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path: root/drivers/char/tpm/st33zp24/spi.c
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Diffstat (limited to 'drivers/char/tpm/st33zp24/spi.c')
-rw-r--r--drivers/char/tpm/st33zp24/spi.c184
1 files changed, 108 insertions, 76 deletions
diff --git a/drivers/char/tpm/st33zp24/spi.c b/drivers/char/tpm/st33zp24/spi.c
index f974c945c97a..9f5a0117098c 100644
--- a/drivers/char/tpm/st33zp24/spi.c
+++ b/drivers/char/tpm/st33zp24/spi.c
@@ -1,6 +1,6 @@
/*
* STMicroelectronics TPM SPI Linux driver for TPM ST33ZP24
- * Copyright (C) 2009 - 2015 STMicroelectronics
+ * Copyright (C) 2009 - 2016 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
@@ -19,11 +19,14 @@
#include <linux/module.h>
#include <linux/spi/spi.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_DATA_FIFO 0x24
@@ -66,7 +69,7 @@
struct st33zp24_spi_phy {
struct spi_device *spi_device;
- struct spi_transfer spi_xfer;
+
u8 tx_buf[ST33ZP24_SPI_BUFFER_SIZE];
u8 rx_buf[ST33ZP24_SPI_BUFFER_SIZE];
@@ -110,43 +113,39 @@ static int st33zp24_status_to_errno(u8 code)
static int st33zp24_spi_send(void *phy_id, u8 tpm_register, u8 *tpm_data,
int tpm_size)
{
- u8 data = 0;
- int total_length = 0, nbr_dummy_bytes = 0, ret = 0;
+ int total_length = 0, ret = 0;
struct st33zp24_spi_phy *phy = phy_id;
struct spi_device *dev = phy->spi_device;
- u8 *tx_buf = (u8 *)phy->spi_xfer.tx_buf;
- u8 *rx_buf = phy->spi_xfer.rx_buf;
+ struct spi_transfer spi_xfer = {
+ .tx_buf = phy->tx_buf,
+ .rx_buf = phy->rx_buf,
+ };
/* Pre-Header */
- data = TPM_WRITE_DIRECTION | LOCALITY0;
- memcpy(tx_buf + total_length, &data, sizeof(data));
- total_length++;
- data = tpm_register;
- memcpy(tx_buf + total_length, &data, sizeof(data));
- total_length++;
+ phy->tx_buf[total_length++] = TPM_WRITE_DIRECTION | LOCALITY0;
+ phy->tx_buf[total_length++] = tpm_register;
if (tpm_size > 0 && tpm_register == TPM_DATA_FIFO) {
- tx_buf[total_length++] = tpm_size >> 8;
- tx_buf[total_length++] = tpm_size;
+ phy->tx_buf[total_length++] = tpm_size >> 8;
+ phy->tx_buf[total_length++] = tpm_size;
}
- memcpy(&tx_buf[total_length], tpm_data, tpm_size);
+ memcpy(&phy->tx_buf[total_length], tpm_data, tpm_size);
total_length += tpm_size;
- nbr_dummy_bytes = phy->latency;
- memset(&tx_buf[total_length], TPM_DUMMY_BYTE, nbr_dummy_bytes);
+ memset(&phy->tx_buf[total_length], TPM_DUMMY_BYTE, phy->latency);
- phy->spi_xfer.len = total_length + nbr_dummy_bytes;
+ spi_xfer.len = total_length + phy->latency;
- ret = spi_sync_transfer(dev, &phy->spi_xfer, 1);
+ ret = spi_sync_transfer(dev, &spi_xfer, 1);
if (ret == 0)
- ret = rx_buf[total_length + nbr_dummy_bytes - 1];
+ ret = phy->rx_buf[total_length + phy->latency - 1];
return st33zp24_status_to_errno(ret);
} /* st33zp24_spi_send() */
/*
- * read8_recv
+ * st33zp24_spi_read8_recv
* Recv byte from the TIS register according to the ST33ZP24 SPI protocol.
* @param: phy_id, the phy description
* @param: tpm_register, the tpm tis register where the data should be read
@@ -154,40 +153,37 @@ static int st33zp24_spi_send(void *phy_id, u8 tpm_register, u8 *tpm_data,
* @param: tpm_size, tpm TPM response size to read.
* @return: should be zero if success else a negative error code.
