netdev/of/phy: New function: of_mdio_find_bus().
Add of_mdio_find_bus() which allows an mii_bus to be located given its
associated the device tree node.
This is needed by the follow-on patch to add a driver for MDIO bus
multiplexers.
The of_mdiobus_register() function is modified so that the device tree
node is recorded in the mii_bus. Then we can find it again by
iterating over all mdio_bus_class devices.
Because the OF device tree has now become an integral part of the
kernel, this can live in mdio_bus.c (which contains the needed
mdio_bus_class structure) instead of of_mdio.c.
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: "David S. Miller" <davem@davemloft.net>
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 8985cc6..83d5c9f 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -88,6 +88,38 @@
.dev_release = mdiobus_release,
};
+#ifdef CONFIG_OF_MDIO
+/* Helper function for of_mdio_find_bus */
+static int of_mdio_bus_match(struct device *dev, void *mdio_bus_np)
+{
+ return dev->of_node == mdio_bus_np;
+}
+/**
+ * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
+ * @mdio_np: Pointer to the mii_bus.
+ *
+ * Returns a pointer to the mii_bus, or NULL if none found.
+ *
+ * Because the association of a device_node and mii_bus is made via
+ * of_mdiobus_register(), the mii_bus cannot be found before it is
+ * registered with of_mdiobus_register().
+ *
+ */
+struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
+{
+ struct device *d;
+
+ if (!mdio_bus_np)
+ return NULL;
+
+ d = class_find_device(&mdio_bus_class, NULL, mdio_bus_np,
+ of_mdio_bus_match);
+
+ return d ? to_mii_bus(d) : NULL;
+}
+EXPORT_SYMBOL(of_mdio_find_bus);
+#endif
+
/**
* mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
* @bus: target mii_bus