Re: [PATCH 07/13] drm/dp: Change argument type for drm_edp_backlight_set_level

[Jani Nikula <jani.nikula@linux.intel.com>]

On Fri, 11 Apr 2025, Suraj Kandpal <suraj.kandpal@intel.com> wrote:
> Use u32 for level variable as one may need to pass value for
> DP_EDP_PANEL_TARGET_LUMINANCE_VALUE.
>
> Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
> ---
>  drivers/gpu/drm/display/drm_dp_helper.c | 6 +++---
>  include/drm/display/drm_dp_helper.h     | 2 +-
>  2 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c
> index bb1242a1bf6b..895ed4a22fc3 100644
> --- a/drivers/gpu/drm/display/drm_dp_helper.c
> +++ b/drivers/gpu/drm/display/drm_dp_helper.c
> @@ -3933,7 +3933,7 @@ EXPORT_SYMBOL(drm_dp_pcon_convert_rgb_to_ycbcr);
>   * Returns: %0 on success, negative error code on failure
>   */
>  int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl,
> -				u16 level)
> +				u32 level)
>  {
>  	int ret;
>  	u8 buf[2] = { 0 };
> @@ -4047,7 +4047,7 @@ int drm_edp_backlight_enable(struct drm_dp_aux *aux, const struct drm_edp_backli
>  		return ret < 0 ? ret : -EIO;
>  	}
>  
> -	ret = drm_edp_backlight_set_level(aux, bl, level);
> +	ret = drm_edp_backlight_set_level(aux, bl, (u32)level);

What difference do you think the cast makes?

>  	if (ret < 0)
>  		return ret;
>  	ret = drm_edp_backlight_set_enable(aux, bl, true);
> @@ -4327,7 +4327,7 @@ static int dp_aux_backlight_update_status(struct backlight_device *bd)
>  			bl->enabled = true;
>  			return 0;
>  		}
> -		ret = drm_edp_backlight_set_level(bl->aux, &bl->info, brightness);
> +		ret = drm_edp_backlight_set_level(bl->aux, &bl->info, (u32)brightness);

Ditto.

>  	} else {
>  		if (bl->enabled) {
>  			drm_edp_backlight_disable(bl->aux, &bl->info);
> diff --git a/include/drm/display/drm_dp_helper.h b/include/drm/display/drm_dp_helper.h
> index 62be80417ded..6bce0176efd3 100644
> --- a/include/drm/display/drm_dp_helper.h
> +++ b/include/drm/display/drm_dp_helper.h
> @@ -853,7 +853,7 @@ drm_edp_backlight_init(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl
>  		       u16 driver_pwm_freq_hz, const u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE],
>  		       u32 *current_level, u8 *current_mode, bool need_luminance);
>  int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl,
> -				u16 level);
> +				u32 level);
>  int drm_edp_backlight_enable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl,
>  			     u16 level);
>  int drm_edp_backlight_disable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl);

-- 
Jani Nikula, Intel