It seems adding only one kernel parameter "acpi_backlight=vendor" also works on my G360 now. But, both methods of adding kernel parameters will stop work occasionly.
The detail of my case see: Bug 44809 - [Arrandale backlight] Brightness via RANDR has no effect on Sony VAIO VPCYA1V9E: https://bugs.freedesktop.org/show_bug.cgi?id=44809 2012/6/12 littlebat <dashing.m...@gmail.com> > Added "acpi_backlight=vendor acpi_osi=linux video.brightness_switch_enabled=1" > into grub boot kernel parameters, "Fn + Up/Down" to change brigtness works on > my G360. It's no need to write a Udev rules like my previous method. > >
