[Lenovo ThinkPad X220] Brightness to minimum and controls disabled when undocking

[Roger Kind Kristiansen]

To reproduce, remove the X220 from the dock. The brightness is set to minimum (the screen is nearly unreadable) and the brightness control is broken, you can't adjust it by hardware keys.

The symptom is fixed by docking and undocking again.

This is the same problem as discussed https://bugs.launchpad.net/linux/+bug/1308674/, where I was asked to open this new report.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: linux-image-3.13.0-36-generic 3.13.0-36.63
ProcVersionSignature: Ubuntu 3.13.0-36.63-generic 3.13.11.6
Uname: Linux 3.13.0-36-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.4
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: rkk 2514 F.... pulseaudio
CurrentDesktop: Unity
Date: Sat Oct 4 14:40:20 2014
EcryptfsInUse: Yes
InstallationDate: Installed on 2011-12-01 (1037 days ago)
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
MachineType: LENOVO 42914CG
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-36-generic root=UUID=36e15617-ebcb-47e7-9c57-582dda4bb198 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-36-generic N/A
 linux-backports-modules-3.13.0-36-generic N/A
 linux-firmware 1.127.7
SourcePackage: linux
UpgradeStatus: Upgraded to trusty on 2014-08-24 (41 days ago)
dmi.bios.date: 07/18/2013
dmi.bios.vendor: LENOVO
dmi.bios.version: 8DET69WW (1.39 )
dmi.board.asset.tag: Not Available
dmi.board.name: 42914CG
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:bvr8DET69WW(1.39):bd07/18/2013:svnLENOVO:pn42914CG:pvrThinkPadX220:rvnLENOVO:rn42914CG:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 42914CG
dmi.product.version: ThinkPad X220
dmi.sys.vendor: LENOVO

[Brad Figg (brad-figg)]

This change was made by a bot.

[penalvch (penalvch)]

Roger Kind Kristiansen, thank you for reporting this and helping make Ubuntu better. Could you please test the latest upstream kernel available from the very top line at the top of the page (not the daily folder) following https://wiki.ubuntu.com/KernelMainlineBuilds ? It will allow additional upstream developers to examine the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this bug is fixed in the mainline kernel, please add the following tags:
kernel-fixed-upstream
kernel-fixed-upstream-VERSION-NUMBER

where VERSION-NUMBER is the version number of the kernel you tested exactly shown as:
kernel-fixed-upstream-3.17-rc6

This can be done by clicking on the yellow circle with a black pencil icon next to the word Tags located at the bottom of the bug description.

If the mainline kernel does not fix this bug, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-VERSION-NUMBER

Once testing of the upstream kernel is complete, please mark this bug's Status as Confirmed. Please let us know your results. Thank you for your understanding.

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]