tpm: Rename tpm.c to tpm-interface.c

This is preparation for making the tpm module multi-file. kbuild does
not like having a .c file with the same name as a module. We wish to
keep the tpm module name so that userspace doesn't see this change.

tpm-interface.c is chosen because the next several commits in the series
migrate items into tpm-sysfs.c, tpm-dev.c and tpm-class.c. All that will
be left is tpm command processing and interfacing code.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>

1 files changed, 1554 insertions, 0 deletions

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
new file mode 100644
index 000000000000..6ae41d337630
--- /dev/null
+++ b/drivers/char/tpm/tpm-interface.c
@@ -0,0 +1,1554 @@
+/*
+ * 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"
+
+enum tpm_duration {
+	TPM_SHORT = 0,
+	TPM_MEDIUM = 1,
+	TPM_LONG = 2,
+	TPM_UNDEFINED,
+};
+
+#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,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,		/* 145 */
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_SHORT,		/* 150 */
+	TPM_MEDIUM,
+	TPM_MEDIUM,
+	TPM_SHORT,
+	TPM_SHORT,
+	TPM_UNDEFINED,		/* 155 */
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_SHORT,		/* 160 */
+	TPM_SHORT,
+	TPM_SHORT,
+	TPM_SHORT,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,		/* 165 */
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_LONG,		/* 170 */
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,		/* 175 */
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_MEDIUM,		/* 180 */
+	TPM_SHORT,
+	TPM_MEDIUM,
+	TPM_MEDIUM,
+	TPM_MEDIUM,
+	TPM_MEDIUM,		/* 185 */
+	TPM_SHORT,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,		/* 190 */
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,		/* 195 */
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_SHORT,		/* 200 */
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_SHORT,
+	TPM_SHORT,		/* 205 */
+	TPM_SHORT,
+	TPM_SHORT,
+	TPM_SHORT,
+	TPM_SHORT,
+	TPM_MEDIUM,		/* 210 */
+	TPM_UNDEFINED,
+	TPM_MEDIUM,
+	TPM_MEDIUM,
+	TPM_MEDIUM,
+	TPM_UNDEFINED,		/* 215 */
+	TPM_MEDIUM,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_SHORT,
+	TPM_SHORT,		/* 220 */
+	TPM_SHORT,
+	TPM_SHORT,
+	TPM_SHORT,
+	TPM_SHORT,
+	TPM_UNDEFINED,		/* 225 */
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_SHORT,		/* 230 */
+	TPM_LONG,
+	TPM_MEDIUM,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,		/* 235 */
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_UNDEFINED,
+	TPM_SHORT,		/* 240 */
+	TPM_UNDEFINED,
+	TPM_MEDIUM,
+};
+
+static void user_reader_timeout(unsigned long ptr)
+{
+	struct tpm_chip *chip = (struct tpm_chip *) ptr;
+
+	schedule_work(&chip->work);
+}
+
+static void timeout_work(struct work_struct *work)
+{
+	struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
+
+	mutex_lock(&chip->buffer_mutex);
+	atomic_set(&chip->data_pending, 0);
+	memset(chip->data_buffer, 0, TPM_BUFSIZE);
+	mutex_unlock(&chip->buffer_mutex);
+}
+
+/*
+ * Returns max number of jiffies to wait
+ */
+unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
+					   u32 ordinal)
+{
+	int duration_idx = TPM_UNDEFINED;
+	int duration = 0;
+	u8 category = (ordinal >> 24) & 0xFF;
+
+	if ((category == TPM_PROTECTED_COMMAND && ordinal < TPM_MAX_ORDINAL) ||
+	    (category == TPM_CONNECTION_COMMAND && ordinal < TSC_MAX_ORDINAL))
+		duration_idx = tpm_ordinal_duration[ordinal];
+
+	if (duration_idx != TPM_UNDEFINED)
+		duration = chip->vendor.duration[duration_idx];
+	if (duration <= 0)
+		return 2 * 60 * HZ;
+	else
+		return duration;
+}
+EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
+
+/*
+ * Internal kernel interface to transmit TPM commands
+ */
+static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
+			    size_t bufsiz)
+{
+	ssize_t rc;
+	u32 count, ordinal;
+	unsigned long stop;
+
+	if (bufsiz > TPM_BUFSIZE)
+		bufsiz = TPM_BUFSIZE;
+
+	count = be32_to_cpu(*((__be32 *) (buf + 2)));
+	ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
+	if (count == 0)
+		return -ENODATA;
+	if (count > bufsiz) {
+		dev_err(chip->dev,
+			"invalid count value %x %zx\n", count, bufsiz);
+		return -E2BIG;
+	}
+
+	mutex_lock(&chip->tpm_mutex);
+
+	rc = chip->vendor.send(chip, (u8 *) buf, count);
+	if (rc < 0) {
+		dev_err(chip->dev,
+			"tpm_transmit: tpm_send: error %zd\n", rc);
+		goto out;
+	}
+
+	if (chip->vendor.irq)
+		goto out_recv;
+
+	stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
+	do {
+		u8 status = chip->vendor.status(chip);
+		if ((status & chip->vendor.req_complete_mask) ==
+		    chip->vendor.req_complete_val)
