xref: /linux/drivers/power/reset/restart-poweroff.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * Power off by restarting and let u-boot keep hold of the machine
3  * until the user presses a button for example.
4  *
5  * Andrew Lunn <andrew@lunn.ch>
6  *
7  * Copyright (C) 2012 Andrew Lunn
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/platform_device.h>
16 #include <linux/of_platform.h>
17 #include <linux/module.h>
18 #include <linux/reboot.h>
19 
20 static void restart_poweroff_do_poweroff(void)
21 {
22 	reboot_mode = REBOOT_HARD;
23 	machine_restart(NULL);
24 }
25 
26 static int restart_poweroff_probe(struct platform_device *pdev)
27 {
28 	/* If a pm_power_off function has already been added, leave it alone */
29 	if (pm_power_off != NULL) {
30 		dev_err(&pdev->dev,
31 			"pm_power_off function already registered");
32 		return -EBUSY;
33 	}
34 
35 	pm_power_off = &restart_poweroff_do_poweroff;
36 	return 0;
37 }
38 
39 static int restart_poweroff_remove(struct platform_device *pdev)
40 {
41 	if (pm_power_off == &restart_poweroff_do_poweroff)
42 		pm_power_off = NULL;
43 
44 	return 0;
45 }
46 
47 static const struct of_device_id of_restart_poweroff_match[] = {
48 	{ .compatible = "restart-poweroff", },
49 	{},
50 };
51 
52 static struct platform_driver restart_poweroff_driver = {
53 	.probe = restart_poweroff_probe,
54 	.remove = restart_poweroff_remove,
55 	.driver = {
56 		.name = "poweroff-restart",
57 		.of_match_table = of_restart_poweroff_match,
58 	},
59 };
60 module_platform_driver(restart_poweroff_driver);
61 
62 MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch");
63 MODULE_DESCRIPTION("restart poweroff driver");
64 MODULE_LICENSE("GPL v2");
65 MODULE_ALIAS("platform:poweroff-restart");
66