From 9902879dbf2ccd9bacf46b5a61b8aa7ba5ba4ea4 Mon Sep 17 00:00:00 2001
From: Alex Deucher <alexander.deucher@amd.com>
Date: Fri, 30 Jul 2021 16:02:28 +0800
Subject: [PATCH] drm/amdgpu/display: only enable aux backlight control for
OLED panels
BugLink: https://bugs.launchpad.net/bugs/1934557
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 <Camille.Cho@amd.com>
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 <krunoslav.kovac@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Camille Cho <Camille.Cho@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
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 <Roman.Li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit f2ad3accefc63e72e9932e141c21875cc04beec8)
Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Acked-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Chia-Lin Kao (AceLan) <acelan.kao@canonical.com>
---
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 a582091ca3953..c405cb1189447 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2227,9 +2227,9 @@ 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)