dm: tpm: Convert I2C driver to driver model

Convert the tpm_tis_i2c driver to use driver model and update boards which
use it.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Christophe Ricard<christophe-h.ricard@st.com>
Reviewed-by: Heiko Schocher <hs@denx.de>

2 files changed, 203 insertions, 346 deletions

diff --git a/drivers/tpm/tpm_tis_i2c.c b/drivers/tpm/tpm_tis_i2c.c
index 645f702215..9afe46c1e9 100644
--- a/drivers/tpm/tpm_tis_i2c.c
+++ b/drivers/tpm/tpm_tis_i2c.c
@@ -23,11 +23,11 @@
 #include <common.h>
 #include <dm.h>
 #include <fdtdec.h>
-#include <linux/compiler.h>
 #include <i2c.h>
 #include <tis.h>
 #include <tpm.h>
 #include <asm-generic/errno.h>
+#include <linux/compiler.h>
 #include <linux/types.h>
 #include <linux/unaligned/be_byteshift.h>
 
@@ -42,8 +42,6 @@ static const char * const chip_name[] = {
 	[UNKNOWN] = "unknown/fallback to slb9635",
 };
 
-static struct tpm_chip g_chip;
-
 /*
  * tpm_tis_i2c_read() - read from TPM register
  * @addr: register address to read from
@@ -58,22 +56,24 @@ static struct tpm_chip g_chip;
  *
  * Return -EIO on error, 0 on success.
  */
-static int tpm_tis_i2c_read(u8 addr, u8 *buffer, size_t len)
+static int tpm_tis_i2c_read(struct udevice *dev, u8 addr, u8 *buffer,
+			    size_t len)
 {
+	struct tpm_chip *chip = dev_get_priv(dev);
 	int rc;
 	int count;
 	uint32_t addrbuf = addr;
 
-	if ((g_chip.chip_type == SLB9635) || (g_chip.chip_type == UNKNOWN)) {
+	if ((chip->chip_type == SLB9635) || (chip->chip_type == UNKNOWN)) {
 		/* slb9635 protocol should work in both cases */
 		for (count = 0; count < MAX_COUNT; count++) {
-			rc = dm_i2c_write(g_chip.dev, 0, (uchar *)&addrbuf, 1);
+			rc = dm_i2c_write(dev, 0, (uchar *)&addrbuf, 1);
 			if (rc == 0)
 				break;  /* Success, break to skip sleep */
 			udelay(SLEEP_DURATION_US);
 		}
 		if (rc)
-			return -rc;
+			return rc;
 
 		/* After the TPM has successfully received the register address
 		 * it needs some time, thus we're sleeping here again, before
@@ -81,7 +81,7 @@ static int tpm_tis_i2c_read(u8 addr, u8 *buffer, size_t len)
 		 */
 		for (count = 0; count < MAX_COUNT; count++) {
 			udelay(SLEEP_DURATION_US);
-			rc = dm_i2c_read(g_chip.dev, 0, buffer, len);
+			rc = dm_i2c_read(dev, 0, buffer, len);
 			if (rc == 0)
 				break;  /* success, break to skip sleep */
 		}
@@ -94,7 +94,7 @@ static int tpm_tis_i2c_read(u8 addr, u8 *buffer, size_t len)
 		 * be safe on the safe side.
 		 */
 		for (count = 0; count < MAX_COUNT; count++) {
-			rc = dm_i2c_read(g_chip.dev, addr, buffer, len);
+			rc = dm_i2c_read(dev, addr, buffer, len);
 			if (rc == 0)
 				break;  /* break here to skip sleep */
 			udelay(SLEEP_DURATION_US);
@@ -104,19 +104,31 @@ static int tpm_tis_i2c_read(u8 addr, u8 *buffer, size_t len)
 	/* Take care of 'guard time' */
 	udelay(SLEEP_DURATION_US);
 	if (rc)
-		return -rc;
+		return rc;
 
 	return 0;
 }
 
-static int tpm_tis_i2c_write_generic(u8 addr, u8 *buffer, size_t len,
+static int tpm_tis_i2c_write_generic(struct udevice *dev, u8 addr,
+				     const u8 *buffer, size_t len,
 				     unsigned int sleep_time_us, u8 max_count)
 {
+	struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
+	struct tpm_chip *chip = dev_get_priv(dev);
 	int rc = 0;
 	int count;
 
