[PATCH 1/2] drm/i915/dpcd_bl: uncheck PWM_PIN_CAP when detect eDP backlight capabilities

From: Aaron Ma
Date: Fri Oct 09 2020 - 04:58:13 EST


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;
}
--
2.25.1