[mirror_ubuntu-bionic-kernel.git] / drivers / hwmon / ina3221.c

/*
 * INA3221 Triple Current/Voltage Monitor
 *
 * Copyright (C) 2016 Texas Instruments Incorporated - http://www.ti.com/
 *	Andrew F. Davis <afd@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 */

#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/regmap.h>

#define INA3221_DRIVER_NAME		"ina3221"

#define INA3221_CONFIG			0x00
#define INA3221_SHUNT1			0x01
#define INA3221_BUS1			0x02
#define INA3221_SHUNT2			0x03
#define INA3221_BUS2			0x04
#define INA3221_SHUNT3			0x05
#define INA3221_BUS3			0x06
#define INA3221_CRIT1			0x07
#define INA3221_WARN1			0x08
#define INA3221_CRIT2			0x09
#define INA3221_WARN2			0x0a
#define INA3221_CRIT3			0x0b
#define INA3221_WARN3			0x0c
#define INA3221_MASK_ENABLE		0x0f

#define INA3221_CONFIG_MODE_SHUNT	BIT(1)
#define INA3221_CONFIG_MODE_BUS		BIT(2)
#define INA3221_CONFIG_MODE_CONTINUOUS	BIT(3)

#define INA3221_RSHUNT_DEFAULT		10000

enum ina3221_fields {
	/* Configuration */
	F_RST,

	/* Alert Flags */
	F_WF3, F_WF2, F_WF1,
	F_CF3, F_CF2, F_CF1,

	/* sentinel */
	F_MAX_FIELDS
};

static const struct reg_field ina3221_reg_fields[] = {
	[F_RST] = REG_FIELD(INA3221_CONFIG, 15, 15),

	[F_WF3] = REG_FIELD(INA3221_MASK_ENABLE, 3, 3),
	[F_WF2] = REG_FIELD(INA3221_MASK_ENABLE, 4, 4),
	[F_WF1] = REG_FIELD(INA3221_MASK_ENABLE, 5, 5),
	[F_CF3] = REG_FIELD(INA3221_MASK_ENABLE, 7, 7),
	[F_CF2] = REG_FIELD(INA3221_MASK_ENABLE, 8, 8),
	[F_CF1] = REG_FIELD(INA3221_MASK_ENABLE, 9, 9),
};

enum ina3221_channels {
	INA3221_CHANNEL1,
	INA3221_CHANNEL2,
	INA3221_CHANNEL3,
	INA3221_NUM_CHANNELS
};

static const unsigned int register_channel[] = {
	[INA3221_SHUNT1] = INA3221_CHANNEL1,
	[INA3221_SHUNT2] = INA3221_CHANNEL2,
	[INA3221_SHUNT3] = INA3221_CHANNEL3,
	[INA3221_CRIT1] = INA3221_CHANNEL1,
	[INA3221_CRIT2] = INA3221_CHANNEL2,
	[INA3221_CRIT3] = INA3221_CHANNEL3,
	[INA3221_WARN1] = INA3221_CHANNEL1,
	[INA3221_WARN2] = INA3221_CHANNEL2,
	[INA3221_WARN3] = INA3221_CHANNEL3,
};

/**
 * struct ina3221_data - device specific information
 * @regmap: Register map of the device
 * @fields: Register fields of the device
 * @shunt_resistors: Array of resistor values per channel
 */
struct ina3221_data {
	struct regmap *regmap;
	struct regmap_field *fields[F_MAX_FIELDS];
	int shunt_resistors[INA3221_NUM_CHANNELS];
};

static int ina3221_read_value(struct ina3221_data *ina, unsigned int reg,
			      int *val)
{
	unsigned int regval;
	int ret;

	ret = regmap_read(ina->regmap, reg, &regval);
	if (ret)
		return ret;

	*val = sign_extend32(regval >> 3, 12);

	return 0;
}

static ssize_t ina3221_show_bus_voltage(struct device *dev,
					struct device_attribute *attr,
					char *buf)
{
	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	struct ina3221_data *ina = dev_get_drvdata(dev);
	unsigned int reg = sd_attr->index;
	int val, voltage_mv, ret;

	ret = ina3221_read_value(ina, reg, &val);
	if (ret)
		return ret;

	voltage_mv = val * 8;

	return snprintf(buf, PAGE_SIZE, "%d\n", voltage_mv);
}

static ssize_t ina3221_show_shunt_voltage(struct device *dev,
					  struct device_attribute *attr,
					  char *buf)
{
	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	struct ina3221_data *ina = dev_get_drvdata(dev);
	unsigned int reg = sd_attr->index;
	int val, voltage_uv, ret;

