[deliverable/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 <l-felten@ti.com>
 * 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/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,
};

static int __init ina2xx_init(void)
{
	return i2c_add_driver(&ina2xx_driver);
}

static void __exit ina2xx_exit(void)
{
	i2c_del_driver(&ina2xx_driver);
}

MODULE_AUTHOR("Lothar Felten <l-felten@ti.com>");
MODULE_DESCRIPTION("ina2xx driver");
MODULE_LICENSE("GPL");

module_init(ina2xx_init);
module_exit(ina2xx_exit);
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 <l-felten@ti.com>
	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>
	36
	37	#include <linux/platform_data/ina2xx.h>
	38
	39	/* common register definitions */
	40	#define INA2XX_CONFIG 0x00
	41	#define INA2XX_SHUNT_VOLTAGE 0x01 /* readonly */
	42	#define INA2XX_BUS_VOLTAGE 0x02 /* readonly */
	43	#define INA2XX_POWER 0x03 /* readonly */
	44	#define INA2XX_CURRENT 0x04 /* readonly */
	45	#define INA2XX_CALIBRATION 0x05
	46
	47	/* INA226 register definitions */
	48	#define INA226_MASK_ENABLE 0x06
	49	#define INA226_ALERT_LIMIT 0x07
	50	#define INA226_DIE_ID 0xFF
	51
	52
	53	/* register count */
	54	#define INA219_REGISTERS 6
	55	#define INA226_REGISTERS 8
	56
	57	#define INA2XX_MAX_REGISTERS 8
	58
	59	/* settings - depend on use case */
	60	#define INA219_CONFIG_DEFAULT 0x399F /* PGA=8 */
	61	#define INA226_CONFIG_DEFAULT 0x4527 /* averages=16 */
	62
	63	/* worst case is 68.10 ms (~14.6Hz, ina219) */
	64	#define INA2XX_CONVERSION_RATE 15
	65
	66	enum ina2xx_ids { ina219, ina226 };
	67
6106db25 GR	68	struct ina2xx_config {
	69	u16 config_default;
	70	int calibration_factor;
	71	int registers;
	72	int shunt_div;
	73	int bus_voltage_shift;
	74	int bus_voltage_lsb; /* uV */
	75	int power_lsb; /* uW */
	76	};
	77
f7c2fe38 FL	78	struct ina2xx_data {
f7c2fe38 FL	79	struct device *hwmon_dev;
6106db25	80	const struct ina2xx_config *config;
f7c2fe38 FL	81
	82	struct mutex update_lock;
	83	bool valid;
	84	unsigned long last_updated;
	85
	86	int kind;
f7c2fe38 FL	87	u16 regs[INA2XX_MAX_REGISTERS];
	88	};
	89
6106db25 GR	90	static const struct ina2xx_config ina2xx_config[] = {
	91	[ina219] = {
	92	.config_default = INA219_CONFIG_DEFAULT,
	93	.calibration_factor = 40960000,
	94	.registers = INA219_REGISTERS,
	95	.shunt_div = 100,
	96	.bus_voltage_shift = 3,
	97	.bus_voltage_lsb = 4000,
	98	.power_lsb = 20000,
	99	},
	100	[ina226] = {
	101	.config_default = INA226_CONFIG_DEFAULT,
	102	.calibration_factor = 5120000,
	103	.registers = INA226_REGISTERS,
	104	.shunt_div = 400,
	105	.bus_voltage_shift = 0,
	106	.bus_voltage_lsb = 1250,
	107	.power_lsb = 25000,
	108	},
	109	};
	110
f7c2fe38 FL	111	static struct ina2xx_data ina2xx_update_device(struct device dev)
	112	{
	113	struct i2c_client *client = to_i2c_client(dev);
	114	struct ina2xx_data *data = i2c_get_clientdata(client);
	115	struct ina2xx_data *ret = data;
	116
	117	mutex_lock(&data->update_lock);
	118
	119	if (time_after(jiffies, data->last_updated +
	120	HZ / INA2XX_CONVERSION_RATE) \|\| !data->valid) {
	121
	122	int i;
	123
	124	dev_dbg(&client->dev, "Starting ina2xx update\n");
	125
	126	/* Read all registers */
6106db25	127	for (i = 0; i < data->config->registers; i++) {
080b98e9	128	int rv = i2c_smbus_read_word_swapped(client, i);
f7c2fe38 FL	129	if (rv < 0) {
	130	ret = ERR_PTR(rv);
	131	goto abort;
	132	}
	133	data->regs[i] = rv;
	134	}
	135	data->last_updated = jiffies;
	136	data->valid = 1;
	137	}
	138	abort:
	139	mutex_unlock(&data->update_lock);
	140	return ret;
	141	}
	142
6106db25	143	static int ina2xx_get_value(struct ina2xx_data *data, u8 reg)
f7c2fe38	144	{
6106db25	145	int val;
f7c2fe38 FL	146
	147	switch (reg) {
	148	case INA2XX_SHUNT_VOLTAGE:
6106db25 GR	149	val = DIV_ROUND_CLOSEST(data->regs[reg],
6106db25 GR	150	data->config->shunt_div);
f7c2fe38 FL	151	break;
f7c2fe38 FL	152	case INA2XX_BUS_VOLTAGE:
6106db25 GR	153	val = (data->regs[reg] >> data->config->bus_voltage_shift)
	154	* data->config->bus_voltage_lsb;
	155	val = DIV_ROUND_CLOSEST(val, 1000);
f7c2fe38 FL	156	break;
f7c2fe38 FL	157	case INA2XX_POWER:
6106db25	158	val = data->regs[reg] * data->config->power_lsb;
f7c2fe38 FL	159	break;
	160	case INA2XX_CURRENT:
	161	/* LSB=1mA (selected). Is in mA */
6106db25	162	val = data->regs[reg];
f7c2fe38 FL	163	break;
	164	default:
	165	/* programmer goofed */
	166	WARN_ON_ONCE(1);
	167	val = 0;
	168	break;
