diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig
index 0eac596..99fc758 100644
--- a/drivers/char/tpm/Kconfig
+++ b/drivers/char/tpm/Kconfig
@@ -24,9 +24,16 @@ menuconfig TCG_TPM
 
 if TCG_TPM
 
+config TCG_TIS_CORE
+	tristate
+	---help---
+	TCG TIS TPM core driver. It implements the TPM TCG TIS logic and hooks
+	into the TPM kernel APIs. Physical layers will register against it.
+
 config TCG_TIS
 	tristate "TPM Interface Specification 1.2 Interface / TPM 2.0 FIFO Interface"
 	depends on X86
+	select TCG_TIS_CORE
 	---help---
 	  If you have a TPM security chip that is compliant with the
 	  TCG TIS 1.2 TPM specification (TPM1.2) or the TCG PTP FIFO
diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
index 98de5e6..662221f 100644
--- a/drivers/char/tpm/Makefile
+++ b/drivers/char/tpm/Makefile
@@ -12,6 +12,7 @@ ifdef CONFIG_TCG_IBMVTPM
 	tpm-y += tpm_eventlog.o tpm_of.o
 endif
 endif
+obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o
 obj-$(CONFIG_TCG_TIS) += tpm_tis.o
 obj-$(CONFIG_TCG_TIS_I2C_ATMEL) += tpm_i2c_atmel.o
 obj-$(CONFIG_TCG_TIS_I2C_INFINEON) += tpm_i2c_infineon.o
diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
index 1c94e0c..eaf5730 100644
--- a/drivers/char/tpm/tpm_tis.c
+++ b/drivers/char/tpm/tpm_tis.c
@@ -31,40 +31,6 @@
 #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,
-};
-
-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_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_LEN = 0x5000,
-	TIS_SHORT_TIMEOUT = 750,	/* ms */
-	TIS_LONG_TIMEOUT = 2000,	/* 2 sec */
-};
-
 struct tpm_info {
 	struct resource res;
 	/* irq > 0 means: use irq $irq;
@@ -74,26 +40,6 @@ 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 tpm_tis_tcg_phy {
 	struct tpm_tis_data priv;
 	void __iomem *iobase;
@@ -104,6 +50,20 @@ static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *da
 	return container_of(data, struct tpm_tis_tcg_phy, priv);
 }
 
+static bool interrupts = true;
+module_param(interrupts, bool, 0444);
+MODULE_PARM_DESC(interrupts, "Enable interrupts");
+
+static bool itpm;
+module_param(itpm, bool, 0444);
+MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)");
+
+static bool force;
+#ifdef CONFIG_X86
+module_param(force, bool, 0444);
+MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry");
+#endif
+
 #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
 static int has_hid(struct acpi_device *dev, const char *hid)
 {
@@ -127,484 +87,6 @@ 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)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	unsigned long stop = jiffies + chip->timeout_a;
-	int rc;
-	u8 access;
-
-	do {
-		rc = tpm_read8(priv, TPM_ACCESS(l), &access);
-		if (rc < 0)
-			return rc;
-
-		if (access & 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)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	int rc;
-	u8 access;
-
-	rc = tpm_read8(priv, TPM_ACCESS(l), &access);
-	if (rc < 0)
-		return rc;
-
-	if ((access & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
-	    (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
-		return priv->locality = l;
-
-	return -1;
-}
-
-static void release_locality(struct tpm_chip *chip, int l, int force)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	int rc;
-	u8 access;
-
-	rc = tpm_read8(priv, TPM_ACCESS(l), &access);
-	if (rc < 0)
-		return;
-
-	if (force || (access &
-		      (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) ==
-	    (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID))
-		tpm_write8(priv, TPM_ACCESS(l), TPM_ACCESS_ACTIVE_LOCALITY);
-
-}
-
-static int request_locality(struct tpm_chip *chip, int l)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	unsigned long stop, timeout;
