[Intel-gfx] [PATCH v5 5/9] drm/i915: Set backlight mode before enable backlight

[Pandiyan, Dhinakaran]

On Wed, 2017-05-03 at 17:28 -0700, Puthikorn Voravootivat wrote:
> We should set backlight mode register before set register to
> enable the backlight.
> 

Sounds reasonable, although I did not find anything in the spec. that
says we should do this. If you've tested and it works, 
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>




> Signed-off-by: Puthikorn Voravootivat <puthik at chromium.org>
> ---
>  drivers/gpu/drm/i915/intel_dp_aux_backlight.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c
> index e82f7cb9a7af..5ef3ade7c40e 100644
> --- a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c
> +++ b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c
> @@ -103,8 +103,6 @@ static void intel_dp_aux_enable_backlight(struct intel_connector *connector)
>  	uint8_t dpcd_buf = 0;
>  	uint8_t edp_backlight_mode = 0;
>  
> -	set_aux_backlight_enable(intel_dp, true);
> -
>  	if (drm_dp_dpcd_readb(&intel_dp->aux,
>  			DP_EDP_BACKLIGHT_MODE_SET_REGISTER, &dpcd_buf) != 1) {
>  		DRM_DEBUG_KMS("Failed to read DPCD register 0x%x\n",
> @@ -131,6 +129,8 @@ static void intel_dp_aux_enable_backlight(struct intel_connector *connector)
>  	default:
>  		break;
>  	}
> +
> +	set_aux_backlight_enable(intel_dp, true);
>  }
>  
>  static void intel_dp_aux_disable_backlight(struct intel_connector *connector)