/*
   * Copyright (C) 2012 Kent Yoder IBM Corporation
   *
   * HWRNG interfaces to pull RNG data from a TPM
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
   */
  
  #include <linux/module.h>
  #include <linux/hw_random.h>
  #include <linux/tpm.h>
  
  #define MODULE_NAME "tpm-rng"
  
  static int tpm_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
  {
  	return tpm_get_random(TPM_ANY_NUM, data, max);
  }
  
  static struct hwrng tpm_rng = {
  	.name = MODULE_NAME,
  	.read = tpm_rng_read,
  };
  
  static int __init rng_init(void)
  {
  	return hwrng_register(&tpm_rng);
  }
  module_init(rng_init);
  
  static void __exit rng_exit(void)
  {
  	hwrng_unregister(&tpm_rng);
  }
  module_exit(rng_exit);
  
  MODULE_LICENSE("GPL v2");
  MODULE_AUTHOR("Kent Yoder <key@linux.vnet.ibm.com>");
  MODULE_DESCRIPTION("RNG driver for TPM devices");