From 5a67d2e055897a36acb4e48082986fb4a4eebdd3 Mon Sep 17 00:00:00 2001 From: Roman Li Date: Fri, 21 Aug 2026 12:19:10 -0400 Subject: drm/amd/display: Fix backlight control for luminance-capable OLED [WHY] For some eDP panels VESA aux backlight control is necessary, otherwise they stay black. [HOW] When AUX backlight control is used, select BACKLIGHT_CONTROL_VESA_AUX for panels that advertise panel_luminance_control. Reviewed-by: Hansen Dsouza Signed-off-by: Roman Li Signed-off-by: Alex Hung Tested-by: Dan Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 42f698bd061d76d5f4c84a195e465cfbeec775e4) --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c index e61bbc310f33..b9e90ea449ca 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c @@ -534,8 +534,12 @@ void amdgpu_dm_update_connector_ext_caps(struct amdgpu_dm_connector *aconnector) else if (!IS_ERR_OR_NULL(panel_backlight_quirk) && panel_backlight_quirk->force_pwm) caps->aux_support = false; - if (caps->aux_support) - aconnector->dc_link->backlight_control_type = BACKLIGHT_CONTROL_AMD_AUX; + if (caps->aux_support) { + if (aconnector->dc_link->dpcd_caps.panel_luminance_control) + aconnector->dc_link->backlight_control_type = BACKLIGHT_CONTROL_VESA_AUX; + else + aconnector->dc_link->backlight_control_type = BACKLIGHT_CONTROL_AMD_AUX; + } luminance_range = &conn_base->display_info.luminance_range; -- cgit v1.2.3