diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
index 56e8f1f..c6a4cea 100644
--- a/drivers/char/tpm/Makefile
+++ b/drivers/char/tpm/Makefile
@@ -2,7 +2,7 @@
 # Makefile for the kernel tpm device drivers.
 #
 obj-$(CONFIG_TCG_TPM) += tpm.o
-tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o
+tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o tpm_tis_core.o
 tpm-$(CONFIG_ACPI) += tpm_ppi.o
 
 ifdef CONFIG_ACPI
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 6a973b9..3ec04f4 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -142,6 +142,7 @@ struct tpm_vendor_specific {
 
 	int region_size;
 	int have_region;
+	bool itpm;
 
 	struct list_head list;
 	int locality;
@@ -149,6 +150,7 @@ struct tpm_vendor_specific {
 	bool timeout_adjusted;
 	unsigned long duration[3]; /* jiffies */
 	bool duration_adjusted;
+	bool irq_tested;
 	void *priv;
 
 	wait_queue_head_t read_queue;
diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
index 607fa3f..eb86667 100644
--- a/drivers/char/tpm/tpm_tis.c
+++ b/drivers/char/tpm/tpm_tis.c
@@ -19,6 +19,7 @@
  * published by the Free Software Foundation, version 2 of the
  * License.
  */
+
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
@@ -29,40 +30,49 @@
 #include <linux/acpi.h>
 #include <linux/freezer.h>
 #include "tpm.h"
+#include "tpm_tis_core.h"
 
-enum tis_access {
-	TPM_ACCESS_VALID = 0x80,
-	TPM_ACCESS_ACTIVE_LOCALITY = 0x20,
-	TPM_ACCESS_REQUEST_PENDING = 0x04,
-	TPM_ACCESS_REQUEST_USE = 0x02,
-};
+static int read_mem_bytes(struct tpm_chip *chip, u32 addr, size_t len, u8 size,
+			  u8 *result)
+{
+	int i;
 
-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,
-};
+	switch (size) {
+	case 4:
+		*(u32 *)result = ioread32(chip->vendor.iobase + addr);
+	break;
+	case 2:
+		*(u16 *)result = ioread16(chip->vendor.iobase + addr);
+	break;
+	case 1:
+	default:
+		for (i = 0; i < len; i++)
+			result[i] = ioread8(chip->vendor.iobase + addr);
+	}
 
-enum tis_int_flags {
-	TPM_GLOBAL_INT_ENABLE = 0x80000000,
-	TPM_INTF_BURST_COUNT_STATIC = 0x100,
-	TPM_INTF_CMD_READY_INT = 0x080,
-	TPM_INTF_INT_EDGE_FALLING = 0x040,
-	TPM_INTF_INT_EDGE_RISING = 0x020,
-	TPM_INTF_INT_LEVEL_LOW = 0x010,
-	TPM_INTF_INT_LEVEL_HIGH = 0x008,
-	TPM_INTF_LOCALITY_CHANGE_INT = 0x004,
-	TPM_INTF_STS_VALID_INT = 0x002,
-	TPM_INTF_DATA_AVAIL_INT = 0x001,
-};
+	return 0;
+}
 
-enum tis_defaults {
-	TIS_MEM_LEN = 0x5000,
-	TIS_SHORT_TIMEOUT = 750,	/* ms */
-	TIS_LONG_TIMEOUT = 2000,	/* 2 sec */
-};
+static int write_mem_bytes(struct tpm_chip *chip, u32 addr, size_t len, u8 size,
+			   u8 *value)
+{
+	int i;
+
+	switch (size) {
+	case 4:
+		iowrite32(*(u32 *)value, chip->vendor.iobase + addr);
+	break;
+	case 2:
+		iowrite16(*(u16 *)value, chip->vendor.iobase + addr);
+	break;
+	case 1:
+	default:
+		for (i = 0 ; i < len; i++)
+			iowrite8(value[i], chip->vendor.iobase + addr);
+	}
+
+	return 0;
+}
 
 struct tpm_info {
 	struct resource res;
@@ -73,38 +83,14 @@ struct tpm_info {
 	int irq;
 };
 
-/* Some timeout values are needed before it is known whether the chip is
- * TPM 1.0 or TPM 2.0.
- */
-#define TIS_TIMEOUT_A_MAX	max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_A)
-#define TIS_TIMEOUT_B_MAX	max(TIS_LONG_TIMEOUT, TPM2_TIMEOUT_B)
-#define TIS_TIMEOUT_C_MAX	max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_C)
-#define TIS_TIMEOUT_D_MAX	max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_D)
-
-#define	TPM_ACCESS(l)			(0x0000 | ((l) << 12))
-#define	TPM_INT_ENABLE(l)		(0x0008 | ((l) << 12))
-#define	TPM_INT_VECTOR(l)		(0x000C | ((l) << 12))
-#define	TPM_INT_STATUS(l)		(0x0010 | ((l) << 12))
-#define	TPM_INTF_CAPS(l)		(0x0014 | ((l) << 12))
-#define	TPM_STS(l)			(0x0018 | ((l) << 12))
-#define	TPM_STS3(l)			(0x001b | ((l) << 12))
-#define	TPM_DATA_FIFO(l)		(0x0024 | ((l) << 12))
-
-#define	TPM_DID_VID(l)			(0x0F00 | ((l) << 12))
-#define	TPM_RID(l)			(0x0F04 | ((l) << 12))
-
-struct priv_data {
-	bool irq_tested;
-};
-
 #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
 static int has_hid(struct acpi_device *dev, const char *hid)
 {
 	struct acpi_hardware_id *id;
 
 	list_for_each_entry(id, &dev->pnp.ids, list)
-		if (!strcmp(hid, id->id))
-			return 1;
+	if (!strcmp(hid, id->id))
+		return 1;
 
 	return 0;
 }
@@ -120,409 +106,10 @@ static inline int is_itpm(struct acpi_device *dev)
 }
 #endif
 
