741 строка
18 KiB
C
741 строка
18 KiB
C
/*
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* Copyright (C) 2012,2013 Infineon Technologies
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*
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* Authors:
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* Peter Huewe <peter.huewe@infineon.com>
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*
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* Device driver for TCG/TCPA TPM (trusted platform module).
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* Specifications at www.trustedcomputinggroup.org
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*
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* This device driver implements the TPM interface as defined in
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* the TCG TPM Interface Spec version 1.2, revision 1.0 and the
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* Infineon I2C Protocol Stack Specification v0.20.
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*
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* It is based on the original tpm_tis device driver from Leendert van
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* Dorn and Kyleen Hall.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation, version 2 of the
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* License.
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*
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*
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*/
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#include <linux/i2c.h>
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#include <linux/module.h>
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#include <linux/wait.h>
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#include "tpm.h"
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/* max. buffer size supported by our TPM */
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#define TPM_BUFSIZE 1260
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/* max. number of iterations after I2C NAK */
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#define MAX_COUNT 3
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#define SLEEP_DURATION_LOW 55
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#define SLEEP_DURATION_HI 65
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/* max. number of iterations after I2C NAK for 'long' commands
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* we need this especially for sending TPM_READY, since the cleanup after the
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* transtion to the ready state may take some time, but it is unpredictable
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* how long it will take.
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*/
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#define MAX_COUNT_LONG 50
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#define SLEEP_DURATION_LONG_LOW 200
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#define SLEEP_DURATION_LONG_HI 220
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/* After sending TPM_READY to 'reset' the TPM we have to sleep even longer */
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#define SLEEP_DURATION_RESET_LOW 2400
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#define SLEEP_DURATION_RESET_HI 2600
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/* we want to use usleep_range instead of msleep for the 5ms TPM_TIMEOUT */
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#define TPM_TIMEOUT_US_LOW (TPM_TIMEOUT * 1000)
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#define TPM_TIMEOUT_US_HI (TPM_TIMEOUT_US_LOW + 2000)
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/* expected value for DIDVID register */
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#define TPM_TIS_I2C_DID_VID_9635 0xd1150b00L
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#define TPM_TIS_I2C_DID_VID_9645 0x001a15d1L
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enum i2c_chip_type {
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SLB9635,
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SLB9645,
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UNKNOWN,
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};
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/* Structure to store I2C TPM specific stuff */
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struct tpm_inf_dev {
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struct i2c_client *client;
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int locality;
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u8 buf[TPM_BUFSIZE + sizeof(u8)]; /* max. buffer size + addr */
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struct tpm_chip *chip;
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enum i2c_chip_type chip_type;
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unsigned int adapterlimit;
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};
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static struct tpm_inf_dev tpm_dev;
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/*
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* iic_tpm_read() - read from TPM register
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* @addr: register address to read from
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* @buffer: provided by caller
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* @len: number of bytes to read
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*
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* Read len bytes from TPM register and put them into
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* buffer (little-endian format, i.e. first byte is put into buffer[0]).
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*
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* NOTE: TPM is big-endian for multi-byte values. Multi-byte
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* values have to be swapped.
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*
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* NOTE: We can't unfortunately use the combined read/write functions
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* provided by the i2c core as the TPM currently does not support the
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* repeated start condition and due to it's special requirements.
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* The i2c_smbus* functions do not work for this chip.
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*
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* Return -EIO on error, 0 on success.
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*/
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static int iic_tpm_read(u8 addr, u8 *buffer, size_t len)
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{
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struct i2c_msg msg1 = {
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.addr = tpm_dev.client->addr,
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.len = 1,
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.buf = &addr
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};
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struct i2c_msg msg2 = {
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.addr = tpm_dev.client->addr,
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.flags = I2C_M_RD,
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.len = len,
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.buf = buffer
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};
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struct i2c_msg msgs[] = {msg1, msg2};
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int rc = 0;
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int count;
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unsigned int msglen = len;
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/* Lock the adapter for the duration of the whole sequence. */
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if (!tpm_dev.client->adapter->algo->master_xfer)
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return -EOPNOTSUPP;
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i2c_lock_adapter(tpm_dev.client->adapter);
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if (tpm_dev.chip_type == SLB9645) {
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/* use a combined read for newer chips
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* unfortunately the smbus functions are not suitable due to
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* the 32 byte limit of the smbus.
