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735 lines
18 KiB
735 lines
18 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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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 <[email protected]> |
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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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#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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|
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#define TPM_I2C_INFINEON_BUFSIZE 1260 |
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|
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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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|
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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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|
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#define SLEEP_DURATION_LONG_LOW 200 |
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#define SLEEP_DURATION_LONG_HI 220 |
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|
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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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|
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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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struct tpm_inf_dev { |
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struct i2c_client *client; |
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int locality; |
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/* In addition to the data itself, the buffer must fit the 7-bit I2C |
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* address and the direction bit. |
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*/ |
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u8 buf[TPM_I2C_INFINEON_BUFSIZE + 1]; |
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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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/* |
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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_bus(tpm_dev.client->adapter, I2C_LOCK_SEGMENT); |
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|
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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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|
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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_bus(tpm_dev.client->adapter, I2C_LOCK_SEGMENT); |
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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_I2C_INFINEON_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_bus(tpm_dev.client->adapter, I2C_LOCK_SEGMENT); |
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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_bus(tpm_dev.client->adapter, I2C_LOCK_SEGMENT); |
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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} while (time_before(jiffies, stop)); |
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|
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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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|
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while (size < count) { |
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burstcnt = get_burstcount(chip); |
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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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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|
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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, |
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* so we sleep rather than keeping the bus busy |
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*/ |
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usleep_range(SLEEP_DURATION_RESET_LOW, SLEEP_DURATION_RESET_HI); |
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release_locality(chip, tpm_dev.locality, 0); |
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return size; |
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} |
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|
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static int tpm_tis_i2c_send(struct tpm_chip *chip, u8 *buf, size_t len) |
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{ |
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int rc, status; |
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ssize_t burstcnt; |
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size_t count = 0; |
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u8 retries = 0; |
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u8 sts = TPM_STS_GO; |
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|
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if (len > TPM_I2C_INFINEON_BUFSIZE) |
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return -E2BIG; |
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if (request_locality(chip, 0) < 0) |
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return -EBUSY; |
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status = tpm_tis_i2c_status(chip); |
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if ((status & TPM_STS_COMMAND_READY) == 0) { |
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tpm_tis_i2c_ready(chip); |
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if (wait_for_stat |
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(chip, TPM_STS_COMMAND_READY, |
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chip->timeout_b, &status) < 0) { |
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rc = -ETIME; |
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goto out_err; |
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} |
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} |
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|
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while (count < len - 1) { |
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burstcnt = get_burstcount(chip); |
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|
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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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|
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if (burstcnt > (len - 1 - count)) |
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burstcnt = len - 1 - count; |
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|
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rc = iic_tpm_write(TPM_DATA_FIFO(tpm_dev.locality), |
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&(buf[count]), burstcnt); |
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if (rc == 0) |
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count += burstcnt; |
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else if (rc < 0) |
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retries++; |
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|
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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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rc = -EIO; |
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goto out_err; |
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} |
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|
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wait_for_stat(chip, TPM_STS_VALID, |
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chip->timeout_c, &status); |
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|
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if ((status & TPM_STS_DATA_EXPECT) == 0) { |
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rc = -EIO; |
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goto out_err; |
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} |
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} |
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|
|
/* 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 0; |
|
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 <[email protected]>"); |
|
MODULE_DESCRIPTION("TPM TIS I2C Infineon Driver"); |
|
MODULE_VERSION("2.2.0"); |
|
MODULE_LICENSE("GPL");
|
|
|