Consolidate of_get_next_child

This adds a read_lock around the child/next accesses on Sparc.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: David S. Miller <davem@davemloft.net>

1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 82bb78680ff6..6b6dfcc56522 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -134,3 +134,27 @@ struct device_node *of_get_parent(const struct device_node *node)
         return np;
 }
 EXPORT_SYMBOL(of_get_parent);
+
+/**
+ *      of_get_next_child - Iterate a node childs
+ *      @node:  parent node
+ *      @prev:  previous child of the parent node, or NULL to get first
+ *
+ *      Returns a node pointer with refcount incremented, use
+ *      of_node_put() on it when done.
+ */
+struct device_node *of_get_next_child(const struct device_node *node,
+        struct device_node *prev)
+{
+        struct device_node *next;
+
+        read_lock(&devtree_lock);
+        next = prev ? prev->sibling : node->child;
+        for (; next; next = next->sibling)
+                if (of_node_get(next))
+                        break;
+        of_node_put(prev);
+        read_unlock(&devtree_lock);
+        return next;
+}
+EXPORT_SYMBOL(of_get_next_child);