1 files changed, 136 insertions, 148 deletions

diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index b0f771fe4326..dc7ea32b69a8 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -1,10 +1,8 @@
 /*
-    i2c-i801.c - Part of lm_sensors, Linux kernel modules for hardware
-              monitoring
     Copyright (c) 1998 - 2002  Frodo Looijaard <frodol@dds.nl>,
     Philip Edelbrock <phil@netroedge.com>, and Mark D. Studebaker
     <mdsxyz123@yahoo.com>
-    Copyright (C) 2007         Jean Delvare <khali@linux-fr.org>
+    Copyright (C) 2007, 2008   Jean Delvare <khali@linux-fr.org>
 
     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
@@ -64,6 +62,7 @@
 #include <linux/ioport.h>
 #include <linux/init.h>
 #include <linux/i2c.h>
+#include <linux/acpi.h>
 #include <asm/io.h>
 
 /* I801 SMBus address offsets */
@@ -121,6 +120,10 @@
 #define SMBHSTSTS_INTR		0x02
 #define SMBHSTSTS_HOST_BUSY	0x01
 
+#define STATUS_FLAGS		(SMBHSTSTS_BYTE_DONE | SMBHSTSTS_FAILED | \
+				 SMBHSTSTS_BUS_ERR | SMBHSTSTS_DEV_ERR | \
+				 SMBHSTSTS_INTR)
+
 static unsigned long i801_smba;
 static unsigned char i801_original_hstcfg;
 static struct pci_driver i801_driver;
@@ -132,105 +135,137 @@ static struct pci_dev *I801_dev;
 #define FEATURE_I2C_BLOCK_READ	(1 << 3)
 static unsigned int i801_features;
 
-static int i801_transaction(int xact)
+/* Make sure the SMBus host is ready to start transmitting.
+   Return 0 if it is, -EBUSY if it is not. */
+static int i801_check_pre(void)
 {
-	int temp;
-	int result = 0;
-	int timeout = 0;
+	int status;
 
-	dev_dbg(&I801_dev->dev, "Transaction (pre): CNT=%02x, CMD=%02x, "
-		"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
-		inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
-		inb_p(SMBHSTDAT1));
-
-	/* Make sure the SMBus host is ready to start transmitting */
-	/* 0x1f = Failed, Bus_Err, Dev_Err, Intr, Host_Busy */
-	if ((temp = (0x1f & inb_p(SMBHSTSTS))) != 0x00) {
-		dev_dbg(&I801_dev->dev, "SMBus busy (%02x). Resetting...\n",
-			temp);
-		outb_p(temp, SMBHSTSTS);
-		if ((temp = (0x1f & inb_p(SMBHSTSTS))) != 0x00) {
-			dev_dbg(&I801_dev->dev, "Failed! (%02x)\n", temp);
-			return -1;
-		} else {
-			dev_dbg(&I801_dev->dev, "Successful!\n");
+	status = inb_p(SMBHSTSTS);
+	if (status & SMBHSTSTS_HOST_BUSY) {
+		dev_err(&I801_dev->dev, "SMBus is busy, can't use it!\n");
+		return -EBUSY;
+	}
+
+	status &= STATUS_FLAGS;
+	if (status) {
+		dev_dbg(&I801_dev->dev, "Clearing status flags (%02x)\n",
+			status);
+		outb_p(status, SMBHSTSTS);
+		status = inb_p(SMBHSTSTS) & STATUS_FLAGS;
+		if (status) {
+			dev_err(&I801_dev->dev,
+				"Failed clearing status flags (%02x)\n",
+				status);
+			return -EBUSY;
 		}
 	}
 
-	/* the current contents of SMBHSTCNT can be overwritten, since PEC,
-	 * INTREN, SMBSCMD are passed in xact */
-	outb_p(xact | I801_START, SMBHSTCNT);
+	return 0;
+}
 
-	/* We will always wait for a fraction of a second! */
-	do {
-		msleep(1);
-		temp = inb_p(SMBHSTSTS);
-	} while ((temp & SMBHSTSTS_HOST_BUSY) && (timeout++ < MAX_TIMEOUT));
+/* Convert the status register to an error code, and clear it. */
+static int i801_check_post(int status, int timeout)
+{
+	int result = 0;
 
 	/* If the SMBus is still busy, we give up */
-	if (timeout >= MAX_TIMEOUT) {
-		dev_dbg(&I801_dev->dev, "SMBus Timeout!\n");
-		result = -1;
+	if (timeout) {
+		dev_err(&I801_dev->dev, "Transaction timeout\n");
 		/* try to stop the current command */
 		dev_dbg(&I801_dev->dev, "Terminating the current operation\n");
 		outb_p(inb_p(SMBHSTCNT) | SMBHSTCNT_KILL, SMBHSTCNT);
 		msleep(1);
 		outb_p(inb_p(SMBHSTCNT) & (~SMBHSTCNT_KILL), SMBHSTCNT);
-	}
 