+	if (chip->chip_type == SLB9635) {
+		/* Prepare send buffer to include the address */
+		priv->buf[0] = addr;
+		memcpy(&(priv->buf[1]), buffer, len);
+		buffer = priv->buf;
+		len++;
+		addr = 0;
+	}
+
 	for (count = 0; count < max_count; count++) {
-		rc = dm_i2c_write(g_chip.dev, addr, buffer, len);
+		rc = dm_i2c_write(dev, addr, buffer, len);
 		if (rc == 0)
 			break;  /* Success, break to skip sleep */
 		udelay(sleep_time_us);
@@ -125,7 +137,7 @@ static int tpm_tis_i2c_write_generic(u8 addr, u8 *buffer, size_t len,
 	/* take care of 'guard time' */
 	udelay(sleep_time_us);
 	if (rc)
-		return -rc;
+		return rc;
 
 	return 0;
 }
@@ -146,30 +158,33 @@ static int tpm_tis_i2c_write_generic(u8 addr, u8 *buffer, size_t len,
  *
  * Return -EIO on error, 0 on success
  */
-static int tpm_tis_i2c_write(u8 addr, u8 *buffer, size_t len)
+static int tpm_tis_i2c_write(struct udevice *dev, u8 addr, const u8 *buffer,
+			     size_t len)
 {
-	return tpm_tis_i2c_write_generic(addr, buffer, len, SLEEP_DURATION_US,
-					 MAX_COUNT);
+	return tpm_tis_i2c_write_generic(dev, addr, buffer, len,
+					 SLEEP_DURATION_US, MAX_COUNT);
 }
 
 /*
  * This function is needed especially for the cleanup situation after
  * sending TPM_READY
  */
-static int tpm_tis_i2c_write_long(u8 addr, u8 *buffer, size_t len)
+static int tpm_tis_i2c_write_long(struct udevice *dev, u8 addr, u8 *buffer,
+				  size_t len)
 {
-	return tpm_tis_i2c_write_generic(addr, buffer, len,
+	return tpm_tis_i2c_write_generic(dev, addr, buffer, len,
 					 SLEEP_DURATION_LONG_US,
 					 MAX_COUNT_LONG);
 }
 
-static int tpm_tis_i2c_check_locality(struct tpm_chip *chip, int loc)
+static int tpm_tis_i2c_check_locality(struct udevice *dev, int loc)
 {
 	const u8 mask = TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID;
+	struct tpm_chip *chip = dev_get_priv(dev);
 	u8 buf;
 	int rc;
 
-	rc = tpm_tis_i2c_read(TPM_ACCESS(loc), &buf, 1);
+	rc = tpm_tis_i2c_read(dev, TPM_ACCESS(loc), &buf, 1);
 	if (rc < 0)
 		return rc;
 
@@ -178,75 +193,96 @@ static int tpm_tis_i2c_check_locality(struct tpm_chip *chip, int loc)
 		return loc;
 	}
 
-	return -1;
+	return -ENOENT;
 }
 
-static void tpm_tis_i2c_release_locality(struct tpm_chip *chip, int loc,
+static void tpm_tis_i2c_release_locality(struct udevice *dev, int loc,
 					 int force)
 {
 	const u8 mask = TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID;
 	u8 buf;
 
-	if (tpm_tis_i2c_read(TPM_ACCESS(loc), &buf, 1) < 0)
+	if (tpm_tis_i2c_read(dev, TPM_ACCESS(loc), &buf, 1) < 0)
 		return;
 
 	if (force || (buf & mask) == mask) {
 		buf = TPM_ACCESS_ACTIVE_LOCALITY;
-		tpm_tis_i2c_write(TPM_ACCESS(loc), &buf, 1);
+		tpm_tis_i2c_write(dev, TPM_ACCESS(loc), &buf, 1);
 	}
 }
 
-static int tpm_tis_i2c_request_locality(struct tpm_chip *chip, int loc)
+static int tpm_tis_i2c_request_locality(struct udevice *dev, int loc)
 {
+	struct tpm_chip *chip = dev_get_priv(dev);
 	unsigned long start, stop;
 	u8 buf = TPM_ACCESS_REQUEST_USE;
 	int rc;
 
-	if (tpm_tis_i2c_check_locality(chip, loc) >= 0)
+	rc = tpm_tis_i2c_check_locality(dev, loc);
+	if (rc >= 0) {
+		debug("%s: Already have locality\n", __func__);
 		return loc;  /* We already have the locality */
+	} else if (rc != -ENOENT) {
+		debug("%s: Failed to get locality: %d\n", __func__, rc);
+		return rc;
+	}
 
-	rc = tpm_tis_i2c_write(TPM_ACCESS(loc), &buf, 1);
-	if (rc)
+	rc = tpm_tis_i2c_write(dev, TPM_ACCESS(loc), &buf, 1);
+	if (rc) {
+		debug("%s: Failed to write to TPM: %d\n", __func__, rc);
 		return rc;
+	}
 
