- 根目录:
- drivers
- char
- tpm
- tpm_i2c_stm_st33.c
/*
* STMicroelectronics TPM I2C Linux driver for TPM ST33ZP24
* Copyright (C) 2009, 2010 STMicroelectronics
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* STMicroelectronics version 1.2.0, Copyright (C) 2010
* STMicroelectronics comes with ABSOLUTELY NO WARRANTY.
* This is free software, and you are welcome to redistribute it
* under certain conditions.
*
* @Author: Christophe RICARD tpmsupport@st.com
*
* @File: tpm_stm_st33_i2c.c
*
* @Synopsis:
* 09/15/2010: First shot driver tpm_tis driver for
lpc is used as model.
*/
#include <linux/pci.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/i2c.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/wait.h>
#include <linux/string.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/sysfs.h>
#include <linux/gpio.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <linux/slab.h>
#include "tpm.h"
#include "tpm_i2c_stm_st33.h"
enum stm33zp24_access {
TPM_ACCESS_VALID = 0x80,
TPM_ACCESS_ACTIVE_LOCALITY = 0x20,
TPM_ACCESS_REQUEST_PENDING = 0x04,
TPM_ACCESS_REQUEST_USE = 0x02,
};
enum stm33zp24_status {
TPM_STS_VALID = 0x80,
TPM_STS_COMMAND_READY = 0x40,
TPM_STS_GO = 0x20,
TPM_STS_DATA_AVAIL = 0x10,
TPM_STS_DATA_EXPECT = 0x08,
};
enum stm33zp24_int_flags {
TPM_GLOBAL_INT_ENABLE = 0x80,
TPM_INTF_CMD_READY_INT = 0x080,
TPM_INTF_FIFO_AVALAIBLE_INT = 0x040,
TPM_INTF_WAKE_UP_READY_INT = 0x020,
TPM_INTF_LOCALITY_CHANGE_INT = 0x004,
TPM_INTF_STS_VALID_INT = 0x002,
TPM_INTF_DATA_AVAIL_INT = 0x001,
};
enum tis_defaults {
TIS_SHORT_TIMEOUT = 750,
TIS_LONG_TIMEOUT = 2000,
};
/*
* write8_reg
* Send byte to the TIS register according to the ST33ZP24 I2C protocol.
* @param: tpm_register, the tpm tis register where the data should be written
* @param: tpm_data, the tpm_data to write inside the tpm_register
* @param: tpm_size, The length of the data
* @return: Returns negative errno, or else the number of bytes written.
*/
static int write8_reg(struct i2c_client *client, u8 tpm_register,
u8 *tpm_data, u16 tpm_size)
{
struct st33zp24_platform_data *pin_infos;
pin_infos = client->dev.platform_data;
pin_infos->tpm_i2c_buffer[0][0] = tpm_register;
memcpy(&pin_infos->tpm_i2c_buffer[0][1], tpm_data, tpm_size);
return i2c_master_send(client, pin_infos->tpm_i2c_buffer[0],
tpm_size + 1);
} /* write8_reg() */
/*
* read8_reg
* Recv byte from the TIS register according to the ST33ZP24 I2C protocol.
* @param: tpm_register, the tpm tis register where the data should be read
* @param: tpm_data, the TPM response
* @param: tpm_size, tpm TPM response size to read.
* @return: number of byte read successfully: should be one if success.
*/
static int read8_reg(struct i2c_client *client, u8 tpm_register,
u8 *tpm_data, int tpm_size)
{
u8 status = 0;
u8 data;
data = TPM_DUMMY_BYTE;
status = write8_reg(client, tpm_register, &data, 1);
if (status == 2)
status = i2c_master_recv(client, tpm_data, tpm_size);
return status;
} /* read8_reg() */
/*
* I2C_WRITE_DATA
* Send byte to the TIS register according to the ST33ZP24 I2C protocol.
