File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/i2c/busses/i2c-sis5595.c b/drivers/i2c/busses/i2c-sis5595.c
new file mode 100644
index 0000000..7d58a40
--- /dev/null
+++ b/drivers/i2c/busses/i2c-sis5595.c
@@ -0,0 +1,430 @@
+/*
+    Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl> and
+    Philip Edelbrock <phil@netroedge.com>
+
+    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.
+*/
+
+/* 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(force_addr, ushort, 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);
+		if (pci_write_config_word(SIS5595_dev, ACPI_BASE, sis5595_base)
+		    != PCIBIOS_SUCCESSFUL)
+			goto error;
+		if (pci_read_config_word(SIS5595_dev, ACPI_BASE, &a)
+		    != 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;
+		}
+	}
+
+	if (pci_read_config_byte(SIS5595_dev, SIS5595_ENABLE_REG, &val)
+	    != PCIBIOS_SUCCESSFUL)
+		goto error;
+	if ((val & 0x80) == 0) {
+		dev_info(&SIS5595_dev->dev, "enabling ACPI\n");
+		if (pci_write_config_byte(SIS5595_dev, SIS5595_ENABLE_REG, val | 0x80)
+		    != PCIBIOS_SUCCESSFUL)
+			goto error;
+		if (pci_read_config_byte(SIS5595_dev, SIS5595_ENABLE_REG, &val)
+		    != 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);