Signed-off-by: Oshri Alkoby <oshrialkoby85@xxxxxxxxx> --- drivers/char/tpm/Kconfig | 22 + drivers/char/tpm/Makefile | 1 + drivers/char/tpm/tpm_i2c_ptp.c | 1099 ++++++++++++++++++++++++++++++++ 3 files changed, 1122 insertions(+) create mode 100644 drivers/char/tpm/tpm_i2c_ptp.c diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig index 88a3c06fc153..ea4138145191 100644 --- a/drivers/char/tpm/Kconfig +++ b/drivers/char/tpm/Kconfig @@ -97,6 +97,28 @@ config TCG_TIS_I2C_NUVOTON To compile this driver as a module, choose M here; the module will be called tpm_i2c_nuvoton. +config TCG_TIS_I2C_PTP + tristate "TPM Interface Specification 1.2/2.0 Interface (I2C - PTP)" + depends on I2C + select CRC_CCITT + ---help--- + If you have a TPM security chip with an I2C interface that impelements + the TPM I2C interface protocol defined by the PTP 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_i2c_ptp. + +config TCG_TIS_I2C_PTP_MAX_SIZE + prompt "Max I2C Buffer Size" + depends on TCG_TIS_I2C_PTP + int + default 32 + help + Set the maximal I2C buffer size. This will alter the default value. A + different size can be set by using a module parameter (i2c_max_size) + as well. If no parameter is provided when loading, this is the value + that will be used. + config TCG_NSC tristate "National Semiconductor TPM Interface" depends on X86 diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile index a01c4cab902a..d736f22205cb 100644 --- a/drivers/char/tpm/Makefile +++ b/drivers/char/tpm/Makefile @@ -25,6 +25,7 @@ obj-$(CONFIG_TCG_TIS_SPI) += tpm_tis_spi.o obj-$(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 +obj-$(CONFIG_TCG_TIS_I2C_PTP) += tpm_i2c_ptp.o obj-$(CONFIG_TCG_NSC) += tpm_nsc.o obj-$(CONFIG_TCG_ATMEL) += tpm_atmel.o obj-$(CONFIG_TCG_INFINEON) += tpm_infineon.o diff --git a/drivers/char/tpm/tpm_i2c_ptp.c b/drivers/char/tpm/tpm_i2c_ptp.c new file mode 100644 index 000000000000..cc1065b79c2d --- /dev/null +++ b/drivers/char/tpm/tpm_i2c_ptp.c @@ -0,0 +1,1099 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2014-2019 Nuvoton Technology corporation + * + * TPM I2C PTP + * + * TPM 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 <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/i2c.h> +#include <linux/freezer.h> +#include <linux/of_device.h> +#include <linux/gpio.h> +#include <linux/of_gpio.h> +#include <linux/crc-ccitt.h> +#include "tpm.h" + +/* I2C interface offsets */ +#define TPM_LOC_SEL 0x00 +#define TPM_ACCESS 0x04 +#define TPM_INT_ENABLE 0x08 +#define TPM_INT_STATUS 0x10 +#define TPM_INT_CAPABILITY 0x14 +#define TPM_STS 0x18 +#define TPM_STS_BURST_COUNT 0x19 +#define TPM_DATA_FIFO 0x24 +#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_VID_DID 0x48 +#define TPM_RID 0x4C + + /* max. command/response length */ +#define TPM_I2C_BUFSIZE 2048 + +/* I2C bus device maximum buffer size w/o counting I2C address or command */ +#define TPM_I2C_MAX_BUF_SIZE 32 + +#define TPM_I2C_MAX_RETRY_CNT 5 +#define TPM_I2C_RETRY_DELAY_SHORT_US (2 * 1000) +#define TPM_I2C_RETRY_DELAY_LONG_US (10 * 1000) +#define TPM_I2C_DELAY_RANGE_US 300 + +#define OF_IS_TPM2 ((void *)1) +#define I2C_IS_TPM2 1 + +struct tpm_tis_data { + u16 manufacturer_id; + int locality; + int irq; + bool irq_tested; + unsigned int flags; + wait_queue_head_t int_queue; + wait_queue_head_t read_queue; + const struct tpm_tis_phy_ops *phy_ops; + unsigned int intrs; + unsigned