	169	}
	170
	171	return val;
	172	}
	173
	174	static ssize_t ina2xx_show_value(struct device *dev,
	175	struct device_attribute da, char buf)
	176	{
	177	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	178	struct ina2xx_data *data = ina2xx_update_device(dev);
f7c2fe38 FL	179
	180	if (IS_ERR(data))
	181	return PTR_ERR(data);
	182
6106db25 GR	183	return snprintf(buf, PAGE_SIZE, "%d\n",
6106db25 GR	184	ina2xx_get_value(data, attr->index));
f7c2fe38 FL	185	}
	186
	187	/* shunt voltage */
	188	static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, \
	189	ina2xx_show_value, NULL, INA2XX_SHUNT_VOLTAGE);
	190
	191	/* bus voltage */
	192	static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, \
	193	ina2xx_show_value, NULL, INA2XX_BUS_VOLTAGE);
	194
	195	/* calculated current */
	196	static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, \
	197	ina2xx_show_value, NULL, INA2XX_CURRENT);
	198
	199	/* calculated power */
	200	static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, \
	201	ina2xx_show_value, NULL, INA2XX_POWER);
	202
	203	/* pointers to created device attributes */
	204	static struct attribute *ina2xx_attributes[] = {
	205	&sensor_dev_attr_in0_input.dev_attr.attr,
	206	&sensor_dev_attr_in1_input.dev_attr.attr,
	207	&sensor_dev_attr_curr1_input.dev_attr.attr,
	208	&sensor_dev_attr_power1_input.dev_attr.attr,
	209	NULL,
	210	};
	211
	212	static const struct attribute_group ina2xx_group = {
	213	.attrs = ina2xx_attributes,
	214	};
	215
	216	static int ina2xx_probe(struct i2c_client *client,
	217	const struct i2c_device_id *id)
	218	{
	219	struct i2c_adapter *adapter = client->adapter;
	220	struct ina2xx_data *data;
	221	struct ina2xx_platform_data *pdata;
6106db25	222	int ret;
f7c2fe38 FL	223	long shunt = 10000; /* default shunt value 10mOhms */
	224
	225	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
	226	return -ENODEV;
	227
	228	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
	229	if (!data)
	230	return -ENOMEM;
	231
	232	if (client->dev.platform_data) {
	233	pdata =
	234	(struct ina2xx_platform_data *)client->dev.platform_data;
	235	shunt = pdata->shunt_uohms;
	236	}
	237
	238	if (shunt <= 0)
	239	return -ENODEV;
	240
	241	/* set the device type */
	242	data->kind = id->driver_data;
6106db25	243	data->config = &ina2xx_config[data->kind];
f7c2fe38	244
6106db25 GR	245	/* device configuration */
	246	i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
	247	data->config->config_default);
	248	/* set current LSB to 1mA, shunt is in uOhms */
	249	/* (equation 13 in datasheet) */
	250	i2c_smbus_write_word_swapped(client, INA2XX_CALIBRATION,
	251	data->config->calibration_factor / shunt);
f7c2fe38 FL	252
	253	i2c_set_clientdata(client, data);
	254	mutex_init(&data->update_lock);
	255
	256	ret = sysfs_create_group(&client->dev.kobj, &ina2xx_group);
	257	if (ret)
	258	return ret;
	259
	260	data->hwmon_dev = hwmon_device_register(&client->dev);
	261	if (IS_ERR(data->hwmon_dev)) {
	262	ret = PTR_ERR(data->hwmon_dev);
	263	goto out_err_hwmon;
	264	}
	265
6106db25 GR	266	dev_info(&client->dev, "power monitor %s (Rshunt = %li uOhm)\n",
	267	id->name, shunt);
	268
f7c2fe38 FL	269	return 0;
	270
	271	out_err_hwmon:
	272	sysfs_remove_group(&client->dev.kobj, &ina2xx_group);
	273	return ret;
	274	}
	275
	276	static int ina2xx_remove(struct i2c_client *client)
	277	{
	278	struct ina2xx_data *data = i2c_get_clientdata(client);
	279
	280	hwmon_device_unregister(data->hwmon_dev);
	281	sysfs_remove_group(&client->dev.kobj, &ina2xx_group);
	282
	283	return 0;
	284	}
	285
	286	static const struct i2c_device_id ina2xx_id[] = {
	287	{ "ina219", ina219 },
dc92cd0c	288	{ "ina220", ina219 },
f7c2fe38	289	{ "ina226", ina226 },
dc92cd0c	290	{ "ina230", ina226 },
f7c2fe38 FL	291	{ }
	292	};
	293	MODULE_DEVICE_TABLE(i2c, ina2xx_id);
	294
	295	static struct i2c_driver ina2xx_driver = {
	296	.driver = {
	297	.name = "ina2xx",
	298	},
	299	.probe = ina2xx_probe,
	300	.remove = ina2xx_remove,
	301	.id_table = ina2xx_id,
	302	};
	303
	304	static int __init ina2xx_init(void)
	305	{
	306	return i2c_add_driver(&ina2xx_driver);
	307	}
	308
	309	static void __exit ina2xx_exit(void)
	310	{
	311	i2c_del_driver(&ina2xx_driver);
	312	}
	313
	314	MODULE_AUTHOR("Lothar Felten <l-felten@ti.com>");
	315	MODULE_DESCRIPTION("ina2xx driver");
	316	MODULE_LICENSE("GPL");
	317
	318	module_init(ina2xx_init);
	319	module_exit(ina2xx_exit);