Consolidate of_find_node_by routines

This consolidates the routines of_find_node_by_path, of_find_node_by_name,
of_find_node_by_type and of_find_compatible_device.  Again, the comparison
of strings are done differently by Sparc and PowerPC and also these add
read_locks around the iterations.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: David S. Miller <davem@davemloft.net>

1 files changed, 115 insertions, 0 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 6b6dfcc56522..9377f3bc410a 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -20,6 +20,8 @@
 #include <linux/of.h>
 #include <linux/spinlock.h>
 
+struct device_node *allnodes;
+
 /* use when traversing tree through the allnext, child, sibling,
  * or parent members of struct device_node.
  */
@@ -158,3 +160,116 @@ struct device_node *of_get_next_child(const struct device_node *node,
         return next;
 }
 EXPORT_SYMBOL(of_get_next_child);
+
+/**
+ *      of_find_node_by_path - Find a node matching a full OF path
+ *      @path:  The full path to match
+ *
+ *      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 = allnodes;
+
+        read_lock(&devtree_lock);
+        for (; np; np = np->allnext) {
+                if (np->full_name && (of_node_cmp(np->full_name, path) == 0)
+                    && of_node_get(np))
+                        break;
+        }
+        read_unlock(&devtree_lock);
+        return np;
+}
+EXPORT_SYMBOL(of_find_node_by_path);
+
+/**
+ *      of_find_node_by_name - Find a node by its "name" property
+ *      @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
+ *      @name:  The name string to match against
+ *
+ *      Returns a node pointer with refcount incremented, use
+ *      of_node_put() on it when done.
+ */
+struct device_node *of_find_node_by_name(struct device_node *from,
+        const char *name)
+{
+        struct device_node *np;
+
+        read_lock(&devtree_lock);
+        np = from ? from->allnext : allnodes;
+        for (; np; np = np->allnext)
+                if (np->name && (of_node_cmp(np->name, name) == 0)
+                    && of_node_get(np))
+                        break;
+        of_node_put(from);
+        read_unlock(&devtree_lock);
+        return np;
+}
+EXPORT_SYMBOL(of_find_node_by_name);
+
+/**
+ *      of_find_node_by_type - Find a node by its "device_type" property
+ *      @from:  The node to start searching from, or NULL to start searching
+ *              the entire device tree. 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 from for you.
+ *      @type:  The type string to match against
+ *
+ *      Returns a node pointer with refcount incremented, use
+ *      of_node_put() on it when done.
+ */
+struct device_node *of_find_node_by_type(struct device_node *from,
+        const char *type)
+{
+        struct device_node *np;
+
+        read_lock(&devtree_lock);
+        np = from ? from->allnext : allnodes;
+        for (; np; np = np->allnext)
+                if (np->type && (of_node_cmp(np->type, type) == 0)
+                    && of_node_get(np))
+                        break;
+        of_node_put(from);
+        read_unlock(&devtree_lock);
+        return np;
+}
+EXPORT_SYMBOL(of_find_node_by_type);
+
+/**
+ *      of_find_compatible_node - Find a node based on type and one of the
+ *                                tokens in its "compatible" property
+ *      @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
+ *      @type:          The type string to match "device_type" or NULL to ignore
+ *      @compatible:    The string to match to one of the tokens in the device
+ *                      "compatible" list.
+ *
+ *      Returns a node pointer with refcount incremented, use
+ *      of_node_put() on it when done.
+ */
+struct device_node *of_find_compatible_node(struct device_node *from,
+        const char *type, const char *compatible)
+{
+        struct device_node *np;
+
+        read_lock(&devtree_lock);
+        np = from ? from->allnext : allnodes;
+        for (; np; np = np->allnext) {
+                if (type
+                    && !(np->type && (of_node_cmp(np->type, type) == 0)))
+                        continue;
+                if (of_device_is_compatible(np, compatible) && of_node_get(np))
+                        break;
+        }
+        of_node_put(from);
+        read_unlock(&devtree_lock);
+        return np;
+}
+EXPORT_SYMBOL(of_find_compatible_node);