-	long rc;
-
-	if (check_locality(chip, l) >= 0)
-		return l;
-
-	rc = tpm_write8(priv, TPM_ACCESS(l), TPM_ACCESS_REQUEST_USE);
-	if (rc < 0)
-		return rc;
-
-	stop = jiffies + chip->timeout_a;
-
-	if (chip->flags & TPM_CHIP_FLAG_IRQ) {
-again:
-		timeout = stop - jiffies;
-		if ((long)timeout <= 0)
-			return -1;
-		rc = wait_event_interruptible_timeout(priv->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)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	int rc;
-	u8 status;
-
-	rc = tpm_read8(priv, TPM_STS(priv->locality), &status);
-	if (rc < 0)
-		return 0;
-
-	return status;
-}
-
-static void tpm_tis_ready(struct tpm_chip *chip)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-
-	/* this causes the current command to be aborted */
-	tpm_write8(priv, TPM_STS(priv->locality), TPM_STS_COMMAND_READY);
-}
-
-static int get_burstcount(struct tpm_chip *chip)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	unsigned long stop;
-	int burstcnt, rc;
-	u8 value;
-
-	/* wait for burstcount */
-	/* which timeout value, spec has 2 answers (c & d) */
-	stop = jiffies + chip->timeout_d;
-	do {
-		rc = tpm_read8(priv, TPM_STS(priv->locality) + 1, &value);
-		if (rc < 0)
-			return rc;
-
-		burstcnt = value;
-		rc = tpm_read8(priv, TPM_STS(priv->locality) + 2, &value);
-		if (rc < 0)
-			return rc;
-
-		burstcnt += value << 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)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	int size = 0, burstcnt, rc;
-
-	while (size < count &&
-	       wait_for_tpm_stat(chip,
-				 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
-				 chip->timeout_c,
-				 &priv->read_queue, true) == 0) {
-		burstcnt = min_t(int, get_burstcount(chip), count - size);
-		rc = tpm_read_bytes(priv, TPM_DATA_FIFO(priv->locality),
-				    burstcnt, buf + size);
-		if (rc < 0)
-			return rc;
-
-		size += burstcnt;
-	}
-	return size;
-}
-
-static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	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->timeout_c,
-			  &priv->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, priv->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)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	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->timeout_b,
-		     &priv->int_queue, false) < 0) {
-			rc = -ETIME;
-			goto out_err;
-		}
-	}
-
-	while (count < len - 1) {
-		burstcnt = min_t(int, get_burstcount(chip), len - count - 1);
-		rc = tpm_write_bytes(priv, TPM_DATA_FIFO(priv->locality),
-				     burstcnt, buf + count);
-		if (rc < 0)
-			goto out_err;
-
-		count += burstcnt;
-
-		wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
-				  &priv->int_queue, false);
-		status = tpm_tis_status(chip);
-		if (!itpm && (status & TPM_STS_DATA_EXPECT) == 0) {
-			rc = -EIO;
-			goto out_err;
-		}
-	}
-
-	/* write last byte */
-	rc = tpm_write8(priv, TPM_DATA_FIFO(priv->locality), buf[count]);
-	if (rc < 0)
-		goto out_err;
-
-	wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
-			  &priv->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, priv->locality, 0);
-	return rc;
-}
-
-static void disable_interrupts(struct tpm_chip *chip)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	u32 intmask;
-	int rc;
-
-	rc = tpm_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
-	if (rc < 0)
-		intmask = 0;
-
-	intmask &= ~TPM_GLOBAL_INT_ENABLE;
-	tpm_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
-
-	devm_free_irq(&chip->dev, priv->irq, chip);
-	priv->irq = 0;
-	chip->flags &= ~TPM_CHIP_FLAG_IRQ;
-}
-
-/*
- * 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)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	int rc;
-	u32 ordinal;
