drivers/hwmon/pmbus/fsp-3y.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Hardware monitoring driver for FSP 3Y-Power PSUs
  *
  * Copyright (c) 2021 Václav Kubernát, CESNET
  *
  * This driver is mostly reverse engineered with the help of a tool called pmbus_peek written by
  * David Brownell (and later adopted by Jan Kundrát). The device has some sort of a timing issue
  * when switching pages, details are explained in the code. The driver support is limited. It
  * exposes only the values, that have been tested to work correctly. Unsupported values either
  * aren't supported by the devices or their encondings are unknown.
  */

 #include <linux/delay.h>
 #include <linux/i2c.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include "pmbus.h"

 #define YM2151_PAGE_12V_LOG	0x00
 #define YM2151_PAGE_12V_REAL	0x00
 #define YM2151_PAGE_5VSB_LOG	0x01
 #define YM2151_PAGE_5VSB_REAL	0x20
 #define YH5151E_PAGE_12V_LOG	0x00
 #define YH5151E_PAGE_12V_REAL	0x00
 #define YH5151E_PAGE_5V_LOG	0x01
 #define YH5151E_PAGE_5V_REAL	0x10
 #define YH5151E_PAGE_3V3_LOG	0x02
 #define YH5151E_PAGE_3V3_REAL	0x11

 enum chips {
 	ym2151e,
 	yh5151e
 };

 struct fsp3y_data {
 	struct pmbus_driver_info info;
 	int chip;
 	int page;

 	bool vout_linear_11;
 };

 #define to_fsp3y_data(x) container_of(x, struct fsp3y_data, info)

 static int page_log_to_page_real(int page_log, enum chips chip)
 {
 	switch (chip) {
 	case ym2151e:
 		switch (page_log) {
 		case YM2151_PAGE_12V_LOG:
 			return YM2151_PAGE_12V_REAL;
 		case YM2151_PAGE_5VSB_LOG:
 			return YM2151_PAGE_5VSB_REAL;
 		}
 		return -EINVAL;
 	case yh5151e:
 		switch (page_log) {
 		case YH5151E_PAGE_12V_LOG:
 			return YH5151E_PAGE_12V_REAL;
 		case YH5151E_PAGE_5V_LOG:
 			return YH5151E_PAGE_5V_REAL;
 		case YH5151E_PAGE_3V3_LOG:
 			return YH5151E_PAGE_3V3_REAL;
 		}
 		return -EINVAL;
 	}

 	return -EINVAL;
 }

 static int set_page(struct i2c_client *client, int page_log)
 {
 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
 	struct fsp3y_data *data = to_fsp3y_data(info);
 	int rv;
 	int page_real;

 	if (page_log < 0)
 		return 0;

 	page_real = page_log_to_page_real(page_log, data->chip);
 	if (page_real < 0)
 		return page_real;

 	if (data->page != page_real) {
 		rv = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page_real);
 		if (rv < 0)
 			return rv;

 		data->page = page_real;

 		/*
 		 * Testing showed that the device has a timing issue. After
 		 * setting a page, it takes a while, before the device actually
 		 * gives the correct values from the correct page. 20 ms was
 		 * tested to be enough to not give wrong values (15 ms wasn't
 		 * enough).
 		 */
 		usleep_range(20000, 30000);
 	}

 	return 0;
 }

 static int fsp3y_read_byte_data(struct i2c_client *client, int page, int reg)
 {
 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
 	struct fsp3y_data *data = to_fsp3y_data(info);
 	int rv;

 	/*
 	 * Inject an exponent for non-compliant YH5151-E.
 	 */
 	if (data->vout_linear_11 && reg == PMBUS_VOUT_MODE)
 		return 0x1A;

 	rv = set_page(client, page);
 	if (rv < 0)
 		return rv;

 	return i2c_smbus_read_byte_data(client, reg);
 }

 static int fsp3y_read_word_data(struct i2c_client *client, int page, int phase, int reg)
 {
 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
 	struct fsp3y_data *data = to_fsp3y_data(info);
 	int rv;

