(Cc: drm-misc/intel maintainers) Re: [PATCH 1/2] drm/i915/dpcd_bl: uncheck PWM_PIN_CAP when detect eDP backlight capabilities

From: Lyude Paul
Date: Fri Oct 09 2020 - 13:27:31 EST


For the whole series:

For the whole series:

Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>

I'm going to add a Cc for stable so that it can be backported, and I'll push it
to drm-intel-next-queued once I get the OK from drm-misc/i915 folks

On Fri, 2020-10-09 at 16:57 +0800, Aaron Ma wrote:
> BOE panel with ID 2270 claims both PWM_PIN_CAP and AUX_SET_CAP backlight
> control bits, but default chip backlight failed to control brightness.
>
> Check AUX_SET_CAP and proceed to check quirks or VBT backlight type.
> DPCD can control the brightness of this pannel.
>
> Signed-off-by: Aaron Ma <aaron.ma@xxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c | 3 +--
> 1 file changed, 1 insertion(+), 2 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 acbd7eb66cbe..308b14159b7c 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> @@ -334,8 +334,7 @@ intel_dp_aux_display_control_capable(struct
> intel_connector *connector)
> * the panel can support backlight control over the aux channel
> */
> if (intel_dp->edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP &&
> - (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP) &&
> - !(intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_PWM_PIN_CAP))
> {
> + (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP)) {
> drm_dbg_kms(&i915->drm, "AUX Backlight Control Supported!\n");
> return true;
> }
--
Sincerely,
Lyude Paul (she/her)
Software Engineer at Red Hat