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* retries should usually not be needed, but are kept just to
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* be on the safe side.
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*/
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for (count = 0; count < MAX_COUNT; count++) {
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rc = __i2c_transfer(tpm_dev.client->adapter, msgs, 2);
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if (rc > 0)
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break; /* break here to skip sleep */
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usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI);
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}
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} else {
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/* Expect to send one command message and one data message, but
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* support looping over each or both if necessary.
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*/
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while (len > 0) {
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/* slb9635 protocol should work in all cases */
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for (count = 0; count < MAX_COUNT; count++) {
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rc = __i2c_transfer(tpm_dev.client->adapter,
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&msg1, 1);
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if (rc > 0)
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break; /* break here to skip sleep */
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usleep_range(SLEEP_DURATION_LOW,
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SLEEP_DURATION_HI);
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}
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if (rc <= 0)
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goto out;
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/* After the TPM has successfully received the register
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* address it needs some time, thus we're sleeping here
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* again, before retrieving the data
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*/
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for (count = 0; count < MAX_COUNT; count++) {
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if (tpm_dev.adapterlimit) {
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msglen = min_t(unsigned int,
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tpm_dev.adapterlimit,
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len);
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msg2.len = msglen;
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}
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usleep_range(SLEEP_DURATION_LOW,
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SLEEP_DURATION_HI);
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rc = __i2c_transfer(tpm_dev.client->adapter,
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&msg2, 1);
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if (rc > 0) {
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/* Since len is unsigned, make doubly
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* sure we do not underflow it.
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*/
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if (msglen > len)
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len = 0;
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else
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len -= msglen;
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msg2.buf += msglen;
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break;
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}
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/* If the I2C adapter rejected the request (e.g
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* when the quirk read_max_len < len) fall back
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* to a sane minimum value and try again.
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*/
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if (rc == -EOPNOTSUPP)
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tpm_dev.adapterlimit =
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I2C_SMBUS_BLOCK_MAX;
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}
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if (rc <= 0)
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goto out;
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}
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}
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out:
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i2c_unlock_adapter(tpm_dev.client->adapter);
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/* take care of 'guard time' */
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usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI);
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/* __i2c_transfer returns the number of successfully transferred
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* messages.
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* So rc should be greater than 0 here otherwise we have an error.
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*/
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if (rc <= 0)
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return -EIO;
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return 0;
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}
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static int iic_tpm_write_generic(u8 addr, u8 *buffer, size_t len,
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unsigned int sleep_low,
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unsigned int sleep_hi, u8 max_count)
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{
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int rc = -EIO;
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int count;
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struct i2c_msg msg1 = {
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.addr = tpm_dev.client->addr,
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.len = len + 1,
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.buf = tpm_dev.buf
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};
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if (len > TPM_BUFSIZE)
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return -EINVAL;
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if (!tpm_dev.client->adapter->algo->master_xfer)
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return -EOPNOTSUPP;
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i2c_lock_adapter(tpm_dev.client->adapter);
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/* prepend the 'register address' to the buffer */
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tpm_dev.buf[0] = addr;
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memcpy(&(tpm_dev.buf[1]), buffer, len);
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/*
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* NOTE: We have to use these special mechanisms here and unfortunately
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* cannot rely on the standard behavior of i2c_transfer.
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* Even for newer chips the smbus functions are not
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* suitable due to the 32 byte limit of the smbus.
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*/
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for (count = 0; count < max_count; count++) {
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rc = __i2c_transfer(tpm_dev.client->adapter, &msg1, 1);
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if (rc > 0)
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break;
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usleep_range(sleep_low, sleep_hi);
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}
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i2c_unlock_adapter(tpm_dev.client->adapter);
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/* take care of 'guard time' */
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usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI);
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/* __i2c_transfer returns the number of successfully transferred
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* messages.
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* So rc should be greater than 0 here otherwise we have an error.
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*/
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if (rc <= 0)
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return -EIO;
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return 0;
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}
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/*
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* iic_tpm_write() - write to TPM register
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* @addr: register address to write to
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* @buffer: containing data to be written
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* @len: number of bytes to write
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*
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* Write len bytes from provided buffer to TPM register (little
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* endian format, i.e. buffer[0] is written as first byte).
