text: /*
   * Suspend/resume support
   *
   * Copyright 2009  MontaVista Software, Inc.
   *
   * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   */
  
  #include <linux/init.h>
  #include <linux/types.h>
  #include <linux/errno.h>
  #include <linux/suspend.h>
  #include <linux/delay.h>
  #include <linux/device.h>
  #include <linux/of_platform.h>
  
  struct pmc_regs {
  	__be32 devdisr;
  	__be32 devdisr2;
  	__be32 :32;
  	__be32 :32;
  	__be32 pmcsr;
  #define PMCSR_SLP	(1 << 17)
  };
  
  static struct device *pmc_dev;
  static struct pmc_regs __iomem *pmc_regs;
  
  static int pmc_suspend_enter(suspend_state_t state)
  {
  	int ret;
  
  	setbits32(&pmc_regs->pmcsr, PMCSR_SLP);
  	/* At this point, the CPU is asleep. */
  
  	/* Upon resume, wait for SLP bit to be clear. */
  	ret = spin_event_timeout((in_be32(&pmc_regs->pmcsr) & PMCSR_SLP) == 0,
  				 10000, 10) ? 0 : -ETIMEDOUT;
  	if (ret)
  		dev_err(pmc_dev, "tired waiting for SLP bit to clear\n");
  	return ret;
  }
  
  static int pmc_suspend_valid(suspend_state_t state)
  {
  	if (state != PM_SUSPEND_STANDBY)
  		return 0;
  	return 1;
  }
  
  static struct platform_suspend_ops pmc_suspend_ops = {
  	.valid = pmc_suspend_valid,
  	.enter = pmc_suspend_enter,
  };
  
  static int pmc_probe(struct platform_device *ofdev,
  		     const struct of_device_id *id)
  {
  	pmc_regs = of_iomap(ofdev->dev.of_node, 0);
  	if (!pmc_regs)
  		return -ENOMEM;
  
  	pmc_dev = &ofdev->dev;
  	suspend_set_ops(&pmc_suspend_ops);
  	return 0;
  }
  
  static const struct of_device_id pmc_ids[] = {
  	{ .compatible = "fsl,mpc8548-pmc", },
  	{ .compatible = "fsl,mpc8641d-pmc", },
  	{ },
  };
  
  static struct of_platform_driver pmc_driver = {
  	.driver = {
  		.name = "fsl-pmc",
  		.owner = THIS_MODULE,
  		.of_match_table = pmc_ids,
  	},
  	.probe = pmc_probe,
  };
  
  static int __init pmc_init(void)
  {
  	return of_register_platform_driver(&pmc_driver);
  }
  device_initcall(pmc_init);
  