I have a Lenovo Legion 5 pro (2021), I tried installing ubuntu 20.04.

The problem is that I can't seem to change the brightness at all, it is at max.

Laptop Spec

**Processor** 

    AMD Ryzen™ 7 5800H Processor (8 Cores / 16 Threads, 3.20 GHz, up to 4.40 GHz with Max Boost, 4 MB Cache L2 / 16 MB Cache L3)

**Display Type**

    40.64cms (16.0) WQXGA (2560x1600) IPS 500nits Anti-glare 165Hz 100% sRGB Dolby Vision HDR 400 Free-Sync G-Sync DC Dimmer

***Memory*** 

    16 GB SO-DIMM DDR4 3200MHz

**Graphics** 

    NVIDIA® GeForce RTX™ 3060 6GB GDDR6

**Wireless**

    Wi-Fi 6, 802.11ax 2x2 Wi-Fi + Bluetooth® 5.1, M.2 Card

Just scroll down and you will see the details of the laptop, mine is with RTX 3060.

Any kind of help is appreciated, I have also heard that upgrading to ubuntu 21.04 helps?

Edit
There is a hack that works xrandr --output DP-4 --brightness 0.5 but again this is a temporary solution and the controller still does not work.

I also tried to change xorg.conf file, i simply added.

Option "RegistryDwords" "EnableBrightnessControl=1"

It did not work. :,)

Edit
More weirdness, now the xrandr hack gets disabled automatically and I have to run it again and again.

On top of the if the session gets suspended, the screen does not come back, like it stays blank and sometimes it comes back but it is very very dim. Not sure what's happening there.

Edit (5/12/21)
I have started to use the AMD GPU to save power while using the laptop but the issue is not fixed.