Patchwork [U-Boot,v2,2/3] tpm: Add Infineon slb9635_i2c TPM driver

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Submitter Simon Glass
Date April 12, 2013, 8:44 p.m.
Message ID <1365799498-17895-2-git-send-email-sjg@chromium.org>
Download mbox | patch
Permalink /patch/236186/
State Accepted
Delegated to: Tom Rini
Headers show

Comments

Simon Glass - April 12, 2013, 8:44 p.m.
From: Rong Chang <rongchang@chromium.org>

Add a driver for the I2C TPM from Infineon.

Signed-off-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Rong Chang <rongchang@chromium.org>
Signed-off-by: Tom Wai-Hong Tam <waihong@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
---
Changes in v2:
- Tidy up new checkpatch warnings
- Use udelay() instead of usleep()
- Use new form of i2c_get_bus_num_fdt()

 Makefile                                |   2 +-
 drivers/tpm/Makefile                    |   4 +
 drivers/tpm/slb9635_i2c/compatibility.h |  51 +++
 drivers/tpm/slb9635_i2c/tpm.c           | 453 ++++++++++++++++++++++++++
 drivers/tpm/slb9635_i2c/tpm.h           | 161 +++++++++
 drivers/tpm/slb9635_i2c/tpm_tis_i2c.c   | 561 ++++++++++++++++++++++++++++++++
 drivers/tpm/tis_i2c.c                   | 181 +++++++++++
 include/fdtdec.h                        |   1 +
 lib/fdtdec.c                            |   1 +
 9 files changed, 1414 insertions(+), 1 deletion(-)
 create mode 100644 drivers/tpm/slb9635_i2c/compatibility.h
 create mode 100644 drivers/tpm/slb9635_i2c/tpm.c
 create mode 100644 drivers/tpm/slb9635_i2c/tpm.h
 create mode 100644 drivers/tpm/slb9635_i2c/tpm_tis_i2c.c
 create mode 100644 drivers/tpm/tis_i2c.c

Patch

diff --git a/Makefile b/Makefile
index db7561c..6547bc0 100644
--- a/Makefile
+++ b/Makefile
@@ -314,7 +314,7 @@  endif
 LIBS-y += drivers/rtc/librtc.o
 LIBS-y += drivers/serial/libserial.o
 LIBS-y += drivers/sound/libsound.o
-LIBS-$(CONFIG_GENERIC_LPC_TPM) += drivers/tpm/libtpm.o
+LIBS-y += drivers/tpm/libtpm.o
 LIBS-y += drivers/twserial/libtws.o
 LIBS-y += drivers/usb/eth/libusb_eth.o
 LIBS-y += drivers/usb/gadget/libusb_gadget.o
diff --git a/drivers/tpm/Makefile b/drivers/tpm/Makefile
index be11c8b..e8c159c 100644
--- a/drivers/tpm/Makefile
+++ b/drivers/tpm/Makefile
@@ -23,7 +23,11 @@  include $(TOPDIR)/config.mk
 
 LIB := $(obj)libtpm.o
 
+$(shell mkdir -p $(obj)slb9635_i2c)
+
 COBJS-$(CONFIG_GENERIC_LPC_TPM) = generic_lpc_tpm.o
+COBJS-$(CONFIG_INFINEON_TPM_I2C) += tis_i2c.o slb9635_i2c/tpm.o
+COBJS-$(CONFIG_INFINEON_TPM_I2C) += slb9635_i2c/tpm_tis_i2c.o
 
 COBJS	:= $(COBJS-y)
 SRCS	:= $(COBJS:.o=.c)
diff --git a/drivers/tpm/slb9635_i2c/compatibility.h b/drivers/tpm/slb9635_i2c/compatibility.h
new file mode 100644
index 0000000..62dc9fa
--- /dev/null
+++ b/drivers/tpm/slb9635_i2c/compatibility.h
@@ -0,0 +1,51 @@ 
+/*
+ * Copyright (C) 2011 Infineon Technologies
+ *
+ * Authors:
+ * Peter Huewe <huewe.external@infineon.com>
+ *
+ * Version: 2.1.1
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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
+ */
+
+#ifndef _COMPATIBILITY_H_
+#define _COMPATIBILITY_H_
+
+/* all includes from U-Boot */
+#include <linux/types.h>
+#include <linux/unaligned/be_byteshift.h>
+#include <asm-generic/errno.h>
+#include <compiler.h>
+#include <common.h>
+
+/* extended error numbers from linux (see errno.h) */
+#define	ECANCELED	125	/* Operation Canceled */
+
+#define msleep(t) udelay((t)*1000)
+
+/* Timer frequency. Corresponds to msec timer resolution*/
+#define HZ             1000
+
+#define dev_dbg(dev, format, arg...) debug(format, ##arg)
+#define dev_err(dev, format, arg...) printf(format, ##arg)
+#define dev_info(dev, format, arg...) debug(format, ##arg)
+#define dbg_printf debug
+
+#endif
diff --git a/drivers/tpm/slb9635_i2c/tpm.c b/drivers/tpm/slb9635_i2c/tpm.c
new file mode 100644
index 0000000..496c48e
--- /dev/null
+++ b/drivers/tpm/slb9635_i2c/tpm.c
@@ -0,0 +1,453 @@ 
+/*
+ * Copyright (C) 2011 Infineon Technologies
+ *
+ * Authors:
+ * Peter Huewe <huewe.external@infineon.com>
+ *
+ * Description:
+ * Device driver for TCG/TCPA TPM (trusted platform module).
