Merge tag 'devicetree-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git...

[karo-tx-linux.git] / drivers / of / base.c

diff --git a/drivers/of/base.c b/drivers/of/base.c
index aab9728271fdbfe27b199a9325bfed84063b928d..8368d96ae7b44d3ce7b74b37abe3eac6cac76191 100644 (file)
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -695,6 +695,25 @@ struct device_node *of_get_next_parent(struct device_node *node)
 }
 EXPORT_SYMBOL(of_get_next_parent);
 
+static struct device_node *__of_get_next_child(const struct device_node *node,
+                                               struct device_node *prev)
+{
+       struct device_node *next;
+
+       if (!node)
+               return NULL;
+
+       next = prev ? prev->sibling : node->child;
+       for (; next; next = next->sibling)
+               if (of_node_get(next))
+                       break;
+       of_node_put(prev);
+       return next;
+}
+#define __for_each_child_of_node(parent, child) \
+       for (child = __of_get_next_child(parent, NULL); child != NULL; \
+            child = __of_get_next_child(parent, child))
+
 /**
  *     of_get_next_child - Iterate a node childs
  *     @node:  parent node
@@ -710,11 +729,7 @@ struct device_node *of_get_next_child(const struct device_node *node,
        unsigned long flags;
 
        raw_spin_lock_irqsave(&devtree_lock, flags);
-       next = prev ? prev->sibling : node->child;
-       for (; next; next = next->sibling)
-               if (of_node_get(next))
-                       break;
-       of_node_put(prev);
+       next = __of_get_next_child(node, prev);
        raw_spin_unlock_irqrestore(&devtree_lock, flags);
        return next;
 }
@@ -734,6 +749,9 @@ struct device_node *of_get_next_available_child(const struct device_node *node,
        struct device_node *next;
        unsigned long flags;
 
+       if (!node)
+               return NULL;
+
        raw_spin_lock_irqsave(&devtree_lock, flags);
        next = prev ? prev->sibling : node->child;
        for (; next; next = next->sibling) {
@@ -771,23 +789,78 @@ struct device_node *of_get_child_by_name(const struct device_node *node,
 }
 EXPORT_SYMBOL(of_get_child_by_name);
 
+static struct device_node *__of_find_node_by_path(struct device_node *parent,
+                                               const char *path)
+{
+       struct device_node *child;
+       int len = strchrnul(path, '/') - path;
+
+       if (!len)
+               return NULL;
+
+       __for_each_child_of_node(parent, child) {
+               const char *name = strrchr(child->full_name, '/');
+               if (WARN(!name, "malformed device_node %s\n", child->full_name))
+                       continue;
+               name++;
+               if (strncmp(path, name, len) == 0 && (strlen(name) == len))
+                       return child;
+       }
+       return NULL;
+}
+
 /**
  *     of_find_node_by_path - Find a node matching a full OF path
- *     @path:  The full path to match
+ *     @path: Either the full path to match, or if the path does not
+ *            start with '/', the name of a property of the /aliases
+ *            node (an alias).  In the case of an alias, the node
+ *            matching the alias' value will be returned.
+ *
+ *     Valid paths:
+ *             /foo/bar        Full path
+ *             foo             Valid alias
+ *             foo/bar         Valid alias + relative path
  *
  *     Returns a node pointer with refcount incremented, use
  *     of_node_put() on it when done.
  */
 struct device_node *of_find_node_by_path(const char *path)
 {
-       struct device_node *np = of_allnodes;
+       struct device_node *np = NULL;
+       struct property *pp;
        unsigned long flags;
 
+       if (strcmp(path, "/") == 0)
+               return of_node_get(of_allnodes);
+
+       /* The path could begin with an alias */
+       if (*path != '/') {
+               char *p = strchrnul(path, '/');
+               int len = p - path;
+
+               /* of_aliases must not be NULL */
+               if (!of_aliases)
+                       return NULL;
+
+               for_each_property_of_node(of_aliases, pp) {
+                       if (strlen(pp->name) == len && !strncmp(pp->name, path, len)) {
+                               np = of_find_node_by_path(pp->value);
+                               break;
+                       }
+               }
+               if (!np)
+                       return NULL;
+               path = p;
+       }
+
+       /* Step down the tree matching path components */
        raw_spin_lock_irqsave(&devtree_lock, flags);
-       for (; np; np = np->allnext) {
-               if (np->full_name && (of_node_cmp(np->full_name, path) == 0)
-                   && of_node_get(np))
-                       break;
+       if (!np)
+               np = of_node_get(of_allnodes);
+       while (np && *path == '/') {
+               path++; /* Increment past '/' delimiter */
+               np = __of_find_node_by_path(np, path);
+               path = strchrnul(path, '/');
        }
        raw_spin_unlock_irqrestore(&devtree_lock, flags);
        return np;
@@ -1800,7 +1873,7 @@ int of_update_property(struct device_node *np, struct property *newprop)
 {
        struct property **next, *oldprop;
        unsigned long flags;
-       int rc, found = 0;
+       int rc;
 
        rc = of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop);
        if (rc)
@@ -1809,34 +1882,34 @@ int of_update_property(struct device_node *np, struct property *newprop)
        if (!newprop->name)
                return -EINVAL;
 
-       oldprop = of_find_property(np, newprop->name, NULL);
-       if (!oldprop)
-               return of_add_property(np, newprop);
-
        raw_spin_lock_irqsave(&devtree_lock, flags);
        next = &np->properties;
-       while (*next) {
+       oldprop = __of_find_property(np, newprop->name, NULL);
+       if (!oldprop) {
+               /* add the new node */
+               rc = __of_add_property(np, newprop);
+       } else while (*next) {
+               /* replace the node */
                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;
        }
        raw_spin_unlock_irqrestore(&devtree_lock, flags);
-       if (!found)
-               return -ENODEV;
+       if (rc)
+               return rc;
 
        /* At early boot, bail out and defer setup to of_init() */
        if (!of_kset)
-               return found ? 0 : -ENODEV;
+               return 0;
 
        /* Update the sysfs attribute */
-       sysfs_remove_bin_file(&np->kobj, &oldprop->attr);
+       if (oldprop)
+               sysfs_remove_bin_file(&np->kobj, &oldprop->attr);
        __of_add_property_sysfs(np, newprop);
 
        return 0;