[PATCH] hwmon: (pmbus) Fix page count auto-detection.

From: Dmitry Bazhenov
Date: Mon Oct 15 2018 - 05:21:42 EST


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.

Signed-off-by: Dmitry Bazhenov <bazhenov.dn@xxxxxxxxx>
---
drivers/hwmon/pmbus/pmbus.c | 2 ++
drivers/hwmon/pmbus/pmbus_core.c | 5 ++++-
2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/hwmon/pmbus/pmbus.c b/drivers/hwmon/pmbus/pmbus.c
index 7718e58dbda5..7688dab32f6e 100644
--- a/drivers/hwmon/pmbus/pmbus.c
+++ b/drivers/hwmon/pmbus/pmbus.c
@@ -118,6 +118,8 @@ static int pmbus_identify(struct i2c_client *client,
} else {
info->pages = 1;
}
+
+ pmbus_clear_faults(client);
}

if (pmbus_check_byte_register(client, 0, PMBUS_VOUT_MODE)) {
diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 82c3754e21e3..2e2b5851139c 100644
--- 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_client *client, struct pmbus_data *data,
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);
--
2.17.1