of/selftest: Add self tests for manipulation of properties

Adds a few simple test cases to ensure that addition, update and removal
of device tree node properties works correctly.
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Cc: Pantelis Antoniou <panto@antoniou-consulting.com>

drivers/of/selftest.c

@@ -30,6 +30,67 @@ static struct selftest_results {
 	} \
 }
 
+static void __init of_selftest_dynamic(void)
+{
+	struct device_node *np;
+	struct property *prop;
+
+	np = of_find_node_by_path("/testcase-data");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	/* Array of 4 properties for the purpose of testing */
+	prop = kzalloc(sizeof(*prop) * 4, GFP_KERNEL);
+	if (!prop) {
+		selftest(0, "kzalloc() failed\n");
+		return;
+	}
+
+	/* Add a new property - should pass*/
+	prop->name = "new-property";
+	prop->value = "new-property-data";
+	prop->length = strlen(prop->value);
+	selftest(of_add_property(np, prop) == 0, "Adding a new property failed\n");
+
+	/* Try to add an existing property - should fail */
+	prop++;
+	prop->name = "new-property";
+	prop->value = "new-property-data-should-fail";
+	prop->length = strlen(prop->value);
+	selftest(of_add_property(np, prop) != 0,
+		 "Adding an existing property should have failed\n");
+
+	/* Try to modify an existing property - should pass */
+	prop->value = "modify-property-data-should-pass";
+	prop->length = strlen(prop->value);
+	selftest(of_update_property(np, prop) == 0,
+		 "Updating an existing property should have passed\n");
+
+	/* Try to modify non-existent property - should pass*/
+	prop++;
+	prop->name = "modify-property";
+	prop->value = "modify-missing-property-data-should-pass";
+	prop->length = strlen(prop->value);
+	selftest(of_update_property(np, prop) == 0,
+		 "Updating a missing property should have passed\n");
+
+	/* Remove property - should pass */
+	selftest(of_remove_property(np, prop) == 0,
+		 "Removing a property should have passed\n");
+
+	/* Adding very large property - should pass */
+	prop++;
+	prop->name = "large-property-PAGE_SIZEx8";
+	prop->length = PAGE_SIZE * 8;
+	prop->value = kzalloc(prop->length, GFP_KERNEL);
+	selftest(prop->value != NULL, "Unable to allocate large buffer\n");
+	if (prop->value)
+		selftest(of_add_property(np, prop) == 0,
+			 "Adding a large property should have passed\n");
+}
+
 static void __init of_selftest_parse_phandle_with_args(void)
 {
 	struct device_node *np;
@@ -378,6 +439,7 @@ static int __init of_selftest(void)
 	of_node_put(np);
 
 	pr_info("start of selftest - you will see error messages\n");
+	of_selftest_dynamic();
 	of_selftest_parse_phandle_with_args();
 	of_selftest_property_match_string();
 	of_selftest_parse_interrupts();