NET: Support clause 45 MDIO commands at the MDIO bus level

IEEE 802.3ae clause 45 specifies a somewhat modified MDIO protocol
for use by 10GIGE phys. The main change is a 21 bit address split into
a 5 bit device ID and a 16 bit register offset. The definition is designed
so that normal and extended devices can run on the same MDIO bus.

Extend mdio-bitbang to do the new protocol. At the MDIO bus level the
protocol is requested by or'ing MII_ADDR_C45 into the register offset.

Make phy_read/phy_write/etc pass a full 32 bit register offset.

This does not attempt to make the phy layer support C45 style PHYs, just
to provide the MDIO bus support.

Tested against a Broadcom 10GE phy with ID 0x206034, and several
Broadcom 10/100/1000 Phys in normal mode.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index e17b702..6a6b819 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -208,7 +208,7 @@
  * because the bus read/write functions may wait for an interrupt
  * to conclude the operation.
  */
-int mdiobus_read(struct mii_bus *bus, int addr, u16 regnum)
+int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
 {
 	int retval;
 
@@ -233,7 +233,7 @@
  * because the bus read/write functions may wait for an interrupt
  * to conclude the operation.
  */
-int mdiobus_write(struct mii_bus *bus, int addr, u16 regnum, u16 val)
+int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
 {
 	int err;