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I installed Ubuntu 14.04.02 as dual boot in a macbook pro 2012 13 I noticed that all function buttons works but except those that regulate the brightness of the screen.How do I fix this problem?

Mudit Kapil
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Riccardo
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  • Maybe related: http://askubuntu.com/questions/126441/brightness-controls-doesnt-work-on-a-macbook-pro-5-5-ubuntu-12-04-lts http://askubuntu.com/questions/370857/cant-adjust-screen-brightness-on-macbook-pro-10-1-ubuntu-13-10 – meskobalazs Feb 24 '15 at 13:57
  • My macbook has not nvidia graphic card, so probably nvidia drivers doesn't fix the problem in this case – Riccardo Feb 24 '15 at 14:10
  • BTW, can you change the brightness using the command line? – meskobalazs Feb 24 '15 at 14:24
  • I was reading this post [link]http://askubuntu.com/questions/57236/unable-to-change-brightness-in-a-lenovo-laptop/57610#57610[link]. When I run ls /sys/class/backlight/*/brightness, my output is /sys/class/backlight/apple_backlight/brightness. /sys/class/backlight/intel_backlight/brightness. Which one do I use? apple_backlight or intel_backlight? – Riccardo Feb 24 '15 at 14:35
  • Ok, I can change the brightness using command line but is there another method? – Riccardo Feb 24 '15 at 14:47
  • That was just a test, so we know, that only the control buttons are not working. – meskobalazs Feb 24 '15 at 14:51
  • Could you add the Xorg.conf file to the question? BTW check this out: http://itsfoss.com/fix-brightness-ubuntu-1310/ – meskobalazs Feb 24 '15 at 14:59

1 Answers1

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I found an answer to this. However I have an iMac 2011, so it could solve your problem.

You need to edit the grub file /etc/default/grub change the line

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

to

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor acpi_osi=Linux"

Then run:

sudo update-grub

Rebooot your computer and voilà.

David Foerster
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Beshari
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