RD_DONE BIT(12) +#define CCI_IRQ_MASK_0_I2C_M1_Q0_REPORT BIT(16) +#define CCI_IRQ_MASK_0_I2C_M1_Q1_REPORT BIT(20) +#define CCI_IRQ_MASK_0_RST_DONE_ACK BIT(24) +#define CCI_IRQ_MASK_0_I2C_M0_Q0Q1_HALT_ACK BIT(25) +#define CCI_IRQ_MASK_0_I2C_M1_Q0Q1_HALT_ACK BIT(26) +#define CCI_IRQ_MASK_0_I2C_M0_ERROR 0x18000ee6 +#define CCI_IRQ_MASK_0_I2C_M1_ERROR 0x60ee6000 +#define CCI_IRQ_CLEAR_0 0xc08 +#define CCI_IRQ_STATUS_0 0xc0c +#define CCI_IRQ_STATUS_0_I2C_M0_RD_DONE BIT(0) +#define CCI_IRQ_STATUS_0_I2C_M0_Q0_REPORT BIT(4) +#define CCI_IRQ_STATUS_0_I2C_M0_Q1_REPORT BIT(8) +#define CCI_IRQ_STATUS_0_I2C_M1_RD_DONE BIT(12) +#define CCI_IRQ_STATUS_0_I2C_M1_Q0_REPORT BIT(16) +#define CCI_IRQ_STATUS_0_I2C_M1_Q1_REPORT BIT(20) +#define CCI_IRQ_STATUS_0_RST_DONE_ACK BIT(24) +#define CCI_IRQ_STATUS_0_I2C_M0_Q0Q1_HALT_ACK BIT(25) +#define CCI_IRQ_STATUS_0_I2C_M1_Q0Q1_HALT_ACK BIT(26) +#define CCI_IRQ_STATUS_0_I2C_M0_Q0_NACK_ERR BIT(27) +#define CCI_IRQ_STATUS_0_I2C_M0_Q1_NACK_ERR BIT(28) +#define CCI_IRQ_STATUS_0_I2C_M1_Q0_NACK_ERR BIT(29) +#define CCI_IRQ_STATUS_0_I2C_M1_Q1_NACK_ERR BIT(30) +#define CCI_IRQ_STATUS_0_I2C_M0_ERROR 0x18000ee6 +#define CCI_IRQ_STATUS_0_I2C_M1_ERROR 0x60ee6000 + +#define CCI_TIMEOUT (msecs_to_jiffies(100)) +#define NUM_MASTERS 2 +#define NUM_QUEUES 2 + +/* Max number of resources + 1 for a NULL terminator */ +#define CCI_RES_MAX 6 + +#define CCI_I2C_SET_PARAM 1 +#define CCI_I2C_REPORT 8 +#define CCI_I2C_WRITE 9 +#define CCI_I2C_READ 10 + +#define CCI_I2C_REPORT_IRQ_EN BIT(8) + +enum { + I2C_MODE_STANDARD, + I2C_MODE_FAST, + I2C_MODE_FAST_PLUS, +}; + +enum cci_i2c_queue_t { + QUEUE_0, + QUEUE_1 +}; + +struct hw_params { + u16 thigh; /* HIGH period of the SCL clock in clock ticks */ + u16 tlow; /* LOW period of the SCL clock */ + u16 tsu_sto; /* set-up time for STOP condition */ + u16 tsu_sta; /* set-up time for a repeated START condition */ + u16 thd_dat; /* data hold time */ + u16 thd_sta; /* hold time (repeated) START condition */ + u16 tbuf; /* bus free time between a STOP and START condition */ + u8 scl_stretch_en; + u16 trdhld; + u16 tsp; /* pulse width of spikes suppressed by the input filter */ +}; + +struct cci; + +struct cci_master { + struct i2c_adapter adap; + u16 master; + u8 mode; + int status; + struct completion irq_complete; + struct cci *cci; +}; + +struct cci_data { + unsigned int num_masters; + struct i2c_adapter_quirks quirks; + u16 queue_size[NUM_QUEUES]; + unsigned long cci_clk_rate; + struct hw_params params[3]; +}; + +struct cci { + struct device *dev; + void __iomem *base; + unsigned int irq; + const struct cci_data *data; + struct clk_bulk_data *clocks; + int nclocks; + struct cci_master master[NUM_MASTERS]; +}; + +static irqreturn_t cci_isr(int irq, void *dev) +{ + struct cci *cci = dev; + u32 val, reset = 0; + int ret = IRQ_NONE; + + val = readl(cci->base + CCI_IRQ_STATUS_0); + writel(val, cci->base + CCI_IRQ_CLEAR_0); + writel(0x1, cci->base + CCI_IRQ_GLOBAL_CLEAR_CMD); + + if (val & CCI_IRQ_STATUS_0_RST_DONE_ACK) { + complete(&cci->master[0].irq_complete); + if (cci->master[1].master) + complete(&cci->master[1].irq_complete); + ret = IRQ_HANDLED; + } + + if (val & CCI_IRQ_STATUS_0_I2C_M0_RD_DONE || + val & CCI_IRQ_STATUS_0_I2C_M0_Q0_REPORT || + val & CCI_IRQ_STATUS_0_I2C_M0_Q1_REPORT) { + cci->master[0].status = 0; + complete(&cci->master[0].irq_complete); + ret = IRQ_HANDLED; + } + + if (val & CCI_IRQ_STATUS_0_I2C_M1_RD_DONE || + val & CCI_IRQ_STATUS_0_I2C_M1_Q0_REPORT || + val & CCI_IRQ_STATUS_0_I2C_M1_Q1_REPORT) { + cci->master[1].status = 0; + complete(&cci->master[1].irq_complete); + ret = IRQ_HANDLED; + } + + if (unlikely(val & CCI_IRQ_STATUS_0_I2C_M0_Q0Q1_HALT_ACK)) { + reset = CCI_RESET_CMD_M0_MASK; + ret = IRQ_HANDLED; + } + + if (unlikely(val & CCI_IRQ_STATUS_0_I2C_M1_Q0Q1_HALT_ACK)) { + reset = CCI_RESET_CMD_M1_MASK; + ret = IRQ_HANDLED; + } + + if (unlikely(reset)) + writel(reset, cci->base + CCI_RESET_CMD); + + if (unlikely(val & CCI_IRQ_STATUS_0_I2C_M0_ERROR)) { + if (val & CCI_IRQ_STATUS_0_I2C_M0_Q0_NACK_ERR || + val & CCI_IRQ_STATUS_0_I2C_M0_Q1_NACK_ERR) + cci->master[0].status = -ENXIO; + else + cci->master[0].status = -EIO; + + writel(CCI_HALT_REQ_I2C_M0_Q0Q1, cci->base + CCI_HALT_REQ); + ret = IRQ_HANDLED; + } + + if (unlikely(val & CCI_IRQ_STATUS_0_I2C_M1_ERROR)) { + if (val & CCI_IRQ_STATUS_0_I2C_M1_Q0_NACK_ERR || + val & CCI_IRQ_STATUS_0_I2C_M1_Q1_NACK_ERR) + cci->master[1].status = -ENXIO; + else + cci->master[1].status = -EIO; + + writel(CCI_HALT_REQ_I2C_M1_Q0Q1, cci->base + CCI_HALT_REQ); + ret = IRQ_HANDLED; + } + + return ret; +} + +static int cci_halt(struct cci *cci, u8 master_num) +{ + struct cci_master *master; + u32 val; + + if (master_num >= cci->data->num_masters) { + dev_err(cci->dev, "Unsupported master idx (%u)\n", master_num); + return -EINVAL; + } + + val = BIT(master_num); + master = &cci->master[master_num]; + + reinit_completion(&master->irq_complete); + writel(val, cci->base + CCI_HALT_REQ); + + if (!wait_for_completion_timeout(&master->irq_complete, CCI_TIMEOUT)) { + dev_err(cci->dev, "CCI halt timeout\n"); + return -ETIMEDOUT; + } + + return 0; +} + +static int cci_reset(struct cci *cci) +{ + /* + * we reset the whole controller, here and for implicity use + * master[0].xxx for waiting on it. + */ + reinit_completion(&cci->master[0].irq_complete); + writel(CCI_RESET_CMD_MASK, cci->base + CCI_RESET_CMD); + + if (!wait_for_completion_timeout(&cci->master[0].irq_complete, + CCI_TIMEOUT)) { + dev_err(cci->dev, "CCI reset timeout\n"); + return -ETIMEDOUT; + } + + return 0; +} + +static int cci_init(struct cci *cci) +{ + u32 val = CCI_IRQ_MASK_0_I2C_M0_RD_DONE | + CCI_IRQ_MASK_0_I2C_M0_Q0_REPORT | + CCI_IRQ_MASK_0_I2C_M0_Q1_REPORT | + CCI_IRQ_MASK_0_I2C_M1_RD_DONE | + CCI_IRQ_MASK_0_I2C_M1_Q0_REPORT | + CCI_IRQ_MASK_0_I2C_M1_Q1_REPORT | + CCI_IRQ_MASK_0_RST_DONE_ACK | + CCI_IRQ_MASK_0_I2C_M0_Q0Q1_HALT_ACK | + CCI_IRQ_MASK_0_I2C_M1_Q0Q1_HALT_ACK | + CCI_IRQ_MASK_0_I2C_M0_ERROR | + CCI_IRQ_MASK_0_I2C_M1_ERROR; + int i; + + writel(val, cci->base + CCI_IRQ_MASK_0); + + for (i = 0; i < cci->data->num_masters; i++) { + int mode = cci->master[i].mode; + const struct hw_params *hw; + + if (!cci->master[i].cci) + continue; + + hw = &cci->data->params[mode]; + + val = hw->thigh << 16 | hw->tlow; + writel(val, cci->base + CCI_I2C_Mm_SCL_CTL(i)); + + val = hw->tsu_sto << 16 | hw->tsu_sta; + writel(val, cci->base + CCI_I2C_Mm_SDA_CTL_0(i)); + + val = hw->thd_dat << 16 | hw->thd_sta; + writel(val, cci->base + CCI_I2C_Mm_SDA_CTL_1(i)); + + val = hw->tbuf; + writel(val, cci->base + CCI_I2C_Mm_SDA_CTL_2(i)); + + val = hw->scl_stretch_en << 8 | hw->trdhld << 4 | hw->tsp; + writel(val, cci->base + CCI_I2C_Mm_MISC_CTL(i)); + } + + return 0; +} + +static int cci_run_queue(struct cci *cci, u8 master, u8 queue) +{ + u32 val; + + val = readl(cci->base + CCI_I2C_Mm_Qn_CUR_WORD_CNT(master, queue)); + writel(val, cci->base + CCI_I2C_Mm_Qn_EXEC_WORD_CNT(master, queue)); + + reinit_completion(&cci->master[master].irq_complete); + val = BIT(master * 2 + queue); + writel(val, cci->base + CCI_QUEUE_START); + + if (!wait_for_completion_timeout(&cci->master[master].irq_complete, + CCI_TIMEOUT)) { + dev_err(cci->dev, "master %d queue %d timeout\n", + master, queue); + cci_reset(cci); + cci_init(cci); + return -ETIMEDOUT; + } + + return cci->master[master].status; +} + +static int cci_validate_queue(struct cci *cci, u8 master, u8 queue) +{ + u32 val; + + val = readl(cci->base + CCI_I2C_Mm_Qn_CUR_WORD_CNT(master, queue)); + if (val == cci->data->queue_size[queue]) + return -EINVAL; + + if (!val) + return 0; + + val = CCI_I2C_REPORT | CCI_I2C_REPORT_IRQ_EN; + writel(val, cci->base + CCI_I2C_Mm_Qn_LOAD_DATA(master, queue)); + + return cci_run_queue(cci, master, queue); +} + +static int cci_i2c_read(struct cci *cci, u16 master, + u16 addr, u8 *buf, u16 len) +{ + u32 val, words_read, words_exp; + u8 queue = QUEUE_1; + int i, index = 0, ret; + bool first = true; + + /* + * Call validate queue to make sure queue is empty before starting. + * This is to avoid overflow / underflow of queue. + */ + ret = cci_validate_queue(cci, master, queue); + if (ret < 0) + return ret; + + val = CCI_I2C_SET_PARAM | (addr & 0x7f) << 4; + writel(val, cci->base + CCI_I2C_Mm_Qn_LOAD_DATA(master, queue)); + + val = CCI_I2C_READ | len << 4; + writel(val, cci->base + CCI_I2C_Mm_Qn_LOAD_DATA(master, queue)); + + ret = cci_run_queue(cci, master, queue); + if (ret < 0) + return ret; + + words_read = readl(cci->base + CCI_I2C_Mm_READ_BUF_LEVEL(master)); + words_exp = len / 4 + 1; + if (words_read != words_exp) { + dev_err(cci->dev, "words read = %d, words expected = %d\n", + words_read, words_exp); + return -EIO; + } + + do { + val = readl(cci->base + CCI_I2C_Mm_READ_DATA(master)); + + for (i = 0; i < 4 && index < len; i++) { + if (first) { + /* The LS byte of this register represents the + * first byte read from the slave during a read + * access. + */ + first = false; + continue; + } + buf[index++] = (val >> (i * 8)) & 0xff; + } + } while (--words_read); + + return 0; +} + +static int cci_i2c_write(struct cci *cci, u16 master, + u16 addr, u8 *buf, u16 len) +{ + u8 queue = QUEUE_0; + u8 load[12] = { 0 }; + int i = 0, j, ret; + u32 val; + + /* + * Call validate queue to make sure queue is empty before starting. + * This is to avoid overflow / underflow of queue. + */ + ret = cci_validate_queue(cci, master, queue); + if (ret < 0) + return ret; + + val = CCI_I2C_SET_PARAM | (addr & 0x7f) << 4; + writel(val, cci->base + CCI_I2C_Mm_Qn_LOAD_DATA(master, queue)); + + load[i++] = CCI_I2C_WRITE | len << 4; + + for (j = 0; j < len; j++) + load[i++] = buf[j]; + + for (j = 0; j < i; j += 4) { + val = load[j]; + val |= load[j + 1] << 8; + val |= load[j + 2] << 16; + val |= load[j + 3] << 24; + writel(val, cci->base + CCI_I2C_Mm_Qn_LOAD_DATA(master, queue)); + } + + val = CCI_I2C_REPORT | CCI_I2C_REPORT_IRQ_EN; + writel(val, cci->base + CCI_I2C_Mm_Qn_LOAD_DATA(master, queue)); + + return cci_run_queue(cci, master, queue); +} + +static int cci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + struct cci_master *cci_master = i2c_get_adapdata(adap); + struct cci *cci = cci_master->cci; + int i, ret; + + ret = pm_runtime_get_sync(cci->dev); + if (ret < 0) + goto err; + + for (i = 0; i < num; i++) { + if (msgs[i].flags & I2C_M_RD) + ret = cci_i2c_read(cci, cci_master->master, + msgs[i].addr, msgs[i].buf, + msgs[i].len); + else + ret = cci_i2c_write(cci, cci_master->master, + msgs[i].addr, msgs[i].buf, + msgs[i].len); + + if (ret < 0) + break; + } + + if (!ret) + ret = num; + +err: + pm_runtime_mark_last_busy(cci->dev); + pm_runtime_put_autosuspend(cci->dev); + + return ret; +} + +static u32 cci_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm cci_algo = { + .master_xfer = cci_xfer, + .functionality = cci_func, +}; + +static int cci_enable_clocks(struct cci *cci) +{ + return clk_bulk_prepare_enable(cci->nclocks, cci->clocks); +} + +static void cci_disable_clocks(struct cci *cci) +{ + clk_bulk_disable_unprepare(cci->nclocks, cci->clocks); +} + +static int __maybe_unused cci_suspend_runtime(struct device *dev) +{ + struct cci *cci = dev_get_drvdata(dev); + + cci_disable_clocks(cci); + return 0; +} + +static int __maybe_unused cci_resume_runtime(struct device *dev) +{ + struct cci *cci = dev_get_drvdata(dev); + int ret; + + ret = cci_enable_clocks(cci); + if (ret) + return ret; + + cci_init(cci); + return 0; +} + +static int __maybe_unused cci_suspend(struct device *dev) +{ + if (!pm_runtime_suspended(dev)) + return cci_suspend_runtime(dev); + + return 0; +} + +static int __maybe_unused cci_resume(struct device *dev) +{ + cci_resume_runtime(dev); + pm_runtime_mark_last_busy(dev); + pm_request_autosuspend(dev); + + return 0; +} + +static const struct dev_pm_ops qcom_cci_pm = { + SET_SYSTEM_SLEEP_PM_OPS(cci_suspend, cci_resume) + SET_RUNTIME_PM_OPS(cci_suspend_runtime, cci_resume_runtime, NULL) +}; + +static int cci_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + unsigned long cci_clk_rate = 0; + struct device_node *child; + struct resource *r; + struct cci *cci; + int ret, i; + u32 val; + + cci = devm_kzalloc(dev, sizeof(*cci), GFP_KERNEL); + if (!cci) + return -ENOMEM; + + cci->dev = dev; + platform_set_drvdata(pdev, cci); + cci->data = device_get_match_data(dev); + if (!cci->data) + return -ENOENT; + + for_each_available_child_of_node(dev->of_node, child) { + struct cci_master *master; + u32 idx; + + ret = of_property_read_u32(child, "reg", &idx); + if (ret) { + dev_err(dev, "%pOF invalid 'reg' property", child); + continue; + } + + if (idx >= cci->data->num_masters) { + dev_err(dev, "%pOF invalid 'reg' value: %u (max is %u)", + child, idx, cci->data->num_masters - 1); + continue; + } + + master = &cci->master[idx]; + master->adap.quirks = &cci->data->quirks; + master->adap.algo = &cci_algo; + master->adap.dev.parent = dev; + master->adap.dev.of_node = of_node_get(child); + master->master = idx; + master->cci = cci; + + i2c_set_adapdata(&master->adap, master); + snprintf(master->adap.name, sizeof(master->adap.name), "Qualcomm-CCI"); + + master->mode = I2C_MODE_STANDARD; + ret = of_property_read_u32(child, "clock-frequency", &val); + if (!ret) { + if (val == I2C_MAX_FAST_MODE_FREQ) + master->mode = I2C_MODE_FAST; + else if (val == I2C_MAX_FAST_MODE_PLUS_FREQ) + master->mode = I2C_MODE_FAST_PLUS; + } + + init_completion(&master->irq_complete); + } + + /* Memory */ + + cci->base = devm_platform_get_and_ioremap_resource(pdev, 0, &r); + if (IS_ERR(cci->base)) + return PTR_ERR(cci->base); + + /* Clocks */ + + ret = devm_clk_bulk_get_all(dev, &cci->clocks); + if (ret < 0) + return dev_err_probe(dev, ret, "failed to get clocks\n"); + else if (!ret) + return dev_err_probe(dev, -EINVAL, "not enough clocks in DT\n"); + cci->nclocks = ret; + + /* Retrieve CCI clock rate */ + for (i = 0; i < cci->nclocks; i++) { + if (!strcmp(cci->clocks[i].id, "cci")) { + cci_clk_rate = clk_get_rate(cci->clocks[i].clk); + break; + } + } + + if (cci_clk_rate != cci->data->cci_clk_rate) { + /* cci clock set by the bootloader or via assigned clock rate + * in DT. + */ + dev_warn(dev, "Found %lu cci clk rate while %lu was expected\n", + cci_clk_rate, cci->data->cci_clk_rate); + } + + ret = cci_enable_clocks(cci); + if (ret < 0) + return ret; + + /* Interrupt */ + + ret = platform_get_irq(pdev, 0); + if (ret < 0) + goto disable_clocks; + cci->irq = ret; + + ret = devm_request_irq(dev, cci->irq, cci_isr, 0, dev_name(dev), cci); + if (ret < 0) { + dev_err(dev, "request_irq failed, ret: %d\n", ret); + goto disable_clocks; + } + + val = readl(cci->base + CCI_HW_VERSION); + dev_dbg(dev, "CCI HW version = 0x%08x", val); + + ret = cci_reset(cci); + if (ret < 0) + goto error; + + ret = cci_init(cci); + if (ret < 0) + goto error; + + pm_runtime_set_autosuspend_delay(dev, MSEC_PER_SEC); + pm_runtime_use_autosuspend(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); + + for (i = 0; i < cci->data->num_masters; i++) { + if (!cci->master[i].cci) + continue; + + ret = i2c_add_adapter(&cci->master[i].adap); + if (ret < 0) { + of_node_put(cci->master[i].adap.dev.of_node); + goto error_i2c; + } + } + + return 0; + +error_i2c: + pm_runtime_disable(dev); + pm_runtime_dont_use_autosuspend(dev); + + for (--i ; i >= 0; i--) { + if (cci->master[i].cci) { + i2c_del_adapter(&cci->master[i].adap); + of_node_put(cci->master[i].adap.dev.of_node); + } + } +error: + disable_irq(cci->irq); +disable_clocks: + cci_disable_clocks(cci); + + return ret; +} + +static void cci_remove(struct platform_device *pdev) +{ + struct cci *cci = platform_get_drvdata(pdev); + int i; + + for (i = 0; i < cci->data->num_masters; i++) { + if (cci->master[i].cci) { + i2c_del_adapter(&cci->master[i].adap); + of_node_put(cci->master[i].adap.dev.of_node); + } + cci_halt(cci, i); + } + + disable_irq(cci->irq); + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); +} + +static const struct cci_data cci_v1_data = { + .num_masters = 1, + .queue_size = { 64, 16 }, + .quirks = { + .max_write_len = 10, + .max_read_len = 12, + }, + .cci_clk_rate = 19200000, + .params[I2C_MODE_STANDARD] = { + .thigh = 78, + .tlow = 114, + .tsu_sto = 28, + .tsu_sta = 28, + .thd_dat = 10, + .thd_sta = 77, + .tbuf = 118, + .scl_stretch_en = 0, + .trdhld = 6, + .tsp = 1 + }, + .params[I2C_MODE_FAST] = { + .thigh = 20, + .tlow = 28, + .tsu_sto = 21, + .tsu_sta = 21, + .thd_dat = 13, + .thd_sta = 18, + .tbuf = 32, + .scl_stretch_en = 0, + .trdhld = 6, + .tsp = 3 + }, +}; + +static const struct cci_data cci_v1_5_data = { + .num_masters = 2, + .queue_size = { 64, 16 }, + .quirks = { + .max_write_len = 10, + .max_read_len = 12, + }, + .cci_clk_rate = 19200000, + .params[I2C_MODE_STANDARD] = { + .thigh = 78, + .tlow = 114, + .tsu_sto = 28, + .tsu_sta = 28, + .thd_dat = 10, + .thd_sta = 77, + .tbuf = 118, + .scl_stretch_en = 0, + .trdhld = 6, + .tsp = 1 + }, + .params[I2C_MODE_FAST] = { + .thigh = 20, + .tlow = 28, + .tsu_sto = 21, + .tsu_sta = 21, + .thd_dat = 13, + .thd_sta = 18, + .tbuf = 32, + .scl_stretch_en = 0, + .trdhld = 6, + .tsp = 3 + }, +}; + +static const struct cci_data cci_v2_data = { + .num_masters = 2, + .queue_size = { 64, 16 }, + .quirks = { + .max_write_len = 11, + .max_read_len = 12, + }, + .cci_clk_rate = 37500000, + .params[I2C_MODE_STANDARD] = { + .thigh = 201, + .tlow = 174, + .tsu_sto = 204, + .tsu_sta = 231, + .thd_dat = 22, + .thd_sta = 162, + .tbuf = 227, + .scl_stretch_en = 0, + .trdhld = 6, + .tsp = 3 + }, + .params[I2C_MODE_FAST] = { + .thigh = 38, + .tlow = 56, + .tsu_sto = 40, + .tsu_sta = 40, + .thd_dat = 22, + .thd_sta = 35, + .tbuf = 62, + .scl_stretch_en = 0, + .trdhld = 6, + .tsp = 3 + }, + .params[I2C_MODE_FAST_PLUS] = { + .thigh = 16, + .tlow = 22, + .tsu_sto = 17, + .tsu_sta = 18, + .thd_dat = 16, + .thd_sta = 15, + .tbuf = 24, + .scl_stretch_en = 0, + .trdhld = 3, + .tsp = 3 + }, +}; + +static const struct of_device_id cci_dt_match[] = { + { .compatible = "qcom,msm8226-cci", .data = &cci_v1_data}, + { .compatible = "qcom,msm8974-cci", .data = &cci_v1_5_data}, + { .compatible = "qcom,msm8996-cci", .data = &cci_v2_data}, + + + /* + * Legacy compatibles kept for backwards compatibility. + * Do not add any new ones unless they introduce a new config + */ + { .compatible = "qcom,msm8916-cci", .data = &cci_v1_data}, + { .compatible = "qcom,sdm845-cci", .data = &cci_v2_data}, + { .compatible = "qcom,sm8250-cci", .data = &cci_v2_data}, + { .compatible = "qcom,sm8450-cci", .data = &cci_v2_data}, + {} +}; +MODULE_DEVICE_TABLE(of, cci_dt_match); + +static struct platform_driver qcom_cci_driver = { + .probe = cci_probe, + .remove_new = cci_remove, + .driver = { + .name = "i2c-qcom-cci", + .of_match_table = cci_dt_match, + .pm = &qcom_cci_pm, + }, +}; + +module_platform_driver(qcom_cci_driver); + +MODULE_DESCRIPTION("Qualcomm Camera Control Interface driver"); +MODULE_AUTHOR("Todor Tomov <todor.tomov@linaro.org>"); +MODULE_AUTHOR("Loic Poulain <loic.poulain@linaro.org>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c new file mode 100644 index 000000000..0a9d389df --- /dev/null +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -0,0 +1,1060 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2017-2018, The Linux Foundation. All rights reserved. + +#include <linux/acpi.h> +#include <linux/clk.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/dma/qcom-gpi-dma.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/soc/qcom/geni-se.h> +#include <linux/spinlock.h> + +#define SE_I2C_TX_TRANS_LEN 0x26c +#define SE_I2C_RX_TRANS_LEN 0x270 +#define SE_I2C_SCL_COUNTERS 0x278 + +#define SE_I2C_ERR (M_CMD_OVERRUN_EN | M_ILLEGAL_CMD_EN | M_CMD_FAILURE_EN |\ + M_GP_IRQ_1_EN | M_GP_IRQ_3_EN | M_GP_IRQ_4_EN) +#define SE_I2C_ABORT BIT(1) + +/* M_CMD OP codes for I2C */ +#define I2C_WRITE 0x1 +#define I2C_READ 0x2 +#define I2C_WRITE_READ 0x3 +#define I2C_ADDR_ONLY 0x4 +#define I2C_BUS_CLEAR 0x6 +#define I2C_STOP_ON_BUS 0x7 +/* M_CMD params for I2C */ +#define PRE_CMD_DELAY BIT(0) +#define TIMESTAMP_BEFORE BIT(1) +#define STOP_STRETCH BIT(2) +#define TIMESTAMP_AFTER BIT(3) +#define POST_COMMAND_DELAY BIT(4) +#define IGNORE_ADD_NACK BIT(6) +#define READ_FINISHED_WITH_ACK BIT(7) +#define BYPASS_ADDR_PHASE BIT(8) +#define SLV_ADDR_MSK GENMASK(15, 9) +#define SLV_ADDR_SHFT 9 +/* I2C SCL COUNTER fields */ +#define HIGH_COUNTER_MSK GENMASK(29, 20) +#define HIGH_COUNTER_SHFT 20 +#define LOW_COUNTER_MSK GENMASK(19, 10) +#define LOW_COUNTER_SHFT 10 +#define CYCLE_COUNTER_MSK GENMASK(9, 0) + +#define I2C_PACK_TX BIT(0) +#define I2C_PACK_RX BIT(1) + +enum geni_i2c_err_code { + GP_IRQ0, + NACK, + GP_IRQ2, + BUS_PROTO, + ARB_LOST, + GP_IRQ5, + GENI_OVERRUN, + GENI_ILLEGAL_CMD, + GENI_ABORT_DONE, + GENI_TIMEOUT, +}; + +#define DM_I2C_CB_ERR ((BIT(NACK) | BIT(BUS_PROTO) | BIT(ARB_LOST)) \ + << 5) + +#define I2C_AUTO_SUSPEND_DELAY 250 +#define KHZ(freq) (1000 * freq) +#define PACKING_BYTES_PW 4 + +#define ABORT_TIMEOUT HZ +#define XFER_TIMEOUT HZ +#define RST_TIMEOUT HZ + +struct geni_i2c_dev { + struct geni_se se; + u32 tx_wm; + int irq; + int err; + struct i2c_adapter adap; + struct completion done; + struct i2c_msg *cur; + int cur_wr; + int cur_rd; + spinlock_t lock; + struct clk *core_clk; + u32 clk_freq_out; + const struct geni_i2c_clk_fld *clk_fld; + int suspended; + void *dma_buf; + size_t xfer_len; + dma_addr_t dma_addr; + struct dma_chan *tx_c; + struct dma_chan *rx_c; + bool gpi_mode; + bool abort_done; +}; + +struct geni_i2c_desc { + bool has_core_clk; + char *icc_ddr; + bool no_dma_support; + unsigned int tx_fifo_depth; +}; + +struct geni_i2c_err_log { + int err; + const char *msg; +}; + +static const struct geni_i2c_err_log gi2c_log[] = { + [GP_IRQ0] = {-EIO, "Unknown I2C err GP_IRQ0"}, + [NACK] = {-ENXIO, "NACK: slv unresponsive, check its power/reset-ln"}, + [GP_IRQ2] = {-EIO, "Unknown I2C err GP IRQ2"}, + [BUS_PROTO] = {-EPROTO, "Bus proto err, noisy/unexpected start/stop"}, + [ARB_LOST] = {-EAGAIN, "Bus arbitration lost, clock line undriveable"}, + [GP_IRQ5] = {-EIO, "Unknown I2C err GP IRQ5"}, + [GENI_OVERRUN] = {-EIO, "Cmd overrun, check GENI cmd-state machine"}, + [GENI_ILLEGAL_CMD] = {-EIO, "Illegal cmd, check GENI cmd-state machine"}, + [GENI_ABORT_DONE] = {-ETIMEDOUT, "Abort after timeout successful"}, + [GENI_TIMEOUT] = {-ETIMEDOUT, "I2C TXN timed out"}, +}; + +struct geni_i2c_clk_fld { + u32 clk_freq_out; + u8 clk_div; + u8 t_high_cnt; + u8 t_low_cnt; + u8 t_cycle_cnt; +}; + +/* + * Hardware uses the underlying formula to calculate time periods of + * SCL clock cycle. Firmware uses some additional cycles excluded from the + * below formula and it is confirmed that the time periods are within + * specification limits. + * + * time of high period of SCL: t_high = (t_high_cnt * clk_div) / source_clock + * time of low period of SCL: t_low = (t_low_cnt * clk_div) / source_clock + * time of full period of SCL: t_cycle = (t_cycle_cnt * clk_div) / source_clock + * clk_freq_out = t / t_cycle + * source_clock = 19.2 MHz + */ +static const struct geni_i2c_clk_fld geni_i2c_clk_map[] = { + {KHZ(100), 7, 10, 11, 26}, + {KHZ(400), 2, 5, 12, 24}, + {KHZ(1000), 1, 3, 9, 18}, +}; + +static int geni_i2c_clk_map_idx(struct geni_i2c_dev *gi2c) +{ + int i; + const struct geni_i2c_clk_fld *itr = geni_i2c_clk_map; + + for (i = 0; i < ARRAY_SIZE(geni_i2c_clk_map); i++, itr++) { + if (itr->clk_freq_out == gi2c->clk_freq_out) { + gi2c->clk_fld = itr; + return 0; + } + } + return -EINVAL; +} + +static void qcom_geni_i2c_conf(struct geni_i2c_dev *gi2c) +{ + const struct geni_i2c_clk_fld *itr = gi2c->clk_fld; + u32 val; + + writel_relaxed(0, gi2c->se.base + SE_GENI_CLK_SEL); + + val = (itr->clk_div << CLK_DIV_SHFT) | SER_CLK_EN; + writel_relaxed(val, gi2c->se.base + GENI_SER_M_CLK_CFG); + + val = itr->t_high_cnt << HIGH_COUNTER_SHFT; + val |= itr->t_low_cnt << LOW_COUNTER_SHFT; + val |= itr->t_cycle_cnt; + writel_relaxed(val, gi2c->se.base + SE_I2C_SCL_COUNTERS); +} + +static void geni_i2c_err_misc(struct geni_i2c_dev *gi2c) +{ + u32 m_cmd = readl_relaxed(gi2c->se.base + SE_GENI_M_CMD0); + u32 m_stat = readl_relaxed(gi2c->se.base + SE_GENI_M_IRQ_STATUS); + u32 geni_s = readl_relaxed(gi2c->se.base + SE_GENI_STATUS); + u32 geni_ios = readl_relaxed(gi2c->se.base + SE_GENI_IOS); + u32 dma = readl_relaxed(gi2c->se.base + SE_GENI_DMA_MODE_EN); + u32 rx_st, tx_st; + + if (dma) { + rx_st = readl_relaxed(gi2c->se.base + SE_DMA_RX_IRQ_STAT); + tx_st = readl_relaxed(gi2c->se.base + SE_DMA_TX_IRQ_STAT); + } else { + rx_st = readl_relaxed(gi2c->se.base + SE_GENI_RX_FIFO_STATUS); + tx_st = readl_relaxed(gi2c->se.base + SE_GENI_TX_FIFO_STATUS); + } + dev_dbg(gi2c->se.dev, "DMA:%d tx_stat:0x%x, rx_stat:0x%x, irq-stat:0x%x\n", + dma, tx_st, rx_st, m_stat); + dev_dbg(gi2c->se.dev, "m_cmd:0x%x, geni_status:0x%x, geni_ios:0x%x\n", + m_cmd, geni_s, geni_ios); +} + +static void geni_i2c_err(struct geni_i2c_dev *gi2c, int err) +{ + if (!gi2c->err) + gi2c->err = gi2c_log[err].err; + if (gi2c->cur) + dev_dbg(gi2c->se.dev, "len:%d, slv-addr:0x%x, RD/WR:%d\n", + gi2c->cur->len, gi2c->cur->addr, gi2c->cur->flags); + + switch (err) { + case GENI_ABORT_DONE: + gi2c->abort_done = true; + break; + case NACK: + case GENI_TIMEOUT: + dev_dbg(gi2c->se.dev, "%s\n", gi2c_log[err].msg); + break; + default: + dev_err(gi2c->se.dev, "%s\n", gi2c_log[err].msg); + geni_i2c_err_misc(gi2c); + break; + } +} + +static irqreturn_t geni_i2c_irq(int irq, void *dev) +{ + struct geni_i2c_dev *gi2c = dev; + void __iomem *base = gi2c->se.base; + int j, p; + u32 m_stat; + u32 rx_st; + u32 dm_tx_st; + u32 dm_rx_st; + u32 dma; + u32 val; + struct i2c_msg *cur; + + spin_lock(&gi2c->lock); + m_stat = readl_relaxed(base + SE_GENI_M_IRQ_STATUS); + rx_st = readl_relaxed(base + SE_GENI_RX_FIFO_STATUS); + dm_tx_st = readl_relaxed(base + SE_DMA_TX_IRQ_STAT); + dm_rx_st = readl_relaxed(base + SE_DMA_RX_IRQ_STAT); + dma = readl_relaxed(base + SE_GENI_DMA_MODE_EN); + cur = gi2c->cur; + + if (!cur || + m_stat & (M_CMD_FAILURE_EN | M_CMD_ABORT_EN) || + dm_rx_st & (DM_I2C_CB_ERR)) { + if (m_stat & M_GP_IRQ_1_EN) + geni_i2c_err(gi2c, NACK); + if (m_stat & M_GP_IRQ_3_EN) + geni_i2c_err(gi2c, BUS_PROTO); + if (m_stat & M_GP_IRQ_4_EN) + geni_i2c_err(gi2c, ARB_LOST); + if (m_stat & M_CMD_OVERRUN_EN) + geni_i2c_err(gi2c, GENI_OVERRUN); + if (m_stat & M_ILLEGAL_CMD_EN) + geni_i2c_err(gi2c, GENI_ILLEGAL_CMD); + if (m_stat & M_CMD_ABORT_EN) + geni_i2c_err(gi2c, GENI_ABORT_DONE); + if (m_stat & M_GP_IRQ_0_EN) + geni_i2c_err(gi2c, GP_IRQ0); + + /* Disable the TX Watermark interrupt to stop TX */ + if (!dma) + writel_relaxed(0, base + SE_GENI_TX_WATERMARK_REG); + } else if (dma) { + dev_dbg(gi2c->se.dev, "i2c dma tx:0x%x, dma rx:0x%x\n", + dm_tx_st, dm_rx_st); + } else if (cur->flags & I2C_M_RD && + m_stat & (M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN)) { + u32 rxcnt = rx_st & RX_FIFO_WC_MSK; + + for (j = 0; j < rxcnt; j++) { + p = 0; + val = readl_relaxed(base + SE_GENI_RX_FIFOn); + while (gi2c->cur_rd < cur->len && p < sizeof(val)) { + cur->buf[gi2c->cur_rd++] = val & 0xff; + val >>= 8; + p++; + } + if (gi2c->cur_rd == cur->len) + break; + } + } else if (!(cur->flags & I2C_M_RD) && + m_stat & M_TX_FIFO_WATERMARK_EN) { + for (j = 0; j < gi2c->tx_wm; j++) { + u32 temp; + + val = 0; + p = 0; + while (gi2c->cur_wr < cur->len && p < sizeof(val)) { + temp = cur->buf[gi2c->cur_wr++]; + val |= temp << (p * 8); + p++; + } + writel_relaxed(val, base + SE_GENI_TX_FIFOn); + /* TX Complete, Disable the TX Watermark interrupt */ + if (gi2c->cur_wr == cur->len) { + writel_relaxed(0, base + SE_GENI_TX_WATERMARK_REG); + break; + } + } + } + + if (m_stat) + writel_relaxed(m_stat, base + SE_GENI_M_IRQ_CLEAR); + + if (dma && dm_tx_st) + writel_relaxed(dm_tx_st, base + SE_DMA_TX_IRQ_CLR); + if (dma && dm_rx_st) + writel_relaxed(dm_rx_st, base + SE_DMA_RX_IRQ_CLR); + + /* if this is err with done-bit not set, handle that through timeout. */ + if (m_stat & M_CMD_DONE_EN || m_stat & M_CMD_ABORT_EN || + dm_tx_st & TX_DMA_DONE || dm_tx_st & TX_RESET_DONE || + dm_rx_st & RX_DMA_DONE || dm_rx_st & RX_RESET_DONE) + complete(&gi2c->done); + + spin_unlock(&gi2c->lock); + + return IRQ_HANDLED; +} + +static void geni_i2c_abort_xfer(struct geni_i2c_dev *gi2c) +{ + unsigned long time_left = ABORT_TIMEOUT; + unsigned long flags; + + spin_lock_irqsave(&gi2c->lock, flags); + geni_i2c_err(gi2c, GENI_TIMEOUT); + gi2c->cur = NULL; + gi2c->abort_done = false; + geni_se_abort_m_cmd(&gi2c->se); + spin_unlock_irqrestore(&gi2c->lock, flags); + + do { + time_left = wait_for_completion_timeout(&gi2c->done, time_left); + } while (!gi2c->abort_done && time_left); + + if (!time_left) + dev_err(gi2c->se.dev, "Timeout abort_m_cmd\n"); +} + +static void geni_i2c_rx_fsm_rst(struct geni_i2c_dev *gi2c) +{ + u32 val; + unsigned long time_left = RST_TIMEOUT; + + writel_relaxed(1, gi2c->se.base + SE_DMA_RX_FSM_RST); + do { + time_left = wait_for_completion_timeout(&gi2c->done, time_left); + val = readl_relaxed(gi2c->se.base + SE_DMA_RX_IRQ_STAT); + } while (!(val & RX_RESET_DONE) && time_left); + + if (!(val & RX_RESET_DONE)) + dev_err(gi2c->se.dev, "Timeout resetting RX_FSM\n"); +} + +static void geni_i2c_tx_fsm_rst(struct geni_i2c_dev *gi2c) +{ + u32 val; + unsigned long time_left = RST_TIMEOUT; + + writel_relaxed(1, gi2c->se.base + SE_DMA_TX_FSM_RST); + do { + time_left = wait_for_completion_timeout(&gi2c->done, time_left); + val = readl_relaxed(gi2c->se.base + SE_DMA_TX_IRQ_STAT); + } while (!(val & TX_RESET_DONE) && time_left); + + if (!(val & TX_RESET_DONE)) + dev_err(gi2c->se.dev, "Timeout resetting TX_FSM\n"); +} + +static void geni_i2c_rx_msg_cleanup(struct geni_i2c_dev *gi2c, + struct i2c_msg *cur) +{ + gi2c->cur_rd = 0; + if (gi2c->dma_buf) { + if (gi2c->err) + geni_i2c_rx_fsm_rst(gi2c); + geni_se_rx_dma_unprep(&gi2c->se, gi2c->dma_addr, gi2c->xfer_len); + i2c_put_dma_safe_msg_buf(gi2c->dma_buf, cur, !gi2c->err); + } +} + +static void geni_i2c_tx_msg_cleanup(struct geni_i2c_dev *gi2c, + struct i2c_msg *cur) +{ + gi2c->cur_wr = 0; + if (gi2c->dma_buf) { + if (gi2c->err) + geni_i2c_tx_fsm_rst(gi2c); + geni_se_tx_dma_unprep(&gi2c->se, gi2c->dma_addr, gi2c->xfer_len); + i2c_put_dma_safe_msg_buf(gi2c->dma_buf, cur, !gi2c->err); + } +} + +static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, + u32 m_param) +{ + dma_addr_t rx_dma = 0; + unsigned long time_left; + void *dma_buf; + struct geni_se *se = &gi2c->se; + size_t len = msg->len; + struct i2c_msg *cur; + + dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); + if (dma_buf) + geni_se_select_mode(se, GENI_SE_DMA); + else + geni_se_select_mode(se, GENI_SE_FIFO); + + writel_relaxed(len, se->base + SE_I2C_RX_TRANS_LEN); + geni_se_setup_m_cmd(se, I2C_READ, m_param); + + if (dma_buf && geni_se_rx_dma_prep(se, dma_buf, len, &rx_dma)) { + geni_se_select_mode(se, GENI_SE_FIFO); + i2c_put_dma_safe_msg_buf(dma_buf, msg, false); + dma_buf = NULL; + } else { + gi2c->xfer_len = len; + gi2c->dma_addr = rx_dma; + gi2c->dma_buf = dma_buf; + } + + cur = gi2c->cur; + time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT); + if (!time_left) + geni_i2c_abort_xfer(gi2c); + + geni_i2c_rx_msg_cleanup(gi2c, cur); + + return gi2c->err; +} + +static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, + u32 m_param) +{ + dma_addr_t tx_dma = 0; + unsigned long time_left; + void *dma_buf; + struct geni_se *se = &gi2c->se; + size_t len = msg->len; + struct i2c_msg *cur; + + dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); + if (dma_buf) + geni_se_select_mode(se, GENI_SE_DMA); + else + geni_se_select_mode(se, GENI_SE_FIFO); + + writel_relaxed(len, se->base + SE_I2C_TX_TRANS_LEN); + geni_se_setup_m_cmd(se, I2C_WRITE, m_param); + + if (dma_buf && geni_se_tx_dma_prep(se, dma_buf, len, &tx_dma)) { + geni_se_select_mode(se, GENI_SE_FIFO); + i2c_put_dma_safe_msg_buf(dma_buf, msg, false); + dma_buf = NULL; + } else { + gi2c->xfer_len = len; + gi2c->dma_addr = tx_dma; + gi2c->dma_buf = dma_buf; + } + + if (!dma_buf) /* Get FIFO IRQ */ + writel_relaxed(1, se->base + SE_GENI_TX_WATERMARK_REG); + + cur = gi2c->cur; + time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT); + if (!time_left) + geni_i2c_abort_xfer(gi2c); + + geni_i2c_tx_msg_cleanup(gi2c, cur); + + return gi2c->err; +} + +static void i2c_gpi_cb_result(void *cb, const struct dmaengine_result *result) +{ + struct geni_i2c_dev *gi2c = cb; + + if (result->result != DMA_TRANS_NOERROR) { + dev_err(gi2c->se.dev, "DMA txn failed:%d\n", result->result); + gi2c->err = -EIO; + } else if (result->residue) { + dev_dbg(gi2c->se.dev, "DMA xfer has pending: %d\n", result->residue); + } + + complete(&gi2c->done); +} + +static void geni_i2c_gpi_unmap(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, + void *tx_buf, dma_addr_t tx_addr, + void *rx_buf, dma_addr_t rx_addr) +{ + if (tx_buf) { + dma_unmap_single(gi2c->se.dev->parent, tx_addr, msg->len, DMA_TO_DEVICE); + i2c_put_dma_safe_msg_buf(tx_buf, msg, !gi2c->err); + } + + if (rx_buf) { + dma_unmap_single(gi2c->se.dev->parent, rx_addr, msg->len, DMA_FROM_DEVICE); + i2c_put_dma_safe_msg_buf(rx_buf, msg, !gi2c->err); + } +} + +static int geni_i2c_gpi(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, + struct dma_slave_config *config, dma_addr_t *dma_addr_p, + void **buf, unsigned int op, struct dma_chan *dma_chan) +{ + struct gpi_i2c_config *peripheral; + unsigned int flags; + void *dma_buf; + dma_addr_t addr; + enum dma_data_direction map_dirn; + enum dma_transfer_direction dma_dirn; + struct dma_async_tx_descriptor *desc; + int ret; + + peripheral = config->peripheral_config; + + dma_buf = i2c_get_dma_safe_msg_buf(msg, 1); + if (!dma_buf) + return -ENOMEM; + + if (op == I2C_WRITE) + map_dirn = DMA_TO_DEVICE; + else + map_dirn = DMA_FROM_DEVICE; + + addr = dma_map_single(gi2c->se.dev->parent, dma_buf, msg->len, map_dirn); + if (dma_mapping_error(gi2c->se.dev->parent, addr)) { + i2c_put_dma_safe_msg_buf(dma_buf, msg, false); + return -ENOMEM; + } + + /* set the length as message for rx txn */ + peripheral->rx_len = msg->len; + peripheral->op = op; + + ret = dmaengine_slave_config(dma_chan, config); + if (ret) { + dev_err(gi2c->se.dev, "dma config error: %d for op:%d\n", ret, op); + goto err_config; + } + + peripheral->set_config = 0; + peripheral->multi_msg = true; + flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK; + + if (op == I2C_WRITE) + dma_dirn = DMA_MEM_TO_DEV; + else + dma_dirn = DMA_DEV_TO_MEM; + + desc = dmaengine_prep_slave_single(dma_chan, addr, msg->len, dma_dirn, flags); + if (!desc) { + dev_err(gi2c->se.dev, "prep_slave_sg failed\n"); + ret = -EIO; + goto err_config; + } + + desc->callback_result = i2c_gpi_cb_result; + desc->callback_param = gi2c; + + dmaengine_submit(desc); + *buf = dma_buf; + *dma_addr_p = addr; + + return 0; + +err_config: + dma_unmap_single(gi2c->se.dev->parent, addr, msg->len, map_dirn); + i2c_put_dma_safe_msg_buf(dma_buf, msg, false); + return ret; +} + +static int geni_i2c_gpi_xfer(struct geni_i2c_dev *gi2c, struct i2c_msg msgs[], int num) +{ + struct dma_slave_config config = {}; + struct gpi_i2c_config peripheral = {}; + int i, ret = 0, timeout; + dma_addr_t tx_addr, rx_addr; + void *tx_buf = NULL, *rx_buf = NULL; + const struct geni_i2c_clk_fld *itr = gi2c->clk_fld; + + config.peripheral_config = &peripheral; + config.peripheral_size = sizeof(peripheral); + + peripheral.pack_enable = I2C_PACK_TX | I2C_PACK_RX; + peripheral.cycle_count = itr->t_cycle_cnt; + peripheral.high_count = itr->t_high_cnt; + peripheral.low_count = itr->t_low_cnt; + peripheral.clk_div = itr->clk_div; + peripheral.set_config = 1; + peripheral.multi_msg = false; + + for (i = 0; i < num; i++) { + gi2c->cur = &msgs[i]; + gi2c->err = 0; + dev_dbg(gi2c->se.dev, "msg[%d].len:%d\n", i, gi2c->cur->len); + + peripheral.stretch = 0; + if (i < num - 1) + peripheral.stretch = 1; + + peripheral.addr = msgs[i].addr; + + if (msgs[i].flags & I2C_M_RD) { + ret = geni_i2c_gpi(gi2c, &msgs[i], &config, + &rx_addr, &rx_buf, I2C_READ, gi2c->rx_c); + if (ret) + goto err; + } + + ret = geni_i2c_gpi(gi2c, &msgs[i], &config, + &tx_addr, &tx_buf, I2C_WRITE, gi2c->tx_c); + if (ret) + goto err; + + if (msgs[i].flags & I2C_M_RD) + dma_async_issue_pending(gi2c->rx_c); + dma_async_issue_pending(gi2c->tx_c); + + timeout = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT); + if (!timeout) { + dev_err(gi2c->se.dev, "I2C timeout gpi flags:%d addr:0x%x\n", + gi2c->cur->flags, gi2c->cur->addr); + gi2c->err = -ETIMEDOUT; + } + + if (gi2c->err) { + ret = gi2c->err; + goto err; + } + + geni_i2c_gpi_unmap(gi2c, &msgs[i], tx_buf, tx_addr, rx_buf, rx_addr); + } + + return num; + +err: + dev_err(gi2c->se.dev, "GPI transfer failed: %d\n", ret); + dmaengine_terminate_sync(gi2c->rx_c); + dmaengine_terminate_sync(gi2c->tx_c); + geni_i2c_gpi_unmap(gi2c, &msgs[i], tx_buf, tx_addr, rx_buf, rx_addr); + return ret; +} + +static int geni_i2c_fifo_xfer(struct geni_i2c_dev *gi2c, + struct i2c_msg msgs[], int num) +{ + int i, ret = 0; + + for (i = 0; i < num; i++) { + u32 m_param = i < (num - 1) ? STOP_STRETCH : 0; + + m_param |= ((msgs[i].addr << SLV_ADDR_SHFT) & SLV_ADDR_MSK); + + gi2c->cur = &msgs[i]; + if (msgs[i].flags & I2C_M_RD) + ret = geni_i2c_rx_one_msg(gi2c, &msgs[i], m_param); + else + ret = geni_i2c_tx_one_msg(gi2c, &msgs[i], m_param); + + if (ret) + return ret; + } + + return num; +} + +static int geni_i2c_xfer(struct i2c_adapter *adap, + struct i2c_msg msgs[], + int num) +{ + struct geni_i2c_dev *gi2c = i2c_get_adapdata(adap); + int ret; + + gi2c->err = 0; + reinit_completion(&gi2c->done); + ret = pm_runtime_get_sync(gi2c->se.dev); + if (ret < 0) { + dev_err(gi2c->se.dev, "error turning SE resources:%d\n", ret); + pm_runtime_put_noidle(gi2c->se.dev); + /* Set device in suspended since resume failed */ + pm_runtime_set_suspended(gi2c->se.dev); + return ret; + } + + qcom_geni_i2c_conf(gi2c); + + if (gi2c->gpi_mode) + ret = geni_i2c_gpi_xfer(gi2c, msgs, num); + else + ret = geni_i2c_fifo_xfer(gi2c, msgs, num); + + pm_runtime_mark_last_busy(gi2c->se.dev); + pm_runtime_put_autosuspend(gi2c->se.dev); + gi2c->cur = NULL; + gi2c->err = 0; + return ret; +} + +static u32 geni_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); +} + +static const struct i2c_algorithm geni_i2c_algo = { + .master_xfer = geni_i2c_xfer, + .functionality = geni_i2c_func, +}; + +#ifdef CONFIG_ACPI +static const struct acpi_device_id geni_i2c_acpi_match[] = { + { "QCOM0220"}, + { }, +}; +MODULE_DEVICE_TABLE(acpi, geni_i2c_acpi_match); +#endif + +static void release_gpi_dma(struct geni_i2c_dev *gi2c) +{ + if (gi2c->rx_c) + dma_release_channel(gi2c->rx_c); + + if (gi2c->tx_c) + dma_release_channel(gi2c->tx_c); +} + +static int setup_gpi_dma(struct geni_i2c_dev *gi2c) +{ + int ret; + + geni_se_select_mode(&gi2c->se, GENI_GPI_DMA); + gi2c->tx_c = dma_request_chan(gi2c->se.dev, "tx"); + if (IS_ERR(gi2c->tx_c)) { + ret = dev_err_probe(gi2c->se.dev, PTR_ERR(gi2c->tx_c), + "Failed to get tx DMA ch\n"); + goto err_tx; + } + + gi2c->rx_c = dma_request_chan(gi2c->se.dev, "rx"); + if (IS_ERR(gi2c->rx_c)) { + ret = dev_err_probe(gi2c->se.dev, PTR_ERR(gi2c->rx_c), + "Failed to get rx DMA ch\n"); + goto err_rx; + } + + dev_dbg(gi2c->se.dev, "Grabbed GPI dma channels\n"); + return 0; + +err_rx: + dma_release_channel(gi2c->tx_c); +err_tx: + return ret; +} + +static int geni_i2c_probe(struct platform_device *pdev) +{ + struct geni_i2c_dev *gi2c; + u32 proto, tx_depth, fifo_disable; + int ret; + struct device *dev = &pdev->dev; + const struct geni_i2c_desc *desc = NULL; + + gi2c = devm_kzalloc(dev, sizeof(*gi2c), GFP_KERNEL); + if (!gi2c) + return -ENOMEM; + + gi2c->se.dev = dev; + gi2c->se.wrapper = dev_get_drvdata(dev->parent); + gi2c->se.base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(gi2c->se.base)) + return PTR_ERR(gi2c->se.base); + + desc = device_get_match_data(&pdev->dev); + + if (desc && desc->has_core_clk) { + gi2c->core_clk = devm_clk_get(dev, "core"); + if (IS_ERR(gi2c->core_clk)) + return PTR_ERR(gi2c->core_clk); + } + + gi2c->se.clk = devm_clk_get(dev, "se"); + if (IS_ERR(gi2c->se.clk) && !has_acpi_companion(dev)) + return PTR_ERR(gi2c->se.clk); + + ret = device_property_read_u32(dev, "clock-frequency", + &gi2c->clk_freq_out); + if (ret) { + dev_info(dev, "Bus frequency not specified, default to 100kHz.\n"); + gi2c->clk_freq_out = KHZ(100); + } + + if (has_acpi_companion(dev)) + ACPI_COMPANION_SET(&gi2c->adap.dev, ACPI_COMPANION(dev)); + + gi2c->irq = platform_get_irq(pdev, 0); + if (gi2c->irq < 0) + return gi2c->irq; + + ret = geni_i2c_clk_map_idx(gi2c); + if (ret) { + dev_err(dev, "Invalid clk frequency %d Hz: %d\n", + gi2c->clk_freq_out, ret); + return ret; + } + + gi2c->adap.algo = &geni_i2c_algo; + init_completion(&gi2c->done); + spin_lock_init(&gi2c->lock); + platform_set_drvdata(pdev, gi2c); + ret = devm_request_irq(dev, gi2c->irq, geni_i2c_irq, 0, + dev_name(dev), gi2c); + if (ret) { + dev_err(dev, "Request_irq failed:%d: err:%d\n", + gi2c->irq, ret); + return ret; + } + /* Disable the interrupt so that the system can enter low-power mode */ + disable_irq(gi2c->irq); + i2c_set_adapdata(&gi2c->adap, gi2c); + gi2c->adap.dev.parent = dev; + gi2c->adap.dev.of_node = dev->of_node; + strscpy(gi2c->adap.name, "Geni-I2C", sizeof(gi2c->adap.name)); + + ret = geni_icc_get(&gi2c->se, desc ? desc->icc_ddr : "qup-memory"); + if (ret) + return ret; + /* + * Set the bus quota for core and cpu to a reasonable value for + * register access. + * Set quota for DDR based on bus speed. + */ + gi2c->se.icc_paths[GENI_TO_CORE].avg_bw = GENI_DEFAULT_BW; + gi2c->se.icc_paths[CPU_TO_GENI].avg_bw = GENI_DEFAULT_BW; + if (!desc || desc->icc_ddr) + gi2c->se.icc_paths[GENI_TO_DDR].avg_bw = Bps_to_icc(gi2c->clk_freq_out); + + ret = geni_icc_set_bw(&gi2c->se); + if (ret) + return ret; + + ret = clk_prepare_enable(gi2c->core_clk); + if (ret) + return ret; + + ret = geni_se_resources_on(&gi2c->se); + if (ret) { + dev_err(dev, "Error turning on resources %d\n", ret); + clk_disable_unprepare(gi2c->core_clk); + return ret; + } + proto = geni_se_read_proto(&gi2c->se); + if (proto != GENI_SE_I2C) { + dev_err(dev, "Invalid proto %d\n", proto); + geni_se_resources_off(&gi2c->se); + clk_disable_unprepare(gi2c->core_clk); + return -ENXIO; + } + + if (desc && desc->no_dma_support) + fifo_disable = false; + else + fifo_disable = readl_relaxed(gi2c->se.base + GENI_IF_DISABLE_RO) & FIFO_IF_DISABLE; + + if (fifo_disable) { + /* FIFO is disabled, so we can only use GPI DMA */ + gi2c->gpi_mode = true; + ret = setup_gpi_dma(gi2c); + if (ret) { + geni_se_resources_off(&gi2c->se); + clk_disable_unprepare(gi2c->core_clk); + return dev_err_probe(dev, ret, "Failed to setup GPI DMA mode\n"); + } + + dev_dbg(dev, "Using GPI DMA mode for I2C\n"); + } else { + gi2c->gpi_mode = false; + tx_depth = geni_se_get_tx_fifo_depth(&gi2c->se); + + /* I2C Master Hub Serial Elements doesn't have the HW_PARAM_0 register */ + if (!tx_depth && desc) + tx_depth = desc->tx_fifo_depth; + + if (!tx_depth) { + dev_err(dev, "Invalid TX FIFO depth\n"); + geni_se_resources_off(&gi2c->se); + clk_disable_unprepare(gi2c->core_clk); + return -EINVAL; + } + + gi2c->tx_wm = tx_depth - 1; + geni_se_init(&gi2c->se, gi2c->tx_wm, tx_depth); + geni_se_config_packing(&gi2c->se, BITS_PER_BYTE, + PACKING_BYTES_PW, true, true, true); + + dev_dbg(dev, "i2c fifo/se-dma mode. fifo depth:%d\n", tx_depth); + } + + clk_disable_unprepare(gi2c->core_clk); + ret = geni_se_resources_off(&gi2c->se); + if (ret) { + dev_err(dev, "Error turning off resources %d\n", ret); + goto err_dma; + } + + ret = geni_icc_disable(&gi2c->se); + if (ret) + goto err_dma; + + gi2c->suspended = 1; + pm_runtime_set_suspended(gi2c->se.dev); + pm_runtime_set_autosuspend_delay(gi2c->se.dev, I2C_AUTO_SUSPEND_DELAY); + pm_runtime_use_autosuspend(gi2c->se.dev); + pm_runtime_enable(gi2c->se.dev); + + ret = i2c_add_adapter(&gi2c->adap); + if (ret) { + dev_err(dev, "Error adding i2c adapter %d\n", ret); + pm_runtime_disable(gi2c->se.dev); + goto err_dma; + } + + dev_dbg(dev, "Geni-I2C adaptor successfully added\n"); + + return 0; + +err_dma: + release_gpi_dma(gi2c); + return ret; +} + +static void geni_i2c_remove(struct platform_device *pdev) +{ + struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&gi2c->adap); + release_gpi_dma(gi2c); + pm_runtime_disable(gi2c->se.dev); +} + +static void geni_i2c_shutdown(struct platform_device *pdev) +{ + struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev); + + /* Make client i2c transfers start failing */ + i2c_mark_adapter_suspended(&gi2c->adap); +} + +static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev) +{ + int ret; + struct geni_i2c_dev *gi2c = dev_get_drvdata(dev); + + disable_irq(gi2c->irq); + ret = geni_se_resources_off(&gi2c->se); + if (ret) { + enable_irq(gi2c->irq); + return ret; + + } else { + gi2c->suspended = 1; + } + + clk_disable_unprepare(gi2c->core_clk); + + return geni_icc_disable(&gi2c->se); +} + +static int __maybe_unused geni_i2c_runtime_resume(struct device *dev) +{ + int ret; + struct geni_i2c_dev *gi2c = dev_get_drvdata(dev); + + ret = geni_icc_enable(&gi2c->se); + if (ret) + return ret; + + ret = clk_prepare_enable(gi2c->core_clk); + if (ret) + return ret; + + ret = geni_se_resources_on(&gi2c->se); + if (ret) + return ret; + + enable_irq(gi2c->irq); + gi2c->suspended = 0; + return 0; +} + +static int __maybe_unused geni_i2c_suspend_noirq(struct device *dev) +{ + struct geni_i2c_dev *gi2c = dev_get_drvdata(dev); + + i2c_mark_adapter_suspended(&gi2c->adap); + + if (!gi2c->suspended) { + geni_i2c_runtime_suspend(dev); + pm_runtime_disable(dev); + pm_runtime_set_suspended(dev); + pm_runtime_enable(dev); + } + return 0; +} + +static int __maybe_unused geni_i2c_resume_noirq(struct device *dev) +{ + struct geni_i2c_dev *gi2c = dev_get_drvdata(dev); + + i2c_mark_adapter_resumed(&gi2c->adap); + return 0; +} + +static const struct dev_pm_ops geni_i2c_pm_ops = { + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(geni_i2c_suspend_noirq, geni_i2c_resume_noirq) + SET_RUNTIME_PM_OPS(geni_i2c_runtime_suspend, geni_i2c_runtime_resume, + NULL) +}; + +static const struct geni_i2c_desc i2c_master_hub = { + .has_core_clk = true, + .icc_ddr = NULL, + .no_dma_support = true, + .tx_fifo_depth = 16, +}; + +static const struct of_device_id geni_i2c_dt_match[] = { + { .compatible = "qcom,geni-i2c" }, + { .compatible = "qcom,geni-i2c-master-hub", .data = &i2c_master_hub }, + {} +}; +MODULE_DEVICE_TABLE(of, geni_i2c_dt_match); + +static struct platform_driver geni_i2c_driver = { + .probe = geni_i2c_probe, + .remove_new = geni_i2c_remove, + .shutdown = geni_i2c_shutdown, + .driver = { + .name = "geni_i2c", + .pm = &geni_i2c_pm_ops, + .of_match_table = geni_i2c_dt_match, + .acpi_match_table = ACPI_PTR(geni_i2c_acpi_match), + }, +}; + +module_platform_driver(geni_i2c_driver); + +MODULE_DESCRIPTION("I2C Controller Driver for GENI based QUP cores"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c new file mode 100644 index 000000000..598102d16 --- /dev/null +++ b/drivers/i2c/busses/i2c-qup.c @@ -0,0 +1,1991 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2009-2013, 2016-2018, The Linux Foundation. All rights reserved. + * Copyright (c) 2014, Sony Mobile Communications AB. + * + */ + +#include <linux/acpi.h> +#include <linux/atomic.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dmapool.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/scatterlist.h> + +/* QUP Registers */ +#define QUP_CONFIG 0x000 +#define QUP_STATE 0x004 +#define QUP_IO_MODE 0x008 +#define QUP_SW_RESET 0x00c +#define QUP_OPERATIONAL 0x018 +#define QUP_ERROR_FLAGS 0x01c +#define QUP_ERROR_FLAGS_EN 0x020 +#define QUP_OPERATIONAL_MASK 0x028 +#define QUP_HW_VERSION 0x030 +#define QUP_MX_OUTPUT_CNT 0x100 +#define QUP_OUT_FIFO_BASE 0x110 +#define QUP_MX_WRITE_CNT 0x150 +#define QUP_MX_INPUT_CNT 0x200 +#define QUP_MX_READ_CNT 0x208 +#define QUP_IN_FIFO_BASE 0x218 +#define QUP_I2C_CLK_CTL 0x400 +#define QUP_I2C_STATUS 0x404 +#define QUP_I2C_MASTER_GEN 0x408 + +/* QUP States and reset values */ +#define QUP_RESET_STATE 0 +#define QUP_RUN_STATE 1 +#define QUP_PAUSE_STATE 3 +#define QUP_STATE_MASK 3 + +#define QUP_STATE_VALID BIT(2) +#define QUP_I2C_MAST_GEN BIT(4) +#define QUP_I2C_FLUSH BIT(6) + +#define QUP_OPERATIONAL_RESET 0x000ff0 +#define QUP_I2C_STATUS_RESET 0xfffffc + +/* QUP OPERATIONAL FLAGS */ +#define QUP_I2C_NACK_FLAG BIT(3) +#define QUP_OUT_NOT_EMPTY BIT(4) +#define QUP_IN_NOT_EMPTY BIT(5) +#define QUP_OUT_FULL BIT(6) +#define QUP_OUT_SVC_FLAG BIT(8) +#define QUP_IN_SVC_FLAG BIT(9) +#define QUP_MX_OUTPUT_DONE BIT(10) +#define QUP_MX_INPUT_DONE BIT(11) +#define OUT_BLOCK_WRITE_REQ BIT(12) +#define IN_BLOCK_READ_REQ BIT(13) + +/* I2C mini core related values */ +#define QUP_NO_INPUT BIT(7) +#define QUP_CLOCK_AUTO_GATE BIT(13) +#define I2C_MINI_CORE (2 << 8) +#define I2C_N_VAL 15 +#define I2C_N_VAL_V2 7 + +/* Most significant word offset in FIFO port */ +#define QUP_MSW_SHIFT (I2C_N_VAL + 1) + +/* Packing/Unpacking words in FIFOs, and IO modes */ +#define QUP_OUTPUT_BLK_MODE (1 << 10) +#define QUP_OUTPUT_BAM_MODE (3 << 10) +#define QUP_INPUT_BLK_MODE (1 << 12) +#define QUP_INPUT_BAM_MODE (3 << 12) +#define QUP_BAM_MODE (QUP_OUTPUT_BAM_MODE | QUP_INPUT_BAM_MODE) +#define QUP_UNPACK_EN BIT(14) +#define QUP_PACK_EN BIT(15) + +#define QUP_REPACK_EN (QUP_UNPACK_EN | QUP_PACK_EN) +#define QUP_V2_TAGS_EN 1 + +#define QUP_OUTPUT_BLOCK_SIZE(x)(((x) >> 0) & 0x03) +#define QUP_OUTPUT_FIFO_SIZE(x) (((x) >> 2) & 0x07) +#define QUP_INPUT_BLOCK_SIZE(x) (((x) >> 5) & 0x03) +#define QUP_INPUT_FIFO_SIZE(x) (((x) >> 7) & 0x07) + +/* QUP tags */ +#define QUP_TAG_START (1 << 8) +#define QUP_TAG_DATA (2 << 8) +#define QUP_TAG_STOP (3 << 8) +#define QUP_TAG_REC (4 << 8) +#define QUP_BAM_INPUT_EOT 0x93 +#define QUP_BAM_FLUSH_STOP 0x96 + +/* QUP v2 tags */ +#define QUP_TAG_V2_START 0x81 +#define QUP_TAG_V2_DATAWR 0x82 +#define QUP_TAG_V2_DATAWR_STOP 0x83 +#define QUP_TAG_V2_DATARD 0x85 +#define QUP_TAG_V2_DATARD_NACK 0x86 +#define QUP_TAG_V2_DATARD_STOP 0x87 + +/* Status, Error flags */ +#define I2C_STATUS_WR_BUFFER_FULL BIT(0) +#define I2C_STATUS_BUS_ACTIVE BIT(8) +#define I2C_STATUS_ERROR_MASK 0x38000fc +#define QUP_STATUS_ERROR_FLAGS 0x7c + +#define QUP_READ_LIMIT 256 +#define SET_BIT 0x1 +#define RESET_BIT 0x0 +#define ONE_BYTE 0x1 +#define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31) + +/* Maximum transfer length for single DMA descriptor */ +#define MX_TX_RX_LEN SZ_64K +#define MX_BLOCKS (MX_TX_RX_LEN / QUP_READ_LIMIT) +/* Maximum transfer length for all DMA descriptors */ +#define MX_DMA_TX_RX_LEN (2 * MX_TX_RX_LEN) +#define MX_DMA_BLOCKS (MX_DMA_TX_RX_LEN / QUP_READ_LIMIT) + +/* + * Minimum transfer timeout for i2c transfers in seconds. It will be added on + * the top of maximum transfer time calculated from i2c bus speed to compensate + * the overheads. + */ +#define TOUT_MIN 2 + +/* Default values. Use these if FW query fails */ +#define DEFAULT_CLK_FREQ I2C_MAX_STANDARD_MODE_FREQ +#define DEFAULT_SRC_CLK 20000000 + +/* + * Max tags length (start, stop and maximum 2 bytes address) for each QUP + * data transfer + */ +#define QUP_MAX_TAGS_LEN 4 +/* Max data length for each DATARD tags */ +#define RECV_MAX_DATA_LEN 254 +/* TAG length for DATA READ in RX FIFO */ +#define READ_RX_TAGS_LEN 2 + +static unsigned int scl_freq; +module_param_named(scl_freq, scl_freq, uint, 0444); +MODULE_PARM_DESC(scl_freq, "SCL frequency override"); + +/* + * count: no of blocks + * pos: current block number + * tx_tag_len: tx tag length for current block + * rx_tag_len: rx tag length for current block + * data_len: remaining data length for current message + * cur_blk_len: data length for current block + * total_tx_len: total tx length including tag bytes for current QUP transfer + * total_rx_len: total rx length including tag bytes for current QUP transfer + * tx_fifo_data_pos: current byte number in TX FIFO word + * tx_fifo_free: number of free bytes in current QUP block write. + * rx_fifo_data_pos: current byte number in RX FIFO word + * fifo_available: number of available bytes in RX FIFO for current + * QUP block read + * tx_fifo_data: QUP TX FIFO write works on word basis (4 bytes). New byte write + * to TX FIFO will be appended in this data and will be written to + * TX FIFO when all the 4 bytes are available. + * rx_fifo_data: QUP RX FIFO read works on word basis (4 bytes). This will + * contains the 4 bytes of RX data. + * cur_data: pointer to tell cur data position for current message + * cur_tx_tags: pointer to tell cur position in tags + * tx_tags_sent: all tx tag bytes have been written in FIFO word + * send_last_word: for tx FIFO, last word send is pending in current block + * rx_bytes_read: if all the bytes have been read from rx FIFO. + * rx_tags_fetched: all the rx tag bytes have been fetched from rx fifo word + * is_tx_blk_mode: whether tx uses block or FIFO mode in case of non BAM xfer. + * is_rx_blk_mode: whether rx uses block or FIFO mode in case of non BAM xfer. + * tags: contains tx tag bytes for current QUP transfer + */ +struct qup_i2c_block { + int count; + int pos; + int tx_tag_len; + int rx_tag_len; + int data_len; + int cur_blk_len; + int total_tx_len; + int total_rx_len; + int tx_fifo_data_pos; + int tx_fifo_free; + int rx_fifo_data_pos; + int fifo_available; + u32 tx_fifo_data; + u32 rx_fifo_data; + u8 *cur_data; + u8 *cur_tx_tags; + bool tx_tags_sent; + bool send_last_word; + bool rx_tags_fetched; + bool rx_bytes_read; + bool is_tx_blk_mode; + bool is_rx_blk_mode; + u8 tags[6]; +}; + +struct qup_i2c_tag { + u8 *start; + dma_addr_t addr; +}; + +struct qup_i2c_bam { + struct qup_i2c_tag tag; + struct dma_chan *dma; + struct scatterlist *sg; + unsigned int sg_cnt; +}; + +struct qup_i2c_dev { + struct device *dev; + void __iomem *base; + int irq; + struct clk *clk; + struct clk *pclk; + struct i2c_adapter adap; + + int clk_ctl; + int out_fifo_sz; + int in_fifo_sz; + int out_blk_sz; + int in_blk_sz; + + int blk_xfer_limit; + unsigned long one_byte_t; + unsigned long xfer_timeout; + struct qup_i2c_block blk; + + struct i2c_msg *msg; + /* Current posion in user message buffer */ + int pos; + /* I2C protocol errors */ + u32 bus_err; + /* QUP core errors */ + u32 qup_err; + + /* To check if this is the last msg */ + bool is_last; + bool is_smbus_read; + + /* To configure when bus is in run state */ + u32 config_run; + + /* dma parameters */ + bool is_dma; + /* To check if the current transfer is using DMA */ + bool use_dma; + unsigned int max_xfer_sg_len; + unsigned int tag_buf_pos; + /* The threshold length above which block mode will be used */ + unsigned int blk_mode_threshold; + struct dma_pool *dpool; + struct qup_i2c_tag start_tag; + struct qup_i2c_bam brx; + struct qup_i2c_bam btx; + + struct completion xfer; + /* function to write data in tx fifo */ + void (*write_tx_fifo)(struct qup_i2c_dev *qup); + /* function to read data from rx fifo */ + void (*read_rx_fifo)(struct qup_i2c_dev *qup); + /* function to write tags in tx fifo for i2c read transfer */ + void (*write_rx_tags)(struct qup_i2c_dev *qup); +}; + +static irqreturn_t qup_i2c_interrupt(int irq, void *dev) +{ + struct qup_i2c_dev *qup = dev; + struct qup_i2c_block *blk = &qup->blk; + u32 bus_err; + u32 qup_err; + u32 opflags; + + bus_err = readl(qup->base + QUP_I2C_STATUS); + qup_err = readl(qup->base + QUP_ERROR_FLAGS); + opflags = readl(qup->base + QUP_OPERATIONAL); + + if (!qup->msg) { + /* Clear Error interrupt */ + writel(QUP_RESET_STATE, qup->base + QUP_STATE); + return IRQ_HANDLED; + } + + bus_err &= I2C_STATUS_ERROR_MASK; + qup_err &= QUP_STATUS_ERROR_FLAGS; + + /* Clear the error bits in QUP_ERROR_FLAGS */ + if (qup_err) + writel(qup_err, qup->base + QUP_ERROR_FLAGS); + + /* Clear the error bits in QUP_I2C_STATUS */ + if (bus_err) + writel(bus_err, qup->base + QUP_I2C_STATUS); + + /* + * Check for BAM mode and returns if already error has come for current + * transfer. In Error case, sometimes, QUP generates more than one + * interrupt. + */ + if (qup->use_dma && (qup->qup_err || qup->bus_err)) + return IRQ_HANDLED; + + /* Reset the QUP State in case of error */ + if (qup_err || bus_err) { + /* + * Don’t reset the QUP state in case of BAM mode. The BAM + * flush operation needs to be scheduled in transfer function + * which will clear the remaining schedule descriptors in BAM + * HW FIFO and generates the BAM interrupt. + */ + if (!qup->use_dma) + writel(QUP_RESET_STATE, qup->base + QUP_STATE); + goto done; + } + + if (opflags & QUP_OUT_SVC_FLAG) { + writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL); + + if (opflags & OUT_BLOCK_WRITE_REQ) { + blk->tx_fifo_free += qup->out_blk_sz; + if (qup->msg->flags & I2C_M_RD) + qup->write_rx_tags(qup); + else + qup->write_tx_fifo(qup); + } + } + + if (opflags & QUP_IN_SVC_FLAG) { + writel(QUP_IN_SVC_FLAG, qup->base + QUP_OPERATIONAL); + + if (!blk->is_rx_blk_mode) { + blk->fifo_available += qup->in_fifo_sz; + qup->read_rx_fifo(qup); + } else if (opflags & IN_BLOCK_READ_REQ) { + blk->fifo_available += qup->in_blk_sz; + qup->read_rx_fifo(qup); + } + } + + if (qup->msg->flags & I2C_M_RD) { + if (!blk->rx_bytes_read) + return IRQ_HANDLED; + } else { + /* + * Ideally, QUP_MAX_OUTPUT_DONE_FLAG should be checked + * for FIFO mode also. But, QUP_MAX_OUTPUT_DONE_FLAG lags + * behind QUP_OUTPUT_SERVICE_FLAG sometimes. The only reason + * of interrupt for write message in FIFO mode is + * QUP_MAX_OUTPUT_DONE_FLAG condition. + */ + if (blk->is_tx_blk_mode && !(opflags & QUP_MX_OUTPUT_DONE)) + return IRQ_HANDLED; + } + +done: + qup->qup_err = qup_err; + qup->bus_err = bus_err; + complete(&qup->xfer); + return IRQ_HANDLED; +} + +static int qup_i2c_poll_state_mask(struct qup_i2c_dev *qup, + u32 req_state, u32 req_mask) +{ + int retries = 1; + u32 state; + + /* + * State transition takes 3 AHB clocks cycles + 3 I2C master clock + * cycles. So retry once after a 1uS delay. + */ + do { + state = readl(qup->base + QUP_STATE); + + if (state & QUP_STATE_VALID && + (state & req_mask) == req_state) + return 0; + + udelay(1); + } while (retries--); + + return -ETIMEDOUT; +} + +static int qup_i2c_poll_state(struct qup_i2c_dev *qup, u32 req_state) +{ + return qup_i2c_poll_state_mask(qup, req_state, QUP_STATE_MASK); +} + +static void qup_i2c_flush(struct qup_i2c_dev *qup) +{ + u32 val = readl(qup->base + QUP_STATE); + + val |= QUP_I2C_FLUSH; + writel(val, qup->base + QUP_STATE); +} + +static int qup_i2c_poll_state_valid(struct qup_i2c_dev *qup) +{ + return qup_i2c_poll_state_mask(qup, 0, 0); +} + +static int qup_i2c_poll_state_i2c_master(struct qup_i2c_dev *qup) +{ + return qup_i2c_poll_state_mask(qup, QUP_I2C_MAST_GEN, QUP_I2C_MAST_GEN); +} + +static int qup_i2c_change_state(struct qup_i2c_dev *qup, u32 state) +{ + if (qup_i2c_poll_state_valid(qup) != 0) + return -EIO; + + writel(state, qup->base + QUP_STATE); + + if (qup_i2c_poll_state(qup, state) != 0) + return -EIO; + return 0; +} + +/* Check if I2C bus returns to IDLE state */ +static int qup_i2c_bus_active(struct qup_i2c_dev *qup, int len) +{ + unsigned long timeout; + u32 status; + int ret = 0; + + timeout = jiffies + len * 4; + for (;;) { + status = readl(qup->base + QUP_I2C_STATUS); + if (!(status & I2C_STATUS_BUS_ACTIVE)) + break; + + if (time_after(jiffies, timeout)) + ret = -ETIMEDOUT; + + usleep_range(len, len * 2); + } + + return ret; +} + +static void qup_i2c_write_tx_fifo_v1(struct qup_i2c_dev *qup) +{ + struct qup_i2c_block *blk = &qup->blk; + struct i2c_msg *msg = qup->msg; + u32 addr = i2c_8bit_addr_from_msg(msg); + u32 qup_tag; + int idx; + u32 val; + + if (qup->pos == 0) { + val = QUP_TAG_START | addr; + idx = 1; + blk->tx_fifo_free--; + } else { + val = 0; + idx = 0; + } + + while (blk->tx_fifo_free && qup->pos < msg->len) { + if (qup->pos == msg->len - 1) + qup_tag = QUP_TAG_STOP; + else + qup_tag = QUP_TAG_DATA; + + if (idx & 1) + val |= (qup_tag | msg->buf[qup->pos]) << QUP_MSW_SHIFT; + else + val = qup_tag | msg->buf[qup->pos]; + + /* Write out the pair and the last odd value */ + if (idx & 1 || qup->pos == msg->len - 1) + writel(val, qup->base + QUP_OUT_FIFO_BASE); + + qup->pos++; + idx++; + blk->tx_fifo_free--; + } +} + +static void qup_i2c_set_blk_data(struct qup_i2c_dev *qup, + struct i2c_msg *msg) +{ + qup->blk.pos = 0; + qup->blk.data_len = msg->len; + qup->blk.count = DIV_ROUND_UP(msg->len, qup->blk_xfer_limit); +} + +static int qup_i2c_get_data_len(struct qup_i2c_dev *qup) +{ + int data_len; + + if (qup->blk.data_len > qup->blk_xfer_limit) + data_len = qup->blk_xfer_limit; + else + data_len = qup->blk.data_len; + + return data_len; +} + +static bool qup_i2c_check_msg_len(struct i2c_msg *msg) +{ + return ((msg->flags & I2C_M_RD) && (msg->flags & I2C_M_RECV_LEN)); +} + +static int qup_i2c_set_tags_smb(u16 addr, u8 *tags, struct qup_i2c_dev *qup, + struct i2c_msg *msg) +{ + int len = 0; + + if (qup->is_smbus_read) { + tags[len++] = QUP_TAG_V2_DATARD_STOP; + tags[len++] = qup_i2c_get_data_len(qup); + } else { + tags[len++] = QUP_TAG_V2_START; + tags[len++] = addr & 0xff; + + if (msg->flags & I2C_M_TEN) + tags[len++] = addr >> 8; + + tags[len++] = QUP_TAG_V2_DATARD; + /* Read 1 byte indicating the length of the SMBus message */ + tags[len++] = 1; + } + return len; +} + +static int qup_i2c_set_tags(u8 *tags, struct qup_i2c_dev *qup, + struct i2c_msg *msg) +{ + u16 addr = i2c_8bit_addr_from_msg(msg); + int len = 0; + int data_len; + + int last = (qup->blk.pos == (qup->blk.count - 1)) && (qup->is_last); + + /* Handle tags for SMBus block read */ + if (qup_i2c_check_msg_len(msg)) + return qup_i2c_set_tags_smb(addr, tags, qup, msg); + + if (qup->blk.pos == 0) { + tags[len++] = QUP_TAG_V2_START; + tags[len++] = addr & 0xff; + + if (msg->flags & I2C_M_TEN) + tags[len++] = addr >> 8; + } + + /* Send _STOP commands for the last block */ + if (last) { + if (msg->flags & I2C_M_RD) + tags[len++] = QUP_TAG_V2_DATARD_STOP; + else + tags[len++] = QUP_TAG_V2_DATAWR_STOP; + } else { + if (msg->flags & I2C_M_RD) + tags[len++] = qup->blk.pos == (qup->blk.count - 1) ? + QUP_TAG_V2_DATARD_NACK : + QUP_TAG_V2_DATARD; + else + tags[len++] = QUP_TAG_V2_DATAWR; + } + + data_len = qup_i2c_get_data_len(qup); + + /* 0 implies 256 bytes */ + if (data_len == QUP_READ_LIMIT) + tags[len++] = 0; + else + tags[len++] = data_len; + + return len; +} + + +static void qup_i2c_bam_cb(void *data) +{ + struct qup_i2c_dev *qup = data; + + complete(&qup->xfer); +} + +static int qup_sg_set_buf(struct scatterlist *sg, void *buf, + unsigned int buflen, struct qup_i2c_dev *qup, + int dir) +{ + int ret; + + sg_set_buf(sg, buf, buflen); + ret = dma_map_sg(qup->dev, sg, 1, dir); + if (!ret) + return -EINVAL; + + return 0; +} + +static void qup_i2c_rel_dma(struct qup_i2c_dev *qup) +{ + if (qup->btx.dma) + dma_release_channel(qup->btx.dma); + if (qup->brx.dma) + dma_release_channel(qup->brx.dma); + qup->btx.dma = NULL; + qup->brx.dma = NULL; +} + +static int qup_i2c_req_dma(struct qup_i2c_dev *qup) +{ + int err; + + if (!qup->btx.dma) { + qup->btx.dma = dma_request_chan(qup->dev, "tx"); + if (IS_ERR(qup->btx.dma)) { + err = PTR_ERR(qup->btx.dma); + qup->btx.dma = NULL; + dev_err(qup->dev, "\n tx channel not available"); + return err; + } + } + + if (!qup->brx.dma) { + qup->brx.dma = dma_request_chan(qup->dev, "rx"); + if (IS_ERR(qup->brx.dma)) { + dev_err(qup->dev, "\n rx channel not available"); + err = PTR_ERR(qup->brx.dma); + qup->brx.dma = NULL; + qup_i2c_rel_dma(qup); + return err; + } + } + return 0; +} + +static int qup_i2c_bam_make_desc(struct qup_i2c_dev *qup, struct i2c_msg *msg) +{ + int ret = 0, limit = QUP_READ_LIMIT; + u32 len = 0, blocks, rem; + u32 i = 0, tlen, tx_len = 0; + u8 *tags; + + qup->blk_xfer_limit = QUP_READ_LIMIT; + qup_i2c_set_blk_data(qup, msg); + + blocks = qup->blk.count; + rem = msg->len - (blocks - 1) * limit; + + if (msg->flags & I2C_M_RD) { + while (qup->blk.pos < blocks) { + tlen = (i == (blocks - 1)) ? rem : limit; + tags = &qup->start_tag.start[qup->tag_buf_pos + len]; + len += qup_i2c_set_tags(tags, qup, msg); + qup->blk.data_len -= tlen; + + /* scratch buf to read the start and len tags */ + ret = qup_sg_set_buf(&qup->brx.sg[qup->brx.sg_cnt++], + &qup->brx.tag.start[0], + 2, qup, DMA_FROM_DEVICE); + + if (ret) + return ret; + + ret = qup_sg_set_buf(&qup->brx.sg[qup->brx.sg_cnt++], + &msg->buf[limit * i], + tlen, qup, + DMA_FROM_DEVICE); + if (ret) + return ret; + + i++; + qup->blk.pos = i; + } + ret = qup_sg_set_buf(&qup->btx.sg[qup->btx.sg_cnt++], + &qup->start_tag.start[qup->tag_buf_pos], + len, qup, DMA_TO_DEVICE); + if (ret) + return ret; + + qup->tag_buf_pos += len; + } else { + while (qup->blk.pos < blocks) { + tlen = (i == (blocks - 1)) ? rem : limit; + tags = &qup->start_tag.start[qup->tag_buf_pos + tx_len]; + len = qup_i2c_set_tags(tags, qup, msg); + qup->blk.data_len -= tlen; + + ret = qup_sg_set_buf(&qup->btx.sg[qup->btx.sg_cnt++], + tags, len, + qup, DMA_TO_DEVICE); + if (ret) + return ret; + + tx_len += len; + ret = qup_sg_set_buf(&qup->btx.sg[qup->btx.sg_cnt++], + &msg->buf[limit * i], + tlen, qup, DMA_TO_DEVICE); + if (ret) + return ret; + i++; + qup->blk.pos = i; + } + + qup->tag_buf_pos += tx_len; + } + + return 0; +} + +static int qup_i2c_bam_schedule_desc(struct qup_i2c_dev *qup) +{ + struct dma_async_tx_descriptor *txd, *rxd = NULL; + int ret = 0; + dma_cookie_t cookie_rx, cookie_tx; + u32 len = 0; + u32 tx_cnt = qup->btx.sg_cnt, rx_cnt = qup->brx.sg_cnt; + + /* schedule the EOT and FLUSH I2C tags */ + len = 1; + if (rx_cnt) { + qup->btx.tag.start[0] = QUP_BAM_INPUT_EOT; + len++; + + /* scratch buf to read the BAM EOT FLUSH tags */ + ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++], + &qup->brx.tag.start[0], + 1, qup, DMA_FROM_DEVICE); + if (ret) + return ret; + } + + qup->btx.tag.start[len - 1] = QUP_BAM_FLUSH_STOP; + ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++], &qup->btx.tag.start[0], + len, qup, DMA_TO_DEVICE); + if (ret) + return ret; + + txd = dmaengine_prep_slave_sg(qup->btx.dma, qup->btx.sg, tx_cnt, + DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_PREP_FENCE); + if (!txd) { + dev_err(qup->dev, "failed to get tx desc\n"); + ret = -EINVAL; + goto desc_err; + } + + if (!rx_cnt) { + txd->callback = qup_i2c_bam_cb; + txd->callback_param = qup; + } + + cookie_tx = dmaengine_submit(txd); + if (dma_submit_error(cookie_tx)) { + ret = -EINVAL; + goto desc_err; + } + + dma_async_issue_pending(qup->btx.dma); + + if (rx_cnt) { + rxd = dmaengine_prep_slave_sg(qup->brx.dma, qup->brx.sg, + rx_cnt, DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT); + if (!rxd) { + dev_err(qup->dev, "failed to get rx desc\n"); + ret = -EINVAL; + + /* abort TX descriptors */ + dmaengine_terminate_sync(qup->btx.dma); + goto desc_err; + } + + rxd->callback = qup_i2c_bam_cb; + rxd->callback_param = qup; + cookie_rx = dmaengine_submit(rxd); + if (dma_submit_error(cookie_rx)) { + ret = -EINVAL; + goto desc_err; + } + + dma_async_issue_pending(qup->brx.dma); + } + + if (!wait_for_completion_timeout(&qup->xfer, qup->xfer_timeout)) { + dev_err(qup->dev, "normal trans timed out\n"); + ret = -ETIMEDOUT; + } + + if (ret || qup->bus_err || qup->qup_err) { + reinit_completion(&qup->xfer); + + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); + if (ret) { + dev_err(qup->dev, "change to run state timed out"); + goto desc_err; + } + + qup_i2c_flush(qup); + + /* wait for remaining interrupts to occur */ + if (!wait_for_completion_timeout(&qup->xfer, HZ)) + dev_err(qup->dev, "flush timed out\n"); + + ret = (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO; + } + +desc_err: + dma_unmap_sg(qup->dev, qup->btx.sg, tx_cnt, DMA_TO_DEVICE); + + if (rx_cnt) + dma_unmap_sg(qup->dev, qup->brx.sg, rx_cnt, + DMA_FROM_DEVICE); + + return ret; +} + +static void qup_i2c_bam_clear_tag_buffers(struct qup_i2c_dev *qup) +{ + qup->btx.sg_cnt = 0; + qup->brx.sg_cnt = 0; + qup->tag_buf_pos = 0; +} + +static int qup_i2c_bam_xfer(struct i2c_adapter *adap, struct i2c_msg *msg, + int num) +{ + struct qup_i2c_dev *qup = i2c_get_adapdata(adap); + int ret = 0; + int idx = 0; + + enable_irq(qup->irq); + ret = qup_i2c_req_dma(qup); + + if (ret) + goto out; + + writel(0, qup->base + QUP_MX_INPUT_CNT); + writel(0, qup->base + QUP_MX_OUTPUT_CNT); + + /* set BAM mode */ + writel(QUP_REPACK_EN | QUP_BAM_MODE, qup->base + QUP_IO_MODE); + + /* mask fifo irqs */ + writel((0x3 << 8), qup->base + QUP_OPERATIONAL_MASK); + + /* set RUN STATE */ + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); + if (ret) + goto out; + + writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL); + qup_i2c_bam_clear_tag_buffers(qup); + + for (idx = 0; idx < num; idx++) { + qup->msg = msg + idx; + qup->is_last = idx == (num - 1); + + ret = qup_i2c_bam_make_desc(qup, qup->msg); + if (ret) + break; + + /* + * Make DMA descriptor and schedule the BAM transfer if its + * already crossed the maximum length. Since the memory for all + * tags buffers have been taken for 2 maximum possible + * transfers length so it will never cross the buffer actual + * length. + */ + if (qup->btx.sg_cnt > qup->max_xfer_sg_len || + qup->brx.sg_cnt > qup->max_xfer_sg_len || + qup->is_last) { + ret = qup_i2c_bam_schedule_desc(qup); + if (ret) + break; + + qup_i2c_bam_clear_tag_buffers(qup); + } + } + +out: + disable_irq(qup->irq); + + qup->msg = NULL; + return ret; +} + +static int qup_i2c_wait_for_complete(struct qup_i2c_dev *qup, + struct i2c_msg *msg) +{ + unsigned long left; + int ret = 0; + + left = wait_for_completion_timeout(&qup->xfer, qup->xfer_timeout); + if (!left) { + writel(1, qup->base + QUP_SW_RESET); + ret = -ETIMEDOUT; + } + + if (qup->bus_err || qup->qup_err) + ret = (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO; + + return ret; +} + +static void qup_i2c_read_rx_fifo_v1(struct qup_i2c_dev *qup) +{ + struct qup_i2c_block *blk = &qup->blk; + struct i2c_msg *msg = qup->msg; + u32 val = 0; + int idx = 0; + + while (blk->fifo_available && qup->pos < msg->len) { + if ((idx & 1) == 0) { + /* Reading 2 words at time */ + val = readl(qup->base + QUP_IN_FIFO_BASE); + msg->buf[qup->pos++] = val & 0xFF; + } else { + msg->buf[qup->pos++] = val >> QUP_MSW_SHIFT; + } + idx++; + blk->fifo_available--; + } + + if (qup->pos == msg->len) + blk->rx_bytes_read = true; +} + +static void qup_i2c_write_rx_tags_v1(struct qup_i2c_dev *qup) +{ + struct i2c_msg *msg = qup->msg; + u32 addr, len, val; + + addr = i2c_8bit_addr_from_msg(msg); + + /* 0 is used to specify a length 256 (QUP_READ_LIMIT) */ + len = (msg->len == QUP_READ_LIMIT) ? 0 : msg->len; + + val = ((QUP_TAG_REC | len) << QUP_MSW_SHIFT) | QUP_TAG_START | addr; + writel(val, qup->base + QUP_OUT_FIFO_BASE); +} + +static void qup_i2c_conf_v1(struct qup_i2c_dev *qup) +{ + struct qup_i2c_block *blk = &qup->blk; + u32 qup_config = I2C_MINI_CORE | I2C_N_VAL; + u32 io_mode = QUP_REPACK_EN; + + blk->is_tx_blk_mode = blk->total_tx_len > qup->out_fifo_sz; + blk->is_rx_blk_mode = blk->total_rx_len > qup->in_fifo_sz; + + if (blk->is_tx_blk_mode) { + io_mode |= QUP_OUTPUT_BLK_MODE; + writel(0, qup->base + QUP_MX_WRITE_CNT); + writel(blk->total_tx_len, qup->base + QUP_MX_OUTPUT_CNT); + } else { + writel(0, qup->base + QUP_MX_OUTPUT_CNT); + writel(blk->total_tx_len, qup->base + QUP_MX_WRITE_CNT); + } + + if (blk->total_rx_len) { + if (blk->is_rx_blk_mode) { + io_mode |= QUP_INPUT_BLK_MODE; + writel(0, qup->base + QUP_MX_READ_CNT); + writel(blk->total_rx_len, qup->base + QUP_MX_INPUT_CNT); + } else { + writel(0, qup->base + QUP_MX_INPUT_CNT); + writel(blk->total_rx_len, qup->base + QUP_MX_READ_CNT); + } + } else { + qup_config |= QUP_NO_INPUT; + } + + writel(qup_config, qup->base + QUP_CONFIG); + writel(io_mode, qup->base + QUP_IO_MODE); +} + +static void qup_i2c_clear_blk_v1(struct qup_i2c_block *blk) +{ + blk->tx_fifo_free = 0; + blk->fifo_available = 0; + blk->rx_bytes_read = false; +} + +static int qup_i2c_conf_xfer_v1(struct qup_i2c_dev *qup, bool is_rx) +{ + struct qup_i2c_block *blk = &qup->blk; + int ret; + + qup_i2c_clear_blk_v1(blk); + qup_i2c_conf_v1(qup); + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); + if (ret) + return ret; + + writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL); + + ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); + if (ret) + return ret; + + reinit_completion(&qup->xfer); + enable_irq(qup->irq); + if (!blk->is_tx_blk_mode) { + blk->tx_fifo_free = qup->out_fifo_sz; + + if (is_rx) + qup_i2c_write_rx_tags_v1(qup); + else + qup_i2c_write_tx_fifo_v1(qup); + } + + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); + if (ret) + goto err; + + ret = qup_i2c_wait_for_complete(qup, qup->msg); + if (ret) + goto err; + + ret = qup_i2c_bus_active(qup, ONE_BYTE); + +err: + disable_irq(qup->irq); + return ret; +} + +static int qup_i2c_write_one(struct qup_i2c_dev *qup) +{ + struct i2c_msg *msg = qup->msg; + struct qup_i2c_block *blk = &qup->blk; + + qup->pos = 0; + blk->total_tx_len = msg->len + 1; + blk->total_rx_len = 0; + + return qup_i2c_conf_xfer_v1(qup, false); +} + +static int qup_i2c_read_one(struct qup_i2c_dev *qup) +{ + struct qup_i2c_block *blk = &qup->blk; + + qup->pos = 0; + blk->total_tx_len = 2; + blk->total_rx_len = qup->msg->len; + + return qup_i2c_conf_xfer_v1(qup, true); +} + +static int qup_i2c_xfer(struct i2c_adapter *adap, + struct i2c_msg msgs[], + int num) +{ + struct qup_i2c_dev *qup = i2c_get_adapdata(adap); + int ret, idx; + + ret = pm_runtime_get_sync(qup->dev); + if (ret < 0) + goto out; + + qup->bus_err = 0; + qup->qup_err = 0; + + writel(1, qup->base + QUP_SW_RESET); + ret = qup_i2c_poll_state(qup, QUP_RESET_STATE); + if (ret) + goto out; + + /* Configure QUP as I2C mini core */ + writel(I2C_MINI_CORE | I2C_N_VAL, qup->base + QUP_CONFIG); + + for (idx = 0; idx < num; idx++) { + if (qup_i2c_poll_state_i2c_master(qup)) { + ret = -EIO; + goto out; + } + + if (qup_i2c_check_msg_len(&msgs[idx])) { + ret = -EINVAL; + goto out; + } + + qup->msg = &msgs[idx]; + if (msgs[idx].flags & I2C_M_RD) + ret = qup_i2c_read_one(qup); + else + ret = qup_i2c_write_one(qup); + + if (ret) + break; + + ret = qup_i2c_change_state(qup, QUP_RESET_STATE); + if (ret) + break; + } + + if (ret == 0) + ret = num; +out: + + pm_runtime_mark_last_busy(qup->dev); + pm_runtime_put_autosuspend(qup->dev); + + return ret; +} + +/* + * Configure registers related with reconfiguration during run and call it + * before each i2c sub transfer. + */ +static void qup_i2c_conf_count_v2(struct qup_i2c_dev *qup) +{ + struct qup_i2c_block *blk = &qup->blk; + u32 qup_config = I2C_MINI_CORE | I2C_N_VAL_V2; + + if (blk->is_tx_blk_mode) + writel(qup->config_run | blk->total_tx_len, + qup->base + QUP_MX_OUTPUT_CNT); + else + writel(qup->config_run | blk->total_tx_len, + qup->base + QUP_MX_WRITE_CNT); + + if (blk->total_rx_len) { + if (blk->is_rx_blk_mode) + writel(qup->config_run | blk->total_rx_len, + qup->base + QUP_MX_INPUT_CNT); + else + writel(qup->config_run | blk->total_rx_len, + qup->base + QUP_MX_READ_CNT); + } else { + qup_config |= QUP_NO_INPUT; + } + + writel(qup_config, qup->base + QUP_CONFIG); +} + +/* + * Configure registers related with transfer mode (FIFO/Block) + * before starting of i2c transfer. It will be called only once in + * QUP RESET state. + */ +static void qup_i2c_conf_mode_v2(struct qup_i2c_dev *qup) +{ + struct qup_i2c_block *blk = &qup->blk; + u32 io_mode = QUP_REPACK_EN; + + if (blk->is_tx_blk_mode) { + io_mode |= QUP_OUTPUT_BLK_MODE; + writel(0, qup->base + QUP_MX_WRITE_CNT); + } else { + writel(0, qup->base + QUP_MX_OUTPUT_CNT); + } + + if (blk->is_rx_blk_mode) { + io_mode |= QUP_INPUT_BLK_MODE; + writel(0, qup->base + QUP_MX_READ_CNT); + } else { + writel(0, qup->base + QUP_MX_INPUT_CNT); + } + + writel(io_mode, qup->base + QUP_IO_MODE); +} + +/* Clear required variables before starting of any QUP v2 sub transfer. */ +static void qup_i2c_clear_blk_v2(struct qup_i2c_block *blk) +{ + blk->send_last_word = false; + blk->tx_tags_sent = false; + blk->tx_fifo_data = 0; + blk->tx_fifo_data_pos = 0; + blk->tx_fifo_free = 0; + + blk->rx_tags_fetched = false; + blk->rx_bytes_read = false; + blk->rx_fifo_data = 0; + blk->rx_fifo_data_pos = 0; + blk->fifo_available = 0; +} + +/* Receive data from RX FIFO for read message in QUP v2 i2c transfer. */ +static void qup_i2c_recv_data(struct qup_i2c_dev *qup) +{ + struct qup_i2c_block *blk = &qup->blk; + int j; + + for (j = blk->rx_fifo_data_pos; + blk->cur_blk_len && blk->fifo_available; + blk->cur_blk_len--, blk->fifo_available--) { + if (j == 0) + blk->rx_fifo_data = readl(qup->base + QUP_IN_FIFO_BASE); + + *(blk->cur_data++) = blk->rx_fifo_data; + blk->rx_fifo_data >>= 8; + + if (j == 3) + j = 0; + else + j++; + } + + blk->rx_fifo_data_pos = j; +} + +/* Receive tags for read message in QUP v2 i2c transfer. */ +static void qup_i2c_recv_tags(struct qup_i2c_dev *qup) +{ + struct qup_i2c_block *blk = &qup->blk; + + blk->rx_fifo_data = readl(qup->base + QUP_IN_FIFO_BASE); + blk->rx_fifo_data >>= blk->rx_tag_len * 8; + blk->rx_fifo_data_pos = blk->rx_tag_len; + blk->fifo_available -= blk->rx_tag_len; +} + +/* + * Read the data and tags from RX FIFO. Since in read case, the tags will be + * preceded by received data bytes so + * 1. Check if rx_tags_fetched is false i.e. the start of QUP block so receive + * all tag bytes and discard that. + * 2. Read the data from RX FIFO. When all the data bytes have been read then + * set rx_bytes_read to true. + */ +static void qup_i2c_read_rx_fifo_v2(struct qup_i2c_dev *qup) +{ + struct qup_i2c_block *blk = &qup->blk; + + if (!blk->rx_tags_fetched) { + qup_i2c_recv_tags(qup); + blk->rx_tags_fetched = true; + } + + qup_i2c_recv_data(qup); + if (!blk->cur_blk_len) + blk->rx_bytes_read = true; +} + +/* + * Write bytes in TX FIFO for write message in QUP v2 i2c transfer. QUP TX FIFO + * write works on word basis (4 bytes). Append new data byte write for TX FIFO + * in tx_fifo_data and write to TX FIFO when all the 4 bytes are present. + */ +static void +qup_i2c_write_blk_data(struct qup_i2c_dev *qup, u8 **data, unsigned int *len) +{ + struct qup_i2c_block *blk = &qup->blk; + unsigned int j; + + for (j = blk->tx_fifo_data_pos; *len && blk->tx_fifo_free; + (*len)--, blk->tx_fifo_free--) { + blk->tx_fifo_data |= *(*data)++ << (j * 8); + if (j == 3) { + writel(blk->tx_fifo_data, + qup->base + QUP_OUT_FIFO_BASE); + blk->tx_fifo_data = 0x0; + j = 0; + } else { + j++; + } + } + + blk->tx_fifo_data_pos = j; +} + +/* Transfer tags for read message in QUP v2 i2c transfer. */ +static void qup_i2c_write_rx_tags_v2(struct qup_i2c_dev *qup) +{ + struct qup_i2c_block *blk = &qup->blk; + + qup_i2c_write_blk_data(qup, &blk->cur_tx_tags, &blk->tx_tag_len); + if (blk->tx_fifo_data_pos) + writel(blk->tx_fifo_data, qup->base + QUP_OUT_FIFO_BASE); +} + +/* + * Write the data and tags in TX FIFO. Since in write case, both tags and data + * need to be written and QUP write tags can have maximum 256 data length, so + * + * 1. Check if tx_tags_sent is false i.e. the start of QUP block so write the + * tags to TX FIFO and set tx_tags_sent to true. + * 2. Check if send_last_word is true. It will be set when last few data bytes + * (less than 4 bytes) are remaining to be written in FIFO because of no FIFO + * space. All this data bytes are available in tx_fifo_data so write this + * in FIFO. + * 3. Write the data to TX FIFO and check for cur_blk_len. If it is non zero + * then more data is pending otherwise following 3 cases can be possible + * a. if tx_fifo_data_pos is zero i.e. all the data bytes in this block + * have been written in TX FIFO so nothing else is required. + * b. tx_fifo_free is non zero i.e tx FIFO is free so copy the remaining data + * from tx_fifo_data to tx FIFO. Since, qup_i2c_write_blk_data do write + * in 4 bytes and FIFO space is in multiple of 4 bytes so tx_fifo_free + * will be always greater than or equal to 4 bytes. + * c. tx_fifo_free is zero. In this case, last few bytes (less than 4 + * bytes) are copied to tx_fifo_data but couldn't be sent because of + * FIFO full so make send_last_word true. + */ +static void qup_i2c_write_tx_fifo_v2(struct qup_i2c_dev *qup) +{ + struct qup_i2c_block *blk = &qup->blk; + + if (!blk->tx_tags_sent) { + qup_i2c_write_blk_data(qup, &blk->cur_tx_tags, + &blk->tx_tag_len); + blk->tx_tags_sent = true; + } + + if (blk->send_last_word) + goto send_last_word; + + qup_i2c_write_blk_data(qup, &blk->cur_data, &blk->cur_blk_len); + if (!blk->cur_blk_len) { + if (!blk->tx_fifo_data_pos) + return; + + if (blk->tx_fifo_free) + goto send_last_word; + + blk->send_last_word = true; + } + + return; + +send_last_word: + writel(blk->tx_fifo_data, qup->base + QUP_OUT_FIFO_BASE); +} + +/* + * Main transfer function which read or write i2c data. + * The QUP v2 supports reconfiguration during run in which multiple i2c sub + * transfers can be scheduled. + */ +static int +qup_i2c_conf_xfer_v2(struct qup_i2c_dev *qup, bool is_rx, bool is_first, + bool change_pause_state) +{ + struct qup_i2c_block *blk = &qup->blk; + struct i2c_msg *msg = qup->msg; + int ret; + + /* + * Check if its SMBus Block read for which the top level read will be + * done into 2 QUP reads. One with message length 1 while other one is + * with actual length. + */ + if (qup_i2c_check_msg_len(msg)) { + if (qup->is_smbus_read) { + /* + * If the message length is already read in + * the first byte of the buffer, account for + * that by setting the offset + */ + blk->cur_data += 1; + is_first = false; + } else { + change_pause_state = false; + } + } + + qup->config_run = is_first ? 0 : QUP_I2C_MX_CONFIG_DURING_RUN; + + qup_i2c_clear_blk_v2(blk); + qup_i2c_conf_count_v2(qup); + + /* If it is first sub transfer, then configure i2c bus clocks */ + if (is_first) { + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); + if (ret) + return ret; + + writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL); + + ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); + if (ret) + return ret; + } + + reinit_completion(&qup->xfer); + enable_irq(qup->irq); + /* + * In FIFO mode, tx FIFO can be written directly while in block mode the + * it will be written after getting OUT_BLOCK_WRITE_REQ interrupt + */ + if (!blk->is_tx_blk_mode) { + blk->tx_fifo_free = qup->out_fifo_sz; + + if (is_rx) + qup_i2c_write_rx_tags_v2(qup); + else + qup_i2c_write_tx_fifo_v2(qup); + } + + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); + if (ret) + goto err; + + ret = qup_i2c_wait_for_complete(qup, msg); + if (ret) + goto err; + + /* Move to pause state for all the transfers, except last one */ + if (change_pause_state) { + ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); + if (ret) + goto err; + } + +err: + disable_irq(qup->irq); + return ret; +} + +/* + * Transfer one read/write message in i2c transfer. It splits the message into + * multiple of blk_xfer_limit data length blocks and schedule each + * QUP block individually. + */ +static int qup_i2c_xfer_v2_msg(struct qup_i2c_dev *qup, int msg_id, bool is_rx) +{ + int ret = 0; + unsigned int data_len, i; + struct i2c_msg *msg = qup->msg; + struct qup_i2c_block *blk = &qup->blk; + u8 *msg_buf = msg->buf; + + qup->blk_xfer_limit = is_rx ? RECV_MAX_DATA_LEN : QUP_READ_LIMIT; + qup_i2c_set_blk_data(qup, msg); + + for (i = 0; i < blk->count; i++) { + data_len = qup_i2c_get_data_len(qup); + blk->pos = i; + blk->cur_tx_tags = blk->tags; + blk->cur_blk_len = data_len; + blk->tx_tag_len = + qup_i2c_set_tags(blk->cur_tx_tags, qup, qup->msg); + + blk->cur_data = msg_buf; + + if (is_rx) { + blk->total_tx_len = blk->tx_tag_len; + blk->rx_tag_len = 2; + blk->total_rx_len = blk->rx_tag_len + data_len; + } else { + blk->total_tx_len = blk->tx_tag_len + data_len; + blk->total_rx_len = 0; + } + + ret = qup_i2c_conf_xfer_v2(qup, is_rx, !msg_id && !i, + !qup->is_last || i < blk->count - 1); + if (ret) + return ret; + + /* Handle SMBus block read length */ + if (qup_i2c_check_msg_len(msg) && msg->len == 1 && + !qup->is_smbus_read) { + if (msg->buf[0] > I2C_SMBUS_BLOCK_MAX) + return -EPROTO; + + msg->len = msg->buf[0]; + qup->is_smbus_read = true; + ret = qup_i2c_xfer_v2_msg(qup, msg_id, true); + qup->is_smbus_read = false; + if (ret) + return ret; + + msg->len += 1; + } + + msg_buf += data_len; + blk->data_len -= qup->blk_xfer_limit; + } + + return ret; +} + +/* + * QUP v2 supports 3 modes + * Programmed IO using FIFO mode : Less than FIFO size + * Programmed IO using Block mode : Greater than FIFO size + * DMA using BAM : Appropriate for any transaction size but the address should + * be DMA applicable + * + * This function determines the mode which will be used for this transfer. An + * i2c transfer contains multiple message. Following are the rules to determine + * the mode used. + * 1. Determine complete length, maximum tx and rx length for complete transfer. + * 2. If complete transfer length is greater than fifo size then use the DMA + * mode. + * 3. In FIFO or block mode, tx and rx can operate in different mode so check + * for maximum tx and rx length to determine mode. + */ +static int +qup_i2c_determine_mode_v2(struct qup_i2c_dev *qup, + struct i2c_msg msgs[], int num) +{ + int idx; + bool no_dma = false; + unsigned int max_tx_len = 0, max_rx_len = 0, total_len = 0; + + /* All i2c_msgs should be transferred using either dma or cpu */ + for (idx = 0; idx < num; idx++) { + if (msgs[idx].flags & I2C_M_RD) + max_rx_len = max_t(unsigned int, max_rx_len, + msgs[idx].len); + else + max_tx_len = max_t(unsigned int, max_tx_len, + msgs[idx].len); + + if (is_vmalloc_addr(msgs[idx].buf)) + no_dma = true; + + total_len += msgs[idx].len; + } + + if (!no_dma && qup->is_dma && + (total_len > qup->out_fifo_sz || total_len > qup->in_fifo_sz)) { + qup->use_dma = true; + } else { + qup->blk.is_tx_blk_mode = max_tx_len > qup->out_fifo_sz - + QUP_MAX_TAGS_LEN; + qup->blk.is_rx_blk_mode = max_rx_len > qup->in_fifo_sz - + READ_RX_TAGS_LEN; + } + + return 0; +} + +static int qup_i2c_xfer_v2(struct i2c_adapter *adap, + struct i2c_msg msgs[], + int num) +{ + struct qup_i2c_dev *qup = i2c_get_adapdata(adap); + int ret, idx = 0; + + qup->bus_err = 0; + qup->qup_err = 0; + + ret = pm_runtime_get_sync(qup->dev); + if (ret < 0) + goto out; + + ret = qup_i2c_determine_mode_v2(qup, msgs, num); + if (ret) + goto out; + + writel(1, qup->base + QUP_SW_RESET); + ret = qup_i2c_poll_state(qup, QUP_RESET_STATE); + if (ret) + goto out; + + /* Configure QUP as I2C mini core */ + writel(I2C_MINI_CORE | I2C_N_VAL_V2, qup->base + QUP_CONFIG); + writel(QUP_V2_TAGS_EN, qup->base + QUP_I2C_MASTER_GEN); + + if (qup_i2c_poll_state_i2c_master(qup)) { + ret = -EIO; + goto out; + } + + if (qup->use_dma) { + reinit_completion(&qup->xfer); + ret = qup_i2c_bam_xfer(adap, &msgs[0], num); + qup->use_dma = false; + } else { + qup_i2c_conf_mode_v2(qup); + + for (idx = 0; idx < num; idx++) { + qup->msg = &msgs[idx]; + qup->is_last = idx == (num - 1); + + ret = qup_i2c_xfer_v2_msg(qup, idx, + !!(msgs[idx].flags & I2C_M_RD)); + if (ret) + break; + } + qup->msg = NULL; + } + + if (!ret) + ret = qup_i2c_bus_active(qup, ONE_BYTE); + + if (!ret) + qup_i2c_change_state(qup, QUP_RESET_STATE); + + if (ret == 0) + ret = num; +out: + pm_runtime_mark_last_busy(qup->dev); + pm_runtime_put_autosuspend(qup->dev); + + return ret; +} + +static u32 qup_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL_ALL & ~I2C_FUNC_SMBUS_QUICK); +} + +static const struct i2c_algorithm qup_i2c_algo = { + .master_xfer = qup_i2c_xfer, + .functionality = qup_i2c_func, +}; + +static const struct i2c_algorithm qup_i2c_algo_v2 = { + .master_xfer = qup_i2c_xfer_v2, + .functionality = qup_i2c_func, +}; + +/* + * The QUP block will issue a NACK and STOP on the bus when reaching + * the end of the read, the length of the read is specified as one byte + * which limits the possible read to 256 (QUP_READ_LIMIT) bytes. + */ +static const struct i2c_adapter_quirks qup_i2c_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN, + .max_read_len = QUP_READ_LIMIT, +}; + +static const struct i2c_adapter_quirks qup_i2c_quirks_v2 = { + .flags = I2C_AQ_NO_ZERO_LEN, +}; + +static void qup_i2c_enable_clocks(struct qup_i2c_dev *qup) +{ + clk_prepare_enable(qup->clk); + clk_prepare_enable(qup->pclk); +} + +static void qup_i2c_disable_clocks(struct qup_i2c_dev *qup) +{ + u32 config; + + qup_i2c_change_state(qup, QUP_RESET_STATE); + clk_disable_unprepare(qup->clk); + config = readl(qup->base + QUP_CONFIG); + config |= QUP_CLOCK_AUTO_GATE; + writel(config, qup->base + QUP_CONFIG); + clk_disable_unprepare(qup->pclk); +} + +static const struct acpi_device_id qup_i2c_acpi_match[] = { + { "QCOM8010"}, + { }, +}; +MODULE_DEVICE_TABLE(acpi, qup_i2c_acpi_match); + +static int qup_i2c_probe(struct platform_device *pdev) +{ + static const int blk_sizes[] = {4, 16, 32}; + struct qup_i2c_dev *qup; + unsigned long one_bit_t; + u32 io_mode, hw_ver, size; + int ret, fs_div, hs_div; + u32 src_clk_freq = DEFAULT_SRC_CLK; + u32 clk_freq = DEFAULT_CLK_FREQ; + int blocks; + bool is_qup_v1; + + qup = devm_kzalloc(&pdev->dev, sizeof(*qup), GFP_KERNEL); + if (!qup) + return -ENOMEM; + + qup->dev = &pdev->dev; + init_completion(&qup->xfer); + platform_set_drvdata(pdev, qup); + + if (scl_freq) { + dev_notice(qup->dev, "Using override frequency of %u\n", scl_freq); + clk_freq = scl_freq; + } else { + ret = device_property_read_u32(qup->dev, "clock-frequency", &clk_freq); + if (ret) { + dev_notice(qup->dev, "using default clock-frequency %d", + DEFAULT_CLK_FREQ); + } + } + + if (of_device_is_compatible(pdev->dev.of_node, "qcom,i2c-qup-v1.1.1")) { + qup->adap.algo = &qup_i2c_algo; + qup->adap.quirks = &qup_i2c_quirks; + is_qup_v1 = true; + } else { + qup->adap.algo = &qup_i2c_algo_v2; + qup->adap.quirks = &qup_i2c_quirks_v2; + is_qup_v1 = false; + if (acpi_match_device(qup_i2c_acpi_match, qup->dev)) + goto nodma; + else + ret = qup_i2c_req_dma(qup); + + if (ret == -EPROBE_DEFER) + goto fail_dma; + else if (ret != 0) + goto nodma; + + qup->max_xfer_sg_len = (MX_BLOCKS << 1); + blocks = (MX_DMA_BLOCKS << 1) + 1; + qup->btx.sg = devm_kcalloc(&pdev->dev, + blocks, sizeof(*qup->btx.sg), + GFP_KERNEL); + if (!qup->btx.sg) { + ret = -ENOMEM; + goto fail_dma; + } + sg_init_table(qup->btx.sg, blocks); + + qup->brx.sg = devm_kcalloc(&pdev->dev, + blocks, sizeof(*qup->brx.sg), + GFP_KERNEL); + if (!qup->brx.sg) { + ret = -ENOMEM; + goto fail_dma; + } + sg_init_table(qup->brx.sg, blocks); + + /* 2 tag bytes for each block + 5 for start, stop tags */ + size = blocks * 2 + 5; + + qup->start_tag.start = devm_kzalloc(&pdev->dev, + size, GFP_KERNEL); + if (!qup->start_tag.start) { + ret = -ENOMEM; + goto fail_dma; + } + + qup->brx.tag.start = devm_kzalloc(&pdev->dev, 2, GFP_KERNEL); + if (!qup->brx.tag.start) { + ret = -ENOMEM; + goto fail_dma; + } + + qup->btx.tag.start = devm_kzalloc(&pdev->dev, 2, GFP_KERNEL); + if (!qup->btx.tag.start) { + ret = -ENOMEM; + goto fail_dma; + } + qup->is_dma = true; + } + +nodma: + /* We support frequencies up to FAST Mode Plus (1MHz) */ + if (!clk_freq || clk_freq > I2C_MAX_FAST_MODE_PLUS_FREQ) { + dev_err(qup->dev, "clock frequency not supported %d\n", + clk_freq); + ret = -EINVAL; + goto fail_dma; + } + + qup->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(qup->base)) { + ret = PTR_ERR(qup->base); + goto fail_dma; + } + + qup->irq = platform_get_irq(pdev, 0); + if (qup->irq < 0) { + ret = qup->irq; + goto fail_dma; + } + + if (has_acpi_companion(qup->dev)) { + ret = device_property_read_u32(qup->dev, + "src-clock-hz", &src_clk_freq); + if (ret) { + dev_notice(qup->dev, "using default src-clock-hz %d", + DEFAULT_SRC_CLK); + } + ACPI_COMPANION_SET(&qup->adap.dev, ACPI_COMPANION(qup->dev)); + } else { + qup->clk = devm_clk_get(qup->dev, "core"); + if (IS_ERR(qup->clk)) { + dev_err(qup->dev, "Could not get core clock\n"); + ret = PTR_ERR(qup->clk); + goto fail_dma; + } + + qup->pclk = devm_clk_get(qup->dev, "iface"); + if (IS_ERR(qup->pclk)) { + dev_err(qup->dev, "Could not get iface clock\n"); + ret = PTR_ERR(qup->pclk); + goto fail_dma; + } + qup_i2c_enable_clocks(qup); + src_clk_freq = clk_get_rate(qup->clk); + } + + /* + * Bootloaders might leave a pending interrupt on certain QUP's, + * so we reset the core before registering for interrupts. + */ + writel(1, qup->base + QUP_SW_RESET); + ret = qup_i2c_poll_state_valid(qup); + if (ret) + goto fail; + + ret = devm_request_irq(qup->dev, qup->irq, qup_i2c_interrupt, + IRQF_TRIGGER_HIGH | IRQF_NO_AUTOEN, + "i2c_qup", qup); + if (ret) { + dev_err(qup->dev, "Request %d IRQ failed\n", qup->irq); + goto fail; + } + + hw_ver = readl(qup->base + QUP_HW_VERSION); + dev_dbg(qup->dev, "Revision %x\n", hw_ver); + + io_mode = readl(qup->base + QUP_IO_MODE); + + /* + * The block/fifo size w.r.t. 'actual data' is 1/2 due to 'tag' + * associated with each byte written/received + */ + size = QUP_OUTPUT_BLOCK_SIZE(io_mode); + if (size >= ARRAY_SIZE(blk_sizes)) { + ret = -EIO; + goto fail; + } + qup->out_blk_sz = blk_sizes[size]; + + size = QUP_INPUT_BLOCK_SIZE(io_mode); + if (size >= ARRAY_SIZE(blk_sizes)) { + ret = -EIO; + goto fail; + } + qup->in_blk_sz = blk_sizes[size]; + + if (is_qup_v1) { + /* + * in QUP v1, QUP_CONFIG uses N as 15 i.e 16 bits constitutes a + * single transfer but the block size is in bytes so divide the + * in_blk_sz and out_blk_sz by 2 + */ + qup->in_blk_sz /= 2; + qup->out_blk_sz /= 2; + qup->write_tx_fifo = qup_i2c_write_tx_fifo_v1; + qup->read_rx_fifo = qup_i2c_read_rx_fifo_v1; + qup->write_rx_tags = qup_i2c_write_rx_tags_v1; + } else { + qup->write_tx_fifo = qup_i2c_write_tx_fifo_v2; + qup->read_rx_fifo = qup_i2c_read_rx_fifo_v2; + qup->write_rx_tags = qup_i2c_write_rx_tags_v2; + } + + size = QUP_OUTPUT_FIFO_SIZE(io_mode); + qup->out_fifo_sz = qup->out_blk_sz * (2 << size); + + size = QUP_INPUT_FIFO_SIZE(io_mode); + qup->in_fifo_sz = qup->in_blk_sz * (2 << size); + + hs_div = 3; + if (clk_freq <= I2C_MAX_STANDARD_MODE_FREQ) { + fs_div = ((src_clk_freq / clk_freq) / 2) - 3; + qup->clk_ctl = (hs_div << 8) | (fs_div & 0xff); + } else { + /* 33%/66% duty cycle */ + fs_div = ((src_clk_freq / clk_freq) - 6) * 2 / 3; + qup->clk_ctl = ((fs_div / 2) << 16) | (hs_div << 8) | (fs_div & 0xff); + } + + /* + * Time it takes for a byte to be clocked out on the bus. + * Each byte takes 9 clock cycles (8 bits + 1 ack). + */ + one_bit_t = (USEC_PER_SEC / clk_freq) + 1; + qup->one_byte_t = one_bit_t * 9; + qup->xfer_timeout = TOUT_MIN * HZ + + usecs_to_jiffies(MX_DMA_TX_RX_LEN * qup->one_byte_t); + + dev_dbg(qup->dev, "IN:block:%d, fifo:%d, OUT:block:%d, fifo:%d\n", + qup->in_blk_sz, qup->in_fifo_sz, + qup->out_blk_sz, qup->out_fifo_sz); + + i2c_set_adapdata(&qup->adap, qup); + qup->adap.dev.parent = qup->dev; + qup->adap.dev.of_node = pdev->dev.of_node; + qup->is_last = true; + + strscpy(qup->adap.name, "QUP I2C adapter", sizeof(qup->adap.name)); + + pm_runtime_set_autosuspend_delay(qup->dev, MSEC_PER_SEC); + pm_runtime_use_autosuspend(qup->dev); + pm_runtime_set_active(qup->dev); + pm_runtime_enable(qup->dev); + + ret = i2c_add_adapter(&qup->adap); + if (ret) + goto fail_runtime; + + return 0; + +fail_runtime: + pm_runtime_disable(qup->dev); + pm_runtime_set_suspended(qup->dev); +fail: + qup_i2c_disable_clocks(qup); +fail_dma: + if (qup->btx.dma) + dma_release_channel(qup->btx.dma); + if (qup->brx.dma) + dma_release_channel(qup->brx.dma); + return ret; +} + +static void qup_i2c_remove(struct platform_device *pdev) +{ + struct qup_i2c_dev *qup = platform_get_drvdata(pdev); + + if (qup->is_dma) { + dma_release_channel(qup->btx.dma); + dma_release_channel(qup->brx.dma); + } + + disable_irq(qup->irq); + qup_i2c_disable_clocks(qup); + i2c_del_adapter(&qup->adap); + pm_runtime_disable(qup->dev); + pm_runtime_set_suspended(qup->dev); +} + +static int qup_i2c_pm_suspend_runtime(struct device *device) +{ + struct qup_i2c_dev *qup = dev_get_drvdata(device); + + dev_dbg(device, "pm_runtime: suspending...\n"); + qup_i2c_disable_clocks(qup); + return 0; +} + +static int qup_i2c_pm_resume_runtime(struct device *device) +{ + struct qup_i2c_dev *qup = dev_get_drvdata(device); + + dev_dbg(device, "pm_runtime: resuming...\n"); + qup_i2c_enable_clocks(qup); + return 0; +} + +static int qup_i2c_suspend(struct device *device) +{ + if (!pm_runtime_suspended(device)) + return qup_i2c_pm_suspend_runtime(device); + return 0; +} + +static int qup_i2c_resume(struct device *device) +{ + qup_i2c_pm_resume_runtime(device); + pm_runtime_mark_last_busy(device); + pm_request_autosuspend(device); + return 0; +} + +static const struct dev_pm_ops qup_i2c_qup_pm_ops = { + SYSTEM_SLEEP_PM_OPS(qup_i2c_suspend, qup_i2c_resume) + RUNTIME_PM_OPS(qup_i2c_pm_suspend_runtime, + qup_i2c_pm_resume_runtime, NULL) +}; + +static const struct of_device_id qup_i2c_dt_match[] = { + { .compatible = "qcom,i2c-qup-v1.1.1" }, + { .compatible = "qcom,i2c-qup-v2.1.1" }, + { .compatible = "qcom,i2c-qup-v2.2.1" }, + {} +}; +MODULE_DEVICE_TABLE(of, qup_i2c_dt_match); + +static struct platform_driver qup_i2c_driver = { + .probe = qup_i2c_probe, + .remove_new = qup_i2c_remove, + .driver = { + .name = "i2c_qup", + .pm = pm_ptr(&qup_i2c_qup_pm_ops), + .of_match_table = qup_i2c_dt_match, + .acpi_match_table = ACPI_PTR(qup_i2c_acpi_match), + }, +}; + +module_platform_driver(qup_i2c_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:i2c_qup"); diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c new file mode 100644 index 000000000..a32a93f9a --- /dev/null +++ b/drivers/i2c/busses/i2c-rcar.c @@ -0,0 +1,1206 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for the Renesas R-Car I2C unit + * + * Copyright (C) 2014-19 Wolfram Sang <wsa@sang-engineering.com> + * Copyright (C) 2011-2019 Renesas Electronics Corporation + * + * Copyright (C) 2012-14 Renesas Solutions Corp. + * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> + * + * This file is based on the drivers/i2c/busses/i2c-sh7760.c + * (c) 2005-2008 MSC Vertriebsges.m.b.H, Manuel Lauss <mlau@msc-ge.com> + */ +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/i2c.h> +#include <linux/i2c-smbus.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/reset.h> +#include <linux/slab.h> + +/* register offsets */ +#define ICSCR 0x00 /* slave ctrl */ +#define ICMCR 0x04 /* master ctrl */ +#define ICSSR 0x08 /* slave status */ +#define ICMSR 0x0C /* master status */ +#define ICSIER 0x10 /* slave irq enable */ +#define ICMIER 0x14 /* master irq enable */ +#define ICCCR 0x18 /* clock dividers */ +#define ICSAR 0x1C /* slave address */ +#define ICMAR 0x20 /* master address */ +#define ICRXTX 0x24 /* data port */ +#define ICFBSCR 0x38 /* first bit setup cycle (Gen3) */ +#define ICDMAER 0x3c /* DMA enable (Gen3) */ + +/* ICSCR */ +#define SDBS BIT(3) /* slave data buffer select */ +#define SIE BIT(2) /* slave interface enable */ +#define GCAE BIT(1) /* general call address enable */ +#define FNA BIT(0) /* forced non acknowledgment */ + +/* ICMCR */ +#define MDBS BIT(7) /* non-fifo mode switch */ +#define FSCL BIT(6) /* override SCL pin */ +#define FSDA BIT(5) /* override SDA pin */ +#define OBPC BIT(4) /* override pins */ +#define MIE BIT(3) /* master if enable */ +#define TSBE BIT(2) +#define FSB BIT(1) /* force stop bit */ +#define ESG BIT(0) /* enable start bit gen */ + +/* ICSSR (also for ICSIER) */ +#define GCAR BIT(6) /* general call received */ +#define STM BIT(5) /* slave transmit mode */ +#define SSR BIT(4) /* stop received */ +#define SDE BIT(3) /* slave data empty */ +#define SDT BIT(2) /* slave data transmitted */ +#define SDR BIT(1) /* slave data received */ +#define SAR BIT(0) /* slave addr received */ + +/* ICMSR (also for ICMIE) */ +#define MNR BIT(6) /* nack received */ +#define MAL BIT(5) /* arbitration lost */ +#define MST BIT(4) /* sent a stop */ +#define MDE BIT(3) +#define MDT BIT(2) +#define MDR BIT(1) +#define MAT BIT(0) /* slave addr xfer done */ + +/* ICDMAER */ +#define RSDMAE BIT(3) /* DMA Slave Received Enable */ +#define TSDMAE BIT(2) /* DMA Slave Transmitted Enable */ +#define RMDMAE BIT(1) /* DMA Master Received Enable */ +#define TMDMAE BIT(0) /* DMA Master Transmitted Enable */ + +/* ICFBSCR */ +#define TCYC17 0x0f /* 17*Tcyc delay 1st bit between SDA and SCL */ + +#define RCAR_MIN_DMA_LEN 8 + +#define RCAR_BUS_PHASE_START (MDBS | MIE | ESG) +#define RCAR_BUS_PHASE_DATA (MDBS | MIE) +#define RCAR_BUS_PHASE_STOP (MDBS | MIE | FSB) + +#define RCAR_IRQ_SEND (MNR | MAL | MST | MAT | MDE) +#define RCAR_IRQ_RECV (MNR | MAL | MST | MAT | MDR) +#define RCAR_IRQ_STOP (MST) + +#define ID_LAST_MSG BIT(0) +#define ID_REP_AFTER_RD BIT(1) +#define ID_DONE BIT(2) +#define ID_ARBLOST BIT(3) +#define ID_NACK BIT(4) +#define ID_EPROTO BIT(5) +/* persistent flags */ +#define ID_P_NOT_ATOMIC BIT(28) +#define ID_P_HOST_NOTIFY BIT(29) +#define ID_P_NO_RXDMA BIT(30) /* HW forbids RXDMA sometimes */ +#define ID_P_PM_BLOCKED BIT(31) +#define ID_P_MASK GENMASK(31, 28) + +enum rcar_i2c_type { + I2C_RCAR_GEN1, + I2C_RCAR_GEN2, + I2C_RCAR_GEN3, +}; + +struct rcar_i2c_priv { + u32 flags; + void __iomem *io; + struct i2c_adapter adap; + struct i2c_msg *msg; + int msgs_left; + struct clk *clk; + + wait_queue_head_t wait; + + int pos; + u32 icccr; + u8 recovery_icmcr; /* protected by adapter lock */ + enum rcar_i2c_type devtype; + struct i2c_client *slave; + + struct resource *res; + struct dma_chan *dma_tx; + struct dma_chan *dma_rx; + struct scatterlist sg; + enum dma_data_direction dma_direction; + + struct reset_control *rstc; + int irq; + + struct i2c_client *host_notify_client; +}; + +#define rcar_i2c_priv_to_dev(p) ((p)->adap.dev.parent) +#define rcar_i2c_is_recv(p) ((p)->msg->flags & I2C_M_RD) + +static void rcar_i2c_write(struct rcar_i2c_priv *priv, int reg, u32 val) +{ + writel(val, priv->io + reg); +} + +static u32 rcar_i2c_read(struct rcar_i2c_priv *priv, int reg) +{ + return readl(priv->io + reg); +} + +static void rcar_i2c_clear_irq(struct rcar_i2c_priv *priv, u32 val) +{ + writel(~val & 0x7f, priv->io + ICMSR); +} + +static int rcar_i2c_get_scl(struct i2c_adapter *adap) +{ + struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); + + return !!(rcar_i2c_read(priv, ICMCR) & FSCL); + +}; + +static void rcar_i2c_set_scl(struct i2c_adapter *adap, int val) +{ + struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); + + if (val) + priv->recovery_icmcr |= FSCL; + else + priv->recovery_icmcr &= ~FSCL; + + rcar_i2c_write(priv, ICMCR, priv->recovery_icmcr); +}; + +static void rcar_i2c_set_sda(struct i2c_adapter *adap, int val) +{ + struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); + + if (val) + priv->recovery_icmcr |= FSDA; + else + priv->recovery_icmcr &= ~FSDA; + + rcar_i2c_write(priv, ICMCR, priv->recovery_icmcr); +}; + +static int rcar_i2c_get_bus_free(struct i2c_adapter *adap) +{ + struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); + + return !(rcar_i2c_read(priv, ICMCR) & FSDA); + +}; + +static struct i2c_bus_recovery_info rcar_i2c_bri = { + .get_scl = rcar_i2c_get_scl, + .set_scl = rcar_i2c_set_scl, + .set_sda = rcar_i2c_set_sda, + .get_bus_free = rcar_i2c_get_bus_free, + .recover_bus = i2c_generic_scl_recovery, +}; +static void rcar_i2c_init(struct rcar_i2c_priv *priv) +{ + /* reset master mode */ + rcar_i2c_write(priv, ICMIER, 0); + rcar_i2c_write(priv, ICMCR, MDBS); + rcar_i2c_write(priv, ICMSR, 0); + /* start clock */ + rcar_i2c_write(priv, ICCCR, priv->icccr); + + if (priv->devtype == I2C_RCAR_GEN3) + rcar_i2c_write(priv, ICFBSCR, TCYC17); + +} + +static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv) +{ + int ret; + u32 val; + + ret = readl_poll_timeout(priv->io + ICMCR, val, !(val & FSDA), 10, + priv->adap.timeout); + if (ret) { + /* Waiting did not help, try to recover */ + priv->recovery_icmcr = MDBS | OBPC | FSDA | FSCL; + ret = i2c_recover_bus(&priv->adap); + } + + return ret; +} + +static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv) +{ + u32 scgd, cdf, round, ick, sum, scl, cdf_width; + unsigned long rate; + struct device *dev = rcar_i2c_priv_to_dev(priv); + struct i2c_timings t = { + .bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ, + .scl_fall_ns = 35, + .scl_rise_ns = 200, + .scl_int_delay_ns = 50, + }; + + /* Fall back to previously used values if not supplied */ + i2c_parse_fw_timings(dev, &t, false); + + switch (priv->devtype) { + case I2C_RCAR_GEN1: + cdf_width = 2; + break; + case I2C_RCAR_GEN2: + case I2C_RCAR_GEN3: + cdf_width = 3; + break; + default: + dev_err(dev, "device type error\n"); + return -EIO; + } + + /* + * calculate SCL clock + * see + * ICCCR + * + * ick = clkp / (1 + CDF) + * SCL = ick / (20 + SCGD * 8 + F[(ticf + tr + intd) * ick]) + * + * ick : I2C internal clock < 20 MHz + * ticf : I2C SCL falling time + * tr : I2C SCL rising time + * intd : LSI internal delay + * clkp : peripheral_clk + * F[] : integer up-valuation + */ + rate = clk_get_rate(priv->clk); + cdf = rate / 20000000; + if (cdf >= 1U << cdf_width) { + dev_err(dev, "Input clock %lu too high\n", rate); + return -EIO; + } + ick = rate / (cdf + 1); + + /* + * it is impossible to calculate large scale + * number on u32. separate it + * + * F[(ticf + tr + intd) * ick] with sum = (ticf + tr + intd) + * = F[sum * ick / 1000000000] + * = F[(ick / 1000000) * sum / 1000] + */ + sum = t.scl_fall_ns + t.scl_rise_ns + t.scl_int_delay_ns; + round = (ick + 500000) / 1000000 * sum; + round = (round + 500) / 1000; + + /* + * SCL = ick / (20 + SCGD * 8 + F[(ticf + tr + intd) * ick]) + * + * Calculation result (= SCL) should be less than + * bus_speed for hardware safety + * + * We could use something along the lines of + * div = ick / (bus_speed + 1) + 1; + * scgd = (div - 20 - round + 7) / 8; + * scl = ick / (20 + (scgd * 8) + round); + * (not fully verified) but that would get pretty involved + */ + for (scgd = 0; scgd < 0x40; scgd++) { + scl = ick / (20 + (scgd * 8) + round); + if (scl <= t.bus_freq_hz) + goto scgd_find; + } + dev_err(dev, "it is impossible to calculate best SCL\n"); + return -EIO; + +scgd_find: + dev_dbg(dev, "clk %d/%d(%lu), round %u, CDF:0x%x, SCGD: 0x%x\n", + scl, t.bus_freq_hz, rate, round, cdf, scgd); + + /* keep icccr value */ + priv->icccr = scgd << cdf_width | cdf; + + return 0; +} + +/* + * We don't have a test case but the HW engineers say that the write order of + * ICMSR and ICMCR depends on whether we issue START or REP_START. So, ICMSR + * handling is outside of this function. First messages clear ICMSR before this + * function, interrupt handlers clear the relevant bits after this function. + */ +static void rcar_i2c_prepare_msg(struct rcar_i2c_priv *priv) +{ + int read = !!rcar_i2c_is_recv(priv); + bool rep_start = !(priv->flags & ID_REP_AFTER_RD); + + priv->pos = 0; + priv->flags &= ID_P_MASK; + + if (priv->msgs_left == 1) + priv->flags |= ID_LAST_MSG; + + rcar_i2c_write(priv, ICMAR, i2c_8bit_addr_from_msg(priv->msg)); + if (priv->flags & ID_P_NOT_ATOMIC) + rcar_i2c_write(priv, ICMIER, read ? RCAR_IRQ_RECV : RCAR_IRQ_SEND); + + if (rep_start) + rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_START); +} + +static void rcar_i2c_first_msg(struct rcar_i2c_priv *priv, + struct i2c_msg *msgs, int num) +{ + priv->msg = msgs; + priv->msgs_left = num; + rcar_i2c_write(priv, ICMSR, 0); /* must be before preparing msg */ + rcar_i2c_prepare_msg(priv); +} + +static void rcar_i2c_next_msg(struct rcar_i2c_priv *priv) +{ + priv->msg++; + priv->msgs_left--; + rcar_i2c_prepare_msg(priv); + /* ICMSR handling must come afterwards in the irq handler */ +} + +static void rcar_i2c_cleanup_dma(struct rcar_i2c_priv *priv, bool terminate) +{ + struct dma_chan *chan = priv->dma_direction == DMA_FROM_DEVICE + ? priv->dma_rx : priv->dma_tx; + + /* only allowed from thread context! */ + if (terminate) + dmaengine_terminate_sync(chan); + + dma_unmap_single(chan->device->dev, sg_dma_address(&priv->sg), + sg_dma_len(&priv->sg), priv->dma_direction); + + /* Gen3 can only do one RXDMA per transfer and we just completed it */ + if (priv->devtype == I2C_RCAR_GEN3 && + priv->dma_direction == DMA_FROM_DEVICE) + priv->flags |= ID_P_NO_RXDMA; + + priv->dma_direction = DMA_NONE; + + /* Disable DMA Master Received/Transmitted, must be last! */ + rcar_i2c_write(priv, ICDMAER, 0); +} + +static void rcar_i2c_dma_callback(void *data) +{ + struct rcar_i2c_priv *priv = data; + + priv->pos += sg_dma_len(&priv->sg); + + rcar_i2c_cleanup_dma(priv, false); +} + +static bool rcar_i2c_dma(struct rcar_i2c_priv *priv) +{ + struct device *dev = rcar_i2c_priv_to_dev(priv); + struct i2c_msg *msg = priv->msg; + bool read = msg->flags & I2C_M_RD; + enum dma_data_direction dir = read ? DMA_FROM_DEVICE : DMA_TO_DEVICE; + struct dma_chan *chan = read ? priv->dma_rx : priv->dma_tx; + struct dma_async_tx_descriptor *txdesc; + dma_addr_t dma_addr; + dma_cookie_t cookie; + unsigned char *buf; + int len; + + /* Do various checks to see if DMA is feasible at all */ + if (!(priv->flags & ID_P_NOT_ATOMIC) || IS_ERR(chan) || msg->len < RCAR_MIN_DMA_LEN || + !(msg->flags & I2C_M_DMA_SAFE) || (read && priv->flags & ID_P_NO_RXDMA)) + return false; + + if (read) { + /* + * The last two bytes needs to be fetched using PIO in + * order for the STOP phase to work. + */ + buf = priv->msg->buf; + len = priv->msg->len - 2; + } else { + /* + * First byte in message was sent using PIO. + */ + buf = priv->msg->buf + 1; + len = priv->msg->len - 1; + } + + dma_addr = dma_map_single(chan->device->dev, buf, len, dir); + if (dma_mapping_error(chan->device->dev, dma_addr)) { + dev_dbg(dev, "dma map failed, using PIO\n"); + return false; + } + + sg_dma_len(&priv->sg) = len; + sg_dma_address(&priv->sg) = dma_addr; + + priv->dma_direction = dir; + + txdesc = dmaengine_prep_slave_sg(chan, &priv->sg, 1, + read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!txdesc) { + dev_dbg(dev, "dma prep slave sg failed, using PIO\n"); + rcar_i2c_cleanup_dma(priv, false); + return false; + } + + txdesc->callback = rcar_i2c_dma_callback; + txdesc->callback_param = priv; + + cookie = dmaengine_submit(txdesc); + if (dma_submit_error(cookie)) { + dev_dbg(dev, "submitting dma failed, using PIO\n"); + rcar_i2c_cleanup_dma(priv, false); + return false; + } + + /* Enable DMA Master Received/Transmitted */ + if (read) + rcar_i2c_write(priv, ICDMAER, RMDMAE); + else + rcar_i2c_write(priv, ICDMAER, TMDMAE); + + dma_async_issue_pending(chan); + return true; +} + +static void rcar_i2c_irq_send(struct rcar_i2c_priv *priv, u32 msr) +{ + struct i2c_msg *msg = priv->msg; + u32 irqs_to_clear = MDE; + + /* FIXME: sometimes, unknown interrupt happened. Do nothing */ + if (!(msr & MDE)) + return; + + if (msr & MAT) + irqs_to_clear |= MAT; + + /* Check if DMA can be enabled and take over */ + if (priv->pos == 1 && rcar_i2c_dma(priv)) + return; + + if (priv->pos < msg->len) { + /* + * Prepare next data to ICRXTX register. + * This data will go to _SHIFT_ register. + * + * * + * [ICRXTX] -> [SHIFT] -> [I2C bus] + */ + rcar_i2c_write(priv, ICRXTX, msg->buf[priv->pos]); + priv->pos++; + } else { + /* + * The last data was pushed to ICRXTX on _PREV_ empty irq. + * It is on _SHIFT_ register, and will sent to I2C bus. + * + * * + * [ICRXTX] -> [SHIFT] -> [I2C bus] + */ + + if (priv->flags & ID_LAST_MSG) + /* + * If current msg is the _LAST_ msg, + * prepare stop condition here. + * ID_DONE will be set on STOP irq. + */ + rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP); + else + rcar_i2c_next_msg(priv); + } + + rcar_i2c_clear_irq(priv, irqs_to_clear); +} + +static void rcar_i2c_irq_recv(struct rcar_i2c_priv *priv, u32 msr) +{ + struct i2c_msg *msg = priv->msg; + bool recv_len_init = priv->pos == 0 && msg->flags & I2C_M_RECV_LEN; + u32 irqs_to_clear = MDR; + + /* FIXME: sometimes, unknown interrupt happened. Do nothing */ + if (!(msr & MDR)) + return; + + if (msr & MAT) { + irqs_to_clear |= MAT; + /* + * Address transfer phase finished, but no data at this point. + * Try to use DMA to receive data. + */ + rcar_i2c_dma(priv); + } else if (priv->pos < msg->len) { + /* get received data */ + u8 data = rcar_i2c_read(priv, ICRXTX); + + msg->buf[priv->pos] = data; + if (recv_len_init) { + if (data == 0 || data > I2C_SMBUS_BLOCK_MAX) { + priv->flags |= ID_DONE | ID_EPROTO; + return; + } + msg->len += msg->buf[0]; + /* Enough data for DMA? */ + if (rcar_i2c_dma(priv)) + return; + /* new length after RECV_LEN now properly initialized */ + recv_len_init = false; + } + priv->pos++; + } + + /* + * If next received data is the _LAST_ and we are not waiting for a new + * length because of RECV_LEN, then go to a new phase. + */ + if (priv->pos + 1 == msg->len && !recv_len_init) { + if (priv->flags & ID_LAST_MSG) { + rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP); + } else { + rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_START); + priv->flags |= ID_REP_AFTER_RD; + } + } + + if (priv->pos == msg->len && !(priv->flags & ID_LAST_MSG)) + rcar_i2c_next_msg(priv); + + rcar_i2c_clear_irq(priv, irqs_to_clear); +} + +static bool rcar_i2c_slave_irq(struct rcar_i2c_priv *priv) +{ + u32 ssr_raw, ssr_filtered; + u8 value; + + ssr_raw = rcar_i2c_read(priv, ICSSR) & 0xff; + ssr_filtered = ssr_raw & rcar_i2c_read(priv, ICSIER); + + if (!ssr_filtered) + return false; + + /* address detected */ + if (ssr_filtered & SAR) { + /* read or write request */ + if (ssr_raw & STM) { + i2c_slave_event(priv->slave, I2C_SLAVE_READ_REQUESTED, &value); + rcar_i2c_write(priv, ICRXTX, value); + rcar_i2c_write(priv, ICSIER, SDE | SSR | SAR); + } else { + i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_REQUESTED, &value); + rcar_i2c_read(priv, ICRXTX); /* dummy read */ + rcar_i2c_write(priv, ICSIER, SDR | SSR | SAR); + } + + /* Clear SSR, too, because of old STOPs to other clients than us */ + rcar_i2c_write(priv, ICSSR, ~(SAR | SSR) & 0xff); + } + + /* master sent stop */ + if (ssr_filtered & SSR) { + i2c_slave_event(priv->slave, I2C_SLAVE_STOP, &value); + rcar_i2c_write(priv, ICSCR, SIE | SDBS); /* clear our NACK */ + rcar_i2c_write(priv, ICSIER, SAR); + rcar_i2c_write(priv, ICSSR, ~SSR & 0xff); + } + + /* master wants to write to us */ + if (ssr_filtered & SDR) { + int ret; + + value = rcar_i2c_read(priv, ICRXTX); + ret = i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_RECEIVED, &value); + /* Send NACK in case of error */ + rcar_i2c_write(priv, ICSCR, SIE | SDBS | (ret < 0 ? FNA : 0)); + rcar_i2c_write(priv, ICSSR, ~SDR & 0xff); + } + + /* master wants to read from us */ + if (ssr_filtered & SDE) { + i2c_slave_event(priv->slave, I2C_SLAVE_READ_PROCESSED, &value); + rcar_i2c_write(priv, ICRXTX, value); + rcar_i2c_write(priv, ICSSR, ~SDE & 0xff); + } + + return true; +} + +/* + * This driver has a lock-free design because there are IP cores (at least + * R-Car Gen2) which have an inherent race condition in their hardware design. + * There, we need to switch to RCAR_BUS_PHASE_DATA as soon as possible after + * the interrupt was generated, otherwise an unwanted repeated message gets + * generated. It turned out that taking a spinlock at the beginning of the ISR + * was already causing repeated messages. Thus, this driver was converted to + * the now lockless behaviour. Please keep this in mind when hacking the driver. + * R-Car Gen3 seems to have this fixed but earlier versions than R-Car Gen2 are + * likely affected. Therefore, we have different interrupt handler entries. + */ +static irqreturn_t rcar_i2c_irq(int irq, struct rcar_i2c_priv *priv, u32 msr) +{ + if (!msr) { + if (rcar_i2c_slave_irq(priv)) + return IRQ_HANDLED; + + return IRQ_NONE; + } + + /* Arbitration lost */ + if (msr & MAL) { + priv->flags |= ID_DONE | ID_ARBLOST; + goto out; + } + + /* Nack */ + if (msr & MNR) { + /* HW automatically sends STOP after received NACK */ + if (priv->flags & ID_P_NOT_ATOMIC) + rcar_i2c_write(priv, ICMIER, RCAR_IRQ_STOP); + priv->flags |= ID_NACK; + goto out; + } + + /* Stop */ + if (msr & MST) { + priv->msgs_left--; /* The last message also made it */ + priv->flags |= ID_DONE; + goto out; + } + + if (rcar_i2c_is_recv(priv)) + rcar_i2c_irq_recv(priv, msr); + else + rcar_i2c_irq_send(priv, msr); + +out: + if (priv->flags & ID_DONE) { + rcar_i2c_write(priv, ICMIER, 0); + rcar_i2c_write(priv, ICMSR, 0); + if (priv->flags & ID_P_NOT_ATOMIC) + wake_up(&priv->wait); + } + + return IRQ_HANDLED; +} + +static irqreturn_t rcar_i2c_gen2_irq(int irq, void *ptr) +{ + struct rcar_i2c_priv *priv = ptr; + u32 msr; + + /* Clear START or STOP immediately, except for REPSTART after read */ + if (likely(!(priv->flags & ID_REP_AFTER_RD))) + rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA); + + /* Only handle interrupts that are currently enabled */ + msr = rcar_i2c_read(priv, ICMSR); + if (priv->flags & ID_P_NOT_ATOMIC) + msr &= rcar_i2c_read(priv, ICMIER); + + return rcar_i2c_irq(irq, priv, msr); +} + +static irqreturn_t rcar_i2c_gen3_irq(int irq, void *ptr) +{ + struct rcar_i2c_priv *priv = ptr; + u32 msr; + + /* Only handle interrupts that are currently enabled */ + msr = rcar_i2c_read(priv, ICMSR); + if (priv->flags & ID_P_NOT_ATOMIC) + msr &= rcar_i2c_read(priv, ICMIER); + + /* + * Clear START or STOP immediately, except for REPSTART after read or + * if a spurious interrupt was detected. + */ + if (likely(!(priv->flags & ID_REP_AFTER_RD) && msr)) + rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA); + + return rcar_i2c_irq(irq, priv, msr); +} + +static struct dma_chan *rcar_i2c_request_dma_chan(struct device *dev, + enum dma_transfer_direction dir, + dma_addr_t port_addr) +{ + struct dma_chan *chan; + struct dma_slave_config cfg; + char *chan_name = dir == DMA_MEM_TO_DEV ? "tx" : "rx"; + int ret; + + chan = dma_request_chan(dev, chan_name); + if (IS_ERR(chan)) { + dev_dbg(dev, "request_channel failed for %s (%ld)\n", + chan_name, PTR_ERR(chan)); + return chan; + } + + memset(&cfg, 0, sizeof(cfg)); + cfg.direction = dir; + if (dir == DMA_MEM_TO_DEV) { + cfg.dst_addr = port_addr; + cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + } else { + cfg.src_addr = port_addr; + cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + } + + ret = dmaengine_slave_config(chan, &cfg); + if (ret) { + dev_dbg(dev, "slave_config failed for %s (%d)\n", + chan_name, ret); + dma_release_channel(chan); + return ERR_PTR(ret); + } + + dev_dbg(dev, "got DMA channel for %s\n", chan_name); + return chan; +} + +static void rcar_i2c_request_dma(struct rcar_i2c_priv *priv, + struct i2c_msg *msg) +{ + struct device *dev = rcar_i2c_priv_to_dev(priv); + bool read; + struct dma_chan *chan; + enum dma_transfer_direction dir; + + read = msg->flags & I2C_M_RD; + + chan = read ? priv->dma_rx : priv->dma_tx; + if (PTR_ERR(chan) != -EPROBE_DEFER) + return; + + dir = read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV; + chan = rcar_i2c_request_dma_chan(dev, dir, priv->res->start + ICRXTX); + + if (read) + priv->dma_rx = chan; + else + priv->dma_tx = chan; +} + +static void rcar_i2c_release_dma(struct rcar_i2c_priv *priv) +{ + if (!IS_ERR(priv->dma_tx)) { + dma_release_channel(priv->dma_tx); + priv->dma_tx = ERR_PTR(-EPROBE_DEFER); + } + + if (!IS_ERR(priv->dma_rx)) { + dma_release_channel(priv->dma_rx); + priv->dma_rx = ERR_PTR(-EPROBE_DEFER); + } +} + +/* I2C is a special case, we need to poll the status of a reset */ +static int rcar_i2c_do_reset(struct rcar_i2c_priv *priv) +{ + int ret; + + ret = reset_control_reset(priv->rstc); + if (ret) + return ret; + + return read_poll_timeout_atomic(reset_control_status, ret, ret == 0, 1, + 100, false, priv->rstc); +} + +static int rcar_i2c_master_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, + int num) +{ + struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); + struct device *dev = rcar_i2c_priv_to_dev(priv); + int i, ret; + long time_left; + + priv->flags |= ID_P_NOT_ATOMIC; + + pm_runtime_get_sync(dev); + + /* Check bus state before init otherwise bus busy info will be lost */ + ret = rcar_i2c_bus_barrier(priv); + if (ret < 0) + goto out; + + /* Gen3 needs a reset before allowing RXDMA once */ + if (priv->devtype == I2C_RCAR_GEN3) { + priv->flags |= ID_P_NO_RXDMA; + if (!IS_ERR(priv->rstc)) { + ret = rcar_i2c_do_reset(priv); + if (ret == 0) + priv->flags &= ~ID_P_NO_RXDMA; + } + } + + rcar_i2c_init(priv); + + for (i = 0; i < num; i++) + rcar_i2c_request_dma(priv, msgs + i); + + rcar_i2c_first_msg(priv, msgs, num); + + time_left = wait_event_timeout(priv->wait, priv->flags & ID_DONE, + num * adap->timeout); + + /* cleanup DMA if it couldn't complete properly due to an error */ + if (priv->dma_direction != DMA_NONE) + rcar_i2c_cleanup_dma(priv, true); + + if (!time_left) { + rcar_i2c_init(priv); + ret = -ETIMEDOUT; + } else if (priv->flags & ID_NACK) { + ret = -ENXIO; + } else if (priv->flags & ID_ARBLOST) { + ret = -EAGAIN; + } else if (priv->flags & ID_EPROTO) { + ret = -EPROTO; + } else { + ret = num - priv->msgs_left; /* The number of transfer */ + } +out: + pm_runtime_put(dev); + + if (ret < 0 && ret != -ENXIO) + dev_err(dev, "error %d : %x\n", ret, priv->flags); + + return ret; +} + +static int rcar_i2c_master_xfer_atomic(struct i2c_adapter *adap, + struct i2c_msg *msgs, + int num) +{ + struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); + struct device *dev = rcar_i2c_priv_to_dev(priv); + unsigned long j; + bool time_left; + int ret; + + priv->flags &= ~ID_P_NOT_ATOMIC; + + pm_runtime_get_sync(dev); + + /* Check bus state before init otherwise bus busy info will be lost */ + ret = rcar_i2c_bus_barrier(priv); + if (ret < 0) + goto out; + + rcar_i2c_init(priv); + rcar_i2c_first_msg(priv, msgs, num); + + j = jiffies + num * adap->timeout; + do { + u32 msr = rcar_i2c_read(priv, ICMSR); + + msr &= (rcar_i2c_is_recv(priv) ? RCAR_IRQ_RECV : RCAR_IRQ_SEND) | RCAR_IRQ_STOP; + + if (msr) { + if (priv->devtype < I2C_RCAR_GEN3) + rcar_i2c_gen2_irq(0, priv); + else + rcar_i2c_gen3_irq(0, priv); + } + + time_left = time_before_eq(jiffies, j); + } while (!