313 lines
8.4 KiB
C
313 lines
8.4 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* STMicroelectronics TPM I2C Linux driver for TPM ST33ZP24
|
|
* Copyright (C) 2009 - 2016 STMicroelectronics
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/gpio.h>
|
|
#include <linux/gpio/consumer.h>
|
|
#include <linux/of_irq.h>
|
|
#include <linux/of_gpio.h>
|
|
#include <linux/acpi.h>
|
|
#include <linux/tpm.h>
|
|
#include <linux/platform_data/st33zp24.h>
|
|
|
|
#include "../tpm.h"
|
|
#include "st33zp24.h"
|
|
|
|
#define TPM_DUMMY_BYTE 0xAA
|
|
|
|
struct st33zp24_i2c_phy {
|
|
struct i2c_client *client;
|
|
u8 buf[ST33ZP24_BUFSIZE + 1];
|
|
int io_lpcpd;
|
|
};
|
|
|
|
/*
|
|
* 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(void *phy_id, u8 tpm_register, u8 *tpm_data, int tpm_size)
|
|
{
|
|
struct st33zp24_i2c_phy *phy = phy_id;
|
|
|
|
phy->buf[0] = tpm_register;
|
|
memcpy(phy->buf + 1, tpm_data, tpm_size);
|
|
return i2c_master_send(phy->client, phy->buf, 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(void *phy_id, u8 tpm_register, u8 *tpm_data, int tpm_size)
|
|
{
|
|
struct st33zp24_i2c_phy *phy = phy_id;
|
|
u8 status = 0;
|
|
u8 data;
|
|
|
|
data = TPM_DUMMY_BYTE;
|
|
status = write8_reg(phy, tpm_register, &data, 1);
|
|
if (status == 2)
|
|
status = i2c_master_recv(phy->client, tpm_data, tpm_size);
|
|
return status;
|
|
} /* read8_reg() */
|
|
|
|
/*
|
|
* st33zp24_i2c_send
|
|
* Send byte to the TIS register according to the ST33ZP24 I2C protocol.
|
|
* @param: phy_id, the phy 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.
|
|
*/
|
|
static int st33zp24_i2c_send(void *phy_id, u8 tpm_register, u8 *tpm_data,
|
|
int tpm_size)
|
|
{
|
|
return write8_reg(phy_id, tpm_register | TPM_WRITE_DIRECTION, tpm_data,
|
|
tpm_size);
|
|
}
|
|
|
|
/*
|
|
* st33zp24_i2c_recv
|
|
* Recv byte from the TIS register according to the ST33ZP24 I2C protocol.
|
|
* @param: phy_id, the phy 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.
|
|
*/
|
|
static int st33zp24_i2c_recv(void *phy_id, u8 tpm_register, u8 *tpm_data,
|
|
int tpm_size)
|
|
{
|
|
return read8_reg(phy_id, tpm_register, tpm_data, tpm_size);
|
|
}
|
|
|
|
static const struct st33zp24_phy_ops i2c_phy_ops = {
|
|
.send = st33zp24_i2c_send,
|
|
.recv = st33zp24_i2c_recv,
|
|
};
|
|
|
|
static const struct acpi_gpio_params lpcpd_gpios = { 1, 0, false };
|
|
|
|
static const struct acpi_gpio_mapping acpi_st33zp24_gpios[] = {
|
|
{ "lpcpd-gpios", &lpcpd_gpios, 1 },
|
|
{},
|
|
};
|
|
|
|
static int st33zp24_i2c_acpi_request_resources(struct i2c_client *client)
|
|
{
|
|
struct tpm_chip *chip = i2c_get_clientdata(client);
|
|
struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
|
|
struct st33zp24_i2c_phy *phy = tpm_dev->phy_id;
|
|
struct gpio_desc *gpiod_lpcpd;
|
|
struct device *dev = &client->dev;
|
|
int ret;
|
|
|
|
ret = devm_acpi_dev_add_driver_gpios(dev, acpi_st33zp24_gpios);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* Get LPCPD GPIO from ACPI */
|
|
gpiod_lpcpd = devm_gpiod_get(dev, "lpcpd", GPIOD_OUT_HIGH);
|
|
if (IS_ERR(gpiod_lpcpd)) {
|
|
dev_err(&client->dev,
|
|
"Failed to retrieve lpcpd-gpios from acpi.\n");
|
|
phy->io_lpcpd = -1;
|
|
/*
|
|
* lpcpd pin is not specified. This is not an issue as
|
|
* power management can be also managed by TPM specific
|
|
* commands. So leave with a success status code.
|
|
*/
|
|
return 0;
|
|
}
|
|
|
|
phy->io_lpcpd = desc_to_gpio(gpiod_lpcpd);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int st33zp24_i2c_of_request_resources(struct i2c_client *client)
|
|
{
|
|
struct tpm_chip *chip = i2c_get_clientdata(client);
|
|
struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
|
|
struct st33zp24_i2c_phy *phy = tpm_dev->phy_id;
|
|
struct device_node *pp;
|
|
int gpio;
|
|
int ret;
|
|
|
|
pp = client->dev.of_node;
|
|
if (!pp) {
|
|
dev_err(&client->dev, "No platform data\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
/* Get GPIO from device tree */
|
|
gpio = of_get_named_gpio(pp, "lpcpd-gpios", 0);
|
|
if (gpio < 0) {
|
|
dev_err(&client->dev,
|
|
"Failed to retrieve lpcpd-gpios from dts.\n");
|
|
phy->io_lpcpd = -1;
|
|
/*
|
|
* lpcpd pin is not specified. This is not an issue as
|
|
* power management can be also managed by TPM specific
|
|
* commands. So leave with a success status code.
