LXR linux/kernel/power/poweroff.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * poweroff.c - sysrq handler to gracefully power down machine.
   4 */
   5
   6#include <linux/kernel.h>
   7#include <linux/sysrq.h>
   8#include <linux/init.h>
   9#include <linux/pm.h>
  10#include <linux/workqueue.h>
  11#include <linux/reboot.h>
  12#include <linux/cpumask.h>
  13
  14/*
  15 * When the user hits Sys-Rq o to power down the machine this is the
  16 * callback we use.
  17 */
  18
  19static void do_poweroff(struct work_struct *dummy)
  20{
  21        kernel_power_off();
  22}
  23
  24static DECLARE_WORK(poweroff_work, do_poweroff);
  25
  26static void handle_poweroff(int key)
  27{
  28        /* run sysrq poweroff on boot cpu */
  29        schedule_work_on(cpumask_first(cpu_online_mask), &poweroff_work);
  30}
  31
  32static const struct sysrq_key_op        sysrq_poweroff_op = {
  33        .handler        = handle_poweroff,
  34        .help_msg       = "poweroff(o)",
  35        .action_msg     = "Power Off",
  36        .enable_mask    = SYSRQ_ENABLE_BOOT,
  37};
  38
  39static int __init pm_sysrq_init(void)
  40{
  41        register_sysrq_key('o', &sysrq_poweroff_op);
  42        return 0;
  43}
  44
  45subsys_initcall(pm_sysrq_init);
  46