i2c: i801: Fix resume bug

commit 66d402e2e9 upstream.

On suspend the original host configuration gets restored. The
resume routine has to undo this, otherwise the SMBus master
may be left in disabled state or in i2c mode.

[JD: Rebased on v5.8, moved the write into i801_setup_hstcfg.]

Signed-off-by: Volker Rümelin <vr_qemu@t-online.de>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Volker Rümelin 2020-09-01 15:22:21 +02:00 committed by Greg Kroah-Hartman
parent 7c96edc6e7
commit b0b68bfe72
1 changed files with 14 additions and 7 deletions

View File

@ -1688,6 +1688,16 @@ static inline int i801_acpi_probe(struct i801_priv *priv) { return 0; }
static inline void i801_acpi_remove(struct i801_priv *priv) { }
#endif
static unsigned char i801_setup_hstcfg(struct i801_priv *priv)
{
unsigned char hstcfg = priv->original_hstcfg;
hstcfg &= ~SMBHSTCFG_I2C_EN; /* SMBus timing */
hstcfg |= SMBHSTCFG_HST_EN;
pci_write_config_byte(priv->pci_dev, SMBHSTCFG, hstcfg);
return hstcfg;
}
static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
unsigned char temp;
@ -1804,14 +1814,10 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
return err;
}
pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &temp);
priv->original_hstcfg = temp;
temp &= ~SMBHSTCFG_I2C_EN; /* SMBus timing */
if (!(temp & SMBHSTCFG_HST_EN)) {
pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &priv->original_hstcfg);
temp = i801_setup_hstcfg(priv);
if (!(priv->original_hstcfg & SMBHSTCFG_HST_EN))
dev_info(&dev->dev, "Enabling SMBus device\n");
temp |= SMBHSTCFG_HST_EN;
}
pci_write_config_byte(priv->pci_dev, SMBHSTCFG, temp);
if (temp & SMBHSTCFG_SMB_SMI_EN) {
dev_dbg(&dev->dev, "SMBus using interrupt SMI#\n");
@ -1937,6 +1943,7 @@ static int i801_resume(struct device *dev)
{
struct i801_priv *priv = dev_get_drvdata(dev);
i801_setup_hstcfg(priv);
i801_enable_host_notify(&priv->adapter);
return 0;