Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1451 insertions, 0 deletions

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
new file mode 100644
index 000000000..43c3f9b87
--- /dev/null
+++ b/drivers/char/tpm/tpm-interface.c
@@ -0,0 +1,1451 @@
+/*
+ * Copyright (C) 2004 IBM Corporation
+ * Copyright (C) 2014 Intel 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 <linux/tpm_eventlog.h>
+
+#include "tpm.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 facilitate flush on suspend.");
+
+/*
+ * 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,
+};
+
+/*
+ * 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;
+
+	/*
+	 * We only have a duration table for protected commands, where the upper
+	 * 16 bits are 0. For the few other ordinals the fallback will be used.
+	 */
+	if (ordinal < TPM_MAX_ORDINAL)
+		duration_idx = tpm_ordinal_duration[ordinal];
+
+	if (duration_idx != TPM_UNDEFINED)
+		duration = chip->duration[duration_idx];
+	if (duration <= 0)
+		return 2 * 60 * HZ;
+	else
+		return duration;
+}
+EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
+
+static int tpm_validate_command(struct tpm_chip *chip,
+				 struct tpm_space *space,
+				 const u8 *cmd,
+				 size_t len)
+{
+	const struct tpm_input_header *header = (const void *)cmd;
+	int i;
+	u32 cc;
+	u32 attrs;
+	unsigned int nr_handles;
+
+	if (len < TPM_HEADER_SIZE)
+		return -EINVAL;
+
+	if (!space)
+		return 0;
+
+	if (chip->flags & TPM_CHIP_FLAG_TPM2 && chip->nr_commands) {
+		cc = be32_to_cpu(header->ordinal);
+
+		i = tpm2_find_cc(chip, cc);
+		if (i < 0) {
+			dev_dbg(&chip->dev, "0x%04X is an invalid command\n",
+				cc);
+			return -EOPNOTSUPP;
+		}
+
+		attrs = chip->cc_attrs_tbl[i];
+		nr_handles =
+			4 * ((attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0));
+		if (len < TPM_HEADER_SIZE + 4 * nr_handles)
+			goto err_len;
+	}
+
+	return 0;
+err_len:
+	dev_dbg(&chip->dev,
+		"%s: insufficient command length %zu", __func__, len);
+	return -EINVAL;
+}
+
+static int tpm_request_locality(struct tpm_chip *chip, unsigned int flags)
+{
+	int rc;
+
+	if (flags & TPM_TRANSMIT_NESTED)
+		return 0;
+
+	if (!chip->ops->request_locality)
+		return 0;
+
+	rc = chip->ops->request_locality(chip, 0);
+	if (rc < 0)
+		return rc;
+
+	chip->locality = rc;
+
+	return 0;
+}
+
+static void tpm_relinquish_locality(struct tpm_chip *chip, unsigned int flags)
+{
+	int rc;
+
+	if (flags & TPM_TRANSMIT_NESTED)
+		return;
+
+	if (!chip->ops->relinquish_locality)
+		return;
+
+	rc = chip->ops->relinquish_locality(chip, chip->locality);
+	if (rc)
+		dev_err(&chip->dev, "%s: : error %d\n", __func__, rc);
+
+	chip->locality = -1;
+}
+
+static int tpm_cmd_ready(struct tpm_chip *chip, unsigned int flags)
+{
+	if (flags & TPM_TRANSMIT_NESTED)
+		return 0;
+
+	if (!chip->ops->cmd_ready)
+		return 0;
+
+	return chip->ops->cmd_ready(chip);
+}
+
+static int tpm_go_idle(struct tpm_chip *chip, unsigned int flags)
+{
+	if (flags & TPM_TRANSMIT_NESTED)
+		return 0;
+
+	if (!chip->ops->go_idle)
+		return 0;
+
+	return chip->ops->go_idle(chip);
+}
+
+static ssize_t tpm_try_transmit(struct tpm_chip *chip,
+				struct tpm_space *space,
+				u8 *buf, size_t bufsiz,
+				unsigned int flags)
+{
+	struct tpm_output_header *header = (void *)buf;
+	int rc;
+	ssize_t len = 0;
+	u32 count, ordinal;
+	unsigned long stop;
+	bool need_locality;
+
+	rc = tpm_validate_command(chip, space, buf, bufsiz);
+	if (rc == -EINVAL)
+		return rc;
+	/*
+	 * If the command is not implemented by the TPM, synthesize a
+	 * response with a TPM2_RC_COMMAND_CODE return for user-space.
