/*
   * Copyright (c) 2011 The Chromium OS Authors.
   *

   * SPDX-License-Identifier:	GPL-2.0+

   */
  
  #ifndef __TIS_H
  #define __TIS_H
  
  #include <common.h>
  
  /* Low-level interface to access TPM */
  
  /*
   * tis_init()
   *
   * Initialize the TPM device. Returns 0 on success or -1 on
   * failure (in case device probing did not succeed).
   */
  int tis_init(void);
  
  /*
   * tis_open()
   *
   * Requests access to locality 0 for the caller. After all commands have been
   * completed the caller is supposed to call tis_close().
   *
   * Returns 0 on success, -1 on failure.
   */
  int tis_open(void);
  
  /*
   * tis_close()
   *
   * terminate the currect session with the TPM by releasing the locked
   * locality. Returns 0 on success of -1 on failure (in case lock
   * removal did not succeed).
   */
  int tis_close(void);
  
  /*
   * tis_sendrecv()
   *
   * Send the requested data to the TPM and then try to get its response
   *
   * @sendbuf - buffer of the data to send
   * @send_size size of the data to send
   * @recvbuf - memory to save the response to
   * @recv_len - pointer to the size of the response buffer
   *
   * Returns 0 on success (and places the number of response bytes at recv_len)
   * or -1 on failure.
   */
  int tis_sendrecv(const uint8_t *sendbuf, size_t send_size, uint8_t *recvbuf,
  			size_t *recv_len);
  
  #endif /* __TIS_H */