diff --git a/drivers/usb/serial/airprime.c b/drivers/usb/serial/airprime.c
index 77bb893bf2e922c51bb51ef4e2ac69f6d2cd2a86..f156dba0300f77168f7774199e988074bd249e8a 100644
--- a/drivers/usb/serial/airprime.c
+++ b/drivers/usb/serial/airprime.c
@@ -217,7 +217,10 @@ static void airprime_close(struct usb_serial_port *port, struct file * filp)
 	priv->rts_state = 0;
 	priv->dtr_state = 0;
 
-	airprime_send_setup(port);
+	mutex_lock(&port->serial->disc_mutex);
+	if (!port->serial->disconnected)
+		airprime_send_setup(port);
+	mutex_lock(&port->serial->disc_mutex);
 
 	for (i = 0; i < NUM_READ_URBS; ++i) {
 		usb_kill_urb (priv->read_urbp[i]);
diff --git a/drivers/usb/serial/cp2101.c b/drivers/usb/serial/cp2101.c
index cd5f71b7f6372b251967c317f8829450e508c912..f3ca66017a031ba81db256216b905b4cf3989efa 100644
--- a/drivers/usb/serial/cp2101.c
+++ b/drivers/usb/serial/cp2101.c
@@ -348,7 +348,10 @@ static void cp2101_close (struct usb_serial_port *port, struct file * filp)
 	usb_kill_urb(port->write_urb);
 	usb_kill_urb(port->read_urb);
 
-	cp2101_set_config_single(port, CP2101_UART, UART_DISABLE);
+	mutex_lock(&port->serial->disc_mutex);
+	if (!port->serial->disconnected)
+		cp2101_set_config_single(port, CP2101_UART, UART_DISABLE);
+	mutex_unlock(&port->serial->disc_mutex);
 }
 
 /*
diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index 2c142bb04fe17256616de04d07891a4ad27fea5f..90dcc625f70deb008c45ca0c6c349ba0a6d6eb4e 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -1198,7 +1198,8 @@ static void ftdi_close (struct usb_serial_port *port, struct file *filp)
 
 	dbg("%s", __FUNCTION__);
 
-	if (c_cflag & HUPCL){
+	mutex_lock(&port->serial->disc_mutex);
+	if (c_cflag & HUPCL && !port->serial->disconnected){
 		/* Disable flow control */
 		if (usb_control_msg(port->serial->dev,
 				    usb_sndctrlpipe(port->serial->dev, 0),
@@ -1212,6 +1213,7 @@ static void ftdi_close (struct usb_serial_port *port, struct file *filp)
 		/* drop RTS and DTR */
 		clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
 	} /* Note change no line if hupcl is off */
+	mutex_unlock(&port->serial->disc_mutex);
 
 	/* cancel any scheduled reading */
 	cancel_delayed_work(&priv->rx_work);
diff --git a/drivers/usb/serial/garmin_gps.c b/drivers/usb/serial/garmin_gps.c
index f1c90cfe72515365236c9ddf61e1c41ee90fe82a..d74e43d69230b5ea1d7b75a4b599f9052f658004 100644
--- a/drivers/usb/serial/garmin_gps.c
+++ b/drivers/usb/serial/garmin_gps.c
@@ -1020,19 +1020,26 @@ static void garmin_close (struct usb_serial_port *port, struct file * filp)
 	if (!serial)
 		return;
 
-	garmin_clear(garmin_data_p);
+	mutex_lock(&port->serial->disc_mutex);
+	if (!port->serial->disconnected)
+		garmin_clear(garmin_data_p);
 
 	/* shutdown our urbs */
 	usb_kill_urb (port->read_urb);
 	usb_kill_urb (port->write_urb);
 
-	if (noResponseFromAppLayer(garmin_data_p) ||
-	    ((garmin_data_p->flags & CLEAR_HALT_REQUIRED) != 0)) {
-		process_resetdev_request(port);
-		garmin_data_p->state = STATE_RESET;
+	if (!port->serial->disconnected) {
+		if (noResponseFromAppLayer(garmin_data_p) ||
+		    ((garmin_data_p->flags & CLEAR_HALT_REQUIRED) != 0)) {
+			process_resetdev_request(port);
+			garmin_data_p->state = STATE_RESET;
+		} else {
+			garmin_data_p->state = STATE_DISCONNECTED;
+		}
 	} else {
 		garmin_data_p->state = STATE_DISCONNECTED;
 	}
+	mutex_unlock(&port->serial->disc_mutex);
 }
 
 
diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c
index c2347995c786e7224e18fb784bd2c4327ad7d610..22b3f78a388ce0d40486ede8c98f9af41051dc49 100644
--- a/drivers/usb/serial/visor.c
+++ b/drivers/usb/serial/visor.c
@@ -362,7 +362,7 @@ static void visor_close (struct usb_serial_port *port, struct file * filp)
 			kfree (transfer_buffer);
 		}
 	}
-	mutex_lock(&port->serial->disc_mutex);
+	mutex_unlock(&port->serial->disc_mutex);
 
 	if (stats)
 		dev_info(&port->dev, "Bytes In = %d  Bytes Out = %d\n",