[PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[David Woodhouse]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 25665 bytes --]


Signed-off-by: David Woodhouse <David.Woodhouse-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
  drivers/i2c/busses/i2c-i801.c |  329 ++++++++++++++++++++++-------------------
  1 files changed, 178 insertions(+), 151 deletions(-)

diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 59d6598..6e8c12c 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -1,8 +1,10 @@
  /*
-    Copyright (c) 1998 - 2002  Frodo Looijaard <frodol-B0qZmFHriGg@public.gmane.org>,
-    Philip Edelbrock <phil-KXOFo5pg7o1l57MIdRCFDg@public.gmane.org>, and Mark D. Studebaker
-    <mdsxyz123-/E1597aS9LQAvxtiuMwx3w@public.gmane.org>
-    Copyright (C) 2007, 2008   Jean Delvare <khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org>
+    Copyright © 1998 - 2002  Frodo Looijaard <frodol-B0qZmFHriGg@public.gmane.org>,
+			     Philip Edelbrock <phil-KXOFo5pg7o1l57MIdRCFDg@public.gmane.org> and
+			     Mark D. Studebaker <mdsxyz123-/E1597aS9LQAvxtiuMwx3w@public.gmane.org>
+    Copyright © 2007, 2008   Jean Delvare <khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org>
+    Copyright © 2010         Intel Corporation
+                             David Woodhouse <dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.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
@@ -54,8 +56,6 @@
    See the file Documentation/i2c/busses/i2c-i801 for details.
  */

-/* Note: we assume there can only be one I801, with one SMBus interface */
-
  #include <linux/module.h>
  #include <linux/pci.h>
  #include <linux/kernel.h>
@@ -69,16 +69,16 @@
  #include <linux/dmi.h>

  /* I801 SMBus address offsets */
-#define SMBHSTSTS	(0 + i801_smba)
-#define SMBHSTCNT	(2 + i801_smba)
-#define SMBHSTCMD	(3 + i801_smba)
-#define SMBHSTADD	(4 + i801_smba)
-#define SMBHSTDAT0	(5 + i801_smba)
-#define SMBHSTDAT1	(6 + i801_smba)
-#define SMBBLKDAT	(7 + i801_smba)
-#define SMBPEC		(8 + i801_smba)		/* ICH3 and later */
-#define SMBAUXSTS	(12 + i801_smba)	/* ICH4 and later */
-#define SMBAUXCTL	(13 + i801_smba)	/* ICH4 and later */
+#define SMBHSTSTS(p)	(0 + (p)->smba)
+#define SMBHSTCNT(p)	(2 + (p)->smba)
+#define SMBHSTCMD(p)	(3 + (p)->smba)
+#define SMBHSTADD(p)	(4 + (p)->smba)
+#define SMBHSTDAT0(p)	(5 + (p)->smba)
+#define SMBHSTDAT1(p)	(6 + (p)->smba)
+#define SMBBLKDAT(p)	(7 + (p)->smba)
+#define SMBPEC(p)	(8 + (p)->smba)		/* ICH3 and later */
+#define SMBAUXSTS(p)	(12 + (p)->smba)	/* ICH4 and later */
+#define SMBAUXCTL(p)	(13 + (p)->smba)	/* ICH4 and later */

  /* PCI Address Constants */
  #define SMBBAR		4
@@ -127,16 +127,20 @@
  				 SMBHSTSTS_BUS_ERR | SMBHSTSTS_DEV_ERR | \
  				 SMBHSTSTS_INTR)

-static unsigned long i801_smba;
-static unsigned char i801_original_hstcfg;
+struct i801_priv {
+	struct i2c_adapter adapter;
+	unsigned long smba;
+	unsigned char original_hstcfg;
+	struct pci_dev *pci_dev;
+	unsigned int features;
+};
+
  static struct pci_driver i801_driver;
-static struct pci_dev *I801_dev;

  #define FEATURE_SMBUS_PEC	(1 << 0)
  #define FEATURE_BLOCK_BUFFER	(1 << 1)
  #define FEATURE_BLOCK_PROC	(1 << 2)
  #define FEATURE_I2C_BLOCK_READ	(1 << 3)
-static unsigned int i801_features;

  static const char *i801_feature_names[] = {
  	"SMBus PEC",
@@ -151,24 +155,24 @@ MODULE_PARM_DESC(disable_features, "Disable selected driver features");

  /* 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)
+static int i801_check_pre(struct i801_priv *priv)
  {
  	int status;

-	status = inb_p(SMBHSTSTS);
+	status = inb_p(SMBHSTSTS(priv));
  	if (status & SMBHSTSTS_HOST_BUSY) {
-		dev_err(&I801_dev->dev, "SMBus is busy, can't use it!\n");
+		dev_err(&priv->pci_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",
+		dev_dbg(&priv->pci_dev->dev, "Clearing status flags (%02x)\n",
  			status);
-		outb_p(status, SMBHSTSTS);
-		status = inb_p(SMBHSTSTS) & STATUS_FLAGS;
+		outb_p(status, SMBHSTSTS(priv));
+		status = inb_p(SMBHSTSTS(priv)) & STATUS_FLAGS;
  		if (status) {
-			dev_err(&I801_dev->dev,
+			dev_err(&priv->pci_dev->dev,
  				"Failed clearing status flags (%02x)\n",
  				status);
  			return -EBUSY;
@@ -179,48 +183,48 @@ static int i801_check_pre(void)
  }

  /* Convert the status register to an error code, and clear it. */
-static int i801_check_post(int status, int timeout)
+static int i801_check_post(struct i801_priv *priv, int status, int timeout)
  {
  	int result = 0;

  	/* If the SMBus is still busy, we give up */
  	if (timeout) {
-		dev_err(&I801_dev->dev, "Transaction timeout\n");
+		dev_err(&priv->pci_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);
+		dev_dbg(&priv->pci_dev->dev, "Terminating the current operation\n");
+		outb_p(inb_p(SMBHSTCNT(priv)) | SMBHSTCNT_KILL, SMBHSTCNT(priv));
  		msleep(1);
-		outb_p(inb_p(SMBHSTCNT) & (~SMBHSTCNT_KILL), SMBHSTCNT);
+		outb_p(inb_p(SMBHSTCNT(priv)) & (~SMBHSTCNT_KILL), SMBHSTCNT(priv));

  		/* Check if it worked */
-		status = inb_p(SMBHSTSTS);
+		status = inb_p(SMBHSTSTS(priv));
  		if ((status & SMBHSTSTS_HOST_BUSY) ||
  		    !(status & SMBHSTSTS_FAILED))
-			dev_err(&I801_dev->dev,
+			dev_err(&priv->pci_dev->dev,
  				"Failed terminating the transaction\n");
-		outb_p(STATUS_FLAGS, SMBHSTSTS);
+		outb_p(STATUS_FLAGS, SMBHSTSTS(priv));
  		return -ETIMEDOUT;
  	}

  	if (status & SMBHSTSTS_FAILED) {
  		result = -EIO;
-		dev_err(&I801_dev->dev, "Transaction failed\n");
+		dev_err(&priv->pci_dev->dev, "Transaction failed\n");
  	}
  	if (status & SMBHSTSTS_DEV_ERR) {
  		result = -ENXIO;
-		dev_dbg(&I801_dev->dev, "No response\n");
+		dev_dbg(&priv->pci_dev->dev, "No response\n");
  	}
  	if (status & SMBHSTSTS_BUS_ERR) {
  		result = -EAGAIN;
-		dev_dbg(&I801_dev->dev, "Lost arbitration\n");
+		dev_dbg(&priv->pci_dev->dev, "Lost arbitration\n");
  	}

  	if (result) {
  		/* Clear error flags */
-		outb_p(status & STATUS_FLAGS, SMBHSTSTS);
-		status = inb_p(SMBHSTSTS) & STATUS_FLAGS;
+		outb_p(status & STATUS_FLAGS, SMBHSTSTS(priv));
+		status = inb_p(SMBHSTSTS(priv)) & STATUS_FLAGS;
  		if (status) {
-			dev_warn(&I801_dev->dev, "Failed clearing status "
+			dev_warn(&priv->pci_dev->dev, "Failed clearing status "
  				 "flags at end of transaction (%02x)\n",
  				 status);
  		}
@@ -229,86 +233,88 @@ static int i801_check_post(int status, int timeout)
  	return result;
  }

-static int i801_transaction(int xact)
+static int i801_transaction(struct i801_priv *priv, int xact)
  {
  	int status;
  	int result;
  	int timeout = 0;

-	result = i801_check_pre();
+	result = i801_check_pre(priv);
  	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);
+	outb_p(xact | I801_START, SMBHSTCNT(priv));

  	/* We will always wait for a fraction of a second! */
  	do {
  		msleep(1);
-		status = inb_p(SMBHSTSTS);
+		status = inb_p(SMBHSTSTS(priv));
  	} while ((status & SMBHSTSTS_HOST_BUSY) && (timeout++ < MAX_TIMEOUT));

-	result = i801_check_post(status, timeout > MAX_TIMEOUT);
+	result = i801_check_post(priv, status, timeout > MAX_TIMEOUT);
  	if (result < 0)
  		return result;

-	outb_p(SMBHSTSTS_INTR, SMBHSTSTS);
+	outb_p(SMBHSTSTS_INTR, SMBHSTSTS(priv));
  	return 0;
  }

  /* wait for INTR bit as advised by Intel */
-static void i801_wait_hwpec(void)
+static void i801_wait_hwpec(struct i801_priv *priv)
  {
  	int timeout = 0;
  	int status;

  	do {
  		msleep(1);
-		status = inb_p(SMBHSTSTS);
+		status = inb_p(SMBHSTSTS(priv));
  	} while ((!(status & SMBHSTSTS_INTR))
  		 && (timeout++ < MAX_TIMEOUT));

  	if (timeout > MAX_TIMEOUT)
-		dev_dbg(&I801_dev->dev, "PEC Timeout!\n");
+		dev_dbg(&priv->pci_dev->dev, "PEC Timeout!\n");

-	outb_p(status, SMBHSTSTS);
+	outb_p(status, SMBHSTSTS(priv));
  }

-static int i801_block_transaction_by_block(union i2c_smbus_data *data,
+static int i801_block_transaction_by_block(struct i801_priv *priv,
+					   union i2c_smbus_data *data,
  					   char read_write, int hwpec)
  {
  	int i, len;
  	int status;

-	inb_p(SMBHSTCNT); /* reset the data buffer index */
+	inb_p(SMBHSTCNT(priv)); /* reset the data buffer index */

  	/* Use 32-byte buffer to process this transaction */
  	if (read_write == I2C_SMBUS_WRITE) {
  		len = data->block[0];
-		outb_p(len, SMBHSTDAT0);
+		outb_p(len, SMBHSTDAT0(priv));
  		for (i = 0; i < len; i++)
-			outb_p(data->block[i+1], SMBBLKDAT);
+			outb_p(data->block[i+1], SMBBLKDAT(priv));
  	}

-	status = i801_transaction(I801_BLOCK_DATA | ENABLE_INT9 |
+	status = i801_transaction(priv, I801_BLOCK_DATA | ENABLE_INT9 |
  				  I801_PEC_EN * hwpec);
  	if (status)
  		return status;

  	if (read_write == I2C_SMBUS_READ) {
-		len = inb_p(SMBHSTDAT0);
+		len = inb_p(SMBHSTDAT0(priv));
  		if (len < 1 || len > I2C_SMBUS_BLOCK_MAX)
  			return -EPROTO;

  		data->block[0] = len;
  		for (i = 0; i < len; i++)
-			data->block[i + 1] = inb_p(SMBBLKDAT);
+			data->block[i + 1] = inb_p(SMBBLKDAT(priv));
  	}
  	return 0;
  }

-static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,
+static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
+					       union i2c_smbus_data *data,
  					       char read_write, int command,
  					       int hwpec)
  {
@@ -318,15 +324,15 @@ static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,
  	int result;
  	int timeout;