(priv->flags & ID_DONE) && time_left); + + if (!time_left) { + rcar_i2c_init(priv); + ret = -ETIMEDOUT; + } else if (priv->flags & ID_NACK) { + ret = -ENXIO; + } else if (priv->flags & ID_ARBLOST) { + ret = -EAGAIN; + } else if (priv->flags & ID_EPROTO) { + ret = -EPROTO; + } else { + ret = num - priv->msgs_left; /* The number of transfer */ + } +out: + pm_runtime_put(dev); + + if (ret < 0 && ret != -ENXIO) + dev_err(dev, "error %d : %x\n", ret, priv->flags); + + return ret; +} + +static int rcar_reg_slave(struct i2c_client *slave) +{ + struct rcar_i2c_priv *priv = i2c_get_adapdata(slave->adapter); + + if (priv->slave) + return -EBUSY; + + if (slave->flags & I2C_CLIENT_TEN) + return -EAFNOSUPPORT; + + /* Keep device active for slave address detection logic */ + pm_runtime_get_sync(rcar_i2c_priv_to_dev(priv)); + + priv->slave = slave; + rcar_i2c_write(priv, ICSAR, slave->addr); + rcar_i2c_write(priv, ICSSR, 0); + rcar_i2c_write(priv, ICSIER, SAR); + rcar_i2c_write(priv, ICSCR, SIE | SDBS); + + return 0; +} + +static int rcar_unreg_slave(struct i2c_client *slave) +{ + struct rcar_i2c_priv *priv = i2c_get_adapdata(slave->adapter); + + WARN_ON(!priv->slave); + + /* ensure no irq is running before clearing ptr */ + disable_irq(priv->irq); + rcar_i2c_write(priv, ICSIER, 0); + rcar_i2c_write(priv, ICSSR, 0); + enable_irq(priv->irq); + rcar_i2c_write(priv, ICSCR, SDBS); + rcar_i2c_write(priv, ICSAR, 0); /* Gen2: must be 0 if not using slave */ + + priv->slave = NULL; + + pm_runtime_put(rcar_i2c_priv_to_dev(priv)); + + return 0; +} + +static u32 rcar_i2c_func(struct i2c_adapter *adap) +{ + struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); + + /* + * This HW can't do: + * I2C_SMBUS_QUICK (setting FSB during START didn't work) + * I2C_M_NOSTART (automatically sends address after START) + * I2C_M_IGNORE_NAK (automatically sends STOP after NAK) + */ + u32 func = I2C_FUNC_I2C | I2C_FUNC_SLAVE | + (I2C_FUNC_SMBUS_EMUL_ALL & ~I2C_FUNC_SMBUS_QUICK); + + if (priv->flags & ID_P_HOST_NOTIFY) + func |= I2C_FUNC_SMBUS_HOST_NOTIFY; + + return func; +} + +static const struct i2c_algorithm rcar_i2c_algo = { + .master_xfer = rcar_i2c_master_xfer, + .master_xfer_atomic = rcar_i2c_master_xfer_atomic, + .functionality = rcar_i2c_func, + .reg_slave = rcar_reg_slave, + .unreg_slave = rcar_unreg_slave, +}; + +static const struct i2c_adapter_quirks rcar_i2c_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN, +}; + +static const struct of_device_id rcar_i2c_dt_ids[] = { + { .compatible = "renesas,i2c-r8a7778", .data = (void *)I2C_RCAR_GEN1 }, + { .compatible = "renesas,i2c-r8a7779", .data = (void *)I2C_RCAR_GEN1 }, + { .compatible = "renesas,i2c-r8a7790", .data = (void *)I2C_RCAR_GEN2 }, + { .compatible = "renesas,i2c-r8a7791", .data = (void *)I2C_RCAR_GEN2 }, + { .compatible = "renesas,i2c-r8a7792", .data = (void *)I2C_RCAR_GEN2 }, + { .compatible = "renesas,i2c-r8a7793", .data = (void *)I2C_RCAR_GEN2 }, + { .compatible = "renesas,i2c-r8a7794", .data = (void *)I2C_RCAR_GEN2 }, + { .compatible = "renesas,i2c-r8a7795", .data = (void *)I2C_RCAR_GEN3 }, + { .compatible = "renesas,i2c-r8a7796", .data = (void *)I2C_RCAR_GEN3 }, + { .compatible = "renesas,rcar-gen1-i2c", .data = (void *)I2C_RCAR_GEN1 }, + { .compatible = "renesas,rcar-gen2-i2c", .data = (void *)I2C_RCAR_GEN2 }, + { .compatible = "renesas,rcar-gen3-i2c", .data = (void *)I2C_RCAR_GEN3 }, + { .compatible = "renesas,rcar-gen4-i2c", .data = (void *)I2C_RCAR_GEN3 }, + {}, +}; +MODULE_DEVICE_TABLE(of, rcar_i2c_dt_ids); + +static int rcar_i2c_probe(struct platform_device *pdev) +{ + struct rcar_i2c_priv *priv; + struct i2c_adapter *adap; + struct device *dev = &pdev->dev; + unsigned long irqflags = 0; + irqreturn_t (*irqhandler)(int irq, void *ptr) = rcar_i2c_gen3_irq; + int ret; + + /* Otherwise logic will break because some bytes must always use PIO */ + BUILD_BUG_ON_MSG(RCAR_MIN_DMA_LEN < 3, "Invalid min DMA length"); + + priv = devm_kzalloc(dev, sizeof(struct rcar_i2c_priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->clk = devm_clk_get(dev, NULL); + if (IS_ERR(priv->clk)) { + dev_err(dev, "cannot get clock\n"); + return PTR_ERR(priv->clk); + } + + priv->io = devm_platform_get_and_ioremap_resource(pdev, 0, &priv->res); + if (IS_ERR(priv->io)) + return PTR_ERR(priv->io); + + priv->devtype = (enum rcar_i2c_type)of_device_get_match_data(dev); + init_waitqueue_head(&priv->wait); + + adap = &priv->adap; + adap->nr = pdev->id; + adap->algo = &rcar_i2c_algo; + adap->class = I2C_CLASS_DEPRECATED; + adap->retries = 3; + adap->dev.parent = dev; + adap->dev.of_node = dev->of_node; + adap->bus_recovery_info = &rcar_i2c_bri; + adap->quirks = &rcar_i2c_quirks; + i2c_set_adapdata(adap, priv); + strscpy(adap->name, pdev->name, sizeof(adap->name)); + + /* Init DMA */ + sg_init_table(&priv->sg, 1); + priv->dma_direction = DMA_NONE; + priv->dma_rx = priv->dma_tx = ERR_PTR(-EPROBE_DEFER); + + /* Activate device for clock calculation */ + pm_runtime_enable(dev); + pm_runtime_get_sync(dev); + ret = rcar_i2c_clock_calculate(priv); + if (ret < 0) { + pm_runtime_put(dev); + goto out_pm_disable; + } + + rcar_i2c_write(priv, ICSAR, 0); /* Gen2: must be 0 if not using slave */ + + if (priv->devtype < I2C_RCAR_GEN3) { + irqflags |= IRQF_NO_THREAD; + irqhandler = rcar_i2c_gen2_irq; + } + + if (priv->devtype == I2C_RCAR_GEN3) { + priv->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL); + if (!IS_ERR(priv->rstc)) { + ret = reset_control_status(priv->rstc); + if (ret < 0) + priv->rstc = ERR_PTR(-ENOTSUPP); + } + } + + /* Stay always active when multi-master to keep arbitration working */ + if (of_property_read_bool(dev->of_node, "multi-master")) + priv->flags |= ID_P_PM_BLOCKED; + else + pm_runtime_put(dev); + + if (of_property_read_bool(dev->of_node, "smbus")) + priv->flags |= ID_P_HOST_NOTIFY; + + ret = platform_get_irq(pdev, 0); + if (ret < 0) + goto out_pm_put; + priv->irq = ret; + ret = devm_request_irq(dev, priv->irq, irqhandler, irqflags, dev_name(dev), priv); + if (ret < 0) { + dev_err(dev, "cannot get irq %d\n", priv->irq); + goto out_pm_put; + } + + platform_set_drvdata(pdev, priv); + + ret = i2c_add_numbered_adapter(adap); + if (ret < 0) + goto out_pm_put; + + if (priv->flags & ID_P_HOST_NOTIFY) { + priv->host_notify_client = i2c_new_slave_host_notify_device(adap); + if (IS_ERR(priv->host_notify_client)) { + ret = PTR_ERR(priv->host_notify_client); + goto out_del_device; + } + } + + dev_info(dev, "probed\n"); + + return 0; + + out_del_device: + i2c_del_adapter(&priv->adap); + out_pm_put: + if (priv->flags & ID_P_PM_BLOCKED) + pm_runtime_put(dev); + out_pm_disable: + pm_runtime_disable(dev); + return ret; +} + +static void rcar_i2c_remove(struct platform_device *pdev) +{ + struct rcar_i2c_priv *priv = platform_get_drvdata(pdev); + struct device *dev = &pdev->dev; + + if (priv->host_notify_client) + i2c_free_slave_host_notify_device(priv->host_notify_client); + i2c_del_adapter(&priv->adap); + rcar_i2c_release_dma(priv); + if (priv->flags & ID_P_PM_BLOCKED) + pm_runtime_put(dev); + pm_runtime_disable(dev); +} + +static int rcar_i2c_suspend(struct device *dev) +{ + struct rcar_i2c_priv *priv = dev_get_drvdata(dev); + + i2c_mark_adapter_suspended(&priv->adap); + return 0; +} + +static int rcar_i2c_resume(struct device *dev) +{ + struct rcar_i2c_priv *priv = dev_get_drvdata(dev); + + i2c_mark_adapter_resumed(&priv->adap); + return 0; +} + +static const struct dev_pm_ops rcar_i2c_pm_ops = { + NOIRQ_SYSTEM_SLEEP_PM_OPS(rcar_i2c_suspend, rcar_i2c_resume) +}; + +static struct platform_driver rcar_i2c_driver = { + .driver = { + .name = "i2c-rcar", + .of_match_table = rcar_i2c_dt_ids, + .pm = pm_sleep_ptr(&rcar_i2c_pm_ops), + }, + .probe = rcar_i2c_probe, + .remove_new = rcar_i2c_remove, +}; + +module_platform_driver(rcar_i2c_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Renesas R-Car I2C bus driver"); +MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>"); diff --git a/drivers/i2c/busses/i2c-riic.c b/drivers/i2c/busses/i2c-riic.c new file mode 100644 index 000000000..f0ee8871d --- /dev/null +++ b/drivers/i2c/busses/i2c-riic.c @@ -0,0 +1,509 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Renesas RIIC driver + * + * Copyright (C) 2013 Wolfram Sang <wsa@sang-engineering.com> + * Copyright (C) 2013 Renesas Solutions Corp. + */ + +/* + * This i2c core has a lot of interrupts, namely 8. We use their chaining as + * some kind of state machine. + * + * 1) The main xfer routine kicks off a transmission by putting the start bit + * (or repeated start) on the bus and enabling the transmit interrupt (TIE) + * since we need to send the slave address + RW bit in every case. + * + * 2) TIE sends slave address + RW bit and selects how to continue. + * + * 3a) Write case: We keep utilizing TIE as long as we have data to send. If we + * are done, we switch over to the transmission done interrupt (TEIE) and mark + * the message as completed (includes sending STOP) there. + * + * 3b) Read case: We switch over to receive interrupt (RIE). One dummy read is + * needed to start clocking, then we keep receiving until we are done. Note + * that we use the RDRFS mode all the time, i.e. we ACK/NACK every byte by + * writing to the ACKBT bit. I tried using the RDRFS mode only at the end of a + * message to create the final NACK as sketched in the datasheet. This caused + * some subtle races (when byte n was processed and byte n+1 was already + * waiting), though, and I started with the safe approach. + * + * 4) If we got a NACK somewhere, we flag the error and stop the transmission + * via NAKIE. + * + * Also check the comments in the interrupt routines for some gory details. + */ + +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/reset.h> + +#define RIIC_ICCR1 0x00 +#define RIIC_ICCR2 0x04 +#define RIIC_ICMR1 0x08 +#define RIIC_ICMR3 0x10 +#define RIIC_ICSER 0x18 +#define RIIC_ICIER 0x1c +#define RIIC_ICSR2 0x24 +#define RIIC_ICBRL 0x34 +#define RIIC_ICBRH 0x38 +#define RIIC_ICDRT 0x3c +#define RIIC_ICDRR 0x40 + +#define ICCR1_ICE 0x80 +#define ICCR1_IICRST 0x40 +#define ICCR1_SOWP 0x10 + +#define ICCR2_BBSY 0x80 +#define ICCR2_SP 0x08 +#define ICCR2_RS 0x04 +#define ICCR2_ST 0x02 + +#define ICMR1_CKS_MASK 0x70 +#define ICMR1_BCWP 0x08 +#define ICMR1_CKS(_x) ((((_x) << 4) & ICMR1_CKS_MASK) | ICMR1_BCWP) + +#define ICMR3_RDRFS 0x20 +#define ICMR3_ACKWP 0x10 +#define ICMR3_ACKBT 0x08 + +#define ICIER_TIE 0x80 +#define ICIER_TEIE 0x40 +#define ICIER_RIE 0x20 +#define ICIER_NAKIE 0x10 +#define ICIER_SPIE 0x08 + +#define ICSR2_NACKF 0x10 + +#define ICBR_RESERVED 0xe0 /* Should be 1 on writes */ + +#define RIIC_INIT_MSG -1 + +struct riic_dev { + void __iomem *base; + u8 *buf; + struct i2c_msg *msg; + int bytes_left; + int err; + int is_last; + struct completion msg_done; + struct i2c_adapter adapter; + struct clk *clk; +}; + +struct riic_irq_desc { + int res_num; + irq_handler_t isr; + char *name; +}; + +static inline void riic_clear_set_bit(struct riic_dev *riic, u8 clear, u8 set, u8 reg) +{ + writeb((readb(riic->base + reg) & ~clear) | set, riic->base + reg); +} + +static int riic_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + struct riic_dev *riic = i2c_get_adapdata(adap); + unsigned long time_left; + int i; + u8 start_bit; + + pm_runtime_get_sync(adap->dev.parent); + + if (readb(riic->base + RIIC_ICCR2) & ICCR2_BBSY) { + riic->err = -EBUSY; + goto out; + } + + reinit_completion(&riic->msg_done); + riic->err = 0; + + writeb(0, riic->base + RIIC_ICSR2); + + for (i = 0, start_bit = ICCR2_ST; i < num; i++) { + riic->bytes_left = RIIC_INIT_MSG; + riic->buf = msgs[i].buf; + riic->msg = &msgs[i]; + riic->is_last = (i == num - 1); + + writeb(ICIER_NAKIE | ICIER_TIE, riic->base + RIIC_ICIER); + + writeb(start_bit, riic->base + RIIC_ICCR2); + + time_left = wait_for_completion_timeout(&riic->msg_done, riic->adapter.timeout); + if (time_left == 0) + riic->err = -ETIMEDOUT; + + if (riic->err) + break; + + start_bit = ICCR2_RS; + } + + out: + pm_runtime_put(adap->dev.parent); + + return riic->err ?: num; +} + +static irqreturn_t riic_tdre_isr(int irq, void *data) +{ + struct riic_dev *riic = data; + u8 val; + + if (!riic->bytes_left) + return IRQ_NONE; + + if (riic->bytes_left == RIIC_INIT_MSG) { + if (riic->msg->flags & I2C_M_RD) + /* On read, switch over to receive interrupt */ + riic_clear_set_bit(riic, ICIER_TIE, ICIER_RIE, RIIC_ICIER); + else + /* On write, initialize length */ + riic->bytes_left = riic->msg->len; + + val = i2c_8bit_addr_from_msg(riic->msg); + } else { + val = *riic->buf; + riic->buf++; + riic->bytes_left--; + } + + /* + * Switch to transmission ended interrupt when done. Do check here + * after bytes_left was initialized to support SMBUS_QUICK (new msg has + * 0 length then) + */ + if (riic->bytes_left == 0) + riic_clear_set_bit(riic, ICIER_TIE, ICIER_TEIE, RIIC_ICIER); + + /* + * This acks the TIE interrupt. We get another TIE immediately if our + * value could be moved to the shadow shift register right away. So + * this must be after updates to ICIER (where we want to disable TIE)! + */ + writeb(val, riic->base + RIIC_ICDRT); + + return IRQ_HANDLED; +} + +static irqreturn_t riic_tend_isr(int irq, void *data) +{ + struct riic_dev *riic = data; + + if (readb(riic->base + RIIC_ICSR2) & ICSR2_NACKF) { + /* We got a NACKIE */ + readb(riic->base + RIIC_ICDRR); /* dummy read */ + riic_clear_set_bit(riic, ICSR2_NACKF, 0, RIIC_ICSR2); + riic->err = -ENXIO; + } else if (riic->bytes_left) { + return IRQ_NONE; + } + + if (riic->is_last || riic->err) { + riic_clear_set_bit(riic, ICIER_TEIE, ICIER_SPIE, RIIC_ICIER); + writeb(ICCR2_SP, riic->base + RIIC_ICCR2); + } else { + /* Transfer is complete, but do not send STOP */ + riic_clear_set_bit(riic, ICIER_TEIE, 0, RIIC_ICIER); + complete(&riic->msg_done); + } + + return IRQ_HANDLED; +} + +static irqreturn_t riic_rdrf_isr(int irq, void *data) +{ + struct riic_dev *riic = data; + + if (!riic->bytes_left) + return IRQ_NONE; + + if (riic->bytes_left == RIIC_INIT_MSG) { + riic->bytes_left = riic->msg->len; + readb(riic->base + RIIC_ICDRR); /* dummy read */ + return IRQ_HANDLED; + } + + if (riic->bytes_left == 1) { + /* STOP must come before we set ACKBT! */ + if (riic->is_last) { + riic_clear_set_bit(riic, 0, ICIER_SPIE, RIIC_ICIER); + writeb(ICCR2_SP, riic->base + RIIC_ICCR2); + } + + riic_clear_set_bit(riic, 0, ICMR3_ACKBT, RIIC_ICMR3); + + } else { + riic_clear_set_bit(riic, ICMR3_ACKBT, 0, RIIC_ICMR3); + } + + /* Reading acks the RIE interrupt */ + *riic->buf = readb(riic->base + RIIC_ICDRR); + riic->buf++; + riic->bytes_left--; + + return IRQ_HANDLED; +} + +static irqreturn_t riic_stop_isr(int irq, void *data) +{ + struct riic_dev *riic = data; + + /* read back registers to confirm writes have fully propagated */ + writeb(0, riic->base + RIIC_ICSR2); + readb(riic->base + RIIC_ICSR2); + writeb(0, riic->base + RIIC_ICIER); + readb(riic->base + RIIC_ICIER); + + complete(&riic->msg_done); + + return IRQ_HANDLED; +} + +static u32 riic_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm riic_algo = { + .master_xfer = riic_xfer, + .functionality = riic_func, +}; + +static int riic_init_hw(struct riic_dev *riic, struct i2c_timings *t) +{ + int ret = 0; + unsigned long rate; + int total_ticks, cks, brl, brh; + + pm_runtime_get_sync(riic->adapter.dev.parent); + + if (t->bus_freq_hz > I2C_MAX_FAST_MODE_FREQ) { + dev_err(&riic->adapter.dev, + "unsupported bus speed (%dHz). %d max\n", + t->bus_freq_hz, I2C_MAX_FAST_MODE_FREQ); + ret = -EINVAL; + goto out; + } + + rate = clk_get_rate(riic->clk); + + /* + * Assume the default register settings: + * FER.SCLE = 1 (SCL sync circuit enabled, adds 2 or 3 cycles) + * FER.NFE = 1 (noise circuit enabled) + * MR3.NF = 0 (1 cycle of noise filtered out) + * + * Freq (CKS=000) = (I2CCLK + tr + tf)/ (BRH + 3 + 1) + (BRL + 3 + 1) + * Freq (CKS!=000) = (I2CCLK + tr + tf)/ (BRH + 2 + 1) + (BRL + 2 + 1) + */ + + /* + * Determine reference clock rate. We must be able to get the desired + * frequency with only 62 clock ticks max (31 high, 31 low). + * Aim for a duty of 60% LOW, 40% HIGH. + */ + total_ticks = DIV_ROUND_UP(rate, t->bus_freq_hz); + + for (cks = 0; cks < 7; cks++) { + /* + * 60% low time must be less than BRL + 2 + 1 + * BRL max register value is 0x1F. + */ + brl = ((total_ticks * 6) / 10); + if (brl <= (0x1F + 3)) + break; + + total_ticks /= 2; + rate /= 2; + } + + if (brl > (0x1F + 3)) { + dev_err(&riic->adapter.dev, "invalid speed (%lu). Too slow.\n", + (unsigned long)t->bus_freq_hz); + ret = -EINVAL; + goto out; + } + + brh = total_ticks - brl; + + /* Remove automatic clock ticks for sync circuit and NF */ + if (cks == 0) { + brl -= 4; + brh -= 4; + } else { + brl -= 3; + brh -= 3; + } + + /* + * Remove clock ticks for rise and fall times. Convert ns to clock + * ticks. + */ + brl -= t->scl_fall_ns / (1000000000 / rate); + brh -= t->scl_rise_ns / (1000000000 / rate); + + /* Adjust for min register values for when SCLE=1 and NFE=1 */ + if (brl < 1) + brl = 1; + if (brh < 1) + brh = 1; + + pr_debug("i2c-riic: freq=%lu, duty=%d, fall=%lu, rise=%lu, cks=%d, brl=%d, brh=%d\n", + rate / total_ticks, ((brl + 3) * 100) / (brl + brh + 6), + t->scl_fall_ns / (1000000000 / rate), + t->scl_rise_ns / (1000000000 / rate), cks, brl, brh); + + /* Changing the order of accessing IICRST and ICE may break things! */ + writeb(ICCR1_IICRST | ICCR1_SOWP, riic->base + RIIC_ICCR1); + riic_clear_set_bit(riic, 0, ICCR1_ICE, RIIC_ICCR1); + + writeb(ICMR1_CKS(cks), riic->base + RIIC_ICMR1); + writeb(brh | ICBR_RESERVED, riic->base + RIIC_ICBRH); + writeb(brl | ICBR_RESERVED, riic->base + RIIC_ICBRL); + + writeb(0, riic->base + RIIC_ICSER); + writeb(ICMR3_ACKWP | ICMR3_RDRFS, riic->base + RIIC_ICMR3); + + riic_clear_set_bit(riic, ICCR1_IICRST, 0, RIIC_ICCR1); + +out: + pm_runtime_put(riic->adapter.dev.parent); + return ret; +} + +static struct riic_irq_desc riic_irqs[] = { + { .res_num = 0, .isr = riic_tend_isr, .name = "riic-tend" }, + { .res_num = 1, .isr = riic_rdrf_isr, .name = "riic-rdrf" }, + { .res_num = 2, .isr = riic_tdre_isr, .name = "riic-tdre" }, + { .res_num = 3, .isr = riic_stop_isr, .name = "riic-stop" }, + { .res_num = 5, .isr = riic_tend_isr, .name = "riic-nack" }, +}; + +static void riic_reset_control_assert(void *data) +{ + reset_control_assert(data); +} + +static int riic_i2c_probe(struct platform_device *pdev) +{ + struct riic_dev *riic; + struct i2c_adapter *adap; + struct i2c_timings i2c_t; + struct reset_control *rstc; + int i, ret; + + riic = devm_kzalloc(&pdev->dev, sizeof(*riic), GFP_KERNEL); + if (!riic) + return -ENOMEM; + + riic->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(riic->base)) + return PTR_ERR(riic->base); + + riic->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(riic->clk)) { + dev_err(&pdev->dev, "missing controller clock"); + return PTR_ERR(riic->clk); + } + + rstc = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL); + if (IS_ERR(rstc)) + return dev_err_probe(&pdev->dev, PTR_ERR(rstc), + "Error: missing reset ctrl\n"); + + ret = reset_control_deassert(rstc); + if (ret) + return ret; + + ret = devm_add_action_or_reset(&pdev->dev, riic_reset_control_assert, rstc); + if (ret) + return ret; + + for (i = 0; i < ARRAY_SIZE(riic_irqs); i++) { + ret = platform_get_irq(pdev, riic_irqs[i].res_num); + if (ret < 0) + return ret; + + ret = devm_request_irq(&pdev->dev, ret, riic_irqs[i].isr, + 0, riic_irqs[i].name, riic); + if (ret) { + dev_err(&pdev->dev, "failed to request irq %s\n", riic_irqs[i].name); + return ret; + } + } + + adap = &riic->adapter; + i2c_set_adapdata(adap, riic); + strscpy(adap->name, "Renesas RIIC adapter", sizeof(adap->name)); + adap->owner = THIS_MODULE; + adap->algo = &riic_algo; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + + init_completion(&riic->msg_done); + + i2c_parse_fw_timings(&pdev->dev, &i2c_t, true); + + pm_runtime_enable(&pdev->dev); + + ret = riic_init_hw(riic, &i2c_t); + if (ret) + goto out; + + ret = i2c_add_adapter(adap); + if (ret) + goto out; + + platform_set_drvdata(pdev, riic); + + dev_info(&pdev->dev, "registered with %dHz bus speed\n", + i2c_t.bus_freq_hz); + return 0; + +out: + pm_runtime_disable(&pdev->dev); + return ret; +} + +static void riic_i2c_remove(struct platform_device *pdev) +{ + struct riic_dev *riic = platform_get_drvdata(pdev); + + pm_runtime_get_sync(&pdev->dev); + writeb(0, riic->base + RIIC_ICIER); + pm_runtime_put(&pdev->dev); + i2c_del_adapter(&riic->adapter); + pm_runtime_disable(&pdev->dev); +} + +static const struct of_device_id riic_i2c_dt_ids[] = { + { .compatible = "renesas,riic-rz", }, + { /* Sentinel */ }, +}; + +static struct platform_driver riic_i2c_driver = { + .probe = riic_i2c_probe, + .remove_new = riic_i2c_remove, + .driver = { + .name = "i2c-riic", + .of_match_table = riic_i2c_dt_ids, + }, +}; + +module_platform_driver(riic_i2c_driver); + +MODULE_DESCRIPTION("Renesas RIIC adapter"); +MODULE_AUTHOR("Wolfram Sang <wsa@sang-engineering.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_DEVICE_TABLE(of, riic_i2c_dt_ids); diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c new file mode 100644 index 000000000..4362db7c5 --- /dev/null +++ b/drivers/i2c/busses/i2c-rk3x.c @@ -0,0 +1,1411 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for I2C adapter in Rockchip RK3xxx SoC + * + * Max Schwarz <max.schwarz@online.de> + * based on the patches by Rockchip Inc. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/iopoll.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/spinlock.h> +#include <linux/clk.h> +#include <linux/wait.h> +#include <linux/mfd/syscon.h> +#include <linux/regmap.h> +#include <linux/math64.h> + + +/* Register Map */ +#define REG_CON 0x00 /* control register */ +#define REG_CLKDIV 0x04 /* clock divisor register */ +#define REG_MRXADDR 0x08 /* slave address for REGISTER_TX */ +#define REG_MRXRADDR 0x0c /* slave register address for REGISTER_TX */ +#define REG_MTXCNT 0x10 /* number of bytes to be transmitted */ +#define REG_MRXCNT 0x14 /* number of bytes to be received */ +#define REG_IEN 0x18 /* interrupt enable */ +#define REG_IPD 0x1c /* interrupt pending */ +#define REG_FCNT 0x20 /* finished count */ + +/* Data buffer offsets */ +#define TXBUFFER_BASE 0x100 +#define RXBUFFER_BASE 0x200 + +/* REG_CON bits */ +#define REG_CON_EN BIT(0) +enum { + REG_CON_MOD_TX = 0, /* transmit data */ + REG_CON_MOD_REGISTER_TX, /* select register and restart */ + REG_CON_MOD_RX, /* receive data */ + REG_CON_MOD_REGISTER_RX, /* broken: transmits read addr AND writes + * register addr */ +}; +#define REG_CON_MOD(mod) ((mod) << 1) +#define REG_CON_MOD_MASK (BIT(1) | BIT(2)) +#define REG_CON_START BIT(3) +#define REG_CON_STOP BIT(4) +#define REG_CON_LASTACK BIT(5) /* 1: send NACK after last received byte */ +#define REG_CON_ACTACK BIT(6) /* 1: stop if NACK is received */ + +#define REG_CON_TUNING_MASK GENMASK_ULL(15, 8) + +#define REG_CON_SDA_CFG(cfg) ((cfg) << 8) +#define REG_CON_STA_CFG(cfg) ((cfg) << 12) +#define REG_CON_STO_CFG(cfg) ((cfg) << 14) + +/* REG_MRXADDR bits */ +#define REG_MRXADDR_VALID(x) BIT(24 + (x)) /* [x*8+7:x*8] of MRX[R]ADDR valid */ + +/* REG_IEN/REG_IPD bits */ +#define REG_INT_BTF BIT(0) /* a byte was transmitted */ +#define REG_INT_BRF BIT(1) /* a byte was received */ +#define REG_INT_MBTF BIT(2) /* master data transmit finished */ +#define REG_INT_MBRF BIT(3) /* master data receive finished */ +#define REG_INT_START BIT(4) /* START condition generated */ +#define REG_INT_STOP BIT(5) /* STOP condition generated */ +#define REG_INT_NAKRCV BIT(6) /* NACK received */ +#define REG_INT_ALL 0x7f + +/* Constants */ +#define WAIT_TIMEOUT 1000 /* ms */ +#define DEFAULT_SCL_RATE (100 * 1000) /* Hz */ + +/** + * struct i2c_spec_values - I2C specification values for various modes + * @min_hold_start_ns: min hold time (repeated) START condition + * @min_low_ns: min LOW period of the SCL clock + * @min_high_ns: min HIGH period of the SCL cloc + * @min_setup_start_ns: min set-up time for a repeated START conditio + * @max_data_hold_ns: max data hold time + * @min_data_setup_ns: min data set-up time + * @min_setup_stop_ns: min set-up time for STOP condition + * @min_hold_buffer_ns: min bus free time between a STOP and + * START condition + */ +struct i2c_spec_values { + unsigned long min_hold_start_ns; + unsigned long min_low_ns; + unsigned long min_high_ns; + unsigned long min_setup_start_ns; + unsigned long max_data_hold_ns; + unsigned long min_data_setup_ns; + unsigned long min_setup_stop_ns; + unsigned long min_hold_buffer_ns; +}; + +static const struct i2c_spec_values standard_mode_spec = { + .min_hold_start_ns = 4000, + .min_low_ns = 4700, + .min_high_ns = 4000, + .min_setup_start_ns = 4700, + .max_data_hold_ns = 3450, + .min_data_setup_ns = 250, + .min_setup_stop_ns = 4000, + .min_hold_buffer_ns = 4700, +}; + +static const struct i2c_spec_values fast_mode_spec = { + .min_hold_start_ns = 600, + .min_low_ns = 1300, + .min_high_ns = 600, + .min_setup_start_ns = 600, + .max_data_hold_ns = 900, + .min_data_setup_ns = 100, + .min_setup_stop_ns = 600, + .min_hold_buffer_ns = 1300, +}; + +static const struct i2c_spec_values fast_mode_plus_spec = { + .min_hold_start_ns = 260, + .min_low_ns = 500, + .min_high_ns = 260, + .min_setup_start_ns = 260, + .max_data_hold_ns = 400, + .min_data_setup_ns = 50, + .min_setup_stop_ns = 260, + .min_hold_buffer_ns = 500, +}; + +/** + * struct rk3x_i2c_calced_timings - calculated V1 timings + * @div_low: Divider output for low + * @div_high: Divider output for high + * @tuning: Used to adjust setup/hold data time, + * setup/hold start time and setup stop time for + * v1's calc_timings, the tuning should all be 0 + * for old hardware anyone using v0's calc_timings. + */ +struct rk3x_i2c_calced_timings { + unsigned long div_low; + unsigned long div_high; + unsigned int tuning; +}; + +enum rk3x_i2c_state { + STATE_IDLE, + STATE_START, + STATE_READ, + STATE_WRITE, + STATE_STOP +}; + +/** + * struct rk3x_i2c_soc_data - SOC-specific data + * @grf_offset: offset inside the grf regmap for setting the i2c type + * @calc_timings: Callback function for i2c timing information calculated + */ +struct rk3x_i2c_soc_data { + int grf_offset; + int (*calc_timings)(unsigned long, struct i2c_timings *, + struct rk3x_i2c_calced_timings *); +}; + +/** + * struct rk3x_i2c - private data of the controller + * @adap: corresponding I2C adapter + * @dev: device for this controller + * @soc_data: related soc data struct + * @regs: virtual memory area + * @clk: function clk for rk3399 or function & Bus clks for others + * @pclk: Bus clk for rk3399 + * @clk_rate_nb: i2c clk rate change notify + * @irq: irq number + * @t: I2C known timing information + * @lock: spinlock for the i2c bus + * @wait: the waitqueue to wait for i2c transfer + * @busy: the condition for the event to wait for + * @msg: current i2c message + * @addr: addr of i2c slave device + * @mode: mode of i2c transfer + * @is_last_msg: flag determines whether it is the last msg in this transfer + * @state: state of i2c transfer + * @processed: byte length which has been send or received + * @error: error code for i2c transfer + */ +struct rk3x_i2c { + struct i2c_adapter adap; + struct device *dev; + const struct rk3x_i2c_soc_data *soc_data; + + /* Hardware resources */ + void __iomem *regs; + struct clk *clk; + struct clk *pclk; + struct notifier_block clk_rate_nb; + int irq; + + /* Settings */ + struct i2c_timings t; + + /* Synchronization & notification */ + spinlock_t lock; + wait_queue_head_t wait; + bool busy; + + /* Current message */ + struct i2c_msg *msg; + u8 addr; + unsigned int mode; + bool is_last_msg; + + /* I2C state machine */ + enum rk3x_i2c_state state; + unsigned int processed; + int error; +}; + +static inline void i2c_writel(struct rk3x_i2c *i2c, u32 value, + unsigned int offset) +{ + writel(value, i2c->regs + offset); +} + +static inline u32 i2c_readl(struct rk3x_i2c *i2c, unsigned int offset) +{ + return readl(i2c->regs + offset); +} + +/* Reset all interrupt pending bits */ +static inline void rk3x_i2c_clean_ipd(struct rk3x_i2c *i2c) +{ + i2c_writel(i2c, REG_INT_ALL, REG_IPD); +} + +/** + * rk3x_i2c_start - Generate a START condition, which triggers a REG_INT_START interrupt. + * @i2c: target controller data + */ +static void rk3x_i2c_start(struct rk3x_i2c *i2c) +{ + u32 val = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK; + + i2c_writel(i2c, REG_INT_START, REG_IEN); + + /* enable adapter with correct mode, send START condition */ + val |= REG_CON_EN | REG_CON_MOD(i2c->mode) | REG_CON_START; + + /* if we want to react to NACK, set ACTACK bit */ + if (!(i2c->msg->flags & I2C_M_IGNORE_NAK)) + val |= REG_CON_ACTACK; + + i2c_writel(i2c, val, REG_CON); +} + +/** + * rk3x_i2c_stop - Generate a STOP condition, which triggers a REG_INT_STOP interrupt. + * @i2c: target controller data + * @error: Error code to return in rk3x_i2c_xfer + */ +static void rk3x_i2c_stop(struct rk3x_i2c *i2c, int error) +{ + unsigned int ctrl; + + i2c->processed = 0; + i2c->msg = NULL; + i2c->error = error; + + if (i2c->is_last_msg) { + /* Enable stop interrupt */ + i2c_writel(i2c, REG_INT_STOP, REG_IEN); + + i2c->state = STATE_STOP; + + ctrl = i2c_readl(i2c, REG_CON); + ctrl |= REG_CON_STOP; + i2c_writel(i2c, ctrl, REG_CON); + } else { + /* Signal rk3x_i2c_xfer to start the next message. */ + i2c->busy = false; + i2c->state = STATE_IDLE; + + /* + * The HW is actually not capable of REPEATED START. But we can + * get the intended effect by resetting its internal state + * and issuing an ordinary START. + */ + ctrl = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK; + i2c_writel(i2c, ctrl, REG_CON); + + /* signal that we are finished with the current msg */ + wake_up(&i2c->wait); + } +} + +/** + * rk3x_i2c_prepare_read - Setup a read according to i2c->msg + * @i2c: target controller data + */ +static void rk3x_i2c_prepare_read(struct rk3x_i2c *i2c) +{ + unsigned int len = i2c->msg->len - i2c->processed; + u32 con; + + con = i2c_readl(i2c, REG_CON); + + /* + * The hw can read up to 32 bytes at a time. If we need more than one + * chunk, send an ACK after the last byte of the current chunk. + */ + if (len > 32) { + len = 32; + con &= ~REG_CON_LASTACK; + } else { + con |= REG_CON_LASTACK; + } + + /* make sure we are in plain RX mode if we read a second chunk */ + if (i2c->processed != 0) { + con &= ~REG_CON_MOD_MASK; + con |= REG_CON_MOD(REG_CON_MOD_RX); + } + + i2c_writel(i2c, con, REG_CON); + i2c_writel(i2c, len, REG_MRXCNT); +} + +/** + * rk3x_i2c_fill_transmit_buf - Fill the transmit buffer with data from i2c->msg + * @i2c: target controller data + */ +static void rk3x_i2c_fill_transmit_buf(struct rk3x_i2c *i2c) +{ + unsigned int i, j; + u32 cnt = 0; + u32 val; + u8 byte; + + for (i = 0; i < 8; ++i) { + val = 0; + for (j = 0; j < 4; ++j) { + if ((i2c->processed == i2c->msg->len) && (cnt != 0)) + break; + + if (i2c->processed == 0 && cnt == 0) + byte = (i2c->addr & 0x7f) << 1; + else + byte = i2c->msg->buf[i2c->processed++]; + + val |= byte << (j * 8); + cnt++; + } + + i2c_writel(i2c, val, TXBUFFER_BASE + 4 * i); + + if (i2c->processed == i2c->msg->len) + break; + } + + i2c_writel(i2c, cnt, REG_MTXCNT); +} + + +/* IRQ handlers for individual states */ + +static void rk3x_i2c_handle_start(struct rk3x_i2c *i2c, unsigned int ipd) +{ + if (!(ipd & REG_INT_START)) { + rk3x_i2c_stop(i2c, -EIO); + dev_warn(i2c->dev, "unexpected irq in START: 0x%x\n", ipd); + rk3x_i2c_clean_ipd(i2c); + return; + } + + /* ack interrupt */ + i2c_writel(i2c, REG_INT_START, REG_IPD); + + /* disable start bit */ + i2c_writel(i2c, i2c_readl(i2c, REG_CON) & ~REG_CON_START, REG_CON); + + /* enable appropriate interrupts and transition */ + if (i2c->mode == REG_CON_MOD_TX) { + i2c_writel(i2c, REG_INT_MBTF | REG_INT_NAKRCV, REG_IEN); + i2c->state = STATE_WRITE; + rk3x_i2c_fill_transmit_buf(i2c); + } else { + /* in any other case, we are going to be reading. */ + i2c_writel(i2c, REG_INT_MBRF | REG_INT_NAKRCV, REG_IEN); + i2c->state = STATE_READ; + rk3x_i2c_prepare_read(i2c); + } +} + +static void rk3x_i2c_handle_write(struct rk3x_i2c *i2c, unsigned int ipd) +{ + if (!(ipd & REG_INT_MBTF)) { + rk3x_i2c_stop(i2c, -EIO); + dev_err(i2c->dev, "unexpected irq in WRITE: 0x%x\n", ipd); + rk3x_i2c_clean_ipd(i2c); + return; + } + + /* ack interrupt */ + i2c_writel(i2c, REG_INT_MBTF, REG_IPD); + + /* are we finished? */ + if (i2c->processed == i2c->msg->len) + rk3x_i2c_stop(i2c, i2c->error); + else + rk3x_i2c_fill_transmit_buf(i2c); +} + +static void rk3x_i2c_handle_read(struct rk3x_i2c *i2c, unsigned int ipd) +{ + unsigned int i; + unsigned int len = i2c->msg->len - i2c->processed; + u32 val; + u8 byte; + + /* we only care for MBRF here. */ + if (!(ipd & REG_INT_MBRF)) + return; + + /* ack interrupt (read also produces a spurious START flag, clear it too) */ + i2c_writel(i2c, REG_INT_MBRF | REG_INT_START, REG_IPD); + + /* Can only handle a maximum of 32 bytes at a time */ + if (len > 32) + len = 32; + + /* read the data from receive buffer */ + for (i = 0; i < len; ++i) { + if (i % 4 == 0) + val = i2c_readl(i2c, RXBUFFER_BASE + (i / 4) * 4); + + byte = (val >> ((i % 4) * 8)) & 0xff; + i2c->msg->buf[i2c->processed++] = byte; + } + + /* are we finished? */ + if (i2c->processed == i2c->msg->len) + rk3x_i2c_stop(i2c, i2c->error); + else + rk3x_i2c_prepare_read(i2c); +} + +static void rk3x_i2c_handle_stop(struct rk3x_i2c *i2c, unsigned int ipd) +{ + unsigned int con; + + if (!(ipd & REG_INT_STOP)) { + rk3x_i2c_stop(i2c, -EIO); + dev_err(i2c->dev, "unexpected irq in STOP: 0x%x\n", ipd); + rk3x_i2c_clean_ipd(i2c); + return; + } + + /* ack interrupt */ + i2c_writel(i2c, REG_INT_STOP, REG_IPD); + + /* disable STOP bit */ + con = i2c_readl(i2c, REG_CON); + con &= ~REG_CON_STOP; + i2c_writel(i2c, con, REG_CON); + + i2c->busy = false; + i2c->state = STATE_IDLE; + + /* signal rk3x_i2c_xfer that we are finished */ + wake_up(&i2c->wait); +} + +static irqreturn_t rk3x_i2c_irq(int irqno, void *dev_id) +{ + struct rk3x_i2c *i2c = dev_id; + unsigned int ipd; + + spin_lock(&i2c->lock); + + ipd = i2c_readl(i2c, REG_IPD); + if (i2c->state == STATE_IDLE) { + dev_warn(i2c->dev, "irq in STATE_IDLE, ipd = 0x%x\n", ipd); + rk3x_i2c_clean_ipd(i2c); + goto out; + } + + dev_dbg(i2c->dev, "IRQ: state %d, ipd: %x\n", i2c->state, ipd); + + /* Clean interrupt bits we don't care about */ + ipd &= ~(REG_INT_BRF | REG_INT_BTF); + + if (ipd & REG_INT_NAKRCV) { + /* + * We got a NACK in the last operation. Depending on whether + * IGNORE_NAK is set, we have to stop the operation and report + * an error. + */ + i2c_writel(i2c, REG_INT_NAKRCV, REG_IPD); + + ipd &= ~REG_INT_NAKRCV; + + if (!(i2c->msg->flags & I2C_M_IGNORE_NAK)) + rk3x_i2c_stop(i2c, -ENXIO); + } + + /* is there anything left to handle? */ + if ((ipd & REG_INT_ALL) == 0) + goto out; + + switch (i2c->state) { + case STATE_START: + rk3x_i2c_handle_start(i2c, ipd); + break; + case STATE_WRITE: + rk3x_i2c_handle_write(i2c, ipd); + break; + case STATE_READ: + rk3x_i2c_handle_read(i2c, ipd); + break; + case STATE_STOP: + rk3x_i2c_handle_stop(i2c, ipd); + break; + case STATE_IDLE: + break; + } + +out: + spin_unlock(&i2c->lock); + return IRQ_HANDLED; +} + +/** + * rk3x_i2c_get_spec - Get timing values of I2C specification + * @speed: Desired SCL frequency + * + * Return: Matched i2c_spec_values. + */ +static const struct i2c_spec_values *rk3x_i2c_get_spec(unsigned int speed) +{ + if (speed <= I2C_MAX_STANDARD_MODE_FREQ) + return &standard_mode_spec; + else if (speed <= I2C_MAX_FAST_MODE_FREQ) + return &fast_mode_spec; + else + return &fast_mode_plus_spec; +} + +/** + * rk3x_i2c_v0_calc_timings - Calculate divider values for desired SCL frequency + * @clk_rate: I2C input clock rate + * @t: Known I2C timing information + * @t_calc: Caculated rk3x private timings that would be written into regs + * + * Return: %0 on success, -%EINVAL if the goal SCL rate is too slow. In that case + * a best-effort divider value is returned in divs. If the target rate is + * too high, we silently use the highest possible rate. + */ +static int rk3x_i2c_v0_calc_timings(unsigned long clk_rate, + struct i2c_timings *t, + struct rk3x_i2c_calced_timings *t_calc) +{ + unsigned long min_low_ns, min_high_ns; + unsigned long max_low_ns, min_total_ns; + + unsigned long clk_rate_khz, scl_rate_khz; + + unsigned long min_low_div, min_high_div; + unsigned long max_low_div; + + unsigned long min_div_for_hold, min_total_div; + unsigned long extra_div, extra_low_div, ideal_low_div; + + unsigned long data_hold_buffer_ns = 50; + const struct i2c_spec_values *spec; + int ret = 0; + + /* Only support standard-mode and fast-mode */ + if (WARN_ON(t->bus_freq_hz > I2C_MAX_FAST_MODE_FREQ)) + t->bus_freq_hz = I2C_MAX_FAST_MODE_FREQ; + + /* prevent scl_rate_khz from becoming 0 */ + if (WARN_ON(t->bus_freq_hz < 1000)) + t->bus_freq_hz = 1000; + + /* + * min_low_ns: The minimum number of ns we need to hold low to + * meet I2C specification, should include fall time. + * min_high_ns: The minimum number of ns we need to hold high to + * meet I2C specification, should include rise time. + * max_low_ns: The maximum number of ns we can hold low to meet + * I2C specification. + * + * Note: max_low_ns should be (maximum data hold time * 2 - buffer) + * This is because the i2c host on Rockchip holds the data line + * for half the low time. + */ + spec = rk3x_i2c_get_spec(t->bus_freq_hz); + min_high_ns = t->scl_rise_ns + spec->min_high_ns; + + /* + * Timings for repeated start: + * - controller appears to drop SDA at .875x (7/8) programmed clk high. + * - controller appears to keep SCL high for 2x programmed clk high. + * + * We need to account for those rules in picking our "high" time so + * we meet tSU;STA and tHD;STA times. + */ + min_high_ns = max(min_high_ns, DIV_ROUND_UP( + (t->scl_rise_ns + spec->min_setup_start_ns) * 1000, 875)); + min_high_ns = max(min_high_ns, DIV_ROUND_UP( + (t->scl_rise_ns + spec->min_setup_start_ns + t->sda_fall_ns + + spec->min_high_ns), 2)); + + min_low_ns = t->scl_fall_ns + spec->min_low_ns; + max_low_ns = spec->max_data_hold_ns * 2 - data_hold_buffer_ns; + min_total_ns = min_low_ns + min_high_ns; + + /* Adjust to avoid overflow */ + clk_rate_khz = DIV_ROUND_UP(clk_rate, 1000); + scl_rate_khz = t->bus_freq_hz / 1000; + + /* + * We need the total div to be >= this number + * so we don't clock too fast. + */ + min_total_div = DIV_ROUND_UP(clk_rate_khz, scl_rate_khz * 8); + + /* These are the min dividers needed for min hold times. */ + min_low_div = DIV_ROUND_UP(clk_rate_khz * min_low_ns, 8 * 1000000); + min_high_div = DIV_ROUND_UP(clk_rate_khz * min_high_ns, 8 * 1000000); + min_div_for_hold = (min_low_div + min_high_div); + + /* + * This is the maximum divider so we don't go over the maximum. + * We don't round up here (we round down) since this is a maximum. + */ + max_low_div = clk_rate_khz * max_low_ns / (8 * 1000000); + + if (min_low_div > max_low_div) { + WARN_ONCE(true, + "Conflicting, min_low_div %lu, max_low_div %lu\n", + min_low_div, max_low_div); + max_low_div = min_low_div; + } + + if (min_div_for_hold > min_total_div) { + /* + * Time needed to meet hold requirements is important. + * Just use that. + */ + t_calc->div_low = min_low_div; + t_calc->div_high = min_high_div; + } else { + /* + * We've got to distribute some time among the low and high + * so we don't run too fast. + */ + extra_div = min_total_div - min_div_for_hold; + + /* + * We'll try to split things up perfectly evenly, + * biasing slightly towards having a higher div + * for low (spend more time low). + */ + ideal_low_div = DIV_ROUND_UP(clk_rate_khz * min_low_ns, + scl_rate_khz * 8 * min_total_ns); + + /* Don't allow it to go over the maximum */ + if (ideal_low_div > max_low_div) + ideal_low_div = max_low_div; + + /* + * Handle when the ideal low div is going to take up + * more than we have. + */ + if (ideal_low_div > min_low_div + extra_div) + ideal_low_div = min_low_div + extra_div; + + /* Give low the "ideal" and give high whatever extra is left */ + extra_low_div = ideal_low_div - min_low_div; + t_calc->div_low = ideal_low_div; + t_calc->div_high = min_high_div + (extra_div - extra_low_div); + } + + /* + * Adjust to the fact that the hardware has an implicit "+1". + * NOTE: Above calculations always produce div_low > 0 and div_high > 0. + */ + t_calc->div_low--; + t_calc->div_high--; + + /* Give the tuning value 0, that would not update con register */ + t_calc->tuning = 0; + /* Maximum divider supported by hw is 0xffff */ + if (t_calc->div_low > 0xffff) { + t_calc->div_low = 0xffff; + ret = -EINVAL; + } + + if (t_calc->div_high > 0xffff) { + t_calc->div_high = 0xffff; + ret = -EINVAL; + } + + return ret; +} + +/** + * rk3x_i2c_v1_calc_timings - Calculate timing values for desired SCL frequency + * @clk_rate: I2C input clock rate + * @t: Known I2C timing information + * @t_calc: Caculated rk3x private timings that would be written into regs + * + * Return: %0 on success, -%EINVAL if the goal SCL rate is too slow. In that case + * a best-effort divider value is returned in divs. If the target rate is + * too high, we silently use the highest possible rate. + * The following formulas are v1's method to calculate timings. + * + * l = divl + 1; + * h = divh + 1; + * s = sda_update_config + 1; + * u = start_setup_config + 1; + * p = stop_setup_config + 1; + * T = Tclk_i2c; + * + * tHigh = 8 * h * T; + * tLow = 8 * l * T; + * + * tHD;sda = (l * s + 1) * T; + * tSU;sda = [(8 - s) * l + 1] * T; + * tI2C = 8 * (l + h) * T; + * + * tSU;sta = (8h * u + 1) * T; + * tHD;sta = [8h * (u + 1) - 1] * T; + * tSU;sto = (8h * p + 1) * T; + */ +static int rk3x_i2c_v1_calc_timings(unsigned long clk_rate, + struct i2c_timings *t, + struct rk3x_i2c_calced_timings *t_calc) +{ + unsigned long min_low_ns, min_high_ns; + unsigned long min_setup_start_ns, min_setup_data_ns; + unsigned long min_setup_stop_ns, max_hold_data_ns; + + unsigned long clk_rate_khz, scl_rate_khz; + + unsigned long min_low_div, min_high_div; + + unsigned long min_div_for_hold, min_total_div; + unsigned long extra_div, extra_low_div; + unsigned long sda_update_cfg, stp_sta_cfg, stp_sto_cfg; + + const struct i2c_spec_values *spec; + int ret = 0; + + /* Support standard-mode, fast-mode and fast-mode plus */ + if (WARN_ON(t->bus_freq_hz > I2C_MAX_FAST_MODE_PLUS_FREQ)) + t->bus_freq_hz = I2C_MAX_FAST_MODE_PLUS_FREQ; + + /* prevent scl_rate_khz from becoming 0 */ + if (WARN_ON(t->bus_freq_hz < 1000)) + t->bus_freq_hz = 1000; + + /* + * min_low_ns: The minimum number of ns we need to hold low to + * meet I2C specification, should include fall time. + * min_high_ns: The minimum number of ns we need to hold high to + * meet I2C specification, should include rise time. + */ + spec = rk3x_i2c_get_spec(t->bus_freq_hz); + + /* calculate min-divh and min-divl */ + clk_rate_khz = DIV_ROUND_UP(clk_rate, 1000); + scl_rate_khz = t->bus_freq_hz / 1000; + min_total_div = DIV_ROUND_UP(clk_rate_khz, scl_rate_khz * 8); + + min_high_ns = t->scl_rise_ns + spec->min_high_ns; + min_high_div = DIV_ROUND_UP(clk_rate_khz * min_high_ns, 8 * 1000000); + + min_low_ns = t->scl_fall_ns + spec->min_low_ns; + min_low_div = DIV_ROUND_UP(clk_rate_khz * min_low_ns, 8 * 1000000); + + /* + * Final divh and divl must be greater than 0, otherwise the + * hardware would not output the i2c clk. + */ + min_high_div = (min_high_div < 1) ? 2 : min_high_div; + min_low_div = (min_low_div < 1) ? 2 : min_low_div; + + /* These are the min dividers needed for min hold times. */ + min_div_for_hold = (min_low_div + min_high_div); + + /* + * This is the maximum divider so we don't go over the maximum. + * We don't round up here (we round down) since this is a maximum. + */ + if (min_div_for_hold >= min_total_div) { + /* + * Time needed to meet hold requirements is important. + * Just use that. + */ + t_calc->div_low = min_low_div; + t_calc->div_high = min_high_div; + } else { + /* + * We've got to distribute some time among the low and high + * so we don't run too fast. + * We'll try to split things up by the scale of min_low_div and + * min_high_div, biasing slightly towards having a higher div + * for low (spend more time low). + */ + extra_div = min_total_div - min_div_for_hold; + extra_low_div = DIV_ROUND_UP(min_low_div * extra_div, + min_div_for_hold); + + t_calc->div_low = min_low_div + extra_low_div; + t_calc->div_high = min_high_div + (extra_div - extra_low_div); + } + + /* + * calculate sda data hold count by the rules, data_upd_st:3 + * is a appropriate value to reduce calculated times. + */ + for (sda_update_cfg = 3; sda_update_cfg > 0; sda_update_cfg--) { + max_hold_data_ns = DIV_ROUND_UP((sda_update_cfg + * (t_calc->div_low) + 1) + * 1000000, clk_rate_khz); + min_setup_data_ns = DIV_ROUND_UP(((8 - sda_update_cfg) + * (t_calc->div_low) + 1) + * 1000000, clk_rate_khz); + if ((max_hold_data_ns < spec->max_data_hold_ns) && + (min_setup_data_ns > spec->min_data_setup_ns)) + break; + } + + /* calculate setup start config */ + min_setup_start_ns = t->scl_rise_ns + spec->min_setup_start_ns; + stp_sta_cfg = DIV_ROUND_UP(clk_rate_khz * min_setup_start_ns + - 1000000, 8 * 1000000 * (t_calc->div_high)); + + /* calculate setup stop config */ + min_setup_stop_ns = t->scl_rise_ns + spec->min_setup_stop_ns; + stp_sto_cfg = DIV_ROUND_UP(clk_rate_khz * min_setup_stop_ns + - 1000000, 8 * 1000000 * (t_calc->div_high)); + + t_calc->tuning = REG_CON_SDA_CFG(--sda_update_cfg) | + REG_CON_STA_CFG(--stp_sta_cfg) | + REG_CON_STO_CFG(--stp_sto_cfg); + + t_calc->div_low--; + t_calc->div_high--; + + /* Maximum divider supported by hw is 0xffff */ + if (t_calc->div_low > 0xffff) { + t_calc->div_low = 0xffff; + ret = -EINVAL; + } + + if (t_calc->div_high > 0xffff) { + t_calc->div_high = 0xffff; + ret = -EINVAL; + } + + return ret; +} + +static void rk3x_i2c_adapt_div(struct rk3x_i2c *i2c, unsigned long clk_rate) +{ + struct i2c_timings *t = &i2c->t; + struct rk3x_i2c_calced_timings calc; + u64 t_low_ns, t_high_ns; + unsigned long flags; + u32 val; + int ret; + + ret = i2c->soc_data->calc_timings(clk_rate, t, &calc); + WARN_ONCE(ret != 0, "Could not reach SCL freq %u", t->bus_freq_hz); + + clk_enable(i2c->pclk); + + spin_lock_irqsave(&i2c->lock, flags); + val = i2c_readl(i2c, REG_CON); + val &= ~REG_CON_TUNING_MASK; + val |= calc.tuning; + i2c_writel(i2c, val, REG_CON); + i2c_writel(i2c, (calc.div_high << 16) | (calc.div_low & 0xffff), + REG_CLKDIV); + spin_unlock_irqrestore(&i2c->lock, flags); + + clk_disable(i2c->pclk); + + t_low_ns = div_u64(((u64)calc.div_low + 1) * 8 * 1000000000, clk_rate); + t_high_ns = div_u64(((u64)calc.div_high + 1) * 8 * 1000000000, + clk_rate); + dev_dbg(i2c->dev, + "CLK %lukhz, Req %uns, Act low %lluns high %lluns\n", + clk_rate / 1000, + 1000000000 / t->bus_freq_hz, + t_low_ns, t_high_ns); +} + +/** + * rk3x_i2c_clk_notifier_cb - Clock rate change callback + * @nb: Pointer to notifier block + * @event: Notification reason + * @data: Pointer to notification data object + * + * The callback checks whether a valid bus frequency can be generated after the + * change. If so, the change is acknowledged, otherwise the change is aborted. + * New dividers are written to the HW in the pre- or post change notification + * depending on the scaling direction. + * + * Code adapted from i2c-cadence.c. + * + * Return: NOTIFY_STOP if the rate change should be aborted, NOTIFY_OK + * to acknowledge the change, NOTIFY_DONE if the notification is + * considered irrelevant. + */ +static int rk3x_i2c_clk_notifier_cb(struct notifier_block *nb, unsigned long + event, void *data) +{ + struct clk_notifier_data *ndata = data; + struct rk3x_i2c *i2c = container_of(nb, struct rk3x_i2c, clk_rate_nb); + struct rk3x_i2c_calced_timings calc; + + switch (event) { + case PRE_RATE_CHANGE: + /* + * Try the calculation (but don't store the result) ahead of + * time to see if we need to block the clock change. Timings + * shouldn't actually take effect until rk3x_i2c_adapt_div(). + */ + if (i2c->soc_data->calc_timings(ndata->new_rate, &i2c->t, + &calc) != 0) + return NOTIFY_STOP; + + /* scale up */ + if (ndata->new_rate > ndata->old_rate) + rk3x_i2c_adapt_div(i2c, ndata->new_rate); + + return NOTIFY_OK; + case POST_RATE_CHANGE: + /* scale down */ + if (ndata->new_rate < ndata->old_rate) + rk3x_i2c_adapt_div(i2c, ndata->new_rate); + return NOTIFY_OK; + case ABORT_RATE_CHANGE: + /* scale up */ + if (ndata->new_rate > ndata->old_rate) + rk3x_i2c_adapt_div(i2c, ndata->old_rate); + return NOTIFY_OK; + default: + return NOTIFY_DONE; + } +} + +/** + * rk3x_i2c_setup - Setup I2C registers for an I2C operation specified by msgs, num. + * @i2c: target controller data + * @msgs: I2C msgs to process + * @num: Number of msgs + * + * Must be called with i2c->lock held. + * + * Return: Number of I2C msgs processed or negative in case of error + */ +static int rk3x_i2c_setup(struct rk3x_i2c *i2c, struct i2c_msg *msgs, int num) +{ + u32 addr = (msgs[0].addr & 0x7f) << 1; + int ret = 0; + + /* + * The I2C adapter can issue a small (len < 4) write packet before + * reading. This speeds up SMBus-style register reads. + * The MRXADDR/MRXRADDR hold the slave address and the slave register + * address in this case. + */ + + if (num >= 2 && msgs[0].len < 4 && + !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) { + u32 reg_addr = 0; + int i; + + dev_dbg(i2c->dev, "Combined write/read from addr 0x%x\n", + addr >> 1); + + /* Fill MRXRADDR with the register address(es) */ + for (i = 0; i < msgs[0].len; ++i) { + reg_addr |= msgs[0].buf[i] << (i * 8); + reg_addr |= REG_MRXADDR_VALID(i); + } + + /* msgs[0] is handled by hw. */ + i2c->msg = &msgs[1]; + + i2c->mode = REG_CON_MOD_REGISTER_TX; + + i2c_writel(i2c, addr | REG_MRXADDR_VALID(0), REG_MRXADDR); + i2c_writel(i2c, reg_addr, REG_MRXRADDR); + + ret = 2; + } else { + /* + * We'll have to do it the boring way and process the msgs + * one-by-one. + */ + + if (msgs[0].flags & I2C_M_RD) { + addr |= 1; /* set read bit */ + + /* + * We have to transmit the slave addr first. Use + * MOD_REGISTER_TX for that purpose. + */ + i2c->mode = REG_CON_MOD_REGISTER_TX; + i2c_writel(i2c, addr | REG_MRXADDR_VALID(0), + REG_MRXADDR); + i2c_writel(i2c, 0, REG_MRXRADDR); + } else { + i2c->mode = REG_CON_MOD_TX; + } + + i2c->msg = &msgs[0]; + + ret = 1; + } + + i2c->addr = msgs[0].addr; + i2c->busy = true; + i2c->state = STATE_START; + i2c->processed = 0; + i2c->error = 0; + + rk3x_i2c_clean_ipd(i2c); + + return ret; +} + +static int rk3x_i2c_wait_xfer_poll(struct rk3x_i2c *i2c) +{ + ktime_t timeout = ktime_add_ms(ktime_get(), WAIT_TIMEOUT); + + while (READ_ONCE(i2c->busy) && + ktime_compare(ktime_get(), timeout) < 0) { + udelay(5); + rk3x_i2c_irq(0, i2c); + } + + return !i2c->busy; +} + +static int rk3x_i2c_xfer_common(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num, bool polling) +{ + struct rk3x_i2c *i2c = (struct rk3x_i2c *)adap->algo_data; + unsigned long timeout, flags; + u32 val; + int ret = 0; + int i; + + spin_lock_irqsave(&i2c->lock, flags); + + clk_enable(i2c->clk); + clk_enable(i2c->pclk); + + i2c->is_last_msg = false; + + /* + * Process msgs. We can handle more than one message at once (see + * rk3x_i2c_setup()). + */ + for (i = 0; i < num; i += ret) { + ret = rk3x_i2c_setup(i2c, msgs + i, num - i); + + if (ret < 0) { + dev_err(i2c->dev, "rk3x_i2c_setup() failed\n"); + break; + } + + if (i + ret >= num) + i2c->is_last_msg = true; + + spin_unlock_irqrestore(&i2c->lock, flags); + + if (!polling) { + rk3x_i2c_start(i2c); + + timeout = wait_event_timeout(i2c->wait, !i2c->busy, + msecs_to_jiffies(WAIT_TIMEOUT)); + } else { + disable_irq(i2c->irq); + rk3x_i2c_start(i2c); + + timeout = rk3x_i2c_wait_xfer_poll(i2c); + + enable_irq(i2c->irq); + } + + spin_lock_irqsave(&i2c->lock, flags); + + if (timeout == 0) { + dev_err(i2c->dev, "timeout, ipd: 0x%02x, state: %d\n", + i2c_readl(i2c, REG_IPD), i2c->state); + + /* Force a STOP condition without interrupt */ + i2c_writel(i2c, 0, REG_IEN); + val = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK; + val |= REG_CON_EN | REG_CON_STOP; + i2c_writel(i2c, val, REG_CON); + + i2c->state = STATE_IDLE; + + ret = -ETIMEDOUT; + break; + } + + if (i2c->error) { + ret = i2c->error; + break; + } + } + + clk_disable(i2c->pclk); + clk_disable(i2c->clk); + + spin_unlock_irqrestore(&i2c->lock, flags); + + return ret < 0 ? ret : num; +} + +static int rk3x_i2c_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + return rk3x_i2c_xfer_common(adap, msgs, num, false); +} + +static int rk3x_i2c_xfer_polling(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + return rk3x_i2c_xfer_common(adap, msgs, num, true); +} + +static __maybe_unused int rk3x_i2c_resume(struct device *dev) +{ + struct rk3x_i2c *i2c = dev_get_drvdata(dev); + + rk3x_i2c_adapt_div(i2c, clk_get_rate(i2c->clk)); + + return 0; +} + +static u32 rk3x_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_PROTOCOL_MANGLING; +} + +static const struct i2c_algorithm rk3x_i2c_algorithm = { + .master_xfer = rk3x_i2c_xfer, + .master_xfer_atomic = rk3x_i2c_xfer_polling, + .functionality = rk3x_i2c_func, +}; + +static const struct rk3x_i2c_soc_data rv1108_soc_data = { + .grf_offset = -1, + .calc_timings = rk3x_i2c_v1_calc_timings, +}; + +static const struct rk3x_i2c_soc_data rv1126_soc_data = { + .grf_offset = 0x118, + .calc_timings = rk3x_i2c_v1_calc_timings, +}; + +static const struct rk3x_i2c_soc_data rk3066_soc_data = { + .grf_offset = 0x154, + .calc_timings = rk3x_i2c_v0_calc_timings, +}; + +static const struct rk3x_i2c_soc_data rk3188_soc_data = { + .grf_offset = 0x0a4, + .calc_timings = rk3x_i2c_v0_calc_timings, +}; + +static const struct rk3x_i2c_soc_data rk3228_soc_data = { + .grf_offset = -1, + .calc_timings = rk3x_i2c_v0_calc_timings, +}; + +static const struct rk3x_i2c_soc_data rk3288_soc_data = { + .grf_offset = -1, + .calc_timings = rk3x_i2c_v0_calc_timings, +}; + +static const struct rk3x_i2c_soc_data rk3399_soc_data = { + .grf_offset = -1, + .calc_timings = rk3x_i2c_v1_calc_timings, +}; + +static const struct of_device_id rk3x_i2c_match[] = { + { + .compatible = "rockchip,rv1108-i2c", + .data = &rv1108_soc_data + }, + { + .compatible = "rockchip,rv1126-i2c", + .data = &rv1126_soc_data + }, + { + .compatible = "rockchip,rk3066-i2c", + .data = &rk3066_soc_data + }, + { + .compatible = "rockchip,rk3188-i2c", + .data = &rk3188_soc_data + }, + { + .compatible = "rockchip,rk3228-i2c", + .data = &rk3228_soc_data + }, + { + .compatible = "rockchip,rk3288-i2c", + .data = &rk3288_soc_data + }, + { + .compatible = "rockchip,rk3399-i2c", + .data = &rk3399_soc_data + }, + {}, +}; +MODULE_DEVICE_TABLE(of, rk3x_i2c_match); + +static int rk3x_i2c_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + const struct of_device_id *match; + struct rk3x_i2c *i2c; + int ret = 0; + int bus_nr; + u32 value; + int irq; + unsigned long clk_rate; + + i2c = devm_kzalloc(&pdev->dev, sizeof(struct rk3x_i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + match = of_match_node(rk3x_i2c_match, np); + i2c->soc_data = match->data; + + /* use common interface to get I2C timing properties */ + i2c_parse_fw_timings(&pdev->dev, &i2c->t, true); + + strscpy(i2c->adap.name, "rk3x-i2c", sizeof(i2c->adap.name)); + i2c->adap.owner = THIS_MODULE; + i2c->adap.algo = &rk3x_i2c_algorithm; + i2c->adap.retries = 3; + i2c->adap.dev.of_node = np; + i2c->adap.algo_data = i2c; + i2c->adap.dev.parent = &pdev->dev; + + i2c->dev = &pdev->dev; + + spin_lock_init(&i2c->lock); + init_waitqueue_head(&i2c->wait); + + i2c->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c->regs)) + return PTR_ERR(i2c->regs); + + /* Try to set the I2C adapter number from dt */ + bus_nr = of_alias_get_id(np, "i2c"); + + /* + * Switch to new interface if the SoC also offers the old one. + * The control bit is located in the GRF register space. + */ + if (i2c->soc_data->grf_offset >= 0) { + struct regmap *grf; + + grf = syscon_regmap_lookup_by_phandle(np, "rockchip,grf"); + if (IS_ERR(grf)) { + dev_err(&pdev->dev, + "rk3x-i2c needs 'rockchip,grf' property\n"); + return PTR_ERR(grf); + } + + if (bus_nr < 0) { + dev_err(&pdev->dev, "rk3x-i2c needs i2cX alias"); + return -EINVAL; + } + + /* 27+i: write mask, 11+i: value */ + value = BIT(27 + bus_nr) | BIT(11 + bus_nr); + + ret = regmap_write(grf, i2c->soc_data->grf_offset, value); + if (ret != 0) { + dev_err(i2c->dev, "Could not write to GRF: %d\n", ret); + return ret; + } + } + + /* IRQ setup */ + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + ret = devm_request_irq(&pdev->dev, irq, rk3x_i2c_irq, + 0, dev_name(&pdev->dev), i2c); + if (ret < 0) { + dev_err(&pdev->dev, "cannot request IRQ\n"); + return ret; + } + + i2c->irq = irq; + + platform_set_drvdata(pdev, i2c); + + if (i2c->soc_data->calc_timings == rk3x_i2c_v0_calc_timings) { + /* Only one clock to use for bus clock and peripheral clock */ + i2c->clk = devm_clk_get(&pdev->dev, NULL); + i2c->pclk = i2c->clk; + } else { + i2c->clk = devm_clk_get(&pdev->dev, "i2c"); + i2c->pclk = devm_clk_get(&pdev->dev, "pclk"); + } + + if (IS_ERR(i2c->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(i2c->clk), + "Can't get bus clk\n"); + + if (IS_ERR(i2c->pclk)) + return dev_err_probe(&pdev->dev, PTR_ERR(i2c->pclk), + "Can't get periph clk\n"); + + ret = clk_prepare(i2c->clk); + if (ret < 0) { + dev_err(&pdev->dev, "Can't prepare bus clk: %d\n", ret); + return ret; + } + ret = clk_prepare(i2c->pclk); + if (ret < 0) { + dev_err(&pdev->dev, "Can't prepare periph clock: %d\n", ret); + goto err_clk; + } + + i2c->clk_rate_nb.notifier_call = rk3x_i2c_clk_notifier_cb; + ret = clk_notifier_register(i2c->clk, &i2c->clk_rate_nb); + if (ret != 0) { + dev_err(&pdev->dev, "Unable to register clock notifier\n"); + goto err_pclk; + } + + ret = clk_enable(i2c->clk); + if (ret < 0) { + dev_err(&pdev->dev, "Can't enable bus clk: %d\n", ret); + goto err_clk_notifier; + } + + clk_rate = clk_get_rate(i2c->clk); + rk3x_i2c_adapt_div(i2c, clk_rate); + clk_disable(i2c->clk); + + ret = i2c_add_adapter(&i2c->adap); + if (ret < 0) + goto err_clk_notifier; + + return 0; + +err_clk_notifier: + clk_notifier_unregister(i2c->clk, &i2c->clk_rate_nb); +err_pclk: + clk_unprepare(i2c->pclk); +err_clk: + clk_unprepare(i2c->clk); + return ret; +} + +static void rk3x_i2c_remove(struct platform_device *pdev) +{ + struct rk3x_i2c *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adap); + + clk_notifier_unregister(i2c->clk, &i2c->clk_rate_nb); + clk_unprepare(i2c->pclk); + clk_unprepare(i2c->clk); +} + +static SIMPLE_DEV_PM_OPS(rk3x_i2c_pm_ops, NULL, rk3x_i2c_resume); + +static struct platform_driver rk3x_i2c_driver = { + .probe = rk3x_i2c_probe, + .remove_new = rk3x_i2c_remove, + .driver = { + .name = "rk3x-i2c", + .of_match_table = rk3x_i2c_match, + .pm = &rk3x_i2c_pm_ops, + }, +}; + +module_platform_driver(rk3x_i2c_driver); + +MODULE_DESCRIPTION("Rockchip RK3xxx I2C Bus driver"); +MODULE_AUTHOR("Max Schwarz <max.schwarz@online.de>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-robotfuzz-osif.c b/drivers/i2c/busses/i2c-robotfuzz-osif.c new file mode 100644 index 000000000..66dfa211e --- /dev/null +++ b/drivers/i2c/busses/i2c-robotfuzz-osif.c @@ -0,0 +1,196 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for RobotFuzz OSIF + * + * Copyright (c) 2013 Andrew Lunn <andrew@lunn.ch> + * Copyright (c) 2007 Barry Carter <Barry.Carter@robotfuzz.com> + * + * Based on the i2c-tiny-usb by + * + * Copyright (C) 2006 Til Harbaum (Till@Harbaum.org) + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/slab.h> +#include <linux/usb.h> + +#define OSIFI2C_READ 20 +#define OSIFI2C_WRITE 21 +#define OSIFI2C_STOP 22 +#define OSIFI2C_STATUS 23 +#define OSIFI2C_SET_BIT_RATE 24 + +#define STATUS_ADDRESS_ACK 0 +#define STATUS_ADDRESS_NAK 2 + +struct osif_priv { + struct usb_device *usb_dev; + struct usb_interface *interface; + struct i2c_adapter adapter; + unsigned char status; +}; + +static int osif_usb_read(struct i2c_adapter *adapter, int cmd, + int value, int index, void *data, int len) +{ + struct osif_priv *priv = adapter->algo_data; + + return usb_control_msg(priv->usb_dev, usb_rcvctrlpipe(priv->usb_dev, 0), + cmd, USB_TYPE_VENDOR | USB_RECIP_INTERFACE | + USB_DIR_IN, value, index, data, len, 2000); +} + +static int osif_usb_write(struct i2c_adapter *adapter, int cmd, + int value, int index, void *data, int len) +{ + + struct osif_priv *priv = adapter->algo_data; + + return usb_control_msg(priv->usb_dev, usb_sndctrlpipe(priv->usb_dev, 0), + cmd, USB_TYPE_VENDOR | USB_RECIP_INTERFACE, + value, index, data, len, 2000); +} + +static int osif_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, + int num) +{ + struct osif_priv *priv = adapter->algo_data; + struct i2c_msg *pmsg; + int ret; + int i; + + for (i = 0; i < num; i++) { + pmsg = &msgs[i]; + + if (pmsg->flags & I2C_M_RD) { + ret = osif_usb_read(adapter, OSIFI2C_READ, + pmsg->flags, pmsg->addr, + pmsg->buf, pmsg->len); + if (ret != pmsg->len) { + dev_err(&adapter->dev, "failure reading data\n"); + return -EREMOTEIO; + } + } else { + ret = osif_usb_write(adapter, OSIFI2C_WRITE, + pmsg->flags, pmsg->addr, + pmsg->buf, pmsg->len); + if (ret != pmsg->len) { + dev_err(&adapter->dev, "failure writing data\n"); + return -EREMOTEIO; + } + } + + ret = osif_usb_write(adapter, OSIFI2C_STOP, 0, 0, NULL, 0); + if (ret) { + dev_err(&adapter->dev, "failure sending STOP\n"); + return -EREMOTEIO; + } + + /* read status */ + ret = osif_usb_read(adapter, OSIFI2C_STATUS, 0, 0, + &priv->status, 1); + if (ret != 1) { + dev_err(&adapter->dev, "failure reading status\n"); + return -EREMOTEIO; + } + + if (priv->status != STATUS_ADDRESS_ACK) { + dev_dbg(&adapter->dev, "status = %d\n", priv->status); + return -EREMOTEIO; + } + } + + return i; +} + +static u32 osif_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm osif_algorithm = { + .master_xfer = osif_xfer, + .functionality = osif_func, +}; + +#define USB_OSIF_VENDOR_ID 0x1964 +#define USB_OSIF_PRODUCT_ID 0x0001 + +static const struct usb_device_id osif_table[] = { + { USB_DEVICE(USB_OSIF_VENDOR_ID, USB_OSIF_PRODUCT_ID) }, + { } +}; +MODULE_DEVICE_TABLE(usb, osif_table); + +static int osif_probe(struct usb_interface *interface, + const struct usb_device_id *id) +{ + int ret; + struct osif_priv *priv; + u16 version; + + priv = devm_kzalloc(&interface->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->usb_dev = usb_get_dev(interface_to_usbdev(interface)); + priv->interface = interface; + + usb_set_intfdata(interface, priv); + + priv->adapter.owner = THIS_MODULE; + priv->adapter.class = I2C_CLASS_HWMON; + priv->adapter.algo = &osif_algorithm; + priv->adapter.algo_data = priv; + snprintf(priv->adapter.name, sizeof(priv->adapter.name), + "OSIF at bus %03d device %03d", + priv->usb_dev->bus->busnum, priv->usb_dev->devnum); + + /* + * Set bus frequency. The frequency is: + * 120,000,000 / ( 16 + 2 * div * 4^prescale). + * Using dev = 52, prescale = 0 give 100KHz */ + ret = osif_usb_write(&priv->adapter, OSIFI2C_SET_BIT_RATE, 52, 0, + NULL, 0); + if (ret) { + dev_err(&interface->dev, "failure sending bit rate"); + usb_put_dev(priv->usb_dev); + return ret; + } + + i2c_add_adapter(&(priv->adapter)); + + version = le16_to_cpu(priv->usb_dev->descriptor.bcdDevice); + dev_info(&interface->dev, + "version %x.%02x found at bus %03d address %03d", + version >> 8, version & 0xff, + priv->usb_dev->bus->busnum, priv->usb_dev->devnum); + + return 0; +} + +static void osif_disconnect(struct usb_interface *interface) +{ + struct osif_priv *priv = usb_get_intfdata(interface); + + i2c_del_adapter(&(priv->adapter)); + usb_set_intfdata(interface, NULL); + usb_put_dev(priv->usb_dev); +} + +static struct usb_driver osif_driver = { + .name = "RobotFuzz Open Source InterFace, OSIF", + .probe = osif_probe, + .disconnect = osif_disconnect, + .id_table = osif_table, +}; + +module_usb_driver(osif_driver); + +MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>"); +MODULE_AUTHOR("Barry Carter <barry.carter@robotfuzz.com>"); +MODULE_DESCRIPTION("RobotFuzz OSIF driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-rzv2m.c b/drivers/i2c/busses/i2c-rzv2m.c new file mode 100644 index 000000000..b0bfc96b9 --- /dev/null +++ b/drivers/i2c/busses/i2c-rzv2m.c @@ -0,0 +1,545 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for the Renesas RZ/V2M I2C unit + * + * Copyright (C) 2016-2022 Renesas Electronics Corporation + */ + +#include <linux/bits.h> +#include <linux/clk.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/i2c.h> +#include <linux/jiffies.h> +#include <linux/kernel.h> +#include <linux/math64.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/reset.h> + +/* Register offsets */ +#define IICB0DAT 0x00 /* Data Register */ +#define IICB0CTL0 0x08 /* Control Register 0 */ +#define IICB0TRG 0x0C /* Trigger Register */ +#define IICB0STR0 0x10 /* Status Register 0 */ +#define IICB0CTL1 0x20 /* Control Register 1 */ +#define IICB0WL 0x24 /* Low Level Width Setting Reg */ +#define IICB0WH 0x28 /* How Level Width Setting Reg */ + +/* IICB0CTL0 */ +#define IICB0IICE BIT(7) /* I2C Enable */ +#define IICB0SLWT BIT(1) /* Interrupt Request Timing */ +#define IICB0SLAC BIT(0) /* Acknowledge */ + +/* IICB0TRG */ +#define IICB0WRET BIT(2) /* Quit Wait Trigger */ +#define IICB0STT BIT(1) /* Create Start Condition Trigger */ +#define IICB0SPT BIT(0) /* Create Stop Condition Trigger */ + +/* IICB0STR0 */ +#define IICB0SSAC BIT(8) /* Ack Flag */ +#define IICB0SSBS BIT(6) /* Bus Flag */ +#define IICB0SSSP BIT(4) /* Stop Condition Flag */ + +/* IICB0CTL1 */ +#define IICB0MDSC BIT(7) /* Bus Mode */ +#define IICB0SLSE BIT(1) /* Start condition output */ + +struct rzv2m_i2c_priv { + void __iomem *base; + struct i2c_adapter adap; + struct clk *clk; + int bus_mode; + struct completion msg_tia_done; + u32 iicb0wl; + u32 iicb0wh; +}; + +enum bcr_index { + RZV2M_I2C_100K = 0, + RZV2M_I2C_400K, +}; + +struct bitrate_config { + unsigned int percent_low; + unsigned int min_hold_time_ns; +}; + +static const struct bitrate_config bitrate_configs[] = { + [RZV2M_I2C_100K] = { 47, 3450 }, + [RZV2M_I2C_400K] = { 52, 900 }, +}; + +static inline void bit_setl(void __iomem *addr, u32 val) +{ + writel(readl(addr) | val, addr); +} + +static inline void bit_clrl(void __iomem *addr, u32 val) +{ + writel(readl(addr) & ~val, addr); +} + +static irqreturn_t rzv2m_i2c_tia_irq_handler(int this_irq, void *dev_id) +{ + struct rzv2m_i2c_priv *priv = dev_id; + + complete(&priv->msg_tia_done); + + return IRQ_HANDLED; +} + +/* Calculate IICB0WL and IICB0WH */ +static int rzv2m_i2c_clock_calculate(struct device *dev, + struct rzv2m_i2c_priv *priv) +{ + const struct bitrate_config *config; + unsigned int hold_time_ns; + unsigned int total_pclks; + unsigned int trf_pclks; + unsigned long pclk_hz; + struct i2c_timings t; + u32 trf_ns; + + i2c_parse_fw_timings(dev, &t, true); + + pclk_hz = clk_get_rate(priv->clk); + total_pclks = pclk_hz / t.bus_freq_hz; + + trf_ns = t.scl_rise_ns + t.scl_fall_ns; + trf_pclks = mul_u64_u32_div(pclk_hz, trf_ns, NSEC_PER_SEC); + + /* Config setting */ + switch (t.bus_freq_hz) { + case I2C_MAX_FAST_MODE_FREQ: + priv->bus_mode = RZV2M_I2C_400K; + break; + case I2C_MAX_STANDARD_MODE_FREQ: + priv->bus_mode = RZV2M_I2C_100K; + break; + default: + dev_err(dev, "transfer speed is invalid\n"); + return -EINVAL; + } + config = &bitrate_configs[priv->bus_mode]; + + /* IICB0WL = (percent_low / Transfer clock) x PCLK */ + priv->iicb0wl = total_pclks * config->percent_low / 100; + if (priv->iicb0wl > (BIT(10) - 1)) + return -EINVAL; + + /* IICB0WH = ((percent_high / Transfer clock) x PCLK) - (tR + tF) */ + priv->iicb0wh = total_pclks - priv->iicb0wl - trf_pclks; + if (priv->iicb0wh > (BIT(10) - 1)) + return -EINVAL; + + /* + * Data hold time must be less than 0.9us in fast mode and + * 3.45us in standard mode. + * Data hold time = IICB0WL[9:2] / PCLK + */ + hold_time_ns = div64_ul((u64)(priv->iicb0wl >> 2) * NSEC_PER_SEC, pclk_hz); + if (hold_time_ns > config->min_hold_time_ns) { + dev_err(dev, "data hold time %dns is over %dns\n", + hold_time_ns, config->min_hold_time_ns); + return -EINVAL; + } + + return 0; +} + +static void rzv2m_i2c_init(struct rzv2m_i2c_priv *priv) +{ + u32 i2c_ctl0; + u32 i2c_ctl1; + + /* i2c disable */ + writel(0, priv->base + IICB0CTL0); + + /* IICB0CTL1 setting */ + i2c_ctl1 = IICB0SLSE; + if (priv->bus_mode == RZV2M_I2C_400K) + i2c_ctl1 |= IICB0MDSC; + writel(i2c_ctl1, priv->base + IICB0CTL1); + + /* IICB0WL IICB0WH setting */ + writel(priv->iicb0wl, priv->base + IICB0WL); + writel(priv->iicb0wh, priv->base + IICB0WH); + + /* i2c enable after setting */ + i2c_ctl0 = IICB0SLWT | IICB0SLAC | IICB0IICE; + writel(i2c_ctl0, priv->base + IICB0CTL0); +} + +static int rzv2m_i2c_write_with_ack(struct rzv2m_i2c_priv *priv, u32 data) +{ + unsigned long time_left; + + reinit_completion(&priv->msg_tia_done); + + writel(data, priv->base + IICB0DAT); + + time_left = wait_for_completion_timeout(&priv->msg_tia_done, + priv->adap.timeout); + if (!time_left) + return -ETIMEDOUT; + + /* Confirm ACK */ + if ((readl(priv->base + IICB0STR0) & IICB0SSAC) != IICB0SSAC) + return -ENXIO; + + return 0; +} + +static int rzv2m_i2c_read_with_ack(struct rzv2m_i2c_priv *priv, u8 *data, + bool last) +{ + unsigned long time_left; + u32 data_tmp; + + reinit_completion(&priv->msg_tia_done); + + /* Interrupt request timing : 8th clock */ + bit_clrl(priv->base + IICB0CTL0, IICB0SLWT); + + /* Exit the wait state */ + writel(IICB0WRET, priv->base + IICB0TRG); + + /* Wait for transaction */ + time_left = wait_for_completion_timeout(&priv->msg_tia_done, + priv->adap.timeout); + if (!time_left) + return -ETIMEDOUT; + + if (last) { + /* Disable ACK */ + bit_clrl(priv->base + IICB0CTL0, IICB0SLAC); + + /* Read data*/ + data_tmp = readl(priv->base + IICB0DAT); + + /* Interrupt request timing : 9th clock */ + bit_setl(priv->base + IICB0CTL0, IICB0SLWT); + + /* Exit the wait state */ + writel(IICB0WRET, priv->base + IICB0TRG); + + /* Wait for transaction */ + time_left = wait_for_completion_timeout(&priv->msg_tia_done, + priv->adap.timeout); + if (!time_left) + return -ETIMEDOUT; + + /* Enable ACK */ + bit_setl(priv->base + IICB0CTL0, IICB0SLAC); + } else { + /* Read data */ + data_tmp = readl(priv->base + IICB0DAT); + } + + *data = data_tmp; + + return 0; +} + +static int rzv2m_i2c_send(struct rzv2m_i2c_priv *priv, struct i2c_msg *msg, + unsigned int *count) +{ + unsigned int i; + int ret; + + for (i = 0; i < msg->len; i++) { + ret = rzv2m_i2c_write_with_ack(priv, msg->buf[i]); + if (ret < 0) + return ret; + } + *count = i; + + return 0; +} + +static int rzv2m_i2c_receive(struct rzv2m_i2c_priv *priv, struct i2c_msg *msg, + unsigned int *count) +{ + unsigned int i; + int ret; + + for (i = 0; i < msg->len; i++) { + ret = rzv2m_i2c_read_with_ack(priv, &msg->buf[i], + (msg->len - 1) == i); + if (ret < 0) + return ret; + } + *count = i; + + return 0; +} + +static int rzv2m_i2c_send_address(struct rzv2m_i2c_priv *priv, + struct i2c_msg *msg) +{ + u32 addr; + int ret; + + if (msg->flags & I2C_M_TEN) { + /* + * 10-bit address + * addr_1: 5'b11110 | addr[9:8] | (R/nW) + * addr_2: addr[7:0] + */ + addr = 0xf0 | ((msg->addr & GENMASK(9, 8)) >> 7); + addr |= !!(msg->flags & I2C_M_RD); + /* Send 1st address(extend code) */ + ret = rzv2m_i2c_write_with_ack(priv, addr); + if (ret) + return ret; + + /* Send 2nd address */ + ret = rzv2m_i2c_write_with_ack(priv, msg->addr & 0xff); + } else { + /* 7-bit address */ + addr = i2c_8bit_addr_from_msg(msg); + ret = rzv2m_i2c_write_with_ack(priv, addr); + } + + return ret; +} + +static int rzv2m_i2c_stop_condition(struct rzv2m_i2c_priv *priv) +{ + u32 value; + + /* Send stop condition */ + writel(IICB0SPT, priv->base + IICB0TRG); + return readl_poll_timeout(priv->base + IICB0STR0, + value, value & IICB0SSSP, + 100, jiffies_to_usecs(priv->adap.timeout)); +} + +static int rzv2m_i2c_master_xfer_msg(struct rzv2m_i2c_priv *priv, + struct i2c_msg *msg, int stop) +{ + unsigned int count = 0; + int ret, read = !!(msg->flags & I2C_M_RD); + + /* Send start condition */ + writel(IICB0STT, priv->base + IICB0TRG); + + ret = rzv2m_i2c_send_address(priv, msg); + if (!ret) { + if (read) + ret = rzv2m_i2c_receive(priv, msg, &count); + else + ret = rzv2m_i2c_send(priv, msg, &count); + + if (!ret && stop) + ret = rzv2m_i2c_stop_condition(priv); + } + + if (ret == -ENXIO) + rzv2m_i2c_stop_condition(priv); + else if (ret < 0) + rzv2m_i2c_init(priv); + else + ret = count; + + return ret; +} + +static int rzv2m_i2c_master_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct rzv2m_i2c_priv *priv = i2c_get_adapdata(adap); + struct device *dev = priv->adap.dev.parent; + unsigned int i; + int ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) + return ret; + + if (readl(priv->base + IICB0STR0) & IICB0SSBS) { + ret = -EAGAIN; + goto out; + } + + /* I2C main transfer */ + for (i = 0; i < num; i++) { + ret = rzv2m_i2c_master_xfer_msg(priv, &msgs[i], i == (num - 1)); + if (ret < 0) + goto out; + } + ret = num; + +out: + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + + return ret; +} + +static u32 rzv2m_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | + I2C_FUNC_10BIT_ADDR; +} + +static int rzv2m_i2c_disable(struct device *dev, struct rzv2m_i2c_priv *priv) +{ + int ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) + return ret; + + bit_clrl(priv->base + IICB0CTL0, IICB0IICE); + pm_runtime_put(dev); + + return 0; +} + +static const struct i2c_adapter_quirks rzv2m_i2c_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN, +}; + +static struct i2c_algorithm rzv2m_i2c_algo = { + .master_xfer = rzv2m_i2c_master_xfer, + .functionality = rzv2m_i2c_func, +}; + +static int rzv2m_i2c_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct rzv2m_i2c_priv *priv; + struct reset_control *rstc; + struct i2c_adapter *adap; + struct resource *res; + int irq, ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(priv->base)) + return PTR_ERR(priv->base); + + priv->clk = devm_clk_get(dev, NULL); + if (IS_ERR(priv->clk)) + return dev_err_probe(dev, PTR_ERR(priv->clk), "Can't get clock\n"); + + rstc = devm_reset_control_get_shared(dev, NULL); + if (IS_ERR(rstc)) + return dev_err_probe(dev, PTR_ERR(rstc), "Missing reset ctrl\n"); + /* + * The reset also affects other HW that is not under the control + * of Linux. Therefore, all we can do is deassert the reset. + */ + reset_control_deassert(rstc); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + ret = devm_request_irq(dev, irq, rzv2m_i2c_tia_irq_handler, 0, + dev_name(dev), priv); + if (ret < 0) + return dev_err_probe(dev, ret, "Unable to request irq %d\n", irq); + + adap = &priv->adap; + adap->nr = pdev->id; + adap->algo = &rzv2m_i2c_algo; + adap->quirks = &rzv2m_i2c_quirks; + adap->dev.parent = dev; + adap->owner = THIS_MODULE; + device_set_node(&adap->dev, dev_fwnode(dev)); + i2c_set_adapdata(adap, priv); + strscpy(adap->name, pdev->name, sizeof(adap->name)); + init_completion(&priv->msg_tia_done); + + ret = rzv2m_i2c_clock_calculate(dev, priv); + if (ret < 0) + return ret; + + pm_runtime_enable(dev); + + pm_runtime_get_sync(dev); + rzv2m_i2c_init(priv); + pm_runtime_put(dev); + + platform_set_drvdata(pdev, priv); + + ret = i2c_add_numbered_adapter(adap); + if (ret < 0) { + rzv2m_i2c_disable(dev, priv); + pm_runtime_disable(dev); + } + + return ret; +} + +static void rzv2m_i2c_remove(struct platform_device *pdev) +{ + struct rzv2m_i2c_priv *priv = platform_get_drvdata(pdev); + struct device *dev = priv->adap.dev.parent; + + i2c_del_adapter(&priv->adap); + rzv2m_i2c_disable(dev, priv); + pm_runtime_disable(dev); +} + +static int rzv2m_i2c_suspend(struct device *dev) +{ + struct rzv2m_i2c_priv *priv = dev_get_drvdata(dev); + + return rzv2m_i2c_disable(dev, priv); +} + +static int rzv2m_i2c_resume(struct device *dev) +{ + struct rzv2m_i2c_priv *priv = dev_get_drvdata(dev); + int ret; + + ret = rzv2m_i2c_clock_calculate(dev, priv); + if (ret < 0) + return ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) + return ret; + + rzv2m_i2c_init(priv); + pm_runtime_put(dev); + + return 0; +} + +static const struct of_device_id rzv2m_i2c_ids[] = { + { .compatible = "renesas,rzv2m-i2c" }, + { } +}; +MODULE_DEVICE_TABLE(of, rzv2m_i2c_ids); + +static const struct dev_pm_ops rzv2m_i2c_pm_ops = { + SYSTEM_SLEEP_PM_OPS(rzv2m_i2c_suspend, rzv2m_i2c_resume) +}; + +static struct platform_driver rzv2m_i2c_driver = { + .driver = { + .name = "rzv2m-i2c", + .of_match_table = rzv2m_i2c_ids, + .pm = pm_sleep_ptr(&rzv2m_i2c_pm_ops), + }, + .probe = rzv2m_i2c_probe, + .remove_new = rzv2m_i2c_remove, +}; +module_platform_driver(rzv2m_i2c_driver); + +MODULE_DESCRIPTION("RZ/V2M I2C bus driver"); +MODULE_AUTHOR("Renesas Electronics Corporation"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c new file mode 100644 index 000000000..c324cb3c9 --- /dev/null +++ b/drivers/i2c/busses/i2c-s3c2410.c @@ -0,0 +1,1186 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* linux/drivers/i2c/busses/i2c-s3c2410.c + * + * Copyright (C) 2004,2005,2009 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * + * S3C2410 I2C Controller +*/ + +#include <linux/kernel.h> +#include <linux/module.h> + +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/time.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/clk.h> +#include <linux/cpufreq.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/gpio/consumer.h> +#include <linux/pinctrl/consumer.h> +#include <linux/mfd/syscon.h> +#include <linux/regmap.h> + +#include <asm/irq.h> + +#include <linux/platform_data/i2c-s3c2410.h> + +/* see s3c2410x user guide, v1.1, section 9 (p447) for more info */ + +#define S3C2410_IICCON 0x00 +#define S3C2410_IICSTAT 0x04 +#define S3C2410_IICADD 0x08 +#define S3C2410_IICDS 0x0C +#define S3C2440_IICLC 0x10 + +#define S3C2410_IICCON_ACKEN (1 << 7) +#define S3C2410_IICCON_TXDIV_16 (0 << 6) +#define S3C2410_IICCON_TXDIV_512 (1 << 6) +#define S3C2410_IICCON_IRQEN (1 << 5) +#define S3C2410_IICCON_IRQPEND (1 << 4) +#define S3C2410_IICCON_SCALE(x) ((x) & 0xf) +#define S3C2410_IICCON_SCALEMASK (0xf) + +#define S3C2410_IICSTAT_MASTER_RX (2 << 6) +#define S3C2410_IICSTAT_MASTER_TX (3 << 6) +#define S3C2410_IICSTAT_SLAVE_RX (0 << 6) +#define S3C2410_IICSTAT_SLAVE_TX (1 << 6) +#define S3C2410_IICSTAT_MODEMASK (3 << 6) + +#define S3C2410_IICSTAT_START (1 << 5) +#define S3C2410_IICSTAT_BUSBUSY (1 << 5) +#define S3C2410_IICSTAT_TXRXEN (1 << 4) +#define S3C2410_IICSTAT_ARBITR (1 << 3) +#define S3C2410_IICSTAT_ASSLAVE (1 << 2) +#define S3C2410_IICSTAT_ADDR0 (1 << 1) +#define S3C2410_IICSTAT_LASTBIT (1 << 0) + +#define S3C2410_IICLC_SDA_DELAY0 (0 << 0) +#define S3C2410_IICLC_SDA_DELAY5 (1 << 0) +#define S3C2410_IICLC_SDA_DELAY10 (2 << 0) +#define S3C2410_IICLC_SDA_DELAY15 (3 << 0) +#define S3C2410_IICLC_SDA_DELAY_MASK (3 << 0) + +#define S3C2410_IICLC_FILTER_ON (1 << 2) + +/* Treat S3C2410 as baseline hardware, anything else is supported via quirks */ +#define QUIRK_S3C2440 (1 << 0) +#define QUIRK_HDMIPHY (1 << 1) +#define QUIRK_NO_GPIO (1 << 2) +#define QUIRK_POLL (1 << 3) + +/* Max time to wait for bus to become idle after a xfer (in us) */ +#define S3C2410_IDLE_TIMEOUT 5000 + +/* Exynos5 Sysreg offset */ +#define EXYNOS5_SYS_I2C_CFG 0x0234 + +/* i2c controller state */ +enum s3c24xx_i2c_state { + STATE_IDLE, + STATE_START, + STATE_READ, + STATE_WRITE, + STATE_STOP +}; + +struct s3c24xx_i2c { + wait_queue_head_t wait; + kernel_ulong_t quirks; + + struct i2c_msg *msg; + unsigned int msg_num; + unsigned int msg_idx; + unsigned int msg_ptr; + + unsigned int tx_setup; + unsigned int irq; + + enum s3c24xx_i2c_state state; + unsigned long clkrate; + + void __iomem *regs; + struct clk *clk; + struct device *dev; + struct i2c_adapter adap; + + struct s3c2410_platform_i2c *pdata; + struct gpio_desc *gpios[2]; + struct pinctrl *pctrl; + struct regmap *sysreg; + unsigned int sys_i2c_cfg; +}; + +static const struct platform_device_id s3c24xx_driver_ids[] = { + { + .name = "s3c2410-i2c", + .driver_data = 0, + }, { + .name = "s3c2440-i2c", + .driver_data = QUIRK_S3C2440, + }, { + .name = "s3c2440-hdmiphy-i2c", + .driver_data = QUIRK_S3C2440 | QUIRK_HDMIPHY | QUIRK_NO_GPIO, + }, { }, +}; +MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids); + +static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat); + +#ifdef CONFIG_OF +static const struct of_device_id s3c24xx_i2c_match[] = { + { .compatible = "samsung,s3c2410-i2c", .data = (void *)0 }, + { .compatible = "samsung,s3c2440-i2c", .data = (void *)QUIRK_S3C2440 }, + { .compatible = "samsung,s3c2440-hdmiphy-i2c", + .data = (void *)(QUIRK_S3C2440 | QUIRK_HDMIPHY | QUIRK_NO_GPIO) }, + { .compatible = "samsung,exynos5-sata-phy-i2c", + .data = (void *)(QUIRK_S3C2440 | QUIRK_POLL | QUIRK_NO_GPIO) }, + {}, +}; +MODULE_DEVICE_TABLE(of, s3c24xx_i2c_match); +#endif + +/* + * Get controller type either from device tree or platform device variant. + */ +static inline kernel_ulong_t s3c24xx_get_device_quirks(struct platform_device *pdev) +{ + if (pdev->dev.of_node) + return (kernel_ulong_t)of_device_get_match_data(&pdev->dev); + + return platform_get_device_id(pdev)->driver_data; +} + +/* + * Complete the message and wake up the caller, using the given return code, + * or zero to mean ok. + */ +static inline void s3c24xx_i2c_master_complete(struct s3c24xx_i2c *i2c, int ret) +{ + dev_dbg(i2c->dev, "master_complete %d\n", ret); + + i2c->msg_ptr = 0; + i2c->msg = NULL; + i2c->msg_idx++; + i2c->msg_num = 0; + if (ret) + i2c->msg_idx = ret; + + if (!(i2c->quirks & QUIRK_POLL)) + wake_up(&i2c->wait); +} + +static inline void s3c24xx_i2c_disable_ack(struct s3c24xx_i2c *i2c) +{ + unsigned long tmp; + + tmp = readl(i2c->regs + S3C2410_IICCON); + writel(tmp & ~S3C2410_IICCON_ACKEN, i2c->regs + S3C2410_IICCON); +} + +static inline void s3c24xx_i2c_enable_ack(struct s3c24xx_i2c *i2c) +{ + unsigned long tmp; + + tmp = readl(i2c->regs + S3C2410_IICCON); + writel(tmp | S3C2410_IICCON_ACKEN, i2c->regs + S3C2410_IICCON); +} + +/* irq enable/disable functions */ +static inline void s3c24xx_i2c_disable_irq(struct s3c24xx_i2c *i2c) +{ + unsigned long tmp; + + tmp = readl(i2c->regs + S3C2410_IICCON); + writel(tmp & ~S3C2410_IICCON_IRQEN, i2c->regs + S3C2410_IICCON); +} + +static inline void s3c24xx_i2c_enable_irq(struct s3c24xx_i2c *i2c) +{ + unsigned long tmp; + + tmp = readl(i2c->regs + S3C2410_IICCON); + writel(tmp | S3C2410_IICCON_IRQEN, i2c->regs + S3C2410_IICCON); +} + +static bool is_ack(struct s3c24xx_i2c *i2c) +{ + int tries; + + for (tries = 50; tries; --tries) { + unsigned long tmp = readl(i2c->regs + S3C2410_IICCON); + + if (!(tmp & S3C2410_IICCON_ACKEN)) { + /* + * Wait a bit for the bus to stabilize, + * delay estimated experimentally. + */ + usleep_range(100, 200); + return true; + } + if (tmp & S3C2410_IICCON_IRQPEND) { + if (!(readl(i2c->regs + S3C2410_IICSTAT) + & S3C2410_IICSTAT_LASTBIT)) + return true; + } + usleep_range(1000, 2000); + } + dev_err(i2c->dev, "ack was not received\n"); + return false; +} + +/* + * put the start of a message onto the bus + */ +static void s3c24xx_i2c_message_start(struct s3c24xx_i2c *i2c, + struct i2c_msg *msg) +{ + unsigned int addr = (msg->addr & 0x7f) << 1; + unsigned long stat; + unsigned long iiccon; + + stat = 0; + stat |= S3C2410_IICSTAT_TXRXEN; + + if (msg->flags & I2C_M_RD) { + stat |= S3C2410_IICSTAT_MASTER_RX; + addr |= 1; + } else + stat |= S3C2410_IICSTAT_MASTER_TX; + + if (msg->flags & I2C_M_REV_DIR_ADDR) + addr ^= 1; + + /* todo - check for whether ack wanted or not */ + s3c24xx_i2c_enable_ack(i2c); + + iiccon = readl(i2c->regs + S3C2410_IICCON); + writel(stat, i2c->regs + S3C2410_IICSTAT); + + dev_dbg(i2c->dev, "START: %08lx to IICSTAT, %02x to DS\n", stat, addr); + writeb(addr, i2c->regs + S3C2410_IICDS); + + /* + * delay here to ensure the data byte has gotten onto the bus + * before the transaction is started + */ + ndelay(i2c->tx_setup); + + dev_dbg(i2c->dev, "iiccon, %08lx\n", iiccon); + writel(iiccon, i2c->regs + S3C2410_IICCON); + + stat |= S3C2410_IICSTAT_START; + writel(stat, i2c->regs + S3C2410_IICSTAT); +} + +static inline void s3c24xx_i2c_stop(struct s3c24xx_i2c *i2c, int ret) +{ + unsigned long iicstat = readl(i2c->regs + S3C2410_IICSTAT); + + dev_dbg(i2c->dev, "STOP\n"); + + /* + * The datasheet says that the STOP sequence should be: + * 1) I2CSTAT.5 = 0 - Clear BUSY (or 'generate STOP') + * 2) I2CCON.4 = 0 - Clear IRQPEND + * 3) Wait until the stop condition takes effect. + * 4*) I2CSTAT.4 = 0 - Clear TXRXEN + * + * Where, step "4*" is only for buses with the "HDMIPHY" quirk. + * + * However, after much experimentation, it appears that: + * a) normal buses automatically clear BUSY and transition from + * Master->Slave when they complete generating a STOP condition. + * Therefore, step (3) can be done in doxfer() by polling I2CCON.4 + * after starting the STOP generation here. + * b) HDMIPHY bus does neither, so there is no way to do step 3. + * There is no indication when this bus has finished generating + * STOP. + * + * In fact, we have found that as soon as the IRQPEND bit is cleared in + * step 2, the HDMIPHY bus generates the STOP condition, and then + * immediately starts transferring another data byte, even though the + * bus is supposedly stopped. This is presumably because the bus is + * still in "Master" mode, and its BUSY bit is still set. + * + * To avoid these extra post-STOP transactions on HDMI phy devices, we + * just disable Serial Output on the bus (I2CSTAT.4 = 0) directly, + * instead of first generating a proper STOP condition. This should + * float SDA & SCK terminating the transfer. Subsequent transfers + * start with a proper START condition, and proceed normally. + * + * The HDMIPHY bus is an internal bus that always has exactly two + * devices, the host as Master and the HDMIPHY device as the slave. + * Skipping the STOP condition has been tested on this bus and works. + */ + if (i2c->quirks & QUIRK_HDMIPHY) { + /* Stop driving the I2C pins */ + iicstat &= ~S3C2410_IICSTAT_TXRXEN; + } else { + /* stop the transfer */ + iicstat &= ~S3C2410_IICSTAT_START; + } + writel(iicstat, i2c->regs + S3C2410_IICSTAT); + + i2c->state = STATE_STOP; + + s3c24xx_i2c_master_complete(i2c, ret); + s3c24xx_i2c_disable_irq(i2c); +} + +/* + * helper functions to determine the current state in the set of + * messages we are sending + */ + +/* + * returns TRUE if the current message is the last in the set + */ +static inline int is_lastmsg(struct s3c24xx_i2c *i2c) +{ + return i2c->msg_idx >= (i2c->msg_num - 1); +} + +/* + * returns TRUE if we this is the last byte in the current message + */ +static inline int is_msglast(struct s3c24xx_i2c *i2c) +{ + /* + * msg->len is always 1 for the first byte of smbus block read. + * Actual length will be read from slave. More bytes will be + * read according to the length then. + */ + if (i2c->msg->flags & I2C_M_RECV_LEN && i2c->msg->len == 1) + return 0; + + return i2c->msg_ptr == i2c->msg->len-1; +} + +/* + * returns TRUE if we reached the end of the current message + */ +static inline int is_msgend(struct s3c24xx_i2c *i2c) +{ + return i2c->msg_ptr >= i2c->msg->len; +} + +/* + * process an interrupt and work out what to do + */ +static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat) +{ + unsigned long tmp; + unsigned char byte; + int ret = 0; + + switch (i2c->state) { + + case STATE_IDLE: + dev_err(i2c->dev, "%s: called in STATE_IDLE\n", __func__); + goto out; + + case STATE_STOP: + dev_err(i2c->dev, "%s: called in STATE_STOP\n", __func__); + s3c24xx_i2c_disable_irq(i2c); + goto out_ack; + + case STATE_START: + /* + * last thing we did was send a start condition on the + * bus, or started a new i2c message + */ + if (iicstat & S3C2410_IICSTAT_LASTBIT && + !(i2c->msg->flags & I2C_M_IGNORE_NAK)) { + /* ack was not received... */ + dev_dbg(i2c->dev, "ack was not received\n"); + s3c24xx_i2c_stop(i2c, -ENXIO); + goto out_ack; + } + + if (i2c->msg->flags & I2C_M_RD) + i2c->state = STATE_READ; + else + i2c->state = STATE_WRITE; + + /* + * Terminate the transfer if there is nothing to do + * as this is used by the i2c probe to find devices. + */ + if (is_lastmsg(i2c) && i2c->msg->len == 0) { + s3c24xx_i2c_stop(i2c, 0); + goto out_ack; + } + + if (i2c->state == STATE_READ) + goto prepare_read; + + /* + * fall through to the write state, as we will need to + * send a byte as well + */ + fallthrough; + case STATE_WRITE: + /* + * we are writing data to the device... check for the + * end of the message, and if so, work out what to do + */ + if (!(i2c->msg->flags & I2C_M_IGNORE_NAK)) { + if (iicstat & S3C2410_IICSTAT_LASTBIT) { + dev_dbg(i2c->dev, "WRITE: No Ack\n"); + + s3c24xx_i2c_stop(i2c, -ECONNREFUSED); + goto out_ack; + } + } + + retry_write: + + if (!is_msgend(i2c)) { + byte = i2c->msg->buf[i2c->msg_ptr++]; + writeb(byte, i2c->regs + S3C2410_IICDS); + + /* + * delay after writing the byte to allow the + * data setup time on the bus, as writing the + * data to the register causes the first bit + * to appear on SDA, and SCL will change as + * soon as the interrupt is acknowledged + */ + ndelay(i2c->tx_setup); + + } else if (!is_lastmsg(i2c)) { + /* we need to go to the next i2c message */ + + dev_dbg(i2c->dev, "WRITE: Next Message\n"); + + i2c->msg_ptr = 0; + i2c->msg_idx++; + i2c->msg++; + + /* check to see if we need to do another message */ + if (i2c->msg->flags & I2C_M_NOSTART) { + + if (i2c->msg->flags & I2C_M_RD) { + /* + * cannot do this, the controller + * forces us to send a new START + * when we change direction + */ + dev_dbg(i2c->dev, + "missing START before write->read\n"); + s3c24xx_i2c_stop(i2c, -EINVAL); + break; + } + + goto retry_write; + } else { + /* send the new start */ + s3c24xx_i2c_message_start(i2c, i2c->msg); + i2c->state = STATE_START; + } + + } else { + /* send stop */ + s3c24xx_i2c_stop(i2c, 0); + } + break; + + case STATE_READ: + /* + * we have a byte of data in the data register, do + * something with it, and then work out whether we are + * going to do any more read/write + */ + byte = readb(i2c->regs + S3C2410_IICDS); + i2c->msg->buf[i2c->msg_ptr++] = byte; + + /* Add actual length to read for smbus block read */ + if (i2c->msg->flags & I2C_M_RECV_LEN && i2c->msg->len == 1) + i2c->msg->len += byte; + prepare_read: + if (is_msglast(i2c)) { + /* last byte of buffer */ + + if (is_lastmsg(i2c)) + s3c24xx_i2c_disable_ack(i2c); + + } else if (is_msgend(i2c)) { + /* + * ok, we've read the entire buffer, see if there + * is anything else we need to do + */ + if (is_lastmsg(i2c)) { + /* last message, send stop and complete */ + dev_dbg(i2c->dev, "READ: Send Stop\n"); + + s3c24xx_i2c_stop(i2c, 0); + } else { + /* go to the next transfer */ + dev_dbg(i2c->dev, "READ: Next Transfer\n"); + + i2c->msg_ptr = 0; + i2c->msg_idx++; + i2c->msg++; + } + } + + break; + } + + /* acknowlegde the IRQ and get back on with the work */ + + out_ack: + tmp = readl(i2c->regs + S3C2410_IICCON); + tmp &= ~S3C2410_IICCON_IRQPEND; + writel(tmp, i2c->regs + S3C2410_IICCON); + out: + return ret; +} + +/* + * top level IRQ servicing routine + */ +static irqreturn_t s3c24xx_i2c_irq(int irqno, void *dev_id) +{ + struct s3c24xx_i2c *i2c = dev_id; + unsigned long status; + unsigned long tmp; + + status = readl(i2c->regs + S3C2410_IICSTAT); + + if (status & S3C2410_IICSTAT_ARBITR) { + /* deal with arbitration loss */ + dev_err(i2c->dev, "deal with arbitration loss\n"); + } + + if (i2c->state == STATE_IDLE) { + dev_dbg(i2c->dev, "IRQ: error i2c->state == IDLE\n"); + + tmp = readl(i2c->regs + S3C2410_IICCON); + tmp &= ~S3C2410_IICCON_IRQPEND; + writel(tmp, i2c->regs + S3C2410_IICCON); + goto out; + } + + /* + * pretty much this leaves us with the fact that we've + * transmitted or received whatever byte we last sent + */ + i2c_s3c_irq_nextbyte(i2c, status); + + out: + return IRQ_HANDLED; +} + +/* + * Disable the bus so that we won't get any interrupts from now on, or try + * to drive any lines. This is the default state when we don't have + * anything to send/receive. + * + * If there is an event on the bus, or we have a pre-existing event at + * kernel boot time, we may not notice the event and the I2C controller + * will lock the bus with the I2C clock line low indefinitely. + */ +static inline void s3c24xx_i2c_disable_bus(struct s3c24xx_i2c *i2c) +{ + unsigned long tmp; + + /* Stop driving the I2C pins */ + tmp = readl(i2c->regs + S3C2410_IICSTAT); + tmp &= ~S3C2410_IICSTAT_TXRXEN; + writel(tmp, i2c->regs + S3C2410_IICSTAT); + + /* We don't expect any interrupts now, and don't want send acks */ + tmp = readl(i2c->regs + S3C2410_IICCON); + tmp &= ~(S3C2410_IICCON_IRQEN | S3C2410_IICCON_IRQPEND | + S3C2410_IICCON_ACKEN); + writel(tmp, i2c->regs + S3C2410_IICCON); +} + + +/* + * get the i2c bus for a master transaction + */ +static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c) +{ + unsigned long iicstat; + int timeout = 400; + + while (timeout-- > 0) { + iicstat = readl(i2c->regs + S3C2410_IICSTAT); + + if (!(iicstat & S3C2410_IICSTAT_BUSBUSY)) + return 0; + + msleep(1); + } + + return -ETIMEDOUT; +} + +/* + * wait for the i2c bus to become idle. + */ +static void s3c24xx_i2c_wait_idle(struct s3c24xx_i2c *i2c) +{ + unsigned long iicstat; + ktime_t start, now; + unsigned long delay; + int spins; + + /* ensure the stop has been through the bus */ + + dev_dbg(i2c->dev, "waiting for bus idle\n"); + + start = now = ktime_get(); + + /* + * Most of the time, the bus is already idle within a few usec of the + * end of a transaction. However, really slow i2c devices can stretch + * the clock, delaying STOP generation. + * + * On slower SoCs this typically happens within a very small number of + * instructions so busy wait briefly to avoid scheduling overhead. + */ + spins = 3; + iicstat = readl(i2c->regs + S3C2410_IICSTAT); + while ((iicstat & S3C2410_IICSTAT_START) && --spins) { + cpu_relax(); + iicstat = readl(i2c->regs + S3C2410_IICSTAT); + } + + /* + * If we do get an appreciable delay as a compromise between idle + * detection latency for the normal, fast case, and system load in the + * slow device case, use an exponential back off in the polling loop, + * up to 1/10th of the total timeout, then continue to poll at a + * constant rate up to the timeout. + */ + delay = 1; + while ((iicstat & S3C2410_IICSTAT_START) && + ktime_us_delta(now, start) < S3C2410_IDLE_TIMEOUT) { + usleep_range(delay, 2 * delay); + if (delay < S3C2410_IDLE_TIMEOUT / 10) + delay <<= 1; + now = ktime_get(); + iicstat = readl(i2c->regs + S3C2410_IICSTAT); + } + + if (iicstat & S3C2410_IICSTAT_START) + dev_warn(i2c->dev, "timeout waiting for bus idle\n"); +} + +/* + * this starts an i2c transfer + */ +static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, + struct i2c_msg *msgs, int num) +{ + unsigned long timeout = 0; + int ret; + + ret = s3c24xx_i2c_set_master(i2c); + if (ret != 0) { + dev_err(i2c->dev, "cannot get bus (error %d)\n", ret); + ret = -EAGAIN; + goto out; + } + + i2c->msg = msgs; + i2c->msg_num = num; + i2c->msg_ptr = 0; + i2c->msg_idx = 0; + i2c->state = STATE_START; + + s3c24xx_i2c_enable_irq(i2c); + s3c24xx_i2c_message_start(i2c, msgs); + + if (i2c->quirks & QUIRK_POLL) { + while ((i2c->msg_num != 0) && is_ack(i2c)) { + unsigned long stat = readl(i2c->regs + S3C2410_IICSTAT); + + i2c_s3c_irq_nextbyte(i2c, stat); + + stat = readl(i2c->regs + S3C2410_IICSTAT); + if (stat & S3C2410_IICSTAT_ARBITR) + dev_err(i2c->dev, "deal with arbitration loss\n"); + } + } else { + timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5); + } + + ret = i2c->msg_idx; + + /* + * Having these next two as dev_err() makes life very + * noisy when doing an i2cdetect + */ + if (timeout == 0) + dev_dbg(i2c->dev, "timeout\n"); + else if (ret != num) + dev_dbg(i2c->dev, "incomplete xfer (%d)\n", ret); + + /* For QUIRK_HDMIPHY, bus is already disabled */ + if (i2c->quirks & QUIRK_HDMIPHY) + goto out; + + s3c24xx_i2c_wait_idle(i2c); + + s3c24xx_i2c_disable_bus(i2c); + + out: + i2c->state = STATE_IDLE; + + return ret; +} + +/* + * first port of call from the i2c bus code when an message needs + * transferring across the i2c bus. + */ +static int s3c24xx_i2c_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct s3c24xx_i2c *i2c = (struct s3c24xx_i2c *)adap->algo_data; + int retry; + int ret; + + ret = clk_enable(i2c->clk); + if (ret) + return ret; + + for (retry = 0; retry < adap->retries; retry++) { + + ret = s3c24xx_i2c_doxfer(i2c, msgs, num); + + if (ret != -EAGAIN) { + clk_disable(i2c->clk); + return ret; + } + + dev_dbg(i2c->dev, "Retrying transmission (%d)\n", retry); + + udelay(100); + } + + clk_disable(i2c->clk); + return -EREMOTEIO; +} + +/* declare our i2c functionality */ +static u32 s3c24xx_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL_ALL | I2C_FUNC_NOSTART | + I2C_FUNC_PROTOCOL_MANGLING; +} + +/* i2c bus registration info */ +static const struct i2c_algorithm s3c24xx_i2c_algorithm = { + .master_xfer = s3c24xx_i2c_xfer, + .functionality = s3c24xx_i2c_func, +}; + +/* + * return the divisor settings for a given frequency + */ +static int s3c24xx_i2c_calcdivisor(unsigned long clkin, unsigned int wanted, + unsigned int *div1, unsigned int *divs) +{ + unsigned int calc_divs = clkin / wanted; + unsigned int calc_div1; + + if (calc_divs > (16*16)) + calc_div1 = 512; + else + calc_div1 = 16; + + calc_divs += calc_div1-1; + calc_divs /= calc_div1; + + if (calc_divs == 0) + calc_divs = 1; + if (calc_divs > 17) + calc_divs = 17; + + *divs = calc_divs; + *div1 = calc_div1; + + return clkin / (calc_divs * calc_div1); +} + +/* + * work out a divisor for the user requested frequency setting, + * either by the requested frequency, or scanning the acceptable + * range of frequencies until something is found + */ +static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got) +{ + struct s3c2410_platform_i2c *pdata = i2c->pdata; + unsigned long clkin = clk_get_rate(i2c->clk); + unsigned int divs, div1; + unsigned long target_frequency; + u32 iiccon; + int freq; + + i2c->clkrate = clkin; + clkin /= 1000; /* clkin now in KHz */ + + dev_dbg(i2c->dev, "pdata desired frequency %lu\n", pdata->frequency); + + target_frequency = pdata->frequency ?: I2C_MAX_STANDARD_MODE_FREQ; + + target_frequency /= 1000; /* Target frequency now in KHz */ + + freq = s3c24xx_i2c_calcdivisor(clkin, target_frequency, &div1, &divs); + + if (freq > target_frequency) { + dev_err(i2c->dev, + "Unable to achieve desired frequency %luKHz." \ + " Lowest achievable %dKHz\n", target_frequency, freq); + return -EINVAL; + } + + *got = freq; + + iiccon = readl(i2c->regs + S3C2410_IICCON); + iiccon &= ~(S3C2410_IICCON_SCALEMASK | S3C2410_IICCON_TXDIV_512); + iiccon |= (divs-1); + + if (div1 == 512) + iiccon |= S3C2410_IICCON_TXDIV_512; + + if (i2c->quirks & QUIRK_POLL) + iiccon |= S3C2410_IICCON_SCALE(2); + + writel(iiccon, i2c->regs + S3C2410_IICCON); + + if (i2c->quirks & QUIRK_S3C2440) { + unsigned long sda_delay; + + if (pdata->sda_delay) { + sda_delay = clkin * pdata->sda_delay; + sda_delay = DIV_ROUND_UP(sda_delay, 1000000); + sda_delay = DIV_ROUND_UP(sda_delay, 5); + if (sda_delay > 3) + sda_delay = 3; + sda_delay |= S3C2410_IICLC_FILTER_ON; + } else + sda_delay = 0; + + dev_dbg(i2c->dev, "IICLC=%08lx\n", sda_delay); + writel(sda_delay, i2c->regs + S3C2440_IICLC); + } + + return 0; +} + +#ifdef CONFIG_OF +static int s3c24xx_i2c_parse_dt_gpio(struct s3c24xx_i2c *i2c) +{ + int i; + + if (i2c->quirks & QUIRK_NO_GPIO) + return 0; + + for (i = 0; i < 2; i++) { + i2c->gpios[i] = devm_gpiod_get_index(i2c->dev, NULL, + i, GPIOD_ASIS); + if (IS_ERR(i2c->gpios[i])) { + dev_err(i2c->dev, "i2c gpio invalid at index %d\n", i); + return -EINVAL; + } + } + return 0; +} + +#else +static int s3c24xx_i2c_parse_dt_gpio(struct s3c24xx_i2c *i2c) +{ + return 0; +} +#endif + +/* + * initialise the controller, set the IO lines and frequency + */ +static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c) +{ + struct s3c2410_platform_i2c *pdata; + unsigned int freq; + + /* get the plafrom data */ + + pdata = i2c->pdata; + + /* write slave address */ + + writeb(pdata->slave_addr, i2c->regs + S3C2410_IICADD); + + dev_info(i2c->dev, "slave address 0x%02x\n", pdata->slave_addr); + + writel(0, i2c->regs + S3C2410_IICCON); + writel(0, i2c->regs + S3C2410_IICSTAT); + + /* we need to work out the divisors for the clock... */ + + if (s3c24xx_i2c_clockrate(i2c, &freq) != 0) { + dev_err(i2c->dev, "cannot meet bus frequency required\n"); + return -EINVAL; + } + + /* todo - check that the i2c lines aren't being dragged anywhere */ + + dev_info(i2c->dev, "bus frequency set to %d KHz\n", freq); + dev_dbg(i2c->dev, "S3C2410_IICCON=0x%02x\n", + readl(i2c->regs + S3C2410_IICCON)); + + return 0; +} + +#ifdef CONFIG_OF +/* + * Parse the device tree node and retreive the platform data. + */ +static void +s3c24xx_i2c_parse_dt(struct device_node *np, struct s3c24xx_i2c *i2c) +{ + struct s3c2410_platform_i2c *pdata = i2c->pdata; + int id; + + if (!np) + return; + + pdata->bus_num = -1; /* i2c bus number is dynamically assigned */ + of_property_read_u32(np, "samsung,i2c-sda-delay", &pdata->sda_delay); + of_property_read_u32(np, "samsung,i2c-slave-addr", &pdata->slave_addr); + of_property_read_u32(np, "samsung,i2c-max-bus-freq", + (u32 *)&pdata->frequency); + /* + * Exynos5's legacy i2c controller and new high speed i2c + * controller have muxed interrupt sources. By default the + * interrupts for 4-channel HS-I2C controller are enabled. + * If nodes for first four channels of legacy i2c controller + * are available then re-configure the interrupts via the + * system register. + */ + id = of_alias_get_id(np, "i2c"); + i2c->sysreg = syscon_regmap_lookup_by_phandle(np, + "samsung,sysreg-phandle"); + if (IS_ERR(i2c->sysreg)) + return; + + regmap_update_bits(i2c->sysreg, EXYNOS5_SYS_I2C_CFG, BIT(id), 0); +} +#else +static void +s3c24xx_i2c_parse_dt(struct device_node *np, struct s3c24xx_i2c *i2c) { } +#endif + +static int s3c24xx_i2c_probe(struct platform_device *pdev) +{ + struct s3c24xx_i2c *i2c; + struct s3c2410_platform_i2c *pdata = NULL; + struct resource *res; + int ret; + + if (!pdev->dev.of_node) { + pdata = dev_get_platdata(&pdev->dev); + if (!pdata) { + dev_err(&pdev->dev, "no platform data\n"); + return -EINVAL; + } + } + + i2c = devm_kzalloc(&pdev->dev, sizeof(struct s3c24xx_i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + if (!i2c->pdata) + return -ENOMEM; + + i2c->quirks = s3c24xx_get_device_quirks(pdev); + i2c->sysreg = ERR_PTR(-ENOENT); + if (pdata) + memcpy(i2c->pdata, pdata, sizeof(*pdata)); + else + s3c24xx_i2c_parse_dt(pdev->dev.of_node, i2c); + + strscpy(i2c->adap.name, "s3c2410-i2c", sizeof(i2c->adap.name)); + i2c->adap.owner = THIS_MODULE; + i2c->adap.algo = &s3c24xx_i2c_algorithm; + i2c->adap.retries = 2; + i2c->adap.class = I2C_CLASS_DEPRECATED; + i2c->tx_setup = 50; + + init_waitqueue_head(&i2c->wait); + + /* find the clock and enable it */ + i2c->dev = &pdev->dev; + i2c->clk = devm_clk_get(&pdev->dev, "i2c"); + if (IS_ERR(i2c->clk)) { + dev_err(&pdev->dev, "cannot get clock\n"); + return -ENOENT; + } + + dev_dbg(&pdev->dev, "clock source %p\n", i2c->clk); + + /* map the registers */ + i2c->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(i2c->regs)) + return PTR_ERR(i2c->regs); + + dev_dbg(&pdev->dev, "registers %p (%p)\n", + i2c->regs, res); + + /* setup info block for the i2c core */ + i2c->adap.algo_data = i2c; + i2c->adap.dev.parent = &pdev->dev; + i2c->pctrl = devm_pinctrl_get_select_default(i2c->dev); + + /* inititalise the i2c gpio lines */ + if (i2c->pdata->cfg_gpio) + i2c->pdata->cfg_gpio(to_platform_device(i2c->dev)); + else if (IS_ERR(i2c->pctrl) && s3c24xx_i2c_parse_dt_gpio(i2c)) + return -EINVAL; + + /* initialise the i2c controller */ + ret = clk_prepare_enable(i2c->clk); + if (ret) { + dev_err(&pdev->dev, "I2C clock enable failed\n"); + return ret; + } + + ret = s3c24xx_i2c_init(i2c); + clk_disable(i2c->clk); + if (ret != 0) { + dev_err(&pdev->dev, "I2C controller init failed\n"); + clk_unprepare(i2c->clk); + return ret; + } + + /* + * find the IRQ for this unit (note, this relies on the init call to + * ensure no current IRQs pending + */ + if (!(i2c->quirks & QUIRK_POLL)) { + i2c->irq = ret = platform_get_irq(pdev, 0); + if (ret < 0) { + clk_unprepare(i2c->clk); + return ret; + } + + ret = devm_request_irq(&pdev->dev, i2c->irq, s3c24xx_i2c_irq, + 0, dev_name(&pdev->dev), i2c); + if (ret != 0) { + dev_err(&pdev->dev, "cannot claim IRQ %d\n", i2c->irq); + clk_unprepare(i2c->clk); + return ret; + } + } + + /* + * Note, previous versions of the driver used i2c_add_adapter() + * to add the bus at any number. We now pass the bus number via + * the platform data, so if unset it will now default to always + * being bus 0. + */ + i2c->adap.nr = i2c->pdata->bus_num; + i2c->adap.dev.of_node = pdev->dev.of_node; + + platform_set_drvdata(pdev, i2c); + + pm_runtime_enable(&pdev->dev); + + ret = i2c_add_numbered_adapter(&i2c->adap); + if (ret < 0) { + pm_runtime_disable(&pdev->dev); + clk_unprepare(i2c->clk); + return ret; + } + + dev_info(&pdev->dev, "%s: S3C I2C adapter\n", dev_name(&i2c->adap.dev)); + return 0; +} + +static void s3c24xx_i2c_remove(struct platform_device *pdev) +{ + struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev); + + clk_unprepare(i2c->clk); + + pm_runtime_disable(&pdev->dev); + + i2c_del_adapter(&i2c->adap); +} + +static int s3c24xx_i2c_suspend_noirq(struct device *dev) +{ + struct s3c24xx_i2c *i2c = dev_get_drvdata(dev); + + i2c_mark_adapter_suspended(&i2c->adap); + + if (!IS_ERR(i2c->sysreg)) + regmap_read(i2c->sysreg, EXYNOS5_SYS_I2C_CFG, &i2c->sys_i2c_cfg); + + return 0; +} + +static int s3c24xx_i2c_resume_noirq(struct device *dev) +{ + struct s3c24xx_i2c *i2c = dev_get_drvdata(dev); + int ret; + + if (!IS_ERR(i2c->sysreg)) + regmap_write(i2c->sysreg, EXYNOS5_SYS_I2C_CFG, i2c->sys_i2c_cfg); + + ret = clk_enable(i2c->clk); + if (ret) + return ret; + s3c24xx_i2c_init(i2c); + clk_disable(i2c->clk); + i2c_mark_adapter_resumed(&i2c->adap); + + return 0; +} + +static const struct dev_pm_ops s3c24xx_i2c_dev_pm_ops = { + NOIRQ_SYSTEM_SLEEP_PM_OPS(s3c24xx_i2c_suspend_noirq, + s3c24xx_i2c_resume_noirq) +}; + +static struct platform_driver s3c24xx_i2c_driver = { + .probe = s3c24xx_i2c_probe, + .remove_new = s3c24xx_i2c_remove, + .id_table = s3c24xx_driver_ids, + .driver = { + .name = "s3c-i2c", + .pm = pm_sleep_ptr(&s3c24xx_i2c_dev_pm_ops), + .of_match_table = of_match_ptr(s3c24xx_i2c_match), + }, +}; + +static int __init i2c_adap_s3c_init(void) +{ + return platform_driver_register(&s3c24xx_i2c_driver); +} +subsys_initcall(i2c_adap_s3c_init); + +static void __exit i2c_adap_s3c_exit(void) +{ + platform_driver_unregister(&s3c24xx_i2c_driver); +} +module_exit(i2c_adap_s3c_exit); + +MODULE_DESCRIPTION("S3C24XX I2C Bus driver"); +MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-scmi.c b/drivers/i2c/busses/i2c-scmi.c new file mode 100644 index 000000000..421735acf --- /dev/null +++ b/drivers/i2c/busses/i2c-scmi.c @@ -0,0 +1,424 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * SMBus driver for ACPI SMBus CMI + * + * Copyright (C) 2009 Crane Cai <crane.cai@amd.com> + */ + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/stddef.h> +#include <linux/i2c.h> +#include <linux/acpi.h> + +struct smbus_methods_t { + char *mt_info; + char *mt_sbr; + char *mt_sbw; +}; + +struct acpi_smbus_cmi { + acpi_handle handle; + struct i2c_adapter adapter; + u8 cap_info:1; + u8 cap_read:1; + u8 cap_write:1; + const struct smbus_methods_t *methods; +}; + +static const struct smbus_methods_t smbus_methods = { + .mt_info = "_SBI", + .mt_sbr = "_SBR", + .mt_sbw = "_SBW", +}; + +/* Some IBM BIOSes omit the leading underscore */ +static const struct smbus_methods_t ibm_smbus_methods = { + .mt_info = "SBI_", + .mt_sbr = "SBR_", + .mt_sbw = "SBW_", +}; + +static const struct acpi_device_id acpi_smbus_cmi_ids[] = { + {"SMBUS01", (kernel_ulong_t)&smbus_methods}, + {ACPI_SMBUS_IBM_HID, (kernel_ulong_t)&ibm_smbus_methods}, + {ACPI_SMBUS_MS_HID, (kernel_ulong_t)&smbus_methods}, + {"", 0} +}; +MODULE_DEVICE_TABLE(acpi, acpi_smbus_cmi_ids); + +#define ACPI_SMBUS_STATUS_OK 0x00 +#define ACPI_SMBUS_STATUS_FAIL 0x07 +#define ACPI_SMBUS_STATUS_DNAK 0x10 +#define ACPI_SMBUS_STATUS_DERR 0x11 +#define ACPI_SMBUS_STATUS_CMD_DENY 0x12 +#define ACPI_SMBUS_STATUS_UNKNOWN 0x13 +#define ACPI_SMBUS_STATUS_ACC_DENY 0x17 +#define ACPI_SMBUS_STATUS_TIMEOUT 0x18 +#define ACPI_SMBUS_STATUS_NOTSUP 0x19 +#define ACPI_SMBUS_STATUS_BUSY 0x1a +#define ACPI_SMBUS_STATUS_PEC 0x1f + +#define ACPI_SMBUS_PRTCL_WRITE 0x00 +#define ACPI_SMBUS_PRTCL_READ 0x01 +#define ACPI_SMBUS_PRTCL_QUICK 0x02 +#define ACPI_SMBUS_PRTCL_BYTE 0x04 +#define ACPI_SMBUS_PRTCL_BYTE_DATA 0x06 +#define ACPI_SMBUS_PRTCL_WORD_DATA 0x08 +#define ACPI_SMBUS_PRTCL_BLOCK_DATA 0x0a + + +static int +acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags, + char read_write, u8 command, int size, + union i2c_smbus_data *data) +{ + int result = 0; + struct acpi_smbus_cmi *smbus_cmi = adap->algo_data; + unsigned char protocol; + acpi_status status = 0; + struct acpi_object_list input; + union acpi_object mt_params[5]; + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + union acpi_object *obj; + union acpi_object *pkg; + char *method; + int len = 0; + + dev_dbg(&adap->dev, "access size: %d %s\n", size, + (read_write) ? "READ" : "WRITE"); + switch (size) { + case I2C_SMBUS_QUICK: + protocol = ACPI_SMBUS_PRTCL_QUICK; + command = 0; + if (read_write == I2C_SMBUS_WRITE) { + mt_params[3].type = ACPI_TYPE_INTEGER; + mt_params[3].integer.value = 0; + mt_params[4].type = ACPI_TYPE_INTEGER; + mt_params[4].integer.value = 0; + } + break; + + case I2C_SMBUS_BYTE: + protocol = ACPI_SMBUS_PRTCL_BYTE; + if (read_write == I2C_SMBUS_WRITE) { + mt_params[3].type = ACPI_TYPE_INTEGER; + mt_params[3].integer.value = 0; + mt_params[4].type = ACPI_TYPE_INTEGER; + mt_params[4].integer.value = 0; + } else { + command = 0; + } + break; + + case I2C_SMBUS_BYTE_DATA: + protocol = ACPI_SMBUS_PRTCL_BYTE_DATA; + if (read_write == I2C_SMBUS_WRITE) { + mt_params[3].type = ACPI_TYPE_INTEGER; + mt_params[3].integer.value = 1; + mt_params[4].type = ACPI_TYPE_INTEGER; + mt_params[4].integer.value = data->byte; + } + break; + + case I2C_SMBUS_WORD_DATA: + protocol = ACPI_SMBUS_PRTCL_WORD_DATA; + if (read_write == I2C_SMBUS_WRITE) { + mt_params[3].type = ACPI_TYPE_INTEGER; + mt_params[3].integer.value = 2; + mt_params[4].type = ACPI_TYPE_INTEGER; + mt_params[4].integer.value = data->word; + } + break; + + case I2C_SMBUS_BLOCK_DATA: + protocol = ACPI_SMBUS_PRTCL_BLOCK_DATA; + if (read_write == I2C_SMBUS_WRITE) { + len = data->block[0]; + if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) + return -EINVAL; + mt_params[3].type = ACPI_TYPE_INTEGER; + mt_params[3].integer.value = len; + mt_params[4].type = ACPI_TYPE_BUFFER; + mt_params[4].buffer.length = len; + mt_params[4].buffer.pointer = data->block + 1; + } + break; + + default: + dev_warn(&adap->dev, "Unsupported transaction %d\n", size); + return -EOPNOTSUPP; + } + + if (read_write == I2C_SMBUS_READ) { + protocol |= ACPI_SMBUS_PRTCL_READ; + method = smbus_cmi->methods->mt_sbr; + input.count = 3; + } else { + protocol |= ACPI_SMBUS_PRTCL_WRITE; + method = smbus_cmi->methods->mt_sbw; + input.count = 5; + } + + input.pointer = mt_params; + mt_params[0].type = ACPI_TYPE_INTEGER; + mt_params[0].integer.value = protocol; + mt_params[1].type = ACPI_TYPE_INTEGER; + mt_params[1].integer.value = addr; + mt_params[2].type = ACPI_TYPE_INTEGER; + mt_params[2].integer.value = command; + + status = acpi_evaluate_object(smbus_cmi->handle, method, &input, + &buffer); + if (ACPI_FAILURE(status)) { + acpi_handle_err(smbus_cmi->handle, + "Failed to evaluate %s: %i\n", method, status); + return -EIO; + } + + pkg = buffer.pointer; + if (pkg && pkg->type == ACPI_TYPE_PACKAGE) + obj = pkg->package.elements; + else { + acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n"); + result = -EIO; + goto out; + } + if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) { + acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n"); + result = -EIO; + goto out; + } + + result = obj->integer.value; + acpi_handle_debug(smbus_cmi->handle, "%s return status: %i\n", method, + result); + + switch (result) { + case ACPI_SMBUS_STATUS_OK: + result = 0; + break; + case ACPI_SMBUS_STATUS_BUSY: + result = -EBUSY; + goto out; + case ACPI_SMBUS_STATUS_TIMEOUT: + result = -ETIMEDOUT; + goto out; + case ACPI_SMBUS_STATUS_DNAK: + result = -ENXIO; + goto out; + default: + result = -EIO; + goto out; + } + + if (read_write == I2C_SMBUS_WRITE || size == I2C_SMBUS_QUICK) + goto out; + + obj = pkg->package.elements + 1; + if (obj->type != ACPI_TYPE_INTEGER) { + acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n"); + result = -EIO; + goto out; + } + + len = obj->integer.value; + obj = pkg->package.elements + 2; + switch (size) { + case I2C_SMBUS_BYTE: + case I2C_SMBUS_BYTE_DATA: + case I2C_SMBUS_WORD_DATA: + if (obj->type != ACPI_TYPE_INTEGER) { + acpi_handle_err(smbus_cmi->handle, + "Invalid argument type\n"); + result = -EIO; + goto out; + } + if (len == 2) + data->word = obj->integer.value; + else + data->byte = obj->integer.value; + break; + case I2C_SMBUS_BLOCK_DATA: + if (obj->type != ACPI_TYPE_BUFFER) { + acpi_handle_err(smbus_cmi->handle, + "Invalid argument type\n"); + result = -EIO; + goto out; + } + if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) + return -EPROTO; + data->block[0] = len; + memcpy(data->block + 1, obj->buffer.pointer, len); + break; + } + +out: + kfree(buffer.pointer); + dev_dbg(&adap->dev, "Transaction status: %i\n", result); + return result; +} + +static u32 acpi_smbus_cmi_func(struct i2c_adapter *adapter) +{ + struct acpi_smbus_cmi *smbus_cmi = adapter->algo_data; + u32 ret; + + ret = smbus_cmi->cap_read | smbus_cmi->cap_write ? + I2C_FUNC_SMBUS_QUICK : 0; + + ret |= smbus_cmi->cap_read ? + (I2C_FUNC_SMBUS_READ_BYTE | + I2C_FUNC_SMBUS_READ_BYTE_DATA | + I2C_FUNC_SMBUS_READ_WORD_DATA | + I2C_FUNC_SMBUS_READ_BLOCK_DATA) : 0; + + ret |= smbus_cmi->cap_write ? + (I2C_FUNC_SMBUS_WRITE_BYTE | + I2C_FUNC_SMBUS_WRITE_BYTE_DATA | + I2C_FUNC_SMBUS_WRITE_WORD_DATA | + I2C_FUNC_SMBUS_WRITE_BLOCK_DATA) : 0; + + return ret; +} + +static const struct i2c_algorithm acpi_smbus_cmi_algorithm = { + .smbus_xfer = acpi_smbus_cmi_access, + .functionality = acpi_smbus_cmi_func, +}; + + +static int acpi_smbus_cmi_add_cap(struct acpi_smbus_cmi *smbus_cmi, + const char *name) +{ + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + struct acpi_handle *handle = smbus_cmi->handle; + union acpi_object *obj; + acpi_status status; + + if (!strcmp(name, smbus_cmi->methods->mt_info)) { + status = acpi_evaluate_object(smbus_cmi->handle, + smbus_cmi->methods->mt_info, + NULL, &buffer); + if (ACPI_FAILURE(status)) { + acpi_handle_err(handle, "Failed to evaluate %s: %i\n", + smbus_cmi->methods->mt_info, status); + return -EIO; + } + + obj = buffer.pointer; + if (obj && obj->type == ACPI_TYPE_PACKAGE) + obj = obj->package.elements; + else { + acpi_handle_err(handle, "Invalid argument type\n"); + kfree(buffer.pointer); + return -EIO; + } + + if (obj->type != ACPI_TYPE_INTEGER) { + acpi_handle_err(handle, "Invalid argument type\n"); + kfree(buffer.pointer); + return -EIO; + } else + acpi_handle_debug(handle, "SMBus CMI Version %x\n", + (int)obj->integer.value); + + kfree(buffer.pointer); + smbus_cmi->cap_info = 1; + } else if (!strcmp(name, smbus_cmi->methods->mt_sbr)) + smbus_cmi->cap_read = 1; + else if (!strcmp(name, smbus_cmi->methods->mt_sbw)) + smbus_cmi->cap_write = 1; + else + acpi_handle_debug(handle, "Unsupported CMI method: %s\n", name); + + return 0; +} + +static acpi_status acpi_smbus_cmi_query_methods(acpi_handle handle, u32 level, + void *context, void **return_value) +{ + char node_name[5]; + struct acpi_buffer buffer = { sizeof(node_name), node_name }; + struct acpi_smbus_cmi *smbus_cmi = context; + acpi_status status; + + status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); + + if (ACPI_SUCCESS(status)) + acpi_smbus_cmi_add_cap(smbus_cmi, node_name); + + return AE_OK; +} + +static int smbus_cmi_probe(struct platform_device *device) +{ + struct device *dev = &device->dev; + struct acpi_smbus_cmi *smbus_cmi; + int ret; + + smbus_cmi = kzalloc(sizeof(struct acpi_smbus_cmi), GFP_KERNEL); + if (!smbus_cmi) + return -ENOMEM; + + smbus_cmi->handle = ACPI_HANDLE(dev); + smbus_cmi->methods = device_get_match_data(dev); + + platform_set_drvdata(device, smbus_cmi); + + smbus_cmi->cap_info = 0; + smbus_cmi->cap_read = 0; + smbus_cmi->cap_write = 0; + + acpi_walk_namespace(ACPI_TYPE_METHOD, smbus_cmi->handle, 1, + acpi_smbus_cmi_query_methods, NULL, smbus_cmi, NULL); + + if (smbus_cmi->cap_info == 0) { + ret = -ENODEV; + goto err; + } + + snprintf(smbus_cmi->adapter.name, sizeof(smbus_cmi->adapter.name), + "SMBus CMI adapter %s", dev_name(dev)); + smbus_cmi->adapter.owner = THIS_MODULE; + smbus_cmi->adapter.algo = &acpi_smbus_cmi_algorithm; + smbus_cmi->adapter.algo_data = smbus_cmi; + smbus_cmi->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + smbus_cmi->adapter.dev.parent = &device->dev; + + ret = i2c_add_adapter(&smbus_cmi->adapter); + if (ret) { + dev_err(&device->dev, "Couldn't register adapter!\n"); + goto err; + } + + return 0; + +err: + kfree(smbus_cmi); + return ret; +} + +static void smbus_cmi_remove(struct platform_device *device) +{ + struct acpi_smbus_cmi *smbus_cmi = platform_get_drvdata(device); + + i2c_del_adapter(&smbus_cmi->adapter); + kfree(smbus_cmi); +} + +static struct platform_driver smbus_cmi_driver = { + .probe = smbus_cmi_probe, + .remove_new = smbus_cmi_remove, + .driver = { + .name = "smbus_cmi", + .acpi_match_table = acpi_smbus_cmi_ids, + }, +}; +module_platform_driver(smbus_cmi_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Crane Cai <crane.cai@amd.com>"); +MODULE_DESCRIPTION("ACPI SMBus CMI driver"); diff --git a/drivers/i2c/busses/i2c-sh7760.c b/drivers/i2c/busses/i2c-sh7760.c new file mode 100644 index 000000000..1ad2a2615 --- /dev/null +++ b/drivers/i2c/busses/i2c-sh7760.c @@ -0,0 +1,562 @@ +/* + * I2C bus driver for the SH7760 I2C Interfaces. + * + * (c) 2005-2008 MSC Vertriebsges.m.b.H, Manuel Lauss <mlau@msc-ge.com> + * + * licensed under the terms outlined in the file COPYING. + * + */ + +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/module.h> + +#include <asm/clock.h> +#include <asm/i2c-sh7760.h> + +/* register offsets */ +#define I2CSCR 0x0 /* slave ctrl */ +#define I2CMCR 0x4 /* master ctrl */ +#define I2CSSR 0x8 /* slave status */ +#define I2CMSR 0xC /* master status */ +#define I2CSIER 0x10 /* slave irq enable */ +#define I2CMIER 0x14 /* master irq enable */ +#define I2CCCR 0x18 /* clock dividers */ +#define I2CSAR 0x1c /* slave address */ +#define I2CMAR 0x20 /* master address */ +#define I2CRXTX 0x24 /* data port */ +#define I2CFCR 0x28 /* fifo control */ +#define I2CFSR 0x2C /* fifo status */ +#define I2CFIER 0x30 /* fifo irq enable */ +#define I2CRFDR 0x34 /* rx fifo count */ +#define I2CTFDR 0x38 /* tx fifo count */ + +#define REGSIZE 0x3C + +#define MCR_MDBS 0x80 /* non-fifo mode switch */ +#define MCR_FSCL 0x40 /* override SCL pin */ +#define MCR_FSDA 0x20 /* override SDA pin */ +#define MCR_OBPC 0x10 /* override pins */ +#define MCR_MIE 0x08 /* master if enable */ +#define MCR_TSBE 0x04 +#define MCR_FSB 0x02 /* force stop bit */ +#define MCR_ESG 0x01 /* en startbit gen. */ + +#define MSR_MNR 0x40 /* nack received */ +#define MSR_MAL 0x20 /* arbitration lost */ +#define MSR_MST 0x10 /* sent a stop */ +#define MSR_MDE 0x08 +#define MSR_MDT 0x04 +#define MSR_MDR 0x02 +#define MSR_MAT 0x01 /* slave addr xfer done */ + +#define MIE_MNRE 0x40 /* nack irq en */ +#define MIE_MALE 0x20 /* arblos irq en */ +#define MIE_MSTE 0x10 /* stop irq en */ +#define MIE_MDEE 0x08 +#define MIE_MDTE 0x04 +#define MIE_MDRE 0x02 +#define MIE_MATE 0x01 /* address sent irq en */ + +#define FCR_RFRST 0x02 /* reset rx fifo */ +#define FCR_TFRST 0x01 /* reset tx fifo */ + +#define FSR_TEND 0x04 /* last byte sent */ +#define FSR_RDF 0x02 /* rx fifo trigger */ +#define FSR_TDFE 0x01 /* tx fifo empty */ + +#define FIER_TEIE 0x04 /* tx fifo empty irq en */ +#define FIER_RXIE 0x02 /* rx fifo trig irq en */ +#define FIER_TXIE 0x01 /* tx fifo trig irq en */ + +#define FIFO_SIZE 16 + +struct cami2c { + void __iomem *iobase; + struct i2c_adapter adap; + + /* message processing */ + struct i2c_msg *msg; +#define IDF_SEND 1 +#define IDF_RECV 2 +#define IDF_STOP 4 + int flags; + +#define IDS_DONE 1 +#define IDS_ARBLOST 2 +#define IDS_NACK 4 + int status; + struct completion xfer_done; + + int irq; + struct resource *ioarea; +}; + +static inline void OUT32(struct cami2c *cam, int reg, unsigned long val) +{ + __raw_writel(val, (unsigned long)cam->iobase + reg); +} + +static inline unsigned long IN32(struct cami2c *cam, int reg) +{ + return __raw_readl((unsigned long)cam->iobase + reg); +} + +static irqreturn_t sh7760_i2c_irq(int irq, void *ptr) +{ + struct cami2c *id = ptr; + struct i2c_msg *msg = id->msg; + char *data = msg->buf; + unsigned long msr, fsr, fier, len; + + msr = IN32(id, I2CMSR); + fsr = IN32(id, I2CFSR); + + /* arbitration lost */ + if (msr & MSR_MAL) { + OUT32(id, I2CMCR, 0); + OUT32(id, I2CSCR, 0); + OUT32(id, I2CSAR, 0); + id->status |= IDS_DONE | IDS_ARBLOST; + goto out; + } + + if (msr & MSR_MNR) { + /* NACK handling is very screwed up. After receiving a + * NAK IRQ one has to wait a bit before writing to any + * registers, or the ctl will lock up. After that delay + * do a normal i2c stop. Then wait at least 1 ms before + * attempting another transfer or ctl will stop working + */ + udelay(100); /* wait or risk ctl hang */ + OUT32(id, I2CFCR, FCR_RFRST | FCR_TFRST); + OUT32(id, I2CMCR, MCR_MIE | MCR_FSB); + OUT32(id, I2CFIER, 0); + OUT32(id, I2CMIER, MIE_MSTE); + OUT32(id, I2CSCR, 0); + OUT32(id, I2CSAR, 0); + id->status |= IDS_NACK; + msr &= ~MSR_MAT; + fsr = 0; + /* In some cases the MST bit is also set. */ + } + + /* i2c-stop was sent */ + if (msr & MSR_MST) { + id->status |= IDS_DONE; + goto out; + } + + /* i2c slave addr was sent; set to "normal" operation */ + if (msr & MSR_MAT) + OUT32(id, I2CMCR, MCR_MIE); + + fier = IN32(id, I2CFIER); + + if (fsr & FSR_RDF) { + len = IN32(id, I2CRFDR); + if (msg->len <= len) { + if (id->flags & IDF_STOP) { + OUT32(id, I2CMCR, MCR_MIE | MCR_FSB); + OUT32(id, I2CFIER, 0); + /* manual says: wait >= 0.5 SCL times */ + udelay(5); + /* next int should be MST */ + } else { + id->status |= IDS_DONE; + /* keep the RDF bit: ctrl holds SCL low + * until the setup for the next i2c_msg + * clears this bit. + */ + fsr &= ~FSR_RDF; + } + } + while (msg->len && len) { + *data++ = IN32(id, I2CRXTX); + msg->len--; + len--; + } + + if (msg->len) { + len = (msg->len >= FIFO_SIZE) ? FIFO_SIZE - 1 + : msg->len - 1; + + OUT32(id, I2CFCR, FCR_TFRST | ((len & 0xf) << 4)); + } + + } else if (id->flags & IDF_SEND) { + if ((fsr & FSR_TEND) && (msg->len < 1)) { + if (id->flags & IDF_STOP) { + OUT32(id, I2CMCR, MCR_MIE | MCR_FSB); + } else { + id->status |= IDS_DONE; + /* keep the TEND bit: ctl holds SCL low + * until the setup for the next i2c_msg + * clears this bit. + */ + fsr &= ~FSR_TEND; + } + } + if (fsr & FSR_TDFE) { + while (msg->len && (IN32(id, I2CTFDR) < FIFO_SIZE)) { + OUT32(id, I2CRXTX, *data++); + msg->len--; + } + + if (msg->len < 1) { + fier &= ~FIER_TXIE; + OUT32(id, I2CFIER, fier); + } else { + len = (msg->len >= FIFO_SIZE) ? 2 : 0; + OUT32(id, I2CFCR, + FCR_RFRST | ((len & 3) << 2)); + } + } + } +out: + if (id->status & IDS_DONE) { + OUT32(id, I2CMIER, 0); + OUT32(id, I2CFIER, 0); + id->msg = NULL; + complete(&id->xfer_done); + } + /* clear status flags and ctrl resumes work */ + OUT32(id, I2CMSR, ~msr); + OUT32(id, I2CFSR, ~fsr); + OUT32(id, I2CSSR, 0); + + return IRQ_HANDLED; +} + + +/* prepare and start a master receive operation */ +static void sh7760_i2c_mrecv(struct cami2c *id) +{ + int len; + + id->flags |= IDF_RECV; + + /* set the slave addr reg; otherwise rcv wont work! */ + OUT32(id, I2CSAR, 0xfe); + OUT32(id, I2CMAR, (id->msg->addr << 1) | 1); + + /* adjust rx fifo trigger */ + if (id->msg->len >= FIFO_SIZE) + len = FIFO_SIZE - 1; /* trigger at fifo full */ + else + len = id->msg->len - 1; /* trigger before all received */ + + OUT32(id, I2CFCR, FCR_RFRST | FCR_TFRST); + OUT32(id, I2CFCR, FCR_TFRST | ((len & 0xF) << 4)); + + OUT32(id, I2CMSR, 0); + OUT32(id, I2CMCR, MCR_MIE | MCR_ESG); + OUT32(id, I2CMIER, MIE_MNRE | MIE_MALE | MIE_MSTE | MIE_MATE); + OUT32(id, I2CFIER, FIER_RXIE); +} + +/* prepare and start a master send operation */ +static void sh7760_i2c_msend(struct cami2c *id) +{ + int len; + + id->flags |= IDF_SEND; + + /* set the slave addr reg; otherwise xmit wont work! */ + OUT32(id, I2CSAR, 0xfe); + OUT32(id, I2CMAR, (id->msg->addr << 1) | 0); + + /* adjust tx fifo trigger */ + if (id->msg->len >= FIFO_SIZE) + len = 2; /* trig: 2 bytes left in TX fifo */ + else + len = 0; /* trig: 8 bytes left in TX fifo */ + + OUT32(id, I2CFCR, FCR_RFRST | FCR_TFRST); + OUT32(id, I2CFCR, FCR_RFRST | ((len & 3) << 2)); + + while (id->msg->len && IN32(id, I2CTFDR) < FIFO_SIZE) { + OUT32(id, I2CRXTX, *(id->msg->buf)); + (id->msg->len)--; + (id->msg->buf)++; + } + + OUT32(id, I2CMSR, 0); + OUT32(id, I2CMCR, MCR_MIE | MCR_ESG); + OUT32(id, I2CFSR, 0); + OUT32(id, I2CMIER, MIE_MNRE | MIE_MALE | MIE_MSTE | MIE_MATE); + OUT32(id, I2CFIER, FIER_TEIE | (id->msg->len ? FIER_TXIE : 0)); +} + +static inline int sh7760_i2c_busy_check(struct cami2c *id) +{ + return (IN32(id, I2CMCR) & MCR_FSDA); +} + +static int sh7760_i2c_master_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, + int num) +{ + struct cami2c *id = adap->algo_data; + int i, retr; + + if (sh7760_i2c_busy_check(id)) { + dev_err(&adap->dev, "sh7760-i2c%d: bus busy!\n", adap->nr); + return -EBUSY; + } + + i = 0; + while (i < num) { + retr = adap->retries; +retry: + id->flags = ((i == (num-1)) ? IDF_STOP : 0); + id->status = 0; + id->msg = msgs; + init_completion(&id->xfer_done); + + if (msgs->flags & I2C_M_RD) + sh7760_i2c_mrecv(id); + else + sh7760_i2c_msend(id); + + wait_for_completion(&id->xfer_done); + + if (id->status == 0) { + num = -EIO; + break; + } + + if (id->status & IDS_NACK) { + /* wait a bit or i2c module stops working */ + mdelay(1); + num = -EREMOTEIO; + break; + } + + if (id->status & IDS_ARBLOST) { + if (retr--) { + mdelay(2); + goto retry; + } + num = -EREMOTEIO; + break; + } + + msgs++; + i++; + } + + id->msg = NULL; + id->flags = 0; + id->status = 0; + + OUT32(id, I2CMCR, 0); + OUT32(id, I2CMSR, 0); + OUT32(id, I2CMIER, 0); + OUT32(id, I2CFIER, 0); + + /* reset slave module registers too: master mode enables slave + * module for receive ops (ack, data). Without this reset, + * eternal bus activity might be reported after NACK / ARBLOST. + */ + OUT32(id, I2CSCR, 0); + OUT32(id, I2CSAR, 0); + OUT32(id, I2CSSR, 0); + + return num; +} + +static u32 sh7760_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); +} + +static const struct i2c_algorithm sh7760_i2c_algo = { + .master_xfer = sh7760_i2c_master_xfer, + .functionality = sh7760_i2c_func, +}; + +/* calculate CCR register setting for a desired scl clock. SCL clock is + * derived from I2C module clock (iclk) which in turn is derived from + * peripheral module clock (mclk, usually around 33MHz): + * iclk = mclk/(CDF + 1). iclk must be < 20MHz. + * scl = iclk/(SCGD*8 + 20). + */ +static int calc_CCR(unsigned long scl_hz) +{ + struct clk *mclk; + unsigned long mck, m1, dff, odff, iclk; + signed char cdf, cdfm; + int scgd, scgdm, scgds; + + mclk = clk_get(NULL, "peripheral_clk"); + if (IS_ERR(mclk)) { + return PTR_ERR(mclk); + } else { + mck = mclk->rate; + clk_put(mclk); + } + + odff = scl_hz; + scgdm = cdfm = m1 = 0; + for (cdf = 3; cdf >= 0; cdf--) { + iclk = mck / (1 + cdf); + if (iclk >= 20000000) + continue; + scgds = ((iclk / scl_hz) - 20) >> 3; + for (scgd = scgds; (scgd < 63) && scgd <= scgds + 1; scgd++) { + m1 = iclk / (20 + (scgd << 3)); + dff = abs(scl_hz - m1); + if (dff < odff) { + odff = dff; + cdfm = cdf; + scgdm = scgd; + } + } + } + /* fail if more than 25% off of requested SCL */ + if (odff > (scl_hz >> 2)) + return -EINVAL; + + /* create a CCR register value */ + return ((scgdm << 2) | cdfm); +} + +static int sh7760_i2c_probe(struct platform_device *pdev) +{ + struct sh7760_i2c_platdata *pd; + struct resource *res; + struct cami2c *id; + int ret; + + pd = dev_get_platdata(&pdev->dev); + if (!pd) { + dev_err(&pdev->dev, "no platform_data!\n"); + ret = -ENODEV; + goto out0; + } + + id = kzalloc(sizeof(*id), GFP_KERNEL); + if (!id) { + ret = -ENOMEM; + goto out0; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "no mmio resources\n"); + ret = -ENODEV; + goto out1; + } + + id->ioarea = request_mem_region(res->start, REGSIZE, pdev->name); + if (!id->ioarea) { + dev_err(&pdev->dev, "mmio already reserved\n"); + ret = -EBUSY; + goto out1; + } + + id->iobase = ioremap(res->start, REGSIZE); + if (!id->iobase) { + dev_err(&pdev->dev, "cannot ioremap\n"); + ret = -ENODEV; + goto out2; + } + + ret = platform_get_irq(pdev, 0); + if (ret < 0) + goto out3; + id->irq = ret; + + id->adap.nr = pdev->id; + id->adap.algo = &sh7760_i2c_algo; + id->adap.class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + id->adap.retries = 3; + id->adap.algo_data = id; + id->adap.dev.parent = &pdev->dev; + snprintf(id->adap.name, sizeof(id->adap.name), + "SH7760 I2C at %08lx", (unsigned long)res->start); + + OUT32(id, I2CMCR, 0); + OUT32(id, I2CMSR, 0); + OUT32(id, I2CMIER, 0); + OUT32(id, I2CMAR, 0); + OUT32(id, I2CSIER, 0); + OUT32(id, I2CSAR, 0); + OUT32(id, I2CSCR, 0); + OUT32(id, I2CSSR, 0); + OUT32(id, I2CFIER, 0); + OUT32(id, I2CFCR, FCR_RFRST | FCR_TFRST); + OUT32(id, I2CFSR, 0); + + ret = calc_CCR(pd->speed_khz * 1000); + if (ret < 0) { + dev_err(&pdev->dev, "invalid SCL clock: %dkHz\n", + pd->speed_khz); + goto out3; + } + OUT32(id, I2CCCR, ret); + + if (request_irq(id->irq, sh7760_i2c_irq, 0, + SH7760_I2C_DEVNAME, id)) { + dev_err(&pdev->dev, "cannot get irq %d\n", id->irq); + ret = -EBUSY; + goto out3; + } + + ret = i2c_add_numbered_adapter(&id->adap); + if (ret < 0) + goto out4; + + platform_set_drvdata(pdev, id); + + dev_info(&pdev->dev, "%d kHz mmio %08x irq %d\n", + pd->speed_khz, res->start, id->irq); + + return 0; + +out4: + free_irq(id->irq, id); +out3: + iounmap(id->iobase); +out2: + release_resource(id->ioarea); + kfree(id->ioarea); +out1: + kfree(id); +out0: + return ret; +} + +static void sh7760_i2c_remove(struct platform_device *pdev) +{ + struct cami2c *id = platform_get_drvdata(pdev); + + i2c_del_adapter(&id->adap); + free_irq(id->irq, id); + iounmap(id->iobase); + release_resource(id->ioarea); + kfree(id->ioarea); + kfree(id); +} + +static struct platform_driver sh7760_i2c_drv = { + .driver = { + .name = SH7760_I2C_DEVNAME, + }, + .probe = sh7760_i2c_probe, + .remove_new = sh7760_i2c_remove, +}; + +module_platform_driver(sh7760_i2c_drv); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("SH7760 I2C bus driver"); +MODULE_AUTHOR("Manuel Lauss <mano@roarinelk.homelinux.net>"); diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c new file mode 100644 index 000000000..5adbe62cf --- /dev/null +++ b/drivers/i2c/busses/i2c-sh_mobile.c @@ -0,0 +1,1011 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * SuperH Mobile I2C Controller + * + * Copyright (C) 2014-19 Wolfram Sang <wsa@sang-engineering.com> + * Copyright (C) 2008 Magnus Damm + * + * Portions of the code based on out-of-tree driver i2c-sh7343.c + * Copyright (c) 2006 Carlos Munoz <carlos@kenati.com> + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/slab.h> + +/* Transmit operation: */ +/* */ +/* 0 byte transmit */ +/* BUS: S A8 ACK P(*) */ +/* IRQ: DTE WAIT */ +/* ICIC: */ +/* ICCR: 0x94 0x90 */ +/* ICDR: A8 */ +/* */ +/* 1 byte transmit */ +/* BUS: S A8 ACK D8(1) ACK P(*) */ +/* IRQ: DTE WAIT WAIT */ +/* ICIC: -DTE */ +/* ICCR: 0x94 0x90 */ +/* ICDR: A8 D8(1) */ +/* */ +/* 2 byte transmit */ +/* BUS: S A8 ACK D8(1) ACK D8(2) ACK P(*) */ +/* IRQ: DTE WAIT WAIT WAIT */ +/* ICIC: -DTE */ +/* ICCR: 0x94 0x90 */ +/* ICDR: A8 D8(1) D8(2) */ +/* */ +/* 3 bytes or more, +---------+ gets repeated */ +/* */ +/* */ +/* Receive operation: */ +/* */ +/* 0 byte receive - not supported since slave may hold SDA low */ +/* */ +/* 1 byte receive [TX] | [RX] */ +/* BUS: S A8 ACK | D8(1) ACK P(*) */ +/* IRQ: DTE WAIT | WAIT DTE */ +/* ICIC: -DTE | +DTE */ +/* ICCR: 0x94 0x81 | 0xc0 */ +/* ICDR: A8 | D8(1) */ +/* */ +/* 2 byte receive [TX]| [RX] */ +/* BUS: S A8 ACK | D8(1) ACK D8(2) ACK P(*) */ +/* IRQ: DTE WAIT | WAIT WAIT DTE */ +/* ICIC: -DTE | +DTE */ +/* ICCR: 0x94 0x81 | 0xc0 */ +/* ICDR: A8 | D8(1) D8(2) */ +/* */ +/* 3 byte receive [TX] | [RX] (*) */ +/* BUS: S A8 ACK | D8(1) ACK D8(2) ACK D8(3) ACK P */ +/* IRQ: DTE WAIT | WAIT WAIT WAIT DTE */ +/* ICIC: -DTE | +DTE */ +/* ICCR: 0x94 0x81 | 0xc0 */ +/* ICDR: A8 | D8(1) D8(2) D8(3) */ +/* */ +/* 4 bytes or more, this part is repeated +---------+ */ +/* */ +/* */ +/* Interrupt order and BUSY flag */ +/* ___ _ */ +/* SDA ___\___XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXAAAAAAAAA___/ */ +/* SCL \_/1\_/2\_/3\_/4\_/5\_/6\_/7\_/8\___/9\_____/ */ +/* */ +/* S D7 D6 D5 D4 D3 D2 D1 D0 P(*) */ +/* ___ */ +/* WAIT IRQ ________________________________/ \___________ */ +/* TACK IRQ ____________________________________/ \_______ */ +/* DTE IRQ __________________________________________/ \_ */ +/* AL IRQ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */ +/* _______________________________________________ */ +/* BUSY __/ \_ */ +/* */ +/* (*) The STOP condition is only sent by the master at the end of the last */ +/* I2C message or if the I2C_M_STOP flag is set. Similarly, the BUSY bit is */ +/* only cleared after the STOP condition, so, between messages we have to */ +/* poll for the DTE bit. */ +/* */ + +enum sh_mobile_i2c_op { + OP_START = 0, + OP_TX_FIRST, + OP_TX, + OP_TX_STOP, + OP_TX_TO_RX, + OP_RX, + OP_RX_STOP, + OP_RX_STOP_DATA, +}; + +struct sh_mobile_i2c_data { + struct device *dev; + void __iomem *reg; + struct i2c_adapter adap; + unsigned long bus_speed; + unsigned int clks_per_count; + struct clk *clk; + u_int8_t icic; + u_int8_t flags; + u_int16_t iccl; + u_int16_t icch; + + spinlock_t lock; + wait_queue_head_t wait; + struct i2c_msg *msg; + int pos; + int sr; + bool send_stop; + bool stop_after_dma; + bool atomic_xfer; + + struct resource *res; + struct dma_chan *dma_tx; + struct dma_chan *dma_rx; + struct scatterlist sg; + enum dma_data_direction dma_direction; + u8 *dma_buf; +}; + +struct sh_mobile_dt_config { + int clks_per_count; + int (*setup)(struct sh_mobile_i2c_data *pd); +}; + +#define IIC_FLAG_HAS_ICIC67 (1 << 0) + +/* Register offsets */ +#define ICDR 0x00 +#define ICCR 0x04 +#define ICSR 0x08 +#define ICIC 0x0c +#define ICCL 0x10 +#define ICCH 0x14 +#define ICSTART 0x70 + +/* Register bits */ +#define ICCR_ICE 0x80 +#define ICCR_RACK 0x40 +#define ICCR_TRS 0x10 +#define ICCR_BBSY 0x04 +#define ICCR_SCP 0x01 + +#define ICSR_SCLM 0x80 +#define ICSR_SDAM 0x40 +#define SW_DONE 0x20 +#define ICSR_BUSY 0x10 +#define ICSR_AL 0x08 +#define ICSR_TACK 0x04 +#define ICSR_WAIT 0x02 +#define ICSR_DTE 0x01 + +#define ICIC_ICCLB8 0x80 +#define ICIC_ICCHB8 0x40 +#define ICIC_TDMAE 0x20 +#define ICIC_RDMAE 0x10 +#define ICIC_ALE 0x08 +#define ICIC_TACKE 0x04 +#define ICIC_WAITE 0x02 +#define ICIC_DTEE 0x01 + +#define ICSTART_ICSTART 0x10 + +static void iic_wr(struct sh_mobile_i2c_data *pd, int offs, unsigned char data) +{ + if (offs == ICIC) + data |= pd->icic; + + iowrite8(data, pd->reg + offs); +} + +static unsigned char iic_rd(struct sh_mobile_i2c_data *pd, int offs) +{ + return ioread8(pd->reg + offs); +} + +static void iic_set_clr(struct sh_mobile_i2c_data *pd, int offs, + unsigned char set, unsigned char clr) +{ + iic_wr(pd, offs, (iic_rd(pd, offs) | set) & ~clr); +} + +static u32 sh_mobile_i2c_iccl(unsigned long count_khz, u32 tLOW, u32 tf) +{ + /* + * Conditional expression: + * ICCL >= COUNT_CLK * (tLOW + tf) + * + * SH-Mobile IIC hardware starts counting the LOW period of + * the SCL signal (tLOW) as soon as it pulls the SCL line. + * In order to meet the tLOW timing spec, we need to take into + * account the fall time of SCL signal (tf). Default tf value + * should be 0.3 us, for safety. + */ + return (((count_khz * (tLOW + tf)) + 5000) / 10000); +} + +static u32 sh_mobile_i2c_icch(unsigned long count_khz, u32 tHIGH, u32 tf) +{ + /* + * Conditional expression: + * ICCH >= COUNT_CLK * (tHIGH + tf) + * + * SH-Mobile IIC hardware is aware of SCL transition period 'tr', + * and can ignore it. SH-Mobile IIC controller starts counting + * the HIGH period of the SCL signal (tHIGH) after the SCL input + * voltage increases at VIH. + * + * Afterward it turned out calculating ICCH using only tHIGH spec + * will result in violation of the tHD;STA timing spec. We need + * to take into account the fall time of SDA signal (tf) at START + * condition, in order to meet both tHIGH and tHD;STA specs. + */ + return (((count_khz * (tHIGH + tf)) + 5000) / 10000); +} + +static int sh_mobile_i2c_check_timing(struct sh_mobile_i2c_data *pd) +{ + u16 max_val = pd->flags & IIC_FLAG_HAS_ICIC67 ? 