[PATCH v4 1/8] i2c: i801: store and restore the SLVCMD register at load and unload
From: Benjamin Tissoires <hidden>
Date: 2016-10-10 16:42:46
Also in:
linux-i2c, lkml
Subsystem:
i2c subsystem, i2c subsystem host drivers, i2c/smbus controller drivers for pc, the rest · Maintainers:
Wolfram Sang, Andi Shyti, Jean Delvare, Linus Torvalds
Also do not override any other configuration in this register. Signed-off-by: Benjamin Tissoires <redacted> --- changes in v4: - add the i801_disable_host_notify function here as this gets the first in the series no changes in v3 new in v2 --- 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 22a0ed4..3a2fdf5 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c@@ -240,6 +240,7 @@ 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;
@@ -952,13 +953,26 @@ 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,
@@ -1647,6 +1661,7 @@ 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);
--
2.7.4