	ret = ina3221_read_value(ina, reg, &val);
	if (ret)
		return ret;
	voltage_uv = val * 40;

	return snprintf(buf, PAGE_SIZE, "%d\n", voltage_uv);
}

static ssize_t ina3221_show_current(struct device *dev,
				    struct device_attribute *attr, char *buf)
{
	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	struct ina3221_data *ina = dev_get_drvdata(dev);
	unsigned int reg = sd_attr->index;
	unsigned int channel = register_channel[reg];
	int resistance_uo = ina->shunt_resistors[channel];
	int val, current_ma, voltage_nv, ret;

	ret = ina3221_read_value(ina, reg, &val);
	if (ret)
		return ret;
	voltage_nv = val * 40000;

	current_ma = DIV_ROUND_CLOSEST(voltage_nv, resistance_uo);

	return snprintf(buf, PAGE_SIZE, "%d\n", current_ma);
}

static ssize_t ina3221_set_current(struct device *dev,
				   struct device_attribute *attr,
				   const char *buf, size_t count)
{
	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	struct ina3221_data *ina = dev_get_drvdata(dev);
	unsigned int reg = sd_attr->index;
	unsigned int channel = register_channel[reg];
	int resistance_uo = ina->shunt_resistors[channel];
	int val, current_ma, voltage_uv, ret;

	ret = kstrtoint(buf, 0, &current_ma);
	if (ret)
		return ret;

	/* clamp current */
	current_ma = clamp_val(current_ma,
			       INT_MIN / resistance_uo,
			       INT_MAX / resistance_uo);

	voltage_uv = DIV_ROUND_CLOSEST(current_ma * resistance_uo, 1000);

	/* clamp voltage */
	voltage_uv = clamp_val(voltage_uv, -163800, 163800);

	/* 1 / 40uV(scale) << 3(register shift) = 5 */
	val = DIV_ROUND_CLOSEST(voltage_uv, 5) & 0xfff8;

	ret = regmap_write(ina->regmap, reg, val);
	if (ret)
		return ret;

	return count;
}

static ssize_t ina3221_show_shunt(struct device *dev,
				  struct device_attribute *attr, char *buf)
{
	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	struct ina3221_data *ina = dev_get_drvdata(dev);
	unsigned int channel = sd_attr->index;
	unsigned int resistance_uo;

	resistance_uo = ina->shunt_resistors[channel];

	return snprintf(buf, PAGE_SIZE, "%d\n", resistance_uo);
}

static ssize_t ina3221_set_shunt(struct device *dev,
				 struct device_attribute *attr,
				 const char *buf, size_t count)
{
	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	struct ina3221_data *ina = dev_get_drvdata(dev);
	unsigned int channel = sd_attr->index;
	int val;
	int ret;

	ret = kstrtoint(buf, 0, &val);
	if (ret)
		return ret;

	val = clamp_val(val, 1, INT_MAX);

	ina->shunt_resistors[channel] = val;

	return count;
}

static ssize_t ina3221_show_alert(struct device *dev,
				  struct device_attribute *attr, char *buf)
{
	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	struct ina3221_data *ina = dev_get_drvdata(dev);
	unsigned int field = sd_attr->index;
	unsigned int regval;
	int ret;

	ret = regmap_field_read(ina->fields[field], &regval);
	if (ret)
		return ret;

	return snprintf(buf, PAGE_SIZE, "%d\n", regval);
}

/* bus voltage */
static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO,
		ina3221_show_bus_voltage, NULL, INA3221_BUS1);
static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO,
		ina3221_show_bus_voltage, NULL, INA3221_BUS2);
static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO,
		ina3221_show_bus_voltage, NULL, INA3221_BUS3);

/* calculated current */
static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO,
		ina3221_show_current, NULL, INA3221_SHUNT1);
static SENSOR_DEVICE_ATTR(curr2_input, S_IRUGO,
		ina3221_show_current, NULL, INA3221_SHUNT2);
static SENSOR_DEVICE_ATTR(curr3_input, S_IRUGO,
		ina3221_show_current, NULL, INA3221_SHUNT3);

/* shunt resistance */
static SENSOR_DEVICE_ATTR(shunt1_resistor, S_IRUGO | S_IWUSR,
		ina3221_show_shunt, ina3221_set_shunt, INA3221_CHANNEL1);
static SENSOR_DEVICE_ATTR(shunt2_resistor, S_IRUGO | S_IWUSR,
		ina3221_show_shunt, ina3221_set_shunt, INA3221_CHANNEL2);
static SENSOR_DEVICE_ATTR(shunt3_resistor, S_IRUGO | S_IWUSR,
		ina3221_show_shunt, ina3221_set_shunt, INA3221_CHANNEL3);

