Did you find anything? I am looking for same.
Looks like the way is to use usb gadget API but can not find any good examples anywhere
What about you?
schneidz, can you please explain how libmtp/libusb is related to the TARGET?
The question is how to implement MTP on the device (Responder) but not how to make Linux box support MTP (Initiator).
If libmtp/libusb has nothing with MTP Responder please stop confuse ppl.