Public bug reported: 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 ** Affects: linux (Ubuntu) Importance: Undecided Status: Confirmed ** Tags: amd64 apport-bug precise running-unity ** Attachment added: "acpi" https://bugs.launchpad.net/bugs/1211056/+attachment/3768358/+files/acpi -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1211056 Title: Backlight off after power failure on Lenovo Thinkpad SL510 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1211056/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
