I am trying to get the LCD backlight brightness control to work properly on my new ASUS G75VW-DH72 laptop in Ubuntu 12.10. I got it to mostly work by following the instructions that I wrote here (acpi_osi=Linux acpi_backlight=vendor, EnableBrightnessControl=1). However, there are still two issues:
The main issue is that I have to press the hotkey (fn+F5 or fn+F6) TWICE before there is any effect on the brightness, or any output in the
acpi_listen command. So if I run
acpi_listen and press fn+F6 six times, the output only has three lines:
video LCDD 00000086 00000000 video LCDD 00000086 00000000 video LCDD 00000086 00000000
What causes this? How can I fix it? This behavior doesn't happen in Windows.
(Also, I noticed that the brightness is incrementing/decrementing in steps of 2 instead of 1, unless I happen to have a menu open. Any advice on that is welcome.)