-/* Before we attempt to access the TPM we must see that the valid bit is set.
- * The specification says that this bit is 0 at reset and remains 0 until the
- * 'TPM has gone through its self test and initialization and has established
- * correct values in the other bits.' */
-static int wait_startup(struct tpm_chip *chip, int l)
-{
-	unsigned long stop = jiffies + chip->vendor.timeout_a;
-	do {
-		if (ioread8(chip->vendor.iobase + TPM_ACCESS(l)) &
-		    TPM_ACCESS_VALID)
-			return 0;
-		msleep(TPM_TIMEOUT);
-	} while (time_before(jiffies, stop));
-	return -1;
-}
-
-static int check_locality(struct tpm_chip *chip, int l)
-{
-	if ((ioread8(chip->vendor.iobase + TPM_ACCESS(l)) &
-	     (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
-	    (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
-		return chip->vendor.locality = l;
-
-	return -1;
-}
-
-static void release_locality(struct tpm_chip *chip, int l, int force)
-{
-	if (force || (ioread8(chip->vendor.iobase + TPM_ACCESS(l)) &
-		      (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) ==
-	    (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID))
-		iowrite8(TPM_ACCESS_ACTIVE_LOCALITY,
-			 chip->vendor.iobase + TPM_ACCESS(l));
-}
-
-static int request_locality(struct tpm_chip *chip, int l)
-{
-	unsigned long stop, timeout;
-	long rc;
-
-	if (check_locality(chip, l) >= 0)
-		return l;
-
-	iowrite8(TPM_ACCESS_REQUEST_USE,
-		 chip->vendor.iobase + TPM_ACCESS(l));
-
-	stop = jiffies + chip->vendor.timeout_a;
-
-	if (chip->vendor.irq) {
-again:
-		timeout = stop - jiffies;
-		if ((long)timeout <= 0)
-			return -1;
-		rc = wait_event_interruptible_timeout(chip->vendor.int_queue,
-						      (check_locality
-						       (chip, l) >= 0),
-						      timeout);
-		if (rc > 0)
-			return l;
-		if (rc == -ERESTARTSYS && freezing(current)) {
-			clear_thread_flag(TIF_SIGPENDING);
-			goto again;
-		}
-	} else {
-		/* wait for burstcount */
-		do {
-			if (check_locality(chip, l) >= 0)
-				return l;
-			msleep(TPM_TIMEOUT);
-		}
-		while (time_before(jiffies, stop));
-	}
-	return -1;
-}
-
-static u8 tpm_tis_status(struct tpm_chip *chip)
-{
-	return ioread8(chip->vendor.iobase +
-		       TPM_STS(chip->vendor.locality));
-}
-
-static void tpm_tis_ready(struct tpm_chip *chip)
-{
-	/* this causes the current command to be aborted */
-	iowrite8(TPM_STS_COMMAND_READY,
-		 chip->vendor.iobase + TPM_STS(chip->vendor.locality));
-}
-
-static int get_burstcount(struct tpm_chip *chip)
-{
-	unsigned long stop;
-	int burstcnt;
-
-	/* wait for burstcount */
-	/* which timeout value, spec has 2 answers (c & d) */
-	stop = jiffies + chip->vendor.timeout_d;
-	do {
-		burstcnt = ioread8(chip->vendor.iobase +
-				   TPM_STS(chip->vendor.locality) + 1);
-		burstcnt += ioread8(chip->vendor.iobase +
-				    TPM_STS(chip->vendor.locality) +
-				    2) << 8;
-		if (burstcnt)
-			return burstcnt;
-		msleep(TPM_TIMEOUT);
-	} while (time_before(jiffies, stop));
-	return -EBUSY;
-}
-
-static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
-{
-	int size = 0, burstcnt;
-	while (size < count &&
-	       wait_for_tpm_stat(chip,
-				 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
-				 chip->vendor.timeout_c,
-				 &chip->vendor.read_queue, true)
-	       == 0) {
-		burstcnt = get_burstcount(chip);
-		for (; burstcnt > 0 && size < count; burstcnt--)
-			buf[size++] = ioread8(chip->vendor.iobase +
-					      TPM_DATA_FIFO(chip->vendor.
-							    locality));
-	}
-	return size;
-}
-
-static int tpm_tis_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 */
-	if ((size =
-	     recv_data(chip, buf, TPM_HEADER_SIZE)) < TPM_HEADER_SIZE) {
-		dev_err(&chip->dev, "Unable to read header\n");
-		goto out;
-	}
-
-	expected = be32_to_cpu(*(__be32 *) (buf + 2));
-	if (expected > count) {
-		size = -EIO;
-		goto out;
-	}
-
-	if ((size +=
-	     recv_data(chip, &buf[TPM_HEADER_SIZE],
-		       expected - TPM_HEADER_SIZE)) < expected) {
-		dev_err(&chip->dev, "Unable to read remainder of result\n");
-		size = -ETIME;
-		goto out;
-	}
-
-	wait_for_tpm_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c,
-			  &chip->vendor.int_queue, false);
-	status = tpm_tis_status(chip);
-	if (status & TPM_STS_DATA_AVAIL) {	/* retry? */
-		dev_err(&chip->dev, "Error left over data\n");
-		size = -EIO;
-		goto out;
-	}
-
-out:
-	tpm_tis_ready(chip);
-	release_locality(chip, chip->vendor.locality, 0);
-	return size;
-}
-
 static bool itpm;
 module_param(itpm, bool, 0444);
 MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)");
 
-/*
- * If interrupts are used (signaled by an irq set in the vendor structure)
- * tpm.c can skip polling for the data to be available as the interrupt is
- * waited for here
- */
-static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len)
-{
-	int rc, status, burstcnt;
-	size_t count = 0;
-
-	if (request_locality(chip, 0) < 0)
-		return -EBUSY;
-
-	status = tpm_tis_status(chip);
-	if ((status & TPM_STS_COMMAND_READY) == 0) {
-		tpm_tis_ready(chip);
-		if (wait_for_tpm_stat
-		    (chip, TPM_STS_COMMAND_READY, chip->vendor.timeout_b,
-		     &chip->vendor.int_queue, false) < 0) {
-			rc = -ETIME;
-			goto out_err;
-		}
-	}
-
-	while (count < len - 1) {
-		burstcnt = get_burstcount(chip);
-		for (; burstcnt > 0 && count < len - 1; burstcnt--) {
-			iowrite8(buf[count], chip->vendor.iobase +
-				 TPM_DATA_FIFO(chip->vendor.locality));
-			count++;
-		}
-
-		wait_for_tpm_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c,
-				  &chip->vendor.int_queue, false);
-		status = tpm_tis_status(chip);
-		if (!itpm && (status & TPM_STS_DATA_EXPECT) == 0) {
-			rc = -EIO;
-			goto out_err;
-		}
-	}
-
-	/* write last byte */
-	iowrite8(buf[count],
-		 chip->vendor.iobase + TPM_DATA_FIFO(chip->vendor.locality));
-	wait_for_tpm_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c,
-			  &chip->vendor.int_queue, false);
-	status = tpm_tis_status(chip);
-	if ((status & TPM_STS_DATA_EXPECT) != 0) {
-		rc = -EIO;
-		goto out_err;
-	}
-
-	return 0;
-
-out_err:
-	tpm_tis_ready(chip);
-	release_locality(chip, chip->vendor.locality, 0);
-	return rc;
-}
-
-static void disable_interrupts(struct tpm_chip *chip)
-{
-	u32 intmask;
-
-	intmask =
-	    ioread32(chip->vendor.iobase +
-		     TPM_INT_ENABLE(chip->vendor.locality));
-	intmask &= ~TPM_GLOBAL_INT_ENABLE;
-	iowrite32(intmask,
-		  chip->vendor.iobase +
-		  TPM_INT_ENABLE(chip->vendor.locality));
-	devm_free_irq(&chip->dev, chip->vendor.irq, chip);
-	chip->vendor.irq = 0;
-}
-
-/*
- * If interrupts are used (signaled by an irq set in the vendor structure)
- * tpm.c can skip polling for the data to be available as the interrupt is
- * waited for here
- */
-static int tpm_tis_send_main(struct tpm_chip *chip, u8 *buf, size_t len)
-{
-	int rc;
-	u32 ordinal;
-	unsigned long dur;
-
-	rc = tpm_tis_send_data(chip, buf, len);
-	if (rc < 0)
-		return rc;
-
-	/* go and do it */
-	iowrite8(TPM_STS_GO,
-		 chip->vendor.iobase + TPM_STS(chip->vendor.locality));
-
-	if (chip->vendor.irq) {
-		ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
-
-		if (chip->flags & TPM_CHIP_FLAG_TPM2)
-			dur = tpm2_calc_ordinal_duration(chip, ordinal);
-		else
-			dur = tpm_calc_ordinal_duration(chip, ordinal);
-
-		if (wait_for_tpm_stat
-		    (chip, TPM_STS_DATA_AVAIL | TPM_STS_VALID, dur,
-		     &chip->vendor.read_queue, false) < 0) {
-			rc = -ETIME;
-			goto out_err;
-		}
-	}
-	return len;
-out_err:
-	tpm_tis_ready(chip);
-	release_locality(chip, chip->vendor.locality, 0);
-	return rc;
-}
-
-static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
-{
-	int rc, irq;
-	struct priv_data *priv = chip->vendor.priv;
-
-	if (!chip->vendor.irq || priv->irq_tested)
-		return tpm_tis_send_main(chip, buf, len);
-
-	/* Verify receipt of the expected IRQ */
-	irq = chip->vendor.irq;
-	chip->vendor.irq = 0;
-	rc = tpm_tis_send_main(chip, buf, len);
-	chip->vendor.irq = irq;
-	if (!priv->irq_tested)
-		msleep(1);
-	if (!priv->irq_tested)
-		disable_interrupts(chip);
-	priv->irq_tested = true;
-	return rc;
-}
-
-struct tis_vendor_timeout_override {
-	u32 did_vid;
-	unsigned long timeout_us[4];
-};
-
-static const struct tis_vendor_timeout_override vendor_timeout_overrides[] = {
-	/* Atmel 3204 */
-	{ 0x32041114, { (TIS_SHORT_TIMEOUT*1000), (TIS_LONG_TIMEOUT*1000),
-			(TIS_SHORT_TIMEOUT*1000), (TIS_SHORT_TIMEOUT*1000) } },
-};
-
-static bool tpm_tis_update_timeouts(struct tpm_chip *chip,
-				    unsigned long *timeout_cap)
-{
-	int i;
-	u32 did_vid;
-
-	did_vid = ioread32(chip->vendor.iobase + TPM_DID_VID(0));
-
-	for (i = 0; i != ARRAY_SIZE(vendor_timeout_overrides); i++) {
-		if (vendor_timeout_overrides[i].did_vid != did_vid)
-			continue;
-		memcpy(timeout_cap, vendor_timeout_overrides[i].timeout_us,
-		       sizeof(vendor_timeout_overrides[i].timeout_us));
-		return true;
-	}
-
-	return false;
-}
-
-/*
- * Early probing for iTPM with STS_DATA_EXPECT flaw.
- * Try sending command without itpm flag set and if that
- * fails, repeat with itpm flag set.
- */
-static int probe_itpm(struct tpm_chip *chip)
-{
-	int rc = 0;
-	u8 cmd_getticks[] = {
-		0x00, 0xc1, 0x00, 0x00, 0x00, 0x0a,
-		0x00, 0x00, 0x00, 0xf1
-	};
-	size_t len = sizeof(cmd_getticks);
-	bool rem_itpm = itpm;
-	u16 vendor = ioread16(chip->vendor.iobase + TPM_DID_VID(0));
-
-	/* probe only iTPMS */
-	if (vendor != TPM_VID_INTEL)
-		return 0;
-
-	itpm = false;
-
-	rc = tpm_tis_send_data(chip, cmd_getticks, len);
-	if (rc == 0)
-		goto out;
-
-	tpm_tis_ready(chip);
-	release_locality(chip, chip->vendor.locality, 0);
-
-	itpm = true;
-
-	rc = tpm_tis_send_data(chip, cmd_getticks, len);
-	if (rc == 0) {
-		dev_info(&chip->dev, "Detected an iTPM.\n");
-		rc = 1;
-	} else
-		rc = -EFAULT;
-
-out:
-	itpm = rem_itpm;
-	tpm_tis_ready(chip);
-	release_locality(chip, chip->vendor.locality, 0);
-
-	return rc;
-}
-
-static bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status)
-{
-	switch (chip->vendor.manufacturer_id) {
-	case TPM_VID_WINBOND:
-		return ((status == TPM_STS_VALID) ||
-			(status == (TPM_STS_VALID | TPM_STS_COMMAND_READY)));
-	case TPM_VID_STM:
-		return (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY));
-	default:
-		return (status == TPM_STS_COMMAND_READY);
-	}
-}
-
 static const struct tpm_class_ops tpm_tis = {
 	.status = tpm_tis_status,
 	.recv = tpm_tis_recv,
@@ -532,153 +119,24 @@ static const struct tpm_class_ops tpm_tis = {
 	.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 	.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 	.req_canceled = tpm_tis_req_canceled,
+	.read_bytes = read_mem_bytes,
+	.write_bytes = write_mem_bytes,
 };
 
