1 files changed, 99 insertions, 23 deletions

diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index 3bf27052832f..0aba760f7577 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -9,6 +9,8 @@
 
 #define pr_fmt(fmt)	"OF: " fmt
 
+#include <linux/cleanup.h>
+#include <linux/device.h>
 #include <linux/of.h>
 #include <linux/spinlock.h>
 #include <linux/slab.h>
@@ -305,15 +307,20 @@ int of_detach_node(struct device_node *np)
 }
 EXPORT_SYMBOL_GPL(of_detach_node);
 
+void __of_prop_free(struct property *prop)
+{
+	kfree(prop->name);
+	kfree(prop->value);
+	kfree(prop);
+}
+
 static void property_list_free(struct property *prop_list)
 {
 	struct property *prop, *next;
 
 	for (prop = prop_list; prop != NULL; prop = next) {
 		next = prop->next;
-		kfree(prop->name);
-		kfree(prop->value);
-		kfree(prop);
+		__of_prop_free(prop);
 	}
 }
 
@@ -426,9 +433,7 @@ struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags)
 	return new;
 
  err_free:
-	kfree(new->name);
-	kfree(new->value);
-	kfree(new);
+	__of_prop_free(new);
 	return NULL;
 }
 
@@ -470,9 +475,7 @@ struct device_node *__of_node_dup(const struct device_node *np,
 			if (!new_pp)
 				goto err_prop;
 			if (__of_add_property(node, new_pp)) {
-				kfree(new_pp->name);
-				kfree(new_pp->value);
-				kfree(new_pp);
+				__of_prop_free(new_pp);
 				goto err_prop;
 			}
 		}
@@ -533,7 +536,7 @@ static void __of_changeset_entry_destroy(struct of_changeset_entry *ce)
 	kfree(ce);
 }
 
-static void __of_changeset_entry_invert(struct of_changeset_entry *ce,
+static void __of_changeset_entry_invert(const struct of_changeset_entry *ce,
 					  struct of_changeset_entry *rce)
 {
 	memcpy(rce, ce, sizeof(*rce));
@@ -633,7 +636,7 @@ static int __of_changeset_entry_apply(struct of_changeset_entry *ce)
 	return 0;
 }
 
-static inline int __of_changeset_entry_revert(struct of_changeset_entry *ce)
+static inline int __of_changeset_entry_revert(const struct of_changeset_entry *ce)
 {
 	struct of_changeset_entry ce_inverted;
 
@@ -667,6 +670,17 @@ void of_changeset_destroy(struct of_changeset *ocs)
 {
 	struct of_changeset_entry *ce, *cen;
 
+	/*
+	 * When a device is deleted, the device links to/from it are also queued
+	 * for deletion. Until these device links are freed, the devices
+	 * themselves aren't freed. If the device being deleted is due to an
+	 * overlay change, this device might be holding a reference to a device
+	 * node that will be freed. So, wait until all already pending device
+	 * links are deleted before freeing a device node. This ensures we don't
+	 * free any device node that has a non-zero reference count.
+	 */
+	device_link_wait_removal();
+
 	list_for_each_entry_safe_reverse(ce, cen, &ocs->entries, node)
 		__of_changeset_entry_destroy(ce);
 }
@@ -921,11 +935,8 @@ static int of_changeset_add_prop_helper(struct of_changeset *ocs,
 		return -ENOMEM;
 
 	ret = of_changeset_add_property(ocs, np, new_pp);
-	if (ret) {
-		kfree(new_pp->name);
-		kfree(new_pp->value);
-		kfree(new_pp);
-	}
+	if (ret)
+		__of_prop_free(new_pp);
 
 	return ret;
 }
@@ -973,7 +984,7 @@ EXPORT_SYMBOL_GPL(of_changeset_add_prop_string);
 int of_changeset_add_prop_string_array(struct of_changeset *ocs,
 				       struct device_node *np,
 				       const char *prop_name,
-				       const char **str_array, size_t sz)
+				       const char * const *str_array, size_t sz)
 {
 	struct property prop;
 	int i, ret;
@@ -1021,10 +1032,9 @@ int of_changeset_add_prop_u32_array(struct of_changeset *ocs,
 				    const u32 *array, size_t sz)
 {
 	struct property prop;
-	__be32 *val;
-	int i, ret;
+	__be32 *val __free(kfree) = kcalloc(sz, sizeof(__be32), GFP_KERNEL);
+	int i;
 
-	val = kcalloc(sz, sizeof(__be32), GFP_KERNEL);
 	if (!val)
 		return -ENOMEM;
 
@@ -1034,9 +1044,75 @@ int of_changeset_add_prop_u32_array(struct of_changeset *ocs,
 	prop.length = sizeof(u32) * sz;
 	prop.value = (void *)val;
 
-	ret = of_changeset_add_prop_helper(ocs, np, &prop);
-	kfree(val);
+	return of_changeset_add_prop_helper(ocs, np, &prop);
+}
+EXPORT_SYMBOL_GPL(of_changeset_add_prop_u32_array);
+
+/**
+ * of_changeset_add_prop_bool - Add a boolean property (i.e. a property without
+ * any values) to a changeset.
+ *
+ * @ocs:	changeset pointer
+ * @np:		device node pointer
+ * @prop_name:	name of the property to be added
+ *
+ * Create a boolean property and add it to a changeset.
+ *
+ * Return: 0 on success, a negative error value in case of an error.
+ */
+int of_changeset_add_prop_bool(struct of_changeset *ocs, struct device_node *np,
+			       const char *prop_name)
+{
+	struct property prop;
+
+	prop.name = (char *)prop_name;
+	prop.length = 0;
+	prop.value = NULL;
+
+	return of_changeset_add_prop_helper(ocs, np, &prop);
+}
+EXPORT_SYMBOL_GPL(of_changeset_add_prop_bool);
+
+static int of_changeset_update_prop_helper(struct of_changeset *ocs,
+					   struct device_node *np,
+					   const struct property *pp)
+{
+	struct property *new_pp;
+	int ret;
+
+	new_pp = __of_prop_dup(pp, GFP_KERNEL);
+	if (!new_pp)
+		return -ENOMEM;
+
+	ret = of_changeset_update_property(ocs, np, new_pp);
+	if (ret)
+		__of_prop_free(new_pp);
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(of_changeset_add_prop_u32_array);
+
+/**
+ * of_changeset_update_prop_string - Add a string property update to a changeset
+ *
+ * @ocs:	changeset pointer
+ * @np:		device node pointer
+ * @prop_name:	name of the property to be updated
+ * @str:	pointer to null terminated string
+ *
+ * Create a string property to be updated and add it to a changeset.
+ *
+ * Return: 0 on success, a negative error value in case of an error.
+ */
+int of_changeset_update_prop_string(struct of_changeset *ocs,
+				    struct device_node *np,
+				    const char *prop_name, const char *str)
+{
+	struct property prop = {
+		.name = (char *)prop_name,
+		.length = strlen(str) + 1,
+		.value = (void *)str,
+	};
+
+	return of_changeset_update_prop_helper(ocs, np, &prop);
+}
+EXPORT_SYMBOL_GPL(of_changeset_update_prop_string);