-	if (temp & SMBHSTSTS_FAILED) {
-		result = -1;
-		dev_dbg(&I801_dev->dev, "Error: Failed bus transaction\n");
+		/* Check if it worked */
+		status = inb_p(SMBHSTSTS);
+		if ((status & SMBHSTSTS_HOST_BUSY) ||
+		    !(status & SMBHSTSTS_FAILED))
+			dev_err(&I801_dev->dev,
+				"Failed terminating the transaction\n");
+		outb_p(STATUS_FLAGS, SMBHSTSTS);
+		return -ETIMEDOUT;
 	}
 
-	if (temp & SMBHSTSTS_BUS_ERR) {
-		result = -1;
-		dev_err(&I801_dev->dev, "Bus collision! SMBus may be locked "
-			"until next hard reset. (sorry!)\n");
-		/* Clock stops and slave is stuck in mid-transmission */
+	if (status & SMBHSTSTS_FAILED) {
+		result = -EIO;
+		dev_err(&I801_dev->dev, "Transaction failed\n");
 	}
-
-	if (temp & SMBHSTSTS_DEV_ERR) {
-		result = -1;
-		dev_dbg(&I801_dev->dev, "Error: no response!\n");
+	if (status & SMBHSTSTS_DEV_ERR) {
+		result = -ENXIO;
+		dev_dbg(&I801_dev->dev, "No response\n");
+	}
+	if (status & SMBHSTSTS_BUS_ERR) {
+		result = -EAGAIN;
+		dev_dbg(&I801_dev->dev, "Lost arbitration\n");
 	}
 
-	if ((inb_p(SMBHSTSTS) & 0x1f) != 0x00)
-		outb_p(inb(SMBHSTSTS), SMBHSTSTS);
-
-	if ((temp = (0x1f & inb_p(SMBHSTSTS))) != 0x00) {
-		dev_dbg(&I801_dev->dev, "Failed reset at end of transaction "
-			"(%02x)\n", temp);
+	if (result) {
+		/* Clear error flags */
+		outb_p(status & STATUS_FLAGS, SMBHSTSTS);
+		status = inb_p(SMBHSTSTS) & STATUS_FLAGS;
+		if (status) {
+			dev_warn(&I801_dev->dev, "Failed clearing status "
+				 "flags at end of transaction (%02x)\n",
+				 status);
+		}
 	}
-	dev_dbg(&I801_dev->dev, "Transaction (post): CNT=%02x, CMD=%02x, "
-		"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
-		inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
-		inb_p(SMBHSTDAT1));
+
 	return result;
 }
 
+static int i801_transaction(int xact)
+{
+	int status;
+	int result;
+	int timeout = 0;
+
+	result = i801_check_pre();
+	if (result < 0)
+		return result;
+
+	/* the current contents of SMBHSTCNT can be overwritten, since PEC,
+	 * INTREN, SMBSCMD are passed in xact */
+	outb_p(xact | I801_START, SMBHSTCNT);
+
+	/* We will always wait for a fraction of a second! */
+	do {
+		msleep(1);
+		status = inb_p(SMBHSTSTS);
+	} while ((status & SMBHSTSTS_HOST_BUSY) && (timeout++ < MAX_TIMEOUT));
+
+	result = i801_check_post(status, timeout >= MAX_TIMEOUT);
+	if (result < 0)
+		return result;
+
+	outb_p(SMBHSTSTS_INTR, SMBHSTSTS);
+	return 0;
+}
+
 /* wait for INTR bit as advised by Intel */
 static void i801_wait_hwpec(void)
 {
 	int timeout = 0;
-	int temp;
+	int status;
 
 	do {
 		msleep(1);
-		temp = inb_p(SMBHSTSTS);
-	} while ((!(temp & SMBHSTSTS_INTR))
+		status = inb_p(SMBHSTSTS);
+	} while ((!(status & SMBHSTSTS_INTR))
 		 && (timeout++ < MAX_TIMEOUT));
 
 	if (timeout >= MAX_TIMEOUT) {
 		dev_dbg(&I801_dev->dev, "PEC Timeout!\n");
 	}
-	outb_p(temp, SMBHSTSTS);
+	outb_p(status, SMBHSTSTS);
 }
 
 static int i801_block_transaction_by_block(union i2c_smbus_data *data,
 					   char read_write, int hwpec)
 {
 	int i, len;
+	int status;
 
 	inb_p(SMBHSTCNT); /* reset the data buffer index */
 
@@ -242,14 +277,15 @@ static int i801_block_transaction_by_block(union i2c_smbus_data *data,
 			outb_p(data->block[i+1], SMBBLKDAT);
 	}
 