/* critical current */
static SENSOR_DEVICE_ATTR(curr1_crit, S_IRUGO | S_IWUSR,
		ina3221_show_current, ina3221_set_current, INA3221_CRIT1);
static SENSOR_DEVICE_ATTR(curr2_crit, S_IRUGO | S_IWUSR,
		ina3221_show_current, ina3221_set_current, INA3221_CRIT2);
static SENSOR_DEVICE_ATTR(curr3_crit, S_IRUGO | S_IWUSR,
		ina3221_show_current, ina3221_set_current, INA3221_CRIT3);

/* critical current alert */
static SENSOR_DEVICE_ATTR(curr1_crit_alarm, S_IRUGO,
		ina3221_show_alert, NULL, F_CF1);
static SENSOR_DEVICE_ATTR(curr2_crit_alarm, S_IRUGO,
		ina3221_show_alert, NULL, F_CF2);
static SENSOR_DEVICE_ATTR(curr3_crit_alarm, S_IRUGO,
		ina3221_show_alert, NULL, F_CF3);

/* warning current */
static SENSOR_DEVICE_ATTR(curr1_max, S_IRUGO | S_IWUSR,
		ina3221_show_current, ina3221_set_current, INA3221_WARN1);
static SENSOR_DEVICE_ATTR(curr2_max, S_IRUGO | S_IWUSR,
		ina3221_show_current, ina3221_set_current, INA3221_WARN2);
static SENSOR_DEVICE_ATTR(curr3_max, S_IRUGO | S_IWUSR,
		ina3221_show_current, ina3221_set_current, INA3221_WARN3);

/* warning current alert */
static SENSOR_DEVICE_ATTR(curr1_max_alarm, S_IRUGO,
		ina3221_show_alert, NULL, F_WF1);
static SENSOR_DEVICE_ATTR(curr2_max_alarm, S_IRUGO,
		ina3221_show_alert, NULL, F_WF2);
static SENSOR_DEVICE_ATTR(curr3_max_alarm, S_IRUGO,
		ina3221_show_alert, NULL, F_WF3);

/* shunt voltage */
static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO,
		ina3221_show_shunt_voltage, NULL, INA3221_SHUNT1);
static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO,
		ina3221_show_shunt_voltage, NULL, INA3221_SHUNT2);
static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO,
		ina3221_show_shunt_voltage, NULL, INA3221_SHUNT3);

static struct attribute *ina3221_attrs[] = {
	/* channel 1 */
	&sensor_dev_attr_in1_input.dev_attr.attr,
	&sensor_dev_attr_curr1_input.dev_attr.attr,
	&sensor_dev_attr_shunt1_resistor.dev_attr.attr,
	&sensor_dev_attr_curr1_crit.dev_attr.attr,
	&sensor_dev_attr_curr1_crit_alarm.dev_attr.attr,
	&sensor_dev_attr_curr1_max.dev_attr.attr,
	&sensor_dev_attr_curr1_max_alarm.dev_attr.attr,
	&sensor_dev_attr_in4_input.dev_attr.attr,

	/* channel 2 */
	&sensor_dev_attr_in2_input.dev_attr.attr,
	&sensor_dev_attr_curr2_input.dev_attr.attr,
	&sensor_dev_attr_shunt2_resistor.dev_attr.attr,
	&sensor_dev_attr_curr2_crit.dev_attr.attr,
	&sensor_dev_attr_curr2_crit_alarm.dev_attr.attr,
	&sensor_dev_attr_curr2_max.dev_attr.attr,
	&sensor_dev_attr_curr2_max_alarm.dev_attr.attr,
	&sensor_dev_attr_in5_input.dev_attr.attr,

	/* channel 3 */
	&sensor_dev_attr_in3_input.dev_attr.attr,
	&sensor_dev_attr_curr3_input.dev_attr.attr,
	&sensor_dev_attr_shunt3_resistor.dev_attr.attr,
	&sensor_dev_attr_curr3_crit.dev_attr.attr,
	&sensor_dev_attr_curr3_crit_alarm.dev_attr.attr,
	&sensor_dev_attr_curr3_max.dev_attr.attr,
	&sensor_dev_attr_curr3_max_alarm.dev_attr.attr,
	&sensor_dev_attr_in6_input.dev_attr.attr,