0x1ff : 0xff; + + if (pd->iccl > max_val || pd->icch > max_val) { + dev_err(pd->dev, "timing values out of range: L/H=0x%x/0x%x\n", + pd->iccl, pd->icch); + return -EINVAL; + } + + /* one more bit of ICCL in ICIC */ + if (pd->iccl & 0x100) + pd->icic |= ICIC_ICCLB8; + else + pd->icic &= ~ICIC_ICCLB8; + + /* one more bit of ICCH in ICIC */ + if (pd->icch & 0x100) + pd->icic |= ICIC_ICCHB8; + else + pd->icic &= ~ICIC_ICCHB8; + + dev_dbg(pd->dev, "timing values: L/H=0x%x/0x%x\n", pd->iccl, pd->icch); + return 0; +} + +static int sh_mobile_i2c_init(struct sh_mobile_i2c_data *pd) +{ + unsigned long i2c_clk_khz; + u32 tHIGH, tLOW, tf; + + i2c_clk_khz = clk_get_rate(pd->clk) / 1000 / pd->clks_per_count; + + if (pd->bus_speed == I2C_MAX_STANDARD_MODE_FREQ) { + tLOW = 47; /* tLOW = 4.7 us */ + tHIGH = 40; /* tHD;STA = tHIGH = 4.0 us */ + tf = 3; /* tf = 0.3 us */ + } else if (pd->bus_speed == I2C_MAX_FAST_MODE_FREQ) { + tLOW = 13; /* tLOW = 1.3 us */ + tHIGH = 6; /* tHD;STA = tHIGH = 0.6 us */ + tf = 3; /* tf = 0.3 us */ + } else { + dev_err(pd->dev, "unrecognized bus speed %lu Hz\n", + pd->bus_speed); + return -EINVAL; + } + + pd->iccl = sh_mobile_i2c_iccl(i2c_clk_khz, tLOW, tf); + pd->icch = sh_mobile_i2c_icch(i2c_clk_khz, tHIGH, tf); + + return sh_mobile_i2c_check_timing(pd); +} + +static int sh_mobile_i2c_v2_init(struct sh_mobile_i2c_data *pd) +{ + unsigned long clks_per_cycle; + + /* L = 5, H = 4, L + H = 9 */ + clks_per_cycle = clk_get_rate(pd->clk) / pd->bus_speed; + pd->iccl = DIV_ROUND_UP(clks_per_cycle * 5 / 9 - 1, pd->clks_per_count); + pd->icch = DIV_ROUND_UP(clks_per_cycle * 4 / 9 - 5, pd->clks_per_count); + + return sh_mobile_i2c_check_timing(pd); +} + +static unsigned char i2c_op(struct sh_mobile_i2c_data *pd, enum sh_mobile_i2c_op op) +{ + unsigned char ret = 0; + unsigned long flags; + + dev_dbg(pd->dev, "op %d\n", op); + + spin_lock_irqsave(&pd->lock, flags); + + switch (op) { + case OP_START: /* issue start and trigger DTE interrupt */ + iic_wr(pd, ICCR, ICCR_ICE | ICCR_TRS | ICCR_BBSY); + break; + case OP_TX_FIRST: /* disable DTE interrupt and write client address */ + iic_wr(pd, ICIC, ICIC_WAITE | ICIC_ALE | ICIC_TACKE); + iic_wr(pd, ICDR, i2c_8bit_addr_from_msg(pd->msg)); + break; + case OP_TX: /* write data */ + iic_wr(pd, ICDR, pd->msg->buf[pd->pos]); + break; + case OP_TX_STOP: /* issue a stop (or rep_start) */ + iic_wr(pd, ICCR, pd->send_stop ? ICCR_ICE | ICCR_TRS + : ICCR_ICE | ICCR_TRS | ICCR_BBSY); + break; + case OP_TX_TO_RX: /* select read mode */ + iic_wr(pd, ICCR, ICCR_ICE | ICCR_SCP); + break; + case OP_RX: /* just read data */ + ret = iic_rd(pd, ICDR); + break; + case OP_RX_STOP: /* enable DTE interrupt, issue stop */ + if (!pd->atomic_xfer) + iic_wr(pd, ICIC, + ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); + iic_wr(pd, ICCR, ICCR_ICE | ICCR_RACK); + break; + case OP_RX_STOP_DATA: /* enable DTE interrupt, read data, issue stop */ + if (!pd->atomic_xfer) + iic_wr(pd, ICIC, + ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); + ret = iic_rd(pd, ICDR); + iic_wr(pd, ICCR, ICCR_ICE | ICCR_RACK); + break; + } + + spin_unlock_irqrestore(&pd->lock, flags); + + dev_dbg(pd->dev, "op %d, data out 0x%02x\n", op, ret); + return ret; +} + +static int sh_mobile_i2c_isr_tx(struct sh_mobile_i2c_data *pd) +{ + if (pd->pos == pd->msg->len) { + i2c_op(pd, OP_TX_STOP); + return 1; + } + + if (pd->pos == -1) + i2c_op(pd, OP_TX_FIRST); + else + i2c_op(pd, OP_TX); + + pd->pos++; + return 0; +} + +static int sh_mobile_i2c_isr_rx(struct sh_mobile_i2c_data *pd) +{ + int real_pos; + + /* switch from TX (address) to RX (data) adds two interrupts */ + real_pos = pd->pos - 2; + + if (pd->pos == -1) { + i2c_op(pd, OP_TX_FIRST); + } else if (pd->pos == 0) { + i2c_op(pd, OP_TX_TO_RX); + } else if (pd->pos == pd->msg->len) { + if (pd->stop_after_dma) { + /* Simulate PIO end condition after DMA transfer */ + i2c_op(pd, OP_RX_STOP); + pd->pos++; + goto done; + } + + if (real_pos < 0) + i2c_op(pd, OP_RX_STOP); + else + pd->msg->buf[real_pos] = i2c_op(pd, OP_RX_STOP_DATA); + } else if (real_pos >= 0) { + pd->msg->buf[real_pos] = i2c_op(pd, OP_RX); + } + + done: + pd->pos++; + return pd->pos == (pd->msg->len + 2); +} + +static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id) +{ + struct sh_mobile_i2c_data *pd = dev_id; + unsigned char sr; + int wakeup = 0; + + sr = iic_rd(pd, ICSR); + pd->sr |= sr; /* remember state */ + + dev_dbg(pd->dev, "i2c_isr 0x%02x 0x%02x %s %d %d!\n", sr, pd->sr, + (pd->msg->flags & I2C_M_RD) ? "read" : "write", + pd->pos, pd->msg->len); + + /* Kick off TxDMA after preface was done */ + if (pd->dma_direction == DMA_TO_DEVICE && pd->pos == 0) + iic_set_clr(pd, ICIC, ICIC_TDMAE, 0); + else if (sr & (ICSR_AL | ICSR_TACK)) + /* don't interrupt transaction - continue to issue stop */ + iic_wr(pd, ICSR, sr & ~(ICSR_AL | ICSR_TACK)); + else if (pd->msg->flags & I2C_M_RD) + wakeup = sh_mobile_i2c_isr_rx(pd); + else + wakeup = sh_mobile_i2c_isr_tx(pd); + + /* Kick off RxDMA after preface was done */ + if (pd->dma_direction == DMA_FROM_DEVICE && pd->pos == 1) + iic_set_clr(pd, ICIC, ICIC_RDMAE, 0); + + if (sr & ICSR_WAIT) /* TODO: add delay here to support slow acks */ + iic_wr(pd, ICSR, sr & ~ICSR_WAIT); + + if (wakeup) { + pd->sr |= SW_DONE; + if (!pd->atomic_xfer) + wake_up(&pd->wait); + } + + /* defeat write posting to avoid spurious WAIT interrupts */ + iic_rd(pd, ICSR); + + return IRQ_HANDLED; +} + +static void sh_mobile_i2c_cleanup_dma(struct sh_mobile_i2c_data *pd, bool terminate) +{ + struct dma_chan *chan = pd->dma_direction == DMA_FROM_DEVICE + ? pd->dma_rx : pd->dma_tx; + + /* only allowed from thread context! */ + if (terminate) + dmaengine_terminate_sync(chan); + + dma_unmap_single(chan->device->dev, sg_dma_address(&pd->sg), + pd->msg->len, pd->dma_direction); + + pd->dma_direction = DMA_NONE; +} + +static void sh_mobile_i2c_dma_callback(void *data) +{ + struct sh_mobile_i2c_data *pd = data; + + sh_mobile_i2c_cleanup_dma(pd, false); + pd->pos = pd->msg->len; + pd->stop_after_dma = true; + + iic_set_clr(pd, ICIC, 0, ICIC_TDMAE | ICIC_RDMAE); +} + +static struct dma_chan *sh_mobile_i2c_request_dma_chan(struct device *dev, + enum dma_transfer_direction dir, dma_addr_t port_addr) +{ + struct dma_chan *chan; + struct dma_slave_config cfg; + char *chan_name = dir == DMA_MEM_TO_DEV ? "tx" : "rx"; + int ret; + + chan = dma_request_chan(dev, chan_name); + if (IS_ERR(chan)) { + dev_dbg(dev, "request_channel failed for %s (%ld)\n", chan_name, + PTR_ERR(chan)); + return chan; + } + + memset(&cfg, 0, sizeof(cfg)); + cfg.direction = dir; + if (dir == DMA_MEM_TO_DEV) { + cfg.dst_addr = port_addr; + cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + } else { + cfg.src_addr = port_addr; + cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + } + + ret = dmaengine_slave_config(chan, &cfg); + if (ret) { + dev_dbg(dev, "slave_config failed for %s (%d)\n", chan_name, ret); + dma_release_channel(chan); + return ERR_PTR(ret); + } + + dev_dbg(dev, "got DMA channel for %s\n", chan_name); + return chan; +} + +static void sh_mobile_i2c_xfer_dma(struct sh_mobile_i2c_data *pd) +{ + bool read = pd->msg->flags & I2C_M_RD; + enum dma_data_direction dir = read ? DMA_FROM_DEVICE : DMA_TO_DEVICE; + struct dma_chan *chan = read ? pd->dma_rx : pd->dma_tx; + struct dma_async_tx_descriptor *txdesc; + dma_addr_t dma_addr; + dma_cookie_t cookie; + + if (PTR_ERR(chan) == -EPROBE_DEFER) { + if (read) + chan = pd->dma_rx = sh_mobile_i2c_request_dma_chan(pd->dev, DMA_DEV_TO_MEM, + pd->res->start + ICDR); + else + chan = pd->dma_tx = sh_mobile_i2c_request_dma_chan(pd->dev, DMA_MEM_TO_DEV, + pd->res->start + ICDR); + } + + if (IS_ERR(chan)) + return; + + dma_addr = dma_map_single(chan->device->dev, pd->dma_buf, pd->msg->len, dir); + if (dma_mapping_error(chan->device->dev, dma_addr)) { + dev_dbg(pd->dev, "dma map failed, using PIO\n"); + return; + } + + sg_dma_len(&pd->sg) = pd->msg->len; + sg_dma_address(&pd->sg) = dma_addr; + + pd->dma_direction = dir; + + txdesc = dmaengine_prep_slave_sg(chan, &pd->sg, 1, + read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!txdesc) { + dev_dbg(pd->dev, "dma prep slave sg failed, using PIO\n"); + sh_mobile_i2c_cleanup_dma(pd, false); + return; + } + + txdesc->callback = sh_mobile_i2c_dma_callback; + txdesc->callback_param = pd; + + cookie = dmaengine_submit(txdesc); + if (dma_submit_error(cookie)) { + dev_dbg(pd->dev, "submitting dma failed, using PIO\n"); + sh_mobile_i2c_cleanup_dma(pd, false); + return; + } + + dma_async_issue_pending(chan); +} + +static void start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg, + bool do_init) +{ + if (do_init) { + /* Initialize channel registers */ + iic_wr(pd, ICCR, ICCR_SCP); + + /* Enable channel and configure rx ack */ + iic_wr(pd, ICCR, ICCR_ICE | ICCR_SCP); + + /* Set the clock */ + iic_wr(pd, ICCL, pd->iccl & 0xff); + iic_wr(pd, ICCH, pd->icch & 0xff); + } + + pd->msg = usr_msg; + pd->pos = -1; + pd->sr = 0; + + if (pd->atomic_xfer) + return; + + pd->dma_buf = i2c_get_dma_safe_msg_buf(pd->msg, 8); + if (pd->dma_buf) + sh_mobile_i2c_xfer_dma(pd); + + /* Enable all interrupts to begin with */ + iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); +} + +static int poll_dte(struct sh_mobile_i2c_data *pd) +{ + int i; + + for (i = 1000; i; i--) { + u_int8_t val = iic_rd(pd, ICSR); + + if (val & ICSR_DTE) + break; + + if (val & ICSR_TACK) + return -ENXIO; + + udelay(10); + } + + return i ? 0 : -ETIMEDOUT; +} + +static int poll_busy(struct sh_mobile_i2c_data *pd) +{ + int i; + + for (i = 1000; i; i--) { + u_int8_t val = iic_rd(pd, ICSR); + + dev_dbg(pd->dev, "val 0x%02x pd->sr 0x%02x\n", val, pd->sr); + + /* the interrupt handler may wake us up before the + * transfer is finished, so poll the hardware + * until we're done. + */ + if (!(val & ICSR_BUSY)) { + /* handle missing acknowledge and arbitration lost */ + val |= pd->sr; + if (val & ICSR_TACK) + return -ENXIO; + if (val & ICSR_AL) + return -EAGAIN; + break; + } + + udelay(10); + } + + return i ? 0 : -ETIMEDOUT; +} + +static int sh_mobile_xfer(struct sh_mobile_i2c_data *pd, + struct i2c_msg *msgs, int num) +{ + struct i2c_msg *msg; + int err = 0; + int i; + long time_left; + + /* Wake up device and enable clock */ + pm_runtime_get_sync(pd->dev); + + /* Process all messages */ + for (i = 0; i < num; i++) { + bool do_start = pd->send_stop || !i; + msg = &msgs[i]; + pd->send_stop = i == num - 1 || msg->flags & I2C_M_STOP; + pd->stop_after_dma = false; + + start_ch(pd, msg, do_start); + + if (do_start) + i2c_op(pd, OP_START); + + if (pd->atomic_xfer) { + unsigned long j = jiffies + pd->adap.timeout; + + time_left = time_before_eq(jiffies, j); + while (time_left && + !(pd->sr & (ICSR_TACK | SW_DONE))) { + unsigned char sr = iic_rd(pd, ICSR); + + if (sr & (ICSR_AL | ICSR_TACK | + ICSR_WAIT | ICSR_DTE)) { + sh_mobile_i2c_isr(0, pd); + udelay(150); + } else { + cpu_relax(); + } + time_left = time_before_eq(jiffies, j); + } + } else { + /* The interrupt handler takes care of the rest... */ + time_left = wait_event_timeout(pd->wait, + pd->sr & (ICSR_TACK | SW_DONE), + pd->adap.timeout); + + /* 'stop_after_dma' tells if DMA xfer was complete */ + i2c_put_dma_safe_msg_buf(pd->dma_buf, pd->msg, + pd->stop_after_dma); + } + + if (!time_left) { + dev_err(pd->dev, "Transfer request timed out\n"); + if (pd->dma_direction != DMA_NONE) + sh_mobile_i2c_cleanup_dma(pd, true); + + err = -ETIMEDOUT; + break; + } + + if (pd->send_stop) + err = poll_busy(pd); + else + err = poll_dte(pd); + if (err < 0) + break; + } + + /* Disable channel */ + iic_wr(pd, ICCR, ICCR_SCP); + + /* Disable clock and mark device as idle */ + pm_runtime_put_sync(pd->dev); + + return err ?: num; +} + +static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter, + struct i2c_msg *msgs, + int num) +{ + struct sh_mobile_i2c_data *pd = i2c_get_adapdata(adapter); + + pd->atomic_xfer = false; + return sh_mobile_xfer(pd, msgs, num); +} + +static int sh_mobile_i2c_xfer_atomic(struct i2c_adapter *adapter, + struct i2c_msg *msgs, + int num) +{ + struct sh_mobile_i2c_data *pd = i2c_get_adapdata(adapter); + + pd->atomic_xfer = true; + return sh_mobile_xfer(pd, msgs, num); +} + +static u32 sh_mobile_i2c_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_PROTOCOL_MANGLING; +} + +static const struct i2c_algorithm sh_mobile_i2c_algorithm = { + .functionality = sh_mobile_i2c_func, + .master_xfer = sh_mobile_i2c_xfer, + .master_xfer_atomic = sh_mobile_i2c_xfer_atomic, +}; + +static const struct i2c_adapter_quirks sh_mobile_i2c_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN_READ, +}; + +/* + * r8a7740 has an errata regarding I2C I/O pad reset needing this workaround. + */ +static int sh_mobile_i2c_r8a7740_workaround(struct sh_mobile_i2c_data *pd) +{ + iic_set_clr(pd, ICCR, ICCR_ICE, 0); + iic_rd(pd, ICCR); /* dummy read */ + + iic_set_clr(pd, ICSTART, ICSTART_ICSTART, 0); + iic_rd(pd, ICSTART); /* dummy read */ + + udelay(10); + + iic_wr(pd, ICCR, ICCR_SCP); + iic_wr(pd, ICSTART, 0); + + udelay(10); + + iic_wr(pd, ICCR, ICCR_TRS); + udelay(10); + iic_wr(pd, ICCR, 0); + udelay(10); + iic_wr(pd, ICCR, ICCR_TRS); + udelay(10); + + return sh_mobile_i2c_init(pd); +} + +static const struct sh_mobile_dt_config default_dt_config = { + .clks_per_count = 1, + .setup = sh_mobile_i2c_init, +}; + +static const struct sh_mobile_dt_config fast_clock_dt_config = { + .clks_per_count = 2, + .setup = sh_mobile_i2c_init, +}; + +static const struct sh_mobile_dt_config v2_freq_calc_dt_config = { + .clks_per_count = 2, + .setup = sh_mobile_i2c_v2_init, +}; + +static const struct sh_mobile_dt_config r8a7740_dt_config = { + .clks_per_count = 1, + .setup = sh_mobile_i2c_r8a7740_workaround, +}; + +static const struct of_device_id sh_mobile_i2c_dt_ids[] = { + { .compatible = "renesas,iic-r8a73a4", .data = &fast_clock_dt_config }, + { .compatible = "renesas,iic-r8a7740", .data = &r8a7740_dt_config }, + { .compatible = "renesas,iic-r8a774c0", .data = &v2_freq_calc_dt_config }, + { .compatible = "renesas,iic-r8a7790", .data = &v2_freq_calc_dt_config }, + { .compatible = "renesas,iic-r8a7791", .data = &v2_freq_calc_dt_config }, + { .compatible = "renesas,iic-r8a7792", .data = &v2_freq_calc_dt_config }, + { .compatible = "renesas,iic-r8a7793", .data = &v2_freq_calc_dt_config }, + { .compatible = "renesas,iic-r8a7794", .data = &v2_freq_calc_dt_config }, + { .compatible = "renesas,iic-r8a7795", .data = &v2_freq_calc_dt_config }, + { .compatible = "renesas,iic-r8a77990", .data = &v2_freq_calc_dt_config }, + { .compatible = "renesas,iic-sh73a0", .data = &fast_clock_dt_config }, + { .compatible = "renesas,rcar-gen2-iic", .data = &v2_freq_calc_dt_config }, + { .compatible = "renesas,rcar-gen3-iic", .data = &v2_freq_calc_dt_config }, + { .compatible = "renesas,rmobile-iic", .data = &default_dt_config }, + {}, +}; +MODULE_DEVICE_TABLE(of, sh_mobile_i2c_dt_ids); + +static void sh_mobile_i2c_release_dma(struct sh_mobile_i2c_data *pd) +{ + if (!IS_ERR(pd->dma_tx)) { + dma_release_channel(pd->dma_tx); + pd->dma_tx = ERR_PTR(-EPROBE_DEFER); + } + + if (!IS_ERR(pd->dma_rx)) { + dma_release_channel(pd->dma_rx); + pd->dma_rx = ERR_PTR(-EPROBE_DEFER); + } +} + +static int sh_mobile_i2c_hook_irqs(struct platform_device *dev, struct sh_mobile_i2c_data *pd) +{ + struct device_node *np = dev_of_node(&dev->dev); + int k = 0, ret; + + if (np) { + int irq; + + while ((irq = platform_get_irq_optional(dev, k)) != -ENXIO) { + if (irq < 0) + return irq; + ret = devm_request_irq(&dev->dev, irq, sh_mobile_i2c_isr, + 0, dev_name(&dev->dev), pd); + if (ret) { + dev_err(&dev->dev, "cannot request IRQ %d\n", irq); + return ret; + } + k++; + } + } else { + struct resource *res; + resource_size_t n; + + while ((res = platform_get_resource(dev, IORESOURCE_IRQ, k))) { + for (n = res->start; n <= res->end; n++) { + ret = devm_request_irq(&dev->dev, n, sh_mobile_i2c_isr, + 0, dev_name(&dev->dev), pd); + if (ret) { + dev_err(&dev->dev, "cannot request IRQ %pa\n", &n); + return ret; + } + } + k++; + } + } + + return k > 0 ? 0 : -ENOENT; +} + +static int sh_mobile_i2c_probe(struct platform_device *dev) +{ + struct sh_mobile_i2c_data *pd; + struct i2c_adapter *adap; + const struct sh_mobile_dt_config *config; + int ret; + u32 bus_speed; + + pd = devm_kzalloc(&dev->dev, sizeof(struct sh_mobile_i2c_data), GFP_KERNEL); + if (!pd) + return -ENOMEM; + + pd->clk = devm_clk_get(&dev->dev, NULL); + if (IS_ERR(pd->clk)) { + dev_err(&dev->dev, "cannot get clock\n"); + return PTR_ERR(pd->clk); + } + + ret = sh_mobile_i2c_hook_irqs(dev, pd); + if (ret) + return ret; + + pd->dev = &dev->dev; + platform_set_drvdata(dev, pd); + + pd->reg = devm_platform_get_and_ioremap_resource(dev, 0, &pd->res); + if (IS_ERR(pd->reg)) + return PTR_ERR(pd->reg); + + ret = of_property_read_u32(dev->dev.of_node, "clock-frequency", &bus_speed); + pd->bus_speed = (ret || !bus_speed) ? I2C_MAX_STANDARD_MODE_FREQ : bus_speed; + pd->clks_per_count = 1; + + /* Newer variants come with two new bits in ICIC */ + if (resource_size(pd->res) > 0x17) + pd->flags |= IIC_FLAG_HAS_ICIC67; + + pm_runtime_enable(&dev->dev); + pm_runtime_get_sync(&dev->dev); + + config = of_device_get_match_data(&dev->dev); + if (config) { + pd->clks_per_count = config->clks_per_count; + ret = config->setup(pd); + } else { + ret = sh_mobile_i2c_init(pd); + } + + pm_runtime_put_sync(&dev->dev); + if (ret) + return ret; + + /* Init DMA */ + sg_init_table(&pd->sg, 1); + pd->dma_direction = DMA_NONE; + pd->dma_rx = pd->dma_tx = ERR_PTR(-EPROBE_DEFER); + + /* setup the private data */ + adap = &pd->adap; + i2c_set_adapdata(adap, pd); + + adap->owner = THIS_MODULE; + adap->algo = &sh_mobile_i2c_algorithm; + adap->quirks = &sh_mobile_i2c_quirks; + adap->dev.parent = &dev->dev; + adap->retries = 5; + adap->nr = dev->id; + adap->dev.of_node = dev->dev.of_node; + + strscpy(adap->name, dev->name, sizeof(adap->name)); + + spin_lock_init(&pd->lock); + init_waitqueue_head(&pd->wait); + + ret = i2c_add_numbered_adapter(adap); + if (ret < 0) { + sh_mobile_i2c_release_dma(pd); + return ret; + } + + dev_info(&dev->dev, "I2C adapter %d, bus speed %lu Hz\n", adap->nr, pd->bus_speed); + + return 0; +} + +static void sh_mobile_i2c_remove(struct platform_device *dev) +{ + struct sh_mobile_i2c_data *pd = platform_get_drvdata(dev); + + i2c_del_adapter(&pd->adap); + sh_mobile_i2c_release_dma(pd); + pm_runtime_disable(&dev->dev); +} + +static int sh_mobile_i2c_suspend(struct device *dev) +{ + struct sh_mobile_i2c_data *pd = dev_get_drvdata(dev); + + i2c_mark_adapter_suspended(&pd->adap); + return 0; +} + +static int sh_mobile_i2c_resume(struct device *dev) +{ + struct sh_mobile_i2c_data *pd = dev_get_drvdata(dev); + + i2c_mark_adapter_resumed(&pd->adap); + return 0; +} + +static const struct dev_pm_ops sh_mobile_i2c_pm_ops = { + NOIRQ_SYSTEM_SLEEP_PM_OPS(sh_mobile_i2c_suspend, + sh_mobile_i2c_resume) +}; + +static struct platform_driver sh_mobile_i2c_driver = { + .driver = { + .name = "i2c-sh_mobile", + .of_match_table = sh_mobile_i2c_dt_ids, + .pm = pm_sleep_ptr(&sh_mobile_i2c_pm_ops), + }, + .probe = sh_mobile_i2c_probe, + .remove_new = sh_mobile_i2c_remove, +}; + +static int __init sh_mobile_i2c_adap_init(void) +{ + return platform_driver_register(&sh_mobile_i2c_driver); +} +subsys_initcall(sh_mobile_i2c_adap_init); + +static void __exit sh_mobile_i2c_adap_exit(void) +{ + platform_driver_unregister(&sh_mobile_i2c_driver); +} +module_exit(sh_mobile_i2c_adap_exit); + +MODULE_DESCRIPTION("SuperH Mobile I2C Bus Controller driver"); +MODULE_AUTHOR("Magnus Damm"); +MODULE_AUTHOR("Wolfram Sang"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:i2c-sh_mobile"); diff --git a/drivers/i2c/busses/i2c-sibyte.c b/drivers/i2c/busses/i2c-sibyte.c new file mode 100644 index 000000000..8f71f01cb --- /dev/null +++ b/drivers/i2c/busses/i2c-sibyte.c @@ -0,0 +1,186 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2004 Steven J. Hill + * Copyright (C) 2001,2002,2003 Broadcom Corporation + * Copyright (C) 1995-2000 Simon G. Vogl + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/io.h> +#include <asm/sibyte/sb1250_regs.h> +#include <asm/sibyte/sb1250_smbus.h> + + +struct i2c_algo_sibyte_data { + void *data; /* private data */ + int bus; /* which bus */ + void *reg_base; /* CSR base */ +}; + +/* ----- global defines ----------------------------------------------- */ +#define SMB_CSR(a,r) ((long)(a->reg_base + r)) + + +static int smbus_xfer(struct i2c_adapter *i2c_adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data * data) +{ + struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data; + int data_bytes = 0; + int error; + + while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY) + ; + + switch (size) { + case I2C_SMBUS_QUICK: + csr_out32((V_SMB_ADDR(addr) | + (read_write == I2C_SMBUS_READ ? M_SMB_QDATA : 0) | + V_SMB_TT_QUICKCMD), SMB_CSR(adap, R_SMB_START)); + break; + case I2C_SMBUS_BYTE: + if (read_write == I2C_SMBUS_READ) { + csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_RD1BYTE), + SMB_CSR(adap, R_SMB_START)); + data_bytes = 1; + } else { + csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD)); + csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR1BYTE), + SMB_CSR(adap, R_SMB_START)); + } + break; + case I2C_SMBUS_BYTE_DATA: + csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD)); + if (read_write == I2C_SMBUS_READ) { + csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD1BYTE), + SMB_CSR(adap, R_SMB_START)); + data_bytes = 1; + } else { + csr_out32(V_SMB_LB(data->byte), + SMB_CSR(adap, R_SMB_DATA)); + csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE), + SMB_CSR(adap, R_SMB_START)); + } + break; + case I2C_SMBUS_WORD_DATA: + csr_out32(V_SMB_CMD(command), SMB_CSR(adap, R_SMB_CMD)); + if (read_write == I2C_SMBUS_READ) { + csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_CMD_RD2BYTE), + SMB_CSR(adap, R_SMB_START)); + data_bytes = 2; + } else { + csr_out32(V_SMB_LB(data->word & 0xff), + SMB_CSR(adap, R_SMB_DATA)); + csr_out32(V_SMB_MB(data->word >> 8), + SMB_CSR(adap, R_SMB_DATA)); + csr_out32((V_SMB_ADDR(addr) | V_SMB_TT_WR2BYTE), + SMB_CSR(adap, R_SMB_START)); + } + break; + default: + return -EOPNOTSUPP; + } + + while (csr_in32(SMB_CSR(adap, R_SMB_STATUS)) & M_SMB_BUSY) + ; + + error = csr_in32(SMB_CSR(adap, R_SMB_STATUS)); + if (error & M_SMB_ERROR) { + /* Clear error bit by writing a 1 */ + csr_out32(M_SMB_ERROR, SMB_CSR(adap, R_SMB_STATUS)); + return (error & M_SMB_ERROR_TYPE) ? -EIO : -ENXIO; + } + + if (data_bytes == 1) + data->byte = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xff; + if (data_bytes == 2) + data->word = csr_in32(SMB_CSR(adap, R_SMB_DATA)) & 0xffff; + + return 0; +} + +static u32 bit_func(struct i2c_adapter *adap) +{ + return (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA); +} + + +/* -----exported algorithm data: ------------------------------------- */ + +static const struct i2c_algorithm i2c_sibyte_algo = { + .smbus_xfer = smbus_xfer, + .functionality = bit_func, +}; + +/* + * registering functions to load algorithms at runtime + */ +static int __init i2c_sibyte_add_bus(struct i2c_adapter *i2c_adap, int speed) +{ + struct i2c_algo_sibyte_data *adap = i2c_adap->algo_data; + + /* Register new adapter to i2c module... */ + i2c_adap->algo = &i2c_sibyte_algo; + + /* Set the requested frequency. */ + csr_out32(speed, SMB_CSR(adap,R_SMB_FREQ)); + csr_out32(0, SMB_CSR(adap,R_SMB_CONTROL)); + + return i2c_add_numbered_adapter(i2c_adap); +} + + +static struct i2c_algo_sibyte_data sibyte_board_data[2] = { + { NULL, 0, (void *) (CKSEG1+A_SMB_BASE(0)) }, + { NULL, 1, (void *) (CKSEG1+A_SMB_BASE(1)) } +}; + +static struct i2c_adapter sibyte_board_adapter[2] = { + { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = NULL, + .algo_data = &sibyte_board_data[0], + .nr = 0, + .name = "SiByte SMBus 0", + }, + { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = NULL, + .algo_data = &sibyte_board_data[1], + .nr = 1, + .name = "SiByte SMBus 1", + }, +}; + +static int __init i2c_sibyte_init(void) +{ + pr_info("i2c-sibyte: i2c SMBus adapter module for SiByte board\n"); + if (i2c_sibyte_add_bus(&sibyte_board_adapter[0], K_SMB_FREQ_100KHZ) < 0) + return -ENODEV; + if (i2c_sibyte_add_bus(&sibyte_board_adapter[1], + K_SMB_FREQ_400KHZ) < 0) { + i2c_del_adapter(&sibyte_board_adapter[0]); + return -ENODEV; + } + return 0; +} + +static void __exit i2c_sibyte_exit(void) +{ + i2c_del_adapter(&sibyte_board_adapter[0]); + i2c_del_adapter(&sibyte_board_adapter[1]); +} + +module_init(i2c_sibyte_init); +module_exit(i2c_sibyte_exit); + +MODULE_AUTHOR("Kip Walker (Broadcom Corp.)"); +MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com>"); +MODULE_DESCRIPTION("SMBus adapter routines for SiByte boards"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-simtec.c b/drivers/i2c/busses/i2c-simtec.c new file mode 100644 index 000000000..18516bc64 --- /dev/null +++ b/drivers/i2c/busses/i2c-simtec.c @@ -0,0 +1,155 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2005 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * + * Simtec Generic I2C Controller +*/ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/io.h> + +#include <linux/i2c.h> +#include <linux/i2c-algo-bit.h> + +struct simtec_i2c_data { + struct resource *ioarea; + void __iomem *reg; + struct i2c_adapter adap; + struct i2c_algo_bit_data bit; +}; + +#define CMD_SET_SDA (1<<2) +#define CMD_SET_SCL (1<<3) + +#define STATE_SDA (1<<0) +#define STATE_SCL (1<<1) + +/* i2c bit-bus functions */ + +static void simtec_i2c_setsda(void *pw, int state) +{ + struct simtec_i2c_data *pd = pw; + writeb(CMD_SET_SDA | (state ? STATE_SDA : 0), pd->reg); +} + +static void simtec_i2c_setscl(void *pw, int state) +{ + struct simtec_i2c_data *pd = pw; + writeb(CMD_SET_SCL | (state ? STATE_SCL : 0), pd->reg); +} + +static int simtec_i2c_getsda(void *pw) +{ + struct simtec_i2c_data *pd = pw; + return readb(pd->reg) & STATE_SDA ? 1 : 0; +} + +static int simtec_i2c_getscl(void *pw) +{ + struct simtec_i2c_data *pd = pw; + return readb(pd->reg) & STATE_SCL ? 1 : 0; +} + +/* device registration */ + +static int simtec_i2c_probe(struct platform_device *dev) +{ + struct simtec_i2c_data *pd; + struct resource *res; + int size; + int ret; + + pd = kzalloc(sizeof(struct simtec_i2c_data), GFP_KERNEL); + if (pd == NULL) + return -ENOMEM; + + platform_set_drvdata(dev, pd); + + res = platform_get_resource(dev, IORESOURCE_MEM, 0); + if (res == NULL) { + dev_err(&dev->dev, "cannot find IO resource\n"); + ret = -ENOENT; + goto err; + } + + size = resource_size(res); + + pd->ioarea = request_mem_region(res->start, size, dev->name); + if (pd->ioarea == NULL) { + dev_err(&dev->dev, "cannot request IO\n"); + ret = -ENXIO; + goto err; + } + + pd->reg = ioremap(res->start, size); + if (pd->reg == NULL) { + dev_err(&dev->dev, "cannot map IO\n"); + ret = -ENXIO; + goto err_res; + } + + /* setup the private data */ + + pd->adap.owner = THIS_MODULE; + pd->adap.algo_data = &pd->bit; + pd->adap.dev.parent = &dev->dev; + + strscpy(pd->adap.name, "Simtec I2C", sizeof(pd->adap.name)); + + pd->bit.data = pd; + pd->bit.setsda = simtec_i2c_setsda; + pd->bit.setscl = simtec_i2c_setscl; + pd->bit.getsda = simtec_i2c_getsda; + pd->bit.getscl = simtec_i2c_getscl; + pd->bit.timeout = HZ; + pd->bit.udelay = 20; + + ret = i2c_bit_add_bus(&pd->adap); + if (ret) + goto err_all; + + return 0; + + err_all: + iounmap(pd->reg); + + err_res: + release_mem_region(pd->ioarea->start, size); + + err: + kfree(pd); + return ret; +} + +static void simtec_i2c_remove(struct platform_device *dev) +{ + struct simtec_i2c_data *pd = platform_get_drvdata(dev); + + i2c_del_adapter(&pd->adap); + + iounmap(pd->reg); + release_mem_region(pd->ioarea->start, resource_size(pd->ioarea)); + kfree(pd); +} + +/* device driver */ + +static struct platform_driver simtec_i2c_driver = { + .driver = { + .name = "simtec-i2c", + }, + .probe = simtec_i2c_probe, + .remove_new = simtec_i2c_remove, +}; + +module_platform_driver(simtec_i2c_driver); + +MODULE_DESCRIPTION("Simtec Generic I2C Bus driver"); +MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:simtec-i2c"); diff --git a/drivers/i2c/busses/i2c-sis5595.c b/drivers/i2c/busses/i2c-sis5595.c new file mode 100644 index 000000000..486f1e9df --- /dev/null +++ b/drivers/i2c/busses/i2c-sis5595.c @@ -0,0 +1,422 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + Copyright (c) 1998, 1999 Frodo Looijaard <frodol@dds.nl> and + Philip Edelbrock <phil@netroedge.com> + +*/ + +/* Note: we assume there can only be one SIS5595 with one SMBus interface */ + +/* + Note: all have mfr. ID 0x1039. + SUPPORTED PCI ID + 5595 0008 + + Note: these chips contain a 0008 device which is incompatible with the + 5595. We recognize these by the presence of the listed + "blacklist" PCI ID and refuse to load. + + NOT SUPPORTED PCI ID BLACKLIST PCI ID + 540 0008 0540 + 550 0008 0550 + 5513 0008 5511 + 5581 0008 5597 + 5582 0008 5597 + 5597 0008 5597 + 5598 0008 5597/5598 + 630 0008 0630 + 645 0008 0645 + 646 0008 0646 + 648 0008 0648 + 650 0008 0650 + 651 0008 0651 + 730 0008 0730 + 735 0008 0735 + 745 0008 0745 + 746 0008 0746 +*/ + +/* TO DO: + * Add Block Transfers (ugly, but supported by the adapter) + * Add adapter resets + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/pci.h> +#include <linux/ioport.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/acpi.h> +#include <linux/io.h> + +static int blacklist[] = { + PCI_DEVICE_ID_SI_540, + PCI_DEVICE_ID_SI_550, + PCI_DEVICE_ID_SI_630, + PCI_DEVICE_ID_SI_645, + PCI_DEVICE_ID_SI_646, + PCI_DEVICE_ID_SI_648, + PCI_DEVICE_ID_SI_650, + PCI_DEVICE_ID_SI_651, + PCI_DEVICE_ID_SI_730, + PCI_DEVICE_ID_SI_735, + PCI_DEVICE_ID_SI_745, + PCI_DEVICE_ID_SI_746, + PCI_DEVICE_ID_SI_5511, /* 5513 chip has the 0008 device but that ID + shows up in other chips so we use the 5511 + ID for recognition */ + PCI_DEVICE_ID_SI_5597, + PCI_DEVICE_ID_SI_5598, + 0, /* terminates the list */ +}; + +/* Length of ISA address segment */ +#define SIS5595_EXTENT 8 +/* SIS5595 SMBus registers */ +#define SMB_STS_LO 0x00 +#define SMB_STS_HI 0x01 +#define SMB_CTL_LO 0x02 +#define SMB_CTL_HI 0x03 +#define SMB_ADDR 0x04 +#define SMB_CMD 0x05 +#define SMB_PCNT 0x06 +#define SMB_CNT 0x07 +#define SMB_BYTE 0x08 +#define SMB_DEV 0x10 +#define SMB_DB0 0x11 +#define SMB_DB1 0x12 +#define SMB_HAA 0x13 + +/* PCI Address Constants */ +#define SMB_INDEX 0x38 +#define SMB_DAT 0x39 +#define SIS5595_ENABLE_REG 0x40 +#define ACPI_BASE 0x90 + +/* Other settings */ +#define MAX_TIMEOUT 500 + +/* SIS5595 constants */ +#define SIS5595_QUICK 0x00 +#define SIS5595_BYTE 0x02 +#define SIS5595_BYTE_DATA 0x04 +#define SIS5595_WORD_DATA 0x06 +#define SIS5595_PROC_CALL 0x08 +#define SIS5595_BLOCK_DATA 0x0A + +/* insmod parameters */ + +/* If force_addr is set to anything different from 0, we forcibly enable + the device at the given address. */ +static u16 force_addr; +module_param_hw(force_addr, ushort, ioport, 0); +MODULE_PARM_DESC(force_addr, "Initialize the base address of the i2c controller"); + +static struct pci_driver sis5595_driver; +static unsigned short sis5595_base; +static struct pci_dev *sis5595_pdev; + +static u8 sis5595_read(u8 reg) +{ + outb(reg, sis5595_base + SMB_INDEX); + return inb(sis5595_base + SMB_DAT); +} + +static void sis5595_write(u8 reg, u8 data) +{ + outb(reg, sis5595_base + SMB_INDEX); + outb(data, sis5595_base + SMB_DAT); +} + +static int sis5595_setup(struct pci_dev *SIS5595_dev) +{ + u16 a; + u8 val; + int *i; + int retval; + + /* Look for imposters */ + for (i = blacklist; *i != 0; i++) { + struct pci_dev *dev; + dev = pci_get_device(PCI_VENDOR_ID_SI, *i, NULL); + if (dev) { + dev_err(&SIS5595_dev->dev, "Looked for SIS5595 but found unsupported device %.4x\n", *i); + pci_dev_put(dev); + return -ENODEV; + } + } + + /* Determine the address of the SMBus areas */ + pci_read_config_word(SIS5595_dev, ACPI_BASE, &sis5595_base); + if (sis5595_base == 0 && force_addr == 0) { + dev_err(&SIS5595_dev->dev, "ACPI base address uninitialized - upgrade BIOS or use force_addr=0xaddr\n"); + return -ENODEV; + } + + if (force_addr) + sis5595_base = force_addr & ~(SIS5595_EXTENT - 1); + dev_dbg(&SIS5595_dev->dev, "ACPI Base address: %04x\n", sis5595_base); + + /* NB: We grab just the two SMBus registers here, but this may still + * interfere with ACPI :-( */ + retval = acpi_check_region(sis5595_base + SMB_INDEX, 2, + sis5595_driver.name); + if (retval) + return retval; + + if (!request_region(sis5595_base + SMB_INDEX, 2, + sis5595_driver.name)) { + dev_err(&SIS5595_dev->dev, "SMBus registers 0x%04x-0x%04x already in use!\n", + sis5595_base + SMB_INDEX, sis5595_base + SMB_INDEX + 1); + return -ENODEV; + } + + if (force_addr) { + dev_info(&SIS5595_dev->dev, "forcing ISA address 0x%04X\n", sis5595_base); + retval = pci_write_config_word(SIS5595_dev, ACPI_BASE, sis5595_base); + if (retval != PCIBIOS_SUCCESSFUL) + goto error; + retval = pci_read_config_word(SIS5595_dev, ACPI_BASE, &a); + if (retval != PCIBIOS_SUCCESSFUL) + goto error; + if ((a & ~(SIS5595_EXTENT - 1)) != sis5595_base) { + /* doesn't work for some chips! */ + dev_err(&SIS5595_dev->dev, "force address failed - not supported?\n"); + goto error; + } + } + + retval = pci_read_config_byte(SIS5595_dev, SIS5595_ENABLE_REG, &val); + if (retval != PCIBIOS_SUCCESSFUL) + goto error; + if ((val & 0x80) == 0) { + dev_info(&SIS5595_dev->dev, "enabling ACPI\n"); + retval = pci_write_config_byte(SIS5595_dev, SIS5595_ENABLE_REG, val | 0x80); + if (retval != PCIBIOS_SUCCESSFUL) + goto error; + retval = pci_read_config_byte(SIS5595_dev, SIS5595_ENABLE_REG, &val); + if (retval != PCIBIOS_SUCCESSFUL) + goto error; + if ((val & 0x80) == 0) { + /* doesn't work for some chips? */ + dev_err(&SIS5595_dev->dev, "ACPI enable failed - not supported?\n"); + goto error; + } + } + + /* Everything is happy */ + return 0; + +error: + release_region(sis5595_base + SMB_INDEX, 2); + return -ENODEV; +} + +static int sis5595_transaction(struct i2c_adapter *adap) +{ + int temp; + int result = 0; + int timeout = 0; + + /* Make sure the SMBus host is ready to start transmitting */ + temp = sis5595_read(SMB_STS_LO) + (sis5595_read(SMB_STS_HI) << 8); + if (temp != 0x00) { + dev_dbg(&adap->dev, "SMBus busy (%04x). Resetting...\n", temp); + sis5595_write(SMB_STS_LO, temp & 0xff); + sis5595_write(SMB_STS_HI, temp >> 8); + if ((temp = sis5595_read(SMB_STS_LO) + (sis5595_read(SMB_STS_HI) << 8)) != 0x00) { + dev_dbg(&adap->dev, "Failed! (%02x)\n", temp); + return -EBUSY; + } else { + dev_dbg(&adap->dev, "Successful!\n"); + } + } + + /* start the transaction by setting bit 4 */ + sis5595_write(SMB_CTL_LO, sis5595_read(SMB_CTL_LO) | 0x10); + + /* We will always wait for a fraction of a second! */ + do { + msleep(1); + temp = sis5595_read(SMB_STS_LO); + } while (!(temp & 0x40) && (timeout++ < MAX_TIMEOUT)); + + /* If the SMBus is still busy, we give up */ + if (timeout > MAX_TIMEOUT) { + dev_dbg(&adap->dev, "SMBus Timeout!\n"); + result = -ETIMEDOUT; + } + + if (temp & 0x10) { + dev_dbg(&adap->dev, "Error: Failed bus transaction\n"); + result = -ENXIO; + } + + if (temp & 0x20) { + dev_err(&adap->dev, "Bus collision! SMBus may be locked until " + "next hard reset (or not...)\n"); + /* Clock stops and slave is stuck in mid-transmission */ + result = -EIO; + } + + temp = sis5595_read(SMB_STS_LO) + (sis5595_read(SMB_STS_HI) << 8); + if (temp != 0x00) { + sis5595_write(SMB_STS_LO, temp & 0xff); + sis5595_write(SMB_STS_HI, temp >> 8); + } + + temp = sis5595_read(SMB_STS_LO) + (sis5595_read(SMB_STS_HI) << 8); + if (temp != 0x00) + dev_dbg(&adap->dev, "Failed reset at end of transaction (%02x)\n", temp); + + return result; +} + +/* Return negative errno on error. */ +static s32 sis5595_access(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data *data) +{ + int status; + + switch (size) { + case I2C_SMBUS_QUICK: + sis5595_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); + size = SIS5595_QUICK; + break; + case I2C_SMBUS_BYTE: + sis5595_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); + if (read_write == I2C_SMBUS_WRITE) + sis5595_write(SMB_CMD, command); + size = SIS5595_BYTE; + break; + case I2C_SMBUS_BYTE_DATA: + sis5595_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); + sis5595_write(SMB_CMD, command); + if (read_write == I2C_SMBUS_WRITE) + sis5595_write(SMB_BYTE, data->byte); + size = SIS5595_BYTE_DATA; + break; + case I2C_SMBUS_PROC_CALL: + case I2C_SMBUS_WORD_DATA: + sis5595_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); + sis5595_write(SMB_CMD, command); + if (read_write == I2C_SMBUS_WRITE) { + sis5595_write(SMB_BYTE, data->word & 0xff); + sis5595_write(SMB_BYTE + 1, + (data->word & 0xff00) >> 8); + } + size = (size == I2C_SMBUS_PROC_CALL) ? SIS5595_PROC_CALL : SIS5595_WORD_DATA; + break; + default: + dev_warn(&adap->dev, "Unsupported transaction %d\n", size); + return -EOPNOTSUPP; + } + + sis5595_write(SMB_CTL_LO, ((size & 0x0E))); + + status = sis5595_transaction(adap); + if (status) + return status; + + if ((size != SIS5595_PROC_CALL) && + ((read_write == I2C_SMBUS_WRITE) || (size == SIS5595_QUICK))) + return 0; + + + switch (size) { + case SIS5595_BYTE: + case SIS5595_BYTE_DATA: + data->byte = sis5595_read(SMB_BYTE); + break; + case SIS5595_WORD_DATA: + case SIS5595_PROC_CALL: + data->word = sis5595_read(SMB_BYTE) + (sis5595_read(SMB_BYTE + 1) << 8); + break; + } + return 0; +} + +static u32 sis5595_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_PROC_CALL; +} + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = sis5595_access, + .functionality = sis5595_func, +}; + +static struct i2c_adapter sis5595_adapter = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = &smbus_algorithm, +}; + +static const struct pci_device_id sis5595_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_503) }, + { 0, } +}; + +MODULE_DEVICE_TABLE (pci, sis5595_ids); + +static int sis5595_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + int err; + + if (sis5595_setup(dev)) { + dev_err(&dev->dev, "SIS5595 not detected, module not inserted.\n"); + return -ENODEV; + } + + /* set up the sysfs linkage to our parent device */ + sis5595_adapter.dev.parent = &dev->dev; + + snprintf(sis5595_adapter.name, sizeof(sis5595_adapter.name), + "SMBus SIS5595 adapter at %04x", sis5595_base + SMB_INDEX); + err = i2c_add_adapter(&sis5595_adapter); + if (err) { + release_region(sis5595_base + SMB_INDEX, 2); + return err; + } + + /* Always return failure here. This is to allow other drivers to bind + * to this pci device. We don't really want to have control over the + * pci device, we only wanted to read as few register values from it. + */ + sis5595_pdev = pci_dev_get(dev); + return -ENODEV; +} + +static struct pci_driver sis5595_driver = { + .name = "sis5595_smbus", + .id_table = sis5595_ids, + .probe = sis5595_probe, +}; + +static int __init i2c_sis5595_init(void) +{ + return pci_register_driver(&sis5595_driver); +} + +static void __exit i2c_sis5595_exit(void) +{ + pci_unregister_driver(&sis5595_driver); + if (sis5595_pdev) { + i2c_del_adapter(&sis5595_adapter); + release_region(sis5595_base + SMB_INDEX, 2); + pci_dev_put(sis5595_pdev); + sis5595_pdev = NULL; + } +} + +MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>"); +MODULE_DESCRIPTION("SIS5595 SMBus driver"); +MODULE_LICENSE("GPL"); + +module_init(i2c_sis5595_init); +module_exit(i2c_sis5595_exit); diff --git a/drivers/i2c/busses/i2c-sis630.c b/drivers/i2c/busses/i2c-sis630.c new file mode 100644 index 000000000..87d56250d --- /dev/null +++ b/drivers/i2c/busses/i2c-sis630.c @@ -0,0 +1,549 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + Copyright (c) 2002,2003 Alexander Malysh <amalysh@web.de> + +*/ + +/* + Status: beta + + Supports: + SIS 630 + SIS 730 + SIS 964 + + Notable differences between chips: + +------------------------+--------------------+-------------------+ + | | SIS630/730 | SIS964 | + +------------------------+--------------------+-------------------+ + | Clock | 14kHz/56kHz | 55.56kHz/27.78kHz | + | SMBus registers offset | 0x80 | 0xE0 | + | SMB_CNT | Bit 1 = Slave Busy | Bit 1 = Bus probe | + | (not used yet) | Bit 3 is reserved | Bit 3 = Last byte | + | SMB_PCOUNT | Offset + 0x06 | Offset + 0x14 | + | SMB_COUNT | 4:0 bits | 5:0 bits | + +------------------------+--------------------+-------------------+ + (Other differences don't affect the functions provided by the driver) + + Note: we assume there can only be one device, with one SMBus interface. +*/ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/pci.h> +#include <linux/ioport.h> +#include <linux/i2c.h> +#include <linux/acpi.h> +#include <linux/io.h> + +/* SIS964 id is defined here as we are the only file using it */ +#define PCI_DEVICE_ID_SI_964 0x0964 + +/* SIS630/730/964 SMBus registers */ +#define SMB_STS 0x00 /* status */ +#define SMB_CNT 0x02 /* control */ +#define SMBHOST_CNT 0x03 /* host control */ +#define SMB_ADDR 0x04 /* address */ +#define SMB_CMD 0x05 /* command */ +#define SMB_COUNT 0x07 /* byte count */ +#define SMB_BYTE 0x08 /* ~0x8F data byte field */ + +/* SMB_STS register */ +#define BYTE_DONE_STS 0x10 /* Byte Done Status / Block Array */ +#define SMBCOL_STS 0x04 /* Collision */ +#define SMBERR_STS 0x02 /* Device error */ + +/* SMB_CNT register */ +#define MSTO_EN 0x40 /* Host Master Timeout Enable */ +#define SMBCLK_SEL 0x20 /* Host master clock selection */ +#define SMB_PROBE 0x02 /* Bus Probe/Slave busy */ +#define SMB_HOSTBUSY 0x01 /* Host Busy */ + +/* SMBHOST_CNT register */ +#define SMB_KILL 0x20 /* Kill */ +#define SMB_START 0x10 /* Start */ + +/* register count for request_region + * As we don't use SMB_PCOUNT, 20 is ok for SiS630 and SiS964 + */ +#define SIS630_SMB_IOREGION 20 + +/* PCI address constants */ +/* acpi base address register */ +#define SIS630_ACPI_BASE_REG 0x74 +/* bios control register */ +#define SIS630_BIOS_CTL_REG 0x40 + +/* Other settings */ +#define MAX_TIMEOUT 500 + +/* SIS630 constants */ +#define SIS630_QUICK 0x00 +#define SIS630_BYTE 0x01 +#define SIS630_BYTE_DATA 0x02 +#define SIS630_WORD_DATA 0x03 +#define SIS630_PCALL 0x04 +#define SIS630_BLOCK_DATA 0x05 + +static struct pci_driver sis630_driver; + +/* insmod parameters */ +static bool high_clock; +static bool force; +module_param(high_clock, bool, 0); +MODULE_PARM_DESC(high_clock, + "Set Host Master Clock to 56KHz (default 14KHz) (SIS630/730 only)."); +module_param(force, bool, 0); +MODULE_PARM_DESC(force, "Forcibly enable the SIS630. DANGEROUS!"); + +/* SMBus base address */ +static unsigned short smbus_base; + +/* supported chips */ +static int supported[] = { + PCI_DEVICE_ID_SI_630, + PCI_DEVICE_ID_SI_730, + PCI_DEVICE_ID_SI_760, + 0 /* terminates the list */ +}; + +static inline u8 sis630_read(u8 reg) +{ + return inb(smbus_base + reg); +} + +static inline void sis630_write(u8 reg, u8 data) +{ + outb(data, smbus_base + reg); +} + +static int sis630_transaction_start(struct i2c_adapter *adap, int size, + u8 *oldclock) +{ + int temp; + + /* Make sure the SMBus host is ready to start transmitting. */ + temp = sis630_read(SMB_CNT); + if ((temp & (SMB_PROBE | SMB_HOSTBUSY)) != 0x00) { + dev_dbg(&adap->dev, "SMBus busy (%02x). Resetting...\n", temp); + /* kill smbus transaction */ + sis630_write(SMBHOST_CNT, SMB_KILL); + + temp = sis630_read(SMB_CNT); + if (temp & (SMB_PROBE | SMB_HOSTBUSY)) { + dev_dbg(&adap->dev, "Failed! (%02x)\n", temp); + return -EBUSY; + } else { + dev_dbg(&adap->dev, "Successful!\n"); + } + } + + /* save old clock, so we can prevent machine for hung */ + *oldclock = sis630_read(SMB_CNT); + + dev_dbg(&adap->dev, "saved clock 0x%02x\n", *oldclock); + + /* disable timeout interrupt, + * set Host Master Clock to 56KHz if requested */ + if (high_clock) + sis630_write(SMB_CNT, SMBCLK_SEL); + else + sis630_write(SMB_CNT, (*oldclock & ~MSTO_EN)); + + /* clear all sticky bits */ + temp = sis630_read(SMB_STS); + sis630_write(SMB_STS, temp & 0x1e); + + /* start the transaction by setting bit 4 and size */ + sis630_write(SMBHOST_CNT, SMB_START | (size & 0x07)); + + return 0; +} + +static int sis630_transaction_wait(struct i2c_adapter *adap, int size) +{ + int temp, result = 0, timeout = 0; + + /* We will always wait for a fraction of a second! */ + do { + msleep(1); + temp = sis630_read(SMB_STS); + /* check if block transmitted */ + if (size == SIS630_BLOCK_DATA && (temp & BYTE_DONE_STS)) + break; + } while (!(temp & 0x0e) && (timeout++ < MAX_TIMEOUT)); + + /* If the SMBus is still busy, we give up */ + if (timeout > MAX_TIMEOUT) { + dev_dbg(&adap->dev, "SMBus Timeout!\n"); + result = -ETIMEDOUT; + } + + if (temp & SMBERR_STS) { + dev_dbg(&adap->dev, "Error: Failed bus transaction\n"); + result = -ENXIO; + } + + if (temp & SMBCOL_STS) { + dev_err(&adap->dev, "Bus collision!\n"); + result = -EAGAIN; + } + + return result; +} + +static void sis630_transaction_end(struct i2c_adapter *adap, u8 oldclock) +{ + /* clear all status "sticky" bits */ + sis630_write(SMB_STS, 0xFF); + + dev_dbg(&adap->dev, + "SMB_CNT before clock restore 0x%02x\n", sis630_read(SMB_CNT)); + + /* + * restore old Host Master Clock if high_clock is set + * and oldclock was not 56KHz + */ + if (high_clock && !(oldclock & SMBCLK_SEL)) + sis630_write(SMB_CNT, sis630_read(SMB_CNT) & ~SMBCLK_SEL); + + dev_dbg(&adap->dev, + "SMB_CNT after clock restore 0x%02x\n", sis630_read(SMB_CNT)); +} + +static int sis630_transaction(struct i2c_adapter *adap, int size) +{ + int result = 0; + u8 oldclock = 0; + + result = sis630_transaction_start(adap, size, &oldclock); + if (!result) { + result = sis630_transaction_wait(adap, size); + sis630_transaction_end(adap, oldclock); + } + + return result; +} + +static int sis630_block_data(struct i2c_adapter *adap, + union i2c_smbus_data *data, int read_write) +{ + int i, len = 0, rc = 0; + u8 oldclock = 0; + + if (read_write == I2C_SMBUS_WRITE) { + len = data->block[0]; + if (len < 0) + len = 0; + else if (len > 32) + len = 32; + sis630_write(SMB_COUNT, len); + for (i = 1; i <= len; i++) { + dev_dbg(&adap->dev, + "set data 0x%02x\n", data->block[i]); + /* set data */ + sis630_write(SMB_BYTE + (i - 1) % 8, data->block[i]); + if (i == 8 || (len < 8 && i == len)) { + dev_dbg(&adap->dev, + "start trans len=%d i=%d\n", len, i); + /* first transaction */ + rc = sis630_transaction_start(adap, + SIS630_BLOCK_DATA, &oldclock); + if (rc) + return rc; + } else if ((i - 1) % 8 == 7 || i == len) { + dev_dbg(&adap->dev, + "trans_wait len=%d i=%d\n", len, i); + if (i > 8) { + dev_dbg(&adap->dev, + "clear smbary_sts" + " len=%d i=%d\n", len, i); + /* + If this is not first transaction, + we must clear sticky bit. + clear SMBARY_STS + */ + sis630_write(SMB_STS, BYTE_DONE_STS); + } + rc = sis630_transaction_wait(adap, + SIS630_BLOCK_DATA); + if (rc) { + dev_dbg(&adap->dev, + "trans_wait failed\n"); + break; + } + } + } + } else { + /* read request */ + data->block[0] = len = 0; + rc = sis630_transaction_start(adap, + SIS630_BLOCK_DATA, &oldclock); + if (rc) + return rc; + do { + rc = sis630_transaction_wait(adap, SIS630_BLOCK_DATA); + if (rc) { + dev_dbg(&adap->dev, "trans_wait failed\n"); + break; + } + /* if this first transaction then read byte count */ + if (len == 0) + data->block[0] = sis630_read(SMB_COUNT); + + /* just to be sure */ + if (data->block[0] > 32) + data->block[0] = 32; + + dev_dbg(&adap->dev, + "block data read len=0x%x\n", data->block[0]); + + for (i = 0; i < 8 && len < data->block[0]; i++, len++) { + dev_dbg(&adap->dev, + "read i=%d len=%d\n", i, len); + data->block[len + 1] = sis630_read(SMB_BYTE + + i); + } + + dev_dbg(&adap->dev, + "clear smbary_sts len=%d i=%d\n", len, i); + + /* clear SMBARY_STS */ + sis630_write(SMB_STS, BYTE_DONE_STS); + } while (len < data->block[0]); + } + + sis630_transaction_end(adap, oldclock); + + return rc; +} + +/* Return negative errno on error. */ +static s32 sis630_access(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data *data) +{ + int status; + + switch (size) { + case I2C_SMBUS_QUICK: + sis630_write(SMB_ADDR, + ((addr & 0x7f) << 1) | (read_write & 0x01)); + size = SIS630_QUICK; + break; + case I2C_SMBUS_BYTE: + sis630_write(SMB_ADDR, + ((addr & 0x7f) << 1) | (read_write & 0x01)); + if (read_write == I2C_SMBUS_WRITE) + sis630_write(SMB_CMD, command); + size = SIS630_BYTE; + break; + case I2C_SMBUS_BYTE_DATA: + sis630_write(SMB_ADDR, + ((addr & 0x7f) << 1) | (read_write & 0x01)); + sis630_write(SMB_CMD, command); + if (read_write == I2C_SMBUS_WRITE) + sis630_write(SMB_BYTE, data->byte); + size = SIS630_BYTE_DATA; + break; + case I2C_SMBUS_PROC_CALL: + case I2C_SMBUS_WORD_DATA: + sis630_write(SMB_ADDR, + ((addr & 0x7f) << 1) | (read_write & 0x01)); + sis630_write(SMB_CMD, command); + if (read_write == I2C_SMBUS_WRITE) { + sis630_write(SMB_BYTE, data->word & 0xff); + sis630_write(SMB_BYTE + 1, (data->word & 0xff00) >> 8); + } + size = (size == I2C_SMBUS_PROC_CALL ? + SIS630_PCALL : SIS630_WORD_DATA); + break; + case I2C_SMBUS_BLOCK_DATA: + sis630_write(SMB_ADDR, + ((addr & 0x7f) << 1) | (read_write & 0x01)); + sis630_write(SMB_CMD, command); + size = SIS630_BLOCK_DATA; + return sis630_block_data(adap, data, read_write); + default: + dev_warn(&adap->dev, "Unsupported transaction %d\n", size); + return -EOPNOTSUPP; + } + + status = sis630_transaction(adap, size); + if (status) + return status; + + if ((size != SIS630_PCALL) && + ((read_write == I2C_SMBUS_WRITE) || (size == SIS630_QUICK))) { + return 0; + } + + switch (size) { + case SIS630_BYTE: + case SIS630_BYTE_DATA: + data->byte = sis630_read(SMB_BYTE); + break; + case SIS630_PCALL: + case SIS630_WORD_DATA: + data->word = sis630_read(SMB_BYTE) + + (sis630_read(SMB_BYTE + 1) << 8); + break; + } + + return 0; +} + +static u32 sis630_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_BLOCK_DATA; +} + +static int sis630_setup(struct pci_dev *sis630_dev) +{ + unsigned char b; + struct pci_dev *dummy = NULL; + int retval, i; + /* acpi base address */ + unsigned short acpi_base; + + /* check for supported SiS devices */ + for (i = 0; supported[i] > 0; i++) { + dummy = pci_get_device(PCI_VENDOR_ID_SI, supported[i], dummy); + if (dummy) + break; /* found */ + } + + if (dummy) { + pci_dev_put(dummy); + } else if (force) { + dev_err(&sis630_dev->dev, + "WARNING: Can't detect SIS630 compatible device, but " + "loading because of force option enabled\n"); + } else { + return -ENODEV; + } + + /* + Enable ACPI first , so we can accsess reg 74-75 + in acpi io space and read acpi base addr + */ + if (pci_read_config_byte(sis630_dev, SIS630_BIOS_CTL_REG, &b)) { + dev_err(&sis630_dev->dev, "Error: Can't read bios ctl reg\n"); + retval = -ENODEV; + goto exit; + } + /* if ACPI already enabled , do nothing */ + if (!(b & 0x80) && + pci_write_config_byte(sis630_dev, SIS630_BIOS_CTL_REG, b | 0x80)) { + dev_err(&sis630_dev->dev, "Error: Can't enable ACPI\n"); + retval = -ENODEV; + goto exit; + } + + /* Determine the ACPI base address */ + if (pci_read_config_word(sis630_dev, + SIS630_ACPI_BASE_REG, &acpi_base)) { + dev_err(&sis630_dev->dev, + "Error: Can't determine ACPI base address\n"); + retval = -ENODEV; + goto exit; + } + + dev_dbg(&sis630_dev->dev, "ACPI base at 0x%04hx\n", acpi_base); + + if (supported[i] == PCI_DEVICE_ID_SI_760) + smbus_base = acpi_base + 0xE0; + else + smbus_base = acpi_base + 0x80; + + dev_dbg(&sis630_dev->dev, "SMBus base at 0x%04hx\n", smbus_base); + + retval = acpi_check_region(smbus_base + SMB_STS, SIS630_SMB_IOREGION, + sis630_driver.name); + if (retval) + goto exit; + + /* Everything is happy, let's grab the memory and set things up. */ + if (!request_region(smbus_base + SMB_STS, SIS630_SMB_IOREGION, + sis630_driver.name)) { + dev_err(&sis630_dev->dev, + "I/O Region 0x%04x-0x%04x for SMBus already in use.\n", + smbus_base + SMB_STS, + smbus_base + SMB_STS + SIS630_SMB_IOREGION - 1); + retval = -EBUSY; + goto exit; + } + + retval = 0; + +exit: + if (retval) + smbus_base = 0; + return retval; +} + + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = sis630_access, + .functionality = sis630_func, +}; + +static struct i2c_adapter sis630_adapter = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = &smbus_algorithm, + .retries = 3 +}; + +static const struct pci_device_id sis630_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_503) }, + { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_LPC) }, + { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_964) }, + { 0, } +}; + +MODULE_DEVICE_TABLE(pci, sis630_ids); + +static int sis630_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + if (sis630_setup(dev)) { + dev_err(&dev->dev, + "SIS630 compatible bus not detected, " + "module not inserted.\n"); + return -ENODEV; + } + + /* set up the sysfs linkage to our parent device */ + sis630_adapter.dev.parent = &dev->dev; + + snprintf(sis630_adapter.name, sizeof(sis630_adapter.name), + "SMBus SIS630 adapter at %04x", smbus_base + SMB_STS); + + return i2c_add_adapter(&sis630_adapter); +} + +static void sis630_remove(struct pci_dev *dev) +{ + if (smbus_base) { + i2c_del_adapter(&sis630_adapter); + release_region(smbus_base + SMB_STS, SIS630_SMB_IOREGION); + smbus_base = 0; + } +} + + +static struct pci_driver sis630_driver = { + .name = "sis630_smbus", + .id_table = sis630_ids, + .probe = sis630_probe, + .remove = sis630_remove, +}; + +module_pci_driver(sis630_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Alexander Malysh <amalysh@web.de>"); +MODULE_DESCRIPTION("SIS630 SMBus driver"); diff --git a/drivers/i2c/busses/i2c-sis96x.c b/drivers/i2c/busses/i2c-sis96x.c new file mode 100644 index 000000000..cde800398 --- /dev/null +++ b/drivers/i2c/busses/i2c-sis96x.c @@ -0,0 +1,318 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + Copyright (c) 2003 Mark M. Hoffman <mhoffman@lightlink.com> + +*/ + +/* + This module must be considered BETA unless and until + the chipset manufacturer releases a datasheet. + The register definitions are based on the SiS630. + + This module relies on quirk_sis_96x_smbus (drivers/pci/quirks.c) + for just about every machine for which users have reported. + If this module isn't detecting your 96x south bridge, have a + look there. + + We assume there can only be one SiS96x with one SMBus interface. +*/ + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/stddef.h> +#include <linux/ioport.h> +#include <linux/i2c.h> +#include <linux/acpi.h> +#include <linux/io.h> + +/* base address register in PCI config space */ +#define SIS96x_BAR 0x04 + +/* SiS96x SMBus registers */ +#define SMB_STS 0x00 +#define SMB_EN 0x01 +#define SMB_CNT 0x02 +#define SMB_HOST_CNT 0x03 +#define SMB_ADDR 0x04 +#define SMB_CMD 0x05 +#define SMB_PCOUNT 0x06 +#define SMB_COUNT 0x07 +#define SMB_BYTE 0x08 +#define SMB_DEV_ADDR 0x10 +#define SMB_DB0 0x11 +#define SMB_DB1 0x12 +#define SMB_SAA 0x13 + +/* register count for request_region */ +#define SMB_IOSIZE 0x20 + +/* Other settings */ +#define MAX_TIMEOUT 500 + +/* SiS96x SMBus constants */ +#define SIS96x_QUICK 0x00 +#define SIS96x_BYTE 0x01 +#define SIS96x_BYTE_DATA 0x02 +#define SIS96x_WORD_DATA 0x03 +#define SIS96x_PROC_CALL 0x04 +#define SIS96x_BLOCK_DATA 0x05 + +static struct pci_driver sis96x_driver; +static struct i2c_adapter sis96x_adapter; +static u16 sis96x_smbus_base; + +static inline u8 sis96x_read(u8 reg) +{ + return inb(sis96x_smbus_base + reg) ; +} + +static inline void sis96x_write(u8 reg, u8 data) +{ + outb(data, sis96x_smbus_base + reg) ; +} + +/* Execute a SMBus transaction. + int size is from SIS96x_QUICK to SIS96x_BLOCK_DATA + */ +static int sis96x_transaction(int size) +{ + int temp; + int result = 0; + int timeout = 0; + + dev_dbg(&sis96x_adapter.dev, "SMBus transaction %d\n", size); + + /* Make sure the SMBus host is ready to start transmitting */ + if (((temp = sis96x_read(SMB_CNT)) & 0x03) != 0x00) { + + dev_dbg(&sis96x_adapter.dev, "SMBus busy (0x%02x). " + "Resetting...\n", temp); + + /* kill the transaction */ + sis96x_write(SMB_HOST_CNT, 0x20); + + /* check it again */ + if (((temp = sis96x_read(SMB_CNT)) & 0x03) != 0x00) { + dev_dbg(&sis96x_adapter.dev, "Failed (0x%02x)\n", temp); + return -EBUSY; + } else { + dev_dbg(&sis96x_adapter.dev, "Successful\n"); + } + } + + /* Turn off timeout interrupts, set fast host clock */ + sis96x_write(SMB_CNT, 0x20); + + /* clear all (sticky) status flags */ + temp = sis96x_read(SMB_STS); + sis96x_write(SMB_STS, temp & 0x1e); + + /* start the transaction by setting bit 4 and size bits */ + sis96x_write(SMB_HOST_CNT, 0x10 | (size & 0x07)); + + /* We will always wait for a fraction of a second! */ + do { + msleep(1); + temp = sis96x_read(SMB_STS); + } while (!(temp & 0x0e) && (timeout++ < MAX_TIMEOUT)); + + /* If the SMBus is still busy, we give up */ + if (timeout > MAX_TIMEOUT) { + dev_dbg(&sis96x_adapter.dev, "SMBus Timeout! (0x%02x)\n", temp); + result = -ETIMEDOUT; + } + + /* device error - probably missing ACK */ + if (temp & 0x02) { + dev_dbg(&sis96x_adapter.dev, "Failed bus transaction!\n"); + result = -ENXIO; + } + + /* bus collision */ + if (temp & 0x04) { + dev_dbg(&sis96x_adapter.dev, "Bus collision!\n"); + result = -EIO; + } + + /* Finish up by resetting the bus */ + sis96x_write(SMB_STS, temp); + if ((temp = sis96x_read(SMB_STS))) { + dev_dbg(&sis96x_adapter.dev, "Failed reset at " + "end of transaction! (0x%02x)\n", temp); + } + + return result; +} + +/* Return negative errno on error. */ +static s32 sis96x_access(struct i2c_adapter * adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data * data) +{ + int status; + + switch (size) { + case I2C_SMBUS_QUICK: + sis96x_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); + size = SIS96x_QUICK; + break; + + case I2C_SMBUS_BYTE: + sis96x_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); + if (read_write == I2C_SMBUS_WRITE) + sis96x_write(SMB_CMD, command); + size = SIS96x_BYTE; + break; + + case I2C_SMBUS_BYTE_DATA: + sis96x_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); + sis96x_write(SMB_CMD, command); + if (read_write == I2C_SMBUS_WRITE) + sis96x_write(SMB_BYTE, data->byte); + size = SIS96x_BYTE_DATA; + break; + + case I2C_SMBUS_PROC_CALL: + case I2C_SMBUS_WORD_DATA: + sis96x_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); + sis96x_write(SMB_CMD, command); + if (read_write == I2C_SMBUS_WRITE) { + sis96x_write(SMB_BYTE, data->word & 0xff); + sis96x_write(SMB_BYTE + 1, (data->word & 0xff00) >> 8); + } + size = (size == I2C_SMBUS_PROC_CALL ? + SIS96x_PROC_CALL : SIS96x_WORD_DATA); + break; + + default: + dev_warn(&adap->dev, "Unsupported transaction %d\n", size); + return -EOPNOTSUPP; + } + + status = sis96x_transaction(size); + if (status) + return status; + + if ((size != SIS96x_PROC_CALL) && + ((read_write == I2C_SMBUS_WRITE) || (size == SIS96x_QUICK))) + return 0; + + switch (size) { + case SIS96x_BYTE: + case SIS96x_BYTE_DATA: + data->byte = sis96x_read(SMB_BYTE); + break; + + case SIS96x_WORD_DATA: + case SIS96x_PROC_CALL: + data->word = sis96x_read(SMB_BYTE) + + (sis96x_read(SMB_BYTE + 1) << 8); + break; + } + return 0; +} + +static u32 sis96x_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_PROC_CALL; +} + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = sis96x_access, + .functionality = sis96x_func, +}; + +static struct i2c_adapter sis96x_adapter = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = &smbus_algorithm, +}; + +static const struct pci_device_id sis96x_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_SMBUS) }, + { 0, } +}; + +MODULE_DEVICE_TABLE (pci, sis96x_ids); + +static int sis96x_probe(struct pci_dev *dev, + const struct pci_device_id *id) +{ + u16 ww = 0; + int retval; + + if (sis96x_smbus_base) { + dev_err(&dev->dev, "Only one device supported.\n"); + return -EBUSY; + } + + pci_read_config_word(dev, PCI_CLASS_DEVICE, &ww); + if (PCI_CLASS_SERIAL_SMBUS != ww) { + dev_err(&dev->dev, "Unsupported device class 0x%04x!\n", ww); + return -ENODEV; + } + + sis96x_smbus_base = pci_resource_start(dev, SIS96x_BAR); + if (!sis96x_smbus_base) { + dev_err(&dev->dev, "SiS96x SMBus base address " + "not initialized!\n"); + return -EINVAL; + } + dev_info(&dev->dev, "SiS96x SMBus base address: 0x%04x\n", + sis96x_smbus_base); + + retval = acpi_check_resource_conflict(&dev->resource[SIS96x_BAR]); + if (retval) + return -ENODEV; + + /* Everything is happy, let's grab the memory and set things up. */ + if (!request_region(sis96x_smbus_base, SMB_IOSIZE, + sis96x_driver.name)) { + dev_err(&dev->dev, "SMBus registers 0x%04x-0x%04x " + "already in use!\n", sis96x_smbus_base, + sis96x_smbus_base + SMB_IOSIZE - 1); + + sis96x_smbus_base = 0; + return -EINVAL; + } + + /* set up the sysfs linkage to our parent device */ + sis96x_adapter.dev.parent = &dev->dev; + + snprintf(sis96x_adapter.name, sizeof(sis96x_adapter.name), + "SiS96x SMBus adapter at 0x%04x", sis96x_smbus_base); + + if ((retval = i2c_add_adapter(&sis96x_adapter))) { + dev_err(&dev->dev, "Couldn't register adapter!\n"); + release_region(sis96x_smbus_base, SMB_IOSIZE); + sis96x_smbus_base = 0; + } + + return retval; +} + +static void sis96x_remove(struct pci_dev *dev) +{ + if (sis96x_smbus_base) { + i2c_del_adapter(&sis96x_adapter); + release_region(sis96x_smbus_base, SMB_IOSIZE); + sis96x_smbus_base = 0; + } +} + +static struct pci_driver sis96x_driver = { + .name = "sis96x_smbus", + .id_table = sis96x_ids, + .probe = sis96x_probe, + .remove = sis96x_remove, +}; + +module_pci_driver(sis96x_driver); + +MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>"); +MODULE_DESCRIPTION("SiS96x SMBus driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-sprd.c b/drivers/i2c/busses/i2c-sprd.c new file mode 100644 index 000000000..c52d1bec6 --- /dev/null +++ b/drivers/i2c/busses/i2c-sprd.c @@ -0,0 +1,659 @@ +/* + * Copyright (C) 2017 Spreadtrum Communications Inc. + * + * SPDX-License-Identifier: (GPL-2.0+ OR MIT) + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> + +#define I2C_CTL 0x00 +#define I2C_ADDR_CFG 0x04 +#define I2C_COUNT 0x08 +#define I2C_RX 0x0c +#define I2C_TX 0x10 +#define I2C_STATUS 0x14 +#define I2C_HSMODE_CFG 0x18 +#define I2C_VERSION 0x1c +#define ADDR_DVD0 0x20 +#define ADDR_DVD1 0x24 +#define ADDR_STA0_DVD 0x28 +#define ADDR_RST 0x2c + +/* I2C_CTL */ +#define STP_EN BIT(20) +#define FIFO_AF_LVL_MASK GENMASK(19, 16) +#define FIFO_AF_LVL 16 +#define FIFO_AE_LVL_MASK GENMASK(15, 12) +#define FIFO_AE_LVL 12 +#define I2C_DMA_EN BIT(11) +#define FULL_INTEN BIT(10) +#define EMPTY_INTEN BIT(9) +#define I2C_DVD_OPT BIT(8) +#define I2C_OUT_OPT BIT(7) +#define I2C_TRIM_OPT BIT(6) +#define I2C_HS_MODE BIT(4) +#define I2C_MODE BIT(3) +#define I2C_EN BIT(2) +#define I2C_INT_EN BIT(1) +#define I2C_START BIT(0) + +/* I2C_STATUS */ +#define SDA_IN BIT(21) +#define SCL_IN BIT(20) +#define FIFO_FULL BIT(4) +#define FIFO_EMPTY BIT(3) +#define I2C_INT BIT(2) +#define I2C_RX_ACK BIT(1) +#define I2C_BUSY BIT(0) + +/* ADDR_RST */ +#define I2C_RST BIT(0) + +#define I2C_FIFO_DEEP 12 +#define I2C_FIFO_FULL_THLD 15 +#define I2C_FIFO_EMPTY_THLD 4 +#define I2C_DATA_STEP 8 +#define I2C_ADDR_DVD0_CALC(high, low) \ + ((((high) & GENMASK(15, 0)) << 16) | ((low) & GENMASK(15, 0))) +#define I2C_ADDR_DVD1_CALC(high, low) \ + (((high) & GENMASK(31, 16)) | (((low) & GENMASK(31, 16)) >> 16)) + +/* timeout (ms) for pm runtime autosuspend */ +#define SPRD_I2C_PM_TIMEOUT 1000 +/* timeout (ms) for transfer message */ +#define I2C_XFER_TIMEOUT 1000 + +/* SPRD i2c data structure */ +struct sprd_i2c { + struct i2c_adapter adap; + struct device *dev; + void __iomem *base; + struct i2c_msg *msg; + struct clk *clk; + u32 src_clk; + u32 bus_freq; + struct completion complete; + u8 *buf; + u32 count; + int irq; + int err; +}; + +static void sprd_i2c_set_count(struct sprd_i2c *i2c_dev, u32 count) +{ + writel(count, i2c_dev->base + I2C_COUNT); +} + +static void sprd_i2c_send_stop(struct sprd_i2c *i2c_dev, int stop) +{ + u32 tmp = readl(i2c_dev->base + I2C_CTL); + + if (stop) + writel(tmp & ~STP_EN, i2c_dev->base + I2C_CTL); + else + writel(tmp | STP_EN, i2c_dev->base + I2C_CTL); +} + +static void sprd_i2c_clear_start(struct sprd_i2c *i2c_dev) +{ + u32 tmp = readl(i2c_dev->base + I2C_CTL); + + writel(tmp & ~I2C_START, i2c_dev->base + I2C_CTL); +} + +static void sprd_i2c_clear_ack(struct sprd_i2c *i2c_dev) +{ + u32 tmp = readl(i2c_dev->base + I2C_STATUS); + + writel(tmp & ~I2C_RX_ACK, i2c_dev->base + I2C_STATUS); +} + +static void sprd_i2c_clear_irq(struct sprd_i2c *i2c_dev) +{ + u32 tmp = readl(i2c_dev->base + I2C_STATUS); + + writel(tmp & ~I2C_INT, i2c_dev->base + I2C_STATUS); +} + +static void sprd_i2c_reset_fifo(struct sprd_i2c *i2c_dev) +{ + writel(I2C_RST, i2c_dev->base + ADDR_RST); +} + +static void sprd_i2c_set_devaddr(struct sprd_i2c *i2c_dev, struct i2c_msg *m) +{ + writel(m->addr << 1, i2c_dev->base + I2C_ADDR_CFG); +} + +static void sprd_i2c_write_bytes(struct sprd_i2c *i2c_dev, u8 *buf, u32 len) +{ + u32 i; + + for (i = 0; i < len; i++) + writeb(buf[i], i2c_dev->base + I2C_TX); +} + +static void sprd_i2c_read_bytes(struct sprd_i2c *i2c_dev, u8 *buf, u32 len) +{ + u32 i; + + for (i = 0; i < len; i++) + buf[i] = readb(i2c_dev->base + I2C_RX); +} + +static void sprd_i2c_set_full_thld(struct sprd_i2c *i2c_dev, u32 full_thld) +{ + u32 tmp = readl(i2c_dev->base + I2C_CTL); + + tmp &= ~FIFO_AF_LVL_MASK; + tmp |= full_thld << FIFO_AF_LVL; + writel(tmp, i2c_dev->base + I2C_CTL); +}; + +static void sprd_i2c_set_empty_thld(struct sprd_i2c *i2c_dev, u32 empty_thld) +{ + u32 tmp = readl(i2c_dev->base + I2C_CTL); + + tmp &= ~FIFO_AE_LVL_MASK; + tmp |= empty_thld << FIFO_AE_LVL; + writel(tmp, i2c_dev->base + I2C_CTL); +}; + +static void sprd_i2c_set_fifo_full_int(struct sprd_i2c *i2c_dev, int enable) +{ + u32 tmp = readl(i2c_dev->base + I2C_CTL); + + if (enable) + tmp |= FULL_INTEN; + else + tmp &= ~FULL_INTEN; + + writel(tmp, i2c_dev->base + I2C_CTL); +}; + +static void sprd_i2c_set_fifo_empty_int(struct sprd_i2c *i2c_dev, int enable) +{ + u32 tmp = readl(i2c_dev->base + I2C_CTL); + + if (enable) + tmp |= EMPTY_INTEN; + else + tmp &= ~EMPTY_INTEN; + + writel(tmp, i2c_dev->base + I2C_CTL); +}; + +static void sprd_i2c_opt_start(struct sprd_i2c *i2c_dev) +{ + u32 tmp = readl(i2c_dev->base + I2C_CTL); + + writel(tmp | I2C_START, i2c_dev->base + I2C_CTL); +} + +static void sprd_i2c_opt_mode(struct sprd_i2c *i2c_dev, int rw) +{ + u32 cmd = readl(i2c_dev->base + I2C_CTL) & ~I2C_MODE; + + writel(cmd | rw << 3, i2c_dev->base + I2C_CTL); +} + +static void sprd_i2c_data_transfer(struct sprd_i2c *i2c_dev) +{ + u32 i2c_count = i2c_dev->count; + u32 need_tran = i2c_count <= I2C_FIFO_DEEP ? i2c_count : I2C_FIFO_DEEP; + struct i2c_msg *msg = i2c_dev->msg; + + if (msg->flags & I2C_M_RD) { + sprd_i2c_read_bytes(i2c_dev, i2c_dev->buf, I2C_FIFO_FULL_THLD); + i2c_dev->count -= I2C_FIFO_FULL_THLD; + i2c_dev->buf += I2C_FIFO_FULL_THLD; + + /* + * If the read data count is larger than rx fifo full threshold, + * we should enable the rx fifo full interrupt to read data + * again. + */ + if (i2c_dev->count >= I2C_FIFO_FULL_THLD) + sprd_i2c_set_fifo_full_int(i2c_dev, 1); + } else { + sprd_i2c_write_bytes(i2c_dev, i2c_dev->buf, need_tran); + i2c_dev->buf += need_tran; + i2c_dev->count -= need_tran; + + /* + * If the write data count is arger than tx fifo depth which + * means we can not write all data in one time, then we should + * enable the tx fifo empty interrupt to write again. + */ + if (i2c_count > I2C_FIFO_DEEP) + sprd_i2c_set_fifo_empty_int(i2c_dev, 1); + } +} + +static int sprd_i2c_handle_msg(struct i2c_adapter *i2c_adap, + struct i2c_msg *msg, bool is_last_msg) +{ + struct sprd_i2c *i2c_dev = i2c_adap->algo_data; + unsigned long time_left; + + i2c_dev->msg = msg; + i2c_dev->buf = msg->buf; + i2c_dev->count = msg->len; + + reinit_completion(&i2c_dev->complete); + sprd_i2c_reset_fifo(i2c_dev); + sprd_i2c_set_devaddr(i2c_dev, msg); + sprd_i2c_set_count(i2c_dev, msg->len); + + if (msg->flags & I2C_M_RD) { + sprd_i2c_opt_mode(i2c_dev, 1); + sprd_i2c_send_stop(i2c_dev, 1); + } else { + sprd_i2c_opt_mode(i2c_dev, 0); + sprd_i2c_send_stop(i2c_dev, !!is_last_msg); + } + + /* + * We should enable rx fifo full interrupt to get data when receiving + * full data. + */ + if (msg->flags & I2C_M_RD) + sprd_i2c_set_fifo_full_int(i2c_dev, 1); + else + sprd_i2c_data_transfer(i2c_dev); + + sprd_i2c_opt_start(i2c_dev); + + time_left = wait_for_completion_timeout(&i2c_dev->complete, + msecs_to_jiffies(I2C_XFER_TIMEOUT)); + if (!time_left) + return -ETIMEDOUT; + + return i2c_dev->err; +} + +static int sprd_i2c_master_xfer(struct i2c_adapter *i2c_adap, + struct i2c_msg *msgs, int num) +{ + struct sprd_i2c *i2c_dev = i2c_adap->algo_data; + int im, ret; + + ret = pm_runtime_resume_and_get(i2c_dev->dev); + if (ret < 0) + return ret; + + for (im = 0; im < num - 1; im++) { + ret = sprd_i2c_handle_msg(i2c_adap, &msgs[im], 0); + if (ret) + goto err_msg; + } + + ret = sprd_i2c_handle_msg(i2c_adap, &msgs[im++], 1); + +err_msg: + pm_runtime_mark_last_busy(i2c_dev->dev); + pm_runtime_put_autosuspend(i2c_dev->dev); + + return ret < 0 ? ret : im; +} + +static u32 sprd_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm sprd_i2c_algo = { + .master_xfer = sprd_i2c_master_xfer, + .functionality = sprd_i2c_func, +}; + +static void sprd_i2c_set_clk(struct sprd_i2c *i2c_dev, u32 freq) +{ + u32 apb_clk = i2c_dev->src_clk; + /* + * From I2C databook, the prescale calculation formula: + * prescale = freq_i2c / (4 * freq_scl) - 1; + */ + u32 i2c_dvd = apb_clk / (4 * freq) - 1; + /* + * From I2C databook, the high period of SCL clock is recommended as + * 40% (2/5), and the low period of SCL clock is recommended as 60% + * (3/5), then the formula should be: + * high = (prescale * 2 * 2) / 5 + * low = (prescale * 2 * 3) / 5 + */ + u32 high = ((i2c_dvd << 1) * 2) / 5; + u32 low = ((i2c_dvd << 1) * 3) / 5; + u32 div0 = I2C_ADDR_DVD0_CALC(high, low); + u32 div1 = I2C_ADDR_DVD1_CALC(high, low); + + writel(div0, i2c_dev->base + ADDR_DVD0); + writel(div1, i2c_dev->base + ADDR_DVD1); + + /* Start hold timing = hold time(us) * source clock */ + if (freq == I2C_MAX_FAST_MODE_FREQ) + writel((6 * apb_clk) / 10000000, i2c_dev->base + ADDR_STA0_DVD); + else if (freq == I2C_MAX_STANDARD_MODE_FREQ) + writel((4 * apb_clk) / 1000000, i2c_dev->base + ADDR_STA0_DVD); +} + +static void sprd_i2c_enable(struct sprd_i2c *i2c_dev) +{ + u32 tmp = I2C_DVD_OPT; + + writel(tmp, i2c_dev->base + I2C_CTL); + + sprd_i2c_set_full_thld(i2c_dev, I2C_FIFO_FULL_THLD); + sprd_i2c_set_empty_thld(i2c_dev, I2C_FIFO_EMPTY_THLD); + + sprd_i2c_set_clk(i2c_dev, i2c_dev->bus_freq); + sprd_i2c_reset_fifo(i2c_dev); + sprd_i2c_clear_irq(i2c_dev); + + tmp = readl(i2c_dev->base + I2C_CTL); + writel(tmp | I2C_EN | I2C_INT_EN, i2c_dev->base + I2C_CTL); +} + +static irqreturn_t sprd_i2c_isr_thread(int irq, void *dev_id) +{ + struct sprd_i2c *i2c_dev = dev_id; + struct i2c_msg *msg = i2c_dev->msg; + bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK); + u32 i2c_tran; + + if (msg->flags & I2C_M_RD) + i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD; + else + i2c_tran = i2c_dev->count; + + /* + * If we got one ACK from slave when writing data, and we did not + * finish this transmission (i2c_tran is not zero), then we should + * continue to write data. + * + * For reading data, ack is always true, if i2c_tran is not 0 which + * means we still need to contine to read data from slave. + */ + if (i2c_tran && ack) { + sprd_i2c_data_transfer(i2c_dev); + return IRQ_HANDLED; + } + + i2c_dev->err = 0; + + /* + * If we did not get one ACK from slave when writing data, we should + * return -EIO to notify users. + */ + if (!ack) + i2c_dev->err = -EIO; + else if (msg->flags & I2C_M_RD && i2c_dev->count) + sprd_i2c_read_bytes(i2c_dev, i2c_dev->buf, i2c_dev->count); + + /* Transmission is done and clear ack and start operation */ + sprd_i2c_clear_ack(i2c_dev); + sprd_i2c_clear_start(i2c_dev); + complete(&i2c_dev->complete); + + return IRQ_HANDLED; +} + +static irqreturn_t sprd_i2c_isr(int irq, void *dev_id) +{ + struct sprd_i2c *i2c_dev = dev_id; + struct i2c_msg *msg = i2c_dev->msg; + bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK); + u32 i2c_tran; + + if (msg->flags & I2C_M_RD) + i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD; + else + i2c_tran = i2c_dev->count; + + /* + * If we did not get one ACK from slave when writing data, then we + * should finish this transmission since we got some errors. + * + * When writing data, if i2c_tran == 0 which means we have writen + * done all data, then we can finish this transmission. + * + * When reading data, if conut < rx fifo full threshold, which + * means we can read all data in one time, then we can finish this + * transmission too. + */ + if (!i2c_tran || !ack) { + sprd_i2c_clear_start(i2c_dev); + sprd_i2c_clear_irq(i2c_dev); + } + + sprd_i2c_set_fifo_empty_int(i2c_dev, 0); + sprd_i2c_set_fifo_full_int(i2c_dev, 0); + + return IRQ_WAKE_THREAD; +} + +static int sprd_i2c_clk_init(struct sprd_i2c *i2c_dev) +{ + struct clk *clk_i2c, *clk_parent; + + clk_i2c = devm_clk_get(i2c_dev->dev, "i2c"); + if (IS_ERR(clk_i2c)) { + dev_warn(i2c_dev->dev, "i2c%d can't get the i2c clock\n", + i2c_dev->adap.nr); + clk_i2c = NULL; + } + + clk_parent = devm_clk_get(i2c_dev->dev, "source"); + if (IS_ERR(clk_parent)) { + dev_warn(i2c_dev->dev, "i2c%d can't get the source clock\n", + i2c_dev->adap.nr); + clk_parent = NULL; + } + + if (clk_set_parent(clk_i2c, clk_parent)) + i2c_dev->src_clk = clk_get_rate(clk_i2c); + else + i2c_dev->src_clk = 26000000; + + dev_dbg(i2c_dev->dev, "i2c%d set source clock is %d\n", + i2c_dev->adap.nr, i2c_dev->src_clk); + + i2c_dev->clk = devm_clk_get(i2c_dev->dev, "enable"); + if (IS_ERR(i2c_dev->clk)) { + dev_err(i2c_dev->dev, "i2c%d can't get the enable clock\n", + i2c_dev->adap.nr); + return PTR_ERR(i2c_dev->clk); + } + + return 0; +} + +static int sprd_i2c_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct sprd_i2c *i2c_dev; + u32 prop; + int ret; + + pdev->id = of_alias_get_id(dev->of_node, "i2c"); + + i2c_dev = devm_kzalloc(dev, sizeof(struct sprd_i2c), GFP_KERNEL); + if (!i2c_dev) + return -ENOMEM; + + i2c_dev->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c_dev->base)) + return PTR_ERR(i2c_dev->base); + + i2c_dev->irq = platform_get_irq(pdev, 0); + if (i2c_dev->irq < 0) + return i2c_dev->irq; + + i2c_set_adapdata(&i2c_dev->adap, i2c_dev); + init_completion(&i2c_dev->complete); + snprintf(i2c_dev->adap.name, sizeof(i2c_dev->adap.name), + "%s", "sprd-i2c"); + + i2c_dev->bus_freq = I2C_MAX_STANDARD_MODE_FREQ; + i2c_dev->adap.owner = THIS_MODULE; + i2c_dev->dev = dev; + i2c_dev->adap.retries = 3; + i2c_dev->adap.algo = &sprd_i2c_algo; + i2c_dev->adap.algo_data = i2c_dev; + i2c_dev->adap.dev.parent = dev; + i2c_dev->adap.nr = pdev->id; + i2c_dev->adap.dev.of_node = dev->of_node; + + if (!of_property_read_u32(dev->of_node, "clock-frequency", &prop)) + i2c_dev->bus_freq = prop; + + /* We only support 100k and 400k now, otherwise will return error. */ + if (i2c_dev->bus_freq != I2C_MAX_STANDARD_MODE_FREQ && + i2c_dev->bus_freq != I2C_MAX_FAST_MODE_FREQ) + return -EINVAL; + + ret = sprd_i2c_clk_init(i2c_dev); + if (ret) + return ret; + + platform_set_drvdata(pdev, i2c_dev); + + ret = clk_prepare_enable(i2c_dev->clk); + if (ret) + return ret; + + sprd_i2c_enable(i2c_dev); + + pm_runtime_set_autosuspend_delay(i2c_dev->dev, SPRD_I2C_PM_TIMEOUT); + pm_runtime_use_autosuspend(i2c_dev->dev); + pm_runtime_set_active(i2c_dev->dev); + pm_runtime_enable(i2c_dev->dev); + + ret = pm_runtime_get_sync(i2c_dev->dev); + if (ret < 0) + goto err_rpm_put; + + ret = devm_request_threaded_irq(dev, i2c_dev->irq, + sprd_i2c_isr, sprd_i2c_isr_thread, + IRQF_NO_SUSPEND | IRQF_ONESHOT, + pdev->name, i2c_dev); + if (ret) { + dev_err(&pdev->dev, "failed to request irq %d\n", i2c_dev->irq); + goto err_rpm_put; + } + + ret = i2c_add_numbered_adapter(&i2c_dev->adap); + if (ret) { + dev_err(&pdev->dev, "add adapter failed\n"); + goto err_rpm_put; + } + + pm_runtime_mark_last_busy(i2c_dev->dev); + pm_runtime_put_autosuspend(i2c_dev->dev); + return 0; + +err_rpm_put: + pm_runtime_put_noidle(i2c_dev->dev); + pm_runtime_disable(i2c_dev->dev); + clk_disable_unprepare(i2c_dev->clk); + return ret; +} + +static int sprd_i2c_remove(struct platform_device *pdev) +{ + struct sprd_i2c *i2c_dev = platform_get_drvdata(pdev); + int ret; + + ret = pm_runtime_get_sync(i2c_dev->dev); + if (ret < 0) + dev_err(&pdev->dev, "Failed to resume device (%pe)\n", ERR_PTR(ret)); + + i2c_del_adapter(&i2c_dev->adap); + + if (ret >= 0) + clk_disable_unprepare(i2c_dev->clk); + + pm_runtime_put_noidle(i2c_dev->dev); + pm_runtime_disable(i2c_dev->dev); + + return 0; +} + +static int __maybe_unused sprd_i2c_suspend_noirq(struct device *dev) +{ + struct sprd_i2c *i2c_dev = dev_get_drvdata(dev); + + i2c_mark_adapter_suspended(&i2c_dev->adap); + return pm_runtime_force_suspend(dev); +} + +static int __maybe_unused sprd_i2c_resume_noirq(struct device *dev) +{ + struct sprd_i2c *i2c_dev = dev_get_drvdata(dev); + + i2c_mark_adapter_resumed(&i2c_dev->adap); + return pm_runtime_force_resume(dev); +} + +static int __maybe_unused sprd_i2c_runtime_suspend(struct device *dev) +{ + struct sprd_i2c *i2c_dev = dev_get_drvdata(dev); + + clk_disable_unprepare(i2c_dev->clk); + + return 0; +} + +static int __maybe_unused sprd_i2c_runtime_resume(struct device *dev) +{ + struct sprd_i2c *i2c_dev = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(i2c_dev->clk); + if (ret) + return ret; + + sprd_i2c_enable(i2c_dev); + + return 0; +} + +static const struct dev_pm_ops sprd_i2c_pm_ops = { + SET_RUNTIME_PM_OPS(sprd_i2c_runtime_suspend, + sprd_i2c_runtime_resume, NULL) + + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(sprd_i2c_suspend_noirq, + sprd_i2c_resume_noirq) +}; + +static const struct of_device_id sprd_i2c_of_match[] = { + { .compatible = "sprd,sc9860-i2c", }, + {}, +}; +MODULE_DEVICE_TABLE(of, sprd_i2c_of_match); + +static struct platform_driver sprd_i2c_driver = { + .probe = sprd_i2c_probe, + .remove = sprd_i2c_remove, + .driver = { + .name = "sprd-i2c", + .of_match_table = sprd_i2c_of_match, + .pm = &sprd_i2c_pm_ops, + }, +}; + +module_platform_driver(sprd_i2c_driver); + +MODULE_DESCRIPTION("Spreadtrum I2C master controller driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-st.c b/drivers/i2c/busses/i2c-st.c new file mode 100644 index 000000000..ce2333408 --- /dev/null +++ b/drivers/i2c/busses/i2c-st.c @@ -0,0 +1,906 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2013 STMicroelectronics + * + * I2C master mode controller driver, used in STMicroelectronics devices. + * + * Author: Maxime Coquelin <maxime.coquelin@st.com> + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> + +/* SSC registers */ +#define SSC_BRG 0x000 +#define SSC_TBUF 0x004 +#define SSC_RBUF 0x008 +#define SSC_CTL 0x00C +#define SSC_IEN 0x010 +#define SSC_STA 0x014 +#define SSC_I2C 0x018 +#define SSC_SLAD 0x01C +#define SSC_REP_START_HOLD 0x020 +#define SSC_START_HOLD 0x024 +#define SSC_REP_START_SETUP 0x028 +#define SSC_DATA_SETUP 0x02C +#define SSC_STOP_SETUP 0x030 +#define SSC_BUS_FREE 0x034 +#define SSC_TX_FSTAT 0x038 +#define SSC_RX_FSTAT 0x03C +#define SSC_PRE_SCALER_BRG 0x040 +#define SSC_CLR 0x080 +#define SSC_NOISE_SUPP_WIDTH 0x100 +#define SSC_PRSCALER 0x104 +#define SSC_NOISE_SUPP_WIDTH_DATAOUT 0x108 +#define SSC_PRSCALER_DATAOUT 0x10c + +/* SSC Control */ +#define SSC_CTL_DATA_WIDTH_9 0x8 +#define SSC_CTL_DATA_WIDTH_MSK 0xf +#define SSC_CTL_BM 0xf +#define SSC_CTL_HB BIT(4) +#define SSC_CTL_PH BIT(5) +#define SSC_CTL_PO BIT(6) +#define SSC_CTL_SR BIT(7) +#define SSC_CTL_MS BIT(8) +#define SSC_CTL_EN BIT(9) +#define SSC_CTL_LPB BIT(10) +#define SSC_CTL_EN_TX_FIFO BIT(11) +#define SSC_CTL_EN_RX_FIFO BIT(12) +#define SSC_CTL_EN_CLST_RX BIT(13) + +/* SSC Interrupt Enable */ +#define SSC_IEN_RIEN BIT(0) +#define SSC_IEN_TIEN BIT(1) +#define SSC_IEN_TEEN BIT(2) +#define SSC_IEN_REEN BIT(3) +#define SSC_IEN_PEEN BIT(4) +#define SSC_IEN_AASEN BIT(6) +#define SSC_IEN_STOPEN BIT(7) +#define SSC_IEN_ARBLEN BIT(8) +#define SSC_IEN_NACKEN BIT(10) +#define SSC_IEN_REPSTRTEN BIT(11) +#define SSC_IEN_TX_FIFO_HALF BIT(12) +#define SSC_IEN_RX_FIFO_HALF_FULL BIT(14) + +/* SSC Status */ +#define SSC_STA_RIR BIT(0) +#define SSC_STA_TIR BIT(1) +#define SSC_STA_TE BIT(2) +#define SSC_STA_RE BIT(3) +#define SSC_STA_PE BIT(4) +#define SSC_STA_CLST BIT(5) +#define SSC_STA_AAS BIT(6) +#define SSC_STA_STOP BIT(7) +#define SSC_STA_ARBL BIT(8) +#define SSC_STA_BUSY BIT(9) +#define SSC_STA_NACK BIT(10) +#define SSC_STA_REPSTRT BIT(11) +#define SSC_STA_TX_FIFO_HALF BIT(12) +#define SSC_STA_TX_FIFO_FULL BIT(13) +#define SSC_STA_RX_FIFO_HALF BIT(14) + +/* SSC I2C Control */ +#define SSC_I2C_I2CM BIT(0) +#define SSC_I2C_STRTG BIT(1) +#define SSC_I2C_STOPG BIT(2) +#define SSC_I2C_ACKG BIT(3) +#define SSC_I2C_AD10 BIT(4) +#define SSC_I2C_TXENB BIT(5) +#define SSC_I2C_REPSTRTG BIT(11) +#define SSC_I2C_SLAVE_DISABLE BIT(12) + +/* SSC Tx FIFO Status */ +#define SSC_TX_FSTAT_STATUS 0x07 + +/* SSC Rx FIFO Status */ +#define SSC_RX_FSTAT_STATUS 0x07 + +/* SSC Clear bit operation */ +#define SSC_CLR_SSCAAS BIT(6) +#define SSC_CLR_SSCSTOP BIT(7) +#define SSC_CLR_SSCARBL BIT(8) +#define SSC_CLR_NACK BIT(10) +#define SSC_CLR_REPSTRT BIT(11) + +/* SSC Clock Prescaler */ +#define SSC_PRSC_VALUE 0x0f + + +#define SSC_TXFIFO_SIZE 0x8 +#define SSC_RXFIFO_SIZE 0x8 + +enum st_i2c_mode { + I2C_MODE_STANDARD, + I2C_MODE_FAST, + I2C_MODE_END, +}; + +/** + * struct st_i2c_timings - per-Mode tuning parameters + * @rate: I2C bus rate + * @rep_start_hold: I2C repeated start hold time requirement + * @rep_start_setup: I2C repeated start set up time requirement + * @start_hold: I2C start hold time requirement + * @data_setup_time: I2C data set up time requirement + * @stop_setup_time: I2C stop set up time requirement + * @bus_free_time: I2C bus free time requirement + * @sda_pulse_min_limit: I2C SDA pulse mini width limit + */ +struct st_i2c_timings { + u32 rate; + u32 rep_start_hold; + u32 rep_start_setup; + u32 start_hold; + u32 data_setup_time; + u32 stop_setup_time; + u32 bus_free_time; + u32 sda_pulse_min_limit; +}; + +/** + * struct st_i2c_client - client specific data + * @addr: 8-bit slave addr, including r/w bit + * @count: number of bytes to be transfered + * @xfered: number of bytes already transferred + * @buf: data buffer + * @result: result of the transfer + * @stop: last I2C msg to be sent, i.e. STOP to be generated + */ +struct st_i2c_client { + u8 addr; + u32 count; + u32 xfered; + u8 *buf; + int result; + bool stop; +}; + +/** + * struct st_i2c_dev - private data of the controller + * @adap: I2C adapter for this controller + * @dev: device for this controller + * @base: virtual memory area + * @complete: completion of I2C message + * @irq: interrupt line for th controller + * @clk: hw ssc block clock + * @mode: I2C mode of the controller. Standard or Fast only supported + * @scl_min_width_us: SCL line minimum pulse width in us + * @sda_min_width_us: SDA line minimum pulse width in us + * @client: I2C transfert information + * @busy: I2C transfer on-going + */ +struct st_i2c_dev { + struct i2c_adapter adap; + struct device *dev; + void __iomem *base; + struct completion complete; + int irq; + struct clk *clk; + int mode; + u32 scl_min_width_us; + u32 sda_min_width_us; + struct st_i2c_client client; + bool busy; +}; + +static inline void st_i2c_set_bits(void __iomem *reg, u32 mask) +{ + writel_relaxed(readl_relaxed(reg) | mask, reg); +} + +static inline void st_i2c_clr_bits(void __iomem *reg, u32 mask) +{ + writel_relaxed(readl_relaxed(reg) & ~mask, reg); +} + +/* + * From I2C Specifications v0.5. + * + * All the values below have +10% margin added to be + * compatible with some out-of-spec devices, + * like HDMI link of the Toshiba 19AV600 TV. + */ +static struct st_i2c_timings i2c_timings[] = { + [I2C_MODE_STANDARD] = { + .rate = I2C_MAX_STANDARD_MODE_FREQ, + .rep_start_hold = 4400, + .rep_start_setup = 5170, + .start_hold = 4400, + .data_setup_time = 275, + .stop_setup_time = 4400, + .bus_free_time = 5170, + }, + [I2C_MODE_FAST] = { + .rate = I2C_MAX_FAST_MODE_FREQ, + .rep_start_hold = 660, + .rep_start_setup = 660, + .start_hold = 660, + .data_setup_time = 110, + .stop_setup_time = 660, + .bus_free_time = 1430, + }, +}; + +static void st_i2c_flush_rx_fifo(struct st_i2c_dev *i2c_dev) +{ + int count, i; + + /* + * Counter only counts up to 7 but fifo size is 8... + * When fifo is full, counter is 0 and RIR bit of status register is + * set + */ + if (readl_relaxed(i2c_dev->base + SSC_STA) & SSC_STA_RIR) + count = SSC_RXFIFO_SIZE; + else + count = readl_relaxed(i2c_dev->base + SSC_RX_FSTAT) & + SSC_RX_FSTAT_STATUS; + + for (i = 0; i < count; i++) + readl_relaxed(i2c_dev->base + SSC_RBUF); +} + +static void st_i2c_soft_reset(struct st_i2c_dev *i2c_dev) +{ + /* + * FIFO needs to be emptied before reseting the IP, + * else the controller raises a BUSY error. + */ + st_i2c_flush_rx_fifo(i2c_dev); + + st_i2c_set_bits(i2c_dev->base + SSC_CTL, SSC_CTL_SR); + st_i2c_clr_bits(i2c_dev->base + SSC_CTL, SSC_CTL_SR); +} + +/** + * st_i2c_hw_config() - Prepare SSC block, calculate and apply tuning timings + * @i2c_dev: Controller's private data + */ +static void st_i2c_hw_config(struct st_i2c_dev *i2c_dev) +{ + unsigned long rate; + u32 val, ns_per_clk; + struct st_i2c_timings *t = &i2c_timings[i2c_dev->mode]; + + st_i2c_soft_reset(i2c_dev); + + val = SSC_CLR_REPSTRT | SSC_CLR_NACK | SSC_CLR_SSCARBL | + SSC_CLR_SSCAAS | SSC_CLR_SSCSTOP; + writel_relaxed(val, i2c_dev->base + SSC_CLR); + + /* SSC Control register setup */ + val = SSC_CTL_PO | SSC_CTL_PH | SSC_CTL_HB | SSC_CTL_DATA_WIDTH_9; + writel_relaxed(val, i2c_dev->base + SSC_CTL); + + rate = clk_get_rate(i2c_dev->clk); + ns_per_clk = 1000000000 / rate; + + /* Baudrate */ + val = rate / (2 * t->rate); + writel_relaxed(val, i2c_dev->base + SSC_BRG); + + /* Pre-scaler baudrate */ + writel_relaxed(1, i2c_dev->base + SSC_PRE_SCALER_BRG); + + /* Enable I2C mode */ + writel_relaxed(SSC_I2C_I2CM, i2c_dev->base + SSC_I2C); + + /* Repeated start hold time */ + val = t->rep_start_hold / ns_per_clk; + writel_relaxed(val, i2c_dev->base + SSC_REP_START_HOLD); + + /* Repeated start set up time */ + val = t->rep_start_setup / ns_per_clk; + writel_relaxed(val, i2c_dev->base + SSC_REP_START_SETUP); + + /* Start hold time */ + val = t->start_hold / ns_per_clk; + writel_relaxed(val, i2c_dev->base + SSC_START_HOLD); + + /* Data set up time */ + val = t->data_setup_time / ns_per_clk; + writel_relaxed(val, i2c_dev->base + SSC_DATA_SETUP); + + /* Stop set up time */ + val = t->stop_setup_time / ns_per_clk; + writel_relaxed(val, i2c_dev->base + SSC_STOP_SETUP); + + /* Bus free time */ + val = t->bus_free_time / ns_per_clk; + writel_relaxed(val, i2c_dev->base + SSC_BUS_FREE); + + /* Prescalers set up */ + val = rate / 10000000; + writel_relaxed(val, i2c_dev->base + SSC_PRSCALER); + writel_relaxed(val, i2c_dev->base + SSC_PRSCALER_DATAOUT); + + /* Noise suppression witdh */ + val = i2c_dev->scl_min_width_us * rate / 100000000; + writel_relaxed(val, i2c_dev->base + SSC_NOISE_SUPP_WIDTH); + + /* Noise suppression max output data delay width */ + val = i2c_dev->sda_min_width_us * rate / 100000000; + writel_relaxed(val, i2c_dev->base + SSC_NOISE_SUPP_WIDTH_DATAOUT); +} + +static int st_i2c_recover_bus(struct i2c_adapter *i2c_adap) +{ + struct st_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap); + u32 ctl; + + dev_dbg(i2c_dev->dev, "Trying to recover bus\n"); + + /* + * SSP IP is dual role SPI/I2C to generate 9 clock pulses + * we switch to SPI node, 9 bit words and write a 0. This + * has been validate with a oscilloscope and is easier + * than switching to GPIO mode. + */ + + /* Disable interrupts */ + writel_relaxed(0, i2c_dev->base + SSC_IEN); + + st_i2c_hw_config(i2c_dev); + + ctl = SSC_CTL_EN | SSC_CTL_MS | SSC_CTL_EN_RX_FIFO | SSC_CTL_EN_TX_FIFO; + st_i2c_set_bits(i2c_dev->base + SSC_CTL, ctl); + + st_i2c_clr_bits(i2c_dev->base + SSC_I2C, SSC_I2C_I2CM); + usleep_range(8000, 10000); + + writel_relaxed(0, i2c_dev->base + SSC_TBUF); + usleep_range(2000, 4000); + st_i2c_set_bits(i2c_dev->base + SSC_I2C, SSC_I2C_I2CM); + + return 0; +} + +static int st_i2c_wait_free_bus(struct st_i2c_dev *i2c_dev) +{ + u32 sta; + int i, ret; + + for (i = 0; i < 10; i++) { + sta = readl_relaxed(i2c_dev->base + SSC_STA); + if (!(sta & SSC_STA_BUSY)) + return 0; + + usleep_range(2000, 4000); + } + + dev_err(i2c_dev->dev, "bus not free (status = 0x%08x)\n", sta); + + ret = i2c_recover_bus(&i2c_dev->adap); + if (ret) { + dev_err(i2c_dev->dev, "Failed to recover the bus (%d)\n", ret); + return ret; + } + + return -EBUSY; +} + +/** + * st_i2c_write_tx_fifo() - Write a byte in the Tx FIFO + * @i2c_dev: Controller's private data + * @byte: Data to write in the Tx FIFO + */ +static inline void st_i2c_write_tx_fifo(struct st_i2c_dev *i2c_dev, u8 byte) +{ + u16 tbuf = byte << 1; + + writel_relaxed(tbuf | 1, i2c_dev->base + SSC_TBUF); +} + +/** + * st_i2c_wr_fill_tx_fifo() - Fill the Tx FIFO in write mode + * @i2c_dev: Controller's private data + * + * This functions fills the Tx FIFO with I2C transfert buffer when + * in write mode. + */ +static void st_i2c_wr_fill_tx_fifo(struct st_i2c_dev *i2c_dev) +{ + struct st_i2c_client *c = &i2c_dev->client; + u32 tx_fstat, sta; + int i; + + sta = readl_relaxed(i2c_dev->base + SSC_STA); + if (sta & SSC_STA_TX_FIFO_FULL) + return; + + tx_fstat = readl_relaxed(i2c_dev->base + SSC_TX_FSTAT); + tx_fstat &= SSC_TX_FSTAT_STATUS; + + if (c->count < (SSC_TXFIFO_SIZE - tx_fstat)) + i = c->count; + else + i = SSC_TXFIFO_SIZE - tx_fstat; + + for (; i > 0; i--, c->count--, c->buf++) + st_i2c_write_tx_fifo(i2c_dev, *c->buf); +} + +/** + * st_i2c_rd_fill_tx_fifo() - Fill the Tx FIFO in read mode + * @i2c_dev: Controller's private data + * @max: Maximum amount of data to fill into the Tx FIFO + * + * This functions fills the Tx FIFO with fixed pattern when + * in read mode to trigger clock. + */ +static void st_i2c_rd_fill_tx_fifo(struct st_i2c_dev *i2c_dev, int max) +{ + struct st_i2c_client *c = &i2c_dev->client; + u32 tx_fstat, sta; + int i; + + sta = readl_relaxed(i2c_dev->base + SSC_STA); + if (sta & SSC_STA_TX_FIFO_FULL) + return; + + tx_fstat = readl_relaxed(i2c_dev->base + SSC_TX_FSTAT); + tx_fstat &= SSC_TX_FSTAT_STATUS; + + if (max < (SSC_TXFIFO_SIZE - tx_fstat)) + i = max; + else + i = SSC_TXFIFO_SIZE - tx_fstat; + + for (; i > 0; i--, c->xfered++) + st_i2c_write_tx_fifo(i2c_dev, 0xff); +} + +static void st_i2c_read_rx_fifo(struct st_i2c_dev *i2c_dev) +{ + struct st_i2c_client *c = &i2c_dev->client; + u32 i, sta; + u16 rbuf; + + sta = readl_relaxed(i2c_dev->base + SSC_STA); + if (sta & SSC_STA_RIR) { + i = SSC_RXFIFO_SIZE; + } else { + i = readl_relaxed(i2c_dev->base + SSC_RX_FSTAT); + i &= SSC_RX_FSTAT_STATUS; + } + + for (; (i > 0) && (c->count > 0); i--, c->count--) { + rbuf = readl_relaxed(i2c_dev->base + SSC_RBUF) >> 1; + *c->buf++ = (u8)rbuf & 0xff; + } + + if (i) { + dev_err(i2c_dev->dev, "Unexpected %d bytes in rx fifo\n", i); + st_i2c_flush_rx_fifo(i2c_dev); + } +} + +/** + * st_i2c_terminate_xfer() - Send either STOP or REPSTART condition + * @i2c_dev: Controller's private data + */ +static void st_i2c_terminate_xfer(struct st_i2c_dev *i2c_dev) +{ + struct st_i2c_client *c = &i2c_dev->client; + + st_i2c_clr_bits(i2c_dev->base + SSC_IEN, SSC_IEN_TEEN); + st_i2c_clr_bits(i2c_dev->base + SSC_I2C, SSC_I2C_STRTG); + + if (c->stop) { + st_i2c_set_bits(i2c_dev->base + SSC_IEN, SSC_IEN_STOPEN); + st_i2c_set_bits(i2c_dev->base + SSC_I2C, SSC_I2C_STOPG); + } else { + st_i2c_set_bits(i2c_dev->base + SSC_IEN, SSC_IEN_REPSTRTEN); + st_i2c_set_bits(i2c_dev->base + SSC_I2C, SSC_I2C_REPSTRTG); + } +} + +/** + * st_i2c_handle_write() - Handle FIFO empty interrupt in case of write + * @i2c_dev: Controller's private data + */ +static void st_i2c_handle_write(struct st_i2c_dev *i2c_dev) +{ + struct st_i2c_client *c = &i2c_dev->client; + + st_i2c_flush_rx_fifo(i2c_dev); + + if (!c->count) + /* End of xfer, send stop or repstart */ + st_i2c_terminate_xfer(i2c_dev); + else + st_i2c_wr_fill_tx_fifo(i2c_dev); +} + +/** + * st_i2c_handle_read() - Handle FIFO empty interrupt in case of read + * @i2c_dev: Controller's private data + */ +static void st_i2c_handle_read(struct st_i2c_dev *i2c_dev) +{ + struct st_i2c_client *c = &i2c_dev->client; + u32 ien; + + /* Trash the address read back */ + if (!c->xfered) { + readl_relaxed(i2c_dev->base + SSC_RBUF); + st_i2c_clr_bits(i2c_dev->base + SSC_I2C, SSC_I2C_TXENB); + } else { + st_i2c_read_rx_fifo(i2c_dev); + } + + if (!c->count) { + /* End of xfer, send stop or repstart */ + st_i2c_terminate_xfer(i2c_dev); + } else if (c->count == 1) { + /* Penultimate byte to xfer, disable ACK gen. */ + st_i2c_clr_bits(i2c_dev->base + SSC_I2C, SSC_I2C_ACKG); + + /* Last received byte is to be handled by NACK interrupt */ + ien = SSC_IEN_NACKEN | SSC_IEN_ARBLEN; + writel_relaxed(ien, i2c_dev->base + SSC_IEN); + + st_i2c_rd_fill_tx_fifo(i2c_dev, c->count); + } else { + st_i2c_rd_fill_tx_fifo(i2c_dev, c->count - 1); + } +} + +/** + * st_i2c_isr_thread() - Interrupt routine + * @irq: interrupt number + * @data: Controller's private data + */ +static irqreturn_t st_i2c_isr_thread(int irq, void *data) +{ + struct st_i2c_dev *i2c_dev = data; + struct st_i2c_client *c = &i2c_dev->client; + u32 sta, ien; + int it; + + ien = readl_relaxed(i2c_dev->base + SSC_IEN); + sta = readl_relaxed(i2c_dev->base + SSC_STA); + + /* Use __fls() to check error bits first */ + it = __fls(sta & ien); + if (it < 0) { + dev_dbg(i2c_dev->dev, "spurious it (sta=0x%04x, ien=0x%04x)\n", + sta, ien); + return IRQ_NONE; + } + + switch (1 << it) { + case SSC_STA_TE: + if (c->addr & I2C_M_RD) + st_i2c_handle_read(i2c_dev); + else + st_i2c_handle_write(i2c_dev); + break; + + case SSC_STA_STOP: + case SSC_STA_REPSTRT: + writel_relaxed(0, i2c_dev->base + SSC_IEN); + complete(&i2c_dev->complete); + break; + + case SSC_STA_NACK: + writel_relaxed(SSC_CLR_NACK, i2c_dev->base + SSC_CLR); + + /* Last received byte handled by NACK interrupt */ + if ((c->addr & I2C_M_RD) && (c->count == 1) && (c->xfered)) { + st_i2c_handle_read(i2c_dev); + break; + } + + it = SSC_IEN_STOPEN | SSC_IEN_ARBLEN; + writel_relaxed(it, i2c_dev->base + SSC_IEN); + + st_i2c_set_bits(i2c_dev->base + SSC_I2C, SSC_I2C_STOPG); + c->result = -EIO; + break; + + case SSC_STA_ARBL: + writel_relaxed(SSC_CLR_SSCARBL, i2c_dev->base + SSC_CLR); + + it = SSC_IEN_STOPEN | SSC_IEN_ARBLEN; + writel_relaxed(it, i2c_dev->base + SSC_IEN); + + st_i2c_set_bits(i2c_dev->base + SSC_I2C, SSC_I2C_STOPG); + c->result = -EAGAIN; + break; + + default: + dev_err(i2c_dev->dev, + "it %d unhandled (sta=0x%04x)\n", it, sta); + } + + /* + * Read IEN register to ensure interrupt mask write is effective + * before re-enabling interrupt at GIC level, and thus avoid spurious + * interrupts. + */ + readl(i2c_dev->base + SSC_IEN); + + return IRQ_HANDLED; +} + +/** + * st_i2c_xfer_msg() - Transfer a single I2C message + * @i2c_dev: Controller's private data + * @msg: I2C message to transfer + * @is_first: first message of the sequence + * @is_last: last message of the sequence + */ +static int st_i2c_xfer_msg(struct st_i2c_dev *i2c_dev, struct i2c_msg *msg, + bool is_first, bool is_last) +{ + struct st_i2c_client *c = &i2c_dev->client; + u32 ctl, i2c, it; + unsigned long timeout; + int ret; + + c->addr = i2c_8bit_addr_from_msg(msg); + c->buf = msg->buf; + c->count = msg->len; + c->xfered = 0; + c->result = 0; + c->stop = is_last; + + reinit_completion(&i2c_dev->complete); + + ctl = SSC_CTL_EN | SSC_CTL_MS | SSC_CTL_EN_RX_FIFO | SSC_CTL_EN_TX_FIFO; + st_i2c_set_bits(i2c_dev->base + SSC_CTL, ctl); + + i2c = SSC_I2C_TXENB; + if (c->addr & I2C_M_RD) + i2c |= SSC_I2C_ACKG; + st_i2c_set_bits(i2c_dev->base + SSC_I2C, i2c); + + /* Write slave address */ + st_i2c_write_tx_fifo(i2c_dev, c->addr); + + /* Pre-fill Tx fifo with data in case of write */ + if (!(c->addr & I2C_M_RD)) + st_i2c_wr_fill_tx_fifo(i2c_dev); + + it = SSC_IEN_NACKEN | SSC_IEN_TEEN | SSC_IEN_ARBLEN; + writel_relaxed(it, i2c_dev->base + SSC_IEN); + + if (is_first) { + ret = st_i2c_wait_free_bus(i2c_dev); + if (ret) + return ret; + + st_i2c_set_bits(i2c_dev->base + SSC_I2C, SSC_I2C_STRTG); + } + + timeout = wait_for_completion_timeout(&i2c_dev->complete, + i2c_dev->adap.timeout); + ret = c->result; + + if (!timeout) { + dev_err(i2c_dev->dev, "Write to slave 0x%x timed out\n", + c->addr); + ret = -ETIMEDOUT; + } + + i2c = SSC_I2C_STOPG | SSC_I2C_REPSTRTG; + st_i2c_clr_bits(i2c_dev->base + SSC_I2C, i2c); + + writel_relaxed(SSC_CLR_SSCSTOP | SSC_CLR_REPSTRT, + i2c_dev->base + SSC_CLR); + + return ret; +} + +/** + * st_i2c_xfer() - Transfer a single I2C message + * @i2c_adap: Adapter pointer to the controller + * @msgs: Pointer to data to be written. + * @num: Number of messages to be executed + */ +static int st_i2c_xfer(struct i2c_adapter *i2c_adap, + struct i2c_msg msgs[], int num) +{ + struct st_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap); + int ret, i; + + i2c_dev->busy = true; + + ret = clk_prepare_enable(i2c_dev->clk); + if (ret) { + dev_err(i2c_dev->dev, "Failed to prepare_enable clock\n"); + return ret; + } + + pinctrl_pm_select_default_state(i2c_dev->dev); + + st_i2c_hw_config(i2c_dev); + + for (i = 0; (i < num) && !ret; i++) + ret = st_i2c_xfer_msg(i2c_dev, &msgs[i], i == 0, i == num - 1); + + pinctrl_pm_select_idle_state(i2c_dev->dev); + + clk_disable_unprepare(i2c_dev->clk); + + i2c_dev->busy = false; + + return (ret < 0) ? ret : i; +} + +static int st_i2c_suspend(struct device *dev) +{ + struct st_i2c_dev *i2c_dev = dev_get_drvdata(dev); + + if (i2c_dev->busy) + return -EBUSY; + + pinctrl_pm_select_sleep_state(dev); + + return 0; +} + +static int st_i2c_resume(struct device *dev) +{ + pinctrl_pm_select_default_state(dev); + /* Go in idle state if available */ + pinctrl_pm_select_idle_state(dev); + + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(st_i2c_pm, st_i2c_suspend, st_i2c_resume); + +static u32 st_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm st_i2c_algo = { + .master_xfer = st_i2c_xfer, + .functionality = st_i2c_func, +}; + +static struct i2c_bus_recovery_info st_i2c_recovery_info = { + .recover_bus = st_i2c_recover_bus, +}; + +static int st_i2c_of_get_deglitch(struct device_node *np, + struct st_i2c_dev *i2c_dev) +{ + int ret; + + ret = of_property_read_u32(np, "st,i2c-min-scl-pulse-width-us", + &i2c_dev->scl_min_width_us); + if ((ret == -ENODATA) || (ret == -EOVERFLOW)) { + dev_err(i2c_dev->dev, "st,i2c-min-scl-pulse-width-us invalid\n"); + return ret; + } + + ret = of_property_read_u32(np, "st,i2c-min-sda-pulse-width-us", + &i2c_dev->sda_min_width_us); + if ((ret == -ENODATA) || (ret == -EOVERFLOW)) { + dev_err(i2c_dev->dev, "st,i2c-min-sda-pulse-width-us invalid\n"); + return ret; + } + + return 0; +} + +static int st_i2c_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct st_i2c_dev *i2c_dev; + struct resource *res; + u32 clk_rate; + struct i2c_adapter *adap; + int ret; + + i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); + if (!i2c_dev) + return -ENOMEM; + + i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(i2c_dev->base)) + return PTR_ERR(i2c_dev->base); + + i2c_dev->irq = irq_of_parse_and_map(np, 0); + if (!i2c_dev->irq) { + dev_err(&pdev->dev, "IRQ missing or invalid\n"); + return -EINVAL; + } + + i2c_dev->clk = of_clk_get_by_name(np, "ssc"); + if (IS_ERR(i2c_dev->clk)) { + dev_err(&pdev->dev, "Unable to request clock\n"); + return PTR_ERR(i2c_dev->clk); + } + + i2c_dev->mode = I2C_MODE_STANDARD; + ret = of_property_read_u32(np, "clock-frequency", &clk_rate); + if (!ret && (clk_rate == I2C_MAX_FAST_MODE_FREQ)) + i2c_dev->mode = I2C_MODE_FAST; + + i2c_dev->dev = &pdev->dev; + + ret = devm_request_threaded_irq(&pdev->dev, i2c_dev->irq, + NULL, st_i2c_isr_thread, + IRQF_ONESHOT, pdev->name, i2c_dev); + if (ret) { + dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq); + return ret; + } + + pinctrl_pm_select_default_state(i2c_dev->dev); + /* In case idle state available, select it */ + pinctrl_pm_select_idle_state(i2c_dev->dev); + + ret = st_i2c_of_get_deglitch(np, i2c_dev); + if (ret) + return ret; + + adap = &i2c_dev->adap; + i2c_set_adapdata(adap, i2c_dev); + snprintf(adap->name, sizeof(adap->name), "ST I2C(%pa)", &res->start); + adap->owner = THIS_MODULE; + adap->timeout = 2 * HZ; + adap->retries = 0; + adap->algo = &st_i2c_algo; + adap->bus_recovery_info = &st_i2c_recovery_info; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + + init_completion(&i2c_dev->complete); + + ret = i2c_add_adapter(adap); + if (ret) + return ret; + + platform_set_drvdata(pdev, i2c_dev); + + dev_info(i2c_dev->dev, "%s initialized\n", adap->name); + + return 0; +} + +static void st_i2c_remove(struct platform_device *pdev) +{ + struct st_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c_dev->adap); +} + +static const struct of_device_id st_i2c_match[] = { + { .compatible = "st,comms-ssc-i2c", }, + { .compatible = "st,comms-ssc4-i2c", }, + {}, +}; +MODULE_DEVICE_TABLE(of, st_i2c_match); + +static struct platform_driver st_i2c_driver = { + .driver = { + .name = "st-i2c", + .of_match_table = st_i2c_match, + .pm = pm_sleep_ptr(&st_i2c_pm), + }, + .probe = st_i2c_probe, + .remove_new = st_i2c_remove, +}; + +module_platform_driver(st_i2c_driver); + +MODULE_AUTHOR("Maxime Coquelin <maxime.coquelin@st.com>"); +MODULE_DESCRIPTION("STMicroelectronics I2C driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-stm32.c b/drivers/i2c/busses/i2c-stm32.c new file mode 100644 index 000000000..157c64e27 --- /dev/null +++ b/drivers/i2c/busses/i2c-stm32.c @@ -0,0 +1,156 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * i2c-stm32.c + * + * Copyright (C) M'boumba Cedric Madianga 2017 + * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com> + */ + +#include "i2c-stm32.h" + +/* Functions for DMA support */ +struct stm32_i2c_dma *stm32_i2c_dma_request(struct device *dev, + dma_addr_t phy_addr, + u32 txdr_offset, + u32 rxdr_offset) +{ + struct stm32_i2c_dma *dma; + struct dma_slave_config dma_sconfig; + int ret; + + dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL); + if (!dma) + return ERR_PTR(-ENOMEM); + + /* Request and configure I2C TX dma channel */ + dma->chan_tx = dma_request_chan(dev, "tx"); + if (IS_ERR(dma->chan_tx)) { + ret = PTR_ERR(dma->chan_tx); + if (ret != -ENODEV) + ret = dev_err_probe(dev, ret, + "can't request DMA tx channel\n"); + goto fail_al; + } + + memset(&dma_sconfig, 0, sizeof(dma_sconfig)); + dma_sconfig.dst_addr = phy_addr + txdr_offset; + dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + dma_sconfig.dst_maxburst = 1; + dma_sconfig.direction = DMA_MEM_TO_DEV; + ret = dmaengine_slave_config(dma->chan_tx, &dma_sconfig); + if (ret < 0) { + dev_err(dev, "can't configure tx channel\n"); + goto fail_tx; + } + + /* Request and configure I2C RX dma channel */ + dma->chan_rx = dma_request_chan(dev, "rx"); + if (IS_ERR(dma->chan_rx)) { + ret = PTR_ERR(dma->chan_rx); + if (ret != -ENODEV) + ret = dev_err_probe(dev, ret, + "can't request DMA rx channel\n"); + + goto fail_tx; + } + + memset(&dma_sconfig, 0, sizeof(dma_sconfig)); + dma_sconfig.src_addr = phy_addr + rxdr_offset; + dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + dma_sconfig.src_maxburst = 1; + dma_sconfig.direction = DMA_DEV_TO_MEM; + ret = dmaengine_slave_config(dma->chan_rx, &dma_sconfig); + if (ret < 0) { + dev_err(dev, "can't configure rx channel\n"); + goto fail_rx; + } + + init_completion(&dma->dma_complete); + + dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n", + dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx)); + + return dma; + +fail_rx: + dma_release_channel(dma->chan_rx); +fail_tx: + dma_release_channel(dma->chan_tx); +fail_al: + devm_kfree(dev, dma); + + return ERR_PTR(ret); +} + +void stm32_i2c_dma_free(struct stm32_i2c_dma *dma) +{ + dma->dma_buf = 0; + dma->dma_len = 0; + + dma_release_channel(dma->chan_tx); + dma->chan_tx = NULL; + + dma_release_channel(dma->chan_rx); + dma->chan_rx = NULL; + + dma->chan_using = NULL; +} + +int stm32_i2c_prep_dma_xfer(struct device *dev, struct stm32_i2c_dma *dma, + bool rd_wr, u32 len, u8 *buf, + dma_async_tx_callback callback, + void *dma_async_param) +{ + struct dma_async_tx_descriptor *txdesc; + struct device *chan_dev; + int ret; + + if (rd_wr) { + dma->chan_using = dma->chan_rx; + dma->dma_transfer_dir = DMA_DEV_TO_MEM; + dma->dma_data_dir = DMA_FROM_DEVICE; + } else { + dma->chan_using = dma->chan_tx; + dma->dma_transfer_dir = DMA_MEM_TO_DEV; + dma->dma_data_dir = DMA_TO_DEVICE; + } + + dma->dma_len = len; + chan_dev = dma->chan_using->device->dev; + + dma->dma_buf = dma_map_single(chan_dev, buf, dma->dma_len, + dma->dma_data_dir); + if (dma_mapping_error(chan_dev, dma->dma_buf)) { + dev_err(dev, "DMA mapping failed\n"); + return -EINVAL; + } + + txdesc = dmaengine_prep_slave_single(dma->chan_using, dma->dma_buf, + dma->dma_len, + dma->dma_transfer_dir, + DMA_PREP_INTERRUPT); + if (!txdesc) { + dev_err(dev, "Not able to get desc for DMA xfer\n"); + ret = -EINVAL; + goto err; + } + + reinit_completion(&dma->dma_complete); + + txdesc->callback = callback; + txdesc->callback_param = dma_async_param; + ret = dma_submit_error(dmaengine_submit(txdesc)); + if (ret < 0) { + dev_err(dev, "DMA submit failed\n"); + goto err; + } + + dma_async_issue_pending(dma->chan_using); + + return 0; + +err: + dma_unmap_single(chan_dev, dma->dma_buf, dma->dma_len, + dma->dma_data_dir); + return ret; +} diff --git a/drivers/i2c/busses/i2c-stm32.h b/drivers/i2c/busses/i2c-stm32.h new file mode 100644 index 000000000..2c2189390 --- /dev/null +++ b/drivers/i2c/busses/i2c-stm32.h @@ -0,0 +1,58 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * i2c-stm32.h + * + * Copyright (C) M'boumba Cedric Madianga 2017 + * Copyright (C) STMicroelectronics 2017 + * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com> + * + */ + +#ifndef _I2C_STM32_H +#define _I2C_STM32_H + +#include <linux/dma-direction.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> + +enum stm32_i2c_speed { + STM32_I2C_SPEED_STANDARD, /* 100 kHz */ + STM32_I2C_SPEED_FAST, /* 400 kHz */ + STM32_I2C_SPEED_FAST_PLUS, /* 1 MHz */ + STM32_I2C_SPEED_END, +}; + +/** + * struct stm32_i2c_dma - DMA specific data + * @chan_tx: dma channel for TX transfer + * @chan_rx: dma channel for RX transfer + * @chan_using: dma channel used for the current transfer (TX or RX) + * @dma_buf: dma buffer + * @dma_len: dma buffer len + * @dma_transfer_dir: dma transfer direction indicator + * @dma_data_dir: dma transfer mode indicator + * @dma_complete: dma transfer completion + */ +struct stm32_i2c_dma { + struct dma_chan *chan_tx; + struct dma_chan *chan_rx; + struct dma_chan *chan_using; + dma_addr_t dma_buf; + unsigned int dma_len; + enum dma_transfer_direction dma_transfer_dir; + enum dma_data_direction dma_data_dir; + struct completion dma_complete; +}; + +struct stm32_i2c_dma *stm32_i2c_dma_request(struct device *dev, + dma_addr_t phy_addr, + u32 txdr_offset, u32 rxdr_offset); + +void stm32_i2c_dma_free(struct stm32_i2c_dma *dma); + +int stm32_i2c_prep_dma_xfer(struct device *dev, struct stm32_i2c_dma *dma, + bool rd_wr, u32 len, u8 *buf, + dma_async_tx_callback callback, + void *dma_async_param); + +#endif /* _I2C_STM32_H */ diff --git a/drivers/i2c/busses/i2c-stm32f4.c b/drivers/i2c/busses/i2c-stm32f4.c new file mode 100644 index 000000000..ecc54792a --- /dev/null +++ b/drivers/i2c/busses/i2c-stm32f4.c @@ -0,0 +1,891 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for STMicroelectronics STM32 I2C controller + * + * This I2C controller is described in the STM32F429/439 Soc reference manual. + * Please see below a link to the documentation: + * http://www.st.com/resource/en/reference_manual/DM00031020.pdf + * + * Copyright (C) M'boumba Cedric Madianga 2016 + * Copyright (C) STMicroelectronics 2017 + * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com> + * + * This driver is based on i2c-st.c + * + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reset.h> + +#include "i2c-stm32.h" + +/* STM32F4 I2C offset registers */ +#define STM32F4_I2C_CR1 0x00 +#define STM32F4_I2C_CR2 0x04 +#define STM32F4_I2C_DR 0x10 +#define STM32F4_I2C_SR1 0x14 +#define STM32F4_I2C_SR2 0x18 +#define STM32F4_I2C_CCR 0x1C +#define STM32F4_I2C_TRISE 0x20 +#define STM32F4_I2C_FLTR 0x24 + +/* STM32F4 I2C control 1*/ +#define STM32F4_I2C_CR1_POS BIT(11) +#define STM32F4_I2C_CR1_ACK BIT(10) +#define STM32F4_I2C_CR1_STOP BIT(9) +#define STM32F4_I2C_CR1_START BIT(8) +#define STM32F4_I2C_CR1_PE BIT(0) + +/* STM32F4 I2C control 2 */ +#define STM32F4_I2C_CR2_FREQ_MASK GENMASK(5, 0) +#define STM32F4_I2C_CR2_FREQ(n) ((n) & STM32F4_I2C_CR2_FREQ_MASK) +#define STM32F4_I2C_CR2_ITBUFEN BIT(10) +#define STM32F4_I2C_CR2_ITEVTEN BIT(9) +#define STM32F4_I2C_CR2_ITERREN BIT(8) +#define STM32F4_I2C_CR2_IRQ_MASK (STM32F4_I2C_CR2_ITBUFEN | \ + STM32F4_I2C_CR2_ITEVTEN | \ + STM32F4_I2C_CR2_ITERREN) + +/* STM32F4 I2C Status 1 */ +#define STM32F4_I2C_SR1_AF BIT(10) +#define STM32F4_I2C_SR1_ARLO BIT(9) +#define STM32F4_I2C_SR1_BERR BIT(8) +#define STM32F4_I2C_SR1_TXE BIT(7) +#define STM32F4_I2C_SR1_RXNE BIT(6) +#define STM32F4_I2C_SR1_BTF BIT(2) +#define STM32F4_I2C_SR1_ADDR BIT(1) +#define STM32F4_I2C_SR1_SB BIT(0) +#define STM32F4_I2C_SR1_ITEVTEN_MASK (STM32F4_I2C_SR1_BTF | \ + STM32F4_I2C_SR1_ADDR | \ + STM32F4_I2C_SR1_SB) +#define STM32F4_I2C_SR1_ITBUFEN_MASK (STM32F4_I2C_SR1_TXE | \ + STM32F4_I2C_SR1_RXNE) +#define STM32F4_I2C_SR1_ITERREN_MASK (STM32F4_I2C_SR1_AF | \ + STM32F4_I2C_SR1_ARLO | \ + STM32F4_I2C_SR1_BERR) + +/* STM32F4 I2C Status 2 */ +#define STM32F4_I2C_SR2_BUSY BIT(1) + +/* STM32F4 I2C Control Clock */ +#define STM32F4_I2C_CCR_CCR_MASK GENMASK(11, 0) +#define STM32F4_I2C_CCR_CCR(n) ((n) & STM32F4_I2C_CCR_CCR_MASK) +#define STM32F4_I2C_CCR_FS BIT(15) +#define STM32F4_I2C_CCR_DUTY BIT(14) + +/* STM32F4 I2C Trise */ +#define STM32F4_I2C_TRISE_VALUE_MASK GENMASK(5, 0) +#define STM32F4_I2C_TRISE_VALUE(n) ((n) & STM32F4_I2C_TRISE_VALUE_MASK) + +#define STM32F4_I2C_MIN_STANDARD_FREQ 2U +#define STM32F4_I2C_MIN_FAST_FREQ 6U +#define STM32F4_I2C_MAX_FREQ 46U +#define HZ_TO_MHZ 1000000 + +/** + * struct stm32f4_i2c_msg - client specific data + * @addr: 8-bit slave addr, including r/w bit + * @count: number of bytes to be transferred + * @buf: data buffer + * @result: result of the transfer + * @stop: last I2C msg to be sent, i.e. STOP to be generated + */ +struct stm32f4_i2c_msg { + u8 addr; + u32 count; + u8 *buf; + int result; + bool stop; +}; + +/** + * struct stm32f4_i2c_dev - private data of the controller + * @adap: I2C adapter for this controller + * @dev: device for this controller + * @base: virtual memory area + * @complete: completion of I2C message + * @clk: hw i2c clock + * @speed: I2C clock frequency of the controller. Standard or Fast are supported + * @parent_rate: I2C clock parent rate in MHz + * @msg: I2C transfer information + */ +struct stm32f4_i2c_dev { + struct i2c_adapter adap; + struct device *dev; + void __iomem *base; + struct completion complete; + struct clk *clk; + int speed; + int parent_rate; + struct stm32f4_i2c_msg msg; +}; + +static inline void stm32f4_i2c_set_bits(void __iomem *reg, u32 mask) +{ + writel_relaxed(readl_relaxed(reg) | mask, reg); +} + +static inline void stm32f4_i2c_clr_bits(void __iomem *reg, u32 mask) +{ + writel_relaxed(readl_relaxed(reg) & ~mask, reg); +} + +static void stm32f4_i2c_disable_irq(struct stm32f4_i2c_dev *i2c_dev) +{ + void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR2; + + stm32f4_i2c_clr_bits(reg, STM32F4_I2C_CR2_IRQ_MASK); +} + +static int stm32f4_i2c_set_periph_clk_freq(struct stm32f4_i2c_dev *i2c_dev) +{ + u32 freq; + u32 cr2 = 0; + + i2c_dev->parent_rate = clk_get_rate(i2c_dev->clk); + freq = DIV_ROUND_UP(i2c_dev->parent_rate, HZ_TO_MHZ); + + if (i2c_dev->speed == STM32_I2C_SPEED_STANDARD) { + /* + * To reach 100 kHz, the parent clk frequency should be between + * a minimum value of 2 MHz and a maximum value of 46 MHz due + * to hardware limitation + */ + if (freq < STM32F4_I2C_MIN_STANDARD_FREQ || + freq > STM32F4_I2C_MAX_FREQ) { + dev_err(i2c_dev->dev, + "bad parent clk freq for standard mode\n"); + return -EINVAL; + } + } else { + /* + * To be as close as possible to 400 kHz, the parent clk + * frequency should be between a minimum value of 6 MHz and a + * maximum value of 46 MHz due to hardware limitation + */ + if (freq < STM32F4_I2C_MIN_FAST_FREQ || + freq > STM32F4_I2C_MAX_FREQ) { + dev_err(i2c_dev->dev, + "bad parent clk freq for fast mode\n"); + return -EINVAL; + } + } + + cr2 |= STM32F4_I2C_CR2_FREQ(freq); + writel_relaxed(cr2, i2c_dev->base + STM32F4_I2C_CR2); + + return 0; +} + +static void stm32f4_i2c_set_rise_time(struct stm32f4_i2c_dev *i2c_dev) +{ + u32 freq = DIV_ROUND_UP(i2c_dev->parent_rate, HZ_TO_MHZ); + u32 trise; + + /* + * These bits must be programmed with the maximum SCL rise time given in + * the I2C bus specification, incremented by 1. + * + * In standard mode, the maximum allowed SCL rise time is 1000 ns. + * If, in the I2C_CR2 register, the value of FREQ[5:0] bits is equal to + * 0x08 so period = 125 ns therefore the TRISE[5:0] bits must be + * programmed with 0x9. (1000 ns / 125 ns + 1) + * So, for I2C standard mode TRISE = FREQ[5:0] + 1 + * + * In fast mode, the maximum allowed SCL rise time is 300 ns. + * If, in the I2C_CR2 register, the value of FREQ[5:0] bits is equal to + * 0x08 so period = 125 ns therefore the TRISE[5:0] bits must be + * programmed with 0x3. (300 ns / 125 ns + 1) + * So, for I2C fast mode TRISE = FREQ[5:0] * 300 / 1000 + 1 + * + * Function stm32f4_i2c_set_periph_clk_freq made sure that parent rate + * is not higher than 46 MHz . As a result trise is at most 4 bits wide + * and so fits into the TRISE bits [5:0]. + */ + if (i2c_dev->speed == STM32_I2C_SPEED_STANDARD) + trise = freq + 1; + else + trise = freq * 3 / 10 + 1; + + writel_relaxed(STM32F4_I2C_TRISE_VALUE(trise), + i2c_dev->base + STM32F4_I2C_TRISE); +} + +static void stm32f4_i2c_set_speed_mode(struct stm32f4_i2c_dev *i2c_dev) +{ + u32 val; + u32 ccr = 0; + + if (i2c_dev->speed == STM32_I2C_SPEED_STANDARD) { + /* + * In standard mode: + * t_scl_high = t_scl_low = CCR * I2C parent clk period + * So to reach 100 kHz, we have: + * CCR = I2C parent rate / (100 kHz * 2) + * + * For example with parent rate = 2 MHz: + * CCR = 2000000 / (100000 * 2) = 10 + * t_scl_high = t_scl_low = 10 * (1 / 2000000) = 5000 ns + * t_scl_high + t_scl_low = 10000 ns so 100 kHz is reached + * + * Function stm32f4_i2c_set_periph_clk_freq made sure that + * parent rate is not higher than 46 MHz . As a result val + * is at most 8 bits wide and so fits into the CCR bits [11:0]. + */ + val = i2c_dev->parent_rate / (I2C_MAX_STANDARD_MODE_FREQ * 2); + } else { + /* + * In fast mode, we compute CCR with duty = 0 as with low + * frequencies we are not able to reach 400 kHz. + * In that case: + * t_scl_high = CCR * I2C parent clk period + * t_scl_low = 2 * CCR * I2C parent clk period + * So, CCR = I2C parent rate / (400 kHz * 3) + * + * For example with parent rate = 6 MHz: + * CCR = 6000000 / (400000 * 3) = 5 + * t_scl_high = 5 * (1 / 6000000) = 833 ns > 600 ns + * t_scl_low = 2 * 5 * (1 / 6000000) = 1667 ns > 1300 ns + * t_scl_high + t_scl_low = 2500 ns so 400 kHz is reached + * + * Function stm32f4_i2c_set_periph_clk_freq made sure that + * parent rate is not higher than 46 MHz . As a result val + * is at most 6 bits wide and so fits into the CCR bits [11:0]. + */ + val = DIV_ROUND_UP(i2c_dev->parent_rate, I2C_MAX_FAST_MODE_FREQ * 3); + + /* Select Fast mode */ + ccr |= STM32F4_I2C_CCR_FS; + } + + ccr |= STM32F4_I2C_CCR_CCR(val); + writel_relaxed(ccr, i2c_dev->base + STM32F4_I2C_CCR); +} + +/** + * stm32f4_i2c_hw_config() - Prepare I2C block + * @i2c_dev: Controller's private data + */ +static int stm32f4_i2c_hw_config(struct stm32f4_i2c_dev *i2c_dev) +{ + int ret; + + ret = stm32f4_i2c_set_periph_clk_freq(i2c_dev); + if (ret) + return ret; + + stm32f4_i2c_set_rise_time(i2c_dev); + + stm32f4_i2c_set_speed_mode(i2c_dev); + + /* Enable I2C */ + writel_relaxed(STM32F4_I2C_CR1_PE, i2c_dev->base + STM32F4_I2C_CR1); + + return 0; +} + +static int stm32f4_i2c_wait_free_bus(struct stm32f4_i2c_dev *i2c_dev) +{ + u32 status; + int ret; + + ret = readl_relaxed_poll_timeout(i2c_dev->base + STM32F4_I2C_SR2, + status, + !(status & STM32F4_I2C_SR2_BUSY), + 10, 1000); + if (ret) { + dev_dbg(i2c_dev->dev, "bus not free\n"); + ret = -EBUSY; + } + + return ret; +} + +/** + * stm32f4_i2c_write_byte() - Write a byte in the data register + * @i2c_dev: Controller's private data + * @byte: Data to write in the register + */ +static void stm32f4_i2c_write_byte(struct stm32f4_i2c_dev *i2c_dev, u8 byte) +{ + writel_relaxed(byte, i2c_dev->base + STM32F4_I2C_DR); +} + +/** + * stm32f4_i2c_write_msg() - Fill the data register in write mode + * @i2c_dev: Controller's private data + * + * This function fills the data register with I2C transfer buffer + */ +static void stm32f4_i2c_write_msg(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + + stm32f4_i2c_write_byte(i2c_dev, *msg->buf++); + msg->count--; +} + +static void stm32f4_i2c_read_msg(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + u32 rbuf; + + rbuf = readl_relaxed(i2c_dev->base + STM32F4_I2C_DR); + *msg->buf++ = rbuf; + msg->count--; +} + +static void stm32f4_i2c_terminate_xfer(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + void __iomem *reg; + + stm32f4_i2c_disable_irq(i2c_dev); + + reg = i2c_dev->base + STM32F4_I2C_CR1; + if (msg->stop) + stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_STOP); + else + stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_START); + + complete(&i2c_dev->complete); +} + +/** + * stm32f4_i2c_handle_write() - Handle FIFO empty interrupt in case of write + * @i2c_dev: Controller's private data + */ +static void stm32f4_i2c_handle_write(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR2; + + if (msg->count) { + stm32f4_i2c_write_msg(i2c_dev); + if (!msg->count) { + /* + * Disable buffer interrupts for RX not empty and TX + * empty events + */ + stm32f4_i2c_clr_bits(reg, STM32F4_I2C_CR2_ITBUFEN); + } + } else { + stm32f4_i2c_terminate_xfer(i2c_dev); + } +} + +/** + * stm32f4_i2c_handle_read() - Handle FIFO empty interrupt in case of read + * @i2c_dev: Controller's private data + * + * This function is called when a new data is received in data register + */ +static void stm32f4_i2c_handle_read(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR2; + + switch (msg->count) { + case 1: + stm32f4_i2c_disable_irq(i2c_dev); + stm32f4_i2c_read_msg(i2c_dev); + complete(&i2c_dev->complete); + break; + /* + * For 2-byte reception, 3-byte reception and for Data N-2, N-1 and N + * for N-byte reception with N > 3, we do not have to read the data + * register when RX not empty event occurs as we have to wait for byte + * transferred finished event before reading data. + * So, here we just disable buffer interrupt in order to avoid another + * system preemption due to RX not empty event. + */ + case 2: + case 3: + stm32f4_i2c_clr_bits(reg, STM32F4_I2C_CR2_ITBUFEN); + break; + /* + * For N byte reception with N > 3 we directly read data register + * until N-2 data. + */ + default: + stm32f4_i2c_read_msg(i2c_dev); + } +} + +/** + * stm32f4_i2c_handle_rx_done() - Handle byte transfer finished interrupt + * in case of read + * @i2c_dev: Controller's private data + * + * This function is called when a new data is received in the shift register + * but data register has not been read yet. + */ +static void stm32f4_i2c_handle_rx_done(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + void __iomem *reg; + u32 mask; + int i; + + switch (msg->count) { + case 2: + /* + * In order to correctly send the Stop or Repeated Start + * condition on the I2C bus, the STOP/START bit has to be set + * before reading the last two bytes (data N-1 and N). + * After that, we could read the last two bytes, disable + * remaining interrupts and notify the end of xfer to the + * client + */ + reg = i2c_dev->base + STM32F4_I2C_CR1; + if (msg->stop) + stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_STOP); + else + stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_START); + + for (i = 2; i > 0; i--) + stm32f4_i2c_read_msg(i2c_dev); + + reg = i2c_dev->base + STM32F4_I2C_CR2; + mask = STM32F4_I2C_CR2_ITEVTEN | STM32F4_I2C_CR2_ITERREN; + stm32f4_i2c_clr_bits(reg, mask); + + complete(&i2c_dev->complete); + break; + case 3: + /* + * In order to correctly generate the NACK pulse after the last + * received data byte, we have to enable NACK before reading N-2 + * data + */ + reg = i2c_dev->base + STM32F4_I2C_CR1; + stm32f4_i2c_clr_bits(reg, STM32F4_I2C_CR1_ACK); + stm32f4_i2c_read_msg(i2c_dev); + break; + default: + stm32f4_i2c_read_msg(i2c_dev); + } +} + +/** + * stm32f4_i2c_handle_rx_addr() - Handle address matched interrupt in case of + * master receiver + * @i2c_dev: Controller's private data + */ +static void stm32f4_i2c_handle_rx_addr(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + u32 cr1; + + switch (msg->count) { + case 0: + stm32f4_i2c_terminate_xfer(i2c_dev); + + /* Clear ADDR flag */ + readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2); + break; + case 1: + /* + * Single byte reception: + * Enable NACK and reset POS (Acknowledge position). + * Then, clear ADDR flag and set STOP or RepSTART. + * In that way, the NACK and STOP or RepStart pulses will be + * sent as soon as the byte will be received in shift register + */ + cr1 = readl_relaxed(i2c_dev->base + STM32F4_I2C_CR1); + cr1 &= ~(STM32F4_I2C_CR1_ACK | STM32F4_I2C_CR1_POS); + writel_relaxed(cr1, i2c_dev->base + STM32F4_I2C_CR1); + + readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2); + + if (msg->stop) + cr1 |= STM32F4_I2C_CR1_STOP; + else + cr1 |= STM32F4_I2C_CR1_START; + writel_relaxed(cr1, i2c_dev->base + STM32F4_I2C_CR1); + break; + case 2: + /* + * 2-byte reception: + * Enable NACK, set POS (NACK position) and clear ADDR flag. + * In that way, NACK will be sent for the next byte which will + * be received in the shift register instead of the current + * one. + */ + cr1 = readl_relaxed(i2c_dev->base + STM32F4_I2C_CR1); + cr1 &= ~STM32F4_I2C_CR1_ACK; + cr1 |= STM32F4_I2C_CR1_POS; + writel_relaxed(cr1, i2c_dev->base + STM32F4_I2C_CR1); + + readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2); + break; + + default: + /* + * N-byte reception: + * Enable ACK, reset POS (ACK position) and clear ADDR flag. + * In that way, ACK will be sent as soon as the current byte + * will be received in the shift register + */ + cr1 = readl_relaxed(i2c_dev->base + STM32F4_I2C_CR1); + cr1 |= STM32F4_I2C_CR1_ACK; + cr1 &= ~STM32F4_I2C_CR1_POS; + writel_relaxed(cr1, i2c_dev->base + STM32F4_I2C_CR1); + + readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2); + break; + } +} + +/** + * stm32f4_i2c_isr_event() - Interrupt routine for I2C bus event + * @irq: interrupt number + * @data: Controller's private data + */ +static irqreturn_t stm32f4_i2c_isr_event(int irq, void *data) +{ + struct stm32f4_i2c_dev *i2c_dev = data; + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + u32 possible_status = STM32F4_I2C_SR1_ITEVTEN_MASK; + u32 status, ien, event, cr2; + + cr2 = readl_relaxed(i2c_dev->base + STM32F4_I2C_CR2); + ien = cr2 & STM32F4_I2C_CR2_IRQ_MASK; + + /* Update possible_status if buffer interrupt is enabled */ + if (ien & STM32F4_I2C_CR2_ITBUFEN) + possible_status |= STM32F4_I2C_SR1_ITBUFEN_MASK; + + status = readl_relaxed(i2c_dev->base + STM32F4_I2C_SR1); + event = status & possible_status; + if (!event) { + dev_dbg(i2c_dev->dev, + "spurious evt irq (status=0x%08x, ien=0x%08x)\n", + status, ien); + return IRQ_NONE; + } + + /* Start condition generated */ + if (event & STM32F4_I2C_SR1_SB) + stm32f4_i2c_write_byte(i2c_dev, msg->addr); + + /* I2C Address sent */ + if (event & STM32F4_I2C_SR1_ADDR) { + if (msg->addr & I2C_M_RD) + stm32f4_i2c_handle_rx_addr(i2c_dev); + else + readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2); + + /* + * Enable buffer interrupts for RX not empty and TX empty + * events + */ + cr2 |= STM32F4_I2C_CR2_ITBUFEN; + writel_relaxed(cr2, i2c_dev->base + STM32F4_I2C_CR2); + } + + /* TX empty */ + if ((event & STM32F4_I2C_SR1_TXE) && !(msg->addr & I2C_M_RD)) + stm32f4_i2c_handle_write(i2c_dev); + + /* RX not empty */ + if ((event & STM32F4_I2C_SR1_RXNE) && (msg->addr & I2C_M_RD)) + stm32f4_i2c_handle_read(i2c_dev); + + /* + * The BTF (Byte Transfer finished) event occurs when: + * - in reception : a new byte is received in the shift register + * but the previous byte has not been read yet from data register + * - in transmission: a new byte should be sent but the data register + * has not been written yet + */ + if (event & STM32F4_I2C_SR1_BTF) { + if (msg->addr & I2C_M_RD) + stm32f4_i2c_handle_rx_done(i2c_dev); + else + stm32f4_i2c_handle_write(i2c_dev); + } + + return IRQ_HANDLED; +} + +/** + * stm32f4_i2c_isr_error() - Interrupt routine for I2C bus error + * @irq: interrupt number + * @data: Controller's private data + */ +static irqreturn_t stm32f4_i2c_isr_error(int irq, void *data) +{ + struct stm32f4_i2c_dev *i2c_dev = data; + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + void __iomem *reg; + u32 status; + + status = readl_relaxed(i2c_dev->base + STM32F4_I2C_SR1); + + /* Arbitration lost */ + if (status & STM32F4_I2C_SR1_ARLO) { + status &= ~STM32F4_I2C_SR1_ARLO; + writel_relaxed(status, i2c_dev->base + STM32F4_I2C_SR1); + msg->result = -EAGAIN; + } + + /* + * Acknowledge failure: + * In master transmitter mode a Stop must be generated by software + */ + if (status & STM32F4_I2C_SR1_AF) { + if (!