[linux.git] / drivers / hwmon / ina2xx.c

/*
 * Driver for Texas Instruments INA219, INA226 power monitor chips
 *
 * INA219:
 * Zero Drift Bi-Directional Current/Power Monitor with I2C Interface
 * Datasheet: http://www.ti.com/product/ina219
 *
 * INA220:
 * Bi-Directional Current/Power Monitor with I2C Interface
 * Datasheet: http://www.ti.com/product/ina220
 *
 * INA226:
 * Bi-Directional Current/Power Monitor with I2C Interface
 * Datasheet: http://www.ti.com/product/ina226
 *
 * INA230:
 * Bi-directional Current/Power Monitor with I2C Interface
 * Datasheet: http://www.ti.com/product/ina230
 *
 * Copyright (C) 2012 Lothar Felten <[email protected]>
 * Thanks to Jan Volkering
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/jiffies.h>

#include <linux/platform_data/ina2xx.h>

/* common register definitions */
#define INA2XX_CONFIG			0x00
#define INA2XX_SHUNT_VOLTAGE		0x01 /* readonly */
#define INA2XX_BUS_VOLTAGE		0x02 /* readonly */
#define INA2XX_POWER			0x03 /* readonly */
#define INA2XX_CURRENT			0x04 /* readonly */
#define INA2XX_CALIBRATION		0x05

/* INA226 register definitions */
#define INA226_MASK_ENABLE		0x06
#define INA226_ALERT_LIMIT		0x07
#define INA226_DIE_ID			0xFF


/* register count */
#define INA219_REGISTERS		6
#define INA226_REGISTERS		8

#define INA2XX_MAX_REGISTERS		8

/* settings - depend on use case */
#define INA219_CONFIG_DEFAULT		0x399F	/* PGA=8 */
#define INA226_CONFIG_DEFAULT		0x4527	/* averages=16 */

/* worst case is 68.10 ms (~14.6Hz, ina219) */
#define INA2XX_CONVERSION_RATE		15

enum ina2xx_ids { ina219, ina226 };

struct ina2xx_config {
	u16 config_default;
	int calibration_factor;
	int registers;
	int shunt_div;
	int bus_voltage_shift;
	int bus_voltage_lsb;	/* uV */
	int power_lsb;		/* uW */
};

struct ina2xx_data {
	struct device *hwmon_dev;
	const struct ina2xx_config *config;

	struct mutex update_lock;
	bool valid;
	unsigned long last_updated;

	int kind;
	u16 regs[INA2XX_MAX_REGISTERS];
};

static const struct ina2xx_config ina2xx_config[] = {
	[ina219] = {
		.config_default = INA219_CONFIG_DEFAULT,
		.calibration_factor = 40960000,
		.registers = INA219_REGISTERS,
		.shunt_div = 100,
		.bus_voltage_shift = 3,
		.bus_voltage_lsb = 4000,
		.power_lsb = 20000,
	},
	[ina226] = {
		.config_default = INA226_CONFIG_DEFAULT,
		.calibration_factor = 5120000,
		.registers = INA226_REGISTERS,
		.shunt_div = 400,
		.bus_voltage_shift = 0,
		.bus_voltage_lsb = 1250,
		.power_lsb = 25000,
	},
};

static struct ina2xx_data *ina2xx_update_device(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct ina2xx_data *data = i2c_get_clientdata(client);
	struct ina2xx_data *ret = data;

	mutex_lock(&data->update_lock);

	if (time_after(jiffies, data->last_updated +
		       HZ / INA2XX_CONVERSION_RATE) || !data->valid) {

		int i;

		dev_dbg(&client->dev, "Starting ina2xx update\n");

