Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 4065 insertions, 0 deletions

diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
new file mode 100644
index 0000000000..f278def7ef
--- /dev/null
+++ b/drivers/of/unittest.c
@@ -0,0 +1,4065 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Self tests for device tree subsystem
+ */
+
+#define pr_fmt(fmt) "### dt-test ### " fmt
+
+#include <linux/memblock.h>
+#include <linux/clk.h>
+#include <linux/dma-direct.h> /* to test phys_to_dma/dma_to_phys */
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/hashtable.h>
+#include <linux/libfdt.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_fdt.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/pci.h>
+#include <linux/kernel.h>
+
+#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
+#include <linux/gpio/driver.h>
+
+#include <linux/bitops.h>
+
+#include "of_private.h"
+
+static struct unittest_results {
+	int passed;
+	int failed;
+} unittest_results;
+
+#define unittest(result, fmt, ...) ({ \
+	bool failed = !(result); \
+	if (failed) { \
+		unittest_results.failed++; \
+		pr_err("FAIL %s():%i " fmt, __func__, __LINE__, ##__VA_ARGS__); \
+	} else { \
+		unittest_results.passed++; \
+		pr_info("pass %s():%i\n", __func__, __LINE__); \
+	} \
+	failed; \
+})
+
+/*
+ * Expected message may have a message level other than KERN_INFO.
+ * Print the expected message only if the current loglevel will allow
+ * the actual message to print.
+ *
+ * Do not use EXPECT_BEGIN(), EXPECT_END(), EXPECT_NOT_BEGIN(), or
+ * EXPECT_NOT_END() to report messages expected to be reported or not
+ * reported by pr_debug().
+ */
+#define EXPECT_BEGIN(level, fmt, ...) \
+	printk(level pr_fmt("EXPECT \\ : ") fmt, ##__VA_ARGS__)
+
+#define EXPECT_END(level, fmt, ...) \
+	printk(level pr_fmt("EXPECT / : ") fmt, ##__VA_ARGS__)
+
+#define EXPECT_NOT_BEGIN(level, fmt, ...) \
+	printk(level pr_fmt("EXPECT_NOT \\ : ") fmt, ##__VA_ARGS__)
+
+#define EXPECT_NOT_END(level, fmt, ...) \
+	printk(level pr_fmt("EXPECT_NOT / : ") fmt, ##__VA_ARGS__)
+
+static void __init of_unittest_find_node_by_name(void)
+{
+	struct device_node *np;
+	const char *options, *name;
+
+	np = of_find_node_by_path("/testcase-data");
+	name = kasprintf(GFP_KERNEL, "%pOF", np);
+	unittest(np && name && !strcmp("/testcase-data", name),
+		"find /testcase-data failed\n");
+	of_node_put(np);
+	kfree(name);
+
+	/* Test if trailing '/' works */
+	np = of_find_node_by_path("/testcase-data/");
+	unittest(!np, "trailing '/' on /testcase-data/ should fail\n");
+
+	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+	name = kasprintf(GFP_KERNEL, "%pOF", np);
+	unittest(np && name && !strcmp("/testcase-data/phandle-tests/consumer-a", name),
+		"find /testcase-data/phandle-tests/consumer-a failed\n");
+	of_node_put(np);
+	kfree(name);
+
+	np = of_find_node_by_path("testcase-alias");
+	name = kasprintf(GFP_KERNEL, "%pOF", np);
+	unittest(np && name && !strcmp("/testcase-data", name),
+		"find testcase-alias failed\n");
+	of_node_put(np);
+	kfree(name);
+
+	/* Test if trailing '/' works on aliases */
+	np = of_find_node_by_path("testcase-alias/");
+	unittest(!np, "trailing '/' on testcase-alias/ should fail\n");
+
+	np = of_find_node_by_path("testcase-alias/phandle-tests/consumer-a");
+	name = kasprintf(GFP_KERNEL, "%pOF", np);
+	unittest(np && name && !strcmp("/testcase-data/phandle-tests/consumer-a", name),
+		"find testcase-alias/phandle-tests/consumer-a failed\n");
+	of_node_put(np);
+	kfree(name);
+
+	np = of_find_node_by_path("/testcase-data/missing-path");
+	unittest(!np, "non-existent path returned node %pOF\n", np);
+	of_node_put(np);
+
+	np = of_find_node_by_path("missing-alias");
+	unittest(!np, "non-existent alias returned node %pOF\n", np);
+	of_node_put(np);
+
+	np = of_find_node_by_path("testcase-alias/missing-path");
+	unittest(!np, "non-existent alias with relative path returned node %pOF\n", np);
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("/testcase-data:testoption", &options);
+	unittest(np && !strcmp("testoption", options),
+		 "option path test failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("/testcase-data:test/option", &options);
+	unittest(np && !strcmp("test/option", options),
+		 "option path test, subcase #1 failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("/testcase-data/testcase-device1:test/option", &options);
+	unittest(np && !strcmp("test/option", options),
+		 "option path test, subcase #2 failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("/testcase-data:testoption", NULL);
+	unittest(np, "NULL option path test failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("testcase-alias:testaliasoption",
+				       &options);
+	unittest(np && !strcmp("testaliasoption", options),
+		 "option alias path test failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("testcase-alias:test/alias/option",
+				       &options);
+	unittest(np && !strcmp("test/alias/option", options),
+		 "option alias path test, subcase #1 failed\n");
+	of_node_put(np);
+
+	np = of_find_node_opts_by_path("testcase-alias:testaliasoption", NULL);
+	unittest(np, "NULL option alias path test failed\n");
+	of_node_put(np);
+
+	options = "testoption";
+	np = of_find_node_opts_by_path("testcase-alias", &options);
+	unittest(np && !options, "option clearing test failed\n");
+	of_node_put(np);
+
+	options = "testoption";
+	np = of_find_node_opts_by_path("/", &options);
+	unittest(np && !options, "option clearing root node test failed\n");
+	of_node_put(np);
+}
+
+static void __init of_unittest_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 = kcalloc(4, sizeof(*prop), GFP_KERNEL);
+	if (!prop) {
+		unittest(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) + 1;
+	unittest(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) + 1;
+	unittest(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) + 1;
+	unittest(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) + 1;
+	unittest(of_update_property(np, prop) == 0,
+		 "Updating a missing property should have passed\n");
+
+	/* Remove property - should pass */
+	unittest(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);
+	unittest(prop->value != NULL, "Unable to allocate large buffer\n");
+	if (prop->value)
+		unittest(of_add_property(np, prop) == 0,
+			 "Adding a large property should have passed\n");
+}
+
+static int __init of_unittest_check_node_linkage(struct device_node *np)
+{
+	struct device_node *child;
+	int count = 0, rc;
+
+	for_each_child_of_node(np, child) {
+		if (child->parent != np) {
+			pr_err("Child node %pOFn links to wrong parent %pOFn\n",
+				 child, np);
+			rc = -EINVAL;
+			goto put_child;
+		}
+
+		rc = of_unittest_check_node_linkage(child);
+		if (rc < 0)
+			goto put_child;
+		count += rc;
+	}
+
+	return count + 1;
+put_child:
+	of_node_put(child);
+	return rc;
+}
+
+static void __init of_unittest_check_tree_linkage(void)
+{
+	struct device_node *np;
+	int allnode_count = 0, child_count;
+
+	if (!of_root)
+		return;
+
+	for_each_of_allnodes(np)
+		allnode_count++;
+	child_count = of_unittest_check_node_linkage(of_root);
+
+	unittest(child_count > 0, "Device node data structure is corrupted\n");
+	unittest(child_count == allnode_count,
+		 "allnodes list size (%i) doesn't match sibling lists size (%i)\n",
+		 allnode_count, child_count);
+	pr_debug("allnodes list size (%i); sibling lists size (%i)\n", allnode_count, child_count);
+}
+
+static void __init of_unittest_printf_one(struct device_node *np, const char *fmt,
+					  const char *expected)
+{
+	unsigned char *buf;
+	int buf_size;
+	int size, i;
+
+	buf_size = strlen(expected) + 10;
+	buf = kmalloc(buf_size, GFP_KERNEL);
+	if (!buf)
+		return;
+
+	/* Baseline; check conversion with a large size limit */
+	memset(buf, 0xff, buf_size);
+	size = snprintf(buf, buf_size - 2, fmt, np);
+
+	/* use strcmp() instead of strncmp() here to be absolutely sure strings match */
+	unittest((strcmp(buf, expected) == 0) && (buf[size+1] == 0xff),
+		"sprintf failed; fmt='%s' expected='%s' rslt='%s'\n",
+		fmt, expected, buf);
+
+	/* Make sure length limits work */
+	size++;
+	for (i = 0; i < 2; i++, size--) {
+		/* Clear the buffer, and make sure it works correctly still */
+		memset(buf, 0xff, buf_size);
+		snprintf(buf, size+1, fmt, np);
+		unittest(strncmp(buf, expected, size) == 0 && (buf[size+1] == 0xff),
+			"snprintf failed; size=%i fmt='%s' expected='%s' rslt='%s'\n",
+			size, fmt, expected, buf);
+	}
+	kfree(buf);
+}
+
+static void __init of_unittest_printf(void)
+{
+	struct device_node *np;
+	const char *full_name = "/testcase-data/platform-tests/test-device@1/dev@100";
+	char phandle_str[16] = "";
+
+	np = of_find_node_by_path(full_name);
+	if (!np) {
+		unittest(np, "testcase data missing\n");
+		return;
+	}
+
+	num_to_str(phandle_str, sizeof(phandle_str), np->phandle, 0);
+
+	of_unittest_printf_one(np, "%pOF",  full_name);
+	of_unittest_printf_one(np, "%pOFf", full_name);
+	of_unittest_printf_one(np, "%pOFn", "dev");
+	of_unittest_printf_one(np, "%2pOFn", "dev");
+	of_unittest_printf_one(np, "%5pOFn", "  dev");
+	of_unittest_printf_one(np, "%pOFnc", "dev:test-sub-device");
+	of_unittest_printf_one(np, "%pOFp", phandle_str);
+	of_unittest_printf_one(np, "%pOFP", "dev@100");
+	of_unittest_printf_one(np, "ABC %pOFP ABC", "ABC dev@100 ABC");
+	of_unittest_printf_one(np, "%10pOFP", "   dev@100");
+	of_unittest_printf_one(np, "%-10pOFP", "dev@100   ");
+	of_unittest_printf_one(of_root, "%pOFP", "/");
+	of_unittest_printf_one(np, "%pOFF", "----");
+	of_unittest_printf_one(np, "%pOFPF", "dev@100:----");
+	of_unittest_printf_one(np, "%pOFPFPc", "dev@100:----:dev@100:test-sub-device");
+	of_unittest_printf_one(np, "%pOFc", "test-sub-device");
+	of_unittest_printf_one(np, "%pOFC",
+			"\"test-sub-device\",\"test-compat2\",\"test-compat3\"");
+}
+
+struct node_hash {
+	struct hlist_node node;
+	struct device_node *np;
+};
+
+static DEFINE_HASHTABLE(phandle_ht, 8);
+static void __init of_unittest_check_phandles(void)
+{
+	struct device_node *np;
+	struct node_hash *nh;
+	struct hlist_node *tmp;
+	int i, dup_count = 0, phandle_count = 0;
+
+	for_each_of_allnodes(np) {
+		if (!np->phandle)
+			continue;
+
+		hash_for_each_possible(phandle_ht, nh, node, np->phandle) {
+			if (nh->np->phandle == np->phandle) {
+				pr_info("Duplicate phandle! %i used by %pOF and %pOF\n",
+					np->phandle, nh->np, np);
+				dup_count++;
+				break;
+			}
+		}
+
+		nh = kzalloc(sizeof(*nh), GFP_KERNEL);
+		if (!nh)
+			return;
+
+		nh->np = np;
+		hash_add(phandle_ht, &nh->node, np->phandle);
+		phandle_count++;
+	}
+	unittest(dup_count == 0, "Found %i duplicates in %i phandles\n",
+		 dup_count, phandle_count);
+
+	/* Clean up */
+	hash_for_each_safe(phandle_ht, i, tmp, nh, node) {
+		hash_del(&nh->node);
+		kfree(nh);
+	}
+}
+
+static void __init of_unittest_parse_phandle_with_args(void)
+{
+	struct device_node *np;
+	struct of_phandle_args args;
+	int i, rc;
+
+	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	rc = of_count_phandle_with_args(np, "phandle-list", "#phandle-cells");
+	unittest(rc == 7, "of_count_phandle_with_args() returned %i, expected 7\n", rc);
+
+	for (i = 0; i < 8; i++) {
+		bool passed = true;
+
+		memset(&args, 0, sizeof(args));
+		rc = of_parse_phandle_with_args(np, "phandle-list",
+						"#phandle-cells", i, &args);
+
+		/* Test the values from tests-phandle.dtsi */
+		switch (i) {
+		case 0:
+			passed &= !rc;
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == (i + 1));
+			break;
+		case 1:
+			passed &= !rc;
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == (i + 1));
+			passed &= (args.args[1] == 0);
+			break;
+		case 2:
+			passed &= (rc == -ENOENT);
+			break;
+		case 3:
+			passed &= !rc;
+			passed &= (args.args_count == 3);
+			passed &= (args.args[0] == (i + 1));
+			passed &= (args.args[1] == 4);
+			passed &= (args.args[2] == 3);
+			break;
+		case 4:
+			passed &= !rc;
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == (i + 1));
+			passed &= (args.args[1] == 100);
+			break;
+		case 5:
+			passed &= !rc;
+			passed &= (args.args_count == 0);
+			break;
+		case 6:
+			passed &= !rc;
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == (i + 1));
+			break;
+		case 7:
+			passed &= (rc == -ENOENT);
+			break;
+		default:
+			passed = false;
+		}
+
+		unittest(passed, "index %i - data error on node %pOF rc=%i\n",
+			 i, args.np, rc);
+
+		if (rc == 0)
+			of_node_put(args.np);
+	}
+
+	/* Check for missing list property */
+	memset(&args, 0, sizeof(args));
+	rc = of_parse_phandle_with_args(np, "phandle-list-missing",
+					"#phandle-cells", 0, &args);
+	unittest(rc == -ENOENT, "expected:%i got:%i\n", -ENOENT, rc);
+	rc = of_count_phandle_with_args(np, "phandle-list-missing",
+					"#phandle-cells");
+	unittest(rc == -ENOENT, "expected:%i got:%i\n", -ENOENT, rc);
+
+	/* Check for missing cells property */
+	memset(&args, 0, sizeof(args));
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: /testcase-data/phandle-tests/consumer-a: could not get #phandle-cells-missing for /testcase-data/phandle-tests/provider1");
+
+	rc = of_parse_phandle_with_args(np, "phandle-list",
+					"#phandle-cells-missing", 0, &args);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: /testcase-data/phandle-tests/consumer-a: could not get #phandle-cells-missing for /testcase-data/phandle-tests/provider1");
+
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: /testcase-data/phandle-tests/consumer-a: could not get #phandle-cells-missing for /testcase-data/phandle-tests/provider1");
+
+	rc = of_count_phandle_with_args(np, "phandle-list",
+					"#phandle-cells-missing");
+
+	EXPECT_END(KERN_INFO,
+		   "OF: /testcase-data/phandle-tests/consumer-a: could not get #phandle-cells-missing for /testcase-data/phandle-tests/provider1");
+
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+
+	/* Check for bad phandle in list */
+	memset(&args, 0, sizeof(args));
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: /testcase-data/phandle-tests/consumer-a: could not find phandle");
+
+	rc = of_parse_phandle_with_args(np, "phandle-list-bad-phandle",
+					"#phandle-cells", 0, &args);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: /testcase-data/phandle-tests/consumer-a: could not find phandle");
+
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: /testcase-data/phandle-tests/consumer-a: could not find phandle");
+
+	rc = of_count_phandle_with_args(np, "phandle-list-bad-phandle",
+					"#phandle-cells");
+
+	EXPECT_END(KERN_INFO,
+		   "OF: /testcase-data/phandle-tests/consumer-a: could not find phandle");
+
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+
+	/* Check for incorrectly formed argument list */
+	memset(&args, 0, sizeof(args));
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: /testcase-data/phandle-tests/consumer-a: #phandle-cells = 3 found 1");
+
+	rc = of_parse_phandle_with_args(np, "phandle-list-bad-args",
+					"#phandle-cells", 1, &args);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: /testcase-data/phandle-tests/consumer-a: #phandle-cells = 3 found 1");
+
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: /testcase-data/phandle-tests/consumer-a: #phandle-cells = 3 found 1");
+
+	rc = of_count_phandle_with_args(np, "phandle-list-bad-args",
