RE: [PATCH 6/7] drm/i915/backlight: Setup nits based luminance via VESA

["Murthy, Arun R" <arun.r.murthy@xxxxxxxxx>]

> Modify backlight setup function for VESA interface to take into account the nits
> based luminance.
> 
> --v2
> -Prefer using luminance over nits [Jani]
> 
> Signed-off-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx>
> Tested-by: Ben Kao <ben.kao@xxxxxxxxx>
> ---
Reviewed-by: Arun R Murthy <arun.r.murthy@xxxxxxxxx>

Thanks and Regards,
Arun R Murthy
--------------------

>  .../drm/i915/display/intel_dp_aux_backlight.c | 99 +++++++++++--------
>  1 file changed, 59 insertions(+), 40 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> index a9facfacac95..38e2b8cc591c 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> @@ -560,56 +560,75 @@ static void
> intel_dp_aux_vesa_disable_backlight(const struct drm_connector_state  static
> int intel_dp_aux_vesa_setup_backlight(struct intel_connector *connector,
> enum pipe pipe)  {
>  	struct intel_display *display = to_intel_display(connector);
> +	struct drm_luminance_range_info *luminance_range =
> +		&connector->base.display_info.luminance_range;
>  	struct intel_dp *intel_dp = intel_attached_dp(connector);
>  	struct intel_panel *panel = &connector->panel;
>  	u16 current_level;
>  	u8 current_mode;
>  	int ret;
> 
> -	ret = drm_edp_backlight_init(&intel_dp->aux, &panel-
> >backlight.edp.vesa.info,
> -				     panel->vbt.backlight.pwm_freq_hz,
> intel_dp->edp_dpcd,
> -				     &current_level, &current_mode);
> -	if (ret < 0)
> -		return ret;
> -
> -	drm_dbg_kms(display->drm,
> -		    "[CONNECTOR:%d:%s] AUX VESA backlight enable is
> controlled through %s\n",
> -		    connector->base.base.id, connector->base.name,
> -		    dpcd_vs_pwm_str(panel-
> >backlight.edp.vesa.info.aux_enable));
> -	drm_dbg_kms(display->drm,
> -		    "[CONNECTOR:%d:%s] AUX VESA backlight level is controlled
> through %s\n",
> -		    connector->base.base.id, connector->base.name,
> -		    dpcd_vs_pwm_str(panel->backlight.edp.vesa.info.aux_set));
> -
> -	if (!panel->backlight.edp.vesa.info.aux_set || !panel-
> >backlight.edp.vesa.info.aux_enable) {
> -		ret = panel->backlight.pwm_funcs->setup(connector, pipe);
> -		if (ret < 0) {
> -			drm_err(display->drm,
> -				"[CONNECTOR:%d:%s] Failed to setup PWM
> backlight controls for eDP backlight: %d\n",
> -				connector->base.base.id, connector-
> >base.name, ret);
> -			return ret;
> -		}
> -	}
> -
> -	if (panel->backlight.edp.vesa.info.aux_set) {
> -		panel->backlight.max = panel->backlight.edp.vesa.info.max;
> -		panel->backlight.min = 0;
> -		if (current_mode ==
> DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) {
> -			panel->backlight.level = current_level;
> -			panel->backlight.enabled = panel->backlight.level != 0;
> +	if (panel->backlight.edp.vesa.luminance_control_support) {
> +		if (luminance_range->max_luminance) {
> +			panel->backlight.max = luminance_range-
> >max_luminance;
> +			panel->backlight.min = luminance_range-
> >min_luminance;
>  		} else {
> -			panel->backlight.level = panel->backlight.max;
> -			panel->backlight.enabled = false;
> +			panel->backlight.max = 512;
> +			panel->backlight.min = 0;
>  		}
> +		panel->backlight.level =
> intel_dp_aux_vesa_get_backlight(connector, 0);
> +		panel->backlight.enabled = panel->backlight.level != 0;
> +		drm_dbg_kms(display->drm,
> +			    "[CONNECTOR:%d:%s] AUX VESA Nits backlight level
> is controlled through DPCD\n",
> +			    connector->base.base.id, connector->base.name);
>  	} else {
> -		panel->backlight.max = panel->backlight.pwm_level_max;
> -		panel->backlight.min = panel->backlight.pwm_level_min;
> -		if (current_mode ==
> DP_EDP_BACKLIGHT_CONTROL_MODE_PWM) {
> -			panel->backlight.level = panel->backlight.pwm_funcs-
> >get(connector, pipe);
> -			panel->backlight.enabled = panel-
> >backlight.pwm_enabled;
> +		ret = drm_edp_backlight_init(&intel_dp->aux, &panel-
> >backlight.edp.vesa.info,
> +					     panel->vbt.backlight.pwm_freq_hz,
> intel_dp->edp_dpcd,
> +					     &current_level, &current_mode);
> +		if (ret < 0)
> +			return ret;
> +
> +		drm_dbg_kms(display->drm,
> +			    "[CONNECTOR:%d:%s] AUX VESA backlight enable is
> controlled through %s\n",
> +			    connector->base.base.id, connector->base.name,
> +			    dpcd_vs_pwm_str(panel-
> >backlight.edp.vesa.info.aux_enable));
> +		drm_dbg_kms(display->drm,
> +			    "[CONNECTOR:%d:%s] AUX VESA backlight level is
> controlled through %s\n",
> +			    connector->base.base.id, connector->base.name,
> +			    dpcd_vs_pwm_str(panel-
> >backlight.edp.vesa.info.aux_set));
> +
> +		if (!panel->backlight.edp.vesa.info.aux_set ||
> +		    !panel->backlight.edp.vesa.info.aux_enable) {
> +			ret = panel->backlight.pwm_funcs->setup(connector,
> pipe);
> +			if (ret < 0) {
> +				drm_err(display->drm,
> +					"[CONNECTOR:%d:%s] Failed to setup
> PWM backlight controls for eDP backlight: %d\n",
> +					connector->base.base.id, connector-
> >base.name, ret);
> +				return ret;
> +			}
> +		}
> +
> +		if (panel->backlight.edp.vesa.info.aux_set) {
> +			panel->backlight.max = panel-
> >backlight.edp.vesa.info.max;
> +			panel->backlight.min = 0;
> +			if (current_mode ==
> DP_EDP_BACKLIGHT_CONTROL_MODE_DPCD) {
> +				panel->backlight.level = current_level;
> +				panel->backlight.enabled = panel-
> >backlight.level != 0;
> +			} else {
> +				panel->backlight.level = panel->backlight.max;
> +				panel->backlight.enabled = false;
> +			}
>  		} else {
> -			panel->backlight.level = panel->backlight.max;
> -			panel->backlight.enabled = false;
> +			panel->backlight.max = panel-
> >backlight.pwm_level_max;
> +			panel->backlight.min = panel-
> >backlight.pwm_level_min;
> +			if (current_mode ==
> DP_EDP_BACKLIGHT_CONTROL_MODE_PWM) {
> +				panel->backlight.level =
> +					panel->backlight.pwm_funcs-
> >get(connector, pipe);
> +				panel->backlight.enabled = panel-
> >backlight.pwm_enabled;
> +			} else {
> +				panel->backlight.level = panel->backlight.max;
> +				panel->backlight.enabled = false;
> +			}
>  		}
>  	}
> 
> --
> 2.34.1