drivers/iio/temperature/tmp007.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * tmp007.c - Support for TI TMP007 IR thermopile sensor with integrated math engine
  *
  * Copyright (c) 2017 Manivannan Sadhasivam <manivannanece23@gmail.com>
  *
  * Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
  *
  * (7-bit I2C slave address (0x40 - 0x47), changeable via ADR pins)
  *
  * Note:
  * 1. This driver assumes that the sensor has been calibrated beforehand
  * 2. Limit threshold events are enabled at the start
  * 3. Operating mode: INT
  */

 #include <linux/err.h>
 #include <linux/i2c.h>
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/pm.h>
 #include <linux/bitops.h>
 #include <linux/of.h>
 #include <linux/irq.h>
 #include <linux/interrupt.h>

 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
 #include <linux/iio/events.h>

 #define TMP007_TDIE 0x01
 #define TMP007_CONFIG 0x02
 #define TMP007_TOBJECT 0x03
 #define TMP007_STATUS 0x04
 #define TMP007_STATUS_MASK 0x05
 #define TMP007_TOBJ_HIGH_LIMIT 0x06
 #define TMP007_TOBJ_LOW_LIMIT 0x07
 #define TMP007_TDIE_HIGH_LIMIT 0x08
 #define TMP007_TDIE_LOW_LIMIT 0x09
 #define TMP007_MANUFACTURER_ID 0x1e
 #define TMP007_DEVICE_ID 0x1f

 #define TMP007_CONFIG_CONV_EN BIT(12)
 #define TMP007_CONFIG_TC_EN BIT(6)
 #define TMP007_CONFIG_CR_MASK GENMASK(11, 9)
 #define TMP007_CONFIG_ALERT_EN BIT(8)
 #define TMP007_CONFIG_CR_SHIFT 9

 /* Status register flags */
 #define TMP007_STATUS_ALERT BIT(15)
 #define TMP007_STATUS_CONV_READY BIT(14)
 #define TMP007_STATUS_OHF BIT(13)
 #define TMP007_STATUS_OLF BIT(12)
 #define TMP007_STATUS_LHF BIT(11)
 #define TMP007_STATUS_LLF BIT(10)
 #define TMP007_STATUS_DATA_VALID BIT(9)

 #define TMP007_MANUFACTURER_MAGIC 0x5449
 #define TMP007_DEVICE_MAGIC 0x0078

 #define TMP007_TEMP_SHIFT 2

 struct tmp007_data {
 	struct i2c_client *client;
 	struct mutex lock;
 	u16 config;
 	u16 status_mask;
 };

 static const int tmp007_avgs[5][2] = { {4, 0}, {2, 0}, {1, 0},
 					{0, 500000}, {0, 250000} };

 static int tmp007_read_temperature(struct tmp007_data *data, u8 reg)
 {
 	s32 ret;
 	int tries = 50;

 	while (tries-- > 0) {
 		ret = i2c_smbus_read_word_swapped(data->client,
 			TMP007_STATUS);
 		if (ret < 0)
 			return ret;
 		if ((ret & TMP007_STATUS_CONV_READY) &&
 			!(ret & TMP007_STATUS_DATA_VALID))
 				break;
 		msleep(100);
 	}

 	if (tries < 0)
 		return -EIO;

 	return i2c_smbus_read_word_swapped(data->client, reg);
 }

 static int tmp007_powerdown(struct tmp007_data *data)
 {
 	return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
 			data->config & ~TMP007_CONFIG_CONV_EN);
 }

 static int tmp007_read_raw(struct iio_dev *indio_dev,
 		struct iio_chan_spec const *channel, int *val,
 		int *val2, long mask)
 {
 	struct tmp007_data *data = iio_priv(indio_dev);
 	s32 ret;
 	int conv_rate;

 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
 		switch (channel->channel2) {
 		case IIO_MOD_TEMP_AMBIENT: /* LSB: 0.03125 degree Celsius */
 			ret = i2c_smbus_read_word_swapped(data->client, TMP007_TDIE);
 			if (ret < 0)
 				return ret;
 			break;
 		case IIO_MOD_TEMP_OBJECT:
 			ret = tmp007_read_temperature(data, TMP007_TOBJECT);
 			if (ret < 0)
 				return ret;
 			break;
 		default:
 			return -EINVAL;
 		}