+					"#phandle-cells");
+
+	EXPECT_END(KERN_INFO,
+		   "OF: /testcase-data/phandle-tests/consumer-a: #phandle-cells = 3 found 1");
+
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+}
+
+static void __init of_unittest_parse_phandle_with_args_map(void)
+{
+	struct device_node *np, *p[6] = {};
+	struct of_phandle_args args;
+	unsigned int prefs[6];
+	int i, rc;
+
+	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-b");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	p[0] = of_find_node_by_path("/testcase-data/phandle-tests/provider0");
+	p[1] = of_find_node_by_path("/testcase-data/phandle-tests/provider1");
+	p[2] = of_find_node_by_path("/testcase-data/phandle-tests/provider2");
+	p[3] = of_find_node_by_path("/testcase-data/phandle-tests/provider3");
+	p[4] = of_find_node_by_path("/testcase-data/phandle-tests/provider4");
+	p[5] = of_find_node_by_path("/testcase-data/phandle-tests/provider5");
+	for (i = 0; i < ARRAY_SIZE(p); ++i) {
+		if (!p[i]) {
+			pr_err("missing testcase data\n");
+			return;
+		}
+		prefs[i] = kref_read(&p[i]->kobj.kref);
+	}
+
+	rc = of_count_phandle_with_args(np, "phandle-list", "#phandle-cells");
+	unittest(rc == 8, "of_count_phandle_with_args() returned %i, expected 8\n", rc);
+
+	for (i = 0; i < 9; i++) {
+		bool passed = true;
+
+		memset(&args, 0, sizeof(args));
+		rc = of_parse_phandle_with_args_map(np, "phandle-list",
+						    "phandle", i, &args);
+
+		/* Test the values from tests-phandle.dtsi */
+		switch (i) {
+		case 0:
+			passed &= !rc;
+			passed &= (args.np == p[1]);
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == 1);
+			break;
+		case 1:
+			passed &= !rc;
+			passed &= (args.np == p[3]);
+			passed &= (args.args_count == 3);
+			passed &= (args.args[0] == 2);
+			passed &= (args.args[1] == 5);
+			passed &= (args.args[2] == 3);
+			break;
+		case 2:
+			passed &= (rc == -ENOENT);
+			break;
+		case 3:
+			passed &= !rc;
+			passed &= (args.np == p[0]);
+			passed &= (args.args_count == 0);
+			break;
+		case 4:
+			passed &= !rc;
+			passed &= (args.np == p[1]);
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == 3);
+			break;
+		case 5:
+			passed &= !rc;
+			passed &= (args.np == p[0]);
+			passed &= (args.args_count == 0);
+			break;
+		case 6:
+			passed &= !rc;
+			passed &= (args.np == p[2]);
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == 15);
+			passed &= (args.args[1] == 0x20);
+			break;
+		case 7:
+			passed &= !rc;
+			passed &= (args.np == p[3]);
+			passed &= (args.args_count == 3);
+			passed &= (args.args[0] == 2);
+			passed &= (args.args[1] == 5);
+			passed &= (args.args[2] == 3);
+			break;
+		case 8:
+			passed &= (rc == -ENOENT);
+			break;
+		default:
+			passed = false;
+		}
+
+		unittest(passed, "index %i - data error on node %s rc=%i\n",
+			 i, args.np->full_name, rc);
+
+		if (rc == 0)
+			of_node_put(args.np);
+	}
+
+	/* Check for missing list property */
+	memset(&args, 0, sizeof(args));
+	rc = of_parse_phandle_with_args_map(np, "phandle-list-missing",
+					    "phandle", 0, &args);
+	unittest(rc == -ENOENT, "expected:%i got:%i\n", -ENOENT, rc);
+
+	/* Check for missing cells,map,mask property */
+	memset(&args, 0, sizeof(args));
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: /testcase-data/phandle-tests/consumer-b: could not get #phandle-missing-cells for /testcase-data/phandle-tests/provider1");
+
+	rc = of_parse_phandle_with_args_map(np, "phandle-list",
+					    "phandle-missing", 0, &args);
+	EXPECT_END(KERN_INFO,
+		   "OF: /testcase-data/phandle-tests/consumer-b: could not get #phandle-missing-cells for /testcase-data/phandle-tests/provider1");
+
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+
+	/* Check for bad phandle in list */
+	memset(&args, 0, sizeof(args));
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: /testcase-data/phandle-tests/consumer-b: could not find phandle 12345678");
+
+	rc = of_parse_phandle_with_args_map(np, "phandle-list-bad-phandle",
+					    "phandle", 0, &args);
+	EXPECT_END(KERN_INFO,
+		   "OF: /testcase-data/phandle-tests/consumer-b: could not find phandle 12345678");
+
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+
+	/* Check for incorrectly formed argument list */
+	memset(&args, 0, sizeof(args));
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: /testcase-data/phandle-tests/consumer-b: #phandle-cells = 2 found 1");
+
+	rc = of_parse_phandle_with_args_map(np, "phandle-list-bad-args",
+					    "phandle", 1, &args);
+	EXPECT_END(KERN_INFO,
+		   "OF: /testcase-data/phandle-tests/consumer-b: #phandle-cells = 2 found 1");
+
+	unittest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
+
+	for (i = 0; i < ARRAY_SIZE(p); ++i) {
+		unittest(prefs[i] == kref_read(&p[i]->kobj.kref),
+			 "provider%d: expected:%d got:%d\n",
+			 i, prefs[i], kref_read(&p[i]->kobj.kref));
+		of_node_put(p[i]);
+	}
+}
+
+static void __init of_unittest_property_string(void)
+{
+	const char *strings[4];
+	struct device_node *np;
+	int rc;
+
+	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+	if (!np) {
+		pr_err("No testcase data in device tree\n");
+		return;
+	}
+
+	rc = of_property_match_string(np, "phandle-list-names", "first");
+	unittest(rc == 0, "first expected:0 got:%i\n", rc);
+	rc = of_property_match_string(np, "phandle-list-names", "second");
+	unittest(rc == 1, "second expected:1 got:%i\n", rc);
+	rc = of_property_match_string(np, "phandle-list-names", "third");
+	unittest(rc == 2, "third expected:2 got:%i\n", rc);
+	rc = of_property_match_string(np, "phandle-list-names", "fourth");
+	unittest(rc == -ENODATA, "unmatched string; rc=%i\n", rc);
+	rc = of_property_match_string(np, "missing-property", "blah");
+	unittest(rc == -EINVAL, "missing property; rc=%i\n", rc);
+	rc = of_property_match_string(np, "empty-property", "blah");
+	unittest(rc == -ENODATA, "empty property; rc=%i\n", rc);
+	rc = of_property_match_string(np, "unterminated-string", "blah");
+	unittest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc);
+
+	/* of_property_count_strings() tests */
+	rc = of_property_count_strings(np, "string-property");
+	unittest(rc == 1, "Incorrect string count; rc=%i\n", rc);
+	rc = of_property_count_strings(np, "phandle-list-names");
+	unittest(rc == 3, "Incorrect string count; rc=%i\n", rc);
+	rc = of_property_count_strings(np, "unterminated-string");
+	unittest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc);
+	rc = of_property_count_strings(np, "unterminated-string-list");
+	unittest(rc == -EILSEQ, "unterminated string array; rc=%i\n", rc);
+
+	/* of_property_read_string_index() tests */
+	rc = of_property_read_string_index(np, "string-property", 0, strings);
+	unittest(rc == 0 && !strcmp(strings[0], "foobar"), "of_property_read_string_index() failure; rc=%i\n", rc);
+	strings[0] = NULL;
+	rc = of_property_read_string_index(np, "string-property", 1, strings);
+	unittest(rc == -ENODATA && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc);
+	rc = of_property_read_string_index(np, "phandle-list-names", 0, strings);
+	unittest(rc == 0 && !strcmp(strings[0], "first"), "of_property_read_string_index() failure; rc=%i\n", rc);
+	rc = of_property_read_string_index(np, "phandle-list-names", 1, strings);
+	unittest(rc == 0 && !strcmp(strings[0], "second"), "of_property_read_string_index() failure; rc=%i\n", rc);
+	rc = of_property_read_string_index(np, "phandle-list-names", 2, strings);
+	unittest(rc == 0 && !strcmp(strings[0], "third"), "of_property_read_string_index() failure; rc=%i\n", rc);
+	strings[0] = NULL;
+	rc = of_property_read_string_index(np, "phandle-list-names", 3, strings);
+	unittest(rc == -ENODATA && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc);
+	strings[0] = NULL;
+	rc = of_property_read_string_index(np, "unterminated-string", 0, strings);
+	unittest(rc == -EILSEQ && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc);
+	rc = of_property_read_string_index(np, "unterminated-string-list", 0, strings);
+	unittest(rc == 0 && !strcmp(strings[0], "first"), "of_property_read_string_index() failure; rc=%i\n", rc);
+	strings[0] = NULL;
+	rc = of_property_read_string_index(np, "unterminated-string-list", 2, strings); /* should fail */
+	unittest(rc == -EILSEQ && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc);
+	strings[1] = NULL;
+
+	/* of_property_read_string_array() tests */
+	rc = of_property_read_string_array(np, "string-property", strings, 4);
+	unittest(rc == 1, "Incorrect string count; rc=%i\n", rc);
+	rc = of_property_read_string_array(np, "phandle-list-names", strings, 4);
+	unittest(rc == 3, "Incorrect string count; rc=%i\n", rc);
+	rc = of_property_read_string_array(np, "unterminated-string", strings, 4);
+	unittest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc);
+	/* -- An incorrectly formed string should cause a failure */
+	rc = of_property_read_string_array(np, "unterminated-string-list", strings, 4);
+	unittest(rc == -EILSEQ, "unterminated string array; rc=%i\n", rc);
+	/* -- parsing the correctly formed strings should still work: */
+	strings[2] = NULL;
+	rc = of_property_read_string_array(np, "unterminated-string-list", strings, 2);
+	unittest(rc == 2 && strings[2] == NULL, "of_property_read_string_array() failure; rc=%i\n", rc);
+	strings[1] = NULL;
+	rc = of_property_read_string_array(np, "phandle-list-names", strings, 1);
+	unittest(rc == 1 && strings[1] == NULL, "Overwrote end of string array; rc=%i, str='%s'\n", rc, strings[1]);
+}
+
+#define propcmp(p1, p2) (((p1)->length == (p2)->length) && \
+			(p1)->value && (p2)->value && \
+			!memcmp((p1)->value, (p2)->value, (p1)->length) && \
+			!strcmp((p1)->name, (p2)->name))
+static void __init of_unittest_property_copy(void)
+{
+#ifdef CONFIG_OF_DYNAMIC
+	struct property p1 = { .name = "p1", .length = 0, .value = "" };
+	struct property p2 = { .name = "p2", .length = 5, .value = "abcd" };
+	struct property *new;
+
+	new = __of_prop_dup(&p1, GFP_KERNEL);
+	unittest(new && propcmp(&p1, new), "empty property didn't copy correctly\n");
+	kfree(new->value);
+	kfree(new->name);
+	kfree(new);
+
+	new = __of_prop_dup(&p2, GFP_KERNEL);
+	unittest(new && propcmp(&p2, new), "non-empty property didn't copy correctly\n");
+	kfree(new->value);
+	kfree(new->name);
+	kfree(new);
+#endif
+}
+
+static void __init of_unittest_changeset(void)
+{
+#ifdef CONFIG_OF_DYNAMIC
+	int ret;
+	struct property *ppadd, padd = { .name = "prop-add", .length = 1, .value = "" };
+	struct property *ppname_n1,  pname_n1  = { .name = "name", .length = 3, .value = "n1"  };
+	struct property *ppname_n2,  pname_n2  = { .name = "name", .length = 3, .value = "n2"  };
+	struct property *ppname_n21, pname_n21 = { .name = "name", .length = 3, .value = "n21" };
+	struct property *ppupdate, pupdate = { .name = "prop-update", .length = 5, .value = "abcd" };
+	struct property *ppremove;
+	struct device_node *n1, *n2, *n21, *n22, *nchangeset, *nremove, *parent, *np;
+	static const char * const str_array[] = { "str1", "str2", "str3" };
+	const u32 u32_array[] = { 1, 2, 3 };
+	struct of_changeset chgset;
+	const char *propstr = NULL;
+
+	n1 = __of_node_dup(NULL, "n1");
+	unittest(n1, "testcase setup failure\n");
+
+	n2 = __of_node_dup(NULL, "n2");
+	unittest(n2, "testcase setup failure\n");
+
+	n21 = __of_node_dup(NULL, "n21");
+	unittest(n21, "testcase setup failure %p\n", n21);
+
+	nchangeset = of_find_node_by_path("/testcase-data/changeset");
+	nremove = of_get_child_by_name(nchangeset, "node-remove");
+	unittest(nremove, "testcase setup failure\n");
+
+	ppadd = __of_prop_dup(&padd, GFP_KERNEL);
+	unittest(ppadd, "testcase setup failure\n");
+
+	ppname_n1  = __of_prop_dup(&pname_n1, GFP_KERNEL);
+	unittest(ppname_n1, "testcase setup failure\n");
+
+	ppname_n2  = __of_prop_dup(&pname_n2, GFP_KERNEL);
+	unittest(ppname_n2, "testcase setup failure\n");
+
+	ppname_n21 = __of_prop_dup(&pname_n21, GFP_KERNEL);
+	unittest(ppname_n21, "testcase setup failure\n");
+
+	ppupdate = __of_prop_dup(&pupdate, GFP_KERNEL);
+	unittest(ppupdate, "testcase setup failure\n");
+
+	parent = nchangeset;
+	n1->parent = parent;
+	n2->parent = parent;
+	n21->parent = n2;
+
+	ppremove = of_find_property(parent, "prop-remove", NULL);
+	unittest(ppremove, "failed to find removal prop");
+
+	of_changeset_init(&chgset);
+
+	unittest(!of_changeset_attach_node(&chgset, n1), "fail attach n1\n");
+	unittest(!of_changeset_add_property(&chgset, n1, ppname_n1), "fail add prop name\n");
+
+	unittest(!of_changeset_attach_node(&chgset, n2), "fail attach n2\n");
+	unittest(!of_changeset_add_property(&chgset, n2, ppname_n2), "fail add prop name\n");
+
+	unittest(!of_changeset_detach_node(&chgset, nremove), "fail remove node\n");
+	unittest(!of_changeset_add_property(&chgset, n21, ppname_n21), "fail add prop name\n");
+
+	unittest(!of_changeset_attach_node(&chgset, n21), "fail attach n21\n");
+
+	unittest(!of_changeset_add_property(&chgset, parent, ppadd), "fail add prop prop-add\n");
+	unittest(!of_changeset_update_property(&chgset, parent, ppupdate), "fail update prop\n");
+	unittest(!of_changeset_remove_property(&chgset, parent, ppremove), "fail remove prop\n");
+	n22 = of_changeset_create_node(&chgset, n2, "n22");
+	unittest(n22, "fail create n22\n");
+	unittest(!of_changeset_add_prop_string(&chgset, n22, "prop-str", "abcd"),
+		 "fail add prop prop-str");
+	unittest(!of_changeset_add_prop_string_array(&chgset, n22, "prop-str-array",
+						     (const char **)str_array,
+						     ARRAY_SIZE(str_array)),
+		 "fail add prop prop-str-array");
+	unittest(!of_changeset_add_prop_u32_array(&chgset, n22, "prop-u32-array",
+						  u32_array, ARRAY_SIZE(u32_array)),
+		 "fail add prop prop-u32-array");
+
+	unittest(!of_changeset_apply(&chgset), "apply failed\n");
+
+	of_node_put(nchangeset);
+
+	/* Make sure node names are constructed correctly */
+	unittest((np = of_find_node_by_path("/testcase-data/changeset/n2/n21")),
+		 "'%pOF' not added\n", n21);
+	of_node_put(np);
+	unittest((np = of_find_node_by_path("/testcase-data/changeset/n2/n22")),
+		 "'%pOF' not added\n", n22);
+	of_node_put(np);
+
+	unittest(!of_changeset_revert(&chgset), "revert failed\n");
+
+	unittest(!of_find_node_by_path("/testcase-data/changeset/n2/n21"),
+		 "'%pOF' still present after revert\n", n21);
+
+	ppremove = of_find_property(parent, "prop-remove", NULL);
+	unittest(ppremove, "failed to find removed prop after revert\n");
+
+	ret = of_property_read_string(parent, "prop-update", &propstr);
+	unittest(!ret, "failed to find updated prop after revert\n");
+	if (!ret)
+		unittest(strcmp(propstr, "hello") == 0, "original value not in updated property after revert");
+
+	of_changeset_destroy(&chgset);
+
+	of_node_put(n1);
+	of_node_put(n2);
+	of_node_put(n21);
+	of_node_put(n22);
+#endif
+}
+
+static void __init of_unittest_dma_get_max_cpu_address(void)
+{
+	struct device_node *np;
+	phys_addr_t cpu_addr;
+
+	if (!IS_ENABLED(CONFIG_OF_ADDRESS))
+		return;
+
+	np = of_find_node_by_path("/testcase-data/address-tests");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	cpu_addr = of_dma_get_max_cpu_address(np);
+	unittest(cpu_addr == 0x4fffffff,
+		 "of_dma_get_max_cpu_address: wrong CPU addr %pad (expecting %x)\n",
+		 &cpu_addr, 0x4fffffff);
+}
+
+static void __init of_unittest_dma_ranges_one(const char *path,
+		u64 expect_dma_addr, u64 expect_paddr)