+ * Specifications at www.trustedcomputinggroup.org
+ *
+ * It is based on the Linux kernel driver tpm.c from Leendert van
+ * Dorn, Dave Safford, Reiner Sailer, and Kyleen Hall.
+ *
+ * Version: 2.1.1
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ *
+ * 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 <malloc.h>
+#include "tpm.h"
+
+/* global structure for tpm chip data */
+struct tpm_chip g_chip;
+
+enum tpm_duration {
+	TPM_SHORT = 0,
+	TPM_MEDIUM = 1,
+	TPM_LONG = 2,
+	TPM_UNDEFINED,
+};
+
+#define TPM_MAX_ORDINAL 243
+#define TPM_MAX_PROTECTED_ORDINAL 12
+#define TPM_PROTECTED_ORDINAL_MASK 0xFF
+
+/*
+ * 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_protected_ordinal_duration[TPM_MAX_PROTECTED_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,
+};
+
+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 milliseconds to wait
+ */
+unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
+{
+	int duration_idx = TPM_UNDEFINED;
+	int duration = 0;
+
+	if (ordinal < TPM_MAX_ORDINAL)
+		duration_idx = tpm_ordinal_duration[ordinal];
+	else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
+		 TPM_MAX_PROTECTED_ORDINAL)
+		duration_idx =
+		    tpm_protected_ordinal_duration[ordinal &
+						   TPM_PROTECTED_ORDINAL_MASK];
+
+	if (duration_idx != TPM_UNDEFINED)
+		duration = chip->vendor.duration[duration_idx];
+	if (duration <= 0)
+		return 2 * 60 * HZ; /*two minutes timeout*/
+	else
+		return duration;
+}
+
+#define TPM_CMD_COUNT_BYTE 2
+#define TPM_CMD_ORDINAL_BYTE 6
+
+ssize_t tpm_transmit(const unsigned char *buf, size_t bufsiz)
+{
+	ssize_t rc;
+	u32 count, ordinal;
+	unsigned long start, stop;
+
+	struct tpm_chip *chip = &g_chip;
+
+	/* switch endianess: big->little */
+	count = get_unaligned_be32(buf + TPM_CMD_COUNT_BYTE);
+	ordinal = get_unaligned_be32(buf + TPM_CMD_ORDINAL_BYTE);
+
+	if (count == 0) {
+		dev_err(chip->dev, "no data\n");
+		return -ENODATA;
+	}
+	if (count > bufsiz) {
+		dev_err(chip->dev,
+			"invalid count value %x %zx\n", count, bufsiz);
+		return -E2BIG;
+	}
+
+	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;
+
+	start = get_timer(0);
+	stop = tpm_calc_ordinal_duration(chip, ordinal);
+	do {
+		dbg_printf("waiting for status...\n");
+		u8 status = chip->vendor.status(chip);
+		if ((status & chip->vendor.req_complete_mask) ==
+		    chip->vendor.req_complete_val) {
+			dbg_printf("...got it;\n");
+			goto out_recv;
+		}
+
+		if ((status == chip->vendor.req_canceled)) {
+			dev_err(chip->dev, "Operation Canceled\n");
+			rc = -ECANCELED;
+			goto out;
+		}
+		msleep(TPM_TIMEOUT);
+	} while (get_timer(start) < stop);
+
+	chip->vendor.cancel(chip);
+	dev_err(chip->dev, "Operation Timed out\n");
+	rc = -ETIME;
+	goto out;
+
+out_recv:
+
+	dbg_printf("out_recv: reading response...\n");
+	rc = chip->vendor.recv(chip, (u8 *)buf, TPM_BUFSIZE);
+	if (rc < 0)
+		dev_err(chip->dev, "tpm_transmit: tpm_recv: error %zd\n", rc);
+out:
+	return rc;
+}
+
+#define TPM_ERROR_SIZE 10
+
+enum tpm_capabilities {
+	TPM_CAP_PROP = cpu_to_be32(5),
+};
+
+enum tpm_sub_capabilities {
+	TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
+	TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
+};
+
+struct tpm_chip *tpm_register_hardware(const struct tpm_vendor_specific *entry)
+{
+	struct tpm_chip *chip;
+
+	/* Driver specific per-device data */
+	chip = &g_chip;
+	memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
+	chip->is_open = 1;
+
+	return chip;
+}
+
+int tpm_open(uint32_t dev_addr)
+{
+	int rc;
+	if (g_chip.is_open)
+		return -EBUSY;
+	rc = tpm_vendor_init(dev_addr);
+	if (rc < 0)
+		g_chip.is_open = 0;
+	return rc;
+}
+
+void tpm_close(void)
+{
+	if (g_chip.is_open) {
+		tpm_vendor_cleanup(&g_chip);
+		g_chip.is_open = 0;
+	}
+}
diff --git a/drivers/tpm/slb9635_i2c/tpm.h b/drivers/tpm/slb9635_i2c/tpm.h
new file mode 100644
index 0000000..9ddee86
--- /dev/null
+++ b/drivers/tpm/slb9635_i2c/tpm.h
@@ -0,0 +1,161 @@ 
+/*
+ * Copyright (C) 2011 Infineon Technologies
+ *
+ * Authors:
+ * Peter Huewe <huewe.external@infineon.com>
+ *
+ * Version: 2.1.1
+ *
+ * Description:
+ * Device driver for TCG/TCPA TPM (trusted platform module).
