[PATCH] I2C: add the i2c-sis630 i2c bus driver

This is based on the lmsensor cvs version of the driver, but is cleaned
it up and ported it to 2.6.

drivers/i2c/busses/Kconfig

@@ -166,6 +166,22 @@ config I2C_SIS5595
 	  in the lm_sensors package, which you can download at 
 	  http://www.lm-sensors.nu
 
+config I2C_SIS630
+	tristate "  Sis630"
+	depends on I2C && PCI && EXPERIMENTAL
+	help
+	  If you say yes to this option, support will be included for the 
+	  SiS630 SMBus (a subset of I2C) interface.
+
+	  This can also be built as a module which can be inserted and removed 
+	  while the kernel is running.  If you want to compile it as a module,
+	  say M here and read <file:Documentation/modules.txt>.
+
+	  The module will be called i2c-sis630.
+
+	  You will also need the latest user-space utilties: you can find them
+	  in the lm_sensors package, which you can download at 
+	  http://www.lm-sensors.nu
 
 config I2C_SIS96X
 	tristate "  SiS 96x"

drivers/i2c/busses/Makefile

@@ -11,5 +11,6 @@ obj-$(CONFIG_I2C_ISA)		+= i2c-isa.o
 obj-$(CONFIG_I2C_NFORCE2)	+= i2c-nforce2.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_VIAPRO)	+= i2c-viapro.o

