Recently, there was a power failure (i.e., the laptop ran on battery until that was empty) and subsequently shut down. I did not manage to rewake it again (after reestablishing the power supply), so I had to turn it off completely and reboot. The result is that the backlight is off. The LCD is still working normally (i.e., I can barely make out some contours in reflectance), as are external monitors (both VGA and HDMI work). When using the brightness hot-keys, the notification shows up (correctly indicating the change in brightness), but the backlight remains off, no matter what I do. I also tried xbacklight, /sys/class/backlight/..., setpci, etc., but to no avail.
Following the guideline at https://wiki.ubuntu.com/Kernel/Debugging/Backlight, I'm attaching the requested files. Changing the various acpi_* kernel boot parameters showed no change (except that the brightness controls changed to 7 instead of 15 different settings).
BTW: Booting into Windows showed the same effect. Also, during boot, the backlight is off and the external monitor is not getting a signal, so I can't check the bios.
ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: linux-image-3.2.0-45-generic 3.2.0-45.70
ProcVersionSignature: Ubuntu 3.2.0-45.70-generic 3.2.44
Uname: Linux 3.2.0-45-generic x86_64
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24.
ApportVersion: 2.0.1-0ubuntu17.4
Architecture: amd64
ArecordDevices:
**** List of CAPTURE Hardware Devices ****
card 0: Intel [HDA Intel], device 0: ALC269 Analog [ALC269 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/controlC1: stefan 2587 F.... pulseaudio
/dev/snd/controlC0: stefan 2587 F.... pulseaudio
Card0.Amixer.info:
Card hw:0 'Intel'/'HDA Intel at 0xf2600000 irq 50'
Mixer name : 'Realtek ALC269'
Components : 'HDA:10ec0269,17aa212c,00100004'
Controls : 16
Simple ctrls : 9
Card1.Amixer.info:
Card hw:1 'HDMI'/'HDA ATI HDMI at 0xf2110000 irq 52'
Mixer name : 'ATI R6xx HDMI'
Components : 'HDA:1002aa01,00aa0100,00100100'
Controls : 6
Simple ctrls : 1
Card1.Amixer.values:
Simple mixer control 'IEC958',0
Capabilities: pswitch pswitch-joined penum
Playback channels: Mono
Mono: Playback [on]
Card29.Amixer.info:
Card hw:29 'ThinkPadEC'/'ThinkPad Console Audio Control at EC reg 0x30, fw 6JHT64WW-1.184000'
Mixer name : 'ThinkPad EC 6JHT64WW-1.184000'
Components : ''
Controls : 1
Simple ctrls : 1
Card29.Amixer.values:
Simple mixer control 'Console',0
Capabilities: pswitch pswitch-joined penum
Playback channels: Mono
Mono: Playback [on]
Date: Sun Aug 11 21:36:26 2013
HibernationDevice: RESUME=UUID=79a6911e-e43c-4f76-9fd6-d0d1734b85e4
InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release amd64 (20091027)
MachineType: LENOVO 28476NG
MarkForUpload: True
ProcEnviron:
LANGUAGE=de_DE:en
TERM=xterm
PATH=(custom, no user)
LANG=de_DE.UTF-8
SHELL=/bin/bash
ProcFB:
0 radeondrmfb
1 VESA VGA
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.2.0-45-generic root=UUID=0a0d615b-8dd8-4478-8940-94e2d3eb0fd0 ro quiet splash vga=792 acpi_osi=Linux
RelatedPackageVersions:
linux-restricted-modules-3.2.0-45-generic N/A
linux-backports-modules-3.2.0-45-generic N/A
linux-firmware 1.79.6
SourcePackage: linux
UpgradeStatus: Upgraded to precise on 2012-05-03 (465 days ago)
dmi.bios.date: 06/24/2010
dmi.bios.vendor: LENOVO
dmi.bios.version: 6JET81WW (1.39 )
dmi.board.name: 28476NG
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:bvr6JET81WW(1.39):bd06/24/2010:svnLENOVO:pn28476NG:pvrThinkPadSL510:rvnLENOVO:rn28476NG:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 28476NG
dmi.product.version: ThinkPad SL510
dmi.sys.vendor: LENOVO
This change was made by a bot.