	NULL,
};
ATTRIBUTE_GROUPS(ina3221);

static const struct regmap_range ina3221_yes_ranges[] = {
	regmap_reg_range(INA3221_SHUNT1, INA3221_BUS3),
	regmap_reg_range(INA3221_MASK_ENABLE, INA3221_MASK_ENABLE),
};

static const struct regmap_access_table ina3221_volatile_table = {
	.yes_ranges = ina3221_yes_ranges,
	.n_yes_ranges = ARRAY_SIZE(ina3221_yes_ranges),
};

static const struct regmap_config ina3221_regmap_config = {
	.reg_bits = 8,
	.val_bits = 16,

	.cache_type = REGCACHE_RBTREE,
	.volatile_table = &ina3221_volatile_table,
};

static int ina3221_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct device *dev = &client->dev;
	struct ina3221_data *ina;
	struct device *hwmon_dev;
	int i, ret;

	ina = devm_kzalloc(dev, sizeof(*ina), GFP_KERNEL);
	if (!ina)
		return -ENOMEM;

	ina->regmap = devm_regmap_init_i2c(client, &ina3221_regmap_config);
	if (IS_ERR(ina->regmap)) {
		dev_err(dev, "Unable to allocate register map\n");
		return PTR_ERR(ina->regmap);
	}

	for (i = 0; i < F_MAX_FIELDS; i++) {
		ina->fields[i] = devm_regmap_field_alloc(dev,
							 ina->regmap,
							 ina3221_reg_fields[i]);
		if (IS_ERR(ina->fields[i])) {
			dev_err(dev, "Unable to allocate regmap fields\n");
			return PTR_ERR(ina->fields[i]);
		}
	}

	for (i = 0; i < INA3221_NUM_CHANNELS; i++)
		ina->shunt_resistors[i] = INA3221_RSHUNT_DEFAULT;

	ret = regmap_field_write(ina->fields[F_RST], true);
	if (ret) {
		dev_err(dev, "Unable to reset device\n");
		return ret;
	}

	hwmon_dev = devm_hwmon_device_register_with_groups(dev,
							   client->name,
							   ina, ina3221_groups);
	if (IS_ERR(hwmon_dev)) {
		dev_err(dev, "Unable to register hwmon device\n");
		return PTR_ERR(hwmon_dev);
	}

	return 0;
}

static const struct of_device_id ina3221_of_match_table[] = {
	{ .compatible = "ti,ina3221", },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, ina3221_of_match_table);

static const struct i2c_device_id ina3221_ids[] = {
	{ "ina3221", 0 },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(i2c, ina3221_ids);

static struct i2c_driver ina3221_i2c_driver = {
	.probe = ina3221_probe,
	.driver = {
		.name = INA3221_DRIVER_NAME,
		.of_match_table = ina3221_of_match_table,
	},
	.id_table = ina3221_ids,
};
module_i2c_driver(ina3221_i2c_driver);

MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
MODULE_DESCRIPTION("Texas Instruments INA3221 HWMon Driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
7cb6dcff AD	1	/*
	2	* INA3221 Triple Current/Voltage Monitor
	3	*
	4	* Copyright (C) 2016 Texas Instruments Incorporated - http://www.ti.com/
	5	* Andrew F. Davis <afd@ti.com>
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*
	11	* This program is distributed in the hope that it will be useful, but
	12	* WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	* General Public License for more details.
	15	*/
	16
	17	#include <linux/hwmon.h>
	18	#include <linux/hwmon-sysfs.h>
	19	#include <linux/i2c.h>
	20	#include <linux/module.h>
	21	#include <linux/of.h>
	22	#include <linux/regmap.h>
	23
	24	#define INA3221_DRIVER_NAME "ina3221"
	25
	26	#define INA3221_CONFIG 0x00
	27	#define INA3221_SHUNT1 0x01
	28	#define INA3221_BUS1 0x02
	29	#define INA3221_SHUNT2 0x03
	30	#define INA3221_BUS2 0x04
	31	#define INA3221_SHUNT3 0x05
	32	#define INA3221_BUS3 0x06
	33	#define INA3221_CRIT1 0x07
	34	#define INA3221_WARN1 0x08
	35	#define INA3221_CRIT2 0x09
	36	#define INA3221_WARN2 0x0a
	37	#define INA3221_CRIT3 0x0b
	38	#define INA3221_WARN3 0x0c
	39	#define INA3221_MASK_ENABLE 0x0f
	40
	41	#define INA3221_CONFIG_MODE_SHUNT BIT(1)
	42	#define INA3221_CONFIG_MODE_BUS BIT(2)
	43	#define INA3221_CONFIG_MODE_CONTINUOUS BIT(3)
	44
	45	#define INA3221_RSHUNT_DEFAULT 10000
	46
	47	enum ina3221_fields {
	48	/* Configuration */
	49	F_RST,
	50
	51	/* Alert Flags */
	52	F_WF3, F_WF2, F_WF1,
	53	F_CF3, F_CF2, F_CF1,
	54
	55	/* sentinel */
	56	F_MAX_FIELDS
	57	};
	58
	59	static const struct reg_field ina3221_reg_fields[] = {
	60	[F_RST] = REG_FIELD(INA3221_CONFIG, 15, 15),
	61
	62	[F_WF3] = REG_FIELD(INA3221_MASK_ENABLE, 3, 3),
	63	[F_WF2] = REG_FIELD(INA3221_MASK_ENABLE, 4, 4),
	64	[F_WF1] = REG_FIELD(INA3221_MASK_ENABLE, 5, 5),
65	[F_CF3] = REG_FIELD(INA3221_MASK_ENABLE, 7, 7),
66	[F_CF2] = REG_FIELD(INA3221_MASK_ENABLE, 8, 8),
67	[F_CF1] = REG_FIELD(INA3221_MASK_ENABLE, 9, 9),
68	};
69
70	enum ina3221_channels {
71	INA3221_CHANNEL1,
72	INA3221_CHANNEL2,
73	INA3221_CHANNEL3,
74	INA3221_NUM_CHANNELS
75	};
76
77	static const unsigned int register_channel[] = {
78	[INA3221_SHUNT1] = INA3221_CHANNEL1,
79	[INA3221_SHUNT2] = INA3221_CHANNEL2,
80	[INA3221_SHUNT3] = INA3221_CHANNEL3,
81	[INA3221_CRIT1] = INA3221_CHANNEL1,
82	[INA3221_CRIT2] = INA3221_CHANNEL2,
83	[INA3221_CRIT3] = INA3221_CHANNEL3,
84	[INA3221_WARN1] = INA3221_CHANNEL1,
85	[INA3221_WARN2] = INA3221_CHANNEL2,
86	[INA3221_WARN3] = INA3221_CHANNEL3,
87	};
88
89	/**
90	* struct ina3221_data - device specific information
91	* @regmap: Register map of the device
92	* @fields: Register fields of the device
93	* @shunt_resistors: Array of resistor values per channel
94	*/
95	struct ina3221_data {
96	struct regmap *regmap;
97	struct regmap_field *fields[F_MAX_FIELDS];
9ad0df1a	98	int shunt_resistors[INA3221_NUM_CHANNELS];
7cb6dcff AD	99	};
	100
	101	static int ina3221_read_value(struct ina3221_data *ina, unsigned int reg,
	102	int *val)
	103	{
	104	unsigned int regval;
	105	int ret;
	106
	107	ret = regmap_read(ina->regmap, reg, &regval);
	108	if (ret)
	109	return ret;
	110
	111	*val = sign_extend32(regval >> 3, 12);
	112
	113	return 0;
	114	}
	115
	116	static ssize_t ina3221_show_bus_voltage(struct device *dev,
	117	struct device_attribute *attr,
	118	char *buf)
	119	{
	120	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	121	struct ina3221_data *ina = dev_get_drvdata(dev);
	122	unsigned int reg = sd_attr->index;
	123	int val, voltage_mv, ret;
	124
