[RESOLVED] Brightness settings not working

Hi, I followed this thread but wasn’t able to find something that worked.

I’m on Ubuntu Mate 22.04 (Jammy), 13th gen Framework with Intel graphics. Kernel is 5.15.0-89-generic.

After a long conversation with ChatGPT:

It appears that there are no backlight devices listed in the /sys/class/backlight/ directory on your system. This situation typically indicates one of the following scenarios:

  1. Graphics Driver Issue:
  • If the graphics drivers are not properly installed or are incompatible with your system, the backlight devices might not be correctly recognized. Ensure that your system has the correct drivers for your graphics hardware.
  1. Kernel Support:
  • The current Linux kernel you’re running might not support the backlight control for your specific hardware. This could be the case with certain newer laptops or specific graphics hardware.
  1. ACPI Issues:
  • The issue could be related to ACPI (Advanced Configuration and Power Interface) settings in the BIOS or UEFI firmware. Sometimes, changing certain settings in the BIOS/UEFI can help recognize hardware like backlight controllers.

Given these possibilities, here are some steps you can take:

  1. Check and Update Graphics Drivers:
  • Ensure that you have the correct drivers for your graphics card installed. You can do this by checking the “Additional Drivers” section in the “Software & Updates” settings.
  1. Update Your Kernel:
  • If your hardware is relatively new, updating to a newer Linux kernel might provide better support. However, updating the kernel can be a complex task and might lead to system instability, so it should be done with caution.
  1. ACPI Settings:
  • Check your BIOS/UEFI settings for any options related to ACPI and backlight control. Be cautious when changing BIOS/UEFI settings, as incorrect configurations can affect system stability.
  1. Search for Specific Solutions:
  • Look for solutions specific to your laptop model or hardware. Sometimes, manufacturers or communities may offer specific advice or patches for certain hardware.
  1. Seek Community Help:
  • Consider posting detailed information about your issue on Ubuntu forums or Ask Ubuntu. Include your laptop model, Ubuntu version, and any relevant output from terminal commands. The community might have insights specific to your hardware.

There aren’t any “Additional Drivers” available. I’m a little confused / hesitant about the other options. What should I do?

Hi @fundingmissions,

Distro and desktop is fine, kernel is very old (LTS or otherwise). For anything Ubuntu, you will want to be on OEM C.

You will want to follow the advanced guide, as the script is not laid out for Ubuntu MATE menu layout.

This will correctly address the backlight keys and getting you on a correct kernel for Framework 13th gen.


@Matt_Hartley This worked! Thank you!


Delighted to hear this, marking resolved.