struct cyclades_card *card;
        unsigned long flags;
 
-#ifdef CY_DEBUG_OTHER
-       printk(KERN_DEBUG "cyc:cy_close ttyC%d\n", info->line);
-#endif
-
        if (!info || serial_paranoia_check(info, tty->name, "cy_close"))
                return;
 
        card = info->card;
 
-       spin_lock_irqsave(&card->card_lock, flags);
-       /* If the TTY is being hung up, nothing to do */
-       if (tty_hung_up_p(filp)) {
-               spin_unlock_irqrestore(&card->card_lock, flags);
+       if (!tty_port_close_start(&info->port, tty, filp))
                return;
-       }
-#ifdef CY_DEBUG_OPEN
-       printk(KERN_DEBUG "cyc:cy_close ttyC%d, count = %d\n", info->line,
-               info->port.count);
-#endif
-       if ((tty->count == 1) && (info->port.count != 1)) {
-               /*
-                * Uh, oh.  tty->count is 1, which means that the tty
-                * structure will be freed.  Info->count should always
-                * be one in these conditions.  If it's greater than
-                * one, we've got real problems, since it means the
-                * serial port won't be shutdown.
-                */
-               printk(KERN_ERR "cyc:cy_close: bad serial port count; "
-                       "tty->count is 1, info->port.count is %d\n", info->port.count);
-               info->port.count = 1;
-       }
-#ifdef CY_DEBUG_COUNT
-       printk(KERN_DEBUG  "cyc:cy_close at (%d): decrementing count to %d\n",
-               current->pid, info->port.count - 1);
-#endif
-       if (--info->port.count < 0) {
-#ifdef CY_DEBUG_COUNT
-               printk(KERN_DEBUG "cyc:cyc_close setting count to 0\n");
-#endif
-               info->port.count = 0;
-       }
-       if (info->port.count) {
-               spin_unlock_irqrestore(&card->card_lock, flags);
-               return;
-       }
-       info->port.flags |= ASYNC_CLOSING;
-
-       /*
-        * Now we wait for the transmit buffer to clear; and we notify
-        * the line discipline to only process XON/XOFF characters.
-        */
-       tty->closing = 1;
-       spin_unlock_irqrestore(&card->card_lock, flags);
-       if (info->port.closing_wait != CY_CLOSING_WAIT_NONE)
-               tty_wait_until_sent(tty, info->port.closing_wait);
 
        spin_lock_irqsave(&card->card_lock, flags);
 
        spin_unlock_irqrestore(&card->card_lock, flags);
        cy_shutdown(info, tty);
        cy_flush_buffer(tty);
-       tty_ldisc_flush(tty);
-       spin_lock_irqsave(&card->card_lock, flags);
 
-       tty->closing = 0;
        tty_port_tty_set(&info->port, NULL);
-       if (info->port.blocked_open) {
-               spin_unlock_irqrestore(&card->card_lock, flags);
-               if (info->port.close_delay) {
-                       msleep_interruptible(jiffies_to_msecs
-                                               (info->port.close_delay));
-               }
-               wake_up_interruptible(&info->port.open_wait);
-               spin_lock_irqsave(&card->card_lock, flags);
-       }
-       info->port.flags &= ~(ASYNC_NORMAL_ACTIVE | ASYNC_CLOSING);
-       wake_up_interruptible(&info->port.close_wait);
 
-#ifdef CY_DEBUG_OTHER
-       printk(KERN_DEBUG "cyc:cy_close done\n");
-#endif
-
-       spin_unlock_irqrestore(&card->card_lock, flags);
+       tty_port_close_end(&info->port, tty);
 }                              /* cy_close */
 
 /* This routine gets called when tty_write has put something into