* @param: client, the chip description
* @param: tpm_register, the tpm tis register where the data should be written
* @param: tpm_data, the tpm_data to write inside the tpm_register
* @param: tpm_size, The length of the data
* @return: number of byte written successfully: should be one if success.
*/
#define I2C_WRITE_DATA(client, tpm_register, tpm_data, tpm_size) \
(write8_reg(client, tpm_register | \
TPM_WRITE_DIRECTION, tpm_data, tpm_size))
/*
* I2C_READ_DATA
* Recv byte from the TIS register according to the ST33ZP24 I2C protocol.
* @param: tpm, the chip description
* @param: tpm_register, the tpm tis register where the data should be read
* @param: tpm_data, the TPM response
* @param: tpm_size, tpm TPM response size to read.
* @return: number of byte read successfully: should be one if success.
*/
#define I2C_READ_DATA(client, tpm_register, tpm_data, tpm_size) \
(read8_reg(client, tpm_register, tpm_data, tpm_size))
/*
* clear_interruption
* clear the TPM interrupt register.
* @param: tpm, the chip description
*/
static void clear_interruption(struct i2c_client *client)
{
u8 interrupt;
I2C_READ_DATA(client, TPM_INT_STATUS, &interrupt, 1);
I2C_WRITE_DATA(client, TPM_INT_STATUS, &interrupt, 1);
I2C_READ_DATA(client, TPM_INT_STATUS, &interrupt, 1);
} /* clear_interruption() */
/*
* _wait_for_interrupt_serirq_timeout
* @param: tpm, the chip description
* @param: timeout, the timeout of the interrupt
* @return: the status of the interruption.
*/
static long _wait_for_interrupt_serirq_timeout(struct tpm_chip *chip,
unsigned long timeout)
{
long status;
struct i2c_client *client;
struct st33zp24_platform_data *pin_infos;
client = (struct i2c_client *)TPM_VPRIV(chip);
pin_infos = client->dev.platform_data;
status = wait_for_completion_interruptible_timeout(
&pin_infos->irq_detection,
timeout);
if (status > 0)
enable_irq(gpio_to_irq(pin_infos->io_serirq));
gpio_direction_input(pin_infos->io_serirq);
return status;
} /* wait_for_interrupt_serirq_timeout() */
static int wait_for_serirq_timeout(struct tpm_chip *chip, bool condition,
unsigned long timeout)
{
int status = 2;
struct i2c_client *client;
client = (struct i2c_client *)TPM_VPRIV(chip);
status = _wait_for_interrupt_serirq_timeout(chip, timeout);
if (!status) {
status = -EBUSY;
} else {
clear_interruption(client);
if (condition)
status = 1;
}
return status;
}
/*
* tpm_stm_i2c_cancel, cancel is not implemented.
* @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h
*/
static void tpm_stm_i2c_cancel(struct tpm_chip *chip)
{
struct i2c_client *client;
u8 data;
client = (struct i2c_client *)TPM_VPRIV(chip);
data = TPM_STS_COMMAND_READY;
I2C_WRITE_DATA(client, TPM_STS, &data, 1);
if (chip->vendor.irq)
wait_for_serirq_timeout(chip, 1, chip->vendor.timeout_a);
} /* tpm_stm_i2c_cancel() */
/*
* tpm_stm_spi_status return the TPM_STS register
* @param: chip, the tpm chip description
* @return: the TPM_STS register value.
*/
static u8 tpm_stm_i2c_status(struct tpm_chip *chip)
{
struct i2c_client *client;
u8 data;
client = (struct i2c_client *)TPM_VPRIV(chip);
I2C_READ_DATA(client, TPM_STS, &data, 1);
return data;
} /* tpm_stm_i2c_status() */
/*
* check_locality if the locality is active
* @param: chip, the tpm chip description
* @return: the active locality or -EACCESS.