+{
+#ifdef CONFIG_HAS_DMA
+	struct device_node *np;
+	const struct bus_dma_region *map = NULL;
+	int rc;
+
+	np = of_find_node_by_path(path);
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	rc = of_dma_get_range(np, &map);
+
+	unittest(!rc, "of_dma_get_range failed on node %pOF rc=%i\n", np, rc);
+
+	if (!rc) {
+		phys_addr_t	paddr;
+		dma_addr_t	dma_addr;
+		struct device	*dev_bogus;
+
+		dev_bogus = kzalloc(sizeof(struct device), GFP_KERNEL);
+		if (!dev_bogus) {
+			unittest(0, "kzalloc() failed\n");
+			kfree(map);
+			return;
+		}
+
+		dev_bogus->dma_range_map = map;
+		paddr = dma_to_phys(dev_bogus, expect_dma_addr);
+		dma_addr = phys_to_dma(dev_bogus, expect_paddr);
+
+		unittest(paddr == expect_paddr,
+			 "of_dma_get_range: wrong phys addr %pap (expecting %llx) on node %pOF\n",
+			 &paddr, expect_paddr, np);
+		unittest(dma_addr == expect_dma_addr,
+			 "of_dma_get_range: wrong DMA addr %pad (expecting %llx) on node %pOF\n",
+			 &dma_addr, expect_dma_addr, np);
+
+		kfree(map);
+		kfree(dev_bogus);
+	}
+	of_node_put(np);
+#endif
+}
+
+static void __init of_unittest_parse_dma_ranges(void)
+{
+	of_unittest_dma_ranges_one("/testcase-data/address-tests/device@70000000",
+		0x0, 0x20000000);
+	if (IS_ENABLED(CONFIG_ARCH_DMA_ADDR_T_64BIT))
+		of_unittest_dma_ranges_one("/testcase-data/address-tests/bus@80000000/device@1000",
+			0x100000000, 0x20000000);
+	of_unittest_dma_ranges_one("/testcase-data/address-tests/pci@90000000",
+		0x80000000, 0x20000000);
+}
+
+static void __init of_unittest_pci_dma_ranges(void)
+{
+	struct device_node *np;
+	struct of_pci_range range;
+	struct of_pci_range_parser parser;
+	int i = 0;
+
+	if (!IS_ENABLED(CONFIG_PCI))
+		return;
+
+	np = of_find_node_by_path("/testcase-data/address-tests/pci@90000000");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	if (of_pci_dma_range_parser_init(&parser, np)) {
+		pr_err("missing dma-ranges property\n");
+		return;
+	}
+
+	/*
+	 * Get the dma-ranges from the device tree
+	 */
+	for_each_of_pci_range(&parser, &range) {
+		if (!i) {
+			unittest(range.size == 0x10000000,
+				 "for_each_of_pci_range wrong size on node %pOF size=%llx\n",
+				 np, range.size);
+			unittest(range.cpu_addr == 0x20000000,
+				 "for_each_of_pci_range wrong CPU addr (%llx) on node %pOF",
+				 range.cpu_addr, np);
+			unittest(range.pci_addr == 0x80000000,
+				 "for_each_of_pci_range wrong DMA addr (%llx) on node %pOF",
+				 range.pci_addr, np);
+		} else {
+			unittest(range.size == 0x10000000,
+				 "for_each_of_pci_range wrong size on node %pOF size=%llx\n",
+				 np, range.size);
+			unittest(range.cpu_addr == 0x40000000,
+				 "for_each_of_pci_range wrong CPU addr (%llx) on node %pOF",
+				 range.cpu_addr, np);
+			unittest(range.pci_addr == 0xc0000000,
+				 "for_each_of_pci_range wrong DMA addr (%llx) on node %pOF",
+				 range.pci_addr, np);
+		}
+		i++;
+	}
+
+	of_node_put(np);
+}
+
+static void __init of_unittest_bus_ranges(void)
+{
+	struct device_node *np;
+	struct of_range range;
+	struct of_range_parser parser;
+	struct resource res;
+	int ret, count, i = 0;
+
+	np = of_find_node_by_path("/testcase-data/address-tests");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	if (of_range_parser_init(&parser, np)) {
+		pr_err("missing ranges property\n");
+		return;
+	}
+
+	ret = of_range_to_resource(np, 1, &res);
+	unittest(!ret, "of_range_to_resource returned error (%d) node %pOF\n",
+		ret, np);
+	unittest(resource_type(&res) == IORESOURCE_MEM,
+		"of_range_to_resource wrong resource type on node %pOF res=%pR\n",
+		np, &res);
+	unittest(res.start == 0xd0000000,
+		"of_range_to_resource wrong resource start address on node %pOF res=%pR\n",
+		np, &res);
+	unittest(resource_size(&res) == 0x20000000,
+		"of_range_to_resource wrong resource start address on node %pOF res=%pR\n",
+		np, &res);
+
+	count = of_range_count(&parser);
+	unittest(count == 2,
+		"of_range_count wrong size on node %pOF count=%d\n",
+		np, count);
+
+	/*
+	 * Get the "ranges" from the device tree
+	 */
+	for_each_of_range(&parser, &range) {
+		unittest(range.flags == IORESOURCE_MEM,
+			"for_each_of_range wrong flags on node %pOF flags=%x (expected %x)\n",
+			np, range.flags, IORESOURCE_MEM);
+		if (!i) {
+			unittest(range.size == 0x50000000,
+				 "for_each_of_range wrong size on node %pOF size=%llx\n",
+				 np, range.size);
+			unittest(range.cpu_addr == 0x70000000,
+				 "for_each_of_range wrong CPU addr (%llx) on node %pOF",
+				 range.cpu_addr, np);
+			unittest(range.bus_addr == 0x70000000,
+				 "for_each_of_range wrong bus addr (%llx) on node %pOF",
+				 range.pci_addr, np);
+		} else {
+			unittest(range.size == 0x20000000,
+				 "for_each_of_range wrong size on node %pOF size=%llx\n",
+				 np, range.size);
+			unittest(range.cpu_addr == 0xd0000000,
+				 "for_each_of_range wrong CPU addr (%llx) on node %pOF",
+				 range.cpu_addr, np);
+			unittest(range.bus_addr == 0x00000000,
+				 "for_each_of_range wrong bus addr (%llx) on node %pOF",
+				 range.pci_addr, np);
+		}
+		i++;
+	}
+
+	of_node_put(np);
+}
+
+static void __init of_unittest_bus_3cell_ranges(void)
+{
+	struct device_node *np;
+	struct of_range range;
+	struct of_range_parser parser;
+	int i = 0;
+
+	np = of_find_node_by_path("/testcase-data/address-tests/bus@a0000000");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	if (of_range_parser_init(&parser, np)) {
+		pr_err("missing ranges property\n");
+		return;
+	}
+
+	/*
+	 * Get the "ranges" from the device tree
+	 */
+	for_each_of_range(&parser, &range) {
+		if (!i) {
+			unittest(range.flags == 0xf00baa,
+				 "for_each_of_range wrong flags on node %pOF flags=%x\n",
+				 np, range.flags);
+			unittest(range.size == 0x100000,
+				 "for_each_of_range wrong size on node %pOF size=%llx\n",
+				 np, range.size);
+			unittest(range.cpu_addr == 0xa0000000,
+				 "for_each_of_range wrong CPU addr (%llx) on node %pOF",
+				 range.cpu_addr, np);
+			unittest(range.bus_addr == 0x0,
+				 "for_each_of_range wrong bus addr (%llx) on node %pOF",
+				 range.pci_addr, np);
+		} else {
+			unittest(range.flags == 0xf00bee,
+				 "for_each_of_range wrong flags on node %pOF flags=%x\n",
+				 np, range.flags);
+			unittest(range.size == 0x200000,
+				 "for_each_of_range wrong size on node %pOF size=%llx\n",
+				 np, range.size);
+			unittest(range.cpu_addr == 0xb0000000,
+				 "for_each_of_range wrong CPU addr (%llx) on node %pOF",
+				 range.cpu_addr, np);
+			unittest(range.bus_addr == 0x100000000,
+				 "for_each_of_range wrong bus addr (%llx) on node %pOF",
+				 range.pci_addr, np);
+		}
+		i++;
+	}
+
+	of_node_put(np);
+}
+
+static void __init of_unittest_reg(void)
+{
+	struct device_node *np;
+	int ret;
+	u64 addr, size;
+
+	np = of_find_node_by_path("/testcase-data/address-tests/bus@80000000/device@1000");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	ret = of_property_read_reg(np, 0, &addr, &size);
+	unittest(!ret, "of_property_read_reg(%pOF) returned error %d\n",
+		np, ret);
+	unittest(addr == 0x1000, "of_property_read_reg(%pOF) untranslated address (%llx) incorrect\n",
+		np, addr);
+
+	of_node_put(np);
+}
+
+static void __init of_unittest_parse_interrupts(void)
+{
+	struct device_node *np;
+	struct of_phandle_args args;
+	int i, rc;
+
+	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
+		return;
+
+	np = of_find_node_by_path("/testcase-data/interrupts/interrupts0");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	for (i = 0; i < 4; i++) {
+		bool passed = true;
+
+		memset(&args, 0, sizeof(args));
+		rc = of_irq_parse_one(np, i, &args);
+
+		passed &= !rc;
+		passed &= (args.args_count == 1);
+		passed &= (args.args[0] == (i + 1));
+
+		unittest(passed, "index %i - data error on node %pOF rc=%i\n",
+			 i, args.np, rc);
+	}
+	of_node_put(np);
+
+	np = of_find_node_by_path("/testcase-data/interrupts/interrupts1");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	for (i = 0; i < 4; i++) {
+		bool passed = true;
+
+		memset(&args, 0, sizeof(args));
+		rc = of_irq_parse_one(np, i, &args);
+
+		/* Test the values from tests-phandle.dtsi */
+		switch (i) {
+		case 0:
+			passed &= !rc;
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == 9);
+			break;
+		case 1:
+			passed &= !rc;
+			passed &= (args.args_count == 3);
+			passed &= (args.args[0] == 10);
+			passed &= (args.args[1] == 11);
+			passed &= (args.args[2] == 12);
+			break;
+		case 2:
+			passed &= !rc;
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == 13);
+			passed &= (args.args[1] == 14);
+			break;
+		case 3:
+			passed &= !rc;
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == 15);
+			passed &= (args.args[1] == 16);
+			break;
+		default:
+			passed = false;
+		}
+		unittest(passed, "index %i - data error on node %pOF rc=%i\n",
+			 i, args.np, rc);
+	}
+	of_node_put(np);
+}
+
+static void __init of_unittest_parse_interrupts_extended(void)
+{
+	struct device_node *np;
+	struct of_phandle_args args;
+	int i, rc;
+
+	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
+		return;
+
+	np = of_find_node_by_path("/testcase-data/interrupts/interrupts-extended0");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	for (i = 0; i < 7; i++) {
+		bool passed = true;
+
+		memset(&args, 0, sizeof(args));
+		rc = of_irq_parse_one(np, i, &args);
+
+		/* Test the values from tests-phandle.dtsi */
+		switch (i) {
+		case 0:
+			passed &= !rc;
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == 1);
+			break;
+		case 1:
+			passed &= !rc;
+			passed &= (args.args_count == 3);
+			passed &= (args.args[0] == 2);
+			passed &= (args.args[1] == 3);
+			passed &= (args.args[2] == 4);
+			break;
+		case 2:
+			passed &= !rc;
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == 5);
+			passed &= (args.args[1] == 6);
+			break;
+		case 3:
+			passed &= !rc;
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == 9);
+			break;
+		case 4:
+			passed &= !rc;
+			passed &= (args.args_count == 3);
+			passed &= (args.args[0] == 10);
+			passed &= (args.args[1] == 11);
+			passed &= (args.args[2] == 12);
+			break;
+		case 5:
+			passed &= !rc;
+			passed &= (args.args_count == 2);
+			passed &= (args.args[0] == 13);
+			passed &= (args.args[1] == 14);
+			break;
+		case 6:
+			/*
+			 * Tests child node that is missing property
+			 * #address-cells.  See the comments in
+			 * drivers/of/unittest-data/tests-interrupts.dtsi
+			 * nodes intmap1 and interrupts-extended0
+			 */
+			passed &= !rc;
+			passed &= (args.args_count == 1);
+			passed &= (args.args[0] == 15);
+			break;
+		default:
+			passed = false;
+		}
+
+		unittest(passed, "index %i - data error on node %pOF rc=%i\n",
+			 i, args.np, rc);
+	}
+	of_node_put(np);
+}
+
+static const struct of_device_id match_node_table[] = {
+	{ .data = "A", .name = "name0", }, /* Name alone is lowest priority */
+	{ .data = "B", .type = "type1", }, /* followed by type alone */
+
+	{ .data = "Ca", .name = "name2", .type = "type1", }, /* followed by both together */
+	{ .data = "Cb", .name = "name2", }, /* Only match when type doesn't match */
+	{ .data = "Cc", .name = "name2", .type = "type2", },
+
+	{ .data = "E", .compatible = "compat3" },
+	{ .data = "G", .compatible = "compat2", },
+	{ .data = "H", .compatible = "compat2", .name = "name5", },
+	{ .data = "I", .compatible = "compat2", .type = "type1", },
+	{ .data = "J", .compatible = "compat2", .type = "type1", .name = "name8", },
+	{ .data = "K", .compatible = "compat2", .name = "name9", },
+	{}
+};
+
+static struct {
+	const char *path;
+	const char *data;
+} match_node_tests[] = {
+	{ .path = "/testcase-data/match-node/name0", .data = "A", },
+	{ .path = "/testcase-data/match-node/name1", .data = "B", },
+	{ .path = "/testcase-data/match-node/a/name2", .data = "Ca", },
+	{ .path = "/testcase-data/match-node/b/name2", .data = "Cb", },
+	{ .path = "/testcase-data/match-node/c/name2", .data = "Cc", },
+	{ .path = "/testcase-data/match-node/name3", .data = "E", },
+	{ .path = "/testcase-data/match-node/name4", .data = "G", },
+	{ .path = "/testcase-data/match-node/name5", .data = "H", },
+	{ .path = "/testcase-data/match-node/name6", .data = "G", },
+	{ .path = "/testcase-data/match-node/name7", .data = "I", },
+	{ .path = "/testcase-data/match-node/name8", .data = "J", },
+	{ .path = "/testcase-data/match-node/name9", .data = "K", },
+};
+
+static void __init of_unittest_match_node(void)
+{
+	struct device_node *np;
+	const struct of_device_id *match;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(match_node_tests); i++) {
+		np = of_find_node_by_path(match_node_tests[i].path);
+		if (!np) {
+			unittest(0, "missing testcase node %s\n",
+				match_node_tests[i].path);
+			continue;
+		}
+
+		match = of_match_node(match_node_table, np);
+		if (!match) {
+			unittest(0, "%s didn't match anything\n",
+				match_node_tests[i].path);
+			continue;
+		}
+
+		if (strcmp(match->data, match_node_tests[i].data) != 0) {
+			unittest(0, "%s got wrong match. expected %s, got %s\n",
+				match_node_tests[i].path, match_node_tests[i].data,
+				(const char *)match->data);
+			continue;
+		}
+		unittest(1, "passed");
+	}
+}
+
+static struct resource test_bus_res = DEFINE_RES_MEM(0xfffffff8, 2);
+static const struct platform_device_info test_bus_info = {
+	.name = "unittest-bus",
+};
+static void __init of_unittest_platform_populate(void)
+{
+	int irq, rc;
+	struct device_node *np, *child, *grandchild;
+	struct platform_device *pdev, *test_bus;
+	const struct of_device_id match[] = {
+		{ .compatible = "test-device", },
+		{}
+	};
+
+	np = of_find_node_by_path("/testcase-data");
+	of_platform_default_populate(np, NULL, NULL);
+
+	/* Test that a missing irq domain returns -EPROBE_DEFER */
+	np = of_find_node_by_path("/testcase-data/testcase-device1");
+	pdev = of_find_device_by_node(np);
+	unittest(pdev, "device 1 creation failed\n");
+
+	if (!(of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)) {
+		irq = platform_get_irq(pdev, 0);
+		unittest(irq == -EPROBE_DEFER,
+			 "device deferred probe failed - %d\n", irq);
+
+		/* Test that a parsing failure does not return -EPROBE_DEFER */
+		np = of_find_node_by_path("/testcase-data/testcase-device2");
+		pdev = of_find_device_by_node(np);
+		unittest(pdev, "device 2 creation failed\n");
+
+		EXPECT_BEGIN(KERN_INFO,
+			     "platform testcase-data:testcase-device2: error -ENXIO: IRQ index 0 not found");
+
+		irq = platform_get_irq(pdev, 0);
+
+		EXPECT_END(KERN_INFO,
+			   "platform testcase-data:testcase-device2: error -ENXIO: IRQ index 0 not found");
+
+		unittest(irq < 0 && irq != -EPROBE_DEFER,
+			 "device parsing error failed - %d\n", irq);
+	}
+
+	np = of_find_node_by_path("/testcase-data/platform-tests");
+	unittest(np, "No testcase data in device tree\n");
+	if (!np)
+		return;
+
+	test_bus = platform_device_register_full(&test_bus_info);
+	rc = PTR_ERR_OR_ZERO(test_bus);
+	unittest(!rc, "testbus registration failed; rc=%i\n", rc);
+	if (rc) {
+		of_node_put(np);
+		return;
+	}
+	test_bus->dev.of_node = np;
+
+	/*
+	 * Add a dummy resource to the test bus node after it is
+	 * registered to catch problems with un-inserted resources. The
+	 * DT code doesn't insert the resources, and it has caused the
+	 * kernel to oops in the past. This makes sure the same bug
+	 * doesn't crop up again.
+	 */
+	platform_device_add_resources(test_bus, &test_bus_res, 1);
+
+	of_platform_populate(np, match, NULL, &test_bus->dev);
+	for_each_child_of_node(np, child) {
+		for_each_child_of_node(child, grandchild) {
+			pdev = of_find_device_by_node(grandchild);
+			unittest(pdev,
+				 "Could not create device for node '%pOFn'\n",
+				 grandchild);
+			platform_device_put(pdev);
+		}
+	}
+
+	of_platform_depopulate(&test_bus->dev);
+	for_each_child_of_node(np, child) {
+		for_each_child_of_node(child, grandchild)
+			unittest(!of_find_device_by_node(grandchild),
+				 "device didn't get destroyed '%pOFn'\n",
+				 grandchild);
+	}
+
+	platform_device_unregister(test_bus);
+	of_node_put(np);
+}
+
+/**
+ *	update_node_properties - adds the properties
+ *	of np into dup node (present in live tree) and
+ *	updates parent of children of np to dup.
+ *
+ *	@np:	node whose properties are being added to the live tree
+ *	@dup:	node present in live tree to be updated
+ */
+static void update_node_properties(struct device_node *np,
+					struct device_node *dup)
+{
+	struct property *prop;
+	struct property *save_next;
+	struct device_node *child;
+	int ret;
+
+	for_each_child_of_node(np, child)
+		child->parent = dup;
+
+	/*
+	 * "unittest internal error: unable to add testdata property"
+	 *
+	 *    If this message reports a property in node '/__symbols__' then
+	 *    the respective unittest overlay contains a label that has the
+	 *    same name as a label in the live devicetree.  The label will
+	 *    be in the live devicetree only if the devicetree source was
+	 *    compiled with the '-@' option.  If you encounter this error,
+	 *    please consider renaming __all__ of the labels in the unittest
+	 *    overlay dts files with an odd prefix that is unlikely to be
+	 *    used in a real devicetree.
+	 */
+
+	/*
+	 * open code for_each_property_of_node() because of_add_property()
+	 * sets prop->next to NULL
+	 */
+	for (prop = np->properties; prop != NULL; prop = save_next) {
+		save_next = prop->next;
+		ret = of_add_property(dup, prop);
+		if (ret) {
+			if (ret == -EEXIST && !strcmp(prop->name, "name"))
+				continue;
+			pr_err("unittest internal error: unable to add testdata property %pOF/%s",
+			       np, prop->name);
+		}
+	}
+}
+
+/**
+ *	attach_node_and_children - attaches nodes
+ *	and its children to live tree.
+ *	CAUTION: misleading function name - if node @np already exists in
+ *	the live tree then children of @np are *not* attached to the live
+ *	tree.  This works for the current test devicetree nodes because such
+ *	nodes do not have child nodes.
+ *
+ *	@np:	Node to attach to live tree
+ */
+static void attach_node_and_children(struct device_node *np)
+{
+	struct device_node *next, *dup, *child;
+	unsigned long flags;
+	const char *full_name;
+
+	full_name = kasprintf(GFP_KERNEL, "%pOF", np);
+	if (!full_name)
+		return;
+
+	if (!strcmp(full_name, "/__local_fixups__") ||
+	    !strcmp(full_name, "/__fixups__")) {
+		kfree(full_name);
+		return;
+	}
+
+	dup = of_find_node_by_path(full_name);
+	kfree(full_name);
+	if (dup) {
+		update_node_properties(np, dup);
+		return;
+	}
+
+	child = np->child;
+	np->child = NULL;
+
+	mutex_lock(&of_mutex);
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	np->sibling = np->parent->child;
+	np->parent->child = np;
+	of_node_clear_flag(np, OF_DETACHED);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	__of_attach_node_sysfs(np);
+	mutex_unlock(&of_mutex);
+
+	while (child) {
+		next = child->sibling;
+		attach_node_and_children(child);
+		child = next;
+	}
+}
+
+/**
+ *	unittest_data_add - Reads, copies data from
+ *	linked tree and attaches it to the live tree
+ */
+static int __init unittest_data_add(void)
+{
+	void *unittest_data;
+	void *unittest_data_align;
+	struct device_node *unittest_data_node = NULL, *np;
+	/*
+	 * __dtbo_testcases_begin[] and __dtbo_testcases_end[] are magically
+	 * created by cmd_dt_S_dtbo in scripts/Makefile.lib
+	 */
+	extern uint8_t __dtbo_testcases_begin[];
+	extern uint8_t __dtbo_testcases_end[];
+	const int size = __dtbo_testcases_end - __dtbo_testcases_begin;
+	int rc;
+	void *ret;
+
+	if (!size) {
+		pr_warn("%s: testcases is empty\n", __func__);
+		return -ENODATA;
+	}
+
+	/* creating copy */
+	unittest_data = kmalloc(size + FDT_ALIGN_SIZE, GFP_KERNEL);
+	if (!unittest_data)
+		return -ENOMEM;
+
+	unittest_data_align = PTR_ALIGN(unittest_data, FDT_ALIGN_SIZE);
+	memcpy(unittest_data_align, __dtbo_testcases_begin, size);
+
+	ret = of_fdt_unflatten_tree(unittest_data_align, NULL, &unittest_data_node);
+	if (!ret) {
+		pr_warn("%s: unflatten testcases tree failed\n", __func__);
+		kfree(unittest_data);
+		return -ENODATA;
+	}
+	if (!unittest_data_node) {
+		pr_warn("%s: testcases tree is empty\n", __func__);
+		kfree(unittest_data);
+		return -ENODATA;
+	}
+
+	/*
+	 * This lock normally encloses of_resolve_phandles()
+	 */
+	of_overlay_mutex_lock();
+
+	rc = of_resolve_phandles(unittest_data_node);
+	if (rc) {
+		pr_err("%s: Failed to resolve phandles (rc=%i)\n", __func__, rc);
+		of_overlay_mutex_unlock();
+		return -EINVAL;
+	}
+
+	if (!of_root) {
+		of_root = unittest_data_node;
+		for_each_of_allnodes(np)
+			__of_attach_node_sysfs(np);
+		of_aliases = of_find_node_by_path("/aliases");
+		of_chosen = of_find_node_by_path("/chosen");
+		of_overlay_mutex_unlock();
+		return 0;
+	}
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "Duplicate name in testcase-data, renamed to \"duplicate-name#1\"");
+
+	/* attach the sub-tree to live tree */
+	np = unittest_data_node->child;
+	while (np) {
+		struct device_node *next = np->sibling;
+
+		np->parent = of_root;
+		/* this will clear OF_DETACHED in np and children */
+		attach_node_and_children(np);
+		np = next;
+	}
+
+	EXPECT_END(KERN_INFO,
+		   "Duplicate name in testcase-data, renamed to \"duplicate-name#1\"");
+
+	of_overlay_mutex_unlock();
+
+	return 0;
+}
+
+#ifdef CONFIG_OF_OVERLAY
+static int __init overlay_data_apply(const char *overlay_name, int *ovcs_id);
+
+static int unittest_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+
+	if (np == NULL) {
+		dev_err(dev, "No OF data for device\n");
+		return -EINVAL;
+
+	}
+
+	dev_dbg(dev, "%s for node @%pOF\n", __func__, np);
+
+	of_platform_populate(np, NULL, NULL, &pdev->dev);
+
+	return 0;
+}
+
+static void unittest_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+
+	dev_dbg(dev, "%s for node @%pOF\n", __func__, np);
+}
+
+static const struct of_device_id unittest_match[] = {
+	{ .compatible = "unittest", },
+	{},
+};
+
+static struct platform_driver unittest_driver = {
+	.probe			= unittest_probe,
+	.remove_new		= unittest_remove,
+	.driver = {
+		.name		= "unittest",
+		.of_match_table	= unittest_match,
+	},
+};
+
+/* get the platform device instantiated at the path */
+static struct platform_device *of_path_to_platform_device(const char *path)
+{
+	struct device_node *np;
+	struct platform_device *pdev;
+
+	np = of_find_node_by_path(path);
+	if (np == NULL)
+		return NULL;
+
+	pdev = of_find_device_by_node(np);
+	of_node_put(np);
+
+	return pdev;
+}
+
+/* find out if a platform device exists at that path */
+static int of_path_platform_device_exists(const char *path)
+{
+	struct platform_device *pdev;
+
+	pdev = of_path_to_platform_device(path);
+	platform_device_put(pdev);
+	return pdev != NULL;
+}
+
+#ifdef CONFIG_OF_GPIO
+
+struct unittest_gpio_dev {
+	struct gpio_chip chip;
+};
+
+static int unittest_gpio_chip_request_count;
+static int unittest_gpio_probe_count;
+static int unittest_gpio_probe_pass_count;
+
+static int unittest_gpio_chip_request(struct gpio_chip *chip, unsigned int offset)
+{
+	unittest_gpio_chip_request_count++;
+
+	pr_debug("%s(): %s %d %d\n", __func__, chip->label, offset,
+		 unittest_gpio_chip_request_count);
+	return 0;
+}
+
+static int unittest_gpio_probe(struct platform_device *pdev)
+{
+	struct unittest_gpio_dev *devptr;
+	int ret;
+
+	unittest_gpio_probe_count++;
+
+	devptr = kzalloc(sizeof(*devptr), GFP_KERNEL);
+	if (!devptr)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, devptr);
+
+	devptr->chip.fwnode = dev_fwnode(&pdev->dev);
+	devptr->chip.label = "of-unittest-gpio";
+	devptr->chip.base = -1; /* dynamic allocation */
+	devptr->chip.ngpio = 5;
+	devptr->chip.request = unittest_gpio_chip_request;
+
+	ret = gpiochip_add_data(&devptr->chip, NULL);
+
+	unittest(!ret,
+		 "gpiochip_add_data() for node @%pfw failed, ret = %d\n", devptr->chip.fwnode, ret);
+
+	if (!ret)
+		unittest_gpio_probe_pass_count++;
+	return ret;
+}
+
+static void unittest_gpio_remove(struct platform_device *pdev)
+{
+	struct unittest_gpio_dev *devptr = platform_get_drvdata(pdev);
+	struct device *dev = &pdev->dev;
+
+	dev_dbg(dev, "%s for node @%pfw\n", __func__, devptr->chip.fwnode);
+
+	if (devptr->chip.base != -1)
+		gpiochip_remove(&devptr->chip);
+
+	kfree(devptr);
+}
+
+static const struct of_device_id unittest_gpio_id[] = {
+	{ .compatible = "unittest-gpio", },
+	{}
+};
+
+static struct platform_driver unittest_gpio_driver = {
+	.probe	= unittest_gpio_probe,
+	.remove_new = unittest_gpio_remove,
+	.driver	= {
+		.name		= "unittest-gpio",
+		.of_match_table	= unittest_gpio_id,
+	},
+};
+
+static void __init of_unittest_overlay_gpio(void)
+{
+	int chip_request_count;
+	int probe_pass_count;
+	int ret;
+
+	/*
+	 * tests: apply overlays before registering driver
+	 * Similar to installing a driver as a module, the
+	 * driver is registered after applying the overlays.
+	 *
+	 * The overlays are applied by overlay_data_apply()
+	 * instead of of_unittest_apply_overlay() so that they
+	 * will not be tracked.  Thus they will not be removed
+	 * by of_unittest_remove_tracked_overlays().
+	 *
+	 * - apply overlay_gpio_01
+	 * - apply overlay_gpio_02a
+	 * - apply overlay_gpio_02b
+	 * - register driver
+	 *
+	 * register driver will result in
+	 *   - probe and processing gpio hog for overlay_gpio_01
+	 *   - probe for overlay_gpio_02a
+	 *   - processing gpio for overlay_gpio_02b
+	 */
+
+	probe_pass_count = unittest_gpio_probe_pass_count;
+	chip_request_count = unittest_gpio_chip_request_count;
+
+	/*
+	 * overlay_gpio_01 contains gpio node and child gpio hog node
+	 * overlay_gpio_02a contains gpio node
+	 * overlay_gpio_02b contains child gpio hog node
+	 */
+
+	unittest(overlay_data_apply("overlay_gpio_01", NULL),
+		 "Adding overlay 'overlay_gpio_01' failed\n");
+
+	unittest(overlay_data_apply("overlay_gpio_02a", NULL),
+		 "Adding overlay 'overlay_gpio_02a' failed\n");
+
+	unittest(overlay_data_apply("overlay_gpio_02b", NULL),
+		 "Adding overlay 'overlay_gpio_02b' failed\n");
+
+	ret = platform_driver_register(&unittest_gpio_driver);
+	if (unittest(ret == 0, "could not register unittest gpio driver\n"))
+		return;
+
+	unittest(probe_pass_count + 2 == unittest_gpio_probe_pass_count,
+		 "unittest_gpio_probe() failed or not called\n");
+
+	unittest(chip_request_count + 2 == unittest_gpio_chip_request_count,
+		 "unittest_gpio_chip_request() called %d times (expected 1 time)\n",
+		 unittest_gpio_chip_request_count - chip_request_count);
+
+	/*
+	 * tests: apply overlays after registering driver
+	 *
+	 * Similar to a driver built-in to the kernel, the
+	 * driver is registered before applying the overlays.
+	 *
+	 * overlay_gpio_03 contains gpio node and child gpio hog node
+	 *
+	 * - apply overlay_gpio_03
+	 *
+	 * apply overlay will result in
+	 *   - probe and processing gpio hog.
+	 */
+
+	probe_pass_count = unittest_gpio_probe_pass_count;
+	chip_request_count = unittest_gpio_chip_request_count;
+
+	/* overlay_gpio_03 contains gpio node and child gpio hog node */
+
+	unittest(overlay_data_apply("overlay_gpio_03", NULL),
+		 "Adding overlay 'overlay_gpio_03' failed\n");
+
+	unittest(probe_pass_count + 1 == unittest_gpio_probe_pass_count,
+		 "unittest_gpio_probe() failed or not called\n");
+
+	unittest(chip_request_count + 1 == unittest_gpio_chip_request_count,
+		 "unittest_gpio_chip_request() called %d times (expected 1 time)\n",
+		 unittest_gpio_chip_request_count - chip_request_count);
+
+	/*
+	 * overlay_gpio_04a contains gpio node
+	 *
+	 * - apply overlay_gpio_04a
+	 *
+	 * apply the overlay will result in
+	 *   - probe for overlay_gpio_04a
+	 */
+
+	probe_pass_count = unittest_gpio_probe_pass_count;
+	chip_request_count = unittest_gpio_chip_request_count;
+
+	/* overlay_gpio_04a contains gpio node */
+
+	unittest(overlay_data_apply("overlay_gpio_04a", NULL),
+		 "Adding overlay 'overlay_gpio_04a' failed\n");
+
+	unittest(probe_pass_count + 1 == unittest_gpio_probe_pass_count,
+		 "unittest_gpio_probe() failed or not called\n");
+
+	/*
+	 * overlay_gpio_04b contains child gpio hog node
+	 *
+	 * - apply overlay_gpio_04b
+	 *
+	 * apply the overlay will result in
+	 *   - processing gpio for overlay_gpio_04b
+	 */
+
+	/* overlay_gpio_04b contains child gpio hog node */
+
+	unittest(overlay_data_apply("overlay_gpio_04b", NULL),
+		 "Adding overlay 'overlay_gpio_04b' failed\n");
+
+	unittest(chip_request_count + 1 == unittest_gpio_chip_request_count,
+		 "unittest_gpio_chip_request() called %d times (expected 1 time)\n",
+		 unittest_gpio_chip_request_count - chip_request_count);
+}
+
+#else
+
+static void __init of_unittest_overlay_gpio(void)
+{
+	/* skip tests */
+}
+
+#endif
+
+#if IS_BUILTIN(CONFIG_I2C)
+
+/* get the i2c client device instantiated at the path */
+static struct i2c_client *of_path_to_i2c_client(const char *path)
+{
+	struct device_node *np;
+	struct i2c_client *client;
+
+	np = of_find_node_by_path(path);
+	if (np == NULL)
+		return NULL;
+
+	client = of_find_i2c_device_by_node(np);
+	of_node_put(np);
+
+	return client;
+}
+
+/* find out if a i2c client device exists at that path */
+static int of_path_i2c_client_exists(const char *path)
+{
+	struct i2c_client *client;
+
+	client = of_path_to_i2c_client(path);
+	if (client)
+		put_device(&client->dev);
+	return client != NULL;
+}
+#else
+static int of_path_i2c_client_exists(const char *path)
+{
+	return 0;
+}
+#endif
+
+enum overlay_type {
+	PDEV_OVERLAY,
+	I2C_OVERLAY
+};
+
+static int of_path_device_type_exists(const char *path,
+		enum overlay_type ovtype)
+{
+	switch (ovtype) {
+	case PDEV_OVERLAY:
+		return of_path_platform_device_exists(path);
+	case I2C_OVERLAY:
+		return of_path_i2c_client_exists(path);
+	}
+	return 0;
+}
+
+static const char *unittest_path(int nr, enum overlay_type ovtype)
+{
+	const char *base;
+	static char buf[256];
+
+	switch (ovtype) {
+	case PDEV_OVERLAY:
+		base = "/testcase-data/overlay-node/test-bus";
+		break;
+	case I2C_OVERLAY:
+		base = "/testcase-data/overlay-node/test-bus/i2c-test-bus";
+		break;
+	default:
+		buf[0] = '\0';
+		return buf;
+	}
+	snprintf(buf, sizeof(buf) - 1, "%s/test-unittest%d", base, nr);
+	buf[sizeof(buf) - 1] = '\0';
+	return buf;
+}
+
+static int of_unittest_device_exists(int unittest_nr, enum overlay_type ovtype)
+{
+	const char *path;
+
+	path = unittest_path(unittest_nr, ovtype);
+
+	switch (ovtype) {
+	case PDEV_OVERLAY:
+		return of_path_platform_device_exists(path);
+	case I2C_OVERLAY:
+		return of_path_i2c_client_exists(path);
+	}
+	return 0;
+}
+
+static const char *overlay_name_from_nr(int nr)
+{
+	static char buf[256];
+
+	snprintf(buf, sizeof(buf) - 1,
+		"overlay_%d", nr);
+	buf[sizeof(buf) - 1] = '\0';
+
+	return buf;
+}
+
+static const char *bus_path = "/testcase-data/overlay-node/test-bus";
+
+#define MAX_TRACK_OVCS_IDS 256
+
+static int track_ovcs_id[MAX_TRACK_OVCS_IDS];
+static int track_ovcs_id_overlay_nr[MAX_TRACK_OVCS_IDS];
+static int track_ovcs_id_cnt;
+
+static void of_unittest_track_overlay(int ovcs_id, int overlay_nr)
+{
+	if (WARN_ON(track_ovcs_id_cnt >= MAX_TRACK_OVCS_IDS))
+		return;
+
+	track_ovcs_id[track_ovcs_id_cnt] = ovcs_id;
+	track_ovcs_id_overlay_nr[track_ovcs_id_cnt] = overlay_nr;
+	track_ovcs_id_cnt++;
+}
+
+static void of_unittest_untrack_overlay(int ovcs_id)
+{
+	if (WARN_ON(track_ovcs_id_cnt < 1))
+		return;
+
+	track_ovcs_id_cnt--;
+
+	/* If out of synch then test is broken.  Do not try to recover. */
+	WARN_ON(track_ovcs_id[track_ovcs_id_cnt] != ovcs_id);
+}
+
+static void of_unittest_remove_tracked_overlays(void)
+{
+	int ret, ovcs_id, overlay_nr, save_ovcs_id;
+	const char *overlay_name;
+
+	while (track_ovcs_id_cnt > 0) {
+
+		ovcs_id = track_ovcs_id[track_ovcs_id_cnt - 1];
+		overlay_nr = track_ovcs_id_overlay_nr[track_ovcs_id_cnt - 1];
+		save_ovcs_id = ovcs_id;
+		ret = of_overlay_remove(&ovcs_id);
+		if (ret == -ENODEV) {
+			overlay_name = overlay_name_from_nr(overlay_nr);
+			pr_warn("%s: of_overlay_remove() for overlay \"%s\" failed, ret = %d\n",
+				__func__, overlay_name, ret);
+		}
+		of_unittest_untrack_overlay(save_ovcs_id);
+	}
+
+}
+
+static int __init of_unittest_apply_overlay(int overlay_nr, int *ovcs_id)
+{
+	/*
+	 * The overlay will be tracked, thus it will be removed
+	 * by of_unittest_remove_tracked_overlays().
+	 */
+
+	const char *overlay_name;
+
+	overlay_name = overlay_name_from_nr(overlay_nr);
+
+	if (!overlay_data_apply(overlay_name, ovcs_id)) {
+		unittest(0, "could not apply overlay \"%s\"\n", overlay_name);
+		return -EFAULT;
+	}
+	of_unittest_track_overlay(*ovcs_id, overlay_nr);
+
+	return 0;
+}
+
+static int __init __of_unittest_apply_overlay_check(int overlay_nr,
+		int unittest_nr, int before, int after,
+		enum overlay_type ovtype)
+{
+	int ret, ovcs_id;
+
+	/* unittest device must be in before state */
+	if (of_unittest_device_exists(unittest_nr, ovtype) != before) {
+		unittest(0, "%s with device @\"%s\" %s\n",
+				overlay_name_from_nr(overlay_nr),
+				unittest_path(unittest_nr, ovtype),
+				!before ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	/* apply the overlay */
+	ovcs_id = 0;
+	ret = of_unittest_apply_overlay(overlay_nr, &ovcs_id);
+	if (ret != 0) {
+		/* of_unittest_apply_overlay already called unittest() */
+		return ret;
+	}
+
+	/* unittest device must be in after state */
+	if (of_unittest_device_exists(unittest_nr, ovtype) != after) {
+		unittest(0, "%s with device @\"%s\" %s\n",
+				overlay_name_from_nr(overlay_nr),
+				unittest_path(unittest_nr, ovtype),
+				!after ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	return ovcs_id;
+}
+
+/* apply an overlay while checking before and after states */
+static int __init of_unittest_apply_overlay_check(int overlay_nr,
+		int unittest_nr, int before, int after,
+		enum overlay_type ovtype)
+{
+	int ovcs_id = __of_unittest_apply_overlay_check(overlay_nr,
+				unittest_nr, before, after, ovtype);
+	if (ovcs_id < 0)
+		return ovcs_id;
+
+	return 0;
+}
+
+/* apply an overlay and then revert it while checking before, after states */
+static int __init of_unittest_apply_revert_overlay_check(int overlay_nr,
+		int unittest_nr, int before, int after,
+		enum overlay_type ovtype)
+{
+	int ret, ovcs_id, save_ovcs_id;
+
+	ovcs_id = __of_unittest_apply_overlay_check(overlay_nr, unittest_nr,
+						    before, after, ovtype);
+	if (ovcs_id < 0)
+		return ovcs_id;
+
+	/* remove the overlay */
+	save_ovcs_id = ovcs_id;
+	ret = of_overlay_remove(&ovcs_id);
+	if (ret != 0) {
+		unittest(0, "%s failed to be destroyed @\"%s\"\n",
+				overlay_name_from_nr(overlay_nr),
+				unittest_path(unittest_nr, ovtype));
+		return ret;
+	}
+	of_unittest_untrack_overlay(save_ovcs_id);
+
+	/* unittest device must be again in before state */
+	if (of_unittest_device_exists(unittest_nr, ovtype) != before) {
+		unittest(0, "%s with device @\"%s\" %s\n",
+				overlay_name_from_nr(overlay_nr),
+				unittest_path(unittest_nr, ovtype),
+				!before ? "enabled" : "disabled");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* test activation of device */
+static void __init of_unittest_overlay_0(void)
+{
+	int ret;
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest0/status");
+
+	/* device should enable */
+	ret = of_unittest_apply_overlay_check(0, 0, 0, 1, PDEV_OVERLAY);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest0/status");
+
+	if (ret)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 0);
+}
+
+/* test deactivation of device */
+static void __init of_unittest_overlay_1(void)
+{
+	int ret;
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest1/status");
+
+	/* device should disable */
+	ret = of_unittest_apply_overlay_check(1, 1, 1, 0, PDEV_OVERLAY);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest1/status");
+
+	if (ret)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 1);
+
+}
+
+/* test activation of device */
+static void __init of_unittest_overlay_2(void)
+{
+	int ret;
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest2/status");
+
+	/* device should enable */
+	ret = of_unittest_apply_overlay_check(2, 2, 0, 1, PDEV_OVERLAY);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest2/status");
+
+	if (ret)
+		return;
+	unittest(1, "overlay test %d passed\n", 2);
+}
+
+/* test deactivation of device */
+static void __init of_unittest_overlay_3(void)
+{
+	int ret;
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest3/status");
+
+	/* device should disable */
+	ret = of_unittest_apply_overlay_check(3, 3, 1, 0, PDEV_OVERLAY);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest3/status");
+
+	if (ret)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 3);
+}
+
+/* test activation of a full device node */
+static void __init of_unittest_overlay_4(void)
+{
+	/* device should disable */
+	if (of_unittest_apply_overlay_check(4, 4, 0, 1, PDEV_OVERLAY))
+		return;
+
+	unittest(1, "overlay test %d passed\n", 4);
+}
+
+/* test overlay apply/revert sequence */
+static void __init of_unittest_overlay_5(void)
+{
+	int ret;
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest5/status");
+
+	/* device should disable */
+	ret = of_unittest_apply_revert_overlay_check(5, 5, 0, 1, PDEV_OVERLAY);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest5/status");
+
+	if (ret)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 5);
+}
+
+/* test overlay application in sequence */
+static void __init of_unittest_overlay_6(void)
+{
+	int i, save_ovcs_id[2], ovcs_id;
+	int overlay_nr = 6, unittest_nr = 6;
+	int before = 0, after = 1;
+	const char *overlay_name;
+
+	int ret;
+
+	/* unittest device must be in before state */
+	for (i = 0; i < 2; i++) {
+		if (of_unittest_device_exists(unittest_nr + i, PDEV_OVERLAY)
+				!= before) {
+			unittest(0, "%s with device @\"%s\" %s\n",
+					overlay_name_from_nr(overlay_nr + i),
+					unittest_path(unittest_nr + i,
+						PDEV_OVERLAY),
+					!before ? "enabled" : "disabled");
+			return;
+		}
+	}
+
+	/* apply the overlays */
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest6/status");
+
+	overlay_name = overlay_name_from_nr(overlay_nr + 0);
+
+	ret = overlay_data_apply(overlay_name, &ovcs_id);
+
+	if (!ret) {
+		unittest(0, "could not apply overlay \"%s\"\n", overlay_name);
+			return;
+	}
+	save_ovcs_id[0] = ovcs_id;
+	of_unittest_track_overlay(ovcs_id, overlay_nr + 0);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest6/status");
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest7/status");
+
+	overlay_name = overlay_name_from_nr(overlay_nr + 1);
+
+	ret = overlay_data_apply(overlay_name, &ovcs_id);
+
+	if (!ret) {
+		unittest(0, "could not apply overlay \"%s\"\n", overlay_name);
+			return;
+	}
+	save_ovcs_id[1] = ovcs_id;
+	of_unittest_track_overlay(ovcs_id, overlay_nr + 1);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest7/status");
+
+
+	for (i = 0; i < 2; i++) {
+		/* unittest device must be in after state */
+		if (of_unittest_device_exists(unittest_nr + i, PDEV_OVERLAY)
+				!= after) {
+			unittest(0, "overlay @\"%s\" failed @\"%s\" %s\n",
+					overlay_name_from_nr(overlay_nr + i),
+					unittest_path(unittest_nr + i,
+						PDEV_OVERLAY),
+					!after ? "enabled" : "disabled");
+			return;
+		}
+	}
+
+	for (i = 1; i >= 0; i--) {
+		ovcs_id = save_ovcs_id[i];
+		if (of_overlay_remove(&ovcs_id)) {
+			unittest(0, "%s failed destroy @\"%s\"\n",
+					overlay_name_from_nr(overlay_nr + i),
+					unittest_path(unittest_nr + i,
+						PDEV_OVERLAY));
+			return;
+		}
+		of_unittest_untrack_overlay(save_ovcs_id[i]);
+	}
+
+	for (i = 0; i < 2; i++) {
+		/* unittest device must be again in before state */
+		if (of_unittest_device_exists(unittest_nr + i, PDEV_OVERLAY)
+				!= before) {
+			unittest(0, "%s with device @\"%s\" %s\n",
+					overlay_name_from_nr(overlay_nr + i),
+					unittest_path(unittest_nr + i,
+						PDEV_OVERLAY),
+					!before ? "enabled" : "disabled");
+			return;
+		}
+	}
+
+	unittest(1, "overlay test %d passed\n", 6);
+
+}
+
+/* test overlay application in sequence */
+static void __init of_unittest_overlay_8(void)
+{
+	int i, save_ovcs_id[2], ovcs_id;
+	int overlay_nr = 8, unittest_nr = 8;
+	const char *overlay_name;
+	int ret;
+
+	/* we don't care about device state in this test */
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest8/status");
+
+	overlay_name = overlay_name_from_nr(overlay_nr + 0);
+
+	ret = overlay_data_apply(overlay_name, &ovcs_id);
+	if (!ret)
+		unittest(0, "could not apply overlay \"%s\"\n", overlay_name);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest8/status");
+
+	if (!ret)
+		return;
+
+	save_ovcs_id[0] = ovcs_id;
+	of_unittest_track_overlay(ovcs_id, overlay_nr + 0);
+
+	overlay_name = overlay_name_from_nr(overlay_nr + 1);
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest8/property-foo");
+
+	/* apply the overlays */
+	ret = overlay_data_apply(overlay_name, &ovcs_id);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/test-unittest8/property-foo");
+
+	if (!ret) {
+		unittest(0, "could not apply overlay \"%s\"\n", overlay_name);
+		return;
+	}
+
+	save_ovcs_id[1] = ovcs_id;
+	of_unittest_track_overlay(ovcs_id, overlay_nr + 1);
+
+	/* now try to remove first overlay (it should fail) */
+	ovcs_id = save_ovcs_id[0];
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: node_overlaps_later_cs: #6 overlaps with #7 @/testcase-data/overlay-node/test-bus/test-unittest8");
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: overlay #6 is not topmost");
+
+	ret = of_overlay_remove(&ovcs_id);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: overlay #6 is not topmost");
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: node_overlaps_later_cs: #6 overlaps with #7 @/testcase-data/overlay-node/test-bus/test-unittest8");
+
+	if (!ret) {
+		/*
+		 * Should never get here.  If we do, expect a lot of
+		 * subsequent tracking and overlay removal related errors.
+		 */
+		unittest(0, "%s was destroyed @\"%s\"\n",
+				overlay_name_from_nr(overlay_nr + 0),
+				unittest_path(unittest_nr,
+					PDEV_OVERLAY));
+		return;
+	}
+
+	/* removing them in order should work */
+	for (i = 1; i >= 0; i--) {
+		ovcs_id = save_ovcs_id[i];
+		if (of_overlay_remove(&ovcs_id)) {
+			unittest(0, "%s not destroyed @\"%s\"\n",
+					overlay_name_from_nr(overlay_nr + i),
+					unittest_path(unittest_nr,
+						PDEV_OVERLAY));
+			return;
+		}
+		of_unittest_untrack_overlay(save_ovcs_id[i]);
+	}
+
+	unittest(1, "overlay test %d passed\n", 8);
+}
+
+/* test insertion of a bus with parent devices */
+static void __init of_unittest_overlay_10(void)
+{
+	int ret;
+	char *child_path;
+
+	/* device should disable */
+	ret = of_unittest_apply_overlay_check(10, 10, 0, 1, PDEV_OVERLAY);
+
+	if (unittest(ret == 0,
+			"overlay test %d failed; overlay application\n", 10))
+		return;
+
+	child_path = kasprintf(GFP_KERNEL, "%s/test-unittest101",
+			unittest_path(10, PDEV_OVERLAY));
+	if (unittest(child_path, "overlay test %d failed; kasprintf\n", 10))
+		return;
+
+	ret = of_path_device_type_exists(child_path, PDEV_OVERLAY);
+	kfree(child_path);
+
+	unittest(ret, "overlay test %d failed; no child device\n", 10);
+}
+
+/* test insertion of a bus with parent devices (and revert) */
+static void __init of_unittest_overlay_11(void)
+{
+	int ret;
+
+	/* device should disable */
+	ret = of_unittest_apply_revert_overlay_check(11, 11, 0, 1,
+			PDEV_OVERLAY);
+
+	unittest(ret == 0, "overlay test %d failed; overlay apply\n", 11);
+}
+
+#if IS_BUILTIN(CONFIG_I2C) && IS_ENABLED(CONFIG_OF_OVERLAY)
+
+struct unittest_i2c_bus_data {
+	struct platform_device	*pdev;
+	struct i2c_adapter	adap;
+};
+
+static int unittest_i2c_master_xfer(struct i2c_adapter *adap,
+		struct i2c_msg *msgs, int num)
+{
+	struct unittest_i2c_bus_data *std = i2c_get_adapdata(adap);
+
+	(void)std;
+
+	return num;
+}
+
+static u32 unittest_i2c_functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm unittest_i2c_algo = {
+	.master_xfer	= unittest_i2c_master_xfer,
+	.functionality	= unittest_i2c_functionality,
+};
+
+static int unittest_i2c_bus_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct unittest_i2c_bus_data *std;
+	struct i2c_adapter *adap;
+	int ret;
+
+	if (np == NULL) {
+		dev_err(dev, "No OF data for device\n");
+		return -EINVAL;
+
+	}
+
+	dev_dbg(dev, "%s for node @%pOF\n", __func__, np);
+
+	std = devm_kzalloc(dev, sizeof(*std), GFP_KERNEL);
+	if (!std)
+		return -ENOMEM;
+
+	/* link them together */
+	std->pdev = pdev;
+	platform_set_drvdata(pdev, std);
+
+	adap = &std->adap;
+	i2c_set_adapdata(adap, std);
+	adap->nr = -1;
+	strscpy(adap->name, pdev->name, sizeof(adap->name));
+	adap->class = I2C_CLASS_DEPRECATED;
+	adap->algo = &unittest_i2c_algo;
+	adap->dev.parent = dev;
+	adap->dev.of_node = dev->of_node;
+	adap->timeout = 5 * HZ;
+	adap->retries = 3;
+
+	ret = i2c_add_numbered_adapter(adap);
+	if (ret != 0) {
+		dev_err(dev, "Failed to add I2C adapter\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static void unittest_i2c_bus_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct unittest_i2c_bus_data *std = platform_get_drvdata(pdev);
+
+	dev_dbg(dev, "%s for node @%pOF\n", __func__, np);
+	i2c_del_adapter(&std->adap);
+}
+
+static const struct of_device_id unittest_i2c_bus_match[] = {
+	{ .compatible = "unittest-i2c-bus", },
+	{},
+};
+
+static struct platform_driver unittest_i2c_bus_driver = {
+	.probe			= unittest_i2c_bus_probe,
+	.remove_new		= unittest_i2c_bus_remove,
+	.driver = {
+		.name		= "unittest-i2c-bus",
+		.of_match_table	= unittest_i2c_bus_match,
+	},
+};
+
+static int unittest_i2c_dev_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct device_node *np = client->dev.of_node;
+
+	if (!np) {
+		dev_err(dev, "No OF node\n");
+		return -EINVAL;
+	}
+
+	dev_dbg(dev, "%s for node @%pOF\n", __func__, np);
+
+	return 0;
+};
+
+static void unittest_i2c_dev_remove(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct device_node *np = client->dev.of_node;
+
+	dev_dbg(dev, "%s for node @%pOF\n", __func__, np);
+}
+
+static const struct i2c_device_id unittest_i2c_dev_id[] = {
+	{ .name = "unittest-i2c-dev" },
+	{ }
+};
+
+static struct i2c_driver unittest_i2c_dev_driver = {
+	.driver = {
+		.name = "unittest-i2c-dev",
+	},
+	.probe = unittest_i2c_dev_probe,
+	.remove = unittest_i2c_dev_remove,
+	.id_table = unittest_i2c_dev_id,
+};
+
+#if IS_BUILTIN(CONFIG_I2C_MUX)
+
+static int unittest_i2c_mux_select_chan(struct i2c_mux_core *muxc, u32 chan)
+{
+	return 0;
+}
+
+static int unittest_i2c_mux_probe(struct i2c_client *client)
+{
+	int i, nchans;
+	struct device *dev = &client->dev;
+	struct i2c_adapter *adap = client->adapter;
+	struct device_node *np = client->dev.of_node, *child;
+	struct i2c_mux_core *muxc;
+	u32 reg, max_reg;
+
+	dev_dbg(dev, "%s for node @%pOF\n", __func__, np);
+
+	if (!np) {
+		dev_err(dev, "No OF node\n");
+		return -EINVAL;
+	}
+
+	max_reg = (u32)-1;
+	for_each_child_of_node(np, child) {
+		if (of_property_read_u32(child, "reg", &reg))
+			continue;
+		if (max_reg == (u32)-1 || reg > max_reg)
+			max_reg = reg;
+	}
+	nchans = max_reg == (u32)-1 ? 0 : max_reg + 1;
+	if (nchans == 0) {
+		dev_err(dev, "No channels\n");
+		return -EINVAL;
+	}
+
+	muxc = i2c_mux_alloc(adap, dev, nchans, 0, 0,
+			     unittest_i2c_mux_select_chan, NULL);
+	if (!muxc)
+		return -ENOMEM;
+	for (i = 0; i < nchans; i++) {
+		if (i2c_mux_add_adapter(muxc, 0, i, 0)) {
+			dev_err(dev, "Failed to register mux #%d\n", i);
+			i2c_mux_del_adapters(muxc);
+			return -ENODEV;
+		}
+	}
+
+	i2c_set_clientdata(client, muxc);
+
+	return 0;
+};
+
+static void unittest_i2c_mux_remove(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct device_node *np = client->dev.of_node;
+	struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+
+	dev_dbg(dev, "%s for node @%pOF\n", __func__, np);
+	i2c_mux_del_adapters(muxc);
+}
+
+static const struct i2c_device_id unittest_i2c_mux_id[] = {
+	{ .name = "unittest-i2c-mux" },
+	{ }
+};
+
+static struct i2c_driver unittest_i2c_mux_driver = {
+	.driver = {
+		.name = "unittest-i2c-mux",
+	},
+	.probe = unittest_i2c_mux_probe,
+	.remove = unittest_i2c_mux_remove,
+	.id_table = unittest_i2c_mux_id,
+};
+
+#endif
+
+static int of_unittest_overlay_i2c_init(void)
+{
+	int ret;
+
+	ret = i2c_add_driver(&unittest_i2c_dev_driver);
+	if (unittest(ret == 0,
+			"could not register unittest i2c device driver\n"))
+		return ret;
+
+	ret = platform_driver_register(&unittest_i2c_bus_driver);
+
+	if (unittest(ret == 0,
+			"could not register unittest i2c bus driver\n"))
+		return ret;
+
+#if IS_BUILTIN(CONFIG_I2C_MUX)
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "i2c i2c-1: Added multiplexed i2c bus 2");
+
+	ret = i2c_add_driver(&unittest_i2c_mux_driver);
+
+	EXPECT_END(KERN_INFO,
+		   "i2c i2c-1: Added multiplexed i2c bus 2");
+
+	if (unittest(ret == 0,
+			"could not register unittest i2c mux driver\n"))
+		return ret;
+#endif
+
+	return 0;
+}
+
+static void of_unittest_overlay_i2c_cleanup(void)
+{
+#if IS_BUILTIN(CONFIG_I2C_MUX)
+	i2c_del_driver(&unittest_i2c_mux_driver);
+#endif
+	platform_driver_unregister(&unittest_i2c_bus_driver);
+	i2c_del_driver(&unittest_i2c_dev_driver);
+}
+
+static void __init of_unittest_overlay_i2c_12(void)
+{
+	int ret;
+
+	/* device should enable */
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/i2c-test-bus/test-unittest12/status");
+
+	ret = of_unittest_apply_overlay_check(12, 12, 0, 1, I2C_OVERLAY);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/i2c-test-bus/test-unittest12/status");
+
+	if (ret)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 12);
+}
+
+/* test deactivation of device */
+static void __init of_unittest_overlay_i2c_13(void)
+{
+	int ret;
+
+	EXPECT_BEGIN(KERN_INFO,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/i2c-test-bus/test-unittest13/status");
+
+	/* device should disable */
+	ret = of_unittest_apply_overlay_check(13, 13, 1, 0, I2C_OVERLAY);
+
+	EXPECT_END(KERN_INFO,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data/overlay-node/test-bus/i2c-test-bus/test-unittest13/status");
+
+	if (ret)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 13);
+}
+
+/* just check for i2c mux existence */
+static void of_unittest_overlay_i2c_14(void)
+{
+}
+
+static void __init of_unittest_overlay_i2c_15(void)
+{
+	int ret;
+
+	/* device should enable */
+	EXPECT_BEGIN(KERN_INFO,
+		     "i2c i2c-1: Added multiplexed i2c bus 3");
+
+	ret = of_unittest_apply_overlay_check(15, 15, 0, 1, I2C_OVERLAY);
+
+	EXPECT_END(KERN_INFO,
+		   "i2c i2c-1: Added multiplexed i2c bus 3");
+
+	if (ret)
+		return;
+
+	unittest(1, "overlay test %d passed\n", 15);
+}
+
+#else
+
+static inline void of_unittest_overlay_i2c_14(void) { }
+static inline void of_unittest_overlay_i2c_15(void) { }
+
+#endif
+
+static int of_notify(struct notifier_block *nb, unsigned long action,
+		     void *arg)
+{
+	struct of_overlay_notify_data *nd = arg;
+	struct device_node *found;
+	int ret;
+
+	/*
+	 * For overlay_16 .. overlay_19, check that returning an error
+	 * works for each of the actions by setting an arbitrary return
+	 * error number that matches the test number.  e.g. for unittest16,
+	 * ret = -EBUSY which is -16.
+	 *
+	 * OVERLAY_INFO() for the overlays is declared to expect the same
+	 * error number, so overlay_data_apply() will return no error.
+	 *
+	 * overlay_20 will return NOTIFY_DONE
+	 */
+
+	ret = 0;
+	of_node_get(nd->overlay);
+
+	switch (action) {
+
+	case OF_OVERLAY_PRE_APPLY:
+		found = of_find_node_by_name(nd->overlay, "test-unittest16");
+		if (found) {
+			of_node_put(found);
+			ret = -EBUSY;
+		}
+		break;
+
+	case OF_OVERLAY_POST_APPLY:
+		found = of_find_node_by_name(nd->overlay, "test-unittest17");
+		if (found) {
+			of_node_put(found);
+			ret = -EEXIST;
+		}
+		break;
+
+	case OF_OVERLAY_PRE_REMOVE:
+		found = of_find_node_by_name(nd->overlay, "test-unittest18");
+		if (found) {
+			of_node_put(found);
+			ret = -EXDEV;
+		}
+		break;
+
+	case OF_OVERLAY_POST_REMOVE:
+		found = of_find_node_by_name(nd->overlay, "test-unittest19");
+		if (found) {
+			of_node_put(found);
+			ret = -ENODEV;
+		}
+		break;
+
+	default:			/* should not happen */
+		of_node_put(nd->overlay);
+		ret = -EINVAL;
+		break;
+	}
+
+	if (ret)
+		return notifier_from_errno(ret);
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block of_nb = {
+	.notifier_call = of_notify,
+};
+
+static void __init of_unittest_overlay_notify(void)
+{
+	int ovcs_id;
+	int ret;
+
+	ret = of_overlay_notifier_register(&of_nb);
+	unittest(!ret,
+		 "of_overlay_notifier_register() failed, ret = %d\n", ret);
+	if (ret)
+		return;
+
+	/*
+	 * The overlays are applied by overlay_data_apply()
+	 * instead of of_unittest_apply_overlay() so that they
+	 * will not be tracked.  Thus they will not be removed
+	 * by of_unittest_remove_tracked_overlays().
+	 *
+	 * Applying overlays 16 - 19 will each trigger an error for a
+	 * different action in of_notify().
+	 *
+	 * Applying overlay 20 will not trigger any error in of_notify().
+	 */
+
+	/* ---  overlay 16  --- */
+
+	EXPECT_BEGIN(KERN_INFO, "OF: overlay: overlay changeset pre-apply notifier error -16, target: /testcase-data/overlay-node/test-bus");
+
+	unittest(overlay_data_apply("overlay_16", &ovcs_id),
+		 "test OF_OVERLAY_PRE_APPLY notify injected error\n");
+
+	EXPECT_END(KERN_INFO, "OF: overlay: overlay changeset pre-apply notifier error -16, target: /testcase-data/overlay-node/test-bus");
+
+	unittest(ovcs_id, "ovcs_id not created for overlay_16\n");
+
+	/* ---  overlay 17  --- */
+
+	EXPECT_BEGIN(KERN_INFO, "OF: overlay: overlay changeset post-apply notifier error -17, target: /testcase-data/overlay-node/test-bus");
+
+	unittest(overlay_data_apply("overlay_17", &ovcs_id),
+		 "test OF_OVERLAY_POST_APPLY notify injected error\n");
+
+	EXPECT_END(KERN_INFO, "OF: overlay: overlay changeset post-apply notifier error -17, target: /testcase-data/overlay-node/test-bus");
+
+	unittest(ovcs_id, "ovcs_id not created for overlay_17\n");
+
+	/* ---  overlay 18  --- */
+
+	unittest(overlay_data_apply("overlay_18", &ovcs_id),
+		 "OF_OVERLAY_PRE_REMOVE notify injected error\n");
+
+	unittest(ovcs_id, "ovcs_id not created for overlay_18\n");
+
+	if (ovcs_id) {
+		EXPECT_BEGIN(KERN_INFO, "OF: overlay: overlay changeset pre-remove notifier error -18, target: /testcase-data/overlay-node/test-bus");
+
+		ret = of_overlay_remove(&ovcs_id);
+		EXPECT_END(KERN_INFO, "OF: overlay: overlay changeset pre-remove notifier error -18, target: /testcase-data/overlay-node/test-bus");
+		if (ret == -EXDEV) {
+			/*
+			 * change set ovcs_id should still exist
+			 */
+			unittest(1, "overlay_18 of_overlay_remove() injected error for OF_OVERLAY_PRE_REMOVE\n");
+		} else {
+			unittest(0, "overlay_18 of_overlay_remove() injected error for OF_OVERLAY_PRE_REMOVE not returned\n");
+		}
+	} else {
+		unittest(1, "ovcs_id not created for overlay_18\n");
+	}
+
+	unittest(ovcs_id, "ovcs_id removed for overlay_18\n");
+
+	/* ---  overlay 19  --- */
+
+	unittest(overlay_data_apply("overlay_19", &ovcs_id),
+		 "OF_OVERLAY_POST_REMOVE notify injected error\n");
+
+	unittest(ovcs_id, "ovcs_id not created for overlay_19\n");
+
+	if (ovcs_id) {
+		EXPECT_BEGIN(KERN_INFO, "OF: overlay: overlay changeset post-remove notifier error -19, target: /testcase-data/overlay-node/test-bus");
+		ret = of_overlay_remove(&ovcs_id);
+		EXPECT_END(KERN_INFO, "OF: overlay: overlay changeset post-remove notifier error -19, target: /testcase-data/overlay-node/test-bus");
+		if (ret == -ENODEV)
+			unittest(1, "overlay_19 of_overlay_remove() injected error for OF_OVERLAY_POST_REMOVE\n");
+		else
+			unittest(0, "overlay_19 of_overlay_remove() injected error for OF_OVERLAY_POST_REMOVE not returned\n");
+	} else {
+		unittest(1, "ovcs_id removed for overlay_19\n");
+	}
+
+	unittest(!ovcs_id, "changeset ovcs_id = %d not removed for overlay_19\n",
+		 ovcs_id);
+
+	/* ---  overlay 20  --- */
+
+	unittest(overlay_data_apply("overlay_20", &ovcs_id),
+		 "overlay notify no injected error\n");
+
+	if (ovcs_id) {
+		ret = of_overlay_remove(&ovcs_id);
+		if (ret)
+			unittest(1, "overlay_20 failed to be destroyed, ret = %d\n",
+				 ret);
+	} else {
+		unittest(1, "ovcs_id not created for overlay_20\n");
+	}
+
+	unittest(!of_overlay_notifier_unregister(&of_nb),
+		 "of_overlay_notifier_unregister() failed, ret = %d\n", ret);
+}
+
+static void __init of_unittest_overlay(void)
+{
+	struct device_node *bus_np = NULL;
+	unsigned int i;
+
+	if (platform_driver_register(&unittest_driver)) {
+		unittest(0, "could not register unittest driver\n");
+		goto out;
+	}
+
+	bus_np = of_find_node_by_path(bus_path);
+	if (bus_np == NULL) {
+		unittest(0, "could not find bus_path \"%s\"\n", bus_path);
+		goto out;
+	}
+
+	if (of_platform_default_populate(bus_np, NULL, NULL)) {
+		unittest(0, "could not populate bus @ \"%s\"\n", bus_path);
+		goto out;
+	}
+
+	if (!of_unittest_device_exists(100, PDEV_OVERLAY)) {
+		unittest(0, "could not find unittest0 @ \"%s\"\n",
+				unittest_path(100, PDEV_OVERLAY));
+		goto out;
+	}
+
+	if (of_unittest_device_exists(101, PDEV_OVERLAY)) {
+		unittest(0, "unittest1 @ \"%s\" should not exist\n",
+				unittest_path(101, PDEV_OVERLAY));
+		goto out;
+	}
+
+	unittest(1, "basic infrastructure of overlays passed");
+
+	/* tests in sequence */
+	of_unittest_overlay_0();
+	of_unittest_overlay_1();
+	of_unittest_overlay_2();
+	of_unittest_overlay_3();
+	of_unittest_overlay_4();
+	for (i = 0; i < 3; i++)
+		of_unittest_overlay_5();
+	of_unittest_overlay_6();
+	of_unittest_overlay_8();
+
+	of_unittest_overlay_10();
+	of_unittest_overlay_11();
+
+#if IS_BUILTIN(CONFIG_I2C)
+	if (unittest(of_unittest_overlay_i2c_init() == 0, "i2c init failed\n"))
+		goto out;
+
+	of_unittest_overlay_i2c_12();
+	of_unittest_overlay_i2c_13();
+	of_unittest_overlay_i2c_14();
+	of_unittest_overlay_i2c_15();
+
+	of_unittest_overlay_i2c_cleanup();
+#endif
+
+	of_unittest_overlay_gpio();
+
+	of_unittest_remove_tracked_overlays();
+
+	of_unittest_overlay_notify();
+
+out:
+	of_node_put(bus_np);
+}
+
+#else
+static inline void __init of_unittest_overlay(void) { }
+#endif
+
+static void __init of_unittest_lifecycle(void)
+{
+#ifdef CONFIG_OF_DYNAMIC
+	unsigned int refcount;
+	int found_refcount_one = 0;
+	int put_count = 0;
+	struct device_node *np;
+	struct device_node *prev_sibling, *next_sibling;
+	const char *refcount_path = "/testcase-data/refcount-node";
+	const char *refcount_parent_path = "/testcase-data";
+
+	/*
+	 * Node lifecycle tests, non-dynamic node:
+	 *
+	 * - Decrementing refcount to zero via of_node_put() should cause the
+	 *   attempt to free the node memory by of_node_release() to fail
+	 *   because the node is not a dynamic node.
