On 07/15/2019 09:37 AM, andre_debian@... wrote:
> My computer laptop is Lenovo, video card Intel 520.
> 
> Only the Function keys F1 and F2 work for the sound, increase , decrease.
> 
> Package "thinkpad_acpi" doesn't exist on Debian.
> 
>

What is the output of :

  ls -al /sys/class/backlight/       ## note: / at end IS required

and if 'intel' or 'acpi_video0' is shwown, then what is the output of the one
present, e.g.

  ls -al /sys/class/backlight/intel/

or

  ls -al /sys/class/backlight/acpi_video0/

(in other words -- where is your backlight control coming from)


-- 
David C. Rankin, J.D.,P.E.