 	/* Wait for burstcount */
 	start = get_timer(0);
 	stop = chip->timeout_a;
 	do {
-		if (tpm_tis_i2c_check_locality(chip, loc) >= 0)
+		rc = tpm_tis_i2c_check_locality(dev, loc);
+		if (rc >= 0) {
+			debug("%s: Have locality\n", __func__);
 			return loc;
+		} else if (rc != -ENOENT) {
+			debug("%s: Failed to get locality: %d\n", __func__, rc);
+			return rc;
+		}
 		mdelay(TPM_TIMEOUT_MS);
 	} while (get_timer(start) < stop);
+	debug("%s: Timeout getting locality: %d\n", __func__, rc);
 
-	return -1;
+	return rc;
 }
 
-static u8 tpm_tis_i2c_status(struct tpm_chip *chip)
+static u8 tpm_tis_i2c_status(struct udevice *dev)
 {
+	struct tpm_chip *chip = dev_get_priv(dev);
 	/* NOTE: Since i2c read may fail, return 0 in this case --> time-out */
 	u8 buf;
 
-	if (tpm_tis_i2c_read(TPM_STS(chip->locality), &buf, 1) < 0)
+	if (tpm_tis_i2c_read(dev, TPM_STS(chip->locality), &buf, 1) < 0)
 		return 0;
 	else
 		return buf;
 }
 
-static void tpm_tis_i2c_ready(struct tpm_chip *chip)
+static int tpm_tis_i2c_ready(struct udevice *dev)
 {
+	struct tpm_chip *chip = dev_get_priv(dev);
 	int rc;
 
 	/* This causes the current command to be aborted */
 	u8 buf = TPM_STS_COMMAND_READY;
 
 	debug("%s\n", __func__);
-	rc = tpm_tis_i2c_write_long(TPM_STS(chip->locality), &buf, 1);
+	rc = tpm_tis_i2c_write_long(dev, TPM_STS(chip->locality), &buf, 1);
 	if (rc)
 		debug("%s: rc=%d\n", __func__, rc);
+
+	return rc;
 }
 
-static ssize_t tpm_tis_i2c_get_burstcount(struct tpm_chip *chip)
+static ssize_t tpm_tis_i2c_get_burstcount(struct udevice *dev)
 {
+	struct tpm_chip *chip = dev_get_priv(dev);
 	unsigned long start, stop;
 	ssize_t burstcnt;
 	u8 addr, buf[3];
@@ -258,7 +294,7 @@ static ssize_t tpm_tis_i2c_get_burstcount(struct tpm_chip *chip)
 	do {
 		/* Note: STS is little endian */
 		addr = TPM_STS(chip->locality) + 1;
-		if (tpm_tis_i2c_read(addr, buf, 3) < 0)
+		if (tpm_tis_i2c_read(dev, addr, buf, 3) < 0)
 			burstcnt = 0;
 		else
 			burstcnt = (buf[2] << 16) + (buf[1] << 8) + buf[0];
@@ -271,13 +307,13 @@ static ssize_t tpm_tis_i2c_get_burstcount(struct tpm_chip *chip)
 	return -EBUSY;
 }
 
-static int tpm_tis_i2c_wait_for_stat(struct tpm_chip *chip, u8 mask,
+static int tpm_tis_i2c_wait_for_stat(struct udevice *dev, u8 mask,
 				     unsigned long timeout, int *status)
 {
 	unsigned long start, stop;
 
 	/* Check current status */
-	*status = tpm_tis_i2c_status(chip);
+	*status = tpm_tis_i2c_status(dev);
 	if ((*status & mask) == mask)
 		return 0;
 
@@ -285,22 +321,23 @@ static int tpm_tis_i2c_wait_for_stat(struct tpm_chip *chip, u8 mask,
 	stop = timeout;
 	do {
 		mdelay(TPM_TIMEOUT_MS);
-		*status = tpm_tis_i2c_status(chip);
+		*status = tpm_tis_i2c_status(dev);
 		if ((*status & mask) == mask)
 			return 0;
 	} while (get_timer(start) < stop);
 
-	return -ETIME;
+	return -ETIMEDOUT;
 }
 
-static int tpm_tis_i2c_recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
+static int tpm_tis_i2c_recv_data(struct udevice *dev, u8 *buf, size_t count)
 {
+	struct tpm_chip *chip = dev_get_priv(dev);
 	size_t size = 0;
 	ssize_t burstcnt;
 	int rc;
 
 	while (size < count) {
-		burstcnt = tpm_tis_i2c_get_burstcount(chip);
+		burstcnt = tpm_tis_i2c_get_burstcount(dev);
 
 		/* burstcount < 0 -> tpm is busy */
 		if (burstcnt < 0)
@@ -310,8 +347,8 @@ static int tpm_tis_i2c_recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
 		if (burstcnt > (count - size))
 			burstcnt = count - size;
 
