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 | |
19 | static void do_poweroff(struct work_struct *dummy) |
20 | { |
21 | kernel_power_off(); |
22 | } |
23 | |
24 | static DECLARE_WORK(poweroff_work, do_poweroff); |
25 | |
26 | static void handle_poweroff(u8 key) |
27 | { |
28 | /* run sysrq poweroff on boot cpu */ |
29 | schedule_work_on(cpu: cpumask_first(cpu_online_mask), work: &poweroff_work); |
30 | } |
31 | |
32 | static 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 | |
39 | static int __init pm_sysrq_init(void) |
40 | { |
41 | register_sysrq_key(key: 'o', op: &sysrq_poweroff_op); |
42 | return 0; |
43 | } |
44 | |
45 | subsys_initcall(pm_sysrq_init); |
46 |