-	result = i801_check_pre();
+	result = i801_check_pre(priv);
  	if (result < 0)
  		return result;

  	len = data->block[0];

  	if (read_write == I2C_SMBUS_WRITE) {
-		outb_p(len, SMBHSTDAT0);
-		outb_p(data->block[1], SMBBLKDAT);
+		outb_p(len, SMBHSTDAT0(priv));
+		outb_p(data->block[1], SMBBLKDAT(priv));
  	}

  	for (i = 1; i <= len; i++) {
@@ -342,34 +348,37 @@ static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,
  			else
  				smbcmd = I801_BLOCK_DATA;
  		}
-		outb_p(smbcmd | ENABLE_INT9, SMBHSTCNT);
+		outb_p(smbcmd | ENABLE_INT9, SMBHSTCNT(priv));

  		if (i == 1)
-			outb_p(inb(SMBHSTCNT) | I801_START, SMBHSTCNT);
+			outb_p(inb(SMBHSTCNT(priv)) | I801_START,
+			       SMBHSTCNT(priv));

  		/* We will always wait for a fraction of a second! */
  		timeout = 0;
  		do {
  			msleep(1);
-			status = inb_p(SMBHSTSTS);
+			status = inb_p(SMBHSTSTS(priv));
  		} while ((!(status & SMBHSTSTS_BYTE_DONE))
  			 && (timeout++ < MAX_TIMEOUT));

-		result = i801_check_post(status, timeout > MAX_TIMEOUT);
+		result = i801_check_post(priv, 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);
+			len = inb_p(SMBHSTDAT0(priv));
  			if (len < 1 || len > I2C_SMBUS_BLOCK_MAX) {
-				dev_err(&I801_dev->dev,
+				dev_err(&priv->pci_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);
+				while (inb_p(SMBHSTSTS(priv)) &
+				       SMBHSTSTS_HOST_BUSY)
+					outb_p(SMBHSTSTS_BYTE_DONE,
+					       SMBHSTSTS(priv));
+				outb_p(SMBHSTSTS_INTR, SMBHSTSTS(priv));
  				return -EPROTO;
  			}
  			data->block[0] = len;
@@ -377,27 +386,28 @@ static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,

  		/* Retrieve/store value in SMBBLKDAT */
  		if (read_write == I2C_SMBUS_READ)
-			data->block[i] = inb_p(SMBBLKDAT);
+			data->block[i] = inb_p(SMBBLKDAT(priv));
  		if (read_write == I2C_SMBUS_WRITE && i+1 <= len)
-			outb_p(data->block[i+1], SMBBLKDAT);
+			outb_p(data->block[i+1], SMBBLKDAT(priv));

  		/* signals SMBBLKDAT ready */
-		outb_p(SMBHSTSTS_BYTE_DONE | SMBHSTSTS_INTR, SMBHSTSTS);
+		outb_p(SMBHSTSTS_BYTE_DONE | SMBHSTSTS_INTR, SMBHSTSTS(priv));
  	}

  	return 0;
  }

-static int i801_set_block_buffer_mode(void)
+static int i801_set_block_buffer_mode(struct i801_priv *priv)
  {
-	outb_p(inb_p(SMBAUXCTL) | SMBAUXCTL_E32B, SMBAUXCTL);
-	if ((inb_p(SMBAUXCTL) & SMBAUXCTL_E32B) == 0)
+	outb_p(inb_p(SMBAUXCTL(priv)) | SMBAUXCTL_E32B, SMBAUXCTL(priv));
+	if ((inb_p(SMBAUXCTL(priv)) & SMBAUXCTL_E32B) == 0)
  		return -EIO;
  	return 0;
  }

  /* Block transaction function */
-static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
+static int i801_block_transaction(struct i801_priv *priv,
+				  union i2c_smbus_data *data, char read_write,
  				  int command, int hwpec)
  {
  	int result = 0;
@@ -406,11 +416,11 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
  	if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
  		if (read_write == I2C_SMBUS_WRITE) {
  			/* set I2C_EN bit in configuration register */
-			pci_read_config_byte(I801_dev, SMBHSTCFG, &hostc);
-			pci_write_config_byte(I801_dev, SMBHSTCFG,
+			pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &hostc);
+			pci_write_config_byte(priv->pci_dev, SMBHSTCFG,
  					      hostc | SMBHSTCFG_I2C_EN);
-		} else if (!(i801_features & FEATURE_I2C_BLOCK_READ)) {
-			dev_err(&I801_dev->dev,
+		} else if (!(priv->features & FEATURE_I2C_BLOCK_READ)) {
+			dev_err(&priv->pci_dev->dev,
  				"I2C block read is unsupported!\n");
  			return -EOPNOTSUPP;
  		}
@@ -429,22 +439,23 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
  	/* Experience has shown that the block buffer can only be used for
  	   SMBus (not I2C) block transactions, even though the datasheet
  	   doesn't mention this limitation. */
-	if ((i801_features & FEATURE_BLOCK_BUFFER)
-	 && command != I2C_SMBUS_I2C_BLOCK_DATA
-	 && i801_set_block_buffer_mode() == 0)
-		result = i801_block_transaction_by_block(data, read_write,
-							 hwpec);
+	if ((priv->features & FEATURE_BLOCK_BUFFER)
+	    && command != I2C_SMBUS_I2C_BLOCK_DATA
+	    && i801_set_block_buffer_mode(priv) == 0)
+		result = i801_block_transaction_by_block(priv, data,
+							 read_write, hwpec);
  	else
-		result = i801_block_transaction_byte_by_byte(data, read_write,
+		result = i801_block_transaction_byte_by_byte(priv, data,
+							     read_write,
  							     command, hwpec);

  	if (result == 0 && hwpec)
-		i801_wait_hwpec();
+		i801_wait_hwpec(priv);

  	if (command == I2C_SMBUS_I2C_BLOCK_DATA
-	 && read_write == I2C_SMBUS_WRITE) {
+	    && read_write == I2C_SMBUS_WRITE) {
  		/* restore saved configuration register value */
-		pci_write_config_byte(I801_dev, SMBHSTCFG, hostc);
+		pci_write_config_byte(priv->pci_dev, SMBHSTCFG, hostc);
  	}
  	return result;
  }
@@ -457,81 +468,83 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,
  	int hwpec;
  	int block = 0;
  	int ret, xact = 0;
+	struct i801_priv *priv = (void *)adap;

-	hwpec = (i801_features & FEATURE_SMBUS_PEC) && (flags & I2C_CLIENT_PEC)
+	hwpec = (priv->features & FEATURE_SMBUS_PEC) && (flags & I2C_CLIENT_PEC)
  		&& size != I2C_SMBUS_QUICK
  		&& size != I2C_SMBUS_I2C_BLOCK_DATA;

  	switch (size) {
  	case I2C_SMBUS_QUICK:
  		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
-		       SMBHSTADD);
+		       SMBHSTADD(priv));
  		xact = I801_QUICK;
  		break;
  	case I2C_SMBUS_BYTE:
  		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
-		       SMBHSTADD);
+		       SMBHSTADD(priv));
  		if (read_write == I2C_SMBUS_WRITE)
-			outb_p(command, SMBHSTCMD);
+			outb_p(command, SMBHSTCMD(priv));
  		xact = I801_BYTE;
  		break;
  	case I2C_SMBUS_BYTE_DATA:
  		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
-		       SMBHSTADD);
-		outb_p(command, SMBHSTCMD);
+		       SMBHSTADD(priv));
+		outb_p(command, SMBHSTCMD(priv));
  		if (read_write == I2C_SMBUS_WRITE)
-			outb_p(data->byte, SMBHSTDAT0);
+			outb_p(data->byte, SMBHSTDAT0(priv));
  		xact = I801_BYTE_DATA;
  		break;
  	case I2C_SMBUS_WORD_DATA:
  		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
-		       SMBHSTADD);
-		outb_p(command, SMBHSTCMD);
+		       SMBHSTADD(priv));
+		outb_p(command, SMBHSTCMD(priv));
  		if (read_write == I2C_SMBUS_WRITE) {
-			outb_p(data->word & 0xff, SMBHSTDAT0);
-			outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
+			outb_p(data->word & 0xff, SMBHSTDAT0(priv));
+			outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1(priv));
  		}
  		xact = I801_WORD_DATA;
  		break;
  	case I2C_SMBUS_BLOCK_DATA:
  		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
-		       SMBHSTADD);
-		outb_p(command, SMBHSTCMD);
+		       SMBHSTADD(priv));
+		outb_p(command, SMBHSTCMD(priv));
  		block = 1;
  		break;
  	case I2C_SMBUS_I2C_BLOCK_DATA:
  		/* NB: page 240 of ICH5 datasheet shows that the R/#W
  		 * bit should be cleared here, even when reading */
-		outb_p((addr & 0x7f) << 1, SMBHSTADD);
+		outb_p((addr & 0x7f) << 1, SMBHSTADD(priv));
  		if (read_write == I2C_SMBUS_READ) {
  			/* NB: page 240 of ICH5 datasheet also shows
  			 * that DATA1 is the cmd field when reading */
-			outb_p(command, SMBHSTDAT1);
+			outb_p(command, SMBHSTDAT1(priv));
  		} else
-			outb_p(command, SMBHSTCMD);
+			outb_p(command, SMBHSTCMD(priv));
  		block = 1;
  		break;
  	default:
-		dev_err(&I801_dev->dev, "Unsupported transaction %d\n", size);
+		dev_err(&priv->pci_dev->dev, "Unsupported transaction %d\n", size);
  		return -EOPNOTSUPP;
  	}

  	if (hwpec)	/* enable/disable hardware PEC */
-		outb_p(inb_p(SMBAUXCTL) | SMBAUXCTL_CRC, SMBAUXCTL);
+		outb_p(inb_p(SMBAUXCTL(priv)) | SMBAUXCTL_CRC, SMBAUXCTL(priv));
  	else
-		outb_p(inb_p(SMBAUXCTL) & (~SMBAUXCTL_CRC), SMBAUXCTL);
+		outb_p(inb_p(SMBAUXCTL(priv)) & (~SMBAUXCTL_CRC), SMBAUXCTL(priv));

  	if (block)
-		ret = i801_block_transaction(data, read_write, size, hwpec);
+		ret = i801_block_transaction(priv, data, read_write, size,
+					     hwpec);
  	else
-		ret = i801_transaction(xact | ENABLE_INT9);
+		ret = i801_transaction(priv, xact | ENABLE_INT9);

  	/* Some BIOSes don't like it when PEC is enabled at reboot or resume
  	   time, so we forcibly disable it after every transaction. Turn off
  	   E32B for the same reason. */
  	if (hwpec || block)
-		outb_p(inb_p(SMBAUXCTL) & ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B),
-		       SMBAUXCTL);
+		outb_p(inb_p(SMBAUXCTL(priv)) & ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B),
+		       SMBAUXCTL(priv));

  	if (block)
  		return ret;
@@ -543,10 +556,11 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,
  	switch (xact & 0x7f) {
  	case I801_BYTE:	/* Result put in SMBHSTDAT0 */
  	case I801_BYTE_DATA:
-		data->byte = inb_p(SMBHSTDAT0);
+		data->byte = inb_p(SMBHSTDAT0(priv));
  		break;
  	case I801_WORD_DATA:
-		data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
+		data->word = inb_p(SMBHSTDAT0(priv)) +
+			(inb_p(SMBHSTDAT1(priv)) << 8);
  		break;
  	}
  	return 0;
@@ -555,11 +569,13 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,

  static u32 i801_func(struct i2c_adapter *adapter)
  {
+	struct i801_priv *priv = (void *)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 | I2C_FUNC_SMBUS_WRITE_I2C_BLOCK |
-	       ((i801_features & FEATURE_SMBUS_PEC) ? I2C_FUNC_SMBUS_PEC : 0) |
-	       ((i801_features & FEATURE_I2C_BLOCK_READ) ?
+	       ((priv->features & FEATURE_SMBUS_PEC) ? I2C_FUNC_SMBUS_PEC : 0) |
+	       ((priv->features & FEATURE_I2C_BLOCK_READ) ?
  		I2C_FUNC_SMBUS_READ_I2C_BLOCK : 0);
  }

@@ -568,12 +584,6 @@ static const struct i2c_algorithm smbus_algorithm = {
  	.functionality	= i801_func,
  };

-static struct i2c_adapter i801_adapter = {
-	.owner		= THIS_MODULE,
-	.class		= I2C_CLASS_HWMON | I2C_CLASS_SPD,
-	.algo		= &smbus_algorithm,
-};
-
  static const struct pci_device_id i801_ids[] = {
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AA_3) },
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AB_3) },
@@ -704,16 +714,26 @@ static int __devinit i801_probe(struct pci_dev *dev,
  {
  	unsigned char temp;
  	int err, i;
+	struct i801_priv *priv;
+
+	priv = kzalloc(sizeof (*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->adapter.owner = THIS_MODULE;
+	priv->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+	priv->adapter.algo = &smbus_algorithm;
+ 
+	priv->pci_dev = dev;
+	priv->features = 0;

-	I801_dev = dev;
-	i801_features = 0;
  	switch (dev->device) {
  	default:
-		i801_features |= FEATURE_I2C_BLOCK_READ;
+		priv->features |= FEATURE_I2C_BLOCK_READ;
  		/* fall through */
  	case PCI_DEVICE_ID_INTEL_82801DB_3:
-		i801_features |= FEATURE_SMBUS_PEC;
-		i801_features |= FEATURE_BLOCK_BUFFER;
+		priv->features |= FEATURE_SMBUS_PEC;
+		priv->features |= FEATURE_BLOCK_BUFFER;
  		/* fall through */
  	case PCI_DEVICE_ID_INTEL_82801CA_3:
  	case PCI_DEVICE_ID_INTEL_82801BA_2:
@@ -724,11 +744,11 @@ static int __devinit i801_probe(struct pci_dev *dev,

  	/* Disable features on user request */
  	for (i = 0; i < ARRAY_SIZE(i801_feature_names); i++) {
-		if (i801_features & disable_features & (1 << i))
+		if (priv->features & disable_features & (1 << i))
  			dev_notice(&dev->dev, "%s disabled by user\n",
  				   i801_feature_names[i]);
  	}
-	i801_features &= ~disable_features;
+	priv->features &= ~disable_features;

  	err = pci_enable_device(dev);
  	if (err) {
@@ -738,8 +758,8 @@ static int __devinit i801_probe(struct pci_dev *dev,
  	}

  	/* Determine the address of the SMBus area */
-	i801_smba = pci_resource_start(dev, SMBBAR);
-	if (!i801_smba) {
+	priv->smba = pci_resource_start(dev, SMBBAR);
+	if (!priv->smba) {
  		dev_err(&dev->dev, "SMBus base address uninitialized, "
  			"upgrade BIOS\n");
  		err = -ENODEV;
@@ -755,19 +775,19 @@ static int __devinit i801_probe(struct pci_dev *dev,
  	err = pci_request_region(dev, SMBBAR, i801_driver.name);
  	if (err) {
  		dev_err(&dev->dev, "Failed to request SMBus region "
-			"0x%lx-0x%Lx\n", i801_smba,
+			"0x%lx-0x%Lx\n", priv->smba,
  			(unsigned long long)pci_resource_end(dev, SMBBAR));
  		goto exit;
  	}

-	pci_read_config_byte(I801_dev, SMBHSTCFG, &temp);
-	i801_original_hstcfg = temp;
+	pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &temp);
+	priv->original_hstcfg = temp;
  	temp &= ~SMBHSTCFG_I2C_EN;	/* SMBus timing */
  	if (!(temp & SMBHSTCFG_HST_EN)) {
  		dev_info(&dev->dev, "Enabling SMBus device\n");
  		temp |= SMBHSTCFG_HST_EN;
  	}
-	pci_write_config_byte(I801_dev, SMBHSTCFG, temp);
+	pci_write_config_byte(priv->pci_dev, SMBHSTCFG, temp);

  	if (temp & SMBHSTCFG_SMB_SMI_EN)
  		dev_dbg(&dev->dev, "SMBus using interrupt SMI#\n");
@@ -775,19 +795,19 @@ static int __devinit i801_probe(struct pci_dev *dev,
  		dev_dbg(&dev->dev, "SMBus using PCI Interrupt\n");

  	/* Clear special mode bits */
-	if (i801_features & (FEATURE_SMBUS_PEC | FEATURE_BLOCK_BUFFER))
-		outb_p(inb_p(SMBAUXCTL) & ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B),
-		       SMBAUXCTL);
+	if (priv->features & (FEATURE_SMBUS_PEC | FEATURE_BLOCK_BUFFER))
+		outb_p(inb_p(SMBAUXCTL(priv)) & ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B),
+		       SMBAUXCTL(priv));

  	/* set up the sysfs linkage to our parent device */
-	i801_adapter.dev.parent = &dev->dev;
+	priv->adapter.dev.parent = &dev->dev;

  	/* Retry up to 3 times on lost arbitration */
-	i801_adapter.retries = 3;
+	priv->adapter.retries = 3;

-	snprintf(i801_adapter.name, sizeof(i801_adapter.name),
-		"SMBus I801 adapter at %04lx", i801_smba);
-	err = i2c_add_adapter(&i801_adapter);
+	snprintf(priv->adapter.name, sizeof(priv->adapter.name),
+		"SMBus I801 adapter at %04lx", priv->smba);
+	err = i2c_add_adapter(&priv->adapter);
  	if (err) {
  		dev_err(&dev->dev, "Failed to add SMBus adapter\n");
  		goto exit_release;
@@ -801,27 +821,32 @@ static int __devinit i801_probe(struct pci_dev *dev,
  		memset(&info, 0, sizeof(struct i2c_board_info));
  		info.addr = apanel_addr;
  		strlcpy(info.type, "fujitsu_apanel", I2C_NAME_SIZE);
-		i2c_new_device(&i801_adapter, &info);
+		i2c_new_device(&priv->adapter, &info);
  	}
  #endif
  #if defined CONFIG_SENSORS_FSCHMD || defined CONFIG_SENSORS_FSCHMD_MODULE
  	if (dmi_name_in_vendors("FUJITSU"))
-		dmi_walk(dmi_check_onboard_devices, &i801_adapter);
+		dmi_walk(dmi_check_onboard_devices, &priv->adapter);
  #endif
-
+	pci_set_drvdata(dev, priv);
  	return 0;

  exit_release:
  	pci_release_region(dev, SMBBAR);
  exit:
+	kfree(priv);
  	return err;
  }

  static void __devexit i801_remove(struct pci_dev *dev)
  {
-	i2c_del_adapter(&i801_adapter);
-	pci_write_config_byte(I801_dev, SMBHSTCFG, i801_original_hstcfg);
+	struct i801_priv *priv = pci_get_drvdata(dev);
+
+	i2c_del_adapter(&priv->adapter);
+	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
  	pci_release_region(dev, SMBBAR);
+	pci_set_drvdata(dev, NULL);
+	kfree(priv);
  	/*
  	 * do not call pci_disable_device(dev) since it can cause hard hangs on
  	 * some systems during power-off (eg. Fujitsu-Siemens Lifebook E8010)
@@ -831,8 +856,10 @@ static void __devexit i801_remove(struct pci_dev *dev)
  #ifdef CONFIG_PM
  static int i801_suspend(struct pci_dev *dev, pm_message_t mesg)
  {
+	struct i801_priv *priv = pci_get_drvdata(dev);
+
  	pci_save_state(dev);
-	pci_write_config_byte(dev, SMBHSTCFG, i801_original_hstcfg);
+	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
  	pci_set_power_state(dev, pci_choose_state(dev, mesg));
  	return 0;
  }
-- 
1.7.3.1


-- 
dwmw2

[PATCH 2/2] i2c-i801: Add PCI idents for Sandy Bridge SMBus controllers

[David Woodhouse]

Signed-off-by: David Woodhouse <David.Woodhouse-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
  drivers/i2c/busses/i2c-i801.c |   13 +++++++++++++
  1 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 6e8c12c..415f58d 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -45,6 +45,10 @@
    ICH10                 0x3a60     32     hard     yes     yes     yes
    5/3400 Series (PCH)   0x3b30     32     hard     yes     yes     yes
    Cougar Point (PCH)    0x1c22     32     hard     yes     yes     yes
+  Sandy Bridge (PCH)    0x1d22     32     hard     yes     yes     yes
+  Sandy Bridge (EVA)    0x1d70     32     hard     yes     yes     yes
+  Sandy Bridge (EVA)    0x1d71     32     hard     yes     yes     yes
+  Sandy Bridge (EVA)    0x1d72     32     hard     yes     yes     yes

    Features supported by this driver:
    Software PEC                     no
@@ -127,6 +131,11 @@
  				 SMBHSTSTS_BUS_ERR | SMBHSTSTS_DEV_ERR | \
  				 SMBHSTSTS_INTR)

+#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_PCH	0x1d22
+#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA1	0x1d70
+#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA2	0x1d71
+#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA3	0x1d72
+
  struct i801_priv {
  	struct i2c_adapter adapter;
  	unsigned long smba;
@@ -602,6 +611,10 @@ static const struct pci_device_id i801_ids[] = {
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH10_5) },
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS) },
  	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_PCH) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA1) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA2) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA3) },
  	{ 0, }
  };

-- 
1.7.3.1


-- 
dwmw2

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[Jean Delvare]

Hi David,

On Sat, 30 Oct 2010 14:47:56 +0100 (BST), David Woodhouse wrote:
> 

An explanation why this change is needed would be nice.

> Signed-off-by: David Woodhouse <David.Woodhouse-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> ---
>   drivers/i2c/busses/i2c-i801.c |  329 ++++++++++++++++++++++-------------------
>   1 files changed, 178 insertions(+), 151 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
> index 59d6598..6e8c12c 100644
> --- a/drivers/i2c/busses/i2c-i801.c
> +++ b/drivers/i2c/busses/i2c-i801.c
> @@ -1,8 +1,10 @@
>   /*

Note that the patch got corrupted on the way: all leading spaces have
been doubled. I had to fix it.

> -    Copyright (c) 1998 - 2002  Frodo Looijaard <frodol-B0qZmFHriGg@public.gmane.org>,
> -    Philip Edelbrock <phil-KXOFo5pg7o1l57MIdRCFDg@public.gmane.org>, and Mark D. Studebaker
> -    <mdsxyz123-/E1597aS9LQAvxtiuMwx3w@public.gmane.org>
> -    Copyright (C) 2007, 2008   Jean Delvare <khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org>
> +    Copyright © 1998 - 2002  Frodo Looijaard <frodol-B0qZmFHriGg@public.gmane.org>,
> +			     Philip Edelbrock <phil-KXOFo5pg7o1l57MIdRCFDg@public.gmane.org> and
> +			     Mark D. Studebaker <mdsxyz123-/E1597aS9LQAvxtiuMwx3w@public.gmane.org>
> +    Copyright © 2007, 2008   Jean Delvare <khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org>
> +    Copyright © 2010         Intel Corporation
> +                             David Woodhouse <dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>

I'd rather stick to (C). Using non-ASCII characters is asking for
trouble, and this doesn't add value.