	125	ret = ina3221_read_value(ina, reg, &val);
	126	if (ret)
	127	return ret;
	128
	129	voltage_mv = val * 8;
	130
	131	return snprintf(buf, PAGE_SIZE, "%d\n", voltage_mv);
	132	}
	133
	134	static ssize_t ina3221_show_shunt_voltage(struct device *dev,
	135	struct device_attribute *attr,
	136	char *buf)
	137	{
	138	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	139	struct ina3221_data *ina = dev_get_drvdata(dev);
	140	unsigned int reg = sd_attr->index;
	141	int val, voltage_uv, ret;
	142
	143	ret = ina3221_read_value(ina, reg, &val);
	144	if (ret)
	145	return ret;
	146	voltage_uv = val * 40;
	147
	148	return snprintf(buf, PAGE_SIZE, "%d\n", voltage_uv);
	149	}
	150
	151	static ssize_t ina3221_show_current(struct device *dev,
	152	struct device_attribute attr, char buf)
	153	{
	154	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	155	struct ina3221_data *ina = dev_get_drvdata(dev);
	156	unsigned int reg = sd_attr->index;
	157	unsigned int channel = register_channel[reg];
9ad0df1a	158	int resistance_uo = ina->shunt_resistors[channel];
7cb6dcff AD	159	int val, current_ma, voltage_nv, ret;
	160
	161	ret = ina3221_read_value(ina, reg, &val);
	162	if (ret)
	163	return ret;
	164	voltage_nv = val * 40000;
	165
	166	current_ma = DIV_ROUND_CLOSEST(voltage_nv, resistance_uo);
	167
	168	return snprintf(buf, PAGE_SIZE, "%d\n", current_ma);
	169	}
	170
	171	static ssize_t ina3221_set_current(struct device *dev,
	172	struct device_attribute *attr,
	173	const char *buf, size_t count)
	174	{
	175	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	176	struct ina3221_data *ina = dev_get_drvdata(dev);
	177	unsigned int reg = sd_attr->index;
	178	unsigned int channel = register_channel[reg];
9ad0df1a	179	int resistance_uo = ina->shunt_resistors[channel];
7cb6dcff AD	180	int val, current_ma, voltage_uv, ret;
	181
	182	ret = kstrtoint(buf, 0, &current_ma);
	183	if (ret)
	184	return ret;
	185
	186	/* clamp current */
	187	current_ma = clamp_val(current_ma,
	188	INT_MIN / resistance_uo,
	189	INT_MAX / resistance_uo);
	190
	191	voltage_uv = DIV_ROUND_CLOSEST(current_ma * resistance_uo, 1000);
	192
	193	/* clamp voltage */
	194	voltage_uv = clamp_val(voltage_uv, -163800, 163800);
	195
	196	/* 1 / 40uV(scale) << 3(register shift) = 5 */
	197	val = DIV_ROUND_CLOSEST(voltage_uv, 5) & 0xfff8;
	198
	199	ret = regmap_write(ina->regmap, reg, val);
	200	if (ret)
	201	return ret;
	202
	203	return count;
	204	}
	205
	206	static ssize_t ina3221_show_shunt(struct device *dev,
	207	struct device_attribute attr, char buf)
	208	{
	209	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	210	struct ina3221_data *ina = dev_get_drvdata(dev);
	211	unsigned int channel = sd_attr->index;
	212	unsigned int resistance_uo;
	213
	214	resistance_uo = ina->shunt_resistors[channel];
	215
	216	return snprintf(buf, PAGE_SIZE, "%d\n", resistance_uo);
	217	}
	218
	219	static ssize_t ina3221_set_shunt(struct device *dev,
	220	struct device_attribute *attr,
	221	const char *buf, size_t count)
	222	{
	223	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	224	struct ina3221_data *ina = dev_get_drvdata(dev);
	225	unsigned int channel = sd_attr->index;
9ad0df1a	226	int val;
7cb6dcff AD	227	int ret;
7cb6dcff AD	228
9ad0df1a	229	ret = kstrtoint(buf, 0, &val);
7cb6dcff AD	230	if (ret)
	231	return ret;
	232
9ad0df1a	233	val = clamp_val(val, 1, INT_MAX);
7cb6dcff AD	234
	235	ina->shunt_resistors[channel] = val;
	236
	237	return count;
	238	}
	239
	240	static ssize_t ina3221_show_alert(struct device *dev,
	241	struct device_attribute attr, char buf)
	242	{
	243	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
