1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Power off by restarting and let u-boot keep hold of the machine
4  * until the user presses a button for example.
5  *
6  * Andrew Lunn <andrew@lunn.ch>
7  *
8  * Copyright (C) 2012 Andrew Lunn
9  */
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/platform_device.h>
13 #include <linux/of_platform.h>
14 #include <linux/module.h>
15 #include <linux/reboot.h>
16 
17 static void restart_poweroff_do_poweroff(void)
18 {
19 	reboot_mode = REBOOT_HARD;
20 	machine_restart(NULL);
21 }
22 
23 static int restart_poweroff_probe(struct platform_device *pdev)
24 {
25 	/* If a pm_power_off function has already been added, leave it alone */
26 	if (pm_power_off != NULL) {
27 		dev_err(&pdev->dev,
28 			"pm_power_off function already registered");
29 		return -EBUSY;
30 	}
31 
32 	pm_power_off = &restart_poweroff_do_poweroff;
33 	return 0;
34 }
35 
36 static int restart_poweroff_remove(struct platform_device *pdev)
37 {
38 	if (pm_power_off == &restart_poweroff_do_poweroff)
39 		pm_power_off = NULL;
40 
41 	return 0;
42 }
43 
44 static const struct of_device_id of_restart_poweroff_match[] = {
45 	{ .compatible = "restart-poweroff", },
46 	{},
47 };
48 MODULE_DEVICE_TABLE(of, of_restart_poweroff_match);
49 
50 static struct platform_driver restart_poweroff_driver = {
51 	.probe = restart_poweroff_probe,
52 	.remove = restart_poweroff_remove,
53 	.driver = {
54 		.name = "poweroff-restart",
55 		.of_match_table = of_restart_poweroff_match,
56 	},
57 };
58 module_platform_driver(restart_poweroff_driver);
59 
60 MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch");
61 MODULE_DESCRIPTION("restart poweroff driver");
62 MODULE_ALIAS("platform:poweroff-restart");
63