> 
>       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
> @@ -54,8 +56,6 @@
>     See the file Documentation/i2c/busses/i2c-i801 for details.
>   */
> 
> -/* Note: we assume there can only be one I801, with one SMBus interface */
> -
>   #include <linux/module.h>
>   #include <linux/pci.h>
>   #include <linux/kernel.h>
> @@ -69,16 +69,16 @@
>   #include <linux/dmi.h>
> 
>   /* I801 SMBus address offsets */
> -#define SMBHSTSTS	(0 + i801_smba)
> -#define SMBHSTCNT	(2 + i801_smba)
> -#define SMBHSTCMD	(3 + i801_smba)
> -#define SMBHSTADD	(4 + i801_smba)
> -#define SMBHSTDAT0	(5 + i801_smba)
> -#define SMBHSTDAT1	(6 + i801_smba)
> -#define SMBBLKDAT	(7 + i801_smba)
> -#define SMBPEC		(8 + i801_smba)		/* ICH3 and later */
> -#define SMBAUXSTS	(12 + i801_smba)	/* ICH4 and later */
> -#define SMBAUXCTL	(13 + i801_smba)	/* ICH4 and later */
> +#define SMBHSTSTS(p)	(0 + (p)->smba)
> +#define SMBHSTCNT(p)	(2 + (p)->smba)
> +#define SMBHSTCMD(p)	(3 + (p)->smba)
> +#define SMBHSTADD(p)	(4 + (p)->smba)
> +#define SMBHSTDAT0(p)	(5 + (p)->smba)
> +#define SMBHSTDAT1(p)	(6 + (p)->smba)
> +#define SMBBLKDAT(p)	(7 + (p)->smba)
> +#define SMBPEC(p)	(8 + (p)->smba)		/* ICH3 and later */
> +#define SMBAUXSTS(p)	(12 + (p)->smba)	/* ICH4 and later */
> +#define SMBAUXCTL(p)	(13 + (p)->smba)	/* ICH4 and later */
> 
>   /* PCI Address Constants */
>   #define SMBBAR		4
> @@ -127,16 +127,20 @@
>   				 SMBHSTSTS_BUS_ERR | SMBHSTSTS_DEV_ERR | \
>   				 SMBHSTSTS_INTR)
> 
> -static unsigned long i801_smba;
> -static unsigned char i801_original_hstcfg;
> +struct i801_priv {
> +	struct i2c_adapter adapter;
> +	unsigned long smba;
> +	unsigned char original_hstcfg;
> +	struct pci_dev *pci_dev;
> +	unsigned int features;
> +};
> +
>   static struct pci_driver i801_driver;
> -static struct pci_dev *I801_dev;
> 
>   #define FEATURE_SMBUS_PEC	(1 << 0)
>   #define FEATURE_BLOCK_BUFFER	(1 << 1)
>   #define FEATURE_BLOCK_PROC	(1 << 2)
>   #define FEATURE_I2C_BLOCK_READ	(1 << 3)
> -static unsigned int i801_features;
> 
>   static const char *i801_feature_names[] = {
>   	"SMBus PEC",
> @@ -151,24 +155,24 @@ MODULE_PARM_DESC(disable_features, "Disable selected driver features");
> 
>   /* 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)
> +static int i801_check_pre(struct i801_priv *priv)
>   {
>   	int status;
> 
> -	status = inb_p(SMBHSTSTS);
> +	status = inb_p(SMBHSTSTS(priv));
>   	if (status & SMBHSTSTS_HOST_BUSY) {
> -		dev_err(&I801_dev->dev, "SMBus is busy, can't use it!\n");
> +		dev_err(&priv->pci_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",
> +		dev_dbg(&priv->pci_dev->dev, "Clearing status flags (%02x)\n",
>   			status);
> -		outb_p(status, SMBHSTSTS);
> -		status = inb_p(SMBHSTSTS) & STATUS_FLAGS;
> +		outb_p(status, SMBHSTSTS(priv));
> +		status = inb_p(SMBHSTSTS(priv)) & STATUS_FLAGS;
>   		if (status) {
> -			dev_err(&I801_dev->dev,
> +			dev_err(&priv->pci_dev->dev,
>   				"Failed clearing status flags (%02x)\n",
>   				status);
>   			return -EBUSY;
> @@ -179,48 +183,48 @@ static int i801_check_pre(void)
>   }
> 
>   /* Convert the status register to an error code, and clear it. */
> -static int i801_check_post(int status, int timeout)
> +static int i801_check_post(struct i801_priv *priv, int status, int timeout)
>   {
>   	int result = 0;
> 
>   	/* If the SMBus is still busy, we give up */
>   	if (timeout) {
> -		dev_err(&I801_dev->dev, "Transaction timeout\n");
> +		dev_err(&priv->pci_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);
> +		dev_dbg(&priv->pci_dev->dev, "Terminating the current operation\n");
> +		outb_p(inb_p(SMBHSTCNT(priv)) | SMBHSTCNT_KILL, SMBHSTCNT(priv));
>   		msleep(1);
> -		outb_p(inb_p(SMBHSTCNT) & (~SMBHSTCNT_KILL), SMBHSTCNT);
> +		outb_p(inb_p(SMBHSTCNT(priv)) & (~SMBHSTCNT_KILL), SMBHSTCNT(priv));
> 
>   		/* Check if it worked */
> -		status = inb_p(SMBHSTSTS);
> +		status = inb_p(SMBHSTSTS(priv));
>   		if ((status & SMBHSTSTS_HOST_BUSY) ||
>   		    !(status & SMBHSTSTS_FAILED))
> -			dev_err(&I801_dev->dev,
> +			dev_err(&priv->pci_dev->dev,
>   				"Failed terminating the transaction\n");
> -		outb_p(STATUS_FLAGS, SMBHSTSTS);
> +		outb_p(STATUS_FLAGS, SMBHSTSTS(priv));
>   		return -ETIMEDOUT;
>   	}
> 
>   	if (status & SMBHSTSTS_FAILED) {
>   		result = -EIO;
> -		dev_err(&I801_dev->dev, "Transaction failed\n");
> +		dev_err(&priv->pci_dev->dev, "Transaction failed\n");
>   	}
>   	if (status & SMBHSTSTS_DEV_ERR) {
>   		result = -ENXIO;
> -		dev_dbg(&I801_dev->dev, "No response\n");
> +		dev_dbg(&priv->pci_dev->dev, "No response\n");
>   	}
>   	if (status & SMBHSTSTS_BUS_ERR) {
>   		result = -EAGAIN;
> -		dev_dbg(&I801_dev->dev, "Lost arbitration\n");
> +		dev_dbg(&priv->pci_dev->dev, "Lost arbitration\n");
>   	}
> 
>   	if (result) {
>   		/* Clear error flags */
> -		outb_p(status & STATUS_FLAGS, SMBHSTSTS);
> -		status = inb_p(SMBHSTSTS) & STATUS_FLAGS;
> +		outb_p(status & STATUS_FLAGS, SMBHSTSTS(priv));
> +		status = inb_p(SMBHSTSTS(priv)) & STATUS_FLAGS;
>   		if (status) {
> -			dev_warn(&I801_dev->dev, "Failed clearing status "
> +			dev_warn(&priv->pci_dev->dev, "Failed clearing status "
>   				 "flags at end of transaction (%02x)\n",
>   				 status);
>   		}
> @@ -229,86 +233,88 @@ static int i801_check_post(int status, int timeout)
>   	return result;
>   }
> 
> -static int i801_transaction(int xact)
> +static int i801_transaction(struct i801_priv *priv, int xact)
>   {
>   	int status;
>   	int result;
>   	int timeout = 0;
> 
> -	result = i801_check_pre();
> +	result = i801_check_pre(priv);
>   	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);
> +	outb_p(xact | I801_START, SMBHSTCNT(priv));
> 
>   	/* We will always wait for a fraction of a second! */
>   	do {
>   		msleep(1);
> -		status = inb_p(SMBHSTSTS);
> +		status = inb_p(SMBHSTSTS(priv));
>   	} while ((status & SMBHSTSTS_HOST_BUSY) && (timeout++ < MAX_TIMEOUT));
> 
> -	result = i801_check_post(status, timeout > MAX_TIMEOUT);
> +	result = i801_check_post(priv, status, timeout > MAX_TIMEOUT);
>   	if (result < 0)
>   		return result;
> 
> -	outb_p(SMBHSTSTS_INTR, SMBHSTSTS);
> +	outb_p(SMBHSTSTS_INTR, SMBHSTSTS(priv));
>   	return 0;
>   }
> 
>   /* wait for INTR bit as advised by Intel */
> -static void i801_wait_hwpec(void)
> +static void i801_wait_hwpec(struct i801_priv *priv)
>   {
>   	int timeout = 0;
>   	int status;
> 
>   	do {
>   		msleep(1);
> -		status = inb_p(SMBHSTSTS);
> +		status = inb_p(SMBHSTSTS(priv));
>   	} while ((!(status & SMBHSTSTS_INTR))
>   		 && (timeout++ < MAX_TIMEOUT));
> 
>   	if (timeout > MAX_TIMEOUT)
> -		dev_dbg(&I801_dev->dev, "PEC Timeout!\n");
> +		dev_dbg(&priv->pci_dev->dev, "PEC Timeout!\n");
> 
> -	outb_p(status, SMBHSTSTS);
> +	outb_p(status, SMBHSTSTS(priv));
>   }
> 
> -static int i801_block_transaction_by_block(union i2c_smbus_data *data,
> +static int i801_block_transaction_by_block(struct i801_priv *priv,
> +					   union i2c_smbus_data *data,
>   					   char read_write, int hwpec)
>   {
>   	int i, len;
>   	int status;
> 
> -	inb_p(SMBHSTCNT); /* reset the data buffer index */
> +	inb_p(SMBHSTCNT(priv)); /* reset the data buffer index */
> 
>   	/* Use 32-byte buffer to process this transaction */
>   	if (read_write == I2C_SMBUS_WRITE) {
>   		len = data->block[0];
> -		outb_p(len, SMBHSTDAT0);
> +		outb_p(len, SMBHSTDAT0(priv));
>   		for (i = 0; i < len; i++)
> -			outb_p(data->block[i+1], SMBBLKDAT);
> +			outb_p(data->block[i+1], SMBBLKDAT(priv));
>   	}
> 
> -	status = i801_transaction(I801_BLOCK_DATA | ENABLE_INT9 |
> +	status = i801_transaction(priv, I801_BLOCK_DATA | ENABLE_INT9 |
>   				  I801_PEC_EN * hwpec);
>   	if (status)
>   		return status;
> 
>   	if (read_write == I2C_SMBUS_READ) {
> -		len = inb_p(SMBHSTDAT0);
> +		len = inb_p(SMBHSTDAT0(priv));
>   		if (len < 1 || len > I2C_SMBUS_BLOCK_MAX)
>   			return -EPROTO;
> 
>   		data->block[0] = len;
>   		for (i = 0; i < len; i++)
> -			data->block[i + 1] = inb_p(SMBBLKDAT);
> +			data->block[i + 1] = inb_p(SMBBLKDAT(priv));
>   	}
>   	return 0;
>   }
> 
> -static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,
> +static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
> +					       union i2c_smbus_data *data,
>   					       char read_write, int command,
>   					       int hwpec)
>   {
> @@ -318,15 +324,15 @@ static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,
>   	int result;
>   	int timeout;
> 
> -	result = i801_check_pre();
> +	result = i801_check_pre(priv);
>   	if (result < 0)
>   		return result;
> 
>   	len = data->block[0];
> 
>   	if (read_write == I2C_SMBUS_WRITE) {
> -		outb_p(len, SMBHSTDAT0);
> -		outb_p(data->block[1], SMBBLKDAT);
> +		outb_p(len, SMBHSTDAT0(priv));
> +		outb_p(data->block[1], SMBBLKDAT(priv));
>   	}
> 
>   	for (i = 1; i <= len; i++) {
> @@ -342,34 +348,37 @@ static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,
>   			else
>   				smbcmd = I801_BLOCK_DATA;
>   		}
> -		outb_p(smbcmd | ENABLE_INT9, SMBHSTCNT);
> +		outb_p(smbcmd | ENABLE_INT9, SMBHSTCNT(priv));
> 
>   		if (i == 1)
> -			outb_p(inb(SMBHSTCNT) | I801_START, SMBHSTCNT);
> +			outb_p(inb(SMBHSTCNT(priv)) | I801_START,
> +			       SMBHSTCNT(priv));
> 
>   		/* We will always wait for a fraction of a second! */
>   		timeout = 0;
>   		do {
>   			msleep(1);
> -			status = inb_p(SMBHSTSTS);
> +			status = inb_p(SMBHSTSTS(priv));
>   		} while ((!(status & SMBHSTSTS_BYTE_DONE))
>   			 && (timeout++ < MAX_TIMEOUT));
> 
> -		result = i801_check_post(status, timeout > MAX_TIMEOUT);
> +		result = i801_check_post(priv, 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);
> +			len = inb_p(SMBHSTDAT0(priv));
>   			if (len < 1 || len > I2C_SMBUS_BLOCK_MAX) {
> -				dev_err(&I801_dev->dev,
> +				dev_err(&priv->pci_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);
> +				while (inb_p(SMBHSTSTS(priv)) &
> +				       SMBHSTSTS_HOST_BUSY)
> +					outb_p(SMBHSTSTS_BYTE_DONE,
> +					       SMBHSTSTS(priv));
> +				outb_p(SMBHSTSTS_INTR, SMBHSTSTS(priv));
>   				return -EPROTO;
>   			}
>   			data->block[0] = len;
> @@ -377,27 +386,28 @@ static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,
> 
>   		/* Retrieve/store value in SMBBLKDAT */
>   		if (read_write == I2C_SMBUS_READ)
> -			data->block[i] = inb_p(SMBBLKDAT);
> +			data->block[i] = inb_p(SMBBLKDAT(priv));
>   		if (read_write == I2C_SMBUS_WRITE && i+1 <= len)
> -			outb_p(data->block[i+1], SMBBLKDAT);
> +			outb_p(data->block[i+1], SMBBLKDAT(priv));
> 
>   		/* signals SMBBLKDAT ready */
> -		outb_p(SMBHSTSTS_BYTE_DONE | SMBHSTSTS_INTR, SMBHSTSTS);
> +		outb_p(SMBHSTSTS_BYTE_DONE | SMBHSTSTS_INTR, SMBHSTSTS(priv));
>   	}
> 
>   	return 0;
>   }
> 
> -static int i801_set_block_buffer_mode(void)
> +static int i801_set_block_buffer_mode(struct i801_priv *priv)
>   {
> -	outb_p(inb_p(SMBAUXCTL) | SMBAUXCTL_E32B, SMBAUXCTL);
> -	if ((inb_p(SMBAUXCTL) & SMBAUXCTL_E32B) == 0)
> +	outb_p(inb_p(SMBAUXCTL(priv)) | SMBAUXCTL_E32B, SMBAUXCTL(priv));
> +	if ((inb_p(SMBAUXCTL(priv)) & SMBAUXCTL_E32B) == 0)
>   		return -EIO;
>   	return 0;
>   }
> 
>   /* Block transaction function */
> -static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
> +static int i801_block_transaction(struct i801_priv *priv,
> +				  union i2c_smbus_data *data, char read_write,
>   				  int command, int hwpec)
>   {
>   	int result = 0;
> @@ -406,11 +416,11 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
>   	if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
>   		if (read_write == I2C_SMBUS_WRITE) {
>   			/* set I2C_EN bit in configuration register */
> -			pci_read_config_byte(I801_dev, SMBHSTCFG, &hostc);
> -			pci_write_config_byte(I801_dev, SMBHSTCFG,
> +			pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &hostc);
> +			pci_write_config_byte(priv->pci_dev, SMBHSTCFG,
>   					      hostc | SMBHSTCFG_I2C_EN);
> -		} else if (!(i801_features & FEATURE_I2C_BLOCK_READ)) {
> -			dev_err(&I801_dev->dev,
> +		} else if (!(priv->features & FEATURE_I2C_BLOCK_READ)) {
> +			dev_err(&priv->pci_dev->dev,
>   				"I2C block read is unsupported!\n");
>   			return -EOPNOTSUPP;
>   		}
> @@ -429,22 +439,23 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
>   	/* Experience has shown that the block buffer can only be used for
>   	   SMBus (not I2C) block transactions, even though the datasheet
>   	   doesn't mention this limitation. */
> -	if ((i801_features & FEATURE_BLOCK_BUFFER)
> -	 && command != I2C_SMBUS_I2C_BLOCK_DATA
> -	 && i801_set_block_buffer_mode() == 0)
> -		result = i801_block_transaction_by_block(data, read_write,
> -							 hwpec);
> +	if ((priv->features & FEATURE_BLOCK_BUFFER)
> +	    && command != I2C_SMBUS_I2C_BLOCK_DATA
> +	    && i801_set_block_buffer_mode(priv) == 0)