-static irqreturn_t tis_int_handler(int dummy, void *dev_id)
-{
-	struct tpm_chip *chip = dev_id;
-	u32 interrupt;
-	int i;
-
-	interrupt = ioread32(chip->vendor.iobase +
-			     TPM_INT_STATUS(chip->vendor.locality));
-
-	if (interrupt == 0)
-		return IRQ_NONE;
-
-	((struct priv_data *)chip->vendor.priv)->irq_tested = true;
-	if (interrupt & TPM_INTF_DATA_AVAIL_INT)
-		wake_up_interruptible(&chip->vendor.read_queue);
-	if (interrupt & TPM_INTF_LOCALITY_CHANGE_INT)
-		for (i = 0; i < 5; i++)
-			if (check_locality(chip, i) >= 0)
-				break;
-	if (interrupt &
-	    (TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_STS_VALID_INT |
-	     TPM_INTF_CMD_READY_INT))
-		wake_up_interruptible(&chip->vendor.int_queue);
-
-	/* Clear interrupts handled with TPM_EOI */
-	iowrite32(interrupt,
-		  chip->vendor.iobase +
-		  TPM_INT_STATUS(chip->vendor.locality));
-	ioread32(chip->vendor.iobase + TPM_INT_STATUS(chip->vendor.locality));
-	return IRQ_HANDLED;
-}
-
-/* Register the IRQ and issue a command that will cause an interrupt. If an
- * irq is seen then leave the chip setup for IRQ operation, otherwise reverse
- * everything and leave in polling mode. Returns 0 on success.
- */
-static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
-				    int flags, int irq)
-{
-	struct priv_data *priv = chip->vendor.priv;
-	u8 original_int_vec;
-
-	if (devm_request_irq(&chip->dev, irq, tis_int_handler, flags,
-			     dev_name(&chip->dev), chip) != 0) {
-		dev_info(&chip->dev, "Unable to request irq: %d for probe\n",
-			 irq);
-		return -1;
-	}
-	chip->vendor.irq = irq;
-
-	original_int_vec = ioread8(chip->vendor.iobase +
-				   TPM_INT_VECTOR(chip->vendor.locality));
-	iowrite8(irq,
-		 chip->vendor.iobase + TPM_INT_VECTOR(chip->vendor.locality));
-
-	/* Clear all existing */
-	iowrite32(ioread32(chip->vendor.iobase +
-			   TPM_INT_STATUS(chip->vendor.locality)),
-		  chip->vendor.iobase + TPM_INT_STATUS(chip->vendor.locality));
-
-	/* Turn on */
-	iowrite32(intmask | TPM_GLOBAL_INT_ENABLE,
-		  chip->vendor.iobase + TPM_INT_ENABLE(chip->vendor.locality));
-
-	priv->irq_tested = false;
-
-	/* Generate an interrupt by having the core call through to
-	 * tpm_tis_send
-	 */
-	if (chip->flags & TPM_CHIP_FLAG_TPM2)
-		tpm2_gen_interrupt(chip);
-	else
-		tpm_gen_interrupt(chip);
-
-	/* tpm_tis_send will either confirm the interrupt is working or it
-	 * will call disable_irq which undoes all of the above.
-	 */
-	if (!chip->vendor.irq) {
-		iowrite8(original_int_vec,
-			 chip->vendor.iobase +
-			     TPM_INT_VECTOR(chip->vendor.locality));
-		return 1;
-	}
-
-	return 0;
-}
-
-/* Try to find the IRQ the TPM is using. This is for legacy x86 systems that
- * do not have ACPI/etc. We typically expect the interrupt to be declared if
- * present.
- */
-static void tpm_tis_probe_irq(struct tpm_chip *chip, u32 intmask)
-{
-	u8 original_int_vec;
-	int i;
-
-	original_int_vec = ioread8(chip->vendor.iobase +
-				   TPM_INT_VECTOR(chip->vendor.locality));
-
-	if (!original_int_vec) {
-		if (IS_ENABLED(CONFIG_X86))
-			for (i = 3; i <= 15; i++)
-				if (!tpm_tis_probe_irq_single(chip, intmask, 0,
-							      i))
-					return;
-	} else if (!tpm_tis_probe_irq_single(chip, intmask, 0,
-					     original_int_vec))
-		return;
-}
-
 static bool interrupts = true;
 module_param(interrupts, bool, 0444);
 MODULE_PARM_DESC(interrupts, "Enable interrupts");
 