 		*val = sign_extend32(ret, 15) >> TMP007_TEMP_SHIFT;

 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_SCALE:
 		*val = 31;
 		*val2 = 250000;

 		return IIO_VAL_INT_PLUS_MICRO;
 	case IIO_CHAN_INFO_SAMP_FREQ:
 		conv_rate = (data->config & TMP007_CONFIG_CR_MASK)
 				>> TMP007_CONFIG_CR_SHIFT;
 		*val = tmp007_avgs[conv_rate][0];
 		*val2 = tmp007_avgs[conv_rate][1];

 		return IIO_VAL_INT_PLUS_MICRO;
 	default:
 		return -EINVAL;
 	}
 }

 static int tmp007_write_raw(struct iio_dev *indio_dev,
 		struct iio_chan_spec const *channel, int val,
 		int val2, long mask)
 {
 	struct tmp007_data *data = iio_priv(indio_dev);
 	int i;
 	u16 tmp;

 	if (mask == IIO_CHAN_INFO_SAMP_FREQ) {
 		for (i = 0; i < ARRAY_SIZE(tmp007_avgs); i++) {
 			if ((val == tmp007_avgs[i][0]) &&
 			(val2 == tmp007_avgs[i][1])) {
 				tmp = data->config & ~TMP007_CONFIG_CR_MASK;
 				tmp |= (i << TMP007_CONFIG_CR_SHIFT);

 				return i2c_smbus_write_word_swapped(data->client,
 								TMP007_CONFIG,
 								data->config = tmp);
 			}
 		}
 	}

 	return -EINVAL;
 }

 static irqreturn_t tmp007_interrupt_handler(int irq, void *private)
 {
 	struct iio_dev *indio_dev = private;
 	struct tmp007_data *data = iio_priv(indio_dev);
 	int ret;

 	ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS);
 	if ((ret < 0) || !(ret & (TMP007_STATUS_OHF | TMP007_STATUS_OLF |
 				TMP007_STATUS_LHF | TMP007_STATUS_LLF)))
 		return IRQ_NONE;

 	if (ret & TMP007_STATUS_OHF)
 		iio_push_event(indio_dev,
 				IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
 					IIO_MOD_TEMP_OBJECT,
 					IIO_EV_TYPE_THRESH,
 					IIO_EV_DIR_RISING),
 				iio_get_time_ns(indio_dev));

 	if (ret & TMP007_STATUS_OLF)
 		iio_push_event(indio_dev,
 				IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
 					IIO_MOD_TEMP_OBJECT,
 					IIO_EV_TYPE_THRESH,
 					IIO_EV_DIR_FALLING),
 				iio_get_time_ns(indio_dev));

 	if (ret & TMP007_STATUS_LHF)
 		iio_push_event(indio_dev,
 				IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
 					IIO_MOD_TEMP_AMBIENT,
 					IIO_EV_TYPE_THRESH,
 					IIO_EV_DIR_RISING),
 				iio_get_time_ns(indio_dev));

 	if (ret & TMP007_STATUS_LLF)
 		iio_push_event(indio_dev,
 				IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
 					IIO_MOD_TEMP_AMBIENT,
 					IIO_EV_TYPE_THRESH,
 					IIO_EV_DIR_FALLING),
 				iio_get_time_ns(indio_dev));

 	return IRQ_HANDLED;
 }

 static int tmp007_write_event_config(struct iio_dev *indio_dev,
 		const struct iio_chan_spec *chan, enum iio_event_type type,
 		enum iio_event_direction dir, int state)
 {
 	struct tmp007_data *data = iio_priv(indio_dev);
 	unsigned int status_mask;
 	int ret;

 	switch (chan->channel2) {
 	case IIO_MOD_TEMP_AMBIENT:
 	if (dir == IIO_EV_DIR_RISING)
 			status_mask = TMP007_STATUS_LHF;
 		else
 			status_mask = TMP007_STATUS_LLF;
 		break;
 	case IIO_MOD_TEMP_OBJECT:
 		if (dir == IIO_EV_DIR_RISING)
 			status_mask = TMP007_STATUS_OHF;
 		else
 			status_mask = TMP007_STATUS_OLF;
 		break;
 	default:
 		return -EINVAL;
 	}