*/
static int check_locality(struct tpm_chip *chip)
{
struct i2c_client *client;
u8 data;
u8 status;
client = (struct i2c_client *)TPM_VPRIV(chip);
status = I2C_READ_DATA(client, TPM_ACCESS, &data, 1);
if (status && (data &
(TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
(TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
return chip->vendor.locality;
return -EACCES;
} /* check_locality() */
/*
* request_locality request the TPM locality
* @param: chip, the chip description
* @return: the active locality or EACCESS.
*/
static int request_locality(struct tpm_chip *chip)
{
unsigned long stop;
long rc;
struct i2c_client *client;
u8 data;
client = (struct i2c_client *)TPM_VPRIV(chip);
if (check_locality(chip) == chip->vendor.locality)
return chip->vendor.locality;
data = TPM_ACCESS_REQUEST_USE;
rc = I2C_WRITE_DATA(client, TPM_ACCESS, &data, 1);
if (rc < 0)
goto end;
if (chip->vendor.irq) {
rc = wait_for_serirq_timeout(chip, (check_locality
(chip) >= 0),
chip->vendor.timeout_a);
if (rc > 0)
return chip->vendor.locality;
} else {
stop = jiffies + chip->vendor.timeout_a;
do {
if (check_locality(chip) >= 0)
return chip->vendor.locality;
msleep(TPM_TIMEOUT);
} while (time_before(jiffies, stop));
}
rc = -EACCES;
end:
return rc;
} /* request_locality() */
/*
* release_locality release the active locality
* @param: chip, the tpm chip description.
*/
static void release_locality(struct tpm_chip *chip)
{
struct i2c_client *client;
u8 data;
client = (struct i2c_client *)TPM_VPRIV(chip);
data = TPM_ACCESS_ACTIVE_LOCALITY;
I2C_WRITE_DATA(client, TPM_ACCESS, &data, 1);
}
/*
* get_burstcount return the burstcount address 0x19 0x1A
* @param: chip, the chip description
* return: the burstcount.
*/
static int get_burstcount(struct tpm_chip *chip)
{
unsigned long stop;
int burstcnt, status;
u8 tpm_reg, temp;
struct i2c_client *client = (struct i2c_client *)TPM_VPRIV(chip);
stop = jiffies + chip->vendor.timeout_d;
do {
tpm_reg = TPM_STS + 1;
status = I2C_READ_DATA(client, tpm_reg, &temp, 1);
if (status < 0)
goto end;
tpm_reg = tpm_reg + 1;
burstcnt = temp;
status = I2C_READ_DATA(client, tpm_reg, &temp, 1);
if (status < 0)
goto end;
burstcnt |= temp << 8;
if (burstcnt)
return burstcnt;
msleep(TPM_TIMEOUT);
} while (time_before(jiffies, stop));
end:
return -EBUSY;
} /* get_burstcount() */
/*
* wait_for_stat wait for a TPM_STS value
* @param: chip, the tpm chip description
* @param: mask, the value mask to wait
* @param: timeout, the timeout
* @param: queue, the wait queue.
* @return: the tpm status, 0 if success, -ETIME if timeout is reached.
*/
static int wait_for_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
wait_queue_head_t *queue)
{
unsigned long stop;
long rc;
u8 status;
if (chip->vendor.irq) {
rc = wait_for_serirq_timeout(chip, ((tpm_stm_i2c_status
(chip) & mask) ==
mask), timeout);
if (rc > 0)
return 0;
} else {
stop = jiffies + timeout;
do {
msleep(TPM_TIMEOUT);
status = tpm_stm_i2c_status(chip);
if ((status & mask) == mask)
return 0;
} while (time_before(jiffies, stop));
}
return -ETIME;
} /* wait_for_stat() */
/*
* recv_data receive data
* @param: chip, the tpm chip description
* @param: buf, the buffer where the data are received
* @param: count, the number of data to receive
* @return: the number of bytes read from TPM FIFO.
