ref: 3462ec9bdc97d2e56a193bb8ed6cb4a01a8e4ef8 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);