ref: 5e5d37eff2a10fbb2b2e4e509703f533d17966e1 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);