Yesterday I performed a clean install of Ubuntu 16.04 LTS Xenial Xersus on my 5 year old Hewlett-Packard Laptop powered by Intel Core i3 2nd-Gen Processors and AMD Radeon Graphics. Everything went smooth, and once the installation was complete and all the obsolete packages were removed, I logged in and damn, the brightness was way too high. So, I tried reducing it through the control buttons on my keyboard but in vain. Only then I realized that something was amiss – the brightness function keys weren’t working!
Did a quick search on DuckDuckGo and came up across this link by Abhishek Prakash of It’s F.O.S.S.
I tried the below method and it worked fine for me :
Open terminal and create the following configuration file, if it doesn’t exist:
sudo touch /usr/share/X11/xorg.conf.d/20-intel.conf
Now we need to edit this file. You can use any editor be it a terminal one or graphical.
sudo gedit /usr/share/X11/xorg.conf.d/20-intel.conf
Add the following lines to this file:
Section "Device" Identifier "card0" Driver "intel" Option "Backlight" "intel_backlight" BusID "PCI:0:2:0" EndSection
Save it. Log out and log back in. The brightness control should now be working through the function keys.
Hope that helps. Remember, I’m using Intel processors and my graphics card is powered by AMD and NOT Nvidia.