EP_W0_CONFIG_CTRL
ep_w0_config = bus_space_read_2(iot, ioh, EP_W0_CONFIG_CTRL);
bus_space_write_2(iot, ioh, EP_W0_CONFIG_CTRL, 0);
bus_space_write_2(iot, ioh, EP_W0_CONFIG_CTRL, ENABLE_DRQ_IRQ);