From 760db29bdc97b73ff60b091315ad787b1deb5cf5 Mon Sep 17 00:00:00 2001
From: Phil Elwell <phil@raspberrypi.org>
Date: Thu, 19 Apr 2018 17:59:38 +0100
Subject: [PATCH] lan78xx: Read MAC address from DT if present
Git-commit: 760db29bdc97b73ff60b091315ad787b1deb5cf5
Patch-mainline: v4.18-rc1
References: bsc#1085262

There is a standard mechanism for locating and using a MAC address from
the Device Tree. Use this facility in the lan78xx driver to support
applications without programmed EEPROM or OTP. At the same time,
regularise the handling of the different address sources.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/usb/lan78xx.c | 42 +++++++++++++++++++--------------------
 1 file changed, 20 insertions(+), 22 deletions(-)

diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 0867f7275852..a823f010de30 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -37,6 +37,7 @@
 #include <linux/irqchip/chained_irq.h>
 #include <linux/microchipphy.h>
 #include <linux/phy.h>
+#include <linux/of_net.h>
 #include "lan78xx.h"
 
 #define DRIVER_AUTHOR	"WOOJUNG HUH <woojung.huh@microchip.com>"
@@ -1652,34 +1653,31 @@ static void lan78xx_init_mac_address(struct lan78xx_net *dev)
 	addr[5] = (addr_hi >> 8) & 0xFF;
 
 	if (!is_valid_ether_addr(addr)) {
-		/* reading mac address from EEPROM or OTP */
-		if ((lan78xx_read_eeprom(dev, EEPROM_MAC_OFFSET, ETH_ALEN,
-					 addr) == 0) ||
-		    (lan78xx_read_otp(dev, EEPROM_MAC_OFFSET, ETH_ALEN,
-				      addr) == 0)) {
-			if (is_valid_ether_addr(addr)) {
-				/* eeprom values are valid so use them */
-				netif_dbg(dev, ifup, dev->net,
-					  "MAC address read from EEPROM");
-			} else {
-				/* generate random MAC */
-				random_ether_addr(addr);
-				netif_dbg(dev, ifup, dev->net,
-					  "MAC address set to random addr");
-			}
-
-			addr_lo = addr[0] | (addr[1] << 8) |
-				  (addr[2] << 16) | (addr[3] << 24);
-			addr_hi = addr[4] | (addr[5] << 8);
-
-			ret = lan78xx_write_reg(dev, RX_ADDRL, addr_lo);
-			ret = lan78xx_write_reg(dev, RX_ADDRH, addr_hi);
+		if (!eth_platform_get_mac_address(&dev->udev->dev, addr)) {
+			/* valid address present in Device Tree */
+			netif_dbg(dev, ifup, dev->net,
+				  "MAC address read from Device Tree");
+		} else if (((lan78xx_read_eeprom(dev, EEPROM_MAC_OFFSET,
+						 ETH_ALEN, addr) == 0) ||
+			    (lan78xx_read_otp(dev, EEPROM_MAC_OFFSET,
+					      ETH_ALEN, addr) == 0)) &&
+			   is_valid_ether_addr(addr)) {
+			/* eeprom values are valid so use them */
+			netif_dbg(dev, ifup, dev->net,
+				  "MAC address read from EEPROM");
 		} else {
 			/* generate random MAC */
 			random_ether_addr(addr);
 			netif_dbg(dev, ifup, dev->net,
 				  "MAC address set to random addr");
 		}
+
+		addr_lo = addr[0] | (addr[1] << 8) |
+			  (addr[2] << 16) | (addr[3] << 24);
+		addr_hi = addr[4] | (addr[5] << 8);
+
+		ret = lan78xx_write_reg(dev, RX_ADDRL, addr_lo);
+		ret = lan78xx_write_reg(dev, RX_ADDRH, addr_hi);
 	}
 
 	ret = lan78xx_write_reg(dev, MAF_LO(0), addr_lo);
-- 
2.18.0