-		rc = tpm_tis_i2c_read(TPM_DATA_FIFO(chip->locality),
-				&(buf[size]), burstcnt);
+		rc = tpm_tis_i2c_read(dev, TPM_DATA_FIFO(chip->locality),
+				      &(buf[size]), burstcnt);
 		if (rc == 0)
 			size += burstcnt;
 	}
@@ -319,61 +356,58 @@ static int tpm_tis_i2c_recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
 	return size;
 }
 
-static int tpm_tis_i2c_recv(struct tpm_chip *chip, u8 *buf, size_t count)
+static int tpm_tis_i2c_recv(struct udevice *dev, u8 *buf, size_t count)
 {
+	struct tpm_chip *chip = dev_get_priv(dev);
 	int size = 0;
 	int expected, status;
+	int rc;
 
-	if (count < TPM_HEADER_SIZE) {
-		size = -EIO;
-		goto out;
-	}
+	status = tpm_tis_i2c_status(dev);
+	if (status == TPM_STS_COMMAND_READY)
+		return -EINTR;
+	if ((status & (TPM_STS_DATA_AVAIL | TPM_STS_VALID)) !=
+	    (TPM_STS_DATA_AVAIL | TPM_STS_VALID))
+		return -EAGAIN;
+
+	debug("...got it;\n");
 
 	/* Read first 10 bytes, including tag, paramsize, and result */
-	size = tpm_tis_i2c_recv_data(chip, buf, TPM_HEADER_SIZE);
+	size = tpm_tis_i2c_recv_data(dev, buf, TPM_HEADER_SIZE);
 	if (size < TPM_HEADER_SIZE) {
-		error("Unable to read header\n");
-		goto out;
+		debug("Unable to read header\n");
+		return size < 0 ? size : -EIO;
 	}
 
 	expected = get_unaligned_be32(buf + TPM_RSP_SIZE_BYTE);
 	if ((size_t)expected > count) {
-		error("Error size=%x, expected=%x, count=%x\n", size, expected,
+		debug("Error size=%x, expected=%x, count=%x\n", size, expected,
 		      count);
-		size = -EIO;
-		goto out;
+		return -ENOSPC;
 	}
 
-	size += tpm_tis_i2c_recv_data(chip, &buf[TPM_HEADER_SIZE],
+	size += tpm_tis_i2c_recv_data(dev, &buf[TPM_HEADER_SIZE],
 				      expected - TPM_HEADER_SIZE);
 	if (size < expected) {
-		error("Unable to read remainder of result\n");
-		size = -ETIME;
-		goto out;
+		debug("Unable to read remainder of result\n");
+		return -ETIMEDOUT;
 	}
 
-	tpm_tis_i2c_wait_for_stat(chip, TPM_STS_VALID, chip->timeout_c,
-				  &status);
+	rc = tpm_tis_i2c_wait_for_stat(dev, TPM_STS_VALID, chip->timeout_c,
+				       &status);
+	if (rc)
+		return rc;
 	if (status & TPM_STS_DATA_AVAIL) {  /* Retry? */
-		error("Error left over data\n");
-		size = -EIO;
-		goto out;
+		debug("Error left over data\n");
+		return -EIO;
 	}
 
-out:
-	tpm_tis_i2c_ready(chip);
-	/*
-	 * The TPM needs some time to clean up here,
-	 * so we sleep rather than keeping the bus busy
-	 */
-	mdelay(2);
-	tpm_tis_i2c_release_locality(chip, chip->locality, 0);
-
 	return size;
 }
 
-static int tpm_tis_i2c_send(struct tpm_chip *chip, u8 *buf, size_t len)
+static int tpm_tis_i2c_send(struct udevice *dev, const u8 *buf, size_t len)
 {
+	struct tpm_chip *chip = dev_get_priv(dev);
 	int rc, status;
 	size_t burstcnt;
 	size_t count = 0;
@@ -384,20 +418,21 @@ static int tpm_tis_i2c_send(struct tpm_chip *chip, u8 *buf, size_t len)
 	if (len > TPM_DEV_BUFSIZE)
 		return -E2BIG;  /* Command is too long for our tpm, sorry */
 
-	if (tpm_tis_i2c_request_locality(chip, 0) < 0)
+	if (tpm_tis_i2c_request_locality(dev, 0) < 0)
 		return -EBUSY;
 
