Comment 0 for bug 1178205

Hello,

see $SUBJECT. By default the screen is very dark and almost unreadable. The Fn+F6/7 hotkeys show the brightness applet but don't change the brightness. Attached info according to https://wiki.ubuntu.com/Kernel/Debugging/Backlight below.

Adding "acpi_backlight=vendor" as suggested boot parameters fixes this bug, but this requires manual GRUB configuration (not suitable for non-experts).

Regards
Jens

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: linux-image-3.2.0-41-generic-pae 3.2.0-41.66
ProcVersionSignature: Ubuntu 3.2.0-41.66-generic-pae 3.2.42
Uname: Linux 3.2.0-41-generic-pae i686
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24.
ApportVersion: 2.0.1-0ubuntu17.2
Architecture: i386
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 0: PCH [HDA Intel PCH], device 0: ALC269VB Analog [ALC269VB Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: ubuntu 1655 F.... pulseaudio
Card0.Amixer.info:
 Card hw:0 'PCH'/'HDA Intel PCH at 0xc4820000 irq 50'
   Mixer name : 'Intel CougarPoint HDMI'
   Components : 'HDA:10ec0269,11790628,00100100 HDA:80862805,11790001,00100000'
   Controls : 29
   Simple ctrls : 11
Date: Thu May 9 12:14:51 2013
HibernationDevice: RESUME=UUID=add8fe24-1f1e-4ca7-a2d6-a0f40c03383f
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release i386 (20120423)
MachineType: TOSHIBA TECRA R850
MarkForUpload: True
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.2.0-41-generic-pae root=UUID=ffc754ea-32ed-4ae7-b471-bca82bd54afb ro elevator=deadline quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.2.0-41-generic-pae N/A
 linux-backports-modules-3.2.0-41-generic-pae N/A
 linux-firmware 1.79.4
SourcePackage: linux
StagingDrivers: mei
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 08/25/2011
dmi.bios.vendor: TOSHIBA
dmi.bios.version: Version 3.10
dmi.board.asset.tag: 0000000000
dmi.board.name: Portable PC
dmi.board.vendor: TOSHIBA
dmi.board.version: Version A0
dmi.chassis.asset.tag: 0000000000
dmi.chassis.type: 10
dmi.chassis.vendor: TOSHIBA
dmi.chassis.version: Version 1.0
dmi.modalias: dmi:bvnTOSHIBA:bvrVersion3.10:bd08/25/2011:svnTOSHIBA:pnTECRAR850:pvrPT525E-043021GH:rvnTOSHIBA:rnPortablePC:rvrVersionA0:cvnTOSHIBA:ct10:cvrVersion1.0:
dmi.product.name: TECRA R850
dmi.product.version: PT525E-043021GH
dmi.sys.vendor: TOSHIBA