+	 */
+	if (rc == -EOPNOTSUPP) {
+		header->length = cpu_to_be32(sizeof(*header));
+		header->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
+		header->return_code = cpu_to_be32(TPM2_RC_COMMAND_CODE |
+						  TSS2_RESMGR_TPM_RC_LAYER);
+		return sizeof(*header);
+	}
+
+	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;
+	}
+
+	if (!(flags & TPM_TRANSMIT_UNLOCKED) && !(flags & TPM_TRANSMIT_NESTED))
+		mutex_lock(&chip->tpm_mutex);
+
+	if (chip->ops->clk_enable != NULL)
+		chip->ops->clk_enable(chip, true);
+
+	/* Store the decision as chip->locality will be changed. */
+	need_locality = chip->locality == -1;
+
+	if (need_locality) {
+		rc = tpm_request_locality(chip, flags);
+		if (rc < 0) {
+			need_locality = false;
+			goto out_locality;
+		}
+	}
+
+	rc = tpm_cmd_ready(chip, flags);
+	if (rc)
+		goto out_locality;
+
+	rc = tpm2_prepare_space(chip, space, ordinal, buf);
+	if (rc)
+		goto out;
+
+	rc = chip->ops->send(chip, buf, count);
+	if (rc < 0) {
+		if (rc != -EPIPE)
+			dev_err(&chip->dev,
+				"%s: send(): error %d\n", __func__, rc);
+		goto out;
+	}
+
+	/* A sanity check. send() should just return zero on success e.g.
+	 * not the command length.
+	 */
+	if (rc > 0) {
+		dev_warn(&chip->dev,
+			 "%s: send(): invalid value %d\n", __func__, rc);
+		rc = 0;
+	}
+
+	if (chip->flags & TPM_CHIP_FLAG_IRQ)
+		goto out_recv;
+
+	if (chip->flags & TPM_CHIP_FLAG_TPM2)
+		stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal);
+	else
+		stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
+	do {
+		u8 status = chip->ops->status(chip);
+		if ((status & chip->ops->req_complete_mask) ==
+		    chip->ops->req_complete_val)
+			goto out_recv;
+
+		if (chip->ops->req_canceled(chip, status)) {
+			dev_err(&chip->dev, "Operation Canceled\n");
+			rc = -ECANCELED;
+			goto out;
+		}
+
+		tpm_msleep(TPM_TIMEOUT_POLL);
+		rmb();
+	} while (time_before(jiffies, stop));
+
+	chip->ops->cancel(chip);
+	dev_err(&chip->dev, "Operation Timed out\n");
+	rc = -ETIME;
+	goto out;
+
+out_recv:
+	len = chip->ops->recv(chip, buf, bufsiz);
+	if (len < 0) {
+		rc = len;
+		dev_err(&chip->dev,
+			"tpm_transmit: tpm_recv: error %d\n", rc);
+		goto out;
+	} else if (len < TPM_HEADER_SIZE) {
+		rc = -EFAULT;
+		goto out;
+	}
+
+	if (len != be32_to_cpu(header->length)) {
+		rc = -EFAULT;
+		goto out;
+	}
+
+	rc = tpm2_commit_space(chip, space, ordinal, buf, &len);
+	if (rc)
+		dev_err(&chip->dev, "tpm2_commit_space: error %d\n", rc);
+
+out:
+	/* may fail but do not override previous error value in rc */
+	tpm_go_idle(chip, flags);
+
+out_locality:
+	if (need_locality)
+		tpm_relinquish_locality(chip, flags);
+
+	if (chip->ops->clk_enable != NULL)
+		chip->ops->clk_enable(chip, false);
+
+	if (!(flags & TPM_TRANSMIT_UNLOCKED) && !(flags & TPM_TRANSMIT_NESTED))
+		mutex_unlock(&chip->tpm_mutex);
+	return rc ? rc : len;
+}
+
+/**
+ * tpm_transmit - Internal kernel interface to transmit TPM commands.
