ref: 6ad06b36b2a61ce20cb6a6e4c5fd15ec8ac142f8 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);