 	/*
 	 * This masks commands which weren't tested to work correctly. Some of
 	 * the masked commands return 0xFFFF. These would probably get tagged as
 	 * invalid by pmbus_core. Other ones do return values which might be
 	 * useful (that is, they are not 0xFFFF), but their encoding is unknown,
 	 * and so they are unsupported.
 	 */
 	switch (reg) {
 	case PMBUS_READ_FAN_SPEED_1:
 	case PMBUS_READ_IIN:
 	case PMBUS_READ_IOUT:
 	case PMBUS_READ_PIN:
 	case PMBUS_READ_POUT:
 	case PMBUS_READ_TEMPERATURE_1:
 	case PMBUS_READ_TEMPERATURE_2:
 	case PMBUS_READ_TEMPERATURE_3:
 	case PMBUS_READ_VIN:
 	case PMBUS_READ_VOUT:
 	case PMBUS_STATUS_WORD:
 		break;
 	default:
 		return -ENXIO;
 	}

 	rv = set_page(client, page);
 	if (rv < 0)
 		return rv;

 	rv = i2c_smbus_read_word_data(client, reg);
 	if (rv < 0)
 		return rv;

 	/*
 	 * Handle YH-5151E non-compliant linear11 vout voltage.
 	 */
 	if (data->vout_linear_11 && reg == PMBUS_READ_VOUT)
 		rv = sign_extend32(rv, 10) & 0xffff;

 	return rv;
 }

 static struct pmbus_driver_info fsp3y_info[] = {
 	[ym2151e] = {
 		.pages = 2,
 		.func[YM2151_PAGE_12V_LOG] =
 			PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
 			PMBUS_HAVE_PIN | PMBUS_HAVE_POUT  |
 			PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 |
 			PMBUS_HAVE_VIN | PMBUS_HAVE_IIN |
 			PMBUS_HAVE_FAN12,
 		.func[YM2151_PAGE_5VSB_LOG] =
 			PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT,
 		.read_word_data = fsp3y_read_word_data,
 		.read_byte_data = fsp3y_read_byte_data,
 	},
 	[yh5151e] = {
 		.pages = 3,
 		.func[YH5151E_PAGE_12V_LOG] =
 			PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
 			PMBUS_HAVE_POUT  |
 			PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3,
 		.func[YH5151E_PAGE_5V_LOG] =
 			PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
 			PMBUS_HAVE_POUT,
 		.func[YH5151E_PAGE_3V3_LOG] =
 			PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
 			PMBUS_HAVE_POUT,
 		.read_word_data = fsp3y_read_word_data,
 		.read_byte_data = fsp3y_read_byte_data,
 	}
 };

 static int fsp3y_detect(struct i2c_client *client)
 {
 	int rv;
 	u8 buf[I2C_SMBUS_BLOCK_MAX + 1];

 	rv = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
 	if (rv < 0)
 		return rv;

 	buf[rv] = '\0';

 	if (rv == 8) {
 		if (!strcmp(buf, "YM-2151E"))
 			return ym2151e;
 		else if (!strcmp(buf, "YH-5151E"))
 			return yh5151e;
 	}

 	dev_err(&client->dev, "Unsupported model %.*s\n", rv, buf);
 	return -ENODEV;
 }

 static const struct i2c_device_id fsp3y_id[] = {
 	{"ym2151e", ym2151e},
 	{"yh5151e", yh5151e},
 	{ }
 };

 static int fsp3y_probe(struct i2c_client *client)
 {
 	struct fsp3y_data *data;
 	const struct i2c_device_id *id;
 	int rv;

 	data = devm_kzalloc(&client->dev, sizeof(struct fsp3y_data), GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;

 	data->chip = fsp3y_detect(client);
 	if (data->chip < 0)
 		return data->chip;

 	id = i2c_match_id(fsp3y_id, client);
 	if (data->chip != id->driver_data)
 		dev_warn(&client->dev, "Device mismatch: Configured %s (%d), detected %d\n",
 			 id->name, (int)id->driver_data, data->chip);

 	rv = i2c_smbus_read_byte_data(client, PMBUS_PAGE);
 	if (rv < 0)
 		return rv;
 	data->page = rv;

 	data->info = fsp3y_info[data->chip];