*/
-static int read8_reg(void *phy_id, u8 tpm_register, u8 *tpm_data, int tpm_size)
+static int st33zp24_spi_read8_reg(void *phy_id, u8 tpm_register, u8 *tpm_data,
+ int tpm_size)
{
- u8 data = 0;
- int total_length = 0, nbr_dummy_bytes, ret;
+ int total_length = 0, ret;
struct st33zp24_spi_phy *phy = phy_id;
struct spi_device *dev = phy->spi_device;
- u8 *tx_buf = (u8 *)phy->spi_xfer.tx_buf;
- u8 *rx_buf = phy->spi_xfer.rx_buf;
+ struct spi_transfer spi_xfer = {
+ .tx_buf = phy->tx_buf,
+ .rx_buf = phy->rx_buf,
+ };
/* Pre-Header */
- data = LOCALITY0;
- memcpy(tx_buf + total_length, &data, sizeof(data));
- total_length++;
- data = tpm_register;
- memcpy(tx_buf + total_length, &data, sizeof(data));
- total_length++;
+ phy->tx_buf[total_length++] = LOCALITY0;
+ phy->tx_buf[total_length++] = tpm_register;
- nbr_dummy_bytes = phy->latency;
- memset(&tx_buf[total_length], TPM_DUMMY_BYTE,
- nbr_dummy_bytes + tpm_size);
+ memset(&phy->tx_buf[total_length], TPM_DUMMY_BYTE,
+ phy->latency + tpm_size);
- phy->spi_xfer.len = total_length + nbr_dummy_bytes + tpm_size;
+ spi_xfer.len = total_length + phy->latency + tpm_size;
/* header + status byte + size of the data + status byte */
- ret = spi_sync_transfer(dev, &phy->spi_xfer, 1);
+ ret = spi_sync_transfer(dev, &spi_xfer, 1);
if (tpm_size > 0 && ret == 0) {
- ret = rx_buf[total_length + nbr_dummy_bytes - 1];
+ ret = phy->rx_buf[total_length + phy->latency - 1];
- memcpy(tpm_data, rx_buf + total_length + nbr_dummy_bytes,
+ memcpy(tpm_data, phy->rx_buf + total_length + phy->latency,
tpm_size);
}
return ret;
-} /* read8_reg() */
+} /* st33zp24_spi_read8_reg() */
/*
* st33zp24_spi_recv
@@ -203,13 +199,13 @@ static int st33zp24_spi_recv(void *phy_id, u8 tpm_register, u8 *tpm_data,
{
int ret;
- ret = read8_reg(phy_id, tpm_register, tpm_data, tpm_size);
+ ret = st33zp24_spi_read8_reg(phy_id, tpm_register, tpm_data, tpm_size);
if (!st33zp24_status_to_errno(ret))
return tpm_size;
return ret;
} /* st33zp24_spi_recv() */
-static int evaluate_latency(void *phy_id)
+static int st33zp24_spi_evaluate_latency(void *phy_id)
{
struct st33zp24_spi_phy *phy = phy_id;
int latency = 1, status = 0;
@@ -217,9 +213,15 @@ static int evaluate_latency(void *phy_id)
while (!status && latency < MAX_SPI_LATENCY) {
phy->latency = latency;
- status = read8_reg(phy_id, TPM_INTF_CAPABILITY, &data, 1);
+ status = st33zp24_spi_read8_reg(phy_id, TPM_INTF_CAPABILITY,
+ &data, 1);
latency++;
}
+ if (status < 0)
+ return status;
+ if (latency == MAX_SPI_LATENCY)
+ return -ENODEV;
+
return latency - 1;
} /* evaluate_latency() */
@@ -228,24 +230,52 @@ static const struct st33zp24_phy_ops spi_phy_ops = {
.recv = st33zp24_spi_recv,
};
-#ifdef CONFIG_OF
-static int tpm_stm_spi_of_request_resources(struct st33zp24_spi_phy *phy)
+static int st33zp24_spi_acpi_request_resources(struct spi_device *spi_dev)
{
+ struct tpm_chip *chip = spi_get_drvdata(spi_dev);
+ struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
+ struct st33zp24_spi_phy *phy = tpm_dev->phy_id;
+ struct gpio_desc *gpiod_lpcpd;
+ struct device *dev = &spi_dev->dev;
+
+ /* Get LPCPD GPIO from ACPI */
+ gpiod_lpcpd = devm_gpiod_get_index(dev, "TPM IO LPCPD", 1,
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(gpiod_lpcpd)) {
+ dev_err(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_spi_of_request_resources(struct spi_device *spi_dev)
+{
+ struct tpm_chip *chip = spi_get_drvdata(spi_dev);
+ struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
+ struct st33zp24_spi_phy *phy = tpm_dev->phy_id;
struct device_node *pp;
- struct spi_device *dev = phy->spi_device;
int gpio;
int ret;
- pp = dev->dev.of_node;
+ pp = spi_dev->dev.of_node;
if (!pp) {
- dev_err(&dev->dev, "No platform data\n");
+ dev_err(&spi_dev->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(&dev->dev,
+ dev_err(&spi_dev->dev,
"Failed to retrieve lpcpd-gpios from dts.\n");
phy->io_lpcpd = -1;
/*
@@ -256,26 +286,22 @@ static int tpm_stm_spi_of_request_resources(struct st33zp24_spi_phy *phy)
return 0;
}
/* GPIO request and configuration */
- ret = devm_gpio_request_one(&dev->dev, gpio,
+ ret = devm_gpio_request_one(&spi_dev->dev, gpio,
GPIOF_OUT_INIT_HIGH, "TPM IO LPCPD");
if (ret) {
- dev_err(&dev->dev, "Failed to request lpcpd pin\n");
+ dev_err(&spi_dev->dev, "Failed to request lpcpd pin\n");
return -ENODEV;
}
phy->io_lpcpd = gpio;
return 0;
}
-#else
-static int tpm_stm_spi_of_request_resources(struct st33zp24_spi_phy *phy)
-{
- return -ENODEV;
-}
-#endif
-static int tpm_stm_spi_request_resources(struct spi_device *dev,
- struct st33zp24_spi_phy *phy)
+static int st33zp24_spi_request_resources(struct spi_device *dev)
{
+ struct tpm_chip *chip = spi_get_drvdata(dev);
+ struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
+ struct st33zp24_spi_phy *phy = tpm_dev->phy_id;
struct st33zp24_platform_data *pdata;
int ret;
@@ -303,13 +329,12 @@ static int tpm_stm_spi_request_resources(struct spi_device *dev,
}
/*
- * tpm_st33_spi_probe initialize the TPM device
+ * st33zp24_spi_probe initialize the TPM device
* @param: dev, the spi_device drescription (TPM SPI description).
