text: /*
   * 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_tis_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_tis_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_tis_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_tis_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_tis_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_tis_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_tis_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;
  	u32 value;
  
  	/* wait for burstcount */
  	if (chip->flags & TPM_CHIP_FLAG_TPM2)
  		stop = jiffies + chip->timeout_a;
  	else
  		stop = jiffies + chip->timeout_d;
  	do {
  		rc = tpm_tis_read32(priv, TPM_STS(priv->locality), &value);
  		if (rc < 0)
  			return rc;
  
  		burstcnt = (value >> 8) & 0xFFFF;
  		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 = get_burstcount(chip);
  		if (burstcnt < 0) {
  			dev_err(&chip->dev, "Unable to read burstcount\n");
  			return burstcnt;
  		}
  		burstcnt = min_t(int, burstcnt, count - size);
  
  		rc = tpm_tis_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 status;
  	u32 expected;
  
  	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 || expected < TPM_HEADER_SIZE) {
  		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, const 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 = get_burstcount(chip);
  		if (burstcnt < 0) {
  			dev_err(&chip->dev, "Unable to read burstcount\n");
  			rc = burstcnt;
  			goto out_err;
  		}
  		burstcnt = min_t(int, burstcnt, len - count - 1);
  		rc = tpm_tis_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_tis_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;
  
  	if (priv->irq == 0)
  		return;
  
  	rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
  	if (rc < 0)
  		intmask = 0;
  
  	intmask &= ~TPM_GLOBAL_INT_ENABLE;
  	rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
  
  	devm_free_irq(chip->dev.parent, 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, const 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_tis_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_tis_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);
  	u16 vendor;
  
  	rc = tpm_tis_read16(priv, TPM_DID_VID(0), &vendor);
  	if (rc < 0)
  		return rc;
  
  	/* probe only iTPMS */
  	if (vendor != TPM_VID_INTEL)
  		return 0;
  
  	rc = tpm_tis_send_data(chip, cmd_getticks, len);
  	if (rc == 0)
  		goto out;
  
  	tpm_tis_ready(chip);
  	release_locality(chip, priv->locality, 0);
  
  	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_tis_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_tis_write32(priv, TPM_INT_STATUS(priv->locality), interrupt);
  	if (rc < 0)
  		return IRQ_NONE;
  
  	tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
  	return IRQ_HANDLED;
  }
  
  static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
  {
  	const char *desc = "attempting to generate an interrupt";
  	u32 cap2;
  	cap_t cap;
  
  	if (chip->flags & TPM_CHIP_FLAG_TPM2)
  		return tpm2_get_tpm_pt(chip, 0x100, &cap2, desc);
  	else
  		return tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc);
  }
  
  /* 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.parent, 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_tis_read8(priv, TPM_INT_VECTOR(priv->locality),
  			   &original_int_vec);
  	if (rc < 0)
  		return rc;
  
  	rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), irq);
  	if (rc < 0)
  		return rc;
  
  	rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &int_status);
  	if (rc < 0)
  		return rc;
  
  	/* Clear all existing */
  	rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), int_status);
  	if (rc < 0)
  		return rc;
  
  	/* Turn on */
  	rc = tpm_tis_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
  	 */
  	rc = tpm_tis_gen_interrupt(chip);
  	if (rc < 0)
  		return rc;
  
  	/* 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_tis_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_tis_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_tis_read32(priv, reg, &interrupt);
  	if (rc < 0)
  		interrupt = 0;
  
  	tpm_tis_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 = {
  	.flags = TPM_OPS_AUTO_STARTUP,
  	.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 = msecs_to_jiffies(TIS_TIMEOUT_A_MAX);
  	chip->timeout_b = msecs_to_jiffies(TIS_TIMEOUT_B_MAX);
  	chip->timeout_c = msecs_to_jiffies(TIS_TIMEOUT_C_MAX);
  	chip->timeout_d = msecs_to_jiffies(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_tis_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_tis_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_tis_read32(priv, TPM_DID_VID(0), &vendor);
  	if (rc < 0)
  		goto out_err;
  
  	priv->manufacturer_id = vendor;
  
  	rc = tpm_tis_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_tis_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");
  
  				disable_interrupts(chip);
  			}
  		} else {
  			tpm_tis_probe_irq(chip, intmask);
  		}
  	}
  
  	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_tis_write8(priv, TPM_INT_VECTOR(priv->locality), priv->irq);
  	if (rc < 0)
  		return;
  
  	rc = tpm_tis_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_tis_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");
  