Adapted from here.
Get Fn F5/F6 working:
sudo emacs etc/default/grub
Change the following: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi="
sudo update-grub
reboot the system... Now the splash screen should show up.
Verify acpi commands with acpi_listen:
acpi_listen.
press Fn F5/F6. I got this:
video/brightnessdown BRTDN 00000087 00000000 K
video/brightnessup BRTUP 00000086 00000000 K
Add the event codes to acpi event:
sudo emacs /etc/acpi/events/asus-keyboard-backlight-down
event=video/brightnessdown BRTDN 00000087
sudo emacs /etc/acpi/events/asus-keyboard-backlight-up
event=video/brightnessup BRTUP 00000086
Confirm you can change backlight by (where xx is an integer):
echo xx | sudo tee /sys/class/backlight/intel_backlight/brightness
Add the link to the script:
sudo emacs /etc/acpi/asus-keyboard-backlight.sh
KEYS_DIR=/sys/class/backlight/intel_backlight
I also set value to 10 instead of 1, as it was just too slow:
# Get increment of x/10, this allows the brightness to map to the bar.
# If your bar somehow has other than 10 steps, just change the '10' here to the number of steps.
inc=$((MAX/10))
INCREMENT=${inc%.*}
if [ "$1" = down ]; then
VAL=$((VAL-INCREMENT))
else
VAL=$((VAL+INCREMENT))
fi
You'll need to restart acpid for it to take effect:
sudo service acpid restart