Brightness controls are not working in Unity / Xorg. When pressing the keys <fn><home> and <fn><end> on my Lenovo W510, I see the indicator on the screen showing the level of brightness changing, so key mapping is not the problem. However, the brightness is not changing.
On the kernel level, I have the single following device:
# cd /sys/class/backlight
# ls -l
total 0
lrwxrwxrwx 1 root root 0 Nov 3 17:16 acpi_video0 -> ../../devices/pci0000:00/0000:00:03.0/0000:01:00.0/backlight/acpi_video0
When playing with the <fn><home> and <fn><end>, the value of /sys/class/backlight/brightness changes accordingly. The screen brightness does not change.
Performing:
# echo 10 >brightness
...does not have any effect (regardless of the value provided, 10 being just an example).
WORKAROUND
There is an odd workaround. Simply go to the console using <CTRL><ALT><F1> and using the <fn><home> and <fn><end> keys, brightness then changes. Return to Unity / Xorg with <CTRL><ALT><F7> and the selected brightness persists.
in xorg.conf might fix the problem. I do not have an xorg and when I let the proprietary Nvidia driver generate one and add this option, X does not start anymore.
Ubuntu 14.04.1 LTS with latest updates as of this writing.
Brightness controls are not working in Unity / Xorg. When pressing the keys <fn><home> and <fn><end> on my Lenovo W510, I see the indicator on the screen showing the level of brightness changing, so key mapping is not the problem. However, the brightness is not changing.
On the kernel level, I have the single following device:
# cd /sys/class/ backlight pci0000: 00/0000: 00:03.0/ 0000:01: 00.0/backlight/ acpi_video0
# ls -l
total 0
lrwxrwxrwx 1 root root 0 Nov 3 17:16 acpi_video0 -> ../../devices/
When playing with the <fn><home> and <fn><end>, the value of /sys/class/ backlight/ brightness changes accordingly. The screen brightness does not change.
Performing:
# echo 10 >brightness
...does not have any effect (regardless of the value provided, 10 being just an example).
WORKAROUND
There is an odd workaround. Simply go to the console using <CTRL><ALT><F1> and using the <fn><home> and <fn><end> keys, brightness then changes. Return to Unity / Xorg with <CTRL><ALT><F7> and the selected brightness persists.
NON WORKING WORKAROUND
On the web, I read that adding:
Option "RegistryDwords" "EnableBrightne ssControl= 1"'
in xorg.conf might fix the problem. I do not have an xorg and when I let the proprietary Nvidia driver generate one and add this option, X does not start anymore.
Ubuntu 14.04.1 LTS with latest updates as of this writing.
ProblemType: Bug ature: Ubuntu 3.13.0- 39.66-generic 3.13.11.8 dules: nvidia nvidia. gpus.0: Error: [Errno 21] Is a directory: '/proc/ driver/ nvidia/ gpus/0' nvidia. registry: Binary: "" nvidia. version: support. test.0:
DistroRelease: Ubuntu 14.04
Package: xorg 1:7.7+1ubuntu8
ProcVersionSign
Uname: Linux 3.13.0-39-generic x86_64
NonfreeKernelMo
.proc.driver.
.proc.driver.
.proc.driver.
NVRM version: NVIDIA UNIX x86_64 Kernel Module 331.38 Wed Jan 8 19:32:30 PST 2014
GCC version: gcc version 4.8.2 (Ubuntu 4.8.2-19ubuntu1)
.tmp.unity.
ApportVersion: 2.14.1-0ubuntu3.5 detection, composite, opengl, compiztoolbox, decor,place, put,snap, resize, move,regex, session, vpswitch, imgpng, gnomecompat, text,ring, grid,mousepoll, animation, unitymtgrabhand les,wall, expo,ezoom, workarounds, fade,scale, unityshell] irectDriverBlac klist: '(nouveau| Intel). *Mesa 8.0' irectFSW: true nterest: Yes /vmlinuz- 3.13.0- 39-generic root=UUID= 994f9c2c- f967-472e- ace3-23cd620ec7 02 ro quiet splash asset.tag: No Asset Information version: Not Available bvr6NET84WW( 1.45):bd10/ 03/2012: svnLENOVO: pn4318CTO: pvrThinkPadW510 :rvnLENOVO: rn4318CTO: rvrNotAvailable :cvnLENOVO: ct10:cvrNotAvai lable: version: ThinkPad W510 2+14.04. 20140714- 0ubuntu1 libgl1- mesa-dri: libgl1-mesa-dri 10.1.3-0ubuntu0.1 libgl1- mesa-dri- experimental: libgl1- mesa-dri- experimental N/A libgl1- mesa-glx: libgl1-mesa-glx 10.1.3-0ubuntu0.1 nvidia- graphics- drivers: nvidia- graphics- drivers N/A xserver- xorg-core: xserver-xorg-core 2:1.15.1-0ubuntu2.1 xserver- xorg-input- evdev: xserver- xorg-input- evdev 1:2.8.2-1ubuntu2 xserver- xorg-video- ati: xserver- xorg-video- ati 1:7.3.0-1ubuntu3.1 xserver- xorg-video- intel: xserver- xorg-video- intel 2:2.99. 910-0ubuntu1. 1 xserver- xorg-video- nouveau: xserver- xorg-video- nouveau 1:1.0.10-1ubuntu2
Architecture: amd64
CompizPlugins: [core,bailer,
CompositorRunning: compiz
CompositorUnred
CompositorUnred
CurrentDesktop: Unity
Date: Tue Nov 4 07:38:59 2014
DistUpgraded: Fresh install
DistroCodename: trusty
DistroVariant: ubuntu
DkmsStatus:
bbswitch, 0.7, 3.13.0-32-generic, x86_64: installed
bbswitch, 0.7, 3.13.0-39-generic, x86_64: installed
nvidia-331, 331.38, 3.13.0-32-generic, x86_64: installed
nvidia-331, 331.38, 3.13.0-39-generic, x86_64: installed
tp-smapi, 0.41, 3.13.0-32-generic, x86_64: installed
ExtraDebuggingI
GraphicsCard:
NVIDIA Corporation GT216GLM [Quadro FX 880M] [10de:0a3c] (rev a2) (prog-if 00 [VGA controller])
Subsystem: Lenovo Device [17aa:2145]
InstallationDate: Installed on 2014-11-01 (3 days ago)
InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
MachineType: LENOVO 4318CTO
ProcKernelCmdLine: BOOT_IMAGE=
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 10/03/2012
dmi.bios.vendor: LENOVO
dmi.bios.version: 6NET84WW (1.45 )
dmi.board.name: 4318CTO
dmi.board.vendor: LENOVO
dmi.board.version: Not Available
dmi.chassis.
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.
dmi.modalias: dmi:bvnLENOVO:
dmi.product.name: 4318CTO
dmi.product.
dmi.sys.vendor: LENOVO
version.compiz: compiz 1:0.9.11.
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.52-1
version.
version.
version.
version.
version.
version.
version.
version.
version.
xserver.bootTime: Tue Nov 4 01:40:35 2014
xserver.configfile: default
xserver.errors: open /dev/fb0: No such file or directory
xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:
xserver.version: 2:1.15.1-0ubuntu2.1