I have sony vaio SVE151117F, ubuntu 12.10.I used to see brightness animation upon pressing Fn+F6,F5 but not actual brightness of screen. I have tried to implement as said in http://ubuntuforums.org/showthread.php?t=2086359 but now I cant even see the brightness level animation.There is no change in brightness level of screen as usual.
I tried below links too , but still problem persists. unable to change brightness settings in sony vaio e series laptop http://vaioubuntu.wordpress.com/2008/12/04/finally-a-brightness-how-to-for-vaio-fw-series/