ref: 522f08e5f1a4f16a2cb2016c7b03f86b1eadea30 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);