kernel-packages team mailing list archive

[Nicolas Devillers <devillers.nicolas@xxxxxxxxx>]

xrandr --output [yourscreendevice] --set Backlight 80

However, in my case (maybe because I have 2 video adapter [cpu/amd] )
the latter xrandr command is equivalent to write in
/sys/class/backlight/acpi_video0/brightness which doesn't work.

** Changed in: linux (Ubuntu)
       Status: Expired => Confirmed

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1225811

Title:
  1002:6601 [Dell Inspiron 15R 5521] Can't toggle backlight brightness

Status in “linux” package in Ubuntu:
  Confirmed

Bug description:
  Since raring at least, it is not possible to change backlight
  brightness.

  WORKAROUND: Add acpi_backlight=vendor into grub boot option.

  ProblemType: Bug
  DistroRelease: Ubuntu 13.10
  Package: linux-image-generic 3.11.0.7.8
  ProcVersionSignature: Ubuntu 3.11.0-5.11-generic 3.11.0
  Uname: Linux 3.11.0-5-generic x86_64
  ApportVersion: 2.12.1-0ubuntu4
  Architecture: amd64
  AudioDevicesInUse:
   USER        PID ACCESS COMMAND
   /dev/snd/controlC0:  nicolas    2839 F.... pulseaudio
  Date: Mon Sep 16 02:05:10 2013
  EcryptfsInUse: Yes
  HibernationDevice: RESUME=UUID=173db09c-bffc-4da9-ab42-7ca73f84e71f
  InstallationDate: Installed on 2013-04-08 (160 days ago)
  InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Release amd64 (20121017.5)
  MachineType: Dell Inc. Inspiron 5521
  MarkForUpload: True
  ProcFB:
   0 inteldrmfb
   1 radeondrmfb
  ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.11.0-5-generic root=UUID=09af3e13-8004-48fa-b0fe-116acbf8d3d7 ro crashkernel=384M-2G:64M,2G-:128M quiet splash acpi_backlight=vendor vt.handoff=7
  RelatedPackageVersions:
   linux-restricted-modules-3.11.0-5-generic N/A
   linux-backports-modules-3.11.0-5-generic  N/A
   linux-firmware                            1.114
  SourcePackage: linux
  StagingDrivers: rts5139
  UpgradeStatus: Upgraded to saucy on 2013-06-24 (83 days ago)
  dmi.bios.date: 06/25/2013
  dmi.bios.vendor: Dell Inc.
  dmi.bios.version: A09
  dmi.board.name: 0HK2KG
  dmi.board.vendor: Dell Inc.
  dmi.board.version: A00
  dmi.chassis.type: 8
  dmi.chassis.vendor: Dell Inc.
  dmi.chassis.version: A09
  dmi.modalias: dmi:bvnDellInc.:bvrA09:bd06/25/2013:svnDellInc.:pnInspiron5521:pvrA09:rvnDellInc.:rn0HK2KG:rvrA00:cvnDellInc.:ct8:cvrA09:
  dmi.product.name: Inspiron 5521
  dmi.product.version: A09
  dmi.sys.vendor: Dell Inc.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1225811/+subscriptions