According to https://bugs.launchpad.net/stella/hwe-stella/+bug/1023760/comments/13 , the backlight function should work on 12.04 if BIOS fixed this issue.
But backlight function is still broken on 12.04(amd64, i386), 11.04 and 14.04. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1152544 Title: HP Envy 23 AIO - No way to dim display To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1152544/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