(msg->addr & I2C_M_RD)) { + reg = i2c_dev->base + STM32F4_I2C_CR1; + stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_STOP); + } + status &= ~STM32F4_I2C_SR1_AF; + writel_relaxed(status, i2c_dev->base + STM32F4_I2C_SR1); + msg->result = -EIO; + } + + /* Bus error */ + if (status & STM32F4_I2C_SR1_BERR) { + status &= ~STM32F4_I2C_SR1_BERR; + writel_relaxed(status, i2c_dev->base + STM32F4_I2C_SR1); + msg->result = -EIO; + } + + stm32f4_i2c_disable_irq(i2c_dev); + complete(&i2c_dev->complete); + + return IRQ_HANDLED; +} + +/** + * stm32f4_i2c_xfer_msg() - Transfer a single I2C message + * @i2c_dev: Controller's private data + * @msg: I2C message to transfer + * @is_first: first message of the sequence + * @is_last: last message of the sequence + */ +static int stm32f4_i2c_xfer_msg(struct stm32f4_i2c_dev *i2c_dev, + struct i2c_msg *msg, bool is_first, + bool is_last) +{ + struct stm32f4_i2c_msg *f4_msg = &i2c_dev->msg; + void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR1; + unsigned long timeout; + u32 mask; + int ret; + + f4_msg->addr = i2c_8bit_addr_from_msg(msg); + f4_msg->buf = msg->buf; + f4_msg->count = msg->len; + f4_msg->result = 0; + f4_msg->stop = is_last; + + reinit_completion(&i2c_dev->complete); + + /* Enable events and errors interrupts */ + mask = STM32F4_I2C_CR2_ITEVTEN | STM32F4_I2C_CR2_ITERREN; + stm32f4_i2c_set_bits(i2c_dev->base + STM32F4_I2C_CR2, mask); + + if (is_first) { + ret = stm32f4_i2c_wait_free_bus(i2c_dev); + if (ret) + return ret; + + /* START generation */ + stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_START); + } + + timeout = wait_for_completion_timeout(&i2c_dev->complete, + i2c_dev->adap.timeout); + ret = f4_msg->result; + + if (!timeout) + ret = -ETIMEDOUT; + + return ret; +} + +/** + * stm32f4_i2c_xfer() - Transfer combined I2C message + * @i2c_adap: Adapter pointer to the controller + * @msgs: Pointer to data to be written. + * @num: Number of messages to be executed + */ +static int stm32f4_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], + int num) +{ + struct stm32f4_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap); + int ret, i; + + ret = clk_enable(i2c_dev->clk); + if (ret) { + dev_err(i2c_dev->dev, "Failed to enable clock\n"); + return ret; + } + + for (i = 0; i < num && !ret; i++) + ret = stm32f4_i2c_xfer_msg(i2c_dev, &msgs[i], i == 0, + i == num - 1); + + clk_disable(i2c_dev->clk); + + return (ret < 0) ? ret : num; +} + +static u32 stm32f4_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm stm32f4_i2c_algo = { + .master_xfer = stm32f4_i2c_xfer, + .functionality = stm32f4_i2c_func, +}; + +static int stm32f4_i2c_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct stm32f4_i2c_dev *i2c_dev; + struct resource *res; + u32 irq_event, irq_error, clk_rate; + struct i2c_adapter *adap; + struct reset_control *rst; + int ret; + + i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); + if (!i2c_dev) + return -ENOMEM; + + i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(i2c_dev->base)) + return PTR_ERR(i2c_dev->base); + + irq_event = irq_of_parse_and_map(np, 0); + if (!irq_event) { + dev_err(&pdev->dev, "IRQ event missing or invalid\n"); + return -EINVAL; + } + + irq_error = irq_of_parse_and_map(np, 1); + if (!irq_error) { + dev_err(&pdev->dev, "IRQ error missing or invalid\n"); + return -EINVAL; + } + + i2c_dev->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(i2c_dev->clk)) { + dev_err(&pdev->dev, "Error: Missing controller clock\n"); + return PTR_ERR(i2c_dev->clk); + } + ret = clk_prepare_enable(i2c_dev->clk); + if (ret) { + dev_err(i2c_dev->dev, "Failed to prepare_enable clock\n"); + return ret; + } + + rst = devm_reset_control_get_exclusive(&pdev->dev, NULL); + if (IS_ERR(rst)) { + ret = dev_err_probe(&pdev->dev, PTR_ERR(rst), + "Error: Missing reset ctrl\n"); + goto clk_free; + } + reset_control_assert(rst); + udelay(2); + reset_control_deassert(rst); + + i2c_dev->speed = STM32_I2C_SPEED_STANDARD; + ret = of_property_read_u32(np, "clock-frequency", &clk_rate); + if (!ret && clk_rate >= I2C_MAX_FAST_MODE_FREQ) + i2c_dev->speed = STM32_I2C_SPEED_FAST; + + i2c_dev->dev = &pdev->dev; + + ret = devm_request_irq(&pdev->dev, irq_event, stm32f4_i2c_isr_event, 0, + pdev->name, i2c_dev); + if (ret) { + dev_err(&pdev->dev, "Failed to request irq event %i\n", + irq_event); + goto clk_free; + } + + ret = devm_request_irq(&pdev->dev, irq_error, stm32f4_i2c_isr_error, 0, + pdev->name, i2c_dev); + if (ret) { + dev_err(&pdev->dev, "Failed to request irq error %i\n", + irq_error); + goto clk_free; + } + + ret = stm32f4_i2c_hw_config(i2c_dev); + if (ret) + goto clk_free; + + adap = &i2c_dev->adap; + i2c_set_adapdata(adap, i2c_dev); + snprintf(adap->name, sizeof(adap->name), "STM32 I2C(%pa)", &res->start); + adap->owner = THIS_MODULE; + adap->timeout = 2 * HZ; + adap->retries = 0; + adap->algo = &stm32f4_i2c_algo; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + + init_completion(&i2c_dev->complete); + + ret = i2c_add_adapter(adap); + if (ret) + goto clk_free; + + platform_set_drvdata(pdev, i2c_dev); + + clk_disable(i2c_dev->clk); + + dev_info(i2c_dev->dev, "STM32F4 I2C driver registered\n"); + + return 0; + +clk_free: + clk_disable_unprepare(i2c_dev->clk); + return ret; +} + +static void stm32f4_i2c_remove(struct platform_device *pdev) +{ + struct stm32f4_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c_dev->adap); + + clk_unprepare(i2c_dev->clk); +} + +static const struct of_device_id stm32f4_i2c_match[] = { + { .compatible = "st,stm32f4-i2c", }, + {}, +}; +MODULE_DEVICE_TABLE(of, stm32f4_i2c_match); + +static struct platform_driver stm32f4_i2c_driver = { + .driver = { + .name = "stm32f4-i2c", + .of_match_table = stm32f4_i2c_match, + }, + .probe = stm32f4_i2c_probe, + .remove_new = stm32f4_i2c_remove, +}; + +module_platform_driver(stm32f4_i2c_driver); + +MODULE_AUTHOR("M'boumba Cedric Madianga <cedric.madianga@gmail.com>"); +MODULE_DESCRIPTION("STMicroelectronics STM32F4 I2C driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c new file mode 100644 index 000000000..0d3c9a041 --- /dev/null +++ b/drivers/i2c/busses/i2c-stm32f7.c @@ -0,0 +1,2497 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for STMicroelectronics STM32F7 I2C controller + * + * This I2C controller is described in the STM32F75xxx and STM32F74xxx Soc + * reference manual. + * Please see below a link to the documentation: + * http://www.st.com/resource/en/reference_manual/dm00124865.pdf + * + * Copyright (C) M'boumba Cedric Madianga 2017 + * Copyright (C) STMicroelectronics 2017 + * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com> + * + * This driver is based on i2c-stm32f4.c + * + */ +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/i2c-smbus.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/pinctrl/consumer.h> +#include <linux/pm_runtime.h> +#include <linux/pm_wakeirq.h> +#include <linux/regmap.h> +#include <linux/reset.h> +#include <linux/slab.h> + +#include "i2c-stm32.h" + +/* STM32F7 I2C registers */ +#define STM32F7_I2C_CR1 0x00 +#define STM32F7_I2C_CR2 0x04 +#define STM32F7_I2C_OAR1 0x08 +#define STM32F7_I2C_OAR2 0x0C +#define STM32F7_I2C_PECR 0x20 +#define STM32F7_I2C_TIMINGR 0x10 +#define STM32F7_I2C_ISR 0x18 +#define STM32F7_I2C_ICR 0x1C +#define STM32F7_I2C_RXDR 0x24 +#define STM32F7_I2C_TXDR 0x28 + +/* STM32F7 I2C control 1 */ +#define STM32F7_I2C_CR1_PECEN BIT(23) +#define STM32F7_I2C_CR1_ALERTEN BIT(22) +#define STM32F7_I2C_CR1_SMBHEN BIT(20) +#define STM32F7_I2C_CR1_WUPEN BIT(18) +#define STM32F7_I2C_CR1_SBC BIT(16) +#define STM32F7_I2C_CR1_RXDMAEN BIT(15) +#define STM32F7_I2C_CR1_TXDMAEN BIT(14) +#define STM32F7_I2C_CR1_ANFOFF BIT(12) +#define STM32F7_I2C_CR1_DNF_MASK GENMASK(11, 8) +#define STM32F7_I2C_CR1_DNF(n) (((n) & 0xf) << 8) +#define STM32F7_I2C_CR1_ERRIE BIT(7) +#define STM32F7_I2C_CR1_TCIE BIT(6) +#define STM32F7_I2C_CR1_STOPIE BIT(5) +#define STM32F7_I2C_CR1_NACKIE BIT(4) +#define STM32F7_I2C_CR1_ADDRIE BIT(3) +#define STM32F7_I2C_CR1_RXIE BIT(2) +#define STM32F7_I2C_CR1_TXIE BIT(1) +#define STM32F7_I2C_CR1_PE BIT(0) +#define STM32F7_I2C_ALL_IRQ_MASK (STM32F7_I2C_CR1_ERRIE \ + | STM32F7_I2C_CR1_TCIE \ + | STM32F7_I2C_CR1_STOPIE \ + | STM32F7_I2C_CR1_NACKIE \ + | STM32F7_I2C_CR1_RXIE \ + | STM32F7_I2C_CR1_TXIE) +#define STM32F7_I2C_XFER_IRQ_MASK (STM32F7_I2C_CR1_TCIE \ + | STM32F7_I2C_CR1_STOPIE \ + | STM32F7_I2C_CR1_NACKIE \ + | STM32F7_I2C_CR1_RXIE \ + | STM32F7_I2C_CR1_TXIE) + +/* STM32F7 I2C control 2 */ +#define STM32F7_I2C_CR2_PECBYTE BIT(26) +#define STM32F7_I2C_CR2_RELOAD BIT(24) +#define STM32F7_I2C_CR2_NBYTES_MASK GENMASK(23, 16) +#define STM32F7_I2C_CR2_NBYTES(n) (((n) & 0xff) << 16) +#define STM32F7_I2C_CR2_NACK BIT(15) +#define STM32F7_I2C_CR2_STOP BIT(14) +#define STM32F7_I2C_CR2_START BIT(13) +#define STM32F7_I2C_CR2_HEAD10R BIT(12) +#define STM32F7_I2C_CR2_ADD10 BIT(11) +#define STM32F7_I2C_CR2_RD_WRN BIT(10) +#define STM32F7_I2C_CR2_SADD10_MASK GENMASK(9, 0) +#define STM32F7_I2C_CR2_SADD10(n) (((n) & \ + STM32F7_I2C_CR2_SADD10_MASK)) +#define STM32F7_I2C_CR2_SADD7_MASK GENMASK(7, 1) +#define STM32F7_I2C_CR2_SADD7(n) (((n) & 0x7f) << 1) + +/* STM32F7 I2C Own Address 1 */ +#define STM32F7_I2C_OAR1_OA1EN BIT(15) +#define STM32F7_I2C_OAR1_OA1MODE BIT(10) +#define STM32F7_I2C_OAR1_OA1_10_MASK GENMASK(9, 0) +#define STM32F7_I2C_OAR1_OA1_10(n) (((n) & \ + STM32F7_I2C_OAR1_OA1_10_MASK)) +#define STM32F7_I2C_OAR1_OA1_7_MASK GENMASK(7, 1) +#define STM32F7_I2C_OAR1_OA1_7(n) (((n) & 0x7f) << 1) +#define STM32F7_I2C_OAR1_MASK (STM32F7_I2C_OAR1_OA1_7_MASK \ + | STM32F7_I2C_OAR1_OA1_10_MASK \ + | STM32F7_I2C_OAR1_OA1EN \ + | STM32F7_I2C_OAR1_OA1MODE) + +/* STM32F7 I2C Own Address 2 */ +#define STM32F7_I2C_OAR2_OA2EN BIT(15) +#define STM32F7_I2C_OAR2_OA2MSK_MASK GENMASK(10, 8) +#define STM32F7_I2C_OAR2_OA2MSK(n) (((n) & 0x7) << 8) +#define STM32F7_I2C_OAR2_OA2_7_MASK GENMASK(7, 1) +#define STM32F7_I2C_OAR2_OA2_7(n) (((n) & 0x7f) << 1) +#define STM32F7_I2C_OAR2_MASK (STM32F7_I2C_OAR2_OA2MSK_MASK \ + | STM32F7_I2C_OAR2_OA2_7_MASK \ + | STM32F7_I2C_OAR2_OA2EN) + +/* STM32F7 I2C Interrupt Status */ +#define STM32F7_I2C_ISR_ADDCODE_MASK GENMASK(23, 17) +#define STM32F7_I2C_ISR_ADDCODE_GET(n) \ + (((n) & STM32F7_I2C_ISR_ADDCODE_MASK) >> 17) +#define STM32F7_I2C_ISR_DIR BIT(16) +#define STM32F7_I2C_ISR_BUSY BIT(15) +#define STM32F7_I2C_ISR_ALERT BIT(13) +#define STM32F7_I2C_ISR_PECERR BIT(11) +#define STM32F7_I2C_ISR_ARLO BIT(9) +#define STM32F7_I2C_ISR_BERR BIT(8) +#define STM32F7_I2C_ISR_TCR BIT(7) +#define STM32F7_I2C_ISR_TC BIT(6) +#define STM32F7_I2C_ISR_STOPF BIT(5) +#define STM32F7_I2C_ISR_NACKF BIT(4) +#define STM32F7_I2C_ISR_ADDR BIT(3) +#define STM32F7_I2C_ISR_RXNE BIT(2) +#define STM32F7_I2C_ISR_TXIS BIT(1) +#define STM32F7_I2C_ISR_TXE BIT(0) + +/* STM32F7 I2C Interrupt Clear */ +#define STM32F7_I2C_ICR_ALERTCF BIT(13) +#define STM32F7_I2C_ICR_PECCF BIT(11) +#define STM32F7_I2C_ICR_ARLOCF BIT(9) +#define STM32F7_I2C_ICR_BERRCF BIT(8) +#define STM32F7_I2C_ICR_STOPCF BIT(5) +#define STM32F7_I2C_ICR_NACKCF BIT(4) +#define STM32F7_I2C_ICR_ADDRCF BIT(3) + +/* STM32F7 I2C Timing */ +#define STM32F7_I2C_TIMINGR_PRESC(n) (((n) & 0xf) << 28) +#define STM32F7_I2C_TIMINGR_SCLDEL(n) (((n) & 0xf) << 20) +#define STM32F7_I2C_TIMINGR_SDADEL(n) (((n) & 0xf) << 16) +#define STM32F7_I2C_TIMINGR_SCLH(n) (((n) & 0xff) << 8) +#define STM32F7_I2C_TIMINGR_SCLL(n) ((n) & 0xff) + +#define STM32F7_I2C_MAX_LEN 0xff +#define STM32F7_I2C_DMA_LEN_MIN 0x16 +enum { + STM32F7_SLAVE_HOSTNOTIFY, + STM32F7_SLAVE_7_10_BITS_ADDR, + STM32F7_SLAVE_7_BITS_ADDR, + STM32F7_I2C_MAX_SLAVE +}; + +#define STM32F7_I2C_DNF_DEFAULT 0 +#define STM32F7_I2C_DNF_MAX 15 + +#define STM32F7_I2C_ANALOG_FILTER_DELAY_MIN 50 /* ns */ +#define STM32F7_I2C_ANALOG_FILTER_DELAY_MAX 260 /* ns */ + +#define STM32F7_I2C_RISE_TIME_DEFAULT 25 /* ns */ +#define STM32F7_I2C_FALL_TIME_DEFAULT 10 /* ns */ + +#define STM32F7_PRESC_MAX BIT(4) +#define STM32F7_SCLDEL_MAX BIT(4) +#define STM32F7_SDADEL_MAX BIT(4) +#define STM32F7_SCLH_MAX BIT(8) +#define STM32F7_SCLL_MAX BIT(8) + +#define STM32F7_AUTOSUSPEND_DELAY (HZ / 100) + +/** + * struct stm32f7_i2c_regs - i2c f7 registers backup + * @cr1: Control register 1 + * @cr2: Control register 2 + * @oar1: Own address 1 register + * @oar2: Own address 2 register + * @tmgr: Timing register + */ +struct stm32f7_i2c_regs { + u32 cr1; + u32 cr2; + u32 oar1; + u32 oar2; + u32 tmgr; +}; + +/** + * struct stm32f7_i2c_spec - private i2c specification timing + * @rate: I2C bus speed (Hz) + * @fall_max: Max fall time of both SDA and SCL signals (ns) + * @rise_max: Max rise time of both SDA and SCL signals (ns) + * @hddat_min: Min data hold time (ns) + * @vddat_max: Max data valid time (ns) + * @sudat_min: Min data setup time (ns) + * @l_min: Min low period of the SCL clock (ns) + * @h_min: Min high period of the SCL clock (ns) + */ +struct stm32f7_i2c_spec { + u32 rate; + u32 fall_max; + u32 rise_max; + u32 hddat_min; + u32 vddat_max; + u32 sudat_min; + u32 l_min; + u32 h_min; +}; + +/** + * struct stm32f7_i2c_setup - private I2C timing setup parameters + * @speed_freq: I2C speed frequency (Hz) + * @clock_src: I2C clock source frequency (Hz) + * @rise_time: Rise time (ns) + * @fall_time: Fall time (ns) + * @fmp_clr_offset: Fast Mode Plus clear register offset from set register + */ +struct stm32f7_i2c_setup { + u32 speed_freq; + u32 clock_src; + u32 rise_time; + u32 fall_time; + u32 fmp_clr_offset; +}; + +/** + * struct stm32f7_i2c_timings - private I2C output parameters + * @node: List entry + * @presc: Prescaler value + * @scldel: Data setup time + * @sdadel: Data hold time + * @sclh: SCL high period (master mode) + * @scll: SCL low period (master mode) + */ +struct stm32f7_i2c_timings { + struct list_head node; + u8 presc; + u8 scldel; + u8 sdadel; + u8 sclh; + u8 scll; +}; + +/** + * struct stm32f7_i2c_msg - client specific data + * @addr: 8-bit or 10-bit slave addr, including r/w bit + * @count: number of bytes to be transferred + * @buf: data buffer + * @result: result of the transfer + * @stop: last I2C msg to be sent, i.e. STOP to be generated + * @smbus: boolean to know if the I2C IP is used in SMBus mode + * @size: type of SMBus protocol + * @read_write: direction of SMBus protocol + * SMBus block read and SMBus block write - block read process call protocols + * @smbus_buf: buffer to be used for SMBus protocol transfer. It will + * contain a maximum of 32 bytes of data + byte command + byte count + PEC + * This buffer has to be 32-bit aligned to be compliant with memory address + * register in DMA mode. + */ +struct stm32f7_i2c_msg { + u16 addr; + u32 count; + u8 *buf; + int result; + bool stop; + bool smbus; + int size; + char read_write; + u8 smbus_buf[I2C_SMBUS_BLOCK_MAX + 3] __aligned(4); +}; + +/** + * struct stm32f7_i2c_alert - SMBus alert specific data + * @setup: platform data for the smbus_alert i2c client + * @ara: I2C slave device used to respond to the SMBus Alert with Alert + * Response Address + */ +struct stm32f7_i2c_alert { + struct i2c_smbus_alert_setup setup; + struct i2c_client *ara; +}; + +/** + * struct stm32f7_i2c_dev - private data of the controller + * @adap: I2C adapter for this controller + * @dev: device for this controller + * @base: virtual memory area + * @complete: completion of I2C message + * @clk: hw i2c clock + * @bus_rate: I2C clock frequency of the controller + * @msg: Pointer to data to be written + * @msg_num: number of I2C messages to be executed + * @msg_id: message identifiant + * @f7_msg: customized i2c msg for driver usage + * @setup: I2C timing input setup + * @timing: I2C computed timings + * @slave: list of slave devices registered on the I2C bus + * @slave_running: slave device currently used + * @backup_regs: backup of i2c controller registers (for suspend/resume) + * @slave_dir: transfer direction for the current slave device + * @master_mode: boolean to know in which mode the I2C is running (master or + * slave) + * @dma: dma data + * @use_dma: boolean to know if dma is used in the current transfer + * @regmap: holds SYSCFG phandle for Fast Mode Plus bits + * @fmp_sreg: register address for setting Fast Mode Plus bits + * @fmp_creg: register address for clearing Fast Mode Plus bits + * @fmp_mask: mask for Fast Mode Plus bits in set register + * @wakeup_src: boolean to know if the device is a wakeup source + * @smbus_mode: states that the controller is configured in SMBus mode + * @host_notify_client: SMBus host-notify client + * @analog_filter: boolean to indicate enabling of the analog filter + * @dnf_dt: value of digital filter requested via dt + * @dnf: value of digital filter to apply + * @alert: SMBus alert specific data + */ +struct stm32f7_i2c_dev { + struct i2c_adapter adap; + struct device *dev; + void __iomem *base; + struct completion complete; + struct clk *clk; + unsigned int bus_rate; + struct i2c_msg *msg; + unsigned int msg_num; + unsigned int msg_id; + struct stm32f7_i2c_msg f7_msg; + struct stm32f7_i2c_setup setup; + struct stm32f7_i2c_timings timing; + struct i2c_client *slave[STM32F7_I2C_MAX_SLAVE]; + struct i2c_client *slave_running; + struct stm32f7_i2c_regs backup_regs; + u32 slave_dir; + bool master_mode; + struct stm32_i2c_dma *dma; + bool use_dma; + struct regmap *regmap; + u32 fmp_sreg; + u32 fmp_creg; + u32 fmp_mask; + bool wakeup_src; + bool smbus_mode; + struct i2c_client *host_notify_client; + bool analog_filter; + u32 dnf_dt; + u32 dnf; + struct stm32f7_i2c_alert *alert; +}; + +/* + * All these values are coming from I2C Specification, Version 6.0, 4th of + * April 2014. + * + * Table10. Characteristics of the SDA and SCL bus lines for Standard, Fast, + * and Fast-mode Plus I2C-bus devices + */ +static struct stm32f7_i2c_spec stm32f7_i2c_specs[] = { + { + .rate = I2C_MAX_STANDARD_MODE_FREQ, + .fall_max = 300, + .rise_max = 1000, + .hddat_min = 0, + .vddat_max = 3450, + .sudat_min = 250, + .l_min = 4700, + .h_min = 4000, + }, + { + .rate = I2C_MAX_FAST_MODE_FREQ, + .fall_max = 300, + .rise_max = 300, + .hddat_min = 0, + .vddat_max = 900, + .sudat_min = 100, + .l_min = 1300, + .h_min = 600, + }, + { + .rate = I2C_MAX_FAST_MODE_PLUS_FREQ, + .fall_max = 100, + .rise_max = 120, + .hddat_min = 0, + .vddat_max = 450, + .sudat_min = 50, + .l_min = 500, + .h_min = 260, + }, +}; + +static const struct stm32f7_i2c_setup stm32f7_setup = { + .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT, + .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT, +}; + +static const struct stm32f7_i2c_setup stm32mp15_setup = { + .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT, + .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT, + .fmp_clr_offset = 0x40, +}; + +static const struct stm32f7_i2c_setup stm32mp13_setup = { + .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT, + .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT, + .fmp_clr_offset = 0x4, +}; + +static inline void stm32f7_i2c_set_bits(void __iomem *reg, u32 mask) +{ + writel_relaxed(readl_relaxed(reg) | mask, reg); +} + +static inline void stm32f7_i2c_clr_bits(void __iomem *reg, u32 mask) +{ + writel_relaxed(readl_relaxed(reg) & ~mask, reg); +} + +static void stm32f7_i2c_disable_irq(struct stm32f7_i2c_dev *i2c_dev, u32 mask) +{ + stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, mask); +} + +static struct stm32f7_i2c_spec *stm32f7_get_specs(u32 rate) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(stm32f7_i2c_specs); i++) + if (rate <= stm32f7_i2c_specs[i].rate) + return &stm32f7_i2c_specs[i]; + + return ERR_PTR(-EINVAL); +} + +#define RATE_MIN(rate) ((rate) * 8 / 10) +static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev, + struct stm32f7_i2c_setup *setup, + struct stm32f7_i2c_timings *output) +{ + struct stm32f7_i2c_spec *specs; + u32 p_prev = STM32F7_PRESC_MAX; + u32 i2cclk = DIV_ROUND_CLOSEST(NSEC_PER_SEC, + setup->clock_src); + u32 i2cbus = DIV_ROUND_CLOSEST(NSEC_PER_SEC, + setup->speed_freq); + u32 clk_error_prev = i2cbus; + u32 tsync; + u32 af_delay_min, af_delay_max; + u32 dnf_delay; + u32 clk_min, clk_max; + int sdadel_min, sdadel_max; + int scldel_min; + struct stm32f7_i2c_timings *v, *_v, *s; + struct list_head solutions; + u16 p, l, a, h; + int ret = 0; + + specs = stm32f7_get_specs(setup->speed_freq); + if (specs == ERR_PTR(-EINVAL)) { + dev_err(i2c_dev->dev, "speed out of bound {%d}\n", + setup->speed_freq); + return -EINVAL; + } + + if ((setup->rise_time > specs->rise_max) || + (setup->fall_time > specs->fall_max)) { + dev_err(i2c_dev->dev, + "timings out of bound Rise{%d>%d}/Fall{%d>%d}\n", + setup->rise_time, specs->rise_max, + setup->fall_time, specs->fall_max); + return -EINVAL; + } + + i2c_dev->dnf = DIV_ROUND_CLOSEST(i2c_dev->dnf_dt, i2cclk); + if (i2c_dev->dnf > STM32F7_I2C_DNF_MAX) { + dev_err(i2c_dev->dev, + "DNF out of bound %d/%d\n", + i2c_dev->dnf * i2cclk, STM32F7_I2C_DNF_MAX * i2cclk); + return -EINVAL; + } + + /* Analog and Digital Filters */ + af_delay_min = + (i2c_dev->analog_filter ? + STM32F7_I2C_ANALOG_FILTER_DELAY_MIN : 0); + af_delay_max = + (i2c_dev->analog_filter ? + STM32F7_I2C_ANALOG_FILTER_DELAY_MAX : 0); + dnf_delay = i2c_dev->dnf * i2cclk; + + sdadel_min = specs->hddat_min + setup->fall_time - + af_delay_min - (i2c_dev->dnf + 3) * i2cclk; + + sdadel_max = specs->vddat_max - setup->rise_time - + af_delay_max - (i2c_dev->dnf + 4) * i2cclk; + + scldel_min = setup->rise_time + specs->sudat_min; + + if (sdadel_min < 0) + sdadel_min = 0; + if (sdadel_max < 0) + sdadel_max = 0; + + dev_dbg(i2c_dev->dev, "SDADEL(min/max): %i/%i, SCLDEL(Min): %i\n", + sdadel_min, sdadel_max, scldel_min); + + INIT_LIST_HEAD(&solutions); + /* Compute possible values for PRESC, SCLDEL and SDADEL */ + for (p = 0; p < STM32F7_PRESC_MAX; p++) { + for (l = 0; l < STM32F7_SCLDEL_MAX; l++) { + u32 scldel = (l + 1) * (p + 1) * i2cclk; + + if (scldel < scldel_min) + continue; + + for (a = 0; a < STM32F7_SDADEL_MAX; a++) { + u32 sdadel = (a * (p + 1) + 1) * i2cclk; + + if (((sdadel >= sdadel_min) && + (sdadel <= sdadel_max)) && + (p != p_prev)) { + v = kmalloc(sizeof(*v), GFP_KERNEL); + if (!v) { + ret = -ENOMEM; + goto exit; + } + + v->presc = p; + v->scldel = l; + v->sdadel = a; + p_prev = p; + + list_add_tail(&v->node, + &solutions); + break; + } + } + + if (p_prev == p) + break; + } + } + + if (list_empty(&solutions)) { + dev_err(i2c_dev->dev, "no Prescaler solution\n"); + ret = -EPERM; + goto exit; + } + + tsync = af_delay_min + dnf_delay + (2 * i2cclk); + s = NULL; + clk_max = NSEC_PER_SEC / RATE_MIN(setup->speed_freq); + clk_min = NSEC_PER_SEC / setup->speed_freq; + + /* + * Among Prescaler possibilities discovered above figures out SCL Low + * and High Period. Provided: + * - SCL Low Period has to be higher than SCL Clock Low Period + * defined by I2C Specification. I2C Clock has to be lower than + * (SCL Low Period - Analog/Digital filters) / 4. + * - SCL High Period has to be lower than SCL Clock High Period + * defined by I2C Specification + * - I2C Clock has to be lower than SCL High Period + */ + list_for_each_entry(v, &solutions, node) { + u32 prescaler = (v->presc + 1) * i2cclk; + + for (l = 0; l < STM32F7_SCLL_MAX; l++) { + u32 tscl_l = (l + 1) * prescaler + tsync; + + if ((tscl_l < specs->l_min) || + (i2cclk >= + ((tscl_l - af_delay_min - dnf_delay) / 4))) { + continue; + } + + for (h = 0; h < STM32F7_SCLH_MAX; h++) { + u32 tscl_h = (h + 1) * prescaler + tsync; + u32 tscl = tscl_l + tscl_h + + setup->rise_time + setup->fall_time; + + if ((tscl >= clk_min) && (tscl <= clk_max) && + (tscl_h >= specs->h_min) && + (i2cclk < tscl_h)) { + int clk_error = tscl - i2cbus; + + if (clk_error < 0) + clk_error = -clk_error; + + if (clk_error < clk_error_prev) { + clk_error_prev = clk_error; + v->scll = l; + v->sclh = h; + s = v; + } + } + } + } + } + + if (!s) { + dev_err(i2c_dev->dev, "no solution at all\n"); + ret = -EPERM; + goto exit; + } + + output->presc = s->presc; + output->scldel = s->scldel; + output->sdadel = s->sdadel; + output->scll = s->scll; + output->sclh = s->sclh; + + dev_dbg(i2c_dev->dev, + "Presc: %i, scldel: %i, sdadel: %i, scll: %i, sclh: %i\n", + output->presc, + output->scldel, output->sdadel, + output->scll, output->sclh); + +exit: + /* Release list and memory */ + list_for_each_entry_safe(v, _v, &solutions, node) { + list_del(&v->node); + kfree(v); + } + + return ret; +} + +static u32 stm32f7_get_lower_rate(u32 rate) +{ + int i = ARRAY_SIZE(stm32f7_i2c_specs); + + while (--i) + if (stm32f7_i2c_specs[i].rate < rate) + break; + + return stm32f7_i2c_specs[i].rate; +} + +static int stm32f7_i2c_setup_timing(struct stm32f7_i2c_dev *i2c_dev, + struct stm32f7_i2c_setup *setup) +{ + struct i2c_timings timings, *t = &timings; + int ret = 0; + + t->bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ; + t->scl_rise_ns = i2c_dev->setup.rise_time; + t->scl_fall_ns = i2c_dev->setup.fall_time; + + i2c_parse_fw_timings(i2c_dev->dev, t, false); + + if (t->bus_freq_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) { + dev_err(i2c_dev->dev, "Invalid bus speed (%i>%i)\n", + t->bus_freq_hz, I2C_MAX_FAST_MODE_PLUS_FREQ); + return -EINVAL; + } + + setup->speed_freq = t->bus_freq_hz; + i2c_dev->setup.rise_time = t->scl_rise_ns; + i2c_dev->setup.fall_time = t->scl_fall_ns; + i2c_dev->dnf_dt = t->digital_filter_width_ns; + setup->clock_src = clk_get_rate(i2c_dev->clk); + + if (!setup->clock_src) { + dev_err(i2c_dev->dev, "clock rate is 0\n"); + return -EINVAL; + } + + if (!of_property_read_bool(i2c_dev->dev->of_node, "i2c-digital-filter")) + i2c_dev->dnf_dt = STM32F7_I2C_DNF_DEFAULT; + + do { + ret = stm32f7_i2c_compute_timing(i2c_dev, setup, + &i2c_dev->timing); + if (ret) { + dev_err(i2c_dev->dev, + "failed to compute I2C timings.\n"); + if (setup->speed_freq <= I2C_MAX_STANDARD_MODE_FREQ) + break; + setup->speed_freq = + stm32f7_get_lower_rate(setup->speed_freq); + dev_warn(i2c_dev->dev, + "downgrade I2C Speed Freq to (%i)\n", + setup->speed_freq); + } + } while (ret); + + if (ret) { + dev_err(i2c_dev->dev, "Impossible to compute I2C timings.\n"); + return ret; + } + + i2c_dev->analog_filter = of_property_read_bool(i2c_dev->dev->of_node, + "i2c-analog-filter"); + + dev_dbg(i2c_dev->dev, "I2C Speed(%i), Clk Source(%i)\n", + setup->speed_freq, setup->clock_src); + dev_dbg(i2c_dev->dev, "I2C Rise(%i) and Fall(%i) Time\n", + setup->rise_time, setup->fall_time); + dev_dbg(i2c_dev->dev, "I2C Analog Filter(%s), DNF(%i)\n", + (i2c_dev->analog_filter ? "On" : "Off"), i2c_dev->dnf); + + i2c_dev->bus_rate = setup->speed_freq; + + return 0; +} + +static void stm32f7_i2c_disable_dma_req(struct stm32f7_i2c_dev *i2c_dev) +{ + void __iomem *base = i2c_dev->base; + u32 mask = STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN; + + stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask); +} + +static void stm32f7_i2c_dma_callback(void *arg) +{ + struct stm32f7_i2c_dev *i2c_dev = (struct stm32f7_i2c_dev *)arg; + struct stm32_i2c_dma *dma = i2c_dev->dma; + struct device *dev = dma->chan_using->device->dev; + + stm32f7_i2c_disable_dma_req(i2c_dev); + dma_unmap_single(dev, dma->dma_buf, dma->dma_len, dma->dma_data_dir); + complete(&dma->dma_complete); +} + +static void stm32f7_i2c_hw_config(struct stm32f7_i2c_dev *i2c_dev) +{ + struct stm32f7_i2c_timings *t = &i2c_dev->timing; + u32 timing = 0; + + /* Timing settings */ + timing |= STM32F7_I2C_TIMINGR_PRESC(t->presc); + timing |= STM32F7_I2C_TIMINGR_SCLDEL(t->scldel); + timing |= STM32F7_I2C_TIMINGR_SDADEL(t->sdadel); + timing |= STM32F7_I2C_TIMINGR_SCLH(t->sclh); + timing |= STM32F7_I2C_TIMINGR_SCLL(t->scll); + writel_relaxed(timing, i2c_dev->base + STM32F7_I2C_TIMINGR); + + /* Configure the Analog Filter */ + if (i2c_dev->analog_filter) + stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_ANFOFF); + else + stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_ANFOFF); + + /* Program the Digital Filter */ + stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_DNF_MASK); + stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_DNF(i2c_dev->dnf)); + + stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_PE); +} + +static void stm32f7_i2c_write_tx_data(struct stm32f7_i2c_dev *i2c_dev) +{ + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + void __iomem *base = i2c_dev->base; + + if (f7_msg->count) { + writeb_relaxed(*f7_msg->buf++, base + STM32F7_I2C_TXDR); + f7_msg->count--; + } +} + +static void stm32f7_i2c_read_rx_data(struct stm32f7_i2c_dev *i2c_dev) +{ + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + void __iomem *base = i2c_dev->base; + + if (f7_msg->count) { + *f7_msg->buf++ = readb_relaxed(base + STM32F7_I2C_RXDR); + f7_msg->count--; + } else { + /* Flush RX buffer has no data is expected */ + readb_relaxed(base + STM32F7_I2C_RXDR); + } +} + +static void stm32f7_i2c_reload(struct stm32f7_i2c_dev *i2c_dev) +{ + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + u32 cr2; + + if (i2c_dev->use_dma) + f7_msg->count -= STM32F7_I2C_MAX_LEN; + + cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2); + + cr2 &= ~STM32F7_I2C_CR2_NBYTES_MASK; + if (f7_msg->count > STM32F7_I2C_MAX_LEN) { + cr2 |= STM32F7_I2C_CR2_NBYTES(STM32F7_I2C_MAX_LEN); + } else { + cr2 &= ~STM32F7_I2C_CR2_RELOAD; + cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count); + } + + writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2); +} + +static void stm32f7_i2c_smbus_reload(struct stm32f7_i2c_dev *i2c_dev) +{ + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + u32 cr2; + u8 *val; + + /* + * For I2C_SMBUS_BLOCK_DATA && I2C_SMBUS_BLOCK_PROC_CALL, the first + * data received inform us how many data will follow. + */ + stm32f7_i2c_read_rx_data(i2c_dev); + + /* + * Update NBYTES with the value read to continue the transfer + */ + val = f7_msg->buf - sizeof(u8); + f7_msg->count = *val; + cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2); + cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD); + cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count); + writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2); +} + +static void stm32f7_i2c_release_bus(struct i2c_adapter *i2c_adap) +{ + struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap); + + stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_PE); + + stm32f7_i2c_hw_config(i2c_dev); +} + +static int stm32f7_i2c_wait_free_bus(struct stm32f7_i2c_dev *i2c_dev) +{ + u32 status; + int ret; + + ret = readl_relaxed_poll_timeout(i2c_dev->base + STM32F7_I2C_ISR, + status, + !(status & STM32F7_I2C_ISR_BUSY), + 10, 1000); + if (!ret) + return 0; + + stm32f7_i2c_release_bus(&i2c_dev->adap); + + return -EBUSY; +} + +static void stm32f7_i2c_xfer_msg(struct stm32f7_i2c_dev *i2c_dev, + struct i2c_msg *msg) +{ + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + void __iomem *base = i2c_dev->base; + u32 cr1, cr2; + int ret; + + f7_msg->addr = msg->addr; + f7_msg->buf = msg->buf; + f7_msg->count = msg->len; + f7_msg->result = 0; + f7_msg->stop = (i2c_dev->msg_id >= i2c_dev->msg_num - 1); + + reinit_completion(&i2c_dev->complete); + + cr1 = readl_relaxed(base + STM32F7_I2C_CR1); + cr2 = readl_relaxed(base + STM32F7_I2C_CR2); + + /* Set transfer direction */ + cr2 &= ~STM32F7_I2C_CR2_RD_WRN; + if (msg->flags & I2C_M_RD) + cr2 |= STM32F7_I2C_CR2_RD_WRN; + + /* Set slave address */ + cr2 &= ~(STM32F7_I2C_CR2_HEAD10R | STM32F7_I2C_CR2_ADD10); + if (msg->flags & I2C_M_TEN) { + cr2 &= ~STM32F7_I2C_CR2_SADD10_MASK; + cr2 |= STM32F7_I2C_CR2_SADD10(f7_msg->addr); + cr2 |= STM32F7_I2C_CR2_ADD10; + } else { + cr2 &= ~STM32F7_I2C_CR2_SADD7_MASK; + cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr); + } + + /* Set nb bytes to transfer and reload if needed */ + cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD); + if (f7_msg->count > STM32F7_I2C_MAX_LEN) { + cr2 |= STM32F7_I2C_CR2_NBYTES(STM32F7_I2C_MAX_LEN); + cr2 |= STM32F7_I2C_CR2_RELOAD; + } else { + cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count); + } + + /* Enable NACK, STOP, error and transfer complete interrupts */ + cr1 |= STM32F7_I2C_CR1_ERRIE | STM32F7_I2C_CR1_TCIE | + STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE; + + /* Clear DMA req and TX/RX interrupt */ + cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE | + STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN); + + /* Configure DMA or enable RX/TX interrupt */ + i2c_dev->use_dma = false; + if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN) { + ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma, + msg->flags & I2C_M_RD, + f7_msg->count, f7_msg->buf, + stm32f7_i2c_dma_callback, + i2c_dev); + if (!ret) + i2c_dev->use_dma = true; + else + dev_warn(i2c_dev->dev, "can't use DMA\n"); + } + + if (!i2c_dev->use_dma) { + if (msg->flags & I2C_M_RD) + cr1 |= STM32F7_I2C_CR1_RXIE; + else + cr1 |= STM32F7_I2C_CR1_TXIE; + } else { + if (msg->flags & I2C_M_RD) + cr1 |= STM32F7_I2C_CR1_RXDMAEN; + else + cr1 |= STM32F7_I2C_CR1_TXDMAEN; + } + + /* Configure Start/Repeated Start */ + cr2 |= STM32F7_I2C_CR2_START; + + i2c_dev->master_mode = true; + + /* Write configurations registers */ + writel_relaxed(cr1, base + STM32F7_I2C_CR1); + writel_relaxed(cr2, base + STM32F7_I2C_CR2); +} + +static int stm32f7_i2c_smbus_xfer_msg(struct stm32f7_i2c_dev *i2c_dev, + unsigned short flags, u8 command, + union i2c_smbus_data *data) +{ + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + struct device *dev = i2c_dev->dev; + void __iomem *base = i2c_dev->base; + u32 cr1, cr2; + int i, ret; + + f7_msg->result = 0; + reinit_completion(&i2c_dev->complete); + + cr2 = readl_relaxed(base + STM32F7_I2C_CR2); + cr1 = readl_relaxed(base + STM32F7_I2C_CR1); + + /* Set transfer direction */ + cr2 &= ~STM32F7_I2C_CR2_RD_WRN; + if (f7_msg->read_write) + cr2 |= STM32F7_I2C_CR2_RD_WRN; + + /* Set slave address */ + cr2 &= ~(STM32F7_I2C_CR2_ADD10 | STM32F7_I2C_CR2_SADD7_MASK); + cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr); + + f7_msg->smbus_buf[0] = command; + switch (f7_msg->size) { + case I2C_SMBUS_QUICK: + f7_msg->stop = true; + f7_msg->count = 0; + break; + case I2C_SMBUS_BYTE: + f7_msg->stop = true; + f7_msg->count = 1; + break; + case I2C_SMBUS_BYTE_DATA: + if (f7_msg->read_write) { + f7_msg->stop = false; + f7_msg->count = 1; + cr2 &= ~STM32F7_I2C_CR2_RD_WRN; + } else { + f7_msg->stop = true; + f7_msg->count = 2; + f7_msg->smbus_buf[1] = data->byte; + } + break; + case I2C_SMBUS_WORD_DATA: + if (f7_msg->read_write) { + f7_msg->stop = false; + f7_msg->count = 1; + cr2 &= ~STM32F7_I2C_CR2_RD_WRN; + } else { + f7_msg->stop = true; + f7_msg->count = 3; + f7_msg->smbus_buf[1] = data->word & 0xff; + f7_msg->smbus_buf[2] = data->word >> 8; + } + break; + case I2C_SMBUS_BLOCK_DATA: + if (f7_msg->read_write) { + f7_msg->stop = false; + f7_msg->count = 1; + cr2 &= ~STM32F7_I2C_CR2_RD_WRN; + } else { + f7_msg->stop = true; + if (data->block[0] > I2C_SMBUS_BLOCK_MAX || + !data->block[0]) { + dev_err(dev, "Invalid block write size %d\n", + data->block[0]); + return -EINVAL; + } + f7_msg->count = data->block[0] + 2; + for (i = 1; i < f7_msg->count; i++) + f7_msg->smbus_buf[i] = data->block[i - 1]; + } + break; + case I2C_SMBUS_PROC_CALL: + f7_msg->stop = false; + f7_msg->count = 3; + f7_msg->smbus_buf[1] = data->word & 0xff; + f7_msg->smbus_buf[2] = data->word >> 8; + cr2 &= ~STM32F7_I2C_CR2_RD_WRN; + f7_msg->read_write = I2C_SMBUS_READ; + break; + case I2C_SMBUS_BLOCK_PROC_CALL: + f7_msg->stop = false; + if (data->block[0] > I2C_SMBUS_BLOCK_MAX - 1) { + dev_err(dev, "Invalid block write size %d\n", + data->block[0]); + return -EINVAL; + } + f7_msg->count = data->block[0] + 2; + for (i = 1; i < f7_msg->count; i++) + f7_msg->smbus_buf[i] = data->block[i - 1]; + cr2 &= ~STM32F7_I2C_CR2_RD_WRN; + f7_msg->read_write = I2C_SMBUS_READ; + break; + case I2C_SMBUS_I2C_BLOCK_DATA: + /* Rely on emulated i2c transfer (through master_xfer) */ + return -EOPNOTSUPP; + default: + dev_err(dev, "Unsupported smbus protocol %d\n", f7_msg->size); + return -EOPNOTSUPP; + } + + f7_msg->buf = f7_msg->smbus_buf; + + /* Configure PEC */ + if ((flags & I2C_CLIENT_PEC) && f7_msg->size != I2C_SMBUS_QUICK) { + cr1 |= STM32F7_I2C_CR1_PECEN; + if (!f7_msg->read_write) { + cr2 |= STM32F7_I2C_CR2_PECBYTE; + f7_msg->count++; + } + } else { + cr1 &= ~STM32F7_I2C_CR1_PECEN; + cr2 &= ~STM32F7_I2C_CR2_PECBYTE; + } + + /* Set number of bytes to be transferred */ + cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD); + cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count); + + /* Enable NACK, STOP, error and transfer complete interrupts */ + cr1 |= STM32F7_I2C_CR1_ERRIE | STM32F7_I2C_CR1_TCIE | + STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE; + + /* Clear DMA req and TX/RX interrupt */ + cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE | + STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN); + + /* Configure DMA or enable RX/TX interrupt */ + i2c_dev->use_dma = false; + if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN) { + ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma, + cr2 & STM32F7_I2C_CR2_RD_WRN, + f7_msg->count, f7_msg->buf, + stm32f7_i2c_dma_callback, + i2c_dev); + if (!ret) + i2c_dev->use_dma = true; + else + dev_warn(i2c_dev->dev, "can't use DMA\n"); + } + + if (!i2c_dev->use_dma) { + if (cr2 & STM32F7_I2C_CR2_RD_WRN) + cr1 |= STM32F7_I2C_CR1_RXIE; + else + cr1 |= STM32F7_I2C_CR1_TXIE; + } else { + if (cr2 & STM32F7_I2C_CR2_RD_WRN) + cr1 |= STM32F7_I2C_CR1_RXDMAEN; + else + cr1 |= STM32F7_I2C_CR1_TXDMAEN; + } + + /* Set Start bit */ + cr2 |= STM32F7_I2C_CR2_START; + + i2c_dev->master_mode = true; + + /* Write configurations registers */ + writel_relaxed(cr1, base + STM32F7_I2C_CR1); + writel_relaxed(cr2, base + STM32F7_I2C_CR2); + + return 0; +} + +static void stm32f7_i2c_smbus_rep_start(struct stm32f7_i2c_dev *i2c_dev) +{ + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + void __iomem *base = i2c_dev->base; + u32 cr1, cr2; + int ret; + + cr2 = readl_relaxed(base + STM32F7_I2C_CR2); + cr1 = readl_relaxed(base + STM32F7_I2C_CR1); + + /* Set transfer direction */ + cr2 |= STM32F7_I2C_CR2_RD_WRN; + + switch (f7_msg->size) { + case I2C_SMBUS_BYTE_DATA: + f7_msg->count = 1; + break; + case I2C_SMBUS_WORD_DATA: + case I2C_SMBUS_PROC_CALL: + f7_msg->count = 2; + break; + case I2C_SMBUS_BLOCK_DATA: + case I2C_SMBUS_BLOCK_PROC_CALL: + f7_msg->count = 1; + cr2 |= STM32F7_I2C_CR2_RELOAD; + break; + } + + f7_msg->buf = f7_msg->smbus_buf; + f7_msg->stop = true; + + /* Add one byte for PEC if needed */ + if (cr1 & STM32F7_I2C_CR1_PECEN) { + cr2 |= STM32F7_I2C_CR2_PECBYTE; + f7_msg->count++; + } + + /* Set number of bytes to be transferred */ + cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK); + cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count); + + /* + * Configure RX/TX interrupt: + */ + cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE); + cr1 |= STM32F7_I2C_CR1_RXIE; + + /* + * Configure DMA or enable RX/TX interrupt: + * For I2C_SMBUS_BLOCK_DATA and I2C_SMBUS_BLOCK_PROC_CALL we don't use + * dma as we don't know in advance how many data will be received + */ + cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE | + STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN); + + i2c_dev->use_dma = false; + if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN && + f7_msg->size != I2C_SMBUS_BLOCK_DATA && + f7_msg->size != I2C_SMBUS_BLOCK_PROC_CALL) { + ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma, + cr2 & STM32F7_I2C_CR2_RD_WRN, + f7_msg->count, f7_msg->buf, + stm32f7_i2c_dma_callback, + i2c_dev); + + if (!ret) + i2c_dev->use_dma = true; + else + dev_warn(i2c_dev->dev, "can't use DMA\n"); + } + + if (!i2c_dev->use_dma) + cr1 |= STM32F7_I2C_CR1_RXIE; + else + cr1 |= STM32F7_I2C_CR1_RXDMAEN; + + /* Configure Repeated Start */ + cr2 |= STM32F7_I2C_CR2_START; + + /* Write configurations registers */ + writel_relaxed(cr1, base + STM32F7_I2C_CR1); + writel_relaxed(cr2, base + STM32F7_I2C_CR2); +} + +static int stm32f7_i2c_smbus_check_pec(struct stm32f7_i2c_dev *i2c_dev) +{ + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + u8 count, internal_pec, received_pec; + + internal_pec = readl_relaxed(i2c_dev->base + STM32F7_I2C_PECR); + + switch (f7_msg->size) { + case I2C_SMBUS_BYTE: + case I2C_SMBUS_BYTE_DATA: + received_pec = f7_msg->smbus_buf[1]; + break; + case I2C_SMBUS_WORD_DATA: + case I2C_SMBUS_PROC_CALL: + received_pec = f7_msg->smbus_buf[2]; + break; + case I2C_SMBUS_BLOCK_DATA: + case I2C_SMBUS_BLOCK_PROC_CALL: + count = f7_msg->smbus_buf[0]; + received_pec = f7_msg->smbus_buf[count]; + break; + default: + dev_err(i2c_dev->dev, "Unsupported smbus protocol for PEC\n"); + return -EINVAL; + } + + if (internal_pec != received_pec) { + dev_err(i2c_dev->dev, "Bad PEC 0x%02x vs. 0x%02x\n", + internal_pec, received_pec); + return -EBADMSG; + } + + return 0; +} + +static bool stm32f7_i2c_is_addr_match(struct i2c_client *slave, u32 addcode) +{ + u32 addr; + + if (!slave) + return false; + + if (slave->flags & I2C_CLIENT_TEN) { + /* + * For 10-bit addr, addcode = 11110XY with + * X = Bit 9 of slave address + * Y = Bit 8 of slave address + */ + addr = slave->addr >> 8; + addr |= 0x78; + if (addr == addcode) + return true; + } else { + addr = slave->addr & 0x7f; + if (addr == addcode) + return true; + } + + return false; +} + +static void stm32f7_i2c_slave_start(struct stm32f7_i2c_dev *i2c_dev) +{ + struct i2c_client *slave = i2c_dev->slave_running; + void __iomem *base = i2c_dev->base; + u32 mask; + u8 value = 0; + + if (i2c_dev->slave_dir) { + /* Notify i2c slave that new read transfer is starting */ + i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value); + + /* + * Disable slave TX config in case of I2C combined message + * (I2C Write followed by I2C Read) + */ + mask = STM32F7_I2C_CR2_RELOAD; + stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR2, mask); + mask = STM32F7_I2C_CR1_SBC | STM32F7_I2C_CR1_RXIE | + STM32F7_I2C_CR1_TCIE; + stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask); + + /* Enable TX empty, STOP, NACK interrupts */ + mask = STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE | + STM32F7_I2C_CR1_TXIE; + stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask); + + /* Write 1st data byte */ + writel_relaxed(value, base + STM32F7_I2C_TXDR); + } else { + /* Notify i2c slave that new write transfer is starting */ + i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value); + + /* Set reload mode to be able to ACK/NACK each received byte */ + mask = STM32F7_I2C_CR2_RELOAD; + stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask); + + /* + * Set STOP, NACK, RX empty and transfer complete interrupts.* + * Set Slave Byte Control to be able to ACK/NACK each data + * byte received + */ + mask = STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE | + STM32F7_I2C_CR1_SBC | STM32F7_I2C_CR1_RXIE | + STM32F7_I2C_CR1_TCIE; + stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask); + } +} + +static void stm32f7_i2c_slave_addr(struct stm32f7_i2c_dev *i2c_dev) +{ + void __iomem *base = i2c_dev->base; + u32 isr, addcode, dir, mask; + int i; + + isr = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR); + addcode = STM32F7_I2C_ISR_ADDCODE_GET(isr); + dir = isr & STM32F7_I2C_ISR_DIR; + + for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) { + if (stm32f7_i2c_is_addr_match(i2c_dev->slave[i], addcode)) { + i2c_dev->slave_running = i2c_dev->slave[i]; + i2c_dev->slave_dir = dir; + + /* Start I2C slave processing */ + stm32f7_i2c_slave_start(i2c_dev); + + /* Clear ADDR flag */ + mask = STM32F7_I2C_ICR_ADDRCF; + writel_relaxed(mask, base + STM32F7_I2C_ICR); + break; + } + } +} + +static int stm32f7_i2c_get_slave_id(struct stm32f7_i2c_dev *i2c_dev, + struct i2c_client *slave, int *id) +{ + int i; + + for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) { + if (i2c_dev->slave[i] == slave) { + *id = i; + return 0; + } + } + + dev_err(i2c_dev->dev, "Slave 0x%x not registered\n", slave->addr); + + return -ENODEV; +} + +static int stm32f7_i2c_get_free_slave_id(struct stm32f7_i2c_dev *i2c_dev, + struct i2c_client *slave, int *id) +{ + struct device *dev = i2c_dev->dev; + int i; + + /* + * slave[STM32F7_SLAVE_HOSTNOTIFY] support only SMBus Host address (0x8) + * slave[STM32F7_SLAVE_7_10_BITS_ADDR] supports 7-bit and 10-bit slave address + * slave[STM32F7_SLAVE_7_BITS_ADDR] supports 7-bit slave address only + */ + if (i2c_dev->smbus_mode && (slave->addr == 0x08)) { + if (i2c_dev->slave[STM32F7_SLAVE_HOSTNOTIFY]) + goto fail; + *id = STM32F7_SLAVE_HOSTNOTIFY; + return 0; + } + + for (i = STM32F7_I2C_MAX_SLAVE - 1; i > STM32F7_SLAVE_HOSTNOTIFY; i--) { + if ((i == STM32F7_SLAVE_7_BITS_ADDR) && + (slave->flags & I2C_CLIENT_TEN)) + continue; + if (!i2c_dev->slave[i]) { + *id = i; + return 0; + } + } + +fail: + dev_err(dev, "Slave 0x%x could not be registered\n", slave->addr); + + return -EINVAL; +} + +static bool stm32f7_i2c_is_slave_registered(struct stm32f7_i2c_dev *i2c_dev) +{ + int i; + + for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) { + if (i2c_dev->slave[i]) + return true; + } + + return false; +} + +static bool stm32f7_i2c_is_slave_busy(struct stm32f7_i2c_dev *i2c_dev) +{ + int i, busy; + + busy = 0; + for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) { + if (i2c_dev->slave[i]) + busy++; + } + + return i == busy; +} + +static irqreturn_t stm32f7_i2c_slave_isr_event(struct stm32f7_i2c_dev *i2c_dev) +{ + void __iomem *base = i2c_dev->base; + u32 cr2, status, mask; + u8 val; + int ret; + + status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR); + + /* Slave transmitter mode */ + if (status & STM32F7_I2C_ISR_TXIS) { + i2c_slave_event(i2c_dev->slave_running, + I2C_SLAVE_READ_PROCESSED, + &val); + + /* Write data byte */ + writel_relaxed(val, base + STM32F7_I2C_TXDR); + } + + /* Transfer Complete Reload for Slave receiver mode */ + if (status & STM32F7_I2C_ISR_TCR || status & STM32F7_I2C_ISR_RXNE) { + /* + * Read data byte then set NBYTES to receive next byte or NACK + * the current received byte + */ + val = readb_relaxed(i2c_dev->base + STM32F7_I2C_RXDR); + ret = i2c_slave_event(i2c_dev->slave_running, + I2C_SLAVE_WRITE_RECEIVED, + &val); + if (!ret) { + cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2); + cr2 |= STM32F7_I2C_CR2_NBYTES(1); + writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2); + } else { + mask = STM32F7_I2C_CR2_NACK; + stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask); + } + } + + /* NACK received */ + if (status & STM32F7_I2C_ISR_NACKF) { + dev_dbg(i2c_dev->dev, "<%s>: Receive NACK\n", __func__); + writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR); + } + + /* STOP received */ + if (status & STM32F7_I2C_ISR_STOPF) { + /* Disable interrupts */ + stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_XFER_IRQ_MASK); + + if (i2c_dev->slave_dir) { + /* + * Flush TX buffer in order to not used the byte in + * TXDR for the next transfer + */ + mask = STM32F7_I2C_ISR_TXE; + stm32f7_i2c_set_bits(base + STM32F7_I2C_ISR, mask); + } + + /* Clear STOP flag */ + writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR); + + /* Notify i2c slave that a STOP flag has been detected */ + i2c_slave_event(i2c_dev->slave_running, I2C_SLAVE_STOP, &val); + + i2c_dev->slave_running = NULL; + } + + /* Address match received */ + if (status & STM32F7_I2C_ISR_ADDR) + stm32f7_i2c_slave_addr(i2c_dev); + + return IRQ_HANDLED; +} + +static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data) +{ + struct stm32f7_i2c_dev *i2c_dev = data; + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + struct stm32_i2c_dma *dma = i2c_dev->dma; + void __iomem *base = i2c_dev->base; + u32 status, mask; + int ret = IRQ_HANDLED; + + /* Check if the interrupt if for a slave device */ + if (!i2c_dev->master_mode) { + ret = stm32f7_i2c_slave_isr_event(i2c_dev); + return ret; + } + + status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR); + + /* Tx empty */ + if (status & STM32F7_I2C_ISR_TXIS) + stm32f7_i2c_write_tx_data(i2c_dev); + + /* RX not empty */ + if (status & STM32F7_I2C_ISR_RXNE) + stm32f7_i2c_read_rx_data(i2c_dev); + + /* NACK received */ + if (status & STM32F7_I2C_ISR_NACKF) { + dev_dbg(i2c_dev->dev, "<%s>: Receive NACK (addr %x)\n", + __func__, f7_msg->addr); + writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR); + if (i2c_dev->use_dma) { + stm32f7_i2c_disable_dma_req(i2c_dev); + dmaengine_terminate_async(dma->chan_using); + } + f7_msg->result = -ENXIO; + } + + /* STOP detection flag */ + if (status & STM32F7_I2C_ISR_STOPF) { + /* Disable interrupts */ + if (stm32f7_i2c_is_slave_registered(i2c_dev)) + mask = STM32F7_I2C_XFER_IRQ_MASK; + else + mask = STM32F7_I2C_ALL_IRQ_MASK; + stm32f7_i2c_disable_irq(i2c_dev, mask); + + /* Clear STOP flag */ + writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR); + + if (i2c_dev->use_dma && !f7_msg->result) { + ret = IRQ_WAKE_THREAD; + } else { + i2c_dev->master_mode = false; + complete(&i2c_dev->complete); + } + } + + /* Transfer complete */ + if (status & STM32F7_I2C_ISR_TC) { + if (f7_msg->stop) { + mask = STM32F7_I2C_CR2_STOP; + stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask); + } else if (i2c_dev->use_dma && !f7_msg->result) { + ret = IRQ_WAKE_THREAD; + } else if (f7_msg->smbus) { + stm32f7_i2c_smbus_rep_start(i2c_dev); + } else { + i2c_dev->msg_id++; + i2c_dev->msg++; + stm32f7_i2c_xfer_msg(i2c_dev, i2c_dev->msg); + } + } + + if (status & STM32F7_I2C_ISR_TCR) { + if (f7_msg->smbus) + stm32f7_i2c_smbus_reload(i2c_dev); + else + stm32f7_i2c_reload(i2c_dev); + } + + return ret; +} + +static irqreturn_t stm32f7_i2c_isr_event_thread(int irq, void *data) +{ + struct stm32f7_i2c_dev *i2c_dev = data; + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + struct stm32_i2c_dma *dma = i2c_dev->dma; + u32 status; + int ret; + + /* + * Wait for dma transfer completion before sending next message or + * notity the end of xfer to the client + */ + ret = wait_for_completion_timeout(&i2c_dev->dma->dma_complete, HZ); + if (!ret) { + dev_dbg(i2c_dev->dev, "<%s>: Timed out\n", __func__); + stm32f7_i2c_disable_dma_req(i2c_dev); + dmaengine_terminate_async(dma->chan_using); + f7_msg->result = -ETIMEDOUT; + } + + status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR); + + if (status & STM32F7_I2C_ISR_TC) { + if (f7_msg->smbus) { + stm32f7_i2c_smbus_rep_start(i2c_dev); + } else { + i2c_dev->msg_id++; + i2c_dev->msg++; + stm32f7_i2c_xfer_msg(i2c_dev, i2c_dev->msg); + } + } else { + i2c_dev->master_mode = false; + complete(&i2c_dev->complete); + } + + return IRQ_HANDLED; +} + +static irqreturn_t stm32f7_i2c_isr_error(int irq, void *data) +{ + struct stm32f7_i2c_dev *i2c_dev = data; + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + void __iomem *base = i2c_dev->base; + struct device *dev = i2c_dev->dev; + struct stm32_i2c_dma *dma = i2c_dev->dma; + u32 status; + + status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR); + + /* Bus error */ + if (status & STM32F7_I2C_ISR_BERR) { + dev_err(dev, "<%s>: Bus error accessing addr 0x%x\n", + __func__, f7_msg->addr); + writel_relaxed(STM32F7_I2C_ICR_BERRCF, base + STM32F7_I2C_ICR); + stm32f7_i2c_release_bus(&i2c_dev->adap); + f7_msg->result = -EIO; + } + + /* Arbitration loss */ + if (status & STM32F7_I2C_ISR_ARLO) { + dev_dbg(dev, "<%s>: Arbitration loss accessing addr 0x%x\n", + __func__, f7_msg->addr); + writel_relaxed(STM32F7_I2C_ICR_ARLOCF, base + STM32F7_I2C_ICR); + f7_msg->result = -EAGAIN; + } + + if (status & STM32F7_I2C_ISR_PECERR) { + dev_err(dev, "<%s>: PEC error in reception accessing addr 0x%x\n", + __func__, f7_msg->addr); + writel_relaxed(STM32F7_I2C_ICR_PECCF, base + STM32F7_I2C_ICR); + f7_msg->result = -EINVAL; + } + + if (status & STM32F7_I2C_ISR_ALERT) { + dev_dbg(dev, "<%s>: SMBus alert received\n", __func__); + writel_relaxed(STM32F7_I2C_ICR_ALERTCF, base + STM32F7_I2C_ICR); + i2c_handle_smbus_alert(i2c_dev->alert->ara); + return IRQ_HANDLED; + } + + if (!i2c_dev->slave_running) { + u32 mask; + /* Disable interrupts */ + if (stm32f7_i2c_is_slave_registered(i2c_dev)) + mask = STM32F7_I2C_XFER_IRQ_MASK; + else + mask = STM32F7_I2C_ALL_IRQ_MASK; + stm32f7_i2c_disable_irq(i2c_dev, mask); + } + + /* Disable dma */ + if (i2c_dev->use_dma) { + stm32f7_i2c_disable_dma_req(i2c_dev); + dmaengine_terminate_async(dma->chan_using); + } + + i2c_dev->master_mode = false; + complete(&i2c_dev->complete); + + return IRQ_HANDLED; +} + +static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap, + struct i2c_msg msgs[], int num) +{ + struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap); + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + struct stm32_i2c_dma *dma = i2c_dev->dma; + unsigned long time_left; + int ret; + + i2c_dev->msg = msgs; + i2c_dev->msg_num = num; + i2c_dev->msg_id = 0; + f7_msg->smbus = false; + + ret = pm_runtime_resume_and_get(i2c_dev->dev); + if (ret < 0) + return ret; + + ret = stm32f7_i2c_wait_free_bus(i2c_dev); + if (ret) + goto pm_free; + + stm32f7_i2c_xfer_msg(i2c_dev, msgs); + + time_left = wait_for_completion_timeout(&i2c_dev->complete, + i2c_dev->adap.timeout); + ret = f7_msg->result; + if (ret) { + if (i2c_dev->use_dma) + dmaengine_synchronize(dma->chan_using); + + /* + * It is possible that some unsent data have already been + * written into TXDR. To avoid sending old data in a + * further transfer, flush TXDR in case of any error + */ + writel_relaxed(STM32F7_I2C_ISR_TXE, + i2c_dev->base + STM32F7_I2C_ISR); + goto pm_free; + } + + if (!time_left) { + dev_dbg(i2c_dev->dev, "Access to slave 0x%x timed out\n", + i2c_dev->msg->addr); + if (i2c_dev->use_dma) + dmaengine_terminate_sync(dma->chan_using); + stm32f7_i2c_wait_free_bus(i2c_dev); + ret = -ETIMEDOUT; + } + +pm_free: + pm_runtime_mark_last_busy(i2c_dev->dev); + pm_runtime_put_autosuspend(i2c_dev->dev); + + return (ret < 0) ? ret : num; +} + +static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(adapter); + struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + struct stm32_i2c_dma *dma = i2c_dev->dma; + struct device *dev = i2c_dev->dev; + unsigned long timeout; + int i, ret; + + f7_msg->addr = addr; + f7_msg->size = size; + f7_msg->read_write = read_write; + f7_msg->smbus = true; + + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) + return ret; + + ret = stm32f7_i2c_wait_free_bus(i2c_dev); + if (ret) + goto pm_free; + + ret = stm32f7_i2c_smbus_xfer_msg(i2c_dev, flags, command, data); + if (ret) + goto pm_free; + + timeout = wait_for_completion_timeout(&i2c_dev->complete, + i2c_dev->adap.timeout); + ret = f7_msg->result; + if (ret) { + if (i2c_dev->use_dma) + dmaengine_synchronize(dma->chan_using); + + /* + * It is possible that some unsent data have already been + * written into TXDR. To avoid sending old data in a + * further transfer, flush TXDR in case of any error + */ + writel_relaxed(STM32F7_I2C_ISR_TXE, + i2c_dev->base + STM32F7_I2C_ISR); + goto pm_free; + } + + if (!timeout) { + dev_dbg(dev, "Access to slave 0x%x timed out\n", f7_msg->addr); + if (i2c_dev->use_dma) + dmaengine_terminate_sync(dma->chan_using); + stm32f7_i2c_wait_free_bus(i2c_dev); + ret = -ETIMEDOUT; + goto pm_free; + } + + /* Check PEC */ + if ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK && read_write) { + ret = stm32f7_i2c_smbus_check_pec(i2c_dev); + if (ret) + goto pm_free; + } + + if (read_write && size != I2C_SMBUS_QUICK) { + switch (size) { + case I2C_SMBUS_BYTE: + case I2C_SMBUS_BYTE_DATA: + data->byte = f7_msg->smbus_buf[0]; + break; + case I2C_SMBUS_WORD_DATA: + case I2C_SMBUS_PROC_CALL: + data->word = f7_msg->smbus_buf[0] | + (f7_msg->smbus_buf[1] << 8); + break; + case I2C_SMBUS_BLOCK_DATA: + case I2C_SMBUS_BLOCK_PROC_CALL: + for (i = 0; i <= f7_msg->smbus_buf[0]; i++) + data->block[i] = f7_msg->smbus_buf[i]; + break; + default: + dev_err(dev, "Unsupported smbus transaction\n"); + ret = -EINVAL; + } + } + +pm_free: + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + return ret; +} + +static void stm32f7_i2c_enable_wakeup(struct stm32f7_i2c_dev *i2c_dev, + bool enable) +{ + void __iomem *base = i2c_dev->base; + u32 mask = STM32F7_I2C_CR1_WUPEN; + + if (!i2c_dev->wakeup_src) + return; + + if (enable) { + device_set_wakeup_enable(i2c_dev->dev, true); + stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask); + } else { + device_set_wakeup_enable(i2c_dev->dev, false); + stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask); + } +} + +static int stm32f7_i2c_reg_slave(struct i2c_client *slave) +{ + struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter); + void __iomem *base = i2c_dev->base; + struct device *dev = i2c_dev->dev; + u32 oar1, oar2, mask; + int id, ret; + + if (slave->flags & I2C_CLIENT_PEC) { + dev_err(dev, "SMBus PEC not supported in slave mode\n"); + return -EINVAL; + } + + if (stm32f7_i2c_is_slave_busy(i2c_dev)) { + dev_err(dev, "Too much slave registered\n"); + return -EBUSY; + } + + ret = stm32f7_i2c_get_free_slave_id(i2c_dev, slave, &id); + if (ret) + return ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) + return ret; + + if (!stm32f7_i2c_is_slave_registered(i2c_dev)) + stm32f7_i2c_enable_wakeup(i2c_dev, true); + + switch (id) { + case 0: + /* Slave SMBus Host */ + i2c_dev->slave[id] = slave; + break; + + case 1: + /* Configure Own Address 1 */ + oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1); + oar1 &= ~STM32F7_I2C_OAR1_MASK; + if (slave->flags & I2C_CLIENT_TEN) { + oar1 |= STM32F7_I2C_OAR1_OA1_10(slave->addr); + oar1 |= STM32F7_I2C_OAR1_OA1MODE; + } else { + oar1 |= STM32F7_I2C_OAR1_OA1_7(slave->addr); + } + oar1 |= STM32F7_I2C_OAR1_OA1EN; + i2c_dev->slave[id] = slave; + writel_relaxed(oar1, i2c_dev->base + STM32F7_I2C_OAR1); + break; + + case 2: + /* Configure Own Address 2 */ + oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2); + oar2 &= ~STM32F7_I2C_OAR2_MASK; + if (slave->flags & I2C_CLIENT_TEN) { + ret = -EOPNOTSUPP; + goto pm_free; + } + + oar2 |= STM32F7_I2C_OAR2_OA2_7(slave->addr); + oar2 |= STM32F7_I2C_OAR2_OA2EN; + i2c_dev->slave[id] = slave; + writel_relaxed(oar2, i2c_dev->base + STM32F7_I2C_OAR2); + break; + + default: + dev_err(dev, "I2C slave id not supported\n"); + ret = -ENODEV; + goto pm_free; + } + + /* Enable ACK */ + stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR2, STM32F7_I2C_CR2_NACK); + + /* Enable Address match interrupt, error interrupt and enable I2C */ + mask = STM32F7_I2C_CR1_ADDRIE | STM32F7_I2C_CR1_ERRIE | + STM32F7_I2C_CR1_PE; + stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask); + + ret = 0; +pm_free: + if (!stm32f7_i2c_is_slave_registered(i2c_dev)) + stm32f7_i2c_enable_wakeup(i2c_dev, false); + + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + + return ret; +} + +static int stm32f7_i2c_unreg_slave(struct i2c_client *slave) +{ + struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter); + void __iomem *base = i2c_dev->base; + u32 mask; + int id, ret; + + ret = stm32f7_i2c_get_slave_id(i2c_dev, slave, &id); + if (ret) + return ret; + + WARN_ON(!i2c_dev->slave[id]); + + ret = pm_runtime_resume_and_get(i2c_dev->dev); + if (ret < 0) + return ret; + + if (id == 1) { + mask = STM32F7_I2C_OAR1_OA1EN; + stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR1, mask); + } else if (id == 2) { + mask = STM32F7_I2C_OAR2_OA2EN; + stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR2, mask); + } + + i2c_dev->slave[id] = NULL; + + if (!stm32f7_i2c_is_slave_registered(i2c_dev)) { + stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_ALL_IRQ_MASK); + stm32f7_i2c_enable_wakeup(i2c_dev, false); + } + + pm_runtime_mark_last_busy(i2c_dev->dev); + pm_runtime_put_autosuspend(i2c_dev->dev); + + return 0; +} + +static int stm32f7_i2c_write_fm_plus_bits(struct stm32f7_i2c_dev *i2c_dev, + bool enable) +{ + int ret; + + if (i2c_dev->bus_rate <= I2C_MAX_FAST_MODE_FREQ || + IS_ERR_OR_NULL(i2c_dev->regmap)) + /* Optional */ + return 0; + + if (i2c_dev->fmp_sreg == i2c_dev->fmp_creg) + ret = regmap_update_bits(i2c_dev->regmap, + i2c_dev->fmp_sreg, + i2c_dev->fmp_mask, + enable ? i2c_dev->fmp_mask : 0); + else + ret = regmap_write(i2c_dev->regmap, + enable ? i2c_dev->fmp_sreg : + i2c_dev->fmp_creg, + i2c_dev->fmp_mask); + + return ret; +} + +static int stm32f7_i2c_setup_fm_plus_bits(struct platform_device *pdev, + struct stm32f7_i2c_dev *i2c_dev) +{ + struct device_node *np = pdev->dev.of_node; + int ret; + + i2c_dev->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg-fmp"); + if (IS_ERR(i2c_dev->regmap)) + /* Optional */ + return 0; + + ret = of_property_read_u32_index(np, "st,syscfg-fmp", 1, + &i2c_dev->fmp_sreg); + if (ret) + return ret; + + i2c_dev->fmp_creg = i2c_dev->fmp_sreg + + i2c_dev->setup.fmp_clr_offset; + + return of_property_read_u32_index(np, "st,syscfg-fmp", 2, + &i2c_dev->fmp_mask); +} + +static int stm32f7_i2c_enable_smbus_host(struct stm32f7_i2c_dev *i2c_dev) +{ + struct i2c_adapter *adap = &i2c_dev->adap; + void __iomem *base = i2c_dev->base; + struct i2c_client *client; + + client = i2c_new_slave_host_notify_device(adap); + if (IS_ERR(client)) + return PTR_ERR(client); + + i2c_dev->host_notify_client = client; + + /* Enable SMBus Host address */ + stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, STM32F7_I2C_CR1_SMBHEN); + + return 0; +} + +static void stm32f7_i2c_disable_smbus_host(struct stm32f7_i2c_dev *i2c_dev) +{ + void __iomem *base = i2c_dev->base; + + if (i2c_dev->host_notify_client) { + /* Disable SMBus Host address */ + stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_SMBHEN); + i2c_free_slave_host_notify_device(i2c_dev->host_notify_client); + } +} + +static int stm32f7_i2c_enable_smbus_alert(struct stm32f7_i2c_dev *i2c_dev) +{ + struct stm32f7_i2c_alert *alert; + struct i2c_adapter *adap = &i2c_dev->adap; + struct device *dev = i2c_dev->dev; + void __iomem *base = i2c_dev->base; + + alert = devm_kzalloc(dev, sizeof(*alert), GFP_KERNEL); + if (!alert) + return -ENOMEM; + + alert->ara = i2c_new_smbus_alert_device(adap, &alert->setup); + if (IS_ERR(alert->ara)) + return PTR_ERR(alert->ara); + + i2c_dev->alert = alert; + + /* Enable SMBus Alert */ + stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, STM32F7_I2C_CR1_ALERTEN); + + return 0; +} + +static void stm32f7_i2c_disable_smbus_alert(struct stm32f7_i2c_dev *i2c_dev) +{ + struct stm32f7_i2c_alert *alert = i2c_dev->alert; + void __iomem *base = i2c_dev->base; + + if (alert) { + /* Disable SMBus Alert */ + stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_ALERTEN); + i2c_unregister_device(alert->ara); + } +} + +static u32 stm32f7_i2c_func(struct i2c_adapter *adap) +{ + struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + + u32 func = I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SLAVE | + I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL | + I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_PEC | + I2C_FUNC_SMBUS_I2C_BLOCK; + + if (i2c_dev->smbus_mode) + func |= I2C_FUNC_SMBUS_HOST_NOTIFY; + + return func; +} + +static const struct i2c_algorithm stm32f7_i2c_algo = { + .master_xfer = stm32f7_i2c_xfer, + .smbus_xfer = stm32f7_i2c_smbus_xfer, + .functionality = stm32f7_i2c_func, + .reg_slave = stm32f7_i2c_reg_slave, + .unreg_slave = stm32f7_i2c_unreg_slave, +}; + +static int stm32f7_i2c_probe(struct platform_device *pdev) +{ + struct stm32f7_i2c_dev *i2c_dev; + const struct stm32f7_i2c_setup *setup; + struct resource *res; + struct i2c_adapter *adap; + struct reset_control *rst; + dma_addr_t phy_addr; + int irq_error, irq_event, ret; + + i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); + if (!i2c_dev) + return -ENOMEM; + + i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(i2c_dev->base)) + return PTR_ERR(i2c_dev->base); + phy_addr = (dma_addr_t)res->start; + + irq_event = platform_get_irq(pdev, 0); + if (irq_event < 0) + return irq_event; + + irq_error = platform_get_irq(pdev, 1); + if (irq_error < 0) + return irq_error; + + i2c_dev->wakeup_src = of_property_read_bool(pdev->dev.of_node, + "wakeup-source"); + + i2c_dev->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(i2c_dev->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(i2c_dev->clk), + "Failed to get controller clock\n"); + + ret = clk_prepare_enable(i2c_dev->clk); + if (ret) { + dev_err(&pdev->dev, "Failed to prepare_enable clock\n"); + return ret; + } + + rst = devm_reset_control_get(&pdev->dev, NULL); + if (IS_ERR(rst)) { + ret = dev_err_probe(&pdev->dev, PTR_ERR(rst), + "Error: Missing reset ctrl\n"); + goto clk_free; + } + reset_control_assert(rst); + udelay(2); + reset_control_deassert(rst); + + i2c_dev->dev = &pdev->dev; + + ret = devm_request_threaded_irq(&pdev->dev, irq_event, + stm32f7_i2c_isr_event, + stm32f7_i2c_isr_event_thread, + IRQF_ONESHOT, + pdev->name, i2c_dev); + if (ret) { + dev_err(&pdev->dev, "Failed to request irq event %i\n", + irq_event); + goto clk_free; + } + + ret = devm_request_irq(&pdev->dev, irq_error, stm32f7_i2c_isr_error, 0, + pdev->name, i2c_dev); + if (ret) { + dev_err(&pdev->dev, "Failed to request irq error %i\n", + irq_error); + goto clk_free; + } + + setup = of_device_get_match_data(&pdev->dev); + if (!setup) { + dev_err(&pdev->dev, "Can't get device data\n"); + ret = -ENODEV; + goto clk_free; + } + i2c_dev->setup = *setup; + + ret = stm32f7_i2c_setup_timing(i2c_dev, &i2c_dev->setup); + if (ret) + goto clk_free; + + /* Setup Fast mode plus if necessary */ + if (i2c_dev->bus_rate > I2C_MAX_FAST_MODE_FREQ) { + ret = stm32f7_i2c_setup_fm_plus_bits(pdev, i2c_dev); + if (ret) + goto clk_free; + ret = stm32f7_i2c_write_fm_plus_bits(i2c_dev, true); + if (ret) + goto clk_free; + } + + adap = &i2c_dev->adap; + i2c_set_adapdata(adap, i2c_dev); + snprintf(adap->name, sizeof(adap->name), "STM32F7 I2C(%pa)", + &res->start); + adap->owner = THIS_MODULE; + adap->timeout = 2 * HZ; + adap->retries = 3; + adap->algo = &stm32f7_i2c_algo; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + + init_completion(&i2c_dev->complete); + + /* Init DMA config if supported */ + i2c_dev->dma = stm32_i2c_dma_request(i2c_dev->dev, phy_addr, + STM32F7_I2C_TXDR, + STM32F7_I2C_RXDR); + if (IS_ERR(i2c_dev->dma)) { + ret = PTR_ERR(i2c_dev->dma); + /* DMA support is optional, only report other errors */ + if (ret != -ENODEV) + goto fmp_clear; + dev_dbg(i2c_dev->dev, "No DMA option: fallback using interrupts\n"); + i2c_dev->dma = NULL; + } + + if (i2c_dev->wakeup_src) { + device_set_wakeup_capable(i2c_dev->dev, true); + + ret = dev_pm_set_wake_irq(i2c_dev->dev, irq_event); + if (ret) { + dev_err(i2c_dev->dev, "Failed to set wake up irq\n"); + goto clr_wakeup_capable; + } + } + + platform_set_drvdata(pdev, i2c_dev); + + pm_runtime_set_autosuspend_delay(i2c_dev->dev, + STM32F7_AUTOSUSPEND_DELAY); + pm_runtime_use_autosuspend(i2c_dev->dev); + pm_runtime_set_active(i2c_dev->dev); + pm_runtime_enable(i2c_dev->dev); + + pm_runtime_get_noresume(&pdev->dev); + + stm32f7_i2c_hw_config(i2c_dev); + + i2c_dev->smbus_mode = of_property_read_bool(pdev->dev.of_node, "smbus"); + + ret = i2c_add_adapter(adap); + if (ret) + goto pm_disable; + + if (i2c_dev->smbus_mode) { + ret = stm32f7_i2c_enable_smbus_host(i2c_dev); + if (ret) { + dev_err(i2c_dev->dev, + "failed to enable SMBus Host-Notify protocol (%d)\n", + ret); + goto i2c_adapter_remove; + } + } + + if (of_property_read_bool(pdev->dev.of_node, "smbus-alert")) { + ret = stm32f7_i2c_enable_smbus_alert(i2c_dev); + if (ret) { + dev_err(i2c_dev->dev, + "failed to enable SMBus alert protocol (%d)\n", + ret); + goto i2c_disable_smbus_host; + } + } + + dev_info(i2c_dev->dev, "STM32F7 I2C-%d bus adapter\n", adap->nr); + + pm_runtime_mark_last_busy(i2c_dev->dev); + pm_runtime_put_autosuspend(i2c_dev->dev); + + return 0; + +i2c_disable_smbus_host: + stm32f7_i2c_disable_smbus_host(i2c_dev); + +i2c_adapter_remove: + i2c_del_adapter(adap); + +pm_disable: + pm_runtime_put_noidle(i2c_dev->dev); + pm_runtime_disable(i2c_dev->dev); + pm_runtime_set_suspended(i2c_dev->dev); + pm_runtime_dont_use_autosuspend(i2c_dev->dev); + + if (i2c_dev->wakeup_src) + dev_pm_clear_wake_irq(i2c_dev->dev); + +clr_wakeup_capable: + if (i2c_dev->wakeup_src) + device_set_wakeup_capable(i2c_dev->dev, false); + + if (i2c_dev->dma) { + stm32_i2c_dma_free(i2c_dev->dma); + i2c_dev->dma = NULL; + } + +fmp_clear: + stm32f7_i2c_write_fm_plus_bits(i2c_dev, false); + +clk_free: + clk_disable_unprepare(i2c_dev->clk); + + return ret; +} + +static void stm32f7_i2c_remove(struct platform_device *pdev) +{ + struct stm32f7_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + + stm32f7_i2c_disable_smbus_alert(i2c_dev); + stm32f7_i2c_disable_smbus_host(i2c_dev); + + i2c_del_adapter(&i2c_dev->adap); + pm_runtime_get_sync(i2c_dev->dev); + + if (i2c_dev->wakeup_src) { + dev_pm_clear_wake_irq(i2c_dev->dev); + /* + * enforce that wakeup is disabled and that the device + * is marked as non wakeup capable + */ + device_init_wakeup(i2c_dev->dev, false); + } + + pm_runtime_put_noidle(i2c_dev->dev); + pm_runtime_disable(i2c_dev->dev); + pm_runtime_set_suspended(i2c_dev->dev); + pm_runtime_dont_use_autosuspend(i2c_dev->dev); + + if (i2c_dev->dma) { + stm32_i2c_dma_free(i2c_dev->dma); + i2c_dev->dma = NULL; + } + + stm32f7_i2c_write_fm_plus_bits(i2c_dev, false); + + clk_disable_unprepare(i2c_dev->clk); +} + +static int __maybe_unused stm32f7_i2c_runtime_suspend(struct device *dev) +{ + struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev); + + if (!stm32f7_i2c_is_slave_registered(i2c_dev)) + clk_disable_unprepare(i2c_dev->clk); + + return 0; +} + +static int __maybe_unused stm32f7_i2c_runtime_resume(struct device *dev) +{ + struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int ret; + + if (!stm32f7_i2c_is_slave_registered(i2c_dev)) { + ret = clk_prepare_enable(i2c_dev->clk); + if (ret) { + dev_err(dev, "failed to prepare_enable clock\n"); + return ret; + } + } + + return 0; +} + +static int __maybe_unused stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev) +{ + int ret; + struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs; + + ret = pm_runtime_resume_and_get(i2c_dev->dev); + if (ret < 0) + return ret; + + backup_regs->cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1); + backup_regs->cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2); + backup_regs->oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1); + backup_regs->oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2); + backup_regs->tmgr = readl_relaxed(i2c_dev->base + STM32F7_I2C_TIMINGR); + stm32f7_i2c_write_fm_plus_bits(i2c_dev, false); + + pm_runtime_put_sync(i2c_dev->dev); + + return ret; +} + +static int __maybe_unused stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev) +{ + u32 cr1; + int ret; + struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs; + + ret = pm_runtime_resume_and_get(i2c_dev->dev); + if (ret < 0) + return ret; + + cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1); + if (cr1 & STM32F7_I2C_CR1_PE) + stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_PE); + + writel_relaxed(backup_regs->tmgr, i2c_dev->base + STM32F7_I2C_TIMINGR); + writel_relaxed(backup_regs->cr1 & ~STM32F7_I2C_CR1_PE, + i2c_dev->base + STM32F7_I2C_CR1); + if (backup_regs->cr1 & STM32F7_I2C_CR1_PE) + stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, + STM32F7_I2C_CR1_PE); + writel_relaxed(backup_regs->cr2, i2c_dev->base + STM32F7_I2C_CR2); + writel_relaxed(backup_regs->oar1, i2c_dev->base + STM32F7_I2C_OAR1); + writel_relaxed(backup_regs->oar2, i2c_dev->base + STM32F7_I2C_OAR2); + stm32f7_i2c_write_fm_plus_bits(i2c_dev, true); + + pm_runtime_put_sync(i2c_dev->dev); + + return ret; +} + +static int __maybe_unused stm32f7_i2c_suspend(struct device *dev) +{ + struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int ret; + + i2c_mark_adapter_suspended(&i2c_dev->adap); + + if (!device_may_wakeup(dev) && !device_wakeup_path(dev)) { + ret = stm32f7_i2c_regs_backup(i2c_dev); + if (ret < 0) { + i2c_mark_adapter_resumed(&i2c_dev->adap); + return ret; + } + + pinctrl_pm_select_sleep_state(dev); + pm_runtime_force_suspend(dev); + } + + return 0; +} + +static int __maybe_unused stm32f7_i2c_resume(struct device *dev) +{ + struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int ret; + + if (!device_may_wakeup(dev) && !device_wakeup_path(dev)) { + ret = pm_runtime_force_resume(dev); + if (ret < 0) + return ret; + pinctrl_pm_select_default_state(dev); + + ret = stm32f7_i2c_regs_restore(i2c_dev); + if (ret < 0) + return ret; + } + + i2c_mark_adapter_resumed(&i2c_dev->adap); + + return 0; +} + +static const struct dev_pm_ops stm32f7_i2c_pm_ops = { + SET_RUNTIME_PM_OPS(stm32f7_i2c_runtime_suspend, + stm32f7_i2c_runtime_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(stm32f7_i2c_suspend, stm32f7_i2c_resume) +}; + +static const struct of_device_id stm32f7_i2c_match[] = { + { .compatible = "st,stm32f7-i2c", .data = &stm32f7_setup}, + { .compatible = "st,stm32mp15-i2c", .data = &stm32mp15_setup}, + { .compatible = "st,stm32mp13-i2c", .data = &stm32mp13_setup}, + {}, +}; +MODULE_DEVICE_TABLE(of, stm32f7_i2c_match); + +static struct platform_driver stm32f7_i2c_driver = { + .driver = { + .name = "stm32f7-i2c", + .of_match_table = stm32f7_i2c_match, + .pm = &stm32f7_i2c_pm_ops, + }, + .probe = stm32f7_i2c_probe, + .remove_new = stm32f7_i2c_remove, +}; + +module_platform_driver(stm32f7_i2c_driver); + +MODULE_AUTHOR("M'boumba Cedric Madianga <cedric.madianga@gmail.com>"); +MODULE_DESCRIPTION("STMicroelectronics STM32F7 I2C driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-sun6i-p2wi.c b/drivers/i2c/busses/i2c-sun6i-p2wi.c new file mode 100644 index 000000000..85e035e7a --- /dev/null +++ b/drivers/i2c/busses/i2c-sun6i-p2wi.c @@ -0,0 +1,332 @@ +/* + * P2WI (Push-Pull Two Wire Interface) bus driver. + * + * Author: Boris BREZILLON <boris.brezillon@free-electrons.com> + * + * This file is licensed under the terms of the GNU General Public License + * version 2. This program is licensed "as is" without any warranty of any + * kind, whether express or implied. + * + * The P2WI controller looks like an SMBus controller which only supports byte + * data transfers. But, it differs from standard SMBus protocol on several + * aspects: + * - it supports only one slave device, and thus drop the address field + * - it adds a parity bit every 8bits of data + * - only one read access is required to read a byte (instead of a write + * followed by a read access in standard SMBus protocol) + * - there's no Ack bit after each byte transfer + * + * This means this bus cannot be used to interface with standard SMBus + * devices (the only known device to support this interface is the AXP221 + * PMIC). + * + */ +#include <linux/clk.h> +#include <linux/i2c.h> +#include <linux/io.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reset.h> + + +/* P2WI registers */ +#define P2WI_CTRL 0x0 +#define P2WI_CCR 0x4 +#define P2WI_INTE 0x8 +#define P2WI_INTS 0xc +#define P2WI_DADDR0 0x10 +#define P2WI_DADDR1 0x14 +#define P2WI_DLEN 0x18 +#define P2WI_DATA0 0x1c +#define P2WI_DATA1 0x20 +#define P2WI_LCR 0x24 +#define P2WI_PMCR 0x28 + +/* CTRL fields */ +#define P2WI_CTRL_START_TRANS BIT(7) +#define P2WI_CTRL_ABORT_TRANS BIT(6) +#define P2WI_CTRL_GLOBAL_INT_ENB BIT(1) +#define P2WI_CTRL_SOFT_RST BIT(0) + +/* CLK CTRL fields */ +#define P2WI_CCR_SDA_OUT_DELAY(v) (((v) & 0x7) << 8) +#define P2WI_CCR_MAX_CLK_DIV 0xff +#define P2WI_CCR_CLK_DIV(v) ((v) & P2WI_CCR_MAX_CLK_DIV) + +/* STATUS fields */ +#define P2WI_INTS_TRANS_ERR_ID(v) (((v) >> 8) & 0xff) +#define P2WI_INTS_LOAD_BSY BIT(2) +#define P2WI_INTS_TRANS_ERR BIT(1) +#define P2WI_INTS_TRANS_OVER BIT(0) + +/* DATA LENGTH fields*/ +#define P2WI_DLEN_READ BIT(4) +#define P2WI_DLEN_DATA_LENGTH(v) ((v - 1) & 0x7) + +/* LINE CTRL fields*/ +#define P2WI_LCR_SCL_STATE BIT(5) +#define P2WI_LCR_SDA_STATE BIT(4) +#define P2WI_LCR_SCL_CTL BIT(3) +#define P2WI_LCR_SCL_CTL_EN BIT(2) +#define P2WI_LCR_SDA_CTL BIT(1) +#define P2WI_LCR_SDA_CTL_EN BIT(0) + +/* PMU MODE CTRL fields */ +#define P2WI_PMCR_PMU_INIT_SEND BIT(31) +#define P2WI_PMCR_PMU_INIT_DATA(v) (((v) & 0xff) << 16) +#define P2WI_PMCR_PMU_MODE_REG(v) (((v) & 0xff) << 8) +#define P2WI_PMCR_PMU_DEV_ADDR(v) ((v) & 0xff) + +#define P2WI_MAX_FREQ 6000000 + +struct p2wi { + struct i2c_adapter adapter; + struct completion complete; + unsigned int status; + void __iomem *regs; + struct clk *clk; + struct reset_control *rstc; + int slave_addr; +}; + +static irqreturn_t p2wi_interrupt(int irq, void *dev_id) +{ + struct p2wi *p2wi = dev_id; + unsigned long status; + + status = readl(p2wi->regs + P2WI_INTS); + p2wi->status = status; + + /* Clear interrupts */ + status &= (P2WI_INTS_LOAD_BSY | P2WI_INTS_TRANS_ERR | + P2WI_INTS_TRANS_OVER); + writel(status, p2wi->regs + P2WI_INTS); + + complete(&p2wi->complete); + + return IRQ_HANDLED; +} + +static u32 p2wi_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_SMBUS_BYTE_DATA; +} + +static int p2wi_smbus_xfer(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data *data) +{ + struct p2wi *p2wi = i2c_get_adapdata(adap); + unsigned long dlen = P2WI_DLEN_DATA_LENGTH(1); + + if (p2wi->slave_addr >= 0 && addr != p2wi->slave_addr) { + dev_err(&adap->dev, "invalid P2WI address\n"); + return -EINVAL; + } + + if (!data) + return -EINVAL; + + writel(command, p2wi->regs + P2WI_DADDR0); + + if (read_write == I2C_SMBUS_READ) + dlen |= P2WI_DLEN_READ; + else + writel(data->byte, p2wi->regs + P2WI_DATA0); + + writel(dlen, p2wi->regs + P2WI_DLEN); + + if (readl(p2wi->regs + P2WI_CTRL) & P2WI_CTRL_START_TRANS) { + dev_err(&adap->dev, "P2WI bus busy\n"); + return -EBUSY; + } + + reinit_completion(&p2wi->complete); + + writel(P2WI_INTS_LOAD_BSY | P2WI_INTS_TRANS_ERR | P2WI_INTS_TRANS_OVER, + p2wi->regs + P2WI_INTE); + + writel(P2WI_CTRL_START_TRANS | P2WI_CTRL_GLOBAL_INT_ENB, + p2wi->regs + P2WI_CTRL); + + wait_for_completion(&p2wi->complete); + + if (p2wi->status & P2WI_INTS_LOAD_BSY) { + dev_err(&adap->dev, "P2WI bus busy\n"); + return -EBUSY; + } + + if (p2wi->status & P2WI_INTS_TRANS_ERR) { + dev_err(&adap->dev, "P2WI bus xfer error\n"); + return -ENXIO; + } + + if (read_write == I2C_SMBUS_READ) + data->byte = readl(p2wi->regs + P2WI_DATA0); + + return 0; +} + +static const struct i2c_algorithm p2wi_algo = { + .smbus_xfer = p2wi_smbus_xfer, + .functionality = p2wi_functionality, +}; + +static const struct of_device_id p2wi_of_match_table[] = { + { .compatible = "allwinner,sun6i-a31-p2wi" }, + {} +}; +MODULE_DEVICE_TABLE(of, p2wi_of_match_table); + +static int p2wi_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct device_node *childnp; + unsigned long parent_clk_freq; + u32 clk_freq = I2C_MAX_STANDARD_MODE_FREQ; + struct p2wi *p2wi; + u32 slave_addr; + int clk_div; + int irq; + int ret; + + of_property_read_u32(np, "clock-frequency", &clk_freq); + if (clk_freq > P2WI_MAX_FREQ) { + dev_err(dev, + "required clock-frequency (%u Hz) is too high (max = 6MHz)", + clk_freq); + return -EINVAL; + } + + if (clk_freq == 0) { + dev_err(dev, "clock-frequency is set to 0 in DT\n"); + return -EINVAL; + } + + if (of_get_child_count(np) > 1) { + dev_err(dev, "P2WI only supports one slave device\n"); + return -EINVAL; + } + + p2wi = devm_kzalloc(dev, sizeof(struct p2wi), GFP_KERNEL); + if (!p2wi) + return -ENOMEM; + + p2wi->slave_addr = -1; + + /* + * Authorize a p2wi node without any children to be able to use an + * i2c-dev from userpace. + * In this case the slave_addr is set to -1 and won't be checked when + * launching a P2WI transfer. + */ + childnp = of_get_next_available_child(np, NULL); + if (childnp) { + ret = of_property_read_u32(childnp, "reg", &slave_addr); + if (ret) { + dev_err(dev, "invalid slave address on node %pOF\n", + childnp); + return -EINVAL; + } + + p2wi->slave_addr = slave_addr; + } + + p2wi->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(p2wi->regs)) + return PTR_ERR(p2wi->regs); + + strscpy(p2wi->adapter.name, pdev->name, sizeof(p2wi->adapter.name)); + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + p2wi->clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(p2wi->clk)) { + ret = PTR_ERR(p2wi->clk); + dev_err(dev, "failed to enable clk: %d\n", ret); + return ret; + } + + parent_clk_freq = clk_get_rate(p2wi->clk); + + p2wi->rstc = devm_reset_control_get_exclusive(dev, NULL); + if (IS_ERR(p2wi->rstc)) { + dev_err(dev, "failed to retrieve reset controller: %pe\n", + p2wi->rstc); + return PTR_ERR(p2wi->rstc); + } + + ret = reset_control_deassert(p2wi->rstc); + if (ret) { + dev_err(dev, "failed to deassert reset line: %d\n", ret); + return ret; + } + + init_completion(&p2wi->complete); + p2wi->adapter.dev.parent = dev; + p2wi->adapter.algo = &p2wi_algo; + p2wi->adapter.owner = THIS_MODULE; + p2wi->adapter.dev.of_node = pdev->dev.of_node; + platform_set_drvdata(pdev, p2wi); + i2c_set_adapdata(&p2wi->adapter, p2wi); + + ret = devm_request_irq(dev, irq, p2wi_interrupt, 0, pdev->name, p2wi); + if (ret) { + dev_err(dev, "can't register interrupt handler irq%d: %d\n", + irq, ret); + goto err_reset_assert; + } + + writel(P2WI_CTRL_SOFT_RST, p2wi->regs + P2WI_CTRL); + + clk_div = parent_clk_freq / clk_freq; + if (!clk_div) { + dev_warn(dev, + "clock-frequency is too high, setting it to %lu Hz\n", + parent_clk_freq); + clk_div = 1; + } else if (clk_div > P2WI_CCR_MAX_CLK_DIV) { + dev_warn(dev, + "clock-frequency is too low, setting it to %lu Hz\n", + parent_clk_freq / P2WI_CCR_MAX_CLK_DIV); + clk_div = P2WI_CCR_MAX_CLK_DIV; + } + + writel(P2WI_CCR_SDA_OUT_DELAY(1) | P2WI_CCR_CLK_DIV(clk_div), + p2wi->regs + P2WI_CCR); + + ret = i2c_add_adapter(&p2wi->adapter); + if (!ret) + return 0; + +err_reset_assert: + reset_control_assert(p2wi->rstc); + + return ret; +} + +static void p2wi_remove(struct platform_device *dev) +{ + struct p2wi *p2wi = platform_get_drvdata(dev); + + reset_control_assert(p2wi->rstc); + i2c_del_adapter(&p2wi->adapter); +} + +static struct platform_driver p2wi_driver = { + .probe = p2wi_probe, + .remove_new = p2wi_remove, + .driver = { + .name = "i2c-sunxi-p2wi", + .of_match_table = p2wi_of_match_table, + }, +}; +module_platform_driver(p2wi_driver); + +MODULE_AUTHOR("Boris BREZILLON <boris.brezillon@free-electrons.com>"); +MODULE_DESCRIPTION("Allwinner P2WI driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-synquacer.c b/drivers/i2c/busses/i2c-synquacer.c new file mode 100644 index 000000000..bbea521b0 --- /dev/null +++ b/drivers/i2c/busses/i2c-synquacer.c @@ -0,0 +1,649 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2012 FUJITSU SEMICONDUCTOR LIMITED + */ + +#include <linux/acpi.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +#define WAIT_PCLK(n, rate) \ + ndelay(DIV_ROUND_UP(DIV_ROUND_UP(1000000000, rate), n) + 10) + +/* I2C register address definitions */ +#define SYNQUACER_I2C_REG_BSR (0x00 << 2) // Bus Status +#define SYNQUACER_I2C_REG_BCR (0x01 << 2) // Bus Control +#define SYNQUACER_I2C_REG_CCR (0x02 << 2) // Clock Control +#define SYNQUACER_I2C_REG_ADR (0x03 << 2) // Address +#define SYNQUACER_I2C_REG_DAR (0x04 << 2) // Data +#define SYNQUACER_I2C_REG_CSR (0x05 << 2) // Expansion CS +#define SYNQUACER_I2C_REG_FSR (0x06 << 2) // Bus Clock Freq +#define SYNQUACER_I2C_REG_BC2R (0x07 << 2) // Bus Control 2 + +/* I2C register bit definitions */ +#define SYNQUACER_I2C_BSR_FBT BIT(0) // First Byte Transfer +#define SYNQUACER_I2C_BSR_GCA BIT(1) // General Call Address +#define SYNQUACER_I2C_BSR_AAS BIT(2) // Address as Slave +#define SYNQUACER_I2C_BSR_TRX BIT(3) // Transfer/Receive +#define SYNQUACER_I2C_BSR_LRB BIT(4) // Last Received Bit +#define SYNQUACER_I2C_BSR_AL BIT(5) // Arbitration Lost +#define SYNQUACER_I2C_BSR_RSC BIT(6) // Repeated Start Cond. +#define SYNQUACER_I2C_BSR_BB BIT(7) // Bus Busy + +#define SYNQUACER_I2C_BCR_INT BIT(0) // Interrupt +#define SYNQUACER_I2C_BCR_INTE BIT(1) // Interrupt Enable +#define SYNQUACER_I2C_BCR_GCAA BIT(2) // Gen. Call Access Ack. +#define SYNQUACER_I2C_BCR_ACK BIT(3) // Acknowledge +#define SYNQUACER_I2C_BCR_MSS BIT(4) // Master Slave Select +#define SYNQUACER_I2C_BCR_SCC BIT(5) // Start Condition Cont. +#define SYNQUACER_I2C_BCR_BEIE BIT(6) // Bus Error Int Enable +#define SYNQUACER_I2C_BCR_BER BIT(7) // Bus Error + +#define SYNQUACER_I2C_CCR_CS_MASK (0x1f) // CCR Clock Period Sel. +#define SYNQUACER_I2C_CCR_EN BIT(5) // Enable +#define SYNQUACER_I2C_CCR_FM BIT(6) // Speed Mode Select + +#define SYNQUACER_I2C_CSR_CS_MASK (0x3f) // CSR Clock Period Sel. + +#define SYNQUACER_I2C_BC2R_SCLL BIT(0) // SCL Low Drive +#define SYNQUACER_I2C_BC2R_SDAL BIT(1) // SDA Low Drive +#define SYNQUACER_I2C_BC2R_SCLS BIT(4) // SCL Status +#define SYNQUACER_I2C_BC2R_SDAS BIT(5) // SDA Status + +/* PCLK frequency */ +#define SYNQUACER_I2C_BUS_CLK_FR(rate) (((rate) / 20000000) + 1) + +/* STANDARD MODE frequency */ +#define SYNQUACER_I2C_CLK_MASTER_STD(rate) \ + DIV_ROUND_UP(DIV_ROUND_UP((rate), I2C_MAX_STANDARD_MODE_FREQ) - 2, 2) +/* FAST MODE frequency */ +#define SYNQUACER_I2C_CLK_MASTER_FAST(rate) \ + DIV_ROUND_UP((DIV_ROUND_UP((rate), I2C_MAX_FAST_MODE_FREQ) - 2) * 2, 3) + +/* (clkrate <= 18000000) */ +/* calculate the value of CS bits in CCR register on standard mode */ +#define SYNQUACER_I2C_CCR_CS_STD_MAX_18M(rate) \ + ((SYNQUACER_I2C_CLK_MASTER_STD(rate) - 65) \ + & SYNQUACER_I2C_CCR_CS_MASK) + +/* calculate the value of CS bits in CSR register on standard mode */ +#define SYNQUACER_I2C_CSR_CS_STD_MAX_18M(rate) 0x00 + +/* calculate the value of CS bits in CCR register on fast mode */ +#define SYNQUACER_I2C_CCR_CS_FAST_MAX_18M(rate) \ + ((SYNQUACER_I2C_CLK_MASTER_FAST(rate) - 1) \ + & SYNQUACER_I2C_CCR_CS_MASK) + +/* calculate the value of CS bits in CSR register on fast mode */ +#define SYNQUACER_I2C_CSR_CS_FAST_MAX_18M(rate) 0x00 + +/* (clkrate > 18000000) */ +/* calculate the value of CS bits in CCR register on standard mode */ +#define SYNQUACER_I2C_CCR_CS_STD_MIN_18M(rate) \ + ((SYNQUACER_I2C_CLK_MASTER_STD(rate) - 1) \ + & SYNQUACER_I2C_CCR_CS_MASK) + +/* calculate the value of CS bits in CSR register on standard mode */ +#define SYNQUACER_I2C_CSR_CS_STD_MIN_18M(rate) \ + (((SYNQUACER_I2C_CLK_MASTER_STD(rate) - 1) >> 5) \ + & SYNQUACER_I2C_CSR_CS_MASK) + +/* calculate the value of CS bits in CCR register on fast mode */ +#define SYNQUACER_I2C_CCR_CS_FAST_MIN_18M(rate) \ + ((SYNQUACER_I2C_CLK_MASTER_FAST(rate) - 1) \ + & SYNQUACER_I2C_CCR_CS_MASK) + +/* calculate the value of CS bits in CSR register on fast mode */ +#define SYNQUACER_I2C_CSR_CS_FAST_MIN_18M(rate) \ + (((SYNQUACER_I2C_CLK_MASTER_FAST(rate) - 1) >> 5) \ + & SYNQUACER_I2C_CSR_CS_MASK) + +/* min I2C clock frequency 14M */ +#define SYNQUACER_I2C_MIN_CLK_RATE (14 * 1000000) +/* max I2C clock frequency 200M */ +#define SYNQUACER_I2C_MAX_CLK_RATE (200 * 1000000) +/* I2C clock frequency 18M */ +#define SYNQUACER_I2C_CLK_RATE_18M (18 * 1000000) + +#define SYNQUACER_I2C_SPEED_FM 400 // Fast Mode +#define SYNQUACER_I2C_SPEED_SM 100 // Standard Mode + +enum i2c_state { + STATE_IDLE, + STATE_START, + STATE_READ, + STATE_WRITE +}; + +struct synquacer_i2c { + struct completion completion; + + struct i2c_msg *msg; + u32 msg_num; + u32 msg_idx; + u32 msg_ptr; + + int irq; + struct device *dev; + void __iomem *base; + struct clk *pclk; + u32 pclkrate; + u32 speed_khz; + u32 timeout_ms; + enum i2c_state state; + struct i2c_adapter adapter; +}; + +static inline int is_lastmsg(struct synquacer_i2c *i2c) +{ + return i2c->msg_idx >= (i2c->msg_num - 1); +} + +static inline int is_msglast(struct synquacer_i2c *i2c) +{ + return i2c->msg_ptr == (i2c->msg->len - 1); +} + +static inline int is_msgend(struct synquacer_i2c *i2c) +{ + return i2c->msg_ptr >= i2c->msg->len; +} + +static inline unsigned long calc_timeout_ms(struct synquacer_i2c *i2c, + struct i2c_msg *msgs, + int num) +{ + unsigned long bit_count = 0; + int i; + + for (i = 0; i < num; i++, msgs++) + bit_count += msgs->len; + + return DIV_ROUND_UP((bit_count * 9 + num * 10) * 3, 200) + 10; +} + +static void synquacer_i2c_stop(struct synquacer_i2c *i2c, int ret) +{ + /* + * clear IRQ (INT=0, BER=0) + * set Stop Condition (MSS=0) + * Interrupt Disable + */ + writeb(0, i2c->base + SYNQUACER_I2C_REG_BCR); + + i2c->state = STATE_IDLE; + + i2c->msg_ptr = 0; + i2c->msg = NULL; + i2c->msg_idx++; + i2c->msg_num = 0; + if (ret) + i2c->msg_idx = ret; + + complete(&i2c->completion); +} + +static void synquacer_i2c_hw_init(struct synquacer_i2c *i2c) +{ + unsigned char ccr_cs, csr_cs; + u32 rt = i2c->pclkrate; + + /* Set own Address */ + writeb(0, i2c->base + SYNQUACER_I2C_REG_ADR); + + /* Set PCLK frequency */ + writeb(SYNQUACER_I2C_BUS_CLK_FR(i2c->pclkrate), + i2c->base + SYNQUACER_I2C_REG_FSR); + + switch (i2c->speed_khz) { + case SYNQUACER_I2C_SPEED_FM: + if (i2c->pclkrate <= SYNQUACER_I2C_CLK_RATE_18M) { + ccr_cs = SYNQUACER_I2C_CCR_CS_FAST_MAX_18M(rt); + csr_cs = SYNQUACER_I2C_CSR_CS_FAST_MAX_18M(rt); + } else { + ccr_cs = SYNQUACER_I2C_CCR_CS_FAST_MIN_18M(rt); + csr_cs = SYNQUACER_I2C_CSR_CS_FAST_MIN_18M(rt); + } + + /* Set Clock and enable, Set fast mode */ + writeb(ccr_cs | SYNQUACER_I2C_CCR_FM | + SYNQUACER_I2C_CCR_EN, + i2c->base + SYNQUACER_I2C_REG_CCR); + writeb(csr_cs, i2c->base + SYNQUACER_I2C_REG_CSR); + break; + case SYNQUACER_I2C_SPEED_SM: + if (i2c->pclkrate <= SYNQUACER_I2C_CLK_RATE_18M) { + ccr_cs = SYNQUACER_I2C_CCR_CS_STD_MAX_18M(rt); + csr_cs = SYNQUACER_I2C_CSR_CS_STD_MAX_18M(rt); + } else { + ccr_cs = SYNQUACER_I2C_CCR_CS_STD_MIN_18M(rt); + csr_cs = SYNQUACER_I2C_CSR_CS_STD_MIN_18M(rt); + } + + /* Set Clock and enable, Set standard mode */ + writeb(ccr_cs | SYNQUACER_I2C_CCR_EN, + i2c->base + SYNQUACER_I2C_REG_CCR); + writeb(csr_cs, i2c->base + SYNQUACER_I2C_REG_CSR); + break; + default: + WARN_ON(1); + } + + /* clear IRQ (INT=0, BER=0), Interrupt Disable */ + writeb(0, i2c->base + SYNQUACER_I2C_REG_BCR); + writeb(0, i2c->base + SYNQUACER_I2C_REG_BC2R); +} + +static void synquacer_i2c_hw_reset(struct synquacer_i2c *i2c) +{ + /* Disable clock */ + writeb(0, i2c->base + SYNQUACER_I2C_REG_CCR); + writeb(0, i2c->base + SYNQUACER_I2C_REG_CSR); + + WAIT_PCLK(100, i2c->pclkrate); +} + +static int synquacer_i2c_master_start(struct synquacer_i2c *i2c, + struct i2c_msg *pmsg) +{ + unsigned char bsr, bcr; + + writeb(i2c_8bit_addr_from_msg(pmsg), i2c->base + SYNQUACER_I2C_REG_DAR); + + dev_dbg(i2c->dev, "slave:0x%02x\n", pmsg->addr); + + /* Generate Start Condition */ + bsr = readb(i2c->base + SYNQUACER_I2C_REG_BSR); + bcr = readb(i2c->base + SYNQUACER_I2C_REG_BCR); + dev_dbg(i2c->dev, "bsr:0x%02x, bcr:0x%02x\n", bsr, bcr); + + if ((bsr & SYNQUACER_I2C_BSR_BB) && + !(bcr & SYNQUACER_I2C_BCR_MSS)) { + dev_dbg(i2c->dev, "bus is busy"); + return -EBUSY; + } + + if (bsr & SYNQUACER_I2C_BSR_BB) { /* Bus is busy */ + dev_dbg(i2c->dev, "Continuous Start"); + writeb(bcr | SYNQUACER_I2C_BCR_SCC, + i2c->base + SYNQUACER_I2C_REG_BCR); + } else { + if (bcr & SYNQUACER_I2C_BCR_MSS) { + dev_dbg(i2c->dev, "not in master mode"); + return -EAGAIN; + } + dev_dbg(i2c->dev, "Start Condition"); + /* Start Condition + Enable Interrupts */ + writeb(bcr | SYNQUACER_I2C_BCR_MSS | + SYNQUACER_I2C_BCR_INTE | SYNQUACER_I2C_BCR_BEIE, + i2c->base + SYNQUACER_I2C_REG_BCR); + } + + WAIT_PCLK(10, i2c->pclkrate); + + /* get BSR & BCR registers */ + bsr = readb(i2c->base + SYNQUACER_I2C_REG_BSR); + bcr = readb(i2c->base + SYNQUACER_I2C_REG_BCR); + dev_dbg(i2c->dev, "bsr:0x%02x, bcr:0x%02x\n", bsr, bcr); + + if ((bsr & SYNQUACER_I2C_BSR_AL) || + !(bcr & SYNQUACER_I2C_BCR_MSS)) { + dev_dbg(i2c->dev, "arbitration lost\n"); + return -EAGAIN; + } + + return 0; +} + +static int synquacer_i2c_doxfer(struct synquacer_i2c *i2c, + struct i2c_msg *msgs, int num) +{ + unsigned char bsr; + unsigned long timeout; + int ret; + + synquacer_i2c_hw_init(i2c); + bsr = readb(i2c->base + SYNQUACER_I2C_REG_BSR); + if (bsr & SYNQUACER_I2C_BSR_BB) { + dev_err(i2c->dev, "cannot get bus (bus busy)\n"); + return -EBUSY; + } + + reinit_completion(&i2c->completion); + + i2c->msg = msgs; + i2c->msg_num = num; + i2c->msg_ptr = 0; + i2c->msg_idx = 0; + i2c->state = STATE_START; + + ret = synquacer_i2c_master_start(i2c, i2c->msg); + if (ret < 0) { + dev_dbg(i2c->dev, "Address failed: (%d)\n", ret); + return ret; + } + + timeout = wait_for_completion_timeout(&i2c->completion, + msecs_to_jiffies(i2c->timeout_ms)); + if (timeout == 0) { + dev_dbg(i2c->dev, "timeout\n"); + return -EAGAIN; + } + + ret = i2c->msg_idx; + if (ret != num) { + dev_dbg(i2c->dev, "incomplete xfer (%d)\n", ret); + return -EAGAIN; + } + + /* wait 2 clock periods to ensure the stop has been through the bus */ + udelay(DIV_ROUND_UP(2 * 1000, i2c->speed_khz)); + + return ret; +} + +static irqreturn_t synquacer_i2c_isr(int irq, void *dev_id) +{ + struct synquacer_i2c *i2c = dev_id; + + unsigned char byte; + unsigned char bsr, bcr; + int ret; + + bcr = readb(i2c->base + SYNQUACER_I2C_REG_BCR); + bsr = readb(i2c->base + SYNQUACER_I2C_REG_BSR); + dev_dbg(i2c->dev, "bsr:0x%02x, bcr:0x%02x\n", bsr, bcr); + + if (bcr & SYNQUACER_I2C_BCR_BER) { + dev_err(i2c->dev, "bus error\n"); + synquacer_i2c_stop(i2c, -EAGAIN); + goto out; + } + if ((bsr & SYNQUACER_I2C_BSR_AL) || + !(bcr & SYNQUACER_I2C_BCR_MSS)) { + dev_dbg(i2c->dev, "arbitration lost\n"); + synquacer_i2c_stop(i2c, -EAGAIN); + goto out; + } + + switch (i2c->state) { + case STATE_START: + if (bsr & SYNQUACER_I2C_BSR_LRB) { + dev_dbg(i2c->dev, "ack was not received\n"); + synquacer_i2c_stop(i2c, -EAGAIN); + goto out; + } + + if (i2c->msg->flags & I2C_M_RD) + i2c->state = STATE_READ; + else + i2c->state = STATE_WRITE; + + if (is_lastmsg(i2c) && i2c->msg->len == 0) { + synquacer_i2c_stop(i2c, 0); + goto out; + } + + if (i2c->state == STATE_READ) + goto prepare_read; + fallthrough; + + case STATE_WRITE: + if (bsr & SYNQUACER_I2C_BSR_LRB) { + dev_dbg(i2c->dev, "WRITE: No Ack\n"); + synquacer_i2c_stop(i2c, -EAGAIN); + goto out; + } + + if (!is_msgend(i2c)) { + writeb(i2c->msg->buf[i2c->msg_ptr++], + i2c->base + SYNQUACER_I2C_REG_DAR); + + /* clear IRQ, and continue */ + writeb(SYNQUACER_I2C_BCR_BEIE | + SYNQUACER_I2C_BCR_MSS | + SYNQUACER_I2C_BCR_INTE, + i2c->base + SYNQUACER_I2C_REG_BCR); + break; + } + if (is_lastmsg(i2c)) { + synquacer_i2c_stop(i2c, 0); + break; + } + dev_dbg(i2c->dev, "WRITE: Next Message\n"); + + i2c->msg_ptr = 0; + i2c->msg_idx++; + i2c->msg++; + + /* send the new start */ + ret = synquacer_i2c_master_start(i2c, i2c->msg); + if (ret < 0) { + dev_dbg(i2c->dev, "restart error (%d)\n", ret); + synquacer_i2c_stop(i2c, -EAGAIN); + break; + } + i2c->state = STATE_START; + break; + + case STATE_READ: + byte = readb(i2c->base + SYNQUACER_I2C_REG_DAR); + if (!(bsr & SYNQUACER_I2C_BSR_FBT)) /* data */ + i2c->msg->buf[i2c->msg_ptr++] = byte; + else /* address */ + dev_dbg(i2c->dev, "address:0x%02x. ignore it.\n", byte); + +prepare_read: + if (is_msglast(i2c)) { + writeb(SYNQUACER_I2C_BCR_MSS | + SYNQUACER_I2C_BCR_BEIE | + SYNQUACER_I2C_BCR_INTE, + i2c->base + SYNQUACER_I2C_REG_BCR); + break; + } + if (!is_msgend(i2c)) { + writeb(SYNQUACER_I2C_BCR_MSS | + SYNQUACER_I2C_BCR_BEIE | + SYNQUACER_I2C_BCR_INTE | + SYNQUACER_I2C_BCR_ACK, + i2c->base + SYNQUACER_I2C_REG_BCR); + break; + } + if (is_lastmsg(i2c)) { + /* last message, send stop and complete */ + dev_dbg(i2c->dev, "READ: Send Stop\n"); + synquacer_i2c_stop(i2c, 0); + break; + } + dev_dbg(i2c->dev, "READ: Next Transfer\n"); + + i2c->msg_ptr = 0; + i2c->msg_idx++; + i2c->msg++; + + ret = synquacer_i2c_master_start(i2c, i2c->msg); + if (ret < 0) { + dev_dbg(i2c->dev, "restart error (%d)\n", ret); + synquacer_i2c_stop(i2c, -EAGAIN); + } else { + i2c->state = STATE_START; + } + break; + default: + dev_err(i2c->dev, "called in err STATE (%d)\n", i2c->state); + break; + } + +out: + WAIT_PCLK(10, i2c->pclkrate); + return IRQ_HANDLED; +} + +static int synquacer_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct synquacer_i2c *i2c; + int retry; + int ret; + + i2c = i2c_get_adapdata(adap); + i2c->timeout_ms = calc_timeout_ms(i2c, msgs, num); + + dev_dbg(i2c->dev, "calculated timeout %d ms\n", i2c->timeout_ms); + + for (retry = 0; retry <= adap->retries; retry++) { + ret = synquacer_i2c_doxfer(i2c, msgs, num); + if (ret != -EAGAIN) + return ret; + + dev_dbg(i2c->dev, "Retrying transmission (%d)\n", retry); + + synquacer_i2c_hw_reset(i2c); + } + return -EIO; +} + +static u32 synquacer_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm synquacer_i2c_algo = { + .master_xfer = synquacer_i2c_xfer, + .functionality = synquacer_i2c_functionality, +}; + +static const struct i2c_adapter synquacer_i2c_ops = { + .owner = THIS_MODULE, + .name = "synquacer_i2c-adapter", + .algo = &synquacer_i2c_algo, + .retries = 5, +}; + +static int synquacer_i2c_probe(struct platform_device *pdev) +{ + struct synquacer_i2c *i2c; + u32 bus_speed; + int ret; + + i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + bus_speed = i2c_acpi_find_bus_speed(&pdev->dev); + if (!bus_speed) + device_property_read_u32(&pdev->dev, "clock-frequency", + &bus_speed); + + device_property_read_u32(&pdev->dev, "socionext,pclk-rate", + &i2c->pclkrate); + + i2c->pclk = devm_clk_get(&pdev->dev, "pclk"); + if (PTR_ERR(i2c->pclk) == -EPROBE_DEFER) + return -EPROBE_DEFER; + if (!IS_ERR_OR_NULL(i2c->pclk)) { + dev_dbg(&pdev->dev, "clock source %p\n", i2c->pclk); + + ret = clk_prepare_enable(i2c->pclk); + if (ret) + return dev_err_probe(&pdev->dev, ret, "failed to enable clock\n"); + i2c->pclkrate = clk_get_rate(i2c->pclk); + } + + if (i2c->pclkrate < SYNQUACER_I2C_MIN_CLK_RATE || + i2c->pclkrate > SYNQUACER_I2C_MAX_CLK_RATE) + return dev_err_probe(&pdev->dev, -EINVAL, + "PCLK missing or out of range (%d)\n", + i2c->pclkrate); + + i2c->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c->base)) + return PTR_ERR(i2c->base); + + i2c->irq = platform_get_irq(pdev, 0); + if (i2c->irq < 0) + return i2c->irq; + + ret = devm_request_irq(&pdev->dev, i2c->irq, synquacer_i2c_isr, + 0, dev_name(&pdev->dev), i2c); + if (ret < 0) + return dev_err_probe(&pdev->dev, ret, "cannot claim IRQ %d\n", i2c->irq); + + i2c->state = STATE_IDLE; + i2c->dev = &pdev->dev; + i2c->adapter = synquacer_i2c_ops; + i2c_set_adapdata(&i2c->adapter, i2c); + i2c->adapter.dev.parent = &pdev->dev; + i2c->adapter.dev.of_node = pdev->dev.of_node; + ACPI_COMPANION_SET(&i2c->adapter.dev, ACPI_COMPANION(&pdev->dev)); + i2c->adapter.nr = pdev->id; + init_completion(&i2c->completion); + + if (bus_speed < I2C_MAX_FAST_MODE_FREQ) + i2c->speed_khz = SYNQUACER_I2C_SPEED_SM; + else + i2c->speed_khz = SYNQUACER_I2C_SPEED_FM; + + synquacer_i2c_hw_init(i2c); + + ret = i2c_add_numbered_adapter(&i2c->adapter); + if (ret) + return dev_err_probe(&pdev->dev, ret, "failed to add bus to i2c core\n"); + + platform_set_drvdata(pdev, i2c); + + dev_info(&pdev->dev, "%s: synquacer_i2c adapter\n", + dev_name(&i2c->adapter.dev)); + + return 0; +} + +static void synquacer_i2c_remove(struct platform_device *pdev) +{ + struct synquacer_i2c *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adapter); + if (!IS_ERR(i2c->pclk)) + clk_disable_unprepare(i2c->pclk); +}; + +static const struct of_device_id synquacer_i2c_dt_ids[] __maybe_unused = { + { .compatible = "socionext,synquacer-i2c" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, synquacer_i2c_dt_ids); + +#ifdef CONFIG_ACPI +static const struct acpi_device_id synquacer_i2c_acpi_ids[] = { + { "SCX0003" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(acpi, synquacer_i2c_acpi_ids); +#endif + +static struct platform_driver synquacer_i2c_driver = { + .probe = synquacer_i2c_probe, + .remove_new = synquacer_i2c_remove, + .driver = { + .name = "synquacer_i2c", + .of_match_table = of_match_ptr(synquacer_i2c_dt_ids), + .acpi_match_table = ACPI_PTR(synquacer_i2c_acpi_ids), + }, +}; +module_platform_driver(synquacer_i2c_driver); + +MODULE_AUTHOR("Fujitsu Semiconductor Ltd"); +MODULE_DESCRIPTION("Socionext SynQuacer I2C Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-taos-evm.c b/drivers/i2c/busses/i2c-taos-evm.c new file mode 100644 index 000000000..b0f012079 --- /dev/null +++ b/drivers/i2c/busses/i2c-taos-evm.c @@ -0,0 +1,311 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for the TAOS evaluation modules + * These devices include an I2C master which can be controlled over the + * serial port. + * + * Copyright (C) 2007 Jean Delvare <jdelvare@suse.de> + */ + +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/input.h> +#include <linux/serio.h> +#include <linux/init.h> +#include <linux/i2c.h> + +#define TAOS_BUFFER_SIZE 63 + +#define TAOS_STATE_INIT 0 +#define TAOS_STATE_IDLE 1 +#define TAOS_STATE_EOFF 2 +#define TAOS_STATE_RECV 3 + +#define TAOS_CMD_RESET 0x12 +#define TAOS_CMD_ECHO_ON '+' +#define TAOS_CMD_ECHO_OFF '-' + +static DECLARE_WAIT_QUEUE_HEAD(wq); + +struct taos_data { + struct i2c_adapter adapter; + struct i2c_client *client; + int state; + u8 addr; /* last used address */ + unsigned char buffer[TAOS_BUFFER_SIZE]; + unsigned int pos; /* position inside the buffer */ +}; + +/* TAOS TSL2550 EVM */ +static const struct i2c_board_info tsl2550_info = { + I2C_BOARD_INFO("tsl2550", 0x39), +}; + +/* Instantiate i2c devices based on the adapter name */ +static struct i2c_client *taos_instantiate_device(struct i2c_adapter *adapter) +{ + if (!strncmp(adapter->name, "TAOS TSL2550 EVM", 16)) { + dev_info(&adapter->dev, "Instantiating device %s at 0x%02x\n", + tsl2550_info.type, tsl2550_info.addr); + return i2c_new_client_device(adapter, &tsl2550_info); + } + + return ERR_PTR(-ENODEV); +} + +static int taos_smbus_xfer(struct i2c_adapter *adapter, u16 addr, + unsigned short flags, char read_write, u8 command, + int size, union i2c_smbus_data *data) +{ + struct serio *serio = adapter->algo_data; + struct taos_data *taos = serio_get_drvdata(serio); + char *p; + + /* Encode our transaction. "@" is for the device address, "$" for the + SMBus command and "#" for the data. */ + p = taos->buffer; + + /* The device remembers the last used address, no need to send it + again if it's the same */ + if (addr != taos->addr) + p += sprintf(p, "@%02X", addr); + + switch (size) { + case I2C_SMBUS_BYTE: + if (read_write == I2C_SMBUS_WRITE) + sprintf(p, "$#%02X", command); + else + sprintf(p, "$"); + break; + case I2C_SMBUS_BYTE_DATA: + if (read_write == I2C_SMBUS_WRITE) + sprintf(p, "$%02X#%02X", command, data->byte); + else + sprintf(p, "$%02X", command); + break; + default: + dev_warn(&adapter->dev, "Unsupported transaction %d\n", size); + return -EOPNOTSUPP; + } + + /* Send the transaction to the TAOS EVM */ + dev_dbg(&adapter->dev, "Command buffer: %s\n", taos->buffer); + for (p = taos->buffer; *p; p++) + serio_write(serio, *p); + + taos->addr = addr; + + /* Start the transaction and read the answer */ + taos->pos = 0; + taos->state = TAOS_STATE_RECV; + serio_write(serio, read_write == I2C_SMBUS_WRITE ? '>' : '<'); + wait_event_interruptible_timeout(wq, taos->state == TAOS_STATE_IDLE, + msecs_to_jiffies(150)); + if (taos->state != TAOS_STATE_IDLE + || taos->pos != 5) { + dev_err(&adapter->dev, "Transaction timeout (pos=%d)\n", + taos->pos); + return -EIO; + } + dev_dbg(&adapter->dev, "Answer buffer: %s\n", taos->buffer); + + /* Interpret the returned string */ + p = taos->buffer + 1; + p[3] = '\0'; + if (!strcmp(p, "NAK")) + return -ENODEV; + + if (read_write == I2C_SMBUS_WRITE) { + if (!strcmp(p, "ACK")) + return 0; + } else { + if (p[0] == 'x') { + /* + * Voluntarily dropping error code of kstrtou8 since all + * error code that it could return are invalid according + * to Documentation/i2c/fault-codes.rst. + */ + if (kstrtou8(p + 1, 16, &data->byte)) + return -EPROTO; + return 0; + } + } + + return -EIO; +} + +static u32 taos_smbus_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA; +} + +static const struct i2c_algorithm taos_algorithm = { + .smbus_xfer = taos_smbus_xfer, + .functionality = taos_smbus_func, +}; + +static irqreturn_t taos_interrupt(struct serio *serio, unsigned char data, + unsigned int flags) +{ + struct taos_data *taos = serio_get_drvdata(serio); + + switch (taos->state) { + case TAOS_STATE_INIT: + taos->buffer[taos->pos++] = data; + if (data == ':' + || taos->pos == TAOS_BUFFER_SIZE - 1) { + taos->buffer[taos->pos] = '\0'; + taos->state = TAOS_STATE_IDLE; + wake_up_interruptible(&wq); + } + break; + case TAOS_STATE_EOFF: + taos->state = TAOS_STATE_IDLE; + wake_up_interruptible(&wq); + break; + case TAOS_STATE_RECV: + taos->buffer[taos->pos++] = data; + if (data == ']') { + taos->buffer[taos->pos] = '\0'; + taos->state = TAOS_STATE_IDLE; + wake_up_interruptible(&wq); + } + break; + } + + return IRQ_HANDLED; +} + +/* Extract the adapter name from the buffer received after reset. + The buffer is modified and a pointer inside the buffer is returned. */ +static char *taos_adapter_name(char *buffer) +{ + char *start, *end; + + start = strstr(buffer, "TAOS "); + if (!start) + return NULL; + + end = strchr(start, '\r'); + if (!end) + return NULL; + *end = '\0'; + + return start; +} + +static int taos_connect(struct serio *serio, struct serio_driver *drv) +{ + struct taos_data *taos; + struct i2c_adapter *adapter; + char *name; + int err; + + taos = kzalloc(sizeof(struct taos_data), GFP_KERNEL); + if (!taos) { + err = -ENOMEM; + goto exit; + } + taos->state = TAOS_STATE_INIT; + serio_set_drvdata(serio, taos); + + err = serio_open(serio, drv); + if (err) + goto exit_kfree; + + adapter = &taos->adapter; + adapter->owner = THIS_MODULE; + adapter->algo = &taos_algorithm; + adapter->algo_data = serio; + adapter->dev.parent = &serio->dev; + + /* Reset the TAOS evaluation module to identify it */ + serio_write(serio, TAOS_CMD_RESET); + wait_event_interruptible_timeout(wq, taos->state == TAOS_STATE_IDLE, + msecs_to_jiffies(2000)); + + if (taos->state != TAOS_STATE_IDLE) { + err = -ENODEV; + dev_err(&serio->dev, "TAOS EVM reset failed (state=%d, " + "pos=%d)\n", taos->state, taos->pos); + goto exit_close; + } + + name = taos_adapter_name(taos->buffer); + if (!name) { + err = -ENODEV; + dev_err(&serio->dev, "TAOS EVM identification failed\n"); + goto exit_close; + } + strscpy(adapter->name, name, sizeof(adapter->name)); + + /* Turn echo off for better performance */ + taos->state = TAOS_STATE_EOFF; + serio_write(serio, TAOS_CMD_ECHO_OFF); + + wait_event_interruptible_timeout(wq, taos->state == TAOS_STATE_IDLE, + msecs_to_jiffies(250)); + if (taos->state != TAOS_STATE_IDLE) { + err = -ENODEV; + dev_err(&serio->dev, "TAOS EVM echo off failed " + "(state=%d)\n", taos->state); + goto exit_close; + } + + err = i2c_add_adapter(adapter); + if (err) + goto exit_close; + dev_info(&serio->dev, "Connected to TAOS EVM\n"); + + taos->client = taos_instantiate_device(adapter); + return 0; + + exit_close: + serio_close(serio); + exit_kfree: + kfree(taos); + exit: + return err; +} + +static void taos_disconnect(struct serio *serio) +{ + struct taos_data *taos = serio_get_drvdata(serio); + + i2c_unregister_device(taos->client); + i2c_del_adapter(&taos->adapter); + serio_close(serio); + kfree(taos); + + dev_info(&serio->dev, "Disconnected from TAOS EVM\n"); +} + +static const struct serio_device_id taos_serio_ids[] = { + { + .type = SERIO_RS232, + .proto = SERIO_TAOSEVM, + .id = SERIO_ANY, + .extra = SERIO_ANY, + }, + { 0 } +}; +MODULE_DEVICE_TABLE(serio, taos_serio_ids); + +static struct serio_driver taos_drv = { + .driver = { + .name = "taos-evm", + }, + .description = "TAOS evaluation module driver", + .id_table = taos_serio_ids, + .connect = taos_connect, + .disconnect = taos_disconnect, + .interrupt = taos_interrupt, +}; + +module_serio_driver(taos_drv); + +MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>"); +MODULE_DESCRIPTION("TAOS evaluation module driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-tegra-bpmp.c b/drivers/i2c/busses/i2c-tegra-bpmp.c new file mode 100644 index 000000000..b0840fa0f --- /dev/null +++ b/drivers/i2c/busses/i2c-tegra-bpmp.c @@ -0,0 +1,345 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * drivers/i2c/busses/i2c-tegra-bpmp.c + * + * Copyright (c) 2016 NVIDIA Corporation. All rights reserved. + * + * Author: Shardar Shariff Md <smohammed@nvidia.com> + */ + +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> + +#include <soc/tegra/bpmp-abi.h> +#include <soc/tegra/bpmp.h> + +/* + * Serialized I2C message header size is 6 bytes and includes address, flags + * and length + */ +#define SERIALI2C_HDR_SIZE 6 + +struct tegra_bpmp_i2c { + struct i2c_adapter adapter; + struct device *dev; + + struct tegra_bpmp *bpmp; + unsigned int bus; +}; + +/* + * Linux flags are translated to BPMP defined I2C flags that are used in BPMP + * firmware I2C driver to avoid any issues in future if Linux I2C flags are + * changed. + */ +static void tegra_bpmp_xlate_flags(u16 flags, u16 *out) +{ + if (flags & I2C_M_TEN) + *out |= SERIALI2C_TEN; + + if (flags & I2C_M_RD) + *out |= SERIALI2C_RD; + + if (flags & I2C_M_STOP) + *out |= SERIALI2C_STOP; + + if (flags & I2C_M_NOSTART) + *out |= SERIALI2C_NOSTART; + + if (flags & I2C_M_REV_DIR_ADDR) + *out |= SERIALI2C_REV_DIR_ADDR; + + if (flags & I2C_M_IGNORE_NAK) + *out |= SERIALI2C_IGNORE_NAK; + + if (flags & I2C_M_NO_RD_ACK) + *out |= SERIALI2C_NO_RD_ACK; + + if (flags & I2C_M_RECV_LEN) + *out |= SERIALI2C_RECV_LEN; +} + +/* + * The serialized I2C format is simply the following: + * [addr little-endian][flags little-endian][len little-endian][data if write] + * [addr little-endian][flags little-endian][len little-endian][data if write] + * ... + * + * The flags are translated from Linux kernel representation to seriali2c + * representation. Any undefined flag being set causes an error. + * + * The data is there only for writes. Reads have the data transferred in the + * other direction, and thus data is not present. + * + * See deserialize_i2c documentation for the data format in the other direction. + */ +static void tegra_bpmp_serialize_i2c_msg(struct tegra_bpmp_i2c *i2c, + struct mrq_i2c_request *request, + struct i2c_msg *msgs, + unsigned int num) +{ + char *buf = request->xfer.data_buf; + unsigned int i, j, pos = 0; + + for (i = 0; i < num; i++) { + struct i2c_msg *msg = &msgs[i]; + u16 flags = 0; + + tegra_bpmp_xlate_flags(msg->flags, &flags); + + buf[pos++] = msg->addr & 0xff; + buf[pos++] = (msg->addr & 0xff00) >> 8; + buf[pos++] = flags & 0xff; + buf[pos++] = (flags & 0xff00) >> 8; + buf[pos++] = msg->len & 0xff; + buf[pos++] = (msg->len & 0xff00) >> 8; + + if ((flags & SERIALI2C_RD) == 0) { + for (j = 0; j < msg->len; j++) + buf[pos++] = msg->buf[j]; + } + } + + request->xfer.data_size = pos; +} + +/* + * The data in the BPMP -> CPU direction is composed of sequential blocks for + * those messages that have I2C_M_RD. So, for example, if you have: + * + * - !I2C_M_RD, len == 5, data == a0 01 02 03 04 + * - !I2C_M_RD, len == 1, data == a0 + * - I2C_M_RD, len == 2, data == [uninitialized buffer 1] + * - !I2C_M_RD, len == 1, data == a2 + * - I2C_M_RD, len == 2, data == [uninitialized buffer 2] + * + * ...then the data in the BPMP -> CPU direction would be 4 bytes total, and + * would contain 2 bytes that will go to uninitialized buffer 1, and 2 bytes + * that will go to uninitialized buffer 2. + */ +static int tegra_bpmp_i2c_deserialize(struct tegra_bpmp_i2c *i2c, + struct mrq_i2c_response *response, + struct i2c_msg *msgs, + unsigned int num) +{ + size_t size = response->xfer.data_size, len = 0, pos = 0; + char *buf = response->xfer.data_buf; + unsigned int i; + + for (i = 0; i < num; i++) + if (msgs[i].flags & I2C_M_RD) + len += msgs[i].len; + + if (len != size) + return -EINVAL; + + for (i = 0; i < num; i++) { + if (msgs[i].flags & I2C_M_RD) { + memcpy(msgs[i].buf, buf + pos, msgs[i].len); + pos += msgs[i].len; + } + } + + return 0; +} + +static int tegra_bpmp_i2c_msg_len_check(struct i2c_msg *msgs, unsigned int num) +{ + size_t tx_len = 0, rx_len = 0; + unsigned int i; + + for (i = 0; i < num; i++) + if (!(msgs[i].flags & I2C_M_RD)) + tx_len += SERIALI2C_HDR_SIZE + msgs[i].len; + + if (tx_len > TEGRA_I2C_IPC_MAX_IN_BUF_SIZE) + return -EINVAL; + + for (i = 0; i < num; i++) + if ((msgs[i].flags & I2C_M_RD)) + rx_len += msgs[i].len; + + if (rx_len > TEGRA_I2C_IPC_MAX_OUT_BUF_SIZE) + return -EINVAL; + + return 0; +} + +static int tegra_bpmp_i2c_msg_xfer(struct tegra_bpmp_i2c *i2c, + struct mrq_i2c_request *request, + struct mrq_i2c_response *response, + bool atomic) +{ + struct tegra_bpmp_message msg; + int err; + + request->cmd = CMD_I2C_XFER; + request->xfer.bus_id = i2c->bus; + + memset(&msg, 0, sizeof(msg)); + msg.mrq = MRQ_I2C; + msg.tx.data = request; + msg.tx.size = sizeof(*request); + msg.rx.data = response; + msg.rx.size = sizeof(*response); + + if (atomic) + err = tegra_bpmp_transfer_atomic(i2c->bpmp, &msg); + else + err = tegra_bpmp_transfer(i2c->bpmp, &msg); + + if (err < 0) { + dev_err(i2c->dev, "failed to transfer message: %d\n", err); + return err; + } + + if (msg.rx.ret != 0) { + if (msg.rx.ret == -BPMP_EAGAIN) { + dev_dbg(i2c->dev, "arbitration lost\n"); + return -EAGAIN; + } + + if (msg.rx.ret == -BPMP_ETIMEDOUT) { + dev_dbg(i2c->dev, "timeout\n"); + return -ETIMEDOUT; + } + + if (msg.rx.ret == -BPMP_ENXIO) { + dev_dbg(i2c->dev, "NAK\n"); + return -ENXIO; + } + + dev_err(i2c->dev, "transaction failed: %d\n", msg.rx.ret); + return -EIO; + } + + return 0; +} + +static int tegra_bpmp_i2c_xfer_common(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num, + bool atomic) +{ + struct tegra_bpmp_i2c *i2c = i2c_get_adapdata(adapter); + struct mrq_i2c_response response; + struct mrq_i2c_request request; + int err; + + err = tegra_bpmp_i2c_msg_len_check(msgs, num); + if (err < 0) { + dev_err(i2c->dev, "unsupported message length\n"); + return err; + } + + memset(&request, 0, sizeof(request)); + memset(&response, 0, sizeof(response)); + + tegra_bpmp_serialize_i2c_msg(i2c, &request, msgs, num); + err = tegra_bpmp_i2c_msg_xfer(i2c, &request, &response, atomic); + if (err < 0) { + dev_err(i2c->dev, "failed to transfer message: %d\n", err); + return err; + } + + err = tegra_bpmp_i2c_deserialize(i2c, &response, msgs, num); + if (err < 0) { + dev_err(i2c->dev, "failed to deserialize message: %d\n", err); + return err; + } + + return num; +} + +static int tegra_bpmp_i2c_xfer(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num) +{ + return tegra_bpmp_i2c_xfer_common(adapter, msgs, num, false); +} + +static int tegra_bpmp_i2c_xfer_atomic(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num) +{ + return tegra_bpmp_i2c_xfer_common(adapter, msgs, num, true); +} + +static u32 tegra_bpmp_i2c_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR | + I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART; +} + +static const struct i2c_algorithm tegra_bpmp_i2c_algo = { + .master_xfer = tegra_bpmp_i2c_xfer, + .master_xfer_atomic = tegra_bpmp_i2c_xfer_atomic, + .functionality = tegra_bpmp_i2c_func, +}; + +static int tegra_bpmp_i2c_probe(struct platform_device *pdev) +{ + struct tegra_bpmp_i2c *i2c; + u32 value; + int err; + + i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->dev = &pdev->dev; + + i2c->bpmp = dev_get_drvdata(pdev->dev.parent); + if (!i2c->bpmp) + return -ENODEV; + + err = of_property_read_u32(pdev->dev.of_node, "nvidia,bpmp-bus-id", + &value); + if (err < 0) + return err; + + i2c->bus = value; + + i2c_set_adapdata(&i2c->adapter, i2c); + i2c->adapter.owner = THIS_MODULE; + strscpy(i2c->adapter.name, "Tegra BPMP I2C adapter", + sizeof(i2c->adapter.name)); + i2c->adapter.algo = &tegra_bpmp_i2c_algo; + i2c->adapter.dev.parent = &pdev->dev; + i2c->adapter.dev.of_node = pdev->dev.of_node; + + platform_set_drvdata(pdev, i2c); + + return i2c_add_adapter(&i2c->adapter); +} + +static void tegra_bpmp_i2c_remove(struct platform_device *pdev) +{ + struct tegra_bpmp_i2c *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adapter); +} + +static const struct of_device_id tegra_bpmp_i2c_of_match[] = { + { .compatible = "nvidia,tegra186-bpmp-i2c", }, + { } +}; +MODULE_DEVICE_TABLE(of, tegra_bpmp_i2c_of_match); + +static struct platform_driver tegra_bpmp_i2c_driver = { + .driver = { + .name = "tegra-bpmp-i2c", + .of_match_table = tegra_bpmp_i2c_of_match, + }, + .probe = tegra_bpmp_i2c_probe, + .remove_new = tegra_bpmp_i2c_remove, +}; +module_platform_driver(tegra_bpmp_i2c_driver); + +MODULE_DESCRIPTION("NVIDIA Tegra BPMP I2C bus controller driver"); +MODULE_AUTHOR("Shardar Shariff Md <smohammed@nvidia.com>"); +MODULE_AUTHOR("Juha-Matti Tilli"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c new file mode 100644 index 000000000..920d5a8cb --- /dev/null +++ b/drivers/i2c/busses/i2c-tegra.c @@ -0,0 +1,1981 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * drivers/i2c/busses/i2c-tegra.c + * + * Copyright (C) 2010 Google, Inc. + * Author: Colin Cross <ccross@android.com> + */ + +#include <linux/acpi.h> +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/ktime.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/reset.h> + +#define BYTES_PER_FIFO_WORD 4 + +#define I2C_CNFG 0x000 +#define I2C_CNFG_DEBOUNCE_CNT GENMASK(14, 12) +#define I2C_CNFG_PACKET_MODE_EN BIT(10) +#define I2C_CNFG_NEW_MASTER_FSM BIT(11) +#define I2C_CNFG_MULTI_MASTER_MODE BIT(17) +#define I2C_STATUS 0x01c +#define I2C_SL_CNFG 0x020 +#define I2C_SL_CNFG_NACK BIT(1) +#define I2C_SL_CNFG_NEWSL BIT(2) +#define I2C_SL_ADDR1 0x02c +#define I2C_SL_ADDR2 0x030 +#define I2C_TLOW_SEXT 0x034 +#define I2C_TX_FIFO 0x050 +#define I2C_RX_FIFO 0x054 +#define I2C_PACKET_TRANSFER_STATUS 0x058 +#define I2C_FIFO_CONTROL 0x05c +#define I2C_FIFO_CONTROL_TX_FLUSH BIT(1) +#define I2C_FIFO_CONTROL_RX_FLUSH BIT(0) +#define I2C_FIFO_CONTROL_TX_TRIG(x) (((x) - 1) << 5) +#define I2C_FIFO_CONTROL_RX_TRIG(x) (((x) - 1) << 2) +#define I2C_FIFO_STATUS 0x060 +#define I2C_FIFO_STATUS_TX GENMASK(7, 4) +#define I2C_FIFO_STATUS_RX GENMASK(3, 0) +#define I2C_INT_MASK 0x064 +#define I2C_INT_STATUS 0x068 +#define I2C_INT_BUS_CLR_DONE BIT(11) +#define I2C_INT_PACKET_XFER_COMPLETE BIT(7) +#define I2C_INT_NO_ACK BIT(3) +#define I2C_INT_ARBITRATION_LOST BIT(2) +#define I2C_INT_TX_FIFO_DATA_REQ BIT(1) +#define I2C_INT_RX_FIFO_DATA_REQ BIT(0) +#define I2C_CLK_DIVISOR 0x06c +#define I2C_CLK_DIVISOR_STD_FAST_MODE GENMASK(31, 16) +#define I2C_CLK_DIVISOR_HSMODE GENMASK(15, 0) + +#define DVC_CTRL_REG1 0x000 +#define DVC_CTRL_REG1_INTR_EN BIT(10) +#define DVC_CTRL_REG3 0x008 +#define DVC_CTRL_REG3_SW_PROG BIT(26) +#define DVC_CTRL_REG3_I2C_DONE_INTR_EN BIT(30) +#define DVC_STATUS 0x00c +#define DVC_STATUS_I2C_DONE_INTR BIT(30) + +#define I2C_ERR_NONE 0x00 +#define I2C_ERR_NO_ACK BIT(0) +#define I2C_ERR_ARBITRATION_LOST BIT(1) +#define I2C_ERR_UNKNOWN_INTERRUPT BIT(2) +#define I2C_ERR_RX_BUFFER_OVERFLOW BIT(3) + +#define PACKET_HEADER0_HEADER_SIZE GENMASK(29, 28) +#define PACKET_HEADER0_PACKET_ID GENMASK(23, 16) +#define PACKET_HEADER0_CONT_ID GENMASK(15, 12) +#define PACKET_HEADER0_PROTOCOL GENMASK(7, 4) +#define PACKET_HEADER0_PROTOCOL_I2C 1 + +#define I2C_HEADER_CONT_ON_NAK BIT(21) +#define I2C_HEADER_READ BIT(19) +#define I2C_HEADER_10BIT_ADDR BIT(18) +#define I2C_HEADER_IE_ENABLE BIT(17) +#define I2C_HEADER_REPEAT_START BIT(16) +#define I2C_HEADER_CONTINUE_XFER BIT(15) +#define I2C_HEADER_SLAVE_ADDR_SHIFT 1 + +#define I2C_BUS_CLEAR_CNFG 0x084 +#define I2C_BC_SCLK_THRESHOLD GENMASK(23, 16) +#define I2C_BC_STOP_COND BIT(2) +#define I2C_BC_TERMINATE BIT(1) +#define I2C_BC_ENABLE BIT(0) +#define I2C_BUS_CLEAR_STATUS 0x088 +#define I2C_BC_STATUS BIT(0) + +#define I2C_CONFIG_LOAD 0x08c +#define I2C_MSTR_CONFIG_LOAD BIT(0) + +#define I2C_CLKEN_OVERRIDE 0x090 +#define I2C_MST_CORE_CLKEN_OVR BIT(0) + +#define I2C_INTERFACE_TIMING_0 0x094 +#define I2C_INTERFACE_TIMING_THIGH GENMASK(13, 8) +#define I2C_INTERFACE_TIMING_TLOW GENMASK(5, 0) +#define I2C_INTERFACE_TIMING_1 0x098 +#define I2C_INTERFACE_TIMING_TBUF GENMASK(29, 24) +#define I2C_INTERFACE_TIMING_TSU_STO GENMASK(21, 16) +#define I2C_INTERFACE_TIMING_THD_STA GENMASK(13, 8) +#define I2C_INTERFACE_TIMING_TSU_STA GENMASK(5, 0) + +#define I2C_HS_INTERFACE_TIMING_0 0x09c +#define I2C_HS_INTERFACE_TIMING_THIGH GENMASK(13, 8) +#define I2C_HS_INTERFACE_TIMING_TLOW GENMASK(5, 0) +#define I2C_HS_INTERFACE_TIMING_1 0x0a0 +#define I2C_HS_INTERFACE_TIMING_TSU_STO GENMASK(21, 16) +#define I2C_HS_INTERFACE_TIMING_THD_STA GENMASK(13, 8) +#define I2C_HS_INTERFACE_TIMING_TSU_STA GENMASK(5, 0) + +#define I2C_MST_FIFO_CONTROL 0x0b4 +#define I2C_MST_FIFO_CONTROL_RX_FLUSH BIT(0) +#define I2C_MST_FIFO_CONTROL_TX_FLUSH BIT(1) +#define I2C_MST_FIFO_CONTROL_RX_TRIG(x) (((x) - 1) << 4) +#define I2C_MST_FIFO_CONTROL_TX_TRIG(x) (((x) - 1) << 16) + +#define I2C_MST_FIFO_STATUS 0x0b8 +#define I2C_MST_FIFO_STATUS_TX GENMASK(23, 16) +#define I2C_MST_FIFO_STATUS_RX GENMASK(7, 0) + +/* configuration load timeout in microseconds */ +#define I2C_CONFIG_LOAD_TIMEOUT 1000000 + +/* packet header size in bytes */ +#define I2C_PACKET_HEADER_SIZE 12 + +/* + * I2C Controller will use PIO mode for transfers up to 32 bytes in order to + * avoid DMA overhead, otherwise external APB DMA controller will be used. + * Note that the actual MAX PIO length is 20 bytes because 32 bytes include + * I2C_PACKET_HEADER_SIZE. + */ +#define I2C_PIO_MODE_PREFERRED_LEN 32 + +/* + * msg_end_type: The bus control which needs to be sent at end of transfer. + * @MSG_END_STOP: Send stop pulse. + * @MSG_END_REPEAT_START: Send repeat-start. + * @MSG_END_CONTINUE: Don't send stop or repeat-start. + */ +enum msg_end_type { + MSG_END_STOP, + MSG_END_REPEAT_START, + MSG_END_CONTINUE, +}; + +/** + * struct tegra_i2c_hw_feature : per hardware generation features + * @has_continue_xfer_support: continue-transfer supported + * @has_per_pkt_xfer_complete_irq: Has enable/disable capability for transfer + * completion interrupt on per packet basis. + * @has_config_load_reg: Has the config load register to load the new + * configuration. + * @clk_divisor_hs_mode: Clock divisor in HS mode. + * @clk_divisor_std_mode: Clock divisor in standard mode. It is + * applicable if there is no fast clock source i.e. single clock + * source. + * @clk_divisor_fast_mode: Clock divisor in fast mode. It is + * applicable if there is no fast clock source i.e. single clock + * source. + * @clk_divisor_fast_plus_mode: Clock divisor in fast mode plus. It is + * applicable if there is no fast clock source (i.e. single + * clock source). + * @has_multi_master_mode: The I2C controller supports running in single-master + * or multi-master mode. + * @has_slcg_override_reg: The I2C controller supports a register that + * overrides the second level clock gating. + * @has_mst_fifo: The I2C controller contains the new MST FIFO interface that + * provides additional features and allows for longer messages to + * be transferred in one go. + * @quirks: I2C adapter quirks for limiting write/read transfer size and not + * allowing 0 length transfers. + * @supports_bus_clear: Bus Clear support to recover from bus hang during + * SDA stuck low from device for some unknown reasons. + * @has_apb_dma: Support of APBDMA on corresponding Tegra chip. + * @tlow_std_mode: Low period of the clock in standard mode. + * @thigh_std_mode: High period of the clock in standard mode. + * @tlow_fast_fastplus_mode: Low period of the clock in fast/fast-plus modes. + * @thigh_fast_fastplus_mode: High period of the clock in fast/fast-plus modes. + * @setup_hold_time_std_mode: Setup and hold time for start and stop conditions + * in standard mode. + * @setup_hold_time_fast_fast_plus_mode: Setup and hold time for start and stop + * conditions in fast/fast-plus modes. + * @setup_hold_time_hs_mode: Setup and hold time for start and stop conditions + * in HS mode. + * @has_interface_timing_reg: Has interface timing register to program the tuned + * timing settings. + */ +struct tegra_i2c_hw_feature { + bool has_continue_xfer_support; + bool has_per_pkt_xfer_complete_irq; + bool has_config_load_reg; + u32 clk_divisor_hs_mode; + u32 clk_divisor_std_mode; + u32 clk_divisor_fast_mode; + u32 clk_divisor_fast_plus_mode; + bool has_multi_master_mode; + bool has_slcg_override_reg; + bool has_mst_fifo; + const struct i2c_adapter_quirks *quirks; + bool supports_bus_clear; + bool has_apb_dma; + u32 tlow_std_mode; + u32 thigh_std_mode; + u32 tlow_fast_fastplus_mode; + u32 thigh_fast_fastplus_mode; + u32 setup_hold_time_std_mode; + u32 setup_hold_time_fast_fast_plus_mode; + u32 setup_hold_time_hs_mode; + bool has_interface_timing_reg; +}; + +/** + * struct tegra_i2c_dev - per device I2C context + * @dev: device reference for power management + * @hw: Tegra I2C HW feature + * @adapter: core I2C layer adapter information + * @div_clk: clock reference for div clock of I2C controller + * @clocks: array of I2C controller clocks + * @nclocks: number of clocks in the array + * @rst: reset control for the I2C controller + * @base: ioremapped registers cookie + * @base_phys: physical base address of the I2C controller + * @cont_id: I2C controller ID, used for packet header + * @irq: IRQ number of transfer complete interrupt + * @is_dvc: identifies the DVC I2C controller, has a different register layout + * @is_vi: identifies the VI I2C controller, has a different register layout + * @msg_complete: transfer completion notifier + * @msg_buf_remaining: size of unsent data in the message buffer + * @msg_len: length of message in current transfer + * @msg_err: error code for completed message + * @msg_buf: pointer to current message data + * @msg_read: indicates that the transfer is a read access + * @timings: i2c timings information like bus frequency + * @multimaster_mode: indicates that I2C controller is in multi-master mode + * @dma_chan: DMA channel + * @dma_phys: handle to DMA resources + * @dma_buf: pointer to allocated DMA buffer + * @dma_buf_size: DMA buffer size + * @dma_mode: indicates active DMA transfer + * @dma_complete: DMA completion notifier + * @atomic_mode: indicates active atomic transfer + */ +struct tegra_i2c_dev { + struct device *dev; + struct i2c_adapter adapter; + + const struct tegra_i2c_hw_feature *hw; + struct reset_control *rst; + unsigned int cont_id; + unsigned int irq; + + phys_addr_t base_phys; + void __iomem *base; + + struct clk_bulk_data clocks[2]; + unsigned int nclocks; + + struct clk *div_clk; + struct i2c_timings timings; + + struct completion msg_complete; + size_t msg_buf_remaining; + unsigned int msg_len; + int msg_err; + u8 *msg_buf; + + struct completion dma_complete; + struct dma_chan *dma_chan; + unsigned int dma_buf_size; + struct device *dma_dev; + dma_addr_t dma_phys; + void *dma_buf; + + bool multimaster_mode; + bool atomic_mode; + bool dma_mode; + bool msg_read; + bool is_dvc; + bool is_vi; +}; + +#define IS_DVC(dev) (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC) && (dev)->is_dvc) +#define IS_VI(dev) (IS_ENABLED(CONFIG_ARCH_TEGRA_210_SOC) && (dev)->is_vi) + +static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val, + unsigned int reg) +{ + writel_relaxed(val, i2c_dev->base + reg); +} + +static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, unsigned int reg) +{ + return readl_relaxed(i2c_dev->base + reg); +} + +/* + * If necessary, i2c_writel() and i2c_readl() will offset the register + * in order to talk to the I2C block inside the DVC block. + */ +static u32 tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev, unsigned int reg) +{ + if (IS_DVC(i2c_dev)) + reg += (reg >= I2C_TX_FIFO) ? 