hwmon: (pwm-fan) set usage_power on PWM state

PWM fans are controlled solely by the duty cycle of the PWM signal, they
do not care about the exact timing. Thus set usage_power to true to
allow less flexible hardware to work as a PWM source for fan control.

Signed-off-by: Lorenz Brun <lorenz@brun.one>
Link: https://lore.kernel.org/r/20230309011009.2109696-1-lorenz@brun.one
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
index 57928d2..6e4516c 100644 (file)
--- a/drivers/hwmon/pwm-fan.c
+++ b/drivers/hwmon/pwm-fan.c
@@ -508,6 +508,14 @@ static int pwm_fan_probe(struct platform_device *pdev)
        pwm_init_state(ctx->pwm, &ctx->pwm_state);
 
        /*
+        * PWM fans are controlled solely by the duty cycle of the PWM signal,
+        * they do not care about the exact timing. Thus set usage_power to true
+        * to allow less flexible hardware to work as a PWM source for fan
+        * control.
+        */
+       ctx->pwm_state.usage_power = true;
+
+       /*
         * set_pwm assumes that MAX_PWM * (period - 1) fits into an unsigned
         * long. Check this here to prevent the fan running at a too low
         * frequency.