-static void tpm_tis_remove(struct tpm_chip *chip)
-{
-	if (chip->flags & TPM_CHIP_FLAG_TPM2)
-		tpm2_shutdown(chip, TPM2_SU_CLEAR);
-
-	iowrite32(~TPM_GLOBAL_INT_ENABLE &
-		  ioread32(chip->vendor.iobase +
-			   TPM_INT_ENABLE(chip->vendor.
-					  locality)),
-		  chip->vendor.iobase +
-		  TPM_INT_ENABLE(chip->vendor.locality));
-	release_locality(chip, chip->vendor.locality, 1);
-}
-
 static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info,
 			acpi_handle acpi_dev_handle)
 {
-	u32 vendor, intfcaps, intmask;
-	int rc, probe;
+	int ret, irq = tpm_info->irq;
 	struct tpm_chip *chip;
-	struct priv_data *priv;
-
-	priv = devm_kzalloc(dev, sizeof(struct priv_data), GFP_KERNEL);
-	if (priv == NULL)
-		return -ENOMEM;
 
 	chip = tpmm_chip_alloc(dev, &tpm_tis);
 	if (IS_ERR(chip))
 		return PTR_ERR(chip);
 
-	tpm_set_vendordata(chip, priv);
 #ifdef CONFIG_ACPI
 	chip->acpi_dev_handle = acpi_dev_handle;
 #endif
@@ -687,177 +145,22 @@ static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info,
 	if (IS_ERR(chip->vendor.iobase))
 		return PTR_ERR(chip->vendor.iobase);
 
-	/* Maximum timeouts */
-	chip->vendor.timeout_a = TIS_TIMEOUT_A_MAX;
-	chip->vendor.timeout_b = TIS_TIMEOUT_B_MAX;
-	chip->vendor.timeout_c = TIS_TIMEOUT_C_MAX;
-	chip->vendor.timeout_d = TIS_TIMEOUT_D_MAX;
-
-	if (wait_startup(chip, 0) != 0) {
-		rc = -ENODEV;
-		goto out_err;
-	}
+	chip->vendor.itpm = itpm;
 
-	/* Take control of the TPM's interrupt hardware and shut it off */
-	intmask = ioread32(chip->vendor.iobase +
-			   TPM_INT_ENABLE(chip->vendor.locality));
-	intmask |= TPM_INTF_CMD_READY_INT | TPM_INTF_LOCALITY_CHANGE_INT |
-		   TPM_INTF_DATA_AVAIL_INT | TPM_INTF_STS_VALID_INT;
-	intmask &= ~TPM_GLOBAL_INT_ENABLE;
-	iowrite32(intmask,
-		  chip->vendor.iobase + TPM_INT_ENABLE(chip->vendor.locality));
-
-	if (request_locality(chip, 0) != 0) {
-		rc = -ENODEV;
-		goto out_err;
-	}
+	if (!interrupts)
+		irq = -1;
 
-	rc = tpm2_probe(chip);
-	if (rc)
+	ret = tpm_tis_init_core(dev, chip, irq, IRQF_SHARED);
+	if (ret < 0)
 		goto out_err;
 
-	vendor = ioread32(chip->vendor.iobase + TPM_DID_VID(0));
-	chip->vendor.manufacturer_id = vendor;
-
-	dev_info(dev, "%s TPM (device-id 0x%X, rev-id %d)\n",
-		 (chip->flags & TPM_CHIP_FLAG_TPM2) ? "2.0" : "1.2",
-		 vendor >> 16, ioread8(chip->vendor.iobase + TPM_RID(0)));
-
-	if (!itpm) {
-		probe = probe_itpm(chip);
-		if (probe < 0) {
-			rc = -ENODEV;
-			goto out_err;
-		}
-		itpm = !!probe;
-	}
-
-	if (itpm)
-		dev_info(dev, "Intel iTPM workaround enabled\n");
-
-
-	/* Figure out the capabilities */
-	intfcaps =
-	    ioread32(chip->vendor.iobase +
-		     TPM_INTF_CAPS(chip->vendor.locality));
-	dev_dbg(dev, "TPM interface capabilities (0x%x):\n",
-		intfcaps);
-	if (intfcaps & TPM_INTF_BURST_COUNT_STATIC)
-		dev_dbg(dev, "\tBurst Count Static\n");
-	if (intfcaps & TPM_INTF_CMD_READY_INT)
-		dev_dbg(dev, "\tCommand Ready Int Support\n");
-	if (intfcaps & TPM_INTF_INT_EDGE_FALLING)
-		dev_dbg(dev, "\tInterrupt Edge Falling\n");
-	if (intfcaps & TPM_INTF_INT_EDGE_RISING)
-		dev_dbg(dev, "\tInterrupt Edge Rising\n");
-	if (intfcaps & TPM_INTF_INT_LEVEL_LOW)
-		dev_dbg(dev, "\tInterrupt Level Low\n");
-	if (intfcaps & TPM_INTF_INT_LEVEL_HIGH)
-		dev_dbg(dev, "\tInterrupt Level High\n");
-	if (intfcaps & TPM_INTF_LOCALITY_CHANGE_INT)
-		dev_dbg(dev, "\tLocality Change Int Support\n");
-	if (intfcaps & TPM_INTF_STS_VALID_INT)
-		dev_dbg(dev, "\tSts Valid Int Support\n");
-	if (intfcaps & TPM_INTF_DATA_AVAIL_INT)
-		dev_dbg(dev, "\tData Avail Int Support\n");
-
-	/* Very early on issue a command to the TPM in polling mode to make
-	 * sure it works. May as well use that command to set the proper
-	 *  timeouts for the driver.
-	 */
-	if (tpm_get_timeouts(chip)) {
-		dev_err(dev, "Could not get TPM timeouts and durations\n");
-		rc = -ENODEV;
-		goto out_err;
-	}
+	return ret;
 
-	/* INTERRUPT Setup */
-	init_waitqueue_head(&chip->vendor.read_queue);
-	init_waitqueue_head(&chip->vendor.int_queue);
-	if (interrupts && tpm_info->irq != -1) {
-		if (tpm_info->irq) {
-			tpm_tis_probe_irq_single(chip, intmask, IRQF_SHARED,
-						 tpm_info->irq);
-			if (!chip->vendor.irq)
-				dev_err(&chip->dev, FW_BUG
-					"TPM interrupt not working, polling instead\n");
-		} else
-			tpm_tis_probe_irq(chip, intmask);
-	}
-
-	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
-		rc = tpm2_do_selftest(chip);
-		if (rc == TPM2_RC_INITIALIZE) {
-			dev_warn(dev, "Firmware has not started TPM\n");
-			rc  = tpm2_startup(chip, TPM2_SU_CLEAR);
-			if (!rc)
-				rc = tpm2_do_selftest(chip);
-		}
-
-		if (rc) {
-			dev_err(dev, "TPM self test failed\n");
-			if (rc > 0)
-				rc = -ENODEV;
-			goto out_err;
-		}
-	} else {
-		if (tpm_do_selftest(chip)) {
-			dev_err(dev, "TPM self test failed\n");
-			rc = -ENODEV;
-			goto out_err;
-		}
-	}
-
-	return tpm_chip_register(chip);
 out_err:
 	tpm_tis_remove(chip);
-	return rc;
-}
-
-#ifdef CONFIG_PM_SLEEP
-static void tpm_tis_reenable_interrupts(struct tpm_chip *chip)
-{
-	u32 intmask;
-
-	/* reenable interrupts that device may have lost or
-	   BIOS/firmware may have disabled */
-	iowrite8(chip->vendor.irq, chip->vendor.iobase +
-		 TPM_INT_VECTOR(chip->vendor.locality));
-
-	intmask =
-	    ioread32(chip->vendor.iobase +
-		     TPM_INT_ENABLE(chip->vendor.locality));
-
-	intmask |= TPM_INTF_CMD_READY_INT
-	    | TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_DATA_AVAIL_INT
-	    | TPM_INTF_STS_VALID_INT | TPM_GLOBAL_INT_ENABLE;
-
-	iowrite32(intmask,
-		  chip->vendor.iobase + TPM_INT_ENABLE(chip->vendor.locality));
+	return ret;
 }
 
-static int tpm_tis_resume(struct device *dev)
-{
-	struct tpm_chip *chip = dev_get_drvdata(dev);
-	int ret;
-
-	if (chip->vendor.irq)
-		tpm_tis_reenable_interrupts(chip);
-
-	ret = tpm_pm_resume(dev);
-	if (ret)
-		return ret;
-
-	/* TPM 1.2 requires self-test on resume. This function actually returns
-	 * an error code but for unknown reason it isn't handled.
-	 */
-	if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
-		tpm_do_selftest(chip);
-
-	return 0;
-}
-#endif
-
 static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
 
 static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
@@ -919,7 +222,7 @@ static struct pnp_driver tis_pnp_driver = {
 	},
 };
 
