Charging USB devices from a powered USB hub?

Hi, I have just bought a "Targus Desktop USB 2.0 4-Port Hub w/Audio Pass-Through" ( http://www.targus.com/us/productdetail.aspx?sku=ach80us ) powered USB hub. I also have a number of portable devices I usually charge from my PC or notebook via USB cable: Sony NWZ-S545 mp3 player, Amazon Kindle 3 ebook reader, an old Mio C220 satnav, a Nikon still camera etc. My question is wheter or not I can SAFELY charge these devices from the USB hub itself. I mean, I power up the HUB but do not turn on my computer, just attach these devices to the hub. Will they charge? Won't they overcharge? Should I connect them to the normal USB sockets of the hub or the "hi power" ports? Thanks