From ae574196ef79bc40afad6bf745dab6c19643e830 Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Wed, 21 Jul 2021 18:11:51 -0400 Subject: [PATCH] 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 6605796bfa6bc20cf6265f1725dd49b3ba4a0d62 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 --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) 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 0a1dd25e567d9..6449999d6bd77 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) -- 2.39.5