brcm63xx: add support for registering parallel flash through dtb

[openwrt.git] / target / linux / brcm63xx / patches-3.14 / 003-of-Make-of_find_node_by_path-handle-aliases.patch

diff --git a/target/linux/brcm63xx/patches-3.14/003-of-Make-of_find_node_by_path-handle-aliases.patch b/target/linux/brcm63xx/patches-3.14/003-of-Make-of_find_node_by_path-handle-aliases.patch
new file mode 100644 (file)
index 0000000..9ad0780
--- /dev/null
+++ b/target/linux/brcm63xx/patches-3.14/003-of-Make-of_find_node_by_path-handle-aliases.patch
@@ -0,0 +1,106 @@
+From c22e650e66b862babe9c00bebb20b8029c7b0362 Mon Sep 17 00:00:00 2001
+From: Grant Likely <grant.likely@linaro.org>
+Date: Fri, 14 Mar 2014 17:07:12 +0000
+Subject: [PATCH] of: Make of_find_node_by_path() handle /aliases
+
+Make of_find_node_by_path() handle aliases as prefixes. To make this
+work the name search is refactored to search by path component instead
+of by full string. This should be a more efficient search, and it makes
+it possible to start a search at a subnode of a tree.
+
+Signed-off-by: David Daney <david.daney@cavium.com>
+Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
+[grant.likely: Rework to not require allocating at runtime]
+Acked-by: Rob Herring <robh@kernel.org>
+Signed-off-by: Grant Likely <grant.likely@linaro.org>
+---
+ drivers/of/base.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++-----
+ 1 file changed, 61 insertions(+), 6 deletions(-)
+
+--- a/drivers/of/base.c
++++ b/drivers/of/base.c
+@@ -633,23 +633,78 @@ struct device_node *of_get_child_by_name
+ }
+ 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;