From 3120d03cf64d7f9fd71231827af2c1550aa4caa7 Mon Sep 17 00:00:00 2001 From: Jens Reyer Date: Tue, 17 Feb 2015 19:07:29 +0100 Subject: [PATCH] ACPI / video: Disable native backlight on Samsung Series 9 laptops Add video_disable_native_backlight quirk for SAMSUNG 900X3C/900X3D/ 900X3E/900X4C/900X4D laptops. The native intel backlight controls do not work correctly on SAMSUNG Series 9 (900X3C/900X3D/900X3E/900X4C/900X4D) laptops: One machine has an completely dimmed (= black) display after boot at the GDM login screen and brightness controls work only between 0 and 5% (= no effect). Another machine has the same brightness control issues if an external HDMI monitor is or gets connected, although the initial brightness is ok. After login to Gnome both machines always work fine. Tested on both machines. Link: https://bugs.freedesktop.org/show_bug.cgi?id=87286 Link: https://bugs.debian.org/772440 Signed-off-by: Jens Reyer Signed-off-by: Rafael J. Wysocki --- drivers/acpi/video.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index 88a4f99..debd309 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -540,6 +540,15 @@ static struct dmi_system_id video_dmi_table[] __initdata = { DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"), }, }, + { + /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */ + .callback = video_disable_native_backlight, + .ident = "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."), + DMI_MATCH(DMI_PRODUCT_NAME, "900X3C/900X3D/900X3E/900X4C/900X4D"), + }, + }, { /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */ -- 2.7.4