linux/kernel/power/suspend_test.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * kernel/power/suspend_test.c - Suspend to RAM and standby test facility.
 *
 * Copyright (c) 2009 Pavel Machek <[email protected]>
 */

#include <linux/init.h>
#include <linux/rtc.h>

#include "power.h"

/*
 * We test the system suspend code by setting an RTC wakealarm a short
 * time in the future, then suspending.  Suspending the devices won't
 * normally take long ... some systems only need a few milliseconds.
 *
 * The time it takes is system-specific though, so when we test this
 * during system bootup we allow a LOT of time.
 */
#define TEST_SUSPEND_SECONDS …

static unsigned long suspend_test_start_time;
static u32 test_repeat_count_max = …;
static u32 test_repeat_count_current;

void suspend_test_start(void)
{ … }

void suspend_test_finish(const char *label)
{ … }

/*
 * To test system suspend, we need a hands-off mechanism to resume the
 * system.  RTCs wake alarms are a common self-contained mechanism.
 */

static void __init test_wakealarm(struct rtc_device *rtc, suspend_state_t state)
{ … }

static int __init has_wakealarm(struct device *dev, const void *data)
{ … }

/*
 * Kernel options like "test_suspend=mem" force suspend/resume sanity tests
 * at startup time.  They're normally disabled, for faster boot and because
 * we can't know which states really work on this particular system.
 */
static const char *test_state_label __initdata;

static char warn_bad_state[] __initdata = …;

static int __init setup_test_suspend(char *value)
{ … }
__setup(…);

static int __init test_suspend(void)
{ … }
late_initcall(test_suspend);