[PATCH] drm/radeon: use 0-255 rather than 0-100 for pwm fan range

Christian König deathsimple at vodafone.de
Thu Feb 5 01:49:37 PST 2015


Am 04.02.2015 um 23:27 schrieb Alex Deucher:
> 0-255 seems to be the preferred range for the pwm interface.
>
> Signed-off-by: Alex Deucher <alexander.deucher at amd.com>

Yeah, using 100 on a 8bit pwm timer sounds rather obviously wrong.

Patch is Reviewed-by: Christian König <christian.koenig at amd.com>

> ---
>   drivers/gpu/drm/radeon/radeon_pm.c | 8 ++++++--
>   1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/radeon/radeon_pm.c b/drivers/gpu/drm/radeon/radeon_pm.c
> index 91e1bd2..9f758d3 100644
> --- a/drivers/gpu/drm/radeon/radeon_pm.c
> +++ b/drivers/gpu/drm/radeon/radeon_pm.c
> @@ -585,7 +585,7 @@ static ssize_t radeon_hwmon_set_pwm1_enable(struct device *dev,
>   	if (err)
>   		return err;
>   
> -	switch(value) {
> +	switch (value) {
>   	case 1: /* manual, percent-based */
>   		rdev->asic->dpm.fan_ctrl_set_mode(rdev, FDO_PWM_MODE_STATIC);
>   		break;
> @@ -608,7 +608,7 @@ static ssize_t radeon_hwmon_get_pwm1_max(struct device *dev,
>   					 struct device_attribute *attr,
>   					 char *buf)
>   {
> -	return sprintf(buf, "%i\n", 100); /* pwm uses percent-based fan-control */
> +	return sprintf(buf, "%i\n", 255);
>   }
>   
>   static ssize_t radeon_hwmon_set_pwm1(struct device *dev,
> @@ -623,6 +623,8 @@ static ssize_t radeon_hwmon_set_pwm1(struct device *dev,
>   	if (err)
>   		return err;
>   
> +	value = (value * 100) / 255;
> +
>   	err = rdev->asic->dpm.set_fan_speed_percent(rdev, value);
>   	if (err)
>   		return err;
> @@ -642,6 +644,8 @@ static ssize_t radeon_hwmon_get_pwm1(struct device *dev,
>   	if (err)
>   		return err;
>   
> +	speed = (speed * 255) / 100;
> +
>   	return sprintf(buf, "%i\n", speed);
>   }
>   



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