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-rw-r--r--drivers/i2c/busses/i2c-ali1535.c532
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diff --git a/drivers/i2c/busses/i2c-ali1535.c b/drivers/i2c/busses/i2c-ali1535.c
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+++ 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");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 12:05:48 +0000