*/
static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
{
int size = 0, burstcnt, len;
struct i2c_client *client;
client = (struct i2c_client *)TPM_VPRIV(chip);
while (size < count &&
wait_for_stat(chip,
TPM_STS_DATA_AVAIL | TPM_STS_VALID,
chip->vendor.timeout_c,
&chip->vendor.read_queue)
== 0) {
burstcnt = get_burstcount(chip);
len = min_t(int, burstcnt, count - size);
I2C_READ_DATA(client, TPM_DATA_FIFO, buf + size, len);
size += len;
}
return size;
}
/*
* tpm_ioserirq_handler the serirq irq handler
* @param: irq, the tpm chip description
* @param: dev_id, the description of the chip
* @return: the status of the handler.
*/
static irqreturn_t tpm_ioserirq_handler(int irq, void *dev_id)
{
struct tpm_chip *chip = dev_id;
struct i2c_client *client;
struct st33zp24_platform_data *pin_infos;
disable_irq_nosync(irq);
client = (struct i2c_client *)TPM_VPRIV(chip);
pin_infos = client->dev.platform_data;
complete(&pin_infos->irq_detection);
return IRQ_HANDLED;
} /* tpm_ioserirq_handler() */
/*
* tpm_stm_i2c_send send TPM commands through the I2C bus.
*
* @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h
* @param: buf, the buffer to send.
* @param: count, the number of bytes to send.
* @return: In case of success the number of bytes sent.
* In other case, a < 0 value describing the issue.
*/
static int tpm_stm_i2c_send(struct tpm_chip *chip, unsigned char *buf,
size_t len)
{
u32 status, burstcnt = 0, i, size;
int ret;
u8 data;
struct i2c_client *client;
if (chip == NULL)
return -EBUSY;
if (len < TPM_HEADER_SIZE)
return -EBUSY;
client = (struct i2c_client *)TPM_VPRIV(chip);
client->flags = 0;
ret = request_locality(chip);
if (ret < 0)
return ret;
status = tpm_stm_i2c_status(chip);
if ((status & TPM_STS_COMMAND_READY) == 0) {
tpm_stm_i2c_cancel(chip);
if (wait_for_stat
(chip, TPM_STS_COMMAND_READY, chip->vendor.timeout_b,
&chip->vendor.int_queue) < 0) {
ret = -ETIME;
goto out_err;
}
}
for (i = 0; i < len - 1;) {
burstcnt = get_burstcount(chip);
size = min_t(int, len - i - 1, burstcnt);
ret = I2C_WRITE_DATA(client, TPM_DATA_FIFO, buf, size);
if (ret < 0)
goto out_err;
i += size;
}
status = tpm_stm_i2c_status(chip);
if ((status & TPM_STS_DATA_EXPECT) == 0) {
ret = -EIO;
goto out_err;
}
ret = I2C_WRITE_DATA(client, TPM_DATA_FIFO, buf + len - 1, 1);
if (ret < 0)
goto out_err;
status = tpm_stm_i2c_status(chip);
if ((status & TPM_STS_DATA_EXPECT) != 0) {
ret = -EIO;
goto out_err;
}
data = TPM_STS_GO;
I2C_WRITE_DATA(client, TPM_STS, &data, 1);
return len;
out_err:
tpm_stm_i2c_cancel(chip);
release_locality(chip);
return ret;
}
/*
* tpm_stm_i2c_recv received TPM response through the I2C bus.
* @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h.
* @param: buf, the buffer to store datas.
* @param: count, the number of bytes to send.
* @return: In case of success the number of bytes received.
* In other case, a < 0 value describing the issue.
