diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 7a1164dd1d37..41d4ca527f82 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -89,6 +89,9 @@ static DEFINE_MUTEX(open_mutex);
 
 #define ACM_READY(acm)	(acm && acm->dev && acm->used)
 
+static const struct tty_port_operations acm_port_ops = {
+};
+
 #ifdef VERBOSE_DEBUG
 #define verbose	1
 #else
@@ -1082,6 +1085,8 @@ skip_normal_probe:
 	spin_lock_init(&acm->read_lock);
 	mutex_init(&acm->mutex);
 	acm->rx_endpoint = usb_rcvbulkpipe(usb_dev, epread->bEndpointAddress);
+	tty_port_init(&acm->port);
+	acm->port.ops = &acm_port_ops;
 
 	buf = usb_buffer_alloc(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma);
 	if (!buf) {
diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h
index 1f95e7aa1b66..19967cdb2691 100644
--- a/drivers/usb/class/cdc-acm.h
+++ b/drivers/usb/class/cdc-acm.h
@@ -90,7 +90,8 @@ struct acm {
 	struct usb_interface *control;			/* control interface */
 	struct usb_interface *data;			/* data interface */
 	struct tty_struct *tty;				/* the corresponding tty */
-	struct urb *ctrlurb;			/* urbs */
+	struct tty_port port;			 	/* our tty port data */
+	struct urb *ctrlurb;				/* urbs */
 	u8 *ctrl_buffer;				/* buffers of urbs */
 	dma_addr_t ctrl_dma;				/* dma handles of buffers */
 	u8 *country_codes;				/* country codes from device */