i2c-i801: Clear special mode bits as needed

Clear special mode bits (PEC, block buffer) at driver load time,
you never know in which state the device was left by its last user.

Also make sure that we reset the block buffer mode at the end of every
transaction, not only when PEC was used.

Signed-off-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 6 insertions, 1 deletions

diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index c31699d8df3..0b1b1ae5e22 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -502,7 +502,7 @@ static s32 i801_access(struct i2c_adapter * adap, u16 addr,
         /* 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)
+        if (hwpec || block)
                 outb_p(inb_p(SMBAUXCTL) & ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B),
                        SMBAUXCTL);
 
@@ -625,6 +625,11 @@ static int __devinit i801_probe(struct pci_dev *dev, const struct pci_device_id
         else
                 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);
+
         /* set up the sysfs linkage to our parent device */
         i801_adapter.dev.parent = &dev->dev;