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Neither the keyboard keys not the control panel fixes this issue. The only solution is to reboot, which is a pain. How do I fix this?


  • Toshiba Portege z935
  • Ubuntu 12.04
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I had the same issue with a Portege R935 in 12.04, and I'm dealing with it with this (not so elegant) workaround:

  • as root (not with sudo but actually changing user: su root), change the value in sys/class/backlight/intel_backlight/brightness

    for example:

    echo 2937 > /sys/class/backlight/intel_backlight/brightness

Warning: these brightness values aren't between 0 and 7 (as the ones in the other directory), but between 284 and 4539, or something like that.

Hope it helps.

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