+			goto out_recv;
+
+		if (chip->vendor.req_canceled(chip, status)) {
+			dev_err(chip->dev, "Operation Canceled\n");
+			rc = -ECANCELED;
+			goto out;
+		}
+
+		msleep(TPM_TIMEOUT);	/* CHECK */
+		rmb();
+	} while (time_before(jiffies, stop));
+
+	chip->vendor.cancel(chip);
+	dev_err(chip->dev, "Operation Timed out\n");
+	rc = -ETIME;
+	goto out;
+
+out_recv:
+	rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
+	if (rc < 0)
+		dev_err(chip->dev,
+			"tpm_transmit: tpm_recv: error %zd\n", rc);
+out:
+	mutex_unlock(&chip->tpm_mutex);
+	return rc;
+}
+
+#define TPM_DIGEST_SIZE 20
+#define TPM_RET_CODE_IDX 6
+
+enum tpm_capabilities {
+	TPM_CAP_FLAG = cpu_to_be32(4),
+	TPM_CAP_PROP = cpu_to_be32(5),
+	CAP_VERSION_1_1 = cpu_to_be32(0x06),
+	CAP_VERSION_1_2 = cpu_to_be32(0x1A)
+};
+
+enum tpm_sub_capabilities {
+	TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
+	TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
+	TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
+	TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
+	TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
+	TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
+	TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
+
+};
+
+static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
+			    int len, const char *desc)
+{
+	int err;
+
+	len = tpm_transmit(chip, (u8 *) cmd, len);
+	if (len <  0)
+		return len;
+	else if (len < TPM_HEADER_SIZE)
+		return -EFAULT;
+
+	err = be32_to_cpu(cmd->header.out.return_code);
+	if (err != 0 && desc)
+		dev_err(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
+
+	return err;
+}
+
+#define TPM_INTERNAL_RESULT_SIZE 200
+#define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
+#define TPM_ORD_GET_CAP cpu_to_be32(101)
+#define TPM_ORD_GET_RANDOM cpu_to_be32(70)
+
+static const struct tpm_input_header tpm_getcap_header = {
+	.tag = TPM_TAG_RQU_COMMAND,
+	.length = cpu_to_be32(22),
+	.ordinal = TPM_ORD_GET_CAP
+};
+
+ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
+		   const char *desc)
+{
+	struct tpm_cmd_t tpm_cmd;
+	int rc;
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+
+	tpm_cmd.header.in = tpm_getcap_header;
+	if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
+		tpm_cmd.params.getcap_in.cap = subcap_id;
+		/*subcap field not necessary */
+		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
+		tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
+	} else {
+		if (subcap_id == TPM_CAP_FLAG_PERM ||
+		    subcap_id == TPM_CAP_FLAG_VOL)
+			tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
+		else
+			tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
+		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
+		tpm_cmd.params.getcap_in.subcap = subcap_id;
+	}
+	rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
+	if (!rc)
+		*cap = tpm_cmd.params.getcap_out.cap;
+	return rc;
+}
+
+void tpm_gen_interrupt(struct tpm_chip *chip)
+{
+	struct	tpm_cmd_t tpm_cmd;
+	ssize_t rc;
+
+	tpm_cmd.header.in = tpm_getcap_header;
+	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
+	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
+	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
+
+	rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
+			"attempting to determine the timeouts");
+}
+EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
+
+#define TPM_ORD_STARTUP cpu_to_be32(153)
+#define TPM_ST_CLEAR cpu_to_be16(1)
+#define TPM_ST_STATE cpu_to_be16(2)
+#define TPM_ST_DEACTIVATED cpu_to_be16(3)
+static const struct tpm_input_header tpm_startup_header = {
+	.tag = TPM_TAG_RQU_COMMAND,
+	.length = cpu_to_be32(12),
+	.ordinal = TPM_ORD_STARTUP
+};
+
+static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
+{
+	struct tpm_cmd_t start_cmd;
+	start_cmd.header.in = tpm_startup_header;
+	start_cmd.params.startup_in.startup_type = startup_type;
+	return transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE,
+			    "attempting to start the TPM");
+}
+
+int tpm_get_timeouts(struct tpm_chip *chip)
+{
+	struct tpm_cmd_t tpm_cmd;
+	struct timeout_t *timeout_cap;
+	struct duration_t *duration_cap;
+	ssize_t rc;
+	u32 timeout;
+	unsigned int scale = 1;
+
+	tpm_cmd.header.in = tpm_getcap_header;
+	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
+	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
+	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
+	rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL);
+
+	if (rc == TPM_ERR_INVALID_POSTINIT) {
+		/* The TPM is not started, we are the first to talk to it.
