[PATCH linux dev-5.15 0/7] Add tpm i2c ptp driver

[PATCH linux dev-5.15 0/7] Add tpm i2c ptp driver

[Eddie James]

This is the latest (v19) series that's been sent upstream. There is need
for it on OpenBMC systems now and it's working well, so I'm sending it for
inclusion in dev-5.15.
I also added the TPM to the two P10 IBM systems devicetrees.

Amir Mizinski (5):
  tpm_tis: Fix expected bit handling
  tpm: tpm_tis: Rewrite "tpm_tis_req_canceled()"
  tpm: tpm_tis: Verify TPM_STS register is valid after locality request
  tpm: tpm_tis: Add tpm_tis_i2c driver
  tpm: Add YAML schema for TPM TIS I2C options

Eddie James (2):
  ARM: dts: aspeed: Rainier: Add TPM device
  ARM: dts: aspeed: Everest: Add TPM device

 .../bindings/security/tpm/tpm-tis-i2c.yaml    |  52 ++++
 arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts  |   5 +
 arch/arm/boot/dts/aspeed-bmc-ibm-rainier.dts  |   5 +
 drivers/char/tpm/Kconfig                      |  12 +
 drivers/char/tpm/Makefile                     |   1 +
 drivers/char/tpm/tpm_tis_core.c               |  72 +++--
 drivers/char/tpm/tpm_tis_i2c.c                | 263 ++++++++++++++++++
 7 files changed, 371 insertions(+), 39 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/security/tpm/tpm-tis-i2c.yaml
 create mode 100644 drivers/char/tpm/tpm_tis_i2c.c

-- 
2.27.0

[PATCH linux dev-5.15 1/7] tpm_tis: Fix expected bit handling

[Eddie James]

From: Amir Mizinski <amirmizi6@gmail.com>

Currently, the driver polls the TPM_STS.stsValid field until TRUE; then it
reads TPM_STS register again to verify only that TPM_STS.expect field is
FALSE (i.e., it ignores TPM_STS.stsValid).
Since TPM_STS.stsValid represents the TPM_STS.expect validity, a check of
only one of these fields is wrong. Fix this condition so that both fields
are checked in the same TPM_STS register read.

Modify the signature of wait_for_tpm_stat() to tpm_tis_wait_for_stat(),
adding an additional "expected" parameter to its call.
tpm_tis_wait_for_stat() is now polling the TPM_STS with a mask and waits
for the value in "expected". This modification adds the ability to check if
certain TPM_STS bits have been cleared.
For example, use the new parameter to check in status that TPM_STS_VALID
is set and also that TPM_STS_EXPECT is zeroed. This prevents a racy
check.

Suggested-by: Benoit Houyere <benoit.houyere@st.com>
Signed-off-by: Amir Mizinski <amirmizi6@gmail.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
---
 drivers/char/tpm/tpm_tis_core.c | 61 +++++++++++++++------------------
 1 file changed, 27 insertions(+), 34 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index b2659a4c4016..adb086b6df7c 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -44,9 +44,9 @@ static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
 	return false;
 }
 
-static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask,
-		unsigned long timeout, wait_queue_head_t *queue,
-		bool check_cancel)
+static int tpm_tis_wait_for_stat(struct tpm_chip *chip, u8 mask, u8 expected,
+				 unsigned long timeout,
+				 wait_queue_head_t *queue, bool check_cancel)
 {
 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 	unsigned long stop;
@@ -56,7 +56,7 @@ static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask,
 
 	/* check current status */
 	status = chip->ops->status(chip);
-	if ((status & mask) == mask)
+	if ((status & mask) == expected)
 		return 0;
 
 	stop = jiffies + timeout;
@@ -84,7 +84,7 @@ static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask,
 			usleep_range(priv->timeout_min,
 				     priv->timeout_max);
 			status = chip->ops->status(chip);
-			if ((status & mask) == mask)
+			if ((status & mask) == expected)
 				return 0;
 		} while (time_before(jiffies, stop));
 	}
@@ -260,10 +260,11 @@ static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
 	int size = 0, burstcnt, rc;
 
 	while (size < count) {
-		rc = wait_for_tpm_stat(chip,
-				 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
-				 chip->timeout_c,
-				 &priv->read_queue, true);
+		rc = tpm_tis_wait_for_stat(chip,
+					   TPM_STS_DATA_AVAIL | TPM_STS_VALID,
+					   TPM_STS_DATA_AVAIL | TPM_STS_VALID,
+					   chip->timeout_c, &priv->read_queue,
+					   true);
 		if (rc < 0)
 			return rc;
 		burstcnt = get_burstcount(chip);
@@ -316,8 +317,9 @@ static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
 		goto out;
 	}
 
