*
* This routine is called synchronously when a particular tty device
* is closed for the last time freeing up the resources.
+ * Note that tty_shutdown() is not called if ops->shutdown is defined.
+ * This means one is responsible to take care of calling ops->remove (e.g.
+ * via tty_driver_remove_tty) and releasing tty->termios.
*
*
* void (*cleanup)(struct tty_struct * tty);