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*
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* NOTE: TPM is big-endian for multi-byte values. Multi-byte
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* values have to be swapped.
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*
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* NOTE: use this function instead of the iic_tpm_write_generic function.
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*
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* Return -EIO on error, 0 on success
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*/
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static int iic_tpm_write(u8 addr, u8 *buffer, size_t len)
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{
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return iic_tpm_write_generic(addr, buffer, len, SLEEP_DURATION_LOW,
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SLEEP_DURATION_HI, MAX_COUNT);
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}
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/*
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* This function is needed especially for the cleanup situation after
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* sending TPM_READY
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* */
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static int iic_tpm_write_long(u8 addr, u8 *buffer, size_t len)
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{
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return iic_tpm_write_generic(addr, buffer, len, SLEEP_DURATION_LONG_LOW,
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SLEEP_DURATION_LONG_HI, MAX_COUNT_LONG);
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}
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enum tis_access {
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TPM_ACCESS_VALID = 0x80,
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TPM_ACCESS_ACTIVE_LOCALITY = 0x20,
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TPM_ACCESS_REQUEST_PENDING = 0x04,
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TPM_ACCESS_REQUEST_USE = 0x02,
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};
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enum tis_status {
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TPM_STS_VALID = 0x80,
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TPM_STS_COMMAND_READY = 0x40,
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TPM_STS_GO = 0x20,
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TPM_STS_DATA_AVAIL = 0x10,
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TPM_STS_DATA_EXPECT = 0x08,
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};
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enum tis_defaults {
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TIS_SHORT_TIMEOUT = 750, /* ms */
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TIS_LONG_TIMEOUT = 2000, /* 2 sec */
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};
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#define TPM_ACCESS(l) (0x0000 | ((l) << 4))
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#define TPM_STS(l) (0x0001 | ((l) << 4))
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#define TPM_DATA_FIFO(l) (0x0005 | ((l) << 4))
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#define TPM_DID_VID(l) (0x0006 | ((l) << 4))
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static bool check_locality(struct tpm_chip *chip, int loc)
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{
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u8 buf;
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int rc;
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rc = iic_tpm_read(TPM_ACCESS(loc), &buf, 1);
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if (rc < 0)
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return false;
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if ((buf & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
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(TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) {
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tpm_dev.locality = loc;
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return true;
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}
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return false;
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}
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/* implementation similar to tpm_tis */
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static void release_locality(struct tpm_chip *chip, int loc, int force)
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{
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u8 buf;
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if (iic_tpm_read(TPM_ACCESS(loc), &buf, 1) < 0)
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return;
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if (force || (buf & (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) ==
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(TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) {
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buf = TPM_ACCESS_ACTIVE_LOCALITY;
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iic_tpm_write(TPM_ACCESS(loc), &buf, 1);
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}
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}