-	if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
-				&priv->int_queue, false) < 0) {
+	if (tpm_tis_wait_for_stat(chip, TPM_STS_VALID, TPM_STS_VALID,
+				  chip->timeout_c, &priv->int_queue,
+				  false) < 0) {
 		size = -ETIME;
 		goto out;
 	}
@@ -343,14 +345,14 @@ 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_WORKAROUND;
 
 	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) {
+		if (tpm_tis_wait_for_stat(chip, TPM_STS_COMMAND_READY,
+					  TPM_STS_COMMAND_READY,
+					  chip->timeout_b, &priv->int_queue,
+					  false) < 0) {
 			rc = -ETIME;
 			goto out_err;
 		}
@@ -370,34 +372,24 @@ static int tpm_tis_send_data(struct tpm_chip *chip, const u8 *buf, size_t len)
 			goto out_err;
 
 		count += burstcnt;
-
-		if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
-					&priv->int_queue, false) < 0) {
+		if (tpm_tis_wait_for_stat(chip, TPM_STS_VALID | TPM_STS_DATA_EXPECT,
+					  TPM_STS_VALID | TPM_STS_DATA_EXPECT, chip->timeout_a,
+					  &priv->int_queue, false) < 0) {
 			rc = -ETIME;
 			goto out_err;
 		}
-		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;
-
-	if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
-				&priv->int_queue, false) < 0) {
+	if (tpm_tis_wait_for_stat(chip, TPM_STS_VALID | TPM_STS_DATA_EXPECT,
+				  TPM_STS_VALID, chip->timeout_a,
+				  &priv->int_queue, false) < 0) {
 		rc = -ETIME;
 		goto out_err;
 	}
-	status = tpm_tis_status(chip);
-	if (!itpm && (status & TPM_STS_DATA_EXPECT) != 0) {
-		rc = -EIO;
-		goto out_err;
-	}
 
 	return 0;
 
@@ -452,9 +444,10 @@ static int tpm_tis_send_main(struct tpm_chip *chip, const u8 *buf, size_t len)
 		ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 
 		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) {
+		if (tpm_tis_wait_for_stat(chip,
+					  TPM_STS_DATA_AVAIL | TPM_STS_VALID,
+					  TPM_STS_DATA_AVAIL | TPM_STS_VALID,
+					  dur, &priv->read_queue, false) < 0) {
 			rc = -ETIME;
 			goto out_err;
 		}
-- 
2.27.0

[PATCH linux dev-5.15 2/7] tpm: tpm_tis: Rewrite "tpm_tis_req_canceled()"

[Eddie James]

From: Amir Mizinski <amirmizi6@gmail.com>

tpm_tis_req_canceled() function is used to check if the caller requested
to abort the current operation. It was found that in some cases
tpm_tis_req_canceled() wrongly returned true.
Since a cancel request sets the TPM_STS.commandReady field to TRUE, the
tpm_tis_req_canceled() function should check only the TPM_STS.commandReady
field value.
The case for TPM_VID_WINBOND is wrong and was therefore removed.

Also, the default comparison is wrong. Only cmdReady bit needs to be
compared instead of the full lower status register byte.

Signed-off-by: Amir Mizinski <amirmizi6@gmail.com>
---
 drivers/char/tpm/tpm_tis_core.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index adb086b6df7c..7d6d07625600 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -662,13 +662,10 @@ 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);
+		return (status & TPM_STS_COMMAND_READY) == TPM_STS_COMMAND_READY;
 	}
 }
 
-- 
2.27.0

[PATCH linux dev-5.15 3/7] tpm: tpm_tis: Verify TPM_STS register is valid after locality request

[Eddie James]

From: Amir Mizinski <amirmizi6@gmail.com>

An invalid TPM_STS value could be used when the following two events occur:
TPM does not update TPM_STS register after a locality request (TPM_STS
Initial value = 0xFF), and a TPM_STS register read occurs in the
tpm_tis_status(chip) function call.

