[PATCH 4.18 011/350] hwmon: (pmbus) Fix page count auto-detection.

Greg Kroah-Hartman
2018-11-11T23:41:13Z

From: Dmitry Bazhenov <bazhenov.dn@gmail.com>

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@vger.kernel.org
Signed-off-by: Dmitry Bazhenov <bazhenov.dn@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
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
@@ -118,6 +118,8 @@ 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
@@ -2015,7 +2015,10 @@ 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);