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[Bug 1402365] Re: Backlight Bug

To: kernel-packages@xxxxxxxxxxxxxxxxxxx
From: "Christopher M. Penalver" <christopher.m.penalver@xxxxxxxxx>
Date: Sat, 27 Dec 2014 13:57:33 -0000
Reply-to: Bug 1402365 <1402365@xxxxxxxxxxxxxxxxxx>
Sender: bounces@xxxxxxxxxxxxx
Kamalakar Agashe, thank you for reporting this and helping make Ubuntu better. As per http://support.lenovo.com/us/en/products/laptops-and-netbooks/lenovo-g-series-laptops/g50-45-notebook-lenovo an update to your computer's buggy and outdated BIOS is available (A2CN26WW). If you update to this following https://help.ubuntu.com/community/BIOSUpdate does it change anything?  If it doesn't, could you please both specify what happened, and provide the output of the following terminal command:
sudo dmidecode -s bios-version && sudo dmidecode -s bios-release-date

For more on BIOS updates and linux, please see
https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette
.

Please note your current BIOS is already in the Bug Description, so
posting this on the old BIOS would not be helpful. As well, you don't
have to create a new bug report.

Once the BIOS is updated, then please mark this report Status Confirmed.

Thank you for your understanding.

** Description changed:

  Backlight control does not work, but there are entries in
  /sys/class/backlight.
  
  ls /sys/class/backlight > backlight
  grep -r . /proc/acpi > acpi
  sudo acpidump -o acpidump.txt
  acpixtract acpidump.txt
  iasl -d DSDT.dat
  sudo fwts > fwts
  sudo fwts method > fwts_method
  dmesg | grep 'ACPI: Video' > video
  sudo dmidecode > dmidecode.log
  cat /proc/version > version
  
  Testing for a work around
  Reboot with only the kernel parameter acpi_backlight=vendor
  does not work
  ls /sys/class/backlight > vendorbacklight
  
  No such folder /sys/class/backlight/intel_backlight/
  
  Reboot with just kernel parameter video.use_bios_initial_backlight=0
  does not work
  
- reboot with just kernel parameter video.use_native_backlight=1 
+ reboot with just kernel parameter video.use_native_backlight=1
  does not work
+ 
+ WORKAROUND: Install fglrx.
  
  ProblemType: Bug
  DistroRelease: Ubuntu 14.04
  Package: linux-image-3.13.0-43-generic 3.13.0-43.72
  ProcVersionSignature: Ubuntu 3.13.0-43.72-generic 3.13.11.11
  Uname: Linux 3.13.0-43-generic x86_64
  ApportVersion: 2.14.1-0ubuntu3.6
  Architecture: amd64
  AudioDevicesInUse:
-  USER        PID ACCESS COMMAND
-  /dev/snd/controlC1:  vidya      1832 F.... pulseaudio
-  /dev/snd/controlC0:  vidya      1832 F.... pulseaudio
+  USER        PID ACCESS COMMAND
+  /dev/snd/controlC1:  vidya      1832 F.... pulseaudio
+  /dev/snd/controlC0:  vidya      1832 F.... pulseaudio
  CurrentDesktop: Unity
  Date: Sun Dec 14 16:16:27 2014
  HibernationDevice: RESUME=UUID=42b35770-926b-43cf-8874-b5452e26b5e5
  InstallationDate: Installed on 2014-12-13 (0 days ago)
  InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
  MachineType: LENOVO 80E3
  ProcFB: 0 EFI VGA
  ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-43-generic.efi.signed root=UUID=7eccd389-f558-421b-928a-541b3f1c16f0 ro quiet splash vt.handoff=7 video.use_native_backlight=1
  RelatedPackageVersions:
-  linux-restricted-modules-3.13.0-43-generic N/A
-  linux-backports-modules-3.13.0-43-generic  N/A
-  linux-firmware                             1.127.10
+  linux-restricted-modules-3.13.0-43-generic N/A
+  linux-backports-modules-3.13.0-43-generic  N/A
+  linux-firmware                             1.127.10
  SourcePackage: linux
  UpgradeStatus: No upgrade log present (probably fresh install)
  dmi.bios.date: 08/26/2014
  dmi.bios.vendor: LENOVO
  dmi.bios.version: A2CN25WW(V1.07)
  dmi.board.asset.tag: No Asset Tag
  dmi.board.name: Lancer 5B2
  dmi.board.vendor: LENOVO
  dmi.board.version: SDK0F82990 WIN
  dmi.chassis.asset.tag: No Asset Tag
  dmi.chassis.type: 10
  dmi.chassis.vendor: LENOVO
  dmi.chassis.version: Lenovo G50-45
  dmi.modalias: dmi:bvnLENOVO:bvrA2CN25WW(V1.07):bd08/26/2014:svnLENOVO:pn80E3:pvrLenovoG50-45:rvnLENOVO:rnLancer5B2:rvrSDK0F82990WIN:cvnLENOVO:ct10:cvrLenovoG50-45:
  dmi.product.name: 80E3
  dmi.product.version: Lenovo G50-45
  dmi.sys.vendor: LENOVO

