net: ethernet: bgmac: Allow MAC address to be specified in DTB

Allows the BCMA version of the bgmac driver to obtain MAC address
from the device tree.  If no MAC address is specified there, then
the previous behavior (obtaining MAC address from SPROM) is
used.
Signed-off-by: Steve Lin <steven.lin1@broadcom.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Jon Mason <jon.mason@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bgmac-bcma.c

@@ -11,6 +11,7 @@
 #include <linux/bcma/bcma.h>
 #include <linux/brcmphy.h>
 #include <linux/etherdevice.h>
+#include <linux/of_net.h>
 #include "bgmac.h"
 
 static inline bool bgmac_is_bcm4707_family(struct bcma_device *core)
@@ -114,7 +115,7 @@ static int bgmac_probe(struct bcma_device *core)
 	struct ssb_sprom *sprom = &core->bus->sprom;
 	struct mii_bus *mii_bus;
 	struct bgmac *bgmac;
-	u8 *mac;
+	const u8 *mac = NULL;
 	int err;
 
 	bgmac = bgmac_alloc(&core->dev);
@@ -127,21 +128,27 @@ static int bgmac_probe(struct bcma_device *core)
 
 	bcma_set_drvdata(core, bgmac);
 
-	switch (core->core_unit) {
-	case 0:
-		mac = sprom->et0mac;
-		break;
-	case 1:
-		mac = sprom->et1mac;
-		break;
-	case 2:
-		mac = sprom->et2mac;
-		break;
-	default:
-		dev_err(bgmac->dev, "Unsupported core_unit %d\n",
-			core->core_unit);
-		err = -ENOTSUPP;
-		goto err;
+	if (bgmac->dev->of_node)
+		mac = of_get_mac_address(bgmac->dev->of_node);
+
+	/* If no MAC address assigned via device tree, check SPROM */
+	if (!mac) {
+		switch (core->core_unit) {
+		case 0:
+			mac = sprom->et0mac;
+			break;
+		case 1:
+			mac = sprom->et1mac;
+			break;
+		case 2:
+			mac = sprom->et2mac;
+			break;
+		default:
+			dev_err(bgmac->dev, "Unsupported core_unit %d\n",
+				core->core_unit);
+			err = -ENOTSUPP;
+			goto err;
+		}
 	}
 
 	ether_addr_copy(bgmac->net_dev->dev_addr, mac);