Hi Alex, thank you for your response. On 15.11.2021 10:43, Alex Deucher wrote: > [...] > > That patch adds support for systems with multiple backlights. Do you > have multiple backlight devices now? If so, does the other one work? No, there is still only one backlight device -- amdgpu_bl0. > > Can you also try this patch? > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c > b/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c > index 4811b0faafd9..67163c9d49e6 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c > @@ -854,8 +854,8 @@ int amdgpu_acpi_init(struct amdgpu_device *adev) > if (amdgpu_device_has_dc_support(adev)) { > #if defined(CONFIG_DRM_AMD_DC) > struct amdgpu_display_manager *dm = &adev->dm; > - if (dm->backlight_dev[0]) > - atif->bd = dm->backlight_dev[0]; > + if (dm->backlight_dev[1]) > + atif->bd = dm->backlight_dev[1]; > #endif > } else { > struct drm_encoder *tmp; > There is no difference in behaviour after applying the patch. Samuel > > Alex > > > > > Regards, > > Samuel Čavoj > > > > [0]: https://www.reddit.com/r/AMDLaptops/comments/qst0fm/after_updating_to_linux_515_my_brightness/