kernel/linux.git/drivers/acpi/video_detect.c, branch linux-7.1.y

ACPI: video: force native backlight on HP OMEN 16 (8A44)

2026-04-27T20:00:00+00:00

The HP OMEN 16 Gaming Laptop (board name 8A44) has a mux-less hybrid GPU configuration with AMD Rembrandt (Radeon 680M) and NVIDIA GA104 (RTX 3070 Ti). The internal eDP panel is wired to the AMD iGPU. When Nouveau loads without GSP firmware, the ACPI video backlight device (acpi_video0) gets registered alongside the native AMD backlight (amdgpu_bl2). In this state, writes to amdgpu_bl2 update the software brightness value but fail to change the physical panel brightness. Force native backlight to prevent acpi_video0 from registering. Confirmed that booting with acpi_backlight=native resolves the issue. Cc: All applicable Signed-off-by: Shivam Kalra Link: https://patch.msgid.link/20260426-omen-16-backlight-fix-v1-1-62364f268ea6@zohomail.in Signed-off-by: Rafael J. Wysocki

ACPI: video: Move Lenovo Legion S7 15ACH6 quirk to the right section

2026-04-15T14:58:55+00:00

The video_detect_dmi_table[] quirk table has different sections for different types of problems. The Lenovo Legion S7 15ACH6 quirk deals with a non working nvidia_wmi_ec backlight, move it to the section with the other models with this problem. While at it also add a comment with the laptop model name to the quirk. Fixes: f144bc21befd ("ACPI: video: force native for Lenovo 82K8") Signed-off-by: Hans de Goede Link: https://patch.msgid.link/20260413093100.24993-1-johannes.goede@oss.qualcomm.com Signed-off-by: Rafael J. Wysocki

ACPI: video: Add backlight=native quirk for Dell OptiPlex 7770 AIO

2026-04-15T14:56:41+00:00

The Dell OptiPlex 7770 AIO needs the same quirk as the 7760 AIO. The backlight can be controlled with the native controller, intel_backlight, but not with dell_uart_backlight. I dumped the DSDT using acpidump, acpixtract and iasl, and confirmed that it contains the DELL0501 device. When loading the dell_uart_backlight driver with `rmmod dell_uart_backlight`, `modprobe dell_uart_backlight dyndbg`, it reports "Firmware version: GL_Re_V18". Fixes: cd8e468efb4f ("ACPI: video: Add Dell UART backlight controller detection") Cc: All applicable Signed-off-by: Jan Schär Reviewed-by: Hans de Goede Link: https://patch.msgid.link/20260411092606.47925-1-jan@jschaer.ch Signed-off-by: Rafael J. Wysocki

ACPI: video: force native for Lenovo 82K8

2025-08-25T18:00:17+00:00

Lenovo 82K8 has a broken brightness control provided by nvidia_wmi_ec. Add a quirk to prevent using it. Reported-by: Wilson Alvarez Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4512 Tested-by: Wilson Alvarez Signed-off-by: Mario Limonciello (AMD) Link: https://patch.msgid.link/20250820170927.895573-1-superm1@kernel.org Signed-off-by: Rafael J. Wysocki

ACPI: video: force native for Apple MacbookPro11,2 and Air7,2

2024-11-13T11:48:50+00:00

There is a bug in the Macbook Pro 11,2 and Air 7,2 firmware similar to what is described in: commit 7dc918daaf29 ("ACPI: video: force native for Apple MacbookPro9,2") This bug causes their backlights not to come back after resume. Add DMI quirks to select the working native Intel firmware interface such that the backlght comes back on after resume. Signed-off-by: Jonathan Denose Link: https://patch.msgid.link/20241112222516.1.I7fa78e6acbbed56ed5677f5e2dacc098a269d955@changeid [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki

ACPI: video: Add backlight=native quirk for Dell OptiPlex 5480 AIO

2024-10-01T18:51:26+00:00

Dell All In One (AIO) models released after 2017 may use a backlight controller board connected to an UART. In DSDT this uart port will be defined as: Name (_HID, "DELL0501") Name (_CID, EisaId ("PNP0501") The Dell OptiPlex 5480 AIO has an ACPI device for one of its UARTs with the above _HID + _CID. Loading the dell-uart-backlight driver fails with the following errors: [ 18.261353] dell_uart_backlight serial0-0: Timed out waiting for response. [ 18.261356] dell_uart_backlight serial0-0: error -ETIMEDOUT: getting firmware version [ 18.261359] dell_uart_backlight serial0-0: probe with driver dell_uart_backlight failed with error -110 Indicating that there is no backlight controller board attached to the UART, while the GPU's native backlight control method does work. Add a quirk to use the GPU's native backlight control method on this model. Fixes: cd8e468efb4f ("ACPI: video: Add Dell UART backlight controller detection") Cc: All applicable Signed-off-by: Hans de Goede Link: https://patch.msgid.link/20240918153849.37221-1-hdegoede@redhat.com [ rjw: Changelog edit ] Signed-off-by: Rafael J. Wysocki

ACPI: video: Add force_vendor quirk for Panasonic Toughbook CF-18

2024-09-10T18:15:01+00:00

The Panasonic Toughbook CF-18 advertises both native and vendor backlight control interfaces. But only the vendor one actually works. acpi_video_get_backlight_type() will pick the non working native backlight by default, add a quirk to select the working vendor backlight instead. Signed-off-by: Hans de Goede Link: https://patch.msgid.link/20240907124419.21195-1-hdegoede@redhat.com Signed-off-by: Rafael J. Wysocki

ACPI: video: Make Lenovo Yoga Tab 3 X90F DMI match less strict

2024-08-29T10:47:53+00:00

There are 2G and 4G RAM versions of the Lenovo Yoga Tab 3 X90F and it turns out that the 2G version has a DMI product name of "CHERRYVIEW D1 PLATFORM" where as the 4G version has "CHERRYVIEW C0 PLATFORM". The sys-vendor + product-version check are unique enough that the product-name check is not necessary. Drop the product-name check so that the existing DMI match for the 4G RAM version also matches the 2G RAM version. Signed-off-by: Hans de Goede Link: https://patch.msgid.link/20240825132322.6776-1-hdegoede@redhat.com Signed-off-by: Rafael J. Wysocki

ACPI: video: force native for Apple MacbookPro9,2

2024-08-26T17:23:14+00:00

It used to be that the MacbookPro9,2 used its native intel backlight device until the following commit was introduced: commit b1d36e73cc1c ("drm/i915: Don't register backlight when another backlight should be used (v2)") This commit forced this model to use its firmware acpi_video backlight device instead. That worked fine until an additional commit was added: commit 92714006eb4d ("drm/i915/backlight: Do not bump min brightness to max on enable") That commit uncovered a bug in the MacbookPro 9,2's acpi_video backlight firmware; the backlight does not come back up after resume. Add DMI quirk to select the working native intel interface instead so that the backlight successfully comes back up after resume. Fixes: 92714006eb4d ("drm/i915/backlight: Do not bump min brightness to max on enable") Signed-off-by: Esther Shimanovich Reviewed-by: Hans de Goede Link: https://patch.msgid.link/20240806-acpi-video-quirk-v1-1-369d8f7abc59@chromium.org [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki

ACPI: video: Add backlight=native quirk for Dell OptiPlex 7760 AIO

2024-08-19T13:58:52+00:00

Dell All In One (AIO) models released after 2017 may use a backlight controller board connected to an UART. In DSDT this uart port will be defined as: Name (_HID, "DELL0501") Name (_CID, EisaId ("PNP0501") The Dell OptiPlex 7760 AIO has an ACPI device for one if its UARTs with the above _HID + _CID. Loading the dell-uart-backlight driver shows that there actually is a backlight controller board attached to the UART, which reports a firmware version of "G&MX01-V15". But the backlight controller board does not actually control the backlight brightness and the GPU's native backlight control method does work. Add a quirk to use the GPU's native backlight control method on this model. Fixes: 484bae9e4d6a ("platform/x86: Add new Dell UART backlight driver") Closes: https://bugzilla.redhat.com/show_bug.cgi?id=2303936 Cc: All applicable Signed-off-by: Hans de Goede Reviewed-by: Andy Shevchenko Link: https://patch.msgid.link/20240814190159.15650-4-hdegoede@redhat.com Signed-off-by: Rafael J. Wysocki