Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.2 kernel[0].
If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'. If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'. Once testing of the upstream kernel is complete, please mark this bug as "Confirmed". Thanks in advance. [0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.2-rc6-unstable/ ** Changed in: linux (Ubuntu) Importance: Undecided => Medium ** Changed in: linux (Ubuntu) Status: Confirmed => Incomplete -- 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/1483366 Title: Lenovo E540: Brightness control does not work Status in linux package in Ubuntu: Incomplete Bug description: After last Ubuntu updates, brightness control buttons stopped to work, brightness is stuck on maximum. When pressing key to reduce brightness, indicator shows up as it should, but doesn't let to reduce the indicator any step lower. Running Ubuntu 14.04 LTS. --- ApportVersion: 2.14.1-0ubuntu3.11 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: lenovou 2662 F.... pulseaudio /dev/snd/controlC1: lenovou 2662 F.... pulseaudio CurrentDesktop: Unity DistroRelease: Ubuntu 14.04 HibernationDevice: RESUME=UUID=0b3d8bde-fcba-4eb8-8ec0-9218338b66ad InstallationDate: Installed on 2015-02-14 (176 days ago) InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2) MachineType: LENOVO 20C6003QMS Package: linux (not installed) ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-61-generic root=UUID=c4dc0d94-61b2-4b8b-b547-79fea553646b ro quiet splash vt.handoff=7 ProcVersionSignature: Ubuntu 3.13.0-61.100-generic 3.13.11-ckt22 RelatedPackageVersions: linux-restricted-modules-3.13.0-61-generic N/A linux-backports-modules-3.13.0-61-generic N/A linux-firmware 1.127.14 Tags: trusty Uname: Linux 3.13.0-61-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo _MarkForUpload: True dmi.bios.date: 08/29/2014 dmi.bios.vendor: LENOVO dmi.bios.version: J9ET93WW (2.13 ) dmi.board.asset.tag: Not Available dmi.board.name: 20C6003QMS dmi.board.vendor: LENOVO dmi.board.version: 0B98401 WIN dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Not Available dmi.modalias: dmi:bvnLENOVO:bvrJ9ET93WW(2.13):bd08/29/2014:svnLENOVO:pn20C6003QMS:pvrThinkPadEdgeE540:rvnLENOVO:rn20C6003QMS:rvr0B98401WIN:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.name: 20C6003QMS dmi.product.version: ThinkPad Edge E540 dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1483366/+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