+ * Specifications at www.trustedcomputinggroup.org
+ *
+ * It is based on the Linux kernel driver tpm.c from Leendert van
+ * Dorn, Dave Safford, Reiner Sailer, and Kyleen Hall.
+ *
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ *
+ * 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
+ */
+
+#ifndef _TPM_H_
+#define _TPM_H_
+
+#include <linux/compiler.h>
+
+#include "compatibility.h"
+
+enum tpm_timeout {
+	TPM_TIMEOUT = 5,	/* msecs */
+};
+
+/* Size of external transmit buffer (used in tpm_transmit)*/
+#define TPM_BUFSIZE 4096
+
+/* Index of fields in TPM command buffer */
+#define TPM_CMD_SIZE_BYTE 2
+#define TPM_CMD_ORDINAL_BYTE 6
+
+/* Index of Count field in TPM response buffer */
+#define TPM_RSP_SIZE_BYTE 2
+#define TPM_RSP_RC_BYTE 6
+
+struct tpm_chip;
+
+struct tpm_vendor_specific {
+	const u8 req_complete_mask;
+	const u8 req_complete_val;
+	const u8 req_canceled;
+	int irq;
+	int (*recv) (struct tpm_chip *, u8 *, size_t);
+	int (*send) (struct tpm_chip *, u8 *, size_t);
+	void (*cancel) (struct tpm_chip *);
+	 u8(*status) (struct tpm_chip *);
+	int locality;
+	unsigned long timeout_a, timeout_b, timeout_c, timeout_d; /* msec */
+	unsigned long duration[3];	/* msec */
+};
+
+struct tpm_chip {
+	int is_open;
+	struct tpm_vendor_specific vendor;
+};
+
+struct tpm_input_header {
+	__be16 tag;
+	__be32 length;
+	__be32 ordinal;
+} __packed;
+
+struct tpm_output_header {
+	__be16 tag;
+	__be32 length;
+	__be32 return_code;
+} __packed;
+
+struct timeout_t {
+	__be32 a;
+	__be32 b;
+	__be32 c;
+	__be32 d;
+} __packed;
+
+struct duration_t {
+	__be32 tpm_short;
+	__be32 tpm_medium;
+	__be32 tpm_long;
+} __packed;
+
+union cap_t {
+	struct timeout_t timeout;
+	struct duration_t duration;
+};
+
+struct tpm_getcap_params_in {
+	__be32 cap;
+	__be32 subcap_size;
+	__be32 subcap;
+} __packed;
+
+struct tpm_getcap_params_out {
+	__be32 cap_size;
+	union cap_t cap;
+} __packed;
+
+union tpm_cmd_header {
+	struct tpm_input_header in;
+	struct tpm_output_header out;
+};
+
+union tpm_cmd_params {
+	struct tpm_getcap_params_out getcap_out;
+	struct tpm_getcap_params_in getcap_in;
+};
+
+struct tpm_cmd_t {
+	union tpm_cmd_header header;
+	union tpm_cmd_params params;
+} __packed;
+
+
+/* ---------- Interface for TPM vendor ------------ */
+
+extern struct tpm_chip *tpm_register_hardware(
+	const struct tpm_vendor_specific *);
+
+extern int tpm_vendor_init(uint32_t dev_addr);
+
+extern void tpm_vendor_cleanup(struct tpm_chip *chip);
+
+/* ---------- Interface for TDDL ------------------- */
+
+/*
+ * if dev_addr != 0 - redefines TPM device address
+ * Returns < 0 on error, 0 on success.
