hwmon: (pmbus/core) clear faults after setting smbalert mask

[ Upstream commit 509c3a362675bc995771df74d545548f98e37621 ]

pmbus_write_smbalert_mask() ignores the errors if the chip can't set
smbalert mask the standard way. It is not necessarily a problem for the irq
support if the chip is otherwise properly setup but it may leave an
uncleared fault behind.

pmbus_core will pick the fault on the next register_check(). The register
check will fails regardless of the actual register support by the chip.

This leads to missing attributes or debugfs entries for chips that should
provide them.

We cannot rely on register_check() as PMBUS_SMBALERT_MASK may be read-only.

Unconditionally clear the page fault after setting PMBUS_SMBALERT_MASK to
avoid the problem.

Suggested-by: Guenter Roeck <linux@roeck-us.net>
Fixes: 221819ca4c36 ("hwmon: (pmbus/core) Add interrupt support")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Message-ID: <20241105-tps25990-v4-5-0e312ac70b62@baylibre.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index e592446b26653e2c5789d9f4d8d78631d99a934c..019c5982ba564b93b395b79527544c65760891d5 100644 (file)
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -3199,7 +3199,17 @@ static int pmbus_regulator_notify(struct pmbus_data *data, int page, int event)
 
 static int pmbus_write_smbalert_mask(struct i2c_client *client, u8 page, u8 reg, u8 val)
 {
-       return _pmbus_write_word_data(client, page, PMBUS_SMBALERT_MASK, reg | (val << 8));
+       int ret;
+
+       ret = _pmbus_write_word_data(client, page, PMBUS_SMBALERT_MASK, reg | (val << 8));
+
+       /*
+        * Clear fault systematically in case writing PMBUS_SMBALERT_MASK
+        * is not supported by the chip.
+        */
+       pmbus_clear_fault_page(client, page);
+
+       return ret;
 }
 
 static irqreturn_t pmbus_fault_handler(int irq, void *pdata)