1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * STMicroelectronics TPM I2C Linux driver for TPM ST33ZP24
4  * Copyright (C) 2009 - 2016 STMicroelectronics
8 #include <linux/i2c.h>
30  * Send byte to the TIS register according to the ST33ZP24 I2C protocol.
38 	struct st33zp24_i2c_phy *phy = phy_id;  in write8_reg()  local
40 	phy->buf[0] = tpm_register;  in write8_reg()
41 	memcpy(phy->buf + 1, tpm_data, tpm_size);  in write8_reg()
42 	return i2c_master_send(phy->client, phy->buf, tpm_size + 1);  in write8_reg()
47  * Recv byte from the TIS register according to the ST33ZP24 I2C protocol.
55 	struct st33zp24_i2c_phy *phy = phy_id;  in read8_reg()  local
60 	status = write8_reg(phy, tpm_register, &data, 1);  in read8_reg()
62 		status = i2c_master_recv(phy->client, tpm_data, tpm_size);  in read8_reg()
68  * Send byte to the TIS register according to the ST33ZP24 I2C protocol.
69  * @param: phy_id, the phy description
84  * Recv byte from the TIS register according to the ST33ZP24 I2C protocol.
85  * @param: phy_id, the phy description
105 	{ "lpcpd-gpios", &lpcpd_gpios, 1 },
112 	struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);  in st33zp24_i2c_acpi_request_resources()
113 	struct st33zp24_i2c_phy *phy = tpm_dev->phy_id;  in st33zp24_i2c_acpi_request_resources()  local
115 	struct device *dev = &client->dev;  in st33zp24_i2c_acpi_request_resources()
125 		dev_err(&client->dev,  in st33zp24_i2c_acpi_request_resources()
126 			"Failed to retrieve lpcpd-gpios from acpi.\n");  in st33zp24_i2c_acpi_request_resources()
127 		phy->io_lpcpd = -1;  in st33zp24_i2c_acpi_request_resources()
136 	phy->io_lpcpd = desc_to_gpio(gpiod_lpcpd);  in st33zp24_i2c_acpi_request_resources()
144 	struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);  in st33zp24_i2c_of_request_resources()
145 	struct st33zp24_i2c_phy *phy = tpm_dev->phy_id;  in st33zp24_i2c_of_request_resources()  local
150 	pp = client->dev.of_node;  in st33zp24_i2c_of_request_resources()
152 		dev_err(&client->dev, "No platform data\n");  in st33zp24_i2c_of_request_resources()
153 		return -ENODEV;  in st33zp24_i2c_of_request_resources()
157 	gpio = of_get_named_gpio(pp, "lpcpd-gpios", 0);  in st33zp24_i2c_of_request_resources()
159 		dev_err(&client->dev,  in st33zp24_i2c_of_request_resources()
160 			"Failed to retrieve lpcpd-gpios from dts.\n");  in st33zp24_i2c_of_request_resources()
161 		phy->io_lpcpd = -1;  in st33zp24_i2c_of_request_resources()
170 	ret = devm_gpio_request_one(&client->dev, gpio,  in st33zp24_i2c_of_request_resources()
173 		dev_err(&client->dev, "Failed to request lpcpd pin\n");  in st33zp24_i2c_of_request_resources()
174 		return -ENODEV;  in st33zp24_i2c_of_request_resources()
176 	phy->io_lpcpd = gpio;  in st33zp24_i2c_of_request_resources()
184 	struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);  in st33zp24_i2c_request_resources()
185 	struct st33zp24_i2c_phy *phy = tpm_dev->phy_id;  in st33zp24_i2c_request_resources()  local
189 	pdata = client->dev.platform_data;  in st33zp24_i2c_request_resources()
191 		dev_err(&client->dev, "No platform data\n");  in st33zp24_i2c_request_resources()
192 		return -ENODEV;  in st33zp24_i2c_request_resources()
196 	phy->io_lpcpd = pdata->io_lpcpd;  in st33zp24_i2c_request_resources()
198 	if (gpio_is_valid(pdata->io_lpcpd)) {  in st33zp24_i2c_request_resources()
199 		ret = devm_gpio_request_one(&client->dev,  in st33zp24_i2c_request_resources()
200 				pdata->io_lpcpd, GPIOF_OUT_INIT_HIGH,  in st33zp24_i2c_request_resources()
203 			dev_err(&client->dev, "Failed to request lpcpd pin\n");  in st33zp24_i2c_request_resources()
213  * @param: client, the i2c_client description (TPM I2C description).
216  *	 -1 in other case.
223 	struct st33zp24_i2c_phy *phy;  in st33zp24_i2c_probe()  local
226 		pr_info("%s: i2c client is NULL. Device not accessible.\n",  in st33zp24_i2c_probe()
228 		return -ENODEV;  in st33zp24_i2c_probe()
231 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {  in st33zp24_i2c_probe()
232 		dev_info(&client->dev, "client not i2c capable\n");  in st33zp24_i2c_probe()
233 		return -ENODEV;  in st33zp24_i2c_probe()
236 	phy = devm_kzalloc(&client->dev, sizeof(struct st33zp24_i2c_phy),  in st33zp24_i2c_probe()
238 	if (!phy)  in st33zp24_i2c_probe()
239 		return -ENOMEM;  in st33zp24_i2c_probe()
241 	phy->client = client;  in st33zp24_i2c_probe()
243 	pdata = client->dev.platform_data;  in st33zp24_i2c_probe()
244 	if (!pdata && client->dev.of_node) {  in st33zp24_i2c_probe()
252 	} else if (ACPI_HANDLE(&client->dev)) {  in st33zp24_i2c_probe()
258 	return st33zp24_probe(phy, &i2c_phy_ops, &client->dev, client->irq,  in st33zp24_i2c_probe()
259 			      phy->io_lpcpd);  in st33zp24_i2c_probe()
264  * @param: client, the i2c_client description (TPM I2C description).
283 MODULE_DEVICE_TABLE(i2c, st33zp24_i2c_id);
286 	{ .compatible = "st,st33zp24-i2c", },
315 MODULE_DESCRIPTION("STM TPM 1.2 I2C ST33 Driver");