OLED screen brightness control not working on Fedora 40 WS

Hi everybody,
It’s my first post here so please be kind :slight_smile:

I’ve just bought a brand new laptop Lenovo legion 5 slim 14.5" with a 2.8k OLED screen.

I’ve noticed that in Fedora 40 ( both default with gnome and KDE version ) the brightness control of my OLED screen doesn’t work.

It does instead in Ubuntu 24.04 out of the box.

I’ve understood that OLED screen has PWM to perform brightness control (mine has a 240hz PWM) that do not use the kernel backlight driver.

So, now: how can I figure out what is installed in Ubuntu take makes everything works out of the box?
Kernel in Ubuntu 6.8.0, fedora 6.8.11 so even newer.

I really need to use fedora, cannot use Ubuntu, but in this way the screen is unusable…

Thanks so much to anyone that can point me in the right direction.