+ *
+ * @chip: TPM chip to use
+ * @space: tpm space
+ * @buf: TPM command buffer
+ * @bufsiz: length of the TPM command buffer
+ * @flags: tpm transmit flags - bitmap
+ *
+ * A wrapper around tpm_try_transmit that handles TPM2_RC_RETRY
+ * returns from the TPM and retransmits the command after a delay up
+ * to a maximum wait of TPM2_DURATION_LONG.
+ *
+ * Note: TPM1 never returns TPM2_RC_RETRY so the retry logic is TPM2
+ * only
+ *
+ * Return:
+ *     the length of the return when the operation is successful.
+ *     A negative number for system errors (errno).
+ */
+ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
+		     u8 *buf, size_t bufsiz, unsigned int flags)
+{
+	struct tpm_output_header *header = (struct tpm_output_header *)buf;
+	/* space for header and handles */
+	u8 save[TPM_HEADER_SIZE + 3*sizeof(u32)];
+	unsigned int delay_msec = TPM2_DURATION_SHORT;
+	u32 rc = 0;
+	ssize_t ret;
+	const size_t save_size = min(space ? sizeof(save) : TPM_HEADER_SIZE,
+				     bufsiz);
+	/* the command code is where the return code will be */
+	u32 cc = be32_to_cpu(header->return_code);
+
+	/*
+	 * Subtlety here: if we have a space, the handles will be
+	 * transformed, so when we restore the header we also have to
+	 * restore the handles.
+	 */
+	memcpy(save, buf, save_size);
+
+	for (;;) {
+		ret = tpm_try_transmit(chip, space, buf, bufsiz, flags);
+		if (ret < 0)
+			break;
+		rc = be32_to_cpu(header->return_code);
+		if (rc != TPM2_RC_RETRY && rc != TPM2_RC_TESTING)
+			break;
+		/*
+		 * return immediately if self test returns test
+		 * still running to shorten boot time.
+		 */
+		if (rc == TPM2_RC_TESTING && cc == TPM2_CC_SELF_TEST)
+			break;
+
+		if (delay_msec > TPM2_DURATION_LONG) {
+			if (rc == TPM2_RC_RETRY)
+				dev_err(&chip->dev, "in retry loop\n");
+			else
+				dev_err(&chip->dev,
+					"self test is still running\n");
+			break;
+		}
+		tpm_msleep(delay_msec);
+		delay_msec *= 2;
+		memcpy(buf, save, save_size);
+	}
+	return ret;
+}
+/**
+ * tpm_transmit_cmd - send a tpm command to the device
+ *    The function extracts tpm out header return code
+ *
+ * @chip: TPM chip to use
+ * @space: tpm space
+ * @buf: TPM command buffer
+ * @bufsiz: length of the buffer
+ * @min_rsp_body_length: minimum expected length of response body
+ * @flags: tpm transmit flags - bitmap
+ * @desc: command description used in the error message
+ *
+ * Return:
+ *     0 when the operation is successful.
+ *     A negative number for system errors (errno).
+ *     A positive number for a TPM error.
+ */
+ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space,
+			 void *buf, size_t bufsiz,
+			 size_t min_rsp_body_length, unsigned int flags,
+			 const char *desc)
+{
+	const struct tpm_output_header *header = buf;
+	int err;
+	ssize_t len;
+
+	len = tpm_transmit(chip, space, buf, bufsiz, flags);
+	if (len <  0)
+		return len;
+
+	err = be32_to_cpu(header->return_code);
+	if (err != 0 && err != TPM_ERR_DISABLED && err != TPM_ERR_DEACTIVATED
+	    && desc)
+		dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err,
+			desc);
+	if (err)
+		return err;
+
+	if (len < min_rsp_body_length + TPM_HEADER_SIZE)
+		return -EFAULT;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tpm_transmit_cmd);
+
+#define TPM_ORD_STARTUP 153
+#define TPM_ST_CLEAR 1
+
+/**
+ * tpm_startup - turn on the TPM
+ * @chip: TPM chip to use
+ *
+ * Normally the firmware should start the TPM. This function is provided as a
+ * workaround if this does not happen. A legal case for this could be for
+ * example when a TPM emulator is used.