-	status = tpm_tis_i2c_status(chip);
+	status = tpm_tis_i2c_status(dev);
 	if ((status & TPM_STS_COMMAND_READY) == 0) {
-		tpm_tis_i2c_ready(chip);
-		if (tpm_tis_i2c_wait_for_stat(chip, TPM_STS_COMMAND_READY,
-					      chip->timeout_b, &status) < 0) {
-			rc = -ETIME;
-			goto out_err;
-		}
+		rc = tpm_tis_i2c_ready(dev);
+		if (rc)
+			return rc;
+		rc = tpm_tis_i2c_wait_for_stat(dev, TPM_STS_COMMAND_READY,
+					       chip->timeout_b, &status);
+		if (rc)
+			return rc;
 	}
 
-	burstcnt = tpm_tis_i2c_get_burstcount(chip);
+	burstcnt = tpm_tis_i2c_get_burstcount(dev);
 
 	/* burstcount < 0 -> tpm is busy */
 	if (burstcnt < 0)
@@ -409,98 +444,79 @@ static int tpm_tis_i2c_send(struct tpm_chip *chip, u8 *buf, size_t len)
 			burstcnt = len - count;
 
 #ifdef CONFIG_TPM_TIS_I2C_BURST_LIMITATION
-		if (retry && burstcnt > CONFIG_TPM_TIS_I2C_BURST_LIMITATION)
-			burstcnt = CONFIG_TPM_TIS_I2C_BURST_LIMITATION;
+		if (retry && burstcnt > CONFIG_TPM_TIS_I2C_BURST_LIMITATION_LEN)
+			burstcnt = CONFIG_TPM_TIS_I2C_BURST_LIMITATION_LEN;
 #endif /* CONFIG_TPM_TIS_I2C_BURST_LIMITATION */
 
-		rc = tpm_tis_i2c_write(TPM_DATA_FIFO(chip->locality),
-				&(buf[count]), burstcnt);
+		rc = tpm_tis_i2c_write(dev, TPM_DATA_FIFO(chip->locality),
+				       &(buf[count]), burstcnt);
 		if (rc == 0)
 			count += burstcnt;
 		else {
 			debug("%s: error\n", __func__);
-			if (retry++ > 10) {
-				rc = -EIO;
-				goto out_err;
-			}
-			rc = tpm_tis_i2c_wait_for_stat(chip, TPM_STS_VALID,
+			if (retry++ > 10)
+				return -EIO;
+			rc = tpm_tis_i2c_wait_for_stat(dev, TPM_STS_VALID,
 						       chip->timeout_c,
 						       &status);
 			if (rc)
-				goto out_err;
+				return rc;
 
-			if ((status & TPM_STS_DATA_EXPECT) == 0) {
-				rc = -EIO;
-				goto out_err;
-			}
+			if ((status & TPM_STS_DATA_EXPECT) == 0)
+				return -EIO;
 		}
 	}
 
 	/* Go and do it */
-	tpm_tis_i2c_write(TPM_STS(chip->locality), &sts, 1);
-	debug("done\n");
+	rc = tpm_tis_i2c_write(dev, TPM_STS(chip->locality), &sts, 1);
+	if (rc < 0)
+		return rc;
+	debug("%s: done, rc=%d\n", __func__, rc);
 
 	return len;
+}
+
+static int tpm_tis_i2c_cleanup(struct udevice *dev)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
 
-out_err:
-	debug("%s: out_err\n", __func__);
-	tpm_tis_i2c_ready(chip);
+	tpm_tis_i2c_ready(dev);
 	/*
 	 * The TPM needs some time to clean up here,
 	 * so we sleep rather than keeping the bus busy
 	 */
 	mdelay(2);
-	tpm_tis_i2c_release_locality(chip, chip->locality, 0);
+	tpm_tis_i2c_release_locality(dev, chip->locality, 0);
 
-	return rc;
-}
-
-static enum i2c_chip_type tpm_tis_i2c_chip_type(void)
-{
-#if CONFIG_IS_ENABLED(OF_CONTROL)
-	const void *blob = gd->fdt_blob;
-
-	if (fdtdec_next_compatible(blob, 0, COMPAT_INFINEON_SLB9645_TPM) >= 0)
-		return SLB9645;
-
-	if (fdtdec_next_compatible(blob, 0, COMPAT_INFINEON_SLB9635_TPM) >= 0)
-		return SLB9635;
-#endif
-	return UNKNOWN;
+	return 0;
 }
 
 static int tpm_tis_i2c_init(struct udevice *dev)
 {
-	struct tpm_chip *chip = &g_chip;
+	struct tpm_chip *chip = dev_get_priv(dev);
 	u32 vendor;
 	u32 expected_did_vid;
+	int rc;
 
-	g_chip.dev = dev;
-	g_chip.chip_type = tpm_tis_i2c_chip_type();
 	chip->is_open = 1;
 
