[MIPS] tc35815: Load MAC address via platform_device

TX49XX SoCs include PCI NIC (TC35815 compatible) connected via its
internal PCI bus, but the NIC's PROM interface is not connected to
SEEPROM.  So we must provide its ethernet address by another way.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

drivers/net/tc35815.c

@@ -23,9 +23,9 @@
  */
 
 #ifdef TC35815_NAPI
-#define DRV_VERSION	"1.35-NAPI"
+#define DRV_VERSION	"1.36-NAPI"
 #else
-#define DRV_VERSION	"1.35"
+#define DRV_VERSION	"1.36"
 #endif
 static const char *version = "tc35815.c:v" DRV_VERSION "\n";
 #define MODNAME			"tc35815"
@@ -49,6 +49,7 @@ static const char *version = "tc35815.c:v" DRV_VERSION "\n";
 #include <linux/pci.h>
 #include <linux/mii.h>
 #include <linux/ethtool.h>
+#include <linux/platform_device.h>
 #include <asm/io.h>
 #include <asm/byteorder.h>
 
@@ -597,13 +598,46 @@ static int tc_mdio_read(struct net_device *dev, int phy_id, int location);
 static void tc_mdio_write(struct net_device *dev, int phy_id, int location,
 			  int val);
 
-static void __devinit tc35815_init_dev_addr (struct net_device *dev)
+#ifdef CONFIG_CPU_TX49XX
+/*
+ * Find a platform_device providing a MAC address.  The platform code
+ * should provide a "tc35815-mac" device with a MAC address in its
+ * platform_data.
+ */
+static int __devinit tc35815_mac_match(struct device *dev, void *data)
+{
+	struct platform_device *plat_dev = to_platform_device(dev);
+	struct pci_dev *pci_dev = data;
+	unsigned int id = (pci_dev->bus->number << 8) | pci_dev->devfn;
+	return !strcmp(plat_dev->name, "tc35815-mac") && plat_dev->id == id;
+}
+
+static int __devinit tc35815_read_plat_dev_addr(struct net_device *dev)
+{
+	struct tc35815_local *lp = dev->priv;
+	struct device *pd = bus_find_device(&platform_bus_type, NULL,
+					    lp->pci_dev, tc35815_mac_match);
+	if (pd) {
+		if (pd->platform_data)
+			memcpy(dev->dev_addr, pd->platform_data, ETH_ALEN);
+		put_device(pd);
+		return is_valid_ether_addr(dev->dev_addr) ? 0 : -ENODEV;
+	}
+	return -ENODEV;
+}
+#else
+static int __devinit tc35815_read_plat_dev_addr(struct device *dev)
+{
+	return -ENODEV;
+}
+#endif
+
+static int __devinit tc35815_init_dev_addr (struct net_device *dev)
 {
 	struct tc35815_regs __iomem *tr =
 		(struct tc35815_regs __iomem *)dev->base_addr;
 	int i;
 
-	/* dev_addr will be overwritten on NETDEV_REGISTER event */
 	while (tc_readl(&tr->PROM_Ctl) & PROM_Busy)
 		;
 	for (i = 0; i < 6; i += 2) {
@@ -615,6 +649,9 @@ static void __devinit tc35815_init_dev_addr (struct net_device *dev)
 		dev->dev_addr[i] = data & 0xff;
 		dev->dev_addr[i+1] = data >> 8;
 	}
+	if (!is_valid_ether_addr(dev->dev_addr))
+		return tc35815_read_plat_dev_addr(dev);
+	return 0;
 }
 
 static int __devinit tc35815_init_one (struct pci_dev *pdev,
@@ -724,7 +761,10 @@ static int __devinit tc35815_init_one (struct pci_dev *pdev,
 	tc35815_chip_reset(dev);
 
 	/* Retrieve the ethernet address. */
-	tc35815_init_dev_addr(dev);
+	if (tc35815_init_dev_addr(dev)) {
+		dev_warn(&pdev->dev, "not valid ether addr\n");
+		random_ether_addr(dev->dev_addr);
+	}
 
 	rc = register_netdev (dev);
 	if (rc)