** Changed in: linux (Ubuntu)
   Importance: Medium => Low

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

-- 
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/1402365

Title:
  Backlight Bug

Status in linux package in Ubuntu:
  Incomplete

Bug description:
  Backlight control does not work, but there are entries in
  /sys/class/backlight.

  ls /sys/class/backlight > backlight
  grep -r . /proc/acpi > acpi
  sudo acpidump -o acpidump.txt
  acpixtract acpidump.txt
  iasl -d DSDT.dat
  sudo fwts > fwts
  sudo fwts method > fwts_method
  dmesg | grep 'ACPI: Video' > video
  sudo dmidecode > dmidecode.log
  cat /proc/version > version

  Testing for a work around
  Reboot with only the kernel parameter acpi_backlight=vendor
  does not work
  ls /sys/class/backlight > vendorbacklight

  No such folder /sys/class/backlight/intel_backlight/

  Reboot with just kernel parameter video.use_bios_initial_backlight=0
  does not work

  reboot with just kernel parameter video.use_native_backlight=1
  does not work

  WORKAROUND: Install fglrx.

  ProblemType: Bug
  DistroRelease: Ubuntu 14.04
  Package: linux-image-3.13.0-43-generic 3.13.0-43.72
  ProcVersionSignature: Ubuntu 3.13.0-43.72-generic 3.13.11.11
  Uname: Linux 3.13.0-43-generic x86_64
  ApportVersion: 2.14.1-0ubuntu3.6
  Architecture: amd64
  AudioDevicesInUse:
   USER        PID ACCESS COMMAND
   /dev/snd/controlC1:  vidya      1832 F.... pulseaudio
   /dev/snd/controlC0:  vidya      1832 F.... pulseaudio
  CurrentDesktop: Unity
  Date: Sun Dec 14 16:16:27 2014
  HibernationDevice: RESUME=UUID=42b35770-926b-43cf-8874-b5452e26b5e5
  InstallationDate: Installed on 2014-12-13 (0 days ago)
  InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
  MachineType: LENOVO 80E3
  ProcFB: 0 EFI VGA
  ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-43-generic.efi.signed root=UUID=7eccd389-f558-421b-928a-541b3f1c16f0 ro quiet splash vt.handoff=7 video.use_native_backlight=1
  RelatedPackageVersions:
   linux-restricted-modules-3.13.0-43-generic N/A
   linux-backports-modules-3.13.0-43-generic  N/A
   linux-firmware                             1.127.10
  SourcePackage: linux
  UpgradeStatus: No upgrade log present (probably fresh install)
  dmi.bios.date: 08/26/2014
  dmi.bios.vendor: LENOVO
  dmi.bios.version: A2CN25WW(V1.07)
  dmi.board.asset.tag: No Asset Tag
  dmi.board.name: Lancer 5B2
  dmi.board.vendor: LENOVO
  dmi.board.version: SDK0F82990 WIN
  dmi.chassis.asset.tag: No Asset Tag
  dmi.chassis.type: 10
  dmi.chassis.vendor: LENOVO
  dmi.chassis.version: Lenovo G50-45
  dmi.modalias: dmi:bvnLENOVO:bvrA2CN25WW(V1.07):bd08/26/2014:svnLENOVO:pn80E3:pvrLenovoG50-45:rvnLENOVO:rnLancer5B2:rvrSDK0F82990WIN:cvnLENOVO:ct10:cvrLenovoG50-45:
  dmi.product.name: 80E3
  dmi.product.version: Lenovo G50-45
  dmi.sys.vendor: LENOVO

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References

[Bug 1402365] [NEW] Backlight Bug
From: Kamalakar Agashe, 2014-12-14