1 files changed, 142 insertions, 67 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 4557a142c75..b9864806e9b 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -227,7 +227,8 @@ static int __of_node_add(struct device_node *np)
 	np->kobj.kset = of_kset;
 	if (!np->parent) {
 		/* Nodes without parents are new top level trees */
-		rc = kobject_add(&np->kobj, NULL, safe_name(&of_kset->kobj, "base"));
+		rc = kobject_add(&np->kobj, NULL, "%s",
+				 safe_name(&of_kset->kobj, "base"));
 	} else {
 		name = safe_name(&np->parent->kobj, kbasename(np->full_name));
 		if (!name || !name[0])
@@ -695,6 +696,25 @@ 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 +730,7 @@ 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 +750,9 @@ 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 +790,78 @@ 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 +1874,7 @@ 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)
@@ -1809,20 +1883,19 @@ 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;
@@ -1831,14 +1904,15 @@ int of_update_property(struct device_node *np, struct property *newprop)
 	if (rc)
 		return rc;
 
+	/* At early boot, bail out and defer setup to of_init() */
+	if (!of_kset)
+		return 0;
+
 	/* Update the sysfs attribute */
 	if (oldprop)
 		sysfs_remove_bin_file(&np->kobj, &oldprop->attr);
 	__of_add_property_sysfs(np, newprop);
 
-	if (!found)
-		return -ENODEV;
-
 	return 0;
 }
 
@@ -1887,9 +1961,9 @@ int of_attach_node(struct device_node *np)
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
 	np->sibling = np->parent->child;
-	np->allnext = of_allnodes;
+	np->allnext = np->parent->allnext;
+	np->parent->allnext = np;
 	np->parent->child = np;
-	of_allnodes = np;
 	of_node_clear_flag(np, OF_DETACHED);
 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
@@ -2040,8 +2114,8 @@ void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
  * @np:		Pointer to the given device_node
  * @stem:	Alias stem of the given device_node
  *
- * The function travels the lookup table to get alias id for the given
- * device_node and alias stem.  It returns the alias id if find it.
+ * The function travels the lookup table to get the alias id for the given
+ * device_node and alias stem.  It returns the alias id if found.
  */
 int of_alias_get_id(struct device_node *np, const char *stem)
 {
@@ -2196,64 +2270,65 @@ struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
 					struct device_node *prev)
 {
 	struct device_node *endpoint;
-	struct device_node *port = NULL;
+	struct device_node *port;
 
 	if (!parent)
 		return NULL;
 
+	/*
+	 * Start by locating the port node. If no previous endpoint is specified
+	 * search for the first port node, otherwise get the previous endpoint
+	 * parent port node.
+	 */
 	if (!prev) {
 		struct device_node *node;
-		/*
-		 * It's the first call, we have to find a port subnode
-		 * within this node or within an optional 'ports' node.
-		 */
+
 		node = of_get_child_by_name(parent, "ports");
 		if (node)
 			parent = node;
 
 		port = of_get_child_by_name(parent, "port");
-
-		if (port) {
-			/* Found a port, get an endpoint. */
-			endpoint = of_get_next_child(port, NULL);
-			of_node_put(port);
-		} else {
-			endpoint = NULL;
-		}
-
-		if (!endpoint)
-			pr_err("%s(): no endpoint nodes specified for %s\n",
-			       __func__, parent->full_name);
 		of_node_put(node);
 
-		return endpoint;
-	}
-
-	port = of_get_parent(prev);
-	if (WARN_ONCE(!port, "%s(): endpoint %s has no parent node\n",
-		      __func__, prev->full_name))
-		return NULL;
+		if (!port) {
+			pr_err("%s(): no port node found in %s\n",
+			       __func__, parent->full_name);
+			return NULL;
+		}
+	} else {
+		port = of_get_parent(prev);
+		if (WARN_ONCE(!port, "%s(): endpoint %s has no parent node\n",
+			      __func__, prev->full_name))
+			return NULL;
 
-	/* Avoid dropping prev node refcount to 0. */
-	of_node_get(prev);
-	endpoint = of_get_next_child(port, prev);
-	if (endpoint) {
-		of_node_put(port);
-		return endpoint;
+		/*
+		 * Avoid dropping prev node refcount to 0 when getting the next
+		 * child below.
+		 */
+		of_node_get(prev);
 	}
 
-	/* No more endpoints under this port, try the next one. */
-	do {
-		port = of_get_next_child(parent, port);
-		if (!port)
-			return NULL;
-	} while (of_node_cmp(port->name, "port"));
+	while (1) {
+		/*
+		 * Now that we have a port node, get the next endpoint by
+		 * getting the next child. If the previous endpoint is NULL this
+		 * will return the first child.
+		 */
+		endpoint = of_get_next_child(port, prev);
+		if (endpoint) {
+			of_node_put(port);
+			return endpoint;
+		}
 
-	/* Pick up the first endpoint in this port. */
-	endpoint = of_get_next_child(port, NULL);
-	of_node_put(port);
+		/* No more endpoints under this port, try the next one. */
+		prev = NULL;
 
-	return endpoint;
+		do {
+			port = of_get_next_child(parent, port);
+			if (!port)
+				return NULL;
+		} while (of_node_cmp(port->name, "port"));
+	}
 }
 EXPORT_SYMBOL(of_graph_get_next_endpoint);