In probe_itpm(), a call to tpm_tis_send_data() function is made after a
request_locality() call, and the condition
("if ((status & TPM_STS_COMMAND_READY) == 0)") is checked. At this moment
if the status value is 0xFF, then it is considered, wrongly, in “ready”
state (by checking only one bit). However, at this moment the TPM is, in
fact, in "Idle" state and remains in "Idle" state because
"tpm_tis_ready(chip);" was not executed.
Waiting for the condition TPM_STS.tpmGo == 0, will ensure that the TPM
status register has the correct value.

Suggested-by: Benoit Houyere <benoit.houyere@st.com>
Signed-off-by: Amir Mizinski <amirmizi6@gmail.com>
---
 drivers/char/tpm/tpm_tis_core.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 7d6d07625600..9a38cbaef1c0 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -178,8 +178,12 @@ static int request_locality(struct tpm_chip *chip, int l)
 	} else {
 		/* wait for burstcount */
 		do {
-			if (check_locality(chip, l))
+			if (check_locality(chip, l)) {
+				if (tpm_tis_wait_for_stat(chip, TPM_STS_GO, 0, chip->timeout_c,
+							  &priv->int_queue, false) < 0)
+					return -ETIME;
 				return l;
+			}
 			tpm_msleep(TPM_TIMEOUT);
 		} while (time_before(jiffies, stop));
 	}
-- 
2.27.0

[PATCH linux dev-5.15 4/7] tpm: tpm_tis: Add tpm_tis_i2c driver

[Eddie James]

From: Amir Mizinski <amirmizi6@gmail.com>

I2C support for TPM devices on the TIS interface is currently available
only as a proprietary driver implementation for each TPM vendor.
This patch implements the infrastructure for a TCG-compliant TPM TIS I2C
driver with the functionality required to communicate with a TPM device
over I2C according to the "TCG PC Client PTP Interface Specification"
and "Device Driver Design Principles for TPM 2.0"

References:
[1] "TCG PC Client Platform TPM Profile(PTP) Interface Specification for
TPM 2.0" Version 01.03 Revision 22 at:
https://trustedcomputinggroup.org/resource/pc-client-platform-tpm-profile-ptp-specification/
[2] "TCG PC Client Device Driver Design Principles for TPM 2.0"
Version 1.0 Revision 27 at:
https://trustedcomputinggroup.org/resource/tcg-pc-client-device-driver-design-principles-for-tpm-2-0/

Signed-off-by: Amir Mizinski <amirmizi6@gmail.com>
Tested-by: Eddie James <eajames@linux.ibm.com>
Tested-by: Joel Stanley <joel@jms.id.au>
---
 drivers/char/tpm/Kconfig       |  12 ++
 drivers/char/tpm/Makefile      |   1 +
 drivers/char/tpm/tpm_tis_i2c.c | 263 +++++++++++++++++++++++++++++++++
 3 files changed, 276 insertions(+)
 create mode 100644 drivers/char/tpm/tpm_tis_i2c.c

diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig
index d6ba644f6b00..f07ae63298ec 100644
--- a/drivers/char/tpm/Kconfig
+++ b/drivers/char/tpm/Kconfig
@@ -86,6 +86,18 @@ config TCG_TIS_SYNQUACER
 	  To compile this driver as a module, choose  M here;
 	  the module will be called tpm_tis_synquacer.
 
+config TCG_TIS_I2C
+	tristate "TPM I2C Interface Specification"
+	depends on I2C
+	select CRC_CCITT
+	select TCG_TIS_CORE
+	help
+	  If you have a TPM security chip, compliant with the TCG TPM PTP
+	  (I2C interface) specification and connected to an I2C bus master,
+	  say Yes and it will be accessible from within Linux.
+	  To compile this driver as a module, choose M here;
+	  the module will be called tpm_tis_i2c.
+
 config TCG_TIS_I2C_CR50
 	tristate "TPM Interface Specification 2.0 Interface (I2C - CR50)"
 	depends on I2C
diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
index 66d39ea6bd10..0222b1ddb310 100644
--- a/drivers/char/tpm/Makefile
+++ b/drivers/char/tpm/Makefile
@@ -29,6 +29,7 @@ tpm_tis_spi-$(CONFIG_TCG_TIS_SPI_CR50) += tpm_tis_spi_cr50.o
 
