mdio: mux: make child bus walking more permissive and errors more verbose

If any errors are encountered while walking the device tree structure of
the MDIO bus for children, the code may silently continue, silently
exit, or throw an error and exit.  This make it difficult for device
tree writers to know there is an error.  Also, it makes any error in a
child entry of the MDIO bus be fatal for all entries.  Instead, we
should provide verbose errors describing the error and then attempt to
continue if it all possible.  Also, use of_mdio_parse_addr()

Signed-off-by: Jon Mason <jon.mason@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jon Mason 2017-05-31 15:44:50 -04:00 committed by David S. Miller
parent e8317a4038
commit 342fa19644

View File

@ -135,27 +135,33 @@ int mdio_mux_init(struct device *dev,
for_each_available_child_of_node(dev->of_node, child_bus_node) {
u32 v;
r = of_property_read_u32(child_bus_node, "reg", &v);
if (r)
v = of_mdio_parse_addr(dev, child_bus_node);
if (v < 0) {
dev_err(dev,
"Error: Failed to find reg for child %s\n",
of_node_full_name(child_bus_node));
continue;
}
cb = devm_kzalloc(dev, sizeof(*cb), GFP_KERNEL);
if (cb == NULL) {
dev_err(dev,
"Error: Failed to allocate memory for child\n");
"Error: Failed to allocate memory for child %s\n",
of_node_full_name(child_bus_node));
ret_val = -ENOMEM;
of_node_put(child_bus_node);
break;
continue;
}
cb->bus_number = v;
cb->parent = pb;
cb->mii_bus = mdiobus_alloc();
if (!cb->mii_bus) {
dev_err(dev,
"Error: Failed to allocate MDIO bus for child %s\n",
of_node_full_name(child_bus_node));
ret_val = -ENOMEM;
devm_kfree(dev, cb);
of_node_put(child_bus_node);
break;
continue;
}
cb->mii_bus->priv = cb;
@ -167,6 +173,9 @@ 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) {
dev_err(dev,
"Error: Failed to register MDIO bus for child %s\n",
of_node_full_name(child_bus_node));
mdiobus_free(cb->mii_bus);
devm_kfree(dev, cb);
} else {
@ -180,6 +189,7 @@ int mdio_mux_init(struct device *dev,
return 0;
}
dev_err(dev, "Error: No acceptable child buses found\n");
devm_kfree(dev, pb);
err_pb_kz:
/* balance the reference of_mdio_find_bus() took */