On Fri, Apr 28, 2023 at 3:24 PM Hans de Goede hdegoede@redhat.com wrote:

Remove the acpi_backlight=video quirk for Lenovo ThinkPad W530.

This was intended to help users of the (unsupported) Nvidia binary driver, but this has been reported to cause backlight control issues for users who have the gfx configured in hybrid (dual-GPU) mode, so drop this.

The Nvidia binary driver should call acpi_video_register_backlight() when necessary and this has been reported to Nvidia.

Until this is fixed Nvidia binary driver users can work around this by passing "acpi_backlight=video" on the kernel commandline (with the latest 6.1.y or newer stable series, kernels < 6.1.y don't need this).

Fixes: a5b2781dcab2 ("ACPI: video: Add acpi_backlight=video quirk for Lenovo ThinkPad W530") Reported-by: Русев Путин rockeraliexpress@gmail.com Link: https://lore.kernel.org/linux-acpi/CAK4BXn0ngZRmzx1bodAF8nmYj0PWdUXzPGHofRrs... Cc: stable@vger.kernel.org Cc: Daniel Dadap ddadap@nvidia.com Signed-off-by: Hans de Goede hdegoede@redhat.com

---

drivers/acpi/video_detect.c | 14 -------------- 1 file changed, 14 deletions(-)

diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index 69ef2d9710c2..bcc25d457581 100644 --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -293,20 +293,6 @@ static const struct dmi_system_id video_detect_dmi_table[] = { }, },

•   /*
  

•    * Older models with nvidia GPU which need acpi_video backlight
  

•    * control and where the old nvidia binary driver series does not
  

•    * call acpi_video_register_backlight().
  

•    */
  

•   {
  

•    .callback = video_detect_force_video,
  

•    /* ThinkPad W530 */
  

•    .matches = {
  

•           DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
  

•           DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad W530"),
  

•           },
  

•   },
  

•   /*
     * These models have a working acpi_video backlight control, and using
     * native backlight causes a regression where backlight does not work
  

--

Applied as 6.4-rc material, thanks!