+ *
+ * Return: same as tpm_transmit_cmd()
+ */
+int tpm_startup(struct tpm_chip *chip)
+{
+	struct tpm_buf buf;
+	int rc;
+
+	dev_info(&chip->dev, "starting up the TPM manually\n");
+
+	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+		rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_STARTUP);
+		if (rc < 0)
+			return rc;
+
+		tpm_buf_append_u16(&buf, TPM2_SU_CLEAR);
+	} else {
+		rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_STARTUP);
+		if (rc < 0)
+			return rc;
+
+		tpm_buf_append_u16(&buf, TPM_ST_CLEAR);
+	}
+
+	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
+			      "attempting to start the TPM");
+
+	tpm_buf_destroy(&buf);
+	return rc;
+}
+
+#define TPM_DIGEST_SIZE 20
+#define TPM_RET_CODE_IDX 6
+#define TPM_INTERNAL_RESULT_SIZE 200
+#define TPM_ORD_GET_CAP 101
+#define TPM_ORD_GET_RANDOM 70
+
+static const struct tpm_input_header tpm_getcap_header = {
+	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
+	.length = cpu_to_be32(22),
+	.ordinal = cpu_to_be32(TPM_ORD_GET_CAP)
+};
+
+ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
+		   const char *desc, size_t min_cap_length)
+{
+	struct tpm_buf buf;
+	int rc;
+
+	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_CAP);
+	if (rc)
+		return rc;
+
+	if (subcap_id == TPM_CAP_VERSION_1_1 ||
+	    subcap_id == TPM_CAP_VERSION_1_2) {
+		tpm_buf_append_u32(&buf, subcap_id);
+		tpm_buf_append_u32(&buf, 0);
+	} else {
+		if (subcap_id == TPM_CAP_FLAG_PERM ||
+		    subcap_id == TPM_CAP_FLAG_VOL)
+			tpm_buf_append_u32(&buf, TPM_CAP_FLAG);
+		else
+			tpm_buf_append_u32(&buf, TPM_CAP_PROP);
+
+		tpm_buf_append_u32(&buf, 4);
+		tpm_buf_append_u32(&buf, subcap_id);
+	}
+	rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE,
+			      min_cap_length, 0, desc);
+	if (!rc)
+		*cap = *(cap_t *)&buf.data[TPM_HEADER_SIZE + 4];
+
+	tpm_buf_destroy(&buf);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_getcap);
+
+int tpm_get_timeouts(struct tpm_chip *chip)
+{
+	cap_t cap;
+	unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4];
+	ssize_t rc;
+
+	if (chip->flags & TPM_CHIP_FLAG_HAVE_TIMEOUTS)
+		return 0;
+
+	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+		/* Fixed timeouts for TPM2 */
+		chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
+		chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
+		chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
+		chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
+		chip->duration[TPM_SHORT] =
+		    msecs_to_jiffies(TPM2_DURATION_SHORT);
+		chip->duration[TPM_MEDIUM] =
+		    msecs_to_jiffies(TPM2_DURATION_MEDIUM);
+		chip->duration[TPM_LONG] =
+		    msecs_to_jiffies(TPM2_DURATION_LONG);
+		chip->duration[TPM_LONG_LONG] =
+		    msecs_to_jiffies(TPM2_DURATION_LONG_LONG);
+
+		chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
+		return 0;
+	}
+
+	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL,
+			sizeof(cap.timeout));
+	if (rc == TPM_ERR_INVALID_POSTINIT) {
+		if (tpm_startup(chip))
+			return rc;
+
+		rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
+				"attempting to determine the timeouts",
+				sizeof(cap.timeout));
+	}
+
+	if (rc) {
+		dev_err(&chip->dev,
+			"A TPM error (%zd) occurred attempting to determine the timeouts\n",
+			rc);
+		return rc;
+	}
+
+	timeout_old[0] = jiffies_to_usecs(chip->timeout_a);
+	timeout_old[1] = jiffies_to_usecs(chip->timeout_b);
+	timeout_old[2] = jiffies_to_usecs(chip->timeout_c);
+	timeout_old[3] = jiffies_to_usecs(chip->timeout_d);
+	timeout_chip[0] = be32_to_cpu(cap.timeout.a);
+	timeout_chip[1] = be32_to_cpu(cap.timeout.b);
+	timeout_chip[2] = be32_to_cpu(cap.timeout.c);
+	timeout_chip[3] = be32_to_cpu(cap.timeout.d);
+	memcpy(timeout_eff, timeout_chip, sizeof(timeout_eff));
+
+	/*
+	 * Provide ability for vendor overrides of timeout values in case
+	 * of misreporting.
