// 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