+ */
+extern int tpm_open(uint32_t dev_addr);
+
+extern void tpm_close(void);
+
+/*
+ * Transmit bufsiz bytes out of buf to TPM and get results back in buf, too.
+ * Returns < 0 on error, 0 on success.
+ */
+extern ssize_t tpm_transmit(const unsigned char *buf, size_t bufsiz);
+
+#endif
diff --git a/drivers/tpm/slb9635_i2c/tpm_tis_i2c.c b/drivers/tpm/slb9635_i2c/tpm_tis_i2c.c
new file mode 100644
index 0000000..82a41bf
--- /dev/null
+++ b/drivers/tpm/slb9635_i2c/tpm_tis_i2c.c
@@ -0,0 +1,561 @@ 
+/*
+ * Copyright (C) 2011 Infineon Technologies
+ *
+ * Authors:
+ * Peter Huewe <huewe.external@infineon.com>
+ *
+ * Description:
+ * Device driver for TCG/TCPA TPM (trusted platform module).
+ * Specifications at www.trustedcomputinggroup.org
+ *
+ * This device driver implements the TPM interface as defined in
+ * the TCG TPM Interface Spec version 1.2, revision 1.0 and the
+ * Infineon I2C Protocol Stack Specification v0.20.
+ *
+ * It is based on the Linux kernel driver tpm.c from Leendert van
+ * Dorn, Dave Safford, Reiner Sailer, and Kyleen Hall.
+ *
+ * Version: 2.1.1
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ *
+ * 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 <common.h>
+#include <i2c.h>
+#include <linux/types.h>
+
+#include "compatibility.h"
+#include "tpm.h"
+
+/* max. buffer size supported by our tpm */
+#ifdef TPM_BUFSIZE
+#undef TPM_BUFSIZE
+#endif
+#define TPM_BUFSIZE 1260
+/* Address of the TPM on the I2C bus */
+#define TPM_I2C_ADDR 0x20
+/* max. number of iterations after i2c NAK */
+#define MAX_COUNT 3
+
+#define SLEEP_DURATION 60 /*in usec*/
+
+/* max. number of iterations after i2c NAK for 'long' commands
+ * we need this especially for sending TPM_READY, since the cleanup after the
+ * transtion to the ready state may take some time, but it is unpredictable
+ * how long it will take.
+ */
+#define MAX_COUNT_LONG 50
+
+#define SLEEP_DURATION_LONG 210 /* in usec */
+
+/* expected value for DIDVID register */
+#define TPM_TIS_I2C_DID_VID 0x000b15d1L
+
+/* Structure to store I2C TPM specific stuff */
+struct tpm_inf_dev {
+	uint addr;
+	u8 buf[TPM_BUFSIZE + sizeof(u8)];	/* max. buffer size + addr */
+};
+
+static struct tpm_inf_dev tpm_dev = {
+	.addr = TPM_I2C_ADDR
+};
+
+/*
+ * iic_tpm_read() - read from TPM register
+ * @addr: register address to read from
+ * @buffer: provided by caller
+ * @len: number of bytes to read
+ *
+ * Read len bytes from TPM register and put them into
+ * buffer (little-endian format, i.e. first byte is put into buffer[0]).
+ *
+ * NOTE: TPM is big-endian for multi-byte values. Multi-byte
+ * values have to be swapped.
+ *
+ * Return -EIO on error, 0 on success.
+ */
+int iic_tpm_read(u8 addr, u8 *buffer, size_t len)
+{
+	int rc;
+	int count;
+	uint myaddr = addr;
+	/* we have to use uint here, uchar hangs the board */
+
+	for (count = 0; count < MAX_COUNT; count++) {
+		rc = i2c_write(tpm_dev.addr, 0, 0, (uchar *)&myaddr, 1);
+		if (rc == 0)
+			break; /*success, break to skip sleep*/
+
+		udelay(SLEEP_DURATION);
+	}
+
+	if (rc)
+		return -rc;
+
+	/* After the TPM has successfully received the register address it needs
+	 * some time, thus we're sleeping here again, before retrieving the data
+	 */
+	for (count = 0; count < MAX_COUNT; count++) {
+		udelay(SLEEP_DURATION);
+		rc = i2c_read(tpm_dev.addr, 0, 0, buffer, len);
+		if (rc == 0)
+			break; /*success, break to skip sleep*/
+	}
+
+	if (rc)
+		return -rc;
+
+	return 0;
+}
+
+static int iic_tpm_write_generic(u8 addr, u8 *buffer, size_t len,
+				unsigned int sleep_time,
+				u8 max_count)
+{
+	int rc = 0;
+	int count;
+
+	/* prepare send buffer */
+	tpm_dev.buf[0] = addr;
+	memcpy(&(tpm_dev.buf[1]), buffer, len);
+
+	for (count = 0; count < max_count; count++) {
+		rc = i2c_write(tpm_dev.addr, 0, 0, tpm_dev.buf, len + 1);
+		if (rc == 0)
+			break; /*success, break to skip sleep*/
+
+		udelay(sleep_time);
+	}
+
+	if (rc)
+		return -rc;
+
+	return 0;
+}
+
+/*
+ * iic_tpm_write() - write to TPM register
+ * @addr: register address to write to
+ * @buffer: containing data to be written
+ * @len: number of bytes to write
+ *
+ * Write len bytes from provided buffer to TPM register (little
+ * endian format, i.e. buffer[0] is written as first byte).