-	/* Disable interrupts (not supported) */
-	chip->irq = 0;
-
 	/* Default timeouts - these could move to the device tree */
 	chip->timeout_a = TIS_SHORT_TIMEOUT_MS;
 	chip->timeout_b = TIS_LONG_TIMEOUT_MS;
 	chip->timeout_c = TIS_SHORT_TIMEOUT_MS;
 	chip->timeout_d = TIS_SHORT_TIMEOUT_MS;
-	chip->req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID;
-	chip->req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID;
-	chip->req_canceled = TPM_STS_COMMAND_READY;
 
-	if (tpm_tis_i2c_request_locality(chip, 0) < 0)
-		return  -ENODEV;
+	rc = tpm_tis_i2c_request_locality(dev, 0);
+	if (rc < 0)
+		return rc;
 
 	/* Read four bytes from DID_VID register */
-	if (tpm_tis_i2c_read(TPM_DID_VID(0), (uchar *)&vendor, 4) < 0) {
-		tpm_tis_i2c_release_locality(chip, 0, 1);
+	if (tpm_tis_i2c_read(dev, TPM_DID_VID(0), (uchar *)&vendor, 4) < 0) {
+		tpm_tis_i2c_release_locality(dev, 0, 1);
 		return -EIO;
 	}
 
-	if (g_chip.chip_type == SLB9635) {
+	if (chip->chip_type == SLB9635) {
 		vendor = be32_to_cpu(vendor);
 		expected_did_vid = TPM_TIS_I2C_DID_VID_9635;
 	} else {
@@ -508,13 +524,14 @@ static int tpm_tis_i2c_init(struct udevice *dev)
 		expected_did_vid = TPM_TIS_I2C_DID_VID_9645;
 	}
 
-	if (g_chip.chip_type != UNKNOWN && vendor != expected_did_vid) {
+	if (chip->chip_type != UNKNOWN && vendor != expected_did_vid) {
 		error("Vendor id did not match! ID was %08x\n", vendor);
 		return -ENODEV;
 	}
 
+	chip->vend_dev = vendor;
 	debug("1.2 TPM (chip type %s device-id 0x%X)\n",
-	      chip_name[g_chip.chip_type], vendor >> 16);
+	      chip_name[chip->chip_type], vendor >> 16);
 
 	/*
 	 * A timeout query to TPM can be placed here.
@@ -524,225 +541,83 @@ static int tpm_tis_i2c_init(struct udevice *dev)
 	return 0;
 }
 
-/* Returns max number of milliseconds to wait */
-static unsigned long tpm_tis_i2c_calc_ordinal_duration(struct tpm_chip *chip,
-						       u32 ordinal)
-{
-	int duration_idx = TPM_UNDEFINED;
-	int duration = 0;
-
-	if (ordinal < TPM_MAX_ORDINAL) {
-		duration_idx = tpm_ordinal_duration[ordinal];
-	} else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
-			TPM_MAX_PROTECTED_ORDINAL) {
-		duration_idx = tpm_protected_ordinal_duration[
-				ordinal & TPM_PROTECTED_ORDINAL_MASK];
-	}
-
-	if (duration_idx != TPM_UNDEFINED)
-		duration = chip->duration[duration_idx];
-
-	if (duration <= 0)
-		return 2 * 60 * HZ; /* Two minutes timeout */
-	else
-		return duration;
-}
-
-static ssize_t tpm_tis_i2c_transmit(const unsigned char *buf, size_t bufsiz)
+static int tpm_tis_i2c_open(struct udevice *dev)
 {
+	struct tpm_chip *chip = dev_get_priv(dev);
 	int rc;
-	u32 count, ordinal;
-	unsigned long start, stop;
-
-	struct tpm_chip *chip = &g_chip;
-
-	/* switch endianess: big->little */
-	count = get_unaligned_be32(buf + TPM_CMD_COUNT_BYTE);
-	ordinal = get_unaligned_be32(buf + TPM_CMD_ORDINAL_BYTE);
 