 obj-$(CONFIG_TCG_TIS_I2C_CR50) += tpm_tis_i2c_cr50.o
 
+obj-$(CONFIG_TCG_TIS_I2C) += tpm_tis_i2c.o
 obj-$(CONFIG_TCG_TIS_I2C_ATMEL) += tpm_i2c_atmel.o
 obj-$(CONFIG_TCG_TIS_I2C_INFINEON) += tpm_i2c_infineon.o
 obj-$(CONFIG_TCG_TIS_I2C_NUVOTON) += tpm_i2c_nuvoton.o
diff --git a/drivers/char/tpm/tpm_tis_i2c.c b/drivers/char/tpm/tpm_tis_i2c.c
new file mode 100644
index 000000000000..12984a3be327
--- /dev/null
+++ b/drivers/char/tpm/tpm_tis_i2c.c
@@ -0,0 +1,263 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2014-2021 Nuvoton Technology corporation
+ *
+ * TPM TIS I2C Device Driver Interface for devices that implement the TPM
+ * I2C Interface defined by "TCG PC Client Platform TPM Profile (PTP)
+ * Specification version 01.05 r14" and "TCG PC Client Device Driver
+ * Design Principles version 1.0 r27" for TPM 2.0 at
+ * www.trustedcomputinggroup.org
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/wait.h>
+#include <linux/acpi.h>
+#include <linux/freezer.h>
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+#include <linux/of_irq.h>
+#include <linux/of_gpio.h>
+#include <linux/tpm.h>
+#include "tpm_tis_core.h"
+
+#define TPM_LOC_SEL			0x04
+#define TPM_I2C_INTERFACE_CAPABILITY	0x30
+#define TPM_I2C_DEVICE_ADDRESS		0x38
+#define TPM_DATA_CSUM_ENABLE		0x40
+#define TPM_I2C_DID_VID			0x48
+#define TPM_I2C_RID			0x4C
+
+struct tpm_tis_i2c_phy {
+	struct tpm_tis_data priv;
+	struct i2c_client *i2c_client;
+	u8 *iobuf;
+};
+
+static inline struct tpm_tis_i2c_phy *to_tpm_tis_i2c_phy(struct tpm_tis_data *data)
+{
+	return container_of(data, struct tpm_tis_i2c_phy, priv);
+}
+
+static u8 address_to_register(u32 addr)
+{
+	addr &= 0xFFF;
+
+	switch (addr) {
+		// adapt register addresses that have changed compared to
+		// older TIS versions
+	case TPM_ACCESS(0):
+		return 0x04;
+	case TPM_LOC_SEL:
+		return 0x00;
+	case TPM_DID_VID(0):
+		return 0x48;
+	case TPM_RID(0):
+		return 0x4C;
+	default:
+		return addr;
+	}
+}
+
+static int tpm_tis_i2c_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len, u8 *result)
+{
+	struct tpm_tis_i2c_phy *phy = to_tpm_tis_i2c_phy(data);
+	u8 reg = address_to_register(addr);
+	int ret;
+	int i = 0;
+	struct i2c_msg msgs[] = {
+		{
+			.addr = phy->i2c_client->addr,
+			.len = sizeof(reg),
+			.buf = &reg,
+		},
+		{
+			.addr = phy->i2c_client->addr,
+			.len = len,
+			.buf = result,
+			.flags = I2C_M_RD,
+		},
+	};
+
+	do {
+		ret = i2c_transfer(phy->i2c_client->adapter, msgs,
+				   ARRAY_SIZE(msgs));
+		usleep_range(250, 300); // wait default GUARD_TIME of 250µs
+
+	} while (ret < 0 && i++ < TPM_RETRY);
+
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int tpm_tis_i2c_write_bytes(struct tpm_tis_data *data, u32 addr,
+				   u16 len, const u8 *value)
+{
+	struct tpm_tis_i2c_phy *phy = to_tpm_tis_i2c_phy(data);
+	int ret = 0;
+	int i = 0;
+
+	if (phy->iobuf) {
+		if (len > TPM_BUFSIZE - 1)
+			return -EIO;
+
+		phy->iobuf[0] = address_to_register(addr);
+		memcpy(phy->iobuf + 1, value, len);
+
+		struct i2c_msg msgs[] = {
+			{
+				.addr = phy->i2c_client->addr,
+				.len = len + 1,
+				.buf = phy->iobuf,
+			},
+		};
+
+		do {
+			ret = i2c_transfer(phy->i2c_client->adapter,
+					   msgs, ARRAY_SIZE(msgs));