-	unsigned long dur;
-
-	rc = tpm_tis_send_data(chip, buf, len);
-	if (rc < 0)
-		return rc;
-
-	/* go and do it */
-	rc = tpm_write8(priv, TPM_STS(priv->locality), TPM_STS_GO);
-	if (rc < 0)
-		return rc;
-
-	if (chip->flags & TPM_CHIP_FLAG_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,
-		     &priv->read_queue, false) < 0) {
-			rc = -ETIME;
-			goto out_err;
-		}
-	}
-	return len;
-out_err:
-	tpm_tis_ready(chip);
-	release_locality(chip, priv->locality, 0);
-	return rc;
-}
-
-static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	int rc, irq;
-
-	if (!(chip->flags & TPM_CHIP_FLAG_IRQ) || priv->irq_tested)
-		return tpm_tis_send_main(chip, buf, len);
-
-	/* Verify receipt of the expected IRQ */
-	irq = priv->irq;
-	priv->irq = 0;
-	chip->flags &= ~TPM_CHIP_FLAG_IRQ;
-	rc = tpm_tis_send_main(chip, buf, len);
-	priv->irq = irq;
-	chip->flags |= TPM_CHIP_FLAG_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)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	int i, rc;
-	u32 did_vid;
-
-	rc = tpm_read32(priv, TPM_DID_VID(0), &did_vid);
-	if (rc < 0)
-		return rc;
-
-	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)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	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;
-
-	rc = tpm_read16(priv, TPM_DID_VID(0), &vendor);
-	if (rc < 0)
-		return rc;
-
-	/* 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, priv->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, priv->locality, 0);
-
-	return rc;
-}
-
-static bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-
-	switch (priv->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,
-	.send = tpm_tis_send,
-	.cancel = tpm_tis_ready,
-	.update_timeouts = tpm_tis_update_timeouts,
-	.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,
-};
-
 static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 			      u8 *result)
 {
@@ -657,364 +139,29 @@ static const struct tpm_tis_phy_ops tpm_tcg = {
 	.write32 = tpm_tcg_write32,
 };
 
-static irqreturn_t tis_int_handler(int dummy, void *dev_id)
-{
-	struct tpm_chip *chip = dev_id;
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	u32 interrupt;
-	int i, rc;
-
-	rc = tpm_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
-	if (rc < 0)
-		return IRQ_NONE;
-
-	if (interrupt == 0)
-		return IRQ_NONE;
-
-	priv->irq_tested = true;
-	if (interrupt & TPM_INTF_DATA_AVAIL_INT)
-		wake_up_interruptible(&priv->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(&priv->int_queue);
-
-	/* Clear interrupts handled with TPM_EOI */
-	rc = tpm_write32(priv, TPM_INT_STATUS(priv->locality), interrupt);
-	if (rc < 0)
-		return IRQ_NONE;
-
-	tpm_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
-	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 tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	u8 original_int_vec;
-	int rc;
-	u32 int_status;
-
-	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;
-	}
-	priv->irq = irq;
-
-	rc = tpm_read8(priv, TPM_INT_VECTOR(priv->locality), &original_int_vec);
-	if (rc < 0)
-		return rc;
-
-	rc = tpm_write8(priv, TPM_INT_VECTOR(priv->locality), irq);
-	if (rc < 0)
-		return rc;
-
-	rc = tpm_read32(priv, TPM_INT_STATUS(priv->locality), &int_status);
-	if (rc < 0)
-		return rc;
-
-	/* Clear all existing */
-	rc = tpm_write32(priv, TPM_INT_STATUS(priv->locality), int_status);
-	if (rc < 0)
-		return rc;
-
-	/* Turn on */
-	rc = tpm_write32(priv, TPM_INT_ENABLE(priv->locality),
-			 intmask | TPM_GLOBAL_INT_ENABLE);
-	if (rc < 0)
-		return rc;
-
-	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->flags & TPM_CHIP_FLAG_IRQ)) {
-		rc = tpm_write8(priv, TPM_INT_VECTOR(priv->locality),
-				original_int_vec);
-		if (rc < 0)
