Driver 510 breaks brightness control

[Simone Lussardi]

Hello,

The 510 driver breaks brightness control. Was working fine with 495, after an update & reboot, it got stuck at high luminosity. The brightness adjusting key works, but brightness never changes. I have tried a few solutions found online (adding modules to initramfs-tools/modules, editing X11 files, etc.), but nothing works.

My laptop has switchable graphics. If I switch to fully AMD, brightness comes back. Also, it has self adjusting brightness, with camera light sensor. Curiously, also that one stopped working after the update.

Lenovo ThinkBook 16p Gen 2 (32G RAM)
Ubuntu 20.04.3 LTS
AMD® Ryzen 9 5900hx with radeon graphics × 16
NVIDIA GeForce RTX 3060 Laptop GPU
Kernel 5.13.0-28-generic

Cheers,
Simone

[Simone Lussardi (simone-lussardi)]

I've also checked the content of /sys/class/backlight, and all is correct. If I run sudo cat /sys/class/backlight/nvidia_0/brightness, brightness value changes according to what the computer set. Just, the thing itself is not set trough the screen. Also another note: I try adding kernel parameters to boot, nothing. It still isn't working.

I admit it may be a rare laptop mine, but I think other have RTX/AMD combo.

Cheers,
Simone

[Simone Lussardi (simone-lussardi)]

..... Is it possible that I am the only one with this bug ? It renders the usage of the computer pretty much very bad, on battery the brightness goes down, and doesn't go up anymore....

I've also recently upgraded the default Ubuntu graphic driver set, but it doesn't change anything.

If you guys need more info, I am very happy to help.

Cheers,
Simone