[PATCH 4.9 021/101] ACPI: video: Force backlight native for some TongFang devices

[Greg Kroah-Hartman]

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
@@ -210,7 +210,56 @@ 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"),
+		},
+	},
 	/*
 	 * These models have a working acpi_video backlight control, and using
 	 * native backlight causes a regression where backlight does not work