-	if (count == 0) {
-		error("no data\n");
-		return -ENODATA;
-	}
-	if (count > bufsiz) {
-		error("invalid count value %x %zx\n", count, bufsiz);
-		return -E2BIG;
-	}
-
-	debug("Calling send\n");
-	rc = tpm_tis_i2c_send(chip, (u8 *)buf, count);
-	debug("   ... done calling send\n");
-	if (rc < 0) {
-		error("tpm_transmit: tpm_send: error %d\n", rc);
-		goto out;
-	}
-
-	if (chip->irq)
-		goto out_recv;
-
-	start = get_timer(0);
-	stop = tpm_tis_i2c_calc_ordinal_duration(chip, ordinal);
-	do {
-		debug("waiting for status... %ld %ld\n", start, stop);
-		u8 status = tpm_tis_i2c_status(chip);
-		if ((status & chip->req_complete_mask) ==
-		    chip->req_complete_val) {
-			debug("...got it;\n");
-			goto out_recv;
-		}
-
-		if (status == chip->req_canceled) {
-			error("Operation Canceled\n");
-			rc = -ECANCELED;
-			goto out;
-		}
-		mdelay(TPM_TIMEOUT_MS);
-	} while (get_timer(start) < stop);
-
-	tpm_tis_i2c_ready(chip);
-	error("Operation Timed out\n");
-	rc = -ETIME;
-	goto out;
-
-out_recv:
-	debug("out_recv: reading response...\n");
-	rc = tpm_tis_i2c_recv(chip, (u8 *)buf, TPM_BUFSIZE);
+	debug("%s: start\n", __func__);
+	if (chip->is_open)
+		return -EBUSY;
+	rc = tpm_tis_i2c_init(dev);
 	if (rc < 0)
-		error("tpm_transmit: tpm_recv: error %d\n", rc);
+		chip->is_open = 0;
 
-out:
 	return rc;
 }
 
-/**
- * Decode TPM configuration.
- *
- * @param dev	Returns a configuration of TPM device
- * @return 0 if ok, -1 on error
- */
-static int tpm_tis_i2c_decode_config(struct tpm_chip *chip)
+static int tpm_tis_i2c_close(struct udevice *dev)
 {
-	const void *blob = gd->fdt_blob;
-	struct udevice *bus;
-	int chip_addr;
-	int parent;
-	int node;
-	int ret;
-
-	node = fdtdec_next_compatible(blob, 0, COMPAT_INFINEON_SLB9635_TPM);
-	if (node < 0) {
-		node = fdtdec_next_compatible(blob, 0,
-				COMPAT_INFINEON_SLB9645_TPM);
-	}
-	if (node < 0) {
-		debug("%s: Node not found\n", __func__);
-		return -1;
-	}
-	parent = fdt_parent_offset(blob, node);
-	if (parent < 0) {
-		debug("%s: Cannot find node parent\n", __func__);
-		return -1;
-	}
+	struct tpm_chip *chip = dev_get_priv(dev);
 
-	/*
-	 * TODO(sjg@chromium.org): Remove this when driver model supports
-	 * TPMs
-	 */
-	ret = uclass_get_device_by_of_offset(UCLASS_I2C, parent, &bus);
-	if (ret) {
-		debug("Cannot find bus for node '%s: ret=%d'\n",
-		      fdt_get_name(blob, parent, NULL), ret);
-		return ret;
-	}
-
-	chip_addr = fdtdec_get_int(blob, node, "reg", -1);
-	if (chip_addr == -1) {
-		debug("Cannot find reg property for node '%s: ret=%d'\n",
-		      fdt_get_name(blob, node, NULL), ret);
-		return ret;
-	}
-	/*
-	 * TODO(sjg@chromium.org): Older TPMs will need to use the older method
-	 * in tpm_tis_i2c_read() so the offset length needs to be 0 here.
-	 */
-	ret = i2c_get_chip(bus, chip_addr, 1, &chip->dev);
-	if (ret) {
-		debug("Cannot find device for node '%s: ret=%d'\n",
-		      fdt_get_name(blob, node, NULL), ret);
-		return ret;
+	if (chip->is_open) {
+		tpm_tis_i2c_release_locality(dev, chip->locality, 1);
+		chip->is_open = 0;
+		chip->vend_dev = 0;
 	}
 
 	return 0;
 }
 
-int tis_init(void)
+static int tpm_tis_get_desc(struct udevice *dev, char *buf, int size)
 {
-	if (g_chip.inited)
-		return 0;
-
-	if (tpm_tis_i2c_decode_config(&g_chip))
-		return -1;
-
-	debug("%s: done\n", __func__);
+	struct tpm_chip *chip = dev_get_priv(dev);
 
-	g_chip.inited = 1;
+	if (size < 50)
+		return -ENOSPC;
 
-	return 0;
+	return snprintf(buf, size, "1.2 TPM (%s, chip type %s device-id 0x%x)",
+			chip->is_open ? "open" : "closed",
+			chip_name[chip->chip_type],
+			chip->vend_dev >> 16);
 }
 
-int tis_open(void)
+static int tpm_tis_i2c_probe(struct udevice *dev)
 {
-	int rc;
-
-	if (!g_chip.inited)
-		return -1;
-
-	debug("%s: start\n", __func__);
-	if (g_chip.is_open)
-		return -EBUSY;
-	rc = tpm_tis_i2c_init(g_chip.dev);
-	if (rc < 0)
-		g_chip.is_open = 0;
-
-	return rc;
-}
+	struct tpm_chip_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct tpm_chip *chip = dev_get_priv(dev);
 