+	 *
+	 * - Decrementing refcount past zero should result in additional
+	 *   errors reported.
+	 */
+
+	np = of_find_node_by_path(refcount_path);
+	unittest(np, "find refcount_path \"%s\"\n", refcount_path);
+	if (np == NULL)
+		goto out_skip_tests;
+
+	while (!found_refcount_one) {
+
+		if (put_count++ > 10) {
+			unittest(0, "guardrail to avoid infinite loop\n");
+			goto out_skip_tests;
+		}
+
+		refcount = kref_read(&np->kobj.kref);
+		if (refcount == 1)
+			found_refcount_one = 1;
+		else
+			of_node_put(np);
+	}
+
+	EXPECT_BEGIN(KERN_INFO, "OF: ERROR: of_node_release() detected bad of_node_put() on /testcase-data/refcount-node");
+
+	/*
+	 * refcount is now one, decrementing to zero will result in a call to
+	 * of_node_release() to free the node's memory, which should result
+	 * in an error
+	 */
+	unittest(1, "/testcase-data/refcount-node is one");
+	of_node_put(np);
+
+	EXPECT_END(KERN_INFO, "OF: ERROR: of_node_release() detected bad of_node_put() on /testcase-data/refcount-node");
+
+
+	/*
+	 * expect stack trace for subsequent of_node_put():
+	 *   __refcount_sub_and_test() calls:
+	 *   refcount_warn_saturate(r, REFCOUNT_SUB_UAF)
+	 *
+	 * Not capturing entire WARN_ONCE() trace with EXPECT_*(), just
+	 * the first three lines, and the last line.
+	 */
+	EXPECT_BEGIN(KERN_INFO, "------------[ cut here ]------------");
+	EXPECT_BEGIN(KERN_INFO, "WARNING: <<all>>");
+	EXPECT_BEGIN(KERN_INFO, "refcount_t: underflow; use-after-free.");
+	EXPECT_BEGIN(KERN_INFO, "---[ end trace <<int>> ]---");
+
+	/* refcount is now zero, this should fail */
+	unittest(1, "/testcase-data/refcount-node is zero");
+	of_node_put(np);
+
+	EXPECT_END(KERN_INFO, "---[ end trace <<int>> ]---");
+	EXPECT_END(KERN_INFO, "refcount_t: underflow; use-after-free.");
+	EXPECT_END(KERN_INFO, "WARNING: <<all>>");
+	EXPECT_END(KERN_INFO, "------------[ cut here ]------------");
+
+	/*
+	 * Q. do we expect to get yet another warning?
+	 * A. no, the WARNING is from WARN_ONCE()
+	 */
+	EXPECT_NOT_BEGIN(KERN_INFO, "------------[ cut here ]------------");
+	EXPECT_NOT_BEGIN(KERN_INFO, "WARNING: <<all>>");
+	EXPECT_NOT_BEGIN(KERN_INFO, "refcount_t: underflow; use-after-free.");
+	EXPECT_NOT_BEGIN(KERN_INFO, "---[ end trace <<int>> ]---");
+
+	unittest(1, "/testcase-data/refcount-node is zero, second time");
+	of_node_put(np);
+
+	EXPECT_NOT_END(KERN_INFO, "---[ end trace <<int>> ]---");
+	EXPECT_NOT_END(KERN_INFO, "refcount_t: underflow; use-after-free.");
+	EXPECT_NOT_END(KERN_INFO, "WARNING: <<all>>");
+	EXPECT_NOT_END(KERN_INFO, "------------[ cut here ]------------");
+
+	/*
+	 * refcount of zero will trigger stack traces from any further
+	 * attempt to of_node_get() node "refcount-node". One example of
+	 * this is where of_unittest_check_node_linkage() will recursively
+	 * scan the tree, with 'for_each_child_of_node()' doing an
+	 * of_node_get() of the children of a node.
+	 *
+	 * Prevent the stack trace by removing node "refcount-node" from
+	 * its parent's child list.
+	 *
+	 * WARNING:  EVIL, EVIL, EVIL:
+	 *
+	 *   Directly manipulate the child list of node /testcase-data to
+	 *   remove child refcount-node.  This is ignoring all proper methods
+	 *   of removing a child and will leak a small amount of memory.
+	 */
+
+	np = of_find_node_by_path(refcount_parent_path);
+	unittest(np, "find refcount_parent_path \"%s\"\n", refcount_parent_path);
+	unittest(np, "ERROR: devicetree live tree left in a 'bad state' if test fail\n");
+	if (np == NULL)
+		return;
+
+	prev_sibling = np->child;
+	next_sibling = prev_sibling->sibling;
+	if (!strcmp(prev_sibling->full_name, "refcount-node")) {
+		np->child = next_sibling;
+		next_sibling = next_sibling->sibling;
+	}
+	while (next_sibling) {
+		if (!strcmp(next_sibling->full_name, "refcount-node"))
+			prev_sibling->sibling = next_sibling->sibling;
+		prev_sibling = next_sibling;
+		next_sibling = next_sibling->sibling;
+	}
+	of_node_put(np);
+
+	return;
+
+out_skip_tests:
+#endif
+	unittest(0, "One or more lifecycle tests skipped\n");
+}
+
+#ifdef CONFIG_OF_OVERLAY
+
+/*
+ * __dtbo_##overlay_name##_begin[] and __dtbo_##overlay_name##_end[] are
+ * created by cmd_dt_S_dtbo in scripts/Makefile.lib
+ */
+
+#define OVERLAY_INFO_EXTERN(overlay_name) \
+	extern uint8_t __dtbo_##overlay_name##_begin[]; \
+	extern uint8_t __dtbo_##overlay_name##_end[]
+
+#define OVERLAY_INFO(overlay_name, expected, expected_remove) \
+{	.dtbo_begin		= __dtbo_##overlay_name##_begin, \
+	.dtbo_end		= __dtbo_##overlay_name##_end, \
+	.expected_result	= expected, \
+	.expected_result_remove	= expected_remove, \
+	.name			= #overlay_name, \
+}
+
+struct overlay_info {
+	uint8_t		*dtbo_begin;
+	uint8_t		*dtbo_end;
+	int		expected_result;
+	int		expected_result_remove;	/* if apply failed */
+	int		ovcs_id;
+	char		*name;
+};
+
+OVERLAY_INFO_EXTERN(overlay_base);
+OVERLAY_INFO_EXTERN(overlay);
+OVERLAY_INFO_EXTERN(overlay_0);
+OVERLAY_INFO_EXTERN(overlay_1);
+OVERLAY_INFO_EXTERN(overlay_2);
+OVERLAY_INFO_EXTERN(overlay_3);
+OVERLAY_INFO_EXTERN(overlay_4);
+OVERLAY_INFO_EXTERN(overlay_5);
+OVERLAY_INFO_EXTERN(overlay_6);
+OVERLAY_INFO_EXTERN(overlay_7);
+OVERLAY_INFO_EXTERN(overlay_8);
+OVERLAY_INFO_EXTERN(overlay_9);
+OVERLAY_INFO_EXTERN(overlay_10);
+OVERLAY_INFO_EXTERN(overlay_11);
+OVERLAY_INFO_EXTERN(overlay_12);
+OVERLAY_INFO_EXTERN(overlay_13);
+OVERLAY_INFO_EXTERN(overlay_15);
+OVERLAY_INFO_EXTERN(overlay_16);
+OVERLAY_INFO_EXTERN(overlay_17);
+OVERLAY_INFO_EXTERN(overlay_18);
+OVERLAY_INFO_EXTERN(overlay_19);
+OVERLAY_INFO_EXTERN(overlay_20);
+OVERLAY_INFO_EXTERN(overlay_gpio_01);
+OVERLAY_INFO_EXTERN(overlay_gpio_02a);
+OVERLAY_INFO_EXTERN(overlay_gpio_02b);
+OVERLAY_INFO_EXTERN(overlay_gpio_03);
+OVERLAY_INFO_EXTERN(overlay_gpio_04a);
+OVERLAY_INFO_EXTERN(overlay_gpio_04b);
+OVERLAY_INFO_EXTERN(overlay_pci_node);
+OVERLAY_INFO_EXTERN(overlay_bad_add_dup_node);
+OVERLAY_INFO_EXTERN(overlay_bad_add_dup_prop);
+OVERLAY_INFO_EXTERN(overlay_bad_phandle);
+OVERLAY_INFO_EXTERN(overlay_bad_symbol);
+OVERLAY_INFO_EXTERN(overlay_bad_unresolved);
+
+/* entries found by name */
+static struct overlay_info overlays[] = {
+	OVERLAY_INFO(overlay_base, -9999, 0),
+	OVERLAY_INFO(overlay, 0, 0),
+	OVERLAY_INFO(overlay_0, 0, 0),
+	OVERLAY_INFO(overlay_1, 0, 0),
+	OVERLAY_INFO(overlay_2, 0, 0),
+	OVERLAY_INFO(overlay_3, 0, 0),
+	OVERLAY_INFO(overlay_4, 0, 0),
+	OVERLAY_INFO(overlay_5, 0, 0),
+	OVERLAY_INFO(overlay_6, 0, 0),
+	OVERLAY_INFO(overlay_7, 0, 0),
+	OVERLAY_INFO(overlay_8, 0, 0),
+	OVERLAY_INFO(overlay_9, 0, 0),
+	OVERLAY_INFO(overlay_10, 0, 0),
+	OVERLAY_INFO(overlay_11, 0, 0),
+	OVERLAY_INFO(overlay_12, 0, 0),
+	OVERLAY_INFO(overlay_13, 0, 0),
+	OVERLAY_INFO(overlay_15, 0, 0),
+	OVERLAY_INFO(overlay_16, -EBUSY, 0),
+	OVERLAY_INFO(overlay_17, -EEXIST, 0),
+	OVERLAY_INFO(overlay_18, 0, 0),
+	OVERLAY_INFO(overlay_19, 0, 0),
+	OVERLAY_INFO(overlay_20, 0, 0),
+	OVERLAY_INFO(overlay_gpio_01, 0, 0),
+	OVERLAY_INFO(overlay_gpio_02a, 0, 0),
+	OVERLAY_INFO(overlay_gpio_02b, 0, 0),
+	OVERLAY_INFO(overlay_gpio_03, 0, 0),
+	OVERLAY_INFO(overlay_gpio_04a, 0, 0),
+	OVERLAY_INFO(overlay_gpio_04b, 0, 0),
+	OVERLAY_INFO(overlay_pci_node, 0, 0),
+	OVERLAY_INFO(overlay_bad_add_dup_node, -EINVAL, -ENODEV),
+	OVERLAY_INFO(overlay_bad_add_dup_prop, -EINVAL, -ENODEV),
+	OVERLAY_INFO(overlay_bad_phandle, -EINVAL, 0),
+	OVERLAY_INFO(overlay_bad_symbol, -EINVAL, -ENODEV),
+	OVERLAY_INFO(overlay_bad_unresolved, -EINVAL, 0),
+	/* end marker */
+	{ }
+};
+
+static struct device_node *overlay_base_root;
+
+static void * __init dt_alloc_memory(u64 size, u64 align)
+{
+	void *ptr = memblock_alloc(size, align);
+
+	if (!ptr)
+		panic("%s: Failed to allocate %llu bytes align=0x%llx\n",
+		      __func__, size, align);
+
+	return ptr;
+}
+
+/*
+ * Create base device tree for the overlay unittest.
+ *
+ * This is called from very early boot code.
+ *
+ * Do as much as possible the same way as done in __unflatten_device_tree
+ * and other early boot steps for the normal FDT so that the overlay base
+ * unflattened tree will have the same characteristics as the real tree
+ * (such as having memory allocated by the early allocator).  The goal
+ * is to test "the real thing" as much as possible, and test "test setup
+ * code" as little as possible.
+ *
+ * Have to stop before resolving phandles, because that uses kmalloc.
+ */
+void __init unittest_unflatten_overlay_base(void)
+{
+	struct overlay_info *info;
+	u32 data_size;
+	void *new_fdt;
+	u32 size;
+	int found = 0;
+	const char *overlay_name = "overlay_base";
+
+	for (info = overlays; info && info->name; info++) {
+		if (!strcmp(overlay_name, info->name)) {
+			found = 1;
+			break;
+		}
+	}
+	if (!found) {
+		pr_err("no overlay data for %s\n", overlay_name);
+		return;
+	}
+
+	info = &overlays[0];
+
+	if (info->expected_result != -9999) {
+		pr_err("No dtb 'overlay_base' to attach\n");
+		return;
+	}
+
+	data_size = info->dtbo_end - info->dtbo_begin;
+	if (!data_size) {
+		pr_err("No dtb 'overlay_base' to attach\n");
+		return;
+	}
+
+	size = fdt_totalsize(info->dtbo_begin);
+	if (size != data_size) {
+		pr_err("dtb 'overlay_base' header totalsize != actual size");
+		return;
+	}
+
+	new_fdt = dt_alloc_memory(size, roundup_pow_of_two(FDT_V17_SIZE));
+	if (!new_fdt) {
+		pr_err("alloc for dtb 'overlay_base' failed");
+		return;
+	}
+
+	memcpy(new_fdt, info->dtbo_begin, size);
+
+	__unflatten_device_tree(new_fdt, NULL, &overlay_base_root,
+				dt_alloc_memory, true);
+}
+
+/*
+ * The purpose of of_unittest_overlay_data_add is to add an
+ * overlay in the normal fashion.  This is a test of the whole
+ * picture, instead of testing individual elements.
+ *
+ * A secondary purpose is to be able to verify that the contents of
+ * /proc/device-tree/ contains the updated structure and values from
+ * the overlay.  That must be verified separately in user space.
+ *
+ * Return 0 on unexpected error.
+ */
+static int __init overlay_data_apply(const char *overlay_name, int *ovcs_id)
+{
+	struct overlay_info *info;
+	int passed = 1;
+	int found = 0;
+	int ret, ret2;
+	u32 size;
+
+	for (info = overlays; info && info->name; info++) {
+		if (!strcmp(overlay_name, info->name)) {
+			found = 1;
+			break;
+		}
+	}
+	if (!found) {
+		pr_err("no overlay data for %s\n", overlay_name);
+		return 0;
+	}
+
+	size = info->dtbo_end - info->dtbo_begin;
+	if (!size)
+		pr_err("no overlay data for %s\n", overlay_name);
+
+	ret = of_overlay_fdt_apply(info->dtbo_begin, size, &info->ovcs_id,
+				   NULL);
+	if (ovcs_id)
+		*ovcs_id = info->ovcs_id;
+	if (ret < 0)
+		goto out;
+
+	pr_debug("%s applied\n", overlay_name);
+
+out:
+	if (ret != info->expected_result) {
+		pr_err("of_overlay_fdt_apply() expected %d, ret=%d, %s\n",
+		       info->expected_result, ret, overlay_name);
+		passed = 0;
+	}
+
+	if (ret < 0) {
+		/* changeset may be partially applied */
+		ret2 = of_overlay_remove(&info->ovcs_id);
+		if (ret2 != info->expected_result_remove) {
+			pr_err("of_overlay_remove() expected %d, ret=%d, %s\n",
+			       info->expected_result_remove, ret2,
+			       overlay_name);
+			passed = 0;
+		}
+	}
+
+	return passed;
+}
+
+/*
+ * The purpose of of_unittest_overlay_high_level is to add an overlay
+ * in the normal fashion.  This is a test of the whole picture,
+ * instead of individual elements.
+ *
+ * The first part of the function is _not_ normal overlay usage; it is
+ * finishing splicing the base overlay device tree into the live tree.
