On Monday, June 17, 2013 09:01:10 AM Aaron Lu wrote: > Starting from win8, MS backlight control driver will set bit 2 of the > parameter of control method _DOS, to inform firmware it should not > perform any automatic brightness changes. This mostly affects hotkey > notification deliver - if we do not set this bit, on hotkey press, > firmware may choose to adjust brightness level instead of sending out > notification and doing nothing. > > So this patch sets bit 2 when calling _DOS so that GUIs can show the > notification window on hotkey press. > > The MS document on win8 backlight control is here: > http://msdn.microsoft.com/en-US/library/windows/hardware/jj159305 > > This patch solves problem for ASUS N56VZ and ASUS N56VJ, both for > notification delivery and for brightness control. > > Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=52951 > Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=56711 > Reported-and-tested-by: Micael Dias <kam1kaz3@xxxxxxxxx> > Reported-and-tested-by: Dan Garton <dan.garton@xxxxxxxxx> > Reported-and-tested-by: Bob Ziuchkovski <bob.ziuchkovski@xxxxxxxxx> > Signed-off-by: Aaron Lu <aaron.lu@xxxxxxxxx> OK, do we need that in -stable and if so, which ones? Rafael > --- > drivers/acpi/video.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c > index b8299f2..f8fa541 100644 > --- a/drivers/acpi/video.c > +++ b/drivers/acpi/video.c > @@ -1543,12 +1543,12 @@ static int acpi_video_bus_put_devices(struct acpi_video_bus *video) > > 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, 1); > } > > 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, 0); > } > > static void acpi_video_bus_notify(struct acpi_device *device, u32 event) > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