+		   Execute a startup command. */
+		dev_info(chip->dev, "Issuing TPM_STARTUP");
+		if (tpm_startup(chip, TPM_ST_CLEAR))
+			return rc;
+
+		tpm_cmd.header.in = tpm_getcap_header;
+		tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
+		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
+		tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
+		rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
+				  NULL);
+	}
+	if (rc) {
+		dev_err(chip->dev,
+			"A TPM error (%zd) occurred attempting to determine the timeouts\n",
+			rc);
+		goto duration;
+	}
+
+	if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
+	    be32_to_cpu(tpm_cmd.header.out.length)
+	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
+		return -EINVAL;
+
+	timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
+	/* Don't overwrite default if value is 0 */
+	timeout = be32_to_cpu(timeout_cap->a);
+	if (timeout && timeout < 1000) {
+		/* timeouts in msec rather usec */
+		scale = 1000;
+		chip->vendor.timeout_adjusted = true;
+	}
+	if (timeout)
+		chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
+	timeout = be32_to_cpu(timeout_cap->b);
+	if (timeout)
+		chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
+	timeout = be32_to_cpu(timeout_cap->c);
+	if (timeout)
+		chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
+	timeout = be32_to_cpu(timeout_cap->d);
+	if (timeout)
+		chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
+
+duration:
+	tpm_cmd.header.in = tpm_getcap_header;
+	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
+	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
+	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
+
+	rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
+			"attempting to determine the durations");
+	if (rc)
+		return rc;
+
+	if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
+	    be32_to_cpu(tpm_cmd.header.out.length)
+	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
+		return -EINVAL;
+
+	duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
+	chip->vendor.duration[TPM_SHORT] =
+	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
+	chip->vendor.duration[TPM_MEDIUM] =
+	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
+	chip->vendor.duration[TPM_LONG] =
+	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
+
+	/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
+	 * value wrong and apparently reports msecs rather than usecs. So we
+	 * fix up the resulting too-small TPM_SHORT value to make things work.
+	 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
+	 */
+	if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
+		chip->vendor.duration[TPM_SHORT] = HZ;
+		chip->vendor.duration[TPM_MEDIUM] *= 1000;
+		chip->vendor.duration[TPM_LONG] *= 1000;
+		chip->vendor.duration_adjusted = true;
+		dev_info(chip->dev, "Adjusting TPM timeout parameters.");
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tpm_get_timeouts);
+
+#define TPM_ORD_CONTINUE_SELFTEST 83
+#define CONTINUE_SELFTEST_RESULT_SIZE 10
+
+static struct tpm_input_header continue_selftest_header = {
+	.tag = TPM_TAG_RQU_COMMAND,
+	.length = cpu_to_be32(10),
+	.ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
+};
+
+/**
+ * tpm_continue_selftest -- run TPM's selftest
+ * @chip: TPM chip to use
+ *
+ * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
+ * a TPM error code.
+ */
+static int tpm_continue_selftest(struct tpm_chip *chip)
+{
+	int rc;
+	struct tpm_cmd_t cmd;
+
+	cmd.header.in = continue_selftest_header;
+	rc = transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
+			  "continue selftest");
+	return rc;
+}
+
+ssize_t tpm_show_enabled(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	cap_t cap;
+	ssize_t rc;
+
+	rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
+			 "attempting to determine the permanent enabled state");
+	if (rc)
+		return 0;
+
+	rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_show_enabled);
+
+ssize_t tpm_show_active(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	cap_t cap;
+	ssize_t rc;
+
+	rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
+			 "attempting to determine the permanent active state");
+	if (rc)
+		return 0;
+
+	rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_show_active);
+
+ssize_t tpm_show_owned(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	cap_t cap;
+	ssize_t rc;
+
+	rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
+			 "attempting to determine the owner state");
+	if (rc)
+		return 0;
+
+	rc = sprintf(buf, "%d\n", cap.owned);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_show_owned);
+
+ssize_t tpm_show_temp_deactivated(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	cap_t cap;
+	ssize_t rc;
+
+	rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
+			 "attempting to determine the temporary state");
+	if (rc)
+		return 0;
+
+	rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
+
+/*
+ * tpm_chip_find_get - return tpm_chip for given chip number
+ */
+static struct tpm_chip *tpm_chip_find_get(int chip_num)
+{
+	struct tpm_chip *pos, *chip = NULL;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
+		if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
+			continue;
+
+		if (try_module_get(pos->dev->driver->owner)) {
+			chip = pos;
+			break;
+		}
+	}
+	rcu_read_unlock();
+	return chip;
+}
+
+#define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
+#define READ_PCR_RESULT_SIZE 30
+static struct tpm_input_header pcrread_header = {
+	.tag = TPM_TAG_RQU_COMMAND,
+	.length = cpu_to_be32(14),
+	.ordinal = TPM_ORDINAL_PCRREAD
+};
+
+static int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
+{
+	int rc;
+	struct tpm_cmd_t cmd;
+
+	cmd.header.in = pcrread_header;
+	cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
+	rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
+			  "attempting to read a pcr value");
+
+	if (rc == 0)
+		memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
+		       TPM_DIGEST_SIZE);
+	return rc;
+}
+
+/**
+ * tpm_pcr_read - read a pcr value
+ * @chip_num:	tpm idx # or ANY
+ * @pcr_idx:	pcr idx to retrieve
+ * @res_buf:	TPM_PCR value
+ *		size of res_buf is 20 bytes (or NULL if you don't care)
+ *
+ * The TPM driver should be built-in, but for whatever reason it
+ * isn't, protect against the chip disappearing, by incrementing
+ * the module usage count.