 	mutex_lock(&data->lock);
 	ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS_MASK);
 	mutex_unlock(&data->lock);
 	if (ret < 0)
 		return ret;

 	if (state)
 		ret |= status_mask;
 	else
 		ret &= ~status_mask;

 	return i2c_smbus_write_word_swapped(data->client, TMP007_STATUS_MASK,
 					data->status_mask = ret);
 }

 static int tmp007_read_event_config(struct iio_dev *indio_dev,
 		const struct iio_chan_spec *chan, enum iio_event_type type,
 		enum iio_event_direction dir)
 {
 	struct tmp007_data *data = iio_priv(indio_dev);
 	unsigned int mask;

 	switch (chan->channel2) {
 	case IIO_MOD_TEMP_AMBIENT:
 		if (dir == IIO_EV_DIR_RISING)
 			mask = TMP007_STATUS_LHF;
 		else
 			mask = TMP007_STATUS_LLF;
 		break;
 	case IIO_MOD_TEMP_OBJECT:
 		if (dir == IIO_EV_DIR_RISING)
 			mask = TMP007_STATUS_OHF;
 		else
 			mask = TMP007_STATUS_OLF;
 		break;
 	default:
 		return -EINVAL;
 	}

 	return !!(data->status_mask & mask);
 }

 static int tmp007_read_thresh(struct iio_dev *indio_dev,
 		const struct iio_chan_spec *chan, enum iio_event_type type,
 		enum iio_event_direction dir, enum iio_event_info info,
 		int *val, int *val2)
 {
 	struct tmp007_data *data = iio_priv(indio_dev);
 	int ret;
 	u8 reg;

 	switch (chan->channel2) {
 	case IIO_MOD_TEMP_AMBIENT: /* LSB: 0.5 degree Celsius */
 		if (dir == IIO_EV_DIR_RISING)
 			reg = TMP007_TDIE_HIGH_LIMIT;
 		else
 			reg = TMP007_TDIE_LOW_LIMIT;
 		break;
 	case IIO_MOD_TEMP_OBJECT:
 		if (dir == IIO_EV_DIR_RISING)
 			reg = TMP007_TOBJ_HIGH_LIMIT;
 	else
 			reg = TMP007_TOBJ_LOW_LIMIT;
 		break;
 	default:
 		return -EINVAL;
 	}

 	ret = i2c_smbus_read_word_swapped(data->client, reg);
 	if (ret < 0)
 		return ret;

 	/* Shift length 7 bits = 6(15:6) + 1(0.5 LSB) */
 	*val = sign_extend32(ret, 15) >> 7;

 	return IIO_VAL_INT;
 }

 static int tmp007_write_thresh(struct iio_dev *indio_dev,
 		const struct iio_chan_spec *chan, enum iio_event_type type,
 		enum iio_event_direction dir, enum iio_event_info info,
 		int val, int val2)
 {
 	struct tmp007_data *data = iio_priv(indio_dev);
 	u8 reg;

 	switch (chan->channel2) {
 	case IIO_MOD_TEMP_AMBIENT:
 		if (dir == IIO_EV_DIR_RISING)
 			reg = TMP007_TDIE_HIGH_LIMIT;
 		else
 			reg = TMP007_TDIE_LOW_LIMIT;
 		break;
 	case IIO_MOD_TEMP_OBJECT:
 		if (dir == IIO_EV_DIR_RISING)
 			reg = TMP007_TOBJ_HIGH_LIMIT;
 		else
 			reg = TMP007_TOBJ_LOW_LIMIT;
 		break;
 	default:
 		return -EINVAL;
 	}

 	/* Full scale threshold value is +/- 256 degree Celsius */
 	if (val < -256 || val > 255)
 		return -EINVAL;