-#define TIS_HID_USR_IDX sizeof(tpm_pnp_tbl)/sizeof(struct pnp_device_id) -2
+#define TIS_HID_USR_IDX (sizeof(tpm_pnp_tbl) / sizeof(struct pnp_device_id) - 2)
 module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,
 		    sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);
 MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
new file mode 100644
index 0000000..b9cc61f
--- /dev/null
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -0,0 +1,728 @@
+/*
+ * Copyright (C) 2005, 2006 IBM Corporation
+ * Copyright (C) 2014, 2015 Intel Corporation
+ *
+ * Authors:
+ * Leendert van Doorn <leendert@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 device driver implements the TPM interface as defined in
+ * the TCG TPM Interface Spec version 1.2, revision 1.0.
+ *
+ * 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.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/pnp.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/wait.h>
+#include <linux/acpi.h>
+#include <linux/freezer.h>
+#include "tpm.h"
+#include "tpm_tis_core.h"
+
+struct tpm_info {
+	struct resource res;
+	/* irq > 0 means: use irq $irq;
+	 * irq = 0 means: autoprobe for an irq;
+	 * irq = -1 means: no irq support
+	 */
+	int irq;
+};
+
+/* Before we attempt to access the TPM we must see that the valid bit is set.
+ * The specification says that this bit is 0 at reset and remains 0 until the
+ * 'TPM has gone through its self test and initialization and has established
+ * correct values in the other bits.'
+ */
+static int wait_startup(struct tpm_chip *chip, int l)
+{
+	unsigned long stop = jiffies + chip->vendor.timeout_a;
+
+	do {
+		if (tpm_read_byte(chip, TPM_ACCESS(l)) & TPM_ACCESS_VALID)
+			return 0;
+		msleep(TPM_TIMEOUT);
+	} while (time_before(jiffies, stop));
+	return -1;
+}
+
+static int check_locality(struct tpm_chip *chip, int l)
+{
+	if ((tpm_read_byte(chip, TPM_ACCESS(l)) &
+	     (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
+	    (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
+		return chip->vendor.locality = l;
+
+	return -1;
+}
+
+static void release_locality(struct tpm_chip *chip, int l, int force)
+{
+	if (force || (tpm_read_byte(chip, TPM_ACCESS(l)) &
+		      (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) ==
+	    (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID))
+		tpm_write_byte(chip, TPM_ACCESS(l), TPM_ACCESS_ACTIVE_LOCALITY);
+}
+
+static int request_locality(struct tpm_chip *chip, int l)
+{
+	unsigned long stop, timeout;
+	long rc;
+
+	if (check_locality(chip, l) >= 0)
+		return l;
+
+	tpm_write_byte(chip, TPM_ACCESS(l), TPM_ACCESS_REQUEST_USE);
+
+	stop = jiffies + chip->vendor.timeout_a;
+
+	if (chip->vendor.irq) {
+again:
+		timeout = stop - jiffies;
+		if ((long)timeout <= 0)
+			return -1;
+		rc = wait_event_interruptible_timeout(chip->vendor.int_queue,
+						      (check_locality
+						       (chip, l) >= 0),
+						      timeout);
+		if (rc > 0)
+			return l;
+		if (rc == -ERESTARTSYS && freezing(current)) {
+			clear_thread_flag(TIF_SIGPENDING);
+			goto again;
+		}
+	} else {
+		/* wait for burstcount */
+		do {
+			if (check_locality(chip, l) >= 0)
+				return l;
+			msleep(TPM_TIMEOUT);
+		} while (time_before(jiffies, stop));
+	}
+	return -1;
+}
+
+u8 tpm_tis_status(struct tpm_chip *chip)
+{
+	return tpm_read_byte(chip, TPM_STS(chip->vendor.locality));
+}
+EXPORT_SYMBOL(tpm_tis_status);
+
+void tpm_tis_ready(struct tpm_chip *chip)
+{
+	/* this causes the current command to be aborted */
+	tpm_write_byte(chip, TPM_STS(chip->vendor.locality),
+		       TPM_STS_COMMAND_READY);
+}
+EXPORT_SYMBOL(tpm_tis_ready);
+
+static int get_burstcount(struct tpm_chip *chip)
+{
+	unsigned long stop;
+	int burstcnt, status;
+	u8 temp;
+
+	/* wait for burstcount */
+	/* which timeout value, spec has 2 answers (c & d) */
+	stop = jiffies + chip->vendor.timeout_d;
+	do {
+		status = tpm_read_bytes(chip, TPM_STS(chip->vendor.locality) +
+					1, 1, &temp);
+		if (status < 0)
+			return -EBUSY;
+
+		burstcnt = temp;
+		status = tpm_read_bytes(chip, TPM_STS(chip->vendor.locality) +
+					2, 1, &temp);
+		if (status < 0)
+			return -EBUSY;
+
+		burstcnt |= temp << 8;
+
+		if (burstcnt)
+			return burstcnt;
+		msleep(TPM_TIMEOUT);
+	} while (time_before(jiffies, stop));
+	return -EBUSY;
+}
+
+static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
+{
+	int size = 0, burstcnt, transfer_size, ret;
+
+	while (size < count &&
+		wait_for_tpm_stat(chip,
+				 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
+				 chip->vendor.timeout_c,
+				 &chip->vendor.read_queue, true) == 0) {
+		burstcnt = get_burstcount(chip);
+
+		transfer_size = min_t(size_t, (count - size), burstcnt);
+
+		ret = tpm_read_bytes(chip, TPM_DATA_FIFO(chip->vendor.locality),
+				     transfer_size, &buf[size]);
+		if (ret < 0)
+			return ret;
+
+		size += transfer_size;
+	}
+
+	return size;
+}
+
+int tpm_tis_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 = be32_to_cpu(*(__be32 *) (buf + 2));
+	if (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_tpm_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c,
+			  &chip->vendor.int_queue, false);
+	status = tpm_tis_status(chip);
+	if (status & TPM_STS_DATA_AVAIL) {	/* retry? */
+		dev_err(&chip->dev, "Error left over data\n");
+		size = -EIO;
+		goto out;
+	}
+
+out:
+	tpm_tis_ready(chip);
+	release_locality(chip, chip->vendor.locality, 0);
+	return size;
+}
+EXPORT_SYMBOL(tpm_tis_recv);
+
+/*
+ * If interrupts are used (signaled by an irq set in the vendor structure)
+ * tpm.c can skip polling for the data to be available as the interrupt is
+ * waited for here
+ */
+static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len)
+{
+	int rc, status, burstcnt, transfer_size;
+	size_t count = 0;
+
+	if (request_locality(chip, 0) < 0)
+		return -EBUSY;
+
+	status = tpm_tis_status(chip);
+	if ((status & TPM_STS_COMMAND_READY) == 0) {
+		tpm_tis_ready(chip);
+		if (wait_for_tpm_stat
+		    (chip, TPM_STS_COMMAND_READY, chip->vendor.timeout_b,
+		     &chip->vendor.int_queue, false) < 0) {
