poweroff.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* poweroff.c - sysrq handler to gracefully power down machine.
*/
#include <linux/kernel.h>
#include <linux/sysrq.h>
#include <linux/init.h>
#include <linux/pm.h>
#include <linux/workqueue.h>
#include <linux/reboot.h>
#include <linux/cpumask.h>
/*
* When the user hits Sys-Rq o to power down the machine this is the
* callback we use.
*/
static void do_poweroff(struct work_struct *dummy)
{
kernel_power_off();
}
static DECLARE_WORK(poweroff_work, do_poweroff);
static void handle_poweroff(int key)
{
/* run sysrq poweroff on boot cpu */
schedule_work_on(cpumask_first(cpu_online_mask), &poweroff_work);
}
static const struct sysrq_key_op sysrq_poweroff_op = {
.handler = handle_poweroff,
.help_msg = "poweroff(o)",
.action_msg = "Power Off",
.enable_mask = SYSRQ_ENABLE_BOOT,
};
static int __init pm_sysrq_init(void)
{
register_sysrq_key('o', &sysrq_poweroff_op);
return 0;
}
subsys_initcall(pm_sysrq_init);