ref: 4e9f39a3ec0712542af0d035c79b3bf0eb2f2cd3 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);