	244	struct ina3221_data *ina = dev_get_drvdata(dev);
	245	unsigned int field = sd_attr->index;
	246	unsigned int regval;
	247	int ret;
	248
	249	ret = regmap_field_read(ina->fields[field], &regval);
	250	if (ret)
	251	return ret;
	252
	253	return snprintf(buf, PAGE_SIZE, "%d\n", regval);
	254	}
	255
	256	/* bus voltage */
	257	static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO,
	258	ina3221_show_bus_voltage, NULL, INA3221_BUS1);
	259	static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO,
	260	ina3221_show_bus_voltage, NULL, INA3221_BUS2);
	261	static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO,
	262	ina3221_show_bus_voltage, NULL, INA3221_BUS3);
	263
	264	/* calculated current */
	265	static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO,
	266	ina3221_show_current, NULL, INA3221_SHUNT1);
	267	static SENSOR_DEVICE_ATTR(curr2_input, S_IRUGO,
	268	ina3221_show_current, NULL, INA3221_SHUNT2);
	269	static SENSOR_DEVICE_ATTR(curr3_input, S_IRUGO,
	270	ina3221_show_current, NULL, INA3221_SHUNT3);
	271
	272	/* shunt resistance */
	273	static SENSOR_DEVICE_ATTR(shunt1_resistor, S_IRUGO \| S_IWUSR,
	274	ina3221_show_shunt, ina3221_set_shunt, INA3221_CHANNEL1);
	275	static SENSOR_DEVICE_ATTR(shunt2_resistor, S_IRUGO \| S_IWUSR,
	276	ina3221_show_shunt, ina3221_set_shunt, INA3221_CHANNEL2);
	277	static SENSOR_DEVICE_ATTR(shunt3_resistor, S_IRUGO \| S_IWUSR,
	278	ina3221_show_shunt, ina3221_set_shunt, INA3221_CHANNEL3);
	279
	280	/* critical current */
	281	static SENSOR_DEVICE_ATTR(curr1_crit, S_IRUGO \| S_IWUSR,
	282	ina3221_show_current, ina3221_set_current, INA3221_CRIT1);
	283	static SENSOR_DEVICE_ATTR(curr2_crit, S_IRUGO \| S_IWUSR,
	284	ina3221_show_current, ina3221_set_current, INA3221_CRIT2);
	285	static SENSOR_DEVICE_ATTR(curr3_crit, S_IRUGO \| S_IWUSR,
	286	ina3221_show_current, ina3221_set_current, INA3221_CRIT3);
	287
	288	/* critical current alert */
	289	static SENSOR_DEVICE_ATTR(curr1_crit_alarm, S_IRUGO,
	290	ina3221_show_alert, NULL, F_CF1);
	291	static SENSOR_DEVICE_ATTR(curr2_crit_alarm, S_IRUGO,
	292	ina3221_show_alert, NULL, F_CF2);
	293	static SENSOR_DEVICE_ATTR(curr3_crit_alarm, S_IRUGO,
	294	ina3221_show_alert, NULL, F_CF3);
	295
	296	/* warning current */
	297	static SENSOR_DEVICE_ATTR(curr1_max, S_IRUGO \| S_IWUSR,
298	ina3221_show_current, ina3221_set_current, INA3221_WARN1);
299	static SENSOR_DEVICE_ATTR(curr2_max, S_IRUGO \| S_IWUSR,
300	ina3221_show_current, ina3221_set_current, INA3221_WARN2);
301	static SENSOR_DEVICE_ATTR(curr3_max, S_IRUGO \| S_IWUSR,
302	ina3221_show_current, ina3221_set_current, INA3221_WARN3);
303
304	/* warning current alert */
305	static SENSOR_DEVICE_ATTR(curr1_max_alarm, S_IRUGO,
306	ina3221_show_alert, NULL, F_WF1);
307	static SENSOR_DEVICE_ATTR(curr2_max_alarm, S_IRUGO,
308	ina3221_show_alert, NULL, F_WF2);
309	static SENSOR_DEVICE_ATTR(curr3_max_alarm, S_IRUGO,
310	ina3221_show_alert, NULL, F_WF3);
311
312	/* shunt voltage */
313	static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO,
314	ina3221_show_shunt_voltage, NULL, INA3221_SHUNT1);
315	static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO,
316	ina3221_show_shunt_voltage, NULL, INA3221_SHUNT2);
317	static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO,
318	ina3221_show_shunt_voltage, NULL, INA3221_SHUNT3);
319
320	static struct attribute *ina3221_attrs[] = {
321	/* channel 1 */
322	&sensor_dev_attr_in1_input.dev_attr.attr,
323	&sensor_dev_attr_curr1_input.dev_attr.attr,
324	&sensor_dev_attr_shunt1_resistor.dev_attr.attr,
325	&sensor_dev_attr_curr1_crit.dev_attr.attr,
326	&sensor_dev_attr_curr1_crit_alarm.dev_attr.attr,
