4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dmitry Bazhenov <bazhenov.dn@xxxxxxxxx> commit e7c6a55606b5c46b449d76588968b4d8caae903f upstream. Devices with compatible="pmbus" field have zero initial page count, and pmbus_clear_faults() being called before the page count auto- detection does not actually clear faults because it depends on the page count. Non-cleared faults in its turn may fail the subsequent page count auto-detection. This patch fixes this problem by calling pmbus_clear_fault_page() for currently set page and calling pmbus_clear_faults() after the page count was detected. Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Dmitry Bazhenov <bazhenov.dn@xxxxxxxxx> Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/hwmon/pmbus/pmbus.c | 2 ++ drivers/hwmon/pmbus/pmbus_core.c | 5 ++++- 2 files changed, 6 insertions(+), 1 deletion(-) --- a/drivers/hwmon/pmbus/pmbus.c +++ b/drivers/hwmon/pmbus/pmbus.c @@ -117,6 +117,8 @@ static int pmbus_identify(struct i2c_cli } else { info->pages = 1; } + + pmbus_clear_faults(client); } if (pmbus_check_byte_register(client, 0, PMBUS_VOUT_MODE)) { --- a/drivers/hwmon/pmbus/pmbus_core.c +++ b/drivers/hwmon/pmbus/pmbus_core.c @@ -1759,7 +1759,10 @@ static int pmbus_init_common(struct i2c_ if (ret >= 0 && (ret & PB_CAPABILITY_ERROR_CHECK)) client->flags |= I2C_CLIENT_PEC; - pmbus_clear_faults(client); + if (data->info->pages) + pmbus_clear_faults(client); + else + pmbus_clear_fault_page(client, -1); if (info->identify) { ret = (*info->identify)(client, info);