I have the same issue on a Dell XPS 13 (L322X, Ivy Bridge model with 1080p display). - With 3.19.0-11-generic backlight is working fine. - With 3.19.0-12-generic, keyboard buttons produce notifications but the brightness is not changed. I can manually change it writing to '/sys/class/backlight/intel_backlight/brightness'. - I tested 4.0.0-040000rc7-generic from kernel-ppa/mainline and it is working fine, as 3.19.0-11-generic. With all kernels, when brightness is set to 0 the display (not only backlight) turn off, but I think it's another bug.
I'm available if more tests are needed to bisect the issue. ** Tags added: kernel-fixed-upstream kernel-fixed- upstream-3.19.0-11-generic ** Tags removed: kernel-fixed-upstream-3.19.0-11-generic ** Tags added: kernel-fixed-upstream-4.0.0-040000rc7 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1440270 Title: regression: backlight can't be adjusted on UX32VD with 3.19.0-12-generic kernel To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1440270/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
