of: merge of_find_node_by_phandle

Merge common function between powerpc, sparc and microblaze. Code is
identical for powerpc and microblaze, but adds a lock (and release) of
the devtree_lock on sparc.

Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 21 insertions, 0 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 2ce58be314af..785e9cc1b207 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -615,6 +615,27 @@ int of_modalias_node(struct device_node *node, char *modalias, int len)
 EXPORT_SYMBOL_GPL(of_modalias_node);
 
 /**
+ * of_find_node_by_phandle - Find a node given a phandle
+ * @handle:     phandle of the node to find
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+struct device_node *of_find_node_by_phandle(phandle handle)
+{
+        struct device_node *np;
+
+        read_lock(&devtree_lock);
+        for (np = allnodes; np; np = np->allnext)
+                if (np->phandle == handle)
+                        break;
+        of_node_get(np);
+        read_unlock(&devtree_lock);
+        return np;
+}
+EXPORT_SYMBOL(of_find_node_by_phandle);
+
+/**
  * of_parse_phandle - Resolve a phandle property to a device_node pointer
  * @np: Pointer to device node holding phandle property
  * @phandle_name: Name of property holding a phandle value