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tpm: st33zp24: switch to using gpiod API
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Switch the driver from legacy gpio API (that uses flat GPIO numbering)
to the newer gpiod API (which used descriptors and respects line
polarities specified in ACPI or device tree).

Because gpio handling code for SPI and I2C variants duplicates each
other it is moved into the core code for the driver.

Also, it seems that the driver never assigned tpm_dev->io_lpcpd in the
past, so gpio-based power management was most likely not working ever.

Signed-off-by: Dmitry Torokhov <[email protected]>
Reviewed-by: Jarkko Sakkinen <[email protected]>
Signed-off-by: Jarkko Sakkinen <[email protected]>
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@dtor @jarkkojs
dtor authored and jarkkojs committed Dec 8, 2022
1 parent 0459302 commit 3f80190
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Showing 4 changed files with 39 additions and 205 deletions.
101 changes: 2 additions & 99 deletions drivers/char/tpm/st33zp24/i2c.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -6,10 +6,7 @@

#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/of.h>
#include <linux/acpi.h>
#include <linux/tpm.h>

Expand All @@ -21,7 +18,6 @@
struct st33zp24_i2c_phy {
struct i2c_client *client;
u8 buf[ST33ZP24_BUFSIZE + 1];
int io_lpcpd;
};

/*
Expand Down Expand Up @@ -98,85 +94,6 @@ static const struct st33zp24_phy_ops i2c_phy_ops = {
.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;
}

/*
* st33zp24_i2c_probe initialize the TPM device
* @param: client, the i2c_client description (TPM I2C description).
Expand All @@ -187,7 +104,6 @@ static int st33zp24_i2c_of_request_resources(struct i2c_client *client)
static int st33zp24_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int ret;
struct st33zp24_i2c_phy *phy;

if (!client) {
Expand All @@ -208,20 +124,7 @@ static int st33zp24_i2c_probe(struct i2c_client *client,

phy->client = client;

if (client->dev.of_node) {
ret = st33zp24_i2c_of_request_resources(client);
if (ret)
return ret;
} else if (ACPI_HANDLE(&client->dev)) {
ret = st33zp24_i2c_acpi_request_resources(client);
if (ret)
return ret;
} else {
return -ENODEV;
}

return st33zp24_probe(phy, &i2c_phy_ops, &client->dev, client->irq,
phy->io_lpcpd);
return st33zp24_probe(phy, &i2c_phy_ops, &client->dev, client->irq);
}

/*
Expand Down
100 changes: 2 additions & 98 deletions drivers/char/tpm/st33zp24/spi.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -6,10 +6,7 @@

#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/of.h>
#include <linux/acpi.h>
#include <linux/tpm.h>

Expand Down Expand Up @@ -60,7 +57,6 @@ struct st33zp24_spi_phy {
u8 tx_buf[ST33ZP24_SPI_BUFFER_SIZE];
u8 rx_buf[ST33ZP24_SPI_BUFFER_SIZE];

int io_lpcpd;
int latency;
};

Expand Down Expand Up @@ -217,84 +213,6 @@ static const struct st33zp24_phy_ops spi_phy_ops = {
.recv = st33zp24_spi_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_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;
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(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;
int gpio;
int ret;

pp = spi_dev->dev.of_node;
if (!pp) {
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(&spi_dev->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(&spi_dev->dev, gpio,
GPIOF_OUT_INIT_HIGH, "TPM IO LPCPD");
if (ret) {
dev_err(&spi_dev->dev, "Failed to request lpcpd pin\n");
return -ENODEV;
}
phy->io_lpcpd = gpio;

return 0;
}

/*
* st33zp24_spi_probe initialize the TPM device
* @param: dev, the spi_device description (TPM SPI description).
Expand All @@ -303,7 +221,6 @@ static int st33zp24_spi_of_request_resources(struct spi_device *spi_dev)
*/
static int st33zp24_spi_probe(struct spi_device *dev)
{
int ret;
struct st33zp24_spi_phy *phy;