+ *
+ * NOTE: TPM is big-endian for multi-byte values. Multi-byte
+ * values have to be swapped.
+ *
+ * NOTE: use this function instead of the iic_tpm_write_generic function.
+ *
+ * Return -EIO on error, 0 on success
+ */
+static int iic_tpm_write(u8 addr, u8 *buffer, size_t len)
+{
+	return iic_tpm_write_generic(addr, buffer, len, SLEEP_DURATION,
+			MAX_COUNT);
+}
+
+/*
+ * This function is needed especially for the cleanup situation after
+ * sending TPM_READY
+ * */
+static int iic_tpm_write_long(u8 addr, u8 *buffer, size_t len)
+{
+	return iic_tpm_write_generic(addr, buffer, len, SLEEP_DURATION_LONG,
+			MAX_COUNT_LONG);
+}
+
+#define TPM_HEADER_SIZE 10
+
+enum tis_access {
+	TPM_ACCESS_VALID = 0x80,
+	TPM_ACCESS_ACTIVE_LOCALITY = 0x20,
+	TPM_ACCESS_REQUEST_PENDING = 0x04,
+	TPM_ACCESS_REQUEST_USE = 0x02,
+};
+
+enum tis_status {
+	TPM_STS_VALID = 0x80,
+	TPM_STS_COMMAND_READY = 0x40,
+	TPM_STS_GO = 0x20,
+	TPM_STS_DATA_AVAIL = 0x10,
+	TPM_STS_DATA_EXPECT = 0x08,
+};
+
+enum tis_defaults {
+	TIS_SHORT_TIMEOUT = 750,	/* ms */
+	TIS_LONG_TIMEOUT = 2000,	/* 2 sec */
+};
+
+#define	TPM_ACCESS(l)			(0x0000 | ((l) << 4))
+#define	TPM_STS(l)			(0x0001 | ((l) << 4))
+#define	TPM_DATA_FIFO(l)		(0x0005 | ((l) << 4))
+#define	TPM_DID_VID(l)			(0x0006 | ((l) << 4))
+
+static int check_locality(struct tpm_chip *chip, int loc)
+{
+	u8 buf;
+	int rc;
+
+	rc = iic_tpm_read(TPM_ACCESS(loc), &buf, 1);
+	if (rc < 0)
+		return rc;
+
+	if ((buf & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
+		(TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) {
+		chip->vendor.locality = loc;
+		return loc;
+	}
+
+	return -1;
+}
+
+static void release_locality(struct tpm_chip *chip, int loc, int force)
+{
+	u8 buf;
+	if (iic_tpm_read(TPM_ACCESS(loc), &buf, 1) < 0)
+		return;
+
+	if (force || (buf & (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) ==
+			(TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) {
+		buf = TPM_ACCESS_ACTIVE_LOCALITY;
+		iic_tpm_write(TPM_ACCESS(loc), &buf, 1);
+	}
+}
+
+static int request_locality(struct tpm_chip *chip, int loc)
+{
+	unsigned long start, stop;
+	u8 buf = TPM_ACCESS_REQUEST_USE;
+
+	if (check_locality(chip, loc) >= 0)
+		return loc; /* we already have the locality */
+
+	iic_tpm_write(TPM_ACCESS(loc), &buf, 1);
+
+	/* wait for burstcount */
+	start = get_timer(0);
+	stop = chip->vendor.timeout_a;
+	do {
+		if (check_locality(chip, loc) >= 0)
+			return loc;
+		msleep(TPM_TIMEOUT);
+	} while (get_timer(start) < stop);
+
+	return -1;
+}
+
+static u8 tpm_tis_i2c_status(struct tpm_chip *chip)
+{
+	/* NOTE: since i2c read may fail, return 0 in this case --> time-out */
+	u8 buf;
+	if (iic_tpm_read(TPM_STS(chip->vendor.locality), &buf, 1) < 0)
+		return 0;
+	else
+		return buf;
+}
+
+static void tpm_tis_i2c_ready(struct tpm_chip *chip)
+{
+	/* this causes the current command to be aborted */
+	u8 buf = TPM_STS_COMMAND_READY;
+	iic_tpm_write_long(TPM_STS(chip->vendor.locality), &buf, 1);
+}
+
+static ssize_t get_burstcount(struct tpm_chip *chip)
+{
+	unsigned long start, stop;
+	ssize_t burstcnt;
+	u8 buf[3];
+
+	/* wait for burstcount */
+	/* which timeout value, spec has 2 answers (c & d) */
+	start = get_timer(0);
+	stop = chip->vendor.timeout_d;
+	do {
+		/* Note: STS is little endian */
+		if (iic_tpm_read(TPM_STS(chip->vendor.locality) + 1, buf, 3)
+				< 0)
+			burstcnt = 0;
+		else
+			burstcnt = (buf[2] << 16) + (buf[1] << 8) + buf[0];
+
+		if (burstcnt)
+			return burstcnt;