Gratuitous reindentation of code.

> +		result = i801_block_transaction_by_block(priv, data,
> +							 read_write, hwpec);
>   	else
> -		result = i801_block_transaction_byte_by_byte(data, read_write,
> +		result = i801_block_transaction_byte_by_byte(priv, data,
> +							     read_write,
>   							     command, hwpec);
> 
>   	if (result == 0 && hwpec)
> -		i801_wait_hwpec();
> +		i801_wait_hwpec(priv);
> 
>   	if (command == I2C_SMBUS_I2C_BLOCK_DATA
> -	 && read_write == I2C_SMBUS_WRITE) {
> +	    && read_write == I2C_SMBUS_WRITE) {

Ditto.

>   		/* restore saved configuration register value */
> -		pci_write_config_byte(I801_dev, SMBHSTCFG, hostc);
> +		pci_write_config_byte(priv->pci_dev, SMBHSTCFG, hostc);
>   	}
>   	return result;
>   }
> @@ -457,81 +468,83 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,
>   	int hwpec;
>   	int block = 0;
>   	int ret, xact = 0;
> +	struct i801_priv *priv = (void *)adap;

This is horrible and only works by accident (or misdesign if you
prefer). Please don't do this. I'm glad I insisted to review this
patch...

We have i2c_set/get_adapdata() for this. If you really care about the
extra cost, please use the proper container_of() construct. But I don't
think the cost is problematic.

> 
> -	hwpec = (i801_features & FEATURE_SMBUS_PEC) && (flags & I2C_CLIENT_PEC)
> +	hwpec = (priv->features & FEATURE_SMBUS_PEC) && (flags & I2C_CLIENT_PEC)
>   		&& size != I2C_SMBUS_QUICK
>   		&& size != I2C_SMBUS_I2C_BLOCK_DATA;
> 
>   	switch (size) {
>   	case I2C_SMBUS_QUICK:
>   		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
> -		       SMBHSTADD);
> +		       SMBHSTADD(priv));
>   		xact = I801_QUICK;
>   		break;
>   	case I2C_SMBUS_BYTE:
>   		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
> -		       SMBHSTADD);
> +		       SMBHSTADD(priv));
>   		if (read_write == I2C_SMBUS_WRITE)
> -			outb_p(command, SMBHSTCMD);
> +			outb_p(command, SMBHSTCMD(priv));
>   		xact = I801_BYTE;
>   		break;
>   	case I2C_SMBUS_BYTE_DATA:
>   		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
> -		       SMBHSTADD);
> -		outb_p(command, SMBHSTCMD);
> +		       SMBHSTADD(priv));
> +		outb_p(command, SMBHSTCMD(priv));
>   		if (read_write == I2C_SMBUS_WRITE)
> -			outb_p(data->byte, SMBHSTDAT0);
> +			outb_p(data->byte, SMBHSTDAT0(priv));
>   		xact = I801_BYTE_DATA;
>   		break;
>   	case I2C_SMBUS_WORD_DATA:
>   		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
> -		       SMBHSTADD);
> -		outb_p(command, SMBHSTCMD);
> +		       SMBHSTADD(priv));
> +		outb_p(command, SMBHSTCMD(priv));
>   		if (read_write == I2C_SMBUS_WRITE) {
> -			outb_p(data->word & 0xff, SMBHSTDAT0);
> -			outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
> +			outb_p(data->word & 0xff, SMBHSTDAT0(priv));
> +			outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1(priv));
>   		}
>   		xact = I801_WORD_DATA;
>   		break;
>   	case I2C_SMBUS_BLOCK_DATA:
>   		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
> -		       SMBHSTADD);
> -		outb_p(command, SMBHSTCMD);
> +		       SMBHSTADD(priv));
> +		outb_p(command, SMBHSTCMD(priv));
>   		block = 1;
>   		break;
>   	case I2C_SMBUS_I2C_BLOCK_DATA:
>   		/* NB: page 240 of ICH5 datasheet shows that the R/#W
>   		 * bit should be cleared here, even when reading */
> -		outb_p((addr & 0x7f) << 1, SMBHSTADD);
> +		outb_p((addr & 0x7f) << 1, SMBHSTADD(priv));
>   		if (read_write == I2C_SMBUS_READ) {
>   			/* NB: page 240 of ICH5 datasheet also shows
>   			 * that DATA1 is the cmd field when reading */
> -			outb_p(command, SMBHSTDAT1);
> +			outb_p(command, SMBHSTDAT1(priv));
>   		} else
> -			outb_p(command, SMBHSTCMD);
> +			outb_p(command, SMBHSTCMD(priv));
>   		block = 1;
>   		break;
>   	default:
> -		dev_err(&I801_dev->dev, "Unsupported transaction %d\n", size);
> +		dev_err(&priv->pci_dev->dev, "Unsupported transaction %d\n", size);
>   		return -EOPNOTSUPP;
>   	}
> 
>   	if (hwpec)	/* enable/disable hardware PEC */
> -		outb_p(inb_p(SMBAUXCTL) | SMBAUXCTL_CRC, SMBAUXCTL);
> +		outb_p(inb_p(SMBAUXCTL(priv)) | SMBAUXCTL_CRC, SMBAUXCTL(priv));
>   	else
> -		outb_p(inb_p(SMBAUXCTL) & (~SMBAUXCTL_CRC), SMBAUXCTL);
> +		outb_p(inb_p(SMBAUXCTL(priv)) & (~SMBAUXCTL_CRC), SMBAUXCTL(priv));
> 
>   	if (block)
> -		ret = i801_block_transaction(data, read_write, size, hwpec);
> +		ret = i801_block_transaction(priv, data, read_write, size,
> +					     hwpec);
>   	else
> -		ret = i801_transaction(xact | ENABLE_INT9);
> +		ret = i801_transaction(priv, xact | ENABLE_INT9);
> 
>   	/* Some BIOSes don't like it when PEC is enabled at reboot or resume
>   	   time, so we forcibly disable it after every transaction. Turn off
>   	   E32B for the same reason. */
>   	if (hwpec || block)
> -		outb_p(inb_p(SMBAUXCTL) & ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B),
> -		       SMBAUXCTL);
> +		outb_p(inb_p(SMBAUXCTL(priv)) & ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B),
> +		       SMBAUXCTL(priv));
> 
>   	if (block)
>   		return ret;
> @@ -543,10 +556,11 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,
>   	switch (xact & 0x7f) {
>   	case I801_BYTE:	/* Result put in SMBHSTDAT0 */
>   	case I801_BYTE_DATA:
> -		data->byte = inb_p(SMBHSTDAT0);
> +		data->byte = inb_p(SMBHSTDAT0(priv));
>   		break;
>   	case I801_WORD_DATA:
> -		data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
> +		data->word = inb_p(SMBHSTDAT0(priv)) +
> +			(inb_p(SMBHSTDAT1(priv)) << 8);

Please align.