327	&sensor_dev_attr_curr1_max.dev_attr.attr,
328	&sensor_dev_attr_curr1_max_alarm.dev_attr.attr,
329	&sensor_dev_attr_in4_input.dev_attr.attr,
330
331	/* channel 2 */
332	&sensor_dev_attr_in2_input.dev_attr.attr,
333	&sensor_dev_attr_curr2_input.dev_attr.attr,
334	&sensor_dev_attr_shunt2_resistor.dev_attr.attr,
335	&sensor_dev_attr_curr2_crit.dev_attr.attr,
336	&sensor_dev_attr_curr2_crit_alarm.dev_attr.attr,
337	&sensor_dev_attr_curr2_max.dev_attr.attr,
338	&sensor_dev_attr_curr2_max_alarm.dev_attr.attr,
339	&sensor_dev_attr_in5_input.dev_attr.attr,
340
341	/* channel 3 */
342	&sensor_dev_attr_in3_input.dev_attr.attr,
343	&sensor_dev_attr_curr3_input.dev_attr.attr,
344	&sensor_dev_attr_shunt3_resistor.dev_attr.attr,
345	&sensor_dev_attr_curr3_crit.dev_attr.attr,
346	&sensor_dev_attr_curr3_crit_alarm.dev_attr.attr,
347	&sensor_dev_attr_curr3_max.dev_attr.attr,
348	&sensor_dev_attr_curr3_max_alarm.dev_attr.attr,
349	&sensor_dev_attr_in6_input.dev_attr.attr,
350
351	NULL,
352	};
353	ATTRIBUTE_GROUPS(ina3221);
354
355	static const struct regmap_range ina3221_yes_ranges[] = {
356	regmap_reg_range(INA3221_SHUNT1, INA3221_BUS3),
357	regmap_reg_range(INA3221_MASK_ENABLE, INA3221_MASK_ENABLE),
358	};
359
360	static const struct regmap_access_table ina3221_volatile_table = {
361	.yes_ranges = ina3221_yes_ranges,
362	.n_yes_ranges = ARRAY_SIZE(ina3221_yes_ranges),
363	};
364
365	static const struct regmap_config ina3221_regmap_config = {
366	.reg_bits = 8,
367	.val_bits = 16,
368
369	.cache_type = REGCACHE_RBTREE,
370	.volatile_table = &ina3221_volatile_table,
371	};
372
373	static int ina3221_probe(struct i2c_client *client,
374	const struct i2c_device_id *id)
375	{
376	struct device *dev = &client->dev;
377	struct ina3221_data *ina;
378	struct device *hwmon_dev;
379	int i, ret;
380
381	ina = devm_kzalloc(dev, sizeof(*ina), GFP_KERNEL);
382	if (!ina)
383	return -ENOMEM;
384
385	ina->regmap = devm_regmap_init_i2c(client, &ina3221_regmap_config);
386	if (IS_ERR(ina->regmap)) {
387	dev_err(dev, "Unable to allocate register map\n");
388	return PTR_ERR(ina->regmap);
389	}
390
391	for (i = 0; i < F_MAX_FIELDS; i++) {
392	ina->fields[i] = devm_regmap_field_alloc(dev,
393	ina->regmap,
394	ina3221_reg_fields[i]);
395	if (IS_ERR(ina->fields[i])) {
396	dev_err(dev, "Unable to allocate regmap fields\n");
397	return PTR_ERR(ina->fields[i]);
398	}
399	}
400
401	for (i = 0; i < INA3221_NUM_CHANNELS; i++)
402	ina->shunt_resistors[i] = INA3221_RSHUNT_DEFAULT;
403
404	ret = regmap_field_write(ina->fields[F_RST], true);
405	if (ret) {
406	dev_err(dev, "Unable to reset device\n");
407	return ret;
408	}
409
410	hwmon_dev = devm_hwmon_device_register_with_groups(dev,
411	client->name,
412	ina, ina3221_groups);
413	if (IS_ERR(hwmon_dev)) {
414	dev_err(dev, "Unable to register hwmon device\n");
415	return PTR_ERR(hwmon_dev);
416	}
417
418	return 0;
419	}
420
421	static const struct of_device_id ina3221_of_match_table[] = {
422	{ .compatible = "ti,ina3221", },
423	{ /* sentinel */ }
424	};
425	MODULE_DEVICE_TABLE(of, ina3221_of_match_table);
426
427	static const struct i2c_device_id ina3221_ids[] = {
428	{ "ina3221", 0 },
429	{ /* sentinel */ }
430	};
431	MODULE_DEVICE_TABLE(i2c, ina3221_ids);
432
433	static struct i2c_driver ina3221_i2c_driver = {
434	.probe = ina3221_probe,
435	.driver = {
436	.name = INA3221_DRIVER_NAME,
437	.of_match_table = ina3221_of_match_table,
438	},
439	.id_table = ina3221_ids,
440	};
441	module_i2c_driver(ina3221_i2c_driver);
442
443	MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
444	MODULE_DESCRIPTION("Texas Instruments INA3221 HWMon Driver");
445	MODULE_LICENSE("GPL v2");