+		msleep(TPM_TIMEOUT);
+	} while (get_timer(start) < stop);
+
+	return -EBUSY;
+}
+
+static int wait_for_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
+			int *status)
+{
+	unsigned long start, stop;
+
+	/* check current status */
+	*status = tpm_tis_i2c_status(chip);
+	if ((*status & mask) == mask)
+		return 0;
+
+	start = get_timer(0);
+	stop = timeout;
+	do {
+		msleep(TPM_TIMEOUT);
+		*status = tpm_tis_i2c_status(chip);
+		if ((*status & mask) == mask)
+			return 0;
+
+	} while (get_timer(start) < stop);
+
+	return -ETIME;
+}
+
+static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
+{
+	size_t size = 0;
+	ssize_t burstcnt;
+	int rc;
+
+	while (size < count) {
+		burstcnt = get_burstcount(chip);
+
+		/* burstcount < 0 = tpm is busy */
+		if (burstcnt < 0)
+			return burstcnt;
+
+		/* limit received data to max. left */
+		if (burstcnt > (count - size))
+			burstcnt = count - size;
+
+		rc = iic_tpm_read(TPM_DATA_FIFO(chip->vendor.locality),
+				  &(buf[size]),
+				  burstcnt);
+		if (rc == 0)
+			size += burstcnt;
+	}
+
+	return size;
+}
+
+static int tpm_tis_i2c_recv(struct tpm_chip *chip, u8 *buf, size_t count)
+{
+	int size = 0;
+	int expected, status;
+
+	if (count < TPM_HEADER_SIZE) {
+		size = -EIO;
+		goto out;
+	}
+
+	/* read first 10 bytes, including tag, paramsize, and result */
+	size = recv_data(chip, buf, TPM_HEADER_SIZE);
+	if (size < TPM_HEADER_SIZE) {
+		dev_err(chip->dev, "Unable to read header\n");
+		goto out;
+	}
+
+	expected = get_unaligned_be32(buf + TPM_RSP_SIZE_BYTE);
+	if ((size_t)expected > count) {
+		size = -EIO;
+		goto out;
+	}
+
+	size += recv_data(chip, &buf[TPM_HEADER_SIZE],
+				expected - TPM_HEADER_SIZE);
+	if (size < expected) {
+		dev_err(chip->dev, "Unable to read remainder of result\n");
+		size = -ETIME;
+		goto out;
+	}
+
+	wait_for_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c, &status);
+	if (status & TPM_STS_DATA_AVAIL) {	/* retry? */
+		dev_err(chip->dev, "Error left over data\n");
+		size = -EIO;
+		goto out;
+	}
+
+out:
+	tpm_tis_i2c_ready(chip);
+	/* The TPM needs some time to clean up here,
+	 * so we sleep rather than keeping the bus busy
+	 */
+	udelay(2000);
+	release_locality(chip, chip->vendor.locality, 0);
+
+	return size;
+}
+
+static int tpm_tis_i2c_send(struct tpm_chip *chip, u8 *buf, size_t len)
+{
+	int rc, status;
+	ssize_t burstcnt;
+	size_t count = 0;
+	u8 sts = TPM_STS_GO;
+
+	if (len > TPM_BUFSIZE)
+		return -E2BIG; /* command is too long for our tpm, sorry */
+
+	if (request_locality(chip, 0) < 0)
+		return -EBUSY;
+
+	status = tpm_tis_i2c_status(chip);
+	if ((status & TPM_STS_COMMAND_READY) == 0) {
+		tpm_tis_i2c_ready(chip);
+		if (wait_for_stat
+		    (chip, TPM_STS_COMMAND_READY,
+		     chip->vendor.timeout_b, &status) < 0) {
+			rc = -ETIME;
+			goto out_err;
+		}
+	}
+
+	while (count < len - 1) {
+		burstcnt = get_burstcount(chip);
+
+		/* burstcount < 0 = tpm is busy */
+		if (burstcnt < 0)
+			return burstcnt;
+
+		if (burstcnt > (len-1-count))
+			burstcnt = len-1-count;
+
+#ifdef CONFIG_TPM_I2C_BURST_LIMITATION
+		if (burstcnt > CONFIG_TPM_I2C_BURST_LIMITATION)
+			burstcnt = CONFIG_TPM_I2C_BURST_LIMITATION;
+#endif /* CONFIG_TPM_I2C_BURST_LIMITATION */
+
+		rc = iic_tpm_write(TPM_DATA_FIFO(chip->vendor.locality),
+				   &(buf[count]), burstcnt);
+		if (rc == 0)
+			count += burstcnt;
+
+		wait_for_stat(chip, TPM_STS_VALID,
+			      chip->vendor.timeout_c, &status);
+
+		if ((status & TPM_STS_DATA_EXPECT) == 0) {
