[PATCH v6 1/3] netdev/of/phy: New function: of_mdio_find_bus().

From: David Daney
Date: Wed May 02 2012 - 21:16:44 EST


From: David Daney <david.daney@xxxxxxxxxx>

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@xxxxxxxxxx>
Cc: Grant Likely <grant.likely@xxxxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
---
drivers/net/phy/mdio_bus.c | 32 ++++++++++++++++++++++++++++++++
drivers/of/of_mdio.c | 2 ++
include/linux/of_mdio.h | 2 ++
3 files changed, 36 insertions(+), 0 deletions(-)

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 @@ static struct class mdio_bus_class = {
.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
diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c
index 483c0ad..2574abd 100644
--- a/drivers/of/of_mdio.c
+++ b/drivers/of/of_mdio.c
@@ -45,6 +45,8 @@ int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
for (i=0; i<PHY_MAX_ADDR; i++)
mdio->irq[i] = PHY_POLL;

+ mdio->dev.of_node = np;
+
/* Register the MDIO bus */
rc = mdiobus_register(mdio);
if (rc)
diff --git a/include/linux/of_mdio.h b/include/linux/of_mdio.h
index 53b94e0..912c27a 100644
--- a/include/linux/of_mdio.h
+++ b/include/linux/of_mdio.h
@@ -22,4 +22,6 @@ extern struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
void (*hndlr)(struct net_device *),
phy_interface_t iface);

+extern struct mii_bus *of_mdio_find_bus(struct device_node *mdio_np);
+
#endif /* __LINUX_OF_MDIO_H */
--
1.7.2.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/