From patchwork Thu Jun 4 13:47:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: amirmizi6@gmail.com X-Patchwork-Id: 199533 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.5 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5C2E7C433DF for ; Thu, 4 Jun 2020 13:48:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3F6BD207DF for ; Thu, 4 Jun 2020 13:48:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728682AbgFDNsZ (ORCPT ); Thu, 4 Jun 2020 09:48:25 -0400 Received: from 212.199.177.27.static.012.net.il ([212.199.177.27]:50223 "EHLO herzl.nuvoton.co.il" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728683AbgFDNsX (ORCPT ); Thu, 4 Jun 2020 09:48:23 -0400 Received: from taln60.nuvoton.co.il (ntil-fw [212.199.177.25]) by herzl.nuvoton.co.il (8.13.8/8.13.8) with ESMTP id 054DltUL011523; Thu, 4 Jun 2020 16:47:55 +0300 Received: by taln60.nuvoton.co.il (Postfix, from userid 10140) id BF1C5639BF; Thu, 4 Jun 2020 16:47:55 +0300 (IDT) From: amirmizi6@gmail.com To: Eyal.Cohen@nuvoton.com, jarkko.sakkinen@linux.intel.com, oshrialkoby85@gmail.com, alexander.steffen@infineon.com, robh+dt@kernel.org, "benoit.houyere@st.com--to=mark.rutland"@arm.com, peterhuewe@gmx.de, christophe-h.richard@st.com, jgg@ziepe.ca, arnd@arndb.de, gregkh@linuxfoundation.org Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, oshri.alkoby@nuvoton.com, tmaimon77@gmail.com, gcwilson@us.ibm.com, kgoldman@us.ibm.com, Dan.Morav@nuvoton.com, oren.tanami@nuvoton.com, shmulik.hager@nuvoton.com, amir.mizinski@nuvoton.com, Amir Mizinski , Benoit Houyere Subject: [PATCH v10 2/8] tpm: tpm_tis: Fix expected bit handling and send all bytes in one shot without last byte in exception Date: Thu, 4 Jun 2020 16:47:07 +0300 Message-Id: <20200604134713.157951-3-amirmizi6@gmail.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20200604134713.157951-1-amirmizi6@gmail.com> References: <20200604134713.157951-1-amirmizi6@gmail.com> MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org From: Amir Mizinski Detected the following incorrect implementation of the send command: polling on the TPM_STS.stsValid field followed by checking the TPM_STS.expect field only once. Since TPM_STS.stsValid represents the TPM_STS.expect validity, both fields should be polled at the same time. This fix modifies the signature of wait_for_tpm_stat(), adding an additional "mask_result" parameter to its call. wait_for_tpm_stat() is now polling the TPM_STS with a mask and waits for the value in mask_result. The fix adds the ability to check if certain TPM_STS bits have been cleared. This change is also aligned to verifying the CRC on I2C TPM. The CRC verification should be done after the TPM_STS.expect field is cleared (TPM received all expected command bytes and set the calculated CRC value in the register). In addition, the send command was changed to comply with TCG_DesignPrinciples_TPM2p0Driver_vp24_pubrev.pdf as follows: - send all command bytes in one loop - remove special handling of the last byte Suggested-by: Benoit Houyere Signed-off-by: Amir Mizinski --- drivers/char/tpm/tpm_tis_core.c | 66 ++++++++++++++--------------------------- 1 file changed, 22 insertions(+), 44 deletions(-) diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index 27c6ca0..6ea70ea 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 wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, u8 mask_result, + unsigned long timeout, wait_queue_head_t *queue, + bool check_cancel) { unsigned long stop; long rc; @@ -55,7 +55,7 @@ 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) == mask_result) return 0; stop = jiffies + timeout; @@ -83,7 +83,7 @@ static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, usleep_range(TPM_TIMEOUT_USECS_MIN, TPM_TIMEOUT_USECS_MAX); status = chip->ops->status(chip); - if ((status & mask) == mask) + if ((status & mask) == mask_result) return 0; } while (time_before(jiffies, stop)); } @@ -281,10 +281,10 @@ 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 = wait_for_tpm_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); @@ -337,8 +337,8 @@ 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 (wait_for_tpm_stat(chip, TPM_STS_VALID, TPM_STS_VALID, + chip->timeout_c, &priv->int_queue, false) < 0) { size = -ETIME; goto out; } @@ -364,61 +364,39 @@ 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 (wait_for_tpm_stat(chip, TPM_STS_COMMAND_READY, + TPM_STS_COMMAND_READY, chip->timeout_b, + &priv->int_queue, false) < 0) { rc = -ETIME; goto out_err; } } - while (count < len - 1) { + while (count < len) { 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); + burstcnt = min_t(int, burstcnt, len - count); rc = tpm_tis_write_bytes(priv, TPM_DATA_FIFO(priv->locality), burstcnt, buf + count); if (rc < 0) goto out_err; count += burstcnt; - - if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, - &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 (wait_for_tpm_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; @@ -470,9 +448,9 @@ 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 (wait_for_tpm_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; } From patchwork Thu Jun 4 13:47:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: amirmizi6@gmail.com X-Patchwork-Id: 199534 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.5 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4D6D9C433E0 for ; Thu, 4 Jun 2020 13:48:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 18CE5206E6 for ; Thu, 4 Jun 2020 13:48:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728718AbgFDNsZ (ORCPT ); Thu, 4 Jun 2020 09:48:25 -0400 Received: from 212.199.177.27.static.012.net.il ([212.199.177.27]:50227 "EHLO herzl.nuvoton.co.il" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728692AbgFDNsX (ORCPT ); Thu, 4 Jun 2020 09:48:23 -0400 Received: from taln60.nuvoton.co.il (ntil-fw [212.199.177.25]) by herzl.nuvoton.co.il (8.13.8/8.13.8) with ESMTP id 054Dlw3g011535; Thu, 4 Jun 2020 16:47:58 +0300 Received: by taln60.nuvoton.co.il (Postfix, from userid 10140) id 3C6D4639BF; Thu, 4 Jun 2020 16:47:58 +0300 (IDT) From: amirmizi6@gmail.com To: Eyal.Cohen@nuvoton.com, jarkko.sakkinen@linux.intel.com, oshrialkoby85@gmail.com, alexander.steffen@infineon.com, robh+dt@kernel.org, "benoit.houyere@st.com--to=mark.rutland"@arm.com, peterhuewe@gmx.de, christophe-h.richard@st.com, jgg@ziepe.ca, arnd@arndb.de, gregkh@linuxfoundation.org Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, oshri.alkoby@nuvoton.com, tmaimon77@gmail.com, gcwilson@us.ibm.com, kgoldman@us.ibm.com, Dan.Morav@nuvoton.com, oren.tanami@nuvoton.com, shmulik.hager@nuvoton.com, amir.mizinski@nuvoton.com, Amir Mizinski , Benoit Houyere Subject: [PATCH v10 6/8] tpm: tpm_tis: verify TPM_STS register is valid after locality request Date: Thu, 4 Jun 2020 16:47:11 +0300 Message-Id: <20200604134713.157951-7-amirmizi6@gmail.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20200604134713.157951-1-amirmizi6@gmail.com> References: <20200604134713.157951-1-amirmizi6@gmail.com> MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org From: Amir Mizinski Issue could result when the TPM does not update TPM_STS register after a locality request (TPM_STS Initial value = 0xFF) and a TPM_STS register read occurs (tpm_tis_status(chip)). Checking the next condition("if ((status & TPM_STS_COMMAND_READY) == 0)"), the status will be at 0xFF and will be 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. Suggested-by: Benoit Houyere Signed-off-by: Amir Mizinski --- drivers/char/tpm/tpm_tis_core.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index 9d90b9a..8868fe0 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -221,8 +221,14 @@ 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 (wait_for_tpm_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)); } From patchwork Thu Jun 4 13:47:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: amirmizi6@gmail.com X-Patchwork-Id: 199531 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.5 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4411BC433E2 for ; Thu, 4 Jun 2020 13:49:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E91920899 for ; Thu, 4 Jun 2020 13:49:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728688AbgFDNs7 (ORCPT ); Thu, 4 Jun 2020 09:48:59 -0400 Received: from 212.199.177.27.static.012.net.il ([212.199.177.27]:50225 "EHLO herzl.nuvoton.co.il" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728685AbgFDNsY (ORCPT ); Thu, 4 Jun 2020 09:48:24 -0400 Received: from taln60.nuvoton.co.il (ntil-fw [212.199.177.25]) by herzl.nuvoton.co.il (8.13.8/8.13.8) with ESMTP id 054DlxF1011541; Thu, 4 Jun 2020 16:47:59 +0300 Received: by taln60.nuvoton.co.il (Postfix, from userid 10140) id 43B36639BF; Thu, 4 Jun 2020 16:47:59 +0300 (IDT) From: amirmizi6@gmail.com To: Eyal.Cohen@nuvoton.com, jarkko.sakkinen@linux.intel.com, oshrialkoby85@gmail.com, alexander.steffen@infineon.com, robh+dt@kernel.org, "benoit.houyere@st.com--to=mark.rutland"@arm.com, peterhuewe@gmx.de, christophe-h.richard@st.com, jgg@ziepe.ca, arnd@arndb.de, gregkh@linuxfoundation.org Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, oshri.alkoby@nuvoton.com, tmaimon77@gmail.com, gcwilson@us.ibm.com, kgoldman@us.ibm.com, Dan.Morav@nuvoton.com, oren.tanami@nuvoton.com, shmulik.hager@nuvoton.com, amir.mizinski@nuvoton.com, Amir Mizinski , Eddie James , Joel Stanley Subject: [PATCH v10 8/8] tpm: tpm_tis: add tpm_tis_i2c driver Date: Thu, 4 Jun 2020 16:47:13 +0300 Message-Id: <20200604134713.157951-9-amirmizi6@gmail.