emaclite: enable transmit and receive time stamping.

This patch enables software (and phy device) time stamping. Since this
MAC uses phylib, adding the hooks make hardware time stamping in the phy
possible.

Compile tested only.

Cc: John Linn <john.linn@xilinx.com>
Signed-off-by: NRichard Cochran <richard.cochran@omicron.at>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/xilinx_emaclite.c

@@ -648,7 +648,8 @@ static void xemaclite_rx_handler(struct net_device *dev)
 	dev->stats.rx_packets++;
 	dev->stats.rx_bytes += len;
 
-	netif_rx(skb);		/* Send the packet upstream */
+	if (!skb_defer_rx_timestamp(skb))
+		netif_rx(skb);	/* Send the packet upstream */
 }
 
 /**
@@ -1030,15 +1031,19 @@ static int xemaclite_send(struct sk_buff *orig_skb, struct net_device *dev)
 	spin_lock_irqsave(&lp->reset_lock, flags);
 	if (xemaclite_send_data(lp, (u8 *) new_skb->data, len) != 0) {
 		/* If the Emaclite Tx buffer is busy, stop the Tx queue and
-		 * defer the skb for transmission at a later point when the
+		 * defer the skb for transmission during the ISR, after the
 		 * current transmission is complete */
 		netif_stop_queue(dev);
 		lp->deferred_skb = new_skb;
+		/* Take the time stamp now, since we can't do this in an ISR. */
+		skb_tx_timestamp(new_skb);
 		spin_unlock_irqrestore(&lp->reset_lock, flags);
 		return 0;
 	}
 	spin_unlock_irqrestore(&lp->reset_lock, flags);
 
+	skb_tx_timestamp(new_skb);
+
 	dev->stats.tx_bytes += len;
 	dev_kfree_skb(new_skb);