diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/i2c/busses/i2c-sis630.c | 549 |
1 files changed, 549 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-sis630.c b/drivers/i2c/busses/i2c-sis630.c new file mode 100644 index 000000000..cfb8e04a2 --- /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 adress */ +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"); |