Man page 9 : parport_wait_event

parport_wait_event - wait for an event on a parallel port

int parport_wait_event(struct parport *  port , signed long  timeout );

port
    port to wait on

timeout
    time to wait (in jiffies)

This function waits for up to timeout jiffies for an interrupt to occur on a parallel port. If the port timeout is set to zero, it returns immediately.

If an interrupt occurs before the timeout period elapses, this function returns zero immediately. If it times out, it returns one. An error code less than zero indicates an error (most likely a pending signal), and the calling code should finish what itAqs doing as soon as it can.