Brightness not adapting on Ubuntu 22 Thinkbook Gen 2


I am using a Thinkbook Gen 2 Laptop with Ubuntu 22 freshly installed.
I’m encountering the same problem as many other people: the brightness of my screen doesn’t change when using the corresponding keys and the brightness slider. So far no solution worked for me.
Interesting observation: under /sys/class/backlight I have 2 directories: amdgpu_bl0 and nvidia_0. The keys and the slider actually do change the values of the brightness in nvidia_0, but this has no effect on the hardware. Instead, when I change the values of brightness in amdgpu_bl0 by hand, the brightness of my screen actually changes!
Any thoughts about this and how to solve?

Thank you

Out of interest: what’s the content of “type” in both brightness directories?

@generix “raw” in both