 	/* Shift length 7 bits = 6(15:6) + 1(0.5 LSB) */
 	return i2c_smbus_write_word_swapped(data->client, reg, (val << 7));
 }

 static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");

 static struct attribute *tmp007_attributes[] = {
 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
 	NULL
 };

 static const struct attribute_group tmp007_attribute_group = {
 	.attrs = tmp007_attributes,
 };

 static const struct iio_event_spec tmp007_obj_event[] = {
 	{
 		.type = IIO_EV_TYPE_THRESH,
 		.dir = IIO_EV_DIR_RISING,
 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
 			BIT(IIO_EV_INFO_ENABLE),
 	},
 	{
 		.type = IIO_EV_TYPE_THRESH,
 		.dir = IIO_EV_DIR_FALLING,
 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
 			BIT(IIO_EV_INFO_ENABLE),
 	},
 };

 static const struct iio_event_spec tmp007_die_event[] = {
 	{
 		.type = IIO_EV_TYPE_THRESH,
 		.dir = IIO_EV_DIR_RISING,
 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
 			BIT(IIO_EV_INFO_ENABLE),
 	},
 	{
 		.type = IIO_EV_TYPE_THRESH,
 		.dir = IIO_EV_DIR_FALLING,
 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
 			BIT(IIO_EV_INFO_ENABLE),
 	},
 };

 static const struct iio_chan_spec tmp007_channels[] = {
 	{
 		.type = IIO_TEMP,
 		.modified = 1,
 		.channel2 = IIO_MOD_TEMP_AMBIENT,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 				BIT(IIO_CHAN_INFO_SCALE),
 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 		.event_spec = tmp007_die_event,
 		.num_event_specs = ARRAY_SIZE(tmp007_die_event),
 	},
 	{
 		.type = IIO_TEMP,
 		.modified = 1,
 		.channel2 = IIO_MOD_TEMP_OBJECT,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 				BIT(IIO_CHAN_INFO_SCALE),
 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 		.event_spec = tmp007_obj_event,
 		.num_event_specs = ARRAY_SIZE(tmp007_obj_event),
 	}
 };

 static const struct iio_info tmp007_info = {
 	.read_raw = tmp007_read_raw,
 	.write_raw = tmp007_write_raw,
 	.read_event_config = tmp007_read_event_config,
 	.write_event_config = tmp007_write_event_config,
 	.read_event_value = tmp007_read_thresh,
 	.write_event_value = tmp007_write_thresh,
 	.attrs = &tmp007_attribute_group,
 };

 static bool tmp007_identify(struct i2c_client *client)
 {
 	int manf_id, dev_id;

 	manf_id = i2c_smbus_read_word_swapped(client, TMP007_MANUFACTURER_ID);
 	if (manf_id < 0)
 		return false;

 	dev_id = i2c_smbus_read_word_swapped(client, TMP007_DEVICE_ID);
 	if (dev_id < 0)
 		return false;

 	return (manf_id == TMP007_MANUFACTURER_MAGIC && dev_id == TMP007_DEVICE_MAGIC);
 }

 static int tmp007_probe(struct i2c_client *client,
 			const struct i2c_device_id *tmp007_id)
 {
 	struct tmp007_data *data;
 	struct iio_dev *indio_dev;
 	int ret;

 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
 		return -EOPNOTSUPP;

 	if (!tmp007_identify(client)) {
 		dev_err(&client->dev, "TMP007 not found\n");
 		return -ENODEV;
 	}

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

 	data = iio_priv(indio_dev);
 	i2c_set_clientdata(client, indio_dev);
 	data->client = client;
 	mutex_init(&data->lock);

 	indio_dev->dev.parent = &client->dev;
 	indio_dev->name = "tmp007";
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &tmp007_info;

 	indio_dev->channels = tmp007_channels;
 	indio_dev->num_channels = ARRAY_SIZE(tmp007_channels);

 	/*
 	 * Set Configuration register:
 	 * 1. Conversion ON
 	 * 2. ALERT enable
 	 * 3. Transient correction enable
 	 */

 	ret = i2c_smbus_read_word_swapped(data->client, TMP007_CONFIG);
 	if (ret < 0)
 		return ret;

 	data->config = ret;
 	data->config |= (TMP007_CONFIG_CONV_EN | TMP007_CONFIG_ALERT_EN | TMP007_CONFIG_TC_EN);

 	ret = i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
 					data->config);
 	if (ret < 0)
 		return ret;

 	/*
 	 * Only the following flags can activate ALERT pin. Data conversion/validity flags
 	 * flags can still be polled for getting temperature data
 	 *
 	 * Set Status Mask register:
 	 * 1. Object temperature high limit enable
 	 * 2. Object temperature low limit enable
 	 * 3. TDIE temperature high limit enable
 	 * 4. TDIE temperature low limit enable
 	 */

