Commit e10d9e4c authored by Guenter Roeck's avatar Guenter Roeck
Browse files

hwmon: (pmbus) Add support for Analog Devices LT7182S 



Add support for Analog Devices LT7182S Dual Channel 6A, 20V PolyPhase
Step-Down Silent Switcher with Digital Power System Management.

Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 5e9caf86

Documentation/hwmon/index.rst

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@@ -109,6 +109,7 @@ Hardware Monitoring Kernel Drivers 
   lm95234

   lm95245

   lochnagar

   lt7182s

   ltc2992

   ltc2945

   ltc2947

Documentation/hwmon/lt7182s.rst

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.. SPDX-License-Identifier: GPL-2.0



Kernel driver lt7182s

=====================



Supported chips:



  * ADI LT7182S



    Prefix: 'lt7182s'



    Addresses scanned: -



    Datasheet: https://www.analog.com/en/products/lt7182s.html



Author: Guenter Roeck <linux@roeck-us.net>





Description

-----------



LT7182S is a Dual Channel 6A, 20V PolyPhase Step-Down Silent Switcher with

Digital Power System Management support.





Usage Notes

-----------



This driver does not probe for PMBus devices. You will have to instantiate

devices explicitly.



Example: the following commands will load the driver for a LT7182S

at address 0x4f on I2C bus #4::



    # modprobe lt7182s

    # echo lt7182s 0x4f > /sys/bus/i2c/devices/i2c-4/new_device



It can also be instantiated by declaring an entry in device tree.





Sysfs attributes

----------------



======================= ====================================

curr[1-2]_label		"iin[12]"

curr[1-2]_input		Measured input current

curr[1-2]_max		Maximum input current

curr[1-2]_max_alarm	Current high alarm



curr[3-4]_label		"iout[1-2]"

curr[3-4]_input		Measured output current

curr[3-4]_highest	Highest measured output current

curr[3-4]_max		Maximum output current

curr[3-4]_max_alarm	Output current high alarm



in[1-2]_label		"vin[12]"

in[1-2]_input		Measured input voltage

in[1-2]_highest		Highest measured input voltage

in[1-2]_crit		Critical maximum input voltage

in[1-2]_crit_alarm	Input voltage critical high alarm

in[1-2]_min		Minimum input voltage

in[1-2]_min_alarm	Input voltage low alarm

in[1-2]_rated_min	Rated minimum input voltage

in[1-2]_rated_max	Rated maximum input voltage

in1_reset_history	Write to reset history for all attributes



in[3-5]_label		"vmon[1-3]"

in[3-5]_input		Measured voltage on ITH1/ITH2/EXTVCC pins

			Only available if enabled with MFR_ADC_CONTROL_LT7182S

			command.



in[3-4|6-7]_label	"vout[1-2]"

in[3-4|6-7]_input	Measured output voltage

in[3-4|6-7]_highest	Highest measured output voltage

in[3-4|6-7]_lcrit	Critical minimum output voltage

in[3-4|6-7]_lcrit_alarm	Output voltage critical low alarm

in[3-4|6-7]_min		Minimum output voltage

in[3-4|6-7]_max_alarm	Output voltage low alarm

in[3-4|6-7]_max		Maximum output voltage

in[3-4|6-7]_max_alarm	Output voltage high alarm

in[3-4|6-7]_crit	Critical maximum output voltage

in[3-4|6-7]_crit_alarm	Output voltage critical high alarm



power[1-2]_label	"pout[1-2]"

power[1-2]_input	Measured output power



temp1_input		Measured temperature

temp1_crit		Critical high temperature

temp1_crit_alarm	Chip temperature critical high alarm

temp1_max		Maximum temperature

temp1_max_alarm		Chip temperature high alarm

======================= ====================================

drivers/hwmon/pmbus/Kconfig

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@@ -181,6 +181,15 @@ config SENSORS_LM25066_REGULATOR 
	  If you say yes here you get regulator support for National

	  Semiconductor LM25066, LM5064, and LM5066.



config SENSORS_LT7182S

	tristate "Analog Devices LT7182S"

	help

	  If you say yes here you get hardware monitoring support for Analog

	  Devices LT7182S.