short rng_quality; +}; + +#define MAX_COUNT 3 +#define SLEEP_DURATION_LOW 55 +#define SLEEP_DURATION_HI 65 + +static int iic_tpm_read(struct i2c_client *client, u8 addr, u8 *buffer, + size_t len) +{ + struct i2c_msg msg1 = { + .addr = client->addr, + .len = 1, + .buf = &addr + }; + struct i2c_msg msg2 = { + .addr = client->addr, + .flags = I2C_M_RD, + .len = len, + .buf = buffer + }; + int rc = 0; + int count; + + if (!client->adapter->algo->master_xfer) + return -EOPNOTSUPP; + i2c_lock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER); + for (count = 0; count < MAX_COUNT; count++) { + rc = __i2c_transfer(client->adapter, &msg1, 1); + if (rc > 0) + break; /* break here to skip sleep */ + usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI); + } + if (rc <= 0) + goto out; + for (count = 0; count < MAX_COUNT; count++) { + rc = __i2c_transfer(client->adapter, &msg2, 1); + if (rc > 0) + break; + usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI); + } +out: + i2c_unlock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER); + usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI); + if (rc <= 0) + return -EIO; + return len; +} + +static u8 tpm_dev_buf[TPM_I2C_BUFSIZE + sizeof(u8)]; /* max buff size + addr */ + +#ifdef CONFIG_TCG_TIS_I2C_PTP_MAX_SIZE + static int i2c_max_size = CONFIG_TCG_TIS_I2C_PTP_MAX_SIZE; +#else + static int i2c_max_size = TPM_I2C_MAX_BUF_SIZE; +#endif +module_param(i2c_max_size, int, 0660); + +static int iic_tpm_write_generic(struct i2c_client *client, + u8 addr, u8 *buffer, size_t len, + unsigned int sleep_low, + unsigned int sleep_hi, u8 max_count) +{ + int rc = -EIO; + int count; + struct i2c_msg msg1 = { + .addr = client->addr, + .len = len + 1, + .buf = tpm_dev_buf + }; + + if (len > TPM_BUFSIZE) + return -EINVAL; + if (!client->adapter->algo->master_xfer) + return -EOPNOTSUPP; + i2c_lock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER); + tpm_dev_buf[0] = addr; + memcpy(&tpm_dev_buf[1], buffer, len); + for (count = 0; count < max_count; count++) { + rc = __i2c_transfer(client->adapter, &msg1, 1); + if (rc > 0) + break; + usleep_range(sleep_low, sleep_hi); + } + i2c_unlock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER); + usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI); + if (rc <= 0) + return -EIO; + return 0; +} + +static s32 i2c_ptp_read_buf(struct i2c_client *client, u8 offset, size_t size, + u8 *data) +{ + s32 status; + + status = iic_tpm_read(client, offset, data, size); + dev_dbg(&client->dev, + "%s(offset=%u size=%zu data=%*ph) -> sts=%d\n", __func__, + offset, size, (int)size, data, status); + return status; +} + +static s32 i2c_ptp_write_buf(struct i2c_client *client, u8 offset, size_t size, + u8 *data) +{ + s32 status; + + status = iic_tpm_write_generic(client, offset, data, size, + SLEEP_DURATION_LOW, SLEEP_DURATION_HI, + MAX_COUNT); + dev_dbg(&client->dev, + "%s(offset=%u size=%zu data=%*ph) -> sts=%d\n", __func__, + offset, size, (int)size, data, status); + + return status; +} + +#define TPM_INT_DATA_AVAIL (BIT(0)) +#define TPM_INT_STS_VALID (BIT(1)) +#define TPM_INT_LOC_CHANGED (BIT(2)) +#define TPM_INT_CMD_READY (BIT(7)) +#define TPM_INT_GLOBAL (BIT(31)) + +#define TPM_INT_TO_ACTIVATE (TPM_INT_DATA_AVAIL) + +static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, + bool check_cancel, bool *canceled) +{ + u8 status = chip->ops->status(chip); + + *canceled = false; + if (status != 0xff && (status & mask) == mask) + return true; + if (check_cancel && chip->ops->req_canceled(chip, status)) { + *canceled = true; + return true; + } + return false; +} + +int i2c_ptp_wait_for_tpm_stat_l(struct tpm_chip *chip, u8 mask, + unsigned long timeout, wait_queue_head_t *queue, + bool check_cancel) +{ + struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); + unsigned long stop, start, long_delay; + long rc; + u8 status; + bool canceled = false; + unsigned int cur_intrs; + + start = jiffies; + stop = start + timeout; + long_delay = start + usecs_to_jiffies(TPM_I2C_RETRY_DELAY_LONG_US); + + if (queue && chip->flags & TPM_CHIP_FLAG_IRQ) { +again: + cur_intrs = priv->intrs; + timeout = stop - jiffies; + if ((long)timeout <= 0) + return -ETIME; + + enable_irq(priv->irq); + rc = wait_event_interruptible_timeout(*queue, + ((cur_intrs != priv->intrs) && + wait_for_tpm_stat_cond(chip, mask, check_cancel, &canceled)), + timeout); + if (rc > 0) { + if (canceled) + return -ECANCELED; + return 0; + } + if (rc == -ERESTARTSYS && freezing(current)) { + clear_thread_flag(TIF_SIGPENDING); + goto again; + } + } else { + do { + status = chip->ops->status(chip); + if (status != 0xff && (status & mask) == mask) + return 0; + + if (time_before(jiffies, long_delay)) + usleep_range(TPM_I2C_RETRY_DELAY_SHORT_US, + TPM_I2C_RETRY_DELAY_SHORT_US + + TPM_I2C_DELAY_RANGE_US); + else + usleep_range(TPM_I2C_RETRY_DELAY_LONG_US, + TPM_I2C_RETRY_DELAY_LONG_US + + TPM_I2C_DELAY_RANGE_US); + + } while (time_before(jiffies, stop)); + } + return -ETIME; +} + +/* wrapper of wait_for_tpm_stat, since we can't do the int processing during + * the int_handler in I2C, here we do it after the int_handler is done and + * wait_for_tpm_stat retruns + */ +static int i2c_ptp_wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, + unsigned long timeout, + wait_queue_head_t *queue, + bool check_cancel) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + u32 intsts; + int rc; + + rc = i2c_ptp_wait_for_tpm_stat_l(chip, mask, timeout, queue, + check_cancel); + if (rc < 0) + return rc; + + if (chip->flags & TPM_CHIP_FLAG_IRQ) { + rc = i2c_ptp_read_buf(client, TPM_INT_STATUS, 4, (u8 *)&intsts); + if (rc < 0) { + dev_err(&chip->dev, + "%s() fail to read TPM_INT_STATUS\n", __func__); + return -EIO; + } + + /* Clear interrupts handled */ + rc = i2c_ptp_write_buf(client, TPM_INT_STATUS, 4, + (u8 *)&intsts); + if (rc < 0) { + dev_err(&chip->dev, + "%s() fail to clear int status\n", __func__); + return -EIO; + } + } + + return 0; +} + +#define TPM_ACCESS_REQUEST_USE (BIT(1)) +#define TPM_ACCESS_REQUEST_PENDING (BIT(2)) +#define TPM_ACCESS_ACTIVE_LOCALITY (BIT(5)) +#define TPM_ACCESS_VALID_STS (BIT(7)) + +/* 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 i2c_client *client = to_i2c_client(chip->dev.parent); + unsigned long stop = jiffies + chip->timeout_a; + + do { + int rc; + u8 access; + + rc = i2c_ptp_read_buf(client, TPM_ACCESS, 1, &access); + if (rc < 0) + return rc; + + if (access != 0xff && (access & TPM_ACCESS_VALID_STS) != 0) + return 0; + tpm_msleep(TPM_TIMEOUT); + } while (time_before(jiffies, stop)); + return -1; +} + +static bool i2c_ptp_check_locality(struct tpm_chip *chip, int l) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); + int rc; + u8 access; + u8 data; + + data = (u8)l; + rc = i2c_ptp_write_buf(client, TPM_LOC_SEL, 