		/* Read all registers */
		for (i = 0; i < data->config->registers; i++) {
			int rv = i2c_smbus_read_word_swapped(client, i);
			if (rv < 0) {
				ret = ERR_PTR(rv);
				goto abort;
			}
			data->regs[i] = rv;
		}
		data->last_updated = jiffies;
		data->valid = 1;
	}
abort:
	mutex_unlock(&data->update_lock);
	return ret;
}

static int ina2xx_get_value(struct ina2xx_data *data, u8 reg)
{
	int val;

	switch (reg) {
	case INA2XX_SHUNT_VOLTAGE:
		val = DIV_ROUND_CLOSEST(data->regs[reg],
					data->config->shunt_div);
		break;
	case INA2XX_BUS_VOLTAGE:
		val = (data->regs[reg] >> data->config->bus_voltage_shift)
		  * data->config->bus_voltage_lsb;
		val = DIV_ROUND_CLOSEST(val, 1000);
		break;
	case INA2XX_POWER:
		val = data->regs[reg] * data->config->power_lsb;
		break;
	case INA2XX_CURRENT:
		/* LSB=1mA (selected). Is in mA */
		val = data->regs[reg];
		break;
	default:
		/* programmer goofed */
		WARN_ON_ONCE(1);
		val = 0;
		break;
	}

	return val;
}

static ssize_t ina2xx_show_value(struct device *dev,
				 struct device_attribute *da, char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	struct ina2xx_data *data = ina2xx_update_device(dev);

	if (IS_ERR(data))
		return PTR_ERR(data);

	return snprintf(buf, PAGE_SIZE, "%d\n",
			ina2xx_get_value(data, attr->index));
}

/* shunt voltage */
static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, \
	ina2xx_show_value, NULL, INA2XX_SHUNT_VOLTAGE);

/* bus voltage */
static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, \
	ina2xx_show_value, NULL, INA2XX_BUS_VOLTAGE);

/* calculated current */
static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, \
	ina2xx_show_value, NULL, INA2XX_CURRENT);

/* calculated power */
static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, \
	ina2xx_show_value, NULL, INA2XX_POWER);

/* pointers to created device attributes */
static struct attribute *ina2xx_attributes[] = {
	&sensor_dev_attr_in0_input.dev_attr.attr,
	&sensor_dev_attr_in1_input.dev_attr.attr,
	&sensor_dev_attr_curr1_input.dev_attr.attr,
	&sensor_dev_attr_power1_input.dev_attr.attr,
	NULL,
};

static const struct attribute_group ina2xx_group = {
	.attrs = ina2xx_attributes,
};

static int ina2xx_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct i2c_adapter *adapter = client->adapter;
	struct ina2xx_data *data;
	struct ina2xx_platform_data *pdata;
	int ret;
	long shunt = 10000; /* default shunt value 10mOhms */

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
		return -ENODEV;

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

	if (client->dev.platform_data) {
		pdata =
		  (struct ina2xx_platform_data *)client->dev.platform_data;
		shunt = pdata->shunt_uohms;
	}

	if (shunt <= 0)
		return -ENODEV;

	/* set the device type */
	data->kind = id->driver_data;
	data->config = &ina2xx_config[data->kind];

	/* device configuration */
	i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
				     data->config->config_default);
	/* set current LSB to 1mA, shunt is in uOhms */
	/* (equation 13 in datasheet) */
	i2c_smbus_write_word_swapped(client, INA2XX_CALIBRATION,
				     data->config->calibration_factor / shunt);

	i2c_set_clientdata(client, data);
	mutex_init(&data->update_lock);

	ret = sysfs_create_group(&client->dev.kobj, &ina2xx_group);
	if (ret)
		return ret;

	data->hwmon_dev = hwmon_device_register(&client->dev);
	if (IS_ERR(data->hwmon_dev)) {
		ret = PTR_ERR(data->hwmon_dev);
		goto out_err_hwmon;
	}

	dev_info(&client->dev, "power monitor %s (Rshunt = %li uOhm)\n",
		 id->name, shunt);

	return 0;

out_err_hwmon:
	sysfs_remove_group(&client->dev.kobj, &ina2xx_group);
	return ret;
}

static int ina2xx_remove(struct i2c_client *client)
{
	struct ina2xx_data *data = i2c_get_clientdata(client);

	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&client->dev.kobj, &ina2xx_group);

	return 0;
}

static const struct i2c_device_id ina2xx_id[] = {
	{ "ina219", ina219 },
	{ "ina220", ina219 },
	{ "ina226", ina226 },
	{ "ina230", ina226 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, ina2xx_id);

static struct i2c_driver ina2xx_driver = {
	.driver = {
		.name	= "ina2xx",
	},
	.probe		= ina2xx_probe,
	.remove		= ina2xx_remove,
	.id_table	= ina2xx_id,
};

module_i2c_driver(ina2xx_driver);

