On 05/18/2017 01:21 AM, Gregory Nowak wrote:
> On Wed, May 17, 2017 at 03:48:14PM +0300, Lars Noodén wrote:
>> Any hints would be appreciated.
>
> Did you try what I suggested:
> <https://lists.dyne.org/lurker/message/20170504.220911.f8f21b53.en.html>
>
> Greg

Yes, thanks, but that neither have any effect on the screen's backlight.

$ cat /proc/cmdline
BOOT_IMAGE=/boot/vmlinuz-3.16.0-4-amd64
root=UUID=5a117781-af00-4960-aff2-f711d5652784 ro acpi-backlight=vendor
acpi_osi=Linux

The keyboard backlight seems to work find regardless of the settings if
that's any clue.

/Lars