This is a note to let you know that I've just added the patch titled ACPI: video: Force backlight native for some TongFang devices to the 4.14-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-force-backlight-native-for-some-tongfang-devices.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c752089f7cf5b5800c6ace4cdd1a8351ee78a598 Mon Sep 17 00:00:00 2001 From: Werner Sembach <wse@xxxxxxxxxxxxxxxxxxx> Date: Thu, 7 Jul 2022 20:09:52 +0200 Subject: ACPI: video: Force backlight native for some TongFang devices From: Werner Sembach <wse@xxxxxxxxxxxxxxxxxxx> commit c752089f7cf5b5800c6ace4cdd1a8351ee78a598 upstream. The TongFang PF5PU1G, PF4NU1F, PF5NU1G, and PF5LUXG/TUXEDO BA15 Gen10, Pulse 14/15 Gen1, and Pulse 15 Gen2 have the same problem as the Clevo NL5xRU and NL5xNU/TUXEDO Aura 15 Gen1 and Gen2: They have a working native and video interface. However the default detection mechanism first registers the video interface before unregistering it again and switching to the native interface during boot. This results in a dangling SBIOS request for backlight change for some reason, causing the backlight to switch to ~2% once per boot on the first power cord connect or disconnect event. Setting the native interface explicitly circumvents this buggy behaviour by avoiding the unregistering process. Signed-off-by: Werner Sembach <wse@xxxxxxxxxxxxxxxxxxx> Cc: All applicable <stable@xxxxxxxxxxxxxxx> Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/acpi/video_detect.c | 51 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 50 insertions(+), 1 deletion(-) --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -431,7 +431,56 @@ static const struct dmi_system_id video_ DMI_MATCH(DMI_BOARD_NAME, "NL5xNU"), }, }, - + /* + * The TongFang PF5PU1G, PF4NU1F, PF5NU1G, and PF5LUXG/TUXEDO BA15 Gen10, + * Pulse 14/15 Gen1, and Pulse 15 Gen2 have the same problem as the Clevo + * NL5xRU and NL5xNU/TUXEDO Aura 15 Gen1 and Gen2. See the description + * above. + */ + { + .callback = video_detect_force_native, + .ident = "TongFang PF5PU1G", + .matches = { + DMI_MATCH(DMI_BOARD_NAME, "PF5PU1G"), + }, + }, + { + .callback = video_detect_force_native, + .ident = "TongFang PF4NU1F", + .matches = { + DMI_MATCH(DMI_BOARD_NAME, "PF4NU1F"), + }, + }, + { + .callback = video_detect_force_native, + .ident = "TongFang PF4NU1F", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"), + DMI_MATCH(DMI_BOARD_NAME, "PULSE1401"), + }, + }, + { + .callback = video_detect_force_native, + .ident = "TongFang PF5NU1G", + .matches = { + DMI_MATCH(DMI_BOARD_NAME, "PF5NU1G"), + }, + }, + { + .callback = video_detect_force_native, + .ident = "TongFang PF5NU1G", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"), + DMI_MATCH(DMI_BOARD_NAME, "PULSE1501"), + }, + }, + { + .callback = video_detect_force_native, + .ident = "TongFang PF5LUXG", + .matches = { + DMI_MATCH(DMI_BOARD_NAME, "PF5LUXG"), + }, + }, /* * Desktops which falsely report a backlight and which our heuristics * for this do not catch. Patches currently in stable-queue which might be from wse@xxxxxxxxxxxxxxxxxxx are queue-4.14/acpi-video-shortening-quirk-list-by-identifying-clevo-by-board_name-only.patch queue-4.14/acpi-video-force-backlight-native-for-some-tongfang-devices.patch