+			// wait default GUARD_TIME of 250µs
+			usleep_range(250, 300);
+		} while (ret < 0 && i++ < TPM_RETRY);
+	} else {
+		u8 reg = address_to_register(addr);
+
+		struct i2c_msg msgs[] = {
+			{
+				.addr = phy->i2c_client->addr,
+				.len = sizeof(reg),
+				.buf = &reg,
+			},
+			{
+				.addr = phy->i2c_client->addr,
+				.len = len,
+				.buf = (u8 *)value,
+				.flags = I2C_M_NOSTART,
+			},
+		};
+
+		do {
+			ret = i2c_transfer(phy->i2c_client->adapter, msgs,
+					   ARRAY_SIZE(msgs));
+			// wait default GUARD_TIME of 250µs
+			usleep_range(250, 300);
+		} while (ret < 0 && i++ < TPM_RETRY);
+	}
+
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+int tpm_tis_i2c_read16(struct tpm_tis_data *data, u32 addr, u16 *result)
+{
+	__le16 result_le;
+	int rc;
+
+	rc = data->phy_ops->read_bytes(data, addr, sizeof(u16),
+				       (u8 *)&result_le);
+	if (!rc)
+		*result = le16_to_cpu(result_le);
+
+	return rc;
+}
+
+int tpm_tis_i2c_read32(struct tpm_tis_data *data, u32 addr, u32 *result)
+{
+	__le32 result_le;
+	int rc;
+
+	rc = data->phy_ops->read_bytes(data, addr, sizeof(u32),
+				       (u8 *)&result_le);
+	if (!rc)
+		*result = le32_to_cpu(result_le);
+
+	return rc;
+}
+
+int tpm_tis_i2c_write32(struct tpm_tis_data *data, u32 addr, u32 value)
+{
+	__le32 value_le;
+	int rc;
+
+	value_le = cpu_to_le32(value);
+
+	rc = data->phy_ops->write_bytes(data, addr, sizeof(u32),
+					(u8 *)&value_le);
+
+	return rc;
+}
+
+static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
+
+static const struct tpm_tis_phy_ops tpm_i2c_phy_ops = {
+	.read_bytes = tpm_tis_i2c_read_bytes,
+	.write_bytes = tpm_tis_i2c_write_bytes,
+	.read16 = tpm_tis_i2c_read16,
+	.read32 = tpm_tis_i2c_read32,
+	.write32 = tpm_tis_i2c_write32,
+};
+
+static int tpm_tis_i2c_probe(struct i2c_client *dev, const struct i2c_device_id *id)
+{
+	struct tpm_tis_i2c_phy *phy;
+	const u8 loc_init = 0;
+	int rc;
+
+	phy = devm_kzalloc(&dev->dev, sizeof(struct tpm_tis_i2c_phy),
+			   GFP_KERNEL);
+	if (!phy)
+		return -ENOMEM;
+
+	phy->i2c_client = dev;
+
+	if (!i2c_check_functionality(dev->adapter, I2C_FUNC_NOSTART)) {
+		phy->iobuf = devm_kmalloc(&dev->dev, TPM_BUFSIZE, GFP_KERNEL);
+		if (!phy->iobuf)
+			return -ENOMEM;
+	}
+
+	/*select locality 0 (the driver will access only via locality 0)*/
+	rc = tpm_tis_i2c_write_bytes(&phy->priv, TPM_LOC_SEL, 1, &loc_init);
+	if (rc < 0)
+		return rc;
+
+	return tpm_tis_core_init(&dev->dev, &phy->priv, -1, &tpm_i2c_phy_ops,
+					NULL);
+}
+
+static const struct i2c_device_id tpm_tis_i2c_id[] = {
+	{"tpm_tis_i2c", 0},
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, tpm_tis_i2c_id);
+
+static const struct of_device_id of_tis_i2c_match[] = {
+	{ .compatible = "nuvoton,npct75x", },
+	{ .compatible = "tcg,tpm-tis-i2c", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, of_tis_i2c_match);
+
+static struct i2c_driver tpm_tis_i2c_driver = {
+	.driver = {
+		.owner = THIS_MODULE,
+		.name = "tpm_tis_i2c",
+		.pm = &tpm_tis_pm,
+		.of_match_table = of_match_ptr(of_tis_i2c_match),
+	},
+	.probe = tpm_tis_i2c_probe,
+	.id_table = tpm_tis_i2c_id,
+};
+
+module_i2c_driver(tpm_tis_i2c_driver);
+
+MODULE_DESCRIPTION("TPM Driver");
+MODULE_LICENSE("GPL");
-- 
2.27.0

