ref: 11bc8cce33b3922e0fbc4f2d63a42426f6f5a4db dir: /sys/src/cmd/nusb/usbd/fns.h/
int attachdev(Port*); void detachdev(Port*); void work(void); Hub* newhub(char *, Dev*); int hname(char *); void checkidle(void);