Thank you, I'll see the best way to change it.
Currently the only way I now to change my LCD backlight is using setpci command. I wrote a simple script to get a two digit hex number (0 to ff) from input and set LCD backlight accordingly. The script is as follows:
if [ $# -eq 0 ]; then
sudo setpci -s 00:02.0 f4.b=ff
else
sudo setpci -s 00:02.0 f4.b=$1
fi
Buy any idea on how to fix the issue in order to get KDE mean of backlight setting to work is highly appreciated.