[PATCH 02/10] of: Add convenience functions to en/disable devicenodes

[Sascha Hauer]

These functions allow to manipulate the "status" property of
devicenodes effectively enabling/disabling devices.

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 drivers/of/base.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 include/of.h      |  5 +++++
 2 files changed, 70 insertions(+)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 7bee912..9559bff 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1752,3 +1752,68 @@ int of_add_initrd(struct device_node *root, resource_size_t start,
 
 	return 0;
 }
+
+/**
+ * of_device_enable - enable a devicenode device
+ * @node - the node to enable
+ *
+ * This deletes the status property of a devicenode effectively
+ * enabling the device.
+ */
+int of_device_enable(struct device_node *node)
+{
+	struct property *pp;
+
+	pp = of_find_property(node, "status", NULL);
+	if (!pp)
+		return 0;
+
+	of_delete_property(pp);
+
+	return 0;
+}
+
+/**
+ * of_device_enable_path - enable a devicenode
+ * @path - the nodepath to enable
+ *
+ * wrapper around of_device_enable taking the nodepath as argument
+ */
+int of_device_enable_path(const char *path)
+{
+	struct device_node *node;
+
+	node = of_find_node_by_path(path);
+	if (!node)
+		return -ENODEV;
+
+	return of_device_enable(node);
+}
+
+/**
+ * of_device_enable - disable a devicenode device
+ * @node - the node to disable
+ *
+ * This sets the status of a devicenode to "disabled"
+ */
+int of_device_disable(struct device_node *node)
+{
+	return of_set_property(node, "status", "disabled", sizeof("disabled"), 1);
+}
+
+/**
+ * of_device_disable_path - disable a devicenode
+ * @path - the nodepath to disable
+ *
+ * wrapper around of_device_disable taking the nodepath as argument
+ */
+int of_device_disable_path(const char *path)
+{
+	struct device_node *node;
+
+	node = of_find_node_by_path(path);
+	if (!node)
+		return -ENODEV;
+
+	return of_device_disable(node);
+}
diff --git a/include/of.h b/include/of.h
index 710383c..7b600f0 100644
--- a/include/of.h
+++ b/include/of.h
@@ -682,4 +682,9 @@ static inline int of_property_write_u64(struct device_node *np,
 
 extern const struct of_device_id of_default_bus_match_table[];
 
+int of_device_enable(struct device_node *node);
+int of_device_enable_path(const char *path);
+int of_device_disable(struct device_node *node);
+int of_device_disable_path(const char *path);
+
 #endif /* __OF_H */
-- 
1.8.3.2