I am using ASUS X550J. All my fn functions are working fine(volume, touchpad,...) except brightness control(fn+f5/f6).
How can I fix this?
Run in a terminal
sudo -H gedit /etc/default/grub
And change the line
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=!"
Save the file, run
This will enable the Fn+F5 and F6 keys and also lid close/open events.
You may also need to redirect to
intel_backlight in X11 settings.
It can be done by adding
/usr/share/X11/xorg.conf.d/20-intel.conf with this content:
Section "Device" Identifier "card0" Driver "intel" Option "Backlight" "intel_backlight" BusID "PCI:0:2:0" EndSection