I upgraded BIOS to the last available versión (2.12) and brightness control seems to work now using Ubuntu 14.04.1 x64 live media and Radeon driver.
-- 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/1315834 Title: 1002:983d [Acer Aspire V5-122P] Unable to adjust screen brightness using Radeon driver Status in “linux” package in Ubuntu: Triaged Bug description: While using the Radeon driver, I am unable to adjust the screen brightness on my Acer Aspire V5-122P. Adjusting brightness in the settings applet has no affect. Adjusting brightness with the keyboard function keys turns the screen on and off seemingly randomly. WORKAROUND: sudo -s cd /sys/class/backlight/radeon_bl0 cat max_brightness echo 200 > brightness #Example echo 10 > brightness #Example echo 255 > brightness #Example Upstream post URL: http://www.spinics.net/lists/linux- acpi/msg50719.html ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: linux-image-3.13.0-24-generic 3.13.0-24.46 ProcVersionSignature: Ubuntu 3.13.0-24.46-generic 3.13.9 Uname: Linux 3.13.0-24-generic x86_64 ApportVersion: 2.14.1-0ubuntu3 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: lewis 2240 F.... pulseaudio /dev/snd/controlC0: lewis 2240 F.... pulseaudio CurrentDesktop: Unity Date: Sun May 4 10:55:50 2014 HibernationDevice: RESUME=UUID=42931b07-a2e1-49a1-9780-874e1d4300b7 InstallationDate: Installed on 2014-04-14 (19 days ago) InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Beta amd64 (20140326) MachineType: Acer Aspire V5-122P ProcFB: 0 radeondrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-24-generic.efi.signed root=UUID=8a594eb2-ccc3-4aa4-a4c5-e872f4033b04 ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-3.13.0-24-generic N/A linux-backports-modules-3.13.0-24-generic N/A linux-firmware 1.127 SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 07/18/2013 dmi.bios.vendor: Insyde Corp. dmi.bios.version: V2.08 dmi.board.asset.tag: Base Board Asset Tag dmi.board.name: Aspire V5-122P dmi.board.vendor: Acer dmi.board.version: V2.08 dmi.chassis.type: 10 dmi.chassis.vendor: Acer dmi.chassis.version: V2.08 dmi.modalias: dmi:bvnInsydeCorp.:bvrV2.08:bd07/18/2013:svnAcer:pnAspireV5-122P:pvrV2.08:rvnAcer:rnAspireV5-122P:rvrV2.08:cvnAcer:ct10:cvrV2.08: dmi.product.name: Aspire V5-122P dmi.product.version: V2.08 dmi.sys.vendor: Acer To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1315834/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
