net: bcmgenet: disable clock before register_netdev

As soon as register_netdev() is called, the network device notifiers are
running which means that other parts of the kernel, or user-space
programs can call the network device ndo_open() callback and use the
interface.

Disable the Ethernet device clock before we register the network device
such that we do not create the following situation:

CPU0				CPU1
register_netdev()
				bcmgenet_open()
				clk_prepare_enable()
clk_disable_unprepare()

and leave the hardware block gated off, while we think it should be
gated on.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index 5ba1cfb..d17953c 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -2535,14 +2535,14 @@
 	netif_set_real_num_tx_queues(priv->dev, priv->hw_params->tx_queues + 1);
 	netif_set_real_num_rx_queues(priv->dev, priv->hw_params->rx_queues + 1);
 
-	err = register_netdev(dev);
-	if (err)
-		goto err_clk_disable;
-
 	/* Turn off the main clock, WOL clock is handled separately */
 	if (!IS_ERR(priv->clk))
 		clk_disable_unprepare(priv->clk);
 
+	err = register_netdev(dev);
+	if (err)
+		goto err;
+
 	return err;
 
 err_clk_disable: