of: Add a testcase for of_find_node_by_path()

Add a testcase for the find_node_by_path() function to make sure it
handles all the valid scenarios.
Signed-off-by: NGrant Likely <grant.likely@linaro.org>

drivers/of/selftest.c

@@ -31,6 +31,51 @@ static struct selftest_results {
 	} \
 }
 
+static void __init of_selftest_find_node_by_name(void)
+{
+	struct device_node *np;
+
+	np = of_find_node_by_path("/testcase-data");
+	selftest(np && !strcmp("/testcase-data", np->full_name),
+		"find /testcase-data failed\n");
+	of_node_put(np);
+
+	/* Test if trailing '/' works */
+	np = of_find_node_by_path("/testcase-data/");
+	selftest(!np, "trailing '/' on /testcase-data/ should fail\n");
+
+	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+	selftest(np && !strcmp("/testcase-data/phandle-tests/consumer-a", np->full_name),
+		"find /testcase-data/phandle-tests/consumer-a failed\n");
+	of_node_put(np);
+
+	np = of_find_node_by_path("testcase-alias");
+	selftest(np && !strcmp("/testcase-data", np->full_name),
+		"find testcase-alias failed\n");
+	of_node_put(np);
+
+	/* Test if trailing '/' works on aliases */
+	np = of_find_node_by_path("testcase-alias/");
+	selftest(!np, "trailing '/' on testcase-alias/ should fail\n");
+
+	np = of_find_node_by_path("testcase-alias/phandle-tests/consumer-a");
+	selftest(np && !strcmp("/testcase-data/phandle-tests/consumer-a", np->full_name),
+		"find testcase-alias/phandle-tests/consumer-a failed\n");
+	of_node_put(np);
+
+	np = of_find_node_by_path("/testcase-data/missing-path");
+	selftest(!np, "non-existent path returned node %s\n", np->full_name);
+	of_node_put(np);
+
+	np = of_find_node_by_path("missing-alias");
+	selftest(!np, "non-existent alias returned node %s\n", np->full_name);
+	of_node_put(np);
+
+	np = of_find_node_by_path("testcase-alias/missing-path");
+	selftest(!np, "non-existent alias with relative path returned node %s\n", np->full_name);
+	of_node_put(np);
+}
+
 static void __init of_selftest_dynamic(void)
 {
 	struct device_node *np;
@@ -484,6 +529,7 @@ static int __init of_selftest(void)
 	of_node_put(np);
 
 	pr_info("start of selftest - you will see error messages\n");
+	of_selftest_find_node_by_name();
 	of_selftest_dynamic();
 	of_selftest_parse_phandle_with_args();
 	of_selftest_property_match_string();

drivers/of/testcase-data/tests-phandle.dtsi

 
 / {
-	testcase-data {
+	aliases {
+		testcase-alias = &testcase;
+	};
+
+	testcase: testcase-data {
 		security-password = "password";
 		duplicate-name = "duplicate";
 		duplicate-name { };