+ */
+int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
+{
+	struct tpm_chip *chip;
+	int rc;
+
+	chip = tpm_chip_find_get(chip_num);
+	if (chip == NULL)
+		return -ENODEV;
+	rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
+	tpm_chip_put(chip);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_pcr_read);
+
+/**
+ * tpm_pcr_extend - extend pcr value with hash
+ * @chip_num:	tpm idx # or AN&
+ * @pcr_idx:	pcr idx to extend
+ * @hash:	hash value used to extend pcr value
+ *
+ * The TPM driver should be built-in, but for whatever reason it
+ * isn't, protect against the chip disappearing, by incrementing
+ * the module usage count.
+ */
+#define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
+#define EXTEND_PCR_RESULT_SIZE 34
+static struct tpm_input_header pcrextend_header = {
+	.tag = TPM_TAG_RQU_COMMAND,
+	.length = cpu_to_be32(34),
+	.ordinal = TPM_ORD_PCR_EXTEND
+};
+
+int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
+{
+	struct tpm_cmd_t cmd;
+	int rc;
+	struct tpm_chip *chip;
+
+	chip = tpm_chip_find_get(chip_num);
+	if (chip == NULL)
+		return -ENODEV;
+
+	cmd.header.in = pcrextend_header;
+	cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
+	memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
+	rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
+			  "attempting extend a PCR value");
+
+	tpm_chip_put(chip);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_pcr_extend);
+
+/**
+ * tpm_do_selftest - have the TPM continue its selftest and wait until it
+ *                   can receive further commands
+ * @chip: TPM chip to use
+ *
+ * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
+ * a TPM error code.
+ */
+int tpm_do_selftest(struct tpm_chip *chip)
+{
+	int rc;
+	unsigned int loops;
+	unsigned int delay_msec = 100;
+	unsigned long duration;
+	struct tpm_cmd_t cmd;
+
+	duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
+
+	loops = jiffies_to_msecs(duration) / delay_msec;
+
+	rc = tpm_continue_selftest(chip);
+	/* This may fail if there was no TPM driver during a suspend/resume
+	 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
+	 */
+	if (rc)
+		return rc;
+
+	do {
+		/* Attempt to read a PCR value */
+		cmd.header.in = pcrread_header;
+		cmd.params.pcrread_in.pcr_idx = cpu_to_be32(0);
+		rc = tpm_transmit(chip, (u8 *) &cmd, READ_PCR_RESULT_SIZE);
+		/* Some buggy TPMs will not respond to tpm_tis_ready() for
+		 * around 300ms while the self test is ongoing, keep trying
+		 * until the self test duration expires. */
+		if (rc == -ETIME) {
+			dev_info(chip->dev, HW_ERR "TPM command timed out during continue self test");
+			msleep(delay_msec);
+			continue;
+		}
+
+		if (rc < TPM_HEADER_SIZE)
+			return -EFAULT;
+
+		rc = be32_to_cpu(cmd.header.out.return_code);
+		if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
+			dev_info(chip->dev,
+				 "TPM is disabled/deactivated (0x%X)\n", rc);
+			/* TPM is disabled and/or deactivated; driver can
+			 * proceed and TPM does handle commands for
+			 * suspend/resume correctly
+			 */
+			return 0;
+		}
+		if (rc != TPM_WARN_DOING_SELFTEST)
+			return rc;
+		msleep(delay_msec);
+	} while (--loops > 0);
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_do_selftest);
+
+int tpm_send(u32 chip_num, void *cmd, size_t buflen)
+{
+	struct tpm_chip *chip;
+	int rc;
+
+	chip = tpm_chip_find_get(chip_num);
+	if (chip == NULL)
+		return -ENODEV;
+
+	rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
+
+	tpm_chip_put(chip);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_send);
+
+ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
+		      char *buf)
+{
+	cap_t cap;
+	u8 digest[TPM_DIGEST_SIZE];
+	ssize_t rc;
+	int i, j, num_pcrs;
+	char *str = buf;
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+
