LXR linux/drivers/power/reset/restart-poweroff.c

   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 <asm/system_misc.h>
  19
  20static void restart_poweroff_do_poweroff(void)
  21{
  22        arm_pm_restart('h', NULL);
  23}
  24
  25static int restart_poweroff_probe(struct platform_device *pdev)
  26{
  27        /* If a pm_power_off function has already been added, leave it alone */
  28        if (pm_power_off != NULL) {
  29                dev_err(&pdev->dev,
  30                        "pm_power_off function already registered");
  31                return -EBUSY;
  32        }
  33
  34        pm_power_off = &restart_poweroff_do_poweroff;
  35        return 0;
  36}
  37
  38static int restart_poweroff_remove(struct platform_device *pdev)
  39{
  40        if (pm_power_off == &restart_poweroff_do_poweroff)
  41                pm_power_off = NULL;
  42
  43        return 0;
  44}
  45
  46static const struct of_device_id of_restart_poweroff_match[] = {
  47        { .compatible = "restart-poweroff", },
  48        {},
  49};
  50
  51static struct platform_driver restart_poweroff_driver = {
  52        .probe = restart_poweroff_probe,
  53        .remove = restart_poweroff_remove,
  54        .driver = {
  55                .name = "poweroff-restart",
  56                .owner = THIS_MODULE,
  57                .of_match_table = of_restart_poweroff_match,
  58        },
  59};
  60module_platform_driver(restart_poweroff_driver);
  61
  62MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch");
  63MODULE_DESCRIPTION("restart poweroff driver");
  64MODULE_LICENSE("GPLv2");
  65MODULE_ALIAS("platform:poweroff-restart");
  66