 	/*
 	 * YH-5151E sometimes reports vout in linear11 and sometimes in
 	 * linear16. This depends on the exact individual piece of hardware. One
 	 * YH-5151E can use linear16 and another might use linear11 instead.
 	 *
 	 * The format can be recognized by reading VOUT_MODE - if it doesn't
 	 * report a valid exponent, then vout uses linear11. Otherwise, the
 	 * device is compliant and uses linear16.
 	 */
 	data->vout_linear_11 = false;
 	if (data->chip == yh5151e) {
 		rv = i2c_smbus_read_byte_data(client, PMBUS_VOUT_MODE);
 		if (rv < 0)
 			return rv;

 		if (rv == 0xFF)
 			data->vout_linear_11 = true;
 	}

 	return pmbus_do_probe(client, &data->info);
 }

 MODULE_DEVICE_TABLE(i2c, fsp3y_id);

 static struct i2c_driver fsp3y_driver = {
 	.driver = {
 		   .name = "fsp3y",
 		   },
 	.probe = fsp3y_probe,
 	.id_table = fsp3y_id
 };

 module_i2c_driver(fsp3y_driver);

 MODULE_AUTHOR("Václav Kubernát");
 MODULE_DESCRIPTION("PMBus driver for FSP/3Y-Power power supplies");
 MODULE_LICENSE("GPL");
 MODULE_IMPORT_NS(PMBUS);
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* Hardware monitoring driver for FSP 3Y-Power PSUs
	*
	* Copyright (c) 2021 Václav Kubernát, CESNET
	*
	* This driver is mostly reverse engineered with the help of a tool called pmbus_peek written by
	* David Brownell (and later adopted by Jan Kundrát). The device has some sort of a timing issue
	* when switching pages, details are explained in the code. The driver support is limited. It
	* exposes only the values, that have been tested to work correctly. Unsupported values either
	* aren't supported by the devices or their encondings are unknown.
	*/

	#include <linux/delay.h>
	#include <linux/i2c.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include "pmbus.h"

	#define YM2151_PAGE_12V_LOG 0x00
	#define YM2151_PAGE_12V_REAL 0x00
	#define YM2151_PAGE_5VSB_LOG 0x01
	#define YM2151_PAGE_5VSB_REAL 0x20
	#define YH5151E_PAGE_12V_LOG 0x00
	#define YH5151E_PAGE_12V_REAL 0x00
	#define YH5151E_PAGE_5V_LOG 0x01
	#define YH5151E_PAGE_5V_REAL 0x10
	#define YH5151E_PAGE_3V3_LOG 0x02
	#define YH5151E_PAGE_3V3_REAL 0x11

	enum chips {
	ym2151e,
	yh5151e
	};

	struct fsp3y_data {
	struct pmbus_driver_info info;
	int chip;
	int page;

	bool vout_linear_11;
	};