+	rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
+			"attempting to determine the number of PCRS");
+	if (rc)
+		return 0;
+
+	num_pcrs = be32_to_cpu(cap.num_pcrs);
+	for (i = 0; i < num_pcrs; i++) {
+		rc = __tpm_pcr_read(chip, i, digest);
+		if (rc)
+			break;
+		str += sprintf(str, "PCR-%02d: ", i);
+		for (j = 0; j < TPM_DIGEST_SIZE; j++)
+			str += sprintf(str, "%02X ", digest[j]);
+		str += sprintf(str, "\n");
+	}
+	return str - buf;
+}
+EXPORT_SYMBOL_GPL(tpm_show_pcrs);
+
+#define  READ_PUBEK_RESULT_SIZE 314
+#define TPM_ORD_READPUBEK cpu_to_be32(124)
+static struct tpm_input_header tpm_readpubek_header = {
+	.tag = TPM_TAG_RQU_COMMAND,
+	.length = cpu_to_be32(30),
+	.ordinal = TPM_ORD_READPUBEK
+};
+
+ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
+		       char *buf)
+{
+	u8 *data;
+	struct tpm_cmd_t tpm_cmd;
+	ssize_t err;
+	int i, rc;
+	char *str = buf;
+
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+
+	tpm_cmd.header.in = tpm_readpubek_header;
+	err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
+			"attempting to read the PUBEK");
+	if (err)
+		goto out;
+
+	/*
+	   ignore header 10 bytes
+	   algorithm 32 bits (1 == RSA )
+	   encscheme 16 bits
+	   sigscheme 16 bits
+	   parameters (RSA 12->bytes: keybit, #primes, expbit)
+	   keylenbytes 32 bits
+	   256 byte modulus
+	   ignore checksum 20 bytes
+	 */
+	data = tpm_cmd.params.readpubek_out_buffer;
+	str +=
+	    sprintf(str,
+		    "Algorithm: %02X %02X %02X %02X\n"
+		    "Encscheme: %02X %02X\n"
+		    "Sigscheme: %02X %02X\n"
+		    "Parameters: %02X %02X %02X %02X "
+		    "%02X %02X %02X %02X "
+		    "%02X %02X %02X %02X\n"
+		    "Modulus length: %d\n"
+		    "Modulus:\n",
+		    data[0], data[1], data[2], data[3],
+		    data[4], data[5],
+		    data[6], data[7],
+		    data[12], data[13], data[14], data[15],
+		    data[16], data[17], data[18], data[19],
+		    data[20], data[21], data[22], data[23],
+		    be32_to_cpu(*((__be32 *) (data + 24))));
+
+	for (i = 0; i < 256; i++) {
+		str += sprintf(str, "%02X ", data[i + 28]);
+		if ((i + 1) % 16 == 0)
+			str += sprintf(str, "\n");
+	}
+out:
+	rc = str - buf;
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_show_pubek);
+
+
+ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
+		      char *buf)
+{
+	cap_t cap;
+	ssize_t rc;
+	char *str = buf;
+
+	rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
+			"attempting to determine the manufacturer");
+	if (rc)
+		return 0;
+	str += sprintf(str, "Manufacturer: 0x%x\n",
+		       be32_to_cpu(cap.manufacturer_id));
+
+	/* Try to get a TPM version 1.2 TPM_CAP_VERSION_INFO */
+	rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
+			 "attempting to determine the 1.2 version");
+	if (!rc) {
+		str += sprintf(str,
+			       "TCG version: %d.%d\nFirmware version: %d.%d\n",
+			       cap.tpm_version_1_2.Major,
+			       cap.tpm_version_1_2.Minor,
+			       cap.tpm_version_1_2.revMajor,
+			       cap.tpm_version_1_2.revMinor);
+	} else {
+		/* Otherwise just use TPM_STRUCT_VER */
+		rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
+				"attempting to determine the 1.1 version");
+		if (rc)
+			return 0;
+		str += sprintf(str,
+			       "TCG version: %d.%d\nFirmware version: %d.%d\n",
+			       cap.tpm_version.Major,
+			       cap.tpm_version.Minor,
+			       cap.tpm_version.revMajor,
+			       cap.tpm_version.revMinor);
+	}
+
+	return str - buf;
+}
+EXPORT_SYMBOL_GPL(tpm_show_caps);
+
+ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
+			  char *buf)
+{
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+
+	if (chip->vendor.duration[TPM_LONG] == 0)
+		return 0;
+
+	return sprintf(buf, "%d %d %d [%s]\n",
+		       jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
+		       jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
