Keyboard backlight
Any vendor
You can control your computer keyboard backlight via the D-Bus interface. The benefits of using it are that no modification to device files is required and it is vendor agnostic.
Here is an example implementation in Python 3.
Install upower and python-dbus packages then place the following script in /usr/local/bin/
and make it executable. You can then map your keyboard shortcuts to run /usr/local/bin/kb-light.py + x
and /usr/local/bin/kb-light.py - x
to increase and decrease your keyboard backlight level by x
.
/usr/local/bin/kb-light.py
#!/usr/bin/env python3 import dbus import sys def kb_light_set(delta): bus = dbus.SystemBus() kbd_backlight_proxy = bus.get_object('org.freedesktop.UPower', '/org/freedesktop/UPower/KbdBacklight') kbd_backlight = dbus.Interface(kbd_backlight_proxy, 'org.freedesktop.UPower.KbdBacklight') current = kbd_backlight.GetBrightness() maximum = kbd_backlight.GetMaxBrightness() new = max(0, min(current + delta, maximum)) if 0 <= new <= maximum: current = new kbd_backlight.SetBrightness(current) # Return current backlight level percentage return 100 * current / maximum if __name__ == '__main__': if len(sys.argv) == 2 or len(sys.argv) == 3: if sys.argv[1] == "--up" or sys.argv[1] == "+": if len(sys.argv) == 3: print(kb_light_set(int(sys.argv[2]))) else: print(kb_light_set(17)) elif sys.argv[1] == "--down" or sys.argv[1] == "-": if len(sys.argv) == 3: print(kb_light_set(-int(sys.argv[2]))) else: print(kb_light_set(-17)) else: print("Unknown argument:", sys.argv[1]) else: print("Script takes one or two argument.", len(sys.argv) - 1, "arguments provided.")
Alternatively the following bash oneliner will set the backlight to the value specified in argument:
setKeyboardLight () { dbus-send --system --type=method_call --dest="org.freedesktop.UPower" "/org/freedesktop/UPower/KbdBacklight" "org.freedesktop.UPower.KbdBacklight.SetBrightness" int32:$1 }
Asus
The keyboard backlight file is usually locked out from editing. To unlock this file at bootup, you will need to create a systemd service.
/usr/lib/systemd/system/asus-kbd-backlight.service
[Unit] Description=Asus Keyboard Backlight Wants=systemd-backlight@leds:asus::kbd_backlight.service After=systemd-backlight@leds:asus::kbd_backlight.service [Service] Type=oneshot RemainAfterExit=yes ExecStart=/bin/chmod 666 /sys/class/leds/asus::kbd_backlight/brightness [Install] WantedBy=multi-user.target
You are now able to use a keyboard backlight changer script. For an example, see ASUS G55VW#keyboard backlight script.
For an example of how you might set up a tiny daemon (running as root) that edits these files, hook it up to dbus, and map the keyboard brightness keys to dbus method calls, see [1].