Brightness Controls work but brightness doesnt change

[Nisheet Lall]

I am unable to change the brigthness of the screen, the controls work properly but changing the brightness level has no impact on the screen brightness. It feels like the old intel brightness regression bug. The brightness is always at the full level.

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: xorg 1:7.7+1ubuntu5
ProcVersionSignature: Ubuntu 3.10.0-5.15-generic 3.10.2
Uname: Linux 3.10.0-5-generic x86_64
ApportVersion: 2.11-0ubuntu1
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
Date: Fri Aug 2 00:35:28 2013
DistUpgraded: Fresh install
DistroCodename: saucy
DistroVariant: ubuntu
DkmsStatus:
 bbswitch, 0.7, 3.10.0-3-generic, x86_64: installed
 bbswitch, 0.7, 3.10.0-4-generic, x86_64: installed
 bbswitch, 0.7, 3.10.0-5-generic, x86_64: installed
 nvidia-304, 304.88, 3.10.0-4-generic, x86_64: installed
 nvidia-304, 304.88, 3.10.0-5-generic, x86_64: installed
DpkgLog:

ExtraDebuggingInterest: Yes, if not too technical
GraphicsCard:
 Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0116] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: Lenovo Device [17aa:397d]
 NVIDIA Corporation GF108M [GeForce GT 520M] [10de:0df7] (rev ff) (prog-if ff)
InstallationDate: Installed on 2013-06-02 (60 days ago)
InstallationMedia: Ubuntu-GNOME 13.10 "Saucy Salamander" - Alpha amd64 (20130601)
MachineType: LENOVO HuronRiver Platform
MarkForUpload: True
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.10.0-5-generic root=UUID=f80879ea-b397-4778-bb59-f9fb5c8fa4ce ro quiet splash vt.handoff=7
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 10/21/2011
dmi.bios.vendor: LENOVO
dmi.bios.version: 45CN38WW
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: Emerald Lake
dmi.board.vendor: LENOVO
dmi.board.version: FAB1
dmi.chassis.asset.tag: Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: 0.1
dmi.modalias: dmi:bvnLENOVO:bvr45CN38WW:bd10/21/2011:svnLENOVO:pnHuronRiverPlatform:pvrIdeapadZ570:rvnLENOVO:rnEmeraldLake:rvrFAB1:cvnLENOVO:ct10:cvr0.1:
dmi.product.name: HuronRiver Platform
dmi.product.version: Ideapad Z570
dmi.sys.vendor: LENOVO
version.compiz: compiz N/A
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.45-2ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 9.1.4-0ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 9.1.4-0ubuntu3
version.xserver-xorg-core: xserver-xorg-core 2:1.14.2-0ubuntu1
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.3-0ubuntu3.1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.1.0-0ubuntu2.1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.21.9-0ubuntu3
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.8-0ubuntu1.1
xserver.bootTime: Thu Aug 1 22:15:43 2013
xserver.configfile: default
xserver.errors:

xserver.logfile: /var/log/Xorg.0.log
xserver.version: 2:1.14.2-0ubuntu1
xserver.video_driver: intel

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Andrea Biolo (andrewbiolo89)]

Hi! Have you also installed mir/xmir?

[Sukarn Singh Maini (sukarn)]

I am facing this bug on 13.10 with an intel graphics card and nVidia Optimus chip. Brightness controls were fine before upgrading from 13.04

[Sukarn Singh Maini (sukarn)]

Update -

# ls /sys/class/backlight has three listings
acpi_video0 acpi_video1 intel_backlight

# cat /sys/class/backlight/intel_backlight/max_brightness
976

# echo 100 > /sys/class/backlight/intel_backlight/brightness
bash: /sys/class/backlight/intel_backlight/brightness: Permission denied

# sudo -s

root# echo 100 > /sys/class/backlight/intel_backlight/brightness

This last command worked and my brightness was changed successfully. I tried other values too, and they all seem to work. I didn't try going beyond the max_brightness value, of course.

Is there something else I could try that would help in narrowing down and / or fixing this bug?

[Nisheet Lall (nisheet-lall)]

Hi Sukarn,

I tried and its working perfectly fine, are the controls broken. I suspect the control might not be calling the intel_brightness command. <Its a noob statement but just a guess>

[blaamann (baggetun)]

I am affected by this too after upgrading to 13.10. It worked fine in 12.10 and 13.04.

Using function keys I get an OSD showing brightness level increasing/decreasing, but screen brightness does not change.

This is on an Lenovo laptop running upgradet 13.10 with Intel Graphics using i915.

Setting brightness with 'echo 350 > /sys/class/backlight/intel_backlight/brightness' does work for me.

[penalvch (penalvch)]

Nisheet Lall, this bug was reported a while ago and there hasn't been any activity in it recently. We were wondering if this is still an issue? If so, could you please test for this with the latest development release of Ubuntu? ISO images are available from http://cdimage.ubuntu.com/daily-live/current/ .

If it remains an issue, could you please run the following command in the development release from a Terminal (Applications->Accessories->Terminal), as it will automatically gather and attach updated debug information to this report:

apport-collect -p linux REPLACE-WITH-BUG-NUMBER

If reproducible, could you also please test the latest upstream kernel available (not the daily folder) following https://wiki.ubuntu.com/KernelMainlineBuilds ? It will allow additional upstream developers to examine the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this bug is fixed in the mainline kernel, please add the following tags:
kernel-fixed-upstream
kernel-fixed-upstream-VERSION-NUMBER

where VERSION-NUMBER is the version number of the kernel you tested. For example:
kernel-fixed-upstream-v3.13-rc7

This can be done by clicking on the yellow circle with a black pencil icon next to the word Tags located at the bottom of the bug description. As well, please remove the tag:
needs-upstream-testing

If the mainline kernel does not fix this bug, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-VERSION-NUMBER

As well, please remove the tag:
needs-upstream-testing

Once testing of the upstream kernel is complete, please mark this bug's Status as Confirmed. Please let us know your results. Thank you for your understanding.

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]

[Yanpas (yanpaso)]

This bug is still in trusty

[penalvch (penalvch)]

Yanpas, thank you for your comment. So your hardware and problem may be tracked, could you please file a new report with Ubuntu 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.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[Yanpas (yanpaso)]

Christopher, I have always found a workaround, is there still need to boot at another kernel? (Also how to save error report to a file?)
My netbook - Asus eeepc 1018p

The WORKAROUND:
http://itsfoss.com/fix-brightness-ubuntu-1310/

pen a terminal and create the following configuration file, if it does not exist:

touch /usr/share/X11/xorg.conf.d/20-intel.conf
Now we need to edit this file. You can use any editor be it a terminal one or graphical.

sudo gedit /usr/share/X11/xorg.conf.d/20-intel.conf
Add the following lines to this file:

Section "Device"
        Identifier "card0"
        Driver "intel"
        Option "Backlight" "intel_backlight"
        BusID "PCI:0:2:0"

EndSection
Save it. Log out and log in back. The brightness control should be working through function keys now.