>   		break;
>   	}
>   	return 0;
> @@ -555,11 +569,13 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,
> 
>   static u32 i801_func(struct i2c_adapter *adapter)
>   {
> +	struct i801_priv *priv = (void *)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 | I2C_FUNC_SMBUS_WRITE_I2C_BLOCK |
> -	       ((i801_features & FEATURE_SMBUS_PEC) ? I2C_FUNC_SMBUS_PEC : 0) |
> -	       ((i801_features & FEATURE_I2C_BLOCK_READ) ?
> +	       ((priv->features & FEATURE_SMBUS_PEC) ? I2C_FUNC_SMBUS_PEC : 0) |
> +	       ((priv->features & FEATURE_I2C_BLOCK_READ) ?
>   		I2C_FUNC_SMBUS_READ_I2C_BLOCK : 0);
>   }
> 
> @@ -568,12 +584,6 @@ static const struct i2c_algorithm smbus_algorithm = {
>   	.functionality	= i801_func,
>   };
> 
> -static struct i2c_adapter i801_adapter = {
> -	.owner		= THIS_MODULE,
> -	.class		= I2C_CLASS_HWMON | I2C_CLASS_SPD,
> -	.algo		= &smbus_algorithm,
> -};
> -
>   static const struct pci_device_id i801_ids[] = {
>   	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AA_3) },
>   	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AB_3) },
> @@ -704,16 +714,26 @@ static int __devinit i801_probe(struct pci_dev *dev,
>   {
>   	unsigned char temp;
>   	int err, i;
> +	struct i801_priv *priv;
> +
> +	priv = kzalloc(sizeof (*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	priv->adapter.owner = THIS_MODULE;
> +	priv->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
> +	priv->adapter.algo = &smbus_algorithm;
> + 
> +	priv->pci_dev = dev;
> +	priv->features = 0;

You just kzalloc'd the structure, so features are already 0.

> 
> -	I801_dev = dev;
> -	i801_features = 0;
>   	switch (dev->device) {
>   	default:
> -		i801_features |= FEATURE_I2C_BLOCK_READ;
> +		priv->features |= FEATURE_I2C_BLOCK_READ;
>   		/* fall through */
>   	case PCI_DEVICE_ID_INTEL_82801DB_3:
> -		i801_features |= FEATURE_SMBUS_PEC;
> -		i801_features |= FEATURE_BLOCK_BUFFER;
> +		priv->features |= FEATURE_SMBUS_PEC;
> +		priv->features |= FEATURE_BLOCK_BUFFER;
>   		/* fall through */
>   	case PCI_DEVICE_ID_INTEL_82801CA_3:
>   	case PCI_DEVICE_ID_INTEL_82801BA_2:
> @@ -724,11 +744,11 @@ static int __devinit i801_probe(struct pci_dev *dev,
> 
>   	/* Disable features on user request */
>   	for (i = 0; i < ARRAY_SIZE(i801_feature_names); i++) {
> -		if (i801_features & disable_features & (1 << i))
> +		if (priv->features & disable_features & (1 << i))
>   			dev_notice(&dev->dev, "%s disabled by user\n",
>   				   i801_feature_names[i]);
>   	}
> -	i801_features &= ~disable_features;
> +	priv->features &= ~disable_features;
> 
>   	err = pci_enable_device(dev);
>   	if (err) {
> @@ -738,8 +758,8 @@ static int __devinit i801_probe(struct pci_dev *dev,
>   	}
> 
>   	/* Determine the address of the SMBus area */
> -	i801_smba = pci_resource_start(dev, SMBBAR);
> -	if (!i801_smba) {
> +	priv->smba = pci_resource_start(dev, SMBBAR);
> +	if (!priv->smba) {
>   		dev_err(&dev->dev, "SMBus base address uninitialized, "
>   			"upgrade BIOS\n");
>   		err = -ENODEV;
> @@ -755,19 +775,19 @@ static int __devinit i801_probe(struct pci_dev *dev,
>   	err = pci_request_region(dev, SMBBAR, i801_driver.name);
>   	if (err) {
>   		dev_err(&dev->dev, "Failed to request SMBus region "
> -			"0x%lx-0x%Lx\n", i801_smba,
> +			"0x%lx-0x%Lx\n", priv->smba,
>   			(unsigned long long)pci_resource_end(dev, SMBBAR));
>   		goto exit;
>   	}
> 
> -	pci_read_config_byte(I801_dev, SMBHSTCFG, &temp);
> -	i801_original_hstcfg = temp;
> +	pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &temp);
> +	priv->original_hstcfg = temp;
>   	temp &= ~SMBHSTCFG_I2C_EN;	/* SMBus timing */
>   	if (!(temp & SMBHSTCFG_HST_EN)) {
>   		dev_info(&dev->dev, "Enabling SMBus device\n");
>   		temp |= SMBHSTCFG_HST_EN;
>   	}
> -	pci_write_config_byte(I801_dev, SMBHSTCFG, temp);
> +	pci_write_config_byte(priv->pci_dev, SMBHSTCFG, temp);
> 
>   	if (temp & SMBHSTCFG_SMB_SMI_EN)
>   		dev_dbg(&dev->dev, "SMBus using interrupt SMI#\n");
> @@ -775,19 +795,19 @@ static int __devinit i801_probe(struct pci_dev *dev,
>   		dev_dbg(&dev->dev, "SMBus using PCI Interrupt\n");
> 
>   	/* Clear special mode bits */
> -	if (i801_features & (FEATURE_SMBUS_PEC | FEATURE_BLOCK_BUFFER))
> -		outb_p(inb_p(SMBAUXCTL) & ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B),
> -		       SMBAUXCTL);
> +	if (priv->features & (FEATURE_SMBUS_PEC | FEATURE_BLOCK_BUFFER))
> +		outb_p(inb_p(SMBAUXCTL(priv)) & ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B),
> +		       SMBAUXCTL(priv));
> 
>   	/* set up the sysfs linkage to our parent device */
> -	i801_adapter.dev.parent = &dev->dev;
> +	priv->adapter.dev.parent = &dev->dev;
> 
>   	/* Retry up to 3 times on lost arbitration */
> -	i801_adapter.retries = 3;
> +	priv->adapter.retries = 3;
> 
> -	snprintf(i801_adapter.name, sizeof(i801_adapter.name),
> -		"SMBus I801 adapter at %04lx", i801_smba);
> -	err = i2c_add_adapter(&i801_adapter);
> +	snprintf(priv->adapter.name, sizeof(priv->adapter.name),
> +		"SMBus I801 adapter at %04lx", priv->smba);
> +	err = i2c_add_adapter(&priv->adapter);
>   	if (err) {
>   		dev_err(&dev->dev, "Failed to add SMBus adapter\n");
>   		goto exit_release;
> @@ -801,27 +821,32 @@ static int __devinit i801_probe(struct pci_dev *dev,
>   		memset(&info, 0, sizeof(struct i2c_board_info));
>   		info.addr = apanel_addr;
>   		strlcpy(info.type, "fujitsu_apanel", I2C_NAME_SIZE);
> -		i2c_new_device(&i801_adapter, &info);
> +		i2c_new_device(&priv->adapter, &info);
>   	}
>   #endif
>   #if defined CONFIG_SENSORS_FSCHMD || defined CONFIG_SENSORS_FSCHMD_MODULE
>   	if (dmi_name_in_vendors("FUJITSU"))
> -		dmi_walk(dmi_check_onboard_devices, &i801_adapter);
> +		dmi_walk(dmi_check_onboard_devices, &priv->adapter);
>   #endif
> -

Please leave this blank line in place.

> +	pci_set_drvdata(dev, priv);
>   	return 0;
> 
>   exit_release:
>   	pci_release_region(dev, SMBBAR);
>   exit:
> +	kfree(priv);
>   	return err;
>   }
> 
>   static void __devexit i801_remove(struct pci_dev *dev)
>   {
> -	i2c_del_adapter(&i801_adapter);
> -	pci_write_config_byte(I801_dev, SMBHSTCFG, i801_original_hstcfg);
> +	struct i801_priv *priv = pci_get_drvdata(dev);
> +
> +	i2c_del_adapter(&priv->adapter);
> +	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
>   	pci_release_region(dev, SMBBAR);
> +	pci_set_drvdata(dev, NULL);
> +	kfree(priv);
>   	/*
>   	 * do not call pci_disable_device(dev) since it can cause hard hangs on
>   	 * some systems during power-off (eg. Fujitsu-Siemens Lifebook E8010)
> @@ -831,8 +856,10 @@ static void __devexit i801_remove(struct pci_dev *dev)
>   #ifdef CONFIG_PM
>   static int i801_suspend(struct pci_dev *dev, pm_message_t mesg)
>   {
> +	struct i801_priv *priv = pci_get_drvdata(dev);
> +
>   	pci_save_state(dev);
> -	pci_write_config_byte(dev, SMBHSTCFG, i801_original_hstcfg);
> +	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
>   	pci_set_power_state(dev, pci_choose_state(dev, mesg));
>   	return 0;
>   }

Patch tested OK on ICH10.

-- 
Jean Delvare

Re: [PATCH 2/2] i2c-i801: Add PCI idents for Sandy Bridge SMBus controllers

[Jean Delvare]

On Sat, 30 Oct 2010 14:49:31 +0100 (BST), David Woodhouse wrote:
> 
> Signed-off-by: David Woodhouse <David.Woodhouse-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> ---
>   drivers/i2c/busses/i2c-i801.c |   13 +++++++++++++
>   1 files changed, 13 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
> index 6e8c12c..415f58d 100644
> --- a/drivers/i2c/busses/i2c-i801.c
> +++ b/drivers/i2c/busses/i2c-i801.c
> @@ -45,6 +45,10 @@
>     ICH10                 0x3a60     32     hard     yes     yes     yes
>     5/3400 Series (PCH)   0x3b30     32     hard     yes     yes     yes
>     Cougar Point (PCH)    0x1c22     32     hard     yes     yes     yes
> +  Sandy Bridge (PCH)    0x1d22     32     hard     yes     yes     yes
> +  Sandy Bridge (EVA)    0x1d70     32     hard     yes     yes     yes
> +  Sandy Bridge (EVA)    0x1d71     32     hard     yes     yes     yes
> +  Sandy Bridge (EVA)    0x1d72     32     hard     yes     yes     yes

This doesn't apply, because of the following pending patch which is
also adding support for a new driver (so touching the exact same areas
of the driver):
ftp://ftp.kernel.org/pub/linux/kernel/people/jdelvare/linux-2.6/jdelvare-i2c/i2c-i801-add-intel-patsburg-device-id.patch

As a side note, I really don't get the point of using 4 different PCI
device IDs for exactly the same device. Intel should really start to
worry about their numbering space if they keep attributing IDs when
they don't need to. 16 bit is fast to exhaust...

> 
>     Features supported by this driver:
>     Software PEC                     no
> @@ -127,6 +131,11 @@
>   				 SMBHSTSTS_BUS_ERR | SMBHSTSTS_DEV_ERR | \
>   				 SMBHSTSTS_INTR)
> 
> +#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_PCH	0x1d22
> +#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA1	0x1d70
> +#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA2	0x1d71
> +#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA3	0x1d72
> +

These should go to pci_ids.h together with all other similar defines.

>   struct i801_priv {
>   	struct i2c_adapter adapter;
>   	unsigned long smba;
> @@ -602,6 +611,10 @@ static const struct pci_device_id i801_ids[] = {
>   	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH10_5) },
>   	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS) },
>   	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS) },
> +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_PCH) },
> +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA1) },
> +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA2) },
> +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA3) },
>   	{ 0, }
>   };
> 

You also have to list the new device in drivers/i2c/busses/Kconfig and
Documentation/i2c/busses/i2c-i801.

