X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fi2c%2Fbusses%2Fi2c-piix4.c;h=d9c7c00e71f9df6df1d2b655859918f9b9fd5398;hb=9464c7cf61b9433057924c36e6e02f303a00e768;hp=8f2f65b793b9a355e5f8b0022cd42711e0755644;hpb=41689045f6a3cbe0550e1d34e9cc20d2e8c432ba;p=linux-2.6.git

diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index 8f2f65b79..d9c7c00e7 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -102,6 +102,13 @@ MODULE_PARM_DESC(force_addr,
 		 "Forcibly enable the PIIX4 at the given address. "
 		 "EXTREMELY DANGEROUS!");
 
+/* If fix_hstcfg is set to anything different from 0, we reset one of the
+   registers to be a valid value. */
+static int fix_hstcfg;
+module_param (fix_hstcfg, int, 0);
+MODULE_PARM_DESC(fix_hstcfg,
+		"Fix config register. Needed on some boards (Force CPCI735).");
+
 static int piix4_transaction(void);
 
 static unsigned short piix4_smba;
@@ -130,7 +137,7 @@ static int __devinit piix4_setup(struct pci_dev *PIIX4_dev,
 	/* Don't access SMBus on IBM systems which get corrupted eeproms */
 	if (dmi_check_system(piix4_dmi_table) &&
 			PIIX4_dev->vendor == PCI_VENDOR_ID_INTEL) {
-		dev_err(&PIIX4_dev->dev, "IBM system detected; this module "
+		dev_err(&PIIX4_dev->dev, "IBM Laptop detected; this module "
 			"may corrupt your serial eeprom! Refusing to load "
 			"module!\n");
 		return -EPERM;
@@ -159,6 +166,22 @@ static int __devinit piix4_setup(struct pci_dev *PIIX4_dev,
 
 	pci_read_config_byte(PIIX4_dev, SMBHSTCFG, &temp);
 
+	/* Some BIOS will set up the chipset incorrectly and leave a register
+	   in an undefined state (causing I2C to act very strangely). */
+	if (temp & 0x02) {
+		if (fix_hstcfg) {
+			dev_info(&PIIX4_dev->dev, "Working around buggy BIOS "
+					"(I2C)\n");
+			temp &= 0xfd;
+			pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp);
+		} else {
+			dev_info(&PIIX4_dev->dev, "Unusual config register "
+					"value\n");
+			dev_info(&PIIX4_dev->dev, "Try using fix_hstcfg=1 if "
+					"you experience problems\n");
+		}
+	}
+ 
 	/* If force_addr is set, we program the new address here. Just to make
 	   sure, we disable the PIIX4 first. */
 	if (force_addr) {
@@ -191,7 +214,7 @@ static int __devinit piix4_setup(struct pci_dev *PIIX4_dev,
 		}
 	}
 
-	if (((temp & 0x0E) == 8) || ((temp & 0x0E) == 2))
+	if ((temp & 0x0E) == 8)
 		dev_dbg(&PIIX4_dev->dev, "Using Interrupt 9 for SMBus.\n");
 	else if ((temp & 0x0E) == 0)
 		dev_dbg(&PIIX4_dev->dev, "Using Interrupt SMI# for SMBus.\n");
@@ -390,12 +413,6 @@ static struct i2c_adapter piix4_adapter = {
 static struct pci_device_id piix4_ids[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3),
 	  .driver_data = 3 },
-	{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP200_SMBUS),
-	  .driver_data = 0 },
-	{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP300_SMBUS),
-	  .driver_data = 0 },
-	{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP400_SMBUS),
-	  .driver_data = 0 },
 	{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_OSB4),
 	  .driver_data = 0 },
 	{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_CSB5),