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static int request_locality(struct tpm_chip *chip, int loc)
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{
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unsigned long stop;
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u8 buf = TPM_ACCESS_REQUEST_USE;
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if (check_locality(chip, loc))
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return loc;
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iic_tpm_write(TPM_ACCESS(loc), &buf, 1);
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/* wait for burstcount */
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stop = jiffies + chip->timeout_a;
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do {
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if (check_locality(chip, loc))
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return loc;
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usleep_range(TPM_TIMEOUT_US_LOW, TPM_TIMEOUT_US_HI);
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} while (time_before(jiffies, stop));
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return -ETIME;
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}
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static u8 tpm_tis_i2c_status(struct tpm_chip *chip)
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{
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/* NOTE: since I2C read may fail, return 0 in this case --> time-out */
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u8 buf = 0xFF;
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u8 i = 0;
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do {
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if (iic_tpm_read(TPM_STS(tpm_dev.locality), &buf, 1) < 0)
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return 0;
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i++;
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/* if locallity is set STS should not be 0xFF */
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} while ((buf == 0xFF) && i < 10);
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return buf;
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}
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static void tpm_tis_i2c_ready(struct tpm_chip *chip)
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{
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/* this causes the current command to be aborted */
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u8 buf = TPM_STS_COMMAND_READY;
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iic_tpm_write_long(TPM_STS(tpm_dev.locality), &buf, 1);
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}
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static ssize_t get_burstcount(struct tpm_chip *chip)
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{
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unsigned long stop;
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ssize_t burstcnt;
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u8 buf[3];
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/* wait for burstcount */
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/* which timeout value, spec has 2 answers (c & d) */
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stop = jiffies + chip->timeout_d;
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do {
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/* Note: STS is little endian */
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if (iic_tpm_read(TPM_STS(tpm_dev.locality)+1, buf, 3) < 0)
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burstcnt = 0;
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else
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burstcnt = (buf[2] << 16) + (buf[1] << 8) + buf[0];
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if (burstcnt)
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return burstcnt;
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usleep_range(TPM_TIMEOUT_US_LOW, TPM_TIMEOUT_US_HI);
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} while (time_before(jiffies, stop));
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return -EBUSY;
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}
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static int wait_for_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
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int *status)
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{
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unsigned long stop;
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/* check current status */
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*status = tpm_tis_i2c_status(chip);
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if ((*status != 0xFF) && (*status & mask) == mask)
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return 0;
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stop = jiffies + timeout;
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do {
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/* since we just checked the status, give the TPM some time */
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usleep_range(TPM_TIMEOUT_US_LOW, TPM_TIMEOUT_US_HI);
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*status = tpm_tis_i2c_status(chip);
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if ((*status & mask) == mask)
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return 0;
