Gentoo Fluxbox Asus Keyboard backlight control

My Laptop is an Asus N56V and previously, using Gnome or KDE, everyone had something to control the backlight. Now, using Fluxbox, there’s nothing – but Fluxbox is awesome ! 🙂

Here’s how I’ve managed to control the backlight using fluxbox

Your’re going to need the following kernel modules:

asus_nb_wmi
asus_wmi

They’re found at:

Device Drivers ->

    X86 Platform Specific Device Drivers ->

        Asus Laptop Extras

        Asus WMI Driver ->

            Asus Notebook WMI Driver

After loading the modules, you should have the following directories:

cd /sys/devices/platform/asus-nb-wmi/leds/asus::kbd_backlight

and inside, files and directories. What we’re looking for are the files brightness and max_brightness. If you have those, then we’re ok !

Fabien Loison has developed a small program to work with the Asus keyboard backlight. Head over to http://projects.flogisoft.com/ and get the files for Asus Keyboard backlight. The latest version is 0.1

You can check the files here: http://projects.flogisoft.com/asus-keyboard-backlight/download/

Before untar and install, make sure you have the dependencies meet. Read the README file.

If you meet the dependencies, go ahead

tar -zxvf asus-kbd-backlight_0.1_src.tar.gz

cd asus-kbd-backlight-0.1

And, to install, as root:

./install.sh --install

Now, after installed, is necessary to change the location of the files (those in /sys/….)

vi /etc/init.d/asus-kbd-backlight

Change the path in the variable BRIGHTNESS_FILE

After is changed, add it to default runtime and start it

(I’m using openRC – If using systemd adjust accordingly)

rc-update asus-kbd-backlight default

/etc/init.d/asus-kbd-backlight start

Now, let’s see if is working:

Get the max brightness value

cat /sys/devices/platform/asus-nb-wmi/leds/asus::kbd_backlight/max_brightness

and some value should be returned – mine was 3

Get the current brightness value:

cat /sys/devices/platform/asus-nb-wmi/leds/asus::kbd_backlight/brightness

and a value shoud be returned – mine was 1

To change the brightness of the keyboard backlight, we just need to change the returned value of the brightness file with one between 0 and max_brightness. Our problem is that these files can only be written by root – but fluxbox is running with our user. Here enters sudo.

I’m not going to explain how sudo works – ArchWiki has a very nice tutorial on it. Just edit the file with visudo and uncomment the following line:

# Same thing without a password
 %wheel ALL=(ALL) NOPASSWD: ALL

For these to work, your user must be in the wheel group.

Increase and reduce brightness

Create the following files for reducing and increasing brightness

Increase brightness

[code language=”bash” title=”increase-brightness”]

#!/bin/bash
# Path to brightness files
# Replace the path with yours
bpath=/sys/devices/platform/asus-nb-wmi/leds/asus::kbd_backlight/brightness
# cat max_brightness in above path to discover the max_brightness
maxb=3
# Discover the current brightness
cur_b=`cat $bpath`
# if brigthness is less than max
if [ $cur_b -lt $maxb ]
then
      let cur_b++
fi
# Increase brightness
`sudo sh -c "echo $cur_b > $bpath"`
[/code]

Reduce brightness

[code language=”bash” title=”decrease-brightness”]

#!/bin/bash
# Path to brightness files
# Replace the path with yours
bpath=/sys/devices/platform/asus-nb-wmi/leds/asus::kbd_backlight/brightness
# Discover the current brightness
cur_b=`cat $bpath`
# if brigthness is less than max
if [ $cur_b -gt 0 ]
then
let cur_b–
fi
# Increase brightness
`sudo sh -c "echo $cur_b > $bpath"`

[/code]

Save the files, make them executable and remember the location

Using xev, discover the key codes for Fn + F3 (reduce brightness) and Fn + F4 (increase brightness)  or just create your own combination.

xev returns 237 for Fn + F3 and 238 for Fn + F4 – Those are the codes to use in keys file for fluxbox keyboard shortcuts

Edit yor fluxbox keys file – most likely in ~/.fluxbox/

Anywhere on the file,  add the following lines:

[code language=”bash”]

# Keyboard backlight brightness

# increase brightness

238 :Exec <file_path>/increase-brightness

# # decrease brightness
237 :Exec <file_path>/reduce-brightness

[/code]

Note: <file_path> is the location of the above two files

Save and reload fluxbox configuration

Now you can increase and reduce the brightness backlight of the keyboard in fluxbox