+	 */
+	if (chip->ops->update_timeouts != NULL)
+		chip->timeout_adjusted =
+			chip->ops->update_timeouts(chip, timeout_eff);
+
+	if (!chip->timeout_adjusted) {
+		/* Restore default if chip reported 0 */
+		int i;
+
+		for (i = 0; i < ARRAY_SIZE(timeout_eff); i++) {
+			if (timeout_eff[i])
+				continue;
+
+			timeout_eff[i] = timeout_old[i];
+			chip->timeout_adjusted = true;
+		}
+
+		if (timeout_eff[0] != 0 && timeout_eff[0] < 1000) {
+			/* timeouts in msec rather usec */
+			for (i = 0; i != ARRAY_SIZE(timeout_eff); i++)
+				timeout_eff[i] *= 1000;
+			chip->timeout_adjusted = true;
+		}
+	}
+
+	/* Report adjusted timeouts */
+	if (chip->timeout_adjusted) {
+		dev_info(&chip->dev,
+			 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
+			 timeout_chip[0], timeout_eff[0],
+			 timeout_chip[1], timeout_eff[1],
+			 timeout_chip[2], timeout_eff[2],
+			 timeout_chip[3], timeout_eff[3]);
+	}
+
+	chip->timeout_a = usecs_to_jiffies(timeout_eff[0]);
+	chip->timeout_b = usecs_to_jiffies(timeout_eff[1]);
+	chip->timeout_c = usecs_to_jiffies(timeout_eff[2]);
+	chip->timeout_d = usecs_to_jiffies(timeout_eff[3]);
+
+	rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
+			"attempting to determine the durations",
+			sizeof(cap.duration));
+	if (rc)
+		return rc;
+
+	chip->duration[TPM_SHORT] =
+		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
+	chip->duration[TPM_MEDIUM] =
+		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
+	chip->duration[TPM_LONG] =
+		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
+	chip->duration[TPM_LONG_LONG] = 0; /* not used under 1.2 */
+
+	/* 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->duration[TPM_SHORT] < (HZ / 100)) {
+		chip->duration[TPM_SHORT] = HZ;
+		chip->duration[TPM_MEDIUM] *= 1000;
+		chip->duration[TPM_LONG] *= 1000;
+		chip->duration_adjusted = true;
+		dev_info(&chip->dev, "Adjusting TPM timeout parameters.");
+	}
+
+	chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tpm_get_timeouts);
+
+#define TPM_ORD_CONTINUE_SELFTEST 83
+#define CONTINUE_SELFTEST_RESULT_SIZE 10
+
+static const struct tpm_input_header continue_selftest_header = {
+	.tag = cpu_to_be16(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 = tpm_transmit_cmd(chip, NULL, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
+			      0, 0, "continue selftest");
+	return rc;
+}
+
+#define TPM_ORDINAL_PCRREAD 21
+#define READ_PCR_RESULT_SIZE 30
+#define READ_PCR_RESULT_BODY_SIZE 20
+static const struct tpm_input_header pcrread_header = {
+	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
+	.length = cpu_to_be32(14),
+	.ordinal = cpu_to_be32(TPM_ORDINAL_PCRREAD)
+};
+
+int tpm_pcr_read_dev(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 = tpm_transmit_cmd(chip, NULL, &cmd, READ_PCR_RESULT_SIZE,
+			      READ_PCR_RESULT_BODY_SIZE, 0,
+			      "attempting to read a pcr value");
+
+	if (rc == 0)
+		memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
+		       TPM_DIGEST_SIZE);
+	return rc;
+}
+
+/**
+ * tpm_is_tpm2 - do we a have a TPM2 chip?