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} while (time_before(jiffies, stop));
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return -ETIME;
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}
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static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
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{
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size_t size = 0;
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ssize_t burstcnt;
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u8 retries = 0;
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int rc;
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while (size < count) {
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burstcnt = get_burstcount(chip);
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/* burstcnt < 0 = TPM is busy */
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if (burstcnt < 0)
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return burstcnt;
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/* limit received data to max. left */
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if (burstcnt > (count - size))
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burstcnt = count - size;
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rc = iic_tpm_read(TPM_DATA_FIFO(tpm_dev.locality),
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&(buf[size]), burstcnt);
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if (rc == 0)
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size += burstcnt;
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else if (rc < 0)
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retries++;
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/* avoid endless loop in case of broken HW */
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if (retries > MAX_COUNT_LONG)
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return -EIO;
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}
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return size;
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}
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static int tpm_tis_i2c_recv(struct tpm_chip *chip, u8 *buf, size_t count)
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{
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int size = 0;
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int status;
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u32 expected;
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if (count < TPM_HEADER_SIZE) {
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size = -EIO;
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goto out;
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}
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/* read first 10 bytes, including tag, paramsize, and result */
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size = recv_data(chip, buf, TPM_HEADER_SIZE);
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if (size < TPM_HEADER_SIZE) {
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dev_err(&chip->dev, "Unable to read header\n");
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goto out;
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}
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expected = be32_to_cpu(*(__be32 *)(buf + 2));
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if (((size_t) expected > count) || (expected < TPM_HEADER_SIZE)) {
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size = -EIO;
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goto out;
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}
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size += recv_data(chip, &buf[TPM_HEADER_SIZE],
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expected - TPM_HEADER_SIZE);
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if (size < expected) {
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dev_err(&chip->dev, "Unable to read remainder of result\n");
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size = -ETIME;
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goto out;
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}
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wait_for_stat(chip, TPM_STS_VALID, chip->timeout_c, &status);
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if (status & TPM_STS_DATA_AVAIL) { /* retry? */
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dev_err(&chip->dev, "Error left over data\n");
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size = -EIO;
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goto out;
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}
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out:
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tpm_tis_i2c_ready(chip);
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/* The TPM needs some time to clean up here,
|
|
* so we sleep rather than keeping the bus busy
|
|
*/
|
|
usleep_range(SLEEP_DURATION_RESET_LOW, SLEEP_DURATION_RESET_HI);
|
|
release_locality(chip, tpm_dev.locality, 0);
|
|
return size;
|
|
}
|
|
|
|
static int tpm_tis_i2c_send(struct tpm_chip *chip, u8 *buf, size_t len)
|
|
{
|
|
int rc, status;
|
|
ssize_t burstcnt;
|
|
size_t count = 0;
|
|
u8 retries = 0;
|
|
u8 sts = TPM_STS_GO;
|
|
|
|
if (len > TPM_BUFSIZE)
|
|
return -E2BIG; /* command is too long for our tpm, sorry */
|
|
|
|
if (request_locality(chip, 0) < 0)
|
|
return -EBUSY;