-			return rc;
-
-		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)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	u8 original_int_vec;
-	int i, rc;
-
-	rc = tpm_read8(priv, TPM_INT_VECTOR(priv->locality), &original_int_vec);
-	if (rc < 0)
-		return;
-
-	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)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	u32 reg = TPM_INT_ENABLE(priv->locality);
-	u32 interrupt;
-	int rc;
-
-	rc = tpm_read32(priv, reg, &interrupt);
-	if (rc < 0)
-		interrupt = 0;
-
-	tpm_write32(priv, reg, ~TPM_GLOBAL_INT_ENABLE & interrupt);
-	release_locality(chip, priv->locality, 1);
-}
-
 static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info,
 			acpi_handle acpi_dev_handle)
 {
-	u32 vendor, intfcaps, intmask;
-	u8 rid;
-	int rc, probe;
-	struct tpm_chip *chip;
 	struct tpm_tis_tcg_phy *phy;
+	int irq = -1;
 
 	phy = devm_kzalloc(dev, sizeof(struct tpm_tis_tcg_phy), GFP_KERNEL);
 	if (phy == NULL)
 		return -ENOMEM;
 
-	chip = tpmm_chip_alloc(dev, &tpm_tis);
-	if (IS_ERR(chip))
-		return PTR_ERR(chip);
-
-#ifdef CONFIG_ACPI
-	chip->acpi_dev_handle = acpi_dev_handle;
-#endif
-
 	phy->iobase = devm_ioremap_resource(dev, &tpm_info->res);
 	if (IS_ERR(phy->iobase))
 		return PTR_ERR(phy->iobase);
 
-	phy->priv.phy_ops = &tpm_tcg;
-
-	/* Maximum timeouts */
-	chip->timeout_a = TIS_TIMEOUT_A_MAX;
-	chip->timeout_b = TIS_TIMEOUT_B_MAX;
-	chip->timeout_c = TIS_TIMEOUT_C_MAX;
-	chip->timeout_d = TIS_TIMEOUT_D_MAX;
-
-	dev_set_drvdata(&chip->dev, &phy->priv);
-
-	if (wait_startup(chip, 0) != 0) {
-		rc = -ENODEV;
-		goto out_err;
-	}
-
-	/* Take control of the TPM's interrupt hardware and shut it off */
-	rc = tpm_read32(&phy->priv, TPM_INT_ENABLE(phy->priv.locality),
-			&intmask);
-	if (rc < 0)
-		goto out_err;
-
-	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_write32(&phy->priv, TPM_INT_ENABLE(phy->priv.locality), intmask);
-
-	if (request_locality(chip, 0) != 0) {
-		rc = -ENODEV;
-		goto out_err;
-	}
-
-	rc = tpm2_probe(chip);
-	if (rc)
-		goto out_err;
-
-	rc = tpm_read32(&phy->priv, TPM_DID_VID(0), &vendor);
-	if (rc < 0)
-		goto out_err;
-
-	phy->priv.manufacturer_id = vendor;
-
-	rc = tpm_read8(&phy->priv, TPM_RID(0), &rid);
-	if (rc < 0)
-		goto out_err;
-
-	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, rid);
-
-	if (!itpm) {
-		probe = probe_itpm(chip);
-		if (probe < 0) {
-			rc = -ENODEV;
-			goto out_err;
-		}
-		itpm = !!probe;
-	}
+	if (interrupts)
+		irq = tpm_info->irq;
 
 	if (itpm)
-		dev_info(dev, "Intel iTPM workaround enabled\n");
-
-	/* Figure out the capabilities */
-	rc = tpm_read32(&phy->priv, TPM_INTF_CAPS(phy->priv.locality),
-			&intfcaps);
-	if (rc < 0)
-		goto out_err;
-
-	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;
-	}
+		phy->priv.flags |= TPM_TIS_ITPM_POSSIBLE;
 
-	/* INTERRUPT Setup */
-	init_waitqueue_head(&phy->priv.read_queue);
-	init_waitqueue_head(&phy->priv.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->flags & TPM_CHIP_FLAG_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)
-{
-	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
-	u32 intmask;
-	int rc;
-
-	/* reenable interrupts that device may have lost or
-	   BIOS/firmware may have disabled */
-	rc = tpm_write8(priv, TPM_INT_VECTOR(priv->locality), priv->irq);
-	if (rc < 0)
-		return;
-
-	rc = tpm_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
-	if (rc < 0)
-		return;
-
-	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_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
-}
-
-static int tpm_tis_resume(struct device *dev)
-{
-	struct tpm_chip *chip = dev_get_drvdata(dev);
-	int ret;
-
-	if (chip->flags & TPM_CHIP_FLAG_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;