 	ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS_MASK);
 	if (ret < 0)
 		goto error_powerdown;

 	data->status_mask = ret;
 	data->status_mask |= (TMP007_STATUS_OHF | TMP007_STATUS_OLF
 				| TMP007_STATUS_LHF | TMP007_STATUS_LLF);

 	ret = i2c_smbus_write_word_swapped(data->client, TMP007_STATUS_MASK, data->status_mask);
 	if (ret < 0)
 		goto error_powerdown;

 	if (client->irq) {
 		ret = devm_request_threaded_irq(&client->dev, client->irq,
 				NULL, tmp007_interrupt_handler,
 				IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 				tmp007_id->name, indio_dev);
 		if (ret) {
 			dev_err(&client->dev, "irq request error %d\n", -ret);
 			goto error_powerdown;
 		}
 	}

 	return iio_device_register(indio_dev);

 error_powerdown:
 	tmp007_powerdown(data);

 	return ret;
 }

 static int tmp007_remove(struct i2c_client *client)
 {
 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
 	struct tmp007_data *data = iio_priv(indio_dev);

 	iio_device_unregister(indio_dev);
 	tmp007_powerdown(data);

 	return 0;
 }

 #ifdef CONFIG_PM_SLEEP
 static int tmp007_suspend(struct device *dev)
 {
 	struct tmp007_data *data = iio_priv(i2c_get_clientdata(
 			to_i2c_client(dev)));

 	return tmp007_powerdown(data);
 }

 static int tmp007_resume(struct device *dev)
 {
 	struct tmp007_data *data = iio_priv(i2c_get_clientdata(
 			to_i2c_client(dev)));

 	return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
 			data->config | TMP007_CONFIG_CONV_EN);
 }
 #endif

 static SIMPLE_DEV_PM_OPS(tmp007_pm_ops, tmp007_suspend, tmp007_resume);

 static const struct of_device_id tmp007_of_match[] = {
 	{ .compatible = "ti,tmp007", },
 	{ },
 };
 MODULE_DEVICE_TABLE(of, tmp007_of_match);

 static const struct i2c_device_id tmp007_id[] = {
 	{ "tmp007", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, tmp007_id);

 static struct i2c_driver tmp007_driver = {
 	.driver = {
 		.name	= "tmp007",
 		.of_match_table = of_match_ptr(tmp007_of_match),
 		.pm	= &tmp007_pm_ops,
 	},
 	.probe		= tmp007_probe,
 	.remove		= tmp007_remove,
 	.id_table	= tmp007_id,
 };
 module_i2c_driver(tmp007_driver);

 MODULE_AUTHOR("Manivannan Sadhasivam <manivannanece23@gmail.com>");
 MODULE_DESCRIPTION("TI TMP007 IR thermopile sensor driver");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* tmp007.c - Support for TI TMP007 IR thermopile sensor with integrated math engine
	*
	* Copyright (c) 2017 Manivannan Sadhasivam <manivannanece23@gmail.com>
	*
	* Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
	*
	* (7-bit I2C slave address (0x40 - 0x47), changeable via ADR pins)
	*
	* Note:
	* 1. This driver assumes that the sensor has been calibrated beforehand
	* 2. Limit threshold events are enabled at the start
	* 3. Operating mode: INT
	*/

	#include <linux/err.h>
	#include <linux/i2c.h>
	#include <linux/delay.h>
	#include <linux/module.h>
	#include <linux/pm.h>
	#include <linux/bitops.h>
	#include <linux/of.h>
	#include <linux/irq.h>
	#include <linux/interrupt.h>

	#include <linux/iio/iio.h>
	#include <linux/iio/sysfs.h>
	#include <linux/iio/events.h>

	#define TMP007_TDIE 0x01
	#define TMP007_CONFIG 0x02
	#define TMP007_TOBJECT 0x03
	#define TMP007_STATUS 0x04
	#define TMP007_STATUS_MASK 0x05
	#define TMP007_TOBJ_HIGH_LIMIT 0x06
	#define TMP007_TOBJ_LOW_LIMIT 0x07
	#define TMP007_TDIE_HIGH_LIMIT 0x08
	#define TMP007_TDIE_LOW_LIMIT 0x09
	#define TMP007_MANUFACTURER_ID 0x1e
	#define TMP007_DEVICE_ID 0x1f

