Regulator Driver Interface
  ==========================
  
  The regulator driver interface is relatively simple and designed to allow
  regulator drivers to register their services with the core framework.
  
  
  Registration
  ============
  
  Drivers can register a regulator by calling :-

  struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc,
  	struct device *dev, struct regulator_init_data *init_data,

  	void *driver_data, struct device_node *of_node);

  This will register the regulators capabilities and operations to the regulator
  core.

  
  Regulators can be unregistered by calling :-
  
  void regulator_unregister(struct regulator_dev *rdev);
  
  
  Regulator Events
  ================
  Regulators can send events (e.g. over temp, under voltage, etc) to consumer
  drivers by calling :-
  
  int regulator_notifier_call_chain(struct regulator_dev *rdev,
  				  unsigned long event, void *data);