libfdt: fdt_address_cells() and fdt_size_cells()

Add internal fdt_cells() to avoid copy and paste.  Test error cases and
default values.  Fix typo in fdt_size_cells() documentation comment.

Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

tests/addr_size_cells2.c

@@ -0,0 +1,62 @@
+/*
+ * libfdt - Flat Device Tree manipulation
+ *	Testcase for #address-cells and #size-cells handling
+ * Copyright (C) 2014 David Gibson, <david@gibson.dropbear.id.au>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+
+#include <libfdt.h>
+
+#include "tests.h"
+#include "testdata.h"
+
+static void check_node(const void *fdt, const char *path, int ac, int sc)
+{
+	int offset;
+	int xac, xsc;
+
+	offset = fdt_path_offset(fdt, path);
+	if (offset < 0)
+		FAIL("Couldn't find path %s", path);
+
+	xac = fdt_address_cells(fdt, offset);
+	xsc = fdt_size_cells(fdt, offset);
+
+	if (xac != ac)
+		FAIL("Address cells for %s is %d instead of %d\n",
+		     path, xac, ac);
+	if (xsc != sc)
+		FAIL("Size cells for %s is %d instead of %d\n",
+		     path, xsc, sc);
+}
+
+int main(int argc, char *argv[])
+{
+	void *fdt;
+
+	if (argc != 2)
+		CONFIG("Usage: %s <dtb file>\n", argv[0]);
+
+	test_init(argc, argv);
+	fdt = load_blob(argv[1]);
+
+	check_node(fdt, "/", 2, 2);
+	PASS();
+}