From 525ba51157ac6e1772b5412eae26b20dd7ef8bda Mon Sep 17 00:00:00 2001 From: Marcos Paulo Medeiros Date: Mon, 27 Jul 2026 10:21:51 -0300 Subject: [PATCH] ACPI: video: force native backlight on Acer Nitro AN515-46 The Acer Nitro AN515-46 is a hybrid graphics laptop whose internal panel is driven by the AMD GPU (Radeon 680M); the discrete NVIDIA GPU only drives external outputs. The firmware nevertheless advertises the NVIDIA WMI EC backlight GUID, so the backlight type resolves to nvidia_wmi_ec. The nvidia-wmi-ec-backlight driver however fails to probe ("EC backlight control failed: AE_NOT_FOUND") and, since the backlight type is still nvidia_wmi_ec, amdgpu skips registering its own backlight device. The result is no backlight device at all, leaving the brightness keys and the desktop brightness slider non-functional. Booting with acpi_backlight=native makes amdgpu register its backlight interface and brightness control works. Add a DMI quirk to use the native backlight on this model by default. Signed-off-by: Marcos Paulo Medeiros Link: https://patch.msgid.link/20260727132151.12792-1-maarcospm1996@gmail.com Signed-off-by: Rafael J. Wysocki --- drivers/acpi/video_detect.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index 5b0dc679e322..07755b856973 100644 --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -919,6 +919,14 @@ static const struct dmi_system_id video_detect_dmi_table[] = { DMI_MATCH(DMI_PRODUCT_NAME, "OMEN by HP Gaming Laptop 16-n0xxx"), }, }, + { + .callback = video_detect_force_native, + /* Acer Nitro AN515-46 */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Acer"), + DMI_MATCH(DMI_PRODUCT_NAME, "Nitro AN515-46"), + }, + }, /* * x86 android tablets which directly control the backlight through