ref: 9cf3dc9a259cadc80e6d3840c658ef1d5f7c94a4 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);