diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index 484b6a3c9b03714a3eae559e061f3767cdc3af72..d996038eacfd3d43ca3583ff69d02a8736601ff9 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -1084,6 +1084,10 @@ static void mxser_close(struct tty_struct *tty, struct file *filp)
 	mutex_lock(&port->mutex);
 	mxser_close_port(port);
 	mxser_flush_buffer(tty);
+	if (test_bit(ASYNCB_INITIALIZED, &port->flags)) {
+		if (C_HUPCL(tty))
+			tty_port_lower_dtr_rts(port);
+	}
 	mxser_shutdown_port(port);
 	clear_bit(ASYNCB_INITIALIZED, &port->flags);
 	mutex_unlock(&port->mutex);
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 74d9a0258d7c2126c3e34a2781e8ecf03c7281d3..642239015b46bbe9e18844f186a31296a343d5f9 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -2964,6 +2964,10 @@ static void gsmtty_close(struct tty_struct *tty, struct file *filp)
 	if (tty_port_close_start(&dlci->port, tty, filp) == 0)
 		goto out;
 	gsm_dlci_begin_close(dlci);
+	if (test_bit(ASYNCB_INITIALIZED, &dlci->port.flags)) {
+		if (C_HUPCL(tty))
+			tty_port_lower_dtr_rts(&dlci->port);
+	}
 	tty_port_close_end(&dlci->port, tty);
 	tty_port_tty_set(&dlci->port, NULL);
 out:
diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
index 7e3eaf4eb9fea923972e94f26493a60cbb8e3a12..0af8d9aa5b0231e179bdb448f02c296a03b6af55 100644
--- a/drivers/tty/tty_port.c
+++ b/drivers/tty/tty_port.c
@@ -196,13 +196,20 @@ void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty)
 }
 EXPORT_SYMBOL(tty_port_tty_set);
 
-static void tty_port_shutdown(struct tty_port *port)
+static void tty_port_shutdown(struct tty_port *port, struct tty_struct *tty)
 {
 	mutex_lock(&port->mutex);
 	if (port->console)
 		goto out;
 
 	if (test_and_clear_bit(ASYNCB_INITIALIZED, &port->flags)) {
+		/*
+		 * Drop DTR/RTS if HUPCL is set. This causes any attached
+		 * modem to hang up the line.
+		 */
+		if (tty && C_HUPCL(tty))
+			tty_port_lower_dtr_rts(port);
+
 		if (port->ops->shutdown)
 			port->ops->shutdown(port);
 	}
@@ -220,18 +227,19 @@ out:
 
 void tty_port_hangup(struct tty_port *port)
 {
+	struct tty_struct *tty;
 	unsigned long flags;
 
 	spin_lock_irqsave(&port->lock, flags);
 	port->count = 0;
 	port->flags &= ~ASYNC_NORMAL_ACTIVE;
-	if (port->tty) {
-		set_bit(TTY_IO_ERROR, &port->tty->flags);
-		tty_kref_put(port->tty);
-	}
+	tty = port->tty;
+	if (tty)
+		set_bit(TTY_IO_ERROR, &tty->flags);
 	port->tty = NULL;
 	spin_unlock_irqrestore(&port->lock, flags);
-	tty_port_shutdown(port);
+	tty_port_shutdown(port, tty);
+	tty_kref_put(tty);
 	wake_up_interruptible(&port->open_wait);
 	wake_up_interruptible(&port->delta_msr_wait);
 }
@@ -485,11 +493,6 @@ int tty_port_close_start(struct tty_port *port,
 	/* Flush the ldisc buffering */
 	tty_ldisc_flush(tty);
 
-	/* Drop DTR/RTS if HUPCL is set. This causes any attached modem to
-	   hang up the line */
-	if (tty->termios.c_cflag & HUPCL)
-		tty_port_lower_dtr_rts(port);
-
 	/* Don't call port->drop for the last reference. Callers will want
 	   to drop the last active reference in ->shutdown() or the tty
 	   shutdown path */
@@ -524,7 +527,7 @@ void tty_port_close(struct tty_port *port, struct tty_struct *tty,
 {
 	if (tty_port_close_start(port, tty, filp) == 0)
 		return;
-	tty_port_shutdown(port);
+	tty_port_shutdown(port, tty);
 	set_bit(TTY_IO_ERROR, &tty->flags);
 	tty_port_close_end(port, tty);
 	tty_port_tty_set(port, NULL);