/*
  	Hardware Random Number Generator
  
  	Please read Documentation/hw_random.txt for details on use.
  
  	----------------------------------------------------------
  	This software may be used and distributed according to the terms
          of the GNU General Public License, incorporated herein by reference.
  
   */
  
  #ifndef LINUX_HWRANDOM_H_
  #define LINUX_HWRANDOM_H_
  
  #include <linux/types.h>
  #include <linux/list.h>
  
  /**
   * struct hwrng - Hardware Random Number Generator driver
   * @name:		Unique RNG name.
   * @init:		Initialization callback (can be NULL).
   * @cleanup:		Cleanup callback (can be NULL).
   * @data_present:	Callback to determine if data is available
   *			on the RNG. If NULL, it is assumed that
   *			there is always data available.  *OBSOLETE*
   * @data_read:		Read data from the RNG device.
   *			Returns the number of lower random bytes in "data".
   *			Must not be NULL.    *OBSOLETE*
   * @read:		New API. drivers can fill up to max bytes of data
   *			into the buffer. The buffer is aligned for any type.
   * @priv:		Private data, for use by the RNG driver.
   */
  struct hwrng {
  	const char *name;
  	int (*init)(struct hwrng *rng);
  	void (*cleanup)(struct hwrng *rng);
  	int (*data_present)(struct hwrng *rng, int wait);
  	int (*data_read)(struct hwrng *rng, u32 *data);
  	int (*read)(struct hwrng *rng, void *data, size_t max, bool wait);
  	unsigned long priv;
  
  	/* internal. */
  	struct list_head list;
  };
  
  /** Register a new Hardware Random Number Generator driver. */
  extern int hwrng_register(struct hwrng *rng);
  /** Unregister a Hardware Random Number Generator driver. */
  extern void hwrng_unregister(struct hwrng *rng);
  
  #endif /* LINUX_HWRANDOM_H_ */