1. 根目录:
2. drivers
3. of
4. selftest.c

/*
 * Self tests for device tree subsystem
 */

#define pr_fmt(fmt) "### %s(): " fmt, __func__

#include <linux/clk.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/device.h>

static bool selftest_passed = true;
#define selftest(result, fmt, ...) { \
	selftest_passed &= (result); \
	if (!(result)) \
		pr_err("FAIL %s:%i " fmt, __FILE__, __LINE__, ##__VA_ARGS__); \
}

static void __init of_selftest_parse_phandle_with_args(void)
{
	struct device_node *np;
	struct of_phandle_args args;
	int rc, i;
	bool passed_all = true;

	pr_info("start\n");
	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
	if (!np) {
		pr_err("missing testcase data\n");
		return;
	}

	for (i = 0; i < 7; i++) {
		bool passed = true;
		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 == -EINVAL);
			break;
		default:
			passed = false;
		}

		if (!passed) {
			int j;
			pr_err("index %i - data error on node %s rc=%i regs=[",
				i, args.np->full_name, rc);
			for (j = 0; j < args.args_count; j++)
				printk(" %i", args.args[j]);
			printk(" ]\n");

			passed_all = false;
		}
	}

	/* Check for missing list property */
	rc = of_parse_phandle_with_args(np, "phandle-list-missing",
					"#phandle-cells", 0, &args);
	passed_all &= (rc == -EINVAL);

	/* Check for missing cells property */
	rc = of_parse_phandle_with_args(np, "phandle-list",
					"#phandle-cells-missing", 0, &args);
	passed_all &= (rc == -EINVAL);

	/* Check for bad phandle in list */
	rc = of_parse_phandle_with_args(np, "phandle-list-bad-phandle",
					"#phandle-cells", 0, &args);
	passed_all &= (rc == -EINVAL);

	/* Check for incorrectly formed argument list */
	rc = of_parse_phandle_with_args(np, "phandle-list-bad-args",
					"#phandle-cells", 1, &args);
	passed_all &= (rc == -EINVAL);

	pr_info("end - %s\n", passed_all ? "PASS" : "FAIL");
}

static void __init of_selftest_property_match_string(void)
{
	struct device_node *np;
	int rc;

	pr_info("start\n");
	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");
	selftest(rc == 0, "first expected:0 got:%i\n", rc);
	rc = of_property_match_string(np, "phandle-list-names", "second");
	selftest(rc == 1, "second expected:0 got:%i\n", rc);
	rc = of_property_match_string(np, "phandle-list-names", "third");
	selftest(rc == 2, "third expected:0 got:%i\n", rc);
	rc = of_property_match_string(np, "phandle-list-names", "fourth");
	selftest(rc == -ENODATA, "unmatched string; rc=%i", rc);
	rc = of_property_match_string(np, "missing-property", "blah");
	selftest(rc == -EINVAL, "missing property; rc=%i", rc);
	rc = of_property_match_string(np, "empty-property", "blah");
	selftest(rc == -ENODATA, "empty property; rc=%i", rc);
	rc = of_property_match_string(np, "unterminated-string", "blah");
	selftest(rc == -EILSEQ, "unterminated string; rc=%i", rc);
}

static int __init of_selftest(void)
{
	struct device_node *np;

	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);

	pr_info("start of selftest - you will see error messages\n");
	of_selftest_parse_phandle_with_args();
	of_selftest_property_match_string();
	pr_info("end of selftest - %s\n", selftest_passed ? "PASS" : "FAIL");
	return 0;
}
late_initcall(of_selftest);