This was fixed for me but now has started reoccurring after updating to the beta. Linux kernel:
Linux rocinante 5.4.0-1002-oem #4-Ubuntu SMP Wed Jan 15 10:44:42 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1862835 Title: [Dell XPS 15 9570] Unable to change laptop screen brightness or keyboard backlighting Status in linux package in Ubuntu: Fix Committed Bug description: I am running a Dell XPS 15. Updating to 20.04 means that the keyboard bindings for changing the brightness and keypad backlighting don't work. The icons appear on the screen, but the brightness does not change. ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: xorg 1:7.7+19ubuntu14 ProcVersionSignature: Ubuntu 5.4.0-12.15-generic 5.4.8 Uname: Linux 5.4.0-12-generic x86_64 NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair ApportVersion: 2.20.11-0ubuntu16 Architecture: amd64 BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log' CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins' CompositorRunning: None CurrentDesktop: ubuntu:GNOME Date: Wed Feb 12 09:23:22 2020 DistUpgraded: 2020-02-08 14:25:17,407 DEBUG Running PostInstallScript: './xorg_fix_proprietary.py' DistroCodename: focal DistroVariant: ubuntu DkmsStatus: virtualbox, 6.1.2, 5.3.0-29-generic, x86_64: installed virtualbox, 6.1.2, 5.4.0-12-generic, x86_64: installed ExtraDebuggingInterest: Yes GraphicsCard: Intel Corporation UHD Graphics 630 (Mobile) [8086:3e9b] (prog-if 00 [VGA controller]) Subsystem: Dell UHD Graphics 630 (Mobile) [1028:087c] Subsystem: Dell GP107M [GeForce GTX 1050 Ti Mobile] [1028:087c] InstallationDate: Installed on 2018-11-21 (447 days ago) InstallationMedia: Ubuntu 18.10 "Cosmic Cuttlefish" - Release amd64 (20181017.3) MachineType: Dell Inc. XPS 15 9570 ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-12-generic root=UUID=78400725-c498-408a-af83-69891ddf09e4 ro quiet splash nouveau.modeset=0 acpi_osi=Linux vt.handoff=7 SourcePackage: xorg Symptom: display UpgradeStatus: Upgraded to focal on 2020-02-08 (3 days ago) dmi.bios.date: 11/08/2019 dmi.bios.vendor: Dell Inc. dmi.bios.version: 1.14.0 dmi.board.name: 0D0T05 dmi.board.vendor: Dell Inc. dmi.board.version: A00 dmi.chassis.type: 10 dmi.chassis.vendor: Dell Inc. dmi.modalias: dmi:bvnDellInc.:bvr1.14.0:bd11/08/2019:svnDellInc.:pnXPS159570:pvr:rvnDellInc.:rn0D0T05:rvrA00:cvnDellInc.:ct10:cvr: dmi.product.family: XPS dmi.product.name: XPS 15 9570 dmi.product.sku: 087C dmi.sys.vendor: Dell Inc. version.compiz: compiz N/A version.libdrm2: libdrm2 2.4.100+git2002011830.5c8ff5~oibaf~d version.libgl1-mesa-dri: libgl1-mesa-dri 20.1~git2002030730.a4e627~oibaf~d version.libgl1-mesa-glx: libgl1-mesa-glx 20.1~git2002030730.a4e627~oibaf~d version.xserver-xorg-core: xserver-xorg-core 2:1.20.7-2ubuntu1 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:19.1.0-1 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20190815-1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.16-1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1862835/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
