sky2: fix suspend/resume races

There are a couple of possible races on suspend/resume.
First the driver needs to block new packets from being queued for Tx.
The other less likely problem is the watchdog timer going off
during resume.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/net/sky2.c

@@ -4329,10 +4329,14 @@ static int sky2_suspend(struct pci_dev *pdev, pm_message_t state)
 	if (!hw)
 		return 0;
 
+	del_timer_sync(&hw->watchdog_timer);
+	cancel_work_sync(&hw->restart_work);
+
 	for (i = 0; i < hw->ports; i++) {
 		struct net_device *dev = hw->dev[i];
 		struct sky2_port *sky2 = netdev_priv(dev);
 
+		netif_device_detach(dev);
 		if (netif_running(dev))
 			sky2_down(dev);
 
@@ -4383,6 +4387,8 @@ static int sky2_resume(struct pci_dev *pdev)
 
 	for (i = 0; i < hw->ports; i++) {
 		struct net_device *dev = hw->dev[i];
+
+		netif_device_attach(dev);
 		if (netif_running(dev)) {
 			err = sky2_up(dev);
 			if (err) {