drivers/i2c/busses/i2c-sis630.c

+/*
+    i2c-sis630.c - Part of lm_sensors, Linux kernel modules for hardware
+              monitoring
+
+    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.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+/*
+   Changes:
+   24.08.2002
+   	Fixed the typo in sis630_access (Thanks to Mark M. Hoffman)
+	Changed sis630_transaction.(Thanks to Mark M. Hoffman)
+   18.09.2002
+	Added SIS730 as supported
+   21.09.2002
+	Added high_clock module option.If this option is set
+	used Host Master Clock 56KHz (default 14KHz).For now we are save old Host
+	Master Clock and after transaction completed restore (otherwise
+	it's confuse BIOS and hung Machine).
+   24.09.2002
+	Fixed typo in sis630_access
+	Fixed logical error by restoring of Host Master Clock
+   31.07.2003
+   	Added block data read/write support.
+*/
+
+/*
+   Status: beta
+
+   Supports:
+	SIS 630
+	SIS 730
+
+   Note: we assume there can only be one device, with one SMBus interface.
+*/
+
+#define DEBUG
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+
+
+/* SIS630 SMBus registers */
+#define SMB_STS			0x80	/* status */
+#define SMB_EN			0x81	/* status enable */
+#define SMB_CNT			0x82
+#define SMBHOST_CNT		0x83
+#define SMB_ADDR		0x84
+#define SMB_CMD			0x85
+#define SMB_PCOUNT		0x86	/* processed count */
+#define SMB_COUNT		0x87
+#define SMB_BYTE		0x88	/* ~0x8F data byte field */
+#define SMBDEV_ADDR		0x90
+#define SMB_DB0			0x91
+#define SMB_DB1			0x92
+#define SMB_SAA			0x93
+
+/* register count for request_region */
+#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
+
+/* insmod parameters */
+static int high_clock = 0;
+MODULE_PARM(high_clock, "i");
+MODULE_PARM_DESC(high_clock, "Set Host Master Clock to 56KHz (default 14KHz).");
+
+
+static unsigned short acpi_base = 0;
+
+static inline u8 sis630_read(u8 reg)
+{
+	return inb(acpi_base + reg);
+}
+
+static inline void sis630_write(u8 reg, u8 data)
+{
+	outb(data, acpi_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. */
+	if ((temp = sis630_read(SMB_CNT) & 0x03) != 0x00) {
+		dev_dbg(&adap->dev, "SMBus busy (%02x).Resetting...\n",temp);
+		/* kill smbus transaction */
+		sis630_write(SMBHOST_CNT, 0x20);
+
+		if ((temp = sis630_read(SMB_CNT) & 0x03) != 0x00) {
+			dev_dbg(&adap->dev, "Failed! (%02x)\n", temp);
+			return -1;
+                } else {
+			dev_dbg(&adap->dev, "Successfull!\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 > 0)
+		sis630_write(SMB_CNT, 0x20);
+	else
+		sis630_write(SMB_CNT, (*oldclock & ~0x40));
+
+	/* 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,0x10 | (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 {
+		i2c_delay(1);
+		temp = sis630_read(SMB_STS);
+		/* check if block transmitted */
+		if (size == SIS630_BLOCK_DATA && (temp & 0x10))
+			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 = -1;
+	}
+
+	if (temp & 0x02) {
+		dev_dbg(&adap->dev, "Error: Failed bus transaction\n");
+		result = -1;
+	}
+
+	if (temp & 0x04) {
+		dev_err(&adap->dev, "Bus collision!\n");
+		result = -1;
+		/*
+		  TBD: Datasheet say:
+		  the software should clear this bit and restart SMBUS operation.
+		  Should we do it or user start request again?
+		*/
+	}
+
+	return result;
+}
+
+static void sis630_transaction_end(struct i2c_adapter *adap, u8 oldclock)
+{
+	int temp = 0;
+
+	/* clear all status "sticky" bits */
+	sis630_write(SMB_STS, temp);
+
+	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 > 0 && !(oldclock & 0x20))
+		sis630_write(SMB_CNT,(sis630_read(SMB_CNT) & ~0x20));
+
+	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 */
+				if (sis630_transaction_start(adap, SIS630_BLOCK_DATA, &oldclock))
+					return -1;
+			}
+			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,0x10);
+				}
+				if (sis630_transaction_wait(adap, SIS630_BLOCK_DATA)) {
+					dev_dbg(&adap->dev, "trans_wait failed\n");
+					rc = -1;
+					break;
+				}
+			}
+		}
+	}
+	else {
+		/* read request */
+		data->block[0] = len = 0;
+		if (sis630_transaction_start(adap, SIS630_BLOCK_DATA, &oldclock)) {
+			return -1;
+		}
+		do {
+			if (sis630_transaction_wait(adap, SIS630_BLOCK_DATA)) {
+				dev_dbg(&adap->dev, "trans_wait failed\n");
+				rc = -1;
+				break;
+			}
+			/* if this first transaction then read byte count */
+			if (len == 0)
+				data->block[0] = sis630_read(SMB_COUNT);
+
+			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,0x10);
+		} while(len < data->block[0]);
+	}
+
+	sis630_transaction_end(adap, oldclock);
+
+	return rc;
+}
+
+/* Return -1 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)
+{
+	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:
+			printk("Unsupported I2C size\n");
+			return -1;
+			break;
+	}
+
+	if (sis630_transaction(adap, size))
+		return -1;
+
+	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;
+		default:
+			return -1;
+			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 *dummy)
+{
+	unsigned char b;
+	struct pci_dev *sis630_dev = NULL;
+	int retval = -ENODEV;
+
+	/* We need ISA bridge and not pci device passed in.  */
+	sis630_dev = pci_get_device(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_503, sis630_dev);
+	if (!sis630_dev) {
+		dev_err(&dummy->dev, "Error: Can't detect 85C503/5513 ISA bridge!\n");
+		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");
+		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");
+		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");
+		goto exit;
+	}
+
+	dev_dbg(&sis630_dev->dev, "ACPI base at 0x%04x\n", acpi_base);
+
+	/* Everything is happy, let's grab the memory and set things up. */
+	if (!request_region(acpi_base + SMB_STS, SIS630_SMB_IOREGION, "sis630-smbus")) {
+		dev_err(&sis630_dev->dev, "SMBus registers 0x%04x-0x%04x already "
+			"in use!\n", acpi_base + SMB_STS, acpi_base + SMB_SAA);
+		goto exit;
+	}
+
+	retval = 0;
+
+exit:
+	pci_dev_put(sis630_dev);
+	return retval;
+}
+
+
+static struct i2c_algorithm smbus_algorithm = {
+	.name		= "Non-I2C SMBus adapter",
+	.id		= I2C_ALGO_SMBUS,
+	.smbus_xfer	= sis630_access,
+	.functionality	= sis630_func,
+};
+
+static struct i2c_adapter sis630_adapter = {
+	.owner		= THIS_MODULE,
+	.name		= "unset",
+	.algo		= &smbus_algorithm,
+};
+
+static struct pci_device_id sis630_ids[] __devinitdata = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_630) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_730) },
+	{ 0, }
+};
+
+static int __devinit sis630_probe(struct pci_dev *dev, const struct pci_device_id *id)
+{
+
+	if (sis630_setup(dev)) {
+		dev_err(&dev->dev, "SIS630 comp. bus not detected, module not inserted.\n");
+		return -ENODEV;
+	}
+
+	/* set up the driverfs linkage to our parent device */
+	sis630_adapter.dev.parent = &dev->dev;
+
+	sprintf(sis630_adapter.name, "SMBus SIS630 adapter at %04x",
+		acpi_base + SMB_STS);
+
+	return i2c_add_adapter(&sis630_adapter);
+}
+
+static void __devexit sis630_remove(struct pci_dev *dev)
+{
+	i2c_del_adapter(&sis630_adapter);
+}
+
+
+static struct pci_driver sis630_driver = {
+	.name		= "sis630 smbus",
+	.id_table	= sis630_ids,
+	.probe		= sis630_probe,
+	.remove		= __devexit_p(sis630_remove),
+};
+
+static int __init i2c_sis630_init(void)
+{
+	printk("i2c-sis630.o version %s (%s)\n", I2C_VERSION, I2C_DATE);
+	return pci_module_init(&sis630_driver);
+}
+
+
+static void __exit i2c_sis630_exit(void)
+{
+	pci_unregister_driver(&sis630_driver);
+	release_region(acpi_base + SMB_STS, SIS630_SMB_IOREGION);
+}
+
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Alexander Malysh <amalysh@web.de>");
+MODULE_DESCRIPTION("SIS630 SMBus driver");
+
+module_init(i2c_sis630_init);
+module_exit(i2c_sis630_exit);