The patch below does not apply to the 5.8-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From ec11fe3705a7d434ec3493bdaddb9b6367e7366a Mon Sep 17 00:00:00 2001
From: hersen wu hersenxs.wu@amd.com Date: Mon, 22 Jun 2020 13:29:16 -0400 Subject: [PATCH] drm/amd/display: OLED panel backlight adjust not work with external display connected
[Why] amdgpu_dm->backlight_caps is for single eDP only. the caps are upddated for very connector. Real eDP caps will be overwritten by other external display. For OLED panel, caps->aux_support is set to 1 for OLED pnael. after external connected, caps+.aux_support is set to 0. This causes OLED backlight adjustment not work.
[How] within update_conector_ext_caps, backlight caps will be updated only for eDP connector.
Cc: stable@vger.kernel.org Signed-off-by: hersen wu hersenxs.wu@amd.com Reviewed-by: Nicholas Kazlauskas Nicholas.Kazlauskas@amd.com Acked-by: Rodrigo Siqueira Rodrigo.Siqueira@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com
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 6f937e25a62c..9c283531e1a2 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -2028,6 +2028,7 @@ static void update_connector_ext_caps(struct amdgpu_dm_connector *aconnector) struct amdgpu_display_manager *dm; struct drm_connector *conn_base; struct amdgpu_device *adev; + struct dc_link *link = NULL; static const u8 pre_computed_values[] = { 50, 51, 52, 53, 55, 56, 57, 58, 59, 61, 62, 63, 65, 66, 68, 69, 71, 72, 74, 75, 77, 79, 81, 82, 84, 86, 88, 90, 92, 94, 96, 98}; @@ -2035,6 +2036,10 @@ static void update_connector_ext_caps(struct amdgpu_dm_connector *aconnector) if (!aconnector || !aconnector->dc_link) return;
+ link = aconnector->dc_link; + if (link->connector_signal != SIGNAL_TYPE_EDP) + return; + conn_base = &aconnector->base; adev = conn_base->dev->dev_private; dm = &adev->dm;