of: Merge of_node_get() and of_node_put()

Merge common code between PowerPC and MicroBlaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 75 insertions, 0 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index dba995b70b8..cf89ee6253f 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -60,6 +60,81 @@ int of_n_size_cells(struct device_node *np)
 }
 EXPORT_SYMBOL(of_n_size_cells);
 
+#if !defined(CONFIG_SPARC)   /* SPARC doesn't do ref counting (yet) */
+/**
+ *      of_node_get - Increment refcount of a node
+ *      @node:  Node to inc refcount, NULL is supported to
+ *              simplify writing of callers
+ *
+ *      Returns node.
+ */
+struct device_node *of_node_get(struct device_node *node)
+{
+        if (node)
+                kref_get(&node->kref);
+        return node;
+}
+EXPORT_SYMBOL(of_node_get);
+
+static inline struct device_node *kref_to_device_node(struct kref *kref)
+{
+        return container_of(kref, struct device_node, kref);
+}
+
+/**
+ *      of_node_release - release a dynamically allocated node
+ *      @kref:  kref element of the node to be released
+ *
+ *      In of_node_put() this function is passed to kref_put()
+ *      as the destructor.
+ */
+static void of_node_release(struct kref *kref)
+{
+        struct device_node *node = kref_to_device_node(kref);
+        struct property *prop = node->properties;
+
+        /* We should never be releasing nodes that haven't been detached. */
+        if (!of_node_check_flag(node, OF_DETACHED)) {
+                pr_err("ERROR: Bad of_node_put() on %s\n", node->full_name);
+                dump_stack();
+                kref_init(&node->kref);
+                return;
+        }
+
+        if (!of_node_check_flag(node, OF_DYNAMIC))
+                return;
+
+        while (prop) {
+                struct property *next = prop->next;
+                kfree(prop->name);
+                kfree(prop->value);
+                kfree(prop);
+                prop = next;
+
+                if (!prop) {
+                        prop = node->deadprops;
+                        node->deadprops = NULL;
+                }
+        }
+        kfree(node->full_name);
+        kfree(node->data);
+        kfree(node);
+}
+
+/**
+ *      of_node_put - Decrement refcount of a node
+ *      @node:  Node to dec refcount, NULL is supported to
+ *              simplify writing of callers
+ *
+ */
+void of_node_put(struct device_node *node)
+{
+        if (node)
+                kref_put(&node->kref, of_node_release);
+}
+EXPORT_SYMBOL(of_node_put);
+#endif /* !CONFIG_SPARC */
+
 struct property *of_find_property(const struct device_node *np,
                                   const char *name,
                                   int *lenp)