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;
+}