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Only use the firmware brightness levels when both AC and DC values are non-zero Signed-off-by: Edson Juliano Drosdeck --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 4 +++- 1 file changed, 3 insertions(+), 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 5fc5d5608506..f947ce2a8625 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -5380,7 +5380,9 @@ amdgpu_dm_register_backlight_device(struct amdgpu_dm_connector *aconnector) } caps = &dm->backlight_caps[aconnector->bl_idx]; - if (get_brightness_range(caps, &min, &max)) { + if (get_brightness_range(caps, &min, &max) && + caps->ac_level > 0 && + caps->dc_level > 0) { if (power_supply_is_system_supplied() > 0) props.brightness = DIV_ROUND_CLOSEST((max - min) * caps->ac_level, 100); else -- 2.47.3