kernel-packages team mailing list archive

["Christopher M. Penalver" <christopher.m.penalver@xxxxxxxxx>]

Johan Bernhardsson, if you have a bug in Ubuntu, the Ubuntu Kernel team, Ubuntu Bug Control team, and Ubuntu Bug Squad would like you to please file a new report by executing the following in a terminal while booted into a Ubuntu repository kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Please note, not filing a new report would delay your problem being
addressed as quickly as possible.

No need exists to comment here at this time. After reading the above
documention in it's entirety, if you have further questions, you are
welcome to redirect them to the appropriate mailing list or forum via
http://www.ubuntu.com/support/community/mailinglists , or you may
contact me directly.

Thank you for your understanding.

-- 
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/1205694

Title:
  Taichi 21 external screen is not working properly (probably due
  backlight)

Status in “linux” package in Ubuntu:
  Incomplete

Bug description:
  First of all, I'd like to say that both screen are recognized by xrandr: The internal as eDP1 and the external as DP1. 
  The external screen works under some circumstances, but without backlight. 

  If the computer is off, and I turn on with the lid closed, the external screen "works" 
  If the computer is turned on, on linux, and I restart, the external screen keeps "working".

  If the computer is off and I turn on with the lid opened or the
  computer is on windows, using the external screen, and I restart to
  linux, I can't use the external screen: The image keeps "off".
  Although, the screen is recognized by xrandr, but no setting turns the
  screen on (not even xrandr --output DP1 --auto)

  In the situations that the external screen works, the backlight has no effect on it: 
  When I adjust the backlight (either by the hotkeys, or by echo 50 > /sys/class/backlight/acpi_video0/brightness, or echo 3000 > /sys/class/backlight/intel_backlight/brightness), it just adjusts the internal screen
  When I use the hotkey to turn off the screen, it just turn off the internal screen

  Also, if I use xrandr to turn off the external screen, or suspend the
  computer, the external screen is turned off. When I try again to turn
  on, or resume it doesn't work.

  I tried to boot with acpi_backlight=vendor, and again just the internal screen worked properly. The hotkey to change the backlight didn't work, but  echo 3000 > /sys/class/backlight/intel_backlight/brightness worked
  I tried to boot with video.use_bios_initial_backlight=0 and the backlight worked just for the internal screen again
  I tried to boot with acpi_osi="!Windows 2012", the same thing

  By running dmesg | grep 'ACPI: Video', I get:
  [    4.981826] ACPI: Video Device [GFX0] (multi-head: yes  rom: no  post: no)

  And lspci |  grep VGA shows:
  00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)

  I don't know if I should get 2 results in them, since I have two
  screens, but in DSDT, I just see one device with methods _DOS, _DOD,
  so I guess it is right.  There is an if in the BCL, checking if it is
  Windows 8, but I believe acpi_osi="!Windows 2012", should "fix" it if
  that was the problem

  I believe that solving the backlight problem when I'm able to turn on
  the screen might solve the screen not turning on with the lid open.

  I tried to use the current Mainline kernel (3.11.0-999, or something
  like that), but after the boot the external screen was off and the
  internal was on, not showing anything but a black screen.

  I followed the Kernel/Debugging/Backlight page and I'll submit all the
  files that it generated.

  Thank you for your help!

  ProblemType: Bug
  DistroRelease: Ubuntu 13.04
  Package: linux-image-3.8.0-26-generic 3.8.0-26.38
  ProcVersionSignature: Ubuntu 3.8.0-26.38-generic 3.8.13.2
  Uname: Linux 3.8.0-26-generic x86_64
  ApportVersion: 2.9.2-0ubuntu8.1
  Architecture: amd64
  AudioDevicesInUse:
   USER        PID ACCESS COMMAND
   /dev/snd/controlC0:  joao       2437 F.... pulseaudio
  Date: Sat Jul 27 12:44:02 2013
  HibernationDevice: RESUME=UUID=8c6201ab-045c-4bb7-b20d-c4650cca8821
  InstallationDate: Installed on 2013-07-23 (4 days ago)
  InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
  MachineType: ASUSTeK COMPUTER INC. TAICHI21
  MarkForUpload: True
  ProcEnviron:
   TERM=xterm
   PATH=(custom, no user)
   XDG_RUNTIME_DIR=<set>
   LANG=en_US.UTF-8
   SHELL=/bin/bash
  ProcFB: 0 inteldrmfb
  ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.8.0-26-generic root=UUID=1b4e19b1-47cc-4068-a6d6-b73868b3c9d8 ro quiet splash vt.handoff=7
  RelatedPackageVersions:
   linux-restricted-modules-3.8.0-26-generic N/A
   linux-backports-modules-3.8.0-26-generic  N/A
   linux-firmware                            1.106
  SourcePackage: linux
  UpgradeStatus: No upgrade log present (probably fresh install)
  dmi.bios.date: 01/08/2013
  dmi.bios.vendor: American Megatrends Inc.
  dmi.bios.version: TAICHI21.208
  dmi.board.asset.tag: ATN12345678901234567
  dmi.board.name: TAICHI21
  dmi.board.vendor: ASUSTeK COMPUTER INC.
  dmi.board.version: 1.0
  dmi.chassis.asset.tag: No Asset Tag
  dmi.chassis.type: 10
  dmi.chassis.vendor: ASUSTeK COMPUTER INC.
  dmi.chassis.version: 1.0
  dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrTAICHI21.208:bd01/08/2013:svnASUSTeKCOMPUTERINC.:pnTAICHI21:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnTAICHI21:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0:
  dmi.product.name: TAICHI21
  dmi.product.version: 1.0
  dmi.sys.vendor: ASUSTeK COMPUTER INC.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1205694/+subscriptions