I removed the nvidia driver (331.38) in order to avoid problems when installing the upstream kernel. This, however, seemed to fix the issue, because brightness control is now working with the noveau driver and the stock kernel. This would mean that this is actually a bug in the proprietary nvidia driver?
-- 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/1301580 Title: Backlight control does not work, but there are entries in /sys/class/backlight Status in “linux” package in Ubuntu: Incomplete Bug description: Backlight control doesn't work in Ubuntu 14.04 on a Lenovo Thinkpad T61. Neither using hotkeys nor the brightness applet. ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: linux-image-3.13.0-19-generic 3.13.0-19.40 [modified: boot/vmlinuz-3.13.0-19-generic] ProcVersionSignature: Ubuntu 3.13.0-19.40-generic 3.13.6 Uname: Linux 3.13.0-19-generic x86_64 NonfreeKernelModules: nvidia ApportVersion: 2.13.3-0ubuntu1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: tommi 1964 F.... pulseaudio CurrentDesktop: Unity Date: Wed Apr 2 22:53:56 2014 HibernationDevice: RESUME=UUID=3e4b62ed-a926-47a3-ae19-44b96d1376ee InstallationDate: Installed on 2014-03-30 (3 days ago) InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Beta amd64 (20140326) MachineType: LENOVO 645745G PccardctlIdent: Socket 0: no product info available PccardctlStatus: Socket 0: no card ProcFB: ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.13.0-19-generic root=UUID=01d49c75-94f4-417c-beae-d16fd8b8df83 ro quiet splash RelatedPackageVersions: linux-restricted-modules-3.13.0-19-generic N/A linux-backports-modules-3.13.0-19-generic N/A linux-firmware 1.126 SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 12/06/2007 dmi.bios.vendor: LENOVO dmi.bios.version: 7LETA7WW (2.07 ) dmi.board.name: 645745G dmi.board.vendor: LENOVO dmi.board.version: Not Available dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Not Available dmi.modalias: dmi:bvnLENOVO:bvr7LETA7WW(2.07):bd12/06/2007:svnLENOVO:pn645745G:pvrThinkPadT61:rvnLENOVO:rn645745G:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.name: 645745G dmi.product.version: ThinkPad T61 dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1301580/+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