-- 
Jean Delvare

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[Ben Dooks]

On Sat, Oct 30, 2010 at 06:24:58PM +0200, Jean Delvare wrote:
> Hi David,
> 
> On Sat, 30 Oct 2010 14:47:56 +0100 (BST), David Woodhouse wrote:
> > 
> 
> An explanation why this change is needed would be nice.
> 
> > Signed-off-by: David Woodhouse <David.Woodhouse-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> > ---
> >   drivers/i2c/busses/i2c-i801.c |  329 ++++++++++++++++++++++-------------------
> >   1 files changed, 178 insertions(+), 151 deletions(-)
> > 
> > diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
> > index 59d6598..6e8c12c 100644
> > --- a/drivers/i2c/busses/i2c-i801.c
> > +++ b/drivers/i2c/busses/i2c-i801.c
> > @@ -1,8 +1,10 @@
> >   /*
> 
> Note that the patch got corrupted on the way: all leading spaces have
> been doubled. I had to fix it.
> 
> > -    Copyright (c) 1998 - 2002  Frodo Looijaard <frodol-B0qZmFHriGg@public.gmane.org>,
> > -    Philip Edelbrock <phil-KXOFo5pg7o1l57MIdRCFDg@public.gmane.org>, and Mark D. Studebaker
> > -    <mdsxyz123-/E1597aS9LQAvxtiuMwx3w@public.gmane.org>
> > -    Copyright (C) 2007, 2008   Jean Delvare <khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org>
> > +    Copyright © 1998 - 2002  Frodo Looijaard <frodol-B0qZmFHriGg@public.gmane.org>,
> > +			     Philip Edelbrock <phil-KXOFo5pg7o1l57MIdRCFDg@public.gmane.org> and
> > +			     Mark D. Studebaker <mdsxyz123-/E1597aS9LQAvxtiuMwx3w@public.gmane.org>
> > +    Copyright © 2007, 2008   Jean Delvare <khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org>
> > +    Copyright © 2010         Intel Corporation
> > +                             David Woodhouse <dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
> 
> I'd rather stick to (C). Using non-ASCII characters is asking for
> trouble, and this doesn't add value.

IIRC, and IANAL, (C) is not sufficient in certain areas (such as the UK)
to declare copyright. It needs to be either the word Copyright in full,
or the proper 'c' in circle. Both is of coures better.
 
[snip]

-- 
Ben

Q:      What's a light-year?
A:      One-third less calories than a regular year.

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[David Woodhouse]

On Sun, 2010-10-31 at 00:00 +0100, Ben Dooks wrote:
> 
> > I'd rather stick to (C). Using non-ASCII characters is asking for
> > trouble, and this doesn't add value.
> 
> IIRC, and IANAL, (C) is not sufficient in certain areas (such as the UK)
> to declare copyright. It needs to be either the word Copyright in full,
> or the proper 'c' in circle. Both is of coures better. 

This is the 21st century — we really don't have to stick to ASCII any
more.

-- 
dwmw2

Re: [PATCH 2/2] i2c-i801: Add PCI idents for Sandy Bridge SMBus controllers

[David Woodhouse]

On Sat, 2010-10-30 at 18:36 +0200, Jean Delvare wrote:
> As a side note, I really don't get the point of using 4 different PCI
> device IDs for exactly the same device. Intel should really start to
> worry about their numbering space if they keep attributing IDs when
> they don't need to. 16 bit is fast to exhaust...

Don't we keep buying companies that have their own PCI vendor ID? :)

I certainly agree about the 0x1d7[012] IDs -- those seem fairly
gratuitous. The main one (0x1d22) lacks slave mode though, so it is
different from the others. Not that we care right now.

> > 
> >     Features supported by this driver:
> >     Software PEC                     no
> > @@ -127,6 +131,11 @@
> >   				 SMBHSTSTS_BUS_ERR | SMBHSTSTS_DEV_ERR | \
> >   				 SMBHSTSTS_INTR)
> > 
> > +#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_PCH	0x1d22
> > +#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA1	0x1d70
> > +#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA2	0x1d71
> > +#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA3	0x1d72
> > +
> 
> These should go to pci_ids.h together with all other similar defines.

 *      Do not add new entries to this file unless the definitions
 *      are shared between multiple drivers.


> >   struct i801_priv {
> >   	struct i2c_adapter adapter;
> >   	unsigned long smba;
> > @@ -602,6 +611,10 @@ static const struct pci_device_id i801_ids[] = {
> >   	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH10_5) },
> >   	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS) },
> >   	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS) },
> > +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_PCH) },
> > +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA1) },
> > +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA2) },
> > +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA3) },
> >   	{ 0, }
> >   };
> > 
> 
> You also have to list the new device in drivers/i2c/busses/Kconfig and
> Documentation/i2c/busses/i2c-i801.

Will update.

-- 
David Woodhouse                            Open Source Technology Centre
David.Woodhouse-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org                              Intel Corporation

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[David Woodhouse]

On Sat, 2010-10-30 at 18:24 +0200, Jean Delvare wrote:
> An explanation why this change is needed would be nice.

Um, does it really need explaining? It's really poor form to keep driver
state in global variables rather than per-instance, even if you *don't*
actually have more than one device.

> Note that the patch got corrupted on the way: all leading spaces have
> been doubled. I had to fix it.

Sorry about that. Was sending from my phone, as I said before.

> > +    Copyright © 2010         Intel Corporation
> > +                             David Woodhouse <dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
> 
> I'd rather stick to (C). Using non-ASCII characters is asking for
> trouble, and this doesn't add value.

It really isn't trouble. We're well into the 21st century now — even
akpm can cope with UTF-8 :)
 
> > @@ -429,22 +439,23 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
> >   	/* Experience has shown that the block buffer can only be used for
> >   	   SMBus (not I2C) block transactions, even though the datasheet
> >   	   doesn't mention this limitation. */
> > -	if ((i801_features & FEATURE_BLOCK_BUFFER)
> > -	 && command != I2C_SMBUS_I2C_BLOCK_DATA
> > -	 && i801_set_block_buffer_mode() == 0)
> > -		result = i801_block_transaction_by_block(data, read_write,
> > -							 hwpec);
> > +	if ((priv->features & FEATURE_BLOCK_BUFFER)
> > +	    && command != I2C_SMBUS_I2C_BLOCK_DATA
> > +	    && i801_set_block_buffer_mode(priv) == 0)
> 
> Gratuitous reindentation of code.

The two continuation lines? I just fixed them to conform to the normal
kernel indentation, while I was modifying the lines before and after.
That's entirely normal practice, and not particularly gratuitous,
surely?

> > @@ -457,81 +468,83 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,
> >   	int hwpec;
> >   	int block = 0;
> >   	int ret, xact = 0;
> > +	struct i801_priv *priv = (void *)adap;
> 
> This is horrible and only works by accident (or misdesign if you
> prefer). Please don't do this. I'm glad I insisted to review this
> patch...
> 
> We have i2c_set/get_adapdata() for this. If you really care about the
> extra cost, please use the proper container_of() construct. But I don't
> think the cost is problematic.

It wasn't the cost I was thinking of; it was the simplicity. One
allocation, one failure case, one error path. That's why this method is
fairly common within the kernel.

However, I have no particular objection to doing separate allocations,
even though it's not what I'd normally do. I'll send another version.

> >   	switch (xact & 0x7f) {
> >   	case I801_BYTE:	/* Result put in SMBHSTDAT0 */
> >   	case I801_BYTE_DATA:
> > -		data->byte = inb_p(SMBHSTDAT0);
> > +		data->byte = inb_p(SMBHSTDAT0(priv));
> >   		break;
> >   	case I801_WORD_DATA:
> > -		data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
> > +		data->word = inb_p(SMBHSTDAT0(priv)) +
> > +			(inb_p(SMBHSTDAT1(priv)) << 8);
> 
> Please align.

Yeah, I remember wondering why emacs put it there, but figured I'd trust
it :)

> > +	priv->features = 0;
> 
> You just kzalloc'd the structure, so features are already 0.

True.

> > @@ -801,27 +821,32 @@ static int __devinit i801_probe(struct pci_dev *dev,
> >   		memset(&info, 0, sizeof(struct i2c_board_info));
> >   		info.addr = apanel_addr;
> >   		strlcpy(info.type, "fujitsu_apanel", I2C_NAME_SIZE);
> > -		i2c_new_device(&i801_adapter, &info);
> > +		i2c_new_device(&priv->adapter, &info);
> >   	}
> >   #endif
> >   #if defined CONFIG_SENSORS_FSCHMD || defined CONFIG_SENSORS_FSCHMD_MODULE
> >   	if (dmi_name_in_vendors("FUJITSU"))
> > -		dmi_walk(dmi_check_onboard_devices, &i801_adapter);
> > +		dmi_walk(dmi_check_onboard_devices, &priv->adapter);
> >   #endif
> > -
> 
> Please leave this blank line in place.

Um, OK.

> Patch tested OK on ICH10.

Cool, thanks. I'll send an updated patch; hopefully later this evening.

-- 
David Woodhouse                            Open Source Technology Centre
David.Woodhouse-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org                              Intel Corporation

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[Ben Dooks]

On Sat, Oct 30, 2010 at 07:34:23PM -0400, David Woodhouse wrote:
> On Sat, 2010-10-30 at 18:24 +0200, Jean Delvare wrote:
> > An explanation why this change is needed would be nice.
> 
> Um, does it really need explaining? It's really poor form to keep driver
> state in global variables rather than per-instance, even if you *don't*
> actually have more than one device.

I always like to fill it in, it makes it easier for lazy folks who can't
be bothered to read the patch itself.
 
> It really isn't trouble. We're well into the 21st century now ??? even
> akpm can cope with UTF-8 :)

I'd have to check what the kernel's default charset is...

-- 
Ben

Q:      What's a light-year?
A:      One-third less calories than a regular year.

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[David Woodhouse]

On Sun, 2010-10-31 at 00:39 +0100, Ben Dooks wrote:
> On Sat, Oct 30, 2010 at 07:34:23PM -0400, David Woodhouse wrote:
> > On Sat, 2010-10-30 at 18:24 +0200, Jean Delvare wrote:
> > > An explanation why this change is needed would be nice.
> > 
> > Um, does it really need explaining? It's really poor form to keep driver
> > state in global variables rather than per-instance, even if you *don't*
> > actually have more than one device.
> 
> I always like to fill it in, it makes it easier for lazy folks who can't
> be bothered to read the patch itself.

The explanation fits in one line:
  "Handle multiple instances instead of keeping global state"

I could try adding a paragraph explaining further that this patch will
make the driver handle multiple instances of the device, by keeping its
state per-device instead of in global variables. But that seems
somewhat... redundant.

-- 
David Woodhouse                            Open Source Technology Centre
David.Woodhouse-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org                              Intel Corporation

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[Jean Delvare]

On Sat, 30 Oct 2010 19:47:58 -0400, David Woodhouse wrote:
> On Sun, 2010-10-31 at 00:39 +0100, Ben Dooks wrote:
> > On Sat, Oct 30, 2010 at 07:34:23PM -0400, David Woodhouse wrote:
> > > On Sat, 2010-10-30 at 18:24 +0200, Jean Delvare wrote:
> > > > An explanation why this change is needed would be nice.
> > > 
> > > Um, does it really need explaining? It's really poor form to keep driver
> > > state in global variables rather than per-instance, even if you *don't*
> > > actually have more than one device.

This is actually a good second half for an explanation paragraph.

> > I always like to fill it in, it makes it easier for lazy folks who can't
> > be bothered to read the patch itself.
> 
> The explanation fits in one line:
>   "Handle multiple instances instead of keeping global state"

No, this isn't en explanation. This is a statement of _what_ your patch
does. This is needed but not sufficient. What is additionally requested
from you is an explanation _why_ it does it.

> I could try adding a paragraph explaining further that this patch will
> make the driver handle multiple instances of the device, by keeping its
> state per-device instead of in global variables. But that seems
> somewhat... redundant.

You want to explain that the assumption of the original driver author
that there can be only one supported device with one SMBus interface on
a given system no longer holds true for new devices to be released soon.

