thinkpad screen dims after unplugging external display, and won't re-brighten without leaving X

[Nick Moffitt]

When I un-plug the external VGA cable from my Thinkpad X200s, the screen dims. Hitting Fn-Home (the brightness-increase key) does nothing. Suspending and resuming doesn't reset this, though a reboot will allow me to use the brightness controls again while in the POST and after.

My current workaround is that every time I disconnect the monitor, I have to C-M-F1 to get to a virtual console, brighten the screen, and then M-left to get back to X.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: compiz 1:0.9.11+14.04.20140310-0ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-17.37-generic 3.13.6
Uname: Linux 3.13.0-17-generic x86_64
.tmp.unity.support.test.0:

ApportVersion: 2.13.3-0ubuntu1
Architecture: amd64
CompizPlugins: [core,bailer,detection,composite,opengl,decor,snap,gnomecompat,grid,regex,mousepoll,compiztoolbox,resize,move,wall,animation,vpswitch,place,imgpng,workarounds,expo,fade,ezoom,session,scale,unityshell]
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
CurrentDesktop: Unity
Date: Wed Mar 12 13:22:01 2014
DistUpgraded: 2014-02-25 19:06:30,487 DEBUG enabling apt cron job
DistroCodename: trusty
DistroVariant: ubuntu
EcryptfsInUse: Yes
GraphicsCard:
 Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a42] (rev 07) (prog-if 00 [VGA controller])
   Subsystem: Lenovo Device [17aa:20e4]
   Subsystem: Lenovo Device [17aa:20e4]
MachineType: LENOVO 7465CTO
PackageArchitecture: all
ProcKernelCmdLine: root=UUID=5237fceb-23d0-412d-84d9-b8f8b3bf28af ro quiet splash
SourcePackage: compiz
UpgradeStatus: Upgraded to trusty on 2014-02-25 (14 days ago)
dmi.bios.date: 06/25/2009
dmi.bios.vendor: LENOVO
dmi.bios.version: 6DET55WW (3.05 )
dmi.board.name: 7465CTO
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:bvr6DET55WW(3.05):bd06/25/2009:svnLENOVO:pn7465CTO:pvrThinkPadX200s:rvnLENOVO:rn7465CTO:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 7465CTO
dmi.product.version: ThinkPad X200s
dmi.sys.vendor: LENOVO
version.compiz: compiz 1:0.9.11+14.04.20140310-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.52-1
version.libgl1-mesa-dri: libgl1-mesa-dri 10.1.0~rc3-0ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 10.1.0~rc3-0ubuntu3
version.xserver-xorg-core: xserver-xorg-core 2:1.15.0-1ubuntu6
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.8.2-1ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.3.0-1ubuntu3
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.910-0ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.10-1ubuntu2
xserver.bootTime: Wed Mar 12 09:07:01 2014
xserver.configfile: /etc/X11/xorg.conf
xserver.errors:

xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:
 product id 16404
 vendor LEN
xserver.version: 2:1.15.0-1ubuntu6

[Christopher Townsend (townsend)]

This sounds more like a kernel issue (ACPI maybe?) as Compiz has nothing to do with screen brightness and screen brightness hot keys.

[Brad Figg (brad-figg)]

This change was made by a bot.

[Joseph Salisbury (jsalisbury)]

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-rc6-trusty/

[Nick Moffitt (nick-moffitt)]

Joseph, your text says the latest v3.13 kernel, but the link takes me to v3.14. Is that correct?

[Nick Moffitt (nick-moffitt)]

Linux vezza 3.14.0-031400rc6-generic #201403100035 SMP Mon Mar 10 04:36:54 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux

The bug seems to be fixed with this kernel.

[Joseph Salisbury (jsalisbury)]

Yes, sorry. The test should have read the 3.14 kernel.

[Abhinav Jain (abhinav-jaine)]

i face same problem with thinkpad T430U using same work around of Ctrl+alt+ f1 to increase brightness and back with ctrl+alt+f7
the brightness controls are non responsive
i am running ubuntu 14.04 LTS. however my kernel is also 3.13.

[Anmar Oueja (anmar)]

I also confirm that problem continue to exists for Ubuntu 14.04 using th standard Linux X1 3.13.0-30-generic #54-Ubuntu SMP Mon Jun 9 22:45:01 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux kernel.

The way around it is to go the console, adjust the brightness to desired level, then go back to X. Brightness adjustment doesn't work at all when in X. Just console after I unplug the external monitor or reboot the entire machine.

[Reed O'Brien (reedobrien)]

I confirm it on a thinkpad x230 with stock kernels since 14.04. I reattach the external monitor then detach again which seems to consistently return the brightness controls to a working state.

[burabure (nccolas)]

I also confirm it on a thinkpad x230 with stock kernels since 14.04.

[Tony Burns (tabolario)]

I can also confirm this on a ThinkPad T540p with stock kernel (3.13.0-generic), and that the workaround is to drop into a console to adjust brightness and then go back to X.

[Mike Pontillo (mpontillo)]

FYI, I can confirm this on a Clevo W230SS. (It has both an nvidia an Intel chipset, but I keep it in Intel-only mode.) Let me know if I can do anything to assist.

[itsols (itsols)]

I'm using 14.04 on an HP ProBook 6460b.

I have the same issue.

It used to dim the laptop screen when the monitor is unplugged. Then plugging it in again and removing it brought the controls back.

As of today, even plugging the screen multiple times is not bringing back the controls. I really think we need this fixed.

Khalid

[Néstor A.C. (nestorac)]

I confirm this bug on ThinkPad X201. I don't remember the Ubuntu version.