Running now the kernel form proposed and the backlight is working
$ uname -a Linux XPS-L322X 3.8.0-20-generic #31-Ubuntu SMP Mon May 6 17:03:32 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
I say "fixed"
Running now the kernel form proposed and the backlight is working
$ uname -a
Linux XPS-L322X 3.8.0-20-generic #31-Ubuntu SMP Mon May 6 17:03:32 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
I say "fixed"