G15 5525 - cannot control brightness

Hi, I have recently bought a G15 5525 with a Nvidia GeForce RTX 3060 Mobile graphic card. Just installed ubuntu 22.04 alongside with Windows, but I have two main problems:

• Screen flickers randomly.
• Brightness controls doesn’t work, either keyboard and in the OS. Specifically when turning brightness up/down, there is no effect (brightness is stuck at max).

Screen flickers seem to be fixed by installing 5.18 kernel (check discussion from Nvidia forums here), but it seems the brightess fail is due to the bios (see post #7) The output of 

ls /sys/class/backlight

is

amdgpu_bl0 nvidia_wmi_ec_backlight

where it should just be

amdgpu_bl0

Is there any way to fix this, or should I report it somewhere else? Thanks in advance!