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I have dual-booted my Macbook Pro with Ubuntu 12.04 . Whenever i log-in to Ubuntu, it does so with full screen brightness and keyboard backlight at full . How do i get rid of this? How can i tweak the start-up setting for screen brightness and disable keyboard backlight at start-up?

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see also… – naught101 Oct 12 '12 at 11:26

To fix the screen brightness on my Macbook I stopped the apple_bl kernel module from being loaded. This seem to fix this for me.

  1. Create a file called: /etc/modprobe.d/blacklist-applebl.conf
  2. In the above file add the line:

     blacklist apple_bl
  3. Reboot.

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I tried this, but it still reboots with maximum brightness. – hektor May 26 '12 at 15:34
OK i read the question wrong. My install also always starts at full brightnesss. But I usually use suspend. Can you control the brightness using the keys? – Tim May 29 '12 at 2:43
Yep i can use the keys to control the brightness. – hektor May 29 '12 at 13:02

On my 11.2 MacBook Pro running Ubuntu 13.10, I got satisfactory results with this command, which makes an upstart task to dim them upon starting the login screen:

sudo cat > /etc/init/mbp-save-battery.conf << EOF
description "Lower screen and keyboard backlight brightness on boot"


start on login-session-start

  # lower screen brightness
  echo "35" > /sys/class/backlight/acpi_video0/brightness

  # Somebody else turns on the keyboard backlight
  # Wait for them before turning it off.
  sleep 1
  echo "0" > /sys/class/leds/smc\:\:kbd_backlight/brightness
end script

The sleep for the keyboard backlight control is not ideal, but it has worked every time for me.

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I should note that the keyboard backlight occasionally turns itself back on. Not sure what causes that. – cgmb Jul 17 '14 at 4:48

Keyboard backlight is only partially implemented, I think. It's working for unity, but in KDE there's no UI for it. You can manually change the keyboard backlight brightness on the command line. I don't have a mac, so I'm not sure what the exact command is, but for my samsung, the command is

echo 5 > /sys/class/leds/samsung\:\:kbd_backlight/brightness

(you have to do this as root, you can use sudo -s)

For the mac, have a look in /sys/class/leds, and see what's there.

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Has been a long time that you asked this question. I had a similar problem and solved it this way:

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Welcome to Ask Ubuntu! Whilst this may theoretically answer the question, it would be preferable to include the essential parts of the answer here, and provide the link for reference. Also, please edit this post at least to include explicit disclosure that this is your blog. Our policy requires this when linking in answers to a site with which you are affiliated. – Eliah Kagan Jul 31 '12 at 0:08

I believe I can help you with the screen brightness. I've posted what worked from me as an answer to a similar question on Ask Ubuntu.

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