Thanks,
-- 
Jean Delvare

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[Jean Delvare]

On Sat, 30 Oct 2010 19:12:07 -0400, David Woodhouse wrote:
> On Sun, 2010-10-31 at 00:00 +0100, Ben Dooks wrote:
> > 
> > > I'd rather stick to (C). Using non-ASCII characters is asking for
> > > trouble, and this doesn't add value.
> > 
> > IIRC, and IANAL, (C) is not sufficient in certain areas (such as the UK)
> > to declare copyright. It needs to be either the word Copyright in full,
> > or the proper 'c' in circle. Both is of coures better. 

"Copyright" is there, so we're all set.

"Copyright (C)" has been used for decades and was never reported to be
insufficient.

> This is the 21st century — we really don't have to stick to ASCII any
> more.

... says the guy who was unable to send a properly formatted patch to me
yesterday. They had no charset info, and "file" says "ISO-8859 mail
text".

Yeah, I know, sent from your phone, blah, whatever, this just confirms
my point that using non-ASCII chars is asking for trouble.

Let me summarize:

* You send patches directly to Linus instead of having them reviewed by
  the people listed in MAINTAINERS.
* You do that on the last day of the merge window, and I've never even
  heard of these patches before.
* Your patches are far from perfect.
* You dare make things even more complex by adding charset issues into
  the mix.

Seriously, if you were not who you are, I'd just give up and ignore
your patches altogether.

-- 
Jean Delvare

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[Jean Delvare]

On Sun, 31 Oct 2010 00:39:30 +0100, Ben Dooks wrote:
> On Sat, Oct 30, 2010 at 07:34:23PM -0400, David Woodhouse wrote:
> > On Sat, 2010-10-30 at 18:24 +0200, Jean Delvare wrote:
> > > An explanation why this change is needed would be nice.
> > 
> > Um, does it really need explaining? It's really poor form to keep driver
> > state in global variables rather than per-instance, even if you *don't*
> > actually have more than one device.
> 
> I always like to fill it in, it makes it easier for lazy folks who can't
> be bothered to read the patch itself.
>  
> > It really isn't trouble. We're well into the 21st century now ??? even
> > akpm can cope with UTF-8 :)
> 
> I'd have to check what the kernel's default charset is...

For completeness... Documentation/email-clients.txt says:

"Email clients should not modify the character set encoding of the text.
Emailed patches should be in ASCII or UTF-8 encoding only.
If you configure your email client to send emails with UTF-8 encoding,
you avoid some possible charset problems."

I read this as: if you use non-ASCII, it has to be UTF-8. Not as: use
non-ASCII each time you can.

I would have enforced the use of ASCII only, but I'm not Linus, and I
need no non-ASCII character to spell my name, so my opinion probably
doesn't matter much as far as the whole kernel tree is concerned. But
it is still certainly valid for the part I maintain.

-- 
Jean Delvare

Re: [PATCH 2/2] i2c-i801: Add PCI idents for Sandy Bridge SMBus controllers

[Jean Delvare]

On Sat, 30 Oct 2010 19:15:50 -0400, David Woodhouse wrote:
> On Sat, 2010-10-30 at 18:36 +0200, Jean Delvare wrote:
> > As a side note, I really don't get the point of using 4 different PCI
> > device IDs for exactly the same device. Intel should really start to
> > worry about their numbering space if they keep attributing IDs when
> > they don't need to. 16 bit is fast to exhaust...
> 
> Don't we keep buying companies that have their own PCI vendor ID? :)
> 
> I certainly agree about the 0x1d7[012] IDs -- those seem fairly
> gratuitous. The main one (0x1d22) lacks slave mode though, so it is
> different from the others. Not that we care right now.
> 
> > > 
> > >     Features supported by this driver:
> > >     Software PEC                     no
> > > @@ -127,6 +131,11 @@
> > >   				 SMBHSTSTS_BUS_ERR | SMBHSTSTS_DEV_ERR | \
> > >   				 SMBHSTSTS_INTR)
> > > 
> > > +#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_PCH	0x1d22
> > > +#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA1	0x1d70
> > > +#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA2	0x1d71
> > > +#define PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA3	0x1d72
> > > +
> > 
> > These should go to pci_ids.h together with all other similar defines.
> 
>  *      Do not add new entries to this file unless the definitions
>  *      are shared between multiple drivers.

I get the idea, but then why don't we move all other IDs back to
i2c-i801.c as well? It seems odd to have some of them in pci_ids.h and
the rest in i2c-i801.c.

Not something for this patch though, I agree.

> > >   struct i801_priv {
> > >   	struct i2c_adapter adapter;
> > >   	unsigned long smba;
> > > @@ -602,6 +611,10 @@ static const struct pci_device_id i801_ids[] = {
> > >   	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH10_5) },
> > >   	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS) },
> > >   	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS) },
> > > +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_PCH) },
> > > +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA1) },
> > > +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA2) },
> > > +	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SANDYBRIDGE_SMBUS_EVA3) },
> > >   	{ 0, }
> > >   };
> > > 
> > 
> > You also have to list the new device in drivers/i2c/busses/Kconfig and
> > Documentation/i2c/busses/i2c-i801.
> 
> Will update.

Thanks,
-- 
Jean Delvare

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[Jean Delvare]

Hi David,

On Sat, 30 Oct 2010 19:34:23 -0400, David Woodhouse wrote:
> On Sat, 2010-10-30 at 18:24 +0200, Jean Delvare wrote:
> > An explanation why this change is needed would be nice.
> 
> Um, does it really need explaining? It's really poor form to keep driver
> state in global variables rather than per-instance, even if you *don't*
> actually have more than one device.

True enough. I've even been thinking of sending a similar patch long
ago. The problem is that it's hard to justify the additional cost of
dynamic memory allocation if there's no technical need for it. And
until Sandy Bridge, there wasn't.

> > > (...)
> > > @@ -429,22 +439,23 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
> > >   	/* Experience has shown that the block buffer can only be used for
> > >   	   SMBus (not I2C) block transactions, even though the datasheet
> > >   	   doesn't mention this limitation. */
> > > -	if ((i801_features & FEATURE_BLOCK_BUFFER)
> > > -	 && command != I2C_SMBUS_I2C_BLOCK_DATA
> > > -	 && i801_set_block_buffer_mode() == 0)
> > > -		result = i801_block_transaction_by_block(data, read_write,
> > > -							 hwpec);
> > > +	if ((priv->features & FEATURE_BLOCK_BUFFER)
> > > +	    && command != I2C_SMBUS_I2C_BLOCK_DATA
> > > +	    && i801_set_block_buffer_mode(priv) == 0)
> > 
> > Gratuitous reindentation of code.
> 
> The two continuation lines? I just fixed them to conform to the normal
> kernel indentation,

Normal according to who? I don't see anything wrong with them as they
were before, and it's used in other places of the driver, so it's not
an accident.

> while I was modifying the lines before and after.
> That's entirely normal practice, and not particularly gratuitous,
> surely?

When you send a patch to the wrong person at the wrong time, if you
want it accepted still, you should make it change as little things as
possible.

> > > @@ -457,81 +468,83 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,
> > >   	int hwpec;
> > >   	int block = 0;
> > >   	int ret, xact = 0;
> > > +	struct i801_priv *priv = (void *)adap;
> > 
> > This is horrible and only works by accident (or misdesign if you
> > prefer). Please don't do this. I'm glad I insisted to review this
> > patch...
> > 
> > We have i2c_set/get_adapdata() for this. If you really care about the
> > extra cost, please use the proper container_of() construct. But I don't
> > think the cost is problematic.
> 
> It wasn't the cost I was thinking of; it was the simplicity. One
> allocation, one failure case, one error path. That's why this method is
> fairly common within the kernel.
> 
> However, I have no particular objection to doing separate allocations,
> even though it's not what I'd normally do. I'll send another version.

You got me wrong apparently. I have no objection to the single
structure allocation, this is indeed fairly common and a good thing to
avoid memory fragmentation. I have a strong objection on random casts
from one structure to another on the undocumented assumption that one
contains the other as its first member.

All you have to do to make me happy is:

	i2c_set_adapdata(adap, priv);

in the probe function and

	priv = i2c_get_adapdata(adap);

in this function (and i801_func).

-- 
Jean Delvare

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[David Woodhouse]

On Sun, 2010-10-31 at 10:19 +0100, Jean Delvare wrote:
> On Sat, 30 Oct 2010 19:47:58 -0400, David Woodhouse wrote:
> > On Sun, 2010-10-31 at 00:39 +0100, Ben Dooks wrote:
> > > On Sat, Oct 30, 2010 at 07:34:23PM -0400, David Woodhouse wrote:
> > > > On Sat, 2010-10-30 at 18:24 +0200, Jean Delvare wrote:
> > > > > An explanation why this change is needed would be nice.
> > > > 
> > > > Um, does it really need explaining? It's really poor form to keep driver
> > > > state in global variables rather than per-instance, even if you *don't*
> > > > actually have more than one device.
> 
> This is actually a good second half for an explanation paragraph.
> 
> > > I always like to fill it in, it makes it easier for lazy folks who can't
> > > be bothered to read the patch itself.
> > 
> > The explanation fits in one line:
> >   "Handle multiple instances instead of keeping global state"
> 
> No, this isn't en explanation. This is a statement of _what_ your patch
> does. This is needed but not sufficient. What is additionally requested
> from you is an explanation _why_ it does it.
> 
> > I could try adding a paragraph explaining further that this patch will
> > make the driver handle multiple instances of the device, by keeping its
> > state per-device instead of in global variables. But that seems
> > somewhat... redundant.
> 
> You want to explain that the assumption of the original driver author
> that there can be only one supported device with one SMBus interface on
> a given system no longer holds true for new devices to be released soon.

Pfft. That was covered by this line in the patch itself:

-/* Note: we assume there can only be one I801, with one SMBus interface */

I cannot imagine a realistic case where any further comment in the
changelog would really be useful -- where a competent person glancing at
the resulting commit would be in *any* doubt as to what was being done
and why. But since it's easier to provide a redundant 'explanation' than
to argue about it, I'll include that in the next version too.

-- 
David Woodhouse                            Open Source Technology Centre
David.Woodhouse-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org                              Intel Corporation

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[David Woodhouse]

On Sun, 2010-10-31 at 11:01 +0100, Jean Delvare wrote:
> "Email clients should not modify the character set encoding of the text.
> Emailed patches should be in ASCII or UTF-8 encoding only.
> If you configure your email client to send emails with UTF-8 encoding,
> you avoid some possible charset problems."
> 
> I read this as: if you use non-ASCII, it has to be UTF-8. Not as: use
> non-ASCII each time you can. 

I read that differently; I read it simply as "Everything is UTF-8".

ASCII is just a legacy subset of UTF-8, and (in my reading of the above)
is mentioned only to avoid confusion.

If someone only happens to be sending ASCII, we don't want to confuse
them by making them think there's some conversion needed to turn that
into UTF-8. So we mention explicitly that ASCII is acceptable, even
though that would be implicit if we mentioned only UTF-8.

-- 
David Woodhouse                            Open Source Technology Centre
David.Woodhouse-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org                              Intel Corporation

Re: [PATCH 1/2] i2c-i801: Handle multiple instances instead of keeping global state

[David Woodhouse]

On Sun, 2010-10-31 at 10:56 +0100, Jean Delvare wrote:
> ... says the guy who was unable to send a properly formatted patch to me
> yesterday. They had no charset info, and "file" says "ISO-8859 mail
> text".
> 
> Yeah, I know, sent from your phone, blah, whatever, this just confirms
> my point that using non-ASCII chars is asking for trouble. 

I don't think we can learn much from the misbehaviour of a mail client
which can't even manage to refrain from corrupting the *whitespace* in
the patches :)

Thanks for pointing that out — I've now fixed both the format=flowed
idiocy and the conversion to legacy charsets, so both should be fixed if
ever I have to send patches out that way again.

-- 
David Woodhouse                            Open Source Technology Centre
David.Woodhouse-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org                              Intel Corporation