+		       jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
+		       chip->vendor.duration_adjusted
+		       ? "adjusted" : "original");
+}
+EXPORT_SYMBOL_GPL(tpm_show_durations);
+
+ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
+			  char *buf)
+{
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%d %d %d %d [%s]\n",
+		       jiffies_to_usecs(chip->vendor.timeout_a),
+		       jiffies_to_usecs(chip->vendor.timeout_b),
+		       jiffies_to_usecs(chip->vendor.timeout_c),
+		       jiffies_to_usecs(chip->vendor.timeout_d),
+		       chip->vendor.timeout_adjusted
+		       ? "adjusted" : "original");
+}
+EXPORT_SYMBOL_GPL(tpm_show_timeouts);
+
+ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+	if (chip == NULL)
+		return 0;
+
+	chip->vendor.cancel(chip);
+	return count;
+}
+EXPORT_SYMBOL_GPL(tpm_store_cancel);
+
+static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
+					bool check_cancel, bool *canceled)
+{
+	u8 status = chip->vendor.status(chip);
+
+	*canceled = false;
+	if ((status & mask) == mask)
+		return true;
+	if (check_cancel && chip->vendor.req_canceled(chip, status)) {
+		*canceled = true;
+		return true;
+	}
+	return false;
+}
+
+int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
+		      wait_queue_head_t *queue, bool check_cancel)
+{
+	unsigned long stop;
+	long rc;
+	u8 status;
+	bool canceled = false;
+
+	/* check current status */
+	status = chip->vendor.status(chip);
+	if ((status & mask) == mask)
+		return 0;
+
+	stop = jiffies + timeout;
+
+	if (chip->vendor.irq) {
+again:
+		timeout = stop - jiffies;
+		if ((long)timeout <= 0)
+			return -ETIME;
+		rc = wait_event_interruptible_timeout(*queue,
+			wait_for_tpm_stat_cond(chip, mask, check_cancel,
+					       &canceled),
+			timeout);
+		if (rc > 0) {
+			if (canceled)
+				return -ECANCELED;
+			return 0;
+		}
+		if (rc == -ERESTARTSYS && freezing(current)) {
+			clear_thread_flag(TIF_SIGPENDING);
+			goto again;
+		}
+	} else {
+		do {
+			msleep(TPM_TIMEOUT);
+			status = chip->vendor.status(chip);
+			if ((status & mask) == mask)
+				return 0;
+		} while (time_before(jiffies, stop));
+	}
+	return -ETIME;
+}
+EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
+/*
+ * Device file system interface to the TPM
+ *
+ * It's assured that the chip will be opened just once,
+ * by the check of is_open variable, which is protected
+ * by driver_lock.
+ */
+int tpm_open(struct inode *inode, struct file *file)
+{
+	struct miscdevice *misc = file->private_data;
+	struct tpm_chip *chip = container_of(misc, struct tpm_chip,
+					     vendor.miscdev);
+
+	if (test_and_set_bit(0, &chip->is_open)) {
+		dev_dbg(chip->dev, "Another process owns this TPM\n");
+		return -EBUSY;
+	}
+
+	chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+	if (chip->data_buffer == NULL) {
+		clear_bit(0, &chip->is_open);
+		return -ENOMEM;
+	}
+
+	atomic_set(&chip->data_pending, 0);
+
+	file->private_data = chip;
+	get_device(chip->dev);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tpm_open);
+
+/*
+ * Called on file close
+ */
+int tpm_release(struct inode *inode, struct file *file)
+{
+	struct tpm_chip *chip = file->private_data;
+
+	del_singleshot_timer_sync(&chip->user_read_timer);
+	flush_work(&chip->work);
+	file->private_data = NULL;
+	atomic_set(&chip->data_pending, 0);
+	kzfree(chip->data_buffer);
+	clear_bit(0, &chip->is_open);
+	put_device(chip->dev);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tpm_release);
+
+ssize_t tpm_write(struct file *file, const char __user *buf,
+		  size_t size, loff_t *off)
+{
+	struct tpm_chip *chip = file->private_data;
+	size_t in_size = size;
+	ssize_t out_size;
+
+	/* cannot perform a write until the read has cleared
+	   either via tpm_read or a user_read_timer timeout.
+	   This also prevents splitted buffered writes from blocking here.
+	*/
+	if (atomic_read(&chip->data_pending) != 0)
+		return -EBUSY;
+
+	if (in_size > TPM_BUFSIZE)
+		return -E2BIG;
+
+	mutex_lock(&chip->buffer_mutex);
+
+	if (copy_from_user
+	    (chip->data_buffer, (void __user *) buf, in_size)) {
+		mutex_unlock(&chip->buffer_mutex);
+		return -EFAULT;
+	}
+
+	/* atomic tpm command send and result receive */
+	out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
+	if (out_size < 0) {
+		mutex_unlock(&chip->buffer_mutex);
+		return out_size;
+	}
+
+	atomic_set(&chip->data_pending, out_size);
+	mutex_unlock(&chip->buffer_mutex);
+
+	/* Set a timeout by which the reader must come claim the result */
+	mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
+
+	return in_size;
+}
+EXPORT_SYMBOL_GPL(tpm_write);
+
+ssize_t tpm_read(struct file *file, char __user *buf,
+		 size_t size, loff_t *off)
+{
+	struct tpm_chip *chip = file->private_data;
+	ssize_t ret_size;
+	int rc;
+
+	del_singleshot_timer_sync(&chip->user_read_timer);
+	flush_work(&chip->work);
+	ret_size = atomic_read(&chip->data_pending);
+	if (ret_size > 0) {	/* relay data */
+		ssize_t orig_ret_size = ret_size;
+		if (size < ret_size)
+			ret_size = size;
+
+		mutex_lock(&chip->buffer_mutex);
+		rc = copy_to_user(buf, chip->data_buffer, ret_size);
+		memset(chip->data_buffer, 0, orig_ret_size);
+		if (rc)
+			ret_size = -EFAULT;
+
+		mutex_unlock(&chip->buffer_mutex);
+	}
+
+	atomic_set(&chip->data_pending, 0);
+
+	return ret_size;
+}
+EXPORT_SYMBOL_GPL(tpm_read);
+
+void tpm_remove_hardware(struct device *dev)
+{
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+
+	if (chip == NULL) {
+		dev_err(dev, "No device data found\n");
+		return;
+	}
+
+	spin_lock(&driver_lock);
+	list_del_rcu(&chip->list);
+	spin_unlock(&driver_lock);
+	synchronize_rcu();
+
+	misc_deregister(&chip->vendor.miscdev);
+	sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
+	tpm_remove_ppi(&dev->kobj);
+	tpm_bios_log_teardown(chip->bios_dir);
+
+	/* write it this way to be explicit (chip->dev == dev) */
+	put_device(chip->dev);
+}
+EXPORT_SYMBOL_GPL(tpm_remove_hardware);
+
+#define TPM_ORD_SAVESTATE cpu_to_be32(152)
+#define SAVESTATE_RESULT_SIZE 10
+
+static struct tpm_input_header savestate_header = {
+	.tag = TPM_TAG_RQU_COMMAND,
+	.length = cpu_to_be32(10),
+	.ordinal = TPM_ORD_SAVESTATE
+};
+
+/*
+ * We are about to suspend. Save the TPM state
+ * so that it can be restored.
+ */
+int tpm_pm_suspend(struct device *dev)
+{
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+	struct tpm_cmd_t cmd;
+	int rc, try;
+
+	u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
+
+	if (chip == NULL)
+		return -ENODEV;
+
+	/* for buggy tpm, flush pcrs with extend to selected dummy */
+	if (tpm_suspend_pcr) {
+		cmd.header.in = pcrextend_header;
+		cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
+		memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
+		       TPM_DIGEST_SIZE);
+		rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
+				  "extending dummy pcr before suspend");
+	}
+
+	/* now do the actual savestate */
+	for (try = 0; try < TPM_RETRY; try++) {
+		cmd.header.in = savestate_header;
+		rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, NULL);
+
+		/*
+		 * If the TPM indicates that it is too busy to respond to
+		 * this command then retry before giving up.  It can take
+		 * several seconds for this TPM to be ready.
+		 *
+		 * This can happen if the TPM has already been sent the
+		 * SaveState command before the driver has loaded.  TCG 1.2
+		 * specification states that any communication after SaveState
+		 * may cause the TPM to invalidate previously saved state.
+		 */
+		if (rc != TPM_WARN_RETRY)
+			break;
+		msleep(TPM_TIMEOUT_RETRY);
+	}
+
+	if (rc)
+		dev_err(chip->dev,
+			"Error (%d) sending savestate before suspend\n", rc);
+	else if (try > 0)
+		dev_warn(chip->dev, "TPM savestate took %dms\n",
+			 try * TPM_TIMEOUT_RETRY);
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_pm_suspend);
+
+/*
+ * Resume from a power safe. The BIOS already restored
+ * the TPM state.
+ */
+int tpm_pm_resume(struct device *dev)
+{
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+
+	if (chip == NULL)
+		return -ENODEV;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tpm_pm_resume);
+
+#define TPM_GETRANDOM_RESULT_SIZE	18
+static struct tpm_input_header tpm_getrandom_header = {
+	.tag = TPM_TAG_RQU_COMMAND,
+	.length = cpu_to_be32(14),
+	.ordinal = TPM_ORD_GET_RANDOM
+};
+
+/**
+ * tpm_get_random() - Get random bytes from the tpm's RNG
+ * @chip_num: A specific chip number for the request or TPM_ANY_NUM
+ * @out: destination buffer for the random bytes
+ * @max: the max number of bytes to write to @out
+ *
+ * Returns < 0 on error and the number of bytes read on success
+ */
+int tpm_get_random(u32 chip_num, u8 *out, size_t max)
+{
+	struct tpm_chip *chip;
+	struct tpm_cmd_t tpm_cmd;
+	u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
+	int err, total = 0, retries = 5;
+	u8 *dest = out;
+
+	chip = tpm_chip_find_get(chip_num);
+	if (chip == NULL)
+		return -ENODEV;
+
+	if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
+		return -EINVAL;
+
+	do {
+		tpm_cmd.header.in = tpm_getrandom_header;
+		tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
+
+		err = transmit_cmd(chip, &tpm_cmd,
+				   TPM_GETRANDOM_RESULT_SIZE + num_bytes,
+				   "attempting get random");
+		if (err)
+			break;
+
+		recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
+		memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
+
+		dest += recd;
+		total += recd;
+		num_bytes -= recd;
+	} while (retries-- && total < max);
+
+	return total ? total : -EIO;
+}
+EXPORT_SYMBOL_GPL(tpm_get_random);
+
+/* In case vendor provided release function, call it too.*/
+
+void tpm_dev_vendor_release(struct tpm_chip *chip)
+{
+	if (!chip)
+		return;
+
+	if (chip->vendor.release)
+		chip->vendor.release(chip->dev);
+
+	clear_bit(chip->dev_num, dev_mask);
+}
+EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
+
+
+/*
+ * Once all references to platform device are down to 0,
+ * release all allocated structures.
+ */
+void tpm_dev_release(struct device *dev)
+{
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+
+	if (!chip)
+		return;
+
+	tpm_dev_vendor_release(chip);
+
+	chip->release(dev);
+	kfree(chip);
+}
+EXPORT_SYMBOL_GPL(tpm_dev_release);
+
+/*
+ * Called from tpm_<specific>.c probe function only for devices
+ * the driver has determined it should claim.  Prior to calling
+ * this function the specific probe function has called pci_enable_device
+ * upon errant exit from this function specific probe function should call
+ * pci_disable_device
+ */
+struct tpm_chip *tpm_register_hardware(struct device *dev,
+					const struct tpm_vendor_specific *entry)
+{
+	struct tpm_chip *chip;
+
+	/* Driver specific per-device data */
+	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+
+	if (chip == NULL)
+		return NULL;
+
+	mutex_init(&chip->buffer_mutex);
+	mutex_init(&chip->tpm_mutex);
+	INIT_LIST_HEAD(&chip->list);
+
+	INIT_WORK(&chip->work, timeout_work);
+
+	setup_timer(&chip->user_read_timer, user_reader_timeout,
+			(unsigned long)chip);
+
+	memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
+
+	chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
+
+	if (chip->dev_num >= TPM_NUM_DEVICES) {
+		dev_err(dev, "No available tpm device numbers\n");
+		goto out_free;
+	} else if (chip->dev_num == 0)
+		chip->vendor.miscdev.minor = TPM_MINOR;
+	else
+		chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
+
+	set_bit(chip->dev_num, dev_mask);
+
+	scnprintf(chip->devname, sizeof(chip->devname), "%s%d", "tpm",
+		  chip->dev_num);
+	chip->vendor.miscdev.name = chip->devname;
+
+	chip->vendor.miscdev.parent = dev;
+	chip->dev = get_device(dev);
+	chip->release = dev->release;
+	dev->release = tpm_dev_release;
+	dev_set_drvdata(dev, chip);
+
+	if (misc_register(&chip->vendor.miscdev)) {
+		dev_err(chip->dev,
+			"unable to misc_register %s, minor %d\n",
+			chip->vendor.miscdev.name,
+			chip->vendor.miscdev.minor);
+		goto put_device;
+	}
+
+	if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
+		misc_deregister(&chip->vendor.miscdev);
+		goto put_device;
+	}
+
+	if (tpm_add_ppi(&dev->kobj)) {
+		misc_deregister(&chip->vendor.miscdev);
+		goto put_device;
+	}
+
+	chip->bios_dir = tpm_bios_log_setup(chip->devname);
+
+	/* Make chip available */
+	spin_lock(&driver_lock);
+	list_add_rcu(&chip->list, &tpm_chip_list);
+	spin_unlock(&driver_lock);
+
+	return chip;
+
+put_device:
+	put_device(chip->dev);
+out_free:
+	kfree(chip);
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(tpm_register_hardware);
+
+MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
+MODULE_DESCRIPTION("TPM Driver");
+MODULE_VERSION("2.0");
+MODULE_LICENSE("GPL");