From 6efcaea77668162e28ad4b18c978a3601384a07b Mon Sep 17 00:00:00 2001 From: Volker Rümelin Date: Tue, 1 Sep 2020 15:22:21 +0200 Subject: i2c: i801: Fix resume bug MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit 66d402e2e9455cf0213c42b97f22a0493372d7cc 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 Signed-off-by: Jean Delvare Signed-off-by: Wolfram Sang Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/i2c/busses/i2c-i801.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index 679c6c41f64b..58fc17e46694 100644 --- a/drivers/i2c/busses/i2c-i801.c +++ b/drivers/i2c/busses/i2c-i801.c @@ -1506,6 +1506,16 @@ 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; @@ -1611,14 +1621,10 @@ 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"); @@ -1745,6 +1751,7 @@ static int i801_resume(struct device *dev) struct pci_dev *pci_dev = to_pci_dev(dev); struct i801_priv *priv = pci_get_drvdata(pci_dev); + i801_setup_hstcfg(priv); i801_enable_host_notify(&priv->adapter); return 0; -- cgit v1.2.3