/* Check SPI platform functionnalities */
Expand All @@ -320,24 +237,11 @@ static int st33zp24_spi_probe(struct spi_device *dev)

phy->spi_device = dev;

if (dev->dev.of_node) {
ret = st33zp24_spi_of_request_resources(dev);
if (ret)
return ret;
} else if (ACPI_HANDLE(&dev->dev)) {
ret = st33zp24_spi_acpi_request_resources(dev);
if (ret)
return ret;
} else {
return -ENODEV;
}

phy->latency = st33zp24_spi_evaluate_latency(phy);
if (phy->latency <= 0)
return -ENODEV;

return st33zp24_probe(phy, &spi_phy_ops, &dev->dev, dev->irq,
phy->io_lpcpd);
return st33zp24_probe(phy, &spi_phy_ops, &dev->dev, dev->irq);
}

/*
Expand Down
39 changes: 33 additions & 6 deletions drivers/char/tpm/st33zp24/st33zp24.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -4,6 +4,7 @@
* Copyright (C) 2009 - 2016 STMicroelectronics
*/

#include <linux/acpi.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/kernel.h>
Expand All @@ -12,7 +13,7 @@
#include <linux/freezer.h>
#include <linux/string.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include <linux/io.h>
Expand Down Expand Up @@ -432,11 +433,18 @@ static const struct tpm_class_ops st33zp24_tpm = {
.req_canceled = st33zp24_req_canceled,
};

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 },
{ },
};

/*
* initialize the TPM device
*/
int st33zp24_probe(void *phy_id, const struct st33zp24_phy_ops *ops,
struct device *dev, int irq, int io_lpcpd)
struct device *dev, int irq)
{
int ret;
u8 intmask = 0;
Expand All @@ -463,6 +471,25 @@ int st33zp24_probe(void *phy_id, const struct st33zp24_phy_ops *ops,

tpm_dev->locality = LOCALITY0;

if (ACPI_COMPANION(dev)) {
ret = devm_acpi_dev_add_driver_gpios(dev, acpi_st33zp24_gpios);
if (ret)
return ret;
}

/*
* Get LPCPD GPIO. If lpcpd pin is not specified. This is not an
* issue as power management can be also managed by TPM specific
* commands.
*/
tpm_dev->io_lpcpd = devm_gpiod_get_optional(dev, "lpcpd",
GPIOD_OUT_HIGH);
ret = PTR_ERR_OR_ZERO(tpm_dev->io_lpcpd);
if (ret) {
dev_err(dev, "failed to request lpcpd gpio: %d\n", ret);
return ret;
}

if (irq) {
/* INTERRUPT Setup */
init_waitqueue_head(&tpm_dev->read_queue);
Expand Down Expand Up @@ -525,8 +552,8 @@ int st33zp24_pm_suspend(struct device *dev)

int ret = 0;

if (gpio_is_valid(tpm_dev->io_lpcpd))
gpio_set_value(tpm_dev->io_lpcpd, 0);
if (tpm_dev->io_lpcpd)
gpiod_set_value_cansleep(tpm_dev->io_lpcpd, 0);
else
ret = tpm_pm_suspend(dev);

Expand All @@ -540,8 +567,8 @@ int st33zp24_pm_resume(struct device *dev)
struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
int ret = 0;

if (gpio_is_valid(tpm_dev->io_lpcpd)) {
gpio_set_value(tpm_dev->io_lpcpd, 1);
if (tpm_dev->io_lpcpd) {
gpiod_set_value_cansleep(tpm_dev->io_lpcpd, 1);
ret = wait_for_stat(chip,
TPM_STS_VALID, chip->timeout_b,
&tpm_dev->read_queue, false);
Expand Down
4 changes: 2 additions & 2 deletions drivers/char/tpm/st33zp24/st33zp24.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -20,7 +20,7 @@ struct st33zp24_dev {
int locality;
int irq;
u32 intrs;
int io_lpcpd;
struct gpio_desc *io_lpcpd;
wait_queue_head_t read_queue;
};

Expand All @@ -36,6 +36,6 @@ int st33zp24_pm_resume(struct device *dev);
#endif

int st33zp24_probe(void *phy_id, const struct st33zp24_phy_ops *ops,
struct device *dev, int irq, int io_lpcpd);
struct device *dev, int irq);
void st33zp24_remove(struct tpm_chip *chip);
#endif /* __LOCAL_ST33ZP24_H__ */

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