Lenovo P52, screen brightness adjustment does not work

[alfonz19]

Hi,

I'm just installed ubuntu 18.04 + cinnamon on Lenovo P52, but it seems that screen brightness does not work. I don't see any control anywhere, and "brightness multimedia keys" does not work. Other like changing volume/wifi do work. So I thought, that maybe just the buttons does not work and reassigned them, but that does not fix anything. I saw, that in some older versions one has to put something into grub so brightness can be adjusted, but that was targeted for much older versions, so I'm asking again, for cinnamon 4.0.9

can someone help?

thanks.

[alfonz19]

ignore that question. xbacklight command can be used as a workaround, and using it only visual feedback is missing. That's fine.

thanks.