1, &data); + if (rc < 0) + return false; + + rc = i2c_ptp_read_buf(client, TPM_ACCESS, 1, &access); + if (rc < 0) + return false; + + if ((access & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID_STS)) == + (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID_STS)) { + priv->locality = l; + return true; + } + + return false; +} + +static bool i2c_ptp_locality_inactive(struct tpm_chip *chip, int l) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + int rc; + u8 access; + u8 data; + + data = (u8)l; + rc = i2c_ptp_write_buf(client, TPM_LOC_SEL, 1, &data); + if (rc < 0) + return false; + + rc = i2c_ptp_read_buf(client, TPM_ACCESS, 1, &access); + if (rc < 0) + return false; + + if ((access & (TPM_ACCESS_VALID_STS | TPM_ACCESS_ACTIVE_LOCALITY)) + == TPM_ACCESS_VALID_STS) + return true; + + return false; +} + +static int i2c_ptp_release_locality(struct tpm_chip *chip, int l) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + unsigned long stop; + int rc; + u8 data; + + if (i2c_ptp_locality_inactive(chip, l)) + return 0; + + data = TPM_ACCESS_ACTIVE_LOCALITY; + rc = i2c_ptp_write_buf(client, TPM_ACCESS, 1, &data); + if (rc < 0) + return rc; + + stop = jiffies + chip->timeout_a; + do { + if (i2c_ptp_locality_inactive(chip, l)) + return 0; + + tpm_msleep(TPM_TIMEOUT); + } while (time_before(jiffies, stop)); + + return -1; +} + +static int i2c_ptp_request_locality(struct tpm_chip *chip, int l) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + unsigned long stop; + int rc; + u8 data; + + if (i2c_ptp_check_locality(chip, l)) + return l; + + data = TPM_ACCESS_REQUEST_USE; + rc = i2c_ptp_write_buf(client, TPM_ACCESS, 1, &data); + if (rc < 0) + return rc; + + stop = jiffies + chip->timeout_a; + + do { + if (i2c_ptp_check_locality(chip, l)) + return l; + + rc = i2c_ptp_write_buf(client, TPM_ACCESS, 1, &data); + if (rc < 0) + return rc; + + tpm_msleep(TPM_TIMEOUT); + } while (time_before(jiffies, stop)); + + return -1; +} + +#define TPM_STS_RESPONSE_RETRY (BIT(1)) +#define TPM_STS_SELFTEST_DONE (BIT(2)) +#define TPM_STS_EXPECT (BIT(3)) +#define TPM_STS_DATA_AVAIL (BIT(4)) +#define TPM_STS_GO (BIT(5)) +#define TPM_STS_COMMAND_READY (BIT(6)) +#define TPM_STS_VALID (BIT(7)) +#define TPM_STS_COMMAND_CANCEL (BIT(24)) + +/* bit1...bit0 reads always 0 */ +#define TPM_STS_ERR_VAL (BIT(0) | BIT(1)) + +/* read TPM_STS register */ +static u8 i2c_ptp_status(struct tpm_chip *chip) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + int rc; + u8 status; + + rc = i2c_ptp_read_buf(client, TPM_STS, 1, &status); + if (rc < 0) + return 0; + + return status; +} + +/* write commandReady to TPM_STS register */ +static void i2c_ptp_ready(struct tpm_chip *chip) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + u8 data; + + data = TPM_STS_COMMAND_READY; + i2c_ptp_write_buf(client, TPM_STS, 1, &data); +} + +/* read Burst Count */ +static int i2c_ptp_get_burstcount(struct tpm_chip *chip) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + unsigned long stop; + int burstcnt = 0, rc; + + /* wait for burstcount */ + stop = jiffies + chip->timeout_a; + + do { + rc = i2c_ptp_read_buf(client, TPM_STS_BURST_COUNT, 2, + (u8 *)&burstcnt); + if (rc < 0) + return rc; + + if (burstcnt) + return burstcnt; + + usleep_range(TPM_TIMEOUT_USECS_MIN, TPM_TIMEOUT_USECS_MAX); + } while (time_before(jiffies, stop)); + + return -EBUSY; +} + +/* write commandCancel to TPM_STS