-	if (i801_transaction(I801_BLOCK_DATA | ENABLE_INT9 |
-			     I801_PEC_EN * hwpec))
-		return -1;
+	status = i801_transaction(I801_BLOCK_DATA | ENABLE_INT9 |
+				  I801_PEC_EN * hwpec);
+	if (status)
+		return status;
 
 	if (read_write == I2C_SMBUS_READ) {
 		len = inb_p(SMBHSTDAT0);
 		if (len < 1 || len > I2C_SMBUS_BLOCK_MAX)
-			return -1;
+			return -EPROTO;
 
 		data->block[0] = len;
 		for (i = 0; i < len; i++)
@@ -264,10 +300,13 @@ static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,
 {
 	int i, len;
 	int smbcmd;
-	int temp;
-	int result = 0;
+	int status;
+	int result;
 	int timeout;
-	unsigned char errmask;
+
+	result = i801_check_pre();
+	if (result < 0)
+		return result;
 
 	len = data->block[0];
 
@@ -291,36 +330,6 @@ static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,
 		}
 		outb_p(smbcmd | ENABLE_INT9, SMBHSTCNT);
 
-		dev_dbg(&I801_dev->dev, "Block (pre %d): CNT=%02x, CMD=%02x, "
-			"ADD=%02x, DAT0=%02x, DAT1=%02x, BLKDAT=%02x\n", i,
-			inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
-			inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1), inb_p(SMBBLKDAT));
-
-		/* Make sure the SMBus host is ready to start transmitting */
-		temp = inb_p(SMBHSTSTS);
-		if (i == 1) {
-			/* Erroneous conditions before transaction:
-			 * Byte_Done, Failed, Bus_Err, Dev_Err, Intr, Host_Busy */
-			errmask = 0x9f;
-		} else {
-			/* Erroneous conditions during transaction:
-			 * Failed, Bus_Err, Dev_Err, Intr */
-			errmask = 0x1e;
-		}
-		if (temp & errmask) {
-			dev_dbg(&I801_dev->dev, "SMBus busy (%02x). "
-				"Resetting...\n", temp);
-			outb_p(temp, SMBHSTSTS);
-			if (((temp = inb_p(SMBHSTSTS)) & errmask) != 0x00) {
-				dev_err(&I801_dev->dev,
-					"Reset failed! (%02x)\n", temp);
-				return -1;
-			}
-			if (i != 1)
-				/* if die in middle of block transaction, fail */
-				return -1;
-		}
-
 		if (i == 1)
 			outb_p(inb(SMBHSTCNT) | I801_START, SMBHSTCNT);
 
@@ -328,41 +337,28 @@ static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,
 		timeout = 0;
 		do {
 			msleep(1);
-			temp = inb_p(SMBHSTSTS);
+			status = inb_p(SMBHSTSTS);
 		}
-		while ((!(temp & SMBHSTSTS_BYTE_DONE))
+		while ((!(status & SMBHSTSTS_BYTE_DONE))
 		       && (timeout++ < MAX_TIMEOUT));
 
-		/* If the SMBus is still busy, we give up */
-		if (timeout >= MAX_TIMEOUT) {
-			/* try to stop the current command */
-			dev_dbg(&I801_dev->dev, "Terminating the current "
-						"operation\n");
-			outb_p(inb_p(SMBHSTCNT) | SMBHSTCNT_KILL, SMBHSTCNT);
-			msleep(1);
-			outb_p(inb_p(SMBHSTCNT) & (~SMBHSTCNT_KILL),
-				SMBHSTCNT);
-			result = -1;
-			dev_dbg(&I801_dev->dev, "SMBus Timeout!\n");
-		}
-
-		if (temp & SMBHSTSTS_FAILED) {
-			result = -1;
-			dev_dbg(&I801_dev->dev,
-				"Error: Failed bus transaction\n");
-		} else if (temp & SMBHSTSTS_BUS_ERR) {
-			result = -1;
-			dev_err(&I801_dev->dev, "Bus collision!\n");
-		} else if (temp & SMBHSTSTS_DEV_ERR) {
-			result = -1;
-			dev_dbg(&I801_dev->dev, "Error: no response!\n");
-		}
+		result = i801_check_post(status, timeout >= MAX_TIMEOUT);
+		if (result < 0)
+			return result;
 
