The CDC ACM driver uses the tty layer correctly so needs conversion. Start by
adding and initializing the port structures.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 
 #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
        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) {
 
        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 */