0x10 : 0x40; + else if (IS_VI(i2c_dev)) + reg = 0xc00 + (reg << 2); + + return reg; +} + +static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val, unsigned int reg) +{ + writel_relaxed(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); + + /* read back register to make sure that register writes completed */ + if (reg != I2C_TX_FIFO) + readl_relaxed(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); + else if (IS_VI(i2c_dev)) + readl_relaxed(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, I2C_INT_STATUS)); +} + +static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned int reg) +{ + return readl_relaxed(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg)); +} + +static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data, + unsigned int reg, unsigned int len) +{ + writesl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len); +} + +static void i2c_writesl_vi(struct tegra_i2c_dev *i2c_dev, void *data, + unsigned int reg, unsigned int len) +{ + u32 *data32 = data; + + /* + * VI I2C controller has known hardware bug where writes get stuck + * when immediate multiple writes happen to TX_FIFO register. + * Recommended software work around is to read I2C register after + * each write to TX_FIFO register to flush out the data. + */ + while (len--) + i2c_writel(i2c_dev, *data32++, reg); +} + +static void i2c_readsl(struct tegra_i2c_dev *i2c_dev, void *data, + unsigned int reg, unsigned int len) +{ + readsl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len); +} + +static void tegra_i2c_mask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask) +{ + u32 int_mask; + + int_mask = i2c_readl(i2c_dev, I2C_INT_MASK) & ~mask; + i2c_writel(i2c_dev, int_mask, I2C_INT_MASK); +} + +static void tegra_i2c_unmask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask) +{ + u32 int_mask; + + int_mask = i2c_readl(i2c_dev, I2C_INT_MASK) | mask; + i2c_writel(i2c_dev, int_mask, I2C_INT_MASK); +} + +static void tegra_i2c_dma_complete(void *args) +{ + struct tegra_i2c_dev *i2c_dev = args; + + complete(&i2c_dev->dma_complete); +} + +static int tegra_i2c_dma_submit(struct tegra_i2c_dev *i2c_dev, size_t len) +{ + struct dma_async_tx_descriptor *dma_desc; + enum dma_transfer_direction dir; + + dev_dbg(i2c_dev->dev, "starting DMA for length: %zu\n", len); + + reinit_completion(&i2c_dev->dma_complete); + + dir = i2c_dev->msg_read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV; + + dma_desc = dmaengine_prep_slave_single(i2c_dev->dma_chan, i2c_dev->dma_phys, + len, dir, DMA_PREP_INTERRUPT | + DMA_CTRL_ACK); + if (!dma_desc) { + dev_err(i2c_dev->dev, "failed to get %s DMA descriptor\n", + i2c_dev->msg_read ? "RX" : "TX"); + return -EINVAL; + } + + dma_desc->callback = tegra_i2c_dma_complete; + dma_desc->callback_param = i2c_dev; + + dmaengine_submit(dma_desc); + dma_async_issue_pending(i2c_dev->dma_chan); + + return 0; +} + +static void tegra_i2c_release_dma(struct tegra_i2c_dev *i2c_dev) +{ + if (i2c_dev->dma_buf) { + dma_free_coherent(i2c_dev->dma_dev, i2c_dev->dma_buf_size, + i2c_dev->dma_buf, i2c_dev->dma_phys); + i2c_dev->dma_buf = NULL; + } + + if (i2c_dev->dma_chan) { + dma_release_channel(i2c_dev->dma_chan); + i2c_dev->dma_chan = NULL; + } +} + +static int tegra_i2c_init_dma(struct tegra_i2c_dev *i2c_dev) +{ + dma_addr_t dma_phys; + u32 *dma_buf; + int err; + + if (IS_VI(i2c_dev)) + return 0; + + if (i2c_dev->hw->has_apb_dma) { + if (!IS_ENABLED(CONFIG_TEGRA20_APB_DMA)) { + dev_dbg(i2c_dev->dev, "APB DMA support not enabled\n"); + return 0; + } + } else if (!IS_ENABLED(CONFIG_TEGRA186_GPC_DMA)) { + dev_dbg(i2c_dev->dev, "GPC DMA support not enabled\n"); + return 0; + } + + /* + * The same channel will be used for both RX and TX. + * Keeping the name as "tx" for backward compatibility + * with existing devicetrees. + */ + i2c_dev->dma_chan = dma_request_chan(i2c_dev->dev, "tx"); + if (IS_ERR(i2c_dev->dma_chan)) { + err = PTR_ERR(i2c_dev->dma_chan); + i2c_dev->dma_chan = NULL; + goto err_out; + } + + i2c_dev->dma_dev = i2c_dev->dma_chan->device->dev; + i2c_dev->dma_buf_size = i2c_dev->hw->quirks->max_write_len + + I2C_PACKET_HEADER_SIZE; + + dma_buf = dma_alloc_coherent(i2c_dev->dma_dev, i2c_dev->dma_buf_size, + &dma_phys, GFP_KERNEL | __GFP_NOWARN); + if (!dma_buf) { + dev_err(i2c_dev->dev, "failed to allocate DMA buffer\n"); + err = -ENOMEM; + goto err_out; + } + + i2c_dev->dma_buf = dma_buf; + i2c_dev->dma_phys = dma_phys; + + return 0; + +err_out: + tegra_i2c_release_dma(i2c_dev); + if (err != -EPROBE_DEFER) { + dev_err(i2c_dev->dev, "cannot use DMA: %d\n", err); + dev_err(i2c_dev->dev, "falling back to PIO\n"); + return 0; + } + + return err; +} + +/* + * One of the Tegra I2C blocks is inside the DVC (Digital Voltage Controller) + * block. This block is identical to the rest of the I2C blocks, except that + * it only supports master mode, it has registers moved around, and it needs + * some extra init to get it into I2C mode. The register moves are handled + * by i2c_readl() and i2c_writel(). + */ +static void tegra_dvc_init(struct tegra_i2c_dev *i2c_dev) +{ + u32 val; + + val = dvc_readl(i2c_dev, DVC_CTRL_REG3); + val |= DVC_CTRL_REG3_SW_PROG; + val |= DVC_CTRL_REG3_I2C_DONE_INTR_EN; + dvc_writel(i2c_dev, val, DVC_CTRL_REG3); + + val = dvc_readl(i2c_dev, DVC_CTRL_REG1); + val |= DVC_CTRL_REG1_INTR_EN; + dvc_writel(i2c_dev, val, DVC_CTRL_REG1); +} + +static void tegra_i2c_vi_init(struct tegra_i2c_dev *i2c_dev) +{ + u32 value; + + value = FIELD_PREP(I2C_INTERFACE_TIMING_THIGH, 2) | + FIELD_PREP(I2C_INTERFACE_TIMING_TLOW, 4); + i2c_writel(i2c_dev, value, I2C_INTERFACE_TIMING_0); + + value = FIELD_PREP(I2C_INTERFACE_TIMING_TBUF, 4) | + FIELD_PREP(I2C_INTERFACE_TIMING_TSU_STO, 7) | + FIELD_PREP(I2C_INTERFACE_TIMING_THD_STA, 4) | + FIELD_PREP(I2C_INTERFACE_TIMING_TSU_STA, 4); + i2c_writel(i2c_dev, value, I2C_INTERFACE_TIMING_1); + + value = FIELD_PREP(I2C_HS_INTERFACE_TIMING_THIGH, 3) | + FIELD_PREP(I2C_HS_INTERFACE_TIMING_TLOW, 8); + i2c_writel(i2c_dev, value, I2C_HS_INTERFACE_TIMING_0); + + value = FIELD_PREP(I2C_HS_INTERFACE_TIMING_TSU_STO, 11) | + FIELD_PREP(I2C_HS_INTERFACE_TIMING_THD_STA, 11) | + FIELD_PREP(I2C_HS_INTERFACE_TIMING_TSU_STA, 11); + i2c_writel(i2c_dev, value, I2C_HS_INTERFACE_TIMING_1); + + value = FIELD_PREP(I2C_BC_SCLK_THRESHOLD, 9) | I2C_BC_STOP_COND; + i2c_writel(i2c_dev, value, I2C_BUS_CLEAR_CNFG); + + i2c_writel(i2c_dev, 0x0, I2C_TLOW_SEXT); +} + +static int tegra_i2c_poll_register(struct tegra_i2c_dev *i2c_dev, + u32 reg, u32 mask, u32 delay_us, + u32 timeout_us) +{ + void __iomem *addr = i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg); + u32 val; + + if (!i2c_dev->atomic_mode) + return readl_relaxed_poll_timeout(addr, val, !(val & mask), + delay_us, timeout_us); + + return readl_relaxed_poll_timeout_atomic(addr, val, !(val & mask), + delay_us, timeout_us); +} + +static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev) +{ + u32 mask, val, offset; + int err; + + if (i2c_dev->hw->has_mst_fifo) { + mask = I2C_MST_FIFO_CONTROL_TX_FLUSH | + I2C_MST_FIFO_CONTROL_RX_FLUSH; + offset = I2C_MST_FIFO_CONTROL; + } else { + mask = I2C_FIFO_CONTROL_TX_FLUSH | + I2C_FIFO_CONTROL_RX_FLUSH; + offset = I2C_FIFO_CONTROL; + } + + val = i2c_readl(i2c_dev, offset); + val |= mask; + i2c_writel(i2c_dev, val, offset); + + err = tegra_i2c_poll_register(i2c_dev, offset, mask, 1000, 1000000); + if (err) { + dev_err(i2c_dev->dev, "failed to flush FIFO\n"); + return err; + } + + return 0; +} + +static int tegra_i2c_wait_for_config_load(struct tegra_i2c_dev *i2c_dev) +{ + int err; + + if (!i2c_dev->hw->has_config_load_reg) + return 0; + + i2c_writel(i2c_dev, I2C_MSTR_CONFIG_LOAD, I2C_CONFIG_LOAD); + + err = tegra_i2c_poll_register(i2c_dev, I2C_CONFIG_LOAD, 0xffffffff, + 1000, I2C_CONFIG_LOAD_TIMEOUT); + if (err) { + dev_err(i2c_dev->dev, "failed to load config\n"); + return err; + } + + return 0; +} + +static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev) +{ + u32 val, clk_divisor, clk_multiplier, tsu_thd, tlow, thigh, non_hs_mode; + acpi_handle handle = ACPI_HANDLE(i2c_dev->dev); + struct i2c_timings *t = &i2c_dev->timings; + int err; + + /* + * The reset shouldn't ever fail in practice. The failure will be a + * sign of a severe problem that needs to be resolved. Still we don't + * want to fail the initialization completely because this may break + * kernel boot up since voltage regulators use I2C. Hence, we will + * emit a noisy warning on error, which won't stay unnoticed and + * won't hose machine entirely. + */ + if (handle) + err = acpi_evaluate_object(handle, "_RST", NULL, NULL); + else + err = reset_control_reset(i2c_dev->rst); + + WARN_ON_ONCE(err); + + if (IS_DVC(i2c_dev)) + tegra_dvc_init(i2c_dev); + + val = I2C_CNFG_NEW_MASTER_FSM | I2C_CNFG_PACKET_MODE_EN | + FIELD_PREP(I2C_CNFG_DEBOUNCE_CNT, 2); + + if (i2c_dev->hw->has_multi_master_mode) + val |= I2C_CNFG_MULTI_MASTER_MODE; + + i2c_writel(i2c_dev, val, I2C_CNFG); + i2c_writel(i2c_dev, 0, I2C_INT_MASK); + + if (IS_VI(i2c_dev)) + tegra_i2c_vi_init(i2c_dev); + + switch (t->bus_freq_hz) { + case I2C_MAX_STANDARD_MODE_FREQ + 1 ... I2C_MAX_FAST_MODE_PLUS_FREQ: + default: + tlow = i2c_dev->hw->tlow_fast_fastplus_mode; + thigh = i2c_dev->hw->thigh_fast_fastplus_mode; + tsu_thd = i2c_dev->hw->setup_hold_time_fast_fast_plus_mode; + + if (t->bus_freq_hz > I2C_MAX_FAST_MODE_FREQ) + non_hs_mode = i2c_dev->hw->clk_divisor_fast_plus_mode; + else + non_hs_mode = i2c_dev->hw->clk_divisor_fast_mode; + break; + + case 0 ... I2C_MAX_STANDARD_MODE_FREQ: + tlow = i2c_dev->hw->tlow_std_mode; + thigh = i2c_dev->hw->thigh_std_mode; + tsu_thd = i2c_dev->hw->setup_hold_time_std_mode; + non_hs_mode = i2c_dev->hw->clk_divisor_std_mode; + break; + } + + /* make sure clock divisor programmed correctly */ + clk_divisor = FIELD_PREP(I2C_CLK_DIVISOR_HSMODE, + i2c_dev->hw->clk_divisor_hs_mode) | + FIELD_PREP(I2C_CLK_DIVISOR_STD_FAST_MODE, non_hs_mode); + i2c_writel(i2c_dev, clk_divisor, I2C_CLK_DIVISOR); + + if (i2c_dev->hw->has_interface_timing_reg) { + val = FIELD_PREP(I2C_INTERFACE_TIMING_THIGH, thigh) | + FIELD_PREP(I2C_INTERFACE_TIMING_TLOW, tlow); + i2c_writel(i2c_dev, val, I2C_INTERFACE_TIMING_0); + } + + /* + * Configure setup and hold times only when tsu_thd is non-zero. + * Otherwise, preserve the chip default values. + */ + if (i2c_dev->hw->has_interface_timing_reg && tsu_thd) + i2c_writel(i2c_dev, tsu_thd, I2C_INTERFACE_TIMING_1); + + clk_multiplier = (tlow + thigh + 2) * (non_hs_mode + 1); + + err = clk_set_rate(i2c_dev->div_clk, + t->bus_freq_hz * clk_multiplier); + if (err) { + dev_err(i2c_dev->dev, "failed to set div-clk rate: %d\n", err); + return err; + } + + if (!IS_DVC(i2c_dev) && !IS_VI(i2c_dev)) { + u32 sl_cfg = i2c_readl(i2c_dev, I2C_SL_CNFG); + + sl_cfg |= I2C_SL_CNFG_NACK | I2C_SL_CNFG_NEWSL; + i2c_writel(i2c_dev, sl_cfg, I2C_SL_CNFG); + i2c_writel(i2c_dev, 0xfc, I2C_SL_ADDR1); + i2c_writel(i2c_dev, 0x00, I2C_SL_ADDR2); + } + + err = tegra_i2c_flush_fifos(i2c_dev); + if (err) + return err; + + if (i2c_dev->multimaster_mode && i2c_dev->hw->has_slcg_override_reg) + i2c_writel(i2c_dev, I2C_MST_CORE_CLKEN_OVR, I2C_CLKEN_OVERRIDE); + + err = tegra_i2c_wait_for_config_load(i2c_dev); + if (err) + return err; + + return 0; +} + +static int tegra_i2c_disable_packet_mode(struct tegra_i2c_dev *i2c_dev) +{ + u32 cnfg; + + /* + * NACK interrupt is generated before the I2C controller generates + * the STOP condition on the bus. So, wait for 2 clock periods + * before disabling the controller so that the STOP condition has + * been delivered properly. + */ + udelay(DIV_ROUND_UP(2 * 1000000, i2c_dev->timings.bus_freq_hz)); + + cnfg = i2c_readl(i2c_dev, I2C_CNFG); + if (cnfg & I2C_CNFG_PACKET_MODE_EN) + i2c_writel(i2c_dev, cnfg & ~I2C_CNFG_PACKET_MODE_EN, I2C_CNFG); + + return tegra_i2c_wait_for_config_load(i2c_dev); +} + +static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev) +{ + size_t buf_remaining = i2c_dev->msg_buf_remaining; + unsigned int words_to_transfer, rx_fifo_avail; + u8 *buf = i2c_dev->msg_buf; + u32 val; + + /* + * Catch overflow due to message fully sent before the check for + * RX FIFO availability. + */ + if (WARN_ON_ONCE(!(i2c_dev->msg_buf_remaining))) + return -EINVAL; + + if (i2c_dev->hw->has_mst_fifo) { + val = i2c_readl(i2c_dev, I2C_MST_FIFO_STATUS); + rx_fifo_avail = FIELD_GET(I2C_MST_FIFO_STATUS_RX, val); + } else { + val = i2c_readl(i2c_dev, I2C_FIFO_STATUS); + rx_fifo_avail = FIELD_GET(I2C_FIFO_STATUS_RX, val); + } + + /* round down to exclude partial word at the end of buffer */ + words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; + if (words_to_transfer > rx_fifo_avail) + words_to_transfer = rx_fifo_avail; + + i2c_readsl(i2c_dev, buf, I2C_RX_FIFO, words_to_transfer); + + buf += words_to_transfer * BYTES_PER_FIFO_WORD; + buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; + rx_fifo_avail -= words_to_transfer; + + /* + * If there is a partial word at the end of buffer, handle it + * manually to prevent overwriting past the end of buffer. + */ + if (rx_fifo_avail > 0 && buf_remaining > 0) { + /* + * buf_remaining > 3 check not needed as rx_fifo_avail == 0 + * when (words_to_transfer was > rx_fifo_avail) earlier + * in this function. + */ + val = i2c_readl(i2c_dev, I2C_RX_FIFO); + val = cpu_to_le32(val); + memcpy(buf, &val, buf_remaining); + buf_remaining = 0; + rx_fifo_avail--; + } + + /* RX FIFO must be drained, otherwise it's an Overflow case. */ + if (WARN_ON_ONCE(rx_fifo_avail)) + return -EINVAL; + + i2c_dev->msg_buf_remaining = buf_remaining; + i2c_dev->msg_buf = buf; + + return 0; +} + +static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev) +{ + size_t buf_remaining = i2c_dev->msg_buf_remaining; + unsigned int words_to_transfer, tx_fifo_avail; + u8 *buf = i2c_dev->msg_buf; + u32 val; + + if (i2c_dev->hw->has_mst_fifo) { + val = i2c_readl(i2c_dev, I2C_MST_FIFO_STATUS); + tx_fifo_avail = FIELD_GET(I2C_MST_FIFO_STATUS_TX, val); + } else { + val = i2c_readl(i2c_dev, I2C_FIFO_STATUS); + tx_fifo_avail = FIELD_GET(I2C_FIFO_STATUS_TX, val); + } + + /* round down to exclude partial word at the end of buffer */ + words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD; + + /* + * This hunk pushes 4 bytes at a time into the TX FIFO. + * + * It's very common to have < 4 bytes, hence there is no word + * to push if we have less than 4 bytes to transfer. + */ + if (words_to_transfer) { + if (words_to_transfer > tx_fifo_avail) + words_to_transfer = tx_fifo_avail; + + /* + * Update state before writing to FIFO. Note that this may + * cause us to finish writing all bytes (AKA buf_remaining + * goes to 0), hence we have a potential for an interrupt + * (PACKET_XFER_COMPLETE is not maskable), but GIC interrupt + * is disabled at this point. + */ + buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD; + tx_fifo_avail -= words_to_transfer; + + i2c_dev->msg_buf_remaining = buf_remaining; + i2c_dev->msg_buf = buf + words_to_transfer * BYTES_PER_FIFO_WORD; + + if (IS_VI(i2c_dev)) + i2c_writesl_vi(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer); + else + i2c_writesl(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer); + + buf += words_to_transfer * BYTES_PER_FIFO_WORD; + } + + /* + * If there is a partial word at the end of buffer, handle it manually + * to prevent reading past the end of buffer, which could cross a page + * boundary and fault. + */ + if (tx_fifo_avail > 0 && buf_remaining > 0) { + /* + * buf_remaining > 3 check not needed as tx_fifo_avail == 0 + * when (words_to_transfer was > tx_fifo_avail) earlier + * in this function for non-zero words_to_transfer. + */ + memcpy(&val, buf, buf_remaining); + val = le32_to_cpu(val); + + i2c_dev->msg_buf_remaining = 0; + i2c_dev->msg_buf = NULL; + + i2c_writel(i2c_dev, val, I2C_TX_FIFO); + } + + return 0; +} + +static irqreturn_t tegra_i2c_isr(int irq, void *dev_id) +{ + const u32 status_err = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; + struct tegra_i2c_dev *i2c_dev = dev_id; + u32 status; + + status = i2c_readl(i2c_dev, I2C_INT_STATUS); + + if (status == 0) { + dev_warn(i2c_dev->dev, "IRQ status 0 %08x %08x %08x\n", + i2c_readl(i2c_dev, I2C_PACKET_TRANSFER_STATUS), + i2c_readl(i2c_dev, I2C_STATUS), + i2c_readl(i2c_dev, I2C_CNFG)); + i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT; + goto err; + } + + if (status & status_err) { + tegra_i2c_disable_packet_mode(i2c_dev); + if (status & I2C_INT_NO_ACK) + i2c_dev->msg_err |= I2C_ERR_NO_ACK; + if (status & I2C_INT_ARBITRATION_LOST) + i2c_dev->msg_err |= I2C_ERR_ARBITRATION_LOST; + goto err; + } + + /* + * I2C transfer is terminated during the bus clear, so skip + * processing the other interrupts. + */ + if (i2c_dev->hw->supports_bus_clear && (status & I2C_INT_BUS_CLR_DONE)) + goto err; + + if (!i2c_dev->dma_mode) { + if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) { + if (tegra_i2c_empty_rx_fifo(i2c_dev)) { + /* + * Overflow error condition: message fully sent, + * with no XFER_COMPLETE interrupt but hardware + * asks to transfer more. + */ + i2c_dev->msg_err |= I2C_ERR_RX_BUFFER_OVERFLOW; + goto err; + } + } + + if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) { + if (i2c_dev->msg_buf_remaining) + tegra_i2c_fill_tx_fifo(i2c_dev); + else + tegra_i2c_mask_irq(i2c_dev, + I2C_INT_TX_FIFO_DATA_REQ); + } + } + + i2c_writel(i2c_dev, status, I2C_INT_STATUS); + if (IS_DVC(i2c_dev)) + dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); + + /* + * During message read XFER_COMPLETE interrupt is triggered prior to + * DMA completion and during message write XFER_COMPLETE interrupt is + * triggered after DMA completion. + * + * PACKETS_XFER_COMPLETE indicates completion of all bytes of transfer, + * so forcing msg_buf_remaining to 0 in DMA mode. + */ + if (status & I2C_INT_PACKET_XFER_COMPLETE) { + if (i2c_dev->dma_mode) + i2c_dev->msg_buf_remaining = 0; + /* + * Underflow error condition: XFER_COMPLETE before message + * fully sent. + */ + if (WARN_ON_ONCE(i2c_dev->msg_buf_remaining)) { + i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT; + goto err; + } + complete(&i2c_dev->msg_complete); + } + goto done; +err: + /* mask all interrupts on error */ + tegra_i2c_mask_irq(i2c_dev, + I2C_INT_NO_ACK | + I2C_INT_ARBITRATION_LOST | + I2C_INT_PACKET_XFER_COMPLETE | + I2C_INT_TX_FIFO_DATA_REQ | + I2C_INT_RX_FIFO_DATA_REQ); + + if (i2c_dev->hw->supports_bus_clear) + tegra_i2c_mask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); + + i2c_writel(i2c_dev, status, I2C_INT_STATUS); + + if (IS_DVC(i2c_dev)) + dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS); + + if (i2c_dev->dma_mode) { + dmaengine_terminate_async(i2c_dev->dma_chan); + complete(&i2c_dev->dma_complete); + } + + complete(&i2c_dev->msg_complete); +done: + return IRQ_HANDLED; +} + +static void tegra_i2c_config_fifo_trig(struct tegra_i2c_dev *i2c_dev, + size_t len) +{ + struct dma_slave_config slv_config = {0}; + u32 val, reg, dma_burst, reg_offset; + int err; + + if (i2c_dev->hw->has_mst_fifo) + reg = I2C_MST_FIFO_CONTROL; + else + reg = I2C_FIFO_CONTROL; + + if (i2c_dev->dma_mode) { + if (len & 0xF) + dma_burst = 1; + else if (len & 0x10) + dma_burst = 4; + else + dma_burst = 8; + + if (i2c_dev->msg_read) { + reg_offset = tegra_i2c_reg_addr(i2c_dev, I2C_RX_FIFO); + + slv_config.src_addr = i2c_dev->base_phys + reg_offset; + slv_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + slv_config.src_maxburst = dma_burst; + + if (i2c_dev->hw->has_mst_fifo) + val = I2C_MST_FIFO_CONTROL_RX_TRIG(dma_burst); + else + val = I2C_FIFO_CONTROL_RX_TRIG(dma_burst); + } else { + reg_offset = tegra_i2c_reg_addr(i2c_dev, I2C_TX_FIFO); + + slv_config.dst_addr = i2c_dev->base_phys + reg_offset; + slv_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + slv_config.dst_maxburst = dma_burst; + + if (i2c_dev->hw->has_mst_fifo) + val = I2C_MST_FIFO_CONTROL_TX_TRIG(dma_burst); + else + val = I2C_FIFO_CONTROL_TX_TRIG(dma_burst); + } + + slv_config.device_fc = true; + err = dmaengine_slave_config(i2c_dev->dma_chan, &slv_config); + if (err) { + dev_err(i2c_dev->dev, "DMA config failed: %d\n", err); + dev_err(i2c_dev->dev, "falling back to PIO\n"); + + tegra_i2c_release_dma(i2c_dev); + i2c_dev->dma_mode = false; + } else { + goto out; + } + } + + if (i2c_dev->hw->has_mst_fifo) + val = I2C_MST_FIFO_CONTROL_TX_TRIG(8) | + I2C_MST_FIFO_CONTROL_RX_TRIG(1); + else + val = I2C_FIFO_CONTROL_TX_TRIG(8) | + I2C_FIFO_CONTROL_RX_TRIG(1); +out: + i2c_writel(i2c_dev, val, reg); +} + +static unsigned long tegra_i2c_poll_completion(struct tegra_i2c_dev *i2c_dev, + struct completion *complete, + unsigned int timeout_ms) +{ + ktime_t ktime = ktime_get(); + ktime_t ktimeout = ktime_add_ms(ktime, timeout_ms); + + do { + u32 status = i2c_readl(i2c_dev, I2C_INT_STATUS); + + if (status) + tegra_i2c_isr(i2c_dev->irq, i2c_dev); + + if (completion_done(complete)) { + s64 delta = ktime_ms_delta(ktimeout, ktime); + + return msecs_to_jiffies(delta) ?: 1; + } + + ktime = ktime_get(); + + } while (ktime_before(ktime, ktimeout)); + + return 0; +} + +static unsigned long tegra_i2c_wait_completion(struct tegra_i2c_dev *i2c_dev, + struct completion *complete, + unsigned int timeout_ms) +{ + unsigned long ret; + + if (i2c_dev->atomic_mode) { + ret = tegra_i2c_poll_completion(i2c_dev, complete, timeout_ms); + } else { + enable_irq(i2c_dev->irq); + ret = wait_for_completion_timeout(complete, + msecs_to_jiffies(timeout_ms)); + disable_irq(i2c_dev->irq); + + /* + * Under some rare circumstances (like running KASAN + + * NFS root) CPU, which handles interrupt, may stuck in + * uninterruptible state for a significant time. In this + * case we will get timeout if I2C transfer is running on + * a sibling CPU, despite of IRQ being raised. + * + * In order to handle this rare condition, the IRQ status + * needs to be checked after timeout. + */ + if (ret == 0) + ret = tegra_i2c_poll_completion(i2c_dev, complete, 0); + } + + return ret; +} + +static int tegra_i2c_issue_bus_clear(struct i2c_adapter *adap) +{ + struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + u32 val, time_left; + int err; + + reinit_completion(&i2c_dev->msg_complete); + + val = FIELD_PREP(I2C_BC_SCLK_THRESHOLD, 9) | I2C_BC_STOP_COND | + I2C_BC_TERMINATE; + i2c_writel(i2c_dev, val, I2C_BUS_CLEAR_CNFG); + + err = tegra_i2c_wait_for_config_load(i2c_dev); + if (err) + return err; + + val |= I2C_BC_ENABLE; + i2c_writel(i2c_dev, val, I2C_BUS_CLEAR_CNFG); + tegra_i2c_unmask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); + + time_left = tegra_i2c_wait_completion(i2c_dev, &i2c_dev->msg_complete, 50); + tegra_i2c_mask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE); + + if (time_left == 0) { + dev_err(i2c_dev->dev, "failed to clear bus\n"); + return -ETIMEDOUT; + } + + val = i2c_readl(i2c_dev, I2C_BUS_CLEAR_STATUS); + if (!(val & I2C_BC_STATUS)) { + dev_err(i2c_dev->dev, "un-recovered arbitration lost\n"); + return -EIO; + } + + return -EAGAIN; +} + +static void tegra_i2c_push_packet_header(struct tegra_i2c_dev *i2c_dev, + struct i2c_msg *msg, + enum msg_end_type end_state) +{ + u32 *dma_buf = i2c_dev->dma_buf; + u32 packet_header; + + packet_header = FIELD_PREP(PACKET_HEADER0_HEADER_SIZE, 0) | + FIELD_PREP(PACKET_HEADER0_PROTOCOL, + PACKET_HEADER0_PROTOCOL_I2C) | + FIELD_PREP(PACKET_HEADER0_CONT_ID, i2c_dev->cont_id) | + FIELD_PREP(PACKET_HEADER0_PACKET_ID, 1); + + if (i2c_dev->dma_mode && !i2c_dev->msg_read) + *dma_buf++ = packet_header; + else + i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); + + packet_header = i2c_dev->msg_len - 1; + + if (i2c_dev->dma_mode && !i2c_dev->msg_read) + *dma_buf++ = packet_header; + else + i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); + + packet_header = I2C_HEADER_IE_ENABLE; + + if (end_state == MSG_END_CONTINUE) + packet_header |= I2C_HEADER_CONTINUE_XFER; + else if (end_state == MSG_END_REPEAT_START) + packet_header |= I2C_HEADER_REPEAT_START; + + if (msg->flags & I2C_M_TEN) { + packet_header |= msg->addr; + packet_header |= I2C_HEADER_10BIT_ADDR; + } else { + packet_header |= msg->addr << I2C_HEADER_SLAVE_ADDR_SHIFT; + } + + if (msg->flags & I2C_M_IGNORE_NAK) + packet_header |= I2C_HEADER_CONT_ON_NAK; + + if (msg->flags & I2C_M_RD) + packet_header |= I2C_HEADER_READ; + + if (i2c_dev->dma_mode && !i2c_dev->msg_read) + *dma_buf++ = packet_header; + else + i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); +} + +static int tegra_i2c_error_recover(struct tegra_i2c_dev *i2c_dev, + struct i2c_msg *msg) +{ + if (i2c_dev->msg_err == I2C_ERR_NONE) + return 0; + + tegra_i2c_init(i2c_dev); + + /* start recovery upon arbitration loss in single master mode */ + if (i2c_dev->msg_err == I2C_ERR_ARBITRATION_LOST) { + if (!i2c_dev->multimaster_mode) + return i2c_recover_bus(&i2c_dev->adapter); + + return -EAGAIN; + } + + if (i2c_dev->msg_err == I2C_ERR_NO_ACK) { + if (msg->flags & I2C_M_IGNORE_NAK) + return 0; + + return -EREMOTEIO; + } + + return -EIO; +} + +static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, + struct i2c_msg *msg, + enum msg_end_type end_state) +{ + unsigned long time_left, xfer_time = 100; + size_t xfer_size; + u32 int_mask; + int err; + + err = tegra_i2c_flush_fifos(i2c_dev); + if (err) + return err; + + i2c_dev->msg_buf = msg->buf; + i2c_dev->msg_len = msg->len; + + i2c_dev->msg_err = I2C_ERR_NONE; + i2c_dev->msg_read = !!(msg->flags & I2C_M_RD); + reinit_completion(&i2c_dev->msg_complete); + + /* + * For SMBUS block read command, read only 1 byte in the first transfer. + * Adjust that 1 byte for the next transfer in the msg buffer and msg + * length. + */ + if (msg->flags & I2C_M_RECV_LEN) { + if (end_state == MSG_END_CONTINUE) { + i2c_dev->msg_len = 1; + } else { + i2c_dev->msg_buf += 1; + i2c_dev->msg_len -= 1; + } + } + + i2c_dev->msg_buf_remaining = i2c_dev->msg_len; + + if (i2c_dev->msg_read) + xfer_size = i2c_dev->msg_len; + else + xfer_size = i2c_dev->msg_len + I2C_PACKET_HEADER_SIZE; + + xfer_size = ALIGN(xfer_size, BYTES_PER_FIFO_WORD); + + i2c_dev->dma_mode = xfer_size > I2C_PIO_MODE_PREFERRED_LEN && + i2c_dev->dma_buf && !i2c_dev->atomic_mode; + + tegra_i2c_config_fifo_trig(i2c_dev, xfer_size); + + /* + * Transfer time in mSec = Total bits / transfer rate + * Total bits = 9 bits per byte (including ACK bit) + Start & stop bits + */ + xfer_time += DIV_ROUND_CLOSEST(((xfer_size * 9) + 2) * MSEC_PER_SEC, + i2c_dev->timings.bus_freq_hz); + + int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; + tegra_i2c_unmask_irq(i2c_dev, int_mask); + + if (i2c_dev->dma_mode) { + if (i2c_dev->msg_read) { + dma_sync_single_for_device(i2c_dev->dma_dev, + i2c_dev->dma_phys, + xfer_size, DMA_FROM_DEVICE); + + err = tegra_i2c_dma_submit(i2c_dev, xfer_size); + if (err) + return err; + } else { + dma_sync_single_for_cpu(i2c_dev->dma_dev, + i2c_dev->dma_phys, + xfer_size, DMA_TO_DEVICE); + } + } + + tegra_i2c_push_packet_header(i2c_dev, msg, end_state); + + if (!i2c_dev->msg_read) { + if (i2c_dev->dma_mode) { + memcpy(i2c_dev->dma_buf + I2C_PACKET_HEADER_SIZE, + msg->buf, i2c_dev->msg_len); + + dma_sync_single_for_device(i2c_dev->dma_dev, + i2c_dev->dma_phys, + xfer_size, DMA_TO_DEVICE); + + err = tegra_i2c_dma_submit(i2c_dev, xfer_size); + if (err) + return err; + } else { + tegra_i2c_fill_tx_fifo(i2c_dev); + } + } + + if (i2c_dev->hw->has_per_pkt_xfer_complete_irq) + int_mask |= I2C_INT_PACKET_XFER_COMPLETE; + + if (!i2c_dev->dma_mode) { + if (msg->flags & I2C_M_RD) + int_mask |= I2C_INT_RX_FIFO_DATA_REQ; + else if (i2c_dev->msg_buf_remaining) + int_mask |= I2C_INT_TX_FIFO_DATA_REQ; + } + + tegra_i2c_unmask_irq(i2c_dev, int_mask); + dev_dbg(i2c_dev->dev, "unmasked IRQ: %02x\n", + i2c_readl(i2c_dev, I2C_INT_MASK)); + + if (i2c_dev->dma_mode) { + time_left = tegra_i2c_wait_completion(i2c_dev, + &i2c_dev->dma_complete, + xfer_time); + + /* + * Synchronize DMA first, since dmaengine_terminate_sync() + * performs synchronization after the transfer's termination + * and we want to get a completion if transfer succeeded. + */ + dmaengine_synchronize(i2c_dev->dma_chan); + dmaengine_terminate_sync(i2c_dev->dma_chan); + + if (!time_left && !completion_done(&i2c_dev->dma_complete)) { + dev_err(i2c_dev->dev, "DMA transfer timed out\n"); + tegra_i2c_init(i2c_dev); + return -ETIMEDOUT; + } + + if (i2c_dev->msg_read && i2c_dev->msg_err == I2C_ERR_NONE) { + dma_sync_single_for_cpu(i2c_dev->dma_dev, + i2c_dev->dma_phys, + xfer_size, DMA_FROM_DEVICE); + + memcpy(i2c_dev->msg_buf, i2c_dev->dma_buf, i2c_dev->msg_len); + } + } + + time_left = tegra_i2c_wait_completion(i2c_dev, &i2c_dev->msg_complete, + xfer_time); + + tegra_i2c_mask_irq(i2c_dev, int_mask); + + if (time_left == 0) { + dev_err(i2c_dev->dev, "I2C transfer timed out\n"); + tegra_i2c_init(i2c_dev); + return -ETIMEDOUT; + } + + dev_dbg(i2c_dev->dev, "transfer complete: %lu %d %d\n", + time_left, completion_done(&i2c_dev->msg_complete), + i2c_dev->msg_err); + + i2c_dev->dma_mode = false; + + err = tegra_i2c_error_recover(i2c_dev, msg); + if (err) + return err; + + return 0; +} + +static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], + int num) +{ + struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + int i, ret; + + ret = pm_runtime_get_sync(i2c_dev->dev); + if (ret < 0) { + dev_err(i2c_dev->dev, "runtime resume failed %d\n", ret); + pm_runtime_put_noidle(i2c_dev->dev); + return ret; + } + + for (i = 0; i < num; i++) { + enum msg_end_type end_type = MSG_END_STOP; + + if (i < (num - 1)) { + /* check whether follow up message is coming */ + if (msgs[i + 1].flags & I2C_M_NOSTART) + end_type = MSG_END_CONTINUE; + else + end_type = MSG_END_REPEAT_START; + } + /* If M_RECV_LEN use ContinueXfer to read the first byte */ + if (msgs[i].flags & I2C_M_RECV_LEN) { + ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], MSG_END_CONTINUE); + if (ret) + break; + /* Set the msg length from first byte */ + msgs[i].len += msgs[i].buf[0]; + dev_dbg(i2c_dev->dev, "reading %d bytes\n", msgs[i].len); + } + ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], end_type); + if (ret) + break; + } + + pm_runtime_put(i2c_dev->dev); + + return ret ?: i; +} + +static int tegra_i2c_xfer_atomic(struct i2c_adapter *adap, + struct i2c_msg msgs[], int num) +{ + struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + int ret; + + i2c_dev->atomic_mode = true; + ret = tegra_i2c_xfer(adap, msgs, num); + i2c_dev->atomic_mode = false; + + return ret; +} + +static u32 tegra_i2c_func(struct i2c_adapter *adap) +{ + struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + u32 ret = I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | + I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING; + + if (i2c_dev->hw->has_continue_xfer_support) + ret |= I2C_FUNC_NOSTART | I2C_FUNC_SMBUS_READ_BLOCK_DATA; + + return ret; +} + +static const struct i2c_algorithm tegra_i2c_algo = { + .master_xfer = tegra_i2c_xfer, + .master_xfer_atomic = tegra_i2c_xfer_atomic, + .functionality = tegra_i2c_func, +}; + +/* payload size is only 12 bit */ +static const struct i2c_adapter_quirks tegra_i2c_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN, + .max_read_len = SZ_4K, + .max_write_len = SZ_4K - I2C_PACKET_HEADER_SIZE, +}; + +static const struct i2c_adapter_quirks tegra194_i2c_quirks = { + .flags = I2C_AQ_NO_ZERO_LEN, + .max_write_len = SZ_64K - I2C_PACKET_HEADER_SIZE, +}; + +static struct i2c_bus_recovery_info tegra_i2c_recovery_info = { + .recover_bus = tegra_i2c_issue_bus_clear, +}; + +static const struct tegra_i2c_hw_feature tegra20_i2c_hw = { + .has_continue_xfer_support = false, + .has_per_pkt_xfer_complete_irq = false, + .clk_divisor_hs_mode = 3, + .clk_divisor_std_mode = 0, + .clk_divisor_fast_mode = 0, + .clk_divisor_fast_plus_mode = 0, + .has_config_load_reg = false, + .has_multi_master_mode = false, + .has_slcg_override_reg = false, + .has_mst_fifo = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_fastplus_mode = 0x4, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_fast_plus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = false, +}; + +static const struct tegra_i2c_hw_feature tegra30_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = false, + .clk_divisor_hs_mode = 3, + .clk_divisor_std_mode = 0, + .clk_divisor_fast_mode = 0, + .clk_divisor_fast_plus_mode = 0, + .has_config_load_reg = false, + .has_multi_master_mode = false, + .has_slcg_override_reg = false, + .has_mst_fifo = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = false, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_fastplus_mode = 0x4, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_fast_plus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = false, +}; + +static const struct tegra_i2c_hw_feature tegra114_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = true, + .clk_divisor_hs_mode = 1, + .clk_divisor_std_mode = 0x19, + .clk_divisor_fast_mode = 0x19, + .clk_divisor_fast_plus_mode = 0x10, + .has_config_load_reg = false, + .has_multi_master_mode = false, + .has_slcg_override_reg = false, + .has_mst_fifo = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_fastplus_mode = 0x4, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_fast_plus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = false, +}; + +static const struct tegra_i2c_hw_feature tegra124_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = true, + .clk_divisor_hs_mode = 1, + .clk_divisor_std_mode = 0x19, + .clk_divisor_fast_mode = 0x19, + .clk_divisor_fast_plus_mode = 0x10, + .has_config_load_reg = true, + .has_multi_master_mode = false, + .has_slcg_override_reg = true, + .has_mst_fifo = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_fastplus_mode = 0x4, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x0, + .setup_hold_time_fast_fast_plus_mode = 0x0, + .setup_hold_time_hs_mode = 0x0, + .has_interface_timing_reg = true, +}; + +static const struct tegra_i2c_hw_feature tegra210_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = true, + .clk_divisor_hs_mode = 1, + .clk_divisor_std_mode = 0x19, + .clk_divisor_fast_mode = 0x19, + .clk_divisor_fast_plus_mode = 0x10, + .has_config_load_reg = true, + .has_multi_master_mode = false, + .has_slcg_override_reg = true, + .has_mst_fifo = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = true, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x2, + .tlow_fast_fastplus_mode = 0x4, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0, + .setup_hold_time_fast_fast_plus_mode = 0, + .setup_hold_time_hs_mode = 0, + .has_interface_timing_reg = true, +}; + +static const struct tegra_i2c_hw_feature tegra186_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = true, + .clk_divisor_hs_mode = 1, + .clk_divisor_std_mode = 0x16, + .clk_divisor_fast_mode = 0x19, + .clk_divisor_fast_plus_mode = 0x10, + .has_config_load_reg = true, + .has_multi_master_mode = false, + .has_slcg_override_reg = true, + .has_mst_fifo = false, + .quirks = &tegra_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = false, + .tlow_std_mode = 0x4, + .thigh_std_mode = 0x3, + .tlow_fast_fastplus_mode = 0x4, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0, + .setup_hold_time_fast_fast_plus_mode = 0, + .setup_hold_time_hs_mode = 0, + .has_interface_timing_reg = true, +}; + +static const struct tegra_i2c_hw_feature tegra194_i2c_hw = { + .has_continue_xfer_support = true, + .has_per_pkt_xfer_complete_irq = true, + .clk_divisor_hs_mode = 1, + .clk_divisor_std_mode = 0x4f, + .clk_divisor_fast_mode = 0x3c, + .clk_divisor_fast_plus_mode = 0x16, + .has_config_load_reg = true, + .has_multi_master_mode = true, + .has_slcg_override_reg = true, + .has_mst_fifo = true, + .quirks = &tegra194_i2c_quirks, + .supports_bus_clear = true, + .has_apb_dma = false, + .tlow_std_mode = 0x8, + .thigh_std_mode = 0x7, + .tlow_fast_fastplus_mode = 0x2, + .thigh_fast_fastplus_mode = 0x2, + .setup_hold_time_std_mode = 0x08080808, + .setup_hold_time_fast_fast_plus_mode = 0x02020202, + .setup_hold_time_hs_mode = 0x090909, + .has_interface_timing_reg = true, +}; + +static const struct of_device_id tegra_i2c_of_match[] = { + { .compatible = "nvidia,tegra194-i2c", .data = &tegra194_i2c_hw, }, + { .compatible = "nvidia,tegra186-i2c", .data = &tegra186_i2c_hw, }, +#if IS_ENABLED(CONFIG_ARCH_TEGRA_210_SOC) + { .compatible = "nvidia,tegra210-i2c-vi", .data = &tegra210_i2c_hw, }, +#endif + { .compatible = "nvidia,tegra210-i2c", .data = &tegra210_i2c_hw, }, + { .compatible = "nvidia,tegra124-i2c", .data = &tegra124_i2c_hw, }, + { .compatible = "nvidia,tegra114-i2c", .data = &tegra114_i2c_hw, }, + { .compatible = "nvidia,tegra30-i2c", .data = &tegra30_i2c_hw, }, + { .compatible = "nvidia,tegra20-i2c", .data = &tegra20_i2c_hw, }, +#if IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC) + { .compatible = "nvidia,tegra20-i2c-dvc", .data = &tegra20_i2c_hw, }, +#endif + {}, +}; +MODULE_DEVICE_TABLE(of, tegra_i2c_of_match); + +static void tegra_i2c_parse_dt(struct tegra_i2c_dev *i2c_dev) +{ + struct device_node *np = i2c_dev->dev->of_node; + bool multi_mode; + + i2c_parse_fw_timings(i2c_dev->dev, &i2c_dev->timings, true); + + multi_mode = device_property_read_bool(i2c_dev->dev, "multi-master"); + i2c_dev->multimaster_mode = multi_mode; + + if (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC) && + of_device_is_compatible(np, "nvidia,tegra20-i2c-dvc")) + i2c_dev->is_dvc = true; + + if (IS_ENABLED(CONFIG_ARCH_TEGRA_210_SOC) && + of_device_is_compatible(np, "nvidia,tegra210-i2c-vi")) + i2c_dev->is_vi = true; +} + +static int tegra_i2c_init_reset(struct tegra_i2c_dev *i2c_dev) +{ + if (ACPI_HANDLE(i2c_dev->dev)) + return 0; + + i2c_dev->rst = devm_reset_control_get_exclusive(i2c_dev->dev, "i2c"); + if (IS_ERR(i2c_dev->rst)) + return dev_err_probe(i2c_dev->dev, PTR_ERR(i2c_dev->rst), + "failed to get reset control\n"); + + return 0; +} + +static int tegra_i2c_init_clocks(struct tegra_i2c_dev *i2c_dev) +{ + int err; + + if (ACPI_HANDLE(i2c_dev->dev)) + return 0; + + i2c_dev->clocks[i2c_dev->nclocks++].id = "div-clk"; + + if (i2c_dev->hw == &tegra20_i2c_hw || i2c_dev->hw == &tegra30_i2c_hw) + i2c_dev->clocks[i2c_dev->nclocks++].id = "fast-clk"; + + if (IS_VI(i2c_dev)) + i2c_dev->clocks[i2c_dev->nclocks++].id = "slow"; + + err = devm_clk_bulk_get(i2c_dev->dev, i2c_dev->nclocks, + i2c_dev->clocks); + if (err) + return err; + + err = clk_bulk_prepare(i2c_dev->nclocks, i2c_dev->clocks); + if (err) + return err; + + i2c_dev->div_clk = i2c_dev->clocks[0].clk; + + if (!i2c_dev->multimaster_mode) + return 0; + + err = clk_enable(i2c_dev->div_clk); + if (err) { + dev_err(i2c_dev->dev, "failed to enable div-clk: %d\n", err); + goto unprepare_clocks; + } + + return 0; + +unprepare_clocks: + clk_bulk_unprepare(i2c_dev->nclocks, i2c_dev->clocks); + + return err; +} + +static void tegra_i2c_release_clocks(struct tegra_i2c_dev *i2c_dev) +{ + if (i2c_dev->multimaster_mode) + clk_disable(i2c_dev->div_clk); + + clk_bulk_unprepare(i2c_dev->nclocks, i2c_dev->clocks); +} + +static int tegra_i2c_init_hardware(struct tegra_i2c_dev *i2c_dev) +{ + int ret; + + ret = pm_runtime_get_sync(i2c_dev->dev); + if (ret < 0) + dev_err(i2c_dev->dev, "runtime resume failed: %d\n", ret); + else + ret = tegra_i2c_init(i2c_dev); + + pm_runtime_put_sync(i2c_dev->dev); + + return ret; +} + +static int tegra_i2c_probe(struct platform_device *pdev) +{ + struct tegra_i2c_dev *i2c_dev; + struct resource *res; + int err; + + i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); + if (!i2c_dev) + return -ENOMEM; + + platform_set_drvdata(pdev, i2c_dev); + + init_completion(&i2c_dev->msg_complete); + init_completion(&i2c_dev->dma_complete); + + i2c_dev->hw = device_get_match_data(&pdev->dev); + i2c_dev->cont_id = pdev->id; + i2c_dev->dev = &pdev->dev; + + i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(i2c_dev->base)) + return PTR_ERR(i2c_dev->base); + + i2c_dev->base_phys = res->start; + + err = platform_get_irq(pdev, 0); + if (err < 0) + return err; + + i2c_dev->irq = err; + + /* interrupt will be enabled during of transfer time */ + irq_set_status_flags(i2c_dev->irq, IRQ_NOAUTOEN); + + err = devm_request_threaded_irq(i2c_dev->dev, i2c_dev->irq, + NULL, tegra_i2c_isr, + IRQF_NO_SUSPEND | IRQF_ONESHOT, + dev_name(i2c_dev->dev), i2c_dev); + if (err) + return err; + + tegra_i2c_parse_dt(i2c_dev); + + err = tegra_i2c_init_reset(i2c_dev); + if (err) + return err; + + err = tegra_i2c_init_clocks(i2c_dev); + if (err) + return err; + + err = tegra_i2c_init_dma(i2c_dev); + if (err) + goto release_clocks; + + /* + * VI I2C is in VE power domain which is not always ON and not + * IRQ-safe. Thus, IRQ-safe device shouldn't be attached to a + * non IRQ-safe domain because this prevents powering off the power + * domain. + * + * VI I2C device shouldn't be marked as IRQ-safe because VI I2C won't + * be used for atomic transfers. + */ + if (!IS_VI(i2c_dev)) + pm_runtime_irq_safe(i2c_dev->dev); + + pm_runtime_enable(i2c_dev->dev); + + err = tegra_i2c_init_hardware(i2c_dev); + if (err) + goto release_rpm; + + i2c_set_adapdata(&i2c_dev->adapter, i2c_dev); + i2c_dev->adapter.dev.of_node = i2c_dev->dev->of_node; + i2c_dev->adapter.dev.parent = i2c_dev->dev; + i2c_dev->adapter.retries = 1; + i2c_dev->adapter.timeout = 6 * HZ; + i2c_dev->adapter.quirks = i2c_dev->hw->quirks; + i2c_dev->adapter.owner = THIS_MODULE; + i2c_dev->adapter.class = I2C_CLASS_DEPRECATED; + i2c_dev->adapter.algo = &tegra_i2c_algo; + i2c_dev->adapter.nr = pdev->id; + ACPI_COMPANION_SET(&i2c_dev->adapter.dev, ACPI_COMPANION(&pdev->dev)); + + if (i2c_dev->hw->supports_bus_clear) + i2c_dev->adapter.bus_recovery_info = &tegra_i2c_recovery_info; + + strscpy(i2c_dev->adapter.name, dev_name(i2c_dev->dev), + sizeof(i2c_dev->adapter.name)); + + err = i2c_add_numbered_adapter(&i2c_dev->adapter); + if (err) + goto release_rpm; + + return 0; + +release_rpm: + pm_runtime_disable(i2c_dev->dev); + + tegra_i2c_release_dma(i2c_dev); +release_clocks: + tegra_i2c_release_clocks(i2c_dev); + + return err; +} + +static void tegra_i2c_remove(struct platform_device *pdev) +{ + struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c_dev->adapter); + pm_runtime_force_suspend(i2c_dev->dev); + + tegra_i2c_release_dma(i2c_dev); + tegra_i2c_release_clocks(i2c_dev); +} + +static int __maybe_unused tegra_i2c_runtime_resume(struct device *dev) +{ + struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int err; + + err = pinctrl_pm_select_default_state(dev); + if (err) + return err; + + err = clk_bulk_enable(i2c_dev->nclocks, i2c_dev->clocks); + if (err) + return err; + + /* + * VI I2C device is attached to VE power domain which goes through + * power ON/OFF during runtime PM resume/suspend, meaning that + * controller needs to be re-initialized after power ON. + */ + if (IS_VI(i2c_dev)) { + err = tegra_i2c_init(i2c_dev); + if (err) + goto disable_clocks; + } + + return 0; + +disable_clocks: + clk_bulk_disable(i2c_dev->nclocks, i2c_dev->clocks); + + return err; +} + +static int __maybe_unused tegra_i2c_runtime_suspend(struct device *dev) +{ + struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + + clk_bulk_disable(i2c_dev->nclocks, i2c_dev->clocks); + + return pinctrl_pm_select_idle_state(dev); +} + +static int __maybe_unused tegra_i2c_suspend(struct device *dev) +{ + struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int err; + + i2c_mark_adapter_suspended(&i2c_dev->adapter); + + if (!pm_runtime_status_suspended(dev)) { + err = tegra_i2c_runtime_suspend(dev); + if (err) + return err; + } + + return 0; +} + +static int __maybe_unused tegra_i2c_resume(struct device *dev) +{ + struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int err; + + /* + * We need to ensure that clocks are enabled so that registers can be + * restored in tegra_i2c_init(). + */ + err = tegra_i2c_runtime_resume(dev); + if (err) + return err; + + err = tegra_i2c_init(i2c_dev); + if (err) + return err; + + /* + * In case we are runtime suspended, disable clocks again so that we + * don't unbalance the clock reference counts during the next runtime + * resume transition. + */ + if (pm_runtime_status_suspended(dev)) { + err = tegra_i2c_runtime_suspend(dev); + if (err) + return err; + } + + i2c_mark_adapter_resumed(&i2c_dev->adapter); + + return 0; +} + +static const struct dev_pm_ops tegra_i2c_pm = { + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(tegra_i2c_suspend, tegra_i2c_resume) + SET_RUNTIME_PM_OPS(tegra_i2c_runtime_suspend, tegra_i2c_runtime_resume, + NULL) +}; + +static const struct acpi_device_id tegra_i2c_acpi_match[] = { + {.id = "NVDA0101", .driver_data = (kernel_ulong_t)&tegra210_i2c_hw}, + {.id = "NVDA0201", .driver_data = (kernel_ulong_t)&tegra186_i2c_hw}, + {.id = "NVDA0301", .driver_data = (kernel_ulong_t)&tegra194_i2c_hw}, + { } +}; +MODULE_DEVICE_TABLE(acpi, tegra_i2c_acpi_match); + +static struct platform_driver tegra_i2c_driver = { + .probe = tegra_i2c_probe, + .remove_new = tegra_i2c_remove, + .driver = { + .name = "tegra-i2c", + .of_match_table = tegra_i2c_of_match, + .acpi_match_table = tegra_i2c_acpi_match, + .pm = &tegra_i2c_pm, + }, +}; +module_platform_driver(tegra_i2c_driver); + +MODULE_DESCRIPTION("NVIDIA Tegra I2C Bus Controller driver"); +MODULE_AUTHOR("Colin Cross"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-thunderx-pcidrv.c b/drivers/i2c/busses/i2c-thunderx-pcidrv.c new file mode 100644 index 000000000..a77cd86fe --- /dev/null +++ b/drivers/i2c/busses/i2c-thunderx-pcidrv.c @@ -0,0 +1,265 @@ +/* + * Cavium ThunderX i2c driver. + * + * Copyright (C) 2015,2016 Cavium Inc. + * Authors: Fred Martin <fmartin@caviumnetworks.com> + * Jan Glauber <jglauber@cavium.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/acpi.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/i2c-smbus.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_irq.h> +#include <linux/pci.h> + +#include "i2c-octeon-core.h" + +#define DRV_NAME "i2c-thunderx" + +#define PCI_DEVICE_ID_THUNDER_TWSI 0xa012 + +#define SYS_FREQ_DEFAULT 700000000 + +#define TWSI_INT_ENA_W1C 0x1028 +#define TWSI_INT_ENA_W1S 0x1030 + +/* + * Enable the CORE interrupt. + * The interrupt will be asserted when there is non-STAT_IDLE state in the + * SW_TWSI_EOP_TWSI_STAT register. + */ +static void thunder_i2c_int_enable(struct octeon_i2c *i2c) +{ + octeon_i2c_writeq_flush(TWSI_INT_CORE_INT, + i2c->twsi_base + TWSI_INT_ENA_W1S); +} + +/* + * Disable the CORE interrupt. + */ +static void thunder_i2c_int_disable(struct octeon_i2c *i2c) +{ + octeon_i2c_writeq_flush(TWSI_INT_CORE_INT, + i2c->twsi_base + TWSI_INT_ENA_W1C); +} + +static void thunder_i2c_hlc_int_enable(struct octeon_i2c *i2c) +{ + octeon_i2c_writeq_flush(TWSI_INT_ST_INT | TWSI_INT_TS_INT, + i2c->twsi_base + TWSI_INT_ENA_W1S); +} + +static void thunder_i2c_hlc_int_disable(struct octeon_i2c *i2c) +{ + octeon_i2c_writeq_flush(TWSI_INT_ST_INT | TWSI_INT_TS_INT, + i2c->twsi_base + TWSI_INT_ENA_W1C); +} + +static u32 thunderx_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | + I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_SMBUS_BLOCK_PROC_CALL; +} + +static const struct i2c_algorithm thunderx_i2c_algo = { + .master_xfer = octeon_i2c_xfer, + .functionality = thunderx_i2c_functionality, +}; + +static const struct i2c_adapter thunderx_i2c_ops = { + .owner = THIS_MODULE, + .name = "ThunderX adapter", + .algo = &thunderx_i2c_algo, +}; + +static void thunder_i2c_clock_enable(struct device *dev, struct octeon_i2c *i2c) +{ + int ret; + + if (acpi_disabled) { + /* DT */ + i2c->clk = clk_get(dev, NULL); + if (IS_ERR(i2c->clk)) { + i2c->clk = NULL; + goto skip; + } + + ret = clk_prepare_enable(i2c->clk); + if (ret) + goto skip; + i2c->sys_freq = clk_get_rate(i2c->clk); + } else { + /* ACPI */ + device_property_read_u32(dev, "sclk", &i2c->sys_freq); + } + +skip: + if (!i2c->sys_freq) + i2c->sys_freq = SYS_FREQ_DEFAULT; +} + +static void thunder_i2c_clock_disable(struct device *dev, struct clk *clk) +{ + if (!clk) + return; + clk_disable_unprepare(clk); + clk_put(clk); +} + +static int thunder_i2c_smbus_setup_of(struct octeon_i2c *i2c, + struct device_node *node) +{ + struct i2c_client *ara; + + if (!node) + return -EINVAL; + + i2c->alert_data.irq = irq_of_parse_and_map(node, 0); + if (!i2c->alert_data.irq) + return -EINVAL; + + ara = i2c_new_smbus_alert_device(&i2c->adap, &i2c->alert_data); + if (IS_ERR(ara)) + return PTR_ERR(ara); + + i2c->ara = ara; + + return 0; +} + +static int thunder_i2c_smbus_setup(struct octeon_i2c *i2c, + struct device_node *node) +{ + /* TODO: ACPI support */ + if (!acpi_disabled) + return -EOPNOTSUPP; + + return thunder_i2c_smbus_setup_of(i2c, node); +} + +static void thunder_i2c_smbus_remove(struct octeon_i2c *i2c) +{ + i2c_unregister_device(i2c->ara); +} + +static int thunder_i2c_probe_pci(struct pci_dev *pdev, + const struct pci_device_id *ent) +{ + struct device *dev = &pdev->dev; + struct octeon_i2c *i2c; + int ret; + + i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->roff.sw_twsi = 0x1000; + i2c->roff.twsi_int = 0x1010; + i2c->roff.sw_twsi_ext = 0x1018; + + i2c->dev = dev; + pci_set_drvdata(pdev, i2c); + ret = pcim_enable_device(pdev); + if (ret) + return ret; + + ret = pci_request_regions(pdev, DRV_NAME); + if (ret) + return ret; + + i2c->twsi_base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0)); + if (!i2c->twsi_base) + return -EINVAL; + + thunder_i2c_clock_enable(dev, i2c); + ret = device_property_read_u32(dev, "clock-frequency", &i2c->twsi_freq); + if (ret) + i2c->twsi_freq = I2C_MAX_STANDARD_MODE_FREQ; + + init_waitqueue_head(&i2c->queue); + + i2c->int_enable = thunder_i2c_int_enable; + i2c->int_disable = thunder_i2c_int_disable; + i2c->hlc_int_enable = thunder_i2c_hlc_int_enable; + i2c->hlc_int_disable = thunder_i2c_hlc_int_disable; + + ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSIX); + if (ret < 0) + goto error; + + ret = devm_request_irq(dev, pci_irq_vector(pdev, 0), octeon_i2c_isr, 0, + DRV_NAME, i2c); + if (ret) + goto error; + + ret = octeon_i2c_init_lowlevel(i2c); + if (ret) + goto error; + + octeon_i2c_set_clock(i2c); + + i2c->adap = thunderx_i2c_ops; + i2c->adap.retries = 5; + i2c->adap.class = I2C_CLASS_HWMON; + i2c->adap.bus_recovery_info = &octeon_i2c_recovery_info; + i2c->adap.dev.parent = dev; + i2c->adap.dev.of_node = pdev->dev.of_node; + i2c->adap.dev.fwnode = dev->fwnode; + snprintf(i2c->adap.name, sizeof(i2c->adap.name), + "Cavium ThunderX i2c adapter at %s", dev_name(dev)); + i2c_set_adapdata(&i2c->adap, i2c); + + ret = i2c_add_adapter(&i2c->adap); + if (ret) + goto error; + + dev_info(i2c->dev, "Probed. Set system clock to %u\n", i2c->sys_freq); + + ret = thunder_i2c_smbus_setup(i2c, pdev->dev.of_node); + if (ret) + dev_info(dev, "SMBUS alert not active on this bus\n"); + + return 0; + +error: + thunder_i2c_clock_disable(dev, i2c->clk); + return ret; +} + +static void thunder_i2c_remove_pci(struct pci_dev *pdev) +{ + struct octeon_i2c *i2c = pci_get_drvdata(pdev); + + thunder_i2c_smbus_remove(i2c); + thunder_i2c_clock_disable(&pdev->dev, i2c->clk); + i2c_del_adapter(&i2c->adap); +} + +static const struct pci_device_id thunder_i2c_pci_id_table[] = { + { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, PCI_DEVICE_ID_THUNDER_TWSI) }, + { 0, } +}; + +MODULE_DEVICE_TABLE(pci, thunder_i2c_pci_id_table); + +static struct pci_driver thunder_i2c_pci_driver = { + .name = DRV_NAME, + .id_table = thunder_i2c_pci_id_table, + .probe = thunder_i2c_probe_pci, + .remove = thunder_i2c_remove_pci, +}; + +module_pci_driver(thunder_i2c_pci_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Fred Martin <fmartin@caviumnetworks.com>"); +MODULE_DESCRIPTION("I2C-Bus adapter for Cavium ThunderX SOC"); diff --git a/drivers/i2c/busses/i2c-tiny-usb.c b/drivers/i2c/busses/i2c-tiny-usb.c new file mode 100644 index 000000000..1bffe36c4 --- /dev/null +++ b/drivers/i2c/busses/i2c-tiny-usb.c @@ -0,0 +1,305 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * driver for the i2c-tiny-usb adapter - 1.0 + * http://www.harbaum.org/till/i2c_tiny_usb + * + * Copyright (C) 2006-2007 Till Harbaum (Till@Harbaum.org) + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/types.h> + +/* include interfaces to usb layer */ +#include <linux/usb.h> + +/* include interface to i2c layer */ +#include <linux/i2c.h> + +/* commands via USB, must match command ids in the firmware */ +#define CMD_ECHO 0 +#define CMD_GET_FUNC 1 +#define CMD_SET_DELAY 2 +#define CMD_GET_STATUS 3 + +#define CMD_I2C_IO 4 +#define CMD_I2C_IO_BEGIN (1<<0) +#define CMD_I2C_IO_END (1<<1) + +/* i2c bit delay, default is 10us -> 100kHz max + (in practice, due to additional delays in the i2c bitbanging + code this results in a i2c clock of about 50kHz) */ +static unsigned short delay = 10; +module_param(delay, ushort, 0); +MODULE_PARM_DESC(delay, "bit delay in microseconds " + "(default is 10us for 100kHz max)"); + +static int usb_read(struct i2c_adapter *adapter, int cmd, + int value, int index, void *data, int len); + +static int usb_write(struct i2c_adapter *adapter, int cmd, + int value, int index, void *data, int len); + +/* ----- begin of i2c layer ---------------------------------------------- */ + +#define STATUS_IDLE 0 +#define STATUS_ADDRESS_ACK 1 +#define STATUS_ADDRESS_NAK 2 + +static int usb_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) +{ + unsigned char *pstatus; + struct i2c_msg *pmsg; + int i, ret; + + dev_dbg(&adapter->dev, "master xfer %d messages:\n", num); + + pstatus = kmalloc(sizeof(*pstatus), GFP_KERNEL); + if (!pstatus) + return -ENOMEM; + + for (i = 0 ; i < num ; i++) { + int cmd = CMD_I2C_IO; + + if (i == 0) + cmd |= CMD_I2C_IO_BEGIN; + + if (i == num-1) + cmd |= CMD_I2C_IO_END; + + pmsg = &msgs[i]; + + dev_dbg(&adapter->dev, + " %d: %s (flags %d) %d bytes to 0x%02x\n", + i, pmsg->flags & I2C_M_RD ? "read" : "write", + pmsg->flags, pmsg->len, pmsg->addr); + + /* and directly send the message */ + if (pmsg->flags & I2C_M_RD) { + /* read data */ + if (usb_read(adapter, cmd, + pmsg->flags, pmsg->addr, + pmsg->buf, pmsg->len) != pmsg->len) { + dev_err(&adapter->dev, + "failure reading data\n"); + ret = -EIO; + goto out; + } + } else { + /* write data */ + if (usb_write(adapter, cmd, + pmsg->flags, pmsg->addr, + pmsg->buf, pmsg->len) != pmsg->len) { + dev_err(&adapter->dev, + "failure writing data\n"); + ret = -EIO; + goto out; + } + } + + /* read status */ + if (usb_read(adapter, CMD_GET_STATUS, 0, 0, pstatus, 1) != 1) { + dev_err(&adapter->dev, "failure reading status\n"); + ret = -EIO; + goto out; + } + + dev_dbg(&adapter->dev, " status = %d\n", *pstatus); + if (*pstatus == STATUS_ADDRESS_NAK) { + ret = -ENXIO; + goto out; + } + } + + ret = i; +out: + kfree(pstatus); + return ret; +} + +static u32 usb_func(struct i2c_adapter *adapter) +{ + __le32 *pfunc; + u32 ret; + + pfunc = kmalloc(sizeof(*pfunc), GFP_KERNEL); + + /* get functionality from adapter */ + if (!pfunc || usb_read(adapter, CMD_GET_FUNC, 0, 0, pfunc, + sizeof(*pfunc)) != sizeof(*pfunc)) { + dev_err(&adapter->dev, "failure reading functionality\n"); + ret = 0; + goto out; + } + + ret = le32_to_cpup(pfunc); +out: + kfree(pfunc); + return ret; +} + +/* This is the actual algorithm we define */ +static const struct i2c_algorithm usb_algorithm = { + .master_xfer = usb_xfer, + .functionality = usb_func, +}; + +/* ----- end of i2c layer ------------------------------------------------ */ + +/* ----- begin of usb layer ---------------------------------------------- */ + +/* + * Initially the usb i2c interface uses a vid/pid pair donated by + * Future Technology Devices International Ltd., later a pair was + * bought from EZPrototypes + */ +static const struct usb_device_id i2c_tiny_usb_table[] = { + { USB_DEVICE(0x0403, 0xc631) }, /* FTDI */ + { USB_DEVICE(0x1c40, 0x0534) }, /* EZPrototypes */ + { } /* Terminating entry */ +}; + +MODULE_DEVICE_TABLE(usb, i2c_tiny_usb_table); + +/* Structure to hold all of our device specific stuff */ +struct i2c_tiny_usb { + struct usb_device *usb_dev; /* the usb device for this device */ + struct usb_interface *interface; /* the interface for this device */ + struct i2c_adapter adapter; /* i2c related things */ +}; + +static int usb_read(struct i2c_adapter *adapter, int cmd, + int value, int index, void *data, int len) +{ + struct i2c_tiny_usb *dev = (struct i2c_tiny_usb *)adapter->algo_data; + void *dmadata = kmalloc(len, GFP_KERNEL); + int ret; + + if (!dmadata) + return -ENOMEM; + + /* do control transfer */ + ret = usb_control_msg(dev->usb_dev, usb_rcvctrlpipe(dev->usb_dev, 0), + cmd, USB_TYPE_VENDOR | USB_RECIP_INTERFACE | + USB_DIR_IN, value, index, dmadata, len, 2000); + + memcpy(data, dmadata, len); + kfree(dmadata); + return ret; +} + +static int usb_write(struct i2c_adapter *adapter, int cmd, + int value, int index, void *data, int len) +{ + struct i2c_tiny_usb *dev = (struct i2c_tiny_usb *)adapter->algo_data; + void *dmadata = kmemdup(data, len, GFP_KERNEL); + int ret; + + if (!dmadata) + return -ENOMEM; + + /* do control transfer */ + ret = usb_control_msg(dev->usb_dev, usb_sndctrlpipe(dev->usb_dev, 0), + cmd, USB_TYPE_VENDOR | USB_RECIP_INTERFACE, + value, index, dmadata, len, 2000); + + kfree(dmadata); + return ret; +} + +static void i2c_tiny_usb_free(struct i2c_tiny_usb *dev) +{ + usb_put_dev(dev->usb_dev); + kfree(dev); +} + +static int i2c_tiny_usb_probe(struct usb_interface *interface, + const struct usb_device_id *id) +{ + struct i2c_tiny_usb *dev; + int retval = -ENOMEM; + u16 version; + + if (interface->intf_assoc && + interface->intf_assoc->bFunctionClass != USB_CLASS_VENDOR_SPEC) + return -ENODEV; + + dev_dbg(&interface->dev, "probing usb device\n"); + + /* allocate memory for our device state and initialize it */ + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) + goto error; + + dev->usb_dev = usb_get_dev(interface_to_usbdev(interface)); + dev->interface = interface; + + /* save our data pointer in this interface device */ + usb_set_intfdata(interface, dev); + + version = le16_to_cpu(dev->usb_dev->descriptor.bcdDevice); + dev_info(&interface->dev, + "version %x.%02x found at bus %03d address %03d\n", + version >> 8, version & 0xff, + dev->usb_dev->bus->busnum, dev->usb_dev->devnum); + + /* setup i2c adapter description */ + dev->adapter.owner = THIS_MODULE; + dev->adapter.class = I2C_CLASS_HWMON; + dev->adapter.algo = &usb_algorithm; + dev->adapter.algo_data = dev; + snprintf(dev->adapter.name, sizeof(dev->adapter.name), + "i2c-tiny-usb at bus %03d device %03d", + dev->usb_dev->bus->busnum, dev->usb_dev->devnum); + + if (usb_write(&dev->adapter, CMD_SET_DELAY, delay, 0, NULL, 0) != 0) { + dev_err(&dev->adapter.dev, + "failure setting delay to %dus\n", delay); + retval = -EIO; + goto error; + } + + dev->adapter.dev.parent = &dev->interface->dev; + + /* and finally attach to i2c layer */ + i2c_add_adapter(&dev->adapter); + + /* inform user about successful attachment to i2c layer */ + dev_info(&dev->adapter.dev, "connected i2c-tiny-usb device\n"); + + return 0; + + error: + if (dev) + i2c_tiny_usb_free(dev); + + return retval; +} + +static void i2c_tiny_usb_disconnect(struct usb_interface *interface) +{ + struct i2c_tiny_usb *dev = usb_get_intfdata(interface); + + i2c_del_adapter(&dev->adapter); + usb_set_intfdata(interface, NULL); + i2c_tiny_usb_free(dev); + + dev_dbg(&interface->dev, "disconnected\n"); +} + +static struct usb_driver i2c_tiny_usb_driver = { + .name = "i2c-tiny-usb", + .probe = i2c_tiny_usb_probe, + .disconnect = i2c_tiny_usb_disconnect, + .id_table = i2c_tiny_usb_table, +}; + +module_usb_driver(i2c_tiny_usb_driver); + +/* ----- end of usb layer ------------------------------------------------ */ + +MODULE_AUTHOR("Till Harbaum <Till@Harbaum.org>"); +MODULE_DESCRIPTION("i2c-tiny-usb driver v1.0"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-uniphier-f.c b/drivers/i2c/busses/i2c-uniphier-f.c new file mode 100644 index 000000000..dbc91c7c3 --- /dev/null +++ b/drivers/i2c/busses/i2c-uniphier-f.c @@ -0,0 +1,632 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com> + */ + +#include <linux/clk.h> +#include <linux/i2c.h> +#include <linux/iopoll.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +#define UNIPHIER_FI2C_CR 0x00 /* control register */ +#define UNIPHIER_FI2C_CR_MST BIT(3) /* master mode */ +#define UNIPHIER_FI2C_CR_STA BIT(2) /* start condition */ +#define UNIPHIER_FI2C_CR_STO BIT(1) /* stop condition */ +#define UNIPHIER_FI2C_CR_NACK BIT(0) /* do not return ACK */ +#define UNIPHIER_FI2C_DTTX 0x04 /* TX FIFO */ +#define UNIPHIER_FI2C_DTTX_CMD BIT(8) /* send command (slave addr) */ +#define UNIPHIER_FI2C_DTTX_RD BIT(0) /* read transaction */ +#define UNIPHIER_FI2C_DTRX 0x04 /* RX FIFO */ +#define UNIPHIER_FI2C_SLAD 0x0c /* slave address */ +#define UNIPHIER_FI2C_CYC 0x10 /* clock cycle control */ +#define UNIPHIER_FI2C_LCTL 0x14 /* clock low period control */ +#define UNIPHIER_FI2C_SSUT 0x18 /* restart/stop setup time control */ +#define UNIPHIER_FI2C_DSUT 0x1c /* data setup time control */ +#define UNIPHIER_FI2C_INT 0x20 /* interrupt status */ +#define UNIPHIER_FI2C_IE 0x24 /* interrupt enable */ +#define UNIPHIER_FI2C_IC 0x28 /* interrupt clear */ +#define UNIPHIER_FI2C_INT_TE BIT(9) /* TX FIFO empty */ +#define UNIPHIER_FI2C_INT_RF BIT(8) /* RX FIFO full */ +#define UNIPHIER_FI2C_INT_TC BIT(7) /* send complete (STOP) */ +#define UNIPHIER_FI2C_INT_RC BIT(6) /* receive complete (STOP) */ +#define UNIPHIER_FI2C_INT_TB BIT(5) /* sent specified bytes */ +#define UNIPHIER_FI2C_INT_RB BIT(4) /* received specified bytes */ +#define UNIPHIER_FI2C_INT_NA BIT(2) /* no ACK */ +#define UNIPHIER_FI2C_INT_AL BIT(1) /* arbitration lost */ +#define UNIPHIER_FI2C_SR 0x2c /* status register */ +#define UNIPHIER_FI2C_SR_DB BIT(12) /* device busy */ +#define UNIPHIER_FI2C_SR_STS BIT(11) /* stop condition detected */ +#define UNIPHIER_FI2C_SR_BB BIT(8) /* bus busy */ +#define UNIPHIER_FI2C_SR_RFF BIT(3) /* RX FIFO full */ +#define UNIPHIER_FI2C_SR_RNE BIT(2) /* RX FIFO not empty */ +#define UNIPHIER_FI2C_SR_TNF BIT(1) /* TX FIFO not full */ +#define UNIPHIER_FI2C_SR_TFE BIT(0) /* TX FIFO empty */ +#define UNIPHIER_FI2C_RST 0x34 /* reset control */ +#define UNIPHIER_FI2C_RST_TBRST BIT(2) /* clear TX FIFO */ +#define UNIPHIER_FI2C_RST_RBRST BIT(1) /* clear RX FIFO */ +#define UNIPHIER_FI2C_RST_RST BIT(0) /* forcible bus reset */ +#define UNIPHIER_FI2C_BM 0x38 /* bus monitor */ +#define UNIPHIER_FI2C_BM_SDAO BIT(3) /* output for SDA line */ +#define UNIPHIER_FI2C_BM_SDAS BIT(2) /* readback of SDA line */ +#define UNIPHIER_FI2C_BM_SCLO BIT(1) /* output for SCL line */ +#define UNIPHIER_FI2C_BM_SCLS BIT(0) /* readback of SCL line */ +#define UNIPHIER_FI2C_NOISE 0x3c /* noise filter control */ +#define UNIPHIER_FI2C_TBC 0x40 /* TX byte count setting */ +#define UNIPHIER_FI2C_RBC 0x44 /* RX byte count setting */ +#define UNIPHIER_FI2C_TBCM 0x48 /* TX byte count monitor */ +#define UNIPHIER_FI2C_RBCM 0x4c /* RX byte count monitor */ +#define UNIPHIER_FI2C_BRST 0x50 /* bus reset */ +#define UNIPHIER_FI2C_BRST_FOEN BIT(1) /* normal operation */ +#define UNIPHIER_FI2C_BRST_RSCL BIT(0) /* release SCL */ + +#define UNIPHIER_FI2C_INT_FAULTS \ + (UNIPHIER_FI2C_INT_NA | UNIPHIER_FI2C_INT_AL) +#define UNIPHIER_FI2C_INT_STOP \ + (UNIPHIER_FI2C_INT_TC | UNIPHIER_FI2C_INT_RC) + +#define UNIPHIER_FI2C_RD BIT(0) +#define UNIPHIER_FI2C_STOP BIT(1) +#define UNIPHIER_FI2C_MANUAL_NACK BIT(2) +#define UNIPHIER_FI2C_BYTE_WISE BIT(3) +#define UNIPHIER_FI2C_DEFER_STOP_COMP BIT(4) + +#define UNIPHIER_FI2C_FIFO_SIZE 8 + +struct uniphier_fi2c_priv { + struct completion comp; + struct i2c_adapter adap; + void __iomem *membase; + struct clk *clk; + unsigned int len; + u8 *buf; + u32 enabled_irqs; + int error; + unsigned int flags; + unsigned int busy_cnt; + unsigned int clk_cycle; + spinlock_t lock; /* IRQ synchronization */ +}; + +static void uniphier_fi2c_fill_txfifo(struct uniphier_fi2c_priv *priv, + bool first) +{ + int fifo_space = UNIPHIER_FI2C_FIFO_SIZE; + + /* + * TX-FIFO stores slave address in it for the first access. + * Decrement the counter. + */ + if (first) + fifo_space--; + + while (priv->len) { + if (fifo_space-- <= 0) + break; + + writel(*priv->buf++, priv->membase + UNIPHIER_FI2C_DTTX); + priv->len--; + } +} + +static void uniphier_fi2c_drain_rxfifo(struct uniphier_fi2c_priv *priv) +{ + int fifo_left = priv->flags & UNIPHIER_FI2C_BYTE_WISE ? + 1 : UNIPHIER_FI2C_FIFO_SIZE; + + while (priv->len) { + if (fifo_left-- <= 0) + break; + + *priv->buf++ = readl(priv->membase + UNIPHIER_FI2C_DTRX); + priv->len--; + } +} + +static void uniphier_fi2c_set_irqs(struct uniphier_fi2c_priv *priv) +{ + writel(priv->enabled_irqs, priv->membase + UNIPHIER_FI2C_IE); +} + +static void uniphier_fi2c_clear_irqs(struct uniphier_fi2c_priv *priv, + u32 mask) +{ + writel(mask, priv->membase + UNIPHIER_FI2C_IC); +} + +static void uniphier_fi2c_stop(struct uniphier_fi2c_priv *priv) +{ + priv->enabled_irqs |= UNIPHIER_FI2C_INT_STOP; + uniphier_fi2c_set_irqs(priv); + writel(UNIPHIER_FI2C_CR_MST | UNIPHIER_FI2C_CR_STO, + priv->membase + UNIPHIER_FI2C_CR); +} + +static irqreturn_t uniphier_fi2c_interrupt(int irq, void *dev_id) +{ + struct uniphier_fi2c_priv *priv = dev_id; + u32 irq_status; + + spin_lock(&priv->lock); + + irq_status = readl(priv->membase + UNIPHIER_FI2C_INT); + irq_status &= priv->enabled_irqs; + + if (irq_status & UNIPHIER_FI2C_INT_STOP) + goto complete; + + if (unlikely(irq_status & UNIPHIER_FI2C_INT_AL)) { + priv->error = -EAGAIN; + goto complete; + } + + if (unlikely(irq_status & UNIPHIER_FI2C_INT_NA)) { + priv->error = -ENXIO; + if (priv->flags & UNIPHIER_FI2C_RD) { + /* + * work around a hardware bug: + * The receive-completed interrupt is never set even if + * STOP condition is detected after the address phase + * of read transaction fails to get ACK. + * To avoid time-out error, we issue STOP here, + * but do not wait for its completion. + * It should be checked after exiting this handler. + */ + uniphier_fi2c_stop(priv); + priv->flags |= UNIPHIER_FI2C_DEFER_STOP_COMP; + goto complete; + } + goto stop; + } + + if (irq_status & UNIPHIER_FI2C_INT_TE) { + if (!priv->len) + goto data_done; + + uniphier_fi2c_fill_txfifo(priv, false); + goto handled; + } + + if (irq_status & (UNIPHIER_FI2C_INT_RF | UNIPHIER_FI2C_INT_RB)) { + uniphier_fi2c_drain_rxfifo(priv); + /* + * If the number of bytes to read is multiple of the FIFO size + * (msg->len == 8, 16, 24, ...), the INT_RF bit is set a little + * earlier than INT_RB. We wait for INT_RB to confirm the + * completion of the current message. + */ + if (!priv->len && (irq_status & UNIPHIER_FI2C_INT_RB)) + goto data_done; + + if (unlikely(priv->flags & UNIPHIER_FI2C_MANUAL_NACK)) { + if (priv->len <= UNIPHIER_FI2C_FIFO_SIZE && + !(priv->flags & UNIPHIER_FI2C_BYTE_WISE)) { + priv->enabled_irqs |= UNIPHIER_FI2C_INT_RB; + uniphier_fi2c_set_irqs(priv); + priv->flags |= UNIPHIER_FI2C_BYTE_WISE; + } + if (priv->len <= 1) + writel(UNIPHIER_FI2C_CR_MST | + UNIPHIER_FI2C_CR_NACK, + priv->membase + UNIPHIER_FI2C_CR); + } + + goto handled; + } + + spin_unlock(&priv->lock); + + return IRQ_NONE; + +data_done: + if (priv->flags & UNIPHIER_FI2C_STOP) { +stop: + uniphier_fi2c_stop(priv); + } else { +complete: + priv->enabled_irqs = 0; + uniphier_fi2c_set_irqs(priv); + complete(&priv->comp); + } + +handled: + /* + * This controller makes a pause while any bit of the IRQ status is + * asserted. Clear the asserted bit to kick the controller just before + * exiting the handler. + */ + uniphier_fi2c_clear_irqs(priv, irq_status); + + spin_unlock(&priv->lock); + + return IRQ_HANDLED; +} + +static void uniphier_fi2c_tx_init(struct uniphier_fi2c_priv *priv, u16 addr, + bool repeat) +{ + priv->enabled_irqs |= UNIPHIER_FI2C_INT_TE; + uniphier_fi2c_set_irqs(priv); + + /* do not use TX byte counter */ + writel(0, priv->membase + UNIPHIER_FI2C_TBC); + /* set slave address */ + writel(UNIPHIER_FI2C_DTTX_CMD | addr << 1, + priv->membase + UNIPHIER_FI2C_DTTX); + /* + * First chunk of data. For a repeated START condition, do not write + * data to the TX fifo here to avoid the timing issue. + */ + if (!repeat) + uniphier_fi2c_fill_txfifo(priv, true); +} + +static void uniphier_fi2c_rx_init(struct uniphier_fi2c_priv *priv, u16 addr) +{ + priv->flags |= UNIPHIER_FI2C_RD; + + if (likely(priv->len < 256)) { + /* + * If possible, use RX byte counter. + * It can automatically handle NACK for the last byte. + */ + writel(priv->len, priv->membase + UNIPHIER_FI2C_RBC); + priv->enabled_irqs |= UNIPHIER_FI2C_INT_RF | + UNIPHIER_FI2C_INT_RB; + } else { + /* + * The byte counter can not count over 256. In this case, + * do not use it at all. Drain data when FIFO gets full, + * but treat the last portion as a special case. + */ + writel(0, priv->membase + UNIPHIER_FI2C_RBC); + priv->flags |= UNIPHIER_FI2C_MANUAL_NACK; + priv->enabled_irqs |= UNIPHIER_FI2C_INT_RF; + } + + uniphier_fi2c_set_irqs(priv); + + /* set slave address with RD bit */ + writel(UNIPHIER_FI2C_DTTX_CMD | UNIPHIER_FI2C_DTTX_RD | addr << 1, + priv->membase + UNIPHIER_FI2C_DTTX); +} + +static void uniphier_fi2c_reset(struct uniphier_fi2c_priv *priv) +{ + writel(UNIPHIER_FI2C_RST_RST, priv->membase + UNIPHIER_FI2C_RST); +} + +static void uniphier_fi2c_prepare_operation(struct uniphier_fi2c_priv *priv) +{ + writel(UNIPHIER_FI2C_BRST_FOEN | UNIPHIER_FI2C_BRST_RSCL, + priv->membase + UNIPHIER_FI2C_BRST); +} + +static void uniphier_fi2c_recover(struct uniphier_fi2c_priv *priv) +{ + uniphier_fi2c_reset(priv); + i2c_recover_bus(&priv->adap); +} + +static int uniphier_fi2c_master_xfer_one(struct i2c_adapter *adap, + struct i2c_msg *msg, bool repeat, + bool stop) +{ + struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap); + bool is_read = msg->flags & I2C_M_RD; + unsigned long time_left, flags; + + priv->len = msg->len; + priv->buf = msg->buf; + priv->enabled_irqs = UNIPHIER_FI2C_INT_FAULTS; + priv->error = 0; + priv->flags = 0; + + if (stop) + priv->flags |= UNIPHIER_FI2C_STOP; + + reinit_completion(&priv->comp); + uniphier_fi2c_clear_irqs(priv, U32_MAX); + writel(UNIPHIER_FI2C_RST_TBRST | UNIPHIER_FI2C_RST_RBRST, + priv->membase + UNIPHIER_FI2C_RST); /* reset TX/RX FIFO */ + + spin_lock_irqsave(&priv->lock, flags); + + if (is_read) + uniphier_fi2c_rx_init(priv, msg->addr); + else + uniphier_fi2c_tx_init(priv, msg->addr, repeat); + + /* + * For a repeated START condition, writing a slave address to the FIFO + * kicks the controller. So, the UNIPHIER_FI2C_CR register should be + * written only for a non-repeated START condition. + */ + if (!repeat) + writel(UNIPHIER_FI2C_CR_MST | UNIPHIER_FI2C_CR_STA, + priv->membase + UNIPHIER_FI2C_CR); + + spin_unlock_irqrestore(&priv->lock, flags); + + time_left = wait_for_completion_timeout(&priv->comp, adap->timeout); + + spin_lock_irqsave(&priv->lock, flags); + priv->enabled_irqs = 0; + uniphier_fi2c_set_irqs(priv); + spin_unlock_irqrestore(&priv->lock, flags); + + if (!time_left) { + dev_err(&adap->dev, "transaction timeout.\n"); + uniphier_fi2c_recover(priv); + return -ETIMEDOUT; + } + + if (unlikely(priv->flags & UNIPHIER_FI2C_DEFER_STOP_COMP)) { + u32 status; + int ret; + + ret = readl_poll_timeout(priv->membase + UNIPHIER_FI2C_SR, + status, + (status & UNIPHIER_FI2C_SR_STS) && + !(status & UNIPHIER_FI2C_SR_BB), + 1, 20); + if (ret) { + dev_err(&adap->dev, + "stop condition was not completed.\n"); + uniphier_fi2c_recover(priv); + return ret; + } + } + + return priv->error; +} + +static int uniphier_fi2c_check_bus_busy(struct i2c_adapter *adap) +{ + struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap); + + if (readl(priv->membase + UNIPHIER_FI2C_SR) & UNIPHIER_FI2C_SR_DB) { + if (priv->busy_cnt++ > 3) { + /* + * If bus busy continues too long, it is probably + * in a wrong state. Try bus recovery. + */ + uniphier_fi2c_recover(priv); + priv->busy_cnt = 0; + } + + return -EAGAIN; + } + + priv->busy_cnt = 0; + return 0; +} + +static int uniphier_fi2c_master_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct i2c_msg *msg, *emsg = msgs + num; + bool repeat = false; + int ret; + + ret = uniphier_fi2c_check_bus_busy(adap); + if (ret) + return ret; + + for (msg = msgs; msg < emsg; msg++) { + /* Emit STOP if it is the last message or I2C_M_STOP is set. */ + bool stop = (msg + 1 == emsg) || (msg->flags & I2C_M_STOP); + + ret = uniphier_fi2c_master_xfer_one(adap, msg, repeat, stop); + if (ret) + return ret; + + repeat = !stop; + } + + return num; +} + +static u32 uniphier_fi2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm uniphier_fi2c_algo = { + .master_xfer = uniphier_fi2c_master_xfer, + .functionality = uniphier_fi2c_functionality, +}; + +static int uniphier_fi2c_get_scl(struct i2c_adapter *adap) +{ + struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap); + + return !!(readl(priv->membase + UNIPHIER_FI2C_BM) & + UNIPHIER_FI2C_BM_SCLS); +} + +static void uniphier_fi2c_set_scl(struct i2c_adapter *adap, int val) +{ + struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap); + + writel(val ? UNIPHIER_FI2C_BRST_RSCL : 0, + priv->membase + UNIPHIER_FI2C_BRST); +} + +static int uniphier_fi2c_get_sda(struct i2c_adapter *adap) +{ + struct uniphier_fi2c_priv *priv = i2c_get_adapdata(adap); + + return !!(readl(priv->membase + UNIPHIER_FI2C_BM) & + UNIPHIER_FI2C_BM_SDAS); +} + +static void uniphier_fi2c_unprepare_recovery(struct i2c_adapter *adap) +{ + uniphier_fi2c_prepare_operation(i2c_get_adapdata(adap)); +} + +static struct i2c_bus_recovery_info uniphier_fi2c_bus_recovery_info = { + .recover_bus = i2c_generic_scl_recovery, + .get_scl = uniphier_fi2c_get_scl, + .set_scl = uniphier_fi2c_set_scl, + .get_sda = uniphier_fi2c_get_sda, + .unprepare_recovery = uniphier_fi2c_unprepare_recovery, +}; + +static void uniphier_fi2c_hw_init(struct uniphier_fi2c_priv *priv) +{ + unsigned int cyc = priv->clk_cycle; + u32 tmp; + + tmp = readl(priv->membase + UNIPHIER_FI2C_CR); + tmp |= UNIPHIER_FI2C_CR_MST; + writel(tmp, priv->membase + UNIPHIER_FI2C_CR); + + uniphier_fi2c_reset(priv); + + /* + * Standard-mode: tLOW + tHIGH = 10 us + * Fast-mode: tLOW + tHIGH = 2.5 us + */ + writel(cyc, priv->membase + UNIPHIER_FI2C_CYC); + /* + * Standard-mode: tLOW = 4.7 us, tHIGH = 4.0 us, tBUF = 4.7 us + * Fast-mode: tLOW = 1.3 us, tHIGH = 0.6 us, tBUF = 1.3 us + * "tLow/tHIGH = 5/4" meets both. + */ + writel(cyc * 5 / 9, priv->membase + UNIPHIER_FI2C_LCTL); + /* + * Standard-mode: tHD;STA = 4.0 us, tSU;STA = 4.7 us, tSU;STO = 4.0 us + * Fast-mode: tHD;STA = 0.6 us, tSU;STA = 0.6 us, tSU;STO = 0.6 us + */ + writel(cyc / 2, priv->membase + UNIPHIER_FI2C_SSUT); + /* + * Standard-mode: tSU;DAT = 250 ns + * Fast-mode: tSU;DAT = 100 ns + */ + writel(cyc / 16, priv->membase + UNIPHIER_FI2C_DSUT); + + uniphier_fi2c_prepare_operation(priv); +} + +static int uniphier_fi2c_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct uniphier_fi2c_priv *priv; + u32 bus_speed; + unsigned long clk_rate; + int irq, ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->membase = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->membase)) + return PTR_ERR(priv->membase); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + if (of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed)) + bus_speed = I2C_MAX_STANDARD_MODE_FREQ; + + if (!bus_speed || bus_speed > I2C_MAX_FAST_MODE_FREQ) { + dev_err(dev, "invalid clock-frequency %d\n", bus_speed); + return -EINVAL; + } + + priv->clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(priv->clk)) { + dev_err(dev, "failed to enable clock\n"); + return PTR_ERR(priv->clk); + } + + clk_rate = clk_get_rate(priv->clk); + if (!clk_rate) { + dev_err(dev, "input clock rate should not be zero\n"); + return -EINVAL; + } + + priv->clk_cycle = clk_rate / bus_speed; + init_completion(&priv->comp); + spin_lock_init(&priv->lock); + priv->adap.owner = THIS_MODULE; + priv->adap.algo = &uniphier_fi2c_algo; + priv->adap.dev.parent = dev; + priv->adap.dev.of_node = dev->of_node; + strscpy(priv->adap.name, "UniPhier FI2C", sizeof(priv->adap.name)); + priv->adap.bus_recovery_info = &uniphier_fi2c_bus_recovery_info; + i2c_set_adapdata(&priv->adap, priv); + platform_set_drvdata(pdev, priv); + + uniphier_fi2c_hw_init(priv); + + ret = devm_request_irq(dev, irq, uniphier_fi2c_interrupt, 0, + pdev->name, priv); + if (ret) { + dev_err(dev, "failed to request irq %d\n", irq); + return ret; + } + + return i2c_add_adapter(&priv->adap); +} + +static void uniphier_fi2c_remove(struct platform_device *pdev) +{ + struct uniphier_fi2c_priv *priv = platform_get_drvdata(pdev); + + i2c_del_adapter(&priv->adap); +} + +static int __maybe_unused uniphier_fi2c_suspend(struct device *dev) +{ + struct uniphier_fi2c_priv *priv = dev_get_drvdata(dev); + + clk_disable_unprepare(priv->clk); + + return 0; +} + +static int __maybe_unused uniphier_fi2c_resume(struct device *dev) +{ + struct uniphier_fi2c_priv *priv = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(priv->clk); + if (ret) + return ret; + + uniphier_fi2c_hw_init(priv); + + return 0; +} + +static const struct dev_pm_ops uniphier_fi2c_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(uniphier_fi2c_suspend, uniphier_fi2c_resume) +}; + +static const struct of_device_id uniphier_fi2c_match[] = { + { .compatible = "socionext,uniphier-fi2c" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, uniphier_fi2c_match); + +static struct platform_driver uniphier_fi2c_drv = { + .probe = uniphier_fi2c_probe, + .remove_new = uniphier_fi2c_remove, + .driver = { + .name = "uniphier-fi2c", + .of_match_table = uniphier_fi2c_match, + .pm = &uniphier_fi2c_pm_ops, + }, +}; +module_platform_driver(uniphier_fi2c_drv); + +MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>"); +MODULE_DESCRIPTION("UniPhier FIFO-builtin I2C bus driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-uniphier.c b/drivers/i2c/busses/i2c-uniphier.c new file mode 100644 index 000000000..854ac25b5 --- /dev/null +++ b/drivers/i2c/busses/i2c-uniphier.c @@ -0,0 +1,426 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com> + */ + +#include <linux/clk.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +#define UNIPHIER_I2C_DTRM 0x00 /* TX register */ +#define UNIPHIER_I2C_DTRM_IRQEN BIT(11) /* enable interrupt */ +#define UNIPHIER_I2C_DTRM_STA BIT(10) /* start condition */ +#define UNIPHIER_I2C_DTRM_STO BIT(9) /* stop condition */ +#define UNIPHIER_I2C_DTRM_NACK BIT(8) /* do not return ACK */ +#define UNIPHIER_I2C_DTRM_RD BIT(0) /* read transaction */ +#define UNIPHIER_I2C_DREC 0x04 /* RX register */ +#define UNIPHIER_I2C_DREC_MST BIT(14) /* 1 = master, 0 = slave */ +#define UNIPHIER_I2C_DREC_TX BIT(13) /* 1 = transmit, 0 = receive */ +#define UNIPHIER_I2C_DREC_STS BIT(12) /* stop condition detected */ +#define UNIPHIER_I2C_DREC_LRB BIT(11) /* no ACK */ +#define UNIPHIER_I2C_DREC_LAB BIT(9) /* arbitration lost */ +#define UNIPHIER_I2C_DREC_BBN BIT(8) /* bus not busy */ +#define UNIPHIER_I2C_MYAD 0x08 /* slave address */ +#define UNIPHIER_I2C_CLK 0x0c /* clock frequency control */ +#define UNIPHIER_I2C_BRST 0x10 /* bus reset */ +#define UNIPHIER_I2C_BRST_FOEN BIT(1) /* normal operation */ +#define UNIPHIER_I2C_BRST_RSCL BIT(0) /* release SCL */ +#define UNIPHIER_I2C_HOLD 0x14 /* hold time control */ +#define UNIPHIER_I2C_BSTS 0x18 /* bus status monitor */ +#define UNIPHIER_I2C_BSTS_SDA BIT(1) /* readback of SDA line */ +#define UNIPHIER_I2C_BSTS_SCL BIT(0) /* readback of SCL line */ +#define UNIPHIER_I2C_NOISE 0x1c /* noise filter control */ +#define UNIPHIER_I2C_SETUP 0x20 /* setup time control */ + +struct uniphier_i2c_priv { + struct completion comp; + struct i2c_adapter adap; + void __iomem *membase; + struct clk *clk; + unsigned int busy_cnt; + unsigned int clk_cycle; +}; + +static irqreturn_t uniphier_i2c_interrupt(int irq, void *dev_id) +{ + struct uniphier_i2c_priv *priv = dev_id; + + /* + * This hardware uses edge triggered interrupt. Do not touch the + * hardware registers in this handler to make sure to catch the next + * interrupt edge. Just send a complete signal and return. + */ + complete(&priv->comp); + + return IRQ_HANDLED; +} + +static int uniphier_i2c_xfer_byte(struct i2c_adapter *adap, u32 txdata, + u32 *rxdatap) +{ + struct uniphier_i2c_priv *priv = i2c_get_adapdata(adap); + unsigned long time_left; + u32 rxdata; + + reinit_completion(&priv->comp); + + txdata |= UNIPHIER_I2C_DTRM_IRQEN; + writel(txdata, priv->membase + UNIPHIER_I2C_DTRM); + + time_left = wait_for_completion_timeout(&priv->comp, adap->timeout); + if (unlikely(!time_left)) { + dev_err(&adap->dev, "transaction timeout\n"); + return -ETIMEDOUT; + } + + rxdata = readl(priv->membase + UNIPHIER_I2C_DREC); + if (rxdatap) + *rxdatap = rxdata; + + return 0; +} + +static int uniphier_i2c_send_byte(struct i2c_adapter *adap, u32 txdata) +{ + u32 rxdata; + int ret; + + ret = uniphier_i2c_xfer_byte(adap, txdata, &rxdata); + if (ret) + return ret; + + if (unlikely(rxdata & UNIPHIER_I2C_DREC_LAB)) + return -EAGAIN; + + if (unlikely(rxdata & UNIPHIER_I2C_DREC_LRB)) + return -ENXIO; + + return 0; +} + +static int uniphier_i2c_tx(struct i2c_adapter *adap, u16 addr, u16 len, + const u8 *buf) +{ + int ret; + + ret = uniphier_i2c_send_byte(adap, addr << 1 | + UNIPHIER_I2C_DTRM_STA | + UNIPHIER_I2C_DTRM_NACK); + if (ret) + return ret; + + while (len--) { + ret = uniphier_i2c_send_byte(adap, + UNIPHIER_I2C_DTRM_NACK | *buf++); + if (ret) + return ret; + } + + return 0; +} + +static int uniphier_i2c_rx(struct i2c_adapter *adap, u16 addr, u16 len, + u8 *buf) +{ + int ret; + + ret = uniphier_i2c_send_byte(adap, addr << 1 | + UNIPHIER_I2C_DTRM_STA | + UNIPHIER_I2C_DTRM_NACK | + UNIPHIER_I2C_DTRM_RD); + if (ret) + return ret; + + while (len--) { + u32 rxdata; + + ret = uniphier_i2c_xfer_byte(adap, + len ? 0 : UNIPHIER_I2C_DTRM_NACK, + &rxdata); + if (ret) + return ret; + *buf++ = rxdata; + } + + return 0; +} + +static int uniphier_i2c_stop(struct i2c_adapter *adap) +{ + return uniphier_i2c_send_byte(adap, UNIPHIER_I2C_DTRM_STO | + UNIPHIER_I2C_DTRM_NACK); +} + +static int uniphier_i2c_master_xfer_one(struct i2c_adapter *adap, + struct i2c_msg *msg, bool stop) +{ + bool is_read = msg->flags & I2C_M_RD; + bool recovery = false; + int ret; + + if (is_read) + ret = uniphier_i2c_rx(adap, msg->addr, msg->len, msg->buf); + else + ret = uniphier_i2c_tx(adap, msg->addr, msg->len, msg->buf); + + if (ret == -EAGAIN) /* could not acquire bus. bail out without STOP */ + return ret; + + if (ret == -ETIMEDOUT) { + /* This error is fatal. Needs recovery. */ + stop = false; + recovery = true; + } + + if (stop) { + int ret2 = uniphier_i2c_stop(adap); + + if (ret2) { + /* Failed to issue STOP. The bus needs recovery. */ + recovery = true; + ret = ret ?: ret2; + } + } + + if (recovery) + i2c_recover_bus(adap); + + return ret; +} + +static int uniphier_i2c_check_bus_busy(struct i2c_adapter *adap) +{ + struct uniphier_i2c_priv *priv = i2c_get_adapdata(adap); + + if (!(readl(priv->membase + UNIPHIER_I2C_DREC) & + UNIPHIER_I2C_DREC_BBN)) { + if (priv->busy_cnt++ > 3) { + /* + * If bus busy continues too long, it is probably + * in a wrong state. Try bus recovery. + */ + i2c_recover_bus(adap); + priv->busy_cnt = 0; + } + + return -EAGAIN; + } + + priv->busy_cnt = 0; + return 0; +} + +static int uniphier_i2c_master_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct i2c_msg *msg, *emsg = msgs + num; + int ret; + + ret = uniphier_i2c_check_bus_busy(adap); + if (ret) + return ret; + + for (msg = msgs; msg < emsg; msg++) { + /* Emit STOP if it is the last message or I2C_M_STOP is set. */ + bool stop = (msg + 1 == emsg) || (msg->flags & I2C_M_STOP); + + ret = uniphier_i2c_master_xfer_one(adap, msg, stop); + if (ret) + return ret; + } + + return num; +} + +static u32 uniphier_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm uniphier_i2c_algo = { + .master_xfer = uniphier_i2c_master_xfer, + .functionality = uniphier_i2c_functionality, +}; + +static void uniphier_i2c_reset(struct uniphier_i2c_priv *priv, bool reset_on) +{ + u32 val = UNIPHIER_I2C_BRST_RSCL; + + val |= reset_on ? 0 : UNIPHIER_I2C_BRST_FOEN; + writel(val, priv->membase + UNIPHIER_I2C_BRST); +} + +static int uniphier_i2c_get_scl(struct i2c_adapter *adap) +{ + struct uniphier_i2c_priv *priv = i2c_get_adapdata(adap); + + return !!(readl(priv->membase + UNIPHIER_I2C_BSTS) & + UNIPHIER_I2C_BSTS_SCL); +} + +static void uniphier_i2c_set_scl(struct i2c_adapter *adap, int val) +{ + struct uniphier_i2c_priv *priv = i2c_get_adapdata(adap); + + writel(val ? UNIPHIER_I2C_BRST_RSCL : 0, + priv->membase + UNIPHIER_I2C_BRST); +} + +static int uniphier_i2c_get_sda(struct i2c_adapter *adap) +{ + struct uniphier_i2c_priv *priv = i2c_get_adapdata(adap); + + return !!(readl(priv->membase + UNIPHIER_I2C_BSTS) & + UNIPHIER_I2C_BSTS_SDA); +} + +static void uniphier_i2c_unprepare_recovery(struct i2c_adapter *adap) +{ + uniphier_i2c_reset(i2c_get_adapdata(adap), false); +} + +static struct i2c_bus_recovery_info uniphier_i2c_bus_recovery_info = { + .recover_bus = i2c_generic_scl_recovery, + .get_scl = uniphier_i2c_get_scl, + .set_scl = uniphier_i2c_set_scl, + .get_sda = uniphier_i2c_get_sda, + .unprepare_recovery = uniphier_i2c_unprepare_recovery, +}; + +static void uniphier_i2c_hw_init(struct uniphier_i2c_priv *priv) +{ + unsigned int cyc = priv->clk_cycle; + + uniphier_i2c_reset(priv, true); + + /* + * Bit30-16: clock cycles of tLOW. + * Standard-mode: tLOW = 4.7 us, tHIGH = 4.0 us + * Fast-mode: tLOW = 1.3 us, tHIGH = 0.6 us + * "tLow/tHIGH = 5/4" meets both. + */ + writel((cyc * 5 / 9 << 16) | cyc, priv->membase + UNIPHIER_I2C_CLK); + + uniphier_i2c_reset(priv, false); +} + +static int uniphier_i2c_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct uniphier_i2c_priv *priv; + u32 bus_speed; + unsigned long clk_rate; + int irq, ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->membase = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->membase)) + return PTR_ERR(priv->membase); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + if (of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed)) + bus_speed = I2C_MAX_STANDARD_MODE_FREQ; + + if (!bus_speed || bus_speed > I2C_MAX_FAST_MODE_FREQ) { + dev_err(dev, "invalid clock-frequency %d\n", bus_speed); + return -EINVAL; + } + + priv->clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(priv->clk)) { + dev_err(dev, "failed to enable clock\n"); + return PTR_ERR(priv->clk); + } + + clk_rate = clk_get_rate(priv->clk); + if (!clk_rate) { + dev_err(dev, "input clock rate should not be zero\n"); + return -EINVAL; + } + + priv->clk_cycle = clk_rate / bus_speed; + init_completion(&priv->comp); + priv->adap.owner = THIS_MODULE; + priv->adap.algo = &uniphier_i2c_algo; + priv->adap.dev.parent = dev; + priv->adap.dev.of_node = dev->of_node; + strscpy(priv->adap.name, "UniPhier I2C", sizeof(priv->adap.name)); + priv->adap.bus_recovery_info = &uniphier_i2c_bus_recovery_info; + i2c_set_adapdata(&priv->adap, priv); + platform_set_drvdata(pdev, priv); + + uniphier_i2c_hw_init(priv); + + ret = devm_request_irq(dev, irq, uniphier_i2c_interrupt, 0, pdev->name, + priv); + if (ret) { + dev_err(dev, "failed to request irq %d\n", irq); + return ret; + } + + return i2c_add_adapter(&priv->adap); +} + +static void uniphier_i2c_remove(struct platform_device *pdev) +{ + struct uniphier_i2c_priv *priv = platform_get_drvdata(pdev); + + i2c_del_adapter(&priv->adap); +} + +static int __maybe_unused uniphier_i2c_suspend(struct device *dev) +{ + struct uniphier_i2c_priv *priv = dev_get_drvdata(dev); + + clk_disable_unprepare(priv->clk); + + return 0; +} + +static int __maybe_unused uniphier_i2c_resume(struct device *dev) +{ + struct uniphier_i2c_priv *priv = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(priv->clk); + if (ret) + return ret; + + uniphier_i2c_hw_init(priv); + + return 0; +} + +static const struct dev_pm_ops uniphier_i2c_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(uniphier_i2c_suspend, uniphier_i2c_resume) +}; + +static const struct of_device_id uniphier_i2c_match[] = { + { .compatible = "socionext,uniphier-i2c" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, uniphier_i2c_match); + +static struct platform_driver uniphier_i2c_drv = { + .probe = uniphier_i2c_probe, + .remove_new = uniphier_i2c_remove, + .driver = { + .name = "uniphier-i2c", + .of_match_table = uniphier_i2c_match, + .pm = &uniphier_i2c_pm_ops, + }, +}; +module_platform_driver(uniphier_i2c_drv); + +MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>"); +MODULE_DESCRIPTION("UniPhier I2C bus driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-versatile.c b/drivers/i2c/busses/i2c-versatile.c new file mode 100644 index 000000000..76abfa77e --- /dev/null +++ b/drivers/i2c/busses/i2c-versatile.c @@ -0,0 +1,134 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * i2c-versatile.c + * + * Copyright (C) 2006 ARM Ltd. + * written by Russell King, Deep Blue Solutions Ltd. + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/i2c-algo-bit.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/io.h> + +#define I2C_CONTROL 0x00 +#define I2C_CONTROLS 0x00 +#define I2C_CONTROLC 0x04 +#define SCL (1 << 0) +#define SDA (1 << 1) + +struct i2c_versatile { + struct i2c_adapter adap; + struct i2c_algo_bit_data algo; + void __iomem *base; +}; + +static void i2c_versatile_setsda(void *data, int state) +{ + struct i2c_versatile *i2c = data; + + writel(SDA, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC)); +} + +static void i2c_versatile_setscl(void *data, int state) +{ + struct i2c_versatile *i2c = data; + + writel(SCL, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC)); +} + +static int i2c_versatile_getsda(void *data) +{ + struct i2c_versatile *i2c = data; + return !!(readl(i2c->base + I2C_CONTROL) & SDA); +} + +static int i2c_versatile_getscl(void *data) +{ + struct i2c_versatile *i2c = data; + return !!(readl(i2c->base + I2C_CONTROL) & SCL); +} + +static const struct i2c_algo_bit_data i2c_versatile_algo = { + .setsda = i2c_versatile_setsda, + .setscl = i2c_versatile_setscl, + .getsda = i2c_versatile_getsda, + .getscl = i2c_versatile_getscl, + .udelay = 30, + .timeout = HZ, +}; + +static int i2c_versatile_probe(struct platform_device *dev) +{ + struct i2c_versatile *i2c; + int ret; + + i2c = devm_kzalloc(&dev->dev, sizeof(struct i2c_versatile), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->base = devm_platform_get_and_ioremap_resource(dev, 0, NULL); + if (IS_ERR(i2c->base)) + return PTR_ERR(i2c->base); + + writel(SCL | SDA, i2c->base + I2C_CONTROLS); + + i2c->adap.owner = THIS_MODULE; + strscpy(i2c->adap.name, "Versatile I2C adapter", sizeof(i2c->adap.name)); + i2c->adap.algo_data = &i2c->algo; + i2c->adap.dev.parent = &dev->dev; + i2c->adap.dev.of_node = dev->dev.of_node; + i2c->algo = i2c_versatile_algo; + i2c->algo.data = i2c; + + i2c->adap.nr = dev->id; + ret = i2c_bit_add_numbered_bus(&i2c->adap); + if (ret < 0) + return ret; + + platform_set_drvdata(dev, i2c); + + return 0; +} + +static void i2c_versatile_remove(struct platform_device *dev) +{ + struct i2c_versatile *i2c = platform_get_drvdata(dev); + + i2c_del_adapter(&i2c->adap); +} + +static const struct of_device_id i2c_versatile_match[] = { + { .compatible = "arm,versatile-i2c", }, + {}, +}; +MODULE_DEVICE_TABLE(of, i2c_versatile_match); + +static struct platform_driver i2c_versatile_driver = { + .probe = i2c_versatile_probe, + .remove_new = i2c_versatile_remove, + .driver = { + .name = "versatile-i2c", + .of_match_table = i2c_versatile_match, + }, +}; + +static int __init i2c_versatile_init(void) +{ + return platform_driver_register(&i2c_versatile_driver); +} + +static void __exit i2c_versatile_exit(void) +{ + platform_driver_unregister(&i2c_versatile_driver); +} + +subsys_initcall(i2c_versatile_init); +module_exit(i2c_versatile_exit); + +MODULE_DESCRIPTION("ARM Versatile I2C bus driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:versatile-i2c"); diff --git a/drivers/i2c/busses/i2c-via.c b/drivers/i2c/busses/i2c-via.c new file mode 100644 index 000000000..ad4f09c7f --- /dev/null +++ b/drivers/i2c/busses/i2c-via.c @@ -0,0 +1,155 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + i2c Support for Via Technologies 82C586B South Bridge + + Copyright (c) 1998, 1999 Kyösti Mälkki <kmalkki@cc.hut.fi> + +*/ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/ioport.h> +#include <linux/i2c.h> +#include <linux/i2c-algo-bit.h> +#include <linux/io.h> + +/* Power management registers */ +#define PM_CFG_REVID 0x08 /* silicon revision code */ +#define PM_CFG_IOBASE0 0x20 +#define PM_CFG_IOBASE1 0x48 + +#define I2C_DIR (pm_io_base+0x40) +#define I2C_OUT (pm_io_base+0x42) +#define I2C_IN (pm_io_base+0x44) +#define I2C_SCL 0x02 /* clock bit in DIR/OUT/IN register */ +#define I2C_SDA 0x04 + +/* io-region reservation */ +#define IOSPACE 0x06 + +static struct pci_driver vt586b_driver; +static u16 pm_io_base; + +/* + It does not appear from the datasheet that the GPIO pins are + open drain. So a we set a low value by setting the direction to + output and a high value by setting the direction to input and + relying on the required I2C pullup. The data value is initialized + to 0 in via_init() and never changed. +*/ +static void bit_via_setscl(void *data, int state) +{ + outb(state ? inb(I2C_DIR) & ~I2C_SCL : inb(I2C_DIR) | I2C_SCL, I2C_DIR); +} + +static void bit_via_setsda(void *data, int state) +{ + outb(state ? inb(I2C_DIR) & ~I2C_SDA : inb(I2C_DIR) | I2C_SDA, I2C_DIR); +} + +static int bit_via_getscl(void *data) +{ + return (0 != (inb(I2C_IN) & I2C_SCL)); +} + +static int bit_via_getsda(void *data) +{ + return (0 != (inb(I2C_IN) & I2C_SDA)); +} + + +static struct i2c_algo_bit_data bit_data = { + .setsda = bit_via_setsda, + .setscl = bit_via_setscl, + .getsda = bit_via_getsda, + .getscl = bit_via_getscl, + .udelay = 5, + .timeout = HZ +}; + +static struct i2c_adapter vt586b_adapter = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .name = "VIA i2c", + .algo_data = &bit_data, +}; + + +static const struct pci_device_id vt586b_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C586_3) }, + { 0, } +}; + +MODULE_DEVICE_TABLE (pci, vt586b_ids); + +static int vt586b_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + u16 base; + u8 rev; + int res; + + if (pm_io_base) { + dev_err(&dev->dev, "i2c-via: Will only support one host\n"); + return -ENODEV; + } + + pci_read_config_byte(dev, PM_CFG_REVID, &rev); + + switch (rev) { + case 0x00: + base = PM_CFG_IOBASE0; + break; + case 0x01: + case 0x10: + base = PM_CFG_IOBASE1; + break; + + default: + base = PM_CFG_IOBASE1; + /* later revision */ + } + + pci_read_config_word(dev, base, &pm_io_base); + pm_io_base &= (0xff << 8); + + if (!request_region(I2C_DIR, IOSPACE, vt586b_driver.name)) { + dev_err(&dev->dev, "IO 0x%x-0x%x already in use\n", I2C_DIR, I2C_DIR + IOSPACE); + return -ENODEV; + } + + outb(inb(I2C_DIR) & ~(I2C_SDA | I2C_SCL), I2C_DIR); + outb(inb(I2C_OUT) & ~(I2C_SDA | I2C_SCL), I2C_OUT); + + /* set up the sysfs linkage to our parent device */ + vt586b_adapter.dev.parent = &dev->dev; + + res = i2c_bit_add_bus(&vt586b_adapter); + if ( res < 0 ) { + release_region(I2C_DIR, IOSPACE); + pm_io_base = 0; + return res; + } + return 0; +} + +static void vt586b_remove(struct pci_dev *dev) +{ + i2c_del_adapter(&vt586b_adapter); + release_region(I2C_DIR, IOSPACE); + pm_io_base = 0; +} + + +static struct pci_driver vt586b_driver = { + .name = "vt586b_smbus", + .id_table = vt586b_ids, + .probe = vt586b_probe, + .remove = vt586b_remove, +}; + +module_pci_driver(vt586b_driver); + +MODULE_AUTHOR("Kyösti Mälkki <kmalkki@cc.hut.fi>"); +MODULE_DESCRIPTION("i2c for Via vt82c586b southbridge"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-viapro.c b/drivers/i2c/busses/i2c-viapro.c new file mode 100644 index 000000000..970ccdcbb --- /dev/null +++ b/drivers/i2c/busses/i2c-viapro.c @@ -0,0 +1,499 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl>, + Philip Edelbrock <phil@netroedge.com>, Kyösti Mälkki <kmalkki@cc.hut.fi>, + Mark D. Studebaker <mdsxyz123@yahoo.com> + Copyright (C) 2005 - 2008 Jean Delvare <jdelvare@suse.de> + +*/ + +/* + Supports the following VIA south bridges: + + Chip name PCI ID REV I2C block + VT82C596A 0x3050 no + VT82C596B 0x3051 no + VT82C686A 0x3057 0x30 no + VT82C686B 0x3057 0x40 yes + VT8231 0x8235 no? + VT8233 0x3074 yes + VT8233A 0x3147 yes? + VT8235 0x3177 yes + VT8237R 0x3227 yes + VT8237A 0x3337 yes + VT8237S 0x3372 yes + VT8251 0x3287 yes + CX700 0x8324 yes + VX800/VX820 0x8353 yes + VX855/VX875 0x8409 yes + + Note: we assume there can only be one device, with one SMBus interface. +*/ + +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/pci.h> +#include <linux/kernel.h> +#include <linux/stddef.h> +#include <linux/ioport.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/acpi.h> +#include <linux/io.h> + +static struct pci_dev *vt596_pdev; + +#define SMBBA1 0x90 +#define SMBBA2 0x80 +#define SMBBA3 0xD0 + +/* SMBus address offsets */ +static unsigned short vt596_smba; +#define SMBHSTSTS (vt596_smba + 0) +#define SMBHSTCNT (vt596_smba + 2) +#define SMBHSTCMD (vt596_smba + 3) +#define SMBHSTADD (vt596_smba + 4) +#define SMBHSTDAT0 (vt596_smba + 5) +#define SMBHSTDAT1 (vt596_smba + 6) +#define SMBBLKDAT (vt596_smba + 7) + +/* PCI Address Constants */ + +/* SMBus data in configuration space can be found in two places, + We try to select the better one */ + +static unsigned short SMBHSTCFG = 0xD2; + +/* Other settings */ +#define MAX_TIMEOUT 500 + +/* VT82C596 constants */ +#define VT596_QUICK 0x00 +#define VT596_BYTE 0x04 +#define VT596_BYTE_DATA 0x08 +#define VT596_WORD_DATA 0x0C +#define VT596_PROC_CALL 0x10 +#define VT596_BLOCK_DATA 0x14 +#define VT596_I2C_BLOCK_DATA 0x34 + + +/* If force is set to anything different from 0, we forcibly enable the + VT596. DANGEROUS! */ +static bool force; +module_param(force, bool, 0); +MODULE_PARM_DESC(force, "Forcibly enable the SMBus. DANGEROUS!"); + +/* If force_addr is set to anything different from 0, we forcibly enable + the VT596 at the given address. VERY DANGEROUS! */ +static u16 force_addr; +module_param_hw(force_addr, ushort, ioport, 0); +MODULE_PARM_DESC(force_addr, + "Forcibly enable the SMBus at the given address. " + "EXTREMELY DANGEROUS!"); + + +static struct pci_driver vt596_driver; +static struct i2c_adapter vt596_adapter; + +#define FEATURE_I2CBLOCK (1<<0) +static unsigned int vt596_features; + +#ifdef DEBUG +static void vt596_dump_regs(const char *msg, u8 size) +{ + dev_dbg(&vt596_adapter.dev, "%s: STS=%02x CNT=%02x CMD=%02x ADD=%02x " + "DAT=%02x,%02x\n", msg, inb_p(SMBHSTSTS), inb_p(SMBHSTCNT), + inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), + inb_p(SMBHSTDAT1)); + + if (size == VT596_BLOCK_DATA + || size == VT596_I2C_BLOCK_DATA) { + int i; + + dev_dbg(&vt596_adapter.dev, "BLK="); + for (i = 0; i < I2C_SMBUS_BLOCK_MAX / 2; i++) + printk("%02x,", inb_p(SMBBLKDAT)); + printk("\n"); + dev_dbg(&vt596_adapter.dev, " "); + for (; i < I2C_SMBUS_BLOCK_MAX - 1; i++) + printk("%02x,", inb_p(SMBBLKDAT)); + printk("%02x\n", inb_p(SMBBLKDAT)); + } +} +#else +static inline void vt596_dump_regs(const char *msg, u8 size) { } +#endif + +/* Return -1 on error, 0 on success */ +static int vt596_transaction(u8 size) +{ + int temp; + int result = 0; + int timeout = 0; + + vt596_dump_regs("Transaction (pre)", size); + + /* Make sure the SMBus host is ready to start transmitting */ + if ((temp = inb_p(SMBHSTSTS)) & 0x1F) { + dev_dbg(&vt596_adapter.dev, "SMBus busy (0x%02x). " + "Resetting...\n", temp); + + outb_p(temp, SMBHSTSTS); + if ((temp = inb_p(SMBHSTSTS)) & 0x1F) { + dev_err(&vt596_adapter.dev, "SMBus reset failed! " + "(0x%02x)\n", temp); + return -EBUSY; + } + } + + /* Start the transaction by setting bit 6 */ + outb_p(0x40 | size, SMBHSTCNT); + + /* We will always wait for a fraction of a second */ + do { + msleep(1); + temp = inb_p(SMBHSTSTS); + } while ((temp & 0x01) && (++timeout < MAX_TIMEOUT)); + + /* If the SMBus is still busy, we give up */ + if (timeout == MAX_TIMEOUT) { + result = -ETIMEDOUT; + dev_err(&vt596_adapter.dev, "SMBus timeout!\n"); + } + + if (temp & 0x10) { + result = -EIO; + dev_err(&vt596_adapter.dev, "Transaction failed (0x%02x)\n", + size); + } + + if (temp & 0x08) { + result = -EIO; + dev_err(&vt596_adapter.dev, "SMBus collision!\n"); + } + + if (temp & 0x04) { + result = -ENXIO; + dev_dbg(&vt596_adapter.dev, "No response\n"); + } + + /* Resetting status register */ + if (temp & 0x1F) + outb_p(temp, SMBHSTSTS); + + vt596_dump_regs("Transaction (post)", size); + + return result; +} + +/* Return negative errno on error, 0 on success */ +static s32 vt596_access(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, u8 command, + int size, union i2c_smbus_data *data) +{ + int i; + int status; + + switch (size) { + case I2C_SMBUS_QUICK: + size = VT596_QUICK; + break; + case I2C_SMBUS_BYTE: + if (read_write == I2C_SMBUS_WRITE) + outb_p(command, SMBHSTCMD); + size = VT596_BYTE; + break; + case I2C_SMBUS_BYTE_DATA: + outb_p(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) + outb_p(data->byte, SMBHSTDAT0); + size = VT596_BYTE_DATA; + break; + case I2C_SMBUS_WORD_DATA: + outb_p(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) { + outb_p(data->word & 0xff, SMBHSTDAT0); + outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1); + } + size = VT596_WORD_DATA; + break; + case I2C_SMBUS_PROC_CALL: + outb_p(command, SMBHSTCMD); + outb_p(data->word & 0xff, SMBHSTDAT0); + outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1); + size = VT596_PROC_CALL; + break; + case I2C_SMBUS_I2C_BLOCK_DATA: + if (!(vt596_features & FEATURE_I2CBLOCK)) + goto exit_unsupported; + if (read_write == I2C_SMBUS_READ) + outb_p(data->block[0], SMBHSTDAT0); + fallthrough; + case I2C_SMBUS_BLOCK_DATA: + outb_p(command, SMBHSTCMD); + if (read_write == I2C_SMBUS_WRITE) { + u8 len = data->block[0]; + if (len > I2C_SMBUS_BLOCK_MAX) + len = I2C_SMBUS_BLOCK_MAX; + outb_p(len, SMBHSTDAT0); + inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */ + for (i = 1; i <= len; i++) + outb_p(data->block[i], SMBBLKDAT); + } + size = (size == I2C_SMBUS_I2C_BLOCK_DATA) ? + VT596_I2C_BLOCK_DATA : VT596_BLOCK_DATA; + break; + default: + goto exit_unsupported; + } + + outb_p(((addr & 0x7f) << 1) | read_write, SMBHSTADD); + + status = vt596_transaction(size); + if (status) + return status; + + if (size == VT596_PROC_CALL) + read_write = I2C_SMBUS_READ; + + if ((read_write == I2C_SMBUS_WRITE) || (size == VT596_QUICK)) + return 0; + + switch (size) { + case VT596_BYTE: + case VT596_BYTE_DATA: + data->byte = inb_p(SMBHSTDAT0); + break; + case VT596_WORD_DATA: + case VT596_PROC_CALL: + data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8); + break; + case VT596_I2C_BLOCK_DATA: + case VT596_BLOCK_DATA: + data->block[0] = inb_p(SMBHSTDAT0); + if (data->block[0] > I2C_SMBUS_BLOCK_MAX) + data->block[0] = I2C_SMBUS_BLOCK_MAX; + inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */ + for (i = 1; i <= data->block[0]; i++) + data->block[i] = inb_p(SMBBLKDAT); + break; + } + return 0; + +exit_unsupported: + dev_warn(&vt596_adapter.dev, "Unsupported transaction %d\n", + size); + return -EOPNOTSUPP; +} + +static u32 vt596_func(struct i2c_adapter *adapter) +{ + u32 func = I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_BLOCK_DATA; + + if (vt596_features & FEATURE_I2CBLOCK) + func |= I2C_FUNC_SMBUS_I2C_BLOCK; + return func; +} + +static const struct i2c_algorithm smbus_algorithm = { + .smbus_xfer = vt596_access, + .functionality = vt596_func, +}; + +static struct i2c_adapter vt596_adapter = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = &smbus_algorithm, +}; + +static int vt596_probe(struct pci_dev *pdev, + const struct pci_device_id *id) +{ + unsigned char temp; + int error; + + /* Determine the address of the SMBus areas */ + if (force_addr) { + vt596_smba = force_addr & 0xfff0; + force = 0; + goto found; + } + + if ((pci_read_config_word(pdev, id->driver_data, &vt596_smba)) || + !(vt596_smba & 0x0001)) { + /* try 2nd address and config reg. for 596 */ + if (id->device == PCI_DEVICE_ID_VIA_82C596_3 && + !pci_read_config_word(pdev, SMBBA2, &vt596_smba) && + (vt596_smba & 0x0001)) { + SMBHSTCFG = 0x84; + } else { + /* no matches at all */ + dev_err(&pdev->dev, "Cannot configure " + "SMBus I/O Base address\n"); + return -ENODEV; + } + } + + vt596_smba &= 0xfff0; + if (vt596_smba == 0) { + dev_err(&pdev->dev, "SMBus base address " + "uninitialized - upgrade BIOS or use " + "force_addr=0xaddr\n"); + return -ENODEV; + } + +found: + error = acpi_check_region(vt596_smba, 8, vt596_driver.name); + if (error) + return -ENODEV; + + if (!request_region(vt596_smba, 8, vt596_driver.name)) { + dev_err(&pdev->dev, "SMBus region 0x%x already in use!\n", + vt596_smba); + return -ENODEV; + } + + pci_read_config_byte(pdev, SMBHSTCFG, &temp); + /* If force_addr is set, we program the new address here. Just to make + sure, we disable the VT596 first. */ + if (force_addr) { + pci_write_config_byte(pdev, SMBHSTCFG, temp & 0xfe); + pci_write_config_word(pdev, id->driver_data, vt596_smba); + pci_write_config_byte(pdev, SMBHSTCFG, temp | 0x01); + dev_warn(&pdev->dev, "WARNING: SMBus interface set to new " + "address 0x%04x!\n", vt596_smba); + } else if (!(temp & 0x01)) { + if (force) { + /* NOTE: This assumes I/O space and other allocations + * WERE done by the Bios! Don't complain if your + * hardware does weird things after enabling this. + * :') Check for Bios updates before resorting to + * this. + */ + pci_write_config_byte(pdev, SMBHSTCFG, temp | 0x01); + dev_info(&pdev->dev, "Enabling SMBus device\n"); + } else { + dev_err(&pdev->dev, "SMBUS: Error: Host SMBus " + "controller not enabled! - upgrade BIOS or " + "use force=1\n"); + error = -ENODEV; + goto release_region; + } + } + + dev_dbg(&pdev->dev, "VT596_smba = 0x%X\n", vt596_smba); + + switch (pdev->device) { + case PCI_DEVICE_ID_VIA_CX700: + case PCI_DEVICE_ID_VIA_VX800: + case PCI_DEVICE_ID_VIA_VX855: + case PCI_DEVICE_ID_VIA_VX900: + case PCI_DEVICE_ID_VIA_8251: + case PCI_DEVICE_ID_VIA_8237: + case PCI_DEVICE_ID_VIA_8237A: + case PCI_DEVICE_ID_VIA_8237S: + case PCI_DEVICE_ID_VIA_8235: + case PCI_DEVICE_ID_VIA_8233A: + case PCI_DEVICE_ID_VIA_8233_0: + vt596_features |= FEATURE_I2CBLOCK; + break; + case PCI_DEVICE_ID_VIA_82C686_4: + /* The VT82C686B (rev 0x40) does support I2C block + transactions, but the VT82C686A (rev 0x30) doesn't */ + if (pdev->revision >= 0x40) + vt596_features |= FEATURE_I2CBLOCK; + break; + } + + vt596_adapter.dev.parent = &pdev->dev; + snprintf(vt596_adapter.name, sizeof(vt596_adapter.name), + "SMBus Via Pro adapter at %04x", vt596_smba); + + vt596_pdev = pci_dev_get(pdev); + error = i2c_add_adapter(&vt596_adapter); + if (error) { + pci_dev_put(vt596_pdev); + vt596_pdev = NULL; + goto release_region; + } + + /* Always return failure here. This is to allow other drivers to bind + * to this pci device. We don't really want to have control over the + * pci device, we only wanted to read as few register values from it. + */ + return -ENODEV; + +release_region: + release_region(vt596_smba, 8); + return error; +} + +static const struct pci_device_id vt596_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C596_3), + .driver_data = SMBBA1 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C596B_3), + .driver_data = SMBBA1 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C686_4), + .driver_data = SMBBA1 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8233_0), + .driver_data = SMBBA3 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8233A), + .driver_data = SMBBA3 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8235), + .driver_data = SMBBA3 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237), + .driver_data = SMBBA3 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237A), + .driver_data = SMBBA3 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237S), + .driver_data = SMBBA3 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8231_4), + .driver_data = SMBBA1 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8251), + .driver_data = SMBBA3 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_CX700), + .driver_data = SMBBA3 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VX800), + .driver_data = SMBBA3 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VX855), + .driver_data = SMBBA3 }, + { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VX900), + .driver_data = SMBBA3 }, + { 0, } +}; + +MODULE_DEVICE_TABLE(pci, vt596_ids); + +static struct pci_driver vt596_driver = { + .name = "vt596_smbus", + .id_table = vt596_ids, + .probe = vt596_probe, +}; + +static int __init i2c_vt596_init(void) +{ + return pci_register_driver(&vt596_driver); +} + + +static void __exit i2c_vt596_exit(void) +{ + pci_unregister_driver(&vt596_driver); + if (vt596_pdev != NULL) { + i2c_del_adapter(&vt596_adapter); + release_region(vt596_smba, 8); + pci_dev_put(vt596_pdev); + vt596_pdev = NULL; + } +} + +MODULE_AUTHOR("Kyosti Malkki <kmalkki@cc.hut.fi>"); +MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>"); +MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>"); +MODULE_DESCRIPTION("vt82c596 SMBus driver"); +MODULE_LICENSE("GPL"); + +module_init(i2c_vt596_init); +module_exit(i2c_vt596_exit); diff --git a/drivers/i2c/busses/i2c-viperboard.c b/drivers/i2c/busses/i2c-viperboard.c new file mode 100644 index 000000000..9e153b5b0 --- /dev/null +++ b/drivers/i2c/busses/i2c-viperboard.c @@ -0,0 +1,466 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Nano River Technologies viperboard i2c master driver + * + * (C) 2012 by Lemonage GmbH + * Author: Lars Poeschel <poeschel@lemonage.de> + * All rights reserved. + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/mutex.h> +#include <linux/platform_device.h> + +#include <linux/usb.h> +#include <linux/i2c.h> + +#include <linux/mfd/viperboard.h> + +struct vprbrd_i2c { + struct i2c_adapter i2c; + u8 bus_freq_param; +}; + +/* i2c bus frequency module parameter */ +static u8 i2c_bus_param; +static unsigned int i2c_bus_freq = 100; +module_param(i2c_bus_freq, int, 0); +MODULE_PARM_DESC(i2c_bus_freq, + "i2c bus frequency in khz (default is 100) valid values: 10, 100, 200, 400, 1000, 3000, 6000"); + +static int vprbrd_i2c_status(struct i2c_adapter *i2c, + struct vprbrd_i2c_status *status, bool prev_error) +{ + u16 bytes_xfer; + int ret; + struct vprbrd *vb = (struct vprbrd *)i2c->algo_data; + + /* check for protocol error */ + bytes_xfer = sizeof(struct vprbrd_i2c_status); + + ret = usb_control_msg(vb->usb_dev, usb_rcvctrlpipe(vb->usb_dev, 0), + VPRBRD_USB_REQUEST_I2C, VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, + status, bytes_xfer, VPRBRD_USB_TIMEOUT_MS); + + if (ret != bytes_xfer) + prev_error = true; + + if (prev_error) { + dev_err(&i2c->dev, "failure in usb communication\n"); + return -EREMOTEIO; + } + + dev_dbg(&i2c->dev, " status = %d\n", status->status); + if (status->status != 0x00) { + dev_err(&i2c->dev, "failure: i2c protocol error\n"); + return -EPROTO; + } + return 0; +} + +static int vprbrd_i2c_receive(struct usb_device *usb_dev, + struct vprbrd_i2c_read_msg *rmsg, int bytes_xfer) +{ + int ret, bytes_actual; + int error = 0; + + /* send the read request */ + ret = usb_bulk_msg(usb_dev, + usb_sndbulkpipe(usb_dev, VPRBRD_EP_OUT), rmsg, + sizeof(struct vprbrd_i2c_read_hdr), &bytes_actual, + VPRBRD_USB_TIMEOUT_MS); + + if ((ret < 0) + || (bytes_actual != sizeof(struct vprbrd_i2c_read_hdr))) { + dev_err(&usb_dev->dev, "failure transmitting usb\n"); + error = -EREMOTEIO; + } + + /* read the actual data */ + ret = usb_bulk_msg(usb_dev, + usb_rcvbulkpipe(usb_dev, VPRBRD_EP_IN), rmsg, + bytes_xfer, &bytes_actual, VPRBRD_USB_TIMEOUT_MS); + + if ((ret < 0) || (bytes_xfer != bytes_actual)) { + dev_err(&usb_dev->dev, "failure receiving usb\n"); + error = -EREMOTEIO; + } + return error; +} + +static int vprbrd_i2c_addr(struct usb_device *usb_dev, + struct vprbrd_i2c_addr_msg *amsg) +{ + int ret, bytes_actual; + + ret = usb_bulk_msg(usb_dev, + usb_sndbulkpipe(usb_dev, VPRBRD_EP_OUT), amsg, + sizeof(struct vprbrd_i2c_addr_msg), &bytes_actual, + VPRBRD_USB_TIMEOUT_MS); + + if ((ret < 0) || + (sizeof(struct vprbrd_i2c_addr_msg) != bytes_actual)) { + dev_err(&usb_dev->dev, "failure transmitting usb\n"); + return -EREMOTEIO; + } + return 0; +} + +static int vprbrd_i2c_read(struct vprbrd *vb, struct i2c_msg *msg) +{ + int ret; + u16 remain_len, len1, len2, start = 0x0000; + struct vprbrd_i2c_read_msg *rmsg = + (struct vprbrd_i2c_read_msg *)vb->buf; + + remain_len = msg->len; + rmsg->header.cmd = VPRBRD_I2C_CMD_READ; + while (remain_len > 0) { + rmsg->header.addr = cpu_to_le16(start + 0x4000); + if (remain_len <= 255) { + len1 = remain_len; + len2 = 0x00; + rmsg->header.len0 = remain_len; + rmsg->header.len1 = 0x00; + rmsg->header.len2 = 0x00; + rmsg->header.len3 = 0x00; + rmsg->header.len4 = 0x00; + rmsg->header.len5 = 0x00; + remain_len = 0; + } else if (remain_len <= 510) { + len1 = remain_len; + len2 = 0x00; + rmsg->header.len0 = remain_len - 255; + rmsg->header.len1 = 0xff; + rmsg->header.len2 = 0x00; + rmsg->header.len3 = 0x00; + rmsg->header.len4 = 0x00; + rmsg->header.len5 = 0x00; + remain_len = 0; + } else if (remain_len <= 512) { + len1 = remain_len; + len2 = 0x00; + rmsg->header.len0 = remain_len - 510; + rmsg->header.len1 = 0xff; + rmsg->header.len2 = 0xff; + rmsg->header.len3 = 0x00; + rmsg->header.len4 = 0x00; + rmsg->header.len5 = 0x00; + remain_len = 0; + } else if (remain_len <= 767) { + len1 = 512; + len2 = remain_len - 512; + rmsg->header.len0 = 0x02; + rmsg->header.len1 = 0xff; + rmsg->header.len2 = 0xff; + rmsg->header.len3 = remain_len - 512; + rmsg->header.len4 = 0x00; + rmsg->header.len5 = 0x00; + remain_len = 0; + } else if (remain_len <= 1022) { + len1 = 512; + len2 = remain_len - 512; + rmsg->header.len0 = 0x02; + rmsg->header.len1 = 0xff; + rmsg->header.len2 = 0xff; + rmsg->header.len3 = remain_len - 767; + rmsg->header.len4 = 0xff; + rmsg->header.len5 = 0x00; + remain_len = 0; + } else if (remain_len <= 1024) { + len1 = 512; + len2 = remain_len - 512; + rmsg->header.len0 = 0x02; + rmsg->header.len1 = 0xff; + rmsg->header.len2 = 0xff; + rmsg->header.len3 = remain_len - 1022; + rmsg->header.len4 = 0xff; + rmsg->header.len5 = 0xff; + remain_len = 0; + } else { + len1 = 512; + len2 = 512; + rmsg->header.len0 = 0x02; + rmsg->header.len1 = 0xff; + rmsg->header.len2 = 0xff; + rmsg->header.len3 = 0x02; + rmsg->header.len4 = 0xff; + rmsg->header.len5 = 0xff; + remain_len -= 1024; + start += 1024; + } + rmsg->header.tf1 = cpu_to_le16(len1); + rmsg->header.tf2 = cpu_to_le16(len2); + + /* first read transfer */ + ret = vprbrd_i2c_receive(vb->usb_dev, rmsg, len1); + if (ret < 0) + return ret; + /* copy the received data */ + memcpy(msg->buf + start, rmsg, len1); + + /* second read transfer if neccessary */ + if (len2 > 0) { + ret = vprbrd_i2c_receive(vb->usb_dev, rmsg, len2); + if (ret < 0) + return ret; + /* copy the received data */ + memcpy(msg->buf + start + 512, rmsg, len2); + } + } + return 0; +} + +static int vprbrd_i2c_write(struct vprbrd *vb, struct i2c_msg *msg) +{ + int ret, bytes_actual; + u16 remain_len, bytes_xfer, + start = 0x0000; + struct vprbrd_i2c_write_msg *wmsg = + (struct vprbrd_i2c_write_msg *)vb->buf; + + remain_len = msg->len; + wmsg->header.cmd = VPRBRD_I2C_CMD_WRITE; + wmsg->header.last = 0x00; + wmsg->header.chan = 0x00; + wmsg->header.spi = 0x0000; + while (remain_len > 0) { + wmsg->header.addr = cpu_to_le16(start + 0x4000); + if (remain_len > 503) { + wmsg->header.len1 = 0xff; + wmsg->header.len2 = 0xf8; + remain_len -= 503; + bytes_xfer = 503 + sizeof(struct vprbrd_i2c_write_hdr); + start += 503; + } else if (remain_len > 255) { + wmsg->header.len1 = 0xff; + wmsg->header.len2 = (remain_len - 255); + bytes_xfer = remain_len + + sizeof(struct vprbrd_i2c_write_hdr); + remain_len = 0; + } else { + wmsg->header.len1 = remain_len; + wmsg->header.len2 = 0x00; + bytes_xfer = remain_len + + sizeof(struct vprbrd_i2c_write_hdr); + remain_len = 0; + } + memcpy(wmsg->data, msg->buf + start, + bytes_xfer - sizeof(struct vprbrd_i2c_write_hdr)); + + ret = usb_bulk_msg(vb->usb_dev, + usb_sndbulkpipe(vb->usb_dev, + VPRBRD_EP_OUT), wmsg, + bytes_xfer, &bytes_actual, VPRBRD_USB_TIMEOUT_MS); + if ((ret < 0) || (bytes_xfer != bytes_actual)) + return -EREMOTEIO; + } + return 0; +} + +static int vprbrd_i2c_xfer(struct i2c_adapter *i2c, struct i2c_msg *msgs, + int num) +{ + struct i2c_msg *pmsg; + int i, ret, + error = 0; + struct vprbrd *vb = (struct vprbrd *)i2c->algo_data; + struct vprbrd_i2c_addr_msg *amsg = + (struct vprbrd_i2c_addr_msg *)vb->buf; + struct vprbrd_i2c_status *smsg = (struct vprbrd_i2c_status *)vb->buf; + + dev_dbg(&i2c->dev, "master xfer %d messages:\n", num); + + for (i = 0 ; i < num ; i++) { + pmsg = &msgs[i]; + + dev_dbg(&i2c->dev, + " %d: %s (flags %d) %d bytes to 0x%02x\n", + i, pmsg->flags & I2C_M_RD ? "read" : "write", + pmsg->flags, pmsg->len, pmsg->addr); + + mutex_lock(&vb->lock); + /* directly send the message */ + if (pmsg->flags & I2C_M_RD) { + /* read data */ + amsg->cmd = VPRBRD_I2C_CMD_ADDR; + amsg->unknown2 = 0x00; + amsg->unknown3 = 0x00; + amsg->addr = pmsg->addr; + amsg->unknown1 = 0x01; + amsg->len = cpu_to_le16(pmsg->len); + /* send the addr and len, we're interested to board */ + ret = vprbrd_i2c_addr(vb->usb_dev, amsg); + if (ret < 0) + error = ret; + + ret = vprbrd_i2c_read(vb, pmsg); + if (ret < 0) + error = ret; + + ret = vprbrd_i2c_status(i2c, smsg, error); + if (ret < 0) + error = ret; + /* in case of protocol error, return the error */ + if (error < 0) + goto error; + } else { + /* write data */ + ret = vprbrd_i2c_write(vb, pmsg); + + amsg->cmd = VPRBRD_I2C_CMD_ADDR; + amsg->unknown2 = 0x00; + amsg->unknown3 = 0x00; + amsg->addr = pmsg->addr; + amsg->unknown1 = 0x00; + amsg->len = cpu_to_le16(pmsg->len); + /* send the addr, the data goes to to board */ + ret = vprbrd_i2c_addr(vb->usb_dev, amsg); + if (ret < 0) + error = ret; + + ret = vprbrd_i2c_status(i2c, smsg, error); + if (ret < 0) + error = ret; + + if (error < 0) + goto error; + } + mutex_unlock(&vb->lock); + } + return num; +error: + mutex_unlock(&vb->lock); + return error; +} + +static u32 vprbrd_i2c_func(struct i2c_adapter *i2c) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +/* This is the actual algorithm we define */ +static const struct i2c_algorithm vprbrd_algorithm = { + .master_xfer = vprbrd_i2c_xfer, + .functionality = vprbrd_i2c_func, +}; + +static const struct i2c_adapter_quirks vprbrd_quirks = { + .max_read_len = 2048, + .max_write_len = 2048, +}; + +static int vprbrd_i2c_probe(struct platform_device *pdev) +{ + struct vprbrd *vb = dev_get_drvdata(pdev->dev.parent); + struct vprbrd_i2c *vb_i2c; + int ret; + int pipe; + + vb_i2c = devm_kzalloc(&pdev->dev, sizeof(*vb_i2c), GFP_KERNEL); + if (vb_i2c == NULL) + return -ENOMEM; + + /* setup i2c adapter description */ + vb_i2c->i2c.owner = THIS_MODULE; + vb_i2c->i2c.class = I2C_CLASS_HWMON; + vb_i2c->i2c.algo = &vprbrd_algorithm; + vb_i2c->i2c.quirks = &vprbrd_quirks; + vb_i2c->i2c.algo_data = vb; + /* save the param in usb capabable memory */ + vb_i2c->bus_freq_param = i2c_bus_param; + + snprintf(vb_i2c->i2c.name, sizeof(vb_i2c->i2c.name), + "viperboard at bus %03d device %03d", + vb->usb_dev->bus->busnum, vb->usb_dev->devnum); + + /* setting the bus frequency */ + if ((i2c_bus_param <= VPRBRD_I2C_FREQ_10KHZ) + && (i2c_bus_param >= VPRBRD_I2C_FREQ_6MHZ)) { + pipe = usb_sndctrlpipe(vb->usb_dev, 0); + ret = usb_control_msg(vb->usb_dev, pipe, + VPRBRD_USB_REQUEST_I2C_FREQ, VPRBRD_USB_TYPE_OUT, + 0x0000, 0x0000, &vb_i2c->bus_freq_param, 1, + VPRBRD_USB_TIMEOUT_MS); + if (ret != 1) { + dev_err(&pdev->dev, "failure setting i2c_bus_freq to %d\n", + i2c_bus_freq); + return -EIO; + } + } else { + dev_err(&pdev->dev, + "invalid i2c_bus_freq setting:%d\n", i2c_bus_freq); + return -EIO; + } + + vb_i2c->i2c.dev.parent = &pdev->dev; + + /* attach to i2c layer */ + i2c_add_adapter(&vb_i2c->i2c); + + platform_set_drvdata(pdev, vb_i2c); + + return 0; +} + +static void vprbrd_i2c_remove(struct platform_device *pdev) +{ + struct vprbrd_i2c *vb_i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&vb_i2c->i2c); +} + +static struct platform_driver vprbrd_i2c_driver = { + .driver.name = "viperboard-i2c", + .driver.owner = THIS_MODULE, + .probe = vprbrd_i2c_probe, + .remove_new = vprbrd_i2c_remove, +}; + +static int __init vprbrd_i2c_init(void) +{ + switch (i2c_bus_freq) { + case 6000: + i2c_bus_param = VPRBRD_I2C_FREQ_6MHZ; + break; + case 3000: + i2c_bus_param = VPRBRD_I2C_FREQ_3MHZ; + break; + case 1000: + i2c_bus_param = VPRBRD_I2C_FREQ_1MHZ; + break; + case 400: + i2c_bus_param = VPRBRD_I2C_FREQ_400KHZ; + break; + case 200: + i2c_bus_param = VPRBRD_I2C_FREQ_200KHZ; + break; + case 100: + i2c_bus_param = VPRBRD_I2C_FREQ_100KHZ; + break; + case 10: + i2c_bus_param = VPRBRD_I2C_FREQ_10KHZ; + break; + default: + pr_warn("invalid i2c_bus_freq (%d)\n", i2c_bus_freq); + i2c_bus_param = VPRBRD_I2C_FREQ_100KHZ; + } + + return platform_driver_register(&vprbrd_i2c_driver); +} +subsys_initcall(vprbrd_i2c_init); + +static void __exit vprbrd_i2c_exit(void) +{ + platform_driver_unregister(&vprbrd_i2c_driver); +} +module_exit(vprbrd_i2c_exit); + +MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>"); +MODULE_DESCRIPTION("I2C master driver for Nano River Techs Viperboard"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:viperboard-i2c"); diff --git a/drivers/i2c/busses/i2c-virtio.c b/drivers/i2c/busses/i2c-virtio.c new file mode 100644 index 000000000..c60ae531b --- /dev/null +++ b/drivers/i2c/busses/i2c-virtio.c @@ -0,0 +1,278 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Virtio I2C Bus Driver + * + * The Virtio I2C Specification: + * https://raw.githubusercontent.com/oasis-tcs/virtio-spec/master/virtio-i2c.tex + * + * Copyright (c) 2021 Intel Corporation. All rights reserved. + */ + +#include <linux/acpi.h> +#include <linux/completion.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/virtio.h> +#include <linux/virtio_ids.h> +#include <linux/virtio_config.h> +#include <linux/virtio_i2c.h> + +/** + * struct virtio_i2c - virtio I2C data + * @vdev: virtio device for this controller + * @adap: I2C adapter for this controller + * @vq: the virtio virtqueue for communication + */ +struct virtio_i2c { + struct virtio_device *vdev; + struct i2c_adapter adap; + struct virtqueue *vq; +}; + +/** + * struct virtio_i2c_req - the virtio I2C request structure + * @completion: completion of virtio I2C message + * @out_hdr: the OUT header of the virtio I2C message + * @buf: the buffer into which data is read, or from which it's written + * @in_hdr: the IN header of the virtio I2C message + */ +struct virtio_i2c_req { + struct completion completion; + struct virtio_i2c_out_hdr out_hdr ____cacheline_aligned; + uint8_t *buf ____cacheline_aligned; + struct virtio_i2c_in_hdr in_hdr ____cacheline_aligned; +}; + +static void virtio_i2c_msg_done(struct virtqueue *vq) +{ + struct virtio_i2c_req *req; + unsigned int len; + + while ((req = virtqueue_get_buf(vq, &len))) + complete(&req->completion); +} + +static int virtio_i2c_prepare_reqs(struct virtqueue *vq, + struct virtio_i2c_req *reqs, + struct i2c_msg *msgs, int num) +{ + struct scatterlist *sgs[3], out_hdr, msg_buf, in_hdr; + int i; + + for (i = 0; i < num; i++) { + int outcnt = 0, incnt = 0; + + init_completion(&reqs[i].completion); + + /* + * Only 7-bit mode supported for this moment. For the address + * format, Please check the Virtio I2C Specification. + */ + reqs[i].out_hdr.addr = cpu_to_le16(msgs[i].addr << 1); + + if (msgs[i].flags & I2C_M_RD) + reqs[i].out_hdr.flags |= cpu_to_le32(VIRTIO_I2C_FLAGS_M_RD); + + if (i != num - 1) + reqs[i].out_hdr.flags |= cpu_to_le32(VIRTIO_I2C_FLAGS_FAIL_NEXT); + + sg_init_one(&out_hdr, &reqs[i].out_hdr, sizeof(reqs[i].out_hdr)); + sgs[outcnt++] = &out_hdr; + + if (msgs[i].len) { + reqs[i].buf = i2c_get_dma_safe_msg_buf(&msgs[i], 1); + if (!reqs[i].buf) + break; + + sg_init_one(&msg_buf, reqs[i].buf, msgs[i].len); + + if (msgs[i].flags & I2C_M_RD) + sgs[outcnt + incnt++] = &msg_buf; + else + sgs[outcnt++] = &msg_buf; + } + + sg_init_one(&in_hdr, &reqs[i].in_hdr, sizeof(reqs[i].in_hdr)); + sgs[outcnt + incnt++] = &in_hdr; + + if (virtqueue_add_sgs(vq, sgs, outcnt, incnt, &reqs[i], GFP_KERNEL)) { + i2c_put_dma_safe_msg_buf(reqs[i].buf, &msgs[i], false); + break; + } + } + + return i; +} + +static int virtio_i2c_complete_reqs(struct virtqueue *vq, + struct virtio_i2c_req *reqs, + struct i2c_msg *msgs, int num) +{ + bool failed = false; + int i, j = 0; + + for (i = 0; i < num; i++) { + struct virtio_i2c_req *req = &reqs[i]; + + wait_for_completion(&req->completion); + + if (!failed && req->in_hdr.status != VIRTIO_I2C_MSG_OK) + failed = true; + + i2c_put_dma_safe_msg_buf(reqs[i].buf, &msgs[i], !failed); + + if (!failed) + j++; + } + + return j; +} + +static int virtio_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct virtio_i2c *vi = i2c_get_adapdata(adap); + struct virtqueue *vq = vi->vq; + struct virtio_i2c_req *reqs; + int count; + + reqs = kcalloc(num, sizeof(*reqs), GFP_KERNEL); + if (!reqs) + return -ENOMEM; + + count = virtio_i2c_prepare_reqs(vq, reqs, msgs, num); + if (!count) + goto err_free; + + /* + * For the case where count < num, i.e. we weren't able to queue all the + * msgs, ideally we should abort right away and return early, but some + * of the messages are already sent to the remote I2C controller and the + * virtqueue will be left in undefined state in that case. We kick the + * remote here to clear the virtqueue, so we can try another set of + * messages later on. + */ + virtqueue_kick(vq); + + count = virtio_i2c_complete_reqs(vq, reqs, msgs, count); + +err_free: + kfree(reqs); + return count; +} + +static void virtio_i2c_del_vqs(struct virtio_device *vdev) +{ + virtio_reset_device(vdev); + vdev->config->del_vqs(vdev); +} + +static int virtio_i2c_setup_vqs(struct virtio_i2c *vi) +{ + struct virtio_device *vdev = vi->vdev; + + vi->vq = virtio_find_single_vq(vdev, virtio_i2c_msg_done, "msg"); + return PTR_ERR_OR_ZERO(vi->vq); +} + +static u32 virtio_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static struct i2c_algorithm virtio_algorithm = { + .master_xfer = virtio_i2c_xfer, + .functionality = virtio_i2c_func, +}; + +static int virtio_i2c_probe(struct virtio_device *vdev) +{ + struct virtio_i2c *vi; + int ret; + + if (!virtio_has_feature(vdev, VIRTIO_I2C_F_ZERO_LENGTH_REQUEST)) { + dev_err(&vdev->dev, "Zero-length request feature is mandatory\n"); + return -EINVAL; + } + + vi = devm_kzalloc(&vdev->dev, sizeof(*vi), GFP_KERNEL); + if (!vi) + return -ENOMEM; + + vdev->priv = vi; + vi->vdev = vdev; + + ret = virtio_i2c_setup_vqs(vi); + if (ret) + return ret; + + vi->adap.owner = THIS_MODULE; + snprintf(vi->adap.name, sizeof(vi->adap.name), + "i2c_virtio at virtio bus %d", vdev->index); + vi->adap.algo = &virtio_algorithm; + vi->adap.dev.parent = &vdev->dev; + vi->adap.dev.of_node = vdev->dev.of_node; + i2c_set_adapdata(&vi->adap, vi); + + /* + * Setup ACPI node for controlled devices which will be probed through + * ACPI. + */ + ACPI_COMPANION_SET(&vi->adap.dev, ACPI_COMPANION(vdev->dev.parent)); + + ret = i2c_add_adapter(&vi->adap); + if (ret) + virtio_i2c_del_vqs(vdev); + + return ret; +} + +static void virtio_i2c_remove(struct virtio_device *vdev) +{ + struct virtio_i2c *vi = vdev->priv; + + i2c_del_adapter(&vi->adap); + virtio_i2c_del_vqs(vdev); +} + +static struct virtio_device_id id_table[] = { + { VIRTIO_ID_I2C_ADAPTER, VIRTIO_DEV_ANY_ID }, + {} +}; +MODULE_DEVICE_TABLE(virtio, id_table); + +static int virtio_i2c_freeze(struct virtio_device *vdev) +{ + virtio_i2c_del_vqs(vdev); + return 0; +} + +static int virtio_i2c_restore(struct virtio_device *vdev) +{ + return virtio_i2c_setup_vqs(vdev->priv); +} + +static const unsigned int features[] = { + VIRTIO_I2C_F_ZERO_LENGTH_REQUEST, +}; + +static struct virtio_driver virtio_i2c_driver = { + .feature_table = features, + .feature_table_size = ARRAY_SIZE(features), + .id_table = id_table, + .probe = virtio_i2c_probe, + .remove = virtio_i2c_remove, + .driver = { + .name = "i2c_virtio", + }, + .freeze = pm_sleep_ptr(virtio_i2c_freeze), + .restore = pm_sleep_ptr(virtio_i2c_restore), +}; +module_virtio_driver(virtio_i2c_driver); + +MODULE_AUTHOR("Jie Deng <jie.deng@intel.com>"); +MODULE_AUTHOR("Conghui Chen <conghui.chen@intel.com>"); +MODULE_DESCRIPTION("Virtio i2c bus driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-wmt.c b/drivers/i2c/busses/i2c-wmt.c new file mode 100644 index 000000000..76118abc6 --- /dev/null +++ b/drivers/i2c/busses/i2c-wmt.c @@ -0,0 +1,466 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Wondermedia I2C Master Mode Driver + * + * Copyright (C) 2012 Tony Prisk <linux@prisktech.co.nz> + * + * Derived from GPLv2+ licensed source: + * - Copyright (C) 2008 WonderMedia Technologies, Inc. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> + +#define REG_CR 0x00 +#define REG_TCR 0x02 +#define REG_CSR 0x04 +#define REG_ISR 0x06 +#define REG_IMR 0x08 +#define REG_CDR 0x0A +#define REG_TR 0x0C +#define REG_MCR 0x0E +#define REG_SLAVE_CR 0x10 +#define REG_SLAVE_SR 0x12 +#define REG_SLAVE_ISR 0x14 +#define REG_SLAVE_IMR 0x16 +#define REG_SLAVE_DR 0x18 +#define REG_SLAVE_TR 0x1A + +/* REG_CR Bit fields */ +#define CR_TX_NEXT_ACK 0x0000 +#define CR_ENABLE 0x0001 +#define CR_TX_NEXT_NO_ACK 0x0002 +#define CR_TX_END 0x0004 +#define CR_CPU_RDY 0x0008 +#define SLAV_MODE_SEL 0x8000 + +/* REG_TCR Bit fields */ +#define TCR_STANDARD_MODE 0x0000 +#define TCR_MASTER_WRITE 0x0000 +#define TCR_HS_MODE 0x2000 +#define TCR_MASTER_READ 0x4000 +#define TCR_FAST_MODE 0x8000 +#define TCR_SLAVE_ADDR_MASK 0x007F + +/* REG_ISR Bit fields */ +#define ISR_NACK_ADDR 0x0001 +#define ISR_BYTE_END 0x0002 +#define ISR_SCL_TIMEOUT 0x0004 +#define ISR_WRITE_ALL 0x0007 + +/* REG_IMR Bit fields */ +#define IMR_ENABLE_ALL 0x0007 + +/* REG_CSR Bit fields */ +#define CSR_RCV_NOT_ACK 0x0001 +#define CSR_RCV_ACK_MASK 0x0001 +#define CSR_READY_MASK 0x0002 + +/* REG_TR */ +#define SCL_TIMEOUT(x) (((x) & 0xFF) << 8) +#define TR_STD 0x0064 +#define TR_HS 0x0019 + +/* REG_MCR */ +#define MCR_APB_96M 7 +#define MCR_APB_166M 12 + +#define I2C_MODE_STANDARD 0 +#define I2C_MODE_FAST 1 + +#define WMT_I2C_TIMEOUT (msecs_to_jiffies(1000)) + +struct wmt_i2c_dev { + struct i2c_adapter adapter; + struct completion complete; + struct device *dev; + void __iomem *base; + struct clk *clk; + int mode; + int irq; + u16 cmd_status; +}; + +static int wmt_i2c_wait_bus_not_busy(struct wmt_i2c_dev *i2c_dev) +{ + unsigned long timeout; + + timeout = jiffies + WMT_I2C_TIMEOUT; + while (!(readw(i2c_dev->base + REG_CSR) & CSR_READY_MASK)) { + if (time_after(jiffies, timeout)) { + dev_warn(i2c_dev->dev, "timeout waiting for bus ready\n"); + return -EBUSY; + } + msleep(20); + } + + return 0; +} + +static int wmt_check_status(struct wmt_i2c_dev *i2c_dev) +{ + int ret = 0; + + if (i2c_dev->cmd_status & ISR_NACK_ADDR) + ret = -EIO; + + if (i2c_dev->cmd_status & ISR_SCL_TIMEOUT) + ret = -ETIMEDOUT; + + return ret; +} + +static int wmt_i2c_write(struct i2c_adapter *adap, struct i2c_msg *pmsg, + int last) +{ + struct wmt_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + u16 val, tcr_val; + int ret; + unsigned long wait_result; + int xfer_len = 0; + + if (!(pmsg->flags & I2C_M_NOSTART)) { + ret = wmt_i2c_wait_bus_not_busy(i2c_dev); + if (ret < 0) + return ret; + } + + if (pmsg->len == 0) { + /* + * We still need to run through the while (..) once, so + * start at -1 and break out early from the loop + */ + xfer_len = -1; + writew(0, i2c_dev->base + REG_CDR); + } else { + writew(pmsg->buf[0] & 0xFF, i2c_dev->base + REG_CDR); + } + + if (!