MODULE_AUTHOR("Lothar Felten <[email protected]>");
MODULE_DESCRIPTION("ina2xx driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
f7c2fe38 FL	1	/*
	2	* Driver for Texas Instruments INA219, INA226 power monitor chips
	3	*
	4	* INA219:
	5	* Zero Drift Bi-Directional Current/Power Monitor with I2C Interface
	6	* Datasheet: http://www.ti.com/product/ina219
	7	*
dc92cd0c GR	8	* INA220:
	9	* Bi-Directional Current/Power Monitor with I2C Interface
	10	* Datasheet: http://www.ti.com/product/ina220
	11	*
f7c2fe38 FL	12	* INA226:
	13	* Bi-Directional Current/Power Monitor with I2C Interface
	14	* Datasheet: http://www.ti.com/product/ina226
	15	*
dc92cd0c GR	16	* INA230:
	17	* Bi-directional Current/Power Monitor with I2C Interface
	18	* Datasheet: http://www.ti.com/product/ina230
	19	*
f7c2fe38 FL	20	* Copyright (C) 2012 Lothar Felten <[email protected]>
	21	* Thanks to Jan Volkering
	22	*
	23	* This program is free software; you can redistribute it and/or modify
	24	* it under the terms of the GNU General Public License as published by
	25	* the Free Software Foundation; version 2 of the License.
	26	*/
	27
	28	#include <linux/kernel.h>
	29	#include <linux/module.h>
	30	#include <linux/init.h>
	31	#include <linux/err.h>
	32	#include <linux/slab.h>
	33	#include <linux/i2c.h>
	34	#include <linux/hwmon.h>
	35	#include <linux/hwmon-sysfs.h>
dcd8f392	36	#include <linux/jiffies.h>
f7c2fe38 FL	37
	38	#include <linux/platform_data/ina2xx.h>
	39
	40	/* common register definitions */
	41	#define INA2XX_CONFIG 0x00
	42	#define INA2XX_SHUNT_VOLTAGE 0x01 /* readonly */
	43	#define INA2XX_BUS_VOLTAGE 0x02 /* readonly */
	44	#define INA2XX_POWER 0x03 /* readonly */
	45	#define INA2XX_CURRENT 0x04 /* readonly */
	46	#define INA2XX_CALIBRATION 0x05
	47
	48	/* INA226 register definitions */
	49	#define INA226_MASK_ENABLE 0x06
	50	#define INA226_ALERT_LIMIT 0x07
	51	#define INA226_DIE_ID 0xFF
	52
	53
	54	/* register count */
	55	#define INA219_REGISTERS 6
	56	#define INA226_REGISTERS 8
	57
	58	#define INA2XX_MAX_REGISTERS 8
	59
	60	/* settings - depend on use case */
	61	#define INA219_CONFIG_DEFAULT 0x399F /* PGA=8 */
	62	#define INA226_CONFIG_DEFAULT 0x4527 /* averages=16 */
	63
	64	/* worst case is 68.10 ms (~14.6Hz, ina219) */
	65	#define INA2XX_CONVERSION_RATE 15
	66
	67	enum ina2xx_ids { ina219, ina226 };
	68
6106db25 GR	69	struct ina2xx_config {
	70	u16 config_default;
	71	int calibration_factor;
	72	int registers;
	73	int shunt_div;
	74	int bus_voltage_shift;
	75	int bus_voltage_lsb; /* uV */
	76	int power_lsb; /* uW */
	77	};
	78
f7c2fe38 FL	79	struct ina2xx_data {
f7c2fe38 FL	80	struct device *hwmon_dev;
6106db25	81	const struct ina2xx_config *config;
f7c2fe38 FL	82
	83	struct mutex update_lock;
	84	bool valid;
	85	unsigned long last_updated;
	86
	87	int kind;
f7c2fe38 FL	88	u16 regs[INA2XX_MAX_REGISTERS];
	89	};
	90
6106db25 GR	91	static const struct ina2xx_config ina2xx_config[] = {
	92	[ina219] = {
	93	.config_default = INA219_CONFIG_DEFAULT,
	94	.calibration_factor = 40960000,
	95	.registers = INA219_REGISTERS,
	96	.shunt_div = 100,
	97	.bus_voltage_shift = 3,
	98	.bus_voltage_lsb = 4000,