+			rc = -EIO;
+			goto out_err;
+		}
+	}
+
+	/* write last byte */
+	iic_tpm_write(TPM_DATA_FIFO(chip->vendor.locality), &(buf[count]), 1);
+	wait_for_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c, &status);
+	if ((status & TPM_STS_DATA_EXPECT) != 0) {
+		rc = -EIO;
+		goto out_err;
+	}
+
+	/* go and do it */
+	iic_tpm_write(TPM_STS(chip->vendor.locality), &sts, 1);
+
+	return len;
+out_err:
+	tpm_tis_i2c_ready(chip);
+	/* The TPM needs some time to clean up here,
+	 * so we sleep rather than keeping the bus busy
+	 */
+	udelay(2000);
+	release_locality(chip, chip->vendor.locality, 0);
+
+	return rc;
+}
+
+static struct tpm_vendor_specific tpm_tis_i2c = {
+	.status = tpm_tis_i2c_status,
+	.recv = tpm_tis_i2c_recv,
+	.send = tpm_tis_i2c_send,
+	.cancel = tpm_tis_i2c_ready,
+	.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
+	.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
+	.req_canceled = TPM_STS_COMMAND_READY,
+};
+
+/* initialisation of i2c tpm */
+
+
+int tpm_vendor_init(uint32_t dev_addr)
+{
+	u32 vendor;
+	uint old_addr;
+	int rc = 0;
+	struct tpm_chip *chip;
+
+	old_addr = tpm_dev.addr;
+	if (dev_addr != 0)
+		tpm_dev.addr = dev_addr;
+
+	chip = tpm_register_hardware(&tpm_tis_i2c);
+	if (chip < 0) {
+		rc = -ENODEV;
+		goto out_err;
+	}
+
+	/* Disable interrupts (not supported) */
+	chip->vendor.irq = 0;
+
+	/* Default timeouts */
+	chip->vendor.timeout_a = TIS_SHORT_TIMEOUT;
+	chip->vendor.timeout_b = TIS_LONG_TIMEOUT;
+	chip->vendor.timeout_c = TIS_SHORT_TIMEOUT;
+	chip->vendor.timeout_d = TIS_SHORT_TIMEOUT;
+
+	if (request_locality(chip, 0) != 0) {
+		rc = -ENODEV;
+		goto out_err;
+	}
+
+	/* read four bytes from DID_VID register */
+	if (iic_tpm_read(TPM_DID_VID(0), (uchar *)&vendor, 4) < 0) {
+		rc = -EIO;
+		goto out_release;
+	}
+
+	/* create DID_VID register value, after swapping to little-endian */
+	vendor = be32_to_cpu(vendor);
+
+	if (vendor != TPM_TIS_I2C_DID_VID) {
+		rc = -ENODEV;
+		goto out_release;
+	}
+
+	dev_info(dev, "1.2 TPM (device-id 0x%X)\n", vendor >> 16);
+
+	/*
+	 * A timeout query to TPM can be placed here.
+	 * Standard timeout values are used so far
+	 */
+
+	return 0;
+
+out_release:
+	release_locality(chip, 0, 1);
+
+out_err:
+	tpm_dev.addr = old_addr;
+	return rc;
+}
+
+void tpm_vendor_cleanup(struct tpm_chip *chip)
+{
+	release_locality(chip, chip->vendor.locality, 1);
+}
diff --git a/drivers/tpm/tis_i2c.c b/drivers/tpm/tis_i2c.c
new file mode 100644
index 0000000..e818fba
--- /dev/null
+++ b/drivers/tpm/tis_i2c.c
@@ -0,0 +1,181 @@ 
+/*
+ * Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <config.h>
+#include <common.h>
+#include <fdtdec.h>
+#include <i2c.h>
+#include "slb9635_i2c/tpm.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* TPM configuration */
+struct tpm {
+	int i2c_bus;
+	int slave_addr;
+	char inited;
+	int old_bus;
+} tpm;
+
+
+static int tpm_select(void)
+{
+	int ret;
+
+	tpm.old_bus = i2c_get_bus_num();
+	if (tpm.old_bus != tpm.i2c_bus) {
+		ret = i2c_set_bus_num(tpm.i2c_bus);
+		if (ret) {
+			debug("%s: Fail to set i2c bus %d\n", __func__,
+			      tpm.i2c_bus);
+			return -1;
+		}
+	}
+	return 0;
+}
+
+static int tpm_deselect(void)
+{
+	int ret;
+
+	if (tpm.old_bus != i2c_get_bus_num()) {
+		ret = i2c_set_bus_num(tpm.old_bus);
+		if (ret) {
+			debug("%s: Fail to restore i2c bus %d\n",
+			      __func__, tpm.old_bus);
+			return -1;
+		}
+	}
+	tpm.old_bus = -1;
+	return 0;
+}
+
+/**
+ * Decode TPM configuration.