 		if (i == 1 && read_write == I2C_SMBUS_READ
 		 && command != I2C_SMBUS_I2C_BLOCK_DATA) {
 			len = inb_p(SMBHSTDAT0);
-			if (len < 1 || len > I2C_SMBUS_BLOCK_MAX)
-				return -1;
+			if (len < 1 || len > I2C_SMBUS_BLOCK_MAX) {
+				dev_err(&I801_dev->dev,
+					"Illegal SMBus block read size %d\n",
+					len);
+				/* Recover */
+				while (inb_p(SMBHSTSTS) & SMBHSTSTS_HOST_BUSY)
+					outb_p(SMBHSTSTS_BYTE_DONE, SMBHSTSTS);
+				outb_p(SMBHSTSTS_INTR, SMBHSTSTS);
+				return -EPROTO;
+			}
 			data->block[0] = len;
 		}
 
@@ -371,30 +367,19 @@ static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,
 			data->block[i] = inb_p(SMBBLKDAT);
 		if (read_write == I2C_SMBUS_WRITE && i+1 <= len)
 			outb_p(data->block[i+1], SMBBLKDAT);
-		if ((temp & 0x9e) != 0x00)
-			outb_p(temp, SMBHSTSTS);  /* signals SMBBLKDAT ready */
-
-		if ((temp = (0x1e & inb_p(SMBHSTSTS))) != 0x00) {
-			dev_dbg(&I801_dev->dev,
-				"Bad status (%02x) at end of transaction\n",
-				temp);
-		}
-		dev_dbg(&I801_dev->dev, "Block (post %d): CNT=%02x, CMD=%02x, "
-			"ADD=%02x, DAT0=%02x, DAT1=%02x, BLKDAT=%02x\n", i,
-			inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
-			inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1), inb_p(SMBBLKDAT));
 
-		if (result < 0)
-			return result;
+		/* signals SMBBLKDAT ready */
+		outb_p(SMBHSTSTS_BYTE_DONE | SMBHSTSTS_INTR, SMBHSTSTS);
 	}
-	return result;
+
+	return 0;
 }
 
 static int i801_set_block_buffer_mode(void)
 {
 	outb_p(inb_p(SMBAUXCTL) | SMBAUXCTL_E32B, SMBAUXCTL);
 	if ((inb_p(SMBAUXCTL) & SMBAUXCTL_E32B) == 0)
-		return -1;
+		return -EIO;
 	return 0;
 }
 
@@ -414,7 +399,7 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
 		} else if (!(i801_features & FEATURE_I2C_BLOCK_READ)) {
 			dev_err(&I801_dev->dev,
 				"I2C block read is unsupported!\n");
-			return -1;
+			return -EOPNOTSUPP;
 		}
 	}
 
@@ -449,7 +434,7 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
 	return result;
 }
 
-/* Return -1 on error. */
+/* Return negative errno on error. */
 static s32 i801_access(struct i2c_adapter * adap, u16 addr,
 		       unsigned short flags, char read_write, u8 command,
 		       int size, union i2c_smbus_data * data)
@@ -511,10 +496,9 @@ static s32 i801_access(struct i2c_adapter * adap, u16 addr,
 			outb_p(command, SMBHSTCMD);
 		block = 1;
 		break;
-	case I2C_SMBUS_PROC_CALL:
 	default:
 		dev_err(&I801_dev->dev, "Unsupported transaction %d\n", size);
-		return -1;
+		return -EOPNOTSUPP;
 	}
 
 	if (hwpec)	/* enable/disable hardware PEC */
@@ -537,7 +521,7 @@ static s32 i801_access(struct i2c_adapter * adap, u16 addr,
 	if(block)
 		return ret;
 	if(ret)
-		return -1;
+		return ret;
 	if ((read_write == I2C_SMBUS_WRITE) || (xact == I801_QUICK))
 		return 0;
 
@@ -572,7 +556,7 @@ static const struct i2c_algorithm smbus_algorithm = {
 static struct i2c_adapter i801_adapter = {
 	.owner		= THIS_MODULE,
 	.id		= I2C_HW_SMBUS_I801,
-	.class		= I2C_CLASS_HWMON,
+	.class		= I2C_CLASS_HWMON | I2C_CLASS_SPD,
 	.algo		= &smbus_algorithm,
 };
 
@@ -639,6 +623,10 @@ static int __devinit i801_probe(struct pci_dev *dev, const struct pci_device_id
 		goto exit;
 	}
 
+	err = acpi_check_resource_conflict(&dev->resource[SMBBAR]);
+	if (err)
+		goto exit;
+
 	err = pci_request_region(dev, SMBBAR, i801_driver.name);
 	if (err) {
 		dev_err(&dev->dev, "Failed to request SMBus region "