From 22e94bd6779e1140350c0792e85c79552ec43673 Mon Sep 17 00:00:00 2001 From: Benjamin Tissoires Date: Thu, 13 Oct 2016 14:10:35 +0200 Subject: [PATCH] i2c: i801: store and restore the SLVCMD register at load and unload Also do not override any other configuration in this register. Signed-off-by: Benjamin Tissoires Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-i801.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index eb3627f35d12..750c4753e2bc 100644 --- a/drivers/i2c/busses/i2c-i801.c +++ b/drivers/i2c/busses/i2c-i801.c @@ -243,6 +243,7 @@ struct i801_priv { struct i2c_adapter adapter; unsigned long smba; unsigned char original_hstcfg; + unsigned char original_slvcmd; struct pci_dev *pci_dev; unsigned int features; @@ -962,13 +963,26 @@ static int i801_enable_host_notify(struct i2c_adapter *adapter) if (!priv->host_notify) return -ENOMEM; - outb_p(SMBSLVCMD_HST_NTFY_INTREN, SMBSLVCMD(priv)); + priv->original_slvcmd = inb_p(SMBSLVCMD(priv)); + + if (!(SMBSLVCMD_HST_NTFY_INTREN & priv->original_slvcmd)) + outb_p(SMBSLVCMD_HST_NTFY_INTREN | priv->original_slvcmd, + SMBSLVCMD(priv)); + /* clear Host Notify bit to allow a new notification */ outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv)); return 0; } +static void i801_disable_host_notify(struct i801_priv *priv) +{ + if (!(priv->features & FEATURE_HOST_NOTIFY)) + return; + + outb_p(priv->original_slvcmd, SMBSLVCMD(priv)); +} + static const struct i2c_algorithm smbus_algorithm = { .smbus_xfer = i801_access, .functionality = i801_func, @@ -1663,6 +1677,7 @@ static void i801_remove(struct pci_dev *dev) pm_runtime_forbid(&dev->dev); pm_runtime_get_noresume(&dev->dev); + i801_disable_host_notify(priv); i801_del_mux(priv); i2c_del_adapter(&priv->adapter); i801_acpi_remove(priv); -- 2.45.2