*/
static int tpm_stm_i2c_recv(struct tpm_chip *chip, unsigned char *buf,
size_t count)
{
int size = 0;
int expected;
if (chip == NULL)
return -EBUSY;
if (count < TPM_HEADER_SIZE) {
size = -EIO;
goto out;
}
size = recv_data(chip, buf, TPM_HEADER_SIZE);
if (size < TPM_HEADER_SIZE) {
dev_err(chip->dev, "Unable to read header\n");
goto out;
}
expected = be32_to_cpu(*(__be32 *)(buf + 2));
if (expected > count) {
size = -EIO;
goto out;
}
size += recv_data(chip, &buf[TPM_HEADER_SIZE],
expected - TPM_HEADER_SIZE);
if (size < expected) {
dev_err(chip->dev, "Unable to read remainder of result\n");
size = -ETIME;
goto out;
}
out:
chip->vendor.cancel(chip);
release_locality(chip);
return size;
}
static bool tpm_st33_i2c_req_canceled(struct tpm_chip *chip, u8 status)
{
return (status == TPM_STS_COMMAND_READY);
}
static const struct file_operations tpm_st33_i2c_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.read = tpm_read,
.write = tpm_write,
.open = tpm_open,
.release = tpm_release,
};
static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL);
static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL);
static DEVICE_ATTR(enabled, S_IRUGO, tpm_show_enabled, NULL);
static DEVICE_ATTR(active, S_IRUGO, tpm_show_active, NULL);
static DEVICE_ATTR(owned, S_IRUGO, tpm_show_owned, NULL);
static DEVICE_ATTR(temp_deactivated, S_IRUGO, tpm_show_temp_deactivated, NULL);
static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps_1_2, NULL);
static DEVICE_ATTR(cancel, S_IWUSR | S_IWGRP, NULL, tpm_store_cancel);
static struct attribute *stm_tpm_attrs[] = {
&dev_attr_pubek.attr,
&dev_attr_pcrs.attr,
&dev_attr_enabled.attr,
&dev_attr_active.attr,
&dev_attr_owned.attr,
&dev_attr_temp_deactivated.attr,
&dev_attr_caps.attr,
&dev_attr_cancel.attr, NULL,
};
static struct attribute_group stm_tpm_attr_grp = {
.attrs = stm_tpm_attrs
};
static struct tpm_vendor_specific st_i2c_tpm = {
.send = tpm_stm_i2c_send,
.recv = tpm_stm_i2c_recv,
.cancel = tpm_stm_i2c_cancel,
.status = tpm_stm_i2c_status,
.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
.req_canceled = tpm_st33_i2c_req_canceled,
.attr_group = &stm_tpm_attr_grp,
.miscdev = {.fops = &tpm_st33_i2c_fops,},
};
static int interrupts;
module_param(interrupts, int, 0444);
MODULE_PARM_DESC(interrupts, "Enable interrupts");
static int power_mgt = 1;
module_param(power_mgt, int, 0444);
MODULE_PARM_DESC(power_mgt, "Power Management");
/*
* tpm_st33_i2c_probe initialize the TPM device
* @param: client, the i2c_client drescription (TPM I2C description).
* @param: id, the i2c_device_id struct.
* @return: 0 in case of success.
* -1 in other case.
