Commit 97712f8f authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'mdio-fixes' 



Saravana Kannan says:

====================
Clean up and fix error handling in mdio_mux_init()

This patch series was started due to -EPROBE_DEFER not being handled
correctly in mdio_mux_init() and causing issues [1]. While at it, I also
did some more error handling fixes and clean ups. The -EPROBE_DEFER fix is
the last patch.

Ideally, in the last patch we'd treat any error similar to -EPROBE_DEFER
but I'm not sure if it'll break any board/platforms where some child
mdiobus never successfully registers. If we treated all errors similar to
-EPROBE_DEFER, then none of the child mdiobus will work and that might be a
regression. If people are sure this is not a real case, then I can fix up
the last patch to always fail the entire mdio-mux init if any of the child
mdiobus registration fails.
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents ed5d2937 7bd0cef5

drivers/net/mdio/mdio-mux.c

+24 −13
Original line number Diff line number Diff line
@@ -82,6 +82,17 @@ static int mdio_mux_write(struct mii_bus *bus, int phy_id, 


static int parent_count;



static void mdio_mux_uninit_children(struct mdio_mux_parent_bus *pb)

{

	struct mdio_mux_child_bus *cb = pb->children;



	while (cb) {

		mdiobus_unregister(cb->mii_bus);

		mdiobus_free(cb->mii_bus);

		cb = cb->next;

	}

}



int mdio_mux_init(struct device *dev,

		  struct device_node *mux_node,

		  int (*switch_fn)(int cur, int desired, void *data),
@@ -144,7 +155,7 @@ int mdio_mux_init(struct device *dev, 
		cb = devm_kzalloc(dev, sizeof(*cb), GFP_KERNEL);

		if (!cb) {

			ret_val = -ENOMEM;

			continue;

			goto err_loop;

		}

		cb->bus_number = v;

		cb->parent = pb;
@@ -152,8 +163,7 @@ int mdio_mux_init(struct device *dev, 
		cb->mii_bus = mdiobus_alloc();

		if (!cb->mii_bus) {

			ret_val = -ENOMEM;

			devm_kfree(dev, cb);

			continue;

			goto err_loop;

		}

		cb->mii_bus->priv = cb;
@@ -165,11 +175,15 @@ int mdio_mux_init(struct device *dev, 
		cb->mii_bus->write = mdio_mux_write;

		r = of_mdiobus_register(cb->mii_bus, child_bus_node);

		if (r) {

			mdiobus_free(cb->mii_bus);

			if (r == -EPROBE_DEFER) {

				ret_val = r;

				goto err_loop;

			}

			devm_kfree(dev, cb);

			dev_err(dev,

				"Error: Failed to register MDIO bus for child %pOF\n",

				child_bus_node);

			mdiobus_free(cb->mii_bus);

			devm_kfree(dev, cb);

		} else {

			cb->next = pb->children;

			pb->children = cb;
@@ -181,7 +195,10 @@ int mdio_mux_init(struct device *dev, 
	}



	dev_err(dev, "Error: No acceptable child buses found\n");

	devm_kfree(dev, pb);



err_loop:

	mdio_mux_uninit_children(pb);

	of_node_put(child_bus_node);

err_pb_kz:

	put_device(&parent_bus->dev);

err_parent_bus:
@@ -193,14 +210,8 @@ EXPORT_SYMBOL_GPL(mdio_mux_init); 
void mdio_mux_uninit(void *mux_handle)

{

	struct mdio_mux_parent_bus *pb = mux_handle;

	struct mdio_mux_child_bus *cb = pb->children;



	while (cb) {

		mdiobus_unregister(cb->mii_bus);

		mdiobus_free(cb->mii_bus);

		cb = cb->next;

	}



	mdio_mux_uninit_children(pb);

	put_device(&pb->mii_bus->dev);

}

EXPORT_SYMBOL_GPL(mdio_mux_uninit);