ref: 4fedd7d4fe1c3b509c84d12e971aaa466b8b4b3d 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);