Chargers for Zire
 

I have two Zire 31 and charge them either via a IPhone charger (using a different cord) or by an LG cell phone charger.

The USB mini plug charger is very slow (yeah you can charge when the computer is on via the USB) and I suppose no drivers required (but if you have a Palm desktop on the computer then the driver would logically be there.)

I am not sure about the Zire22 but the zire 21 sometimes has a slightly different power plug than the one on Zire 31.