hwmon: (mlxreg-fan) Return zero speed for broken fan

[ Upstream commit a1ffd3c462 ]

Currently for broken fan driver returns value calculated based on error
code (0xFF) in related fan speed register.
Thus, for such fan user gets fan{n}_fault to 1 and fan{n}_input with
misleading value.

Add check for fan fault prior return speed value and return zero if
fault is detected.

Fixes: 65afb4c8e7 ("hwmon: (mlxreg-fan) Add support for Mellanox FAN driver")
Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Link: https://lore.kernel.org/r/20230212145730.24247-1-vadimp@nvidia.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Vadim Pasternak 2023-02-12 16:57:30 +02:00 committed by Greg Kroah-Hartman
parent 5281816466
commit 75eef8cb9d

View File

@ -151,6 +151,12 @@ mlxreg_fan_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
if (err)
return err;
if (MLXREG_FAN_GET_FAULT(regval, tacho->mask)) {
/* FAN is broken - return zero for FAN speed. */
*val = 0;
return 0;
}
*val = MLXREG_FAN_GET_RPM(regval, fan->divider,
fan->samples);
break;