	  This driver can also be built as a module. If so, the module will

	  be called lt7182s.



config SENSORS_LTC2978

	tristate "Linear Technologies LTC2978 and compatibles"

	help

drivers/hwmon/pmbus/Makefile

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@@ -20,6 +20,7 @@ obj-$(CONFIG_SENSORS_IR38064) += ir38064.o 
obj-$(CONFIG_SENSORS_IRPS5401)	+= irps5401.o

obj-$(CONFIG_SENSORS_ISL68137)	+= isl68137.o

obj-$(CONFIG_SENSORS_LM25066)	+= lm25066.o

obj-$(CONFIG_SENSORS_LT7182S)	+= lt7182s.o

obj-$(CONFIG_SENSORS_LTC2978)	+= ltc2978.o

obj-$(CONFIG_SENSORS_LTC3815)	+= ltc3815.o

obj-$(CONFIG_SENSORS_MAX15301)	+= max15301.o

drivers/hwmon/pmbus/lt7182s.c

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// SPDX-License-Identifier: GPL-2.0+

/*

 * Hardware monitoring driver for Analog Devices LT7182S

 *

 * Copyright (c) 2022 Guenter Roeck

 *

 */



#include <linux/bits.h>

#include <linux/err.h>

#include <linux/i2c.h>

#include <linux/init.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/of.h>

#include "pmbus.h"



#define LT7182S_NUM_PAGES	2



#define MFR_READ_EXTVCC		0xcd

#define MFR_READ_ITH		0xce

#define MFR_CONFIG_ALL_LT7182S	0xd1

#define MFR_IOUT_PEAK		0xd7

#define MFR_ADC_CONTROL_LT7182S 0xd8



#define MFR_DEBUG_TELEMETRY	BIT(0)



#define MFR_VOUT_PEAK		0xdd

#define MFR_VIN_PEAK		0xde

#define MFR_TEMPERATURE_1_PEAK	0xdf

#define MFR_CLEAR_PEAKS		0xe3



#define MFR_CONFIG_IEEE		BIT(8)



static int lt7182s_read_word_data(struct i2c_client *client, int page, int phase, int reg)

{

	int ret;



	switch (reg) {

	case PMBUS_VIRT_READ_VMON:

		if (page == 0 || page == 1)

			ret = pmbus_read_word_data(client, page, phase, MFR_READ_ITH);

		else

			ret = pmbus_read_word_data(client, 0, phase, MFR_READ_EXTVCC);

		break;

	case PMBUS_VIRT_READ_IOUT_MAX:

		ret = pmbus_read_word_data(client, page, phase, MFR_IOUT_PEAK);

		break;

	case PMBUS_VIRT_READ_VOUT_MAX:

		ret = pmbus_read_word_data(client, page, phase, MFR_VOUT_PEAK);

		break;

	case PMBUS_VIRT_READ_VIN_MAX:

		ret = pmbus_read_word_data(client, page, phase, MFR_VIN_PEAK);

		break;

	case PMBUS_VIRT_READ_TEMP_MAX:

		ret = pmbus_read_word_data(client, page, phase, MFR_TEMPERATURE_1_PEAK);

		break;

	case PMBUS_VIRT_RESET_VIN_HISTORY:

		ret = (page == 0) ? 0 : -ENODATA;

		break;

	default:

		ret = -ENODATA;

		break;

	}

	return ret;

}



static int lt7182s_write_word_data(struct i2c_client *client, int page, int reg, u16 word)

{

	int ret;



	switch (reg) {

	case PMBUS_VIRT_RESET_VIN_HISTORY:

		ret = pmbus_write_byte(client, 0, MFR_CLEAR_PEAKS);

		break;

	default:

		ret = -ENODATA;

		break;

	}

	return ret;