* @return: 0 in case of success.
* or a negative value describing the error.
*/
-static int
-tpm_st33_spi_probe(struct spi_device *dev)
+static int st33zp24_spi_probe(struct spi_device *dev)
{
int ret;
struct st33zp24_platform_data *pdata;
@@ -328,21 +353,23 @@ tpm_st33_spi_probe(struct spi_device *dev)
return -ENOMEM;
phy->spi_device = dev;
+
pdata = dev->dev.platform_data;
if (!pdata && dev->dev.of_node) {
- ret = tpm_stm_spi_of_request_resources(phy);
+ ret = st33zp24_spi_of_request_resources(dev);
if (ret)
return ret;
} else if (pdata) {
- ret = tpm_stm_spi_request_resources(dev, phy);
+ ret = st33zp24_spi_request_resources(dev);
+ if (ret)
+ return ret;
+ } else if (ACPI_HANDLE(&dev->dev)) {
+ ret = st33zp24_spi_acpi_request_resources(dev);
if (ret)
return ret;
}
- phy->spi_xfer.tx_buf = phy->tx_buf;
- phy->spi_xfer.rx_buf = phy->rx_buf;
-
- phy->latency = evaluate_latency(phy);
+ phy->latency = st33zp24_spi_evaluate_latency(phy);
if (phy->latency <= 0)
return -ENODEV;
@@ -351,11 +378,11 @@ tpm_st33_spi_probe(struct spi_device *dev)
}
/*
- * tpm_st33_spi_remove remove the TPM device
+ * st33zp24_spi_remove remove the TPM device
* @param: client, the spi_device drescription (TPM SPI description).
* @return: 0 in case of success.
*/
-static int tpm_st33_spi_remove(struct spi_device *dev)
+static int st33zp24_spi_remove(struct spi_device *dev)
{
struct tpm_chip *chip = spi_get_drvdata(dev);
@@ -368,29 +395,34 @@ static const struct spi_device_id st33zp24_spi_id[] = {
};
MODULE_DEVICE_TABLE(spi, st33zp24_spi_id);
-#ifdef CONFIG_OF
static const struct of_device_id of_st33zp24_spi_match[] = {
{ .compatible = "st,st33zp24-spi", },
{}
};
MODULE_DEVICE_TABLE(of, of_st33zp24_spi_match);
-#endif
+
+static const struct acpi_device_id st33zp24_spi_acpi_match[] = {
+ {"SMO3324"},
+ {}
+};
+MODULE_DEVICE_TABLE(acpi, st33zp24_spi_acpi_match);
static SIMPLE_DEV_PM_OPS(st33zp24_spi_ops, st33zp24_pm_suspend,
st33zp24_pm_resume);
-static struct spi_driver tpm_st33_spi_driver = {
+static struct spi_driver st33zp24_spi_driver = {
.driver = {
.name = TPM_ST33_SPI,
.pm = &st33zp24_spi_ops,
.of_match_table = of_match_ptr(of_st33zp24_spi_match),
+ .acpi_match_table = ACPI_PTR(st33zp24_spi_acpi_match),
},
- .probe = tpm_st33_spi_probe,
- .remove = tpm_st33_spi_remove,
+ .probe = st33zp24_spi_probe,
+ .remove = st33zp24_spi_remove,
.id_table = st33zp24_spi_id,
};
-module_spi_driver(tpm_st33_spi_driver);
+module_spi_driver(st33zp24_spi_driver);
MODULE_AUTHOR("TPM support (TPMsupport@list.st.com)");
MODULE_DESCRIPTION("STM TPM 1.2 SPI ST33 Driver");
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.