usb_sndbulkpipe(priv->udev, P54U_PIPE_DATA),
                          skb->data, skb->len, FREE_AFTER_TX(skb) ?
                          p54u_tx_cb : p54u_tx_dummy_cb, skb);
+       addr_urb->transfer_flags |= URB_ZERO_PACKET;
+       data_urb->transfer_flags |= URB_ZERO_PACKET;
 
        usb_anchor_urb(addr_urb, &priv->submitted);
        err = usb_submit_urb(addr_urb, GFP_ATOMIC);
                goto out;
        }
 
-       usb_anchor_urb(addr_urb, &priv->submitted);
+       usb_anchor_urb(data_urb, &priv->submitted);
        err = usb_submit_urb(data_urb, GFP_ATOMIC);
        if (err)
                usb_unanchor_urb(data_urb);
         * free what's inside the transfer_buffer after the callback routine
         * has completed.
         */
-       int_urb->transfer_flags |= URB_FREE_BUFFER;
+       int_urb->transfer_flags |= URB_FREE_BUFFER | URB_ZERO_PACKET;
 
        usb_fill_bulk_urb(data_urb, priv->udev,
                          usb_sndbulkpipe(priv->udev, P54U_PIPE_DATA),
                          hdr, skb->len + sizeof(*hdr), FREE_AFTER_TX(skb) ?
                          p54u_tx_cb : p54u_tx_dummy_cb, skb);
+       data_urb->transfer_flags |= URB_ZERO_PACKET;
 
        usb_anchor_urb(int_urb, &priv->submitted);
        err = usb_submit_urb(int_urb, GFP_ATOMIC);