+	return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg,
+				 acpi_dev_handle);
 }
-#endif
 
 static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
 
@@ -1216,12 +363,6 @@ static struct platform_driver tis_drv = {
 	},
 };
 
-static bool force;
-#ifdef CONFIG_X86
-module_param(force, bool, 0444);
-MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry");
-#endif
-
 static int tpm_tis_force_device(void)
 {
 	struct platform_device *pdev;
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
new file mode 100644
index 0000000..f4e05ac
--- /dev/null
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -0,0 +1,860 @@
+/*
+ * 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"
+
+/* 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)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	unsigned long stop = jiffies + chip->timeout_a;
+
+	do {
+		int rc;
+		u8 access;
+
+		rc = tpm_read8(priv, TPM_ACCESS(l), &access);
+		if (rc < 0)
+			return rc;
+
+		if (access & 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)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	int rc;
+	u8 access;
+
+	rc = tpm_read8(priv, TPM_ACCESS(l), &access);
+	if (rc < 0)
+		return rc;
+
+	if ((access & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
+	    (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
+		return priv->locality = l;
+
+	return -1;
+}
+
+static void release_locality(struct tpm_chip *chip, int l, int force)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	int rc;
+	u8 access;
+
+	rc = tpm_read8(priv, TPM_ACCESS(l), &access);
+	if (rc < 0)
+		return;
+
+	if (force || (access &
+		      (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) ==
+	    (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID))
+		tpm_write8(priv, TPM_ACCESS(l), TPM_ACCESS_ACTIVE_LOCALITY);
+
+}
+
+static int request_locality(struct tpm_chip *chip, int l)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	unsigned long stop, timeout;
+	long rc;
+
+	if (check_locality(chip, l) >= 0)
+		return l;
+
+	rc = tpm_write8(priv, TPM_ACCESS(l), TPM_ACCESS_REQUEST_USE);
+	if (rc < 0)
+		return rc;
+
+	stop = jiffies + chip->timeout_a;
+
+	if (chip->flags & TPM_CHIP_FLAG_IRQ) {
+again:
+		timeout = stop - jiffies;
+		if ((long)timeout <= 0)
+			return -1;
+		rc = wait_event_interruptible_timeout(priv->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)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	int rc;
+	u8 status;
+
+	rc = tpm_read8(priv, TPM_STS(priv->locality), &status);
+	if (rc < 0)
+		return 0;
+
+	return status;
+}
+
+static void tpm_tis_ready(struct tpm_chip *chip)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+
+	/* this causes the current command to be aborted */
+	tpm_write8(priv, TPM_STS(priv->locality), TPM_STS_COMMAND_READY);
+}
+
+static int get_burstcount(struct tpm_chip *chip)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	unsigned long stop;
+	int burstcnt, rc;
+	u8 value;
+
+	/* wait for burstcount */
+	/* which timeout value, spec has 2 answers (c & d) */
+	stop = jiffies + chip->timeout_d;
+	do {
+		rc = tpm_read8(priv, TPM_STS(priv->locality) + 1, &value);
+		if (rc < 0)
+			return rc;
+
+		burstcnt = value;
+		rc = tpm_read8(priv, TPM_STS(priv->locality) + 2, &value);
+		if (rc < 0)
+			return rc;
+
+		burstcnt += value << 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)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	int size = 0, burstcnt, rc;
+
+	while (size < count &&
+	       wait_for_tpm_stat(chip,
+				 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
+				 chip->timeout_c,
+				 &priv->read_queue, true) == 0) {
+		burstcnt = min_t(int, get_burstcount(chip), count - size);