(pmsg->flags & I2C_M_NOSTART)) { + val = readw(i2c_dev->base + REG_CR); + val &= ~CR_TX_END; + writew(val, i2c_dev->base + REG_CR); + + val = readw(i2c_dev->base + REG_CR); + val |= CR_CPU_RDY; + writew(val, i2c_dev->base + REG_CR); + } + + reinit_completion(&i2c_dev->complete); + + if (i2c_dev->mode == I2C_MODE_STANDARD) + tcr_val = TCR_STANDARD_MODE; + else + tcr_val = TCR_FAST_MODE; + + tcr_val |= (TCR_MASTER_WRITE | (pmsg->addr & TCR_SLAVE_ADDR_MASK)); + + writew(tcr_val, i2c_dev->base + REG_TCR); + + if (pmsg->flags & I2C_M_NOSTART) { + val = readw(i2c_dev->base + REG_CR); + val |= CR_CPU_RDY; + writew(val, i2c_dev->base + REG_CR); + } + + while (xfer_len < pmsg->len) { + wait_result = wait_for_completion_timeout(&i2c_dev->complete, + msecs_to_jiffies(500)); + + if (wait_result == 0) + return -ETIMEDOUT; + + ret = wmt_check_status(i2c_dev); + if (ret) + return ret; + + xfer_len++; + + val = readw(i2c_dev->base + REG_CSR); + if ((val & CSR_RCV_ACK_MASK) == CSR_RCV_NOT_ACK) { + dev_dbg(i2c_dev->dev, "write RCV NACK error\n"); + return -EIO; + } + + if (pmsg->len == 0) { + val = CR_TX_END | CR_CPU_RDY | CR_ENABLE; + writew(val, i2c_dev->base + REG_CR); + break; + } + + if (xfer_len == pmsg->len) { + if (last != 1) + writew(CR_ENABLE, i2c_dev->base + REG_CR); + } else { + writew(pmsg->buf[xfer_len] & 0xFF, i2c_dev->base + + REG_CDR); + writew(CR_CPU_RDY | CR_ENABLE, i2c_dev->base + REG_CR); + } + } + + return 0; +} + +static int wmt_i2c_read(struct i2c_adapter *adap, struct i2c_msg *pmsg, + int last) +{ + struct wmt_i2c_dev *i2c_dev = i2c_get_adapdata(adap); + u16 val, tcr_val; + int ret; + unsigned long wait_result; + u32 xfer_len = 0; + + if (!(pmsg->flags & I2C_M_NOSTART)) { + ret = wmt_i2c_wait_bus_not_busy(i2c_dev); + if (ret < 0) + return ret; + } + + val = readw(i2c_dev->base + REG_CR); + val &= ~CR_TX_END; + writew(val, i2c_dev->base + REG_CR); + + val = readw(i2c_dev->base + REG_CR); + val &= ~CR_TX_NEXT_NO_ACK; + writew(val, i2c_dev->base + REG_CR); + + if (!(pmsg->flags & I2C_M_NOSTART)) { + val = readw(i2c_dev->base + REG_CR); + val |= CR_CPU_RDY; + writew(val, i2c_dev->base + REG_CR); + } + + if (pmsg->len == 1) { + val = readw(i2c_dev->base + REG_CR); + val |= CR_TX_NEXT_NO_ACK; + writew(val, i2c_dev->base + REG_CR); + } + + reinit_completion(&i2c_dev->complete); + + if (i2c_dev->mode == I2C_MODE_STANDARD) + tcr_val = TCR_STANDARD_MODE; + else + tcr_val = TCR_FAST_MODE; + + tcr_val |= TCR_MASTER_READ | (pmsg->addr & TCR_SLAVE_ADDR_MASK); + + writew(tcr_val, i2c_dev->base + REG_TCR); + + if (pmsg->flags & I2C_M_NOSTART) { + val = readw(i2c_dev->base + REG_CR); + val |= CR_CPU_RDY; + writew(val, i2c_dev->base + REG_CR); + } + + while (xfer_len < pmsg->len) { + wait_result = wait_for_completion_timeout(&i2c_dev->complete, + msecs_to_jiffies(500)); + + if (!wait_result) + return -ETIMEDOUT; + + ret = wmt_check_status(i2c_dev); + if (ret) + return ret; + + pmsg->buf[xfer_len] = readw(i2c_dev->base + REG_CDR) >> 8; + xfer_len++; + + if (xfer_len == pmsg->len - 1) { + val = readw(i2c_dev->base + REG_CR); + val |= (CR_TX_NEXT_NO_ACK | CR_CPU_RDY); + writew(val, i2c_dev->base + REG_CR); + } else { + val = readw(i2c_dev->base + REG_CR); + val |= CR_CPU_RDY; + writew(val, i2c_dev->base + REG_CR); + } + } + + return 0; +} + +static int wmt_i2c_xfer(struct i2c_adapter *adap, + struct i2c_msg msgs[], + int num) +{ + struct i2c_msg *pmsg; + int i, is_last; + int ret = 0; + + for (i = 0; ret >= 0 && i < num; i++) { + is_last = ((i + 1) == num); + + pmsg = &msgs[i]; + if (pmsg->flags & I2C_M_RD) + ret = wmt_i2c_read(adap, pmsg, is_last); + else + ret = wmt_i2c_write(adap, pmsg, is_last); + } + + return (ret < 0) ? ret : i; +} + +static u32 wmt_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_NOSTART; +} + +static const struct i2c_algorithm wmt_i2c_algo = { + .master_xfer = wmt_i2c_xfer, + .functionality = wmt_i2c_func, +}; + +static irqreturn_t wmt_i2c_isr(int irq, void *data) +{ + struct wmt_i2c_dev *i2c_dev = data; + + /* save the status and write-clear it */ + i2c_dev->cmd_status = readw(i2c_dev->base + REG_ISR); + writew(i2c_dev->cmd_status, i2c_dev->base + REG_ISR); + + complete(&i2c_dev->complete); + + return IRQ_HANDLED; +} + +static int wmt_i2c_reset_hardware(struct wmt_i2c_dev *i2c_dev) +{ + int err; + + err = clk_prepare_enable(i2c_dev->clk); + if (err) { + dev_err(i2c_dev->dev, "failed to enable clock\n"); + return err; + } + + err = clk_set_rate(i2c_dev->clk, 20000000); + if (err) { + dev_err(i2c_dev->dev, "failed to set clock = 20Mhz\n"); + clk_disable_unprepare(i2c_dev->clk); + return err; + } + + writew(0, i2c_dev->base + REG_CR); + writew(MCR_APB_166M, i2c_dev->base + REG_MCR); + writew(ISR_WRITE_ALL, i2c_dev->base + REG_ISR); + writew(IMR_ENABLE_ALL, i2c_dev->base + REG_IMR); + writew(CR_ENABLE, i2c_dev->base + REG_CR); + readw(i2c_dev->base + REG_CSR); /* read clear */ + writew(ISR_WRITE_ALL, i2c_dev->base + REG_ISR); + + if (i2c_dev->mode == I2C_MODE_STANDARD) + writew(SCL_TIMEOUT(128) | TR_STD, i2c_dev->base + REG_TR); + else + writew(SCL_TIMEOUT(128) | TR_HS, i2c_dev->base + REG_TR); + + return 0; +} + +static int wmt_i2c_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct wmt_i2c_dev *i2c_dev; + struct i2c_adapter *adap; + int err; + u32 clk_rate; + + i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); + if (!i2c_dev) + return -ENOMEM; + + i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(i2c_dev->base)) + return PTR_ERR(i2c_dev->base); + + i2c_dev->irq = irq_of_parse_and_map(np, 0); + if (!i2c_dev->irq) { + dev_err(&pdev->dev, "irq missing or invalid\n"); + return -EINVAL; + } + + i2c_dev->clk = of_clk_get(np, 0); + if (IS_ERR(i2c_dev->clk)) { + dev_err(&pdev->dev, "unable to request clock\n"); + return PTR_ERR(i2c_dev->clk); + } + + i2c_dev->mode = I2C_MODE_STANDARD; + err = of_property_read_u32(np, "clock-frequency", &clk_rate); + if (!err && (clk_rate == I2C_MAX_FAST_MODE_FREQ)) + i2c_dev->mode = I2C_MODE_FAST; + + i2c_dev->dev = &pdev->dev; + + err = devm_request_irq(&pdev->dev, i2c_dev->irq, wmt_i2c_isr, 0, + "i2c", i2c_dev); + if (err) { + dev_err(&pdev->dev, "failed to request irq %i\n", i2c_dev->irq); + return err; + } + + adap = &i2c_dev->adapter; + i2c_set_adapdata(adap, i2c_dev); + strscpy(adap->name, "WMT I2C adapter", sizeof(adap->name)); + adap->owner = THIS_MODULE; + adap->algo = &wmt_i2c_algo; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + + init_completion(&i2c_dev->complete); + + err = wmt_i2c_reset_hardware(i2c_dev); + if (err) { + dev_err(&pdev->dev, "error initializing hardware\n"); + return err; + } + + err = i2c_add_adapter(adap); + if (err) + return err; + + platform_set_drvdata(pdev, i2c_dev); + + return 0; +} + +static void wmt_i2c_remove(struct platform_device *pdev) +{ + struct wmt_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + + /* Disable interrupts, clock and delete adapter */ + writew(0, i2c_dev->base + REG_IMR); + clk_disable_unprepare(i2c_dev->clk); + i2c_del_adapter(&i2c_dev->adapter); +} + +static const struct of_device_id wmt_i2c_dt_ids[] = { + { .compatible = "wm,wm8505-i2c" }, + { /* Sentinel */ }, +}; + +static struct platform_driver wmt_i2c_driver = { + .probe = wmt_i2c_probe, + .remove_new = wmt_i2c_remove, + .driver = { + .name = "wmt-i2c", + .of_match_table = wmt_i2c_dt_ids, + }, +}; + +module_platform_driver(wmt_i2c_driver); + +MODULE_DESCRIPTION("Wondermedia I2C master-mode bus adapter"); +MODULE_AUTHOR("Tony Prisk <linux@prisktech.co.nz>"); +MODULE_LICENSE("GPL"); +MODULE_DEVICE_TABLE(of, wmt_i2c_dt_ids); diff --git a/drivers/i2c/busses/i2c-xgene-slimpro.c b/drivers/i2c/busses/i2c-xgene-slimpro.c new file mode 100644 index 000000000..fbc1ffbd2 --- /dev/null +++ b/drivers/i2c/busses/i2c-xgene-slimpro.c @@ -0,0 +1,605 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * X-Gene SLIMpro I2C Driver + * + * Copyright (c) 2014, Applied Micro Circuits Corporation + * Author: Feng Kan <fkan@apm.com> + * Author: Hieu Le <hnle@apm.com> + * + * This driver provides support for X-Gene SLIMpro I2C device access + * using the APM X-Gene SLIMpro mailbox driver. + */ +#include <acpi/pcc.h> +#include <linux/acpi.h> +#include <linux/dma-mapping.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/mailbox_client.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> + +#define MAILBOX_OP_TIMEOUT 1000 /* Operation time out in ms */ +#define MAILBOX_I2C_INDEX 0 +#define SLIMPRO_IIC_BUS 1 /* Use I2C bus 1 only */ + +#define SMBUS_CMD_LEN 1 +#define BYTE_DATA 1 +#define WORD_DATA 2 +#define BLOCK_DATA 3 + +#define SLIMPRO_IIC_I2C_PROTOCOL 0 +#define SLIMPRO_IIC_SMB_PROTOCOL 1 + +#define SLIMPRO_IIC_READ 0 +#define SLIMPRO_IIC_WRITE 1 + +#define IIC_SMB_WITHOUT_DATA_LEN 0 +#define IIC_SMB_WITH_DATA_LEN 1 + +#define SLIMPRO_DEBUG_MSG 0 +#define SLIMPRO_MSG_TYPE_SHIFT 28 +#define SLIMPRO_DBG_SUBTYPE_I2C1READ 4 +#define SLIMPRO_DBGMSG_TYPE_SHIFT 24 +#define SLIMPRO_DBGMSG_TYPE_MASK 0x0F000000U +#define SLIMPRO_IIC_DEV_SHIFT 23 +#define SLIMPRO_IIC_DEV_MASK 0x00800000U +#define SLIMPRO_IIC_DEVID_SHIFT 13 +#define SLIMPRO_IIC_DEVID_MASK 0x007FE000U +#define SLIMPRO_IIC_RW_SHIFT 12 +#define SLIMPRO_IIC_RW_MASK 0x00001000U +#define SLIMPRO_IIC_PROTO_SHIFT 11 +#define SLIMPRO_IIC_PROTO_MASK 0x00000800U +#define SLIMPRO_IIC_ADDRLEN_SHIFT 8 +#define SLIMPRO_IIC_ADDRLEN_MASK 0x00000700U +#define SLIMPRO_IIC_DATALEN_SHIFT 0 +#define SLIMPRO_IIC_DATALEN_MASK 0x000000FFU + +/* + * SLIMpro I2C message encode + * + * dev - Controller number (0-based) + * chip - I2C chip address + * op - SLIMPRO_IIC_READ or SLIMPRO_IIC_WRITE + * proto - SLIMPRO_IIC_SMB_PROTOCOL or SLIMPRO_IIC_I2C_PROTOCOL + * addrlen - Length of the address field + * datalen - Length of the data field + */ +#define SLIMPRO_IIC_ENCODE_MSG(dev, chip, op, proto, addrlen, datalen) \ + ((SLIMPRO_DEBUG_MSG << SLIMPRO_MSG_TYPE_SHIFT) | \ + ((SLIMPRO_DBG_SUBTYPE_I2C1READ << SLIMPRO_DBGMSG_TYPE_SHIFT) & \ + SLIMPRO_DBGMSG_TYPE_MASK) | \ + ((dev << SLIMPRO_IIC_DEV_SHIFT) & SLIMPRO_IIC_DEV_MASK) | \ + ((chip << SLIMPRO_IIC_DEVID_SHIFT) & SLIMPRO_IIC_DEVID_MASK) | \ + ((op << SLIMPRO_IIC_RW_SHIFT) & SLIMPRO_IIC_RW_MASK) | \ + ((proto << SLIMPRO_IIC_PROTO_SHIFT) & SLIMPRO_IIC_PROTO_MASK) | \ + ((addrlen << SLIMPRO_IIC_ADDRLEN_SHIFT) & SLIMPRO_IIC_ADDRLEN_MASK) | \ + ((datalen << SLIMPRO_IIC_DATALEN_SHIFT) & SLIMPRO_IIC_DATALEN_MASK)) + +#define SLIMPRO_MSG_TYPE(v) (((v) & 0xF0000000) >> 28) + +/* + * Encode for upper address for block data + */ +#define SLIMPRO_IIC_ENCODE_FLAG_BUFADDR 0x80000000 +#define SLIMPRO_IIC_ENCODE_FLAG_WITH_DATA_LEN(a) ((u32) (((a) << 30) \ + & 0x40000000)) +#define SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(a) ((u32) (((a) >> 12) \ + & 0x3FF00000)) +#define SLIMPRO_IIC_ENCODE_ADDR(a) ((a) & 0x000FFFFF) + +#define SLIMPRO_IIC_MSG_DWORD_COUNT 3 + +/* PCC related defines */ +#define PCC_SIGNATURE 0x50424300 +#define PCC_STS_CMD_COMPLETE BIT(0) +#define PCC_STS_SCI_DOORBELL BIT(1) +#define PCC_STS_ERR BIT(2) +#define PCC_STS_PLAT_NOTIFY BIT(3) +#define PCC_CMD_GENERATE_DB_INT BIT(15) + +struct slimpro_i2c_dev { + struct i2c_adapter adapter; + struct device *dev; + struct mbox_chan *mbox_chan; + struct pcc_mbox_chan *pcc_chan; + struct mbox_client mbox_client; + int mbox_idx; + struct completion rd_complete; + u8 dma_buffer[I2C_SMBUS_BLOCK_MAX + 1]; /* dma_buffer[0] is used for length */ + u32 *resp_msg; + phys_addr_t comm_base_addr; + void *pcc_comm_addr; +}; + +#define to_slimpro_i2c_dev(cl) \ + container_of(cl, struct slimpro_i2c_dev, mbox_client) + +enum slimpro_i2c_version { + XGENE_SLIMPRO_I2C_V1 = 0, + XGENE_SLIMPRO_I2C_V2 = 1, +}; + +/* + * This function tests and clears a bitmask then returns its old value + */ +static u16 xgene_word_tst_and_clr(u16 *addr, u16 mask) +{ + u16 ret, val; + + val = le16_to_cpu(READ_ONCE(*addr)); + ret = val & mask; + val &= ~mask; + WRITE_ONCE(*addr, cpu_to_le16(val)); + + return ret; +} + +static void slimpro_i2c_rx_cb(struct mbox_client *cl, void *mssg) +{ + struct slimpro_i2c_dev *ctx = to_slimpro_i2c_dev(cl); + + /* + * Response message format: + * mssg[0] is the return code of the operation + * mssg[1] is the first data word + * mssg[2] is NOT used + */ + if (ctx->resp_msg) + *ctx->resp_msg = ((u32 *)mssg)[1]; + + if (ctx->mbox_client.tx_block) + complete(&ctx->rd_complete); +} + +static void slimpro_i2c_pcc_rx_cb(struct mbox_client *cl, void *msg) +{ + struct slimpro_i2c_dev *ctx = to_slimpro_i2c_dev(cl); + struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr; + + /* Check if platform sends interrupt */ + if (!xgene_word_tst_and_clr(&generic_comm_base->status, + PCC_STS_SCI_DOORBELL)) + return; + + if (xgene_word_tst_and_clr(&generic_comm_base->status, + PCC_STS_CMD_COMPLETE)) { + msg = generic_comm_base + 1; + + /* Response message msg[1] contains the return value. */ + if (ctx->resp_msg) + *ctx->resp_msg = ((u32 *)msg)[1]; + + complete(&ctx->rd_complete); + } +} + +static void slimpro_i2c_pcc_tx_prepare(struct slimpro_i2c_dev *ctx, u32 *msg) +{ + struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr; + u32 *ptr = (void *)(generic_comm_base + 1); + u16 status; + int i; + + WRITE_ONCE(generic_comm_base->signature, + cpu_to_le32(PCC_SIGNATURE | ctx->mbox_idx)); + + WRITE_ONCE(generic_comm_base->command, + cpu_to_le16(SLIMPRO_MSG_TYPE(msg[0]) | PCC_CMD_GENERATE_DB_INT)); + + status = le16_to_cpu(READ_ONCE(generic_comm_base->status)); + status &= ~PCC_STS_CMD_COMPLETE; + WRITE_ONCE(generic_comm_base->status, cpu_to_le16(status)); + + /* Copy the message to the PCC comm space */ + for (i = 0; i < SLIMPRO_IIC_MSG_DWORD_COUNT; i++) + WRITE_ONCE(ptr[i], cpu_to_le32(msg[i])); +} + +static int start_i2c_msg_xfer(struct slimpro_i2c_dev *ctx) +{ + if (ctx->mbox_client.tx_block || !acpi_disabled) { + if (!wait_for_completion_timeout(&ctx->rd_complete, + msecs_to_jiffies(MAILBOX_OP_TIMEOUT))) + return -ETIMEDOUT; + } + + /* Check of invalid data or no device */ + if (*ctx->resp_msg == 0xffffffff) + return -ENODEV; + + return 0; +} + +static int slimpro_i2c_send_msg(struct slimpro_i2c_dev *ctx, + u32 *msg, + u32 *data) +{ + int rc; + + ctx->resp_msg = data; + + if (!acpi_disabled) { + reinit_completion(&ctx->rd_complete); + slimpro_i2c_pcc_tx_prepare(ctx, msg); + } + + rc = mbox_send_message(ctx->mbox_chan, msg); + if (rc < 0) + goto err; + + rc = start_i2c_msg_xfer(ctx); + +err: + if (!acpi_disabled) + mbox_chan_txdone(ctx->mbox_chan, 0); + + ctx->resp_msg = NULL; + + return rc; +} + +static int slimpro_i2c_rd(struct slimpro_i2c_dev *ctx, u32 chip, + u32 addr, u32 addrlen, u32 protocol, + u32 readlen, u32 *data) +{ + u32 msg[3]; + + msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, + SLIMPRO_IIC_READ, protocol, addrlen, readlen); + msg[1] = SLIMPRO_IIC_ENCODE_ADDR(addr); + msg[2] = 0; + + return slimpro_i2c_send_msg(ctx, msg, data); +} + +static int slimpro_i2c_wr(struct slimpro_i2c_dev *ctx, u32 chip, + u32 addr, u32 addrlen, u32 protocol, u32 writelen, + u32 data) +{ + u32 msg[3]; + + msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, + SLIMPRO_IIC_WRITE, protocol, addrlen, writelen); + msg[1] = SLIMPRO_IIC_ENCODE_ADDR(addr); + msg[2] = data; + + return slimpro_i2c_send_msg(ctx, msg, msg); +} + +static int slimpro_i2c_blkrd(struct slimpro_i2c_dev *ctx, u32 chip, u32 addr, + u32 addrlen, u32 protocol, u32 readlen, + u32 with_data_len, void *data) +{ + dma_addr_t paddr; + u32 msg[3]; + int rc; + + paddr = dma_map_single(ctx->dev, ctx->dma_buffer, readlen, DMA_FROM_DEVICE); + if (dma_mapping_error(ctx->dev, paddr)) { + dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n", + ctx->dma_buffer); + return -ENOMEM; + } + + msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_READ, + protocol, addrlen, readlen); + msg[1] = SLIMPRO_IIC_ENCODE_FLAG_BUFADDR | + SLIMPRO_IIC_ENCODE_FLAG_WITH_DATA_LEN(with_data_len) | + SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(paddr) | + SLIMPRO_IIC_ENCODE_ADDR(addr); + msg[2] = (u32)paddr; + + rc = slimpro_i2c_send_msg(ctx, msg, msg); + + /* Copy to destination */ + memcpy(data, ctx->dma_buffer, readlen); + + dma_unmap_single(ctx->dev, paddr, readlen, DMA_FROM_DEVICE); + return rc; +} + +static int slimpro_i2c_blkwr(struct slimpro_i2c_dev *ctx, u32 chip, + u32 addr, u32 addrlen, u32 protocol, u32 writelen, + void *data) +{ + dma_addr_t paddr; + u32 msg[3]; + int rc; + + if (writelen > I2C_SMBUS_BLOCK_MAX) + return -EINVAL; + + memcpy(ctx->dma_buffer, data, writelen); + paddr = dma_map_single(ctx->dev, ctx->dma_buffer, writelen, + DMA_TO_DEVICE); + if (dma_mapping_error(ctx->dev, paddr)) { + dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n", + ctx->dma_buffer); + return -ENOMEM; + } + + msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_WRITE, + protocol, addrlen, writelen); + msg[1] = SLIMPRO_IIC_ENCODE_FLAG_BUFADDR | + SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(paddr) | + SLIMPRO_IIC_ENCODE_ADDR(addr); + msg[2] = (u32)paddr; + + if (ctx->mbox_client.tx_block) + reinit_completion(&ctx->rd_complete); + + rc = slimpro_i2c_send_msg(ctx, msg, msg); + + dma_unmap_single(ctx->dev, paddr, writelen, DMA_TO_DEVICE); + return rc; +} + +static int xgene_slimpro_i2c_xfer(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + struct slimpro_i2c_dev *ctx = i2c_get_adapdata(adap); + int ret = -EOPNOTSUPP; + u32 val; + + switch (size) { + case I2C_SMBUS_BYTE: + if (read_write == I2C_SMBUS_READ) { + ret = slimpro_i2c_rd(ctx, addr, 0, 0, + SLIMPRO_IIC_SMB_PROTOCOL, + BYTE_DATA, &val); + data->byte = val; + } else { + ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + 0, 0); + } + break; + case I2C_SMBUS_BYTE_DATA: + if (read_write == I2C_SMBUS_READ) { + ret = slimpro_i2c_rd(ctx, addr, command, SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + BYTE_DATA, &val); + data->byte = val; + } else { + val = data->byte; + ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + BYTE_DATA, val); + } + break; + case I2C_SMBUS_WORD_DATA: + if (read_write == I2C_SMBUS_READ) { + ret = slimpro_i2c_rd(ctx, addr, command, SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + WORD_DATA, &val); + data->word = val; + } else { + val = data->word; + ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + WORD_DATA, val); + } + break; + case I2C_SMBUS_BLOCK_DATA: + if (read_write == I2C_SMBUS_READ) { + ret = slimpro_i2c_blkrd(ctx, addr, command, + SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + I2C_SMBUS_BLOCK_MAX + 1, + IIC_SMB_WITH_DATA_LEN, + &data->block[0]); + + } else { + ret = slimpro_i2c_blkwr(ctx, addr, command, + SMBUS_CMD_LEN, + SLIMPRO_IIC_SMB_PROTOCOL, + data->block[0] + 1, + &data->block[0]); + } + break; + case I2C_SMBUS_I2C_BLOCK_DATA: + if (read_write == I2C_SMBUS_READ) { + ret = slimpro_i2c_blkrd(ctx, addr, + command, + SMBUS_CMD_LEN, + SLIMPRO_IIC_I2C_PROTOCOL, + I2C_SMBUS_BLOCK_MAX, + IIC_SMB_WITHOUT_DATA_LEN, + &data->block[1]); + } else { + ret = slimpro_i2c_blkwr(ctx, addr, command, + SMBUS_CMD_LEN, + SLIMPRO_IIC_I2C_PROTOCOL, + data->block[0], + &data->block[1]); + } + break; + default: + break; + } + return ret; +} + +/* +* Return list of supported functionality. +*/ +static u32 xgene_slimpro_i2c_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_BLOCK_DATA | + I2C_FUNC_SMBUS_I2C_BLOCK; +} + +static const struct i2c_algorithm xgene_slimpro_i2c_algorithm = { + .smbus_xfer = xgene_slimpro_i2c_xfer, + .functionality = xgene_slimpro_i2c_func, +}; + +static int xgene_slimpro_i2c_probe(struct platform_device *pdev) +{ + struct slimpro_i2c_dev *ctx; + struct i2c_adapter *adapter; + struct mbox_client *cl; + int rc; + + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + ctx->dev = &pdev->dev; + platform_set_drvdata(pdev, ctx); + cl = &ctx->mbox_client; + + /* Request mailbox channel */ + cl->dev = &pdev->dev; + init_completion(&ctx->rd_complete); + cl->tx_tout = MAILBOX_OP_TIMEOUT; + cl->knows_txdone = false; + if (acpi_disabled) { + cl->tx_block = true; + cl->rx_callback = slimpro_i2c_rx_cb; + ctx->mbox_chan = mbox_request_channel(cl, MAILBOX_I2C_INDEX); + if (IS_ERR(ctx->mbox_chan)) { + dev_err(&pdev->dev, "i2c mailbox channel request failed\n"); + return PTR_ERR(ctx->mbox_chan); + } + } else { + struct pcc_mbox_chan *pcc_chan; + const struct acpi_device_id *acpi_id; + int version = XGENE_SLIMPRO_I2C_V1; + + acpi_id = acpi_match_device(pdev->dev.driver->acpi_match_table, + &pdev->dev); + if (!acpi_id) + return -EINVAL; + + version = (int)acpi_id->driver_data; + + if (device_property_read_u32(&pdev->dev, "pcc-channel", + &ctx->mbox_idx)) + ctx->mbox_idx = MAILBOX_I2C_INDEX; + + cl->tx_block = false; + cl->rx_callback = slimpro_i2c_pcc_rx_cb; + pcc_chan = pcc_mbox_request_channel(cl, ctx->mbox_idx); + if (IS_ERR(pcc_chan)) { + dev_err(&pdev->dev, "PCC mailbox channel request failed\n"); + return PTR_ERR(pcc_chan); + } + + ctx->pcc_chan = pcc_chan; + ctx->mbox_chan = pcc_chan->mchan; + + if (!ctx->mbox_chan->mbox->txdone_irq) { + dev_err(&pdev->dev, "PCC IRQ not supported\n"); + rc = -ENOENT; + goto mbox_err; + } + + /* + * This is the shared communication region + * for the OS and Platform to communicate over. + */ + ctx->comm_base_addr = pcc_chan->shmem_base_addr; + if (ctx->comm_base_addr) { + if (version == XGENE_SLIMPRO_I2C_V2) + ctx->pcc_comm_addr = memremap( + ctx->comm_base_addr, + pcc_chan->shmem_size, + MEMREMAP_WT); + else + ctx->pcc_comm_addr = memremap( + ctx->comm_base_addr, + pcc_chan->shmem_size, + MEMREMAP_WB); + } else { + dev_err(&pdev->dev, "Failed to get PCC comm region\n"); + rc = -ENOENT; + goto mbox_err; + } + + if (!ctx->pcc_comm_addr) { + dev_err(&pdev->dev, + "Failed to ioremap PCC comm region\n"); + rc = -ENOMEM; + goto mbox_err; + } + } + rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); + if (rc) + dev_warn(&pdev->dev, "Unable to set dma mask\n"); + + /* Setup I2C adapter */ + adapter = &ctx->adapter; + snprintf(adapter->name, sizeof(adapter->name), "MAILBOX I2C"); + adapter->algo = &xgene_slimpro_i2c_algorithm; + adapter->class = I2C_CLASS_HWMON; + adapter->dev.parent = &pdev->dev; + adapter->dev.of_node = pdev->dev.of_node; + ACPI_COMPANION_SET(&adapter->dev, ACPI_COMPANION(&pdev->dev)); + i2c_set_adapdata(adapter, ctx); + rc = i2c_add_adapter(adapter); + if (rc) + goto mbox_err; + + dev_info(&pdev->dev, "Mailbox I2C Adapter registered\n"); + return 0; + +mbox_err: + if (acpi_disabled) + mbox_free_channel(ctx->mbox_chan); + else + pcc_mbox_free_channel(ctx->pcc_chan); + + return rc; +} + +static void xgene_slimpro_i2c_remove(struct platform_device *pdev) +{ + struct slimpro_i2c_dev *ctx = platform_get_drvdata(pdev); + + i2c_del_adapter(&ctx->adapter); + + if (acpi_disabled) + mbox_free_channel(ctx->mbox_chan); + else + pcc_mbox_free_channel(ctx->pcc_chan); +} + +static const struct of_device_id xgene_slimpro_i2c_dt_ids[] = { + {.compatible = "apm,xgene-slimpro-i2c" }, + {}, +}; +MODULE_DEVICE_TABLE(of, xgene_slimpro_i2c_dt_ids); + +#ifdef CONFIG_ACPI +static const struct acpi_device_id xgene_slimpro_i2c_acpi_ids[] = { + {"APMC0D40", XGENE_SLIMPRO_I2C_V1}, + {"APMC0D8B", XGENE_SLIMPRO_I2C_V2}, + {} +}; +MODULE_DEVICE_TABLE(acpi, xgene_slimpro_i2c_acpi_ids); +#endif + +static struct platform_driver xgene_slimpro_i2c_driver = { + .probe = xgene_slimpro_i2c_probe, + .remove_new = xgene_slimpro_i2c_remove, + .driver = { + .name = "xgene-slimpro-i2c", + .of_match_table = of_match_ptr(xgene_slimpro_i2c_dt_ids), + .acpi_match_table = ACPI_PTR(xgene_slimpro_i2c_acpi_ids) + }, +}; + +module_platform_driver(xgene_slimpro_i2c_driver); + +MODULE_DESCRIPTION("APM X-Gene SLIMpro I2C driver"); +MODULE_AUTHOR("Feng Kan <fkan@apm.com>"); +MODULE_AUTHOR("Hieu Le <hnle@apm.com>"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-xiic.c b/drivers/i2c/busses/i2c-xiic.c new file mode 100644 index 000000000..71391b590 --- /dev/null +++ b/drivers/i2c/busses/i2c-xiic.c @@ -0,0 +1,1400 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * i2c-xiic.c + * Copyright (c) 2002-2007 Xilinx Inc. + * Copyright (c) 2009-2010 Intel Corporation + * + * This code was implemented by Mocean Laboratories AB when porting linux + * to the automotive development board Russellville. The copyright holder + * as seen in the header is Intel corporation. + * Mocean Laboratories forked off the GNU/Linux platform work into a + * separate company called Pelagicore AB, which committed the code to the + * kernel. + */ + +/* Supports: + * Xilinx IIC + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/completion.h> +#include <linux/platform_data/i2c-xiic.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <linux/clk.h> +#include <linux/pm_runtime.h> + +#define DRIVER_NAME "xiic-i2c" +#define DYNAMIC_MODE_READ_BROKEN_BIT BIT(0) +#define SMBUS_BLOCK_READ_MIN_LEN 3 + +enum xilinx_i2c_state { + STATE_DONE, + STATE_ERROR, + STATE_START +}; + +enum xiic_endian { + LITTLE, + BIG +}; + +enum i2c_scl_freq { + REG_VALUES_100KHZ = 0, + REG_VALUES_400KHZ = 1, + REG_VALUES_1MHZ = 2 +}; + +/** + * struct xiic_i2c - Internal representation of the XIIC I2C bus + * @dev: Pointer to device structure + * @base: Memory base of the HW registers + * @completion: Completion for callers + * @adap: Kernel adapter representation + * @tx_msg: Messages from above to be sent + * @lock: Mutual exclusion + * @tx_pos: Current pos in TX message + * @nmsgs: Number of messages in tx_msg + * @rx_msg: Current RX message + * @rx_pos: Position within current RX message + * @endianness: big/little-endian byte order + * @clk: Pointer to AXI4-lite input clock + * @state: See STATE_ + * @singlemaster: Indicates bus is single master + * @dynamic: Mode of controller + * @prev_msg_tx: Previous message is Tx + * @quirks: To hold platform specific bug info + * @smbus_block_read: Flag to handle block read + * @input_clk: Input clock to I2C controller + * @i2c_clk: I2C SCL frequency + */ +struct xiic_i2c { + struct device *dev; + void __iomem *base; + struct completion completion; + struct i2c_adapter adap; + struct i2c_msg *tx_msg; + struct mutex lock; + unsigned int tx_pos; + unsigned int nmsgs; + struct i2c_msg *rx_msg; + int rx_pos; + enum xiic_endian endianness; + struct clk *clk; + enum xilinx_i2c_state state; + bool singlemaster; + bool dynamic; + bool prev_msg_tx; + u32 quirks; + bool smbus_block_read; + unsigned long input_clk; + unsigned int i2c_clk; +}; + +struct xiic_version_data { + u32 quirks; +}; + +/** + * struct timing_regs - AXI I2C timing registers that depend on I2C spec + * @tsusta: setup time for a repeated START condition + * @tsusto: setup time for a STOP condition + * @thdsta: hold time for a repeated START condition + * @tsudat: setup time for data + * @tbuf: bus free time between STOP and START + */ +struct timing_regs { + unsigned int tsusta; + unsigned int tsusto; + unsigned int thdsta; + unsigned int tsudat; + unsigned int tbuf; +}; + +/* Reg values in ns derived from I2C spec and AXI I2C PG for different frequencies */ +static const struct timing_regs timing_reg_values[] = { + { 5700, 5000, 4300, 550, 5000 }, /* Reg values for 100KHz */ + { 900, 900, 900, 400, 1600 }, /* Reg values for 400KHz */ + { 380, 380, 380, 170, 620 }, /* Reg values for 1MHz */ +}; + +#define XIIC_MSB_OFFSET 0 +#define XIIC_REG_OFFSET (0x100 + XIIC_MSB_OFFSET) + +/* + * Register offsets in bytes from RegisterBase. Three is added to the + * base offset to access LSB (IBM style) of the word + */ +#define XIIC_CR_REG_OFFSET (0x00 + XIIC_REG_OFFSET) /* Control Register */ +#define XIIC_SR_REG_OFFSET (0x04 + XIIC_REG_OFFSET) /* Status Register */ +#define XIIC_DTR_REG_OFFSET (0x08 + XIIC_REG_OFFSET) /* Data Tx Register */ +#define XIIC_DRR_REG_OFFSET (0x0C + XIIC_REG_OFFSET) /* Data Rx Register */ +#define XIIC_ADR_REG_OFFSET (0x10 + XIIC_REG_OFFSET) /* Address Register */ +#define XIIC_TFO_REG_OFFSET (0x14 + XIIC_REG_OFFSET) /* Tx FIFO Occupancy */ +#define XIIC_RFO_REG_OFFSET (0x18 + XIIC_REG_OFFSET) /* Rx FIFO Occupancy */ +#define XIIC_TBA_REG_OFFSET (0x1C + XIIC_REG_OFFSET) /* 10 Bit Address reg */ +#define XIIC_RFD_REG_OFFSET (0x20 + XIIC_REG_OFFSET) /* Rx FIFO Depth reg */ +#define XIIC_GPO_REG_OFFSET (0x24 + XIIC_REG_OFFSET) /* Output Register */ + +/* + * Timing register offsets from RegisterBase. These are used only for + * setting i2c clock frequency for the line. + */ +#define XIIC_TSUSTA_REG_OFFSET (0x28 + XIIC_REG_OFFSET) /* TSUSTA Register */ +#define XIIC_TSUSTO_REG_OFFSET (0x2C + XIIC_REG_OFFSET) /* TSUSTO Register */ +#define XIIC_THDSTA_REG_OFFSET (0x30 + XIIC_REG_OFFSET) /* THDSTA Register */ +#define XIIC_TSUDAT_REG_OFFSET (0x34 + XIIC_REG_OFFSET) /* TSUDAT Register */ +#define XIIC_TBUF_REG_OFFSET (0x38 + XIIC_REG_OFFSET) /* TBUF Register */ +#define XIIC_THIGH_REG_OFFSET (0x3C + XIIC_REG_OFFSET) /* THIGH Register */ +#define XIIC_TLOW_REG_OFFSET (0x40 + XIIC_REG_OFFSET) /* TLOW Register */ +#define XIIC_THDDAT_REG_OFFSET (0x44 + XIIC_REG_OFFSET) /* THDDAT Register */ + +/* Control Register masks */ +#define XIIC_CR_ENABLE_DEVICE_MASK 0x01 /* Device enable = 1 */ +#define XIIC_CR_TX_FIFO_RESET_MASK 0x02 /* Transmit FIFO reset=1 */ +#define XIIC_CR_MSMS_MASK 0x04 /* Master starts Txing=1 */ +#define XIIC_CR_DIR_IS_TX_MASK 0x08 /* Dir of tx. Txing=1 */ +#define XIIC_CR_NO_ACK_MASK 0x10 /* Tx Ack. NO ack = 1 */ +#define XIIC_CR_REPEATED_START_MASK 0x20 /* Repeated start = 1 */ +#define XIIC_CR_GENERAL_CALL_MASK 0x40 /* Gen Call enabled = 1 */ + +/* Status Register masks */ +#define XIIC_SR_GEN_CALL_MASK 0x01 /* 1=a mstr issued a GC */ +#define XIIC_SR_ADDR_AS_SLAVE_MASK 0x02 /* 1=when addr as slave */ +#define XIIC_SR_BUS_BUSY_MASK 0x04 /* 1 = bus is busy */ +#define XIIC_SR_MSTR_RDING_SLAVE_MASK 0x08 /* 1=Dir: mstr <-- slave */ +#define XIIC_SR_TX_FIFO_FULL_MASK 0x10 /* 1 = Tx FIFO full */ +#define XIIC_SR_RX_FIFO_FULL_MASK 0x20 /* 1 = Rx FIFO full */ +#define XIIC_SR_RX_FIFO_EMPTY_MASK 0x40 /* 1 = Rx FIFO empty */ +#define XIIC_SR_TX_FIFO_EMPTY_MASK 0x80 /* 1 = Tx FIFO empty */ + +/* Interrupt Status Register masks Interrupt occurs when... */ +#define XIIC_INTR_ARB_LOST_MASK 0x01 /* 1 = arbitration lost */ +#define XIIC_INTR_TX_ERROR_MASK 0x02 /* 1=Tx error/msg complete */ +#define XIIC_INTR_TX_EMPTY_MASK 0x04 /* 1 = Tx FIFO/reg empty */ +#define XIIC_INTR_RX_FULL_MASK 0x08 /* 1=Rx FIFO/reg=OCY level */ +#define XIIC_INTR_BNB_MASK 0x10 /* 1 = Bus not busy */ +#define XIIC_INTR_AAS_MASK 0x20 /* 1 = when addr as slave */ +#define XIIC_INTR_NAAS_MASK 0x40 /* 1 = not addr as slave */ +#define XIIC_INTR_TX_HALF_MASK 0x80 /* 1 = TX FIFO half empty */ + +/* The following constants specify the depth of the FIFOs */ +#define IIC_RX_FIFO_DEPTH 16 /* Rx fifo capacity */ +#define IIC_TX_FIFO_DEPTH 16 /* Tx fifo capacity */ + +/* The following constants specify groups of interrupts that are typically + * enabled or disables at the same time + */ +#define XIIC_TX_INTERRUPTS \ +(XIIC_INTR_TX_ERROR_MASK | XIIC_INTR_TX_EMPTY_MASK | XIIC_INTR_TX_HALF_MASK) + +#define XIIC_TX_RX_INTERRUPTS (XIIC_INTR_RX_FULL_MASK | XIIC_TX_INTERRUPTS) + +/* + * Tx Fifo upper bit masks. + */ +#define XIIC_TX_DYN_START_MASK 0x0100 /* 1 = Set dynamic start */ +#define XIIC_TX_DYN_STOP_MASK 0x0200 /* 1 = Set dynamic stop */ + +/* Dynamic mode constants */ +#define MAX_READ_LENGTH_DYNAMIC 255 /* Max length for dynamic read */ + +/* + * The following constants define the register offsets for the Interrupt + * registers. There are some holes in the memory map for reserved addresses + * to allow other registers to be added and still match the memory map of the + * interrupt controller registers + */ +#define XIIC_DGIER_OFFSET 0x1C /* Device Global Interrupt Enable Register */ +#define XIIC_IISR_OFFSET 0x20 /* Interrupt Status Register */ +#define XIIC_IIER_OFFSET 0x28 /* Interrupt Enable Register */ +#define XIIC_RESETR_OFFSET 0x40 /* Reset Register */ + +#define XIIC_RESET_MASK 0xAUL + +#define XIIC_PM_TIMEOUT 1000 /* ms */ +/* timeout waiting for the controller to respond */ +#define XIIC_I2C_TIMEOUT (msecs_to_jiffies(1000)) +/* timeout waiting for the controller finish transfers */ +#define XIIC_XFER_TIMEOUT (msecs_to_jiffies(10000)) + +/* + * The following constant is used for the device global interrupt enable + * register, to enable all interrupts for the device, this is the only bit + * in the register + */ +#define XIIC_GINTR_ENABLE_MASK 0x80000000UL + +#define xiic_tx_space(i2c) ((i2c)->tx_msg->len - (i2c)->tx_pos) +#define xiic_rx_space(i2c) ((i2c)->rx_msg->len - (i2c)->rx_pos) + +static int xiic_start_xfer(struct xiic_i2c *i2c, struct i2c_msg *msgs, int num); +static void __xiic_start_xfer(struct xiic_i2c *i2c); + +/* + * For the register read and write functions, a little-endian and big-endian + * version are necessary. Endianness is detected during the probe function. + * Only the least significant byte [doublet] of the register are ever + * accessed. This requires an offset of 3 [2] from the base address for + * big-endian systems. + */ + +static inline void xiic_setreg8(struct xiic_i2c *i2c, int reg, u8 value) +{ + if (i2c->endianness == LITTLE) + iowrite8(value, i2c->base + reg); + else + iowrite8(value, i2c->base + reg + 3); +} + +static inline u8 xiic_getreg8(struct xiic_i2c *i2c, int reg) +{ + u8 ret; + + if (i2c->endianness == LITTLE) + ret = ioread8(i2c->base + reg); + else + ret = ioread8(i2c->base + reg + 3); + return ret; +} + +static inline void xiic_setreg16(struct xiic_i2c *i2c, int reg, u16 value) +{ + if (i2c->endianness == LITTLE) + iowrite16(value, i2c->base + reg); + else + iowrite16be(value, i2c->base + reg + 2); +} + +static inline void xiic_setreg32(struct xiic_i2c *i2c, int reg, int value) +{ + if (i2c->endianness == LITTLE) + iowrite32(value, i2c->base + reg); + else + iowrite32be(value, i2c->base + reg); +} + +static inline int xiic_getreg32(struct xiic_i2c *i2c, int reg) +{ + u32 ret; + + if (i2c->endianness == LITTLE) + ret = ioread32(i2c->base + reg); + else + ret = ioread32be(i2c->base + reg); + return ret; +} + +static inline void xiic_irq_dis(struct xiic_i2c *i2c, u32 mask) +{ + u32 ier = xiic_getreg32(i2c, XIIC_IIER_OFFSET); + + xiic_setreg32(i2c, XIIC_IIER_OFFSET, ier & ~mask); +} + +static inline void xiic_irq_en(struct xiic_i2c *i2c, u32 mask) +{ + u32 ier = xiic_getreg32(i2c, XIIC_IIER_OFFSET); + + xiic_setreg32(i2c, XIIC_IIER_OFFSET, ier | mask); +} + +static inline void xiic_irq_clr(struct xiic_i2c *i2c, u32 mask) +{ + u32 isr = xiic_getreg32(i2c, XIIC_IISR_OFFSET); + + xiic_setreg32(i2c, XIIC_IISR_OFFSET, isr & mask); +} + +static inline void xiic_irq_clr_en(struct xiic_i2c *i2c, u32 mask) +{ + xiic_irq_clr(i2c, mask); + xiic_irq_en(i2c, mask); +} + +static int xiic_clear_rx_fifo(struct xiic_i2c *i2c) +{ + u8 sr; + unsigned long timeout; + + timeout = jiffies + XIIC_I2C_TIMEOUT; + for (sr = xiic_getreg8(i2c, XIIC_SR_REG_OFFSET); + !(sr & XIIC_SR_RX_FIFO_EMPTY_MASK); + sr = xiic_getreg8(i2c, XIIC_SR_REG_OFFSET)) { + xiic_getreg8(i2c, XIIC_DRR_REG_OFFSET); + if (time_after(jiffies, timeout)) { + dev_err(i2c->dev, "Failed to clear rx fifo\n"); + return -ETIMEDOUT; + } + } + + return 0; +} + +static int xiic_wait_tx_empty(struct xiic_i2c *i2c) +{ + u8 isr; + unsigned long timeout; + + timeout = jiffies + XIIC_I2C_TIMEOUT; + for (isr = xiic_getreg32(i2c, XIIC_IISR_OFFSET); + !(isr & XIIC_INTR_TX_EMPTY_MASK); + isr = xiic_getreg32(i2c, XIIC_IISR_OFFSET)) { + if (time_after(jiffies, timeout)) { + dev_err(i2c->dev, "Timeout waiting at Tx empty\n"); + return -ETIMEDOUT; + } + } + + return 0; +} + +/** + * xiic_setclk - Sets the configured clock rate + * @i2c: Pointer to the xiic device structure + * + * The timing register values are calculated according to the input clock + * frequency and configured scl frequency. For details, please refer the + * AXI I2C PG and NXP I2C Spec. + * Supported frequencies are 100KHz, 400KHz and 1MHz. + * + * Return: 0 on success (Supported frequency selected or not configurable in SW) + * -EINVAL on failure (scl frequency not supported or THIGH is 0) + */ +static int xiic_setclk(struct xiic_i2c *i2c) +{ + unsigned int clk_in_mhz; + unsigned int index = 0; + u32 reg_val; + + dev_dbg(i2c->adap.dev.parent, + "%s entry, i2c->input_clk: %ld, i2c->i2c_clk: %d\n", + __func__, i2c->input_clk, i2c->i2c_clk); + + /* If not specified in DT, do not configure in SW. Rely only on Vivado design */ + if (!i2c->i2c_clk || !i2c->input_clk) + return 0; + + clk_in_mhz = DIV_ROUND_UP(i2c->input_clk, 1000000); + + switch (i2c->i2c_clk) { + case I2C_MAX_FAST_MODE_PLUS_FREQ: + index = REG_VALUES_1MHZ; + break; + case I2C_MAX_FAST_MODE_FREQ: + index = REG_VALUES_400KHZ; + break; + case I2C_MAX_STANDARD_MODE_FREQ: + index = REG_VALUES_100KHZ; + break; + default: + dev_warn(i2c->adap.dev.parent, "Unsupported scl frequency\n"); + return -EINVAL; + } + + /* + * Value to be stored in a register is the number of clock cycles required + * for the time duration. So the time is divided by the input clock time + * period to get the number of clock cycles required. Refer Xilinx AXI I2C + * PG document and I2C specification for further details. + */ + + /* THIGH - Depends on SCL clock frequency(i2c_clk) as below */ + reg_val = (DIV_ROUND_UP(i2c->input_clk, 2 * i2c->i2c_clk)) - 7; + if (reg_val == 0) + return -EINVAL; + + xiic_setreg32(i2c, XIIC_THIGH_REG_OFFSET, reg_val - 1); + + /* TLOW - Value same as THIGH */ + xiic_setreg32(i2c, XIIC_TLOW_REG_OFFSET, reg_val - 1); + + /* TSUSTA */ + reg_val = (timing_reg_values[index].tsusta * clk_in_mhz) / 1000; + xiic_setreg32(i2c, XIIC_TSUSTA_REG_OFFSET, reg_val - 1); + + /* TSUSTO */ + reg_val = (timing_reg_values[index].tsusto * clk_in_mhz) / 1000; + xiic_setreg32(i2c, XIIC_TSUSTO_REG_OFFSET, reg_val - 1); + + /* THDSTA */ + reg_val = (timing_reg_values[index].thdsta * clk_in_mhz) / 1000; + xiic_setreg32(i2c, XIIC_THDSTA_REG_OFFSET, reg_val - 1); + + /* TSUDAT */ + reg_val = (timing_reg_values[index].tsudat * clk_in_mhz) / 1000; + xiic_setreg32(i2c, XIIC_TSUDAT_REG_OFFSET, reg_val - 1); + + /* TBUF */ + reg_val = (timing_reg_values[index].tbuf * clk_in_mhz) / 1000; + xiic_setreg32(i2c, XIIC_TBUF_REG_OFFSET, reg_val - 1); + + /* THDDAT */ + xiic_setreg32(i2c, XIIC_THDDAT_REG_OFFSET, 1); + + return 0; +} + +static int xiic_reinit(struct xiic_i2c *i2c) +{ + int ret; + + xiic_setreg32(i2c, XIIC_RESETR_OFFSET, XIIC_RESET_MASK); + + ret = xiic_setclk(i2c); + if (ret) + return ret; + + /* Set receive Fifo depth to maximum (zero based). */ + xiic_setreg8(i2c, XIIC_RFD_REG_OFFSET, IIC_RX_FIFO_DEPTH - 1); + + /* Reset Tx Fifo. */ + xiic_setreg8(i2c, XIIC_CR_REG_OFFSET, XIIC_CR_TX_FIFO_RESET_MASK); + + /* Enable IIC Device, remove Tx Fifo reset & disable general call. */ + xiic_setreg8(i2c, XIIC_CR_REG_OFFSET, XIIC_CR_ENABLE_DEVICE_MASK); + + /* make sure RX fifo is empty */ + ret = xiic_clear_rx_fifo(i2c); + if (ret) + return ret; + + /* Enable interrupts */ + xiic_setreg32(i2c, XIIC_DGIER_OFFSET, XIIC_GINTR_ENABLE_MASK); + + xiic_irq_clr_en(i2c, XIIC_INTR_ARB_LOST_MASK); + + return 0; +} + +static void xiic_deinit(struct xiic_i2c *i2c) +{ + u8 cr; + + xiic_setreg32(i2c, XIIC_RESETR_OFFSET, XIIC_RESET_MASK); + + /* Disable IIC Device. */ + cr = xiic_getreg8(i2c, XIIC_CR_REG_OFFSET); + xiic_setreg8(i2c, XIIC_CR_REG_OFFSET, cr & ~XIIC_CR_ENABLE_DEVICE_MASK); +} + +static void xiic_smbus_block_read_setup(struct xiic_i2c *i2c) +{ + u8 rxmsg_len, rfd_set = 0; + + /* + * Clear the I2C_M_RECV_LEN flag to avoid setting + * message length again + */ + i2c->rx_msg->flags &= ~I2C_M_RECV_LEN; + + /* Set smbus_block_read flag to identify in isr */ + i2c->smbus_block_read = true; + + /* Read byte from rx fifo and set message length */ + rxmsg_len = xiic_getreg8(i2c, XIIC_DRR_REG_OFFSET); + + i2c->rx_msg->buf[i2c->rx_pos++] = rxmsg_len; + + /* Check if received length is valid */ + if (rxmsg_len <= I2C_SMBUS_BLOCK_MAX) { + /* Set Receive fifo depth */ + if (rxmsg_len > IIC_RX_FIFO_DEPTH) { + /* + * When Rx msg len greater than or equal to Rx fifo capacity + * Receive fifo depth should set to Rx fifo capacity minus 1 + */ + rfd_set = IIC_RX_FIFO_DEPTH - 1; + i2c->rx_msg->len = rxmsg_len + 1; + } else if ((rxmsg_len == 1) || + (rxmsg_len == 0)) { + /* + * Minimum of 3 bytes required to exit cleanly. 1 byte + * already received, Second byte is being received. Have + * to set NACK in read_rx before receiving the last byte + */ + rfd_set = 0; + i2c->rx_msg->len = SMBUS_BLOCK_READ_MIN_LEN; + } else { + /* + * When Rx msg len less than Rx fifo capacity + * Receive fifo depth should set to Rx msg len minus 2 + */ + rfd_set = rxmsg_len - 2; + i2c->rx_msg->len = rxmsg_len + 1; + } + xiic_setreg8(i2c, XIIC_RFD_REG_OFFSET, rfd_set); + + return; + } + + /* Invalid message length, trigger STATE_ERROR with tx_msg_len in ISR */ + i2c->tx_msg->len = 3; + i2c->smbus_block_read = false; + dev_err(i2c->adap.dev.parent, "smbus_block_read Invalid msg length\n"); +} + +static void xiic_read_rx(struct xiic_i2c *i2c) +{ + u8 bytes_in_fifo, cr = 0, bytes_to_read = 0; + u32 bytes_rem = 0; + int i; + + bytes_in_fifo = xiic_getreg8(i2c, XIIC_RFO_REG_OFFSET) + 1; + + dev_dbg(i2c->adap.dev.parent, + "%s entry, bytes in fifo: %d, rem: %d, SR: 0x%x, CR: 0x%x\n", + __func__, bytes_in_fifo, xiic_rx_space(i2c), + xiic_getreg8(i2c, XIIC_SR_REG_OFFSET), + xiic_getreg8(i2c, XIIC_CR_REG_OFFSET)); + + if (bytes_in_fifo > xiic_rx_space(i2c)) + bytes_in_fifo = xiic_rx_space(i2c); + + bytes_to_read = bytes_in_fifo; + + if (!i2c->dynamic) { + bytes_rem = xiic_rx_space(i2c) - bytes_in_fifo; + + /* Set msg length if smbus_block_read */ + if (i2c->rx_msg->flags & I2C_M_RECV_LEN) { + xiic_smbus_block_read_setup(i2c); + return; + } + + if (bytes_rem > IIC_RX_FIFO_DEPTH) { + bytes_to_read = bytes_in_fifo; + } else if (bytes_rem > 1) { + bytes_to_read = bytes_rem - 1; + } else if (bytes_rem == 1) { + bytes_to_read = 1; + /* Set NACK in CR to indicate slave transmitter */ + cr = xiic_getreg8(i2c, XIIC_CR_REG_OFFSET); + xiic_setreg8(i2c, XIIC_CR_REG_OFFSET, cr | + XIIC_CR_NO_ACK_MASK); + } else if (bytes_rem == 0) { + bytes_to_read = bytes_in_fifo; + + /* Generate stop on the bus if it is last message */ + if (i2c->nmsgs == 1) { + cr = xiic_getreg8(i2c, XIIC_CR_REG_OFFSET); + xiic_setreg8(i2c, XIIC_CR_REG_OFFSET, cr & + ~XIIC_CR_MSMS_MASK); + } + + /* Make TXACK=0, clean up for next transaction */ + cr = xiic_getreg8(i2c, XIIC_CR_REG_OFFSET); + xiic_setreg8(i2c, XIIC_CR_REG_OFFSET, cr & + ~XIIC_CR_NO_ACK_MASK); + } + } + + /* Read the fifo */ + for (i = 0; i < bytes_to_read; i++) { + i2c->rx_msg->buf[i2c->rx_pos++] = + xiic_getreg8(i2c, XIIC_DRR_REG_OFFSET); + } + + if (i2c->dynamic) { + u8 bytes; + + /* Receive remaining bytes if less than fifo depth */ + bytes = min_t(u8, xiic_rx_space(i2c), IIC_RX_FIFO_DEPTH); + bytes--; + xiic_setreg8(i2c, XIIC_RFD_REG_OFFSET, bytes); + } +} + +static int xiic_tx_fifo_space(struct xiic_i2c *i2c) +{ + /* return the actual space left in the FIFO */ + return IIC_TX_FIFO_DEPTH - xiic_getreg8(i2c, XIIC_TFO_REG_OFFSET) - 1; +} + +static void xiic_fill_tx_fifo(struct xiic_i2c *i2c) +{ + u8 fifo_space = xiic_tx_fifo_space(i2c); + int len = xiic_tx_space(i2c); + + len = (len > fifo_space) ? fifo_space : len; + + dev_dbg(i2c->adap.dev.parent, "%s entry, len: %d, fifo space: %d\n", + __func__, len, fifo_space); + + while (len--) { + u16 data = i2c->tx_msg->buf[i2c->tx_pos++]; + + if (!xiic_tx_space(i2c) && i2c->nmsgs == 1) { + /* last message in transfer -> STOP */ + if (i2c->dynamic) { + data |= XIIC_TX_DYN_STOP_MASK; + } else { + u8 cr; + int status; + + /* Wait till FIFO is empty so STOP is sent last */ + status = xiic_wait_tx_empty(i2c); + if (status) + return; + + /* Write to CR to stop */ + cr = xiic_getreg8(i2c, XIIC_CR_REG_OFFSET); + xiic_setreg8(i2c, XIIC_CR_REG_OFFSET, cr & + ~XIIC_CR_MSMS_MASK); + } + dev_dbg(i2c->adap.dev.parent, "%s TX STOP\n", __func__); + } + xiic_setreg16(i2c, XIIC_DTR_REG_OFFSET, data); + } +} + +static void xiic_wakeup(struct xiic_i2c *i2c, enum xilinx_i2c_state code) +{ + i2c->tx_msg = NULL; + i2c->rx_msg = NULL; + i2c->nmsgs = 0; + i2c->state = code; + complete(&i2c->completion); +} + +static irqreturn_t xiic_process(int irq, void *dev_id) +{ + struct xiic_i2c *i2c = dev_id; + u32 pend, isr, ier; + u32 clr = 0; + int xfer_more = 0; + int wakeup_req = 0; + enum xilinx_i2c_state wakeup_code = STATE_DONE; + int ret; + + /* Get the interrupt Status from the IPIF. There is no clearing of + * interrupts in the IPIF. Interrupts must be cleared at the source. + * To find which interrupts are pending; AND interrupts pending with + * interrupts masked. + */ + mutex_lock(&i2c->lock); + isr = xiic_getreg32(i2c, XIIC_IISR_OFFSET); + ier = xiic_getreg32(i2c, XIIC_IIER_OFFSET); + pend = isr & ier; + + dev_dbg(i2c->adap.dev.parent, "%s: IER: 0x%x, ISR: 0x%x, pend: 0x%x\n", + __func__, ier, isr, pend); + dev_dbg(i2c->adap.dev.parent, "%s: SR: 0x%x, msg: %p, nmsgs: %d\n", + __func__, xiic_getreg8(i2c, XIIC_SR_REG_OFFSET), + i2c->tx_msg, i2c->nmsgs); + dev_dbg(i2c->adap.dev.parent, "%s, ISR: 0x%x, CR: 0x%x\n", + __func__, xiic_getreg32(i2c, XIIC_IISR_OFFSET), + xiic_getreg8(i2c, XIIC_CR_REG_OFFSET)); + + /* Service requesting interrupt */ + if ((pend & XIIC_INTR_ARB_LOST_MASK) || + ((pend & XIIC_INTR_TX_ERROR_MASK) && + !(pend & XIIC_INTR_RX_FULL_MASK))) { + /* bus arbritration lost, or... + * Transmit error _OR_ RX completed + * if this happens when RX_FULL is not set + * this is probably a TX error + */ + + dev_dbg(i2c->adap.dev.parent, "%s error\n", __func__); + + /* dynamic mode seem to suffer from problems if we just flushes + * fifos and the next message is a TX with len 0 (only addr) + * reset the IP instead of just flush fifos + */ + ret = xiic_reinit(i2c); + if (ret < 0) + dev_dbg(i2c->adap.dev.parent, "reinit failed\n"); + + if (i2c->rx_msg) { + wakeup_req = 1; + wakeup_code = STATE_ERROR; + } + if (i2c->tx_msg) { + wakeup_req = 1; + wakeup_code = STATE_ERROR; + } + /* don't try to handle other events */ + goto out; + } + if (pend & XIIC_INTR_RX_FULL_MASK) { + /* Receive register/FIFO is full */ + + clr |= XIIC_INTR_RX_FULL_MASK; + if (!i2c->rx_msg) { + dev_dbg(i2c->adap.dev.parent, + "%s unexpected RX IRQ\n", __func__); + xiic_clear_rx_fifo(i2c); + goto out; + } + + xiic_read_rx(i2c); + if (xiic_rx_space(i2c) == 0) { + /* this is the last part of the message */ + i2c->rx_msg = NULL; + + /* also clear TX error if there (RX complete) */ + clr |= (isr & XIIC_INTR_TX_ERROR_MASK); + + dev_dbg(i2c->adap.dev.parent, + "%s end of message, nmsgs: %d\n", + __func__, i2c->nmsgs); + + /* send next message if this wasn't the last, + * otherwise the transfer will be finialise when + * receiving the bus not busy interrupt + */ + if (i2c->nmsgs > 1) { + i2c->nmsgs--; + i2c->tx_msg++; + dev_dbg(i2c->adap.dev.parent, + "%s will start next...\n", __func__); + xfer_more = 1; + } + } + } + if (pend & (XIIC_INTR_TX_EMPTY_MASK | XIIC_INTR_TX_HALF_MASK)) { + /* Transmit register/FIFO is empty or ½ empty */ + + clr |= (pend & + (XIIC_INTR_TX_EMPTY_MASK | XIIC_INTR_TX_HALF_MASK)); + + if (!i2c->tx_msg) { + dev_dbg(i2c->adap.dev.parent, + "%s unexpected TX IRQ\n", __func__); + goto out; + } + + xiic_fill_tx_fifo(i2c); + + /* current message sent and there is space in the fifo */ + if (!xiic_tx_space(i2c) && xiic_tx_fifo_space(i2c) >= 2) { + dev_dbg(i2c->adap.dev.parent, + "%s end of message sent, nmsgs: %d\n", + __func__, i2c->nmsgs); + if (i2c->nmsgs > 1) { + i2c->nmsgs--; + i2c->tx_msg++; + xfer_more = 1; + } else { + xiic_irq_dis(i2c, XIIC_INTR_TX_HALF_MASK); + + dev_dbg(i2c->adap.dev.parent, + "%s Got TX IRQ but no more to do...\n", + __func__); + } + } else if (!xiic_tx_space(i2c) && (i2c->nmsgs == 1)) + /* current frame is sent and is last, + * make sure to disable tx half + */ + xiic_irq_dis(i2c, XIIC_INTR_TX_HALF_MASK); + } + + if (pend & XIIC_INTR_BNB_MASK) { + /* IIC bus has transitioned to not busy */ + clr |= XIIC_INTR_BNB_MASK; + + /* The bus is not busy, disable BusNotBusy interrupt */ + xiic_irq_dis(i2c, XIIC_INTR_BNB_MASK); + + if (i2c->tx_msg && i2c->smbus_block_read) { + i2c->smbus_block_read = false; + /* Set requested message len=1 to indicate STATE_DONE */ + i2c->tx_msg->len = 1; + } + + if (!i2c->tx_msg) + goto out; + + wakeup_req = 1; + + if (i2c->nmsgs == 1 && !i2c->rx_msg && + xiic_tx_space(i2c) == 0) + wakeup_code = STATE_DONE; + else + wakeup_code = STATE_ERROR; + } + +out: + dev_dbg(i2c->adap.dev.parent, "%s clr: 0x%x\n", __func__, clr); + + xiic_setreg32(i2c, XIIC_IISR_OFFSET, clr); + if (xfer_more) + __xiic_start_xfer(i2c); + if (wakeup_req) + xiic_wakeup(i2c, wakeup_code); + + WARN_ON(xfer_more && wakeup_req); + + mutex_unlock(&i2c->lock); + return IRQ_HANDLED; +} + +static int xiic_bus_busy(struct xiic_i2c *i2c) +{ + u8 sr = xiic_getreg8(i2c, XIIC_SR_REG_OFFSET); + + return (sr & XIIC_SR_BUS_BUSY_MASK) ? -EBUSY : 0; +} + +static int xiic_busy(struct xiic_i2c *i2c) +{ + int tries = 3; + int err; + + if (i2c->tx_msg || i2c->rx_msg) + return -EBUSY; + + /* In single master mode bus can only be busy, when in use by this + * driver. If the register indicates bus being busy for some reason we + * should ignore it, since bus will never be released and i2c will be + * stuck forever. + */ + if (i2c->singlemaster) { + return 0; + } + + /* for instance if previous transfer was terminated due to TX error + * it might be that the bus is on it's way to become available + * give it at most 3 ms to wake + */ + err = xiic_bus_busy(i2c); + while (err && tries--) { + msleep(1); + err = xiic_bus_busy(i2c); + } + + return err; +} + +static void xiic_start_recv(struct xiic_i2c *i2c) +{ + u16 rx_watermark; + u8 cr = 0, rfd_set = 0; + struct i2c_msg *msg = i2c->rx_msg = i2c->tx_msg; + + dev_dbg(i2c->adap.dev.parent, "%s entry, ISR: 0x%x, CR: 0x%x\n", + __func__, xiic_getreg32(i2c, XIIC_IISR_OFFSET), + xiic_getreg8(i2c, XIIC_CR_REG_OFFSET)); + + /* Disable Tx interrupts */ + xiic_irq_dis(i2c, XIIC_INTR_TX_HALF_MASK | XIIC_INTR_TX_EMPTY_MASK); + + if (i2c->dynamic) { + u8 bytes; + u16 val; + + /* Clear and enable Rx full interrupt. */ + xiic_irq_clr_en(i2c, XIIC_INTR_RX_FULL_MASK | + XIIC_INTR_TX_ERROR_MASK); + + /* + * We want to get all but last byte, because the TX_ERROR IRQ + * is used to indicate error ACK on the address, and + * negative ack on the last received byte, so to not mix + * them receive all but last. + * In the case where there is only one byte to receive + * we can check if ERROR and RX full is set at the same time + */ + rx_watermark = msg->len; + bytes = min_t(u8, rx_watermark, IIC_RX_FIFO_DEPTH); + + if (rx_watermark > 0) + bytes--; + xiic_setreg8(i2c, XIIC_RFD_REG_OFFSET, bytes); + + /* write the address */ + xiic_setreg16(i2c, XIIC_DTR_REG_OFFSET, + i2c_8bit_addr_from_msg(msg) | + XIIC_TX_DYN_START_MASK); + + /* If last message, include dynamic stop bit with length */ + val = (i2c->nmsgs == 1) ? XIIC_TX_DYN_STOP_MASK : 0; + val |= msg->len; + + xiic_setreg16(i2c, XIIC_DTR_REG_OFFSET, val); + + xiic_irq_clr_en(i2c, XIIC_INTR_BNB_MASK); + } else { + /* + * If previous message is Tx, make sure that Tx FIFO is empty + * before starting a new transfer as the repeated start in + * standard mode can corrupt the transaction if there are + * still bytes to be transmitted in FIFO + */ + if (i2c->prev_msg_tx) { + int status; + + status = xiic_wait_tx_empty(i2c); + if (status) + return; + } + + cr = xiic_getreg8(i2c, XIIC_CR_REG_OFFSET); + + /* Set Receive fifo depth */ + rx_watermark = msg->len; + if (rx_watermark > IIC_RX_FIFO_DEPTH) { + rfd_set = IIC_RX_FIFO_DEPTH - 1; + } else if (rx_watermark == 1) { + rfd_set = rx_watermark - 1; + + /* Set No_ACK, except for smbus_block_read */ + if (!(i2c->rx_msg->flags & I2C_M_RECV_LEN)) { + /* Handle single byte transfer separately */ + cr |= XIIC_CR_NO_ACK_MASK; + } + } else if (rx_watermark == 0) { + rfd_set = rx_watermark; + } else { + rfd_set = rx_watermark - 2; + } + /* Check if RSTA should be set */ + if (cr & XIIC_CR_MSMS_MASK) { + /* Already a master, RSTA should be set */ + xiic_setreg8(i2c, XIIC_CR_REG_OFFSET, (cr | + XIIC_CR_REPEATED_START_MASK) & + ~(XIIC_CR_DIR_IS_TX_MASK)); + } + + xiic_setreg8(i2c, XIIC_RFD_REG_OFFSET, rfd_set); + + /* Clear and enable Rx full and transmit complete interrupts */ + xiic_irq_clr_en(i2c, XIIC_INTR_RX_FULL_MASK | + XIIC_INTR_TX_ERROR_MASK); + + /* Write the address */ + xiic_setreg16(i2c, XIIC_DTR_REG_OFFSET, + i2c_8bit_addr_from_msg(msg)); + + /* Write to Control Register,to start transaction in Rx mode */ + if ((cr & XIIC_CR_MSMS_MASK) == 0) { + xiic_setreg8(i2c, XIIC_CR_REG_OFFSET, (cr | + XIIC_CR_MSMS_MASK) + & ~(XIIC_CR_DIR_IS_TX_MASK)); + } + dev_dbg(i2c->adap.dev.parent, "%s end, ISR: 0x%x, CR: 0x%x\n", + __func__, xiic_getreg32(i2c, XIIC_IISR_OFFSET), + xiic_getreg8(i2c, XIIC_CR_REG_OFFSET)); + } + + if (i2c->nmsgs == 1) + /* very last, enable bus not busy as well */ + xiic_irq_clr_en(i2c, XIIC_INTR_BNB_MASK); + + /* the message is tx:ed */ + i2c->tx_pos = msg->len; + + /* Enable interrupts */ + xiic_setreg32(i2c, XIIC_DGIER_OFFSET, XIIC_GINTR_ENABLE_MASK); + + i2c->prev_msg_tx = false; +} + +static void xiic_start_send(struct xiic_i2c *i2c) +{ + u8 cr = 0; + u16 data; + struct i2c_msg *msg = i2c->tx_msg; + + dev_dbg(i2c->adap.dev.parent, "%s entry, msg: %p, len: %d", + __func__, msg, msg->len); + dev_dbg(i2c->adap.dev.parent, "%s entry, ISR: 0x%x, CR: 0x%x\n", + __func__, xiic_getreg32(i2c, XIIC_IISR_OFFSET), + xiic_getreg8(i2c, XIIC_CR_REG_OFFSET)); + + if (i2c->dynamic) { + /* write the address */ + data = i2c_8bit_addr_from_msg(msg) | + XIIC_TX_DYN_START_MASK; + + if (i2c->nmsgs == 1 && msg->len == 0) + /* no data and last message -> add STOP */ + data |= XIIC_TX_DYN_STOP_MASK; + + xiic_setreg16(i2c, XIIC_DTR_REG_OFFSET, data); + + /* Clear any pending Tx empty, Tx Error and then enable them */ + xiic_irq_clr_en(i2c, XIIC_INTR_TX_EMPTY_MASK | + XIIC_INTR_TX_ERROR_MASK | + XIIC_INTR_BNB_MASK | + ((i2c->nmsgs > 1 || xiic_tx_space(i2c)) ? + XIIC_INTR_TX_HALF_MASK : 0)); + + xiic_fill_tx_fifo(i2c); + } else { + /* + * If previous message is Tx, make sure that Tx FIFO is empty + * before starting a new transfer as the repeated start in + * standard mode can corrupt the transaction if there are + * still bytes to be transmitted in FIFO + */ + if (i2c->prev_msg_tx) { + int status; + + status = xiic_wait_tx_empty(i2c); + if (status) + return; + } + /* Check if RSTA should be set */ + cr = xiic_getreg8(i2c, XIIC_CR_REG_OFFSET); + if (cr & XIIC_CR_MSMS_MASK) { + /* Already a master, RSTA should be set */ + xiic_setreg8(i2c, XIIC_CR_REG_OFFSET, (cr | + XIIC_CR_REPEATED_START_MASK | + XIIC_CR_DIR_IS_TX_MASK) & + ~(XIIC_CR_NO_ACK_MASK)); + } + + /* Write address to FIFO */ + data = i2c_8bit_addr_from_msg(msg); + xiic_setreg16(i2c, XIIC_DTR_REG_OFFSET, data); + + /* Fill fifo */ + xiic_fill_tx_fifo(i2c); + + if ((cr & XIIC_CR_MSMS_MASK) == 0) { + /* Start Tx by writing to CR */ + cr = xiic_getreg8(i2c, XIIC_CR_REG_OFFSET); + xiic_setreg8(i2c, XIIC_CR_REG_OFFSET, cr | + XIIC_CR_MSMS_MASK | + XIIC_CR_DIR_IS_TX_MASK); + } + + /* Clear any pending Tx empty, Tx Error and then enable them */ + xiic_irq_clr_en(i2c, XIIC_INTR_TX_EMPTY_MASK | + XIIC_INTR_TX_ERROR_MASK | + XIIC_INTR_BNB_MASK); + } + i2c->prev_msg_tx = true; +} + +static void __xiic_start_xfer(struct xiic_i2c *i2c) +{ + int fifo_space = xiic_tx_fifo_space(i2c); + + dev_dbg(i2c->adap.dev.parent, "%s entry, msg: %p, fifos space: %d\n", + __func__, i2c->tx_msg, fifo_space); + + if (!i2c->tx_msg) + return; + + i2c->rx_pos = 0; + i2c->tx_pos = 0; + i2c->state = STATE_START; + if (i2c->tx_msg->flags & I2C_M_RD) { + /* we dont date putting several reads in the FIFO */ + xiic_start_recv(i2c); + } else { + xiic_start_send(i2c); + } +} + +static int xiic_start_xfer(struct xiic_i2c *i2c, struct i2c_msg *msgs, int num) +{ + bool broken_read, max_read_len, smbus_blk_read; + int ret, count; + + mutex_lock(&i2c->lock); + + ret = xiic_busy(i2c); + if (ret) + goto out; + + i2c->tx_msg = msgs; + i2c->rx_msg = NULL; + i2c->nmsgs = num; + init_completion(&i2c->completion); + + /* Decide standard mode or Dynamic mode */ + i2c->dynamic = true; + + /* Initialize prev message type */ + i2c->prev_msg_tx = false; + + /* + * Scan through nmsgs, use dynamic mode when none of the below three + * conditions occur. We need standard mode even if one condition holds + * true in the entire array of messages in a single transfer. + * If read transaction as dynamic mode is broken for delayed reads + * in xlnx,axi-iic-2.0 / xlnx,xps-iic-2.00.a IP versions. + * If read length is > 255 bytes. + * If smbus_block_read transaction. + */ + for (count = 0; count < i2c->nmsgs; count++) { + broken_read = (i2c->quirks & DYNAMIC_MODE_READ_BROKEN_BIT) && + (i2c->tx_msg[count].flags & I2C_M_RD); + max_read_len = (i2c->tx_msg[count].flags & I2C_M_RD) && + (i2c->tx_msg[count].len > MAX_READ_LENGTH_DYNAMIC); + smbus_blk_read = (i2c->tx_msg[count].flags & I2C_M_RECV_LEN); + + if (broken_read || max_read_len || smbus_blk_read) { + i2c->dynamic = false; + break; + } + } + + ret = xiic_reinit(i2c); + if (!ret) + __xiic_start_xfer(i2c); + +out: + mutex_unlock(&i2c->lock); + + return ret; +} + +static int xiic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + struct xiic_i2c *i2c = i2c_get_adapdata(adap); + int err; + + dev_dbg(adap->dev.parent, "%s entry SR: 0x%x\n", __func__, + xiic_getreg8(i2c, XIIC_SR_REG_OFFSET)); + + err = pm_runtime_resume_and_get(i2c->dev); + if (err < 0) + return err; + + err = xiic_start_xfer(i2c, msgs, num); + if (err < 0) { + dev_err(adap->dev.parent, "Error xiic_start_xfer\n"); + goto out; + } + + err = wait_for_completion_timeout(&i2c->completion, XIIC_XFER_TIMEOUT); + mutex_lock(&i2c->lock); + if (err == 0) { /* Timeout */ + i2c->tx_msg = NULL; + i2c->rx_msg = NULL; + i2c->nmsgs = 0; + err = -ETIMEDOUT; + } else { + err = (i2c->state == STATE_DONE) ? num : -EIO; + } + mutex_unlock(&i2c->lock); + +out: + pm_runtime_mark_last_busy(i2c->dev); + pm_runtime_put_autosuspend(i2c->dev); + return err; +} + +static u32 xiic_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_BLOCK_DATA; +} + +static const struct i2c_algorithm xiic_algorithm = { + .master_xfer = xiic_xfer, + .functionality = xiic_func, +}; + +static const struct i2c_adapter xiic_adapter = { + .owner = THIS_MODULE, + .class = I2C_CLASS_DEPRECATED, + .algo = &xiic_algorithm, +}; + +#if defined(CONFIG_OF) +static const struct xiic_version_data xiic_2_00 = { + .quirks = DYNAMIC_MODE_READ_BROKEN_BIT, +}; + +static const struct of_device_id xiic_of_match[] = { + { .compatible = "xlnx,xps-iic-2.00.a", .data = &xiic_2_00 }, + { .compatible = "xlnx,axi-iic-2.1", }, + {}, +}; +MODULE_DEVICE_TABLE(of, xiic_of_match); +#endif + +static int xiic_i2c_probe(struct platform_device *pdev) +{ + struct xiic_i2c *i2c; + struct xiic_i2c_platform_data *pdata; + const struct of_device_id *match; + struct resource *res; + int ret, irq; + u8 i; + u32 sr; + + i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + match = of_match_node(xiic_of_match, pdev->dev.of_node); + if (match && match->data) { + const struct xiic_version_data *data = match->data; + + i2c->quirks = data->quirks; + } + + i2c->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(i2c->base)) + return PTR_ERR(i2c->base); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + pdata = dev_get_platdata(&pdev->dev); + + /* hook up driver to tree */ + platform_set_drvdata(pdev, i2c); + i2c->adap = xiic_adapter; + i2c_set_adapdata(&i2c->adap, i2c); + i2c->adap.dev.parent = &pdev->dev; + i2c->adap.dev.of_node = pdev->dev.of_node; + snprintf(i2c->adap.name, sizeof(i2c->adap.name), + DRIVER_NAME " %s", pdev->name); + + mutex_init(&i2c->lock); + + i2c->clk = devm_clk_get_enabled(&pdev->dev, NULL); + if (IS_ERR(i2c->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(i2c->clk), + "failed to enable input clock.\n"); + + i2c->dev = &pdev->dev; + pm_runtime_set_autosuspend_delay(i2c->dev, XIIC_PM_TIMEOUT); + pm_runtime_use_autosuspend(i2c->dev); + pm_runtime_set_active(i2c->dev); + pm_runtime_enable(i2c->dev); + + /* SCL frequency configuration */ + i2c->input_clk = clk_get_rate(i2c->clk); + ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency", + &i2c->i2c_clk); + /* If clock-frequency not specified in DT, do not configure in SW */ + if (ret || i2c->i2c_clk > I2C_MAX_FAST_MODE_PLUS_FREQ) + i2c->i2c_clk = 0; + + ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, + xiic_process, IRQF_ONESHOT, + pdev->name, i2c); + + if (ret < 0) { + dev_err(&pdev->dev, "Cannot claim IRQ\n"); + goto err_pm_disable; + } + + i2c->singlemaster = + of_property_read_bool(pdev->dev.of_node, "single-master"); + + /* + * Detect endianness + * Try to reset the TX FIFO. Then check the EMPTY flag. If it is not + * set, assume that the endianness was wrong and swap. + */ + i2c->endianness = LITTLE; + xiic_setreg32(i2c, XIIC_CR_REG_OFFSET, XIIC_CR_TX_FIFO_RESET_MASK); + /* Reset is cleared in xiic_reinit */ + sr = xiic_getreg32(i2c, XIIC_SR_REG_OFFSET); + if (!(sr & XIIC_SR_TX_FIFO_EMPTY_MASK)) + i2c->endianness = BIG; + + ret = xiic_reinit(i2c); + if (ret < 0) { + dev_err(&pdev->dev, "Cannot xiic_reinit\n"); + goto err_pm_disable; + } + + /* add i2c adapter to i2c tree */ + ret = i2c_add_adapter(&i2c->adap); + if (ret) { + xiic_deinit(i2c); + goto err_pm_disable; + } + + if (pdata) { + /* add in known devices to the bus */ + for (i = 0; i < pdata->num_devices; i++) + i2c_new_client_device(&i2c->adap, pdata->devices + i); + } + + dev_dbg(&pdev->dev, "mmio %08lx irq %d scl clock frequency %d\n", + (unsigned long)res->start, irq, i2c->i2c_clk); + + return 0; + +err_pm_disable: + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_disable(&pdev->dev); + + return ret; +} + +static void xiic_i2c_remove(struct platform_device *pdev) +{ + struct xiic_i2c *i2c = platform_get_drvdata(pdev); + int ret; + + /* remove adapter & data */ + i2c_del_adapter(&i2c->adap); + + ret = pm_runtime_get_sync(i2c->dev); + + if (ret < 0) + dev_warn(&pdev->dev, "Failed to activate device for removal (%pe)\n", + ERR_PTR(ret)); + else + xiic_deinit(i2c); + + pm_runtime_put_sync(i2c->dev); + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_dont_use_autosuspend(&pdev->dev); +} + +static int __maybe_unused xiic_i2c_runtime_suspend(struct device *dev) +{ + struct xiic_i2c *i2c = dev_get_drvdata(dev); + + clk_disable(i2c->clk); + + return 0; +} + +static int __maybe_unused xiic_i2c_runtime_resume(struct device *dev) +{ + struct xiic_i2c *i2c = dev_get_drvdata(dev); + int ret; + + ret = clk_enable(i2c->clk); + if (ret) { + dev_err(dev, "Cannot enable clock.\n"); + return ret; + } + + return 0; +} + +static const struct dev_pm_ops xiic_dev_pm_ops = { + SET_RUNTIME_PM_OPS(xiic_i2c_runtime_suspend, + xiic_i2c_runtime_resume, NULL) +}; + +static struct platform_driver xiic_i2c_driver = { + .probe = xiic_i2c_probe, + .remove_new = xiic_i2c_remove, + .driver = { + .name = DRIVER_NAME, + .of_match_table = of_match_ptr(xiic_of_match), + .pm = &xiic_dev_pm_ops, + }, +}; + +module_platform_driver(xiic_i2c_driver); + +MODULE_ALIAS("platform:" DRIVER_NAME); +MODULE_AUTHOR("info@mocean-labs.com"); +MODULE_DESCRIPTION("Xilinx I2C bus driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-xlp9xx.c b/drivers/i2c/busses/i2c-xlp9xx.c new file mode 100644 index 000000000..08a59a920 --- /dev/null +++ b/drivers/i2c/busses/i2c-xlp9xx.c @@ -0,0 +1,593 @@ +/* + * Copyright (c) 2003-2015 Broadcom Corporation + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/acpi.h> +#include <linux/clk.h> +#include <linux/completion.h> +#include <linux/i2c.h> +#include <linux/i2c-smbus.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/delay.h> + +#define XLP9XX_I2C_DIV 0x0 +#define XLP9XX_I2C_CTRL 0x1 +#define XLP9XX_I2C_CMD 0x2 +#define XLP9XX_I2C_STATUS 0x3 +#define XLP9XX_I2C_MTXFIFO 0x4 +#define XLP9XX_I2C_MRXFIFO 0x5 +#define XLP9XX_I2C_MFIFOCTRL 0x6 +#define XLP9XX_I2C_STXFIFO 0x7 +#define XLP9XX_I2C_SRXFIFO 0x8 +#define XLP9XX_I2C_SFIFOCTRL 0x9 +#define XLP9XX_I2C_SLAVEADDR 0xA +#define XLP9XX_I2C_OWNADDR 0xB +#define XLP9XX_I2C_FIFOWCNT 0xC +#define XLP9XX_I2C_INTEN 0xD +#define XLP9XX_I2C_INTST 0xE +#define XLP9XX_I2C_WAITCNT 0xF +#define XLP9XX_I2C_TIMEOUT 0X10 +#define XLP9XX_I2C_GENCALLADDR 0x11 + +#define XLP9XX_I2C_STATUS_BUSY BIT(0) + +#define XLP9XX_I2C_CMD_START BIT(7) +#define XLP9XX_I2C_CMD_STOP BIT(6) +#define XLP9XX_I2C_CMD_READ BIT(5) +#define XLP9XX_I2C_CMD_WRITE BIT(4) +#define XLP9XX_I2C_CMD_ACK BIT(3) + +#define XLP9XX_I2C_CTRL_MCTLEN_SHIFT 16 +#define XLP9XX_I2C_CTRL_MCTLEN_MASK 0xffff0000 +#define XLP9XX_I2C_CTRL_RST BIT(8) +#define XLP9XX_I2C_CTRL_EN BIT(6) +#define XLP9XX_I2C_CTRL_MASTER BIT(4) +#define XLP9XX_I2C_CTRL_FIFORD BIT(1) +#define XLP9XX_I2C_CTRL_ADDMODE BIT(0) + +#define XLP9XX_I2C_INTEN_NACKADDR BIT(25) +#define XLP9XX_I2C_INTEN_SADDR BIT(13) +#define XLP9XX_I2C_INTEN_DATADONE BIT(12) +#define XLP9XX_I2C_INTEN_ARLOST BIT(11) +#define XLP9XX_I2C_INTEN_MFIFOFULL BIT(4) +#define XLP9XX_I2C_INTEN_MFIFOEMTY BIT(3) +#define XLP9XX_I2C_INTEN_MFIFOHI BIT(2) +#define XLP9XX_I2C_INTEN_BUSERR BIT(0) + +#define XLP9XX_I2C_MFIFOCTRL_HITH_SHIFT 8 +#define XLP9XX_I2C_MFIFOCTRL_LOTH_SHIFT 0 +#define XLP9XX_I2C_MFIFOCTRL_RST BIT(16) + +#define XLP9XX_I2C_SLAVEADDR_RW BIT(0) +#define XLP9XX_I2C_SLAVEADDR_ADDR_SHIFT 1 + +#define XLP9XX_I2C_IP_CLK_FREQ 133000000UL +#define XLP9XX_I2C_FIFO_SIZE 0x80U +#define XLP9XX_I2C_TIMEOUT_MS 1000 +#define XLP9XX_I2C_BUSY_TIMEOUT 50 + +#define XLP9XX_I2C_FIFO_WCNT_MASK 0xff +#define XLP9XX_I2C_STATUS_ERRMASK (XLP9XX_I2C_INTEN_ARLOST | \ + XLP9XX_I2C_INTEN_NACKADDR | XLP9XX_I2C_INTEN_BUSERR) + +struct xlp9xx_i2c_dev { + struct device *dev; + struct i2c_adapter adapter; + struct completion msg_complete; + struct i2c_smbus_alert_setup alert_data; + struct i2c_client *ara; + int irq; + bool msg_read; + bool len_recv; + bool client_pec; + u32 __iomem *base; + u32 msg_buf_remaining; + u32 msg_len; + u32 ip_clk_hz; + u32 clk_hz; + u32 msg_err; + u8 *msg_buf; +}; + +static inline void xlp9xx_write_i2c_reg(struct xlp9xx_i2c_dev *priv, + unsigned long reg, u32 val) +{ + writel(val, priv->base + reg); +} + +static inline u32 xlp9xx_read_i2c_reg(struct xlp9xx_i2c_dev *priv, + unsigned long reg) +{ + return readl(priv->base + reg); +} + +static void xlp9xx_i2c_mask_irq(struct xlp9xx_i2c_dev *priv, u32 mask) +{ + u32 inten; + + inten = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_INTEN) & ~mask; + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, inten); +} + +static void xlp9xx_i2c_unmask_irq(struct xlp9xx_i2c_dev *priv, u32 mask) +{ + u32 inten; + + inten = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_INTEN) | mask; + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, inten); +} + +static void xlp9xx_i2c_update_rx_fifo_thres(struct xlp9xx_i2c_dev *priv) +{ + u32 thres; + + if (priv->len_recv) + /* interrupt after the first read to examine + * the length byte before proceeding further + */ + thres = 1; + else if (priv->msg_buf_remaining > XLP9XX_I2C_FIFO_SIZE) + thres = XLP9XX_I2C_FIFO_SIZE; + else + thres = priv->msg_buf_remaining; + + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_MFIFOCTRL, + thres << XLP9XX_I2C_MFIFOCTRL_HITH_SHIFT); +} + +static void xlp9xx_i2c_fill_tx_fifo(struct xlp9xx_i2c_dev *priv) +{ + u32 len, i; + u8 *buf = priv->msg_buf; + + len = min(priv->msg_buf_remaining, XLP9XX_I2C_FIFO_SIZE); + for (i = 0; i < len; i++) + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_MTXFIFO, buf[i]); + priv->msg_buf_remaining -= len; + priv->msg_buf += len; +} + +static void xlp9xx_i2c_update_rlen(struct xlp9xx_i2c_dev *priv) +{ + u32 val, len; + + /* + * Update receive length. Re-read len to get the latest value, + * and then add 4 to have a minimum value that can be safely + * written. This is to account for the byte read above, the + * transfer in progress and any delays in the register I/O + */ + val = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_CTRL); + len = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_FIFOWCNT) & + XLP9XX_I2C_FIFO_WCNT_MASK; + len = max_t(u32, priv->msg_len, len + 4); + if (len >= I2C_SMBUS_BLOCK_MAX + 2) + return; + val = (val & ~XLP9XX_I2C_CTRL_MCTLEN_MASK) | + (len << XLP9XX_I2C_CTRL_MCTLEN_SHIFT); + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, val); +} + +static void xlp9xx_i2c_drain_rx_fifo(struct xlp9xx_i2c_dev *priv) +{ + u32 len, i; + u8 rlen, *buf = priv->msg_buf; + + len = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_FIFOWCNT) & + XLP9XX_I2C_FIFO_WCNT_MASK; + if (!len) + return; + if (priv->len_recv) { + /* read length byte */ + rlen = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_MRXFIFO); + + /* + * We expect at least 2 interrupts for I2C_M_RECV_LEN + * transactions. The length is updated during the first + * interrupt, and the buffer contents are only copied + * during subsequent interrupts. If in case the interrupts + * get merged we would complete the transaction without + * copying out the bytes from RX fifo. To avoid this now we + * drain the fifo as and when data is available. + * We drained the rlen byte already, decrement total length + * by one. + */ + + len--; + if (rlen > I2C_SMBUS_BLOCK_MAX || rlen == 0) { + rlen = 0; /*abort transfer */ + priv->msg_buf_remaining = 0; + priv->msg_len = 0; + xlp9xx_i2c_update_rlen(priv); + return; + } + + *buf++ = rlen; + if (priv->client_pec) + ++rlen; /* account for error check byte */ + /* update remaining bytes and message length */ + priv->msg_buf_remaining = rlen; + priv->msg_len = rlen + 1; + xlp9xx_i2c_update_rlen(priv); + priv->len_recv = false; + } + + len = min(priv->msg_buf_remaining, len); + for (i = 0; i < len; i++, buf++) + *buf = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_MRXFIFO); + + priv->msg_buf_remaining -= len; + priv->msg_buf = buf; + + if (priv->msg_buf_remaining) + xlp9xx_i2c_update_rx_fifo_thres(priv); +} + +static irqreturn_t xlp9xx_i2c_isr(int irq, void *dev_id) +{ + struct xlp9xx_i2c_dev *priv = dev_id; + u32 status; + + status = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_INTST); + if (status == 0) + return IRQ_NONE; + + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTST, status); + if (status & XLP9XX_I2C_STATUS_ERRMASK) { + priv->msg_err = status; + goto xfer_done; + } + + /* SADDR ACK for SMBUS_QUICK */ + if ((status & XLP9XX_I2C_INTEN_SADDR) && (priv->msg_len == 0)) + goto xfer_done; + + if (!priv->msg_read) { + if (status & XLP9XX_I2C_INTEN_MFIFOEMTY) { + /* TX FIFO got empty, fill it up again */ + if (priv->msg_buf_remaining) + xlp9xx_i2c_fill_tx_fifo(priv); + else + xlp9xx_i2c_mask_irq(priv, + XLP9XX_I2C_INTEN_MFIFOEMTY); + } + } else { + if (status & (XLP9XX_I2C_INTEN_DATADONE | + XLP9XX_I2C_INTEN_MFIFOHI)) { + /* data is in FIFO, read it */ + if (priv->msg_buf_remaining) + xlp9xx_i2c_drain_rx_fifo(priv); + } + } + + /* Transfer complete */ + if (status & XLP9XX_I2C_INTEN_DATADONE) + goto xfer_done; + + return IRQ_HANDLED; + +xfer_done: + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, 0); + complete(&priv->msg_complete); + return IRQ_HANDLED; +} + +static int xlp9xx_i2c_check_bus_status(struct xlp9xx_i2c_dev *priv) +{ + u32 status; + u32 busy_timeout = XLP9XX_I2C_BUSY_TIMEOUT; + + while (busy_timeout) { + status = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_STATUS); + if ((status & XLP9XX_I2C_STATUS_BUSY) == 0) + break; + + busy_timeout--; + usleep_range(1000, 1100); + } + + if (!busy_timeout) + return -EIO; + + return 0; +} + +static int xlp9xx_i2c_init(struct xlp9xx_i2c_dev *priv) +{ + u32 prescale; + + /* + * The controller uses 5 * SCL clock internally. + * So prescale value should be divided by 5. + */ + prescale = DIV_ROUND_UP(priv->ip_clk_hz, priv->clk_hz); + prescale = ((prescale - 8) / 5) - 1; + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, XLP9XX_I2C_CTRL_RST); + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, XLP9XX_I2C_CTRL_EN | + XLP9XX_I2C_CTRL_MASTER); + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_DIV, prescale); + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, 0); + + return 0; +} + +static int xlp9xx_i2c_xfer_msg(struct xlp9xx_i2c_dev *priv, struct i2c_msg *msg, + int last_msg) +{ + unsigned long timeleft; + u32 intr_mask, cmd, val, len; + + priv->msg_buf = msg->buf; + priv->msg_buf_remaining = priv->msg_len = msg->len; + priv->msg_err = 0; + priv->msg_read = (msg->flags & I2C_M_RD); + reinit_completion(&priv->msg_complete); + + /* Reset FIFO */ + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_MFIFOCTRL, + XLP9XX_I2C_MFIFOCTRL_RST); + + /* set slave addr */ + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_SLAVEADDR, + (msg->addr << XLP9XX_I2C_SLAVEADDR_ADDR_SHIFT) | + (priv->msg_read ? XLP9XX_I2C_SLAVEADDR_RW : 0)); + + /* Build control word for transfer */ + val = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_CTRL); + if (!priv->msg_read) + val &= ~XLP9XX_I2C_CTRL_FIFORD; + else + val |= XLP9XX_I2C_CTRL_FIFORD; /* read */ + + if (msg->flags & I2C_M_TEN) + val |= XLP9XX_I2C_CTRL_ADDMODE; /* 10-bit address mode*/ + else + val &= ~XLP9XX_I2C_CTRL_ADDMODE; + + priv->len_recv = msg->flags & I2C_M_RECV_LEN; + len = priv->len_recv ? I2C_SMBUS_BLOCK_MAX + 2 : msg->len; + priv->client_pec = msg->flags & I2C_CLIENT_PEC; + + /* set FIFO threshold if reading */ + if (priv->msg_read) + xlp9xx_i2c_update_rx_fifo_thres(priv); + + /* set data length to be transferred */ + val = (val & ~XLP9XX_I2C_CTRL_MCTLEN_MASK) | + (len << XLP9XX_I2C_CTRL_MCTLEN_SHIFT); + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, val); + + /* fill fifo during tx */ + if (!priv->msg_read) + xlp9xx_i2c_fill_tx_fifo(priv); + + /* set interrupt mask */ + intr_mask = (XLP9XX_I2C_INTEN_ARLOST | XLP9XX_I2C_INTEN_BUSERR | + XLP9XX_I2C_INTEN_NACKADDR | XLP9XX_I2C_INTEN_DATADONE); + + if (priv->msg_read) { + intr_mask |= XLP9XX_I2C_INTEN_MFIFOHI; + if (msg->len == 0) + intr_mask |= XLP9XX_I2C_INTEN_SADDR; + } else { + if (msg->len == 0) + intr_mask |= XLP9XX_I2C_INTEN_SADDR; + else + intr_mask |= XLP9XX_I2C_INTEN_MFIFOEMTY; + } + xlp9xx_i2c_unmask_irq(priv, intr_mask); + + /* set cmd reg */ + cmd = XLP9XX_I2C_CMD_START; + if (msg->len) + cmd |= (priv->msg_read ? + XLP9XX_I2C_CMD_READ : XLP9XX_I2C_CMD_WRITE); + if (last_msg) + cmd |= XLP9XX_I2C_CMD_STOP; + + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CMD, cmd); + + timeleft = msecs_to_jiffies(XLP9XX_I2C_TIMEOUT_MS); + timeleft = wait_for_completion_timeout(&priv->msg_complete, timeleft); + + if (priv->msg_err & XLP9XX_I2C_INTEN_BUSERR) { + dev_dbg(priv->dev, "transfer error %x!\n", priv->msg_err); + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CMD, XLP9XX_I2C_CMD_STOP); + return -EIO; + } else if (priv->msg_err & XLP9XX_I2C_INTEN_NACKADDR) { + return -ENXIO; + } + + if (timeleft == 0) { + dev_dbg(priv->dev, "i2c transfer timed out!\n"); + xlp9xx_i2c_init(priv); + return -ETIMEDOUT; + } + + /* update msg->len with actual received length */ + if (msg->flags & I2C_M_RECV_LEN) { + if (!priv->msg_len) + return -EPROTO; + msg->len = priv->msg_len; + } + return 0; +} + +static int xlp9xx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + int i, ret; + struct xlp9xx_i2c_dev *priv = i2c_get_adapdata(adap); + + ret = xlp9xx_i2c_check_bus_status(priv); + if (ret) { + xlp9xx_i2c_init(priv); + ret = xlp9xx_i2c_check_bus_status(priv); + if (ret) + return ret; + } + + for (i = 0; i < num; i++) { + ret = xlp9xx_i2c_xfer_msg(priv, &msgs[i], i == num - 1); + if (ret != 0) + return ret; + } + + return num; +} + +static u32 xlp9xx_i2c_functionality(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_READ_BLOCK_DATA | + I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR; +} + +static const struct i2c_algorithm xlp9xx_i2c_algo = { + .master_xfer = xlp9xx_i2c_xfer, + .functionality = xlp9xx_i2c_functionality, +}; + +static int xlp9xx_i2c_get_frequency(struct platform_device *pdev, + struct xlp9xx_i2c_dev *priv) +{ + struct clk *clk; + u32 freq; + int err; + + clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(clk)) { + priv->ip_clk_hz = XLP9XX_I2C_IP_CLK_FREQ; + dev_dbg(&pdev->dev, "using default input frequency %u\n", + priv->ip_clk_hz); + } else { + priv->ip_clk_hz = clk_get_rate(clk); + } + + err = device_property_read_u32(&pdev->dev, "clock-frequency", &freq); + if (err) { + freq = I2C_MAX_STANDARD_MODE_FREQ; + dev_dbg(&pdev->dev, "using default frequency %u\n", freq); + } else if (freq == 0 || freq > I2C_MAX_FAST_MODE_FREQ) { + dev_warn(&pdev->dev, "invalid frequency %u, using default\n", + freq); + freq = I2C_MAX_STANDARD_MODE_FREQ; + } + priv->clk_hz = freq; + + return 0; +} + +static int xlp9xx_i2c_smbus_setup(struct xlp9xx_i2c_dev *priv, + struct platform_device *pdev) +{ + struct i2c_client *ara; + + if (!priv->alert_data.irq) + return -EINVAL; + + ara = i2c_new_smbus_alert_device(&priv->adapter, &priv->alert_data); + if (IS_ERR(ara)) + return PTR_ERR(ara); + + priv->ara = ara; + + return 0; +} + +static int xlp9xx_i2c_probe(struct platform_device *pdev) +{ + struct xlp9xx_i2c_dev *priv; + int err = 0; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->base)) + return PTR_ERR(priv->base); + + priv->irq = platform_get_irq(pdev, 0); + if (priv->irq < 0) + return priv->irq; + /* SMBAlert irq */ + priv->alert_data.irq = platform_get_irq(pdev, 1); + if (priv->alert_data.irq <= 0) + priv->alert_data.irq = 0; + + xlp9xx_i2c_get_frequency(pdev, priv); + xlp9xx_i2c_init(priv); + + err = devm_request_irq(&pdev->dev, priv->irq, xlp9xx_i2c_isr, 0, + pdev->name, priv); + if (err) + return dev_err_probe(&pdev->dev, err, "IRQ request failed!\n"); + + init_completion(&priv->msg_complete); + priv->adapter.dev.parent = &pdev->dev; + priv->adapter.algo = &xlp9xx_i2c_algo; + priv->adapter.class = I2C_CLASS_HWMON; + ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&pdev->dev)); + priv->adapter.dev.of_node = pdev->dev.of_node; + priv->dev = &pdev->dev; + + snprintf(priv->adapter.name, sizeof(priv->adapter.name), "xlp9xx-i2c"); + i2c_set_adapdata(&priv->adapter, priv); + + err = i2c_add_adapter(&priv->adapter); + if (err) + return err; + + err = xlp9xx_i2c_smbus_setup(priv, pdev); + if (err) + dev_dbg(&pdev->dev, "No active SMBus alert %d\n", err); + + platform_set_drvdata(pdev, priv); + dev_dbg(&pdev->dev, "I2C bus:%d added\n", priv->adapter.nr); + + return 0; +} + +static void xlp9xx_i2c_remove(struct platform_device *pdev) +{ + struct xlp9xx_i2c_dev *priv; + + priv = platform_get_drvdata(pdev); + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, 0); + synchronize_irq(priv->irq); + i2c_del_adapter(&priv->adapter); + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, 0); +} + +#ifdef CONFIG_ACPI +static const struct acpi_device_id xlp9xx_i2c_acpi_ids[] = { + {"BRCM9007", 0}, + {"CAV9007", 0}, + {} +}; +MODULE_DEVICE_TABLE(acpi, xlp9xx_i2c_acpi_ids); +#endif + +static struct platform_driver xlp9xx_i2c_driver = { + .probe = xlp9xx_i2c_probe, + .remove_new = xlp9xx_i2c_remove, + .driver = { + .name = "xlp9xx-i2c", + .acpi_match_table = ACPI_PTR(xlp9xx_i2c_acpi_ids), + }, +}; + +module_platform_driver(xlp9xx_i2c_driver); + +MODULE_AUTHOR("Subhendu Sekhar Behera <sbehera@broadcom.com>"); +MODULE_DESCRIPTION("XLP9XX/5XX I2C Bus Controller Driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/scx200_acb.c b/drivers/i2c/busses/scx200_acb.c new file mode 100644 index 000000000..83c1db610 --- /dev/null +++ b/drivers/i2c/busses/scx200_acb.c @@ -0,0 +1,598 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com> + + National Semiconductor SCx200 ACCESS.bus support + Also supports the AMD CS5535 and AMD CS5536 + + Based on i2c-keywest.c which is: + Copyright (c) 2001 Benjamin Herrenschmidt <benh@kernel.crashing.org> + Copyright (c) 2000 Philip Edelbrock <phil@stimpy.netroedge.com> + +*/ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/pci.h> +#include <linux/platform_device.h> +#include <linux/delay.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/io.h> + +#include <linux/scx200.h> + +MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>"); +MODULE_DESCRIPTION("NatSemi SCx200 ACCESS.bus Driver"); +MODULE_ALIAS("platform:cs5535-smb"); +MODULE_LICENSE("GPL"); + +#define MAX_DEVICES 4 +static int base[MAX_DEVICES] = { 0x820, 0x840 }; +module_param_hw_array(base, int, ioport, NULL, 0); +MODULE_PARM_DESC(base, "Base addresses for the ACCESS.bus controllers"); + +#define POLL_TIMEOUT (HZ/5) + +enum scx200_acb_state { + state_idle, + state_address, + state_command, + state_repeat_start, + state_quick, + state_read, + state_write, +}; + +static const char *scx200_acb_state_name[] = { + "idle", + "address", + "command", + "repeat_start", + "quick", + "read", + "write", +}; + +/* Physical interface */ +struct scx200_acb_iface { + struct scx200_acb_iface *next; + struct i2c_adapter adapter; + unsigned base; + struct mutex mutex; + + /* State machine data */ + enum scx200_acb_state state; + int result; + u8 address_byte; + u8 command; + u8 *ptr; + char needs_reset; + unsigned len; +}; + +/* Register Definitions */ +#define ACBSDA (iface->base + 0) +#define ACBST (iface->base + 1) +#define ACBST_SDAST 0x40 /* SDA Status */ +#define ACBST_BER 0x20 +#define ACBST_NEGACK 0x10 /* Negative Acknowledge */ +#define ACBST_STASTR 0x08 /* Stall After Start */ +#define ACBST_MASTER 0x02 +#define ACBCST (iface->base + 2) +#define ACBCST_BB 0x02 +#define ACBCTL1 (iface->base + 3) +#define ACBCTL1_STASTRE 0x80 +#define ACBCTL1_NMINTE 0x40 +#define ACBCTL1_ACK 0x10 +#define ACBCTL1_STOP 0x02 +#define ACBCTL1_START 0x01 +#define ACBADDR (iface->base + 4) +#define ACBCTL2 (iface->base + 5) +#define ACBCTL2_ENABLE 0x01 + +/************************************************************************/ + +static void scx200_acb_machine(struct scx200_acb_iface *iface, u8 status) +{ + const char *errmsg; + + dev_dbg(&iface->adapter.dev, "state %s, status = 0x%02x\n", + scx200_acb_state_name[iface->state], status); + + if (status & ACBST_BER) { + errmsg = "bus error"; + goto error; + } + if (!(status & ACBST_MASTER)) { + errmsg = "not master"; + goto error; + } + if (status & ACBST_NEGACK) { + dev_dbg(&iface->adapter.dev, "negative ack in state %s\n", + scx200_acb_state_name[iface->state]); + + iface->state = state_idle; + iface->result = -ENXIO; + + outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1); + outb(ACBST_STASTR | ACBST_NEGACK, ACBST); + + /* Reset the status register */ + outb(0, ACBST); + return; + } + + switch (iface->state) { + case state_idle: + dev_warn(&iface->adapter.dev, "interrupt in idle state\n"); + break; + + case state_address: + /* Do a pointer write first */ + outb(iface->address_byte & ~1, ACBSDA); + + iface->state = state_command; + break; + + case state_command: + outb(iface->command, ACBSDA); + + if (iface->address_byte & 1) + iface->state = state_repeat_start; + else + iface->state = state_write; + break; + + case state_repeat_start: + outb(inb(ACBCTL1) | ACBCTL1_START, ACBCTL1); + fallthrough; + + case state_quick: + if (iface->address_byte & 1) { + if (iface->len == 1) + outb(inb(ACBCTL1) | ACBCTL1_ACK, ACBCTL1); + else + outb(inb(ACBCTL1) & ~ACBCTL1_ACK, ACBCTL1); + outb(iface->address_byte, ACBSDA); + + iface->state = state_read; + } else { + outb(iface->address_byte, ACBSDA); + + iface->state = state_write; + } + break; + + case state_read: + /* Set ACK if _next_ byte will be the last one */ + if (iface->len == 2) + outb(inb(ACBCTL1) | ACBCTL1_ACK, ACBCTL1); + else + outb(inb(ACBCTL1) & ~ACBCTL1_ACK, ACBCTL1); + + if (iface->len == 1) { + iface->result = 0; + iface->state = state_idle; + outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1); + } + + *iface->ptr++ = inb(ACBSDA); + --iface->len; + + break; + + case state_write: + if (iface->len == 0) { + iface->result = 0; + iface->state = state_idle; + outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1); + break; + } + + outb(*iface->ptr++, ACBSDA); + --iface->len; + + break; + } + + return; + + error: + dev_err(&iface->adapter.dev, + "%s in state %s (addr=0x%02x, len=%d, status=0x%02x)\n", errmsg, + scx200_acb_state_name[iface->state], iface->address_byte, + iface->len, status); + + iface->state = state_idle; + iface->result = -EIO; + iface->needs_reset = 1; +} + +static void scx200_acb_poll(struct scx200_acb_iface *iface) +{ + u8 status; + unsigned long timeout; + + timeout = jiffies + POLL_TIMEOUT; + while (1) { + status = inb(ACBST); + + /* Reset the status register to avoid the hang */ + outb(0, ACBST); + + if ((status & (ACBST_SDAST|ACBST_BER|ACBST_NEGACK)) != 0) { + scx200_acb_machine(iface, status); + return; + } + if (time_after(jiffies, timeout)) + break; + cpu_relax(); + cond_resched(); + } + + dev_err(&iface->adapter.dev, "timeout in state %s\n", + scx200_acb_state_name[iface->state]); + + iface->state = state_idle; + iface->result = -EIO; + iface->needs_reset = 1; +} + +static void scx200_acb_reset(struct scx200_acb_iface *iface) +{ + /* Disable the ACCESS.bus device and Configure the SCL + frequency: 16 clock cycles */ + outb(0x70, ACBCTL2); + /* Polling mode */ + outb(0, ACBCTL1); + /* Disable slave address */ + outb(0, ACBADDR); + /* Enable the ACCESS.bus device */ + outb(inb(ACBCTL2) | ACBCTL2_ENABLE, ACBCTL2); + /* Free STALL after START */ + outb(inb(ACBCTL1) & ~(ACBCTL1_STASTRE | ACBCTL1_NMINTE), ACBCTL1); + /* Send a STOP */ + outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1); + /* Clear BER, NEGACK and STASTR bits */ + outb(ACBST_BER | ACBST_NEGACK | ACBST_STASTR, ACBST); + /* Clear BB bit */ + outb(inb(ACBCST) | ACBCST_BB, ACBCST); +} + +static s32 scx200_acb_smbus_xfer(struct i2c_adapter *adapter, + u16 address, unsigned short flags, + char rw, u8 command, int size, + union i2c_smbus_data *data) +{ + struct scx200_acb_iface *iface = i2c_get_adapdata(adapter); + int len; + u8 *buffer; + u16 cur_word; + int rc; + + switch (size) { + case I2C_SMBUS_QUICK: + len = 0; + buffer = NULL; + break; + + case I2C_SMBUS_BYTE: + len = 1; + buffer = rw ? &data->byte : &command; + break; + + case I2C_SMBUS_BYTE_DATA: + len = 1; + buffer = &data->byte; + break; + + case I2C_SMBUS_WORD_DATA: + len = 2; + cur_word = cpu_to_le16(data->word); + buffer = (u8 *)&cur_word; + break; + + case I2C_SMBUS_I2C_BLOCK_DATA: + len = data->block[0]; + if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) + return -EINVAL; + buffer = &data->block[1]; + break; + + default: + return -EINVAL; + } + + dev_dbg(&adapter->dev, + "size=%d, address=0x%x, command=0x%x, len=%d, read=%d\n", + size, address, command, len, rw); + + if (!len && rw == I2C_SMBUS_READ) { + dev_dbg(&adapter->dev, "zero length read\n"); + return -EINVAL; + } + + mutex_lock(&iface->mutex); + + iface->address_byte = (address << 1) | rw; + iface->command = command; + iface->ptr = buffer; + iface->len = len; + iface->result = -EINVAL; + iface->needs_reset = 0; + + outb(inb(ACBCTL1) | ACBCTL1_START, ACBCTL1); + + if (size == I2C_SMBUS_QUICK || size == I2C_SMBUS_BYTE) + iface->state = state_quick; + else + iface->state = state_address; + + while (iface->state != state_idle) + scx200_acb_poll(iface); + + if (iface->needs_reset) + scx200_acb_reset(iface); + + rc = iface->result; + + mutex_unlock(&iface->mutex); + + if (rc == 0 && size == I2C_SMBUS_WORD_DATA && rw == I2C_SMBUS_READ) + data->word = le16_to_cpu(cur_word); + +#ifdef DEBUG + dev_dbg(&adapter->dev, "transfer done, result: %d", rc); + if (buffer) { + int i; + printk(" data:"); + for (i = 0; i < len; ++i) + printk(" %02x", buffer[i]); + } + printk("\n"); +#endif + + return rc; +} + +static u32 scx200_acb_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_I2C_BLOCK; +} + +/* For now, we only handle combined mode (smbus) */ +static const struct i2c_algorithm scx200_acb_algorithm = { + .smbus_xfer = scx200_acb_smbus_xfer, + .functionality = scx200_acb_func, +}; + +static struct scx200_acb_iface *scx200_acb_list; +static DEFINE_MUTEX(scx200_acb_list_mutex); + +static int scx200_acb_probe(struct scx200_acb_iface *iface) +{ + u8 val; + + /* Disable the ACCESS.bus device and Configure the SCL + frequency: 16 clock cycles */ + outb(0x70, ACBCTL2); + + if (inb(ACBCTL2) != 0x70) { + pr_debug("ACBCTL2 readback failed\n"); + return -ENXIO; + } + + outb(inb(ACBCTL1) | ACBCTL1_NMINTE, ACBCTL1); + + val = inb(ACBCTL1); + if (val) { + pr_debug("disabled, but ACBCTL1=0x%02x\n", val); + return -ENXIO; + } + + outb(inb(ACBCTL2) | ACBCTL2_ENABLE, ACBCTL2); + + outb(inb(ACBCTL1) | ACBCTL1_NMINTE, ACBCTL1); + + val = inb(ACBCTL1); + if ((val & ACBCTL1_NMINTE) != ACBCTL1_NMINTE) { + pr_debug("enabled, but NMINTE won't be set, ACBCTL1=0x%02x\n", + val); + return -ENXIO; + } + + return 0; +} + +static struct scx200_acb_iface *scx200_create_iface(const char *text, + struct device *dev, int index) +{ + struct scx200_acb_iface *iface; + struct i2c_adapter *adapter; + + iface = kzalloc(sizeof(*iface), GFP_KERNEL); + if (!iface) + return NULL; + + adapter = &iface->adapter; + i2c_set_adapdata(adapter, iface); + snprintf(adapter->name, sizeof(adapter->name), "%s ACB%d", text, index); + adapter->owner = THIS_MODULE; + adapter->algo = &scx200_acb_algorithm; + adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + adapter->dev.parent = dev; + + mutex_init(&iface->mutex); + + return iface; +} + +static int scx200_acb_create(struct scx200_acb_iface *iface) +{ + struct i2c_adapter *adapter; + int rc; + + adapter = &iface->adapter; + + rc = scx200_acb_probe(iface); + if (rc) { + pr_warn("probe failed\n"); + return rc; + } + + scx200_acb_reset(iface); + + if (i2c_add_adapter(adapter) < 0) { + pr_err("failed to register\n"); + return -ENODEV; + } + + if (!adapter->dev.parent) { + /* If there's no dev, we're tracking (ISA) ifaces manually */ + mutex_lock(&scx200_acb_list_mutex); + iface->next = scx200_acb_list; + scx200_acb_list = iface; + mutex_unlock(&scx200_acb_list_mutex); + } + + return 0; +} + +static struct scx200_acb_iface *scx200_create_dev(const char *text, + unsigned long base, int index, struct device *dev) +{ + struct scx200_acb_iface *iface; + int rc; + + iface = scx200_create_iface(text, dev, index); + + if (iface == NULL) + return NULL; + + if (!request_region(base, 8, iface->adapter.name)) { + pr_err("can't allocate io 0x%lx-0x%lx\n", base, base + 8 - 1); + goto errout_free; + } + + iface->base = base; + rc = scx200_acb_create(iface); + + if (rc == 0) + return iface; + + release_region(base, 8); + errout_free: + kfree(iface); + return NULL; +} + +static int scx200_probe(struct platform_device *pdev) +{ + struct scx200_acb_iface *iface; + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_IO, 0); + if (!res) { + dev_err(&pdev->dev, "can't fetch device resource info\n"); + return -ENODEV; + } + + iface = scx200_create_dev("CS5535", res->start, 0, &pdev->dev); + if (!iface) + return -EIO; + + dev_info(&pdev->dev, "SCx200 device '%s' registered\n", + iface->adapter.name); + platform_set_drvdata(pdev, iface); + + return 0; +} + +static void scx200_cleanup_iface(struct scx200_acb_iface *iface) +{ + i2c_del_adapter(&iface->adapter); + release_region(iface->base, 8); + kfree(iface); +} + +static void scx200_remove(struct platform_device *pdev) +{ + struct scx200_acb_iface *iface; + + iface = platform_get_drvdata(pdev); + scx200_cleanup_iface(iface); +} + +static struct platform_driver scx200_pci_driver = { + .driver = { + .name = "cs5535-smb", + }, + .probe = scx200_probe, + .remove_new = scx200_remove, +}; + +static const struct pci_device_id scx200_isa[] = { + { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SCx200_BRIDGE) }, + { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE) }, + { 0, } +}; + +static __init void scx200_scan_isa(void) +{ + int i; + + if (!pci_dev_present(scx200_isa)) + return; + + for (i = 0; i < MAX_DEVICES; ++i) { + if (base[i] == 0) + continue; + + /* XXX: should we care about failures? */ + scx200_create_dev("SCx200", base[i], i, NULL); + } +} + +static int __init scx200_acb_init(void) +{ + pr_debug("NatSemi SCx200 ACCESS.bus Driver\n"); + + /* First scan for ISA-based devices */ + scx200_scan_isa(); /* XXX: should we care about errors? */ + + /* If at least one bus was created, init must succeed */ + if (scx200_acb_list) + return 0; + + /* No ISA devices; register the platform driver for PCI-based devices */ + return platform_driver_register(&scx200_pci_driver); +} + +static void __exit scx200_acb_cleanup(void) +{ + struct scx200_acb_iface *iface; + + platform_driver_unregister(&scx200_pci_driver); + + mutex_lock(&scx200_acb_list_mutex); + while ((iface = scx200_acb_list) != NULL) { + scx200_acb_list = iface->next; + mutex_unlock(&scx200_acb_list_mutex); + + scx200_cleanup_iface(iface); + + mutex_lock(&scx200_acb_list_mutex); + } + mutex_unlock(&scx200_acb_list_mutex); +} + +module_init(scx200_acb_init); +module_exit(scx200_acb_cleanup); diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c new file mode 100644 index 000000000..8ca1daade --- /dev/null +++ b/drivers/i2c/i2c-atr.c @@ -0,0 +1,710 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * I2C Address Translator + * + * Copyright (c) 2019,2022 Luca Ceresoli <luca@lucaceresoli.net> + * Copyright (c) 2022,2023 Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> + * + * Originally based on i2c-mux.c + */ + +#include <linux/fwnode.h> +#include <linux/i2c-atr.h> +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +#define ATR_MAX_ADAPTERS 100 /* Just a sanity limit */ +#define ATR_MAX_SYMLINK_LEN 11 /* Longest name is 10 chars: "channel-99" */ + +/** + * struct i2c_atr_alias_pair - Holds the alias assigned to a client. + * @node: List node + * @client: Pointer to the client on the child bus + * @alias: I2C alias address assigned by the driver. + * This is the address that will be used to issue I2C transactions + * on the parent (physical) bus. + */ +struct i2c_atr_alias_pair { + struct list_head node; + const struct i2c_client *client; + u16 alias; +}; + +/** + * struct i2c_atr_chan - Data for a channel. + * @adap: The &struct i2c_adapter for the channel + * @atr: The parent I2C ATR + * @chan_id: The ID of this channel + * @alias_list: List of @struct i2c_atr_alias_pair containing the + * assigned aliases + * @orig_addrs_lock: Mutex protecting @orig_addrs + * @orig_addrs: Buffer used to store the original addresses during transmit + * @orig_addrs_size: Size of @orig_addrs + */ +struct i2c_atr_chan { + struct i2c_adapter adap; + struct i2c_atr *atr; + u32 chan_id; + + struct list_head alias_list; + + /* Lock orig_addrs during xfer */ + struct mutex orig_addrs_lock; + u16 *orig_addrs; + unsigned int orig_addrs_size; +}; + +/** + * struct i2c_atr - The I2C ATR instance + * @parent: The parent &struct i2c_adapter + * @dev: The device that owns the I2C ATR instance + * @ops: &struct i2c_atr_ops + * @priv: Private driver data, set with i2c_atr_set_driver_data() + * @algo: The &struct i2c_algorithm for adapters + * @lock: Lock for the I2C bus segment (see &struct i2c_lock_operations) + * @max_adapters: Maximum number of adapters this I2C ATR can have + * @num_aliases: Number of aliases in the aliases array + * @aliases: The aliases array + * @alias_mask_lock: Lock protecting alias_use_mask + * @alias_use_mask: Bitmask for used aliases in aliases array + * @i2c_nb: Notifier for remote client add & del events + * @adapter: Array of adapters + */ +struct i2c_atr { + struct i2c_adapter *parent; + struct device *dev; + const struct i2c_atr_ops *ops; + + void *priv; + + struct i2c_algorithm algo; + /* lock for the I2C bus segment (see struct i2c_lock_operations) */ + struct mutex lock; + int max_adapters; + + size_t num_aliases; + const u16 *aliases; + /* Protects alias_use_mask */ + spinlock_t alias_mask_lock; + unsigned long *alias_use_mask; + + struct notifier_block i2c_nb; + + struct i2c_adapter *adapter[]; +}; + +static struct i2c_atr_alias_pair * +i2c_atr_find_mapping_by_client(const struct list_head *list, + const struct i2c_client *client) +{ + struct i2c_atr_alias_pair *c2a; + + list_for_each_entry(c2a, list, node) { + if (c2a->client == client) + return c2a; + } + + return NULL; +} + +static struct i2c_atr_alias_pair * +i2c_atr_find_mapping_by_addr(const struct list_head *list, u16 phys_addr) +{ + struct i2c_atr_alias_pair *c2a; + + list_for_each_entry(c2a, list, node) { + if (c2a->client->addr == phys_addr) + return c2a; + } + + return NULL; +} + +/* + * Replace all message addresses with their aliases, saving the original + * addresses. + * + * This function is internal for use in i2c_atr_master_xfer(). It must be + * followed by i2c_atr_unmap_msgs() to restore the original addresses. + */ +static int i2c_atr_map_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs, + int num) +{ + struct i2c_atr *atr = chan->atr; + static struct i2c_atr_alias_pair *c2a; + int i; + + /* Ensure we have enough room to save the original addresses */ + if (unlikely(chan->orig_addrs_size < num)) { + u16 *new_buf; + + /* We don't care about old data, hence no realloc() */ + new_buf = kmalloc_array(num, sizeof(*new_buf), GFP_KERNEL); + if (!new_buf) + return -ENOMEM; + + kfree(chan->orig_addrs); + chan->orig_addrs = new_buf; + chan->orig_addrs_size = num; + } + + for (i = 0; i < num; i++) { + chan->orig_addrs[i] = msgs[i].addr; + + c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list, + msgs[i].addr); + if (!c2a) { + dev_err(atr->dev, "client 0x%02x not mapped!\n", + msgs[i].addr); + + while (i--) + msgs[i].addr = chan->orig_addrs[i]; + + return -ENXIO; + } + + msgs[i].addr = c2a->alias; + } + + return 0; +} + +/* + * Restore all message address aliases with the original addresses. This + * function is internal for use in i2c_atr_master_xfer() and for this reason it + * needs no null and size checks on orig_addr. + * + * @see i2c_atr_map_msgs() + */ +static void i2c_atr_unmap_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs, + int num) +{ + int i; + + for (i = 0; i < num; i++) + msgs[i].addr = chan->orig_addrs[i]; +} + +static int i2c_atr_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + struct i2c_atr_chan *chan = adap->algo_data; + struct i2c_atr *atr = chan->atr; + struct i2c_adapter *parent = atr->parent; + int ret; + + /* Translate addresses */ + mutex_lock(&chan->orig_addrs_lock); + + ret = i2c_atr_map_msgs(chan, msgs, num); + if (ret < 0) + goto err_unlock; + + /* Perform the transfer */ + ret = i2c_transfer(parent, msgs, num); + + /* Restore addresses */ + i2c_atr_unmap_msgs(chan, msgs, num); + +err_unlock: + mutex_unlock(&chan->orig_addrs_lock); + + return ret; +} + +static int i2c_atr_smbus_xfer(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, u8 command, + int size, union i2c_smbus_data *data) +{ + struct i2c_atr_chan *chan = adap->algo_data; + struct i2c_atr *atr = chan->atr; + struct i2c_adapter *parent = atr->parent; + struct i2c_atr_alias_pair *c2a; + + c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list, addr); + if (!c2a) { + dev_err(atr->dev, "client 0x%02x not mapped!\n", addr); + return -ENXIO; + } + + return i2c_smbus_xfer(parent, c2a->alias, flags, read_write, command, + size, data); +} + +static u32 i2c_atr_functionality(struct i2c_adapter *adap) +{ + struct i2c_atr_chan *chan = adap->algo_data; + struct i2c_adapter *parent = chan->atr->parent; + + return parent->algo->functionality(parent); +} + +static void i2c_atr_lock_bus(struct i2c_adapter *adapter, unsigned int flags) +{ + struct i2c_atr_chan *chan = adapter->algo_data; + struct i2c_atr *atr = chan->atr; + + mutex_lock(&atr->lock); +} + +static int i2c_atr_trylock_bus(struct i2c_adapter *adapter, unsigned int flags) +{ + struct i2c_atr_chan *chan = adapter->algo_data; + struct i2c_atr *atr = chan->atr; + + return mutex_trylock(&atr->lock); +} + +static void i2c_atr_unlock_bus(struct i2c_adapter *adapter, unsigned int flags) +{ + struct i2c_atr_chan *chan = adapter->algo_data; + struct i2c_atr *atr = chan->atr; + + mutex_unlock(&atr->lock); +} + +static const struct i2c_lock_operations i2c_atr_lock_ops = { + .lock_bus = i2c_atr_lock_bus, + .trylock_bus = i2c_atr_trylock_bus, + .unlock_bus = i2c_atr_unlock_bus, +}; + +static int i2c_atr_reserve_alias(struct i2c_atr *atr) +{ + unsigned long idx; + + spin_lock(&atr->alias_mask_lock); + + idx = find_first_zero_bit(atr->alias_use_mask, atr->num_aliases); + if (idx >= atr->num_aliases) { + spin_unlock(&atr->alias_mask_lock); + dev_err(atr->dev, "failed to find a free alias\n"); + return -EBUSY; + } + + set_bit(idx, atr->alias_use_mask); + + spin_unlock(&atr->alias_mask_lock); + + return atr->aliases[idx]; +} + +static void i2c_atr_release_alias(struct i2c_atr *atr, u16 alias) +{ + unsigned int idx; + + spin_lock(&atr->alias_mask_lock); + + for (idx = 0; idx < atr->num_aliases; ++idx) { + if (atr->aliases[idx] == alias) { + clear_bit(idx, atr->alias_use_mask); + spin_unlock(&atr->alias_mask_lock); + return; + } + } + + spin_unlock(&atr->alias_mask_lock); + + /* This should never happen */ + dev_warn(atr->dev, "Unable to find mapped alias\n"); +} + +static int i2c_atr_attach_client(struct i2c_adapter *adapter, + const struct i2c_client *client) +{ + struct i2c_atr_chan *chan = adapter->algo_data; + struct i2c_atr *atr = chan->atr; + struct i2c_atr_alias_pair *c2a; + u16 alias; + int ret; + + ret = i2c_atr_reserve_alias(atr); + if (ret < 0) + return ret; + + alias = ret; + + c2a = kzalloc(sizeof(*c2a), GFP_KERNEL); + if (!c2a) { + ret = -ENOMEM; + goto err_release_alias; + } + + ret = atr->ops->attach_client(atr, chan->chan_id, client, alias); + if (ret) + goto err_free; + + dev_dbg(atr->dev, "chan%u: client 0x%02x mapped at alias 0x%02x (%s)\n", + chan->chan_id, client->addr, alias, client->name); + + c2a->client = client; + c2a->alias = alias; + list_add(&c2a->node, &chan->alias_list); + + return 0; + +err_free: + kfree(c2a); +err_release_alias: + i2c_atr_release_alias(atr, alias); + + return ret; +} + +static void i2c_atr_detach_client(struct i2c_adapter *adapter, + const struct i2c_client *client) +{ + struct i2c_atr_chan *chan = adapter->algo_data; + struct i2c_atr *atr = chan->atr; + struct i2c_atr_alias_pair *c2a; + + atr->ops->detach_client(atr, chan->chan_id, client); + + c2a = i2c_atr_find_mapping_by_client(&chan->alias_list, client); + if (!c2a) { + /* This should never happen */ + dev_warn(atr->dev, "Unable to find address mapping\n"); + return; + } + + i2c_atr_release_alias(atr, c2a->alias); + + dev_dbg(atr->dev, + "chan%u: client 0x%02x unmapped from alias 0x%02x (%s)\n", + chan->chan_id, client->addr, c2a->alias, client->name); + + list_del(&c2a->node); + kfree(c2a); +} + +static int i2c_atr_bus_notifier_call(struct notifier_block *nb, + unsigned long event, void *device) +{ + struct i2c_atr *atr = container_of(nb, struct i2c_atr, i2c_nb); + struct device *dev = device; + struct i2c_client *client; + u32 chan_id; + int ret; + + client = i2c_verify_client(dev); + if (!client) + return NOTIFY_DONE; + + /* Is the client in one of our adapters? */ + for (chan_id = 0; chan_id < atr->max_adapters; ++chan_id) { + if (client->adapter == atr->adapter[chan_id]) + break; + } + + if (chan_id == atr->max_adapters) + return NOTIFY_DONE; + + switch (event) { + case BUS_NOTIFY_ADD_DEVICE: + ret = i2c_atr_attach_client(client->adapter, client); + if (ret) + dev_err(atr->dev, + "Failed to attach remote client '%s': %d\n", + dev_name(dev), ret); + break; + + case BUS_NOTIFY_DEL_DEVICE: + i2c_atr_detach_client(client->adapter, client); + break; + + default: + break; + } + + return NOTIFY_DONE; +} + +static int i2c_atr_parse_alias_pool(struct i2c_atr *atr) +{ + struct device *dev = atr->dev; + unsigned long *alias_use_mask; + size_t num_aliases; + unsigned int i; + u32 *aliases32; + u16 *aliases16; + int ret; + + ret = fwnode_property_count_u32(dev_fwnode(dev), "i2c-alias-pool"); + if (ret < 0) { + dev_err(dev, "Failed to count 'i2c-alias-pool' property: %d\n", + ret); + return ret; + } + + num_aliases = ret; + + if (!num_aliases) + return 0; + + aliases32 = kcalloc(num_aliases, sizeof(*aliases32), GFP_KERNEL); + if (!aliases32) + return -ENOMEM; + + ret = fwnode_property_read_u32_array(dev_fwnode(dev), "i2c-alias-pool", + aliases32, num_aliases); + if (ret < 0) { + dev_err(dev, "Failed to read 'i2c-alias-pool' property: %d\n", + ret); + goto err_free_aliases32; + } + + aliases16 = kcalloc(num_aliases, sizeof(*aliases16), GFP_KERNEL); + if (!aliases16) { + ret = -ENOMEM; + goto err_free_aliases32; + } + + for (i = 0; i < num_aliases; i++) { + if (!(aliases32[i] & 0xffff0000)) { + aliases16[i] = aliases32[i]; + continue; + } + + dev_err(dev, "Failed to parse 'i2c-alias-pool' property: I2C flags are not supported\n"); + ret = -EINVAL; + goto err_free_aliases16; + } + + alias_use_mask = bitmap_zalloc(num_aliases, GFP_KERNEL); + if (!alias_use_mask) { + ret = -ENOMEM; + goto err_free_aliases16; + } + + kfree(aliases32); + + atr->num_aliases = num_aliases; + atr->aliases = aliases16; + atr->alias_use_mask = alias_use_mask; + + dev_dbg(dev, "i2c-alias-pool has %zu aliases", atr->num_aliases); + + return 0; + +err_free_aliases16: + kfree(aliases16); +err_free_aliases32: + kfree(aliases32); + return ret; +} + +struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, + const struct i2c_atr_ops *ops, int max_adapters) +{ + struct i2c_atr *atr; + int ret; + + if (max_adapters > ATR_MAX_ADAPTERS) + return ERR_PTR(-EINVAL); + + if (!ops || !ops->attach_client || !ops->detach_client) + return ERR_PTR(-EINVAL); + + atr = kzalloc(struct_size(atr, adapter, max_adapters), GFP_KERNEL); + if (!atr) + return ERR_PTR(-ENOMEM); + + mutex_init(&atr->lock); + spin_lock_init(&atr->alias_mask_lock); + + atr->parent = parent; + atr->dev = dev; + atr->ops = ops; + atr->max_adapters = max_adapters; + + if (parent->algo->master_xfer) + atr->algo.master_xfer = i2c_atr_master_xfer; + if (parent->algo->smbus_xfer) + atr->algo.smbus_xfer = i2c_atr_smbus_xfer; + atr->algo.functionality = i2c_atr_functionality; + + ret = i2c_atr_parse_alias_pool(atr); + if (ret) + goto err_destroy_mutex; + + atr->i2c_nb.notifier_call = i2c_atr_bus_notifier_call; + ret = bus_register_notifier(&i2c_bus_type, &atr->i2c_nb); + if (ret) + goto err_free_aliases; + + return atr; + +err_free_aliases: + bitmap_free(atr->alias_use_mask); + kfree(atr->aliases); +err_destroy_mutex: + mutex_destroy(&atr->lock); + kfree(atr); + + return ERR_PTR(ret); +} +EXPORT_SYMBOL_NS_GPL(i2c_atr_new, I2C_ATR); + +void i2c_atr_delete(struct i2c_atr *atr) +{ + unsigned int i; + + for (i = 0; i < atr->max_adapters; ++i) + WARN_ON(atr->adapter[i]); + + bus_unregister_notifier(&i2c_bus_type, &atr->i2c_nb); + bitmap_free(atr->alias_use_mask); + kfree(atr->aliases); + mutex_destroy(&atr->lock); + kfree(atr); +} +EXPORT_SYMBOL_NS_GPL(i2c_atr_delete, I2C_ATR); + +int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, + struct device *adapter_parent, + struct fwnode_handle *bus_handle) +{ + struct i2c_adapter *parent = atr->parent; + struct device *dev = atr->dev; + struct i2c_atr_chan *chan; + char symlink_name[ATR_MAX_SYMLINK_LEN]; + int ret; + + if (chan_id >= atr->max_adapters) { + dev_err(dev, "No room for more i2c-atr adapters\n"); + return -EINVAL; + } + + if (atr->adapter[chan_id]) { + dev_err(dev, "Adapter %d already present\n", chan_id); + return -EEXIST; + } + + chan = kzalloc(sizeof(*chan), GFP_KERNEL); + if (!chan) + return -ENOMEM; + + if (!adapter_parent) + adapter_parent = dev; + + chan->atr = atr; + chan->chan_id = chan_id; + INIT_LIST_HEAD(&chan->alias_list); + mutex_init(&chan->orig_addrs_lock); + + snprintf(chan->adap.name, sizeof(chan->adap.name), "i2c-%d-atr-%d", + i2c_adapter_id(parent), chan_id); + chan->adap.owner = THIS_MODULE; + chan->adap.algo = &atr->algo; + chan->adap.algo_data = chan; + chan->adap.dev.parent = adapter_parent; + chan->adap.retries = parent->retries; + chan->adap.timeout = parent->timeout; + chan->adap.quirks = parent->quirks; + chan->adap.lock_ops = &i2c_atr_lock_ops; + + if (bus_handle) { + device_set_node(&chan->adap.dev, fwnode_handle_get(bus_handle)); + } else { + struct fwnode_handle *atr_node; + struct fwnode_handle *child; + u32 reg; + + atr_node = device_get_named_child_node(dev, "i2c-atr"); + + fwnode_for_each_child_node(atr_node, child) { + ret = fwnode_property_read_u32(child, "reg", ®); + if (ret) + continue; + if (chan_id == reg) + break; + } + + device_set_node(&chan->adap.dev, child); + fwnode_handle_put(atr_node); + } + + atr->adapter[chan_id] = &chan->adap; + + ret = i2c_add_adapter(&chan->adap); + if (ret) { + dev_err(dev, "failed to add atr-adapter %u (error=%d)\n", + chan_id, ret); + goto err_fwnode_put; + } + + snprintf(symlink_name, sizeof(symlink_name), "channel-%u", + chan->chan_id); + + ret = sysfs_create_link(&chan->adap.dev.kobj, &dev->kobj, "atr_device"); + if (ret) + dev_warn(dev, "can't create symlink to atr device\n"); + ret = sysfs_create_link(&dev->kobj, &chan->adap.dev.kobj, symlink_name); + if (ret) + dev_warn(dev, "can't create symlink for channel %u\n", chan_id); + + dev_dbg(dev, "Added ATR child bus %d\n", i2c_adapter_id(&chan->adap)); + + return 0; + +err_fwnode_put: + fwnode_handle_put(dev_fwnode(&chan->adap.dev)); + mutex_destroy(&chan->orig_addrs_lock); + kfree(chan); + return ret; +} +EXPORT_SYMBOL_NS_GPL(i2c_atr_add_adapter, I2C_ATR); + +void i2c_atr_del_adapter(struct i2c_atr *atr, u32 chan_id) +{ + char symlink_name[ATR_MAX_SYMLINK_LEN]; + struct i2c_adapter *adap; + struct i2c_atr_chan *chan; + struct fwnode_handle *fwnode; + struct device *dev = atr->dev; + + adap = atr->adapter[chan_id]; + if (!adap) + return; + + chan = adap->algo_data; + fwnode = dev_fwnode(&adap->dev); + + dev_dbg(dev, "Removing ATR child bus %d\n", i2c_adapter_id(adap)); + + snprintf(symlink_name, sizeof(symlink_name), "channel-%u", + chan->chan_id); + sysfs_remove_link(&dev->kobj, symlink_name); + sysfs_remove_link(&chan->adap.dev.kobj, "atr_device"); + + i2c_del_adapter(adap); + + atr->adapter[chan_id] = NULL; + + fwnode_handle_put(fwnode); + mutex_destroy(&chan->orig_addrs_lock); + kfree(chan->orig_addrs); + kfree(chan); +} +EXPORT_SYMBOL_NS_GPL(i2c_atr_del_adapter, I2C_ATR); + +void i2c_atr_set_driver_data(struct i2c_atr *atr, void *data) +{ + atr->priv = data; +} +EXPORT_SYMBOL_NS_GPL(i2c_atr_set_driver_data, I2C_ATR); + +void *i2c_atr_get_driver_data(struct i2c_atr *atr) +{ + return atr->priv; +} +EXPORT_SYMBOL_NS_GPL(i2c_atr_get_driver_data, I2C_ATR); + +MODULE_AUTHOR("Luca Ceresoli <luca.ceresoli@bootlin.com>"); +MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>"); +MODULE_DESCRIPTION("I2C Address Translator"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/i2c-boardinfo.c b/drivers/i2c/i2c-boardinfo.c new file mode 100644 index 000000000..4df8ad092 --- /dev/null +++ b/drivers/i2c/i2c-boardinfo.c @@ -0,0 +1,93 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * i2c-boardinfo.c - collect pre-declarations of I2C devices + */ + +#include <linux/export.h> +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/property.h> +#include <linux/rwsem.h> +#include <linux/slab.h> + +#include "i2c-core.h" + + +/* These symbols are exported ONLY FOR the i2c core. + * No other users will be supported. + */ +DECLARE_RWSEM(__i2c_board_lock); +EXPORT_SYMBOL_GPL(__i2c_board_lock); + +LIST_HEAD(__i2c_board_list); +EXPORT_SYMBOL_GPL(__i2c_board_list); + +int __i2c_first_dynamic_bus_num; +EXPORT_SYMBOL_GPL(__i2c_first_dynamic_bus_num); + + +/** + * i2c_register_board_info - statically declare I2C devices + * @busnum: identifies the bus to which these devices belong + * @info: vector of i2c device descriptors + * @len: how many descriptors in the vector; may be zero to reserve + * the specified bus number. + * + * Systems using the Linux I2C driver stack can declare tables of board info + * while they initialize. This should be done in board-specific init code + * near arch_initcall() time, or equivalent, before any I2C adapter driver is + * registered. For example, mainboard init code could define several devices, + * as could the init code for each daughtercard in a board stack. + * + * The I2C devices will be created later, after the adapter for the relevant + * bus has been registered. After that moment, standard driver model tools + * are used to bind "new style" I2C drivers to the devices. The bus number + * for any device declared using this routine is not available for dynamic + * allocation. + * + * The board info passed can safely be __initdata, but be careful of embedded + * pointers (for platform_data, functions, etc) since that won't be copied. + */ +int i2c_register_board_info(int busnum, struct i2c_board_info const *info, unsigned len) +{ + int status; + + down_write(&__i2c_board_lock); + + /* dynamic bus numbers will be assigned after the last static one */ + if (busnum >= __i2c_first_dynamic_bus_num) + __i2c_first_dynamic_bus_num = busnum + 1; + + for (status = 0; len; len--, info++) { + struct i2c_devinfo *devinfo; + + devinfo = kzalloc(sizeof(*devinfo), GFP_KERNEL); + if (!devinfo) { + pr_debug("i2c-core: can't register boardinfo!\n"); + status = -ENOMEM; + break; + } + + devinfo->busnum = busnum; + devinfo->board_info = *info; + + if (info->resources) { + devinfo->board_info.resources = + kmemdup(info->resources, + info->num_resources * + sizeof(*info->resources), + GFP_KERNEL); + if (!devinfo->board_info.resources) { + status = -ENOMEM; + kfree(devinfo); + break; + } + } + + list_add_tail(&devinfo->list, &__i2c_board_list); + } + + up_write(&__i2c_board_lock); + + return status; +} diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c new file mode 100644 index 000000000..d6037a328 --- /dev/null +++ b/drivers/i2c/i2c-core-acpi.c @@ -0,0 +1,813 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Linux I2C core ACPI support code + * + * Copyright (C) 2014 Intel Corp, Author: Lan Tianyu <tianyu.lan@intel.com> + */ + +#include <linux/acpi.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/slab.h> + +#include "i2c-core.h" + +struct i2c_acpi_handler_data { + struct acpi_connection_info info; + struct i2c_adapter *adapter; +}; + +struct gsb_buffer { + u8 status; + u8 len; + union { + u16 wdata; + u8 bdata; + DECLARE_FLEX_ARRAY(u8, data); + }; +} __packed; + +struct i2c_acpi_lookup { + struct i2c_board_info *info; + acpi_handle adapter_handle; + acpi_handle device_handle; + acpi_handle search_handle; + int n; + int index; + u32 speed; + u32 min_speed; + u32 force_speed; +}; + +/** + * i2c_acpi_get_i2c_resource - Gets I2cSerialBus resource if type matches + * @ares: ACPI resource + * @i2c: Pointer to I2cSerialBus resource will be returned here + * + * Checks if the given ACPI resource is of type I2cSerialBus. + * In this case, returns a pointer to it to the caller. + * + * Returns true if resource type is of I2cSerialBus, otherwise false. + */ +bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares, + struct acpi_resource_i2c_serialbus **i2c) +{ + struct acpi_resource_i2c_serialbus *sb; + + if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) + return false; + + sb = &ares->data.i2c_serial_bus; + if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) + return false; + + *i2c = sb; + return true; +} +EXPORT_SYMBOL_GPL(i2c_acpi_get_i2c_resource); + +static int i2c_acpi_resource_count(struct acpi_resource *ares, void *data) +{ + struct acpi_resource_i2c_serialbus *sb; + int *count = data; + + if (i2c_acpi_get_i2c_resource(ares, &sb)) + *count = *count + 1; + + return 1; +} + +/** + * i2c_acpi_client_count - Count the number of I2cSerialBus resources + * @adev: ACPI device + * + * Returns the number of I2cSerialBus resources in the ACPI-device's + * resource-list; or a negative error code. + */ +int i2c_acpi_client_count(struct acpi_device *adev) +{ + int ret, count = 0; + LIST_HEAD(r); + + ret = acpi_dev_get_resources(adev, &r, i2c_acpi_resource_count, &count); + if (ret < 0) + return ret; + + acpi_dev_free_resource_list(&r); + return count; +} +EXPORT_SYMBOL_GPL(i2c_acpi_client_count); + +static int i2c_acpi_fill_info(struct acpi_resource *ares, void *data) +{ + struct i2c_acpi_lookup *lookup = data; + struct i2c_board_info *info = lookup->info; + struct acpi_resource_i2c_serialbus *sb; + acpi_status status; + + if (info->addr || !i2c_acpi_get_i2c_resource(ares, &sb)) + return 1; + + if (lookup->index != -1 && lookup->n++ != lookup->index) + return 1; + + status = acpi_get_handle(lookup->device_handle, + sb->resource_source.string_ptr, + &lookup->adapter_handle); + if (ACPI_FAILURE(status)) + return 1; + + info->addr = sb->slave_address; + lookup->speed = sb->connection_speed; + if (sb->access_mode == ACPI_I2C_10BIT_MODE) + info->flags |= I2C_CLIENT_TEN; + + return 1; +} + +static const struct acpi_device_id i2c_acpi_ignored_device_ids[] = { + /* + * ACPI video acpi_devices, which are handled by the acpi-video driver + * sometimes contain a SERIAL_TYPE_I2C ACPI resource, ignore these. + */ + { ACPI_VIDEO_HID, 0 }, + {} +}; + +struct i2c_acpi_irq_context { + int irq; + bool wake_capable; +}; + +static int i2c_acpi_do_lookup(struct acpi_device *adev, + struct i2c_acpi_lookup *lookup) +{ + struct i2c_board_info *info = lookup->info; + struct list_head resource_list; + int ret; + + if (acpi_bus_get_status(adev)) + return -EINVAL; + + if (!acpi_dev_ready_for_enumeration(adev)) + return -ENODEV; + + if (acpi_match_device_ids(adev, i2c_acpi_ignored_device_ids) == 0) + return -ENODEV; + + memset(info, 0, sizeof(*info)); + lookup->device_handle = acpi_device_handle(adev); + + /* Look up for I2cSerialBus resource */ + INIT_LIST_HEAD(&resource_list); + ret = acpi_dev_get_resources(adev, &resource_list, + i2c_acpi_fill_info, lookup); + acpi_dev_free_resource_list(&resource_list); + + if (ret < 0 || !info->addr) + return -EINVAL; + + return 0; +} + +static int i2c_acpi_add_irq_resource(struct acpi_resource *ares, void *data) +{ + struct i2c_acpi_irq_context *irq_ctx = data; + struct resource r; + + if (irq_ctx->irq > 0) + return 1; + + if (!acpi_dev_resource_interrupt(ares, 0, &r)) + return 1; + + irq_ctx->irq = i2c_dev_irq_from_resources(&r, 1); + irq_ctx->wake_capable = r.flags & IORESOURCE_IRQ_WAKECAPABLE; + + return 1; /* No need to add resource to the list */ +} + +/** + * i2c_acpi_get_irq - get device IRQ number from ACPI + * @client: Pointer to the I2C client device + * @wake_capable: Set to true if the IRQ is wake capable + * + * Find the IRQ number used by a specific client device. + * + * Return: The IRQ number or an error code. + */ +int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable) +{ + struct acpi_device *adev = ACPI_COMPANION(&client->dev); + struct list_head resource_list; + struct i2c_acpi_irq_context irq_ctx = { + .irq = -ENOENT, + }; + int ret; + + INIT_LIST_HEAD(&resource_list); + + ret = acpi_dev_get_resources(adev, &resource_list, + i2c_acpi_add_irq_resource, &irq_ctx); + if (ret < 0) + return ret; + + acpi_dev_free_resource_list(&resource_list); + + if (irq_ctx.irq == -ENOENT) + irq_ctx.irq = acpi_dev_gpio_irq_wake_get(adev, 0, &irq_ctx.wake_capable); + + if (irq_ctx.irq < 0) + return irq_ctx.irq; + + if (wake_capable) + *wake_capable = irq_ctx.wake_capable; + + return irq_ctx.irq; +} + +static int i2c_acpi_get_info(struct acpi_device *adev, + struct i2c_board_info *info, + struct i2c_adapter *adapter, + acpi_handle *adapter_handle) +{ + struct i2c_acpi_lookup lookup; + int ret; + + memset(&lookup, 0, sizeof(lookup)); + lookup.info = info; + lookup.index = -1; + + if (acpi_device_enumerated(adev)) + return -EINVAL; + + ret = i2c_acpi_do_lookup(adev, &lookup); + if (ret) + return ret; + + if (adapter) { + /* The adapter must match the one in I2cSerialBus() connector */ + if (ACPI_HANDLE(&adapter->dev) != lookup.adapter_handle) + return -ENODEV; + } else { + struct acpi_device *adapter_adev; + + /* The adapter must be present */ + adapter_adev = acpi_fetch_acpi_dev(lookup.adapter_handle); + if (!adapter_adev) + return -ENODEV; + if (acpi_bus_get_status(adapter_adev) || + !adapter_adev->status.present) + return -ENODEV; + } + + info->fwnode = acpi_fwnode_handle(adev); + if (adapter_handle) + *adapter_handle = lookup.adapter_handle; + + acpi_set_modalias(adev, dev_name(&adev->dev), info->type, + sizeof(info->type)); + + return 0; +} + +static void i2c_acpi_register_device(struct i2c_adapter *adapter, + struct acpi_device *adev, + struct i2c_board_info *info) +{ + /* + * Skip registration on boards where the ACPI tables are + * known to contain bogus I2C devices. + */ + if (acpi_quirk_skip_i2c_client_enumeration(adev)) + return; + + adev->power.flags.ignore_parent = true; + acpi_device_set_enumerated(adev); + + if (IS_ERR(i2c_new_client_device(adapter, info))) + adev->power.flags.ignore_parent = false; +} + +static acpi_status i2c_acpi_add_device(acpi_handle handle, u32 level, + void *data, void **return_value) +{ + struct i2c_adapter *adapter = data; + struct acpi_device *adev = acpi_fetch_acpi_dev(handle); + struct i2c_board_info info; + + if (!adev || i2c_acpi_get_info(adev, &info, adapter, NULL)) + return AE_OK; + + i2c_acpi_register_device(adapter, adev, &info); + + return AE_OK; +} + +#define I2C_ACPI_MAX_SCAN_DEPTH 32 + +/** + * i2c_acpi_register_devices - enumerate I2C slave devices behind adapter + * @adap: pointer to adapter + * + * Enumerate all I2C slave devices behind this adapter by walking the ACPI + * namespace. When a device is found it will be added to the Linux device + * model and bound to the corresponding ACPI handle. + */ +void i2c_acpi_register_devices(struct i2c_adapter *adap) +{ + struct acpi_device *adev; + acpi_status status; + + if (!has_acpi_companion(&adap->dev)) + return; + + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, + I2C_ACPI_MAX_SCAN_DEPTH, + i2c_acpi_add_device, NULL, + adap, NULL); + if (ACPI_FAILURE(status)) + dev_warn(&adap->dev, "failed to enumerate I2C slaves\n"); + + if (!adap->dev.parent) + return; + + adev = ACPI_COMPANION(adap->dev.parent); + if (!adev) + return; + + acpi_dev_clear_dependencies(adev); +} + +static const struct acpi_device_id i2c_acpi_force_400khz_device_ids[] = { + /* + * These Silead touchscreen controllers only work at 400KHz, for + * some reason they do not work at 100KHz. On some devices the ACPI + * tables list another device at their bus as only being capable + * of 100KHz, testing has shown that these other devices work fine + * at 400KHz (as can be expected of any recent i2c hw) so we force + * the speed of the bus to 400 KHz if a Silead device is present. + */ + { "MSSL1680", 0 }, + {} +}; + +static acpi_status i2c_acpi_lookup_speed(acpi_handle handle, u32 level, + void *data, void **return_value) +{ + struct i2c_acpi_lookup *lookup = data; + struct acpi_device *adev = acpi_fetch_acpi_dev(handle); + + if (!adev || i2c_acpi_do_lookup(adev, lookup)) + return AE_OK; + + if (lookup->search_handle != lookup->adapter_handle) + return AE_OK; + + if (lookup->speed <= lookup->min_speed) + lookup->min_speed = lookup->speed; + + if (acpi_match_device_ids(adev, i2c_acpi_force_400khz_device_ids) == 0) + lookup->force_speed = I2C_MAX_FAST_MODE_FREQ; + + return AE_OK; +} + +/** + * i2c_acpi_find_bus_speed - find I2C bus speed from ACPI + * @dev: The device owning the bus + * + * Find the I2C bus speed by walking the ACPI namespace for all I2C slaves + * devices connected to this bus and use the speed of slowest device. + * + * Returns the speed in Hz or zero + */ +u32 i2c_acpi_find_bus_speed(struct device *dev) +{ + struct i2c_acpi_lookup lookup; + struct i2c_board_info dummy; + acpi_status status; + + if (!has_acpi_companion(dev)) + return 0; + + memset(&lookup, 0, sizeof(lookup)); + lookup.search_handle = ACPI_HANDLE(dev); + lookup.min_speed = UINT_MAX; + lookup.info = &dummy; + lookup.index = -1; + + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, + I2C_ACPI_MAX_SCAN_DEPTH, + i2c_acpi_lookup_speed, NULL, + &lookup, NULL); + + if (ACPI_FAILURE(status)) { + dev_warn(dev, "unable to find I2C bus speed from ACPI\n"); + return 0; + } + + if (lookup.force_speed) { + if (lookup.force_speed != lookup.min_speed) + dev_warn(dev, FW_BUG "DSDT uses known not-working I2C bus speed %d, forcing it to %d\n", + lookup.min_speed, lookup.force_speed); + return lookup.force_speed; + } else if (lookup.min_speed != UINT_MAX) { + return lookup.min_speed; + } else { + return 0; + } +} +EXPORT_SYMBOL_GPL(i2c_acpi_find_bus_speed); + +struct i2c_adapter *i2c_acpi_find_adapter_by_handle(acpi_handle handle) +{ + struct i2c_adapter *adapter; + struct device *dev; + + dev = bus_find_device(&i2c_bus_type, NULL, handle, device_match_acpi_handle); + if (!dev) + return NULL; + + adapter = i2c_verify_adapter(dev); + if (!adapter) + put_device(dev); + + return adapter; +} +EXPORT_SYMBOL_GPL(i2c_acpi_find_adapter_by_handle); + +static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev) +{ + return i2c_find_device_by_fwnode(acpi_fwnode_handle(adev)); +} + +static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value, + void *arg) +{ + struct acpi_device *adev = arg; + struct i2c_board_info info; + acpi_handle adapter_handle; + struct i2c_adapter *adapter; + struct i2c_client *client; + + switch (value) { + case ACPI_RECONFIG_DEVICE_ADD: + if (i2c_acpi_get_info(adev, &info, NULL, &adapter_handle)) + break; + + adapter = i2c_acpi_find_adapter_by_handle(adapter_handle); + if (!adapter) + break; + + i2c_acpi_register_device(adapter, adev, &info); + put_device(&adapter->dev); + break; + case ACPI_RECONFIG_DEVICE_REMOVE: + if (!acpi_device_enumerated(adev)) + break; + + client = i2c_acpi_find_client_by_adev(adev); + if (!client) + break; + + i2c_unregister_device(client); + put_device(&client->dev); + break; + } + + return NOTIFY_OK; +} + +struct notifier_block i2c_acpi_notifier = { + .notifier_call = i2c_acpi_notify, +}; + +/** + * i2c_acpi_new_device_by_fwnode - Create i2c-client for the Nth I2cSerialBus resource + * @fwnode: fwnode with the ACPI resources to get the client from + * @index: Index of ACPI resource to get + * @info: describes the I2C device; note this is modified (addr gets set) + * Context: can sleep + * + * By default the i2c subsys creates an i2c-client for the first I2cSerialBus + * resource of an acpi_device, but some acpi_devices have multiple I2cSerialBus + * resources, in that case this function can be used to create an i2c-client + * for other I2cSerialBus resources in the Current Resource Settings table. + * + * Also see i2c_new_client_device, which this function calls to create the + * i2c-client. + * + * Returns a pointer to the new i2c-client, or error pointer in case of failure. + * Specifically, -EPROBE_DEFER is returned if the adapter is not found. + */ +struct i2c_client *i2c_acpi_new_device_by_fwnode(struct fwnode_handle *fwnode, + int index, + struct i2c_board_info *info) +{ + struct i2c_acpi_lookup lookup; + struct i2c_adapter *adapter; + struct acpi_device *adev; + LIST_HEAD(resource_list); + int ret; + + adev = to_acpi_device_node(fwnode); + if (!adev) + return ERR_PTR(-ENODEV); + + memset(&lookup, 0, sizeof(lookup)); + lookup.info = info; + lookup.device_handle = acpi_device_handle(adev); + lookup.index = index; + + ret = acpi_dev_get_resources(adev, &resource_list, + i2c_acpi_fill_info, &lookup); + if (ret < 0) + return ERR_PTR(ret); + + acpi_dev_free_resource_list(&resource_list); + + if (!info->addr) + return ERR_PTR(-EADDRNOTAVAIL); + + adapter = i2c_acpi_find_adapter_by_handle(lookup.adapter_handle); + if (!adapter) + return ERR_PTR(-EPROBE_DEFER); + + return i2c_new_client_device(adapter, info); +} +EXPORT_SYMBOL_GPL(i2c_acpi_new_device_by_fwnode); + +bool i2c_acpi_waive_d0_probe(struct device *dev) +{ + struct i2c_driver *driver = to_i2c_driver(dev->driver); + struct acpi_device *adev = ACPI_COMPANION(dev); + + return driver->flags & I2C_DRV_ACPI_WAIVE_D0_PROBE && + adev && adev->power.state_for_enumeration >= adev->power.state; +} +EXPORT_SYMBOL_GPL(i2c_acpi_waive_d0_probe); + +#ifdef CONFIG_ACPI_I2C_OPREGION +static int acpi_gsb_i2c_read_bytes(struct i2c_client *client, + u8 cmd, u8 *data, u8 data_len) +{ + + struct i2c_msg msgs[2]; + int ret; + u8 *buffer; + + buffer = kzalloc(data_len, GFP_KERNEL); + if (!buffer) + return AE_NO_MEMORY; + + msgs[0].addr = client->addr; + msgs[0].flags = client->flags; + msgs[0].len = 1; + msgs[0].buf = &cmd; + + msgs[1].addr = client->addr; + msgs[1].flags = client->flags | I2C_M_RD; + msgs[1].len = data_len; + msgs[1].buf = buffer; + + ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); + if (ret < 0) { + /* Getting a NACK is unfortunately normal with some DSTDs */ + if (ret == -EREMOTEIO) + dev_dbg(&client->adapter->dev, "i2c read %d bytes from client@%#x starting at reg %#x failed, error: %d\n", + data_len, client->addr, cmd, ret); + else + dev_err(&client->adapter->dev, "i2c read %d bytes from client@%#x starting at reg %#x failed, error: %d\n", + data_len, client->addr, cmd, ret); + /* 2 transfers must have completed successfully */ + } else if (ret == 2) { + memcpy(data, buffer, data_len); + ret = 0; + } else { + ret = -EIO; + } + + kfree(buffer); + return ret; +} + +static int acpi_gsb_i2c_write_bytes(struct i2c_client *client, + u8 cmd, u8 *data, u8 data_len) +{ + + struct i2c_msg msgs[1]; + u8 *buffer; + int ret = AE_OK; + + buffer = kzalloc(data_len + 1, GFP_KERNEL); + if (!buffer) + return AE_NO_MEMORY; + + buffer[0] = cmd; + memcpy(buffer + 1, data, data_len); + + msgs[0].addr = client->addr; + msgs[0].flags = client->flags; + msgs[0].len = data_len + 1; + msgs[0].buf = buffer; + + ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); + + kfree(buffer); + + if (ret < 0) { + dev_err(&client->adapter->dev, "i2c write failed: %d\n", ret); + return ret; + } + + /* 1 transfer must have completed successfully */ + return (ret == 1) ? 