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kernel/linux-rt-4.4.41/arch/powerpc/platforms/pseries/of_helpers.c 976 Bytes
5113f6f70   김현기   kernel add
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  #include <linux/string.h>
  #include <linux/err.h>
  #include <linux/slab.h>
  #include <linux/of.h>
  
  #include "of_helpers.h"
  
  /**
   * pseries_of_derive_parent - basically like dirname(1)
   * @path:  the full_name of a node to be added to the tree
   *
   * Returns the node which should be the parent of the node
   * described by path.  E.g., for path = "/foo/bar", returns
   * the node with full_name = "/foo".
   */
  struct device_node *pseries_of_derive_parent(const char *path)
  {
  	struct device_node *parent;
  	char *parent_path = "/";
  	const char *tail;
  
  	/* We do not want the trailing '/' character */
  	tail = kbasename(path) - 1;
  
  	/* reject if path is "/" */
  	if (!strcmp(path, "/"))
  		return ERR_PTR(-EINVAL);
  
  	if (tail > path) {
  		parent_path = kstrndup(path, tail - path, GFP_KERNEL);
  		if (!parent_path)
  			return ERR_PTR(-ENOMEM);
  	}
  	parent = of_find_node_by_path(parent_path);
  	if (strcmp(parent_path, "/"))
  		kfree(parent_path);
  	return parent ? parent : ERR_PTR(-EINVAL);
  }