I can't change my brightness on my laptop and I would like a help to solve this problem.
Using kcmshell4 kgamma
I can change the constrast. But using xbacklight
nothing happens.
If I put
xbacklight -get
I got a value, for example, 86.666667
, but when I try
xbacklight -dec 40
Nothing happens.
The strange thing is that commands above (xbacklight -dec 40
) can work if I suspend my session and reopen it again.
How can I solve this?