1 files changed, 116 insertions, 0 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c
index e6627b2320f1..ec56739eb247 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -658,3 +658,119 @@ err0:
 	return ret;
 }
 EXPORT_SYMBOL(of_parse_phandles_with_args);
+
+/**
+ * prom_add_property - Add a property to a node
+ */
+int prom_add_property(struct device_node *np, struct property *prop)
+{
+	struct property **next;
+	unsigned long flags;
+
+	prop->next = NULL;
+	write_lock_irqsave(&devtree_lock, flags);
+	next = &np->properties;
+	while (*next) {
+		if (strcmp(prop->name, (*next)->name) == 0) {
+			/* duplicate ! don't insert it */
+			write_unlock_irqrestore(&devtree_lock, flags);
+			return -1;
+		}
+		next = &(*next)->next;
+	}
+	*next = prop;
+	write_unlock_irqrestore(&devtree_lock, flags);
+
+#ifdef CONFIG_PROC_DEVICETREE
+	/* try to add to proc as well if it was initialized */
+	if (np->pde)
+		proc_device_tree_add_prop(np->pde, prop);
+#endif /* CONFIG_PROC_DEVICETREE */
+
+	return 0;
+}
+
+/**
+ * prom_remove_property - Remove a property from a node.
+ *
+ * Note that we don't actually remove it, since we have given out
+ * who-knows-how-many pointers to the data using get-property.
+ * Instead we just move the property to the "dead properties"
+ * list, so it won't be found any more.
+ */
+int prom_remove_property(struct device_node *np, struct property *prop)
+{
+	struct property **next;
+	unsigned long flags;
+	int found = 0;
+
+	write_lock_irqsave(&devtree_lock, flags);
+	next = &np->properties;
+	while (*next) {
+		if (*next == prop) {
+			/* found the node */
+			*next = prop->next;
+			prop->next = np->deadprops;
+			np->deadprops = prop;
+			found = 1;
+			break;
+		}
+		next = &(*next)->next;
+	}
+	write_unlock_irqrestore(&devtree_lock, flags);
+
+	if (!found)
+		return -ENODEV;
+
+#ifdef CONFIG_PROC_DEVICETREE
+	/* try to remove the proc node as well */
+	if (np->pde)
+		proc_device_tree_remove_prop(np->pde, prop);
+#endif /* CONFIG_PROC_DEVICETREE */
+
+	return 0;
+}
+
+/*
+ * prom_update_property - Update a property in a node.
+ *
+ * Note that we don't actually remove it, since we have given out
+ * who-knows-how-many pointers to the data using get-property.
+ * Instead we just move the property to the "dead properties" list,
+ * and add the new property to the property list
+ */
+int prom_update_property(struct device_node *np,
+			 struct property *newprop,
+			 struct property *oldprop)
+{
+	struct property **next;
+	unsigned long flags;
+	int found = 0;
+
+	write_lock_irqsave(&devtree_lock, flags);
+	next = &np->properties;
+	while (*next) {
+		if (*next == oldprop) {
+			/* found the node */
+			newprop->next = oldprop->next;
+			*next = newprop;
+			oldprop->next = np->deadprops;
+			np->deadprops = oldprop;
+			found = 1;
+			break;
+		}
+		next = &(*next)->next;
+	}
+	write_unlock_irqrestore(&devtree_lock, flags);
+
+	if (!found)
+		return -ENODEV;
+
+#ifdef CONFIG_PROC_DEVICETREE
+	/* try to add to proc as well if it was initialized */
+	if (np->pde)
+		proc_device_tree_update_prop(np->pde, newprop, oldprop);
+#endif /* CONFIG_PROC_DEVICETREE */
+
+	return 0;
+}