ref: 6a09d2da7e29f18a244f3a3a2959d0a78ed9540b dir: /sys/src/cmd/nusb/usbd/fns.h/
int attachdev(Port*); void detachdev(Port*); void work(void); Hub* newhub(char *, Dev*); void hname(char *); void checkidle(void);