From: Alex Deucher Date: Wed, 21 Jul 2021 22:11:51 +0000 (-0400) Subject: drm/amdgpu/display: only enable aux backlight control for OLED panels X-Git-Tag: v5.15~303^2~20^2~10 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d0ae0b64fd13db7676307097e72e2480549eeaa5;p=platform%2Fkernel%2Flinux-starfive.git drm/amdgpu/display: only enable aux backlight control for OLED panels We've gotten a number of reports about backlight control not working on panels which indicate that they use aux backlight control. A recent patch: commit 2d73eabe2984a435737498ab39bb1500a9ffe9a9 Author: Camille Cho Date: Thu Jul 8 18:28:37 2021 +0800 drm/amd/display: Only set default brightness for OLED [Why] We used to unconditionally set backlight path as AUX for panels capable of backlight adjustment via DPCD in set default brightness. [How] This should be limited to OLED panel only since we control backlight via PWM path for SDR mode in LCD HDR panel. Reviewed-by: Krunoslav Kovac Acked-by: Rodrigo Siqueira Signed-off-by: Camille Cho Signed-off-by: Alex Deucher Changes some other code to only use aux for backlight control on OLED panels. The commit message seems to indicate that PWM should be used for SDR mode on HDR panels. Do something similar for backlight control in general. This may need to be revisited if and when HDR started to get used. Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1438 Bug: https://bugzilla.kernel.org/show_bug.cgi?id=213715 Reviewed-by: Roman Li Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index 0a1dd25..6449999 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -2429,9 +2429,9 @@ static void update_connector_ext_caps(struct amdgpu_dm_connector *aconnector) max_cll = conn_base->hdr_sink_metadata.hdmi_type1.max_cll; min_cll = conn_base->hdr_sink_metadata.hdmi_type1.min_cll; - if (caps->ext_caps->bits.oled == 1 || + if (caps->ext_caps->bits.oled == 1 /*|| caps->ext_caps->bits.sdr_aux_backlight_control == 1 || - caps->ext_caps->bits.hdr_aux_backlight_control == 1) + caps->ext_caps->bits.hdr_aux_backlight_control == 1*/) caps->aux_support = true; if (amdgpu_backlight == 0)