	99	.power_lsb = 20000,
	100	},
	101	[ina226] = {
	102	.config_default = INA226_CONFIG_DEFAULT,
	103	.calibration_factor = 5120000,
	104	.registers = INA226_REGISTERS,
	105	.shunt_div = 400,
	106	.bus_voltage_shift = 0,
	107	.bus_voltage_lsb = 1250,
	108	.power_lsb = 25000,
	109	},
	110	};
	111
f7c2fe38 FL	112	static struct ina2xx_data ina2xx_update_device(struct device dev)
	113	{
	114	struct i2c_client *client = to_i2c_client(dev);
	115	struct ina2xx_data *data = i2c_get_clientdata(client);
	116	struct ina2xx_data *ret = data;
	117
	118	mutex_lock(&data->update_lock);
	119
	120	if (time_after(jiffies, data->last_updated +
	121	HZ / INA2XX_CONVERSION_RATE) \|\| !data->valid) {
	122
	123	int i;
	124
	125	dev_dbg(&client->dev, "Starting ina2xx update\n");
	126
	127	/* Read all registers */
6106db25	128	for (i = 0; i < data->config->registers; i++) {
080b98e9	129	int rv = i2c_smbus_read_word_swapped(client, i);
f7c2fe38 FL	130	if (rv < 0) {
	131	ret = ERR_PTR(rv);
	132	goto abort;
	133	}
	134	data->regs[i] = rv;
	135	}
	136	data->last_updated = jiffies;
	137	data->valid = 1;
	138	}
	139	abort:
	140	mutex_unlock(&data->update_lock);
	141	return ret;
	142	}
	143
6106db25	144	static int ina2xx_get_value(struct ina2xx_data *data, u8 reg)
f7c2fe38	145	{
6106db25	146	int val;
f7c2fe38 FL	147
	148	switch (reg) {
	149	case INA2XX_SHUNT_VOLTAGE:
6106db25 GR	150	val = DIV_ROUND_CLOSEST(data->regs[reg],
6106db25 GR	151	data->config->shunt_div);
f7c2fe38 FL	152	break;
f7c2fe38 FL	153	case INA2XX_BUS_VOLTAGE:
6106db25 GR	154	val = (data->regs[reg] >> data->config->bus_voltage_shift)
	155	* data->config->bus_voltage_lsb;
	156	val = DIV_ROUND_CLOSEST(val, 1000);
f7c2fe38 FL	157	break;
f7c2fe38 FL	158	case INA2XX_POWER:
6106db25	159	val = data->regs[reg] * data->config->power_lsb;
f7c2fe38 FL	160	break;
	161	case INA2XX_CURRENT:
	162	/* LSB=1mA (selected). Is in mA */
6106db25	163	val = data->regs[reg];
f7c2fe38 FL	164	break;
	165	default:
	166	/* programmer goofed */
	167	WARN_ON_ONCE(1);
	168	val = 0;
	169	break;
	170	}
	171
	172	return val;
	173	}
	174
	175	static ssize_t ina2xx_show_value(struct device *dev,
	176	struct device_attribute da, char buf)
	177	{
	178	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	179	struct ina2xx_data *data = ina2xx_update_device(dev);
f7c2fe38 FL	180
	181	if (IS_ERR(data))
	182	return PTR_ERR(data);
	183
6106db25 GR	184	return snprintf(buf, PAGE_SIZE, "%d\n",
6106db25 GR	185	ina2xx_get_value(data, attr->index));
f7c2fe38 FL	186	}
	187
	188	/* shunt voltage */
	189	static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, \
	190	ina2xx_show_value, NULL, INA2XX_SHUNT_VOLTAGE);
	191
	192	/* bus voltage */
	193	static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, \
	194	ina2xx_show_value, NULL, INA2XX_BUS_VOLTAGE);
	195
	196	/* calculated current */
	197	static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, \
	198	ina2xx_show_value, NULL, INA2XX_CURRENT);
	199
	200	/* calculated power */
	201	static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, \
	202	ina2xx_show_value, NULL, INA2XX_POWER);
	203