0 : -EIO; +} + +static acpi_status +i2c_acpi_space_handler(u32 function, acpi_physical_address command, + u32 bits, u64 *value64, + void *handler_context, void *region_context) +{ + struct gsb_buffer *gsb = (struct gsb_buffer *)value64; + struct i2c_acpi_handler_data *data = handler_context; + struct acpi_connection_info *info = &data->info; + struct acpi_resource_i2c_serialbus *sb; + struct i2c_adapter *adapter = data->adapter; + struct i2c_client *client; + struct acpi_resource *ares; + u32 accessor_type = function >> 16; + u8 action = function & ACPI_IO_MASK; + acpi_status ret; + int status; + + ret = acpi_buffer_to_resource(info->connection, info->length, &ares); + if (ACPI_FAILURE(ret)) + return ret; + + client = kzalloc(sizeof(*client), GFP_KERNEL); + if (!client) { + ret = AE_NO_MEMORY; + goto err; + } + + if (!value64 || !i2c_acpi_get_i2c_resource(ares, &sb)) { + ret = AE_BAD_PARAMETER; + goto err; + } + + client->adapter = adapter; + client->addr = sb->slave_address; + + if (sb->access_mode == ACPI_I2C_10BIT_MODE) + client->flags |= I2C_CLIENT_TEN; + + switch (accessor_type) { + case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV: + if (action == ACPI_READ) { + status = i2c_smbus_read_byte(client); + if (status >= 0) { + gsb->bdata = status; + status = 0; + } + } else { + status = i2c_smbus_write_byte(client, gsb->bdata); + } + break; + + case ACPI_GSB_ACCESS_ATTRIB_BYTE: + if (action == ACPI_READ) { + status = i2c_smbus_read_byte_data(client, command); + if (status >= 0) { + gsb->bdata = status; + status = 0; + } + } else { + status = i2c_smbus_write_byte_data(client, command, + gsb->bdata); + } + break; + + case ACPI_GSB_ACCESS_ATTRIB_WORD: + if (action == ACPI_READ) { + status = i2c_smbus_read_word_data(client, command); + if (status >= 0) { + gsb->wdata = status; + status = 0; + } + } else { + status = i2c_smbus_write_word_data(client, command, + gsb->wdata); + } + break; + + case ACPI_GSB_ACCESS_ATTRIB_BLOCK: + if (action == ACPI_READ) { + status = i2c_smbus_read_block_data(client, command, + gsb->data); + if (status >= 0) { + gsb->len = status; + status = 0; + } + } else { + status = i2c_smbus_write_block_data(client, command, + gsb->len, gsb->data); + } + break; + + case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE: + if (action == ACPI_READ) { + status = acpi_gsb_i2c_read_bytes(client, command, + gsb->data, info->access_length); + } else { + status = acpi_gsb_i2c_write_bytes(client, command, + gsb->data, info->access_length); + } + break; + + default: + dev_warn(&adapter->dev, "protocol 0x%02x not supported for client 0x%02x\n", + accessor_type, client->addr); + ret = AE_BAD_PARAMETER; + goto err; + } + + gsb->status = status; + + err: + kfree(client); + ACPI_FREE(ares); + return ret; +} + + +int i2c_acpi_install_space_handler(struct i2c_adapter *adapter) +{ + acpi_handle handle; + struct i2c_acpi_handler_data *data; + acpi_status status; + + if (!adapter->dev.parent) + return -ENODEV; + + handle = ACPI_HANDLE(adapter->dev.parent); + + if (!handle) + return -ENODEV; + + data = kzalloc(sizeof(struct i2c_acpi_handler_data), + GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->adapter = adapter; + status = acpi_bus_attach_private_data(handle, (void *)data); + if (ACPI_FAILURE(status)) { + kfree(data); + return -ENOMEM; + } + + status = acpi_install_address_space_handler(handle, + ACPI_ADR_SPACE_GSBUS, + &i2c_acpi_space_handler, + NULL, + data); + if (ACPI_FAILURE(status)) { + dev_err(&adapter->dev, "Error installing i2c space handler\n"); + acpi_bus_detach_private_data(handle); + kfree(data); + return -ENOMEM; + } + + return 0; +} + +void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) +{ + acpi_handle handle; + struct i2c_acpi_handler_data *data; + acpi_status status; + + if (!adapter->dev.parent) + return; + + handle = ACPI_HANDLE(adapter->dev.parent); + + if (!handle) + return; + + acpi_remove_address_space_handler(handle, + ACPI_ADR_SPACE_GSBUS, + &i2c_acpi_space_handler); + + status = acpi_bus_get_private_data(handle, (void **)&data); + if (ACPI_SUCCESS(status)) + kfree(data); + + acpi_bus_detach_private_data(handle); +} +#endif /* CONFIG_ACPI_I2C_OPREGION */ diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c new file mode 100644 index 000000000..7f30bccee --- /dev/null +++ b/drivers/i2c/i2c-core-base.c @@ -0,0 +1,2656 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Linux I2C core + * + * Copyright (C) 1995-99 Simon G. Vogl + * With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> + * Mux support by Rodolfo Giometti <giometti@enneenne.com> and + * Michael Lawnick <michael.lawnick.ext@nsn.com> + * + * Copyright (C) 2013-2017 Wolfram Sang <wsa@kernel.org> + */ + +#define pr_fmt(fmt) "i2c-core: " fmt + +#include <dt-bindings/i2c/i2c.h> +#include <linux/acpi.h> +#include <linux/clk/clk-conf.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/i2c-smbus.h> +#include <linux/idr.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/irqflags.h> +#include <linux/jump_label.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of_device.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/pinctrl/consumer.h> +#include <linux/pinctrl/devinfo.h> +#include <linux/pm_domain.h> +#include <linux/pm_runtime.h> +#include <linux/pm_wakeirq.h> +#include <linux/property.h> +#include <linux/rwsem.h> +#include <linux/slab.h> + +#include "i2c-core.h" + +#define CREATE_TRACE_POINTS +#include <trace/events/i2c.h> + +#define I2C_ADDR_OFFSET_TEN_BIT 0xa000 +#define I2C_ADDR_OFFSET_SLAVE 0x1000 + +#define I2C_ADDR_7BITS_MAX 0x77 +#define I2C_ADDR_7BITS_COUNT (I2C_ADDR_7BITS_MAX + 1) + +#define I2C_ADDR_DEVICE_ID 0x7c + +/* + * core_lock protects i2c_adapter_idr, and guarantees that device detection, + * deletion of detected devices are serialized + */ +static DEFINE_MUTEX(core_lock); +static DEFINE_IDR(i2c_adapter_idr); + +static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); + +static DEFINE_STATIC_KEY_FALSE(i2c_trace_msg_key); +static bool is_registered; + +int i2c_transfer_trace_reg(void) +{ + static_branch_inc(&i2c_trace_msg_key); + return 0; +} + +void i2c_transfer_trace_unreg(void) +{ + static_branch_dec(&i2c_trace_msg_key); +} + +const char *i2c_freq_mode_string(u32 bus_freq_hz) +{ + switch (bus_freq_hz) { + case I2C_MAX_STANDARD_MODE_FREQ: + return "Standard Mode (100 kHz)"; + case I2C_MAX_FAST_MODE_FREQ: + return "Fast Mode (400 kHz)"; + case I2C_MAX_FAST_MODE_PLUS_FREQ: + return "Fast Mode Plus (1.0 MHz)"; + case I2C_MAX_TURBO_MODE_FREQ: + return "Turbo Mode (1.4 MHz)"; + case I2C_MAX_HIGH_SPEED_MODE_FREQ: + return "High Speed Mode (3.4 MHz)"; + case I2C_MAX_ULTRA_FAST_MODE_FREQ: + return "Ultra Fast Mode (5.0 MHz)"; + default: + return "Unknown Mode"; + } +} +EXPORT_SYMBOL_GPL(i2c_freq_mode_string); + +const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, + const struct i2c_client *client) +{ + if (!(id && client)) + return NULL; + + while (id->name[0]) { + if (strcmp(client->name, id->name) == 0) + return id; + id++; + } + return NULL; +} +EXPORT_SYMBOL_GPL(i2c_match_id); + +const void *i2c_get_match_data(const struct i2c_client *client) +{ + struct i2c_driver *driver = to_i2c_driver(client->dev.driver); + const struct i2c_device_id *match; + const void *data; + + data = device_get_match_data(&client->dev); + if (!data) { + match = i2c_match_id(driver->id_table, client); + if (!match) + return NULL; + + data = (const void *)match->driver_data; + } + + return data; +} +EXPORT_SYMBOL(i2c_get_match_data); + +static int i2c_device_match(struct device *dev, struct device_driver *drv) +{ + struct i2c_client *client = i2c_verify_client(dev); + struct i2c_driver *driver; + + + /* Attempt an OF style match */ + if (i2c_of_match_device(drv->of_match_table, client)) + return 1; + + /* Then ACPI style match */ + if (acpi_driver_match_device(dev, drv)) + return 1; + + driver = to_i2c_driver(drv); + + /* Finally an I2C match */ + if (i2c_match_id(driver->id_table, client)) + return 1; + + return 0; +} + +static int i2c_device_uevent(const struct device *dev, struct kobj_uevent_env *env) +{ + const struct i2c_client *client = to_i2c_client(dev); + int rc; + + rc = of_device_uevent_modalias(dev, env); + if (rc != -ENODEV) + return rc; + + rc = acpi_device_uevent_modalias(dev, env); + if (rc != -ENODEV) + return rc; + + return add_uevent_var(env, "MODALIAS=%s%s", I2C_MODULE_PREFIX, client->name); +} + +/* i2c bus recovery routines */ +static int get_scl_gpio_value(struct i2c_adapter *adap) +{ + return gpiod_get_value_cansleep(adap->bus_recovery_info->scl_gpiod); +} + +static void set_scl_gpio_value(struct i2c_adapter *adap, int val) +{ + gpiod_set_value_cansleep(adap->bus_recovery_info->scl_gpiod, val); +} + +static int get_sda_gpio_value(struct i2c_adapter *adap) +{ + return gpiod_get_value_cansleep(adap->bus_recovery_info->sda_gpiod); +} + +static void set_sda_gpio_value(struct i2c_adapter *adap, int val) +{ + gpiod_set_value_cansleep(adap->bus_recovery_info->sda_gpiod, val); +} + +static int i2c_generic_bus_free(struct i2c_adapter *adap) +{ + struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; + int ret = -EOPNOTSUPP; + + if (bri->get_bus_free) + ret = bri->get_bus_free(adap); + else if (bri->get_sda) + ret = bri->get_sda(adap); + + if (ret < 0) + return ret; + + return ret ? 0 : -EBUSY; +} + +/* + * We are generating clock pulses. ndelay() determines durating of clk pulses. + * We will generate clock with rate 100 KHz and so duration of both clock levels + * is: delay in ns = (10^6 / 100) / 2 + */ +#define RECOVERY_NDELAY 5000 +#define RECOVERY_CLK_CNT 9 + +int i2c_generic_scl_recovery(struct i2c_adapter *adap) +{ + struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; + int i = 0, scl = 1, ret = 0; + + if (bri->prepare_recovery) + bri->prepare_recovery(adap); + if (bri->pinctrl) + pinctrl_select_state(bri->pinctrl, bri->pins_gpio); + + /* + * If we can set SDA, we will always create a STOP to ensure additional + * pulses will do no harm. This is achieved by letting SDA follow SCL + * half a cycle later. Check the 'incomplete_write_byte' fault injector + * for details. Note that we must honour tsu:sto, 4us, but lets use 5us + * here for simplicity. + */ + bri->set_scl(adap, scl); + ndelay(RECOVERY_NDELAY); + if (bri->set_sda) + bri->set_sda(adap, scl); + ndelay(RECOVERY_NDELAY / 2); + + /* + * By this time SCL is high, as we need to give 9 falling-rising edges + */ + while (i++ < RECOVERY_CLK_CNT * 2) { + if (scl) { + /* SCL shouldn't be low here */ + if (!bri->get_scl(adap)) { + dev_err(&adap->dev, + "SCL is stuck low, exit recovery\n"); + ret = -EBUSY; + break; + } + } + + scl = !scl; + bri->set_scl(adap, scl); + /* Creating STOP again, see above */ + if (scl) { + /* Honour minimum tsu:sto */ + ndelay(RECOVERY_NDELAY); + } else { + /* Honour minimum tf and thd:dat */ + ndelay(RECOVERY_NDELAY / 2); + } + if (bri->set_sda) + bri->set_sda(adap, scl); + ndelay(RECOVERY_NDELAY / 2); + + if (scl) { + ret = i2c_generic_bus_free(adap); + if (ret == 0) + break; + } + } + + /* If we can't check bus status, assume recovery worked */ + if (ret == -EOPNOTSUPP) + ret = 0; + + if (bri->unprepare_recovery) + bri->unprepare_recovery(adap); + if (bri->pinctrl) + pinctrl_select_state(bri->pinctrl, bri->pins_default); + + return ret; +} +EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery); + +int i2c_recover_bus(struct i2c_adapter *adap) +{ + if (!adap->bus_recovery_info) + return -EBUSY; + + dev_dbg(&adap->dev, "Trying i2c bus recovery\n"); + return adap->bus_recovery_info->recover_bus(adap); +} +EXPORT_SYMBOL_GPL(i2c_recover_bus); + +static void i2c_gpio_init_pinctrl_recovery(struct i2c_adapter *adap) +{ + struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; + struct device *dev = &adap->dev; + struct pinctrl *p = bri->pinctrl ?: dev_pinctrl(dev->parent); + + bri->pinctrl = p; + + /* + * we can't change states without pinctrl, so remove the states if + * populated + */ + if (!p) { + bri->pins_default = NULL; + bri->pins_gpio = NULL; + return; + } + + if (!bri->pins_default) { + bri->pins_default = pinctrl_lookup_state(p, + PINCTRL_STATE_DEFAULT); + if (IS_ERR(bri->pins_default)) { + dev_dbg(dev, PINCTRL_STATE_DEFAULT " state not found for GPIO recovery\n"); + bri->pins_default = NULL; + } + } + if (!bri->pins_gpio) { + bri->pins_gpio = pinctrl_lookup_state(p, "gpio"); + if (IS_ERR(bri->pins_gpio)) + bri->pins_gpio = pinctrl_lookup_state(p, "recovery"); + + if (IS_ERR(bri->pins_gpio)) { + dev_dbg(dev, "no gpio or recovery state found for GPIO recovery\n"); + bri->pins_gpio = NULL; + } + } + + /* for pinctrl state changes, we need all the information */ + if (bri->pins_default && bri->pins_gpio) { + dev_info(dev, "using pinctrl states for GPIO recovery"); + } else { + bri->pinctrl = NULL; + bri->pins_default = NULL; + bri->pins_gpio = NULL; + } +} + +static int i2c_gpio_init_generic_recovery(struct i2c_adapter *adap) +{ + struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; + struct device *dev = &adap->dev; + struct gpio_desc *gpiod; + int ret = 0; + + /* + * don't touch the recovery information if the driver is not using + * generic SCL recovery + */ + if (bri->recover_bus && bri->recover_bus != i2c_generic_scl_recovery) + return 0; + + /* + * pins might be taken as GPIO, so we should inform pinctrl about + * this and move the state to GPIO + */ + if (bri->pinctrl) + pinctrl_select_state(bri->pinctrl, bri->pins_gpio); + + /* + * if there is incomplete or no recovery information, see if generic + * GPIO recovery is available + */ + if (!bri->scl_gpiod) { + gpiod = devm_gpiod_get(dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN); + if (PTR_ERR(gpiod) == -EPROBE_DEFER) { + ret = -EPROBE_DEFER; + goto cleanup_pinctrl_state; + } + if (!IS_ERR(gpiod)) { + bri->scl_gpiod = gpiod; + bri->recover_bus = i2c_generic_scl_recovery; + dev_info(dev, "using generic GPIOs for recovery\n"); + } + } + + /* SDA GPIOD line is optional, so we care about DEFER only */ + if (!bri->sda_gpiod) { + /* + * We have SCL. Pull SCL low and wait a bit so that SDA glitches + * have no effect. + */ + gpiod_direction_output(bri->scl_gpiod, 0); + udelay(10); + gpiod = devm_gpiod_get(dev, "sda", GPIOD_IN); + + /* Wait a bit in case of a SDA glitch, and then release SCL. */ + udelay(10); + gpiod_direction_output(bri->scl_gpiod, 1); + + if (PTR_ERR(gpiod) == -EPROBE_DEFER) { + ret = -EPROBE_DEFER; + goto cleanup_pinctrl_state; + } + if (!IS_ERR(gpiod)) + bri->sda_gpiod = gpiod; + } + +cleanup_pinctrl_state: + /* change the state of the pins back to their default state */ + if (bri->pinctrl) + pinctrl_select_state(bri->pinctrl, bri->pins_default); + + return ret; +} + +static int i2c_gpio_init_recovery(struct i2c_adapter *adap) +{ + i2c_gpio_init_pinctrl_recovery(adap); + return i2c_gpio_init_generic_recovery(adap); +} + +static int i2c_init_recovery(struct i2c_adapter *adap) +{ + struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; + bool is_error_level = true; + char *err_str; + + if (!bri) + return 0; + + if (i2c_gpio_init_recovery(adap) == -EPROBE_DEFER) + return -EPROBE_DEFER; + + if (!bri->recover_bus) { + err_str = "no suitable method provided"; + is_error_level = false; + goto err; + } + + if (bri->scl_gpiod && bri->recover_bus == i2c_generic_scl_recovery) { + bri->get_scl = get_scl_gpio_value; + bri->set_scl = set_scl_gpio_value; + if (bri->sda_gpiod) { + bri->get_sda = get_sda_gpio_value; + /* FIXME: add proper flag instead of '0' once available */ + if (gpiod_get_direction(bri->sda_gpiod) == 0) + bri->set_sda = set_sda_gpio_value; + } + } else if (bri->recover_bus == i2c_generic_scl_recovery) { + /* Generic SCL recovery */ + if (!bri->set_scl || !bri->get_scl) { + err_str = "no {get|set}_scl() found"; + goto err; + } + if (!bri->set_sda && !bri->get_sda) { + err_str = "either get_sda() or set_sda() needed"; + goto err; + } + } + + return 0; + err: + if (is_error_level) + dev_err(&adap->dev, "Not using recovery: %s\n", err_str); + else + dev_dbg(&adap->dev, "Not using recovery: %s\n", err_str); + adap->bus_recovery_info = NULL; + + return -EINVAL; +} + +static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client) +{ + struct i2c_adapter *adap = client->adapter; + unsigned int irq; + + if (!adap->host_notify_domain) + return -ENXIO; + + if (client->flags & I2C_CLIENT_TEN) + return -EINVAL; + + irq = irq_create_mapping(adap->host_notify_domain, client->addr); + + return irq > 0 ? irq : -ENXIO; +} + +static int i2c_device_probe(struct device *dev) +{ + struct i2c_client *client = i2c_verify_client(dev); + struct i2c_driver *driver; + bool do_power_on; + int status; + + if (!client) + return 0; + + client->irq = client->init_irq; + + if (!client->irq) { + int irq = -ENOENT; + + if (client->flags & I2C_CLIENT_HOST_NOTIFY) { + dev_dbg(dev, "Using Host Notify IRQ\n"); + /* Keep adapter active when Host Notify is required */ + pm_runtime_get_sync(&client->adapter->dev); + irq = i2c_smbus_host_notify_to_irq(client); + } else if (dev->of_node) { + irq = of_irq_get_byname(dev->of_node, "irq"); + if (irq == -EINVAL || irq == -ENODATA) + irq = of_irq_get(dev->of_node, 0); + } else if (ACPI_COMPANION(dev)) { + bool wake_capable; + + irq = i2c_acpi_get_irq(client, &wake_capable); + if (irq > 0 && wake_capable) + client->flags |= I2C_CLIENT_WAKE; + } + if (irq == -EPROBE_DEFER) { + status = irq; + goto put_sync_adapter; + } + + if (irq < 0) + irq = 0; + + client->irq = irq; + } + + driver = to_i2c_driver(dev->driver); + + /* + * An I2C ID table is not mandatory, if and only if, a suitable OF + * or ACPI ID table is supplied for the probing device. + */ + if (!driver->id_table && + !acpi_driver_match_device(dev, dev->driver) && + !i2c_of_match_device(dev->driver->of_match_table, client)) { + status = -ENODEV; + goto put_sync_adapter; + } + + if (client->flags & I2C_CLIENT_WAKE) { + int wakeirq; + + wakeirq = of_irq_get_byname(dev->of_node, "wakeup"); + if (wakeirq == -EPROBE_DEFER) { + status = wakeirq; + goto put_sync_adapter; + } + + device_init_wakeup(&client->dev, true); + + if (wakeirq > 0 && wakeirq != client->irq) + status = dev_pm_set_dedicated_wake_irq(dev, wakeirq); + else if (client->irq > 0) + status = dev_pm_set_wake_irq(dev, client->irq); + else + status = 0; + + if (status) + dev_warn(&client->dev, "failed to set up wakeup irq\n"); + } + + dev_dbg(dev, "probe\n"); + + status = of_clk_set_defaults(dev->of_node, false); + if (status < 0) + goto err_clear_wakeup_irq; + + do_power_on = !i2c_acpi_waive_d0_probe(dev); + status = dev_pm_domain_attach(&client->dev, do_power_on); + if (status) + goto err_clear_wakeup_irq; + + client->devres_group_id = devres_open_group(&client->dev, NULL, + GFP_KERNEL); + if (!client->devres_group_id) { + status = -ENOMEM; + goto err_detach_pm_domain; + } + + if (driver->probe) + status = driver->probe(client); + else + status = -EINVAL; + + /* + * Note that we are not closing the devres group opened above so + * even resources that were attached to the device after probe is + * run are released when i2c_device_remove() is executed. This is + * needed as some drivers would allocate additional resources, + * for example when updating firmware. + */ + + if (status) + goto err_release_driver_resources; + + return 0; + +err_release_driver_resources: + devres_release_group(&client->dev, client->devres_group_id); +err_detach_pm_domain: + dev_pm_domain_detach(&client->dev, do_power_on); +err_clear_wakeup_irq: + dev_pm_clear_wake_irq(&client->dev); + device_init_wakeup(&client->dev, false); +put_sync_adapter: + if (client->flags & I2C_CLIENT_HOST_NOTIFY) + pm_runtime_put_sync(&client->adapter->dev); + + return status; +} + +static void i2c_device_remove(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct i2c_driver *driver; + + driver = to_i2c_driver(dev->driver); + if (driver->remove) { + dev_dbg(dev, "remove\n"); + + driver->remove(client); + } + + devres_release_group(&client->dev, client->devres_group_id); + + dev_pm_domain_detach(&client->dev, true); + + dev_pm_clear_wake_irq(&client->dev); + device_init_wakeup(&client->dev, false); + + client->irq = 0; + if (client->flags & I2C_CLIENT_HOST_NOTIFY) + pm_runtime_put(&client->adapter->dev); +} + +static void i2c_device_shutdown(struct device *dev) +{ + struct i2c_client *client = i2c_verify_client(dev); + struct i2c_driver *driver; + + if (!client || !dev->driver) + return; + driver = to_i2c_driver(dev->driver); + if (driver->shutdown) + driver->shutdown(client); + else if (client->irq > 0) + disable_irq(client->irq); +} + +static void i2c_client_dev_release(struct device *dev) +{ + kfree(to_i2c_client(dev)); +} + +static ssize_t +name_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? + to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); +} +static DEVICE_ATTR_RO(name); + +static ssize_t +modalias_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + int len; + + len = of_device_modalias(dev, buf, PAGE_SIZE); + if (len != -ENODEV) + return len; + + len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1); + if (len != -ENODEV) + return len; + + return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); +} +static DEVICE_ATTR_RO(modalias); + +static struct attribute *i2c_dev_attrs[] = { + &dev_attr_name.attr, + /* modalias helps coldplug: modprobe $(cat .../modalias) */ + &dev_attr_modalias.attr, + NULL +}; +ATTRIBUTE_GROUPS(i2c_dev); + +struct bus_type i2c_bus_type = { + .name = "i2c", + .match = i2c_device_match, + .probe = i2c_device_probe, + .remove = i2c_device_remove, + .shutdown = i2c_device_shutdown, +}; +EXPORT_SYMBOL_GPL(i2c_bus_type); + +struct device_type i2c_client_type = { + .groups = i2c_dev_groups, + .uevent = i2c_device_uevent, + .release = i2c_client_dev_release, +}; +EXPORT_SYMBOL_GPL(i2c_client_type); + + +/** + * i2c_verify_client - return parameter as i2c_client, or NULL + * @dev: device, probably from some driver model iterator + * + * When traversing the driver model tree, perhaps using driver model + * iterators like @device_for_each_child(), you can't assume very much + * about the nodes you find. Use this function to avoid oopses caused + * by wrongly treating some non-I2C device as an i2c_client. + */ +struct i2c_client *i2c_verify_client(struct device *dev) +{ + return (dev->type == &i2c_client_type) + ? to_i2c_client(dev) + : NULL; +} +EXPORT_SYMBOL(i2c_verify_client); + + +/* Return a unique address which takes the flags of the client into account */ +static unsigned short i2c_encode_flags_to_addr(struct i2c_client *client) +{ + unsigned short addr = client->addr; + + /* For some client flags, add an arbitrary offset to avoid collisions */ + if (client->flags & I2C_CLIENT_TEN) + addr |= I2C_ADDR_OFFSET_TEN_BIT; + + if (client->flags & I2C_CLIENT_SLAVE) + addr |= I2C_ADDR_OFFSET_SLAVE; + + return addr; +} + +/* This is a permissive address validity check, I2C address map constraints + * are purposely not enforced, except for the general call address. */ +static int i2c_check_addr_validity(unsigned int addr, unsigned short flags) +{ + if (flags & I2C_CLIENT_TEN) { + /* 10-bit address, all values are valid */ + if (addr > 0x3ff) + return -EINVAL; + } else { + /* 7-bit address, reject the general call address */ + if (addr == 0x00 || addr > 0x7f) + return -EINVAL; + } + return 0; +} + +/* And this is a strict address validity check, used when probing. If a + * device uses a reserved address, then it shouldn't be probed. 7-bit + * addressing is assumed, 10-bit address devices are rare and should be + * explicitly enumerated. */ +int i2c_check_7bit_addr_validity_strict(unsigned short addr) +{ + /* + * Reserved addresses per I2C specification: + * 0x00 General call address / START byte + * 0x01 CBUS address + * 0x02 Reserved for different bus format + * 0x03 Reserved for future purposes + * 0x04-0x07 Hs-mode master code + * 0x78-0x7b 10-bit slave addressing + * 0x7c-0x7f Reserved for future purposes + */ + if (addr < 0x08 || addr > 0x77) + return -EINVAL; + return 0; +} + +static int __i2c_check_addr_busy(struct device *dev, void *addrp) +{ + struct i2c_client *client = i2c_verify_client(dev); + int addr = *(int *)addrp; + + if (client && i2c_encode_flags_to_addr(client) == addr) + return -EBUSY; + return 0; +} + +/* walk up mux tree */ +static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) +{ + struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); + int result; + + result = device_for_each_child(&adapter->dev, &addr, + __i2c_check_addr_busy); + + if (!result && parent) + result = i2c_check_mux_parents(parent, addr); + + return result; +} + +/* recurse down mux tree */ +static int i2c_check_mux_children(struct device *dev, void *addrp) +{ + int result; + + if (dev->type == &i2c_adapter_type) + result = device_for_each_child(dev, addrp, + i2c_check_mux_children); + else + result = __i2c_check_addr_busy(dev, addrp); + + return result; +} + +static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) +{ + struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); + int result = 0; + + if (parent) + result = i2c_check_mux_parents(parent, addr); + + if (!result) + result = device_for_each_child(&adapter->dev, &addr, + i2c_check_mux_children); + + return result; +} + +/** + * i2c_adapter_lock_bus - Get exclusive access to an I2C bus segment + * @adapter: Target I2C bus segment + * @flags: I2C_LOCK_ROOT_ADAPTER locks the root i2c adapter, I2C_LOCK_SEGMENT + * locks only this branch in the adapter tree + */ +static void i2c_adapter_lock_bus(struct i2c_adapter *adapter, + unsigned int flags) +{ + rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter)); +} + +/** + * i2c_adapter_trylock_bus - Try to get exclusive access to an I2C bus segment + * @adapter: Target I2C bus segment + * @flags: I2C_LOCK_ROOT_ADAPTER trylocks the root i2c adapter, I2C_LOCK_SEGMENT + * trylocks only this branch in the adapter tree + */ +static int i2c_adapter_trylock_bus(struct i2c_adapter *adapter, + unsigned int flags) +{ + return rt_mutex_trylock(&adapter->bus_lock); +} + +/** + * i2c_adapter_unlock_bus - Release exclusive access to an I2C bus segment + * @adapter: Target I2C bus segment + * @flags: I2C_LOCK_ROOT_ADAPTER unlocks the root i2c adapter, I2C_LOCK_SEGMENT + * unlocks only this branch in the adapter tree + */ +static void i2c_adapter_unlock_bus(struct i2c_adapter *adapter, + unsigned int flags) +{ + rt_mutex_unlock(&adapter->bus_lock); +} + +static void i2c_dev_set_name(struct i2c_adapter *adap, + struct i2c_client *client, + struct i2c_board_info const *info) +{ + struct acpi_device *adev = ACPI_COMPANION(&client->dev); + + if (info && info->dev_name) { + dev_set_name(&client->dev, "i2c-%s", info->dev_name); + return; + } + + if (adev) { + dev_set_name(&client->dev, "i2c-%s", acpi_dev_name(adev)); + return; + } + + dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), + i2c_encode_flags_to_addr(client)); +} + +int i2c_dev_irq_from_resources(const struct resource *resources, + unsigned int num_resources) +{ + struct irq_data *irqd; + int i; + + for (i = 0; i < num_resources; i++) { + const struct resource *r = &resources[i]; + + if (resource_type(r) != IORESOURCE_IRQ) + continue; + + if (r->flags & IORESOURCE_BITS) { + irqd = irq_get_irq_data(r->start); + if (!irqd) + break; + + irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS); + } + + return r->start; + } + + return 0; +} + +/** + * i2c_new_client_device - instantiate an i2c device + * @adap: the adapter managing the device + * @info: describes one I2C device; bus_num is ignored + * Context: can sleep + * + * Create an i2c device. Binding is handled through driver model + * probe()/remove() methods. A driver may be bound to this device when we + * return from this function, or any later moment (e.g. maybe hotplugging will + * load the driver module). This call is not appropriate for use by mainboard + * initialization logic, which usually runs during an arch_initcall() long + * before any i2c_adapter could exist. + * + * This returns the new i2c client, which may be saved for later use with + * i2c_unregister_device(); or an ERR_PTR to describe the error. + */ +struct i2c_client * +i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *info) +{ + struct i2c_client *client; + bool need_put = false; + int status; + + client = kzalloc(sizeof *client, GFP_KERNEL); + if (!client) + return ERR_PTR(-ENOMEM); + + client->adapter = adap; + + client->dev.platform_data = info->platform_data; + client->flags = info->flags; + client->addr = info->addr; + + client->init_irq = info->irq; + if (!client->init_irq) + client->init_irq = i2c_dev_irq_from_resources(info->resources, + info->num_resources); + + strscpy(client->name, info->type, sizeof(client->name)); + + status = i2c_check_addr_validity(client->addr, client->flags); + if (status) { + dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", + client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); + goto out_err_silent; + } + + /* Check for address business */ + status = i2c_check_addr_busy(adap, i2c_encode_flags_to_addr(client)); + if (status) + goto out_err; + + client->dev.parent = &client->adapter->dev; + client->dev.bus = &i2c_bus_type; + client->dev.type = &i2c_client_type; + client->dev.of_node = of_node_get(info->of_node); + client->dev.fwnode = info->fwnode; + + device_enable_async_suspend(&client->dev); + + if (info->swnode) { + status = device_add_software_node(&client->dev, info->swnode); + if (status) { + dev_err(&adap->dev, + "Failed to add software node to client %s: %d\n", + client->name, status); + goto out_err_put_of_node; + } + } + + i2c_dev_set_name(adap, client, info); + status = device_register(&client->dev); + if (status) + goto out_remove_swnode; + + dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", + client->name, dev_name(&client->dev)); + + return client; + +out_remove_swnode: + device_remove_software_node(&client->dev); + need_put = true; +out_err_put_of_node: + of_node_put(info->of_node); +out_err: + dev_err(&adap->dev, + "Failed to register i2c client %s at 0x%02x (%d)\n", + client->name, client->addr, status); +out_err_silent: + if (need_put) + put_device(&client->dev); + else + kfree(client); + return ERR_PTR(status); +} +EXPORT_SYMBOL_GPL(i2c_new_client_device); + +/** + * i2c_unregister_device - reverse effect of i2c_new_*_device() + * @client: value returned from i2c_new_*_device() + * Context: can sleep + */ +void i2c_unregister_device(struct i2c_client *client) +{ + if (IS_ERR_OR_NULL(client)) + return; + + if (client->dev.of_node) { + of_node_clear_flag(client->dev.of_node, OF_POPULATED); + of_node_put(client->dev.of_node); + } + + if (ACPI_COMPANION(&client->dev)) + acpi_device_clear_enumerated(ACPI_COMPANION(&client->dev)); + device_remove_software_node(&client->dev); + device_unregister(&client->dev); +} +EXPORT_SYMBOL_GPL(i2c_unregister_device); + +/** + * i2c_find_device_by_fwnode() - find an i2c_client for the fwnode + * @fwnode: &struct fwnode_handle corresponding to the &struct i2c_client + * + * Look up and return the &struct i2c_client corresponding to the @fwnode. + * If no client can be found, or @fwnode is NULL, this returns NULL. + * + * The user must call put_device(&client->dev) once done with the i2c client. + */ +struct i2c_client *i2c_find_device_by_fwnode(struct fwnode_handle *fwnode) +{ + struct i2c_client *client; + struct device *dev; + + if (!fwnode) + return NULL; + + dev = bus_find_device_by_fwnode(&i2c_bus_type, fwnode); + if (!dev) + return NULL; + + client = i2c_verify_client(dev); + if (!client) + put_device(dev); + + return client; +} +EXPORT_SYMBOL(i2c_find_device_by_fwnode); + + +static const struct i2c_device_id dummy_id[] = { + { "dummy", 0 }, + { }, +}; + +static int dummy_probe(struct i2c_client *client) +{ + return 0; +} + +static struct i2c_driver dummy_driver = { + .driver.name = "dummy", + .probe = dummy_probe, + .id_table = dummy_id, +}; + +/** + * i2c_new_dummy_device - return a new i2c device bound to a dummy driver + * @adapter: the adapter managing the device + * @address: seven bit address to be used + * Context: can sleep + * + * This returns an I2C client bound to the "dummy" driver, intended for use + * with devices that consume multiple addresses. Examples of such chips + * include various EEPROMS (like 24c04 and 24c08 models). + * + * These dummy devices have two main uses. First, most I2C and SMBus calls + * except i2c_transfer() need a client handle; the dummy will be that handle. + * And second, this prevents the specified address from being bound to a + * different driver. + * + * This returns the new i2c client, which should be saved for later use with + * i2c_unregister_device(); or an ERR_PTR to describe the error. + */ +struct i2c_client *i2c_new_dummy_device(struct i2c_adapter *adapter, u16 address) +{ + struct i2c_board_info info = { + I2C_BOARD_INFO("dummy", address), + }; + + return i2c_new_client_device(adapter, &info); +} +EXPORT_SYMBOL_GPL(i2c_new_dummy_device); + +static void devm_i2c_release_dummy(void *client) +{ + i2c_unregister_device(client); +} + +/** + * devm_i2c_new_dummy_device - return a new i2c device bound to a dummy driver + * @dev: device the managed resource is bound to + * @adapter: the adapter managing the device + * @address: seven bit address to be used + * Context: can sleep + * + * This is the device-managed version of @i2c_new_dummy_device. It returns the + * new i2c client or an ERR_PTR in case of an error. + */ +struct i2c_client *devm_i2c_new_dummy_device(struct device *dev, + struct i2c_adapter *adapter, + u16 address) +{ + struct i2c_client *client; + int ret; + + client = i2c_new_dummy_device(adapter, address); + if (IS_ERR(client)) + return client; + + ret = devm_add_action_or_reset(dev, devm_i2c_release_dummy, client); + if (ret) + return ERR_PTR(ret); + + return client; +} +EXPORT_SYMBOL_GPL(devm_i2c_new_dummy_device); + +/** + * i2c_new_ancillary_device - Helper to get the instantiated secondary address + * and create the associated device + * @client: Handle to the primary client + * @name: Handle to specify which secondary address to get + * @default_addr: Used as a fallback if no secondary address was specified + * Context: can sleep + * + * I2C clients can be composed of multiple I2C slaves bound together in a single + * component. The I2C client driver then binds to the master I2C slave and needs + * to create I2C dummy clients to communicate with all the other slaves. + * + * This function creates and returns an I2C dummy client whose I2C address is + * retrieved from the platform firmware based on the given slave name. If no + * address is specified by the firmware default_addr is used. + * + * On DT-based platforms the address is retrieved from the "reg" property entry + * cell whose "reg-names" value matches the slave name. + * + * This returns the new i2c client, which should be saved for later use with + * i2c_unregister_device(); or an ERR_PTR to describe the error. + */ +struct i2c_client *i2c_new_ancillary_device(struct i2c_client *client, + const char *name, + u16 default_addr) +{ + struct device_node *np = client->dev.of_node; + u32 addr = default_addr; + int i; + + if (np) { + i = of_property_match_string(np, "reg-names", name); + if (i >= 0) + of_property_read_u32_index(np, "reg", i, &addr); + } + + dev_dbg(&client->adapter->dev, "Address for %s : 0x%x\n", name, addr); + return i2c_new_dummy_device(client->adapter, addr); +} +EXPORT_SYMBOL_GPL(i2c_new_ancillary_device); + +/* ------------------------------------------------------------------------- */ + +/* I2C bus adapters -- one roots each I2C or SMBUS segment */ + +static void i2c_adapter_dev_release(struct device *dev) +{ + struct i2c_adapter *adap = to_i2c_adapter(dev); + complete(&adap->dev_released); +} + +unsigned int i2c_adapter_depth(struct i2c_adapter *adapter) +{ + unsigned int depth = 0; + + while ((adapter = i2c_parent_is_i2c_adapter(adapter))) + depth++; + + WARN_ONCE(depth >= MAX_LOCKDEP_SUBCLASSES, + "adapter depth exceeds lockdep subclass limit\n"); + + return depth; +} +EXPORT_SYMBOL_GPL(i2c_adapter_depth); + +/* + * Let users instantiate I2C devices through sysfs. This can be used when + * platform initialization code doesn't contain the proper data for + * whatever reason. Also useful for drivers that do device detection and + * detection fails, either because the device uses an unexpected address, + * or this is a compatible device with different ID register values. + * + * Parameter checking may look overzealous, but we really don't want + * the user to provide incorrect parameters. + */ +static ssize_t +new_device_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i2c_adapter *adap = to_i2c_adapter(dev); + struct i2c_board_info info; + struct i2c_client *client; + char *blank, end; + int res; + + memset(&info, 0, sizeof(struct i2c_board_info)); + + blank = strchr(buf, ' '); + if (!blank) { + dev_err(dev, "%s: Missing parameters\n", "new_device"); + return -EINVAL; + } + if (blank - buf > I2C_NAME_SIZE - 1) { + dev_err(dev, "%s: Invalid device name\n", "new_device"); + return -EINVAL; + } + memcpy(info.type, buf, blank - buf); + + /* Parse remaining parameters, reject extra parameters */ + res = sscanf(++blank, "%hi%c", &info.addr, &end); + if (res < 1) { + dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); + return -EINVAL; + } + if (res > 1 && end != '\n') { + dev_err(dev, "%s: Extra parameters\n", "new_device"); + return -EINVAL; + } + + if ((info.addr & I2C_ADDR_OFFSET_TEN_BIT) == I2C_ADDR_OFFSET_TEN_BIT) { + info.addr &= ~I2C_ADDR_OFFSET_TEN_BIT; + info.flags |= I2C_CLIENT_TEN; + } + + if (info.addr & I2C_ADDR_OFFSET_SLAVE) { + info.addr &= ~I2C_ADDR_OFFSET_SLAVE; + info.flags |= I2C_CLIENT_SLAVE; + } + + client = i2c_new_client_device(adap, &info); + if (IS_ERR(client)) + return PTR_ERR(client); + + /* Keep track of the added device */ + mutex_lock(&adap->userspace_clients_lock); + list_add_tail(&client->detected, &adap->userspace_clients); + mutex_unlock(&adap->userspace_clients_lock); + dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", + info.type, info.addr); + + return count; +} +static DEVICE_ATTR_WO(new_device); + +/* + * And of course let the users delete the devices they instantiated, if + * they got it wrong. This interface can only be used to delete devices + * instantiated by i2c_sysfs_new_device above. This guarantees that we + * don't delete devices to which some kernel code still has references. + * + * Parameter checking may look overzealous, but we really don't want + * the user to delete the wrong device. + */ +static ssize_t +delete_device_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i2c_adapter *adap = to_i2c_adapter(dev); + struct i2c_client *client, *next; + unsigned short addr; + char end; + int res; + + /* Parse parameters, reject extra parameters */ + res = sscanf(buf, "%hi%c", &addr, &end); + if (res < 1) { + dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); + return -EINVAL; + } + if (res > 1 && end != '\n') { + dev_err(dev, "%s: Extra parameters\n", "delete_device"); + return -EINVAL; + } + + /* Make sure the device was added through sysfs */ + res = -ENOENT; + mutex_lock_nested(&adap->userspace_clients_lock, + i2c_adapter_depth(adap)); + list_for_each_entry_safe(client, next, &adap->userspace_clients, + detected) { + if (i2c_encode_flags_to_addr(client) == addr) { + dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", + "delete_device", client->name, client->addr); + + list_del(&client->detected); + i2c_unregister_device(client); + res = count; + break; + } + } + mutex_unlock(&adap->userspace_clients_lock); + + if (res < 0) + dev_err(dev, "%s: Can't find device in list\n", + "delete_device"); + return res; +} +static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, S_IWUSR, NULL, + delete_device_store); + +static struct attribute *i2c_adapter_attrs[] = { + &dev_attr_name.attr, + &dev_attr_new_device.attr, + &dev_attr_delete_device.attr, + NULL +}; +ATTRIBUTE_GROUPS(i2c_adapter); + +struct device_type i2c_adapter_type = { + .groups = i2c_adapter_groups, + .release = i2c_adapter_dev_release, +}; +EXPORT_SYMBOL_GPL(i2c_adapter_type); + +/** + * i2c_verify_adapter - return parameter as i2c_adapter or NULL + * @dev: device, probably from some driver model iterator + * + * When traversing the driver model tree, perhaps using driver model + * iterators like @device_for_each_child(), you can't assume very much + * about the nodes you find. Use this function to avoid oopses caused + * by wrongly treating some non-I2C device as an i2c_adapter. + */ +struct i2c_adapter *i2c_verify_adapter(struct device *dev) +{ + return (dev->type == &i2c_adapter_type) + ? to_i2c_adapter(dev) + : NULL; +} +EXPORT_SYMBOL(i2c_verify_adapter); + +#ifdef CONFIG_I2C_COMPAT +static struct class_compat *i2c_adapter_compat_class; +#endif + +static void i2c_scan_static_board_info(struct i2c_adapter *adapter) +{ + struct i2c_devinfo *devinfo; + + down_read(&__i2c_board_lock); + list_for_each_entry(devinfo, &__i2c_board_list, list) { + if (devinfo->busnum == adapter->nr && + IS_ERR(i2c_new_client_device(adapter, &devinfo->board_info))) + dev_err(&adapter->dev, + "Can't create device at 0x%02x\n", + devinfo->board_info.addr); + } + up_read(&__i2c_board_lock); +} + +static int i2c_do_add_adapter(struct i2c_driver *driver, + struct i2c_adapter *adap) +{ + /* Detect supported devices on that bus, and instantiate them */ + i2c_detect(adap, driver); + + return 0; +} + +static int __process_new_adapter(struct device_driver *d, void *data) +{ + return i2c_do_add_adapter(to_i2c_driver(d), data); +} + +static const struct i2c_lock_operations i2c_adapter_lock_ops = { + .lock_bus = i2c_adapter_lock_bus, + .trylock_bus = i2c_adapter_trylock_bus, + .unlock_bus = i2c_adapter_unlock_bus, +}; + +static void i2c_host_notify_irq_teardown(struct i2c_adapter *adap) +{ + struct irq_domain *domain = adap->host_notify_domain; + irq_hw_number_t hwirq; + + if (!domain) + return; + + for (hwirq = 0 ; hwirq < I2C_ADDR_7BITS_COUNT ; hwirq++) + irq_dispose_mapping(irq_find_mapping(domain, hwirq)); + + irq_domain_remove(domain); + adap->host_notify_domain = NULL; +} + +static int i2c_host_notify_irq_map(struct irq_domain *h, + unsigned int virq, + irq_hw_number_t hw_irq_num) +{ + irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq); + + return 0; +} + +static const struct irq_domain_ops i2c_host_notify_irq_ops = { + .map = i2c_host_notify_irq_map, +}; + +static int i2c_setup_host_notify_irq_domain(struct i2c_adapter *adap) +{ + struct irq_domain *domain; + + if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_HOST_NOTIFY)) + return 0; + + domain = irq_domain_create_linear(adap->dev.parent->fwnode, + I2C_ADDR_7BITS_COUNT, + &i2c_host_notify_irq_ops, adap); + if (!domain) + return -ENOMEM; + + adap->host_notify_domain = domain; + + return 0; +} + +/** + * i2c_handle_smbus_host_notify - Forward a Host Notify event to the correct + * I2C client. + * @adap: the adapter + * @addr: the I2C address of the notifying device + * Context: can't sleep + * + * Helper function to be called from an I2C bus driver's interrupt + * handler. It will schedule the Host Notify IRQ. + */ +int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr) +{ + int irq; + + if (!adap) + return -EINVAL; + + irq = irq_find_mapping(adap->host_notify_domain, addr); + if (irq <= 0) + return -ENXIO; + + generic_handle_irq_safe(irq); + + return 0; +} +EXPORT_SYMBOL_GPL(i2c_handle_smbus_host_notify); + +static int i2c_register_adapter(struct i2c_adapter *adap) +{ + int res = -EINVAL; + + /* Can't register until after driver model init */ + if (WARN_ON(!is_registered)) { + res = -EAGAIN; + goto out_list; + } + + /* Sanity checks */ + if (WARN(!adap->name[0], "i2c adapter has no name")) + goto out_list; + + if (!adap->algo) { + pr_err("adapter '%s': no algo supplied!\n", adap->name); + goto out_list; + } + + if (!adap->lock_ops) + adap->lock_ops = &i2c_adapter_lock_ops; + + adap->locked_flags = 0; + rt_mutex_init(&adap->bus_lock); + rt_mutex_init(&adap->mux_lock); + mutex_init(&adap->userspace_clients_lock); + INIT_LIST_HEAD(&adap->userspace_clients); + + /* Set default timeout to 1 second if not already set */ + if (adap->timeout == 0) + adap->timeout = HZ; + + /* register soft irqs for Host Notify */ + res = i2c_setup_host_notify_irq_domain(adap); + if (res) { + pr_err("adapter '%s': can't create Host Notify IRQs (%d)\n", + adap->name, res); + goto out_list; + } + + dev_set_name(&adap->dev, "i2c-%d", adap->nr); + adap->dev.bus = &i2c_bus_type; + adap->dev.type = &i2c_adapter_type; + res = device_register(&adap->dev); + if (res) { + pr_err("adapter '%s': can't register device (%d)\n", adap->name, res); + goto out_list; + } + + res = i2c_setup_smbus_alert(adap); + if (res) + goto out_reg; + + device_enable_async_suspend(&adap->dev); + pm_runtime_no_callbacks(&adap->dev); + pm_suspend_ignore_children(&adap->dev, true); + pm_runtime_enable(&adap->dev); + + res = i2c_init_recovery(adap); + if (res == -EPROBE_DEFER) + goto out_reg; + + dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); + +#ifdef CONFIG_I2C_COMPAT + res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, + adap->dev.parent); + if (res) + dev_warn(&adap->dev, + "Failed to create compatibility class link\n"); +#endif + + /* create pre-declared device nodes */ + of_i2c_register_devices(adap); + i2c_acpi_install_space_handler(adap); + i2c_acpi_register_devices(adap); + + if (adap->nr < __i2c_first_dynamic_bus_num) + i2c_scan_static_board_info(adap); + + /* Notify drivers */ + mutex_lock(&core_lock); + bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); + mutex_unlock(&core_lock); + + return 0; + +out_reg: + init_completion(&adap->dev_released); + device_unregister(&adap->dev); + wait_for_completion(&adap->dev_released); +out_list: + mutex_lock(&core_lock); + idr_remove(&i2c_adapter_idr, adap->nr); + mutex_unlock(&core_lock); + return res; +} + +/** + * __i2c_add_numbered_adapter - i2c_add_numbered_adapter where nr is never -1 + * @adap: the adapter to register (with adap->nr initialized) + * Context: can sleep + * + * See i2c_add_numbered_adapter() for details. + */ +static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) +{ + int id; + + mutex_lock(&core_lock); + id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, GFP_KERNEL); + mutex_unlock(&core_lock); + if (WARN(id < 0, "couldn't get idr")) + return id == -ENOSPC ? -EBUSY : id; + + return i2c_register_adapter(adap); +} + +/** + * i2c_add_adapter - declare i2c adapter, use dynamic bus number + * @adapter: the adapter to add + * Context: can sleep + * + * This routine is used to declare an I2C adapter when its bus number + * doesn't matter or when its bus number is specified by an dt alias. + * Examples of bases when the bus number doesn't matter: I2C adapters + * dynamically added by USB links or PCI plugin cards. + * + * When this returns zero, a new bus number was allocated and stored + * in adap->nr, and the specified adapter became available for clients. + * Otherwise, a negative errno value is returned. + */ +int i2c_add_adapter(struct i2c_adapter *adapter) +{ + struct device *dev = &adapter->dev; + int id; + + if (dev->of_node) { + id = of_alias_get_id(dev->of_node, "i2c"); + if (id >= 0) { + adapter->nr = id; + return __i2c_add_numbered_adapter(adapter); + } + } + + mutex_lock(&core_lock); + id = idr_alloc(&i2c_adapter_idr, adapter, + __i2c_first_dynamic_bus_num, 0, GFP_KERNEL); + mutex_unlock(&core_lock); + if (WARN(id < 0, "couldn't get idr")) + return id; + + adapter->nr = id; + + return i2c_register_adapter(adapter); +} +EXPORT_SYMBOL(i2c_add_adapter); + +/** + * i2c_add_numbered_adapter - declare i2c adapter, use static bus number + * @adap: the adapter to register (with adap->nr initialized) + * Context: can sleep + * + * This routine is used to declare an I2C adapter when its bus number + * matters. For example, use it for I2C adapters from system-on-chip CPUs, + * or otherwise built in to the system's mainboard, and where i2c_board_info + * is used to properly configure I2C devices. + * + * If the requested bus number is set to -1, then this function will behave + * identically to i2c_add_adapter, and will dynamically assign a bus number. + * + * If no devices have pre-been declared for this bus, then be sure to + * register the adapter before any dynamically allocated ones. Otherwise + * the required bus ID may not be available. + * + * When this returns zero, the specified adapter became available for + * clients using the bus number provided in adap->nr. Also, the table + * of I2C devices pre-declared using i2c_register_board_info() is scanned, + * and the appropriate driver model device nodes are created. Otherwise, a + * negative errno value is returned. + */ +int i2c_add_numbered_adapter(struct i2c_adapter *adap) +{ + if (adap->nr == -1) /* -1 means dynamically assign bus id */ + return i2c_add_adapter(adap); + + return __i2c_add_numbered_adapter(adap); +} +EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); + +static void i2c_do_del_adapter(struct i2c_driver *driver, + struct i2c_adapter *adapter) +{ + struct i2c_client *client, *_n; + + /* Remove the devices we created ourselves as the result of hardware + * probing (using a driver's detect method) */ + list_for_each_entry_safe(client, _n, &driver->clients, detected) { + if (client->adapter == adapter) { + dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", + client->name, client->addr); + list_del(&client->detected); + i2c_unregister_device(client); + } + } +} + +static int __unregister_client(struct device *dev, void *dummy) +{ + struct i2c_client *client = i2c_verify_client(dev); + if (client && strcmp(client->name, "dummy")) + i2c_unregister_device(client); + return 0; +} + +static int __unregister_dummy(struct device *dev, void *dummy) +{ + struct i2c_client *client = i2c_verify_client(dev); + i2c_unregister_device(client); + return 0; +} + +static int __process_removed_adapter(struct device_driver *d, void *data) +{ + i2c_do_del_adapter(to_i2c_driver(d), data); + return 0; +} + +/** + * i2c_del_adapter - unregister I2C adapter + * @adap: the adapter being unregistered + * Context: can sleep + * + * This unregisters an I2C adapter which was previously registered + * by @i2c_add_adapter or @i2c_add_numbered_adapter. + */ +void i2c_del_adapter(struct i2c_adapter *adap) +{ + struct i2c_adapter *found; + struct i2c_client *client, *next; + + /* First make sure that this adapter was ever added */ + mutex_lock(&core_lock); + found = idr_find(&i2c_adapter_idr, adap->nr); + mutex_unlock(&core_lock); + if (found != adap) { + pr_debug("attempting to delete unregistered adapter [%s]\n", adap->name); + return; + } + + i2c_acpi_remove_space_handler(adap); + /* Tell drivers about this removal */ + mutex_lock(&core_lock); + bus_for_each_drv(&i2c_bus_type, NULL, adap, + __process_removed_adapter); + mutex_unlock(&core_lock); + + /* Remove devices instantiated from sysfs */ + mutex_lock_nested(&adap->userspace_clients_lock, + i2c_adapter_depth(adap)); + list_for_each_entry_safe(client, next, &adap->userspace_clients, + detected) { + dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, + client->addr); + list_del(&client->detected); + i2c_unregister_device(client); + } + mutex_unlock(&adap->userspace_clients_lock); + + /* Detach any active clients. This can't fail, thus we do not + * check the returned value. This is a two-pass process, because + * we can't remove the dummy devices during the first pass: they + * could have been instantiated by real devices wishing to clean + * them up properly, so we give them a chance to do that first. */ + device_for_each_child(&adap->dev, NULL, __unregister_client); + device_for_each_child(&adap->dev, NULL, __unregister_dummy); + +#ifdef CONFIG_I2C_COMPAT + class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, + adap->dev.parent); +#endif + + /* device name is gone after device_unregister */ + dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); + + pm_runtime_disable(&adap->dev); + + i2c_host_notify_irq_teardown(adap); + + /* wait until all references to the device are gone + * + * FIXME: This is old code and should ideally be replaced by an + * alternative which results in decoupling the lifetime of the struct + * device from the i2c_adapter, like spi or netdev do. Any solution + * should be thoroughly tested with DEBUG_KOBJECT_RELEASE enabled! + */ + init_completion(&adap->dev_released); + device_unregister(&adap->dev); + wait_for_completion(&adap->dev_released); + + /* free bus id */ + mutex_lock(&core_lock); + idr_remove(&i2c_adapter_idr, adap->nr); + mutex_unlock(&core_lock); + + /* Clear the device structure in case this adapter is ever going to be + added again */ + memset(&adap->dev, 0, sizeof(adap->dev)); +} +EXPORT_SYMBOL(i2c_del_adapter); + +static void devm_i2c_del_adapter(void *adapter) +{ + i2c_del_adapter(adapter); +} + +/** + * devm_i2c_add_adapter - device-managed variant of i2c_add_adapter() + * @dev: managing device for adding this I2C adapter + * @adapter: the adapter to add + * Context: can sleep + * + * Add adapter with dynamic bus number, same with i2c_add_adapter() + * but the adapter will be auto deleted on driver detach. + */ +int devm_i2c_add_adapter(struct device *dev, struct i2c_adapter *adapter) +{ + int ret; + + ret = i2c_add_adapter(adapter); + if (ret) + return ret; + + return devm_add_action_or_reset(dev, devm_i2c_del_adapter, adapter); +} +EXPORT_SYMBOL_GPL(devm_i2c_add_adapter); + +static int i2c_dev_or_parent_fwnode_match(struct device *dev, const void *data) +{ + if (dev_fwnode(dev) == data) + return 1; + + if (dev->parent && dev_fwnode(dev->parent) == data) + return 1; + + return 0; +} + +/** + * i2c_find_adapter_by_fwnode() - find an i2c_adapter for the fwnode + * @fwnode: &struct fwnode_handle corresponding to the &struct i2c_adapter + * + * Look up and return the &struct i2c_adapter corresponding to the @fwnode. + * If no adapter can be found, or @fwnode is NULL, this returns NULL. + * + * The user must call put_device(&adapter->dev) once done with the i2c adapter. + */ +struct i2c_adapter *i2c_find_adapter_by_fwnode(struct fwnode_handle *fwnode) +{ + struct i2c_adapter *adapter; + struct device *dev; + + if (!fwnode) + return NULL; + + dev = bus_find_device(&i2c_bus_type, NULL, fwnode, + i2c_dev_or_parent_fwnode_match); + if (!dev) + return NULL; + + adapter = i2c_verify_adapter(dev); + if (!adapter) + put_device(dev); + + return adapter; +} +EXPORT_SYMBOL(i2c_find_adapter_by_fwnode); + +/** + * i2c_get_adapter_by_fwnode() - find an i2c_adapter for the fwnode + * @fwnode: &struct fwnode_handle corresponding to the &struct i2c_adapter + * + * Look up and return the &struct i2c_adapter corresponding to the @fwnode, + * and increment the adapter module's use count. If no adapter can be found, + * or @fwnode is NULL, this returns NULL. + * + * The user must call i2c_put_adapter(adapter) once done with the i2c adapter. + * Note that this is different from i2c_find_adapter_by_node(). + */ +struct i2c_adapter *i2c_get_adapter_by_fwnode(struct fwnode_handle *fwnode) +{ + struct i2c_adapter *adapter; + + adapter = i2c_find_adapter_by_fwnode(fwnode); + if (!adapter) + return NULL; + + if (!try_module_get(adapter->owner)) { + put_device(&adapter->dev); + adapter = NULL; + } + + return adapter; +} +EXPORT_SYMBOL(i2c_get_adapter_by_fwnode); + +static void i2c_parse_timing(struct device *dev, char *prop_name, u32 *cur_val_p, + u32 def_val, bool use_def) +{ + int ret; + + ret = device_property_read_u32(dev, prop_name, cur_val_p); + if (ret && use_def) + *cur_val_p = def_val; + + dev_dbg(dev, "%s: %u\n", prop_name, *cur_val_p); +} + +/** + * i2c_parse_fw_timings - get I2C related timing parameters from firmware + * @dev: The device to scan for I2C timing properties + * @t: the i2c_timings struct to be filled with values + * @use_defaults: bool to use sane defaults derived from the I2C specification + * when properties are not found, otherwise don't update + * + * Scan the device for the generic I2C properties describing timing parameters + * for the signal and fill the given struct with the results. If a property was + * not found and use_defaults was true, then maximum timings are assumed which + * are derived from the I2C specification. If use_defaults is not used, the + * results will be as before, so drivers can apply their own defaults before + * calling this helper. The latter is mainly intended for avoiding regressions + * of existing drivers which want to switch to this function. New drivers + * almost always should use the defaults. + */ +void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults) +{ + bool u = use_defaults; + u32 d; + + i2c_parse_timing(dev, "clock-frequency", &t->bus_freq_hz, + I2C_MAX_STANDARD_MODE_FREQ, u); + + d = t->bus_freq_hz <= I2C_MAX_STANDARD_MODE_FREQ ? 1000 : + t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ ? 300 : 120; + i2c_parse_timing(dev, "i2c-scl-rising-time-ns", &t->scl_rise_ns, d, u); + + d = t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ ? 300 : 120; + i2c_parse_timing(dev, "i2c-scl-falling-time-ns", &t->scl_fall_ns, d, u); + + i2c_parse_timing(dev, "i2c-scl-internal-delay-ns", + &t->scl_int_delay_ns, 0, u); + i2c_parse_timing(dev, "i2c-sda-falling-time-ns", &t->sda_fall_ns, + t->scl_fall_ns, u); + i2c_parse_timing(dev, "i2c-sda-hold-time-ns", &t->sda_hold_ns, 0, u); + i2c_parse_timing(dev, "i2c-digital-filter-width-ns", + &t->digital_filter_width_ns, 0, u); + i2c_parse_timing(dev, "i2c-analog-filter-cutoff-frequency", + &t->analog_filter_cutoff_freq_hz, 0, u); +} +EXPORT_SYMBOL_GPL(i2c_parse_fw_timings); + +/* ------------------------------------------------------------------------- */ + +int i2c_for_each_dev(void *data, int (*fn)(struct device *dev, void *data)) +{ + int res; + + mutex_lock(&core_lock); + res = bus_for_each_dev(&i2c_bus_type, NULL, data, fn); + mutex_unlock(&core_lock); + + return res; +} +EXPORT_SYMBOL_GPL(i2c_for_each_dev); + +static int __process_new_driver(struct device *dev, void *data) +{ + if (dev->type != &i2c_adapter_type) + return 0; + return i2c_do_add_adapter(data, to_i2c_adapter(dev)); +} + +/* + * An i2c_driver is used with one or more i2c_client (device) nodes to access + * i2c slave chips, on a bus instance associated with some i2c_adapter. + */ + +int i2c_register_driver(struct module *owner, struct i2c_driver *driver) +{ + int res; + + /* Can't register until after driver model init */ + if (WARN_ON(!is_registered)) + return -EAGAIN; + + /* add the driver to the list of i2c drivers in the driver core */ + driver->driver.owner = owner; + driver->driver.bus = &i2c_bus_type; + INIT_LIST_HEAD(&driver->clients); + + /* When registration returns, the driver core + * will have called probe() for all matching-but-unbound devices. + */ + res = driver_register(&driver->driver); + if (res) + return res; + + pr_debug("driver [%s] registered\n", driver->driver.name); + + /* Walk the adapters that are already present */ + i2c_for_each_dev(driver, __process_new_driver); + + return 0; +} +EXPORT_SYMBOL(i2c_register_driver); + +static int __process_removed_driver(struct device *dev, void *data) +{ + if (dev->type == &i2c_adapter_type) + i2c_do_del_adapter(data, to_i2c_adapter(dev)); + return 0; +} + +/** + * i2c_del_driver - unregister I2C driver + * @driver: the driver being unregistered + * Context: can sleep + */ +void i2c_del_driver(struct i2c_driver *driver) +{ + i2c_for_each_dev(driver, __process_removed_driver); + + driver_unregister(&driver->driver); + pr_debug("driver [%s] unregistered\n", driver->driver.name); +} +EXPORT_SYMBOL(i2c_del_driver); + +/* ------------------------------------------------------------------------- */ + +struct i2c_cmd_arg { + unsigned cmd; + void *arg; +}; + +static int i2c_cmd(struct device *dev, void *_arg) +{ + struct i2c_client *client = i2c_verify_client(dev); + struct i2c_cmd_arg *arg = _arg; + struct i2c_driver *driver; + + if (!client || !client->dev.driver) + return 0; + + driver = to_i2c_driver(client->dev.driver); + if (driver->command) + driver->command(client, arg->cmd, arg->arg); + return 0; +} + +void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) +{ + struct i2c_cmd_arg cmd_arg; + + cmd_arg.cmd = cmd; + cmd_arg.arg = arg; + device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); +} +EXPORT_SYMBOL(i2c_clients_command); + +static int __init i2c_init(void) +{ + int retval; + + retval = of_alias_get_highest_id("i2c"); + + down_write(&__i2c_board_lock); + if (retval >= __i2c_first_dynamic_bus_num) + __i2c_first_dynamic_bus_num = retval + 1; + up_write(&__i2c_board_lock); + + retval = bus_register(&i2c_bus_type); + if (retval) + return retval; + + is_registered = true; + +#ifdef CONFIG_I2C_COMPAT + i2c_adapter_compat_class = class_compat_register("i2c-adapter"); + if (!i2c_adapter_compat_class) { + retval = -ENOMEM; + goto bus_err; + } +#endif + retval = i2c_add_driver(&dummy_driver); + if (retval) + goto class_err; + + if (IS_ENABLED(CONFIG_OF_DYNAMIC)) + WARN_ON(of_reconfig_notifier_register(&i2c_of_notifier)); + if (IS_ENABLED(CONFIG_ACPI)) + WARN_ON(acpi_reconfig_notifier_register(&i2c_acpi_notifier)); + + return 0; + +class_err: +#ifdef CONFIG_I2C_COMPAT + class_compat_unregister(i2c_adapter_compat_class); +bus_err: +#endif + is_registered = false; + bus_unregister(&i2c_bus_type); + return retval; +} + +static void __exit i2c_exit(void) +{ + if (IS_ENABLED(CONFIG_ACPI)) + WARN_ON(acpi_reconfig_notifier_unregister(&i2c_acpi_notifier)); + if (IS_ENABLED(CONFIG_OF_DYNAMIC)) + WARN_ON(of_reconfig_notifier_unregister(&i2c_of_notifier)); + i2c_del_driver(&dummy_driver); +#ifdef CONFIG_I2C_COMPAT + class_compat_unregister(i2c_adapter_compat_class); +#endif + bus_unregister(&i2c_bus_type); + tracepoint_synchronize_unregister(); +} + +/* We must initialize early, because some subsystems register i2c drivers + * in subsys_initcall() code, but are linked (and initialized) before i2c. + */ +postcore_initcall(i2c_init); +module_exit(i2c_exit); + +/* ---------------------------------------------------- + * the functional interface to the i2c busses. + * ---------------------------------------------------- + */ + +/* Check if val is exceeding the quirk IFF quirk is non 0 */ +#define i2c_quirk_exceeded(val, quirk) ((quirk) && ((val) > (quirk))) + +static int i2c_quirk_error(struct i2c_adapter *adap, struct i2c_msg *msg, char *err_msg) +{ + dev_err_ratelimited(&adap->dev, "adapter quirk: %s (addr 0x%04x, size %u, %s)\n", + err_msg, msg->addr, msg->len, + msg->flags & I2C_M_RD ? "read" : "write"); + return -EOPNOTSUPP; +} + +static int i2c_check_for_quirks(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + const struct i2c_adapter_quirks *q = adap->quirks; + int max_num = q->max_num_msgs, i; + bool do_len_check = true; + + if (q->flags & I2C_AQ_COMB) { + max_num = 2; + + /* special checks for combined messages */ + if (num == 2) { + if (q->flags & I2C_AQ_COMB_WRITE_FIRST && msgs[0].flags & I2C_M_RD) + return i2c_quirk_error(adap, &msgs[0], "1st comb msg must be write"); + + if (q->flags & I2C_AQ_COMB_READ_SECOND && !(msgs[1].flags & I2C_M_RD)) + return i2c_quirk_error(adap, &msgs[1], "2nd comb msg must be read"); + + if (q->flags & I2C_AQ_COMB_SAME_ADDR && msgs[0].addr != msgs[1].addr) + return i2c_quirk_error(adap, &msgs[0], "comb msg only to same addr"); + + if (i2c_quirk_exceeded(msgs[0].len, q->max_comb_1st_msg_len)) + return i2c_quirk_error(adap, &msgs[0], "msg too long"); + + if (i2c_quirk_exceeded(msgs[1].len, q->max_comb_2nd_msg_len)) + return i2c_quirk_error(adap, &msgs[1], "msg too long"); + + do_len_check = false; + } + } + + if (i2c_quirk_exceeded(num, max_num)) + return i2c_quirk_error(adap, &msgs[0], "too many messages"); + + for (i = 0; i < num; i++) { + u16 len = msgs[i].len; + + if (msgs[i].flags & I2C_M_RD) { + if (do_len_check && i2c_quirk_exceeded(len, q->max_read_len)) + return i2c_quirk_error(adap, &msgs[i], "msg too long"); + + if (q->flags & I2C_AQ_NO_ZERO_LEN_READ && len == 0) + return i2c_quirk_error(adap, &msgs[i], "no zero length"); + } else { + if (do_len_check && i2c_quirk_exceeded(len, q->max_write_len)) + return i2c_quirk_error(adap, &msgs[i], "msg too long"); + + if (q->flags & I2C_AQ_NO_ZERO_LEN_WRITE && len == 0) + return i2c_quirk_error(adap, &msgs[i], "no zero length"); + } + } + + return 0; +} + +/** + * __i2c_transfer - unlocked flavor of i2c_transfer + * @adap: Handle to I2C bus + * @msgs: One or more messages to execute before STOP is issued to + * terminate the operation; each message begins with a START. + * @num: Number of messages to be executed. + * + * Returns negative errno, else the number of messages executed. + * + * Adapter lock must be held when calling this function. No debug logging + * takes place. adap->algo->master_xfer existence isn't checked. + */ +int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + unsigned long orig_jiffies; + int ret, try; + + if (WARN_ON(!msgs || num < 1)) + return -EINVAL; + + ret = __i2c_check_suspended(adap); + if (ret) + return ret; + + if (adap->quirks && i2c_check_for_quirks(adap, msgs, num)) + return -EOPNOTSUPP; + + /* + * i2c_trace_msg_key gets enabled when tracepoint i2c_transfer gets + * enabled. This is an efficient way of keeping the for-loop from + * being executed when not needed. + */ + if (static_branch_unlikely(&i2c_trace_msg_key)) { + int i; + for (i = 0; i < num; i++) + if (msgs[i].flags & I2C_M_RD) + trace_i2c_read(adap, &msgs[i], i); + else + trace_i2c_write(adap, &msgs[i], i); + } + + /* Retry automatically on arbitration loss */ + orig_jiffies = jiffies; + for (ret = 0, try = 0; try <= adap->retries; try++) { + if (i2c_in_atomic_xfer_mode() && adap->algo->master_xfer_atomic) + ret = adap->algo->master_xfer_atomic(adap, msgs, num); + else + ret = adap->algo->master_xfer(adap, msgs, num); + + if (ret != -EAGAIN) + break; + if (time_after(jiffies, orig_jiffies + adap->timeout)) + break; + } + + if (static_branch_unlikely(&i2c_trace_msg_key)) { + int i; + for (i = 0; i < ret; i++) + if (msgs[i].flags & I2C_M_RD) + trace_i2c_reply(adap, &msgs[i], i); + trace_i2c_result(adap, num, ret); + } + + return ret; +} +EXPORT_SYMBOL(__i2c_transfer); + +/** + * i2c_transfer - execute a single or combined I2C message + * @adap: Handle to I2C bus + * @msgs: One or more messages to execute before STOP is issued to + * terminate the operation; each message begins with a START. + * @num: Number of messages to be executed. + * + * Returns negative errno, else the number of messages executed. + * + * Note that there is no requirement that each message be sent to + * the same slave address, although that is the most common model. + */ +int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + int ret; + + if (!adap->algo->master_xfer) { + dev_dbg(&adap->dev, "I2C level transfers not supported\n"); + return -EOPNOTSUPP; + } + + /* REVISIT the fault reporting model here is weak: + * + * - When we get an error after receiving N bytes from a slave, + * there is no way to report "N". + * + * - When we get a NAK after transmitting N bytes to a slave, + * there is no way to report "N" ... or to let the master + * continue executing the rest of this combined message, if + * that's the appropriate response. + * + * - When for example "num" is two and we successfully complete + * the first message but get an error part way through the + * second, it's unclear whether that should be reported as + * one (discarding status on the second message) or errno + * (discarding status on the first one). + */ + ret = __i2c_lock_bus_helper(adap); + if (ret) + return ret; + + ret = __i2c_transfer(adap, msgs, num); + i2c_unlock_bus(adap, I2C_LOCK_SEGMENT); + + return ret; +} +EXPORT_SYMBOL(i2c_transfer); + +/** + * i2c_transfer_buffer_flags - issue a single I2C message transferring data + * to/from a buffer + * @client: Handle to slave device + * @buf: Where the data is stored + * @count: How many bytes to transfer, must be less than 64k since msg.len is u16 + * @flags: The flags to be used for the message, e.g. I2C_M_RD for reads + * + * Returns negative errno, or else the number of bytes transferred. + */ +int i2c_transfer_buffer_flags(const struct i2c_client *client, char *buf, + int count, u16 flags) +{ + int ret; + struct i2c_msg msg = { + .addr = client->addr, + .flags = flags | (client->flags & I2C_M_TEN), + .len = count, + .buf = buf, + }; + + ret = i2c_transfer(client->adapter, &msg, 1); + + /* + * If everything went ok (i.e. 1 msg transferred), return #bytes + * transferred, else error code. + */ + return (ret == 1) ? count : ret; +} +EXPORT_SYMBOL(i2c_transfer_buffer_flags); + +/** + * i2c_get_device_id - get manufacturer, part id and die revision of a device + * @client: The device to query + * @id: The queried information + * + * Returns negative errno on error, zero on success. + */ +int i2c_get_device_id(const struct i2c_client *client, + struct i2c_device_identity *id) +{ + struct i2c_adapter *adap = client->adapter; + union i2c_smbus_data raw_id; + int ret; + + if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) + return -EOPNOTSUPP; + + raw_id.block[0] = 3; + ret = i2c_smbus_xfer(adap, I2C_ADDR_DEVICE_ID, 0, + I2C_SMBUS_READ, client->addr << 1, + I2C_SMBUS_I2C_BLOCK_DATA, &raw_id); + if (ret) + return ret; + + id->manufacturer_id = (raw_id.block[1] << 4) | (raw_id.block[2] >> 4); + id->part_id = ((raw_id.block[2] & 0xf) << 5) | (raw_id.block[3] >> 3); + id->die_revision = raw_id.block[3] & 0x7; + return 0; +} +EXPORT_SYMBOL_GPL(i2c_get_device_id); + +/** + * i2c_client_get_device_id - get the driver match table entry of a device + * @client: the device to query. The device must be bound to a driver + * + * Returns a pointer to the matching entry if found, NULL otherwise. + */ +const struct i2c_device_id *i2c_client_get_device_id(const struct i2c_client *client) +{ + const struct i2c_driver *drv = to_i2c_driver(client->dev.driver); + + return i2c_match_id(drv->id_table, client); +} +EXPORT_SYMBOL_GPL(i2c_client_get_device_id); + +/* ---------------------------------------------------- + * the i2c address scanning function + * Will not work for 10-bit addresses! + * ---------------------------------------------------- + */ + +/* + * Legacy default probe function, mostly relevant for SMBus. The default + * probe method is a quick write, but it is known to corrupt the 24RF08 + * EEPROMs due to a state machine bug, and could also irreversibly + * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, + * we use a short byte read instead. Also, some bus drivers don't implement + * quick write, so we fallback to a byte read in that case too. + * On x86, there is another special case for FSC hardware monitoring chips, + * which want regular byte reads (address 0x73.) Fortunately, these are the + * only known chips using this I2C address on PC hardware. + * Returns 1 if probe succeeded, 0 if not. + */ +static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) +{ + int err; + union i2c_smbus_data dummy; + +#ifdef CONFIG_X86 + if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) + && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) + err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, + I2C_SMBUS_BYTE_DATA, &dummy); + else +#endif + if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) + && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) + err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, + I2C_SMBUS_QUICK, NULL); + else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) + err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, + I2C_SMBUS_BYTE, &dummy); + else { + dev_warn(&adap->dev, "No suitable probing method supported for address 0x%02X\n", + addr); + err = -EOPNOTSUPP; + } + + return err >= 0; +} + +static int i2c_detect_address(struct i2c_client *temp_client, + struct i2c_driver *driver) +{ + struct i2c_board_info info; + struct i2c_adapter *adapter = temp_client->adapter; + int addr = temp_client->addr; + int err; + + /* Make sure the address is valid */ + err = i2c_check_7bit_addr_validity_strict(addr); + if (err) { + dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", + addr); + return err; + } + + /* Skip if already in use (7 bit, no need to encode flags) */ + if (i2c_check_addr_busy(adapter, addr)) + return 0; + + /* Make sure there is something at this address */ + if (!i2c_default_probe(adapter, addr)) + return 0; + + /* Finally call the custom detection function */ + memset(&info, 0, sizeof(struct i2c_board_info)); + info.addr = addr; + err = driver->detect(temp_client, &info); + if (err) { + /* -ENODEV is returned if the detection fails. We catch it + here as this isn't an error. */ + return err == -ENODEV ? 0 : err; + } + + /* Consistency check */ + if (info.type[0] == '\0') { + dev_err(&adapter->dev, + "%s detection function provided no name for 0x%x\n", + driver->driver.name, addr); + } else { + struct i2c_client *client; + + /* Detection succeeded, instantiate the device */ + if (adapter->class & I2C_CLASS_DEPRECATED) + dev_warn(&adapter->dev, + "This adapter will soon drop class based instantiation of devices. " + "Please make sure client 0x%02x gets instantiated by other means. " + "Check 'Documentation/i2c/instantiating-devices.rst' for details.\n", + info.addr); + + dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", + info.type, info.addr); + client = i2c_new_client_device(adapter, &info); + if (!IS_ERR(client)) + list_add_tail(&client->detected, &driver->clients); + else + dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", + info.type, info.addr); + } + return 0; +} + +static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) +{ + const unsigned short *address_list; + struct i2c_client *temp_client; + int i, err = 0; + + address_list = driver->address_list; + if (!driver->detect || !address_list) + return 0; + + /* Warn that the adapter lost class based instantiation */ + if (adapter->class == I2C_CLASS_DEPRECATED) { + dev_dbg(&adapter->dev, + "This adapter dropped support for I2C classes and won't auto-detect %s devices anymore. " + "If you need it, check 'Documentation/i2c/instantiating-devices.rst' for alternatives.\n", + driver->driver.name); + return 0; + } + + /* Stop here if the classes do not match */ + if (!(adapter->class & driver->class)) + return 0; + + /* Set up a temporary client to help detect callback */ + temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); + if (!temp_client) + return -ENOMEM; + temp_client->adapter = adapter; + + for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { + dev_dbg(&adapter->dev, + "found normal entry for adapter %d, addr 0x%02x\n", + i2c_adapter_id(adapter), address_list[i]); + temp_client->addr = address_list[i]; + err = i2c_detect_address(temp_client, driver); + if (unlikely(err)) + break; + } + + kfree(temp_client); + return err; +} + +int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) +{ + return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, + I2C_SMBUS_QUICK, NULL) >= 0; +} +EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); + +struct i2c_client * +i2c_new_scanned_device(struct i2c_adapter *adap, + struct i2c_board_info *info, + unsigned short const *addr_list, + int (*probe)(struct i2c_adapter *adap, unsigned short addr)) +{ + int i; + + if (!probe) + probe = i2c_default_probe; + + for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { + /* Check address validity */ + if (i2c_check_7bit_addr_validity_strict(addr_list[i]) < 0) { + dev_warn(&adap->dev, "Invalid 7-bit address 0x%02x\n", + addr_list[i]); + continue; + } + + /* Check address availability (7 bit, no need to encode flags) */ + if (i2c_check_addr_busy(adap, addr_list[i])) { + dev_dbg(&adap->dev, + "Address 0x%02x already in use, not probing\n", + addr_list[i]); + continue; + } + + /* Test address responsiveness */ + if (probe(adap, addr_list[i])) + break; + } + + if (addr_list[i] == I2C_CLIENT_END) { + dev_dbg(&adap->dev, "Probing failed, no device found\n"); + return ERR_PTR(-ENODEV); + } + + info->addr = addr_list[i]; + return i2c_new_client_device(adap, info); +} +EXPORT_SYMBOL_GPL(i2c_new_scanned_device); + +struct i2c_adapter *i2c_get_adapter(int nr) +{ + struct i2c_adapter *adapter; + + mutex_lock(&core_lock); + adapter = idr_find(&i2c_adapter_idr, nr); + if (!adapter) + goto exit; + + if (try_module_get(adapter->owner)) + get_device(&adapter->dev); + else + adapter = NULL; + + exit: + mutex_unlock(&core_lock); + return adapter; +} +EXPORT_SYMBOL(i2c_get_adapter); + +void i2c_put_adapter(struct i2c_adapter *adap) +{ + if (!adap) + return; + + module_put(adap->owner); + /* Should be last, otherwise we risk use-after-free with 'adap' */ + put_device(&adap->dev); +} +EXPORT_SYMBOL(i2c_put_adapter); + +/** + * i2c_get_dma_safe_msg_buf() - get a DMA safe buffer for the given i2c_msg + * @msg: the message to be checked + * @threshold: the minimum number of bytes for which using DMA makes sense. + * Should at least be 1. + * + * Return: NULL if a DMA safe buffer was not obtained. Use msg->buf with PIO. + * Or a valid pointer to be used with DMA. After use, release it by + * calling i2c_put_dma_safe_msg_buf(). + * + * This function must only be called from process context! + */ +u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold) +{ + /* also skip 0-length msgs for bogus thresholds of 0 */ + if (!threshold) + pr_debug("DMA buffer for addr=0x%02x with length 0 is bogus\n", + msg->addr); + if (msg->len < threshold || msg->len == 0) + return NULL; + + if (msg->flags & I2C_M_DMA_SAFE) + return msg->buf; + + pr_debug("using bounce buffer for addr=0x%02x, len=%d\n", + msg->addr, msg->len); + + if (msg->flags & I2C_M_RD) + return kzalloc(msg->len, GFP_KERNEL); + else + return kmemdup(msg->buf, msg->len, GFP_KERNEL); +} +EXPORT_SYMBOL_GPL(i2c_get_dma_safe_msg_buf); + +/** + * i2c_put_dma_safe_msg_buf - release DMA safe buffer and sync with i2c_msg + * @buf: the buffer obtained from i2c_get_dma_safe_msg_buf(). May be NULL. + * @msg: the message which the buffer corresponds to + * @xferred: bool saying if the message was transferred + */ +void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred) +{ + if (!buf || buf == msg->buf) + return; + + if (xferred && msg->flags & I2C_M_RD) + memcpy(msg->buf, buf, msg->len); + + kfree(buf); +} +EXPORT_SYMBOL_GPL(i2c_put_dma_safe_msg_buf); + +MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); +MODULE_DESCRIPTION("I2C-Bus main module"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/i2c-core-of.c b/drivers/i2c/i2c-core-of.c new file mode 100644 index 000000000..a6c407d36 --- /dev/null +++ b/drivers/i2c/i2c-core-of.c @@ -0,0 +1,220 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Linux I2C core OF support code + * + * Copyright (C) 2008 Jochen Friedrich <jochen@scram.de> + * based on a previous patch from Jon Smirl <jonsmirl@gmail.com> + * + * Copyright (C) 2013, 2018 Wolfram Sang <wsa@kernel.org> + */ + +#include <dt-bindings/i2c/i2c.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/sysfs.h> + +#include "i2c-core.h" + +int of_i2c_get_board_info(struct device *dev, struct device_node *node, + struct i2c_board_info *info) +{ + u32 addr; + int ret; + + memset(info, 0, sizeof(*info)); + + if (of_alias_from_compatible(node, info->type, sizeof(info->type)) < 0) { + dev_err(dev, "of_i2c: modalias failure on %pOF\n", node); + return -EINVAL; + } + + ret = of_property_read_u32(node, "reg", &addr); + if (ret) { + dev_err(dev, "of_i2c: invalid reg on %pOF\n", node); + return ret; + } + + if (addr & I2C_TEN_BIT_ADDRESS) { + addr &= ~I2C_TEN_BIT_ADDRESS; + info->flags |= I2C_CLIENT_TEN; + } + + if (addr & I2C_OWN_SLAVE_ADDRESS) { + addr &= ~I2C_OWN_SLAVE_ADDRESS; + info->flags |= I2C_CLIENT_SLAVE; + } + + info->addr = addr; + info->of_node = node; + info->fwnode = of_fwnode_handle(node); + + if (of_property_read_bool(node, "host-notify")) + info->flags |= I2C_CLIENT_HOST_NOTIFY; + + if (of_property_read_bool(node, "wakeup-source")) + info->flags |= I2C_CLIENT_WAKE; + + return 0; +} +EXPORT_SYMBOL_GPL(of_i2c_get_board_info); + +static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap, + struct device_node *node) +{ + struct i2c_client *client; + struct i2c_board_info info; + int ret; + + dev_dbg(&adap->dev, "of_i2c: register %pOF\n", node); + + ret = of_i2c_get_board_info(&adap->dev, node, &info); + if (ret) + return ERR_PTR(ret); + + client = i2c_new_client_device(adap, &info); + if (IS_ERR(client)) + dev_err(&adap->dev, "of_i2c: Failure registering %pOF\n", node); + + return client; +} + +void of_i2c_register_devices(struct i2c_adapter *adap) +{ + struct device_node *bus, *node; + struct i2c_client *client; + + /* Only register child devices if the adapter has a node pointer set */ + if (!adap->dev.of_node) + return; + + dev_dbg(&adap->dev, "of_i2c: walking child nodes\n"); + + bus = of_get_child_by_name(adap->dev.of_node, "i2c-bus"); + if (!bus) + bus = of_node_get(adap->dev.of_node); + + for_each_available_child_of_node(bus, node) { + if (of_node_test_and_set_flag(node, OF_POPULATED)) + continue; + + client = of_i2c_register_device(adap, node); + if (IS_ERR(client)) { + dev_err(&adap->dev, + "Failed to create I2C device for %pOF\n", + node); + of_node_clear_flag(node, OF_POPULATED); + } + } + + of_node_put(bus); +} + +static const struct of_device_id* +i2c_of_match_device_sysfs(const struct of_device_id *matches, + struct i2c_client *client) +{ + const char *name; + + for (; matches->compatible[0]; matches++) { + /* + * Adding devices through the i2c sysfs interface provides us + * a string to match which may be compatible with the device + * tree compatible strings, however with no actual of_node the + * of_match_device() will not match + */ + if (sysfs_streq(client->name, matches->compatible)) + return matches; + + name = strchr(matches->compatible, ','); + if (!name) + name = matches->compatible; + else + name++; + + if (sysfs_streq(client->name, name)) + return matches; + } + + return NULL; +} + +const struct of_device_id +*i2c_of_match_device(const struct of_device_id *matches, + struct i2c_client *client) +{ + const struct of_device_id *match; + + if (!(client && matches)) + return NULL; + + match = of_match_device(matches, &client->dev); + if (match) + return match; + + return i2c_of_match_device_sysfs(matches, client); +} +EXPORT_SYMBOL_GPL(i2c_of_match_device); + +#if IS_ENABLED(CONFIG_OF_DYNAMIC) +static int of_i2c_notify(struct notifier_block *nb, unsigned long action, + void *arg) +{ + struct of_reconfig_data *rd = arg; + struct i2c_adapter *adap; + struct i2c_client *client; + + switch (of_reconfig_get_state_change(action, rd)) { + case OF_RECONFIG_CHANGE_ADD: + adap = of_find_i2c_adapter_by_node(rd->dn->parent); + if (adap == NULL) + return NOTIFY_OK; /* not for us */ + + if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) { + put_device(&adap->dev); + return NOTIFY_OK; + } + + /* + * Clear the flag before adding the device so that fw_devlink + * doesn't skip adding consumers to this device. + */ + rd->dn->fwnode.flags &= ~FWNODE_FLAG_NOT_DEVICE; + client = of_i2c_register_device(adap, rd->dn); + if (IS_ERR(client)) { + dev_err(&adap->dev, "failed to create client for '%pOF'\n", + rd->dn); + put_device(&adap->dev); + of_node_clear_flag(rd->dn, OF_POPULATED); + return notifier_from_errno(PTR_ERR(client)); + } + put_device(&adap->dev); + break; + case OF_RECONFIG_CHANGE_REMOVE: + /* already depopulated? */ + if (!of_node_check_flag(rd->dn, OF_POPULATED)) + return NOTIFY_OK; + + /* find our device by node */ + client = of_find_i2c_device_by_node(rd->dn); + if (client == NULL) + return NOTIFY_OK; /* no? not meant for us */ + + /* unregister takes one ref away */ + i2c_unregister_device(client); + + /* and put the reference of the find */ + put_device(&client->dev); + break; + } + + return NOTIFY_OK; +} + +struct notifier_block i2c_of_notifier = { + .notifier_call = of_i2c_notify, +}; +#endif /* CONFIG_OF_DYNAMIC */ diff --git a/drivers/i2c/i2c-core-slave.c b/drivers/i2c/i2c-core-slave.c new file mode 100644 index 000000000..e3765e12f --- /dev/null +++ b/drivers/i2c/i2c-core-slave.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Linux I2C core slave support code + * + * Copyright (C) 2014 by Wolfram Sang <wsa@sang-engineering.com> + */ + +#include <dt-bindings/i2c/i2c.h> +#include <linux/acpi.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/of.h> + +#include "i2c-core.h" + +#define CREATE_TRACE_POINTS +#include <trace/events/i2c_slave.h> + +int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb) +{ + int ret; + + if (WARN(IS_ERR_OR_NULL(client) || !slave_cb, "insufficient data\n")) + return -EINVAL; + + if (!(client->flags & I2C_CLIENT_SLAVE)) + dev_warn(&client->dev, "%s: client slave flag not set. You might see address collisions\n", + __func__); + + if (!(client->flags & I2C_CLIENT_TEN)) { + /* Enforce stricter address checking */ + ret = i2c_check_7bit_addr_validity_strict(client->addr); + if (ret) { + dev_err(&client->dev, "%s: invalid address\n", __func__); + return ret; + } + } + + if (!client->adapter->algo->reg_slave) { + dev_err(&client->dev, "%s: not supported by adapter\n", __func__); + return -EOPNOTSUPP; + } + + client->slave_cb = slave_cb; + + i2c_lock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER); + ret = client->adapter->algo->reg_slave(client); + i2c_unlock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER); + + if (ret) { + client->slave_cb = NULL; + dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret); + } + + return ret; +} +EXPORT_SYMBOL_GPL(i2c_slave_register); + +int i2c_slave_unregister(struct i2c_client *client) +{ + int ret; + + if (IS_ERR_OR_NULL(client)) + return -EINVAL; + + if (!client->adapter->algo->unreg_slave) { + dev_err(&client->dev, "%s: not supported by adapter\n", __func__); + return -EOPNOTSUPP; + } + + i2c_lock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER); + ret = client->adapter->algo->unreg_slave(client); + i2c_unlock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER); + + if (ret == 0) + client->slave_cb = NULL; + else + dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(i2c_slave_unregister); + +int i2c_slave_event(struct i2c_client *client, + enum i2c_slave_event event, u8 *val) +{ + int ret = client->slave_cb(client, event, val); + + if (trace_i2c_slave_enabled()) + trace_i2c_slave(client, event, val, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(i2c_slave_event); + +/** + * i2c_detect_slave_mode - detect operation mode + * @dev: The device owning the bus + * + * This checks the device nodes for an I2C slave by checking the address + * used in the reg property. If the address match the I2C_OWN_SLAVE_ADDRESS + * flag this means the device is configured to act as a I2C slave and it will + * be listening at that address. + * + * Returns true if an I2C own slave address is detected, otherwise returns + * false. + */ +bool i2c_detect_slave_mode(struct device *dev) +{ + if (IS_BUILTIN(CONFIG_OF) && dev->of_node) { + struct device_node *child; + u32 reg; + + for_each_child_of_node(dev->of_node, child) { + of_property_read_u32(child, "reg", ®); + if (reg & I2C_OWN_SLAVE_ADDRESS) { + of_node_put(child); + return true; + } + } + } else if (IS_BUILTIN(CONFIG_ACPI) && ACPI_HANDLE(dev)) { + dev_dbg(dev, "ACPI slave is not supported yet\n"); + } + return false; +} +EXPORT_SYMBOL_GPL(i2c_detect_slave_mode); diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c new file mode 100644 index 000000000..e3b96fc53 --- /dev/null +++ b/drivers/i2c/i2c-core-smbus.c @@ -0,0 +1,723 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Linux I2C core SMBus and SMBus emulation code + * + * This file contains the SMBus functions which are always included in the I2C + * core because they can be emulated via I2C. SMBus specific extensions + * (e.g. smbalert) are handled in a separate i2c-smbus module. + * + * All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl> + * SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and + * Jean Delvare <jdelvare@suse.de> + */ +#include <linux/device.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/i2c-smbus.h> +#include <linux/property.h> +#include <linux/slab.h> + +#include "i2c-core.h" + +#define CREATE_TRACE_POINTS +#include <trace/events/smbus.h> + + +/* The SMBus parts */ + +#define POLY (0x1070U << 3) +static u8 crc8(u16 data) +{ + int i; + + for (i = 0; i < 8; i++) { + if (data & 0x8000) + data = data ^ POLY; + data = data << 1; + } + return (u8)(data >> 8); +} + +/** + * i2c_smbus_pec - Incremental CRC8 over the given input data array + * @crc: previous return crc8 value + * @p: pointer to data buffer. + * @count: number of bytes in data buffer. + * + * Incremental CRC8 over count bytes in the array pointed to by p + */ +u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) +{ + int i; + + for (i = 0; i < count; i++) + crc = crc8((crc ^ p[i]) << 8); + return crc; +} +EXPORT_SYMBOL(i2c_smbus_pec); + +/* Assume a 7-bit address, which is reasonable for SMBus */ +static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) +{ + /* The address will be sent first */ + u8 addr = i2c_8bit_addr_from_msg(msg); + pec = i2c_smbus_pec(pec, &addr, 1); + + /* The data buffer follows */ + return i2c_smbus_pec(pec, msg->buf, msg->len); +} + +/* Used for write only transactions */ +static inline void i2c_smbus_add_pec(struct i2c_msg *msg) +{ + msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); + msg->len++; +} + +/* Return <0 on CRC error + If there was a write before this read (most cases) we need to take the + partial CRC from the write part into account. + Note that this function does modify the message (we need to decrease the + message length to hide the CRC byte from the caller). */ +static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) +{ + u8 rpec = msg->buf[--msg->len]; + cpec = i2c_smbus_msg_pec(cpec, msg); + + if (rpec != cpec) { + pr_debug("Bad PEC 0x%02x vs. 0x%02x\n", + rpec, cpec); + return -EBADMSG; + } + return 0; +} + +/** + * i2c_smbus_read_byte - SMBus "receive byte" protocol + * @client: Handle to slave device + * + * This executes the SMBus "receive byte" protocol, returning negative errno + * else the byte received from the device. + */ +s32 i2c_smbus_read_byte(const struct i2c_client *client) +{ + union i2c_smbus_data data; + int status; + + status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, + I2C_SMBUS_READ, 0, + I2C_SMBUS_BYTE, &data); + return (status < 0) ? status : data.byte; +} +EXPORT_SYMBOL(i2c_smbus_read_byte); + +/** + * i2c_smbus_write_byte - SMBus "send byte" protocol + * @client: Handle to slave device + * @value: Byte to be sent + * + * This executes the SMBus "send byte" protocol, returning negative errno + * else zero on success. + */ +s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value) +{ + return i2c_smbus_xfer(client->adapter, client->addr, client->flags, + I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); +} +EXPORT_SYMBOL(i2c_smbus_write_byte); + +/** + * i2c_smbus_read_byte_data - SMBus "read byte" protocol + * @client: Handle to slave device + * @command: Byte interpreted by slave + * + * This executes the SMBus "read byte" protocol, returning negative errno + * else a data byte received from the device. + */ +s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command) +{ + union i2c_smbus_data data; + int status; + + status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, + I2C_SMBUS_READ, command, + I2C_SMBUS_BYTE_DATA, &data); + return (status < 0) ? status : data.byte; +} +EXPORT_SYMBOL(i2c_smbus_read_byte_data); + +/** + * i2c_smbus_write_byte_data - SMBus "write byte" protocol + * @client: Handle to slave device + * @command: Byte interpreted by slave + * @value: Byte being written + * + * This executes the SMBus "write byte" protocol, returning negative errno + * else zero on success. + */ +s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command, + u8 value) +{ + union i2c_smbus_data data; + data.byte = value; + return i2c_smbus_xfer(client->adapter, client->addr, client->flags, + I2C_SMBUS_WRITE, command, + I2C_SMBUS_BYTE_DATA, &data); +} +EXPORT_SYMBOL(i2c_smbus_write_byte_data); + +/** + * i2c_smbus_read_word_data - SMBus "read word" protocol + * @client: Handle to slave device + * @command: Byte interpreted by slave + * + * This executes the SMBus "read word" protocol, returning negative errno + * else a 16-bit unsigned "word" received from the device. + */ +s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command) +{ + union i2c_smbus_data data; + int status; + + status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, + I2C_SMBUS_READ, command, + I2C_SMBUS_WORD_DATA, &data); + return (status < 0) ? status : data.word; +} +EXPORT_SYMBOL(i2c_smbus_read_word_data); + +/** + * i2c_smbus_write_word_data - SMBus "write word" protocol + * @client: Handle to slave device + * @command: Byte interpreted by slave + * @value: 16-bit "word" being written + * + * This executes the SMBus "write word" protocol, returning negative errno + * else zero on success. + */ +s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command, + u16 value) +{ + union i2c_smbus_data data; + data.word = value; + return i2c_smbus_xfer(client->adapter, client->addr, client->flags, + I2C_SMBUS_WRITE, command, + I2C_SMBUS_WORD_DATA, &data); +} +EXPORT_SYMBOL(i2c_smbus_write_word_data); + +/** + * i2c_smbus_read_block_data - SMBus "block read" protocol + * @client: Handle to slave device + * @command: Byte interpreted by slave + * @values: Byte array into which data will be read; big enough to hold + * the data returned by the slave. SMBus allows at most 32 bytes. + * + * This executes the SMBus "block read" protocol, returning negative errno + * else the number of data bytes in the slave's response. + * + * Note that using this function requires that the client's adapter support + * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality. Not all adapter drivers + * support this; its emulation through I2C messaging relies on a specific + * mechanism (I2C_M_RECV_LEN) which may not be implemented. + */ +s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, + u8 *values) +{ + union i2c_smbus_data data; + int status; + + status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, + I2C_SMBUS_READ, command, + I2C_SMBUS_BLOCK_DATA, &data); + if (status) + return status; + + memcpy(values, &data.block[1], data.block[0]); + return data.block[0]; +} +EXPORT_SYMBOL(i2c_smbus_read_block_data); + +/** + * i2c_smbus_write_block_data - SMBus "block write" protocol + * @client: Handle to slave device + * @command: Byte interpreted by slave + * @length: Size of data block; SMBus allows at most 32 bytes + * @values: Byte array which will be written. + * + * This executes the SMBus "block write" protocol, returning negative errno + * else zero on success. + */ +s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command, + u8 length, const u8 *values) +{ + union i2c_smbus_data data; + + if (length > I2C_SMBUS_BLOCK_MAX) + length = I2C_SMBUS_BLOCK_MAX; + data.block[0] = length; + memcpy(&data.block[1], values, length); + return i2c_smbus_xfer(client->adapter, client->addr, client->flags, + I2C_SMBUS_WRITE, command, + I2C_SMBUS_BLOCK_DATA, &data); +} +EXPORT_SYMBOL(i2c_smbus_write_block_data); + +/* Returns the number of read bytes */ +s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command, + u8 length, u8 *values) +{ + union i2c_smbus_data data; + int status; + + if (length > I2C_SMBUS_BLOCK_MAX) + length = I2C_SMBUS_BLOCK_MAX; + data.block[0] = length; + status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, + I2C_SMBUS_READ, command, + I2C_SMBUS_I2C_BLOCK_DATA, &data); + if (status < 0) + return status; + + memcpy(values, &data.block[1], data.block[0]); + return data.block[0]; +} +EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); + +s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command, + u8 length, const u8 *values) +{ + union i2c_smbus_data data; + + if (length > I2C_SMBUS_BLOCK_MAX) + length = I2C_SMBUS_BLOCK_MAX; + data.block[0] = length; + memcpy(data.block + 1, values, length); + return i2c_smbus_xfer(client->adapter, client->addr, client->flags, + I2C_SMBUS_WRITE, command, + I2C_SMBUS_I2C_BLOCK_DATA, &data); +} +EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data); + +static void i2c_smbus_try_get_dmabuf(struct i2c_msg *msg, u8 init_val) +{ + bool is_read = msg->flags & I2C_M_RD; + unsigned char *dma_buf; + + dma_buf = kzalloc(I2C_SMBUS_BLOCK_MAX + (is_read ? 2 : 3), GFP_KERNEL); + if (!dma_buf) + return; + + msg->buf = dma_buf; + msg->flags |= I2C_M_DMA_SAFE; + + if (init_val) + msg->buf[0] = init_val; +} + +/* + * Simulate a SMBus command using the I2C protocol. + * No checking of parameters is done! + */ +static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, + unsigned short flags, + char read_write, u8 command, int size, + union i2c_smbus_data *data) +{ + /* + * So we need to generate a series of msgs. In the case of writing, we + * need to use only one message; when reading, we need two. We + * initialize most things with sane defaults, to keep the code below + * somewhat simpler. + */ + unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; + unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; + int nmsgs = read_write == I2C_SMBUS_READ ? 2 : 1; + u8 partial_pec = 0; + int status; + struct i2c_msg msg[2] = { + { + .addr = addr, + .flags = flags, + .len = 1, + .buf = msgbuf0, + }, { + .addr = addr, + .flags = flags | I2C_M_RD, + .len = 0, + .buf = msgbuf1, + }, + }; + bool wants_pec = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK + && size != I2C_SMBUS_I2C_BLOCK_DATA); + + msgbuf0[0] = command; + switch (size) { + case I2C_SMBUS_QUICK: + msg[0].len = 0; + /* Special case: The read/write field is used as data */ + msg[0].flags = flags | (read_write == I2C_SMBUS_READ ? + I2C_M_RD : 0); + nmsgs = 1; + break; + case I2C_SMBUS_BYTE: + if (read_write == I2C_SMBUS_READ) { + /* Special case: only a read! */ + msg[0].flags = I2C_M_RD | flags; + nmsgs = 1; + } + break; + case I2C_SMBUS_BYTE_DATA: + if (read_write == I2C_SMBUS_READ) + msg[1].len = 1; + else { + msg[0].len = 2; + msgbuf0[1] = data->byte; + } + break; + case I2C_SMBUS_WORD_DATA: + if (read_write == I2C_SMBUS_READ) + msg[1].len = 2; + else { + msg[0].len = 3; + msgbuf0[1] = data->word & 0xff; + msgbuf0[2] = data->word >> 8; + } + break; + case I2C_SMBUS_PROC_CALL: + nmsgs = 2; /* Special case */ + read_write = I2C_SMBUS_READ; + msg[0].len = 3; + msg[1].len = 2; + msgbuf0[1] = data->word & 0xff; + msgbuf0[2] = data->word >> 8; + break; + case I2C_SMBUS_BLOCK_DATA: + if (read_write == I2C_SMBUS_READ) { + msg[1].flags |= I2C_M_RECV_LEN; + msg[1].len = 1; /* block length will be added by + the underlying bus driver */ + i2c_smbus_try_get_dmabuf(&msg[1], 0); + } else { + msg[0].len = data->block[0] + 2; + if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) { + dev_err(&adapter->dev, + "Invalid block write size %d\n", + data->block[0]); + return -EINVAL; + } + + i2c_smbus_try_get_dmabuf(&msg[0], command); + memcpy(msg[0].buf + 1, data->block, msg[0].len - 1); + } + break; + case I2C_SMBUS_BLOCK_PROC_CALL: + nmsgs = 2; /* Another special case */ + read_write = I2C_SMBUS_READ; + if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { + dev_err(&adapter->dev, + "Invalid block write size %d\n", + data->block[0]); + return -EINVAL; + } + + msg[0].len = data->block[0] + 2; + i2c_smbus_try_get_dmabuf(&msg[0], command); + memcpy(msg[0].buf + 1, data->block, msg[0].len - 1); + + msg[1].flags |= I2C_M_RECV_LEN; + msg[1].len = 1; /* block length will be added by + the underlying bus driver */ + i2c_smbus_try_get_dmabuf(&msg[1], 0); + break; + case I2C_SMBUS_I2C_BLOCK_DATA: + if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { + dev_err(&adapter->dev, "Invalid block %s size %d\n", + read_write == I2C_SMBUS_READ ? "read" : "write", + data->block[0]); + return -EINVAL; + } + + if (read_write == I2C_SMBUS_READ) { + msg[1].len = data->block[0]; + i2c_smbus_try_get_dmabuf(&msg[1], 0); + } else { + msg[0].len = data->block[0] + 1; + + i2c_smbus_try_get_dmabuf(&msg[0], command); + memcpy(msg[0].buf + 1, data->block + 1, data->block[0]); + } + break; + default: + dev_err(&adapter->dev, "Unsupported transaction %d\n", size); + return -EOPNOTSUPP; + } + + if (wants_pec) { + /* Compute PEC if first message is a write */ + if (!(msg[0].flags & I2C_M_RD)) { + if (nmsgs == 1) /* Write only */ + i2c_smbus_add_pec(&msg[0]); + else /* Write followed by read */ + partial_pec = i2c_smbus_msg_pec(0, &msg[0]); + } + /* Ask for PEC if last message is a read */ + if (msg[nmsgs - 1].flags & I2C_M_RD) + msg[nmsgs - 1].len++; + } + + status = __i2c_transfer(adapter, msg, nmsgs); + if (status < 0) + goto cleanup; + if (status != nmsgs) { + status = -EIO; + goto cleanup; + } + status = 0; + + /* Check PEC if last message is a read */ + if (wants_pec && (msg[nmsgs - 1].flags & I2C_M_RD)) { + status = i2c_smbus_check_pec(partial_pec, &msg[nmsgs - 1]); + if (status < 0) + goto cleanup; + } + + if (read_write == I2C_SMBUS_READ) + switch (size) { + case I2C_SMBUS_BYTE: + data->byte = msgbuf0[0]; + break; + case I2C_SMBUS_BYTE_DATA: + data->byte = msgbuf1[0]; + break; + case I2C_SMBUS_WORD_DATA: + case I2C_SMBUS_PROC_CALL: + data->word = msgbuf1[0] | (msgbuf1[1] << 8); + break; + case I2C_SMBUS_I2C_BLOCK_DATA: + memcpy(data->block + 1, msg[1].buf, data->block[0]); + break; + case I2C_SMBUS_BLOCK_DATA: + case I2C_SMBUS_BLOCK_PROC_CALL: + if (msg[1].buf[0] > I2C_SMBUS_BLOCK_MAX) { + dev_err(&adapter->dev, + "Invalid block size returned: %d\n", + msg[1].buf[0]); + status = -EPROTO; + goto cleanup; + } + memcpy(data->block, msg[1].buf, msg[1].buf[0] + 1); + break; + } + +cleanup: + if (msg[0].flags & I2C_M_DMA_SAFE) + kfree(msg[0].buf); + if (msg[1].flags & I2C_M_DMA_SAFE) + kfree(msg[1].buf); + + return status; +} + +/** + * i2c_smbus_xfer - execute SMBus protocol operations + * @adapter: Handle to I2C bus + * @addr: Address of SMBus slave on that bus + * @flags: I2C_CLIENT_* flags (usually zero or I2C_CLIENT_PEC) + * @read_write: I2C_SMBUS_READ or I2C_SMBUS_WRITE + * @command: Byte interpreted by slave, for protocols which use such bytes + * @protocol: SMBus protocol operation to execute, such as I2C_SMBUS_PROC_CALL + * @data: Data to be read or written + * + * This executes an SMBus protocol operation, and returns a negative + * errno code else zero on success. + */ +s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, + unsigned short flags, char read_write, + u8 command, int protocol, union i2c_smbus_data *data) +{ + s32 res; + + res = __i2c_lock_bus_helper(adapter); + if (res) + return res; + + res = __i2c_smbus_xfer(adapter, addr, flags, read_write, + command, protocol, data); + i2c_unlock_bus(adapter, I2C_LOCK_SEGMENT); + + return res; +} +EXPORT_SYMBOL(i2c_smbus_xfer); + +s32 __i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, + unsigned short flags, char read_write, + u8 command, int protocol, union i2c_smbus_data *data) +{ + int (*xfer_func)(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, union i2c_smbus_data *data); + unsigned long orig_jiffies; + int try; + s32 res; + + res = __i2c_check_suspended(adapter); + if (res) + return res; + + /* If enabled, the following two tracepoints are conditional on + * read_write and protocol. + */ + trace_smbus_write(adapter, addr, flags, read_write, + command, protocol, data); + trace_smbus_read(adapter, addr, flags, read_write, + command, protocol); + + flags &= I2C_M_TEN | I2C_CLIENT_PEC | I2C_CLIENT_SCCB; + + xfer_func = adapter->algo->smbus_xfer; + if (i2c_in_atomic_xfer_mode()) { + if (adapter->algo->smbus_xfer_atomic) + xfer_func = adapter->algo->smbus_xfer_atomic; + else if (adapter->algo->master_xfer_atomic) + xfer_func = NULL; /* fallback to I2C emulation */ + } + + if (xfer_func) { + /* Retry automatically on arbitration loss */ + orig_jiffies = jiffies; + for (res = 0, try = 0; try <= adapter->retries; try++) { + res = xfer_func(adapter, addr, flags, read_write, + command, protocol, data); + if (res != -EAGAIN) + break; + if (time_after(jiffies, + orig_jiffies + adapter->timeout)) + break; + } + + if (res != -EOPNOTSUPP || !adapter->algo->master_xfer) + goto trace; + /* + * Fall back to i2c_smbus_xfer_emulated if the adapter doesn't + * implement native support for the SMBus operation. + */ + } + + res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write, + command, protocol, data); + +trace: + /* If enabled, the reply tracepoint is conditional on read_write. */ + trace_smbus_reply(adapter, addr, flags, read_write, + command, protocol, data, res); + trace_smbus_result(adapter, addr, flags, read_write, + command, protocol, res); + + return res; +} +EXPORT_SYMBOL(__i2c_smbus_xfer); + +/** + * i2c_smbus_read_i2c_block_data_or_emulated - read block or emulate + * @client: Handle to slave device + * @command: Byte interpreted by slave + * @length: Size of data block; SMBus allows at most I2C_SMBUS_BLOCK_MAX bytes + * @values: Byte array into which data will be read; big enough to hold + * the data returned by the slave. SMBus allows at most + * I2C_SMBUS_BLOCK_MAX bytes. + * + * This executes the SMBus "block read" protocol if supported by the adapter. + * If block read is not supported, it emulates it using either word or byte + * read protocols depending on availability. + * + * The addresses of the I2C slave device that are accessed with this function + * must be mapped to a linear region, so that a block read will have the same + * effect as a byte read. Before using this function you must double-check + * if the I2C slave does support exchanging a block transfer with a byte + * transfer. + */ +s32 i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client, + u8 command, u8 length, u8 *values) +{ + u8 i = 0; + int status; + + if (length > I2C_SMBUS_BLOCK_MAX) + length = I2C_SMBUS_BLOCK_MAX; + + if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) + return i2c_smbus_read_i2c_block_data(client, command, length, values); + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA)) + return -EOPNOTSUPP; + + if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_WORD_DATA)) { + while ((i + 2) <= length) { + status = i2c_smbus_read_word_data(client, command + i); + if (status < 0) + return status; + values[i] = status & 0xff; + values[i + 1] = status >> 8; + i += 2; + } + } + + while (i < length) { + status = i2c_smbus_read_byte_data(client, command + i); + if (status < 0) + return status; + values[i] = status; + i++; + } + + return i; +} +EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data_or_emulated); + +/** + * i2c_new_smbus_alert_device - get ara client for SMBus alert support + * @adapter: the target adapter + * @setup: setup data for the SMBus alert handler + * Context: can sleep + * + * Setup handling of the SMBus alert protocol on a given I2C bus segment. + * + * Handling can be done either through our IRQ handler, or by the + * adapter (from its handler, periodic polling, or whatever). + * + * This returns the ara client, which should be saved for later use with + * i2c_handle_smbus_alert() and ultimately i2c_unregister_device(); or an + * ERRPTR to indicate an error. + */ +struct i2c_client *i2c_new_smbus_alert_device(struct i2c_adapter *adapter, + struct i2c_smbus_alert_setup *setup) +{ + struct i2c_board_info ara_board_info = { + I2C_BOARD_INFO("smbus_alert", 0x0c), + .platform_data = setup, + }; + + return i2c_new_client_device(adapter, &ara_board_info); +} +EXPORT_SYMBOL_GPL(i2c_new_smbus_alert_device); + +#if IS_ENABLED(CONFIG_I2C_SMBUS) +int i2c_setup_smbus_alert(struct i2c_adapter *adapter) +{ + struct device *parent = adapter->dev.parent; + int irq; + + /* Adapter instantiated without parent, skip the SMBus alert setup */ + if (!parent) + return 0; + + irq = device_property_match_string(parent, "interrupt-names", "smbus_alert"); + if (irq == -EINVAL || irq == -ENODATA) + return 0; + else if (irq < 0) + return irq; + + return PTR_ERR_OR_ZERO(i2c_new_smbus_alert_device(adapter, NULL)); +} +#endif diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h new file mode 100644 index 000000000..36587f38d --- /dev/null +++ b/drivers/i2c/i2c-core.h @@ -0,0 +1,99 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * i2c-core.h - interfaces internal to the I2C framework + */ + +#include <linux/kconfig.h> +#include <linux/rwsem.h> + +struct i2c_devinfo { + struct list_head list; + int busnum; + struct i2c_board_info board_info; +}; + +/* board_lock protects board_list and first_dynamic_bus_num. + * only i2c core components are allowed to use these symbols. + */ +extern struct rw_semaphore __i2c_board_lock; +extern struct list_head __i2c_board_list; +extern int __i2c_first_dynamic_bus_num; + +int i2c_check_7bit_addr_validity_strict(unsigned short addr); +int i2c_dev_irq_from_resources(const struct resource *resources, + unsigned int num_resources); + +/* + * We only allow atomic transfers for very late communication, e.g. to access a + * PMIC when powering down. Atomic transfers are a corner case and not for + * generic use! + */ +static inline bool i2c_in_atomic_xfer_mode(void) +{ + return system_state > SYSTEM_RUNNING && + (IS_ENABLED(CONFIG_PREEMPT_COUNT) ? !preemptible() : irqs_disabled()); +} + +static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap) +{ + int ret = 0; + + if (i2c_in_atomic_xfer_mode()) { + WARN(!adap->algo->master_xfer_atomic && !adap->algo->smbus_xfer_atomic, + "No atomic I2C transfer handler for '%s'\n", dev_name(&adap->dev)); + ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT) ? 0 : -EAGAIN; + } else { + i2c_lock_bus(adap, I2C_LOCK_SEGMENT); + } + + return ret; +} + +static inline int __i2c_check_suspended(struct i2c_adapter *adap) +{ + if (test_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags)) { + if (!test_and_set_bit(I2C_ALF_SUSPEND_REPORTED, &adap->locked_flags)) + dev_WARN(&adap->dev, "Transfer while suspended\n"); + return -ESHUTDOWN; + } + + return 0; +} + +#ifdef CONFIG_ACPI +void i2c_acpi_register_devices(struct i2c_adapter *adap); + +int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable); +#else /* CONFIG_ACPI */ +static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { } + +static inline int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable) +{ + return 0; +} +#endif /* CONFIG_ACPI */ +extern struct notifier_block i2c_acpi_notifier; + +#ifdef CONFIG_ACPI_I2C_OPREGION +int i2c_acpi_install_space_handler(struct i2c_adapter *adapter); +void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter); +#else /* CONFIG_ACPI_I2C_OPREGION */ +static inline int i2c_acpi_install_space_handler(struct i2c_adapter *adapter) { return 0; } +static inline void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) { } +#endif /* CONFIG_ACPI_I2C_OPREGION */ + +#ifdef CONFIG_OF +void of_i2c_register_devices(struct i2c_adapter *adap); +#else +static inline void of_i2c_register_devices(struct i2c_adapter *adap) { } +#endif +extern struct notifier_block i2c_of_notifier; + +#if IS_ENABLED(CONFIG_I2C_SMBUS) +int i2c_setup_smbus_alert(struct i2c_adapter *adap); +#else +static inline int i2c_setup_smbus_alert(struct i2c_adapter *adap) +{ + return 0; +} +#endif diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c new file mode 100644 index 000000000..7d337380a --- /dev/null +++ b/drivers/i2c/i2c-dev.c @@ -0,0 +1,794 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + i2c-dev.c - i2c-bus driver, char device interface + + Copyright (C) 1995-97 Simon G. Vogl + Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl> + Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com> + +*/ + +/* Note that this is a complete rewrite of Simon Vogl's i2c-dev module. + But I have used so much of his original code and ideas that it seems + only fair to recognize him as co-author -- Frodo */ + +/* The I2C_RDWR ioctl code is written by Kolja Waschk <waschk@telos.de> */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/cdev.h> +#include <linux/compat.h> +#include <linux/device.h> +#include <linux/fs.h> +#include <linux/i2c-dev.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/jiffies.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/notifier.h> +#include <linux/slab.h> +#include <linux/uaccess.h> + +/* + * An i2c_dev represents an i2c_adapter ... an I2C or SMBus master, not a + * slave (i2c_client) with which messages will be exchanged. It's coupled + * with a character special file which is accessed by user mode drivers. + * + * The list of i2c_dev structures is parallel to the i2c_adapter lists + * maintained by the driver model, and is updated using bus notifications. + */ +struct i2c_dev { + struct list_head list; + struct i2c_adapter *adap; + struct device dev; + struct cdev cdev; +}; + +#define I2C_MINORS (MINORMASK + 1) +static LIST_HEAD(i2c_dev_list); +static DEFINE_SPINLOCK(i2c_dev_list_lock); + +static struct i2c_dev *i2c_dev_get_by_minor(unsigned index) +{ + struct i2c_dev *i2c_dev; + + spin_lock(&i2c_dev_list_lock); + list_for_each_entry(i2c_dev, &i2c_dev_list, list) { + if (i2c_dev->adap->nr == index) + goto found; + } + i2c_dev = NULL; +found: + spin_unlock(&i2c_dev_list_lock); + return i2c_dev; +} + +static struct i2c_dev *get_free_i2c_dev(struct i2c_adapter *adap) +{ + struct i2c_dev *i2c_dev; + + if (adap->nr >= I2C_MINORS) { + pr_err("Out of device minors (%d)\n", adap->nr); + return ERR_PTR(-ENODEV); + } + + i2c_dev = kzalloc(sizeof(*i2c_dev), GFP_KERNEL); + if (!i2c_dev) + return ERR_PTR(-ENOMEM); + i2c_dev->adap = adap; + + spin_lock(&i2c_dev_list_lock); + list_add_tail(&i2c_dev->list, &i2c_dev_list); + spin_unlock(&i2c_dev_list_lock); + return i2c_dev; +} + +static void put_i2c_dev(struct i2c_dev *i2c_dev, bool del_cdev) +{ + spin_lock(&i2c_dev_list_lock); + list_del(&i2c_dev->list); + spin_unlock(&i2c_dev_list_lock); + if (del_cdev) + cdev_device_del(&i2c_dev->cdev, &i2c_dev->dev); + put_device(&i2c_dev->dev); +} + +static ssize_t name_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct i2c_dev *i2c_dev = i2c_dev_get_by_minor(MINOR(dev->devt)); + + if (!i2c_dev) + return -ENODEV; + return sysfs_emit(buf, "%s\n", i2c_dev->adap->name); +} +static DEVICE_ATTR_RO(name); + +static struct attribute *i2c_attrs[] = { + &dev_attr_name.attr, + NULL, +}; +ATTRIBUTE_GROUPS(i2c); + +/* ------------------------------------------------------------------------- */ + +/* + * After opening an instance of this character special file, a file + * descriptor starts out associated only with an i2c_adapter (and bus). + * + * Using the I2C_RDWR ioctl(), you can then *immediately* issue i2c_msg + * traffic to any devices on the bus used by that adapter. That's because + * the i2c_msg vectors embed all the addressing information they need, and + * are submitted directly to an i2c_adapter. However, SMBus-only adapters + * don't support that interface. + * + * To use read()/write() system calls on that file descriptor, or to use + * SMBus interfaces (and work with SMBus-only hosts!), you must first issue + * an I2C_SLAVE (or I2C_SLAVE_FORCE) ioctl. That configures an anonymous + * (never registered) i2c_client so it holds the addressing information + * needed by those system calls and by this SMBus interface. + */ + +static ssize_t i2cdev_read(struct file *file, char __user *buf, size_t count, + loff_t *offset) +{ + char *tmp; + int ret; + + struct i2c_client *client = file->private_data; + + if (count > 8192) + count = 8192; + + tmp = kzalloc(count, GFP_KERNEL); + if (tmp == NULL) + return -ENOMEM; + + pr_debug("i2c-%d reading %zu bytes.\n", iminor(file_inode(file)), count); + + ret = i2c_master_recv(client, tmp, count); + if (ret >= 0) + if (copy_to_user(buf, tmp, ret)) + ret = -EFAULT; + kfree(tmp); + return ret; +} + +static ssize_t i2cdev_write(struct file *file, const char __user *buf, + size_t count, loff_t *offset) +{ + int ret; + char *tmp; + struct i2c_client *client = file->private_data; + + if (count > 8192) + count = 8192; + + tmp = memdup_user(buf, count); + if (IS_ERR(tmp)) + return PTR_ERR(tmp); + + pr_debug("i2c-%d writing %zu bytes.\n", iminor(file_inode(file)), count); + + ret = i2c_master_send(client, tmp, count); + kfree(tmp); + return ret; +} + +static int i2cdev_check(struct device *dev, void *addrp) +{ + struct i2c_client *client = i2c_verify_client(dev); + + if (!client || client->addr != *(unsigned int *)addrp) + return 0; + + return dev->driver ? -EBUSY : 0; +} + +/* walk up mux tree */ +static int i2cdev_check_mux_parents(struct i2c_adapter *adapter, int addr) +{ + struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); + int result; + + result = device_for_each_child(&adapter->dev, &addr, i2cdev_check); + if (!result && parent) + result = i2cdev_check_mux_parents(parent, addr); + + return result; +} + +/* recurse down mux tree */ +static int i2cdev_check_mux_children(struct device *dev, void *addrp) +{ + int result; + + if (dev->type == &i2c_adapter_type) + result = device_for_each_child(dev, addrp, + i2cdev_check_mux_children); + else + result = i2cdev_check(dev, addrp); + + return result; +} + +/* This address checking function differs from the one in i2c-core + in that it considers an address with a registered device, but no + driver bound to it, as NOT busy. */ +static int i2cdev_check_addr(struct i2c_adapter *adapter, unsigned int addr) +{ + struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); + int result = 0; + + if (parent) + result = i2cdev_check_mux_parents(parent, addr); + + if (!result) + result = device_for_each_child(&adapter->dev, &addr, + i2cdev_check_mux_children); + + return result; +} + +static noinline int i2cdev_ioctl_rdwr(struct i2c_client *client, + unsigned nmsgs, struct i2c_msg *msgs) +{ + u8 __user **data_ptrs; + int i, res; + + data_ptrs = kmalloc_array(nmsgs, sizeof(u8 __user *), GFP_KERNEL); + if (data_ptrs == NULL) { + kfree(msgs); + return -ENOMEM; + } + + res = 0; + for (i = 0; i < nmsgs; i++) { + /* Limit the size of the message to a sane amount */ + if (msgs[i].len > 8192) { + res = -EINVAL; + break; + } + + data_ptrs[i] = (u8 __user *)msgs[i].buf; + msgs[i].buf = memdup_user(data_ptrs[i], msgs[i].len); + if (IS_ERR(msgs[i].buf)) { + res = PTR_ERR(msgs[i].buf); + break; + } + /* memdup_user allocates with GFP_KERNEL, so DMA is ok */ + msgs[i].flags |= I2C_M_DMA_SAFE; + + /* + * If the message length is received from the slave (similar + * to SMBus block read), we must ensure that the buffer will + * be large enough to cope with a message length of + * I2C_SMBUS_BLOCK_MAX as this is the maximum underlying bus + * drivers allow. The first byte in the buffer must be + * pre-filled with the number of extra bytes, which must be + * at least one to hold the message length, but can be + * greater (for example to account for a checksum byte at + * the end of the message.) + */ + if (msgs[i].flags & I2C_M_RECV_LEN) { + if (!(msgs[i].flags & I2C_M_RD) || + msgs[i].len < 1 || msgs[i].buf[0] < 1 || + msgs[i].len < msgs[i].buf[0] + + I2C_SMBUS_BLOCK_MAX) { + i++; + res = -EINVAL; + break; + } + + msgs[i].len = msgs[i].buf[0]; + } + } + if (res < 0) { + int j; + for (j = 0; j < i; ++j) + kfree(msgs[j].buf); + kfree(data_ptrs); + kfree(msgs); + return res; + } + + res = i2c_transfer(client->adapter, msgs, nmsgs); + while (i-- > 0) { + if (res >= 0 && (msgs[i].flags & I2C_M_RD)) { + if (copy_to_user(data_ptrs[i], msgs[i].buf, + msgs[i].len)) + res = -EFAULT; + } + kfree(msgs[i].buf); + } + kfree(data_ptrs); + kfree(msgs); + return res; +} + +static noinline int i2cdev_ioctl_smbus(struct i2c_client *client, + u8 read_write, u8 command, u32 size, + union i2c_smbus_data __user *data) +{ + union i2c_smbus_data temp = {}; + int datasize, res; + + if ((size != I2C_SMBUS_BYTE) && + (size != I2C_SMBUS_QUICK) && + (size != I2C_SMBUS_BYTE_DATA) && + (size != I2C_SMBUS_WORD_DATA) && + (size != I2C_SMBUS_PROC_CALL) && + (size != I2C_SMBUS_BLOCK_DATA) && + (size != I2C_SMBUS_I2C_BLOCK_BROKEN) && + (size != I2C_SMBUS_I2C_BLOCK_DATA) && + (size != I2C_SMBUS_BLOCK_PROC_CALL)) { + dev_dbg(&client->adapter->dev, + "size out of range (%x) in ioctl I2C_SMBUS.\n", + size); + return -EINVAL; + } + /* Note that I2C_SMBUS_READ and I2C_SMBUS_WRITE are 0 and 1, + so the check is valid if size==I2C_SMBUS_QUICK too. */ + if ((read_write != I2C_SMBUS_READ) && + (read_write != I2C_SMBUS_WRITE)) { + dev_dbg(&client->adapter->dev, + "read_write out of range (%x) in ioctl I2C_SMBUS.\n", + read_write); + return -EINVAL; + } + + /* Note that command values are always valid! */ + + if ((size == I2C_SMBUS_QUICK) || + ((size == I2C_SMBUS_BYTE) && + (read_write == I2C_SMBUS_WRITE))) + /* These are special: we do not use data */ + return i2c_smbus_xfer(client->adapter, client->addr, + client->flags, read_write, + command, size, NULL); + + if (data == NULL) { + dev_dbg(&client->adapter->dev, + "data is NULL pointer in ioctl I2C_SMBUS.\n"); + return -EINVAL; + } + + if ((size == I2C_SMBUS_BYTE_DATA) || + (size == I2C_SMBUS_BYTE)) + datasize = sizeof(data->byte); + else if ((size == I2C_SMBUS_WORD_DATA) || + (size == I2C_SMBUS_PROC_CALL)) + datasize = sizeof(data->word); + else /* size == smbus block, i2c block, or block proc. call */ + datasize = sizeof(data->block); + + if ((size == I2C_SMBUS_PROC_CALL) || + (size == I2C_SMBUS_BLOCK_PROC_CALL) || + (size == I2C_SMBUS_I2C_BLOCK_DATA) || + (read_write == I2C_SMBUS_WRITE)) { + if (copy_from_user(&temp, data, datasize)) + return -EFAULT; + } + if (size == I2C_SMBUS_I2C_BLOCK_BROKEN) { + /* Convert old I2C block commands to the new + convention. This preserves binary compatibility. */ + size = I2C_SMBUS_I2C_BLOCK_DATA; + if (read_write == I2C_SMBUS_READ) + temp.block[0] = I2C_SMBUS_BLOCK_MAX; + } + res = i2c_smbus_xfer(client->adapter, client->addr, client->flags, + read_write, command, size, &temp); + if (!res && ((size == I2C_SMBUS_PROC_CALL) || + (size == I2C_SMBUS_BLOCK_PROC_CALL) || + (read_write == I2C_SMBUS_READ))) { + if (copy_to_user(data, &temp, datasize)) + return -EFAULT; + } + return res; +} + +static long i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + struct i2c_client *client = file->private_data; + unsigned long funcs; + + dev_dbg(&client->adapter->dev, "ioctl, cmd=0x%02x, arg=0x%02lx\n", + cmd, arg); + + switch (cmd) { + case I2C_SLAVE: + case I2C_SLAVE_FORCE: + if ((arg > 0x3ff) || + (((client->flags & I2C_M_TEN) == 0) && arg > 0x7f)) + return -EINVAL; + if (cmd == I2C_SLAVE && i2cdev_check_addr(client->adapter, arg)) + return -EBUSY; + /* REVISIT: address could become busy later */ + client->addr = arg; + return 0; + case I2C_TENBIT: + if (arg) + client->flags |= I2C_M_TEN; + else + client->flags &= ~I2C_M_TEN; + return 0; + case I2C_PEC: + /* + * Setting the PEC flag here won't affect kernel drivers, + * which will be using the i2c_client node registered with + * the driver model core. Likewise, when that client has + * the PEC flag already set, the i2c-dev driver won't see + * (or use) this setting. + */ + if (arg) + client->flags |= I2C_CLIENT_PEC; + else + client->flags &= ~I2C_CLIENT_PEC; + return 0; + case I2C_FUNCS: + funcs = i2c_get_functionality(client->adapter); + return put_user(funcs, (unsigned long __user *)arg); + + case I2C_RDWR: { + struct i2c_rdwr_ioctl_data rdwr_arg; + struct i2c_msg *rdwr_pa; + + if (copy_from_user(&rdwr_arg, + (struct i2c_rdwr_ioctl_data __user *)arg, + sizeof(rdwr_arg))) + return -EFAULT; + + if (!rdwr_arg.msgs || rdwr_arg.nmsgs == 0) + return -EINVAL; + + /* + * Put an arbitrary limit on the number of messages that can + * be sent at once + */ + if (rdwr_arg.nmsgs > I2C_RDWR_IOCTL_MAX_MSGS) + return -EINVAL; + + rdwr_pa = memdup_array_user(rdwr_arg.msgs, + rdwr_arg.nmsgs, sizeof(struct i2c_msg)); + if (IS_ERR(rdwr_pa)) + return PTR_ERR(rdwr_pa); + + return i2cdev_ioctl_rdwr(client, rdwr_arg.nmsgs, rdwr_pa); + } + + case I2C_SMBUS: { + struct i2c_smbus_ioctl_data data_arg; + if (copy_from_user(&data_arg, + (struct i2c_smbus_ioctl_data __user *) arg, + sizeof(struct i2c_smbus_ioctl_data))) + return -EFAULT; + return i2cdev_ioctl_smbus(client, data_arg.read_write, + data_arg.command, + data_arg.size, + data_arg.data); + } + case I2C_RETRIES: + if (arg > INT_MAX) + return -EINVAL; + + client->adapter->retries = arg; + break; + case I2C_TIMEOUT: + if (arg > INT_MAX) + return -EINVAL; + + /* For historical reasons, user-space sets the timeout + * value in units of 10 ms. + */ + client->adapter->timeout = msecs_to_jiffies(arg * 10); + break; + default: + /* NOTE: returning a fault code here could cause trouble + * in buggy userspace code. Some old kernel bugs returned + * zero in this case, and userspace code might accidentally + * have depended on that bug. + */ + return -ENOTTY; + } + return 0; +} + +#ifdef CONFIG_COMPAT + +struct i2c_smbus_ioctl_data32 { + u8 read_write; + u8 command; + u32 size; + compat_caddr_t data; /* union i2c_smbus_data *data */ +}; + +struct i2c_msg32 { + u16 addr; + u16 flags; + u16 len; + compat_caddr_t buf; +}; + +struct i2c_rdwr_ioctl_data32 { + compat_caddr_t msgs; /* struct i2c_msg __user *msgs */ + u32 nmsgs; +}; + +static long compat_i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + struct i2c_client *client = file->private_data; + unsigned long funcs; + switch (cmd) { + case I2C_FUNCS: + funcs = i2c_get_functionality(client->adapter); + return put_user(funcs, (compat_ulong_t __user *)arg); + case I2C_RDWR: { + struct i2c_rdwr_ioctl_data32 rdwr_arg; + struct i2c_msg32 __user *p; + struct i2c_msg *rdwr_pa; + int i; + + if (copy_from_user(&rdwr_arg, + (struct i2c_rdwr_ioctl_data32 __user *)arg, + sizeof(rdwr_arg))) + return -EFAULT; + + if (!rdwr_arg.msgs || rdwr_arg.nmsgs == 0) + return -EINVAL; + + if (rdwr_arg.nmsgs > I2C_RDWR_IOCTL_MAX_MSGS) + return -EINVAL; + + rdwr_pa = kmalloc_array(rdwr_arg.nmsgs, sizeof(struct i2c_msg), + GFP_KERNEL); + if (!rdwr_pa) + return -ENOMEM; + + p = compat_ptr(rdwr_arg.msgs); + for (i = 0; i < rdwr_arg.nmsgs; i++) { + struct i2c_msg32 umsg; + if (copy_from_user(&umsg, p + i, sizeof(umsg))) { + kfree(rdwr_pa); + return -EFAULT; + } + rdwr_pa[i] = (struct i2c_msg) { + .addr = umsg.addr, + .flags = umsg.flags, + .len = umsg.len, + .buf = (__force __u8 *)compat_ptr(umsg.buf), + }; + } + + return i2cdev_ioctl_rdwr(client, rdwr_arg.nmsgs, rdwr_pa); + } + case I2C_SMBUS: { + struct i2c_smbus_ioctl_data32 data32; + if (copy_from_user(&data32, + (void __user *) arg, + sizeof(data32))) + return -EFAULT; + return i2cdev_ioctl_smbus(client, data32.read_write, + data32.command, + data32.size, + compat_ptr(data32.data)); + } + default: + return i2cdev_ioctl(file, cmd, arg); + } +} +#else +#define compat_i2cdev_ioctl NULL +#endif + +static int i2cdev_open(struct inode *inode, struct file *file) +{ + unsigned int minor = iminor(inode); + struct i2c_client *client; + struct i2c_adapter *adap; + + adap = i2c_get_adapter(minor); + if (!adap) + return -ENODEV; + + /* This creates an anonymous i2c_client, which may later be + * pointed to some address using I2C_SLAVE or I2C_SLAVE_FORCE. + * + * This client is ** NEVER REGISTERED ** with the driver model + * or I2C core code!! It just holds private copies of addressing + * information and maybe a PEC flag. + */ + client = kzalloc(sizeof(*client), GFP_KERNEL); + if (!client) { + i2c_put_adapter(adap); + return -ENOMEM; + } + snprintf(client->name, I2C_NAME_SIZE, "i2c-dev %d", adap->nr); + + client->adapter = adap; + file->private_data = client; + + return 0; +} + +static int i2cdev_release(struct inode *inode, struct file *file) +{ + struct i2c_client *client = file->private_data; + + i2c_put_adapter(client->adapter); + kfree(client); + file->private_data = NULL; + + return 0; +} + +static const struct file_operations i2cdev_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .read = i2cdev_read, + .write = i2cdev_write, + .unlocked_ioctl = i2cdev_ioctl, + .compat_ioctl = compat_i2cdev_ioctl, + .open = i2cdev_open, + .release = i2cdev_release, +}; + +/* ------------------------------------------------------------------------- */ + +static struct class *i2c_dev_class; + +static void i2cdev_dev_release(struct device *dev) +{ + struct i2c_dev *i2c_dev; + + i2c_dev = container_of(dev, struct i2c_dev, dev); + kfree(i2c_dev); +} + +static int i2cdev_attach_adapter(struct device *dev) +{ + struct i2c_adapter *adap; + struct i2c_dev *i2c_dev; + int res; + + if (dev->type != &i2c_adapter_type) + return NOTIFY_DONE; + adap = to_i2c_adapter(dev); + + i2c_dev = get_free_i2c_dev(adap); + if (IS_ERR(i2c_dev)) + return NOTIFY_DONE; + + cdev_init(&i2c_dev->cdev, &i2cdev_fops); + i2c_dev->cdev.owner = THIS_MODULE; + + device_initialize(&i2c_dev->dev); + i2c_dev->dev.devt = MKDEV(I2C_MAJOR, adap->nr); + i2c_dev->dev.class = i2c_dev_class; + i2c_dev->dev.parent = &adap->dev; + i2c_dev->dev.release = i2cdev_dev_release; + + res = dev_set_name(&i2c_dev->dev, "i2c-%d", adap->nr); + if (res) + goto err_put_i2c_dev; + + res = cdev_device_add(&i2c_dev->cdev, &i2c_dev->dev); + if (res) + goto err_put_i2c_dev; + + pr_debug("adapter [%s] registered as minor %d\n", adap->name, adap->nr); + return NOTIFY_OK; + +err_put_i2c_dev: + put_i2c_dev(i2c_dev, false); + return NOTIFY_DONE; +} + +static int i2cdev_detach_adapter(struct device *dev) +{ + struct i2c_adapter *adap; + struct i2c_dev *i2c_dev; + + if (dev->type != &i2c_adapter_type) + return NOTIFY_DONE; + adap = to_i2c_adapter(dev); + + i2c_dev = i2c_dev_get_by_minor(adap->nr); + if (!i2c_dev) /* attach_adapter must have failed */ + return NOTIFY_DONE; + + put_i2c_dev(i2c_dev, true); + + pr_debug("adapter [%s] unregistered\n", adap->name); + return NOTIFY_OK; +} + +static int i2cdev_notifier_call(struct notifier_block *nb, unsigned long action, + void *data) +{ + struct device *dev = data; + + switch (action) { + case BUS_NOTIFY_ADD_DEVICE: + return i2cdev_attach_adapter(dev); + case BUS_NOTIFY_DEL_DEVICE: + return i2cdev_detach_adapter(dev); + } + + return NOTIFY_DONE; +} + +static struct notifier_block i2cdev_notifier = { + .notifier_call = i2cdev_notifier_call, +}; + +/* ------------------------------------------------------------------------- */ + +static int __init i2c_dev_attach_adapter(struct device *dev, void *dummy) +{ + i2cdev_attach_adapter(dev); + return 0; +} + +static int __exit i2c_dev_detach_adapter(struct device *dev, void *dummy) +{ + i2cdev_detach_adapter(dev); + return 0; +} + +/* + * module load/unload record keeping + */ + +static int __init i2c_dev_init(void) +{ + int res; + + pr_info("i2c /dev entries driver\n"); + + res = register_chrdev_region(MKDEV(I2C_MAJOR, 0), I2C_MINORS, "i2c"); + if (res) + goto out; + + i2c_dev_class = class_create("i2c-dev"); + if (IS_ERR(i2c_dev_class)) { + res = PTR_ERR(i2c_dev_class); + goto out_unreg_chrdev; + } + i2c_dev_class->dev_groups = i2c_groups; + + /* Keep track of adapters which will be added or removed later */ + res = bus_register_notifier(&i2c_bus_type, &i2cdev_notifier); + if (res) + goto out_unreg_class; + + /* Bind to already existing adapters right away */ + i2c_for_each_dev(NULL, i2c_dev_attach_adapter); + + return 0; + +out_unreg_class: + class_destroy(i2c_dev_class); +out_unreg_chrdev: + unregister_chrdev_region(MKDEV(I2C_MAJOR, 0), I2C_MINORS); +out: + pr_err("Driver Initialisation failed\n"); + return res; +} + +static void __exit i2c_dev_exit(void) +{ + bus_unregister_notifier(&i2c_bus_type, &i2cdev_notifier); + i2c_for_each_dev(NULL, i2c_dev_detach_adapter); + class_destroy(i2c_dev_class); + unregister_chrdev_region(MKDEV(I2C_MAJOR, 0), I2C_MINORS); +} + +MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>"); +MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); +MODULE_DESCRIPTION("I2C /dev entries driver"); +MODULE_LICENSE("GPL"); + +module_init(i2c_dev_init); +module_exit(i2c_dev_exit); diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c new file mode 100644 index 000000000..57ff09f18 --- /dev/null +++ b/drivers/i2c/i2c-mux.c @@ -0,0 +1,466 @@ +/* + * Multiplexed I2C bus driver. + * + * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it> + * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it> + * Copyright (c) 2009-2010 NSN GmbH & Co KG <michael.lawnick.ext@nsn.com> + * + * Simplifies access to complex multiplexed I2C bus topologies, by presenting + * each multiplexed bus segment as an additional I2C adapter. + * Supports multi-level mux'ing (mux behind a mux). + * + * Based on: + * i2c-virt.c from Kumar Gala <galak@kernel.crashing.org> + * i2c-virtual.c from Ken Harrenstien, Copyright (c) 2004 Google, Inc. + * i2c-virtual.c from Brian Kuschak <bkuschak@yahoo.