+			rc = -ETIME;
+			goto out_err;
+		}
+	}
+
+	while (count < len - 1) {
+		burstcnt = get_burstcount(chip);
+		transfer_size = min_t(size_t, len - count - 1, burstcnt);
+
+		rc = tpm_write_bytes(chip, TPM_DATA_FIFO(chip->vendor.locality),
+				     transfer_size, &buf[count]);
+		if (rc < 0)
+			goto out_err;
+
+		count += transfer_size;
+
+		wait_for_tpm_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c,
+				  &chip->vendor.int_queue, false);
+		status = tpm_tis_status(chip);
+		if (!chip->vendor.itpm && (status & TPM_STS_DATA_EXPECT) == 0) {
+			rc = -EIO;
+			goto out_err;
+		}
+	}
+
+	/* write last byte */
+	tpm_write_byte(chip, TPM_DATA_FIFO(chip->vendor.locality), buf[count]);
+	wait_for_tpm_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c,
+			  &chip->vendor.int_queue, false);
+	status = tpm_tis_status(chip);
+	if ((status & TPM_STS_DATA_EXPECT) != 0) {
+		rc = -EIO;
+		goto out_err;
+	}
+
+	return 0;
+
+out_err:
+	tpm_tis_ready(chip);
+	release_locality(chip, chip->vendor.locality, 0);
+	return rc;
+}
+
+static void disable_interrupts(struct tpm_chip *chip)
+{
+	u32 intmask;
+
+	intmask = tpm_read_dword(chip, TPM_INT_ENABLE(chip->vendor.locality));
+	intmask &= ~TPM_GLOBAL_INT_ENABLE;
+	tpm_write_dword(chip, TPM_INT_ENABLE(chip->vendor.locality), intmask);
+	devm_free_irq(&chip->dev, chip->vendor.irq, chip);
+	chip->vendor.irq = 0;
+}
+
+/*
+ * If interrupts are used (signaled by an irq set in the vendor structure)
+ * tpm.c can skip polling for the data to be available as the interrupt is
+ * waited for here
+ */
+static int tpm_tis_send_main(struct tpm_chip *chip, u8 *buf, size_t len)
+{
+	int rc;
+	u32 ordinal;
+	unsigned long dur;
+
+	rc = tpm_tis_send_data(chip, buf, len);
+	if (rc < 0)
+		return rc;
+
+	/* go and do it */
+	tpm_write_byte(chip, TPM_STS(chip->vendor.locality), TPM_STS_GO);
+
+	if (chip->vendor.irq) {
+		ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
+
+		if (chip->flags & TPM_CHIP_FLAG_TPM2)
+			dur = tpm2_calc_ordinal_duration(chip, ordinal);
+		else
+			dur = tpm_calc_ordinal_duration(chip, ordinal);
+
+		if (wait_for_tpm_stat
+		    (chip, TPM_STS_DATA_AVAIL | TPM_STS_VALID, dur,
+		     &chip->vendor.read_queue, false) < 0) {
+			rc = -ETIME;
+			goto out_err;
+		}
+	}
+	return len;
+out_err:
+	tpm_tis_ready(chip);
+	release_locality(chip, chip->vendor.locality, 0);
+	return rc;
+}
+
+int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
+{
+	int rc, irq;
+
+	if (!chip->vendor.irq || chip->vendor.irq_tested)
+		return tpm_tis_send_main(chip, buf, len);
+
+	/* Verify receipt of the expected IRQ */
+	irq = chip->vendor.irq;
+	chip->vendor.irq = 0;
+	rc = tpm_tis_send_main(chip, buf, len);
+	chip->vendor.irq = irq;
+	if (!chip->vendor.irq_tested)
+		msleep(1);
+	if (!chip->vendor.irq_tested)
+		disable_interrupts(chip);
+	chip->vendor.irq_tested = true;
+	return rc;
+}
+EXPORT_SYMBOL(tpm_tis_send);
+
+bool tpm_tis_update_timeouts(struct tpm_chip *chip, unsigned long *timeout_cap)
+{
+	int i;
+	u32 did_vid;
+
+	did_vid = tpm_read_dword(chip, TPM_DID_VID(0));
+
+	for (i = 0; i != ARRAY_SIZE(vendor_timeout_overrides); i++) {
+		if (vendor_timeout_overrides[i].did_vid != did_vid)
+			continue;
+		memcpy(timeout_cap, vendor_timeout_overrides[i].timeout_us,
+		       sizeof(vendor_timeout_overrides[i].timeout_us));
+		return true;
+	}
+
+	return false;
+}
+EXPORT_SYMBOL(tpm_tis_update_timeouts);
+
+/*
+ * Early probing for iTPM with STS_DATA_EXPECT flaw.
+ * Try sending command without itpm flag set and if that
+ * fails, repeat with itpm flag set.
+ */
+static int probe_itpm(struct tpm_chip *chip)
+{
+	int rc = 0;
+	u8 cmd_getticks[] = {
+		0x00, 0xc1, 0x00, 0x00, 0x00, 0x0a,
+		0x00, 0x00, 0x00, 0xf1
+	};
+	size_t len = sizeof(cmd_getticks);
+	bool rem_itpm = chip->vendor.itpm;
+	u16 vendor = tpm_read_word(chip, TPM_DID_VID(0));
+
+	/* probe only iTPMS */
+	if (vendor != TPM_VID_INTEL)
+		return 0;
+
+	chip->vendor.itpm = false;
+
+	rc = tpm_tis_send_data(chip, cmd_getticks, len);
+	if (rc == 0)
+		goto out;
+
+	tpm_tis_ready(chip);
+	release_locality(chip, chip->vendor.locality, 0);
+
+	chip->vendor.itpm = true;
+
+	rc = tpm_tis_send_data(chip, cmd_getticks, len);
+	if (rc == 0) {
+		dev_info(&chip->dev, "Detected an iTPM.\n");
+		rc = 1;
+	} else {
+		rc = -EFAULT;
+	}
+
+out:
+	chip->vendor.itpm = rem_itpm;
+	tpm_tis_ready(chip);
+	release_locality(chip, chip->vendor.locality, 0);
+
+	return rc;
+}
+
+bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status)
+{
+	switch (chip->vendor.manufacturer_id) {
+	case TPM_VID_WINBOND:
+		return ((status == TPM_STS_VALID) ||
+			(status == (TPM_STS_VALID | TPM_STS_COMMAND_READY)));
+	case TPM_VID_STM:
+		return (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY));
+	default:
+		return (status == TPM_STS_COMMAND_READY);
+	}
+}
+EXPORT_SYMBOL(tpm_tis_req_canceled);
+
+static irqreturn_t tis_int_handler(int dummy, void *dev_id)
+{
+	struct tpm_chip *chip = dev_id;
+	u32 interrupt;
+	int i;
+
+	interrupt = tpm_read_dword(chip, TPM_INT_STATUS(chip->vendor.locality));
+
+	if (interrupt == 0)
+		return IRQ_NONE;
+
+	chip->vendor.irq_tested = true;
+	if (interrupt & TPM_INTF_DATA_AVAIL_INT)
+		wake_up_interruptible(&chip->vendor.read_queue);
+	if (interrupt & TPM_INTF_LOCALITY_CHANGE_INT)
+		for (i = 0; i < 5; i++)
+			if (check_locality(chip, i) >= 0)
+				break;
+	if (interrupt &
+	    (TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_STS_VALID_INT |
+	     TPM_INTF_CMD_READY_INT))
+		wake_up_interruptible(&chip->vendor.int_queue);
+
+	/* Clear interrupts handled with TPM_EOI */
+	tpm_write_dword(chip, TPM_INT_STATUS(chip->vendor.locality), interrupt);
+	tpm_read_dword(chip, TPM_INT_STATUS(chip->vendor.locality));
+	return IRQ_HANDLED;
+}
+
+/* Register the IRQ and issue a command that will cause an interrupt. If an
+ * irq is seen then leave the chip setup for IRQ operation, otherwise reverse
+ * everything and leave in polling mode. Returns 0 on success.
+ */
+static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