	#define to_fsp3y_data(x) container_of(x, struct fsp3y_data, info)

	static int page_log_to_page_real(int page_log, enum chips chip)
	{
	switch (chip) {
	case ym2151e:
	switch (page_log) {
	case YM2151_PAGE_12V_LOG:
	return YM2151_PAGE_12V_REAL;
	case YM2151_PAGE_5VSB_LOG:
	return YM2151_PAGE_5VSB_REAL;
	}
	return -EINVAL;
	case yh5151e:
	switch (page_log) {
	case YH5151E_PAGE_12V_LOG:
	return YH5151E_PAGE_12V_REAL;
	case YH5151E_PAGE_5V_LOG:
	return YH5151E_PAGE_5V_REAL;
	case YH5151E_PAGE_3V3_LOG:
	return YH5151E_PAGE_3V3_REAL;
	}
	return -EINVAL;
	}

	return -EINVAL;
	}

	static int set_page(struct i2c_client *client, int page_log)
	{
	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
	struct fsp3y_data *data = to_fsp3y_data(info);
	int rv;
	int page_real;

	if (page_log < 0)
	return 0;

	page_real = page_log_to_page_real(page_log, data->chip);
	if (page_real < 0)
	return page_real;

	if (data->page != page_real) {
	rv = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page_real);
	if (rv < 0)
	return rv;

	data->page = page_real;

	/*
	* Testing showed that the device has a timing issue. After
	* setting a page, it takes a while, before the device actually
	* gives the correct values from the correct page. 20 ms was
	* tested to be enough to not give wrong values (15 ms wasn't
	* enough).
	*/
	usleep_range(20000, 30000);
	}

	return 0;
	}

	static int fsp3y_read_byte_data(struct i2c_client *client, int page, int reg)
	{
	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
	struct fsp3y_data *data = to_fsp3y_data(info);
	int rv;

	/*
	* Inject an exponent for non-compliant YH5151-E.
	*/
	if (data->vout_linear_11 && reg == PMBUS_VOUT_MODE)
	return 0x1A;

	rv = set_page(client, page);
	if (rv < 0)
	return rv;

	return i2c_smbus_read_byte_data(client, reg);
	}

	static int fsp3y_read_word_data(struct i2c_client *client, int page, int phase, int reg)
	{
	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
	struct fsp3y_data *data = to_fsp3y_data(info);
	int rv;

	/*
	* This masks commands which weren't tested to work correctly. Some of
	* the masked commands return 0xFFFF. These would probably get tagged as
	* invalid by pmbus_core. Other ones do return values which might be
	* useful (that is, they are not 0xFFFF), but their encoding is unknown,
	* and so they are unsupported.
	*/
	switch (reg) {
	case PMBUS_READ_FAN_SPEED_1:
	case PMBUS_READ_IIN:
	case PMBUS_READ_IOUT:
	case PMBUS_READ_PIN:
	case PMBUS_READ_POUT:
	case PMBUS_READ_TEMPERATURE_1:
	case PMBUS_READ_TEMPERATURE_2:
	case PMBUS_READ_TEMPERATURE_3:
	case PMBUS_READ_VIN:
	case PMBUS_READ_VOUT:
	case PMBUS_STATUS_WORD:
	break;
	default:
	return -ENXIO;
	}

	rv = set_page(client, page);
	if (rv < 0)
	return rv;

	rv = i2c_smbus_read_word_data(client, reg);
	if (rv < 0)
	return rv;

	/*
	* Handle YH-5151E non-compliant linear11 vout voltage.
	*/
	if (data->vout_linear_11 && reg == PMBUS_READ_VOUT)
	rv = sign_extend32(rv, 10) & 0xffff;

