ref: 2eadf1fa1703e5da4a98ba9c1a2bdc23bd140d8c 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);