	204	/* pointers to created device attributes */
	205	static struct attribute *ina2xx_attributes[] = {
	206	&sensor_dev_attr_in0_input.dev_attr.attr,
	207	&sensor_dev_attr_in1_input.dev_attr.attr,
	208	&sensor_dev_attr_curr1_input.dev_attr.attr,
	209	&sensor_dev_attr_power1_input.dev_attr.attr,
	210	NULL,
	211	};
	212
	213	static const struct attribute_group ina2xx_group = {
	214	.attrs = ina2xx_attributes,
	215	};
	216
	217	static int ina2xx_probe(struct i2c_client *client,
	218	const struct i2c_device_id *id)
	219	{
	220	struct i2c_adapter *adapter = client->adapter;
	221	struct ina2xx_data *data;
	222	struct ina2xx_platform_data *pdata;
6106db25	223	int ret;
f7c2fe38 FL	224	long shunt = 10000; /* default shunt value 10mOhms */
	225
	226	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
	227	return -ENODEV;
	228
	229	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
	230	if (!data)
	231	return -ENOMEM;
	232
	233	if (client->dev.platform_data) {
	234	pdata =
	235	(struct ina2xx_platform_data *)client->dev.platform_data;
	236	shunt = pdata->shunt_uohms;
	237	}
	238
	239	if (shunt <= 0)
	240	return -ENODEV;
	241
	242	/* set the device type */
	243	data->kind = id->driver_data;
6106db25	244	data->config = &ina2xx_config[data->kind];
f7c2fe38	245
6106db25 GR	246	/* device configuration */
	247	i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
	248	data->config->config_default);
	249	/* set current LSB to 1mA, shunt is in uOhms */
	250	/* (equation 13 in datasheet) */
	251	i2c_smbus_write_word_swapped(client, INA2XX_CALIBRATION,
	252	data->config->calibration_factor / shunt);
f7c2fe38 FL	253
	254	i2c_set_clientdata(client, data);
	255	mutex_init(&data->update_lock);
	256
	257	ret = sysfs_create_group(&client->dev.kobj, &ina2xx_group);
	258	if (ret)
	259	return ret;
	260
	261	data->hwmon_dev = hwmon_device_register(&client->dev);
	262	if (IS_ERR(data->hwmon_dev)) {
	263	ret = PTR_ERR(data->hwmon_dev);
	264	goto out_err_hwmon;
	265	}
	266
6106db25 GR	267	dev_info(&client->dev, "power monitor %s (Rshunt = %li uOhm)\n",
	268	id->name, shunt);
	269
f7c2fe38 FL	270	return 0;
	271
	272	out_err_hwmon:
	273	sysfs_remove_group(&client->dev.kobj, &ina2xx_group);
	274	return ret;
	275	}
	276
	277	static int ina2xx_remove(struct i2c_client *client)
	278	{
	279	struct ina2xx_data *data = i2c_get_clientdata(client);
	280
	281	hwmon_device_unregister(data->hwmon_dev);
	282	sysfs_remove_group(&client->dev.kobj, &ina2xx_group);
	283
	284	return 0;
	285	}
	286
	287	static const struct i2c_device_id ina2xx_id[] = {
	288	{ "ina219", ina219 },
dc92cd0c	289	{ "ina220", ina219 },
f7c2fe38	290	{ "ina226", ina226 },
dc92cd0c	291	{ "ina230", ina226 },
f7c2fe38 FL	292	{ }
	293	};
	294	MODULE_DEVICE_TABLE(i2c, ina2xx_id);
	295
	296	static struct i2c_driver ina2xx_driver = {
	297	.driver = {
	298	.name = "ina2xx",
	299	},
	300	.probe = ina2xx_probe,
	301	.remove = ina2xx_remove,
	302	.id_table = ina2xx_id,
	303	};
	304
d835ca0f	305	module_i2c_driver(ina2xx_driver);
f7c2fe38 FL	306
	307	MODULE_AUTHOR("Lothar Felten <[email protected]>");
	308	MODULE_DESCRIPTION("ina2xx driver");
	309	MODULE_LICENSE("GPL");