+ */
+static __init void of_unittest_overlay_high_level(void)
+{
+	struct device_node *last_sibling;
+	struct device_node *np;
+	struct device_node *of_symbols;
+	struct device_node *overlay_base_symbols;
+	struct device_node **pprev;
+	struct property *prop;
+	int ret;
+
+	if (!overlay_base_root) {
+		unittest(0, "overlay_base_root not initialized\n");
+		return;
+	}
+
+	/*
+	 * Could not fixup phandles in unittest_unflatten_overlay_base()
+	 * because kmalloc() was not yet available.
+	 */
+	of_overlay_mutex_lock();
+	of_resolve_phandles(overlay_base_root);
+	of_overlay_mutex_unlock();
+
+
+	/*
+	 * do not allow overlay_base to duplicate any node already in
+	 * tree, this greatly simplifies the code
+	 */
+
+	/*
+	 * remove overlay_base_root node "__local_fixups", after
+	 * being used by of_resolve_phandles()
+	 */
+	pprev = &overlay_base_root->child;
+	for (np = overlay_base_root->child; np; np = np->sibling) {
+		if (of_node_name_eq(np, "__local_fixups__")) {
+			*pprev = np->sibling;
+			break;
+		}
+		pprev = &np->sibling;
+	}
+
+	/* remove overlay_base_root node "__symbols__" if in live tree */
+	of_symbols = of_get_child_by_name(of_root, "__symbols__");
+	if (of_symbols) {
+		/* will have to graft properties from node into live tree */
+		pprev = &overlay_base_root->child;
+		for (np = overlay_base_root->child; np; np = np->sibling) {
+			if (of_node_name_eq(np, "__symbols__")) {
+				overlay_base_symbols = np;
+				*pprev = np->sibling;
+				break;
+			}
+			pprev = &np->sibling;
+		}
+	}
+
+	for_each_child_of_node(overlay_base_root, np) {
+		struct device_node *base_child;
+		for_each_child_of_node(of_root, base_child) {
+			if (!strcmp(np->full_name, base_child->full_name)) {
+				unittest(0, "illegal node name in overlay_base %pOFn",
+					 np);
+				of_node_put(np);
+				of_node_put(base_child);
+				return;
+			}
+		}
+	}
+
+	/*
+	 * overlay 'overlay_base' is not allowed to have root
+	 * properties, so only need to splice nodes into main device tree.
+	 *
+	 * root node of *overlay_base_root will not be freed, it is lost
+	 * memory.
+	 */
+
+	for (np = overlay_base_root->child; np; np = np->sibling)
+		np->parent = of_root;
+
+	mutex_lock(&of_mutex);
+
+	for (last_sibling = np = of_root->child; np; np = np->sibling)
+		last_sibling = np;
+
+	if (last_sibling)
+		last_sibling->sibling = overlay_base_root->child;
+	else
+		of_root->child = overlay_base_root->child;
+
+	for_each_of_allnodes_from(overlay_base_root, np)
+		__of_attach_node_sysfs(np);
+
+	if (of_symbols) {
+		struct property *new_prop;
+		for_each_property_of_node(overlay_base_symbols, prop) {
+
+			new_prop = __of_prop_dup(prop, GFP_KERNEL);
+			if (!new_prop) {
+				unittest(0, "__of_prop_dup() of '%s' from overlay_base node __symbols__",
+					 prop->name);
+				goto err_unlock;
+			}
+			if (__of_add_property(of_symbols, new_prop)) {
+				kfree(new_prop->name);
+				kfree(new_prop->value);
+				kfree(new_prop);
+				/* "name" auto-generated by unflatten */
+				if (!strcmp(prop->name, "name"))
+					continue;
+				unittest(0, "duplicate property '%s' in overlay_base node __symbols__",
+					 prop->name);
+				goto err_unlock;
+			}
+			if (__of_add_property_sysfs(of_symbols, new_prop)) {
+				unittest(0, "unable to add property '%s' in overlay_base node __symbols__ to sysfs",
+					 prop->name);
+				goto err_unlock;
+			}
+		}
+	}
+
+	mutex_unlock(&of_mutex);
+
+
+	/* now do the normal overlay usage test */
+
+	/* ---  overlay  --- */
+
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/substation@100/status");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/fairway-1/status");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/fairway-1/ride@100/track@30/incline-up");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/fairway-1/ride@100/track@40/incline-up");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/lights@40000/status");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/lights@40000/color");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/lights@40000/rate");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /__symbols__/hvac_2");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /__symbols__/ride_200");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /__symbols__/ride_200_left");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /__symbols__/ride_200_right");
+
+	ret = overlay_data_apply("overlay", NULL);
+
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /__symbols__/ride_200_right");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /__symbols__/ride_200_left");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /__symbols__/ride_200");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /__symbols__/hvac_2");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/lights@40000/rate");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/lights@40000/color");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/lights@40000/status");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/fairway-1/ride@100/track@40/incline-up");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/fairway-1/ride@100/track@30/incline-up");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/fairway-1/status");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: WARNING: memory leak will occur if overlay removed, property: /testcase-data-2/substation@100/status");
+
+	unittest(ret, "Adding overlay 'overlay' failed\n");
+
+	/* ---  overlay_bad_add_dup_node  --- */
+
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: ERROR: multiple fragments add and/or delete node /testcase-data-2/substation@100/motor-1/controller");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: ERROR: multiple fragments add, update, and/or delete property /testcase-data-2/substation@100/motor-1/controller/name");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: changeset: apply failed: REMOVE_PROPERTY /testcase-data-2/substation@100/motor-1/controller:name");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: Error reverting changeset (-19)");
+
+	unittest(overlay_data_apply("overlay_bad_add_dup_node", NULL),
+		 "Adding overlay 'overlay_bad_add_dup_node' failed\n");
+
+	EXPECT_END(KERN_ERR,
+		   "OF: Error reverting changeset (-19)");
+	EXPECT_END(KERN_ERR,
+		   "OF: changeset: apply failed: REMOVE_PROPERTY /testcase-data-2/substation@100/motor-1/controller:name");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: ERROR: multiple fragments add, update, and/or delete property /testcase-data-2/substation@100/motor-1/controller/name");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: ERROR: multiple fragments add and/or delete node /testcase-data-2/substation@100/motor-1/controller");
+
+	/* ---  overlay_bad_add_dup_prop  --- */
+
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: ERROR: multiple fragments add and/or delete node /testcase-data-2/substation@100/motor-1/electric");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: ERROR: multiple fragments add, update, and/or delete property /testcase-data-2/substation@100/motor-1/electric/rpm_avail");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: overlay: ERROR: multiple fragments add, update, and/or delete property /testcase-data-2/substation@100/motor-1/electric/name");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: changeset: apply failed: REMOVE_PROPERTY /testcase-data-2/substation@100/motor-1/electric:name");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: Error reverting changeset (-19)");
+
+	unittest(overlay_data_apply("overlay_bad_add_dup_prop", NULL),
+		 "Adding overlay 'overlay_bad_add_dup_prop' failed\n");
+
+	EXPECT_END(KERN_ERR,
+		   "OF: Error reverting changeset (-19)");
+	EXPECT_END(KERN_ERR,
+		   "OF: changeset: apply failed: REMOVE_PROPERTY /testcase-data-2/substation@100/motor-1/electric:name");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: ERROR: multiple fragments add, update, and/or delete property /testcase-data-2/substation@100/motor-1/electric/name");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: ERROR: multiple fragments add, update, and/or delete property /testcase-data-2/substation@100/motor-1/electric/rpm_avail");
+	EXPECT_END(KERN_ERR,
+		   "OF: overlay: ERROR: multiple fragments add and/or delete node /testcase-data-2/substation@100/motor-1/electric");
+
+	/* ---  overlay_bad_phandle  --- */
+
+	unittest(overlay_data_apply("overlay_bad_phandle", NULL),
+		 "Adding overlay 'overlay_bad_phandle' failed\n");
+
+	/* ---  overlay_bad_symbol  --- */
+
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: changeset: apply failed: REMOVE_PROPERTY /testcase-data-2/substation@100/hvac-medium-2:name");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: Error reverting changeset (-19)");
+
+	unittest(overlay_data_apply("overlay_bad_symbol", NULL),
+		 "Adding overlay 'overlay_bad_symbol' failed\n");
+
+	EXPECT_END(KERN_ERR,
+		   "OF: Error reverting changeset (-19)");
+	EXPECT_END(KERN_ERR,
+		   "OF: changeset: apply failed: REMOVE_PROPERTY /testcase-data-2/substation@100/hvac-medium-2:name");
+
+	/* ---  overlay_bad_unresolved  --- */
+
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: resolver: node label 'this_label_does_not_exist' not found in live devicetree symbols table");
+	EXPECT_BEGIN(KERN_ERR,
+		     "OF: resolver: overlay phandle fixup failed: -22");
+
+	unittest(overlay_data_apply("overlay_bad_unresolved", NULL),
+		 "Adding overlay 'overlay_bad_unresolved' failed\n");
+
+	EXPECT_END(KERN_ERR,
+		   "OF: resolver: overlay phandle fixup failed: -22");
+	EXPECT_END(KERN_ERR,
+		   "OF: resolver: node label 'this_label_does_not_exist' not found in live devicetree symbols table");
+
+	return;
+
+err_unlock:
+	mutex_unlock(&of_mutex);
+}
+
+static int of_unittest_pci_dev_num;
+static int of_unittest_pci_child_num;
+
+/*
+ * PCI device tree node test driver
+ */
+static const struct pci_device_id testdrv_pci_ids[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_REDHAT, 0x5), }, /* PCI_VENDOR_ID_REDHAT */
+	{ 0, }
+};
+
+static int testdrv_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	struct overlay_info *info;
+	struct device_node *dn;
+	int ret, ovcs_id;
+	u32 size;
+
+	dn = pdev->dev.of_node;
+	if (!dn) {
+		dev_err(&pdev->dev, "does not find bus endpoint");
+		return -EINVAL;
+	}
+
+	for (info = overlays; info && info->name; info++) {
+		if (!strcmp(info->name, "overlay_pci_node"))
+			break;
+	}
+	if (!info || !info->name) {
+		dev_err(&pdev->dev, "no overlay data for overlay_pci_node");
+		return -ENODEV;
+	}
+
+	size = info->dtbo_end - info->dtbo_begin;
+	ret = of_overlay_fdt_apply(info->dtbo_begin, size, &ovcs_id, dn);
+	of_node_put(dn);
+	if (ret)
+		return ret;
+
+	of_platform_default_populate(dn, NULL, &pdev->dev);
+	pci_set_drvdata(pdev, (void *)(uintptr_t)ovcs_id);
+
+	return 0;
+}
+
+static void testdrv_remove(struct pci_dev *pdev)
+{
+	int ovcs_id = (int)(uintptr_t)pci_get_drvdata(pdev);
+
+	of_platform_depopulate(&pdev->dev);
+	of_overlay_remove(&ovcs_id);
+}
+
+static struct pci_driver testdrv_driver = {
+	.name = "pci_dt_testdrv",
+	.id_table = testdrv_pci_ids,
+	.probe = testdrv_probe,
+	.remove = testdrv_remove,
+};
+
+static int unittest_pci_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct device *dev;
+	u64 exp_addr;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	dev = &pdev->dev;
+	while (dev && !dev_is_pci(dev))
+		dev = dev->parent;
+	if (!dev) {
+		pr_err("unable to find parent device\n");
+		return -ENODEV;
+	}
+
+	exp_addr = pci_resource_start(to_pci_dev(dev), 0) + 0x100;
+	unittest(res->start == exp_addr, "Incorrect translated address %llx, expected %llx\n",
+		 (u64)res->start, exp_addr);
+
+	of_unittest_pci_child_num++;
+
+	return 0;
+}
+
+static const struct of_device_id unittest_pci_of_match[] = {
+	{ .compatible = "unittest-pci" },
+	{ }
+};
+
+static struct platform_driver unittest_pci_driver = {
+	.probe = unittest_pci_probe,
+	.driver = {
+		.name = "unittest-pci",
+		.of_match_table = unittest_pci_of_match,
+	},
+};
+
+static int of_unittest_pci_node_verify(struct pci_dev *pdev, bool add)
+{
+	struct device_node *pnp, *np = NULL;
+	struct device *child_dev;
+	char *path = NULL;
+	const __be32 *reg;
+	int rc = 0;
+
+	pnp = pdev->dev.of_node;
+	unittest(pnp, "Failed creating PCI dt node\n");
+	if (!pnp)
+		return -ENODEV;
+
+	if (add) {
+		path = kasprintf(GFP_KERNEL, "%pOF/pci-ep-bus@0/unittest-pci@100", pnp);
+		np = of_find_node_by_path(path);
+		unittest(np, "Failed to get unittest-pci node under PCI node\n");
+		if (!np) {
+			rc = -ENODEV;
+			goto failed;
+		}
+
+		reg = of_get_property(np, "reg", NULL);
+		unittest(reg, "Failed to get reg property\n");
+		if (!reg)
+			rc = -ENODEV;
+	} else {
+		path = kasprintf(GFP_KERNEL, "%pOF/pci-ep-bus@0", pnp);
+		np = of_find_node_by_path(path);
+		unittest(!np, "Child device tree node is not removed\n");
+		child_dev = device_find_any_child(&pdev->dev);
+		unittest(!child_dev, "Child device is not removed\n");
+	}
+
+failed:
+	kfree(path);
+	if (np)
+		of_node_put(np);
+
+	return rc;
+}
+
+static void __init of_unittest_pci_node(void)
+{
+	struct pci_dev *pdev = NULL;
+	int rc;
+
+	if (!IS_ENABLED(CONFIG_PCI_DYNAMIC_OF_NODES))
+		return;
+
+	rc = pci_register_driver(&testdrv_driver);
+	unittest(!rc, "Failed to register pci test driver; rc = %d\n", rc);
+	if (rc)
+		return;
+
+	rc = platform_driver_register(&unittest_pci_driver);
+	if (unittest(!rc, "Failed to register unittest pci driver\n")) {
+		pci_unregister_driver(&testdrv_driver);
+		return;
+	}
+
+	while ((pdev = pci_get_device(PCI_VENDOR_ID_REDHAT, 0x5, pdev)) != NULL) {
+		of_unittest_pci_node_verify(pdev, true);
+		of_unittest_pci_dev_num++;
+	}
+	if (pdev)
+		pci_dev_put(pdev);
+
+	unittest(of_unittest_pci_dev_num,
+		 "No test PCI device been found. Please run QEMU with '-device pci-testdev'\n");
+	unittest(of_unittest_pci_dev_num == of_unittest_pci_child_num,
+		 "Child device number %d is not expected %d", of_unittest_pci_child_num,
+		 of_unittest_pci_dev_num);
+
+	platform_driver_unregister(&unittest_pci_driver);
+	pci_unregister_driver(&testdrv_driver);
+
+	while ((pdev = pci_get_device(PCI_VENDOR_ID_REDHAT, 0x5, pdev)) != NULL)
+		of_unittest_pci_node_verify(pdev, false);
+	if (pdev)
+		pci_dev_put(pdev);
+}
+#else
+
+static inline __init void of_unittest_overlay_high_level(void) {}
+static inline __init void of_unittest_pci_node(void) { }
+
+#endif
+
+static int __init of_unittest(void)
+{
+	struct device_node *np;
+	int res;
+
+	pr_info("start of unittest - you will see error messages\n");
+
+	/* Taint the kernel so we know we've run tests. */
+	add_taint(TAINT_TEST, LOCKDEP_STILL_OK);
+
+	/* adding data for unittest */
+
+	if (IS_ENABLED(CONFIG_UML))
+		unittest_unflatten_overlay_base();
+
+	res = unittest_data_add();
+	if (res)
+		return res;
+	if (!of_aliases)
+		of_aliases = of_find_node_by_path("/aliases");
+
+	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+	if (!np) {
+		pr_info("No testcase data in device tree; not running tests\n");
+		return 0;
+	}
+	of_node_put(np);
+
+	of_unittest_check_tree_linkage();
+	of_unittest_check_phandles();
+	of_unittest_find_node_by_name();
+	of_unittest_dynamic();
+	of_unittest_parse_phandle_with_args();
+	of_unittest_parse_phandle_with_args_map();
+	of_unittest_printf();
+	of_unittest_property_string();
+	of_unittest_property_copy();
+	of_unittest_changeset();
+	of_unittest_parse_interrupts();
+	of_unittest_parse_interrupts_extended();
+	of_unittest_dma_get_max_cpu_address();
+	of_unittest_parse_dma_ranges();
+	of_unittest_pci_dma_ranges();
+	of_unittest_bus_ranges();
+	of_unittest_bus_3cell_ranges();
+	of_unittest_reg();
+	of_unittest_match_node();
+	of_unittest_platform_populate();
+	of_unittest_overlay();
+	of_unittest_lifecycle();
+	of_unittest_pci_node();
+
+	/* Double check linkage after removing testcase data */
+	of_unittest_check_tree_linkage();
+
+	of_unittest_overlay_high_level();
+
+	pr_info("end of unittest - %i passed, %i failed\n",
+		unittest_results.passed, unittest_results.failed);
+
+	return 0;
+}
+late_initcall(of_unittest);