On my just-released Dell XPS 13 Ultrabook, I can control the backlight with 'xbacklight -set 0' and 'xbacklight -set 100'. Any other values cause the screen to blink and flash. The keyboard backlight shortcuts don't work unless I map them to xbacklight 0 and 100. Also xbacklight doesn't work at all if I'm unplugged from AC. I've tried acpi_osi=Linux and acpi_backlight=vendor in grub.conf. acpi_osi doesn't seem to make any difference and xbacklight doesn't work at all without acpi_backlight. Do I just need to wait for a newer kernel?
- Grant