+ * @chip:	a &struct tpm_chip instance, %NULL for the default chip
+ *
+ * Return:
+ * 1 if we have a TPM2 chip.
+ * 0 if we don't have a TPM2 chip.
+ * A negative number for system errors (errno).
+ */
+int tpm_is_tpm2(struct tpm_chip *chip)
+{
+	int rc;
+
+	chip = tpm_find_get_ops(chip);
+	if (!chip)
+		return -ENODEV;
+
+	rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0;
+
+	tpm_put_ops(chip);
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_is_tpm2);
+
+/**
+ * tpm_pcr_read - read a PCR value from SHA1 bank
+ * @chip:	a &struct tpm_chip instance, %NULL for the default chip
+ * @pcr_idx:	the PCR to be retrieved
+ * @res_buf:	the value of the PCR
+ *
+ * Return: same as with tpm_transmit_cmd()
+ */
+int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
+{
+	int rc;
+
+	chip = tpm_find_get_ops(chip);
+	if (!chip)
+		return -ENODEV;
+	if (chip->flags & TPM_CHIP_FLAG_TPM2)
+		rc = tpm2_pcr_read(chip, pcr_idx, res_buf);
+	else
+		rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf);
+	tpm_put_ops(chip);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_pcr_read);
+
+#define TPM_ORD_PCR_EXTEND 20
+#define EXTEND_PCR_RESULT_SIZE 34
+#define EXTEND_PCR_RESULT_BODY_SIZE 20
+static const struct tpm_input_header pcrextend_header = {
+	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
+	.length = cpu_to_be32(34),
+	.ordinal = cpu_to_be32(TPM_ORD_PCR_EXTEND)
+};
+
+static int tpm1_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash,
+			   char *log_msg)
+{
+	struct tpm_buf buf;
+	int rc;
+
+	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCR_EXTEND);
+	if (rc)
+		return rc;
+
+	tpm_buf_append_u32(&buf, pcr_idx);
+	tpm_buf_append(&buf, hash, TPM_DIGEST_SIZE);
+
+	rc = tpm_transmit_cmd(chip, NULL, buf.data, EXTEND_PCR_RESULT_SIZE,
+			      EXTEND_PCR_RESULT_BODY_SIZE, 0, log_msg);
+	tpm_buf_destroy(&buf);
+	return rc;
+}
+
+/**
+ * tpm_pcr_extend - extend a PCR value in SHA1 bank.
+ * @chip:	a &struct tpm_chip instance, %NULL for the default chip
+ * @pcr_idx:	the PCR to be retrieved
+ * @hash:	the hash value used to extend the PCR value
+ *
+ * Note: with TPM 2.0 extends also those banks with a known digest size to the
+ * cryto subsystem in order to prevent malicious use of those PCR banks. In the
+ * future we should dynamically determine digest sizes.
+ *
+ * Return: same as with tpm_transmit_cmd()
+ */
+int tpm_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash)
+{
+	int rc;
+	struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)];
+	u32 count = 0;
+	int i;
+
+	chip = tpm_find_get_ops(chip);
+	if (!chip)
+		return -ENODEV;
+
+	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+		memset(digest_list, 0, sizeof(digest_list));
+
+		for (i = 0; i < ARRAY_SIZE(chip->active_banks) &&
+			    chip->active_banks[i] != TPM2_ALG_ERROR; i++) {
+			digest_list[i].alg_id = chip->active_banks[i];
+			memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE);
+			count++;
+		}
+
+		rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list);
+		tpm_put_ops(chip);
+		return rc;
+	}
+
+	rc = tpm1_pcr_extend(chip, pcr_idx, hash,
+			     "attempting extend a PCR value");
+	tpm_put_ops(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;
+	u8 dummy[TPM_DIGEST_SIZE];
+
+	duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
+
+	loops = jiffies_to_msecs(duration) / delay_msec;
+
+	rc = tpm_continue_selftest(chip);
+	if (rc == TPM_ERR_INVALID_POSTINIT) {
+		chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED;
+		dev_info(&chip->dev, "TPM not ready (%d)\n", rc);
+	}
+	/* 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 */
+		rc = tpm_pcr_read_dev(chip, 0, dummy);
+
+		/* 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");
+			tpm_msleep(delay_msec);
+			continue;
+		}
+
+		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;
+		tpm_msleep(delay_msec);
+	} while (--loops > 0);
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_do_selftest);
+
+/**
+ * tpm1_auto_startup - Perform the standard automatic TPM initialization
+ *                     sequence
+ * @chip: TPM chip to use
+ *
+ * Returns 0 on success, < 0 in case of fatal error.
