Display brightness on internal monitor is set to minimum and can't be changed after plugin out the external monitor.

[Didier Roche-Tolomelli]

I can reproduce it approx on 2 of 3 trials.

1. Get the brightness up (not minimum) of the internal monitor
2. Have an external monitor plugged in in the VGA cable
3. unplug the external monitor
-> the brightness of the internal monitor is set to minimum
-> the fn keys to change the brightness don't work anymore (you are stuck to minimum brightness)

workaround:
- replug the external monitor and unplug it again
-> then, you can most of the time, change the internal monitor brightness through the Fn keys.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: linux-image-3.13.0-12-generic 3.13.0-12.32
ProcVersionSignature: Ubuntu 3.13.0-12.32-generic 3.13.4
Uname: Linux 3.13.0-12-generic x86_64
ApportVersion: 2.13.2-0ubuntu5
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: didrocks 2685 F.... pulseaudio
CurrentDesktop: Unity
Date: Wed Feb 26 15:11:38 2014
EcryptfsInUse: Yes
HibernationDevice: RESUME=UUID=721253a1-6e55-4181-bc64-506c5987a191
InstallationDate: Installed on 2012-05-28 (639 days ago)
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425)
MachineType: LENOVO 4287CTO
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-12-generic root=UUID=a9f4b475-e4ce-45ed-aa33-9b92e52c49b0 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-12-generic N/A
 linux-backports-modules-3.13.0-12-generic N/A
 linux-firmware 1.125
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
WifiSyslog:

dmi.bios.date: 02/14/2012
dmi.bios.vendor: LENOVO
dmi.bios.version: 8DET58WW (1.28 )
dmi.board.asset.tag: Not Available
dmi.board.name: 4287CTO
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:bvr8DET58WW(1.28):bd02/14/2012:svnLENOVO:pn4287CTO:pvrThinkPadX220:rvnLENOVO:rn4287CTO:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 4287CTO
dmi.product.version: ThinkPad X220
dmi.sys.vendor: LENOVO

[Brad Figg (brad-figg)]

This change was made by a bot.

[Joseph Salisbury (jsalisbury)]

Did this issue occur in a previous version of Ubuntu, or is this a new issue?

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v3.13 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'.

If you are unable to test the mainline kernel, for example it will not boot, please add the tag: 'kernel-unable-to-test-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/v3.14-rc4-trusty/

[Launchpad Janitor (janitor)]

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