[PATCH 2/2] of: add of_node_read()

[Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>]

From: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>

We are counting of node by using of_node_get/put(), but
not have of_node_read() which can be used to check count.
Let's add it

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
---
 drivers/of/dynamic.c | 14 ++++++++++++++
 include/linux/of.h   |  5 +++++
 2 files changed, 19 insertions(+)

diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index f4f8ed9..db5fdf3 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -49,6 +49,20 @@ void of_node_put(struct device_node *node)
 }
 EXPORT_SYMBOL(of_node_put);
 
+/**
+ * of_node_read() - read refcount of a node
+ * @node:	Node to dec refcount, NULL is supported to simplify writing of
+ *		callers
+ */
+unsigned int of_node_read(struct device_node *node)
+{
+	if (node)
+		return kobject_read(&node->kobj);
+
+	return 0;
+}
+EXPORT_SYMBOL(of_node_read);
+
 static BLOCKING_NOTIFIER_HEAD(of_reconfig_chain);
 
 int of_reconfig_notifier_register(struct notifier_block *nb)
diff --git a/include/linux/of.h b/include/linux/of.h
index 4d25e4f..8be0ca8 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -122,6 +122,7 @@ static inline void of_node_init(struct device_node *node)
 #ifdef CONFIG_OF_DYNAMIC
 extern struct device_node *of_node_get(struct device_node *node);
 extern void of_node_put(struct device_node *node);
+unsigned int of_node_read(struct device_node *node);
 #else /* CONFIG_OF_DYNAMIC */
 /* Dummy ref counting routines - to be implemented later */
 static inline struct device_node *of_node_get(struct device_node *node)
@@ -129,6 +130,10 @@ static inline struct device_node *of_node_get(struct device_node *node)
 	return node;
 }
 static inline void of_node_put(struct device_node *node) { }
+static inline unsigned int of_node_read(struct device_node *node)
+{
+	return 0;
+}
 #endif /* !CONFIG_OF_DYNAMIC */
 
 /* Pointer for first entry in chain of all nodes. */
-- 
1.9.1