diff --git a/drivers/usb/serial/mxuport.c b/drivers/usb/serial/mxuport.c
index 34142feffd4d..3aef091fe88b 100644
--- a/drivers/usb/serial/mxuport.c
+++ b/drivers/usb/serial/mxuport.c
@@ -951,6 +951,7 @@ static int mxuport_calc_num_ports(struct usb_serial *serial,
 {
 	unsigned long features = (unsigned long)usb_get_serial_data(serial);
 	int num_ports;
+	int i;
 
 	if (features & MX_UPORT_2_PORT) {
 		num_ports = 2;
@@ -966,6 +967,17 @@ static int mxuport_calc_num_ports(struct usb_serial *serial,
 		num_ports = 2;
 	}
 
+	/*
+	 * Setup bulk-out endpoint multiplexing. All ports share the same
+	 * bulk-out endpoint.
+	 */
+	BUILD_BUG_ON(ARRAY_SIZE(epds->bulk_out) < 16);
+
+	for (i = 1; i < num_ports; ++i)
+		epds->bulk_out[i] = epds->bulk_out[0];
+
+	epds->num_bulk_out = num_ports;
+
 	return num_ports;
 }
 
@@ -1149,102 +1161,11 @@ static int mxuport_port_probe(struct usb_serial_port *port)
 				     port->port_number);
 }
 
-static int mxuport_alloc_write_urb(struct usb_serial *serial,
-				   struct usb_serial_port *port,
-				   struct usb_serial_port *port0,
-				   int j)
-{
-	struct usb_device *dev = interface_to_usbdev(serial->interface);
-
-	set_bit(j, &port->write_urbs_free);
-	port->write_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
-	if (!port->write_urbs[j])
-		return -ENOMEM;
-
-	port->bulk_out_buffers[j] = kmalloc(port0->bulk_out_size, GFP_KERNEL);
-	if (!port->bulk_out_buffers[j])
-		return -ENOMEM;
-
-	usb_fill_bulk_urb(port->write_urbs[j], dev,
-			  usb_sndbulkpipe(dev, port->bulk_out_endpointAddress),
-			  port->bulk_out_buffers[j],
-			  port->bulk_out_size,
-			  serial->type->write_bulk_callback,
-			  port);
-	return 0;
-}
-
-
-static int mxuport_alloc_write_urbs(struct usb_serial *serial,
-				    struct usb_serial_port *port,
-				    struct usb_serial_port *port0)
-{
-	int j;
-	int ret;
-
-	for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
-		ret = mxuport_alloc_write_urb(serial, port, port0, j);
-		if (ret)
-			return ret;
-	}
-	return 0;
-}
-
-
 static int mxuport_attach(struct usb_serial *serial)
 {
 	struct usb_serial_port *port0 = serial->port[0];
 	struct usb_serial_port *port1 = serial->port[1];
-	struct usb_serial_port *port;
 	int err;
-	int i;
-	int j;
-
-	/*
-	 * Throw away all but the first allocated write URBs so we can
-	 * set them up again to fit the multiplexing scheme.
-	 */
-	for (i = 1; i < serial->num_bulk_out; ++i) {
-		port = serial->port[i];
-		for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
-			usb_free_urb(port->write_urbs[j]);
-			kfree(port->bulk_out_buffers[j]);
-			port->write_urbs[j] = NULL;
-			port->bulk_out_buffers[j] = NULL;
-		}
-		port->write_urbs_free = 0;
-	}
-
-	/*
-	 * All write data is sent over the first bulk out endpoint,
-	 * with an added header to indicate the port. Allocate URBs
-	 * for each port to the first bulk out endpoint.
-	 */
-	for (i = 1; i < serial->num_ports; ++i) {
-		port = serial->port[i];
-		port->bulk_out_size = port0->bulk_out_size;
-		port->bulk_out_endpointAddress =
-			port0->bulk_out_endpointAddress;
-
-		err = mxuport_alloc_write_urbs(serial, port, port0);
-		if (err)
-			return err;
-
-		port->write_urb = port->write_urbs[0];
-		port->bulk_out_buffer = port->bulk_out_buffers[0];
-
-		/*
-		 * Ensure each port has a fifo. The framework only
-		 * allocates a fifo to ports with a bulk out endpoint,
-		 * where as we need one for every port.
-		 */
-		if (!kfifo_initialized(&port->write_fifo)) {
-			err = kfifo_alloc(&port->write_fifo, PAGE_SIZE,
-					  GFP_KERNEL);
-			if (err)
-				return err;
-		}
-	}
 
 	/*
 	 * All data from the ports is received on the first bulk in