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/acpi.h> +#include <linux/i2c.h> +#include <linux/i2c-mux.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/slab.h> +#include <linux/sysfs.h> + +/* multiplexer per channel data */ +struct i2c_mux_priv { + struct i2c_adapter adap; + struct i2c_algorithm algo; + struct i2c_mux_core *muxc; + u32 chan_id; +}; + +static int __i2c_mux_master_xfer(struct i2c_adapter *adap, + struct i2c_msg msgs[], int num) +{ + struct i2c_mux_priv *priv = adap->algo_data; + struct i2c_mux_core *muxc = priv->muxc; + struct i2c_adapter *parent = muxc->parent; + int ret; + + /* Switch to the right mux port and perform the transfer. */ + + ret = muxc->select(muxc, priv->chan_id); + if (ret >= 0) + ret = __i2c_transfer(parent, msgs, num); + if (muxc->deselect) + muxc->deselect(muxc, priv->chan_id); + + return ret; +} + +static int i2c_mux_master_xfer(struct i2c_adapter *adap, + struct i2c_msg msgs[], int num) +{ + struct i2c_mux_priv *priv = adap->algo_data; + struct i2c_mux_core *muxc = priv->muxc; + struct i2c_adapter *parent = muxc->parent; + int ret; + + /* Switch to the right mux port and perform the transfer. */ + + ret = muxc->select(muxc, priv->chan_id); + if (ret >= 0) + ret = i2c_transfer(parent, msgs, num); + if (muxc->deselect) + muxc->deselect(muxc, priv->chan_id); + + return ret; +} + +static int __i2c_mux_smbus_xfer(struct i2c_adapter *adap, + u16 addr, unsigned short flags, + char read_write, u8 command, + int size, union i2c_smbus_data *data) +{ + struct i2c_mux_priv *priv = adap->algo_data; + struct i2c_mux_core *muxc = priv->muxc; + struct i2c_adapter *parent = muxc->parent; + int ret; + + /* Select the right mux port and perform the transfer. */ + + ret = muxc->select(muxc, priv->chan_id); + if (ret >= 0) + ret = __i2c_smbus_xfer(parent, addr, flags, + read_write, command, size, data); + if (muxc->deselect) + muxc->deselect(muxc, priv->chan_id); + + return ret; +} + +static int i2c_mux_smbus_xfer(struct i2c_adapter *adap, + u16 addr, unsigned short flags, + char read_write, u8 command, + int size, union i2c_smbus_data *data) +{ + struct i2c_mux_priv *priv = adap->algo_data; + struct i2c_mux_core *muxc = priv->muxc; + struct i2c_adapter *parent = muxc->parent; + int ret; + + /* Select the right mux port and perform the transfer. */ + + ret = muxc->select(muxc, priv->chan_id); + if (ret >= 0) + ret = i2c_smbus_xfer(parent, addr, flags, + read_write, command, size, data); + if (muxc->deselect) + muxc->deselect(muxc, priv->chan_id); + + return ret; +} + +/* Return the parent's functionality */ +static u32 i2c_mux_functionality(struct i2c_adapter *adap) +{ + struct i2c_mux_priv *priv = adap->algo_data; + struct i2c_adapter *parent = priv->muxc->parent; + + return parent->algo->functionality(parent); +} + +/* Return all parent classes, merged */ +static unsigned int i2c_mux_parent_classes(struct i2c_adapter *parent) +{ + unsigned int class = 0; + + do { + class |= parent->class; + parent = i2c_parent_is_i2c_adapter(parent); + } while (parent); + + return class; +} + +static void i2c_mux_lock_bus(struct i2c_adapter *adapter, unsigned int flags) +{ + struct i2c_mux_priv *priv = adapter->algo_data; + struct i2c_adapter *parent = priv->muxc->parent; + + rt_mutex_lock_nested(&parent->mux_lock, i2c_adapter_depth(adapter)); + if (!(flags & I2C_LOCK_ROOT_ADAPTER)) + return; + i2c_lock_bus(parent, flags); +} + +static int i2c_mux_trylock_bus(struct i2c_adapter *adapter, unsigned int flags) +{ + struct i2c_mux_priv *priv = adapter->algo_data; + struct i2c_adapter *parent = priv->muxc->parent; + + if (!rt_mutex_trylock(&parent->mux_lock)) + return 0; /* mux_lock not locked, failure */ + if (!(flags & I2C_LOCK_ROOT_ADAPTER)) + return 1; /* we only want mux_lock, success */ + if (i2c_trylock_bus(parent, flags)) + return 1; /* parent locked too, success */ + rt_mutex_unlock(&parent->mux_lock); + return 0; /* parent not locked, failure */ +} + +static void i2c_mux_unlock_bus(struct i2c_adapter *adapter, unsigned int flags) +{ + struct i2c_mux_priv *priv = adapter->algo_data; + struct i2c_adapter *parent = priv->muxc->parent; + + if (flags & I2C_LOCK_ROOT_ADAPTER) + i2c_unlock_bus(parent, flags); + rt_mutex_unlock(&parent->mux_lock); +} + +static void i2c_parent_lock_bus(struct i2c_adapter *adapter, + unsigned int flags) +{ + struct i2c_mux_priv *priv = adapter->algo_data; + struct i2c_adapter *parent = priv->muxc->parent; + + rt_mutex_lock_nested(&parent->mux_lock, i2c_adapter_depth(adapter)); + i2c_lock_bus(parent, flags); +} + +static int i2c_parent_trylock_bus(struct i2c_adapter *adapter, + unsigned int flags) +{ + struct i2c_mux_priv *priv = adapter->algo_data; + struct i2c_adapter *parent = priv->muxc->parent; + + if (!rt_mutex_trylock(&parent->mux_lock)) + return 0; /* mux_lock not locked, failure */ + if (i2c_trylock_bus(parent, flags)) + return 1; /* parent locked too, success */ + rt_mutex_unlock(&parent->mux_lock); + return 0; /* parent not locked, failure */ +} + +static void i2c_parent_unlock_bus(struct i2c_adapter *adapter, + unsigned int flags) +{ + struct i2c_mux_priv *priv = adapter->algo_data; + struct i2c_adapter *parent = priv->muxc->parent; + + i2c_unlock_bus(parent, flags); + rt_mutex_unlock(&parent->mux_lock); +} + +struct i2c_adapter *i2c_root_adapter(struct device *dev) +{ + struct device *i2c; + struct i2c_adapter *i2c_root; + + /* + * Walk up the device tree to find an i2c adapter, indicating + * that this is an i2c client device. Check all ancestors to + * handle mfd devices etc. + */ + for (i2c = dev; i2c; i2c = i2c->parent) { + if (i2c->type == &i2c_adapter_type) + break; + } + if (!i2c) + return NULL; + + /* Continue up the tree to find the root i2c adapter */ + i2c_root = to_i2c_adapter(i2c); + while (i2c_parent_is_i2c_adapter(i2c_root)) + i2c_root = i2c_parent_is_i2c_adapter(i2c_root); + + return i2c_root; +} +EXPORT_SYMBOL_GPL(i2c_root_adapter); + +struct i2c_mux_core *i2c_mux_alloc(struct i2c_adapter *parent, + struct device *dev, int max_adapters, + int sizeof_priv, u32 flags, + int (*select)(struct i2c_mux_core *, u32), + int (*deselect)(struct i2c_mux_core *, u32)) +{ + struct i2c_mux_core *muxc; + size_t mux_size; + + mux_size = struct_size(muxc, adapter, max_adapters); + muxc = devm_kzalloc(dev, size_add(mux_size, sizeof_priv), GFP_KERNEL); + if (!muxc) + return NULL; + if (sizeof_priv) + muxc->priv = &muxc->adapter[max_adapters]; + + muxc->parent = parent; + muxc->dev = dev; + if (flags & I2C_MUX_LOCKED) + muxc->mux_locked = true; + if (flags & I2C_MUX_ARBITRATOR) + muxc->arbitrator = true; + if (flags & I2C_MUX_GATE) + muxc->gate = true; + muxc->select = select; + muxc->deselect = deselect; + muxc->max_adapters = max_adapters; + + return muxc; +} +EXPORT_SYMBOL_GPL(i2c_mux_alloc); + +static const struct i2c_lock_operations i2c_mux_lock_ops = { + .lock_bus = i2c_mux_lock_bus, + .trylock_bus = i2c_mux_trylock_bus, + .unlock_bus = i2c_mux_unlock_bus, +}; + +static const struct i2c_lock_operations i2c_parent_lock_ops = { + .lock_bus = i2c_parent_lock_bus, + .trylock_bus = i2c_parent_trylock_bus, + .unlock_bus = i2c_parent_unlock_bus, +}; + +int i2c_mux_add_adapter(struct i2c_mux_core *muxc, + u32 force_nr, u32 chan_id, + unsigned int class) +{ + struct i2c_adapter *parent = muxc->parent; + struct i2c_mux_priv *priv; + char symlink_name[20]; + int ret; + + if (muxc->num_adapters >= muxc->max_adapters) { + dev_err(muxc->dev, "No room for more i2c-mux adapters\n"); + return -EINVAL; + } + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + /* Set up private adapter data */ + priv->muxc = muxc; + priv->chan_id = chan_id; + + /* Need to do algo dynamically because we don't know ahead + * of time what sort of physical adapter we'll be dealing with. + */ + if (parent->algo->master_xfer) { + if (muxc->mux_locked) + priv->algo.master_xfer = i2c_mux_master_xfer; + else + priv->algo.master_xfer = __i2c_mux_master_xfer; + } + if (parent->algo->master_xfer_atomic) + priv->algo.master_xfer_atomic = priv->algo.master_xfer; + + if (parent->algo->smbus_xfer) { + if (muxc->mux_locked) + priv->algo.smbus_xfer = i2c_mux_smbus_xfer; + else + priv->algo.smbus_xfer = __i2c_mux_smbus_xfer; + } + if (parent->algo->smbus_xfer_atomic) + priv->algo.smbus_xfer_atomic = priv->algo.smbus_xfer; + + priv->algo.functionality = i2c_mux_functionality; + + /* Now fill out new adapter structure */ + snprintf(priv->adap.name, sizeof(priv->adap.name), + "i2c-%d-mux (chan_id %d)", i2c_adapter_id(parent), chan_id); + priv->adap.owner = THIS_MODULE; + priv->adap.algo = &priv->algo; + priv->adap.algo_data = priv; + priv->adap.dev.parent = &parent->dev; + priv->adap.retries = parent->retries; + priv->adap.timeout = parent->timeout; + priv->adap.quirks = parent->quirks; + if (muxc->mux_locked) + priv->adap.lock_ops = &i2c_mux_lock_ops; + else + priv->adap.lock_ops = &i2c_parent_lock_ops; + + /* Sanity check on class */ + if (i2c_mux_parent_classes(parent) & class & ~I2C_CLASS_DEPRECATED) + dev_err(&parent->dev, + "Segment %d behind mux can't share classes with ancestors\n", + chan_id); + else + priv->adap.class = class; + + /* + * Try to populate the mux adapter's of_node, expands to + * nothing if !CONFIG_OF. + */ + if (muxc->dev->of_node) { + struct device_node *dev_node = muxc->dev->of_node; + struct device_node *mux_node, *child = NULL; + u32 reg; + + if (muxc->arbitrator) + mux_node = of_get_child_by_name(dev_node, "i2c-arb"); + else if (muxc->gate) + mux_node = of_get_child_by_name(dev_node, "i2c-gate"); + else + mux_node = of_get_child_by_name(dev_node, "i2c-mux"); + + if (mux_node) { + /* A "reg" property indicates an old-style DT entry */ + if (!of_property_read_u32(mux_node, "reg", ®)) { + of_node_put(mux_node); + mux_node = NULL; + } + } + + if (!mux_node) + mux_node = of_node_get(dev_node); + else if (muxc->arbitrator || muxc->gate) + child = of_node_get(mux_node); + + if (!child) { + for_each_child_of_node(mux_node, child) { + ret = of_property_read_u32(child, "reg", ®); + if (ret) + continue; + if (chan_id == reg) + break; + } + } + + priv->adap.dev.of_node = child; + of_node_put(mux_node); + } + + /* + * Associate the mux channel with an ACPI node. + */ + if (has_acpi_companion(muxc->dev)) + acpi_preset_companion(&priv->adap.dev, + ACPI_COMPANION(muxc->dev), + chan_id); + + if (force_nr) { + priv->adap.nr = force_nr; + ret = i2c_add_numbered_adapter(&priv->adap); + if (ret < 0) { + dev_err(&parent->dev, + "failed to add mux-adapter %u as bus %u (error=%d)\n", + chan_id, force_nr, ret); + goto err_free_priv; + } + } else { + ret = i2c_add_adapter(&priv->adap); + if (ret < 0) { + dev_err(&parent->dev, + "failed to add mux-adapter %u (error=%d)\n", + chan_id, ret); + goto err_free_priv; + } + } + + WARN(sysfs_create_link(&priv->adap.dev.kobj, &muxc->dev->kobj, + "mux_device"), + "can't create symlink to mux device\n"); + + snprintf(symlink_name, sizeof(symlink_name), "channel-%u", chan_id); + WARN(sysfs_create_link(&muxc->dev->kobj, &priv->adap.dev.kobj, + symlink_name), + "can't create symlink to channel %u\n", chan_id); + dev_info(&parent->dev, "Added multiplexed i2c bus %d\n", + i2c_adapter_id(&priv->adap)); + + muxc->adapter[muxc->num_adapters++] = &priv->adap; + return 0; + +err_free_priv: + kfree(priv); + return ret; +} +EXPORT_SYMBOL_GPL(i2c_mux_add_adapter); + +void i2c_mux_del_adapters(struct i2c_mux_core *muxc) +{ + char symlink_name[20]; + + while (muxc->num_adapters) { + struct i2c_adapter *adap = muxc->adapter[--muxc->num_adapters]; + struct i2c_mux_priv *priv = adap->algo_data; + struct device_node *np = adap->dev.of_node; + + muxc->adapter[muxc->num_adapters] = NULL; + + snprintf(symlink_name, sizeof(symlink_name), + "channel-%u", priv->chan_id); + sysfs_remove_link(&muxc->dev->kobj, symlink_name); + + sysfs_remove_link(&priv->adap.dev.kobj, "mux_device"); + i2c_del_adapter(adap); + of_node_put(np); + kfree(priv); + } +} +EXPORT_SYMBOL_GPL(i2c_mux_del_adapters); + +MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>"); +MODULE_DESCRIPTION("I2C driver for multiplexed I2C busses"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/i2c-slave-eeprom.c b/drivers/i2c/i2c-slave-eeprom.c new file mode 100644 index 000000000..5946c0d0a --- /dev/null +++ b/drivers/i2c/i2c-slave-eeprom.c @@ -0,0 +1,218 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * I2C slave mode EEPROM simulator + * + * Copyright (C) 2014 by Wolfram Sang, Sang Engineering <wsa@sang-engineering.com> + * Copyright (C) 2014 by Renesas Electronics Corporation + * + * Because most slave IP cores can only detect one I2C slave address anyhow, + * this driver does not support simulating EEPROM types which take more than + * one address. + */ + +/* + * FIXME: What to do if only 8 bits of a 16 bit address are sent? + * The ST-M24C64 sends only 0xff then. Needs verification with other + * EEPROMs, though. We currently use the 8 bit as a valid address. + */ + +#include <linux/bitfield.h> +#include <linux/firmware.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/sysfs.h> + +struct eeprom_data { + struct bin_attribute bin; + spinlock_t buffer_lock; + u16 buffer_idx; + u16 address_mask; + u8 num_address_bytes; + u8 idx_write_cnt; + bool read_only; + u8 buffer[]; +}; + +#define I2C_SLAVE_BYTELEN GENMASK(15, 0) +#define I2C_SLAVE_FLAG_ADDR16 BIT(16) +#define I2C_SLAVE_FLAG_RO BIT(17) +#define I2C_SLAVE_DEVICE_MAGIC(_len, _flags) ((_flags) | ((_len) - 1)) + +static int i2c_slave_eeprom_slave_cb(struct i2c_client *client, + enum i2c_slave_event event, u8 *val) +{ + struct eeprom_data *eeprom = i2c_get_clientdata(client); + + switch (event) { + case I2C_SLAVE_WRITE_RECEIVED: + if (eeprom->idx_write_cnt < eeprom->num_address_bytes) { + if (eeprom->idx_write_cnt == 0) + eeprom->buffer_idx = 0; + eeprom->buffer_idx = *val | (eeprom->buffer_idx << 8); + eeprom->idx_write_cnt++; + } else { + if (!eeprom->read_only) { + spin_lock(&eeprom->buffer_lock); + eeprom->buffer[eeprom->buffer_idx++ & eeprom->address_mask] = *val; + spin_unlock(&eeprom->buffer_lock); + } + } + break; + + case I2C_SLAVE_READ_PROCESSED: + /* The previous byte made it to the bus, get next one */ + eeprom->buffer_idx++; + fallthrough; + case I2C_SLAVE_READ_REQUESTED: + spin_lock(&eeprom->buffer_lock); + *val = eeprom->buffer[eeprom->buffer_idx & eeprom->address_mask]; + spin_unlock(&eeprom->buffer_lock); + /* + * Do not increment buffer_idx here, because we don't know if + * this byte will be actually used. Read Linux I2C slave docs + * for details. + */ + break; + + case I2C_SLAVE_STOP: + case I2C_SLAVE_WRITE_REQUESTED: + eeprom->idx_write_cnt = 0; + break; + + default: + break; + } + + return 0; +} + +static ssize_t i2c_slave_eeprom_bin_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *attr, char *buf, loff_t off, size_t count) +{ + struct eeprom_data *eeprom; + unsigned long flags; + + eeprom = dev_get_drvdata(kobj_to_dev(kobj)); + + spin_lock_irqsave(&eeprom->buffer_lock, flags); + memcpy(buf, &eeprom->buffer[off], count); + spin_unlock_irqrestore(&eeprom->buffer_lock, flags); + + return count; +} + +static ssize_t i2c_slave_eeprom_bin_write(struct file *filp, struct kobject *kobj, + struct bin_attribute *attr, char *buf, loff_t off, size_t count) +{ + struct eeprom_data *eeprom; + unsigned long flags; + + eeprom = dev_get_drvdata(kobj_to_dev(kobj)); + + spin_lock_irqsave(&eeprom->buffer_lock, flags); + memcpy(&eeprom->buffer[off], buf, count); + spin_unlock_irqrestore(&eeprom->buffer_lock, flags); + + return count; +} + +static int i2c_slave_init_eeprom_data(struct eeprom_data *eeprom, struct i2c_client *client, + unsigned int size) +{ + const struct firmware *fw; + const char *eeprom_data; + int ret = device_property_read_string(&client->dev, "firmware-name", &eeprom_data); + + if (!ret) { + ret = request_firmware_into_buf(&fw, eeprom_data, &client->dev, + eeprom->buffer, size); + if (ret) + return ret; + release_firmware(fw); + } else { + /* An empty eeprom typically has all bits set to 1 */ + memset(eeprom->buffer, 0xff, size); + } + return 0; +} + +static int i2c_slave_eeprom_probe(struct i2c_client *client) +{ + const struct i2c_device_id *id = i2c_client_get_device_id(client); + struct eeprom_data *eeprom; + int ret; + unsigned int size = FIELD_GET(I2C_SLAVE_BYTELEN, id->driver_data) + 1; + unsigned int flag_addr16 = FIELD_GET(I2C_SLAVE_FLAG_ADDR16, id->driver_data); + + eeprom = devm_kzalloc(&client->dev, sizeof(struct eeprom_data) + size, GFP_KERNEL); + if (!eeprom) + return -ENOMEM; + + eeprom->num_address_bytes = flag_addr16 ? 2 : 1; + eeprom->address_mask = size - 1; + eeprom->read_only = FIELD_GET(I2C_SLAVE_FLAG_RO, id->driver_data); + spin_lock_init(&eeprom->buffer_lock); + i2c_set_clientdata(client, eeprom); + + ret = i2c_slave_init_eeprom_data(eeprom, client, size); + if (ret) + return ret; + + sysfs_bin_attr_init(&eeprom->bin); + eeprom->bin.attr.name = "slave-eeprom"; + eeprom->bin.attr.mode = S_IRUSR | S_IWUSR; + eeprom->bin.read = i2c_slave_eeprom_bin_read; + eeprom->bin.write = i2c_slave_eeprom_bin_write; + eeprom->bin.size = size; + + ret = sysfs_create_bin_file(&client->dev.kobj, &eeprom->bin); + if (ret) + return ret; + + ret = i2c_slave_register(client, i2c_slave_eeprom_slave_cb); + if (ret) { + sysfs_remove_bin_file(&client->dev.kobj, &eeprom->bin); + return ret; + } + + return 0; +}; + +static void i2c_slave_eeprom_remove(struct i2c_client *client) +{ + struct eeprom_data *eeprom = i2c_get_clientdata(client); + + i2c_slave_unregister(client); + sysfs_remove_bin_file(&client->dev.kobj, &eeprom->bin); +} + +static const struct i2c_device_id i2c_slave_eeprom_id[] = { + { "slave-24c02", I2C_SLAVE_DEVICE_MAGIC(2048 / 8, 0) }, + { "slave-24c02ro", I2C_SLAVE_DEVICE_MAGIC(2048 / 8, I2C_SLAVE_FLAG_RO) }, + { "slave-24c32", I2C_SLAVE_DEVICE_MAGIC(32768 / 8, I2C_SLAVE_FLAG_ADDR16) }, + { "slave-24c32ro", I2C_SLAVE_DEVICE_MAGIC(32768 / 8, I2C_SLAVE_FLAG_ADDR16 | I2C_SLAVE_FLAG_RO) }, + { "slave-24c64", I2C_SLAVE_DEVICE_MAGIC(65536 / 8, I2C_SLAVE_FLAG_ADDR16) }, + { "slave-24c64ro", I2C_SLAVE_DEVICE_MAGIC(65536 / 8, I2C_SLAVE_FLAG_ADDR16 | I2C_SLAVE_FLAG_RO) }, + { "slave-24c512", I2C_SLAVE_DEVICE_MAGIC(524288 / 8, I2C_SLAVE_FLAG_ADDR16) }, + { "slave-24c512ro", I2C_SLAVE_DEVICE_MAGIC(524288 / 8, I2C_SLAVE_FLAG_ADDR16 | I2C_SLAVE_FLAG_RO) }, + { } +}; +MODULE_DEVICE_TABLE(i2c, i2c_slave_eeprom_id); + +static struct i2c_driver i2c_slave_eeprom_driver = { + .driver = { + .name = "i2c-slave-eeprom", + }, + .probe = i2c_slave_eeprom_probe, + .remove = i2c_slave_eeprom_remove, + .id_table = i2c_slave_eeprom_id, +}; +module_i2c_driver(i2c_slave_eeprom_driver); + +MODULE_AUTHOR("Wolfram Sang <wsa@sang-engineering.com>"); +MODULE_DESCRIPTION("I2C slave mode EEPROM simulator"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/i2c-slave-testunit.c b/drivers/i2c/i2c-slave-testunit.c new file mode 100644 index 000000000..a49642bba --- /dev/null +++ b/drivers/i2c/i2c-slave-testunit.c @@ -0,0 +1,182 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * I2C slave mode testunit + * + * Copyright (C) 2020 by Wolfram Sang, Sang Engineering <wsa@sang-engineering.com> + * Copyright (C) 2020 by Renesas Electronics Corporation + */ + +#include <linux/bitops.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/slab.h> +#include <linux/workqueue.h> /* FIXME: is system_long_wq the best choice? */ + +#define TU_CUR_VERSION 0x01 + +enum testunit_cmds { + TU_CMD_READ_BYTES = 1, /* save 0 for ABORT, RESET or similar */ + TU_CMD_HOST_NOTIFY, + TU_CMD_SMBUS_BLOCK_PROC_CALL, + TU_NUM_CMDS +}; + +enum testunit_regs { + TU_REG_CMD, + TU_REG_DATAL, + TU_REG_DATAH, + TU_REG_DELAY, + TU_NUM_REGS +}; + +enum testunit_flags { + TU_FLAG_IN_PROCESS, +}; + +struct testunit_data { + unsigned long flags; + u8 regs[TU_NUM_REGS]; + u8 reg_idx; + struct i2c_client *client; + struct delayed_work worker; +}; + +static void i2c_slave_testunit_work(struct work_struct *work) +{ + struct testunit_data *tu = container_of(work, struct testunit_data, worker.work); + struct i2c_msg msg; + u8 msgbuf[256]; + int ret = 0; + + msg.addr = I2C_CLIENT_END; + msg.buf = msgbuf; + + switch (tu->regs[TU_REG_CMD]) { + case TU_CMD_READ_BYTES: + msg.addr = tu->regs[TU_REG_DATAL]; + msg.flags = I2C_M_RD; + msg.len = tu->regs[TU_REG_DATAH]; + break; + + case TU_CMD_HOST_NOTIFY: + msg.addr = 0x08; + msg.flags = 0; + msg.len = 3; + msgbuf[0] = tu->client->addr; + msgbuf[1] = tu->regs[TU_REG_DATAL]; + msgbuf[2] = tu->regs[TU_REG_DATAH]; + break; + + default: + break; + } + + if (msg.addr != I2C_CLIENT_END) { + ret = i2c_transfer(tu->client->adapter, &msg, 1); + /* convert '0 msgs transferred' to errno */ + ret = (ret == 0) ? -EIO : ret; + } + + if (ret < 0) + dev_err(&tu->client->dev, "CMD%02X failed (%d)\n", tu->regs[TU_REG_CMD], ret); + + clear_bit(TU_FLAG_IN_PROCESS, &tu->flags); +} + +static int i2c_slave_testunit_slave_cb(struct i2c_client *client, + enum i2c_slave_event event, u8 *val) +{ + struct testunit_data *tu = i2c_get_clientdata(client); + bool is_proc_call = tu->reg_idx == 3 && tu->regs[TU_REG_DATAL] == 1 && + tu->regs[TU_REG_CMD] == TU_CMD_SMBUS_BLOCK_PROC_CALL; + int ret = 0; + + switch (event) { + case I2C_SLAVE_WRITE_RECEIVED: + if (test_bit(TU_FLAG_IN_PROCESS, &tu->flags)) + return -EBUSY; + + if (tu->reg_idx < TU_NUM_REGS) + tu->regs[tu->reg_idx] = *val; + else + ret = -EMSGSIZE; + + if (tu->reg_idx <= TU_NUM_REGS) + tu->reg_idx++; + + /* TU_REG_CMD always written at this point */ + if (tu->regs[TU_REG_CMD] >= TU_NUM_CMDS) + ret = -EINVAL; + + break; + + case I2C_SLAVE_STOP: + if (tu->reg_idx == TU_NUM_REGS) { + set_bit(TU_FLAG_IN_PROCESS, &tu->flags); + queue_delayed_work(system_long_wq, &tu->worker, + msecs_to_jiffies(10 * tu->regs[TU_REG_DELAY])); + } + fallthrough; + + case I2C_SLAVE_WRITE_REQUESTED: + memset(tu->regs, 0, TU_NUM_REGS); + tu->reg_idx = 0; + break; + + case I2C_SLAVE_READ_PROCESSED: + if (is_proc_call && tu->regs[TU_REG_DATAH]) + tu->regs[TU_REG_DATAH]--; + fallthrough; + + case I2C_SLAVE_READ_REQUESTED: + *val = is_proc_call ? tu->regs[TU_REG_DATAH] : TU_CUR_VERSION; + break; + } + + return ret; +} + +static int i2c_slave_testunit_probe(struct i2c_client *client) +{ + struct testunit_data *tu; + + tu = devm_kzalloc(&client->dev, sizeof(struct testunit_data), GFP_KERNEL); + if (!tu) + return -ENOMEM; + + tu->client = client; + i2c_set_clientdata(client, tu); + INIT_DELAYED_WORK(&tu->worker, i2c_slave_testunit_work); + + return i2c_slave_register(client, i2c_slave_testunit_slave_cb); +}; + +static void i2c_slave_testunit_remove(struct i2c_client *client) +{ + struct testunit_data *tu = i2c_get_clientdata(client); + + cancel_delayed_work_sync(&tu->worker); + i2c_slave_unregister(client); +} + +static const struct i2c_device_id i2c_slave_testunit_id[] = { + { "slave-testunit", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, i2c_slave_testunit_id); + +static struct i2c_driver i2c_slave_testunit_driver = { + .driver = { + .name = "i2c-slave-testunit", + }, + .probe = i2c_slave_testunit_probe, + .remove = i2c_slave_testunit_remove, + .id_table = i2c_slave_testunit_id, +}; +module_i2c_driver(i2c_slave_testunit_driver); + +MODULE_AUTHOR("Wolfram Sang <wsa@sang-engineering.com>"); +MODULE_DESCRIPTION("I2C slave mode test unit"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/i2c-smbus.c b/drivers/i2c/i2c-smbus.c new file mode 100644 index 000000000..138c3f5e0 --- /dev/null +++ b/drivers/i2c/i2c-smbus.c @@ -0,0 +1,415 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * i2c-smbus.c - SMBus extensions to the I2C protocol + * + * Copyright (C) 2008 David Brownell + * Copyright (C) 2010-2019 Jean Delvare <jdelvare@suse.de> + */ + +#include <linux/device.h> +#include <linux/dmi.h> +#include <linux/i2c.h> +#include <linux/i2c-smbus.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/property.h> +#include <linux/slab.h> +#include <linux/workqueue.h> + +struct i2c_smbus_alert { + struct work_struct alert; + struct i2c_client *ara; /* Alert response address */ +}; + +struct alert_data { + unsigned short addr; + enum i2c_alert_protocol type; + unsigned int data; +}; + +/* If this is the alerting device, notify its driver */ +static int smbus_do_alert(struct device *dev, void *addrp) +{ + struct i2c_client *client = i2c_verify_client(dev); + struct alert_data *data = addrp; + struct i2c_driver *driver; + + if (!client || client->addr != data->addr) + return 0; + if (client->flags & I2C_CLIENT_TEN) + return 0; + + /* + * Drivers should either disable alerts, or provide at least + * a minimal handler. Lock so the driver won't change. + */ + device_lock(dev); + if (client->dev.driver) { + driver = to_i2c_driver(client->dev.driver); + if (driver->alert) + driver->alert(client, data->type, data->data); + else + dev_warn(&client->dev, "no driver alert()!\n"); + } else + dev_dbg(&client->dev, "alert with no driver\n"); + device_unlock(dev); + + /* Stop iterating after we find the device */ + return -EBUSY; +} + +/* + * The alert IRQ handler needs to hand work off to a task which can issue + * SMBus calls, because those sleeping calls can't be made in IRQ context. + */ +static irqreturn_t smbus_alert(int irq, void *d) +{ + struct i2c_smbus_alert *alert = d; + struct i2c_client *ara; + + ara = alert->ara; + + for (;;) { + s32 status; + struct alert_data data; + + /* + * Devices with pending alerts reply in address order, low + * to high, because of slave transmit arbitration. After + * responding, an SMBus device stops asserting SMBALERT#. + * + * Note that SMBus 2.0 reserves 10-bit addresses for future + * use. We neither handle them, nor try to use PEC here. + */ + status = i2c_smbus_read_byte(ara); + if (status < 0) + break; + + data.data = status & 1; + data.addr = status >> 1; + data.type = I2C_PROTOCOL_SMBUS_ALERT; + + dev_dbg(&ara->dev, "SMBALERT# from dev 0x%02x, flag %d\n", + data.addr, data.data); + + /* Notify driver for the device which issued the alert */ + device_for_each_child(&ara->adapter->dev, &data, + smbus_do_alert); + } + + return IRQ_HANDLED; +} + +static void smbalert_work(struct work_struct *work) +{ + struct i2c_smbus_alert *alert; + + alert = container_of(work, struct i2c_smbus_alert, alert); + + smbus_alert(0, alert); + +} + +/* Setup SMBALERT# infrastructure */ +static int smbalert_probe(struct i2c_client *ara) +{ + struct i2c_smbus_alert_setup *setup = dev_get_platdata(&ara->dev); + struct i2c_smbus_alert *alert; + struct i2c_adapter *adapter = ara->adapter; + int res, irq; + + alert = devm_kzalloc(&ara->dev, sizeof(struct i2c_smbus_alert), + GFP_KERNEL); + if (!alert) + return -ENOMEM; + + if (setup) { + irq = setup->irq; + } else { + irq = fwnode_irq_get_byname(dev_fwnode(adapter->dev.parent), + "smbus_alert"); + if (irq <= 0) + return irq; + } + + INIT_WORK(&alert->alert, smbalert_work); + alert->ara = ara; + + if (irq > 0) { + res = devm_request_threaded_irq(&ara->dev, irq, + NULL, smbus_alert, + IRQF_SHARED | IRQF_ONESHOT, + "smbus_alert", alert); + if (res) + return res; + } + + i2c_set_clientdata(ara, alert); + dev_info(&adapter->dev, "supports SMBALERT#\n"); + + return 0; +} + +/* IRQ and memory resources are managed so they are freed automatically */ +static void smbalert_remove(struct i2c_client *ara) +{ + struct i2c_smbus_alert *alert = i2c_get_clientdata(ara); + + cancel_work_sync(&alert->alert); +} + +static const struct i2c_device_id smbalert_ids[] = { + { "smbus_alert", 0 }, + { /* LIST END */ } +}; +MODULE_DEVICE_TABLE(i2c, smbalert_ids); + +static struct i2c_driver smbalert_driver = { + .driver = { + .name = "smbus_alert", + }, + .probe = smbalert_probe, + .remove = smbalert_remove, + .id_table = smbalert_ids, +}; + +/** + * i2c_handle_smbus_alert - Handle an SMBus alert + * @ara: the ARA client on the relevant adapter + * Context: can't sleep + * + * Helper function to be called from an I2C bus driver's interrupt + * handler. It will schedule the alert work, in turn calling the + * corresponding I2C device driver's alert function. + * + * It is assumed that ara is a valid i2c client previously returned by + * i2c_new_smbus_alert_device(). + */ +int i2c_handle_smbus_alert(struct i2c_client *ara) +{ + struct i2c_smbus_alert *alert = i2c_get_clientdata(ara); + + return schedule_work(&alert->alert); +} +EXPORT_SYMBOL_GPL(i2c_handle_smbus_alert); + +module_i2c_driver(smbalert_driver); + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +#define SMBUS_HOST_NOTIFY_LEN 3 +struct i2c_slave_host_notify_status { + u8 index; + u8 addr; +}; + +static int i2c_slave_host_notify_cb(struct i2c_client *client, + enum i2c_slave_event event, u8 *val) +{ + struct i2c_slave_host_notify_status *status = client->dev.platform_data; + + switch (event) { + case I2C_SLAVE_WRITE_RECEIVED: + /* We only retrieve the first byte received (addr) + * since there is currently no support to retrieve the data + * parameter from the client. + */ + if (status->index == 0) + status->addr = *val; + if (status->index < U8_MAX) + status->index++; + break; + case I2C_SLAVE_STOP: + if (status->index == SMBUS_HOST_NOTIFY_LEN) + i2c_handle_smbus_host_notify(client->adapter, + status->addr); + fallthrough; + case I2C_SLAVE_WRITE_REQUESTED: + status->index = 0; + break; + case I2C_SLAVE_READ_REQUESTED: + case I2C_SLAVE_READ_PROCESSED: + *val = 0xff; + break; + } + + return 0; +} + +/** + * i2c_new_slave_host_notify_device - get a client for SMBus host-notify support + * @adapter: the target adapter + * Context: can sleep + * + * Setup handling of the SMBus host-notify protocol on a given I2C bus segment. + * + * Handling is done by creating a device and its callback and handling data + * received via the SMBus host-notify address (0x8) + * + * This returns the client, which should be ultimately freed using + * i2c_free_slave_host_notify_device(); or an ERRPTR to indicate an error. + */ +struct i2c_client *i2c_new_slave_host_notify_device(struct i2c_adapter *adapter) +{ + struct i2c_board_info host_notify_board_info = { + I2C_BOARD_INFO("smbus_host_notify", 0x08), + .flags = I2C_CLIENT_SLAVE, + }; + struct i2c_slave_host_notify_status *status; + struct i2c_client *client; + int ret; + + status = kzalloc(sizeof(struct i2c_slave_host_notify_status), + GFP_KERNEL); + if (!status) + return ERR_PTR(-ENOMEM); + + host_notify_board_info.platform_data = status; + + client = i2c_new_client_device(adapter, &host_notify_board_info); + if (IS_ERR(client)) { + kfree(status); + return client; + } + + ret = i2c_slave_register(client, i2c_slave_host_notify_cb); + if (ret) { + i2c_unregister_device(client); + kfree(status); + return ERR_PTR(ret); + } + + return client; +} +EXPORT_SYMBOL_GPL(i2c_new_slave_host_notify_device); + +/** + * i2c_free_slave_host_notify_device - free the client for SMBus host-notify + * support + * @client: the client to free + * Context: can sleep + * + * Free the i2c_client allocated via i2c_new_slave_host_notify_device + */ +void i2c_free_slave_host_notify_device(struct i2c_client *client) +{ + if (IS_ERR_OR_NULL(client)) + return; + + i2c_slave_unregister(client); + kfree(client->dev.platform_data); + i2c_unregister_device(client); +} +EXPORT_SYMBOL_GPL(i2c_free_slave_host_notify_device); +#endif + +/* + * SPD is not part of SMBus but we include it here for convenience as the + * target systems are the same. + * Restrictions to automatic SPD instantiation: + * - Only works if all filled slots have the same memory type + * - Only works for DDR2, DDR3 and DDR4 for now + * - Only works on systems with 1 to 4 memory slots + */ +#if IS_ENABLED(CONFIG_DMI) +void i2c_register_spd(struct i2c_adapter *adap) +{ + int n, slot_count = 0, dimm_count = 0; + u16 handle; + u8 common_mem_type = 0x0, mem_type; + u64 mem_size; + const char *name; + + while ((handle = dmi_memdev_handle(slot_count)) != 0xffff) { + slot_count++; + + /* Skip empty slots */ + mem_size = dmi_memdev_size(handle); + if (!mem_size) + continue; + + /* Skip undefined memory type */ + mem_type = dmi_memdev_type(handle); + if (mem_type <= 0x02) /* Invalid, Other, Unknown */ + continue; + + if (!common_mem_type) { + /* First filled slot */ + common_mem_type = mem_type; + } else { + /* Check that all filled slots have the same type */ + if (mem_type != common_mem_type) { + dev_warn(&adap->dev, + "Different memory types mixed, not instantiating SPD\n"); + return; + } + } + dimm_count++; + } + + /* No useful DMI data, bail out */ + if (!dimm_count) + return; + + dev_info(&adap->dev, "%d/%d memory slots populated (from DMI)\n", + dimm_count, slot_count); + + if (slot_count > 4) { + dev_warn(&adap->dev, + "Systems with more than 4 memory slots not supported yet, not instantiating SPD\n"); + return; + } + + /* + * Memory types could be found at section 7.18.2 (Memory Device — Type), table 78 + * https://www.dmtf.org/sites/default/files/standards/documents/DSP0134_3.6.0.pdf + */ + switch (common_mem_type) { + case 0x12: /* DDR */ + case 0x13: /* DDR2 */ + case 0x18: /* DDR3 */ + case 0x1B: /* LPDDR */ + case 0x1C: /* LPDDR2 */ + case 0x1D: /* LPDDR3 */ + name = "spd"; + break; + case 0x1A: /* DDR4 */ + case 0x1E: /* LPDDR4 */ + name = "ee1004"; + break; + default: + dev_info(&adap->dev, + "Memory type 0x%02x not supported yet, not instantiating SPD\n", + common_mem_type); + return; + } + + /* + * We don't know in which slots the memory modules are. We could + * try to guess from the slot names, but that would be rather complex + * and unreliable, so better probe all possible addresses until we + * have found all memory modules. + */ + for (n = 0; n < slot_count && dimm_count; n++) { + struct i2c_board_info info; + unsigned short addr_list[2]; + + memset(&info, 0, sizeof(struct i2c_board_info)); + strscpy(info.type, name, I2C_NAME_SIZE); + addr_list[0] = 0x50 + n; + addr_list[1] = I2C_CLIENT_END; + + if (!IS_ERR(i2c_new_scanned_device(adap, &info, addr_list, NULL))) { + dev_info(&adap->dev, + "Successfully instantiated SPD at 0x%hx\n", + addr_list[0]); + dimm_count--; + } + } +} +EXPORT_SYMBOL_GPL(i2c_register_spd); +#endif + +MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>"); +MODULE_DESCRIPTION("SMBus protocol extensions support"); +MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/i2c-stub.c b/drivers/i2c/i2c-stub.c new file mode 100644 index 000000000..d642cad21 --- /dev/null +++ b/drivers/i2c/i2c-stub.c @@ -0,0 +1,413 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + i2c-stub.c - I2C/SMBus chip emulator + + Copyright (c) 2004 Mark M. Hoffman <mhoffman@lightlink.com> + Copyright (C) 2007-2014 Jean Delvare <jdelvare@suse.de> + +*/ + +#define pr_fmt(fmt) "i2c-stub: " fmt + +#include <linux/errno.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/slab.h> + +#define MAX_CHIPS 10 + +/* + * Support for I2C_FUNC_SMBUS_BLOCK_DATA is disabled by default and must + * be enabled explicitly by setting the I2C_FUNC_SMBUS_BLOCK_DATA bits + * in the 'functionality' module parameter. + */ +#define STUB_FUNC_DEFAULT \ + (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | \ + I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | \ + I2C_FUNC_SMBUS_I2C_BLOCK) + +#define STUB_FUNC_ALL \ + (STUB_FUNC_DEFAULT | I2C_FUNC_SMBUS_BLOCK_DATA) + +static unsigned short chip_addr[MAX_CHIPS]; +module_param_array(chip_addr, ushort, NULL, S_IRUGO); +MODULE_PARM_DESC(chip_addr, + "Chip addresses (up to 10, between 0x03 and 0x77)"); + +static unsigned long functionality = STUB_FUNC_DEFAULT; +module_param(functionality, ulong, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(functionality, "Override functionality bitfield"); + +/* Some chips have banked register ranges */ + +static u8 bank_reg[MAX_CHIPS]; +module_param_array(bank_reg, byte, NULL, S_IRUGO); +MODULE_PARM_DESC(bank_reg, "Bank register"); + +static u8 bank_mask[MAX_CHIPS]; +module_param_array(bank_mask, byte, NULL, S_IRUGO); +MODULE_PARM_DESC(bank_mask, "Bank value mask"); + +static u8 bank_start[MAX_CHIPS]; +module_param_array(bank_start, byte, NULL, S_IRUGO); +MODULE_PARM_DESC(bank_start, "First banked register"); + +static u8 bank_end[MAX_CHIPS]; +module_param_array(bank_end, byte, NULL, S_IRUGO); +MODULE_PARM_DESC(bank_end, "Last banked register"); + +struct smbus_block_data { + struct list_head node; + u8 command; + u8 len; + u8 block[I2C_SMBUS_BLOCK_MAX]; +}; + +struct stub_chip { + u8 pointer; + u16 words[256]; /* Byte operations use the LSB as per SMBus + specification */ + struct list_head smbus_blocks; + + /* For chips with banks, extra registers are allocated dynamically */ + u8 bank_reg; + u8 bank_shift; + u8 bank_mask; + u8 bank_sel; /* Currently selected bank */ + u8 bank_start; + u8 bank_end; + u16 bank_size; + u16 *bank_words; /* Room for bank_mask * bank_size registers */ +}; + +static struct stub_chip *stub_chips; +static int stub_chips_nr; + +static struct smbus_block_data *stub_find_block(struct device *dev, + struct stub_chip *chip, + u8 command, bool create) +{ + struct smbus_block_data *b, *rb = NULL; + + list_for_each_entry(b, &chip->smbus_blocks, node) { + if (b->command == command) { + rb = b; + break; + } + } + if (rb == NULL && create) { + rb = devm_kzalloc(dev, sizeof(*rb), GFP_KERNEL); + if (rb == NULL) + return rb; + rb->command = command; + list_add(&rb->node, &chip->smbus_blocks); + } + return rb; +} + +static u16 *stub_get_wordp(struct stub_chip *chip, u8 offset) +{ + if (chip->bank_sel && + offset >= chip->bank_start && offset <= chip->bank_end) + return chip->bank_words + + (chip->bank_sel - 1) * chip->bank_size + + offset - chip->bank_start; + else + return chip->words + offset; +} + +/* Return negative errno on error. */ +static s32 stub_xfer(struct i2c_adapter *adap, u16 addr, unsigned short flags, + char read_write, u8 command, int size, union i2c_smbus_data *data) +{ + s32 ret; + int i, len; + struct stub_chip *chip = NULL; + struct smbus_block_data *b; + u16 *wordp; + + /* Search for the right chip */ + for (i = 0; i < stub_chips_nr; i++) { + if (addr == chip_addr[i]) { + chip = stub_chips + i; + break; + } + } + if (!chip) + return -ENODEV; + + switch (size) { + + case I2C_SMBUS_QUICK: + dev_dbg(&adap->dev, "smbus quick - addr 0x%02x\n", addr); + ret = 0; + break; + + case I2C_SMBUS_BYTE: + if (read_write == I2C_SMBUS_WRITE) { + chip->pointer = command; + dev_dbg(&adap->dev, + "smbus byte - addr 0x%02x, wrote 0x%02x.\n", + addr, command); + } else { + wordp = stub_get_wordp(chip, chip->pointer++); + data->byte = *wordp & 0xff; + dev_dbg(&adap->dev, + "smbus byte - addr 0x%02x, read 0x%02x.\n", + addr, data->byte); + } + + ret = 0; + break; + + case I2C_SMBUS_BYTE_DATA: + wordp = stub_get_wordp(chip, command); + if (read_write == I2C_SMBUS_WRITE) { + *wordp &= 0xff00; + *wordp |= data->byte; + dev_dbg(&adap->dev, + "smbus byte data - addr 0x%02x, wrote 0x%02x at 0x%02x.\n", + addr, data->byte, command); + + /* Set the bank as needed */ + if (chip->bank_words && command == chip->bank_reg) { + chip->bank_sel = + (data->byte >> chip->bank_shift) + & chip->bank_mask; + dev_dbg(&adap->dev, + "switching to bank %u.\n", + chip->bank_sel); + } + } else { + data->byte = *wordp & 0xff; + dev_dbg(&adap->dev, + "smbus byte data - addr 0x%02x, read 0x%02x at 0x%02x.\n", + addr, data->byte, command); + } + chip->pointer = command + 1; + + ret = 0; + break; + + case I2C_SMBUS_WORD_DATA: + wordp = stub_get_wordp(chip, command); + if (read_write == I2C_SMBUS_WRITE) { + *wordp = data->word; + dev_dbg(&adap->dev, + "smbus word data - addr 0x%02x, wrote 0x%04x at 0x%02x.\n", + addr, data->word, command); + } else { + data->word = *wordp; + dev_dbg(&adap->dev, + "smbus word data - addr 0x%02x, read 0x%04x at 0x%02x.\n", + addr, data->word, command); + } + + ret = 0; + break; + + case I2C_SMBUS_I2C_BLOCK_DATA: + /* + * We ignore banks here, because banked chips don't use I2C + * block transfers + */ + if (data->block[0] > 256 - command) /* Avoid overrun */ + data->block[0] = 256 - command; + len = data->block[0]; + if (read_write == I2C_SMBUS_WRITE) { + for (i = 0; i < len; i++) { + chip->words[command + i] &= 0xff00; + chip->words[command + i] |= data->block[1 + i]; + } + dev_dbg(&adap->dev, + "i2c block data - addr 0x%02x, wrote %d bytes at 0x%02x.\n", + addr, len, command); + } else { + for (i = 0; i < len; i++) { + data->block[1 + i] = + chip->words[command + i] & 0xff; + } + dev_dbg(&adap->dev, + "i2c block data - addr 0x%02x, read %d bytes at 0x%02x.\n", + addr, len, command); + } + + ret = 0; + break; + + case I2C_SMBUS_BLOCK_DATA: + /* + * We ignore banks here, because chips typically don't use both + * banks and SMBus block transfers + */ + b = stub_find_block(&adap->dev, chip, command, false); + if (read_write == I2C_SMBUS_WRITE) { + len = data->block[0]; + if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) { + ret = -EINVAL; + break; + } + if (b == NULL) { + b = stub_find_block(&adap->dev, chip, command, + true); + if (b == NULL) { + ret = -ENOMEM; + break; + } + } + /* Largest write sets read block length */ + if (len > b->len) + b->len = len; + for (i = 0; i < len; i++) + b->block[i] = data->block[i + 1]; + /* update for byte and word commands */ + chip->words[command] = (b->block[0] << 8) | b->len; + dev_dbg(&adap->dev, + "smbus block data - addr 0x%02x, wrote %d bytes at 0x%02x.\n", + addr, len, command); + } else { + if (b == NULL) { + dev_dbg(&adap->dev, + "SMBus block read command without prior block write not supported\n"); + ret = -EOPNOTSUPP; + break; + } + len = b->len; + data->block[0] = len; + for (i = 0; i < len; i++) + data->block[i + 1] = b->block[i]; + dev_dbg(&adap->dev, + "smbus block data - addr 0x%02x, read %d bytes at 0x%02x.\n", + addr, len, command); + } + + ret = 0; + break; + + default: + dev_dbg(&adap->dev, "Unsupported I2C/SMBus command\n"); + ret = -EOPNOTSUPP; + break; + } /* switch (size) */ + + return ret; +} + +static u32 stub_func(struct i2c_adapter *adapter) +{ + return STUB_FUNC_ALL & functionality; +} + +static const struct i2c_algorithm smbus_algorithm = { + .functionality = stub_func, + .smbus_xfer = stub_xfer, +}; + +static struct i2c_adapter stub_adapter = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .algo = &smbus_algorithm, + .name = "SMBus stub driver", +}; + +static int __init i2c_stub_allocate_banks(int i) +{ + struct stub_chip *chip = stub_chips + i; + + chip->bank_reg = bank_reg[i]; + chip->bank_start = bank_start[i]; + chip->bank_end = bank_end[i]; + chip->bank_size = bank_end[i] - bank_start[i] + 1; + + /* We assume that all bits in the mask are contiguous */ + chip->bank_mask = bank_mask[i]; + while (!(chip->bank_mask & 1)) { + chip->bank_shift++; + chip->bank_mask >>= 1; + } + + chip->bank_words = kcalloc(chip->bank_mask * chip->bank_size, + sizeof(u16), + GFP_KERNEL); + if (!chip->bank_words) + return -ENOMEM; + + pr_debug("Allocated %u banks of %u words each (registers 0x%02x to 0x%02x)\n", + chip->bank_mask, chip->bank_size, chip->bank_start, + chip->bank_end); + + return 0; +} + +static void i2c_stub_free(void) +{ + int i; + + for (i = 0; i < stub_chips_nr; i++) + kfree(stub_chips[i].bank_words); + kfree(stub_chips); +} + +static int __init i2c_stub_init(void) +{ + int i, ret; + + if (!chip_addr[0]) { + pr_err("Please specify a chip address\n"); + return -ENODEV; + } + + for (i = 0; i < MAX_CHIPS && chip_addr[i]; i++) { + if (chip_addr[i] < 0x03 || chip_addr[i] > 0x77) { + pr_err("Invalid chip address 0x%02x\n", + chip_addr[i]); + return -EINVAL; + } + + pr_info("Virtual chip at 0x%02x\n", chip_addr[i]); + } + + /* Allocate memory for all chips at once */ + stub_chips_nr = i; + stub_chips = kcalloc(stub_chips_nr, sizeof(struct stub_chip), + GFP_KERNEL); + if (!stub_chips) + return -ENOMEM; + + for (i = 0; i < stub_chips_nr; i++) { + INIT_LIST_HEAD(&stub_chips[i].smbus_blocks); + + /* Allocate extra memory for banked register ranges */ + if (bank_mask[i]) { + ret = i2c_stub_allocate_banks(i); + if (ret) + goto fail_free; + } + } + + ret = i2c_add_adapter(&stub_adapter); + if (ret) + goto fail_free; + + return 0; + + fail_free: + i2c_stub_free(); + return ret; +} + +static void __exit i2c_stub_exit(void) +{ + i2c_del_adapter(&stub_adapter); + i2c_stub_free(); +} + +MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>"); +MODULE_DESCRIPTION("I2C stub driver"); +MODULE_LICENSE("GPL"); + +module_init(i2c_stub_init); +module_exit(i2c_stub_exit); diff --git a/drivers/i2c/muxes/Kconfig b/drivers/i2c/muxes/Kconfig new file mode 100644 index 000000000..db1b90576 --- /dev/null +++ b/drivers/i2c/muxes/Kconfig @@ -0,0 +1,122 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Multiplexer I2C chip drivers configuration +# + +menu "Multiplexer I2C Chip support" + depends on I2C_MUX + +config I2C_ARB_GPIO_CHALLENGE + tristate "GPIO-based I2C arbitration" + depends on GPIOLIB || COMPILE_TEST + depends on OF + help + If you say yes to this option, support will be included for an + I2C multimaster arbitration scheme using GPIOs and a challenge & + response mechanism where masters have to claim the bus by asserting + a GPIO. + + This driver can also be built as a module. If so, the module + will be called i2c-arb-gpio-challenge. + +config I2C_MUX_GPIO + tristate "GPIO-based I2C multiplexer" + depends on GPIOLIB + help + If you say yes to this option, support will be included for a + GPIO based I2C multiplexer. This driver provides access to + I2C busses connected through a MUX, which is controlled + through GPIO pins. + + This driver can also be built as a module. If so, the module + will be called i2c-mux-gpio. + +config I2C_MUX_GPMUX + tristate "General Purpose I2C multiplexer" + select MULTIPLEXER + depends on OF + help + If you say yes to this option, support will be included for a + general purpose I2C multiplexer. This driver provides access to + I2C busses connected through a MUX, which in turn is controlled + by a MUX-controller from the MUX subsystem. + + This driver can also be built as a module. If so, the module + will be called i2c-mux-gpmux. + +config I2C_MUX_LTC4306 + tristate "LTC LTC4306/5 I2C multiplexer" + select GPIOLIB + select REGMAP_I2C + help + If you say yes here you get support for the Analog Devices + LTC4306 or LTC4305 I2C mux/switch devices. + + This driver can also be built as a module. If so, the module + will be called i2c-mux-ltc4306. + +config I2C_MUX_PCA9541 + tristate "NXP PCA9541 I2C Master Selector" + help + If you say yes here you get support for the NXP PCA9541 + I2C Master Selector. + + This driver can also be built as a module. If so, the module + will be called i2c-mux-pca9541. + +config I2C_MUX_PCA954x + tristate "NXP PCA954x/PCA984x and Maxim MAX735x/MAX736x I2C Mux/switches" + depends on GPIOLIB || COMPILE_TEST + help + If you say yes here you get support for NXP PCA954x/PCA984x + and Maxim MAX735x/MAX736x I2C mux/switch devices. + + This driver can also be built as a module. If so, the module + will be called i2c-mux-pca954x. + +config I2C_MUX_PINCTRL + tristate "pinctrl-based I2C multiplexer" + depends on PINCTRL + depends on OF + help + If you say yes to this option, support will be included for an I2C + multiplexer that uses the pinctrl subsystem, i.e. pin multiplexing. + This is useful for SoCs whose I2C module's signals can be routed to + different sets of pins at run-time. + + This driver can also be built as a module. If so, the module will be + called i2c-mux-pinctrl. + +config I2C_MUX_REG + tristate "Register-based I2C multiplexer" + depends on HAS_IOMEM + help + If you say yes to this option, support will be included for a + register based I2C multiplexer. This driver provides access to + I2C busses connected through a MUX, which is controlled + by a single register. + + This driver can also be built as a module. If so, the module + will be called i2c-mux-reg. + +config I2C_DEMUX_PINCTRL + tristate "pinctrl-based I2C demultiplexer" + depends on PINCTRL && OF + select OF_DYNAMIC + help + If you say yes to this option, support will be included for an I2C + demultiplexer that uses the pinctrl subsystem. This is useful if you + want to change the I2C master at run-time depending on features. + +config I2C_MUX_MLXCPLD + tristate "Mellanox CPLD based I2C multiplexer" + help + If you say yes to this option, support will be included for a + CPLD based I2C multiplexer. This driver provides access to + I2C busses connected through a MUX, which is controlled + by a CPLD register. + + This driver can also be built as a module. If so, the module + will be called i2c-mux-mlxcpld. + +endmenu diff --git a/drivers/i2c/muxes/Makefile b/drivers/i2c/muxes/Makefile new file mode 100644 index 000000000..6d9d865e8 --- /dev/null +++ b/drivers/i2c/muxes/Makefile @@ -0,0 +1,18 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for multiplexer I2C chip drivers. + +obj-$(CONFIG_I2C_ARB_GPIO_CHALLENGE) += i2c-arb-gpio-challenge.o + +obj-$(CONFIG_I2C_DEMUX_PINCTRL) += i2c-demux-pinctrl.o + +obj-$(CONFIG_I2C_MUX_GPIO) += i2c-mux-gpio.o +obj-$(CONFIG_I2C_MUX_GPMUX) += i2c-mux-gpmux.o +obj-$(CONFIG_I2C_MUX_LTC4306) += i2c-mux-ltc4306.o +obj-$(CONFIG_I2C_MUX_MLXCPLD) += i2c-mux-mlxcpld.o +obj-$(CONFIG_I2C_MUX_PCA9541) += i2c-mux-pca9541.o +obj-$(CONFIG_I2C_MUX_PCA954x) += i2c-mux-pca954x.o +obj-$(CONFIG_I2C_MUX_PINCTRL) += i2c-mux-pinctrl.o +obj-$(CONFIG_I2C_MUX_REG) += i2c-mux-reg.o + +ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG diff --git a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c new file mode 100644 index 000000000..24168e9f7 --- /dev/null +++ b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c @@ -0,0 +1,205 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * GPIO-based I2C Arbitration Using a Challenge & Response Mechanism + * + * Copyright (C) 2012 Google, Inc + */ + +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/kernel.h> +#include <linux/i2c.h> +#include <linux/i2c-mux.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + + +/** + * struct i2c_arbitrator_data - Driver data for I2C arbitrator + * + * @our_gpio: GPIO descriptor we'll use to claim. + * @their_gpio: GPIO descriptor that the other side will use to claim. + * @slew_delay_us: microseconds to wait for a GPIO to go high. + * @wait_retry_us: we'll attempt another claim after this many microseconds. + * @wait_free_us: we'll give up after this many microseconds. + */ + +struct i2c_arbitrator_data { + struct gpio_desc *our_gpio; + struct gpio_desc *their_gpio; + unsigned int slew_delay_us; + unsigned int wait_retry_us; + unsigned int wait_free_us; +}; + + +/* + * i2c_arbitrator_select - claim the I2C bus + * + * Use the GPIO-based signalling protocol; return -EBUSY if we fail. + */ +static int i2c_arbitrator_select(struct i2c_mux_core *muxc, u32 chan) +{ + const struct i2c_arbitrator_data *arb = i2c_mux_priv(muxc); + unsigned long stop_retry, stop_time; + + /* Start a round of trying to claim the bus */ + stop_time = jiffies + usecs_to_jiffies(arb->wait_free_us) + 1; + do { + /* Indicate that we want to claim the bus */ + gpiod_set_value(arb->our_gpio, 1); + udelay(arb->slew_delay_us); + + /* Wait for the other master to release it */ + stop_retry = jiffies + usecs_to_jiffies(arb->wait_retry_us) + 1; + while (time_before(jiffies, stop_retry)) { + int gpio_val = gpiod_get_value(arb->their_gpio); + + if (!gpio_val) { + /* We got it, so return */ + return 0; + } + + usleep_range(50, 200); + } + + /* It didn't release, so give up, wait, and try again */ + gpiod_set_value(arb->our_gpio, 0); + + usleep_range(arb->wait_retry_us, arb->wait_retry_us * 2); + } while (time_before(jiffies, stop_time)); + + /* Give up, release our claim */ + gpiod_set_value(arb->our_gpio, 0); + udelay(arb->slew_delay_us); + dev_err(muxc->dev, "Could not claim bus, timeout\n"); + return -EBUSY; +} + +/* + * i2c_arbitrator_deselect - release the I2C bus + * + * Release the I2C bus using the GPIO-based signalling protocol. + */ +static int i2c_arbitrator_deselect(struct i2c_mux_core *muxc, u32 chan) +{ + const struct i2c_arbitrator_data *arb = i2c_mux_priv(muxc); + + /* Release the bus and wait for the other master to notice */ + gpiod_set_value(arb->our_gpio, 0); + udelay(arb->slew_delay_us); + + return 0; +} + +static int i2c_arbitrator_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct device_node *parent_np; + struct i2c_mux_core *muxc; + struct i2c_arbitrator_data *arb; + struct gpio_desc *dummy; + int ret; + + /* We only support probing from device tree; no platform_data */ + if (!np) { + dev_err(dev, "Cannot find device tree node\n"); + return -ENODEV; + } + if (dev_get_platdata(dev)) { + dev_err(dev, "Platform data is not supported\n"); + return -EINVAL; + } + + muxc = i2c_mux_alloc(NULL, dev, 1, sizeof(*arb), I2C_MUX_ARBITRATOR, + i2c_arbitrator_select, i2c_arbitrator_deselect); + if (!muxc) + return -ENOMEM; + arb = i2c_mux_priv(muxc); + + platform_set_drvdata(pdev, muxc); + + /* Request GPIOs, our GPIO as unclaimed to begin with */ + arb->our_gpio = devm_gpiod_get(dev, "our-claim", GPIOD_OUT_LOW); + if (IS_ERR(arb->our_gpio)) { + dev_err(dev, "could not get \"our-claim\" GPIO (%ld)\n", + PTR_ERR(arb->our_gpio)); + return PTR_ERR(arb->our_gpio); + } + + arb->their_gpio = devm_gpiod_get(dev, "their-claim", GPIOD_IN); + if (IS_ERR(arb->their_gpio)) { + dev_err(dev, "could not get \"their-claim\" GPIO (%ld)\n", + PTR_ERR(arb->their_gpio)); + return PTR_ERR(arb->their_gpio); + } + + /* At the moment we only support a single two master (us + 1 other) */ + dummy = devm_gpiod_get_index(dev, "their-claim", 1, GPIOD_IN); + if (!IS_ERR(dummy)) { + dev_err(dev, "Only one other master is supported\n"); + return -EINVAL; + } else if (PTR_ERR(dummy) == -EPROBE_DEFER) { + return -EPROBE_DEFER; + } + + /* Arbitration parameters */ + if (of_property_read_u32(np, "slew-delay-us", &arb->slew_delay_us)) + arb->slew_delay_us = 10; + if (of_property_read_u32(np, "wait-retry-us", &arb->wait_retry_us)) + arb->wait_retry_us = 3000; + if (of_property_read_u32(np, "wait-free-us", &arb->wait_free_us)) + arb->wait_free_us = 50000; + + /* Find our parent */ + parent_np = of_parse_phandle(np, "i2c-parent", 0); + if (!parent_np) { + dev_err(dev, "Cannot parse i2c-parent\n"); + return -EINVAL; + } + muxc->parent = of_get_i2c_adapter_by_node(parent_np); + of_node_put(parent_np); + if (!muxc->parent) { + dev_err(dev, "Cannot find parent bus\n"); + return -EPROBE_DEFER; + } + + /* Actually add the mux adapter */ + ret = i2c_mux_add_adapter(muxc, 0, 0, 0); + if (ret) + i2c_put_adapter(muxc->parent); + + return ret; +} + +static void i2c_arbitrator_remove(struct platform_device *pdev) +{ + struct i2c_mux_core *muxc = platform_get_drvdata(pdev); + + i2c_mux_del_adapters(muxc); + i2c_put_adapter(muxc->parent); +} + +static const struct of_device_id i2c_arbitrator_of_match[] = { + { .compatible = "i2c-arb-gpio-challenge", }, + {}, +}; +MODULE_DEVICE_TABLE(of, i2c_arbitrator_of_match); + +static struct platform_driver i2c_arbitrator_driver = { + .probe = i2c_arbitrator_probe, + .remove_new = i2c_arbitrator_remove, + .driver = { + .name = "i2c-arb-gpio-challenge", + .of_match_table = i2c_arbitrator_of_match, + }, +}; + +module_platform_driver(i2c_arbitrator_driver); + +MODULE_DESCRIPTION("GPIO-based I2C Arbitration"); +MODULE_AUTHOR("Doug Anderson <dianders@chromium.org>"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:i2c-arb-gpio-challenge"); diff --git a/drivers/i2c/muxes/i2c-demux-pinctrl.c b/drivers/i2c/muxes/i2c-demux-pinctrl.c new file mode 100644 index 000000000..9f2e4aa28 --- /dev/null +++ b/drivers/i2c/muxes/i2c-demux-pinctrl.c @@ -0,0 +1,324 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Pinctrl based I2C DeMultiplexer + * + * Copyright (C) 2015-16 by Wolfram Sang, Sang Engineering <wsa@sang-engineering.com> + * Copyright (C) 2015-16 by Renesas Electronics Corporation + * + * See the bindings doc for DTS setup and the sysfs doc for usage information. + * (look for filenames containing 'i2c-demux-pinctrl' in Documentation/) + */ + +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/slab.h> +#include <linux/sysfs.h> + +struct i2c_demux_pinctrl_chan { + struct device_node *parent_np; + struct i2c_adapter *parent_adap; + struct of_changeset chgset; +}; + +struct i2c_demux_pinctrl_priv { + int cur_chan; + int num_chan; + struct device *dev; + const char *bus_name; + struct i2c_adapter cur_adap; + struct i2c_algorithm algo; + struct i2c_demux_pinctrl_chan chan[]; +}; + +static int i2c_demux_master_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + struct i2c_demux_pinctrl_priv *priv = adap->algo_data; + struct i2c_adapter *parent = priv->chan[priv->cur_chan].parent_adap; + + return __i2c_transfer(parent, msgs, num); +} + +static u32 i2c_demux_functionality(struct i2c_adapter *adap) +{ + struct i2c_demux_pinctrl_priv *priv = adap->algo_data; + struct i2c_adapter *parent = priv->chan[priv->cur_chan].parent_adap; + + return parent->algo->functionality(parent); +} + +static int i2c_demux_activate_master(struct i2c_demux_pinctrl_priv *priv, u32 new_chan) +{ + struct i2c_adapter *adap; + struct pinctrl *p; + int ret; + + ret = of_changeset_apply(&priv->chan[new_chan].chgset); + if (ret) + goto err; + + adap = of_get_i2c_adapter_by_node(priv->chan[new_chan].parent_np); + if (!adap) { + ret = -ENODEV; + goto err_with_revert; + } + + /* + * Check if there are pinctrl states at all. Note: we cant' use + * devm_pinctrl_get_select() because we need to distinguish between + * the -ENODEV from devm_pinctrl_get() and pinctrl_lookup_state(). + */ + p = devm_pinctrl_get(adap->dev.parent); + if (IS_ERR(p)) { + ret = PTR_ERR(p); + /* continue if just no pinctrl states (e.g. i2c-gpio), otherwise exit */ + if (ret != -ENODEV) + goto err_with_put; + } else { + /* there are states. check and use them */ + struct pinctrl_state *s = pinctrl_lookup_state(p, priv->bus_name); + + if (IS_ERR(s)) { + ret = PTR_ERR(s); + goto err_with_put; + } + ret = pinctrl_select_state(p, s); + if (ret < 0) + goto err_with_put; + } + + priv->chan[new_chan].parent_adap = adap; + priv->cur_chan = new_chan; + + /* Now fill out current adapter structure. cur_chan must be up to date */ + priv->algo.master_xfer = i2c_demux_master_xfer; + if (adap->algo->master_xfer_atomic) + priv->algo.master_xfer_atomic = i2c_demux_master_xfer; + priv->algo.functionality = i2c_demux_functionality; + + snprintf(priv->cur_adap.name, sizeof(priv->cur_adap.name), + "i2c-demux (master i2c-%d)", i2c_adapter_id(adap)); + priv->cur_adap.owner = THIS_MODULE; + priv->cur_adap.algo = &priv->algo; + priv->cur_adap.algo_data = priv; + priv->cur_adap.dev.parent = &adap->dev; + priv->cur_adap.class = adap->class; + priv->cur_adap.retries = adap->retries; + priv->cur_adap.timeout = adap->timeout; + priv->cur_adap.quirks = adap->quirks; + priv->cur_adap.dev.of_node = priv->dev->of_node; + ret = i2c_add_adapter(&priv->cur_adap); + if (ret < 0) + goto err_with_put; + + return 0; + + err_with_put: + i2c_put_adapter(adap); + err_with_revert: + of_changeset_revert(&priv->chan[new_chan].chgset); + err: + dev_err(priv->dev, "failed to setup demux-adapter %d (%d)\n", new_chan, ret); + priv->cur_chan = -EINVAL; + return ret; +} + +static int i2c_demux_deactivate_master(struct i2c_demux_pinctrl_priv *priv) +{ + int ret, cur = priv->cur_chan; + + if (cur < 0) + return 0; + + i2c_del_adapter(&priv->cur_adap); + i2c_put_adapter(priv->chan[cur].parent_adap); + + ret = of_changeset_revert(&priv->chan[cur].chgset); + + priv->chan[cur].parent_adap = NULL; + priv->cur_chan = -EINVAL; + + return ret; +} + +static int i2c_demux_change_master(struct i2c_demux_pinctrl_priv *priv, u32 new_chan) +{ + int ret; + + if (new_chan == priv->cur_chan) + return 0; + + ret = i2c_demux_deactivate_master(priv); + if (ret) + return ret; + + return i2c_demux_activate_master(priv, new_chan); +} + +static ssize_t available_masters_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct i2c_demux_pinctrl_priv *priv = dev_get_drvdata(dev); + int count = 0, i; + + for (i = 0; i < priv->num_chan && count < PAGE_SIZE; i++) + count += scnprintf(buf + count, PAGE_SIZE - count, "%d:%pOF%c", + i, priv->chan[i].parent_np, + i == priv->num_chan - 1 ? '\n' : ' '); + + return count; +} +static DEVICE_ATTR_RO(available_masters); + +static ssize_t current_master_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct i2c_demux_pinctrl_priv *priv = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", priv->cur_chan); +} + +static ssize_t current_master_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i2c_demux_pinctrl_priv *priv = dev_get_drvdata(dev); + unsigned int val; + int ret; + + ret = kstrtouint(buf, 0, &val); + if (ret < 0) + return ret; + + if (val >= priv->num_chan) + return -EINVAL; + + ret = i2c_demux_change_master(priv, val); + + return ret < 0 ? ret : count; +} +static DEVICE_ATTR_RW(current_master); + +static int i2c_demux_pinctrl_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct i2c_demux_pinctrl_priv *priv; + struct property *props; + int num_chan, i, j, err; + + num_chan = of_count_phandle_with_args(np, "i2c-parent", NULL); + if (num_chan < 2) { + dev_err(&pdev->dev, "Need at least two I2C masters to switch\n"); + return -EINVAL; + } + + priv = devm_kzalloc(&pdev->dev, struct_size(priv, chan, num_chan), + GFP_KERNEL); + + props = devm_kcalloc(&pdev->dev, num_chan, sizeof(*props), GFP_KERNEL); + + if (!priv || !props) + return -ENOMEM; + + err = of_property_read_string(np, "i2c-bus-name", &priv->bus_name); + if (err) + return err; + + for (i = 0; i < num_chan; i++) { + struct device_node *adap_np; + + adap_np = of_parse_phandle(np, "i2c-parent", i); + if (!adap_np) { + dev_err(&pdev->dev, "can't get phandle for parent %d\n", i); + err = -ENOENT; + goto err_rollback; + } + priv->chan[i].parent_np = adap_np; + + props[i].name = devm_kstrdup(&pdev->dev, "status", GFP_KERNEL); + props[i].value = devm_kstrdup(&pdev->dev, "ok", GFP_KERNEL); + if (!props[i].name || !props[i].value) { + err = -ENOMEM; + goto err_rollback; + } + props[i].length = 3; + + of_changeset_init(&priv->chan[i].chgset); + of_changeset_update_property(&priv->chan[i].chgset, adap_np, &props[i]); + } + + priv->num_chan = num_chan; + priv->dev = &pdev->dev; + + platform_set_drvdata(pdev, priv); + + pm_runtime_no_callbacks(&pdev->dev); + + /* switch to first parent as active master */ + i2c_demux_activate_master(priv, 0); + + err = device_create_file(&pdev->dev, &dev_attr_available_masters); + if (err) + goto err_rollback_activation; + + err = device_create_file(&pdev->dev, &dev_attr_current_master); + if (err) + goto err_rollback_available; + + return 0; + +err_rollback_available: + device_remove_file(&pdev->dev, &dev_attr_available_masters); +err_rollback_activation: + i2c_demux_deactivate_master(priv); +err_rollback: + for (j = 0; j < i; j++) { + of_node_put(priv->chan[j].parent_np); + of_changeset_destroy(&priv->chan[j].chgset); + } + + return err; +} + +static void i2c_demux_pinctrl_remove(struct platform_device *pdev) +{ + struct i2c_demux_pinctrl_priv *priv = platform_get_drvdata(pdev); + int i; + + device_remove_file(&pdev->dev, &dev_attr_current_master); + device_remove_file(&pdev->dev, &dev_attr_available_masters); + + i2c_demux_deactivate_master(priv); + + for (i = 0; i < priv->num_chan; i++) { + of_node_put(priv->chan[i].parent_np); + of_changeset_destroy(&priv->chan[i].chgset); + } +} + +static const struct of_device_id i2c_demux_pinctrl_of_match[] = { + { .compatible = "i2c-demux-pinctrl", }, + {}, +}; +MODULE_DEVICE_TABLE(of, i2c_demux_pinctrl_of_match); + +static struct platform_driver i2c_demux_pinctrl_driver = { + .driver = { + .name = "i2c-demux-pinctrl", + .of_match_table = i2c_demux_pinctrl_of_match, + }, + .probe = i2c_demux_pinctrl_probe, + .remove_new = i2c_demux_pinctrl_remove, +}; +module_platform_driver(i2c_demux_pinctrl_driver); + +MODULE_DESCRIPTION("pinctrl-based I2C demux driver"); +MODULE_AUTHOR("Wolfram Sang <wsa@sang-engineering.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:i2c-demux-pinctrl"); diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c new file mode 100644 index 000000000..5ca03bd34 --- /dev/null +++ b/drivers/i2c/muxes/i2c-mux-gpio.c @@ -0,0 +1,258 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * I2C multiplexer using GPIO API + * + * Peter Korsgaard <peter.korsgaard@barco.com> + */ + +#include <linux/i2c.h> +#include <linux/i2c-mux.h> +#include <linux/overflow.h> +#include <linux/platform_data/i2c-mux-gpio.h> +#include <linux/platform_device.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/bits.h> +#include <linux/gpio/consumer.h> +/* FIXME: stop poking around inside gpiolib */ +#include "../../gpio/gpiolib.h" + +struct gpiomux { + struct i2c_mux_gpio_platform_data data; + int ngpios; + struct gpio_desc **gpios; +}; + +static void i2c_mux_gpio_set(const struct gpiomux *mux, unsigned val) +{ + DECLARE_BITMAP(values, BITS_PER_TYPE(val)); + + values[0] = val; + + gpiod_set_array_value_cansleep(mux->ngpios, mux->gpios, NULL, values); +} + +static int i2c_mux_gpio_select(struct i2c_mux_core *muxc, u32 chan) +{ + struct gpiomux *mux = i2c_mux_priv(muxc); + + i2c_mux_gpio_set(mux, chan); + + return 0; +} + +static int i2c_mux_gpio_deselect(struct i2c_mux_core *muxc, u32 chan) +{ + struct gpiomux *mux = i2c_mux_priv(muxc); + + i2c_mux_gpio_set(mux, mux->data.idle); + + return 0; +} + +static int i2c_mux_gpio_probe_fw(struct gpiomux *mux, + struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct fwnode_handle *fwnode = dev_fwnode(dev); + struct device_node *np = dev->of_node; + struct device_node *adapter_np; + struct i2c_adapter *adapter = NULL; + struct fwnode_handle *child; + unsigned *values; + int rc, i = 0; + + if (is_of_node(fwnode)) { + if (!np) + return -ENODEV; + + adapter_np = of_parse_phandle(np, "i2c-parent", 0); + if (!adapter_np) { + dev_err(&pdev->dev, "Cannot parse i2c-parent\n"); + return -ENODEV; + } + adapter = of_find_i2c_adapter_by_node(adapter_np); + of_node_put(adapter_np); + + } else if (is_acpi_node(fwnode)) { + /* + * In ACPI land the mux should be a direct child of the i2c + * bus it muxes. + */ + acpi_handle dev_handle = ACPI_HANDLE(dev->parent); + + adapter = i2c_acpi_find_adapter_by_handle(dev_handle); + } + + if (!adapter) + return -EPROBE_DEFER; + + mux->data.parent = i2c_adapter_id(adapter); + put_device(&adapter->dev); + + mux->data.n_values = device_get_child_node_count(dev); + values = devm_kcalloc(dev, + mux->data.n_values, sizeof(*mux->data.values), + GFP_KERNEL); + if (!values) { + dev_err(dev, "Cannot allocate values array"); + return -ENOMEM; + } + + device_for_each_child_node(dev, child) { + if (is_of_node(child)) { + fwnode_property_read_u32(child, "reg", values + i); + + } else if (is_acpi_node(child)) { + rc = acpi_get_local_address(ACPI_HANDLE_FWNODE(child), values + i); + if (rc) { + fwnode_handle_put(child); + return dev_err_probe(dev, rc, "Cannot get address\n"); + } + } + + i++; + } + mux->data.values = values; + + if (device_property_read_u32(dev, "idle-state", &mux->data.idle)) + mux->data.idle = I2C_MUX_GPIO_NO_IDLE; + + return 0; +} + +static int i2c_mux_gpio_probe(struct platform_device *pdev) +{ + struct i2c_mux_core *muxc; + struct gpiomux *mux; + struct i2c_adapter *parent; + struct i2c_adapter *root; + unsigned initial_state; + int i, ngpios, ret; + + mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL); + if (!mux) + return -ENOMEM; + + if (!dev_get_platdata(&pdev->dev)) { + ret = i2c_mux_gpio_probe_fw(mux, pdev); + if (ret < 0) + return ret; + } else { + memcpy(&mux->data, dev_get_platdata(&pdev->dev), + sizeof(mux->data)); + } + + ngpios = gpiod_count(&pdev->dev, "mux"); + if (ngpios <= 0) { + dev_err(&pdev->dev, "no valid gpios provided\n"); + return ngpios ?: -EINVAL; + } + mux->ngpios = ngpios; + + parent = i2c_get_adapter(mux->data.parent); + if (!parent) + return -EPROBE_DEFER; + + muxc = i2c_mux_alloc(parent, &pdev->dev, mux->data.n_values, + array_size(ngpios, sizeof(*mux->gpios)), 0, + i2c_mux_gpio_select, NULL); + if (!muxc) { + ret = -ENOMEM; + goto alloc_failed; + } + mux->gpios = muxc->priv; + muxc->priv = mux; + + platform_set_drvdata(pdev, muxc); + + root = i2c_root_adapter(&parent->dev); + + muxc->mux_locked = true; + + if (mux->data.idle != I2C_MUX_GPIO_NO_IDLE) { + initial_state = mux->data.idle; + muxc->deselect = i2c_mux_gpio_deselect; + } else { + initial_state = mux->data.values[0]; + } + + for (i = 0; i < ngpios; i++) { + struct device *gpio_dev; + struct gpio_desc *gpiod; + enum gpiod_flags flag; + + if (initial_state & BIT(i)) + flag = GPIOD_OUT_HIGH; + else + flag = GPIOD_OUT_LOW; + gpiod = devm_gpiod_get_index(&pdev->dev, "mux", i, flag); + if (IS_ERR(gpiod)) { + ret = PTR_ERR(gpiod); + goto alloc_failed; + } + + mux->gpios[i] = gpiod; + + if (!muxc->mux_locked) + continue; + + /* FIXME: find a proper way to access the GPIO device */ + gpio_dev = &gpiod->gdev->dev; + muxc->mux_locked = i2c_root_adapter(gpio_dev) == root; + } + + if (muxc->mux_locked) + dev_info(&pdev->dev, "mux-locked i2c mux\n"); + + for (i = 0; i < mux->data.n_values; i++) { + u32 nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0; + unsigned int class = mux->data.classes ? mux->data.classes[i] : 0; + + ret = i2c_mux_add_adapter(muxc, nr, mux->data.values[i], class); + if (ret) + goto add_adapter_failed; + } + + dev_info(&pdev->dev, "%d port mux on %s adapter\n", + mux->data.n_values, parent->name); + + return 0; + +add_adapter_failed: + i2c_mux_del_adapters(muxc); +alloc_failed: + i2c_put_adapter(parent); + + return ret; +} + +static void i2c_mux_gpio_remove(struct platform_device *pdev) +{ + struct i2c_mux_core *muxc = platform_get_drvdata(pdev); + + i2c_mux_del_adapters(muxc); + i2c_put_adapter(muxc->parent); +} + +static const struct of_device_id i2c_mux_gpio_of_match[] = { + { .compatible = "i2c-mux-gpio", }, + {}, +}; +MODULE_DEVICE_TABLE(of, i2c_mux_gpio_of_match); + +static struct platform_driver i2c_mux_gpio_driver = { + .probe = i2c_mux_gpio_probe, + .remove_new = i2c_mux_gpio_remove, + .driver = { + .name = "i2c-mux-gpio", + .of_match_table = i2c_mux_gpio_of_match, + }, +}; + +module_platform_driver(i2c_mux_gpio_driver); + +MODULE_DESCRIPTION("GPIO-based I2C multiplexer driver"); +MODULE_AUTHOR("Peter Korsgaard <peter.korsgaard@barco.com>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:i2c-mux-gpio"); diff --git a/drivers/i2c/muxes/i2c-mux-gpmux.c b/drivers/i2c/muxes/i2c-mux-gpmux.c new file mode 100644 index 000000000..8305661e1 --- /dev/null +++ b/drivers/i2c/muxes/i2c-mux-gpmux.c @@ -0,0 +1,165 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * General Purpose I2C multiplexer + * + * Copyright (C) 2017 Axentia Technologies AB + * + * Author: Peter Rosin <peda@axentia.se> + */ + +#include <linux/i2c.h> +#include <linux/i2c-mux.h> +#include <linux/module.h> +#include <linux/mux/consumer.h> +#include <linux/of.h> +#include <linux/platform_device.h> + +struct mux { + struct mux_control *control; + + bool do_not_deselect; +}; + +static int i2c_mux_select(struct i2c_mux_core *muxc, u32 chan) +{ + struct mux *mux = i2c_mux_priv(muxc); + int ret; + + ret = mux_control_select(mux->control, chan); + mux->do_not_deselect = ret < 0; + + return ret; +} + +static int i2c_mux_deselect(struct i2c_mux_core *muxc, u32 chan) +{ + struct mux *mux = i2c_mux_priv(muxc); + + if (mux->do_not_deselect) + return 0; + + return mux_control_deselect(mux->control); +} + +static struct i2c_adapter *mux_parent_adapter(struct device *dev) +{ + struct device_node *np = dev->of_node; + struct device_node *parent_np; + struct i2c_adapter *parent; + + parent_np = of_parse_phandle(np, "i2c-parent", 0); + if (!parent_np) { + dev_err(dev, "Cannot parse i2c-parent\n"); + return ERR_PTR(-ENODEV); + } + parent = of_get_i2c_adapter_by_node(parent_np); + of_node_put(parent_np); + if (!parent) + return ERR_PTR(-EPROBE_DEFER); + + return parent; +} + +static const struct of_device_id i2c_mux_of_match[] = { + { .compatible = "i2c-mux", }, + {}, +}; +MODULE_DEVICE_TABLE(of, i2c_mux_of_match); + +static int i2c_mux_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct device_node *child; + struct i2c_mux_core *muxc; + struct mux *mux; + struct i2c_adapter *parent; + int children; + int ret; + + if (!np) + return -ENODEV; + + mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL); + if (!mux) + return -ENOMEM; + + mux->control = devm_mux_control_get(dev, NULL); + if (IS_ERR(mux->control)) + return dev_err_probe(dev, PTR_ERR(mux->control), + "failed to get control-mux\n"); + + parent = mux_parent_adapter(dev); + if (IS_ERR(parent)) + return dev_err_probe(dev, PTR_ERR(parent), + "failed to get i2c-parent adapter\n"); + + children = of_get_child_count(np); + + muxc = i2c_mux_alloc(parent, dev, children, 0, 0, + i2c_mux_select, i2c_mux_deselect); + if (!muxc) { + ret = -ENOMEM; + goto err_parent; + } + muxc->priv = mux; + + platform_set_drvdata(pdev, muxc); + + muxc->mux_locked = of_property_read_bool(np, "mux-locked"); + + for_each_child_of_node(np, child) { + u32 chan; + + ret = of_property_read_u32(child, "reg", &chan); + if (ret < 0) { + dev_err(dev, "no reg property for node '%pOFn'\n", + child); + goto err_children; + } + + if (chan >= mux_control_states(mux->control)) { + dev_err(dev, "invalid reg %u\n", chan); + ret = -EINVAL; + goto err_children; + } + + ret = i2c_mux_add_adapter(muxc, 0, chan, 0); + if (ret) + goto err_children; + } + + dev_info(dev, "%d-port mux on %s adapter\n", children, parent->name); + + return 0; + +err_children: + of_node_put(child); + i2c_mux_del_adapters(muxc); +err_parent: + i2c_put_adapter(parent); + + return ret; +} + +static void i2c_mux_remove(struct platform_device *pdev) +{ + struct i2c_mux_core *muxc = platform_get_drvdata(pdev); + + i2c_mux_del_adapters(muxc); + i2c_put_adapter(muxc->parent); +} + +static struct platform_driver i2c_mux_driver = { + .probe = i2c_mux_probe, + .remove_new = i2c_mux_remove, + .driver = { + .name = "i2c-mux-gpmux", + .of_match_table = i2c_mux_of_match, + }, +}; +module_platform_driver(i2c_mux_driver); + +MODULE_DESCRIPTION("General Purpose I2C multiplexer driver"); +MODULE_AUTHOR("Peter Rosin <peda@axentia.se>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/muxes/i2c-mux-ltc4306.c b/drivers/i2c/muxes/i2c-mux-ltc4306.c new file mode 100644 index 000000000..23766d853 --- /dev/null +++ b/drivers/i2c/muxes/i2c-mux-ltc4306.c @@ -0,0 +1,317 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Linear Technology LTC4306 and LTC4305 I2C multiplexer/switch + * + * Copyright (C) 2017 Analog Devices Inc. + * + * Based on: i2c-mux-pca954x.c + * + * Datasheet: http://cds.linear.com/docs/en/datasheet/4306.pdf + */ + +#include <linux/gpio/consumer.h> +#include <linux/gpio/driver.h> +#include <linux/i2c-mux.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/property.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#define LTC4305_MAX_NCHANS 2 +#define LTC4306_MAX_NCHANS 4 + +#define LTC_REG_STATUS 0x0 +#define LTC_REG_CONFIG 0x1 +#define LTC_REG_MODE 0x2 +#define LTC_REG_SWITCH 0x3 + +#define LTC_DOWNSTREAM_ACCL_EN BIT(6) +#define LTC_UPSTREAM_ACCL_EN BIT(7) + +#define LTC_GPIO_ALL_INPUT 0xC0 +#define LTC_SWITCH_MASK 0xF0 + +enum ltc_type { + ltc_4305, + ltc_4306, +}; + +struct chip_desc { + u8 nchans; + u8 num_gpios; +}; + +struct ltc4306 { + struct regmap *regmap; + struct gpio_chip gpiochip; + const struct chip_desc *chip; +}; + +static const struct chip_desc chips[] = { + [ltc_4305] = { + .nchans = LTC4305_MAX_NCHANS, + }, + [ltc_4306] = { + .nchans = LTC4306_MAX_NCHANS, + .num_gpios = 2, + }, +}; + +static bool ltc4306_is_volatile_reg(struct device *dev, unsigned int reg) +{ + return reg == LTC_REG_CONFIG; +} + +static const struct regmap_config ltc4306_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = LTC_REG_SWITCH, + .volatile_reg = ltc4306_is_volatile_reg, + .cache_type = REGCACHE_FLAT, +}; + +static int ltc4306_gpio_get(struct gpio_chip *chip, unsigned int offset) +{ + struct ltc4306 *data = gpiochip_get_data(chip); + unsigned int val; + int ret; + + ret = regmap_read(data->regmap, LTC_REG_CONFIG, &val); + if (ret < 0) + return ret; + + return !!(val & BIT(1 - offset)); +} + +static void ltc4306_gpio_set(struct gpio_chip *chip, unsigned int offset, + int value) +{ + struct ltc4306 *data = gpiochip_get_data(chip); + + regmap_update_bits(data->regmap, LTC_REG_CONFIG, BIT(5 - offset), + value ? BIT(5 - offset) : 0); +} + +static int ltc4306_gpio_get_direction(struct gpio_chip *chip, + unsigned int offset) +{ + struct ltc4306 *data = gpiochip_get_data(chip); + unsigned int val; + int ret; + + ret = regmap_read(data->regmap, LTC_REG_MODE, &val); + if (ret < 0) + return ret; + + return !!(val & BIT(7 - offset)); +} + +static int ltc4306_gpio_direction_input(struct gpio_chip *chip, + unsigned int offset) +{ + struct ltc4306 *data = gpiochip_get_data(chip); + + return regmap_update_bits(data->regmap, LTC_REG_MODE, + BIT(7 - offset), BIT(7 - offset)); +} + +static int ltc4306_gpio_direction_output(struct gpio_chip *chip, + unsigned int offset, int value) +{ + struct ltc4306 *data = gpiochip_get_data(chip); + + ltc4306_gpio_set(chip, offset, value); + return regmap_update_bits(data->regmap, LTC_REG_MODE, + BIT(7 - offset), 0); +} + +static int ltc4306_gpio_set_config(struct gpio_chip *chip, + unsigned int offset, unsigned long config) +{ + struct ltc4306 *data = gpiochip_get_data(chip); + unsigned int val; + + switch (pinconf_to_config_param(config)) { + case PIN_CONFIG_DRIVE_OPEN_DRAIN: + val = 0; + break; + case PIN_CONFIG_DRIVE_PUSH_PULL: + val = BIT(4 - offset); + break; + default: + return -ENOTSUPP; + } + + return regmap_update_bits(data->regmap, LTC_REG_MODE, + BIT(4 - offset), val); +} + +static int ltc4306_gpio_init(struct ltc4306 *data) +{ + struct device *dev = regmap_get_device(data->regmap); + + if (!data->chip->num_gpios) + return 0; + + data->gpiochip.label = dev_name(dev); + data->gpiochip.base = -1; + data->gpiochip.ngpio = data->chip->num_gpios; + data->gpiochip.parent = dev; + data->gpiochip.can_sleep = true; + data->gpiochip.get_direction = ltc4306_gpio_get_direction; + data->gpiochip.direction_input = ltc4306_gpio_direction_input; + data->gpiochip.direction_output = ltc4306_gpio_direction_output; + data->gpiochip.get = ltc4306_gpio_get; + data->gpiochip.set = ltc4306_gpio_set; + data->gpiochip.set_config = ltc4306_gpio_set_config; + data->gpiochip.owner = THIS_MODULE; + + /* gpiolib assumes all GPIOs default input */ + regmap_write(data->regmap, LTC_REG_MODE, LTC_GPIO_ALL_INPUT); + + return devm_gpiochip_add_data(dev, &data->gpiochip, data); +} + +static int ltc4306_select_mux(struct i2c_mux_core *muxc, u32 chan) +{ + struct ltc4306 *data = i2c_mux_priv(muxc); + + return regmap_update_bits(data->regmap, LTC_REG_SWITCH, + LTC_SWITCH_MASK, BIT(7 - chan)); +} + +static int ltc4306_deselect_mux(struct i2c_mux_core *muxc, u32 chan) +{ + struct ltc4306 *data = i2c_mux_priv(muxc); + + return regmap_update_bits(data->regmap, LTC_REG_SWITCH, + LTC_SWITCH_MASK, 0); +} + +static const struct i2c_device_id ltc4306_id[] = { + { "ltc4305", ltc_4305 }, + { "ltc4306", ltc_4306 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ltc4306_id); + +static const struct of_device_id ltc4306_of_match[] = { + { .compatible = "lltc,ltc4305", .data = &chips[ltc_4305] }, + { .compatible = "lltc,ltc4306", .data = &chips[ltc_4306] }, + { } +}; +MODULE_DEVICE_TABLE(of, ltc4306_of_match); + +static int ltc4306_probe(struct i2c_client *client) +{ + struct i2c_adapter *adap = client->adapter; + const struct chip_desc *chip; + struct i2c_mux_core *muxc; + struct ltc4306 *data; + struct gpio_desc *gpio; + bool idle_disc; + unsigned int val = 0; + int num, ret; + + chip = of_device_get_match_data(&client->dev); + + if (!chip) + chip = &chips[i2c_match_id(ltc4306_id, client)->driver_data]; + + idle_disc = device_property_read_bool(&client->dev, + "i2c-mux-idle-disconnect"); + + muxc = i2c_mux_alloc(adap, &client->dev, + chip->nchans, sizeof(*data), + I2C_MUX_LOCKED, ltc4306_select_mux, + idle_disc ? ltc4306_deselect_mux : NULL); + if (!muxc) + return -ENOMEM; + data = i2c_mux_priv(muxc); + data->chip = chip; + + i2c_set_clientdata(client, muxc); + + data->regmap = devm_regmap_init_i2c(client, <c4306_regmap_config); + if (IS_ERR(data->regmap)) { + ret = PTR_ERR(data->regmap); + dev_err(&client->dev, "Failed to allocate register map: %d\n", + ret); + return ret; + } + + /* Reset and enable the mux if an enable GPIO is specified. */ + gpio = devm_gpiod_get_optional(&client->dev, "enable", GPIOD_OUT_LOW); + if (IS_ERR(gpio)) + return PTR_ERR(gpio); + + if (gpio) { + udelay(1); + gpiod_set_value(gpio, 1); + } + + /* + * Write the mux register at addr to verify + * that the mux is in fact present. This also + * initializes the mux to disconnected state. + */ + if (regmap_write(data->regmap, LTC_REG_SWITCH, 0) < 0) { + dev_warn(&client->dev, "probe failed\n"); + return -ENODEV; + } + + if (device_property_read_bool(&client->dev, + "ltc,downstream-accelerators-enable")) + val |= LTC_DOWNSTREAM_ACCL_EN; + + if (device_property_read_bool(&client->dev, + "ltc,upstream-accelerators-enable")) + val |= LTC_UPSTREAM_ACCL_EN; + + if (regmap_write(data->regmap, LTC_REG_CONFIG, val) < 0) + return -ENODEV; + + ret = ltc4306_gpio_init(data); + if (ret < 0) + return ret; + + /* Now create an adapter for each channel */ + for (num = 0; num < chip->nchans; num++) { + ret = i2c_mux_add_adapter(muxc, 0, num, 0); + if (ret) { + i2c_mux_del_adapters(muxc); + return ret; + } + } + + dev_info(&client->dev, + "registered %d multiplexed busses for I2C switch %s\n", + num, client->name); + + return 0; +} + +static void ltc4306_remove(struct i2c_client *client) +{ + struct i2c_mux_core *muxc = i2c_get_clientdata(client); + + i2c_mux_del_adapters(muxc); +} + +static struct i2c_driver ltc4306_driver = { + .driver = { + .name = "ltc4306", + .of_match_table = of_match_ptr(ltc4306_of_match), + }, + .probe = ltc4306_probe, + .remove = ltc4306_remove, + .id_table = ltc4306_id, +}; + +module_i2c_driver(ltc4306_driver); + +MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>"); +MODULE_DESCRIPTION("Linear Technology LTC4306, LTC4305 I2C mux/switch driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/muxes/i2c-mux-mlxcpld.c b/drivers/i2c/muxes/i2c-mux-mlxcpld.c new file mode 100644 index 000000000..3dda00f1d --- /dev/null +++ b/drivers/i2c/muxes/i2c-mux-mlxcpld.c @@ -0,0 +1,193 @@ +// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 +/* + * Mellanox i2c mux driver + * + * Copyright (C) 2016-2020 Mellanox Technologies + */ + +#include <linux/device.h> +#include <linux/i2c.h> +#include <linux/i2c-mux.h> +#include <linux/io.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/platform_data/mlxcpld.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +/* mlxcpld_mux - mux control structure: + * @last_val - last selected register value or -1 if mux deselected + * @client - I2C device client + * @pdata: platform data + */ +struct mlxcpld_mux { + int last_val; + struct i2c_client *client; + struct mlxcpld_mux_plat_data pdata; +}; + +/* MUX logic description. + * Driver can support different mux control logic, according to CPLD + * implementation. + * + * Connectivity schema. + * + * i2c-mlxcpld Digital Analog + * driver + * *--------* * -> mux1 (virt bus2) -> mux -> | + * | I2CLPC | i2c physical * -> mux2 (virt bus3) -> mux -> | + * | bridge | bus 1 *---------* | + * | logic |---------------------> * mux reg * | + * | in CPLD| *---------* | + * *--------* i2c-mux-mlxpcld ^ * -> muxn (virt busn) -> mux -> | + * | driver | | + * | *---------------* | Devices + * | * CPLD (i2c bus)* select | + * | * registers for *--------* + * | * mux selection * deselect + * | *---------------* + * | | + * <--------> <-----------> + * i2c cntrl Board cntrl reg + * reg space space (mux select, + * IO, LED, WD, info) + * + */ + +/* Write to mux register. Don't use i2c_transfer() and i2c_smbus_xfer() + * for this as they will try to lock adapter a second time. + */ +static int mlxcpld_mux_reg_write(struct i2c_adapter *adap, + struct mlxcpld_mux *mux, u32 val) +{ + struct i2c_client *client = mux->client; + union i2c_smbus_data data; + struct i2c_msg msg; + u8 buf[3]; + + switch (mux->pdata.reg_size) { + case 1: + data.byte = val; + return __i2c_smbus_xfer(adap, client->addr, client->flags, + I2C_SMBUS_WRITE, mux->pdata.sel_reg_addr, + I2C_SMBUS_BYTE_DATA, &data); + case 2: + buf[0] = mux->pdata.sel_reg_addr >> 8; + buf[1] = mux->pdata.sel_reg_addr; + buf[2] = val; + msg.addr = client->addr; + msg.buf = buf; + msg.len = mux->pdata.reg_size + 1; + msg.flags = 0; + return __i2c_transfer(adap, &msg, 1); + default: + return -EINVAL; + } +} + +static int mlxcpld_mux_select_chan(struct i2c_mux_core *muxc, u32 chan) +{ + struct mlxcpld_mux *mux = i2c_mux_priv(muxc); + u32 regval = chan; + int err = 0; + + if (mux->pdata.reg_size == 1) + regval += 1; + + /* Only select the channel if its different from the last channel */ + if (mux->last_val != regval) { + err = mlxcpld_mux_reg_write(muxc->parent, mux, regval); + mux->last_val = err < 0 ? -1 : regval; + } + + return err; +} + +static int mlxcpld_mux_deselect(struct i2c_mux_core *muxc, u32 chan) +{ + struct mlxcpld_mux *mux = i2c_mux_priv(muxc); + + /* Deselect active channel */ + mux->last_val = -1; + + return mlxcpld_mux_reg_write(muxc->parent, mux, 0); +} + +/* Probe/reomove functions */ +static int mlxcpld_mux_probe(struct platform_device *pdev) +{ + struct mlxcpld_mux_plat_data *pdata = dev_get_platdata(&pdev->dev); + struct i2c_client *client = to_i2c_client(pdev->dev.parent); + struct i2c_mux_core *muxc; + struct mlxcpld_mux *data; + int num, err; + u32 func; + + if (!pdata) + return -EINVAL; + + switch (pdata->reg_size) { + case 1: + func = I2C_FUNC_SMBUS_WRITE_BYTE_DATA; + break; + case 2: + func = I2C_FUNC_I2C; + break; + default: + return -EINVAL; + } + + if (!i2c_check_functionality(client->adapter, func)) + return -ENODEV; + + muxc = i2c_mux_alloc(client->adapter, &pdev->dev, pdata->num_adaps, + sizeof(*data), 0, mlxcpld_mux_select_chan, + mlxcpld_mux_deselect); + if (!muxc) + return -ENOMEM; + + platform_set_drvdata(pdev, muxc); + data = i2c_mux_priv(muxc); + data->client = client; + memcpy(&data->pdata, pdata, sizeof(*pdata)); + data->last_val = -1; /* force the first selection */ + + /* Create an adapter for each channel. */ + for (num = 0; num < pdata->num_adaps; num++) { + err = i2c_mux_add_adapter(muxc, 0, pdata->chan_ids[num], 0); + if (err) + goto virt_reg_failed; + } + + /* Notify caller when all channels' adapters are created. */ + if (pdata->completion_notify) + pdata->completion_notify(pdata->handle, muxc->parent, muxc->adapter); + + return 0; + +virt_reg_failed: + i2c_mux_del_adapters(muxc); + return err; +} + +static void mlxcpld_mux_remove(struct platform_device *pdev) +{ + struct i2c_mux_core *muxc = platform_get_drvdata(pdev); + + i2c_mux_del_adapters(muxc); +} + +static struct platform_driver mlxcpld_mux_driver = { + .driver = { + .name = "i2c-mux-mlxcpld", + }, + .probe = mlxcpld_mux_probe, + .remove_new = mlxcpld_mux_remove, +}; + +module_platform_driver(mlxcpld_mux_driver); + +MODULE_AUTHOR("Michael Shych (michaels@mellanox.com)"); +MODULE_DESCRIPTION("Mellanox I2C-CPLD-MUX driver"); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_ALIAS("platform:i2c-mux-mlxcpld"); diff --git a/drivers/i2c/muxes/i2c-mux-pca9541.c b/drivers/i2c/muxes/i2c-mux-pca9541.c new file mode 100644 index 000000000..ce0fb6924 --- /dev/null +++ b/drivers/i2c/muxes/i2c-mux-pca9541.c @@ -0,0 +1,348 @@ +/* + * I2C multiplexer driver for PCA9541 bus master selector + * + * Copyright (c) 2010 Ericsson AB. + * + * Author: Guenter Roeck <linux@roeck-us.net> + * + * Derived from: + * pca954x.c + * + * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it> + * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/bitops.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/i2c.h> +#include <linux/i2c-mux.h> +#include <linux/jiffies.h> +#include <linux/module.h> +#include <linux/slab.h> + +/* + * The PCA9541 is a bus master selector. It supports two I2C masters connected + * to a single slave bus. + * + * Before each bus transaction, a master has to acquire bus ownership. After the + * transaction is complete, bus ownership has to be released. This fits well + * into the I2C multiplexer framework, which provides select and release + * functions for this purpose. For this reason, this driver is modeled as + * single-channel I2C bus multiplexer. + * + * This driver assumes that the two bus masters are controlled by two different + * hosts. If a single host controls both masters, platform code has to ensure + * that only one of the masters is instantiated at any given time. + */ + +#define PCA9541_CONTROL 0x01 +#define PCA9541_ISTAT 0x02 + +#define PCA9541_CTL_MYBUS BIT(0) +#define PCA9541_CTL_NMYBUS BIT(1) +#define PCA9541_CTL_BUSON BIT(2) +#define PCA9541_CTL_NBUSON BIT(3) +#define PCA9541_CTL_BUSINIT BIT(4) +#define PCA9541_CTL_TESTON BIT(6) +#define PCA9541_CTL_NTESTON BIT(7) + +#define PCA9541_ISTAT_INTIN BIT(0) +#define PCA9541_ISTAT_BUSINIT BIT(1) +#define PCA9541_ISTAT_BUSOK BIT(2) +#define PCA9541_ISTAT_BUSLOST BIT(3) +#define PCA9541_ISTAT_MYTEST BIT(6) +#define PCA9541_ISTAT_NMYTEST BIT(7) + +#define BUSON (PCA9541_CTL_BUSON | PCA9541_CTL_NBUSON) +#define MYBUS (PCA9541_CTL_MYBUS | PCA9541_CTL_NMYBUS) +#define mybus(x) (!((x) & MYBUS) || ((x) & MYBUS) == MYBUS) +#define busoff(x) (!((x) & BUSON) || ((x) & BUSON) == BUSON) + +/* arbitration timeouts, in jiffies */ +#define ARB_TIMEOUT (HZ / 8) /* 125 ms until forcing bus ownership */ +#define ARB2_TIMEOUT (HZ / 4) /* 250 ms until acquisition failure */ + +/* arbitration retry delays, in us */ +#define SELECT_DELAY_SHORT 50 +#define SELECT_DELAY_LONG 1000 + +struct pca9541 { + struct i2c_client *client; + unsigned long select_timeout; + unsigned long arb_timeout; +}; + +static const struct i2c_device_id pca9541_id[] = { + {"pca9541", 0}, + {} +}; + +MODULE_DEVICE_TABLE(i2c, pca9541_id); + +#ifdef CONFIG_OF +static const struct of_device_id pca9541_of_match[] = { + { .compatible = "nxp,pca9541" }, + {} +}; +MODULE_DEVICE_TABLE(of, pca9541_of_match); +#endif + +/* + * Write to chip register. Don't use i2c_transfer()/i2c_smbus_xfer() + * as they will try to lock the adapter a second time. + */ +static int pca9541_reg_write(struct i2c_client *client, u8 command, u8 val) +{ + struct i2c_adapter *adap = client->adapter; + union i2c_smbus_data data = { .byte = val }; + + return __i2c_smbus_xfer(adap, client->addr, client->flags, + I2C_SMBUS_WRITE, command, + I2C_SMBUS_BYTE_DATA, &data); +} + +/* + * Read from chip register. Don't use i2c_transfer()/i2c_smbus_xfer() + * as they will try to lock adapter a second time. + */ +static int pca9541_reg_read(struct i2c_client *client, u8 command) +{ + struct i2c_adapter *adap = client->adapter; + union i2c_smbus_data data; + int ret; + + ret = __i2c_smbus_xfer(adap, client->addr, client->flags, + I2C_SMBUS_READ, command, + I2C_SMBUS_BYTE_DATA, &data); + + return ret ?: data.byte; +} + +/* + * Arbitration management functions + */ + +/* Release bus. Also reset NTESTON and BUSINIT if it was set. */ +static void pca9541_release_bus(struct i2c_client *client) +{ + int reg; + + reg = pca9541_reg_read(client, PCA9541_CONTROL); + if (reg >= 0 && !busoff(reg) && mybus(reg)) + pca9541_reg_write(client, PCA9541_CONTROL, + (reg & PCA9541_CTL_NBUSON) >> 1); +} + +/* + * Arbitration is defined as a two-step process. A bus master can only activate + * the slave bus if it owns it; otherwise it has to request ownership first. + * This multi-step process ensures that access contention is resolved + * gracefully. + * + * Bus Ownership Other master Action + * state requested access + * ---------------------------------------------------- + * off - yes wait for arbitration timeout or + * for other master to drop request + * off no no take ownership + * off yes no turn on bus + * on yes - done + * on no - wait for arbitration timeout or + * for other master to release bus + * + * The main contention point occurs if the slave bus is off and both masters + * request ownership at the same time. In this case, one master will turn on + * the slave bus, believing that it owns it. The other master will request + * bus ownership. Result is that the bus is turned on, and master which did + * _not_ own the slave bus before ends up owning it. + */ + +/* Control commands per PCA9541 datasheet */ +static const u8 pca9541_control[16] = { + 4, 0, 1, 5, 4, 4, 5, 5, 0, 0, 1, 1, 0, 4, 5, 1 +}; + +/* + * Channel arbitration + * + * Return values: + * <0: error + * 0 : bus not acquired + * 1 : bus acquired + */ +static int pca9541_arbitrate(struct i2c_client *client) +{ + struct i2c_mux_core *muxc = i2c_get_clientdata(client); + struct pca9541 *data = i2c_mux_priv(muxc); + int reg; + + reg = pca9541_reg_read(client, PCA9541_CONTROL); + if (reg < 0) + return reg; + + if (busoff(reg)) { + int istat; + /* + * Bus is off. Request ownership or turn it on unless + * other master requested ownership. + */ + istat = pca9541_reg_read(client, PCA9541_ISTAT); + if (!(istat & PCA9541_ISTAT_NMYTEST) + || time_is_before_eq_jiffies(data->arb_timeout)) { + /* + * Other master did not request ownership, + * or arbitration timeout expired. Take the bus. + */ + pca9541_reg_write(client, + PCA9541_CONTROL, + pca9541_control[reg & 0x0f] + | PCA9541_CTL_NTESTON); + data->select_timeout = SELECT_DELAY_SHORT; + } else { + /* + * Other master requested ownership. + * Set extra long timeout to give it time to acquire it. + */ + data->select_timeout = SELECT_DELAY_LONG * 2; + } + } else if (mybus(reg)) { + /* + * Bus is on, and we own it. We are done with acquisition. + * Reset NTESTON and BUSINIT, then return success. + */ + if (reg & (PCA9541_CTL_NTESTON | PCA9541_CTL_BUSINIT)) + pca9541_reg_write(client, + PCA9541_CONTROL, + reg & ~(PCA9541_CTL_NTESTON + | PCA9541_CTL_BUSINIT)); + return 1; + } else { + /* + * Other master owns the bus. + * If arbitration timeout has expired, force ownership. + * Otherwise request it. + */ + data->select_timeout = SELECT_DELAY_LONG; + if (time_is_before_eq_jiffies(data->arb_timeout)) { + /* Time is up, take the bus and reset it. */ + pca9541_reg_write(client, + PCA9541_CONTROL, + pca9541_control[reg & 0x0f] + | PCA9541_CTL_BUSINIT + | PCA9541_CTL_NTESTON); + } else { + /* Request bus ownership if needed */ + if (!(reg & PCA9541_CTL_NTESTON)) + pca9541_reg_write(client, + PCA9541_CONTROL, + reg | PCA9541_CTL_NTESTON); + } + } + return 0; +} + +static int pca9541_select_chan(struct i2c_mux_core *muxc, u32 chan) +{ + struct pca9541 *data = i2c_mux_priv(muxc); + struct i2c_client *client = data->client; + int ret; + unsigned long timeout = jiffies + ARB2_TIMEOUT; + /* give up after this time */ + + data->arb_timeout = jiffies + ARB_TIMEOUT; + /* force bus ownership after this time */ + + do { + ret = pca9541_arbitrate(client); + if (ret) + return ret < 0 ? ret : 0; + + if (data->select_timeout == SELECT_DELAY_SHORT) + udelay(data->select_timeout); + else + msleep(data->select_timeout / 1000); + } while (time_is_after_eq_jiffies(timeout)); + + return -ETIMEDOUT; +} + +static int pca9541_release_chan(struct i2c_mux_core *muxc, u32 chan) +{ + struct pca9541 *data = i2c_mux_priv(muxc); + struct i2c_client *client = data->client; + + pca9541_release_bus(client); + return 0; +} + +/* + * I2C init/probing/exit functions + */ +static int pca9541_probe(struct i2c_client *client) +{ + struct i2c_adapter *adap = client->adapter; + struct i2c_mux_core *muxc; + struct pca9541 *data; + int ret; + + if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE_DATA)) + return -ENODEV; + + /* + * I2C accesses are unprotected here. + * We have to lock the I2C segment before releasing the bus. + */ + i2c_lock_bus(adap, I2C_LOCK_SEGMENT); + pca9541_release_bus(client); + i2c_unlock_bus(adap, I2C_LOCK_SEGMENT); + + /* Create mux adapter */ + + muxc = i2c_mux_alloc(adap, &client->dev, 1, sizeof(*data), + I2C_MUX_ARBITRATOR, + pca9541_select_chan, pca9541_release_chan); + if (!muxc) + return -ENOMEM; + + data = i2c_mux_priv(muxc); + data->client = client; + + i2c_set_clientdata(client, muxc); + + ret = i2c_mux_add_adapter(muxc, 0, 0, 0); + if (ret) + return ret; + + dev_info(&client->dev, "registered master selector for I2C %s\n", + client->name); + + return 0; +} + +static void pca9541_remove(struct i2c_client *client) +{ + struct i2c_mux_core *muxc = i2c_get_clientdata(client); + + i2c_mux_del_adapters(muxc); +} + +static struct i2c_driver pca9541_driver = { + .driver = { + .name = "pca9541", + .of_match_table = of_match_ptr(pca9541_of_match), + }, + .probe = pca9541_probe, + .remove = pca9541_remove, + .id_table = pca9541_id, +}; + +module_i2c_driver(pca9541_driver); + +MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>"); +MODULE_DESCRIPTION("PCA9541 I2C master selector driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c new file mode 100644 index 000000000..221906210 --- /dev/null +++ b/drivers/i2c/muxes/i2c-mux-pca954x.c @@ -0,0 +1,647 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * I2C multiplexer + * + * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it> + * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it> + * + * This module supports the PCA954x and PCA984x series of I2C multiplexer/switch + * chips made by NXP Semiconductors. + * This includes the: + * PCA9540, PCA9542, PCA9543, PCA9544, PCA9545, PCA9546, PCA9547, + * PCA9548, PCA9846, PCA9847, PCA9848 and PCA9849. + * + * It's also compatible to Maxims MAX735x I2C switch chips, which are controlled + * as the NXP PCA9548 and the MAX736x chips that act like the PCA9544. + * + * This includes the: + * MAX7356, MAX7357, MAX7358, MAX7367, MAX7368 and MAX7369 + * + * These chips are all controlled via the I2C bus itself, and all have a + * single 8-bit register. The upstream "parent" bus fans out to two, + * four, or eight downstream busses or channels; which of these + * are selected is determined by the chip type and register contents. A + * mux can select only one sub-bus at a time; a switch can select any + * combination simultaneously. + * + * Based on: + * pca954x.c from Kumar Gala <galak@kernel.crashing.org> + * Copyright (C) 2006 + * + * Based on: + * pca954x.c from Ken Harrenstien + * Copyright (C) 2004 Google, Inc. (Ken Harrenstien) + * + * Based on: + * i2c-virtual_cb.c from Brian Kuschak <bkuschak@yahoo.com> + * and + * pca9540.c from Jean Delvare <jdelvare@suse.de>. + */ + +#include <linux/device.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/i2c-mux.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/module.h> +#include <linux/pm.h> +#include <linux/property.h> +#include <linux/regulator/consumer.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <dt-bindings/mux/mux.h> + +#define PCA954X_MAX_NCHANS 8 + +#define PCA954X_IRQ_OFFSET 4 + +enum pca_type { + max_7356, + max_7357, + max_7358, + max_7367, + max_7368, + max_7369, + pca_9540, + pca_9542, + pca_9543, + pca_9544, + pca_9545, + pca_9546, + pca_9547, + pca_9548, + pca_9846, + pca_9847, + pca_9848, + pca_9849, +}; + +struct chip_desc { + u8 nchans; + u8 enable; /* used for muxes only */ + u8 has_irq; + enum muxtype { + pca954x_ismux = 0, + pca954x_isswi + } muxtype; + struct i2c_device_identity id; +}; + +struct pca954x { + const struct chip_desc *chip; + + u8 last_chan; /* last register value */ + /* MUX_IDLE_AS_IS, MUX_IDLE_DISCONNECT or >= 0 for channel */ + s32 idle_state; + + struct i2c_client *client; + + struct irq_domain *irq; + unsigned int irq_mask; + raw_spinlock_t lock; + struct regulator *supply; +}; + +/* Provide specs for the MAX735x, PCA954x and PCA984x types we know about */ +static const struct chip_desc chips[] = { + [max_7356] = { + .nchans = 8, + .muxtype = pca954x_isswi, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, + [max_7357] = { + .nchans = 8, + .muxtype = pca954x_isswi, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + /* + * No interrupt controller support. The interrupt + * provides information about stuck channels. + */ + }, + [max_7358] = { + .nchans = 8, + .muxtype = pca954x_isswi, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + /* + * No interrupt controller support. The interrupt + * provides information about stuck channels. + */ + }, + [max_7367] = { + .nchans = 4, + .muxtype = pca954x_isswi, + .has_irq = 1, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, + [max_7368] = { + .nchans = 4, + .muxtype = pca954x_isswi, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, + [max_7369] = { + .nchans = 4, + .enable = 0x4, + .muxtype = pca954x_ismux, + .has_irq = 1, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, + [pca_9540] = { + .nchans = 2, + .enable = 0x4, + .muxtype = pca954x_ismux, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, + [pca_9542] = { + .nchans = 2, + .enable = 0x4, + .has_irq = 1, + .muxtype = pca954x_ismux, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, + [pca_9543] = { + .nchans = 2, + .has_irq = 1, + .muxtype = pca954x_isswi, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, + [pca_9544] = { + .nchans = 4, + .enable = 0x4, + .has_irq = 1, + .muxtype = pca954x_ismux, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, + [pca_9545] = { + .nchans = 4, + .has_irq = 1, + .muxtype = pca954x_isswi, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, + [pca_9546] = { + .nchans = 4, + .muxtype = pca954x_isswi, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, + [pca_9547] = { + .nchans = 8, + .enable = 0x8, + .muxtype = pca954x_ismux, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, + [pca_9548] = { + .nchans = 8, + .muxtype = pca954x_isswi, + .id = { .manufacturer_id = I2C_DEVICE_ID_NONE }, + }, + [pca_9846] = { + .nchans = 4, + .muxtype = pca954x_isswi, + .id = { + .manufacturer_id = I2C_DEVICE_ID_NXP_SEMICONDUCTORS, + .part_id = 0x10b, + }, + }, + [pca_9847] = { + .nchans = 8, + .enable = 0x8, + .muxtype = pca954x_ismux, + .id = { + .manufacturer_id = I2C_DEVICE_ID_NXP_SEMICONDUCTORS, + .part_id = 0x108, + }, + }, + [pca_9848] = { + .nchans = 8, + .muxtype = pca954x_isswi, + .id = { + .manufacturer_id = I2C_DEVICE_ID_NXP_SEMICONDUCTORS, + .part_id = 0x10a, + }, + }, + [pca_9849] = { + .nchans = 4, + .enable = 0x4, + .muxtype = pca954x_ismux, + .id = { + .manufacturer_id = I2C_DEVICE_ID_NXP_SEMICONDUCTORS, + .part_id = 0x109, + }, + }, +}; + +static const struct i2c_device_id pca954x_id[] = { + { "max7356", max_7356 }, + { "max7357", max_7357 }, + { "max7358", max_7358 }, + { "max7367", max_7367 }, + { "max7368", max_7368 }, + { "max7369", max_7369 }, + { "pca9540", pca_9540 }, + { "pca9542", pca_9542 }, + { "pca9543", pca_9543 }, + { "pca9544", pca_9544 }, + { "pca9545", pca_9545 }, + { "pca9546", pca_9546 }, + { "pca9547", pca_9547 }, + { "pca9548", pca_9548 }, + { "pca9846", pca_9846 }, + { "pca9847", pca_9847 }, + { "pca9848", pca_9848 }, + { "pca9849", pca_9849 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, pca954x_id); + +static const struct of_device_id pca954x_of_match[] = { + { .compatible = "maxim,max7356", .data = &chips[max_7356] }, + { .compatible = "maxim,max7357", .data = &chips[max_7357] }, + { .compatible = "maxim,max7358", .data = &chips[max_7358] }, + { .compatible = "maxim,max7367", .data = &chips[max_7367] }, + { .compatible = "maxim,max7368", .data = &chips[max_7368] }, + { .compatible = "maxim,max7369", .data = &chips[max_7369] }, + { .compatible = "nxp,pca9540", .data = &chips[pca_9540] }, + { .compatible = "nxp,pca9542", .data = &chips[pca_9542] }, + { .compatible = "nxp,pca9543", .data = &chips[pca_9543] }, + { .compatible = "nxp,pca9544", .data = &chips[pca_9544] }, + { .compatible = "nxp,pca9545", .data = &chips[pca_9545] }, + { .compatible = "nxp,pca9546", .data = &chips[pca_9546] }, + { .compatible = "nxp,pca9547", .data = &chips[pca_9547] }, + { .compatible = "nxp,pca9548", .data = &chips[pca_9548] }, + { .compatible = "nxp,pca9846", .data = &chips[pca_9846] }, + { .compatible = "nxp,pca9847", .data = &chips[pca_9847] }, + { .compatible = "nxp,pca9848", .data = &chips[pca_9848] }, + { .compatible = "nxp,pca9849", .data = &chips[pca_9849] }, + {} +}; +MODULE_DEVICE_TABLE(of, pca954x_of_match); + +/* Write to mux register. Don't use i2c_transfer()/i2c_smbus_xfer() + for this as they will try to lock adapter a second time */ +static int pca954x_reg_write(struct i2c_adapter *adap, + struct i2c_client *client, u8 val) +{ + union i2c_smbus_data dummy; + + return __i2c_smbus_xfer(adap, client->addr, client->flags, + I2C_SMBUS_WRITE, val, + I2C_SMBUS_BYTE, &dummy); +} + +static u8 pca954x_regval(struct pca954x *data, u8 chan) +{ + /* We make switches look like muxes, not sure how to be smarter. */ + if (data->chip->muxtype == pca954x_ismux) + return chan | data->chip->enable; + else + return 1 << chan; +} + +static int pca954x_select_chan(struct i2c_mux_core *muxc, u32 chan) +{ + struct pca954x *data = i2c_mux_priv(muxc); + struct i2c_client *client = data->client; + u8 regval; + int ret = 0; + + regval = pca954x_regval(data, chan); + /* Only select the channel if its different from the last channel */ + if (data->last_chan != regval) { + ret = pca954x_reg_write(muxc->parent, client, regval); + data->last_chan = ret < 0 ? 0 : regval; + } + + return ret; +} + +static int pca954x_deselect_mux(struct i2c_mux_core *muxc, u32 chan) +{ + struct pca954x *data = i2c_mux_priv(muxc); + struct i2c_client *client = data->client; + s32 idle_state; + + idle_state = READ_ONCE(data->idle_state); + if (idle_state >= 0) + /* Set the mux back to a predetermined channel */ + return pca954x_select_chan(muxc, idle_state); + + if (idle_state == MUX_IDLE_DISCONNECT) { + /* Deselect active channel */ + data->last_chan = 0; + return pca954x_reg_write(muxc->parent, client, + data->last_chan); + } + + /* otherwise leave as-is */ + + return 0; +} + +static ssize_t idle_state_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + struct i2c_mux_core *muxc = i2c_get_clientdata(client); + struct pca954x *data = i2c_mux_priv(muxc); + + return sprintf(buf, "%d\n", READ_ONCE(data->idle_state)); +} + +static ssize_t idle_state_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + struct i2c_mux_core *muxc = i2c_get_clientdata(client); + struct pca954x *data = i2c_mux_priv(muxc); + int val; + int ret; + + ret = kstrtoint(buf, 0, &val); + if (ret < 0) + return ret; + + if (val != MUX_IDLE_AS_IS && val != MUX_IDLE_DISCONNECT && + (val < 0 || val >= data->chip->nchans)) + return -EINVAL; + + i2c_lock_bus(muxc->parent, I2C_LOCK_SEGMENT); + + WRITE_ONCE(data->idle_state, val); + /* + * Set the mux into a state consistent with the new + * idle_state. + */ + if (data->last_chan || val != MUX_IDLE_DISCONNECT) + ret = pca954x_deselect_mux(muxc, 0); + + i2c_unlock_bus(muxc->parent, I2C_LOCK_SEGMENT); + + return ret < 0 ? ret : count; +} + +static DEVICE_ATTR_RW(idle_state); + +static irqreturn_t pca954x_irq_handler(int irq, void *dev_id) +{ + struct pca954x *data = dev_id; + unsigned long pending; + int ret, i; + + ret = i2c_smbus_read_byte(data->client); + if (ret < 0) + return IRQ_NONE; + + pending = (ret >> PCA954X_IRQ_OFFSET) & (BIT(data->chip->nchans) - 1); + for_each_set_bit(i, &pending, data->chip->nchans) + handle_nested_irq(irq_linear_revmap(data->irq, i)); + + return IRQ_RETVAL(pending); +} + +static int pca954x_irq_set_type(struct irq_data *idata, unsigned int type) +{ + if ((type & IRQ_TYPE_SENSE_MASK) != IRQ_TYPE_LEVEL_LOW) + return -EINVAL; + return 0; +} + +static struct irq_chip pca954x_irq_chip = { + .name = "i2c-mux-pca954x", + .irq_set_type = pca954x_irq_set_type, +}; + +static int pca954x_irq_setup(struct i2c_mux_core *muxc) +{ + struct pca954x *data = i2c_mux_priv(muxc); + struct i2c_client *client = data->client; + int c, irq; + + if (!data->chip->has_irq || client->irq <= 0) + return 0; + + raw_spin_lock_init(&data->lock); + + data->irq = irq_domain_add_linear(client->dev.of_node, + data->chip->nchans, + &irq_domain_simple_ops, data); + if (!data->irq) + return -ENODEV; + + for (c = 0; c < data->chip->nchans; c++) { + irq = irq_create_mapping(data->irq, c); + if (!irq) { + dev_err(&client->dev, "failed irq create map\n"); + return -EINVAL; + } + irq_set_chip_data(irq, data); + irq_set_chip_and_handler(irq, &pca954x_irq_chip, + handle_simple_irq); + } + + return 0; +} + +static void pca954x_cleanup(struct i2c_mux_core *muxc) +{ + struct pca954x *data = i2c_mux_priv(muxc); + int c, irq; + + regulator_disable(data->supply); + + if (data->irq) { + for (c = 0; c < data->chip->nchans; c++) { + irq = irq_find_mapping(data->irq, c); + irq_dispose_mapping(irq); + } + irq_domain_remove(data->irq); + } + i2c_mux_del_adapters(muxc); +} + +static int pca954x_init(struct i2c_client *client, struct pca954x *data) +{ + int ret; + + if (data->idle_state >= 0) + data->last_chan = pca954x_regval(data, data->idle_state); + else + data->last_chan = 0; /* Disconnect multiplexer */ + + ret = i2c_smbus_write_byte(client, data->last_chan); + if (ret < 0) + data->last_chan = 0; + + return ret; +} + +/* + * I2C init/probing/exit functions + */ +static int pca954x_probe(struct i2c_client *client) +{ + const struct i2c_device_id *id = i2c_client_get_device_id(client); + struct i2c_adapter *adap = client->adapter; + struct device *dev = &client->dev; + struct gpio_desc *gpio; + struct i2c_mux_core *muxc; + struct pca954x *data; + int num; + int ret; + + if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE)) + return -ENODEV; + + muxc = i2c_mux_alloc(adap, dev, PCA954X_MAX_NCHANS, sizeof(*data), 0, + pca954x_select_chan, pca954x_deselect_mux); + if (!muxc) + return -ENOMEM; + data = i2c_mux_priv(muxc); + + i2c_set_clientdata(client, muxc); + data->client = client; + + data->supply = devm_regulator_get(dev, "vdd"); + if (IS_ERR(data->supply)) + return dev_err_probe(dev, PTR_ERR(data->supply), + "Failed to request regulator\n"); + + ret = regulator_enable(data->supply); + if (ret) + return dev_err_probe(dev, ret, + "Failed to enable vdd supply\n"); + + /* Reset the mux if a reset GPIO is specified. */ + gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(gpio)) { + ret = PTR_ERR(gpio); + goto fail_cleanup; + } + if (gpio) { + udelay(1); + gpiod_set_value_cansleep(gpio, 0); + /* Give the chip some time to recover. */ + udelay(1); + } + + data->chip = device_get_match_data(dev); + if (!data->chip) + data->chip = &chips[id->driver_data]; + + if (data->chip->id.manufacturer_id != I2C_DEVICE_ID_NONE) { + struct i2c_device_identity id; + + ret = i2c_get_device_id(client, &id); + if (ret && ret != -EOPNOTSUPP) + goto fail_cleanup; + + if (!ret && + (id.manufacturer_id != data->chip->id.manufacturer_id || + id.part_id != data->chip->id.part_id)) { + dev_warn(dev, "unexpected device id %03x-%03x-%x\n", + id.manufacturer_id, id.part_id, + id.die_revision); + ret = -ENODEV; + goto fail_cleanup; + } + } + + data->idle_state = MUX_IDLE_AS_IS; + if (device_property_read_u32(dev, "idle-state", &data->idle_state)) { + if (device_property_read_bool(dev, "i2c-mux-idle-disconnect")) + data->idle_state = MUX_IDLE_DISCONNECT; + } + + /* + * Write the mux register at addr to verify + * that the mux is in fact present. This also + * initializes the mux to a channel + * or disconnected state. + */ + ret = pca954x_init(client, data); + if (ret < 0) { + dev_warn(dev, "probe failed\n"); + ret = -ENODEV; + goto fail_cleanup; + } + + ret = pca954x_irq_setup(muxc); + if (ret) + goto fail_cleanup; + + /* Now create an adapter for each channel */ + for (num = 0; num < data->chip->nchans; num++) { + ret = i2c_mux_add_adapter(muxc, 0, num, 0); + if (ret) + goto fail_cleanup; + } + + if (data->irq) { + ret = devm_request_threaded_irq(dev, data->client->irq, + NULL, pca954x_irq_handler, + IRQF_ONESHOT | IRQF_SHARED, + "pca954x", data); + if (ret) + goto fail_cleanup; + } + + /* + * The attr probably isn't going to be needed in most cases, + * so don't fail completely on error. + */ + device_create_file(dev, &dev_attr_idle_state); + + dev_info(dev, "registered %d multiplexed busses for I2C %s %s\n", + num, data->chip->muxtype == pca954x_ismux + ? "mux" : "switch", client->name); + + return 0; + +fail_cleanup: + pca954x_cleanup(muxc); + return ret; +} + +static void pca954x_remove(struct i2c_client *client) +{ + struct i2c_mux_core *muxc = i2c_get_clientdata(client); + + device_remove_file(&client->dev, &dev_attr_idle_state); + + pca954x_cleanup(muxc); +} + +static int pca954x_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct i2c_mux_core *muxc = i2c_get_clientdata(client); + struct pca954x *data = i2c_mux_priv(muxc); + int ret; + + ret = pca954x_init(client, data); + if (ret < 0) + dev_err(&client->dev, "failed to verify mux presence\n"); + + return ret; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(pca954x_pm, NULL, pca954x_resume); + +static struct i2c_driver pca954x_driver = { + .driver = { + .name = "pca954x", + .pm = pm_sleep_ptr(&pca954x_pm), + .of_match_table = pca954x_of_match, + }, + .probe = pca954x_probe, + .remove = pca954x_remove, + .id_table = pca954x_id, +}; + +module_i2c_driver(pca954x_driver); + +MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>"); +MODULE_DESCRIPTION("PCA954x I2C mux/switch driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/muxes/i2c-mux-pinctrl.c b/drivers/i2c/muxes/i2c-mux-pinctrl.c new file mode 100644 index 000000000..6ebca7bfd --- /dev/null +++ b/drivers/i2c/muxes/i2c-mux-pinctrl.c @@ -0,0 +1,196 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * I2C multiplexer using pinctrl API + * + * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. + */ + +#include <linux/i2c.h> +#include <linux/i2c-mux.h> +#include <linux/module.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/of.h> +#include "../../pinctrl/core.h" + +struct i2c_mux_pinctrl { + struct pinctrl *pinctrl; + struct pinctrl_state *states[]; +}; + +static int i2c_mux_pinctrl_select(struct i2c_mux_core *muxc, u32 chan) +{ + struct i2c_mux_pinctrl *mux = i2c_mux_priv(muxc); + + return pinctrl_select_state(mux->pinctrl, mux->states[chan]); +} + +static int i2c_mux_pinctrl_deselect(struct i2c_mux_core *muxc, u32 chan) +{ + return i2c_mux_pinctrl_select(muxc, muxc->num_adapters); +} + +static struct i2c_adapter *i2c_mux_pinctrl_root_adapter( + struct pinctrl_state *state) +{ + struct i2c_adapter *root = NULL; + struct pinctrl_setting *setting; + struct i2c_adapter *pin_root; + + list_for_each_entry(setting, &state->settings, node) { + pin_root = i2c_root_adapter(setting->pctldev->dev); + if (!pin_root) + return NULL; + if (!root) + root = pin_root; + else if (root != pin_root) + return NULL; + } + + return root; +} + +static struct i2c_adapter *i2c_mux_pinctrl_parent_adapter(struct device *dev) +{ + struct device_node *np = dev->of_node; + struct device_node *parent_np; + struct i2c_adapter *parent; + + parent_np = of_parse_phandle(np, "i2c-parent", 0); + if (!parent_np) { + dev_err(dev, "Cannot parse i2c-parent\n"); + return ERR_PTR(-ENODEV); + } + parent = of_get_i2c_adapter_by_node(parent_np); + of_node_put(parent_np); + if (!parent) + return ERR_PTR(-EPROBE_DEFER); + + return parent; +} + +static int i2c_mux_pinctrl_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct i2c_mux_core *muxc; + struct i2c_mux_pinctrl *mux; + struct i2c_adapter *parent; + struct i2c_adapter *root; + int num_names, i, ret; + const char *name; + + num_names = of_property_count_strings(np, "pinctrl-names"); + if (num_names < 0) { + dev_err(dev, "Cannot parse pinctrl-names: %d\n", + num_names); + return num_names; + } + + parent = i2c_mux_pinctrl_parent_adapter(dev); + if (IS_ERR(parent)) + return PTR_ERR(parent); + + muxc = i2c_mux_alloc(parent, dev, num_names, + struct_size(mux, states, num_names), + 0, i2c_mux_pinctrl_select, NULL); + if (!muxc) { + ret = -ENOMEM; + goto err_put_parent; + } + mux = i2c_mux_priv(muxc); + + platform_set_drvdata(pdev, muxc); + + mux->pinctrl = devm_pinctrl_get(dev); + if (IS_ERR(mux->pinctrl)) { + ret = PTR_ERR(mux->pinctrl); + dev_err(dev, "Cannot get pinctrl: %d\n", ret); + goto err_put_parent; + } + + for (i = 0; i < num_names; i++) { + ret = of_property_read_string_index(np, "pinctrl-names", i, + &name); + if (ret < 0) { + dev_err(dev, "Cannot parse pinctrl-names: %d\n", ret); + goto err_put_parent; + } + + mux->states[i] = pinctrl_lookup_state(mux->pinctrl, name); + if (IS_ERR(mux->states[i])) { + ret = PTR_ERR(mux->states[i]); + dev_err(dev, "Cannot look up pinctrl state %s: %d\n", + name, ret); + goto err_put_parent; + } + + if (strcmp(name, "idle")) + continue; + + if (i != num_names - 1) { + dev_err(dev, "idle state must be last\n"); + ret = -EINVAL; + goto err_put_parent; + } + muxc->deselect = i2c_mux_pinctrl_deselect; + } + + root = i2c_root_adapter(&muxc->parent->dev); + + muxc->mux_locked = true; + for (i = 0; i < num_names; i++) { + if (root != i2c_mux_pinctrl_root_adapter(mux->states[i])) { + muxc->mux_locked = false; + break; + } + } + if (muxc->mux_locked) + dev_info(dev, "mux-locked i2c mux\n"); + + /* Do not add any adapter for the idle state (if it's there at all). */ + for (i = 0; i < num_names - !!muxc->deselect; i++) { + ret = i2c_mux_add_adapter(muxc, 0, i, 0); + if (ret) + goto err_del_adapter; + } + + return 0; + +err_del_adapter: + i2c_mux_del_adapters(muxc); +err_put_parent: + i2c_put_adapter(parent); + + return ret; +} + +static void i2c_mux_pinctrl_remove(struct platform_device *pdev) +{ + struct i2c_mux_core *muxc = platform_get_drvdata(pdev); + + i2c_mux_del_adapters(muxc); + i2c_put_adapter(muxc->parent); +} + +static const struct of_device_id i2c_mux_pinctrl_of_match[] = { + { .compatible = "i2c-mux-pinctrl", }, + {}, +}; +MODULE_DEVICE_TABLE(of, i2c_mux_pinctrl_of_match); + +static struct platform_driver i2c_mux_pinctrl_driver = { + .driver = { + .name = "i2c-mux-pinctrl", + .of_match_table = i2c_mux_pinctrl_of_match, + }, + .probe = i2c_mux_pinctrl_probe, + .remove_new = i2c_mux_pinctrl_remove, +}; +module_platform_driver(i2c_mux_pinctrl_driver); + +MODULE_DESCRIPTION("pinctrl-based I2C multiplexer driver"); +MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:i2c-mux-pinctrl"); diff --git a/drivers/i2c/muxes/i2c-mux-reg.c b/drivers/i2c/muxes/i2c-mux-reg.c new file mode 100644 index 000000000..9efc1ed01 --- /dev/null +++ b/drivers/i2c/muxes/i2c-mux-reg.c @@ -0,0 +1,264 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * I2C multiplexer using a single register + * + * Copyright 2015 Freescale Semiconductor + * York Sun <yorksun@freescale.com> + */ + +#include <linux/i2c.h> +#include <linux/i2c-mux.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/platform_data/i2c-mux-reg.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +struct regmux { + struct i2c_mux_reg_platform_data data; +}; + +static int i2c_mux_reg_set(const struct regmux *mux, unsigned int chan_id) +{ + if (!mux->data.reg) + return -EINVAL; + + /* + * Write to the register, followed by a read to ensure the write is + * completed on a "posted" bus, for example PCI or write buffers. + * The endianness of reading doesn't matter and the return data + * is not used. + */ + switch (mux->data.reg_size) { + case 4: + if (mux->data.little_endian) + iowrite32(chan_id, mux->data.reg); + else + iowrite32be(chan_id, mux->data.reg); + if (!mux->data.write_only) + ioread32(mux->data.reg); + break; + case 2: + if (mux->data.little_endian) + iowrite16(chan_id, mux->data.reg); + else + iowrite16be(chan_id, mux->data.reg); + if (!mux->data.write_only) + ioread16(mux->data.reg); + break; + case 1: + iowrite8(chan_id, mux->data.reg); + if (!mux->data.write_only) + ioread8(mux->data.reg); + break; + } + + return 0; +} + +static int i2c_mux_reg_select(struct i2c_mux_core *muxc, u32 chan) +{ + struct regmux *mux = i2c_mux_priv(muxc); + + return i2c_mux_reg_set(mux, chan); +} + +static int i2c_mux_reg_deselect(struct i2c_mux_core *muxc, u32 chan) +{ + struct regmux *mux = i2c_mux_priv(muxc); + + if (mux->data.idle_in_use) + return i2c_mux_reg_set(mux, mux->data.idle); + + return 0; +} + +#ifdef CONFIG_OF +static int i2c_mux_reg_probe_dt(struct regmux *mux, + struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct device_node *adapter_np, *child; + struct i2c_adapter *adapter; + struct resource res; + unsigned *values; + int i = 0; + + if (!np) + return -ENODEV; + + adapter_np = of_parse_phandle(np, "i2c-parent", 0); + if (!adapter_np) { + dev_err(&pdev->dev, "Cannot parse i2c-parent\n"); + return -ENODEV; + } + adapter = of_find_i2c_adapter_by_node(adapter_np); + of_node_put(adapter_np); + if (!adapter) + return -EPROBE_DEFER; + + mux->data.parent = i2c_adapter_id(adapter); + put_device(&adapter->dev); + + mux->data.n_values = of_get_child_count(np); + if (of_property_read_bool(np, "little-endian")) { + mux->data.little_endian = true; + } else if (of_property_read_bool(np, "big-endian")) { + mux->data.little_endian = false; + } else { +#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : \ + defined(__LITTLE_ENDIAN) + mux->data.little_endian = true; +#elif defined(__BYTE_ORDER) ? __BYTE_ORDER == __BIG_ENDIAN : \ + defined(__BIG_ENDIAN) + mux->data.little_endian = false; +#else +#error Endianness not defined? +#endif + } + mux->data.write_only = of_property_read_bool(np, "write-only"); + + values = devm_kcalloc(&pdev->dev, + mux->data.n_values, sizeof(*mux->data.values), + GFP_KERNEL); + if (!values) + return -ENOMEM; + + for_each_child_of_node(np, child) { + of_property_read_u32(child, "reg", values + i); + i++; + } + mux->data.values = values; + + if (!of_property_read_u32(np, "idle-state", &mux->data.idle)) + mux->data.idle_in_use = true; + + /* map address from "reg" if exists */ + if (of_address_to_resource(np, 0, &res) == 0) { + mux->data.reg_size = resource_size(&res); + mux->data.reg = devm_ioremap_resource(&pdev->dev, &res); + if (IS_ERR(mux->data.reg)) + return PTR_ERR(mux->data.reg); + } + + return 0; +} +#else +static int i2c_mux_reg_probe_dt(struct regmux *mux, + struct platform_device *pdev) +{ + return 0; +} +#endif + +static int i2c_mux_reg_probe(struct platform_device *pdev) +{ + struct i2c_mux_core *muxc; + struct regmux *mux; + struct i2c_adapter *parent; + struct resource *res; + unsigned int class; + int i, ret, nr; + + mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL); + if (!mux) + return -ENOMEM; + + if (dev_get_platdata(&pdev->dev)) { + memcpy(&mux->data, dev_get_platdata(&pdev->dev), + sizeof(mux->data)); + } else { + ret = i2c_mux_reg_probe_dt(mux, pdev); + if (ret < 0) + return dev_err_probe(&pdev->dev, ret, + "Error parsing device tree"); + } + + parent = i2c_get_adapter(mux->data.parent); + if (!parent) + return -EPROBE_DEFER; + + if (!mux->data.reg) { + dev_info(&pdev->dev, + "Register not set, using platform resource\n"); + mux->data.reg = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(mux->data.reg)) { + ret = PTR_ERR(mux->data.reg); + goto err_put_parent; + } + mux->data.reg_size = resource_size(res); + } + + if (mux->data.reg_size != 4 && mux->data.reg_size != 2 && + mux->data.reg_size != 1) { + dev_err(&pdev->dev, "Invalid register size\n"); + ret = -EINVAL; + goto err_put_parent; + } + + muxc = i2c_mux_alloc(parent, &pdev->dev, mux->data.n_values, 0, 0, + i2c_mux_reg_select, NULL); + if (!muxc) { + ret = -ENOMEM; + goto err_put_parent; + } + muxc->priv = mux; + + platform_set_drvdata(pdev, muxc); + + if (mux->data.idle_in_use) + muxc->deselect = i2c_mux_reg_deselect; + + for (i = 0; i < mux->data.n_values; i++) { + nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0; + class = mux->data.classes ? mux->data.classes[i] : 0; + + ret = i2c_mux_add_adapter(muxc, nr, mux->data.values[i], class); + if (ret) + goto err_del_mux_adapters; + } + + dev_dbg(&pdev->dev, "%d port mux on %s adapter\n", + mux->data.n_values, muxc->parent->name); + + return 0; + +err_del_mux_adapters: + i2c_mux_del_adapters(muxc); +err_put_parent: + i2c_put_adapter(parent); + + return ret; +} + +static void i2c_mux_reg_remove(struct platform_device *pdev) +{ + struct i2c_mux_core *muxc = platform_get_drvdata(pdev); + + i2c_mux_del_adapters(muxc); + i2c_put_adapter(muxc->parent); +} + +static const struct of_device_id i2c_mux_reg_of_match[] = { + { .compatible = "i2c-mux-reg", }, + {}, +}; +MODULE_DEVICE_TABLE(of, i2c_mux_reg_of_match); + +static struct platform_driver i2c_mux_reg_driver = { + .probe = i2c_mux_reg_probe, + .remove_new = i2c_mux_reg_remove, + .driver = { + .name = "i2c-mux-reg", + .of_match_table = of_match_ptr(i2c_mux_reg_of_match), + }, +}; + +module_platform_driver(i2c_mux_reg_driver); + +MODULE_DESCRIPTION("Register-based I2C multiplexer driver"); +MODULE_AUTHOR("York Sun <yorksun@freescale.com>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:i2c-mux-reg"); |