From d807358c867e6c2ce845161c70097719e754c33a Mon Sep 17 00:00:00 2001
From: cwz <cwz@rock-chips.com>
Date: Tue, 17 Mar 2015 16:59:02 +0800
Subject: [PATCH] libfdt: add api fdt_node_offset_by_phandle_node() find node
 with phandle and start node.

Change-Id: I3d7c710367005510ed936e75863f9d3685cb4bc5
Signed-off-by: Mark Yao <mark.yao@rock-chips.com>
Signed-off-by: cwz <cwz@rock-chips.com>
---
 lib/libfdt/fdt_ro.c | 23 +++++++++++++++++++++++
 lib/libfdt/libfdt.h | 21 +++++++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/lib/libfdt/fdt_ro.c b/lib/libfdt/fdt_ro.c
index 9994d17e56..49c3cddc6f 100755
--- a/lib/libfdt/fdt_ro.c
+++ b/lib/libfdt/fdt_ro.c
@@ -526,6 +526,29 @@ int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle)
 	return offset; /* error from fdt_next_node() */
 }
 
+int fdt_node_offset_by_phandle_node(const void *fdt, int node, uint32_t phandle)
+{
+	int offset;
+
+	if ((phandle == 0) || (phandle == -1) || (node < 0))
+		return -FDT_ERR_BADPHANDLE;
+
+	FDT_CHECK_HEADER(fdt);
+
+	offset = node;
+	if (fdt_get_phandle(fdt, offset) == phandle)
+		return offset;
+
+	for (offset = fdt_next_node(fdt, offset, NULL);
+	     offset >= 0;
+	     offset = fdt_next_node(fdt, offset, NULL)) {
+		if (fdt_get_phandle(fdt, offset) == phandle)
+			return offset;
+	}
+
+	return offset; /* error from fdt_next_node() */
+}
+
 int fdt_stringlist_contains(const char *strlist, int listlen, const char *str)
 {
 	int len = strlen(str);
diff --git a/lib/libfdt/libfdt.h b/lib/libfdt/libfdt.h
index 210bc855e9..cb533f4275 100644
--- a/lib/libfdt/libfdt.h
+++ b/lib/libfdt/libfdt.h
@@ -2166,6 +2166,27 @@ int fdt_next_region(const void *fdt,
 int fdt_add_alias_regions(const void *fdt, struct fdt_region *region, int count,
 			  int max_regions, struct fdt_region_state *info);
 int fdt_device_is_available(const void *blob, int node);
+/**
+ * fdt_node_offset_by_phandle_node - find the node with a given phandle and node
+ * @fdt: pointer to the device tree blob
+ * @phandle: phandle value
+ * @node: start node value
+ *
+ * fdt_node_offset_by_phandle_node() returns the offset of the node
+ * which has the given phandle value.  If there is more than one node
+ * in the tree with the given phandle (an invalid tree), results are
+ * undefined.
+ *
+ * returns:
+ *	structure block offset of the located node (>= 0), on success
+ *	-FDT_ERR_NOTFOUND, no node with that phandle exists
+ *	-FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
+ *	-FDT_ERR_BADMAGIC,
+ *	-FDT_ERR_BADVERSION,
+ *	-FDT_ERR_BADSTATE,
+ *	-FDT_ERR_BADSTRUCTURE, standard meanings
+ */
+int fdt_node_offset_by_phandle_node(const void *fdt, int node, uint32_t phandle);
 #endif /* SWIG */
 
 #endif /* _LIBFDT_H */