+ */
+int tpm1_auto_startup(struct tpm_chip *chip)
+{
+	int rc;
+
+	rc = tpm_get_timeouts(chip);
+	if (rc)
+		goto out;
+	rc = tpm_do_selftest(chip);
+	if (rc) {
+		dev_err(&chip->dev, "TPM self test failed\n");
+		goto out;
+	}
+
+	return rc;
+out:
+	if (rc > 0)
+		rc = -ENODEV;
+	return rc;
+}
+
+/**
+ * tpm_send - send a TPM command
+ * @chip:	a &struct tpm_chip instance, %NULL for the default chip
+ * @cmd:	a TPM command buffer
+ * @buflen:	the length of the TPM command buffer
+ *
+ * Return: same as with tpm_transmit_cmd()
+ */
+int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen)
+{
+	int rc;
+
+	chip = tpm_find_get_ops(chip);
+	if (!chip)
+		return -ENODEV;
+
+	rc = tpm_transmit_cmd(chip, NULL, cmd, buflen, 0, 0,
+			      "attempting to a send a command");
+	tpm_put_ops(chip);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_send);
+
+#define TPM_ORD_SAVESTATE 152
+#define SAVESTATE_RESULT_SIZE 10
+
+static const struct tpm_input_header savestate_header = {
+	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
+	.length = cpu_to_be32(10),
+	.ordinal = cpu_to_be32(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;
+
+	if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
+		return 0;
+
+	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+		tpm2_shutdown(chip, TPM2_SU_STATE);
+		return 0;
+	}
+
+	/* for buggy tpm, flush pcrs with extend to selected dummy */
+	if (tpm_suspend_pcr)
+		rc = tpm1_pcr_extend(chip, tpm_suspend_pcr, dummy_hash,
+				     "extending dummy pcr before suspend");
+
+	/* now do the actual savestate */
+	for (try = 0; try < TPM_RETRY; try++) {
+		cmd.header.in = savestate_header;
+		rc = tpm_transmit_cmd(chip, NULL, &cmd, SAVESTATE_RESULT_SIZE,
+				      0, 0, 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;
+		tpm_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 const struct tpm_input_header tpm_getrandom_header = {
+	.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
+	.length = cpu_to_be32(14),
+	.ordinal = cpu_to_be32(TPM_ORD_GET_RANDOM)
+};
+
+/**
+ * tpm_get_random() - get random bytes from the TPM's RNG
+ * @chip:	a &struct tpm_chip instance, %NULL for the default chip
+ * @out:	destination buffer for the random bytes
+ * @max:	the max number of bytes to write to @out
+ *
+ * Return: same as with tpm_transmit_cmd()
+ */
+int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max)
+{
+	struct tpm_cmd_t tpm_cmd;
+	u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA), rlength;
+	int err, total = 0, retries = 5;
+	u8 *dest = out;
+
+	if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
+		return -EINVAL;
+
+	chip = tpm_find_get_ops(chip);
+	if (!chip)
+		return -ENODEV;
+
+	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+		err = tpm2_get_random(chip, out, max);
+		tpm_put_ops(chip);
+		return err;
+	}
+
+	do {
+		tpm_cmd.header.in = tpm_getrandom_header;
+		tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
+
+		err = tpm_transmit_cmd(chip, NULL, &tpm_cmd,
+				       TPM_GETRANDOM_RESULT_SIZE + num_bytes,
+				       offsetof(struct tpm_getrandom_out,
+						rng_data),
+				       0, "attempting get random");
+		if (err)
+			break;
+
+		recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
+		if (recd > num_bytes) {
+			total = -EFAULT;
+			break;
+		}
+
+		rlength = be32_to_cpu(tpm_cmd.header.out.length);
+		if (rlength < TPM_HEADER_SIZE +
+			      offsetof(struct tpm_getrandom_out, rng_data) +
+			      recd) {
+			total = -EFAULT;
+			break;
+		}
+		memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
+
+		dest += recd;
+		total += recd;
+		num_bytes -= recd;
+	} while (retries-- && total < max);
+
+	tpm_put_ops(chip);
+	return total ? total : -EIO;
+}
+EXPORT_SYMBOL_GPL(tpm_get_random);
+
+/**
+ * tpm_seal_trusted() - seal a trusted key payload
+ * @chip:	a &struct tpm_chip instance, %NULL for the default chip
+ * @options:	authentication values and other options
+ * @payload:	the key data in clear and encrypted form
+ *
+ * Note: only TPM 2.0 chip are supported. TPM 1.x implementation is located in
+ * the keyring subsystem.