	#define TMP007_CONFIG_CONV_EN BIT(12)
	#define TMP007_CONFIG_TC_EN BIT(6)
	#define TMP007_CONFIG_CR_MASK GENMASK(11, 9)
	#define TMP007_CONFIG_ALERT_EN BIT(8)
	#define TMP007_CONFIG_CR_SHIFT 9

	/* Status register flags */
	#define TMP007_STATUS_ALERT BIT(15)
	#define TMP007_STATUS_CONV_READY BIT(14)
	#define TMP007_STATUS_OHF BIT(13)
	#define TMP007_STATUS_OLF BIT(12)
	#define TMP007_STATUS_LHF BIT(11)
	#define TMP007_STATUS_LLF BIT(10)
	#define TMP007_STATUS_DATA_VALID BIT(9)

	#define TMP007_MANUFACTURER_MAGIC 0x5449
	#define TMP007_DEVICE_MAGIC 0x0078

	#define TMP007_TEMP_SHIFT 2

	struct tmp007_data {
	struct i2c_client *client;
	struct mutex lock;
	u16 config;
	u16 status_mask;
	};

	static const int tmp007_avgs[5][2] = { {4, 0}, {2, 0}, {1, 0},
	{0, 500000}, {0, 250000} };

	static int tmp007_read_temperature(struct tmp007_data *data, u8 reg)
	{
	s32 ret;
	int tries = 50;

	while (tries-- > 0) {
	ret = i2c_smbus_read_word_swapped(data->client,
	TMP007_STATUS);
	if (ret < 0)
	return ret;
	if ((ret & TMP007_STATUS_CONV_READY) &&
	!(ret & TMP007_STATUS_DATA_VALID))
	break;
	msleep(100);
	}

	if (tries < 0)
	return -EIO;

	return i2c_smbus_read_word_swapped(data->client, reg);
	}

	static int tmp007_powerdown(struct tmp007_data *data)
	{
	return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
	data->config & ~TMP007_CONFIG_CONV_EN);
	}

	static int tmp007_read_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const channel, int val,
	int *val2, long mask)
	{
	struct tmp007_data *data = iio_priv(indio_dev);
	s32 ret;
	int conv_rate;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
	switch (channel->channel2) {
	case IIO_MOD_TEMP_AMBIENT: /* LSB: 0.03125 degree Celsius */
	ret = i2c_smbus_read_word_swapped(data->client, TMP007_TDIE);
	if (ret < 0)
	return ret;
	break;
	case IIO_MOD_TEMP_OBJECT:
	ret = tmp007_read_temperature(data, TMP007_TOBJECT);
	if (ret < 0)
	return ret;
	break;
	default:
	return -EINVAL;
	}

	*val = sign_extend32(ret, 15) >> TMP007_TEMP_SHIFT;

	return IIO_VAL_INT;
	case IIO_CHAN_INFO_SCALE:
	*val = 31;
	*val2 = 250000;

	return IIO_VAL_INT_PLUS_MICRO;
	case IIO_CHAN_INFO_SAMP_FREQ:
	conv_rate = (data->config & TMP007_CONFIG_CR_MASK)
	>> TMP007_CONFIG_CR_SHIFT;
	*val = tmp007_avgs[conv_rate][0];
	*val2 = tmp007_avgs[conv_rate][1];

	return IIO_VAL_INT_PLUS_MICRO;
	default:
	return -EINVAL;
	}
	}

	static int tmp007_write_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *channel, int val,
	int val2, long mask)
	{
	struct tmp007_data *data = iio_priv(indio_dev);
	int i;
	u16 tmp;

	if (mask == IIO_CHAN_INFO_SAMP_FREQ) {
	for (i = 0; i < ARRAY_SIZE(tmp007_avgs); i++) {
	if ((val == tmp007_avgs[i][0]) &&
	(val2 == tmp007_avgs[i][1])) {
	tmp = data->config & ~TMP007_CONFIG_CR_MASK;
	tmp \|= (i << TMP007_CONFIG_CR_SHIFT);

	return i2c_smbus_write_word_swapped(data->client,
	TMP007_CONFIG,
	data->config = tmp);
	}
	}
	}

	return -EINVAL;
	}

	static irqreturn_t tmp007_interrupt_handler(int irq, void *private)
	{
	struct iio_dev *indio_dev = private;
	struct tmp007_data *data = iio_priv(indio_dev);
	int ret;

	ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS);
	if ((ret < 0) \|\| !(ret & (TMP007_STATUS_OHF \| TMP007_STATUS_OLF \|
	TMP007_STATUS_LHF \| TMP007_STATUS_LLF)))
	return IRQ_NONE;

	if (ret & TMP007_STATUS_OHF)
	iio_push_event(indio_dev,
	IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
	IIO_MOD_TEMP_OBJECT,
	IIO_EV_TYPE_THRESH,
	IIO_EV_DIR_RISING),
	iio_get_time_ns(indio_dev));

	if (ret & TMP007_STATUS_OLF)
	iio_push_event(indio_dev,
	IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
	IIO_MOD_TEMP_OBJECT,
	IIO_EV_TYPE_THRESH,
	IIO_EV_DIR_FALLING),
	iio_get_time_ns(indio_dev));

	if (ret & TMP007_STATUS_LHF)
	iio_push_event(indio_dev,
	IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
	IIO_MOD_TEMP_AMBIENT,
	IIO_EV_TYPE_THRESH,
	IIO_EV_DIR_RISING),
	iio_get_time_ns(indio_dev));

	if (ret & TMP007_STATUS_LLF)
	iio_push_event(indio_dev,
	IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
	IIO_MOD_TEMP_AMBIENT,
	IIO_EV_TYPE_THRESH,
	IIO_EV_DIR_FALLING),
	iio_get_time_ns(indio_dev));

	return IRQ_HANDLED;
	}

	static int tmp007_write_event_config(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, enum iio_event_type type,
	enum iio_event_direction dir, int state)
	{
	struct tmp007_data *data = iio_priv(indio_dev);
	unsigned int status_mask;
	int ret;

	switch (chan->channel2) {
	case IIO_MOD_TEMP_AMBIENT:
	if (dir == IIO_EV_DIR_RISING)
	status_mask = TMP007_STATUS_LHF;
	else
	status_mask = TMP007_STATUS_LLF;
	break;
	case IIO_MOD_TEMP_OBJECT:
	if (dir == IIO_EV_DIR_RISING)
	status_mask = TMP007_STATUS_OHF;
	else
	status_mask = TMP007_STATUS_OLF;
	break;
	default:
	return -EINVAL;
	}

	mutex_lock(&data->lock);
	ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS_MASK);
	mutex_unlock(&data->lock);
	if (ret < 0)
	return ret;

	if (state)
	ret \|= status_mask;
	else
	ret &= ~status_mask;

	return i2c_smbus_write_word_swapped(data->client, TMP007_STATUS_MASK,
	data->status_mask = ret);
	}

	static int tmp007_read_event_config(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, enum iio_event_type type,
	enum iio_event_direction dir)
	{
	struct tmp007_data *data = iio_priv(indio_dev);
	unsigned int mask;

	switch (chan->channel2) {
	case IIO_MOD_TEMP_AMBIENT:
	if (dir == IIO_EV_DIR_RISING)
	mask = TMP007_STATUS_LHF;
	else
	mask = TMP007_STATUS_LLF;
	break;
	case IIO_MOD_TEMP_OBJECT:
	if (dir == IIO_EV_DIR_RISING)
	mask = TMP007_STATUS_OHF;
	else
	mask = TMP007_STATUS_OLF;
	break;
	default:
	return -EINVAL;
	}

	return !!(data->status_mask & mask);
	}

	static int tmp007_read_thresh(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, enum iio_event_type type,
	enum iio_event_direction dir, enum iio_event_info info,
	int val, int val2)
	{
	struct tmp007_data *data = iio_priv(indio_dev);
	int ret;
	u8 reg;

	switch (chan->channel2) {
	case IIO_MOD_TEMP_AMBIENT: /* LSB: 0.5 degree Celsius */
	if (dir == IIO_EV_DIR_RISING)
	reg = TMP007_TDIE_HIGH_LIMIT;
	else
	reg = TMP007_TDIE_LOW_LIMIT;
	break;
	case IIO_MOD_TEMP_OBJECT:
	if (dir == IIO_EV_DIR_RISING)
	reg = TMP007_TOBJ_HIGH_LIMIT;
	else
	reg = TMP007_TOBJ_LOW_LIMIT;
	break;
	default:
	return -EINVAL;
	}

	ret = i2c_smbus_read_word_swapped(data->client, reg);
	if (ret < 0)
	return ret;

