Motorcycle brake adjustments?

I recently took my 2002 Sportster 1200 to the shop to have the front brake adjusted. There was a lot of free play in the hand lever. As I suspected there was a problem with one of the caliper pistons sticking thus allowing the free play in the hand lever. It was a minor problem and they fixed it pretty quickly. The problem is now that the pads are rubbing on the rotor slightly, which I imagine can't be good. Aren't the breaks supposed to be self adjusting? Is there an easy fix that I can do, or is it back to the shop?