Brightness control not working

[atirut-w]

Hardware:

The slider itself works, but it doesn't do anything.

[ryonakano]

@hanaral Are you possibly reproducible this issue when you're facing the logged-out issue reported in elementary/triage#727? I saw this issue when that issue happens for me.

[hanaral]

@ryonakano I think so? I would assume it would stop anything that requires sudo access since you aren't technically 'logged in' with your user (your user has the sudo perms necessary to r/w brightness, mount drives etc.)

[jeremypw]

I can reproduce this by going into System Settings and switching "Automatically adjust brightness" on. As expected this disables the manual adjustment. However, switching the "Automatically adjust brightness" setting off did not re-enable the manual controls. Logging out and back in fixed it.

As an aside, when the manual controls are disabled they should not be shown.