1/*
2 * poweroff.c - sysrq handler to gracefully power down machine.
3 *
4 * This file is released under the GPL v2
5 */
6
7#include <linux/kernel.h>
8#include <linux/sysrq.h>
9#include <linux/init.h>
10#include <linux/pm.h>
11#include <linux/workqueue.h>
12#include <linux/reboot.h>
13#include <linux/cpumask.h>
14
15/*
16 * When the user hits Sys-Rq o to power down the machine this is the
17 * callback we use.
18 */
19
20static void do_poweroff(struct work_struct *dummy)
21{
22	kernel_power_off();
23}
24
25static DECLARE_WORK(poweroff_work, do_poweroff);
26
27static void handle_poweroff(int key)
28{
29	/* run sysrq poweroff on boot cpu */
30	schedule_work_on(cpumask_first(cpu_online_mask), &poweroff_work);
31}
32
33static struct sysrq_key_op	sysrq_poweroff_op = {
34	.handler        = handle_poweroff,
35	.help_msg       = "poweroff(o)",
36	.action_msg     = "Power Off",
37	.enable_mask	= SYSRQ_ENABLE_BOOT,
38};
39
40static int __init pm_sysrq_init(void)
41{
42	register_sysrq_key('o', &sysrq_poweroff_op);
43	return 0;
44}
45
46subsys_initcall(pm_sysrq_init);
47