*/
static int
tpm_st33_i2c_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
int err;
u8 intmask;
struct tpm_chip *chip;
struct st33zp24_platform_data *platform_data;
if (client == NULL) {
pr_info("%s: i2c client is NULL. Device not accessible.\n",
__func__);
err = -ENODEV;
goto end;
}
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
dev_info(&client->dev, "client not i2c capable\n");
err = -ENODEV;
goto end;
}
chip = tpm_register_hardware(&client->dev, &st_i2c_tpm);
if (!chip) {
dev_info(&client->dev, "fail chip\n");
err = -ENODEV;
goto end;
}
platform_data = client->dev.platform_data;
if (!platform_data) {
dev_info(&client->dev, "chip not available\n");
err = -ENODEV;
goto _tpm_clean_answer;
}
platform_data->tpm_i2c_buffer[0] =
kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
if (platform_data->tpm_i2c_buffer[0] == NULL) {
err = -ENOMEM;
goto _tpm_clean_answer;
}
platform_data->tpm_i2c_buffer[1] =
kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
if (platform_data->tpm_i2c_buffer[1] == NULL) {
err = -ENOMEM;
goto _tpm_clean_response1;
}
TPM_VPRIV(chip) = client;
chip->vendor.timeout_a = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
chip->vendor.timeout_b = msecs_to_jiffies(TIS_LONG_TIMEOUT);
chip->vendor.timeout_c = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
chip->vendor.timeout_d = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
chip->vendor.locality = LOCALITY0;
if (power_mgt) {
err = gpio_request(platform_data->io_lpcpd, "TPM IO_LPCPD");
if (err)
goto _gpio_init1;
gpio_set_value(platform_data->io_lpcpd, 1);
}
if (interrupts) {
init_completion(&platform_data->irq_detection);
if (request_locality(chip) != LOCALITY0) {
err = -ENODEV;
goto _tpm_clean_response2;
}
err = gpio_request(platform_data->io_serirq, "TPM IO_SERIRQ");
if (err)
goto _gpio_init2;
clear_interruption(client);
err = request_irq(gpio_to_irq(platform_data->io_serirq),
&tpm_ioserirq_handler,
IRQF_TRIGGER_HIGH,
"TPM SERIRQ management", chip);
if (err < 0) {
dev_err(chip->dev , "TPM SERIRQ signals %d not available\n",
gpio_to_irq(platform_data->io_serirq));
goto _irq_set;
}
err = I2C_READ_DATA(client, TPM_INT_ENABLE, &intmask, 1);
if (err < 0)
goto _irq_set;
intmask |= TPM_INTF_CMD_READY_INT
| TPM_INTF_FIFO_AVALAIBLE_INT
| TPM_INTF_WAKE_UP_READY_INT
| TPM_INTF_LOCALITY_CHANGE_INT
| TPM_INTF_STS_VALID_INT
| TPM_INTF_DATA_AVAIL_INT;
err = I2C_WRITE_DATA(client, TPM_INT_ENABLE, &intmask, 1);
if (err < 0)
goto _irq_set;
intmask = TPM_GLOBAL_INT_ENABLE;
err = I2C_WRITE_DATA(client, (TPM_INT_ENABLE + 3), &intmask, 1);
if (err < 0)
goto _irq_set;
err = I2C_READ_DATA(client, TPM_INT_STATUS, &intmask, 1);
if (err < 0)
goto _irq_set;
chip->vendor.irq = interrupts;
tpm_gen_interrupt(chip);
}
tpm_get_timeouts(chip);
i2c_set_clientdata(client, chip);
dev_info(chip->dev, "TPM I2C Initialized\n");
return 0;
_irq_set:
free_irq(gpio_to_irq(platform_data->io_serirq), (void *)chip);
_gpio_init2:
if (interrupts)
gpio_free(platform_data->io_serirq);
_gpio_init1:
if (power_mgt)
gpio_free(platform_data->io_lpcpd);
_tpm_clean_response2:
kzfree(platform_data->tpm_i2c_buffer[1]);
platform_data->tpm_i2c_buffer[1] = NULL;
_tpm_clean_response1:
kzfree(platform_data->tpm_i2c_buffer[0]);
platform_data->tpm_i2c_buffer[0] = NULL;
_tpm_clean_answer:
tpm_remove_hardware(chip->dev);
end:
pr_info("TPM I2C initialisation fail\n");
return err;
}
/*
* tpm_st33_i2c_remove remove the TPM device
* @param: client, the i2c_client drescription (TPM I2C description).
clear_bit(0, &chip->is_open);
* @return: 0 in case of success.