[PATCH linux dev-5.15 5/7] tpm: Add YAML schema for TPM TIS I2C options

[Eddie James]

From: Amir Mizinski <amirmizi6@gmail.com>

Add a YAML schema to support tpm tis i2c related dt-bindings for the I2c
PTP based physical layer.

This patch adds the documentation for corresponding device tree bindings of
I2C based Physical TPM.
Refer to the 'I2C Interface Definition' section in
'TCG PC Client PlatformTPMProfile(PTP) Specification' publication
for specification.

Signed-off-by: Amir Mizinski <amirmizi6@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../bindings/security/tpm/tpm-tis-i2c.yaml    | 52 +++++++++++++++++++
 1 file changed, 52 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/security/tpm/tpm-tis-i2c.yaml

diff --git a/Documentation/devicetree/bindings/security/tpm/tpm-tis-i2c.yaml b/Documentation/devicetree/bindings/security/tpm/tpm-tis-i2c.yaml
new file mode 100644
index 000000000000..217ba8e366c2
--- /dev/null
+++ b/Documentation/devicetree/bindings/security/tpm/tpm-tis-i2c.yaml
@@ -0,0 +1,52 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/security/tpm/tpm-tis-i2c.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: I2C PTP based TPM Device Tree Bindings
+
+maintainers:
+  - Amir Mizinski <amirmizi6@gmail.com>
+
+description:
+  Device Tree Bindings for I2C based Trusted Platform Module(TPM).
+
+properties:
+  compatible:
+    items:
+      - enum:
+          # Nuvoton's Trusted Platform Module (TPM) (NPCT75x)
+          - nuvoton,npct75x
+      - const: tcg,tpm-tis-i2c
+
+  reg:
+    maxItems: 1
+
+  interrupt:
+    maxItems: 1
+
+  crc-checksum:
+    $ref: /schemas/types.yaml#/definitions/flag
+    description:
+      Set this flag to enable CRC checksum.
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      tpm@2e {
+        compatible = "nuvoton,npct75x", "tcg,tpm-tis-i2c";
+        reg = <0x2e>;
+        crc-checksum;
+      };
+    };
+...
-- 
2.27.0

[PATCH linux dev-5.15 6/7] ARM: dts: aspeed: Rainier: Add TPM device

[Eddie James]

Add the Nuvoton NPCT75X.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
 arch/arm/boot/dts/aspeed-bmc-ibm-rainier.dts | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/aspeed-bmc-ibm-rainier.dts b/arch/arm/boot/dts/aspeed-bmc-ibm-rainier.dts
index 866f32cdccea..39e36a69fe46 100644
--- a/arch/arm/boot/dts/aspeed-bmc-ibm-rainier.dts
+++ b/arch/arm/boot/dts/aspeed-bmc-ibm-rainier.dts
@@ -2061,6 +2061,11 @@ eeprom@51 {
 &i2c12 {
 	status = "okay";
 
+	tpm@2e {
+		compatible = "nuvoton,npct75x";
+		reg = <0x2e>;
+	};
+
 	eeprom@50 {
 		compatible = "atmel,24c64";
 		reg = <0x50>;
-- 
2.27.0

[PATCH linux dev-5.15 7/7] ARM: dts: aspeed: Everest: Add TPM device

[Eddie James]

Add the Nuvoton NPCT75X.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
 arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts b/arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts
index f42e2d776ba8..ea7aeaefe85c 100644
--- a/arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts
+++ b/arch/arm/boot/dts/aspeed-bmc-ibm-everest.dts
@@ -1881,6 +1881,11 @@ eeprom@52 {
 
 &i2c12 {
 	status = "okay";
+
+	tpm@2e {
+		compatible = "nuvoton,npct75x";
+		reg = <0x2e>;
+	};
 };
 
 &i2c13 {
-- 
2.27.0