/*
   * OF helpers for regulator framework
   *
   * Copyright (C) 2011 Texas Instruments, Inc.
   * Rajendra Nayak <rnayak@ti.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/module.h>

  #include <linux/slab.h>
  #include <linux/of.h>
  #include <linux/regulator/machine.h>
  
  static void of_get_regulation_constraints(struct device_node *np,
  					struct regulator_init_data **init_data)
  {
  	const __be32 *min_uV, *max_uV, *uV_offset;
  	const __be32 *min_uA, *max_uA;
  	struct regulation_constraints *constraints = &(*init_data)->constraints;
  
  	constraints->name = of_get_property(np, "regulator-name", NULL);
  
  	min_uV = of_get_property(np, "regulator-min-microvolt", NULL);
  	if (min_uV)
  		constraints->min_uV = be32_to_cpu(*min_uV);
  	max_uV = of_get_property(np, "regulator-max-microvolt", NULL);
  	if (max_uV)
  		constraints->max_uV = be32_to_cpu(*max_uV);
  
  	/* Voltage change possible? */
  	if (constraints->min_uV != constraints->max_uV)
  		constraints->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;

  	/* Only one voltage?  Then make sure it's set. */
  	if (constraints->min_uV == constraints->max_uV)
  		constraints->apply_uV = true;

  
  	uV_offset = of_get_property(np, "regulator-microvolt-offset", NULL);
  	if (uV_offset)
  		constraints->uV_offset = be32_to_cpu(*uV_offset);
  	min_uA = of_get_property(np, "regulator-min-microamp", NULL);
  	if (min_uA)
  		constraints->min_uA = be32_to_cpu(*min_uA);
  	max_uA = of_get_property(np, "regulator-max-microamp", NULL);
  	if (max_uA)
  		constraints->max_uA = be32_to_cpu(*max_uA);
  
  	/* Current change possible? */
  	if (constraints->min_uA != constraints->max_uA)
  		constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;
  
  	if (of_find_property(np, "regulator-boot-on", NULL))
  		constraints->boot_on = true;
  
  	if (of_find_property(np, "regulator-always-on", NULL))
  		constraints->always_on = true;
  	else /* status change should be possible if not always on. */
  		constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;
  }
  
  /**
   * of_get_regulator_init_data - extract regulator_init_data structure info
   * @dev: device requesting for regulator_init_data
   *
   * Populates regulator_init_data structure by extracting data from device
   * tree node, returns a pointer to the populated struture or NULL if memory
   * alloc fails.
   */

  struct regulator_init_data *of_get_regulator_init_data(struct device *dev,
  						struct device_node *node)

  {
  	struct regulator_init_data *init_data;

  	if (!node)

  		return NULL;
  
  	init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL);
  	if (!init_data)
  		return NULL; /* Out of memory? */

  	of_get_regulation_constraints(node, &init_data);

  	return init_data;
  }

  EXPORT_SYMBOL_GPL(of_get_regulator_init_data);