I'm looking for a USB hub solution for small host computer (like a Raspberry Pi or Nexus tablet) that can simultaneously power/charge said host computer.
I've heard about the USB power delivery specification, but I can't find USB hubs that implement this.
I've also seen the Android Open Accessory Protocol. I don't think it's possible to program an Android Accessory to appear as a USB hub to the Android device, but feel free to prove me wrong.
Since I can't find any existing implementations, I'm going to implement it myself, on a PCB. Is there any specialized circuity involved in wiring a microcontroller (as a USB HUB) that provides Power Delivery?
Alternatively, I'd take a PIC/Arduino project that implements a USB Hub with power delivery, as a starting point.
Edit: pertains to Power Delivery circuitry.