+				    int flags, int irq)
+{
+	u8 original_int_vec;
+
+	if (devm_request_irq(&chip->dev, irq, tis_int_handler, flags,
+			     dev_name(&chip->dev), chip) != 0) {
+		dev_info(&chip->dev, "Unable to request irq: %d for probe\n",
+			 irq);
+		return -1;
+	}
+	chip->vendor.irq = irq;
+
+	original_int_vec = tpm_read_byte(chip, TPM_INT_VECTOR(chip->vendor.locality));
+	tpm_write_byte(chip, TPM_INT_VECTOR(chip->vendor.locality), irq);
+
+	/* Clear all existing */
+	tpm_write_dword(chip, TPM_INT_STATUS(chip->vendor.locality),
+			tpm_read_dword(chip, TPM_INT_STATUS(chip->vendor.locality)));
+
+	/* Turn on */
+	tpm_write_dword(chip, TPM_INT_ENABLE(chip->vendor.locality),
+			intmask | TPM_GLOBAL_INT_ENABLE);
+
+	chip->vendor.irq_tested = false;
+
+	/* Generate an interrupt by having the core call through to
+	 * tpm_tis_send
+	 */
+	if (chip->flags & TPM_CHIP_FLAG_TPM2)
+		tpm2_gen_interrupt(chip);
+	else
+		tpm_gen_interrupt(chip);
+
+	/* tpm_tis_send will either confirm the interrupt is working or it
+	 * will call disable_irq which undoes all of the above.
+	 */
+	if (!chip->vendor.irq) {
+		tpm_write_byte(chip, TPM_INT_VECTOR(chip->vendor.locality),
+			       original_int_vec);
+		return 1;
+	}
+
+	return 0;
+}
+
+/* Try to find the IRQ the TPM is using. This is for legacy x86 systems that
+ * do not have ACPI/etc. We typically expect the interrupt to be declared if
+ * present.
+ */
+static void tpm_tis_probe_irq(struct tpm_chip *chip, u32 intmask)
+{
+	u8 original_int_vec;
+	int i;
+
+	original_int_vec = tpm_read_byte(chip,
+					 TPM_INT_VECTOR(chip->vendor.locality));
+
+	if (!original_int_vec) {
+		if (IS_ENABLED(CONFIG_X86))
+			for (i = 3; i <= 15; i++)
+				if (!tpm_tis_probe_irq_single(chip, intmask, 0,
+							      i))
+					return;
+	} else if (!tpm_tis_probe_irq_single(chip, intmask, 0,
+					     original_int_vec))
+		return;
+}
+
+void tpm_tis_remove(struct tpm_chip *chip)
+{
+	if (chip->flags & TPM_CHIP_FLAG_TPM2)
+		tpm2_shutdown(chip, TPM2_SU_CLEAR);
+
+	tpm_write_dword(chip, TPM_INT_ENABLE(chip->vendor.locality),
+			~TPM_GLOBAL_INT_ENABLE &
+			tpm_read_dword(chip,
+				       TPM_INT_ENABLE(chip->vendor.locality)));
+	release_locality(chip, chip->vendor.locality, 1);
+}
+EXPORT_SYMBOL(tpm_tis_remove);
+
+int tpm_tis_init_core(struct device *dev, struct tpm_chip *chip,
+		      int irq, int irq_flags)
+{
+	u32 vendor, intfcaps, intmask;
+	int rc, probe;
+
+	/* Maximum timeouts */
+	chip->vendor.timeout_a = TIS_TIMEOUT_A_MAX;
+	chip->vendor.timeout_b = TIS_TIMEOUT_B_MAX;
+	chip->vendor.timeout_c = TIS_TIMEOUT_C_MAX;
+	chip->vendor.timeout_d = TIS_TIMEOUT_D_MAX;
+
+	if (wait_startup(chip, 0) != 0) {
+		rc = -ENODEV;
+		goto out_err;
+	}
+
+	/* Take control of the TPM's interrupt hardware and shut it off */
+	intmask = tpm_read_dword(chip, TPM_INT_ENABLE(chip->vendor.locality));
+	intmask |= TPM_INTF_CMD_READY_INT | TPM_INTF_LOCALITY_CHANGE_INT |
+		   TPM_INTF_DATA_AVAIL_INT | TPM_INTF_STS_VALID_INT;
+	intmask &= ~TPM_GLOBAL_INT_ENABLE;
+	tpm_write_dword(chip, TPM_INT_ENABLE(chip->vendor.locality), intmask);
+
+	if (request_locality(chip, 0) != 0) {
+		rc = -ENODEV;
+		goto out_err;
+	}
+
+	rc = tpm2_probe(chip);
+	if (rc)
+		goto out_err;
+
+	vendor = tpm_read_dword(chip, TPM_DID_VID(0));
+	chip->vendor.manufacturer_id = vendor;
+
+	dev_info(dev, "%s TPM (device-id 0x%X, rev-id %d)\n",
+		 (chip->flags & TPM_CHIP_FLAG_TPM2) ? "2.0" : "1.2",
+		 vendor >> 16, tpm_read_byte(chip, TPM_RID(0)));
+
+	if (!chip->vendor.itpm) {
+		probe = probe_itpm(chip);
+		if (probe < 0) {
+			rc = -ENODEV;
+			goto out_err;
+		}
+		chip->vendor.itpm = !!probe;
+	}
+
+	if (chip->vendor.itpm)
+		dev_info(dev, "Intel iTPM workaround enabled\n");
+
+	/* Figure out the capabilities */
+	intfcaps = tpm_read_dword(chip, TPM_INTF_CAPS(chip->vendor.locality));
+	dev_dbg(dev, "TPM interface capabilities (0x%x):\n", intfcaps);
+	if (intfcaps & TPM_INTF_BURST_COUNT_STATIC)
+		dev_dbg(dev, "\tBurst Count Static\n");
+	if (intfcaps & TPM_INTF_CMD_READY_INT)
+		dev_dbg(dev, "\tCommand Ready Int Support\n");
+	if (intfcaps & TPM_INTF_INT_EDGE_FALLING)
+		dev_dbg(dev, "\tInterrupt Edge Falling\n");
+	if (intfcaps & TPM_INTF_INT_EDGE_RISING)
+		dev_dbg(dev, "\tInterrupt Edge Rising\n");
+	if (intfcaps & TPM_INTF_INT_LEVEL_LOW)
+		dev_dbg(dev, "\tInterrupt Level Low\n");
+	if (intfcaps & TPM_INTF_INT_LEVEL_HIGH)
+		dev_dbg(dev, "\tInterrupt Level High\n");
+	if (intfcaps & TPM_INTF_LOCALITY_CHANGE_INT)
+		dev_dbg(dev, "\tLocality Change Int Support\n");
+	if (intfcaps & TPM_INTF_STS_VALID_INT)
+		dev_dbg(dev, "\tSts Valid Int Support\n");
+	if (intfcaps & TPM_INTF_DATA_AVAIL_INT)
+		dev_dbg(dev, "\tData Avail Int Support\n");
+
+	/* Very early on issue a command to the TPM in polling mode to make
+	 * sure it works. May as well use that command to set the proper
+	 *  timeouts for the driver.
+	 */
+	if (tpm_get_timeouts(chip)) {
+		dev_err(dev, "Could not get TPM timeouts and durations\n");
+		rc = -ENODEV;
+		goto out_err;
+	}
+
+	/* INTERRUPT Setup */
+	init_waitqueue_head(&chip->vendor.read_queue);
+	init_waitqueue_head(&chip->vendor.int_queue);
+	if (irq > 0) {
+		tpm_tis_probe_irq_single(chip, intmask, irq_flags, irq);
+		if (!chip->vendor.irq)
+			dev_err(&chip->dev, FW_BUG
+				"TPM interrupt not working, polling instead\n");
+	} else if (irq != -1) {
+		tpm_tis_probe_irq(chip, intmask);
+	}
+
+	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+		rc = tpm2_do_selftest(chip);
+		if (rc == TPM2_RC_INITIALIZE) {
+			dev_warn(dev, "Firmware has not started TPM\n");
+			rc  = tpm2_startup(chip, TPM2_SU_CLEAR);
+			if (!rc)
+				rc = tpm2_do_selftest(chip);
+		}
+
+		if (rc) {
+			dev_err(dev, "TPM self test failed\n");
+			if (rc > 0)
+				rc = -ENODEV;
+			goto out_err;
+		}
+	} else {
+		if (tpm_do_selftest(chip)) {
+			dev_err(dev, "TPM self test failed\n");
+			rc = -ENODEV;
+			goto out_err;
+		}
+	}
+
+	return tpm_chip_register(chip);
+
+out_err:
+	return rc;
+}
+EXPORT_SYMBOL(tpm_tis_init_core);
+
+#ifdef CONFIG_PM_SLEEP
