1 files changed, 55 insertions, 13 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 7c79e94a35ea..cd17092b82bd 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -329,6 +329,41 @@ struct device_node *of_find_compatible_node(struct device_node *from,
 EXPORT_SYMBOL(of_find_compatible_node);
 
 /**
+ *      of_find_node_with_property - Find a node which has a property with
+ *                                   the given name.
+ *      @from:          The node to start searching from or NULL, the node
+ *                      you pass will not be searched, only the next one
+ *                      will; typically, you pass what the previous call
+ *                      returned. of_node_put() will be called on it
+ *      @prop_name:     The name of the property to look for.
+ *
+ *      Returns a node pointer with refcount incremented, use
+ *      of_node_put() on it when done.
+ */
+struct device_node *of_find_node_with_property(struct device_node *from,
+        const char *prop_name)
+{
+        struct device_node *np;
+        struct property *pp;
+
+        read_lock(&devtree_lock);
+        np = from ? from->allnext : allnodes;
+        for (; np; np = np->allnext) {
+                for (pp = np->properties; pp != 0; pp = pp->next) {
+                        if (of_prop_cmp(pp->name, prop_name) == 0) {
+                                of_node_get(np);
+                                goto out;
+                        }
+                }
+        }
+out:
+        of_node_put(from);
+        read_unlock(&devtree_lock);
+        return np;
+}
+EXPORT_SYMBOL(of_find_node_with_property);
+
+/**
  * of_match_node - Tell if an device_node has a matching of_match structure
  *      @matches:       array of of device match structures to search in
  *      @node:          the of device structure to match against
@@ -464,8 +499,8 @@ EXPORT_SYMBOL_GPL(of_modalias_node);
  * @list_name:  property name that contains a list
  * @cells_name: property name that specifies phandles' arguments count
  * @index:      index of a phandle to parse out
- * @out_node:   pointer to device_node struct pointer (will be filled)
- * @out_args:   pointer to arguments pointer (will be filled)
+ * @out_node:   optional pointer to device_node struct pointer (will be filled)
+ * @out_args:   optional pointer to arguments pointer (will be filled)
  *
  * This function is useful to parse lists of phandles and their arguments.
  * Returns 0 on success and fills out_node and out_args, on error returns
@@ -499,7 +534,7 @@ int of_parse_phandles_with_args(struct device_node *np, const char *list_name,
         int size;
         int cur_index = 0;
         struct device_node *node = NULL;
-        const void *args;
+        const void *args = NULL;
 
         list = of_get_property(np, list_name, &size);
         if (!list) {
@@ -512,14 +547,12 @@ int of_parse_phandles_with_args(struct device_node *np, const char *list_name,
                 const u32 *cells;
                 const phandle *phandle;
 
-                phandle = list;
-                args = list + 1;
+                phandle = list++;
+                args = list;
 
                 /* one cell hole in the list = <>; */
-                if (!*phandle) {
-                        list++;
+                if (!*phandle)
                         goto next;
-                }
 
                 node = of_find_node_by_phandle(*phandle);
                 if (!node) {
@@ -535,8 +568,7 @@ int of_parse_phandles_with_args(struct device_node *np, const char *list_name,
                         goto err1;
                 }
 
-                /* Next phandle is at offset of one phandle cell + #cells */
-                list += 1 + *cells;
+                list += *cells;
                 if (list > list_end) {
                         pr_debug("%s: insufficient arguments length\n",
                                  np->full_name);
@@ -548,16 +580,26 @@ next:
 
                 of_node_put(node);
                 node = NULL;
+                args = NULL;
                 cur_index++;
         }
 
         if (!node) {
-                ret = -ENOENT;
+                /*
+                 * args w/o node indicates that the loop above has stopped at
+                 * the 'hole' cell. Report this differently.
+                 */
+                if (args)
+                        ret = -EEXIST;
+                else
+                        ret = -ENOENT;
                 goto err0;
         }
 
-        *out_node = node;
-        *out_args = args;
+        if (out_node)
+                *out_node = node;
+        if (out_args)
+                *out_args = args;
 
         return 0;
 err1: