Hello Ubuntu community,

I can control the brightness of my DELL U2713HM connected with DisplayPort via the command:

ddccontrol -p -r 0x10 -w 53

where in this example the number 53 represents the brightness level (range 0 to 100). But I don't know how to link the command to my brightness keys on my keyboard.

I searched already, but just found answers to integrated laptop screens. In /sys/class/backlight is the folder acpi_video0 with some subfolders and files. The file actual_brightness contains a number from 0 to 20, which is changing when I press the brightness keys.

How do I get my external monitor listed as a device in /sys/class/backlight ?

PS: I am running a fresh Ubuntu 12.10 install with integrated graphics Intel HD4000.