Currently all paths passed to of_find_node_by_path() must begin with a
'/', indicating a full path to the desired node.
Augment the look-up code so that if a path does *not* begin with '/',
the path is used as the name of an /aliases property. The value of
this alias is then used as the full node path to be found.
Signed-off-by: David Daney <ddaney@xxxxxxxxxxxxxxxxxx>
---
drivers/of/base.c | 48 +++++++++++++++++++++++++++++++++++++++++++++---
1 files changed, 45 insertions(+), 3 deletions(-)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 632ebae..279134b 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -340,22 +340,64 @@ EXPORT_SYMBOL(of_get_next_child);
/**
* of_find_node_by_path - Find a node matching a full OF path
- * @path: The full path to match
+ * @path: Either the full path to match, or if the path does not
+ * start with '/', the name of a property of the /aliases
+ * node (an alias). In the case of an alias, the node
+ * matching the alias' value will be returned.
*
* Returns a node pointer with refcount incremented, use
* of_node_put() on it when done.
*/
struct device_node *of_find_node_by_path(const char *path)
{
- struct device_node *np = allnodes;
+ struct device_node *np = NULL;
+ struct device_node *aliases = NULL;
+ char *alias = NULL;
+ char *new_path = NULL;
read_lock(&devtree_lock);
- for (; np; np = np->allnext) {
+
+ if (path[0] != '/') {
+ const char *ps;
+ aliases = of_find_node_by_path("/aliases");
+ if (!aliases)
+ goto out;
+
+ ps = strchr(path, '/');
+ if (ps) {
+ size_t len = ps - path;
+ alias = kstrndup(path, len, GFP_KERNEL);
+ if (!alias)
+ goto out;
+ path = of_get_property(aliases, alias, NULL);
+ if (!path)
+ goto out;
+
+ len = strlen(path) + strlen(ps) + 1;
+ new_path = kmalloc(len, GFP_KERNEL);
+ if (!new_path)
+ goto out;
+ strcpy(new_path, path);
+ strcat(new_path, ps);
+ path = new_path;
+ } else {
+ path = of_get_property(aliases, path, NULL);
+ }
+ if (!path)
+ goto out;
+ }
+
+ for (np = allnodes; np; np = np->allnext) {
if (np->full_name && (of_node_cmp(np->full_name, path) == 0)
&& of_node_get(np))
break;
}
+out:
+ if (aliases)
+ of_node_put(aliases);
read_unlock(&devtree_lock);
+ kfree(alias);
+ kfree(new_path);
return np;
}
EXPORT_SYMBOL(of_find_node_by_path);
--
1.7.2.3
