Merge branch 'davinci_emac-read-the-MAC-address-from-nvmem'

Bartosz Golaszewski says:

====================
davinci_emac: read the MAC address from nvmem

This series is part of a bigger series that aims at removing the platform
data structure from the at24 EEPROM driver[1].

We provide a generalized version of of_get_nvmem_mac_address(), switch the
only user of the of_ variant to using it, remove the previous
implementation and use the new routine in the davinci_emac driver.

[1] https://lkml.org/lkml/2018/11/13/884
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/cadence/macb_main.c

@@ -4055,7 +4055,7 @@ static int macb_probe(struct platform_device *pdev)
 	if (mac) {
 		ether_addr_copy(bp->dev->dev_addr, mac);
 	} else {
-		err = of_get_nvmem_mac_address(np, bp->dev->dev_addr);
+		err = nvmem_get_mac_address(&pdev->dev, bp->dev->dev_addr);
 		if (err) {
 			if (err == -EPROBE_DEFER)
 				goto err_out_free_netdev;

drivers/net/ethernet/ti/davinci_emac.c

@@ -1912,11 +1912,15 @@ static int davinci_emac_probe(struct platform_device *pdev)
 		ether_addr_copy(ndev->dev_addr, priv->mac_addr);
 
 	if (!is_valid_ether_addr(priv->mac_addr)) {
-		/* Use random MAC if none passed */
-		eth_hw_addr_random(ndev);
-		memcpy(priv->mac_addr, ndev->dev_addr, ndev->addr_len);
-		dev_warn(&pdev->dev, "using random MAC addr: %pM\n",
-							priv->mac_addr);
+		/* Try nvmem if MAC wasn't passed over pdata or DT. */
+		rc = nvmem_get_mac_address(&pdev->dev, priv->mac_addr);
+		if (rc) {
+			/* Use random MAC if still none obtained. */
+			eth_hw_addr_random(ndev);
+			memcpy(priv->mac_addr, ndev->dev_addr, ndev->addr_len);
+			dev_warn(&pdev->dev, "using random MAC addr: %pM\n",
+				 priv->mac_addr);
+		}
 	}
 
 	ndev->netdev_ops = &emac_netdev_ops;

drivers/of/of_net.c

@@ -81,42 +81,3 @@ const void *of_get_mac_address(struct device_node *np)
 	return of_get_mac_addr(np, "address");
 }
 EXPORT_SYMBOL(of_get_mac_address);
-
-/**
- * Obtain the MAC address from an nvmem provider named 'mac-address' through
- * device tree.
- * On success, copies the new address into memory pointed to by addr and
- * returns 0. Returns a negative error code otherwise.
- * @np:		Device tree node containing the nvmem-cells phandle
- * @addr:	Pointer to receive the MAC address using ether_addr_copy()
- */
-int of_get_nvmem_mac_address(struct device_node *np, void *addr)
-{
-	struct nvmem_cell *cell;
-	const void *mac;
-	size_t len;
-	int ret;
-
-	cell = of_nvmem_cell_get(np, "mac-address");
-	if (IS_ERR(cell))
-		return PTR_ERR(cell);
-
-	mac = nvmem_cell_read(cell, &len);
-
-	nvmem_cell_put(cell);
-
-	if (IS_ERR(mac))
-		return PTR_ERR(mac);
-
-	if (len < ETH_ALEN || !is_valid_ether_addr(mac)) {
-		ret = -EINVAL;
-	} else {
-		ether_addr_copy(addr, mac);
-		ret = 0;
-	}
-
-	kfree(mac);
-
-	return ret;
-}
-EXPORT_SYMBOL(of_get_nvmem_mac_address);

include/linux/etherdevice.h

@@ -32,6 +32,7 @@
 struct device;
 int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr);
 unsigned char *arch_get_platform_mac_address(void);
+int nvmem_get_mac_address(struct device *dev, void *addrbuf);
 u32 eth_get_headlen(void *data, unsigned int max_len);
 __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev);
 extern const struct header_ops eth_header_ops;

include/linux/of_net.h

@@ -13,7 +13,6 @@
 struct net_device;
 extern int of_get_phy_mode(struct device_node *np);
 extern const void *of_get_mac_address(struct device_node *np);
-extern int of_get_nvmem_mac_address(struct device_node *np, void *addr);
 extern struct net_device *of_find_net_device_by_node(struct device_node *np);
 #else
 static inline int of_get_phy_mode(struct device_node *np)
@@ -26,11 +25,6 @@ static inline const void *of_get_mac_address(struct device_node *np)
 	return NULL;
 }
 
-static inline int of_get_nvmem_mac_address(struct device_node *np, void *addr)
-{
-	return -ENODEV;
-}
-
 static inline struct net_device *of_find_net_device_by_node(struct device_node *np)
 {
 	return NULL;

net/ethernet/eth.c

@@ -47,6 +47,7 @@
 #include <linux/inet.h>
 #include <linux/ip.h>
 #include <linux/netdevice.h>
+#include <linux/nvmem-consumer.h>
 #include <linux/etherdevice.h>
 #include <linux/skbuff.h>
 #include <linux/errno.h>
@@ -550,3 +551,40 @@ int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr)
 	return 0;
 }
 EXPORT_SYMBOL(eth_platform_get_mac_address);
+
+/**
+ * Obtain the MAC address from an nvmem cell named 'mac-address' associated
+ * with given device.
+ *
+ * @dev:	Device with which the mac-address cell is associated.
+ * @addrbuf:	Buffer to which the MAC address will be copied on success.
+ *
+ * Returns 0 on success or a negative error number on failure.
+ */
+int nvmem_get_mac_address(struct device *dev, void *addrbuf)
+{
+	struct nvmem_cell *cell;
+	const void *mac;
+	size_t len;
+
+	cell = nvmem_cell_get(dev, "mac-address");
+	if (IS_ERR(cell))
+		return PTR_ERR(cell);
+
+	mac = nvmem_cell_read(cell, &len);
+	nvmem_cell_put(cell);
+
+	if (IS_ERR(mac))
+		return PTR_ERR(mac);
+
+	if (len != ETH_ALEN || !is_valid_ether_addr(mac)) {
+		kfree(mac);
+		return -EINVAL;
+	}
+
+	ether_addr_copy(addrbuf, mac);
+	kfree(mac);
+
+	return 0;
+}
+EXPORT_SYMBOL(nvmem_get_mac_address);