iPad charging

I don't see why not. What's the output (current) rating of the USB port? It would be something like "1 A" or "2100 mA".

Now whether or not you'll get a net positive charge (while actively using it) is another matter. I've charged with a 5W (1A) iPhone cube power adapter and the charge percentage went down. However, I've never had it fail to get to 100% charge as long as I stopped using my iPads and left it to charge for a long enough time.

If it's just a 5v standard USB connection, it likely won't put out enough power to adequately charge an iPad. Simplest thing to I would guess is plug it in and see if your iPad charges