+
+		rc = tpm_read_bytes(priv, TPM_DATA_FIFO(priv->locality),
+				    burstcnt, buf + size);
+		if (rc < 0)
+			return rc;
+
+		size += burstcnt;
+	}
+	return size;
+}
+
+static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	int size = 0;
+	int expected, status;
+
+	if (count < TPM_HEADER_SIZE) {
+		size = -EIO;
+		goto out;
+	}
+
+	size = recv_data(chip, buf, TPM_HEADER_SIZE);
+	/* read first 10 bytes, including tag, paramsize, and result */
+	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->timeout_c,
+			  &priv->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, priv->locality, 0);
+	return size;
+}
+
+/*
+ * 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)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	int rc, status, burstcnt;
+	size_t count = 0;
+	bool itpm = priv->flags & TPM_TIS_ITPM_POSSIBLE;
+
+	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->timeout_b,
+		     &priv->int_queue, false) < 0) {
+			rc = -ETIME;
+			goto out_err;
+		}
+	}
+
+	while (count < len - 1) {
+		burstcnt = min_t(int, get_burstcount(chip), len - count - 1);
+		rc = tpm_write_bytes(priv, TPM_DATA_FIFO(priv->locality),
+				     burstcnt, buf + count);
+		if (rc < 0)
+			goto out_err;
+
+		count += burstcnt;
+
+		wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
+				  &priv->int_queue, false);
+		status = tpm_tis_status(chip);
+		if (!itpm && (status & TPM_STS_DATA_EXPECT) == 0) {
+			rc = -EIO;
+			goto out_err;
+		}
+	}
+
+	/* write last byte */
+	rc = tpm_write8(priv, TPM_DATA_FIFO(priv->locality), buf[count]);
+	if (rc < 0)
+		goto out_err;
+
+	wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
+			  &priv->int_queue, false);
+	status = tpm_tis_status(chip);
+	if (!itpm && (status & TPM_STS_DATA_EXPECT) != 0) {
+		rc = -EIO;
+		goto out_err;
+	}
+
+	return 0;
+
+out_err:
+	tpm_tis_ready(chip);
+	release_locality(chip, priv->locality, 0);
+	return rc;
+}
+
+static void disable_interrupts(struct tpm_chip *chip)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	u32 intmask;
+	int rc;
+
+	rc = tpm_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
+	if (rc < 0)
+		intmask = 0;
+
+	intmask &= ~TPM_GLOBAL_INT_ENABLE;
+	rc = tpm_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
+
+	devm_free_irq(&chip->dev, priv->irq, chip);
+	priv->irq = 0;
+	chip->flags &= ~TPM_CHIP_FLAG_IRQ;
+}
+
+/*
+ * 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)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	int rc;
+	u32 ordinal;
+	unsigned long dur;
+
+	rc = tpm_tis_send_data(chip, buf, len);
+	if (rc < 0)
+		return rc;
+
+	/* go and do it */
+	rc = tpm_write8(priv, TPM_STS(priv->locality), TPM_STS_GO);
+	if (rc < 0)
+		goto out_err;
+
+	if (chip->flags & TPM_CHIP_FLAG_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,
+		     &priv->read_queue, false) < 0) {
+			rc = -ETIME;
+			goto out_err;
+		}
+	}
+	return len;
+out_err:
+	tpm_tis_ready(chip);
+	release_locality(chip, priv->locality, 0);
+	return rc;
+}
+
+static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
+{
+	int rc, irq;
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+
+	if (!(chip->flags & TPM_CHIP_FLAG_IRQ) || priv->irq_tested)
+		return tpm_tis_send_main(chip, buf, len);
+
+	/* Verify receipt of the expected IRQ */
+	irq = priv->irq;
+	priv->irq = 0;
+	chip->flags &= ~TPM_CHIP_FLAG_IRQ;
+	rc = tpm_tis_send_main(chip, buf, len);
+	priv->irq = irq;
+	chip->flags |= TPM_CHIP_FLAG_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)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	int i, rc;
+	u32 did_vid;
+
+	rc = tpm_read32(priv, TPM_DID_VID(0), &did_vid);
+	if (rc < 0)
+		return rc;
+