|
|
*/
|
|
return 0;
|
|
}
|
|
/* GPIO request and configuration */
|
|
ret = devm_gpio_request_one(&client->dev, gpio,
|
|
GPIOF_OUT_INIT_HIGH, "TPM IO LPCPD");
|
|
if (ret) {
|
|
dev_err(&client->dev, "Failed to request lpcpd pin\n");
|
|
return -ENODEV;
|
|
}
|
|
phy->io_lpcpd = gpio;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int st33zp24_i2c_request_resources(struct i2c_client *client)
|
|
{
|
|
struct tpm_chip *chip = i2c_get_clientdata(client);
|
|
struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
|
|
struct st33zp24_i2c_phy *phy = tpm_dev->phy_id;
|
|
struct st33zp24_platform_data *pdata;
|
|
int ret;
|
|
|
|
pdata = client->dev.platform_data;
|
|
if (!pdata) {
|
|
dev_err(&client->dev, "No platform data\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
/* store for late use */
|
|
phy->io_lpcpd = pdata->io_lpcpd;
|
|
|
|
if (gpio_is_valid(pdata->io_lpcpd)) {
|
|
ret = devm_gpio_request_one(&client->dev,
|
|
pdata->io_lpcpd, GPIOF_OUT_INIT_HIGH,
|
|
"TPM IO_LPCPD");
|
|
if (ret) {
|
|
dev_err(&client->dev, "Failed to request lpcpd pin\n");
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* st33zp24_i2c_probe initialize the TPM device
|
|
* @param: client, the i2c_client description (TPM I2C description).
|
|
* @param: id, the i2c_device_id struct.
|
|
* @return: 0 in case of success.
|
|
* -1 in other case.
|
|
*/
|
|
static int st33zp24_i2c_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
int ret;
|
|
struct st33zp24_platform_data *pdata;
|
|
struct st33zp24_i2c_phy *phy;
|
|
|
|
if (!client) {
|
|
pr_info("%s: i2c client is NULL. Device not accessible.\n",
|
|
__func__);
|
|
return -ENODEV;
|
|
}
|
|
|
|
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
|
|
dev_info(&client->dev, "client not i2c capable\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
phy = devm_kzalloc(&client->dev, sizeof(struct st33zp24_i2c_phy),
|
|
GFP_KERNEL);
|
|
if (!phy)
|
|
return -ENOMEM;
|
|
|
|
phy->client = client;
|
|
|
|
pdata = client->dev.platform_data;
|
|
if (!pdata && client->dev.of_node) {
|
|
ret = st33zp24_i2c_of_request_resources(client);
|
|
if (ret)
|
|
return ret;
|
|
} else if (pdata) {
|
|
ret = st33zp24_i2c_request_resources(client);
|
|
if (ret)
|
|
return ret;
|
|
} else if (ACPI_HANDLE(&client->dev)) {
|
|
ret = st33zp24_i2c_acpi_request_resources(client);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
return st33zp24_probe(phy, &i2c_phy_ops, &client->dev, client->irq,
|
|
phy->io_lpcpd);
|
|
}
|
|
|
|
/*
|
|
* st33zp24_i2c_remove remove the TPM device
|
|
* @param: client, the i2c_client description (TPM I2C description).
|
|
* @return: 0 in case of success.
|
|
*/
|
|
static void st33zp24_i2c_remove(struct i2c_client *client)
|
|
{
|
|
struct tpm_chip *chip = i2c_get_clientdata(client);
|
|
|
|
st33zp24_remove(chip);
|
|
}
|
|
|
|
static const struct i2c_device_id st33zp24_i2c_id[] = {
|
|
{TPM_ST33_I2C, 0},
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, st33zp24_i2c_id);
|
|
|
|
static const struct of_device_id of_st33zp24_i2c_match[] = {
|
|
{ .compatible = "st,st33zp24-i2c", },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(of, of_st33zp24_i2c_match);
|
|
|
|
static const struct acpi_device_id st33zp24_i2c_acpi_match[] = {
|
|
{"SMO3324"},
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(acpi, st33zp24_i2c_acpi_match);
|
|
|
|
static SIMPLE_DEV_PM_OPS(st33zp24_i2c_ops, st33zp24_pm_suspend,
|
|
st33zp24_pm_resume);
|
|
|
|
static struct i2c_driver st33zp24_i2c_driver = {
|
|
.driver = {
|
|
.name = TPM_ST33_I2C,
|
|
.pm = &st33zp24_i2c_ops,
|
|
.of_match_table = of_match_ptr(of_st33zp24_i2c_match),
|
|
.acpi_match_table = ACPI_PTR(st33zp24_i2c_acpi_match),
|
|
},
|
|
.probe = st33zp24_i2c_probe,
|
|
.remove = st33zp24_i2c_remove,
|
|
.id_table = st33zp24_i2c_id
|
|
};
|
|
|
|
module_i2c_driver(st33zp24_i2c_driver);
|
|
|
|
MODULE_AUTHOR("TPM support (TPMsupport@list.st.com)");
|
|
MODULE_DESCRIPTION("STM TPM 1.2 I2C ST33 Driver");
|
|
MODULE_VERSION("1.3.0");
|
|
MODULE_LICENSE("GPL");
|