[PATCH 1/2] dt: introduce for_each_available_child_of_node, of_get_next_available_child
Timur Tabi
timur at freescale.com
Wed Aug 15 09:20:23 EST 2012
Macro for_each_child_of_node() makes it easy to iterate over all of the
children for a given device tree node, including those nodes that are
marked as unavailable (i.e. status = "disabled").
Introduce for_each_available_child_of_node(), which is like
for_each_child_of_node(), but it automatically skips unavailable nodes.
This also requires the introduction of helper function
of_get_next_available_child(), which returns the next available child
node.
Signed-off-by: Timur Tabi <timur at freescale.com>
---
drivers/of/base.c | 27 +++++++++++++++++++++++++++
include/linux/of.h | 7 +++++++
2 files changed, 34 insertions(+), 0 deletions(-)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index c181b94..d4a1c9a 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -364,6 +364,33 @@ struct device_node *of_get_next_child(const struct device_node *node,
EXPORT_SYMBOL(of_get_next_child);
/**
+ * of_get_next_available_child - Find the next available child node
+ * @node: parent node
+ * @prev: previous child of the parent node, or NULL to get first
+ *
+ * This function is like of_get_next_child(), except that it
+ * automatically skips any disabled nodes (i.e. status = "disabled").
+ */
+struct device_node *of_get_next_available_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_device_is_available(next))
+ continue;
+ if (of_node_get(next))
+ break;
+ }
+ of_node_put(prev);
+ read_unlock(&devtree_lock);
+ return next;
+}
+EXPORT_SYMBOL(of_get_next_available_child);
+
+/**
* of_find_node_by_path - Find a node matching a full OF path
* @path: The full path to match
*
diff --git a/include/linux/of.h b/include/linux/of.h
index 5919ee3..1b11632 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -190,10 +190,17 @@ extern struct device_node *of_get_parent(const struct device_node *node);
extern struct device_node *of_get_next_parent(struct device_node *node);
extern struct device_node *of_get_next_child(const struct device_node *node,
struct device_node *prev);
+extern struct device_node *of_get_next_available_child(
+ const struct device_node *node, struct device_node *prev);
+
#define for_each_child_of_node(parent, child) \
for (child = of_get_next_child(parent, NULL); child != NULL; \
child = of_get_next_child(parent, child))
+#define for_each_available_child_of_node(parent, child) \
+ for (child = of_get_next_available_child(parent, NULL); child != NULL; \
+ child = of_get_next_available_child(parent, child))
+
static inline int of_get_child_count(const struct device_node *np)
{
struct device_node *child;
--
1.7.3.4
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