Visor problems

[chevyky]

This is probably a very simple fix, but wanted to run it by you guys before I attack it.

My interior drivers side covered visor is falling down on me when i drive. The problem is at night, the thing doesnt want to stay up and i would rather it go up or down on demand rather than always down.

Is there a screw I turn to tighten it, or is this something i will need to replace all together?

Its a standard visor, appears to be the original or an original repro.

Thanks