+	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)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	int rc = 0;
+	u8 cmd_getticks[] = {
+		0x00, 0xc1, 0x00, 0x00, 0x00, 0x0a,
+		0x00, 0x00, 0x00, 0xf1
+	};
+	size_t len = sizeof(cmd_getticks);
+	bool itpm;
+	u16 vendor;
+
+	rc = tpm_read16(priv, TPM_DID_VID(0), &vendor);
+	if (rc < 0)
+		return rc;
+
+	/* 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, priv->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:
+	tpm_tis_ready(chip);
+	release_locality(chip, priv->locality, 0);
+
+	return rc;
+}
+
+static bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+
+	switch (priv->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 irqreturn_t tis_int_handler(int dummy, void *dev_id)
+{
+	struct tpm_chip *chip = dev_id;
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	u32 interrupt;
+	int i, rc;
+
+	rc = tpm_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
+	if (rc < 0)
+		return IRQ_NONE;
+
+	if (interrupt == 0)
+		return IRQ_NONE;
+
+	priv->irq_tested = true;
+	if (interrupt & TPM_INTF_DATA_AVAIL_INT)
+		wake_up_interruptible(&priv->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(&priv->int_queue);
+
+	/* Clear interrupts handled with TPM_EOI */
+	rc = tpm_write32(priv, TPM_INT_STATUS(priv->locality), interrupt);
+	if (rc < 0)
+		return IRQ_NONE;
+
+	tpm_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
+	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 tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	u8 original_int_vec;
+	int rc;
+	u32 int_status;
+
+	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;
+	}
+	priv->irq = irq;
+
+	rc = tpm_read8(priv, TPM_INT_VECTOR(priv->locality), &original_int_vec);
+	if (rc < 0)
+		return rc;
+
+	rc = tpm_write8(priv, TPM_INT_VECTOR(priv->locality), irq);
+	if (rc < 0)
+		return rc;
+
+	rc = tpm_read32(priv, TPM_INT_STATUS(priv->locality), &int_status);
+	if (rc < 0)
+		return rc;
+
+	/* Clear all existing */
+	rc = tpm_write32(priv, TPM_INT_STATUS(priv->locality), int_status);
+	if (rc < 0)
+		return rc;
+
+	/* Turn on */
+	rc = tpm_write32(priv, TPM_INT_ENABLE(priv->locality),
+			 intmask | TPM_GLOBAL_INT_ENABLE);
+	if (rc < 0)
+		return rc;
+
+	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->flags & TPM_CHIP_FLAG_IRQ)) {
+		rc = tpm_write8(priv, original_int_vec,
+				TPM_INT_VECTOR(priv->locality));
+		if (rc < 0)
+			return rc;
+
+		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)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	u8 original_int_vec;
+	int i, rc;
+
+	rc = tpm_read8(priv, TPM_INT_VECTOR(priv->locality), &original_int_vec);
+	if (rc < 0)
+		return;
+
+	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)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	u32 reg = TPM_INT_ENABLE(priv->locality);
+	u32 interrupt;
+	int rc;
+
+	rc = tpm_read32(priv, reg, &interrupt);
+	if (rc < 0)
+		interrupt = 0;
+
+	tpm_write32(priv, reg, ~TPM_GLOBAL_INT_ENABLE & interrupt);
+	release_locality(chip, priv->locality, 1);
+}
+EXPORT_SYMBOL_GPL(tpm_tis_remove);
+
+static const struct tpm_class_ops tpm_tis = {
+	.status = tpm_tis_status,
+	.recv = tpm_tis_recv,
+	.send = tpm_tis_send,
+	.cancel = tpm_tis_ready,
+	.update_timeouts = tpm_tis_update_timeouts,
+	.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,
+};
+
+int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
+		      const struct tpm_tis_phy_ops *phy_ops,
+		      acpi_handle acpi_dev_handle)
+{
+	u32 vendor, intfcaps, intmask;
+	u8 rid;
+	int rc, probe;
+	struct tpm_chip *chip;
+
+	chip = tpmm_chip_alloc(dev, &tpm_tis);
+	if (IS_ERR(chip))
+		return PTR_ERR(chip);
+
+#ifdef CONFIG_ACPI
+	chip->acpi_dev_handle = acpi_dev_handle;