+static void tpm_tis_reenable_interrupts(struct tpm_chip *chip)
+{
+	u32 intmask;
+
+	/* reenable interrupts that device may have lost or
+	 * BIOS/firmware may have disabled
+	 */
+	tpm_write_byte(chip, TPM_INT_VECTOR(chip->vendor.locality), chip->vendor.irq);
+
+
+	intmask = tpm_read_dword(chip, TPM_INT_ENABLE(chip->vendor.locality));
+
+	intmask |= TPM_INTF_CMD_READY_INT
+	    | TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_DATA_AVAIL_INT
+	    | TPM_INTF_STS_VALID_INT | TPM_GLOBAL_INT_ENABLE;
+
+	tpm_write_dword(chip, TPM_INT_ENABLE(chip->vendor.locality), intmask);
+}
+
+int tpm_tis_resume(struct device *dev)
+{
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+	int ret;
+
+	if (chip->vendor.irq)
+		tpm_tis_reenable_interrupts(chip);
+
+	ret = tpm_pm_resume(dev);
+	if (ret)
+		return ret;
+
+	/* TPM 1.2 requires self-test on resume. This function actually returns
+	 * an error code but for unknown reason it isn't handled.
+	 */
+	if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
+		tpm_do_selftest(chip);
+
+	return 0;
+}
+EXPORT_SYMBOL(tpm_tis_resume);
+#endif
diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h
new file mode 100644
index 0000000..2e2d188
--- /dev/null
+++ b/drivers/char/tpm/tpm_tis_core.h
@@ -0,0 +1,166 @@
+/*
+ * Copyright (C) 2005, 2006 IBM Corporation
+ * Copyright (C) 2014, 2015 Intel Corporation
+ *
+ * Authors:
+ * Leendert van Doorn <leendert@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 device driver implements the TPM interface as defined in
+ * the TCG TPM Interface Spec version 1.2, revision 1.0.
+ *
+ * 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.
+ */
+
+#ifndef __TPM_TIS_CORE_H
+#define __TPM_TIS_CORE_H
+
+#include "tpm.h"
+
+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,
+	TPM_STS_RESPONSE_RETRY = 0x02,
+};
+
+enum tis_int_flags {
+	TPM_GLOBAL_INT_ENABLE = 0x80000000,
+	TPM_INTF_BURST_COUNT_STATIC = 0x100,
+	TPM_INTF_CMD_READY_INT = 0x080,
+	TPM_INTF_INT_EDGE_FALLING = 0x040,
+	TPM_INTF_INT_EDGE_RISING = 0x020,
+	TPM_INTF_INT_LEVEL_LOW = 0x010,
+	TPM_INTF_INT_LEVEL_HIGH = 0x008,
+	TPM_INTF_LOCALITY_CHANGE_INT = 0x004,
+	TPM_INTF_STS_VALID_INT = 0x002,
+	TPM_INTF_DATA_AVAIL_INT = 0x001,
+};
+
+enum tis_defaults {
+	TIS_MEM_BASE = 0xFED40000,
+	TIS_MEM_LEN = 0x5000,
+	TIS_SHORT_TIMEOUT = 750,	/* ms */
+	TIS_LONG_TIMEOUT = 2000,	/* 2 sec */
+};
+
+/* Some timeout values are needed before it is known whether the chip is
+ * TPM 1.0 or TPM 2.0.
+ */
+#define TIS_TIMEOUT_A_MAX	max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_A)
+#define TIS_TIMEOUT_B_MAX	max(TIS_LONG_TIMEOUT, TPM2_TIMEOUT_B)
+#define TIS_TIMEOUT_C_MAX	max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_C)
+#define TIS_TIMEOUT_D_MAX	max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_D)
+
+#define	TPM_ACCESS(l)			(0x0000 | ((l) << 12))
+#define	TPM_INT_ENABLE(l)		(0x0008 | ((l) << 12))
+#define	TPM_INT_VECTOR(l)		(0x000C | ((l) << 12))
+#define	TPM_INT_STATUS(l)		(0x0010 | ((l) << 12))
+#define	TPM_INTF_CAPS(l)		(0x0014 | ((l) << 12))
+#define	TPM_STS(l)			(0x0018 | ((l) << 12))
+#define	TPM_STS3(l)			(0x001b | ((l) << 12))
+#define	TPM_DATA_FIFO(l)		(0x0024 | ((l) << 12))
+
+#define	TPM_DID_VID(l)			(0x0F00 | ((l) << 12))
+#define	TPM_RID(l)			(0x0F04 | ((l) << 12))
+
+struct tis_vendor_timeout_override {
+	u32 did_vid;
+	unsigned long timeout_us[4];
+};
+
+static const struct tis_vendor_timeout_override vendor_timeout_overrides[] = {
+	/* Atmel 3204 */
+	{ 0x32041114, { (TIS_SHORT_TIMEOUT * 1000), (TIS_LONG_TIMEOUT * 1000),
+			(TIS_SHORT_TIMEOUT * 1000), (TIS_SHORT_TIMEOUT * 1000) } },
+};
+
+u8 tpm_tis_status(struct tpm_chip *chip);
+void tpm_tis_ready(struct tpm_chip *chip);
+int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count);
+int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len);
+bool tpm_tis_update_timeouts(struct tpm_chip *chip,
+				    unsigned long *timeout_cap);
+bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status);
+int tpm_tis_resume(struct device *dev);
+void tpm_tis_remove(struct tpm_chip *chip);
+
+/* Helpers - read */
+static inline int tpm_read_bytes(struct tpm_chip *chip, u32 addr,
+				 size_t len, u8 *res)
+{
+	return chip->ops->read_bytes(chip, addr, len, 1, res);
+}
+static inline u8 tpm_read_byte(struct tpm_chip *chip, u32 addr)
+{
+	u8 res;
+
+	chip->ops->read_bytes(chip, addr, 1, sizeof(u8), &res);
+
+	return res;
+}
+
+static inline u16 tpm_read_word(struct tpm_chip *chip, u32 addr)
+{
+	u16 res;
+
+	chip->ops->read_bytes(chip, addr, 1, sizeof(u16), (u8 *)&res);
+	return res;
+}
+
+static inline u32 tpm_read_dword(struct tpm_chip *chip, u32 addr)
+{
+	u32 res;
+
+	chip->ops->read_bytes(chip, addr, 1, sizeof(u32), (u8 *)&res);
+	return res;
+}
+
+/* Helpers - write */
+static inline int tpm_write_bytes(struct tpm_chip *chip, u32 addr,
+				  size_t len, u8 *value)
+{
+	return chip->ops->write_bytes(chip, addr, 1, len, value);
+}
+
+static inline int tpm_write_byte(struct tpm_chip *chip, u32 addr, u8 value)
+{
+	u8 tmp = value;
+
+	return chip->ops->write_bytes(chip, addr, 1, sizeof(u8), &tmp);
+}
+
+static inline int tpm_write_word(struct tpm_chip *chip, u32 addr, u16 value)
+{
+	u32 tmp = value;
+
+	return chip->ops->write_bytes(chip, addr, 1, sizeof(u16), (u8 *)&tmp);
+}
+
+static inline int tpm_write_dword(struct tpm_chip *chip, u32 addr, u32 value)
+{
+	u32 tmp = value;
+
+	return chip->ops->write_bytes(chip, addr, 1, sizeof(u32), (u8 *)&tmp);
+}
+
+int tpm_tis_init_core(struct device *dev, struct tpm_chip *chip,
+		      int irq, int irq_flags);
+#endif
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 706e63e..f78e4fc 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -44,6 +44,10 @@ struct tpm_class_ops {
 	bool (*update_timeouts)(struct tpm_chip *chip,
 				unsigned long *timeout_cap);
 
+	int (*read_bytes)(struct tpm_chip *chip, u32 addr, size_t len,
+			  u8 size, u8 *dst);
+	int (*write_bytes)(struct tpm_chip *chip, u32 addr, size_t len,
+			   u8 size, u8 *src);
 };
 
 #if defined(CONFIG_TCG_TPM) || defined(CONFIG_TCG_TPM_MODULE)