-int tis_close(void)
-{
-	if (!g_chip.inited)
-		return -1;
+	chip->chip_type = dev_get_driver_data(dev);
 
-	if (g_chip.is_open) {
-		tpm_tis_i2c_release_locality(&g_chip, g_chip.locality, 1);
-		g_chip.is_open = 0;
-	}
+	/* TODO: These need to be checked and tuned */
+	uc_priv->duration_ms[TPM_SHORT] = TIS_SHORT_TIMEOUT_MS;
+	uc_priv->duration_ms[TPM_MEDIUM] = TIS_LONG_TIMEOUT_MS;
+	uc_priv->duration_ms[TPM_LONG] = TIS_LONG_TIMEOUT_MS;
+	uc_priv->retry_time_ms = TPM_TIMEOUT_MS;
 
 	return 0;
 }
 
-int tis_sendrecv(const uint8_t *sendbuf, size_t sbuf_size,
-		uint8_t *recvbuf, size_t *rbuf_len)
-{
-	int len;
-	uint8_t buf[4096];
-
-	if (!g_chip.inited)
-		return -1;
-
-	if (sizeof(buf) < sbuf_size)
-		return -1;
-
-	memcpy(buf, sendbuf, sbuf_size);
-
-	len = tpm_tis_i2c_transmit(buf, sbuf_size);
-
-	if (len < 10) {
-		*rbuf_len = 0;
-		return -1;
-	}
+static const struct tpm_ops tpm_tis_i2c_ops = {
+	.open		= tpm_tis_i2c_open,
+	.close		= tpm_tis_i2c_close,
+	.get_desc	= tpm_tis_get_desc,
+	.send		= tpm_tis_i2c_send,
+	.recv		= tpm_tis_i2c_recv,
+	.cleanup	= tpm_tis_i2c_cleanup,
+};
 
-	memcpy(recvbuf, buf, len);
-	*rbuf_len = len;
+static const struct udevice_id tpm_tis_i2c_ids[] = {
+	{ .compatible = "infineon,slb9635tt", .data = SLB9635 },
+	{ .compatible = "infineon,slb9645tt", .data = SLB9645 },
+	{ }
+};
 
-	return 0;
-}
+U_BOOT_DRIVER(tpm_tis_i2c) = {
+	.name   = "tpm_tis_i2c",
+	.id     = UCLASS_TPM,
+	.of_match = tpm_tis_i2c_ids,
+	.ops    = &tpm_tis_i2c_ops,
+	.probe	= tpm_tis_i2c_probe,
+	.priv_auto_alloc_size = sizeof(struct tpm_chip),
+};
diff --git a/drivers/tpm/tpm_tis_i2c.h b/drivers/tpm/tpm_tis_i2c.h
index 02cc2eba42..3b510d101e 100644
--- a/drivers/tpm/tpm_tis_i2c.h
+++ b/drivers/tpm/tpm_tis_i2c.h
@@ -37,9 +37,6 @@ enum tpm_timeout {
 #define TPM_RSP_SIZE_BYTE	2
 #define TPM_RSP_RC_BYTE		6
 
-/* Max buffer size supported by our tpm */
-#define TPM_DEV_BUFSIZE		1260
-
 enum i2c_chip_type {
 	SLB9635,
 	SLB9645,
@@ -47,17 +44,10 @@ enum i2c_chip_type {
 };
 
 struct tpm_chip {
-	bool inited;
 	int is_open;
-	u8 req_complete_mask;
-	u8 req_complete_val;
-	u8 req_canceled;
-	int irq;
 	int locality;
+	u32 vend_dev;
 	unsigned long timeout_a, timeout_b, timeout_c, timeout_d;  /* msec */
-	unsigned long duration[3];  /* msec */
-	struct udevice *dev;
-	u8 buf[TPM_DEV_BUFSIZE + sizeof(u8)];  /* Max buffer size + addr */
 	enum i2c_chip_type chip_type;
 };
 
@@ -129,8 +119,6 @@ struct tpm_cmd_t {
  */
 #define MAX_COUNT_LONG		50
 
-#define TPM_HEADER_SIZE		10
-
 enum tis_access {
 	TPM_ACCESS_VALID		= 0x80,
 	TPM_ACCESS_ACTIVE_LOCALITY	= 0x20,
@@ -155,10 +143,4 @@ enum tis_status {
 #define	TPM_DATA_FIFO(l)		(0x0005 | ((l) << 4))
 #define	TPM_DID_VID(l)			(0x0006 | ((l) << 4))
 
-/* Extended error numbers from linux (see errno.h) */
-#define ECANCELED	125	/* Operation Canceled */
-
-/* Timer frequency. Corresponds to msec timer resolution */
-#define HZ		1000
-
 #endif