ref: cb3f6ebad0a54a603fd1a7405e599764fd9c02e5
dir: /sys/src/cmd/nusb/usbd/fns.h/
void attachdev(Dev*); void detachdev(Dev*); void work(void); Hub* newhub(char *, Dev*); int hname(char *); void assignhname(Dev *dev); void checkidle(void); int portfeature(Hub*, int, int, int);