[PATCH 4.14 15/17] ACPI: video: Force backlight native for Clevo NL5xRU and NL5xNU

Greg Kroah-Hartman
2022-03-25T15:06:55Z

From: Werner Sembach <wse@tuxedocomputers.com>

commit c844d22fe0c0b37dc809adbdde6ceb6462c43acf upstream.

Clevo NL5xRU and NL5xNU/TUXEDO Aura 15 Gen1 and Gen2 have both 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@tuxedocomputers.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/acpi/video_detect.c | 75 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 75 insertions(+)

--- a/drivers/acpi/video_detect.c
+++ b/drivers/acpi/video_detect.c
@@ -356,6 +356,81 @@ static const struct dmi_system_id video_
DMI_MATCH(DMI_BOARD_NAME, "BA51_MV"),
},
},
+ /*
+ * Clevo NL5xRU and NL5xNU/TUXEDO Aura 15 Gen1 and Gen2 have both 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.
+ */
+ {
+ .callback = video_detect_force_native,
+ .ident = "Clevo NL5xRU",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"),
+ DMI_MATCH(DMI_BOARD_NAME, "NL5xRU"),
+ },
+ },
+ {
+ .callback = video_detect_force_native,
+ .ident = "Clevo NL5xRU",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "SchenkerTechnologiesGmbH"),
+ DMI_MATCH(DMI_BOARD_NAME, "NL5xRU"),
+ },
+ },
+ {
+ .callback = video_detect_force_native,
+ .ident = "Clevo NL5xRU",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Notebook"),
+ DMI_MATCH(DMI_BOARD_NAME, "NL5xRU"),
+ },
+ },
+ {
+ .callback = video_detect_force_native,
+ .ident = "Clevo NL5xRU",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"),
+ DMI_MATCH(DMI_BOARD_NAME, "AURA1501"),
+ },
+ },
+ {
+ .callback = video_detect_force_native,
+ .ident = "Clevo NL5xRU",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"),
+ DMI_MATCH(DMI_BOARD_NAME, "EDUBOOK1502"),
+ },
+ },
+ {
+ .callback = video_detect_force_native,
+ .ident = "Clevo NL5xNU",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"),
+ DMI_MATCH(DMI_BOARD_NAME, "NL5xNU"),
+ },
+ },
+ {
+ .callback = video_detect_force_native,
+ .ident = "Clevo NL5xNU",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "SchenkerTechnologiesGmbH"),
+ DMI_MATCH(DMI_BOARD_NAME, "NL5xNU"),
+ },
+ },
+ {
+ .callback = video_detect_force_native,
+ .ident = "Clevo NL5xNU",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Notebook"),
+ DMI_MATCH(DMI_BOARD_NAME, "NL5xNU"),
+ },
+ },

/*
* Desktops which falsely report a backlight and which our heuristics