From: Mario Limonciello mario.limonciello@amd.com
[ Upstream commit c573e240609ff781a0246c0c8c8351abd0475287 ]
On desktop APUs amdgpu doesn't create a native backlight device as no eDP panels are found. However if the BIOS has reported backlight control methods in the ACPI tables then an acpi_video0 backlight device will be made 8 seconds after boot.
This has manifested in a power slider on a number of desktop APUs ranging from Ryzen 5000 through Ryzen 7000 on various motherboard manufacturers. To avoid this, report to the acpi video detection that the system does not have any panel connected in the native driver.
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1783786 Reported-by: Hans de Goede hdegoede@redhat.com Signed-off-by: Mario Limonciello mario.limonciello@amd.com Reviewed-by: Hans de Goede hdegoede@redhat.com Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 4 ++++ 1 file changed, 4 insertions(+)
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 c2c26fbea512..6f1cc5ce4c7a 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -4372,6 +4372,10 @@ static int amdgpu_dm_initialize_drm_device(struct amdgpu_device *adev) amdgpu_set_panel_orientation(&aconnector->base); }
+ /* If we didn't find a panel, notify the acpi video detection */ + if (dm->adev->flags & AMD_IS_APU && dm->num_of_edps == 0) + acpi_video_report_nolcd(); + /* Software is initialized. Now we can register interrupt handlers. */ switch (adev->asic_type) { #if defined(CONFIG_DRM_AMD_DC_SI)