ref: 2c9f4c21ad0b5e66f06a3613f6e21d5fe9f0da6a 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);