Hey mate!
Well, he uses the fingers that are normally used in acoustics. Thumb, index, middle and ring (right hand) if you check the videos in you tube his pinky finger is most of the time resting on the body of the guitar or sometimes it moves but that's because is involuntary, not because he's using it.
And in the left hand he uses all four fingers (I've never seen him playing with his thumb but he might be using it when it's necessary).
I hope this will answer your question, if not please don't doubt to post asking me.
Cheers