This patch set updates the usrp to support libusb-1.0. Asynchronous I/O through libusb is added with fusb_libusb1.*, which is heavily based on fusb_linux.*. In short, URB's and ioctl calls are replaced with libusb_transfer structs and native calls. Transfer reaping is handled by libusb and associated callbacks. I get 32Mb/s on all of my machines using test_usrp_standard_rx or tx. Due to the API rewrite in 1.0 from 0.12, there are alot of changes, many are simply name changes.
Transmit and receive both work, but not at same time (e.g. usrp_benchmark_usb.py). libusb does not create any internal threads, so for a single session fusb_libusb1 works in the same manner as fusb_linux with the callback called at controlled times. With multiple libusb sessions the callback may occur at any time and threading issues come into play causing behavior to become undefined. The use of separate libusb_contexts _might_ solve this issue; I have not had the time to look into it.