|
|
|
|
status = tpm_tis_i2c_status(chip);
|
|
if ((status & TPM_STS_COMMAND_READY) == 0) {
|
|
tpm_tis_i2c_ready(chip);
|
|
if (wait_for_stat
|
|
(chip, TPM_STS_COMMAND_READY,
|
|
chip->timeout_b, &status) < 0) {
|
|
rc = -ETIME;
|
|
goto out_err;
|
|
}
|
|
}
|
|
|
|
while (count < len - 1) {
|
|
burstcnt = get_burstcount(chip);
|
|
|
|
/* burstcnt < 0 = TPM is busy */
|
|
if (burstcnt < 0)
|
|
return burstcnt;
|
|
|
|
if (burstcnt > (len - 1 - count))
|
|
burstcnt = len - 1 - count;
|
|
|
|
rc = iic_tpm_write(TPM_DATA_FIFO(tpm_dev.locality),
|
|
&(buf[count]), burstcnt);
|
|
if (rc == 0)
|
|
count += burstcnt;
|
|
else if (rc < 0)
|
|
retries++;
|
|
|
|
/* avoid endless loop in case of broken HW */
|
|
if (retries > MAX_COUNT_LONG) {
|
|
rc = -EIO;
|
|
goto out_err;
|
|
}
|
|
|
|
wait_for_stat(chip, TPM_STS_VALID,
|
|
chip->timeout_c, &status);
|
|
|
|
if ((status & TPM_STS_DATA_EXPECT) == 0) {
|
|
rc = -EIO;
|
|
goto out_err;
|
|
}
|
|
}
|
|
|
|
/* write last byte */
|
|
iic_tpm_write(TPM_DATA_FIFO(tpm_dev.locality), &(buf[count]), 1);
|
|
wait_for_stat(chip, TPM_STS_VALID, chip->timeout_c, &status);
|
|
if ((status & TPM_STS_DATA_EXPECT) != 0) {
|
|
rc = -EIO;
|
|
goto out_err;
|
|
}
|
|
|
|
/* go and do it */
|
|
iic_tpm_write(TPM_STS(tpm_dev.locality), &sts, 1);
|
|
|
|
return len;
|
|
out_err:
|
|
tpm_tis_i2c_ready(chip);
|
|
/* The TPM needs some time to clean up here,
|
|
* so we sleep rather than keeping the bus busy
|
|
*/
|
|
usleep_range(SLEEP_DURATION_RESET_LOW, SLEEP_DURATION_RESET_HI);
|
|
release_locality(chip, tpm_dev.locality, 0);
|
|
return rc;
|
|
}
|
|
|
|
static bool tpm_tis_i2c_req_canceled(struct tpm_chip *chip, u8 status)
|
|
{
|
|
return (status == TPM_STS_COMMAND_READY);
|
|
}
|
|
|
|
static const struct tpm_class_ops tpm_tis_i2c = {
|
|
.flags = TPM_OPS_AUTO_STARTUP,
|
|
.status = tpm_tis_i2c_status,
|
|
.recv = tpm_tis_i2c_recv,
|
|
.send = tpm_tis_i2c_send,
|
|
.cancel = tpm_tis_i2c_ready,
|
|
.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
|
|
.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
|
|
.req_canceled = tpm_tis_i2c_req_canceled,
|
|
};
|
|
|
|
static int tpm_tis_i2c_init(struct device *dev)
|
|
{
|
|
u32 vendor;
|
|
int rc = 0;
|
|
struct tpm_chip *chip;
|
|
|
|
chip = tpmm_chip_alloc(dev, &tpm_tis_i2c);
|
|
if (IS_ERR(chip))
|
|
return PTR_ERR(chip);
|
|
|
|
/* Default timeouts */
|
|
chip->timeout_a = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
|
|
chip->timeout_b = msecs_to_jiffies(TIS_LONG_TIMEOUT);
|
|
chip->timeout_c = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
|
|
chip->timeout_d = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
|
|
|
|
if (request_locality(chip, 0) != 0) {
|
|
dev_err(dev, "could not request locality\n");
|
|
rc = -ENODEV;
|
|
goto out_err;
|
|
}
|
|
|
|
/* read four bytes from DID_VID register */
|
|
if (iic_tpm_read(TPM_DID_VID(0), (u8 *)&vendor, 4) < 0) {
|
|
dev_err(dev, "could not read vendor id\n");
|
|
rc = -EIO;
|
|
goto out_release;
|
|
}
|
|
|
|
if (vendor == TPM_TIS_I2C_DID_VID_9645) {
|
|
tpm_dev.chip_type = SLB9645;
|
|
} else if (vendor == TPM_TIS_I2C_DID_VID_9635) {
|
|
tpm_dev.chip_type = SLB9635;
|
|
} else {
|
|
dev_err(dev, "vendor id did not match! ID was %08x\n", vendor);
|
|
rc = -ENODEV;
|
|
goto out_release;
|
|
}
|
|
|
|
dev_info(dev, "1.2 TPM (device-id 0x%X)\n", vendor >> 16);
|
|
|
|
tpm_dev.chip = chip;
|
|
|
|
return tpm_chip_register(chip);
|
|
out_release:
|
|
release_locality(chip, tpm_dev.locality, 1);
|
|
tpm_dev.client = NULL;
|
|
out_err:
|
|
return rc;
|
|
}
|
|
|
|
static const struct i2c_device_id tpm_tis_i2c_table[] = {
|
|
{"tpm_i2c_infineon"},
|
|
{"slb9635tt"},
|
|
{"slb9645tt"},
|
|
{},
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(i2c, tpm_tis_i2c_table);
|
|
|
|
#ifdef CONFIG_OF
|
|
static const struct of_device_id tpm_tis_i2c_of_match[] = {
|
|
{.compatible = "infineon,tpm_i2c_infineon"},
|
|
{.compatible = "infineon,slb9635tt"},
|
|
{.compatible = "infineon,slb9645tt"},
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, tpm_tis_i2c_of_match);
|
|
#endif
|
|
|
|
static SIMPLE_DEV_PM_OPS(tpm_tis_i2c_ops, tpm_pm_suspend, tpm_pm_resume);
|
|
|
|
static int tpm_tis_i2c_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
int rc;
|
|
struct device *dev = &(client->dev);
|
|
|
|
if (tpm_dev.client != NULL) {
|
|
dev_err(dev, "This driver only supports one client at a time\n");
|
|
return -EBUSY; /* We only support one client */
|
|
}
|
|
|
|
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
|
|
dev_err(dev, "no algorithms associated to the i2c bus\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
tpm_dev.client = client;
|
|
rc = tpm_tis_i2c_init(&client->dev);
|
|
if (rc != 0) {
|
|
tpm_dev.client = NULL;
|
|
rc = -ENODEV;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
static int tpm_tis_i2c_remove(struct i2c_client *client)
|
|
{
|
|
struct tpm_chip *chip = tpm_dev.chip;
|
|
|
|
tpm_chip_unregister(chip);
|
|
release_locality(chip, tpm_dev.locality, 1);
|
|
tpm_dev.client = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct i2c_driver tpm_tis_i2c_driver = {
|
|
.id_table = tpm_tis_i2c_table,
|
|
.probe = tpm_tis_i2c_probe,
|
|
.remove = tpm_tis_i2c_remove,
|
|
.driver = {
|
|
.name = "tpm_i2c_infineon",
|
|
.pm = &tpm_tis_i2c_ops,
|
|
.of_match_table = of_match_ptr(tpm_tis_i2c_of_match),
|
|
},
|
|
};
|
|
|
|
module_i2c_driver(tpm_tis_i2c_driver);
|
|
MODULE_AUTHOR("Peter Huewe <peter.huewe@infineon.com>");
|
|
MODULE_DESCRIPTION("TPM TIS I2C Infineon Driver");
|
|
MODULE_VERSION("2.2.0");
|
|
MODULE_LICENSE("GPL");
|