On Mon, Dec 26, 2011 at 10:49 AM, Corentin Chary wrote: > On Sat, Dec 24, 2011 at 3:28 PM, David Herrmann > wrote: >> On Sat, Dec 24, 2011 at 3:20 PM, Matthew Garrett wrote: >>> On Sat, Dec 24, 2011 at 02:12:57PM +0000, Andrzej Prochyra wrote: >>>> 'acpi_video0' not functional.  Brightness can be controlled through >>>> intel_backlight interface.  There are 21 brightness levels and the >>>> backlight can be turned off. >>> >>> If acpi_video0 doesn't work then we either need to work out why it's not >>> working or make it vanish completely, so this patch isn't the correct >>> approach. >> >> Just to make clear, intel_backlight isn't working properly either. If >> my laptop boots with backlight at 50% then intel_backlight will only >> work in the range 0%-50% on my machine. If I use the samsung module to >> set it to 100% then  intel_backlight works correctly in the range >> 0-100% until next reboot/suspend. >> >> So I'd recommend staying with the samsung module and disabling the >> acpi_backlight entirely. The samsung module is the only backlight >> control which works properly. > > Can I take a look at the DSDT to see how it's broken ? > If it's really not functional, then it should be added to the > blacklist in video_detect.c Raw and disassembled dsdt is attached. Cheers David