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20200604134713.157951-1-amirmizi6@gmail.com> References: <20200604134713.157951-1-amirmizi6@gmail.com> MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org From: Amir Mizinski Implements the functionality needed to communicate with an I2C TPM according to the TCG TPM I2C Interface Specification. Signed-off-by: Amir Mizinski Tested-by: Eddie James Tested-by: Joel Stanley --- drivers/char/tpm/Kconfig | 12 ++ drivers/char/tpm/Makefile | 1 + drivers/char/tpm/tpm_tis_i2c.c | 292 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 305 insertions(+) create mode 100644 drivers/char/tpm/tpm_tis_i2c.c diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig index aacdeed..2116d94 100644 --- a/drivers/char/tpm/Kconfig +++ b/drivers/char/tpm/Kconfig @@ -74,6 +74,18 @@ config TCG_TIS_SPI_CR50 If you have a H1 secure module running Cr50 firmware on SPI bus, say Yes and it will be accessible from within Linux. +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 which is connected to a regular + I2C master (i.e. most embedded platforms) that is compliant with the + TCG TPM I2C Interface Specification 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_ATMEL tristate "TPM Interface Specification 1.2 Interface (I2C - Atmel)" depends on I2C diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile index 9567e51..97999cf 100644 --- a/drivers/char/tpm/Makefile +++ b/drivers/char/tpm/Makefile @@ -26,6 +26,7 @@ obj-$(CONFIG_TCG_TIS_SPI) += tpm_tis_spi.o tpm_tis_spi-y := tpm_tis_spi_main.o tpm_tis_spi-$(CONFIG_TCG_TIS_SPI_CR50) += tpm_tis_spi_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 0000000..4c9bad0 --- /dev/null +++ b/drivers/char/tpm/tpm_tis_i2c.c @@ -0,0 +1,292 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2014-2019 Nuvoton Technology corporation + * + * TPM TIS I2C + * + * TPM TIS I2C Device Driver Interface for devices that implement the TPM I2C + * Interface defined by TCG PC Client Platform TPM Profile (PTP) Specification + * Revision 01.03 v22 at www.trustedcomputinggroup.org + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include "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_DATA_CSUM 0x44 +#define TPM_I2C_DID_VID 0x48 +#define TPM_I2C_RID 0x4C + +//#define I2C_IS_TPM2 1 + +struct tpm_tis_i2c_phy { + struct tpm_tis_data priv; + struct i2c_client *i2c_client; + bool data_csum; + 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); + int ret = 0; + int i = 0; + u8 reg = address_to_register(addr); + struct i2c_msg msgs[] = { + { + .addr = phy->i2c_client->addr, + .len = sizeof(reg), + .buf = ®, + }, + { + .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 = ®, + }, + { + .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; +} + +static bool tpm_tis_i2c_verify_data_integrity(struct tpm_tis_data *data, + const u8 *buf, size_t len) +{ + struct tpm_tis_i2c_phy *phy = to_tpm_tis_i2c_phy(data); + u16 crc, crc_tpm; + int rc; + + if (phy->data_csum) { + crc = crc_ccitt(0x0000, buf, len); + rc = tpm_tis_read16(data, TPM_DATA_CSUM, &crc_tpm); + if (rc < 0) + return false; + + crc_tpm = be16_to_cpu(crc_tpm); + return crc == crc_tpm; + } + + return true; +} + +static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume); + +static int csum_state_store(struct tpm_tis_data *data, u8 new_state) +{ + struct tpm_tis_i2c_phy *phy = to_tpm_tis_i2c_phy(data); + u8 cur_state; + int rc; + + rc = tpm_tis_i2c_write_bytes(&phy->priv, TPM_DATA_CSUM_ENABLE, + 1, &new_state); + if (rc < 0) + return rc; + + rc = tpm_tis_i2c_read_bytes(&phy->priv, TPM_DATA_CSUM_ENABLE, + 1, &cur_state); + if (rc < 0) + return rc; + + if (new_state == cur_state) + phy->data_csum = (bool)new_state; + + return rc; +} + +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, + .verify_data_integrity = tpm_tis_i2c_verify_data_integrity, +}; + +static int tpm_tis_i2c_probe(struct i2c_client *dev, + const struct i2c_device_id *id) +{ + struct tpm_tis_i2c_phy *phy; + int rc; + int crc_checksum = 0; + const u8 loc_init = 0; + struct device_node *np; + + 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; + + // set CRC checksum calculation enable + np = dev->dev.of_node; + if (of_property_read_bool(np, "crc-checksum")) + crc_checksum = 1; + + rc = csum_state_store(&phy->priv, crc_checksum); + 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 const struct acpi_device_id acpi_tis_i2c_match[] = { + {"SMO0768", 0}, + {} +}; +MODULE_DEVICE_TABLE(acpi, acpi_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), + .acpi_match_table = ACPI_PTR(acpi_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");