+ *
+ * @param dev	Returns a configuration of TPM device
+ * @return 0 if ok, -1 on error
+ */
+static int tpm_decode_config(struct tpm *dev)
+{
+#ifdef CONFIG_OF_CONTROL
+	const void *blob = gd->fdt_blob;
+	int node, parent;
+	int i2c_bus;
+
+	node = fdtdec_next_compatible(blob, 0, COMPAT_INFINEON_SLB9635_TPM);
+	if (node < 0) {
+		debug("%s: Node not found\n", __func__);
+		return -1;
+	}
+	parent = fdt_parent_offset(blob, node);
+	if (parent < 0) {
+		debug("%s: Cannot find node parent\n", __func__);
+		return -1;
+	}
+	i2c_bus = i2c_get_bus_num_fdt(parent);
+	if (i2c_bus < 0)
+		return -1;
+	dev->i2c_bus = i2c_bus;
+	dev->slave_addr = fdtdec_get_addr(blob, node, "reg");
+#else
+	dev->i2c_bus = CONFIG_INFINEON_TPM_I2C_BUS;
+	dev->slave_addr = CONFIG_INFINEON_TPM_I2C_ADDR;
+#endif
+	return 0;
+}
+
+int tis_init(void)
+{
+	if (tpm.inited)
+		return 0;
+
+	if (tpm_decode_config(&tpm))
+		return -1;
+
+	if (tpm_select())
+		return -1;
+
+	/*
+	 * Probe TPM twice; the first probing might fail because TPM is asleep,
+	 * and the probing can wake up TPM.
+	 */
+	if (i2c_probe(tpm.slave_addr) && i2c_probe(tpm.slave_addr)) {
+		debug("%s: fail to probe i2c addr 0x%x\n", __func__,
+		      tpm.slave_addr);
+		return -1;
+	}
+
+	tpm_deselect();
+
+	tpm.inited = 1;
+
+	return 0;
+}
+
+int tis_open(void)
+{
+	int rc;
+
+	if (!tpm.inited)
+		return -1;
+
+	if (tpm_select())
+		return -1;
+
+	rc = tpm_open(tpm.slave_addr);
+
+	tpm_deselect();
+
+	return rc;
+}
+
+int tis_close(void)
+{
+	if (!tpm.inited)
+		return -1;
+
+	if (tpm_select())
+		return -1;
+
+	tpm_close();
+
+	tpm_deselect();
+
+	return 0;
+}
+
+int tis_sendrecv(const uint8_t *sendbuf, size_t sbuf_size,
+		uint8_t *recvbuf, size_t *rbuf_len)
+{
+	int len;
+	uint8_t buf[4096];
+
+	if (!tpm.inited)
+		return -1;
+
+	if (sizeof(buf) < sbuf_size)
+		return -1;
+
+	memcpy(buf, sendbuf, sbuf_size);
+
+	if (tpm_select())
+		return -1;
+
+	len = tpm_transmit(buf, sbuf_size);
+
+	tpm_deselect();
+
+	if (len < 10) {
+		*rbuf_len = 0;
+		return -1;
+	}
+
+	memcpy(recvbuf, buf, len);
+	*rbuf_len = len;
+
+	return 0;
+}
diff --git a/include/fdtdec.h b/include/fdtdec.h
index e7e3ff9..39fbdf1 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -90,6 +90,7 @@  enum fdt_compat_id {
 	COMPAT_MAXIM_MAX77686_PMIC,	/* MAX77686 PMIC */
 	COMPAT_GENERIC_SPI_FLASH,	/* Generic SPI Flash chip */
 	COMPAT_MAXIM_98095_CODEC,	/* MAX98095 Codec */
+	COMPAT_INFINEON_SLB9635_TPM,	/* Infineon SLB9635 TPM */
 
 	COMPAT_COUNT,
 };
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index e17dd00..e93743c 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -63,6 +63,7 @@  static const char * const compat_names[COMPAT_COUNT] = {
 	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
 	COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
 	COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
+	COMPAT(INFINEON_SLB9635_TPM, "infineon,slb9635-tpm"),
 };
 
 const char *fdtdec_get_compatible(enum fdt_compat_id id)