path: root/drivers/char/tpm/tpm-interface.c

/*
 * Copyright (C) 2004 IBM Corporation
 *
 * Authors:
 * Leendert van Doorn <leendert@watson.ibm.com>
 * Dave Safford <safford@watson.ibm.com>
 * Reiner Sailer <sailer@watson.ibm.com>
 * Kylene Hall <kjhall@us.ibm.com>
 *
 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
 *
 * Device driver for TCG/TCPA TPM (trusted platform module).
 * Specifications at www.trustedcomputinggroup.org
 *
 * 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, version 2 of the
 * License.
 *
 * Note, the TPM chip is not interrupt driven (only polling)
 * and can have very long timeouts (minutes!). Hence the unusual
 * calls to msleep.
 *
 */

#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/freezer.h>

#include "tpm.h"
#include "tpm_eventlog.h"

#define TPM_MAX_ORDINAL 243
#define TSC_MAX_ORDINAL 12
#define TPM_PROTECTED_COMMAND 0x00
#define TPM_CONNECTION_COMMAND 0x40

/*
 * Bug workaround - some TPM's don't flush the most
 * recently changed pcr on suspend, so force the flush
 * with an extend to the selected _unused_ non-volatile pcr.
 */
static int tpm_suspend_pcr;
module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
MODULE_PARM_DESC(suspend_pcr,
		 "PCR to use for dummy writes to faciltate flush on suspend.");

static LIST_HEAD(tpm_chip_list);
static DEFINE_SPINLOCK(driver_lock);
static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);

/*
 * Array with one entry per ordinal defining the maximum amount
 * of time the chip could take to return the result.  The ordinal
 * designation of short, medium or long is defined in a table in
 * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
 * values of the SHORT, MEDIUM, and LONG durations are retrieved
 * from the chip during initialization with a call to tpm_get_timeouts.
 */
static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
	TPM_UNDEFINED,		/* 0 */
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,		/* 5 */
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_SHORT,		/* 10 */
	TPM_SHORT,
	TPM_MEDIUM,
	TPM_LONG,
	TPM_LONG,
	TPM_MEDIUM,		/* 15 */
	TPM_SHORT,
	TPM_SHORT,
	TPM_MEDIUM,
	TPM_LONG,
	TPM_SHORT,		/* 20 */
	TPM_SHORT,
	TPM_MEDIUM,
	TPM_MEDIUM,
	TPM_MEDIUM,
	TPM_SHORT,		/* 25 */
	TPM_SHORT,
	TPM_MEDIUM,
	TPM_SHORT,
	TPM_SHORT,
	TPM_MEDIUM,		/* 30 */
	TPM_LONG,
	TPM_MEDIUM,
	TPM_SHORT,
	TPM_SHORT,
	TPM_SHORT,		/* 35 */
	TPM_MEDIUM,
	TPM_MEDIUM,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_MEDIUM,		/* 40 */
	TPM_LONG,
	TPM_MEDIUM,
	TPM_SHORT,
	TPM_SHORT,
	TPM_SHORT,		/* 45 */
	TPM_SHORT,
	TPM_SHORT,
	TPM_SHORT,
	TPM_LONG,
	TPM_MEDIUM,		/* 50 */
	TPM_MEDIUM,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,		/* 55 */
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_MEDIUM,		/* 60 */
	TPM_MEDIUM,
	TPM_MEDIUM,
	TPM_SHORT,
	TPM_SHORT,
	TPM_MEDIUM,		/* 65 */
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_SHORT,		/* 70 */
	TPM_SHORT,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,		/* 75 */
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_LONG,		/* 80 */
	TPM_UNDEFINED,
	TPM_MEDIUM,
	TPM_LONG,
	TPM_SHORT,
	TPM_UNDEFINED,		/* 85 */
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_SHORT,		/* 90 */
	TPM_SHORT,
	TPM_SHORT,
	TPM_SHORT,
	TPM_SHORT,
	TPM_UNDEFINED,		/* 95 */
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_MEDIUM,		/* 100 */
	TPM_SHORT,
	TPM_SHORT,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,		/* 105 */
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_SHORT,		/* 110 */
	TPM_SHORT,
	TPM_SHORT,
	TPM_SHORT,
	TPM_SHORT,
	TPM_SHORT,		/* 115 */
	TPM_SHORT,
	TPM_SHORT,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_LONG,		/* 120 */
	TPM_LONG,
	TPM_MEDIUM,
	TPM_UNDEFINED,
	TPM_SHORT,
	TPM_SHORT,		/* 125 */
	TPM_SHORT,
	TPM_LONG,
	TPM_SHORT,
	TPM_SHORT,
	TPM_SHORT,		/* 130 */
	TPM_MEDIUM,
	TPM_UNDEFINED,
	TPM_SHORT,
	TPM_MEDIUM,
	TPM_UNDEFINED,		/* 135 */
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_UNDEFINED,
	TPM_SHORT,		/* 140 */
	TPM_SHORT,
	TPM_UNDEFINED