kernel/power/poweroff.c

   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
  14 /*
  15  * When the user hits Sys-Rq o to power down the machine this is the
  16  * callback we use.
  17  */
  18
  19 static void do_poweroff(void *dummy)
  20 {
  21         kernel_power_off();
  22 }
  23
  24 static DECLARE_WORK(poweroff_work, do_poweroff, NULL);
  25
  26 static void handle_poweroff(int key, struct tty_struct *tty)
  27 {
  28         schedule_work(&poweroff_work);
  29 }
  30
  31 static struct sysrq_key_op      sysrq_poweroff_op = {
  32         .handler        = handle_poweroff,
  33         .help_msg       = "powerOff",
  34         .action_msg     = "Power Off",
  35         .enable_mask    = SYSRQ_ENABLE_BOOT,
  36 };
  37
  38 static int pm_sysrq_init(void)
  39 {
  40         register_sysrq_key('o', &sysrq_poweroff_op);
  41         return 0;
  42 }
  43
  44 subsys_initcall(pm_sysrq_init);