This is a note to let you know that I've just added the patch titled
ACPI: video: Add backlight=native DMI quirk for HP EliteBook 8460p
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
acpi-video-add-backlight-native-dmi-quirk-for-hp-eli.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 5bd152b6600bbf13f2e60f46ddb39551f3bfa541
Author: Hans de Goede <hdegoede@xxxxxxxxxx>
Date: Thu Jan 19 17:37:44 2023 +0100
ACPI: video: Add backlight=native DMI quirk for HP EliteBook 8460p
[ Upstream commit 9dcb34234b8235144c96103266317da33321077e ]
The HP EliteBook 8460p predates Windows 8, so it defaults to using
acpi_video# for backlight control.
Starting with the 6.1.y kernels the native radeon_bl0 backlight is hidden
in this case instead of relying on userspace preferring acpi_video# over
native backlight devices.
It turns out that for the acpi_video# interface to work on
the HP EliteBook 8460p, the brightness needs to be set at least once
through the native interface, which now no longer is done breaking
backlight control.
The native interface however always works without problems, so add
a quirk to use native backlight on the EliteBook 8460p to fix this.
Fixes: fb1836c91317 ("ACPI: video: Prefer native over vendor")
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2161428
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c
index c20fc7ddca2f..4719978b8aa3 100644
--- a/drivers/acpi/video_detect.c
+++ b/drivers/acpi/video_detect.c
@@ -608,6 +608,14 @@ static const struct dmi_system_id video_detect_dmi_table[] = {
DMI_MATCH(DMI_PRODUCT_NAME, "UX303UB"),
},
},
+ {
+ .callback = video_detect_force_native,
+ /* HP EliteBook 8460p */
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook 8460p"),
+ },
+ },
{
.callback = video_detect_force_native,
/* HP Pavilion g6-1d80nr / B4U19UA */
