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path: root/drivers/i2c/busses/i2c-sis630.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-sis630.c')
-rw-r--r--drivers/i2c/busses/i2c-sis630.c557
1 files changed, 557 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..1e6805b5c
--- /dev/null
+++ b/drivers/i2c/busses/i2c-sis630.c
@@ -0,0 +1,557 @@
+/*
+ Copyright (c) 2002,2003 Alexander Malysh <amalysh@web.de>
+
+ 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.
+
+ 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.
+*/
+
+/*
+ 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%04hx-0x%04hx 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 %04hx", 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");