*/
static int tpm_st33_i2c_remove(struct i2c_client *client)
{
struct tpm_chip *chip = (struct tpm_chip *)i2c_get_clientdata(client);
struct st33zp24_platform_data *pin_infos =
((struct i2c_client *)TPM_VPRIV(chip))->dev.platform_data;
if (pin_infos != NULL) {
free_irq(pin_infos->io_serirq, chip);
gpio_free(pin_infos->io_serirq);
gpio_free(pin_infos->io_lpcpd);
tpm_remove_hardware(chip->dev);
if (pin_infos->tpm_i2c_buffer[1] != NULL) {
kzfree(pin_infos->tpm_i2c_buffer[1]);
pin_infos->tpm_i2c_buffer[1] = NULL;
}
if (pin_infos->tpm_i2c_buffer[0] != NULL) {
kzfree(pin_infos->tpm_i2c_buffer[0]);
pin_infos->tpm_i2c_buffer[0] = NULL;
}
}
return 0;
}
#ifdef CONFIG_PM_SLEEP
/*
* tpm_st33_i2c_pm_suspend suspend the TPM device
* Added: Work around when suspend and no tpm application is running, suspend
* may fail because chip->data_buffer is not set (only set in tpm_open in Linux
* TPM core)
* @param: client, the i2c_client drescription (TPM I2C description).
* @param: mesg, the power management message.
* @return: 0 in case of success.
*/
static int tpm_st33_i2c_pm_suspend(struct device *dev)
{
struct tpm_chip *chip = dev_get_drvdata(dev);
struct st33zp24_platform_data *pin_infos = dev->platform_data;
int ret = 0;
if (power_mgt) {
gpio_set_value(pin_infos->io_lpcpd, 0);
} else {
if (chip->data_buffer == NULL)
chip->data_buffer = pin_infos->tpm_i2c_buffer[0];
ret = tpm_pm_suspend(dev);
}
return ret;
} /* tpm_st33_i2c_suspend() */
/*
* tpm_st33_i2c_pm_resume resume the TPM device
* @param: client, the i2c_client drescription (TPM I2C description).
* @return: 0 in case of success.
*/
static int tpm_st33_i2c_pm_resume(struct device *dev)
{
struct tpm_chip *chip = dev_get_drvdata(dev);
struct st33zp24_platform_data *pin_infos = dev->platform_data;
int ret = 0;
if (power_mgt) {
gpio_set_value(pin_infos->io_lpcpd, 1);
ret = wait_for_serirq_timeout(chip,
(chip->vendor.status(chip) &
TPM_STS_VALID) == TPM_STS_VALID,
chip->vendor.timeout_b);
} else {
if (chip->data_buffer == NULL)
chip->data_buffer = pin_infos->tpm_i2c_buffer[0];
ret = tpm_pm_resume(dev);
if (!ret)
tpm_do_selftest(chip);
}
return ret;
} /* tpm_st33_i2c_pm_resume() */
#endif
static const struct i2c_device_id tpm_st33_i2c_id[] = {
{TPM_ST33_I2C, 0},
{}
};
MODULE_DEVICE_TABLE(i2c, tpm_st33_i2c_id);
static SIMPLE_DEV_PM_OPS(tpm_st33_i2c_ops, tpm_st33_i2c_pm_suspend,
tpm_st33_i2c_pm_resume);
static struct i2c_driver tpm_st33_i2c_driver = {
.driver = {
.owner = THIS_MODULE,
.name = TPM_ST33_I2C,
.pm = &tpm_st33_i2c_ops,
},
.probe = tpm_st33_i2c_probe,
.remove = tpm_st33_i2c_remove,
.id_table = tpm_st33_i2c_id
};
module_i2c_driver(tpm_st33_i2c_driver);
MODULE_AUTHOR("Christophe Ricard (tpmsupport@st.com)");
MODULE_DESCRIPTION("STM TPM I2C ST33 Driver");
MODULE_VERSION("1.2.0");
MODULE_LICENSE("GPL");