URE_USB_FW_CTRL
reg = ure_read_2(sc, URE_USB_FW_CTRL, URE_MCU_TYPE_USB);
ure_write_2(sc, URE_USB_FW_CTRL, URE_MCU_TYPE_USB, reg);
URE_SETBIT_2(sc, URE_USB_FW_CTRL, URE_MCU_TYPE_USB, URE_AUTO_SPEEDUP);
reg = ure_read_2(sc, URE_USB_FW_CTRL, URE_MCU_TYPE_USB);
ure_write_2(sc, URE_USB_FW_CTRL, URE_MCU_TYPE_USB, reg);