+#endif
+
+	/* Maximum timeouts */
+	chip->timeout_a = TIS_TIMEOUT_A_MAX;
+	chip->timeout_b = TIS_TIMEOUT_B_MAX;
+	chip->timeout_c = TIS_TIMEOUT_C_MAX;
+	chip->timeout_d = TIS_TIMEOUT_D_MAX;
+	priv->phy_ops = phy_ops;
+	dev_set_drvdata(&chip->dev, priv);
+
+	if (wait_startup(chip, 0) != 0) {
+		rc = -ENODEV;
+		goto out_err;
+	}
+
+	/* Take control of the TPM's interrupt hardware and shut it off */
+	rc = tpm_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
+	if (rc < 0)
+		goto out_err;
+
+	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_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
+
+	if (request_locality(chip, 0) != 0) {
+		rc = -ENODEV;
+		goto out_err;
+	}
+
+	rc = tpm2_probe(chip);
+	if (rc)
+		goto out_err;
+
+	rc = tpm_read32(priv, TPM_DID_VID(0), &vendor);
+	if (rc < 0)
+		goto out_err;
+
+	priv->manufacturer_id = vendor;
+
+	rc = tpm_read8(priv, TPM_RID(0), &rid);
+	if (rc < 0)
+		goto out_err;
+
+	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, rid);
+
+	if (!(priv->flags & TPM_TIS_ITPM_POSSIBLE)) {
+		probe = probe_itpm(chip);
+		if (probe < 0) {
+			rc = -ENODEV;
+			goto out_err;
+		}
+
+		if (!!probe)
+			priv->flags |= TPM_TIS_ITPM_POSSIBLE;
+	}
+
+	/* Figure out the capabilities */
+	rc = tpm_read32(priv, TPM_INTF_CAPS(priv->locality), &intfcaps);
+	if (rc < 0)
+		goto out_err;
+
+	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(&priv->read_queue);
+	init_waitqueue_head(&priv->int_queue);
+	if (irq != -1) {
+		if (irq) {
+			tpm_tis_probe_irq_single(chip, intmask, IRQF_SHARED,
+						 irq);
+			if (!(chip->flags & TPM_CHIP_FLAG_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;
+}
+EXPORT_SYMBOL_GPL(tpm_tis_core_init);
+
+#ifdef CONFIG_PM_SLEEP
+static void tpm_tis_reenable_interrupts(struct tpm_chip *chip)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	u32 intmask;
+	int rc;
+
+	/* reenable interrupts that device may have lost or
+	 * BIOS/firmware may have disabled
+	 */
+	rc = tpm_write8(priv, TPM_INT_VECTOR(priv->locality), priv->irq);
+	if (rc < 0)
+		return;
+
+	rc = tpm_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
+	if (rc < 0)
+		return;
+
+	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_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
+}
+
+int tpm_tis_resume(struct device *dev)
+{
+	struct tpm_chip *chip = dev_get_drvdata(dev);
+	int ret;
+
+	if (chip->flags & TPM_CHIP_FLAG_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_GPL(tpm_tis_resume);
+#endif
+
+MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
+MODULE_DESCRIPTION("TPM Driver");
+MODULE_VERSION("2.0");
+MODULE_LICENSE("GPL");
diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h
index 75e16d0..91aa305 100644
--- a/drivers/char/tpm/tpm_tis_core.h
+++ b/drivers/char/tpm/tpm_tis_core.h
@@ -25,11 +25,70 @@
 
 #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,
+};
+
+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_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))
+
+enum tpm_tis_flags {
+	TPM_TIS_ITPM_POSSIBLE		= BIT(0),
+};
+
 struct tpm_tis_data {
 	u16 manufacturer_id;
 	int locality;
 	int irq;
 	bool irq_tested;
+	unsigned int flags;
 	wait_queue_head_t int_queue;
 	wait_queue_head_t read_queue;
 	const struct tpm_tis_phy_ops *phy_ops;
@@ -82,4 +141,13 @@ static inline int tpm_write32(struct tpm_tis_data *data, u32 addr, u32 value)
 	return data->phy_ops->write32(data, addr, value);
 }
 
+void tpm_tis_remove(struct tpm_chip *chip);
+int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
+		      const struct tpm_tis_phy_ops *phy_ops,
+		      acpi_handle acpi_dev_handle);
+
+#ifdef CONFIG_PM_SLEEP
+int tpm_tis_resume(struct device *dev);
+#endif
+
 #endif
