[PATCH] phy address mask support for generic phy layer

Adds a phy_mask field to struct mii_bus and uses it.  This field
indicates each phy address to be ignored when probing the mdio bus.

This support is needed for the fs_enet and ibm_emac drivers to be
converted to the generic phy layer among other drivers. Many systems
lock up on probing certain phy addresses or probing doesn't return
0xffff when nothing is found at the address. A new driver I'm
working on also makes use of this mask.

Signed-off-by: Matt Porter <mporter@kernel.crashing.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

drivers/net/phy/mdio_bus.c

@@ -61,6 +61,9 @@ int mdiobus_register(struct mii_bus *bus)
 	for (i = 0; i < PHY_MAX_ADDR; i++) {
 		struct phy_device *phydev;
 
+		if (bus->phy_mask & (1 << i))
+			continue;
+
 		phydev = get_phy_device(bus, i);
 
 		if (IS_ERR(phydev))

include/linux/phy.h

@@ -72,6 +72,9 @@ struct mii_bus {
 	/* list of all PHYs on bus */
 	struct phy_device *phy_map[PHY_MAX_ADDR];
 
+	/* Phy addresses to be ignored when probing */
+	u32 phy_mask;
+
 	/* Pointer to an array of interrupts, each PHY's
 	 * interrupt at the index matching its address */
 	int *irq;