}



static struct pmbus_driver_info lt7182s_info = {

	.pages = LT7182S_NUM_PAGES,

	.format[PSC_VOLTAGE_IN] = linear,

	.format[PSC_VOLTAGE_OUT] = linear,

	.format[PSC_CURRENT_IN] = linear,

	.format[PSC_CURRENT_OUT] = linear,

	.format[PSC_TEMPERATURE] = linear,

	.format[PSC_POWER] = linear,

	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT |

	  PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT |

	  PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |

	  PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,

	.func[1] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT |

	  PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT |

	  PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |

	  PMBUS_HAVE_STATUS_INPUT,

	.read_word_data = lt7182s_read_word_data,

	.write_word_data = lt7182s_write_word_data,

};



static int lt7182s_probe(struct i2c_client *client)

{

	struct device *dev = &client->dev;

	struct pmbus_driver_info *info;

	u8 buf[I2C_SMBUS_BLOCK_MAX + 1];

	int ret;



	if (!i2c_check_functionality(client->adapter,

				     I2C_FUNC_SMBUS_READ_BYTE_DATA |

				     I2C_FUNC_SMBUS_READ_WORD_DATA |

				     I2C_FUNC_SMBUS_READ_BLOCK_DATA))

		return -ENODEV;



	ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);

	if (ret < 0) {

		dev_err(dev, "Failed to read PMBUS_MFR_ID\n");

		return ret;

	}

	if (ret != 3 || strncmp(buf, "ADI", 3)) {

		buf[ret] = '\0';

		dev_err(dev, "Manufacturer '%s' not supported\n", buf);

		return -ENODEV;

	}



	ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);

	if (ret < 0) {

		dev_err(dev, "Failed to read PMBUS_MFR_MODEL\n");

		return ret;

	}

	if (ret != 7 || strncmp(buf, "LT7182S", 7)) {

		buf[ret] = '\0';

		dev_err(dev, "Model '%s' not supported\n", buf);

		return -ENODEV;

	}



	info = devm_kmemdup(dev, &lt7182s_info,

			    sizeof(struct pmbus_driver_info), GFP_KERNEL);

	if (!info)

		return -ENOMEM;



	/* Set data format to IEEE754 if configured */

	ret = i2c_smbus_read_word_data(client, MFR_CONFIG_ALL_LT7182S);

	if (ret < 0)

		return ret;

	if (ret & MFR_CONFIG_IEEE) {

		info->format[PSC_VOLTAGE_IN] = ieee754;

		info->format[PSC_VOLTAGE_OUT] = ieee754;

		info->format[PSC_CURRENT_IN] = ieee754;

		info->format[PSC_CURRENT_OUT] = ieee754;

		info->format[PSC_TEMPERATURE] = ieee754;

		info->format[PSC_POWER] = ieee754;

	}



	/* Enable VMON output if configured */

	ret = i2c_smbus_read_byte_data(client, MFR_ADC_CONTROL_LT7182S);

	if (ret < 0)

		return ret;

	if (ret & MFR_DEBUG_TELEMETRY) {

		info->pages = 3;

		info->func[0] |= PMBUS_HAVE_VMON;

		info->func[1] |= PMBUS_HAVE_VMON;

		info->func[2] = PMBUS_HAVE_VMON;

	}



	return pmbus_do_probe(client, info);

}



static const struct i2c_device_id lt7182s_id[] = {

	{ "lt7182s", 0 },

	{}

};

MODULE_DEVICE_TABLE(i2c, lt7182s_id);



static const struct of_device_id __maybe_unused lt7182s_of_match[] = {

	{ .compatible = "adi,lt7182s" },

	{}

};



static struct i2c_driver lt7182s_driver = {

	.driver = {

		.name = "lt7182s",

		.of_match_table = of_match_ptr(lt7182s_of_match),

	},

	.probe_new = lt7182s_probe,

	.id_table = lt7182s_id,

};



module_i2c_driver(lt7182s_driver);



MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");

MODULE_DESCRIPTION("PMBus driver for Analog Devices LT7182S");

MODULE_LICENSE("GPL");

MODULE_IMPORT_NS(PMBUS);