diff options
| -rw-r--r-- | drivers/acpi/video.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index e9d4bb60c35c..c9fa4621ed25 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -1539,14 +1539,20 @@ static int acpi_video_bus_put_devices(struct acpi_video_bus *video) /* acpi_video interface */ +/* + * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't + * preform any automatic brightness change on receiving a notification. + */ static int acpi_video_bus_start_devices(struct acpi_video_bus *video) { - return acpi_video_bus_DOS(video, 0, 0); + return acpi_video_bus_DOS(video, 0, + acpi_video_backlight_quirks() ? 1 : 0); } static int acpi_video_bus_stop_devices(struct acpi_video_bus *video) { - return acpi_video_bus_DOS(video, 0, 1); + return acpi_video_bus_DOS(video, 0, + acpi_video_backlight_quirks() ? 0 : 1); } static void acpi_video_bus_notify(struct acpi_device *device, u32 event) |