	return rv;
	}

	static struct pmbus_driver_info fsp3y_info[] = {
	[ym2151e] = {
	.pages = 2,
	.func[YM2151_PAGE_12V_LOG] =
	PMBUS_HAVE_VOUT \| PMBUS_HAVE_IOUT \|
	PMBUS_HAVE_PIN \| PMBUS_HAVE_POUT \|
	PMBUS_HAVE_TEMP \| PMBUS_HAVE_TEMP2 \|
	PMBUS_HAVE_VIN \| PMBUS_HAVE_IIN \|
	PMBUS_HAVE_FAN12,
	.func[YM2151_PAGE_5VSB_LOG] =
	PMBUS_HAVE_VOUT \| PMBUS_HAVE_IOUT,
	.read_word_data = fsp3y_read_word_data,
	.read_byte_data = fsp3y_read_byte_data,
	},
	[yh5151e] = {
	.pages = 3,
	.func[YH5151E_PAGE_12V_LOG] =
	PMBUS_HAVE_VOUT \| PMBUS_HAVE_IOUT \|
	PMBUS_HAVE_POUT \|
	PMBUS_HAVE_TEMP \| PMBUS_HAVE_TEMP2 \| PMBUS_HAVE_TEMP3,
	.func[YH5151E_PAGE_5V_LOG] =
	PMBUS_HAVE_VOUT \| PMBUS_HAVE_IOUT \|
	PMBUS_HAVE_POUT,
	.func[YH5151E_PAGE_3V3_LOG] =
	PMBUS_HAVE_VOUT \| PMBUS_HAVE_IOUT \|
	PMBUS_HAVE_POUT,
	.read_word_data = fsp3y_read_word_data,
	.read_byte_data = fsp3y_read_byte_data,
	}
	};

	static int fsp3y_detect(struct i2c_client *client)
	{
	int rv;
	u8 buf[I2C_SMBUS_BLOCK_MAX + 1];

	rv = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
	if (rv < 0)
	return rv;

	buf[rv] = '\0';

	if (rv == 8) {
	if (!strcmp(buf, "YM-2151E"))
	return ym2151e;
	else if (!strcmp(buf, "YH-5151E"))
	return yh5151e;
	}

	dev_err(&client->dev, "Unsupported model %.*s\n", rv, buf);
	return -ENODEV;
	}

	static const struct i2c_device_id fsp3y_id[] = {
	{"ym2151e", ym2151e},
	{"yh5151e", yh5151e},
	{ }
	};

	static int fsp3y_probe(struct i2c_client *client)
	{
	struct fsp3y_data *data;
	const struct i2c_device_id *id;
	int rv;

	data = devm_kzalloc(&client->dev, sizeof(struct fsp3y_data), GFP_KERNEL);
	if (!data)
	return -ENOMEM;

	data->chip = fsp3y_detect(client);
	if (data->chip < 0)
	return data->chip;

	id = i2c_match_id(fsp3y_id, client);
	if (data->chip != id->driver_data)
	dev_warn(&client->dev, "Device mismatch: Configured %s (%d), detected %d\n",
	id->name, (int)id->driver_data, data->chip);

	rv = i2c_smbus_read_byte_data(client, PMBUS_PAGE);
	if (rv < 0)
	return rv;
	data->page = rv;

	data->info = fsp3y_info[data->chip];

	/*
	* YH-5151E sometimes reports vout in linear11 and sometimes in
	* linear16. This depends on the exact individual piece of hardware. One
	* YH-5151E can use linear16 and another might use linear11 instead.
	*
	* The format can be recognized by reading VOUT_MODE - if it doesn't
	* report a valid exponent, then vout uses linear11. Otherwise, the
	* device is compliant and uses linear16.
	*/
	data->vout_linear_11 = false;
	if (data->chip == yh5151e) {
	rv = i2c_smbus_read_byte_data(client, PMBUS_VOUT_MODE);
	if (rv < 0)
	return rv;

	if (rv == 0xFF)
	data->vout_linear_11 = true;
	}

	return pmbus_do_probe(client, &data->info);
	}

	MODULE_DEVICE_TABLE(i2c, fsp3y_id);

	static struct i2c_driver fsp3y_driver = {
	.driver = {
	.name = "fsp3y",
	},
	.probe = fsp3y_probe,
	.id_table = fsp3y_id
	};

	module_i2c_driver(fsp3y_driver);

	MODULE_AUTHOR("Václav Kubernát");
	MODULE_DESCRIPTION("PMBus driver for FSP/3Y-Power power supplies");
	MODULE_LICENSE("GPL");
	MODULE_IMPORT_NS(PMBUS);