linux_kernel/arch/arm/mach-tango/pm.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/init.h>
#include <linux/suspend.h>
#include <asm/suspend.h>
#include "smc.h"

static int tango_pm_powerdown(unsigned long arg)
{
	tango_suspend(__pa_symbol(cpu_resume));

	return -EIO; /* tango_suspend has failed */
}

static int tango_pm_enter(suspend_state_t state)
{
	if (state == PM_SUSPEND_MEM)
		return cpu_suspend(0, tango_pm_powerdown);

	return -EINVAL;
}

static const struct platform_suspend_ops tango_pm_ops = {
	.enter = tango_pm_enter,
	.valid = suspend_valid_only_mem,
};

static int __init tango_pm_init(void)
{
	suspend_set_ops(&tango_pm_ops);
	return 0;
}

late_initcall(tango_pm_init);