Turns out Some panels allow only backlight AUX based backlight
by just setting the DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP and
not setting the DP_EDP_BACKLIGHT_AUX_ENABLE_CAP.
If we make DP_EDP_BACKLIGHT_AUX_ENABLE_CAP a necessity for AUX
based DPCD backlight these panels loose the ability to manipulate
backlight via AUX, specially ones with no PWM controller.
Remove this check from function so that panels who do not advertise
DP_EDP_BACKLIGHT_AUX_ENABLE_CAP but advertise
DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP are able to manipulate
backlight again.
Fixes: ed8be780bdbc ("drm/i915/backlight: Fix VESA backlight possible check
condition")
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/work_items/16507
Signed-off-by: Suraj Kandpal <[email protected]>
---
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 7a6c07f6aaeb..b859d5d0613c 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
@@ -619,8 +619,7 @@ check_if_vesa_backlight_possible(struct intel_dp *intel_dp)
* Since we only support Fully AUX Based VESA Backlight interface make
sure
* backlight enable is possible via AUX along with backlight adjustment
*/
- if (!(intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP &&
- intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP))
+ if (!intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP)
return false;
ret = drm_dp_dpcd_read_byte(&intel_dp->aux,
DP_EDP_PWMGEN_BIT_COUNT_CAP_MIN, &bit_min);
--
2.34.1
