Bug#438969: libxrandr2: Restoring the backlight uses inadequate values

[Brice Goglin <Brice.Goglin@ens-lyon.org>]

Thomas Prokosch wrote:
> Package: libxrandr2
> Version: 2:1.2.1-1
> Severity: normal
>
> I do have a Sony laptop, and I have mapped the function keys controlling
> the brightness of the display to a script setting values in
> /sys/class/backlight/sony. This works fine both in the console and
> within X up to the point where xscreensaver kicks in and sets the
> display to DPMS standby, suspend or off mode. After reactivating the
> computer the screensaver sets the brightness of the display using the
> xrandr extension not to the value the display brightness had before, but
> to the value which is still in memory. To make a long story short, xrandr
> should check the actual brightness of the display before it is changed.
>
> I am filing this bug against xrandr because the xbacklight tool shows the
> same behaviour, so I do not think that this is an xscreensaver problem.
> If I am wrong, please feel free to reassign the bug to another package.
>   

Do you have an intel board and use xserver-xorg-video-intel 2.1.1 ?
If so, the problem could be related to bug #438619, you should look at
this bug at let me know whether you reproduce the same symptoms with
driver 2.0 or 2.1.0 or latest git or latest git with the patch reverted.

thanks,
Brice