This appears to be quite an old issue with Optimus graphics. For me the workaround was to pass specific kernel parameters at boot time to inhibit acpi control of the backlight but allow intel_backlight control I followed the instructions at https://nisheetlall.wordpress.com/2016/07/12/solved-brightness-fix-in-linux-for-optimus-laptops/ which worked first time for me. Your mileage may of course vary - it happens that I have exactly the same Lenovo Z570 laptop as the author of those instructions.
-- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1724933 Title: I can't adjust display brightness Status in xorg package in Ubuntu: Confirmed Bug description: I'm using HP Pavilion DV6. After upgrade to Ubuntu 17.10 from 17.04 I can't adjust display brightness. when I press F2|F3 keys icon brightness appears, the controller moves but the brightness doesn't change. ProblemType: Bug DistroRelease: Ubuntu 17.10 Package: xorg 1:7.7+19ubuntu3 ProcVersionSignature: Ubuntu 4.13.0-16.19-generic 4.13.4 Uname: Linux 4.13.0-16-generic x86_64 NonfreeKernelModules: wl .tmp.unity_support_test.0: ApportVersion: 2.20.7-0ubuntu3 Architecture: amd64 CompositorRunning: None CurrentDesktop: ubuntu:GNOME Date: Thu Oct 19 22:14:51 2017 DistUpgraded: 2017-10-19 21:15:33,861 DEBUG Running PostInstallScript: './xorg_fix_proprietary.py' DistroCodename: artful DistroVariant: ubuntu DkmsStatus: bcmwl, 6.30.223.271+bdcom, 4.10.0-37-generic, x86_64: installed bcmwl, 6.30.223.271+bdcom, 4.13.0-16-generic, x86_64: installed ExtraDebuggingInterest: Yes GraphicsCard: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0116] (rev 09) (prog-if 00 [VGA controller]) Subsystem: Hewlett-Packard Company 2nd Generation Core Processor Family Integrated Graphics Controller [103c:3388] Advanced Micro Devices, Inc. [AMD/ATI] Whistler [Radeon HD 6730M/6770M/7690M XT] [1002:6740] (rev ff) (prog-if ff) InstallationDate: Installed on 2017-06-18 (123 days ago) InstallationMedia: Ubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412) MachineType: Hewlett-Packard HP Pavilion dv6 Notebook PC ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.13.0-16-generic root=/dev/mapper/ubuntu--vg-root ro quiet splash vt.handoff=7 SourcePackage: xorg Symptom: display UpgradeStatus: Upgraded to artful on 2017-10-19 (0 days ago) dmi.bios.date: 04/25/2011 dmi.bios.vendor: Hewlett-Packard dmi.bios.version: F.13 dmi.board.asset.tag: Base Board Asset Tag dmi.board.name: 3388 dmi.board.vendor: Hewlett-Packard dmi.board.version: 10.25 dmi.chassis.asset.tag: Chassis Asset Tag dmi.chassis.type: 10 dmi.chassis.vendor: Hewlett-Packard dmi.chassis.version: Chassis Version dmi.modalias: dmi:bvnHewlett-Packard:bvrF.13:bd04/25/2011:svnHewlett-Packard:pnHPPaviliondv6NotebookPC:pvr058F110000244710000610100:rvnHewlett-Packard:rn3388:rvr10.25:cvnHewlett-Packard:ct10:cvrChassisVersion: dmi.product.family: 103C_5335KV G=N L=CON B=HP S=PAV dmi.product.name: HP Pavilion dv6 Notebook PC dmi.product.version: 058F110000244710000610100 dmi.sys.vendor: Hewlett-Packard version.compiz: compiz 1:0.9.13.1+17.10.20170901-0ubuntu1 version.libdrm2: libdrm2 2.4.83-1 version.libgl1-mesa-dri: libgl1-mesa-dri 17.2.2-0ubuntu1 version.libgl1-mesa-glx: libgl1-mesa-glx 17.2.2-0ubuntu1 version.xserver-xorg-core: xserver-xorg-core 2:1.19.5-0ubuntu2 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.10.0-1 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20170309-0ubuntu1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-2 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1724933/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp