Public bug reported: With Unity I can change the backlight with the hotkeys out of the box, didn't had to do anything to get that working. I've now switched to Gnome (by installing ubuntu-gnome-desktop), but I've not found a way to get the hotkeys working for the backlight again. I also don't see the backlight slider in the upper right menu or in the settings.
I've tried everything on this page: https://wiki.ubuntu.com/Kernel/Debugging/Backlight I've tried different combinations in my grub configuration: video.use_native_backlight acpi_backlight=vendor acpi_backlight=none thinkpad-acpi.brightness_enable=1 acpi_backlight=vendor thinkpad-acpi.brightness_enable=1 acpi_backlight=none acpi_osi="!Windows 2012" acpi_osi=linux thinkpad-acpi.brightness_enable=1 acpi_osi= I've also added 'EnableBrightnessControl' to my xorg.conf. Unfortunately, nothing changes. And /sys/class/backlight/ is always empty. The only thing that did make a difference was adding 'acpi_os=' to my grub config. This did show the backlight slider in the settings & menu. And did show the pop-up when changing the backlight via the hotkeys. Unfortunately, it didn't change the backlight. And the slider didn't go futher than 5% or something. During all my tests xbacklight always worked. That's the only way to change my backlight in Gnome atm. Only when I added 'acpi_os=' xbacklight stopped working. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: linux-image-4.4.0-36-generic 4.4.0-36.55 ProcVersionSignature: Ubuntu 4.4.0-36.55-generic 4.4.16 Uname: Linux 4.4.0-36-generic x86_64 NonfreeKernelModules: nvidia_uvm nvidia_drm nvidia_modeset nvidia ApportVersion: 2.20.1-0ubuntu2.1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: tpater 2523 F.... pulseaudio /dev/snd/controlC0: tpater 2523 F.... pulseaudio CurrentDesktop: GNOME Date: Fri Sep 16 08:55:30 2016 EcryptfsInUse: Yes HibernationDevice: RESUME=UUID=3bb7a82d-4df4-43fb-9005-42cee745d105 InstallationDate: Installed on 2016-08-30 (17 days ago) InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719) MachineType: LENOVO 20ENCTO1WW ProcFB: 0 EFI VGA ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.4.0-36-generic.efi.signed root=/dev/mapper/ubuntu--vg-root ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-4.4.0-36-generic N/A linux-backports-modules-4.4.0-36-generic N/A linux-firmware 1.157.3 SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 08/03/2016 dmi.bios.vendor: LENOVO dmi.bios.version: N1EET57W (1.30 ) dmi.board.asset.tag: Not Available dmi.board.name: 20ENCTO1WW dmi.board.vendor: LENOVO dmi.board.version: SDK0J40709 WIN dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: None dmi.modalias: dmi:bvnLENOVO:bvrN1EET57W(1.30):bd08/03/2016:svnLENOVO:pn20ENCTO1WW:pvrThinkPadP50:rvnLENOVO:rn20ENCTO1WW:rvrSDK0J40709WIN:cvnLENOVO:ct10:cvrNone: dmi.product.name: 20ENCTO1WW dmi.product.version: ThinkPad P50 dmi.sys.vendor: LENOVO ** Affects: linux (Ubuntu) Importance: Undecided Status: Confirmed ** Tags: amd64 apport-bug xenial -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1624234 Title: Changing backlight doesn't work in Gnome To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1624234/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
