LXR linux/arch/powerpc/platforms/pseries/of

   1#include <linux/string.h>
   2#include <linux/err.h>
   3#include <linux/slab.h>
   4#include <linux/of.h>
   5
   6#include "of_helpers.h"
   7
   8/**
   9 * pseries_of_derive_parent - basically like dirname(1)
  10 * @path:  the full_name of a node to be added to the tree
  11 *
  12 * Returns the node which should be the parent of the node
  13 * described by path.  E.g., for path = "/foo/bar", returns
  14 * the node with full_name = "/foo".
  15 */
  16struct device_node *pseries_of_derive_parent(const char *path)
  17{
  18        struct device_node *parent;
  19        char *parent_path = "/";
  20        const char *tail;
  21
  22        /* We do not want the trailing '/' character */
  23        tail = kbasename(path) - 1;
  24
  25        /* reject if path is "/" */
  26        if (!strcmp(path, "/"))
  27                return ERR_PTR(-EINVAL);
  28
  29        if (tail > path) {
  30                parent_path = kstrndup(path, tail - path, GFP_KERNEL);
  31                if (!parent_path)
  32                        return ERR_PTR(-ENOMEM);
  33        }
  34        parent = of_find_node_by_path(parent_path);
  35        if (strcmp(parent_path, "/"))
  36                kfree(parent_path);
  37        return parent ? parent : ERR_PTR(-EINVAL);
  38}
  39