+ list_add_tail(&req->list, &dev->tx_reqs);
+
+ if (dev->port_usb->multi_pkt_xfer) {
+ dev->no_tx_req_used--;
+ req->length = 0;
+ in = dev->port_usb->in_ep;
+
+ if (!list_empty(&dev->tx_reqs)) {
+ new_req = container_of(dev->tx_reqs.next,
+ struct usb_request, list);
+ list_del(&new_req->list);
+ spin_unlock(&dev->req_lock);
+ if (new_req->length > 0) {
+ length = new_req->length;
+
+ /* NCM requires no zlp if transfer is
+ * dwNtbInMaxSize */
+ if (dev->port_usb->is_fixed &&
+ length == dev->port_usb->fixed_in_len &&
+ (length % in->maxpacket) == 0)
+ new_req->zero = 0;
+ else
+ new_req->zero = 1;
+
+ /* use zlp framing on tx for strict CDC-Ether
+ * conformance, though any robust network rx
+ * path ignores extra padding. and some hardware
+ * doesn't like to write zlps.
+ */
+ if (new_req->zero && !dev->zlp &&
+ (length % in->maxpacket) == 0) {
+ new_req->zero = 0;
+ length++;
+ }
+
+ new_req->length = length;
+ retval = usb_ep_queue(in, new_req, GFP_ATOMIC);
+ switch (retval) {
+ default:
+ DBG(dev, "tx queue err %d\n", retval);
+ break;
+ case 0:
+ spin_lock(&dev->req_lock);
+ dev->no_tx_req_used++;
+ spin_unlock(&dev->req_lock);
+ net->trans_start = jiffies;
+ }
+ } else {
+ spin_lock(&dev->req_lock);
+ list_add(&new_req->list, &dev->tx_reqs);
+ spin_unlock(&dev->req_lock);
+ }
+ } else {
+ spin_unlock(&dev->req_lock);
+ }
+ } else {
+ spin_unlock(&dev->req_lock);
+ dev_kfree_skb_any(skb);
+ }