[oneiric] backlight always stays on

[Eugene San]

After switch to Oneiric backlight of LCD screen always stays on.

* When screen configured to shut down after being idle, it fades out (to blank black screen), but backlight stays on.
* Backlight control from keyboard is fully functional.
* Reconstructible on GMA945 and GMA965.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: xorg 1:7.6+7ubuntu7
ProcVersionSignature: Ubuntu 3.0.0-10.16-generic-pae 3.0.4
Uname: Linux 3.0.0-10-generic-pae i686
.tmp.unity.support.test.0:

ApportVersion: 1.22.1-0ubuntu2
Architecture: i386
CompizPlugins: [core,bailer,detection,composite,opengl,decor,mousepoll,vpswitch,regex,animation,snap,expo,move,compiztoolbox,place,grid,imgpng,gnomecompat,wall,ezoom,workarounds,resize,fade,unitymtgrabhandles,scale,session,unityshell]
CompositorRunning: None
Date: Sun Sep 11 16:01:12 2011
DistUpgraded: Fresh install
DistroCodename: oneiric
DistroVariant: ubuntu
DkmsStatus: virtualbox, 4.1.2, 3.0.0-10-generic-pae, i686: installed
EcryptfsInUse: Yes
ExtraDebuggingInterest: Yes, whatever it takes to get this fixed in Ubuntu
GraphicsCard:
 Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller [8086:27a2] (rev 03) (prog-if 00 [VGA controller])
   Subsystem: Lenovo ThinkPad T60/R60 series [17aa:201a]
   Subsystem: Lenovo ThinkPad T60/R60 series [17aa:201a]
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Beta i386 (20110901)
MachineType: LENOVO 19524TG
PccardctlIdent:
 Socket 0:
   no product info available
PccardctlStatus:
 Socket 0:
   no card
ProcEnviron:
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.0.0-10-generic-pae root=UUID=b612f4f1-147a-447d-87dc-803b508eaa5f ro quiet splash pcie_aspm=force vt.handoff=7
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/01/2010
dmi.bios.vendor: LENOVO
dmi.bios.version: 79ETE6WW (2.26 )
dmi.board.name: 19524TG
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:bvr79ETE6WW(2.26):bd04/01/2010:svnLENOVO:pn19524TG:pvrThinkPadT60:rvnLENOVO:rn19524TG:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 19524TG
dmi.product.version: ThinkPad T60
dmi.sys.vendor: LENOVO
version.compiz: compiz 1:0.9.5.92+bzr2791-0ubuntu2
version.libdrm2: libdrm2 2.4.26-1ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 7.11-0ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 7.11-0ubuntu3
version.xserver-xorg: xserver-xorg 1:7.6+7ubuntu7
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.6.0-1ubuntu13
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20110811.g93fc084-0ubuntu1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.15.901-1ubuntu2
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20110411+8378443-1

[Eugene San (eugenesan)]

Fixed in Oneiric release

[Nishant (nishant-singh28)]

I still have the problem...although my notebook has a dedicated GPU. ATI Mobility Radeon HD4570

[Nishant (nishant-singh28)]

Running this command:
xset dpms force off
Turns the LCD and the backlight off no problem. The backlight only stays on when the display automatically turns off after a specified duration of activity, 3 minutes in my case.

[Nishant (nishant-singh28)]

Closing the lid does shut the display off completely, so I think the issue is in the method used by the power manager to put the display to sleep after idle.