i2c: i801: Restore configuration at shutdown
On some systems, the BIOS expects certain SMBus register values to
match the hardware defaults. Restore these configuration registers at
shutdown time to avoid confusing the BIOS. This avoids hard-locking
such systems upon reboot.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jason Andryuk <jandryuk@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@vger.kernel.org
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 17aa20a..e0d59e9 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -1701,6 +1701,15 @@
*/
}
+static void i801_shutdown(struct pci_dev *dev)
+{
+ struct i801_priv *priv = pci_get_drvdata(dev);
+
+ /* Restore config registers to avoid hard hang on some systems */
+ i801_disable_host_notify(priv);
+ pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
+}
+
#ifdef CONFIG_PM
static int i801_suspend(struct device *dev)
{
@@ -1730,6 +1739,7 @@
.id_table = i801_ids,
.probe = i801_probe,
.remove = i801_remove,
+ .shutdown = i801_shutdown,
.driver = {
.pm = &i801_pm_ops,
},