register */ +static void i2c_ptp_cancel(struct tpm_chip *chip) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + u32 data; + + data = TPM_STS_COMMAND_CANCEL; + i2c_ptp_write_buf(client, TPM_STS, 4, (u8 *)&data); +} + +/* enable checksum */ +static int i2c_ptp_enable_csum(struct tpm_chip *chip) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + s32 rc; + u8 data = 1; + + /* Enable CSUM */ + rc = i2c_ptp_write_buf(client, TPM_DATA_CSUM_ENABLE, 1, &data); + if (rc < 0) { + dev_err(&chip->dev, + "%s() fail to read to TPM_DATA_CSUM_ENABLE: %d\n", + __func__, rc); + return rc; + } + return 0; +} + +/* Caclculate crc16 of the buffer and compares it to TPM_DATA_CSUM */ +static int i2c_ptp_check_crc(struct tpm_chip *chip, u8 *buf, size_t len) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + s32 status; + u16 tpm_csum = 0; + u16 crc = 0; + + crc = crc_ccitt(crc, buf, len); + crc = be16_to_cpu(crc); + status = i2c_ptp_read_buf(client, TPM_DATA_CSUM, 2, (u8 *)&tpm_csum); + if (status <= 0) { + dev_err(&chip->dev, "%s() fail to read to TPM_DATA_CSUM: %d\n", + __func__, status); + return -EIO; + } + + if (tpm_csum != crc) { + dev_err(&chip->dev, "%s() bad data csum\n", __func__); + return -EIO; + } + + return 0; +} + +static int i2c_ptp_recv_data(struct tpm_chip *chip, u8 *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + int size = 0, burstcnt, rc, bytes2read = count; + bool paramsize_flag = false; + + while (size < bytes2read) { + burstcnt = i2c_ptp_get_burstcount(chip); + if (burstcnt <= 0) + return burstcnt; + + burstcnt = min_t(int, (bytes2read - size), burstcnt); + rc = i2c_ptp_read_buf(client, TPM_DATA_FIFO, burstcnt, + buf + size); + if (rc < 0) + return rc; + + size += burstcnt; + + if (size >= 6 && !paramsize_flag) { + bytes2read = be32_to_cpu(*(__be32 *)(buf + 2)); + paramsize_flag = true; + } + } + + return size; +} + +static int i2c_ptp_recv(struct tpm_chip *chip, u8 *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + int size = 0; + int status, retries; + + if (count < TPM_HEADER_SIZE) { + status = -EIO; + goto out; + } + + for (retries = 0; retries < TPM_I2C_MAX_RETRY_CNT; retries++) { + size = 0; + + if (retries > 0) { + /* if this is not the first trial, set responseRetry */ + u8 data = TPM_STS_RESPONSE_RETRY; + + i2c_ptp_write_buf(client, TPM_STS, 1, &data); + } + + status = i2c_ptp_wait_for_tpm_stat(chip, + (TPM_STS_DATA_AVAIL | TPM_STS_VALID), + chip->timeout_b, NULL, + false); + if (status < 0) + return status; + + size = i2c_ptp_recv_data(chip, buf, TPM_HEADER_SIZE); + if (size < TPM_HEADER_SIZE) + continue; + + status = i2c_ptp_wait_for_tpm_stat(chip, TPM_STS_VALID, + chip->timeout_a, NULL, + false); + if (status < 0) + continue; + + /* check CRC */ + status = i2c_ptp_check_crc(chip, buf, size); + if (status < 0) + continue; + + status = size; + break; + } + +out: + i2c_ptp_ready(chip); + return status; +} + +/* + * 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 i2c_ptp_send_data(struct tpm_chip *chip, u8 *buf, size_t len) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + int rc, status, burstcnt, retries; + size_t count = 0, bytes2send; + u32 ordinal = be32_to_cpu(*((__be32 *)(buf + 6))); + u32 intmask; + + /* When NPCT7XX FU Mode command or startup (when TPM I2C may be has + * been reset), wait for STS_VALID and re-initialize I2C regs + */ + if (ordinal == 0x20000201 || ordinal == 0x144) { + // wait