Brightness randomly up and down on MSI laptop

Question

I am experiencing this issue on my MSI GS60. It starts happening as soon as I use an Fn Key for the first time while running Ubuntu (I have also tested the issue on Arch and it's even worse there).

Ubuntu seems to think there was a brightness up / down keypress randomly (Fn + Up arrow or Fn + Down arrow) even when I am not touching the laptop's keyboard. When I turn the laptop off it shows as if a key was pressed.

I would not mind not being able to use any Fn Key (even though it'd be preferable if they were enabled) as long as I can stop this brightness issue.

Solution

This seems to be a common problem on most MSI laptops, including my own GP62 6QF Leopard Pro. Supposedly, one way to fix it would be to update your BIOS, however, this didn't work for me.

I managed to fix this by adding this to /usr/share/X11/xorg.conf.d/10-quirks.conf:

  Section "InputClass"
  Identifier "Spooky Ghosts"
  MatchProduct "Video Bus"
  Option "Ignore" "on"
  EndSection

This basically ignores messages from the Video Bus, which seems to be sending psuedo fn+up fn+down messages randomly.

Source: https://ubuntuforums.org/showthread.php?t=2314161&page=2

EDIT: Note that this is not a permanent fix as 10-quirks.conf is a file frequently overwritten by OS updates. The most recent update at this time of writing, released on the 7th of August, had overwritten this file and the above-mentioned script was not retained. To fix it back again, you'll just have to type it back in again, or submit a bug report informing them about this fix.

FYI, the 10-quirks.conf file is used for exactly this cause -- to fix bugs caused by hardware incompatibilities.

Comments

[vagaerg]

That solved the issue. You're right in the 10-quirks.conf file being replaced frequently, but it's still better than having brightness going up and down. Thanks! :)

[ahmad]

Seeing as I'm unable to add a comment to euwbah's suggestion... Place this in /etc/X11/xorg.conf.d/10-quirks.conf, as opposed to under /usr/share, to prevent it ever being overwritten :)

[andrew]

Just for note: After config change you need to restart X Window Server

[dejoma]

This did not work for me AND it stopped me from using the FN brightness keys. After restart those keys did not work anymore and I had to change brightness via the settings.