From c5b53d128130b39371303a01fbbe1d7d6f519ca5 Mon Sep 17 00:00:00 2001 From: Zhan Liu Date: Thu, 8 Jul 2021 00:51:52 -0400 Subject: [PATCH] drm/amdgpu/display - only update eDP's backlight level when necessary [Why] The original logic is to update eDP's backlight level on every amdgpu dm atomic commit, which causes excessive DMUB write. As a result, when playing game or moving window around, DMUB timeout and system lagging are observed. [How] We only need to update eDP's backlight level when current level doesn't match requested level. Signed-off-by: Zhan Liu Reviewed-by: Alex Deucher Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) 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 f69be12..5cdb0e7 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -9191,7 +9191,7 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state) #if defined(CONFIG_BACKLIGHT_CLASS_DEVICE) || \ defined(CONFIG_BACKLIGHT_CLASS_DEVICE_MODULE) /* restore the backlight level */ - if (dm->backlight_dev) + if (dm->backlight_dev && (amdgpu_dm_backlight_get_level(dm) != dm->brightness[0])) amdgpu_dm_backlight_set_level(dm, dm->brightness[0]); #endif /* -- 2.7.4