for I2C to be ready + if (wait_startup(chip, 0) != 0) + return -ENODEV; + + rc = i2c_ptp_enable_csum(chip); + if (rc < 0) { + dev_err(&chip->dev, "%s() fail to enable checksum\n", + __func__); + return rc; + } + + // in interrupt mode re-eanble and clear the interrupts + if (chip->flags & TPM_CHIP_FLAG_IRQ) { + intmask = (TPM_INT_TO_ACTIVATE | TPM_INT_GLOBAL); + i2c_ptp_write_buf(client, TPM_INT_ENABLE, 4, + (u8 *)&intmask); + i2c_ptp_write_buf(client, TPM_INT_STATUS, 4, + (u8 *)&intmask); + } + } + + for (retries = 0; retries < TPM_I2C_MAX_RETRY_CNT; retries++) { + count = 0; + rc = -1; + + if (retries > 0) { + /* if this is not the first trial, abort the command */ + i2c_ptp_ready(chip); + } + + status = i2c_ptp_status(chip); + if ((status & TPM_STS_COMMAND_READY) == 0) { + i2c_ptp_ready(chip); + if (i2c_ptp_wait_for_tpm_stat + (chip, TPM_STS_COMMAND_READY, chip->timeout_b, + NULL, false) < 0) { + rc = -ETIME; + continue; + } + } + + while (count < len) { + burstcnt = i2c_ptp_get_burstcount(chip); + if (burstcnt < 0) { + dev_err(&chip->dev, "Unable to read burstcount\n"); + rc = burstcnt; + break; + } + + bytes2send = min_t(int, i2c_max_size, burstcnt); + bytes2send = min_t(int, bytes2send, (len - count)); + rc = i2c_ptp_write_buf(client, TPM_DATA_FIFO, + bytes2send, buf + count); + if (rc < 0) + break; + + count += bytes2send; + } + + if (rc < 0) + continue; + + if (i2c_ptp_wait_for_tpm_stat(chip, TPM_STS_VALID, + chip->timeout_a, NULL, + false) < 0) { + rc = -ETIME; + continue; + } + + /* check CRC */ + rc = i2c_ptp_check_crc(chip, buf, len); + if (rc < 0) + continue; + + return 0; + } + + i2c_ptp_ready(chip); + return rc; +} + +static void disable_interrupts(struct tpm_chip *chip) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); + u32 intmask; + int rc; + + rc = i2c_ptp_read_buf(client, TPM_INT_ENABLE, 4, (u8 *)&intmask); + if (rc < 0) + intmask = 0; + + intmask &= ~TPM_INT_GLOBAL; + rc = i2c_ptp_write_buf(client, TPM_INT_ENABLE, 4, (u8 *)&intmask); + if (rc < 0) + dev_err(&chip->dev, "%s() fail to write TPM_INT_ENABLE\n", + __func__); + + 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 i2c_ptp_send_main(struct tpm_chip *chip, u8 *buf, size_t len) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); + int rc; + u32 ordinal; + unsigned long dur; + u8 data; + + rc = i2c_ptp_send_data(chip, buf, len); + if (rc < 0) + return rc; + + /* go and do it */ + data = TPM_STS_GO; + rc = i2c_ptp_write_buf(client, TPM_STS, 1, &data); + if (rc < 0) + goto out_err; + + ordinal = be32_to_cpu(*((__be32 *)(buf + 6))); + + dur = tpm_calc_ordinal_duration(chip, ordinal); + if (i2c_ptp_wait_for_tpm_stat + (chip, TPM_STS_DATA_AVAIL | TPM_STS_VALID, dur, + &priv->int_queue, false) < 0) { + rc = -ETIME; + goto out_err; + } + + return 0; +out_err: + i2c_ptp_ready(chip); + return rc; +} + +static int i2c_ptp_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 i2c_ptp_send_main(chip, buf, len); + + /* Verify receipt of the expected IRQ */ + irq = priv->irq; + chip->flags &= ~TPM_CHIP_FLAG_IRQ; + rc = i2c_ptp_send_main(chip, buf, len); + priv->irq = irq; + chip->flags |= TPM_CHIP_FLAG_IRQ; + if (!priv->irq_tested) + tpm_msleep(1); + if (!priv->irq_tested) + disable_interrupts(chip); + priv->irq_tested = true; + return rc; +} + +static bool i2c_ptp_req_canceled(struct tpm_chip *chip, u8 status) +{ + return (status == TPM_STS_COMMAND_READY); +} + +/* The only purpose for the handler is to signal to any waiting threads that + * the interrupt is currently being asserted. The driver does not do any + * processing triggered by interrupts, and the chip provides no way to mask at + * the source (plus that would be slow over I2C). Run the IRQ as a one-shot, + * this means it cannot be shared. The processing of the interrupt status + * is done in i2c_ptp_wait_for_tpm_stat + */ +static irqreturn_t i2c_ptp_int_handler(int dummy, void *dev_id) +{ + struct tpm_chip *chip = dev_id; + struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); + + priv->irq_tested = true; + priv->intrs++; + wake_up_interruptible(&priv->int_queue); + disable_irq_nosync(priv->irq); + return IRQ_HANDLED; +} + +static int i2c_ptp_gen_interrupt(struct tpm_chip *chip) +{ + const char *desc = "attempting to generate an interrupt"; + u32 cap2; + + return tpm2_get_tpm_pt(chip, 0x100, &cap2, 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 i2c_ptp_probe_irq_single(struct tpm_chip *chip, u32 intmask, + int flags, int irq) +{ + struct i2c_client *client = to_i2c_client(chip->dev.parent); + struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); + int rc; + u32 int_support; + + if (devm_request_irq(chip->dev.parent, irq, i2c_ptp_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; + + chip->flags |= TPM_CHIP_FLAG_IRQ; + + /* check what are the interrupts that the TPM supports */ + rc = i2c_ptp_read_buf(client, TPM_INT_CAPABILITY, 4, (u8 *) + &int_support); + if (rc < 0) + return rc; + + /* Clear all existing */ + rc = i2c_ptp_write_buf(client, TPM_INT_STATUS, 4, (u8 *)&int_support); + if (rc < 0) + return rc; + + /* Turn on */ + int_support &= TPM_INT_TO_ACTIVATE; + int_support |= TPM_INT_GLOBAL; + rc = i2c_ptp_write_buf(client, TPM_INT_ENABLE, 4, (u8 *)&int_support); + if (rc < 0) + return rc; + + priv->irq_tested = false; + + /* Generate an interrupt by having the core call through to + * i2c_ptp_send + */ + rc = i2c_ptp_gen_interrupt(chip); + if (rc < 0) + return rc; + + return 0; +} + +static int i2c_ptp_remove(struct i2c_client *client) +{ + u32 interrupt; + int rc; + + rc = i2c_ptp_read_buf(client, TPM_INT_ENABLE, 4, (u8 *)&interrupt); + if (rc < 0) + interrupt = 0; + + // Clear and disable interrupts + interrupt &= ~TPM_INT_GLOBAL; + rc = i2c_ptp_write_buf(client, TPM_INT_STATUS, 4, (u8 *)&interrupt); + rc = i2c_ptp_write_buf(client, TPM_INT_ENABLE, 4, (u8 *)&interrupt); + + return rc; +} +EXPORT_SYMBOL_GPL(i2c_ptp_remove); + +static const struct tpm_class_ops tpm_i2c = { + .flags = TPM_OPS_AUTO_STARTUP, + .status = i2c_ptp_status, + .recv = i2c_ptp_recv, + .send = i2c_ptp_send, + .cancel = i2c_ptp_cancel, + .req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID, + .req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID, + .req_canceled = i2c_ptp_req_canceled, + .request_locality = i2c_ptp_request_locality, + .relinquish_locality = i2c_ptp_release_locality, +}; + +int i2c_ptp_core_init(struct i2c_client *client, struct tpm_tis_data *priv, + int irq, const struct tpm_tis_phy_ops *phy_ops, + acpi_handle acpi_dev_handle) +{ + u32 vendor; + u32 intmask; + u8 rid; + int rc; + struct tpm_chip *chip; + struct device *dev = &client->dev; + + chip = tpmm_chip_alloc(dev, &tpm_i2c); + if (IS_ERR(chip)) + return PTR_ERR(chip); + + chip->hwrng.quality = priv->rng_quality; + + /* Maximum timeouts */ + chip->timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A); + chip->timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B); + chip->timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C); + chip->timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D); + priv->phy_ops = phy_ops; + priv->intrs = 0; + 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 = i2c_ptp_read_buf(client, TPM_INT_ENABLE, 4, (u8 *)&intmask); + if (rc < 0) + goto out_err; + + intmask = TPM_INT_TO_ACTIVATE; // global should be off now + i2c_ptp_write_buf(client, TPM_INT_ENABLE, 4, (u8 *)&intmask); + + rc = i2c_ptp_enable_csum(chip); + if (rc < 0) { + dev_err(&chip->dev, "%s() fail to enable checksum\n", __func__); + rc = -ENODEV; + goto out_err; + } + + rc = tpm_chip_start(chip); + if (rc) + goto out_err; + + rc = tpm2_probe(chip); + if (rc) + goto out_err; + + rc = i2c_ptp_read_buf(client, TPM_VID_DID, 4, (u8 *)&vendor); + if (rc < 0) + goto out_err; + + priv->manufacturer_id = vendor; + + rc = i2c_ptp_read_buf(client, TPM_RID, 1, &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); + + /* INTERRUPT Setup */ + init_waitqueue_head(&priv->int_queue); + if (irq != -1) { + /* Before doing irq testing 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; + } + + i2c_ptp_probe_irq_single(chip, intmask, IRQF_TRIGGER_LOW, irq); + if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) + dev_err(&chip->dev, FW_BUG + "TPM interrupt not working, polling instead\n"); + } + + rc = tpm_chip_register(chip); + if (rc) + goto out_err; + + return 0; + +out_err: + i2c_ptp_remove(client); + + return rc; +} + +static int i2c_ptp_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int irq = -1, gpio; + struct tpm_tis_data *priv; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA)) + return -ENODEV; + + priv = devm_kzalloc(&client->dev, sizeof(struct tpm_tis_data), + GFP_KERNEL); + if (!priv) + return -ENOMEM; + + if (i2c_max_size < 1) + i2c_max_size = CONFIG_TCG_TIS_I2C_PTP_MAX_SIZE; + + // Get interrupt from board device + if (client->irq) { + irq = client->irq; + goto out; + } + + // If IRQ doesn't exists, get GPIO from device tree + gpio = of_get_named_gpio(client->dev.of_node, "tpm-pirq", 0); + if (gpio < 0) { + dev_err(&client->dev, "Failed to retrieve tpm-pirq\n"); + goto out; + } + + // GPIO request and configuration + if (devm_gpio_request_one(&client->dev, gpio, GPIOF_IN, "TPM PIRQ")) { + dev_err(&client->dev, "Failed to request tpm-pirq pin\n"); + goto out; + } + + irq = gpio_to_irq(gpio); + +out: + return i2c_ptp_core_init(client, priv, irq, NULL, 0); +} + +static const struct of_device_id of_i2c_ptp_match[] = { + {.compatible = "tcg,tpm_i2c_ptp", .data = OF_IS_TPM2}, + {}, +}; + +static const struct i2c_device_id i2c_ptp_id[] = { + {"tpm_i2c_ptp"}, + {"tpm2_i2c_ptp", .driver_data = I2C_IS_TPM2}, + {} +}; +MODULE_DEVICE_TABLE(i2c, i2c_ptp_id); + +static SIMPLE_DEV_PM_OPS(i2c_ptp_pm_ops, tpm_pm_suspend, tpm_pm_resume); + +static struct i2c_driver i2c_ptp_driver = { + .id_table = i2c_ptp_id, + .probe = i2c_ptp_probe, + .remove = i2c_ptp_remove, + .driver = { + .name = "tpm_i2c_ptp", + .pm = &i2c_ptp_pm_ops, + .of_match_table = of_match_ptr(of_i2c_ptp_match), + }, +}; +module_i2c_driver(i2c_ptp_driver); + +MODULE_AUTHOR("Oshri Alkoby (oshri.alkoby@xxxxxxxxxxx)"); +MODULE_DESCRIPTION("TPM I2C Driver"); +MODULE_VERSION("2.1.3"); +MODULE_LICENSE("GPL"); -- 2.18.0