// 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(u8 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);