net: bgmac: allocate struct bgmac just once & don't copy it

So far were were allocating struct bgmac in 3 places: platform code,
bcma code and shared bgmac_enet_probe function. The reason for this was
bgmac_enet_probe:
1) Requiring early-filled struct bgmac
2) Calling alloc_etherdev on its own in order to use netdev_priv later

This solution got few drawbacks:
1) Was duplicating allocating code
2) Required copying early-filled struct
3) Resulted in platform/bcma code having access only to unused struct

Solve this situation by simply extracting some probe code into the new
bgmac_alloc function.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/broadcom/bgmac.c b/drivers/net/ethernet/broadcom/bgmac.c
index 9122608..fe88126 100644
--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
@@ -1446,22 +1446,32 @@ int bgmac_phy_connect_direct(struct bgmac *bgmac)
 }
 EXPORT_SYMBOL_GPL(bgmac_phy_connect_direct);
 
-int bgmac_enet_probe(struct bgmac *info)
+struct bgmac *bgmac_alloc(struct device *dev)
 {
 	struct net_device *net_dev;
 	struct bgmac *bgmac;
-	int err;
 
 	/* Allocation and references */
-	net_dev = alloc_etherdev(sizeof(*bgmac));
+	net_dev = devm_alloc_etherdev(dev, sizeof(*bgmac));
 	if (!net_dev)
-		return -ENOMEM;
+		return NULL;
 
 	net_dev->netdev_ops = &bgmac_netdev_ops;
 	net_dev->ethtool_ops = &bgmac_ethtool_ops;
+
 	bgmac = netdev_priv(net_dev);
-	memcpy(bgmac, info, sizeof(*bgmac));
+	bgmac->dev = dev;
 	bgmac->net_dev = net_dev;
+
+	return bgmac;
+}
+EXPORT_SYMBOL_GPL(bgmac_alloc);
+
+int bgmac_enet_probe(struct bgmac *bgmac)
+{
+	struct net_device *net_dev = bgmac->net_dev;
+	int err;
+
 	net_dev->irq = bgmac->irq;
 	SET_NETDEV_DEV(net_dev, bgmac->dev);
 
@@ -1488,7 +1498,7 @@ int bgmac_enet_probe(struct bgmac *info)
 	err = bgmac_dma_alloc(bgmac);
 	if (err) {
 		dev_err(bgmac->dev, "Unable to alloc memory for DMA\n");
-		goto err_netdev_free;
+		goto err_out;
 	}
 
 	bgmac->int_mask = BGMAC_IS_ERRMASK | BGMAC_IS_RX | BGMAC_IS_TX_MASK;
@@ -1521,8 +1531,7 @@ int bgmac_enet_probe(struct bgmac *info)
 	phy_disconnect(net_dev->phydev);
 err_dma_free:
 	bgmac_dma_free(bgmac);
-err_netdev_free:
-	free_netdev(net_dev);
+err_out:
 
 	return err;
 }