+ *
+ * Return: same as with tpm_transmit_cmd()
+ */
+int tpm_seal_trusted(struct tpm_chip *chip, struct trusted_key_payload *payload,
+		     struct trusted_key_options *options)
+{
+	int rc;
+
+	chip = tpm_find_get_ops(chip);
+	if (!chip || !(chip->flags & TPM_CHIP_FLAG_TPM2))
+		return -ENODEV;
+
+	rc = tpm2_seal_trusted(chip, payload, options);
+
+	tpm_put_ops(chip);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_seal_trusted);
+
+/**
+ * tpm_unseal_trusted() - unseal a trusted key
+ * @chip:	a &struct tpm_chip instance, %NULL for the default chip
+ * @options:	authentication values and other options
+ * @payload:	the key data in clear and encrypted form
+ *
+ * Note: only TPM 2.0 chip are supported. TPM 1.x implementation is located in
+ * the keyring subsystem.
+ *
+ * Return: same as with tpm_transmit_cmd()
+ */
+int tpm_unseal_trusted(struct tpm_chip *chip,
+		       struct trusted_key_payload *payload,
+		       struct trusted_key_options *options)
+{
+	int rc;
+
+	chip = tpm_find_get_ops(chip);
+	if (!chip || !(chip->flags & TPM_CHIP_FLAG_TPM2))
+		return -ENODEV;
+
+	rc = tpm2_unseal_trusted(chip, payload, options);
+
+	tpm_put_ops(chip);
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_unseal_trusted);
+
+static int __init tpm_init(void)
+{
+	int rc;
+
+	tpm_class = class_create(THIS_MODULE, "tpm");
+	if (IS_ERR(tpm_class)) {
+		pr_err("couldn't create tpm class\n");
+		return PTR_ERR(tpm_class);
+	}
+
+	tpmrm_class = class_create(THIS_MODULE, "tpmrm");
+	if (IS_ERR(tpmrm_class)) {
+		pr_err("couldn't create tpmrm class\n");
+		class_destroy(tpm_class);
+		return PTR_ERR(tpmrm_class);
+	}
+
+	rc = alloc_chrdev_region(&tpm_devt, 0, 2*TPM_NUM_DEVICES, "tpm");
+	if (rc < 0) {
+		pr_err("tpm: failed to allocate char dev region\n");
+		class_destroy(tpmrm_class);
+		class_destroy(tpm_class);
+		return rc;
+	}
+
+	return 0;
+}
+
+static void __exit tpm_exit(void)
+{
+	idr_destroy(&dev_nums_idr);
+	class_destroy(tpm_class);
+	class_destroy(tpmrm_class);
+	unregister_chrdev_region(tpm_devt, 2*TPM_NUM_DEVICES);
+}
+
+subsys_initcall(tpm_init);
+module_exit(tpm_exit);
+
+MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
+MODULE_DESCRIPTION("TPM Driver");
+MODULE_VERSION("2.0");
+MODULE_LICENSE("GPL");