phylib: allow incremental scanning of an mii bus

This patch splits the bus scanning code in mdiobus_register() off
into a separate function, and makes this function available for
calling from external code.  This allows incrementally scanning an
mii bus, e.g. as information about which addresses are 'safe' to
scan becomes available.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Andy Fleming <afleming@freescale.com>
diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index 94e0b7e..e7508c1 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -60,49 +60,14 @@
 		bus->reset(bus);
 
 	for (i = 0; i < PHY_MAX_ADDR; i++) {
-		struct phy_device *phydev;
+		bus->phy_map[i] = NULL;
+		if ((bus->phy_mask & (1 << i)) == 0) {
+			struct phy_device *phydev;
 
-		if (bus->phy_mask & (1 << i)) {
-			bus->phy_map[i] = NULL;
-			continue;
+			phydev = mdiobus_scan(bus, i);
+			if (IS_ERR(phydev))
+				err = PTR_ERR(phydev);
 		}
-
-		phydev = get_phy_device(bus, i);
-
-		if (IS_ERR(phydev))
-			return PTR_ERR(phydev);
-
-		/* There's a PHY at this address
-		 * We need to set:
-		 * 1) IRQ
-		 * 2) bus_id
-		 * 3) parent
-		 * 4) bus
-		 * 5) mii_bus
-		 * And, we need to register it */
-		if (phydev) {
-			phydev->irq = bus->irq[i];
-
-			phydev->dev.parent = bus->dev;
-			phydev->dev.bus = &mdio_bus_type;
-			snprintf(phydev->dev.bus_id, BUS_ID_SIZE, PHY_ID_FMT, bus->id, i);
-
-			phydev->bus = bus;
-
-			/* Run all of the fixups for this PHY */
-			phy_scan_fixups(phydev);
-
-			err = device_register(&phydev->dev);
-
-			if (err) {
-				printk(KERN_ERR "phy %d failed to register\n",
-						i);
-				phy_device_free(phydev);
-				phydev = NULL;
-			}
-		}
-
-		bus->phy_map[i] = phydev;
 	}
 
 	pr_info("%s: probed\n", bus->name);
@@ -122,6 +87,48 @@
 }
 EXPORT_SYMBOL(mdiobus_unregister);
 
+struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
+{
+	struct phy_device *phydev;
+	int err;
+
+	phydev = get_phy_device(bus, addr);
+	if (IS_ERR(phydev) || phydev == NULL)
+		return phydev;
+
+	/* There's a PHY at this address
+	 * We need to set:
+	 * 1) IRQ
+	 * 2) bus_id
+	 * 3) parent
+	 * 4) bus
+	 * 5) mii_bus
+	 * And, we need to register it */
+
+	phydev->irq = bus->irq != NULL ? bus->irq[addr] : PHY_POLL;
+
+	phydev->dev.parent = bus->dev;
+	phydev->dev.bus = &mdio_bus_type;
+	snprintf(phydev->dev.bus_id, BUS_ID_SIZE, PHY_ID_FMT, bus->id, addr);
+
+	phydev->bus = bus;
+
+	/* Run all of the fixups for this PHY */
+	phy_scan_fixups(phydev);
+
+	err = device_register(&phydev->dev);
+	if (err) {
+		printk(KERN_ERR "phy %d failed to register\n", addr);
+		phy_device_free(phydev);
+		phydev = NULL;
+	}
+
+	bus->phy_map[addr] = phydev;
+
+	return phydev;
+}
+EXPORT_SYMBOL(mdiobus_scan);
+
 /**
  * mdio_bus_match - determine if given PHY driver supports the given PHY device
  * @dev: target PHY device