Before performing the reverse bisect process I thought to ask directly in the linux-acpi mailing list which was the patch (or the set of patches) that have fixed the acpi/backlight issue .
This is the answer: (original message http://marc.info/?l=linux-acpi&m=140429106012604&w=2) -------------------------------- "I think you will need at least: commit fbc9fe1b4f222a7c575e3bd8e9defe59c6190a04 Author: Aaron Lu <aaron...@intel.com> Date: Fri Oct 11 21:27:45 2013 +0800 ACPI / video: Do not register backlight if win8 and native interface exists commit 0e9f81d3b7cd0649a3bc437391b6a0650f98f844 Author: Aaron Lu <aaron...@intel.com> Date: Tue Feb 18 13:54:20 2014 +0800 ACPI / video: Add systems that should favour native backlight interface commit 751109aad5834375ca9ed0dcfcd85a00cbf872b5 Author: Rafael J. Wysocki <rafael.j.wyso...@intel.com> Date: Thu Jun 5 22:47:35 2014 +0200 ACPI / video: Change the default for video.use_native_backlight to 1 Maybe others, you will need to figure them out." -------------------------------- I hope this will be helpful. Also, the first good working kernel is v3.16rc1. As long as I understand, instead of using a blacklist they have changed the default setup for the machines that are supporting Windows 8 with intel drivers. It seems that most of them don't use acpi. (More details starting from here http://lists.freedesktop.org/archives/intel- gfx/2013-October/034212.html) -- 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/1318299 Title: [Fujitsu Lifebook A512] Brightness hot keys Fn+F6/Fn+F7 don't work Status in “linux” package in Ubuntu: Triaged Bug description: Pressing Fn+F6 or Fn+F7 the brightness doesn't change. Upstream URL: http://marc.info/?l=linux- acpi&m=140178030214298&w=2 WORKAROUND: Execute at a terminal: for i in /sys/class/backlight/*; do echo $i;cat $i/brightness;cat $i/max_brightness;done shows this output: /sys/class/backlight/acpi_video0 1 100 /sys/class/backlight/intel_backlight 4882 4882 Create /usr/share/X11/xorg.conf.d/20-intel.conf to set the "intel_backlight" interface, which will make the brightness shortcuts Fn+F6 and Fn+F7 work: Section "Device" Identifier "card0" Driver "intel" Option "Backlight" "intel_backlight" BusID "PCI:0:2:0" EndSection ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: linux-image-3.13.0-24-generic 3.13.0-24.47 ProcVersionSignature: Ubuntu 3.13.0-24.47-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/controlC0: pinguinux 1731 F.... pulseaudio CurrentDesktop: Unity Date: Sun May 11 10:21:22 2014 HibernationDevice: RESUME=UUID=f6e9afa5-5b2f-4c3d-af00-aff1122b6fe6 InstallationDate: Installed on 2014-04-18 (22 days ago) InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417) MachineType: FUJITSU LIFEBOOK A512 ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-24-generic.efi.signed root=UUID=1cd50414-50f8-4f1c-9133-e7f3375c0415 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: 10/23/2013 dmi.bios.vendor: FUJITSU // Phoenix Technologies Ltd. dmi.bios.version: Version 1.16 dmi.board.name: FJNBB29 dmi.board.vendor: FUJITSU dmi.chassis.type: 10 dmi.chassis.vendor: FUJITSU dmi.modalias: dmi:bvnFUJITSU//PhoenixTechnologiesLtd.:bvrVersion1.16:bd10/23/2013:svnFUJITSU:pnLIFEBOOKA512:pvr:rvnFUJITSU:rnFJNBB29:rvr:cvnFUJITSU:ct10:cvr: dmi.product.name: LIFEBOOK A512 dmi.sys.vendor: FUJITSU To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1318299/+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
