Commit a1ffd3c4 authored by Vadim Pasternak's avatar Vadim Pasternak Committed by Guenter Roeck
Browse files

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



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: 65afb4c8 ("hwmon: (mlxreg-fan) Add support for Mellanox FAN driver")
Signed-off-by: default avatarVadim Pasternak <vadimp@nvidia.com>
Link: https://lore.kernel.org/r/20230212145730.24247-1-vadimp@nvidia.com


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 102be2c2

drivers/hwmon/mlxreg-fan.c

+6 −0
Original line number Diff line number Diff line
@@ -155,6 +155,12 @@ 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;