	/* Shift length 7 bits = 6(15:6) + 1(0.5 LSB) */
	*val = sign_extend32(ret, 15) >> 7;

	return IIO_VAL_INT;
	}

	static int tmp007_write_thresh(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, enum iio_event_type type,
	enum iio_event_direction dir, enum iio_event_info info,
	int val, int val2)
	{
	struct tmp007_data *data = iio_priv(indio_dev);
	u8 reg;

	switch (chan->channel2) {
	case IIO_MOD_TEMP_AMBIENT:
	if (dir == IIO_EV_DIR_RISING)
	reg = TMP007_TDIE_HIGH_LIMIT;
	else
	reg = TMP007_TDIE_LOW_LIMIT;
	break;
	case IIO_MOD_TEMP_OBJECT:
	if (dir == IIO_EV_DIR_RISING)
	reg = TMP007_TOBJ_HIGH_LIMIT;
	else
	reg = TMP007_TOBJ_LOW_LIMIT;
	break;
	default:
	return -EINVAL;
	}

	/* Full scale threshold value is +/- 256 degree Celsius */
	if (val < -256 \|\| val > 255)
	return -EINVAL;

	/* Shift length 7 bits = 6(15:6) + 1(0.5 LSB) */
	return i2c_smbus_write_word_swapped(data->client, reg, (val << 7));
	}

	static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");

	static struct attribute *tmp007_attributes[] = {
	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
	NULL
	};

	static const struct attribute_group tmp007_attribute_group = {
	.attrs = tmp007_attributes,
	};

	static const struct iio_event_spec tmp007_obj_event[] = {
	{
	.type = IIO_EV_TYPE_THRESH,
	.dir = IIO_EV_DIR_RISING,
	.mask_separate = BIT(IIO_EV_INFO_VALUE) \|
	BIT(IIO_EV_INFO_ENABLE),
	},
	{
	.type = IIO_EV_TYPE_THRESH,
	.dir = IIO_EV_DIR_FALLING,
	.mask_separate = BIT(IIO_EV_INFO_VALUE) \|
	BIT(IIO_EV_INFO_ENABLE),
	},
	};

	static const struct iio_event_spec tmp007_die_event[] = {
	{
	.type = IIO_EV_TYPE_THRESH,
	.dir = IIO_EV_DIR_RISING,
	.mask_separate = BIT(IIO_EV_INFO_VALUE) \|
	BIT(IIO_EV_INFO_ENABLE),
	},
	{
	.type = IIO_EV_TYPE_THRESH,
	.dir = IIO_EV_DIR_FALLING,
	.mask_separate = BIT(IIO_EV_INFO_VALUE) \|
	BIT(IIO_EV_INFO_ENABLE),
	},
	};

	static const struct iio_chan_spec tmp007_channels[] = {
	{
	.type = IIO_TEMP,
	.modified = 1,
	.channel2 = IIO_MOD_TEMP_AMBIENT,
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) \|
	BIT(IIO_CHAN_INFO_SCALE),
	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
	.event_spec = tmp007_die_event,
	.num_event_specs = ARRAY_SIZE(tmp007_die_event),
	},
	{
	.type = IIO_TEMP,
	.modified = 1,
	.channel2 = IIO_MOD_TEMP_OBJECT,
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) \|
	BIT(IIO_CHAN_INFO_SCALE),
	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
	.event_spec = tmp007_obj_event,
	.num_event_specs = ARRAY_SIZE(tmp007_obj_event),
	}
	};

	static const struct iio_info tmp007_info = {
	.read_raw = tmp007_read_raw,
	.write_raw = tmp007_write_raw,
	.read_event_config = tmp007_read_event_config,
	.write_event_config = tmp007_write_event_config,
	.read_event_value = tmp007_read_thresh,
	.write_event_value = tmp007_write_thresh,
	.attrs = &tmp007_attribute_group,
	};

	static bool tmp007_identify(struct i2c_client *client)
	{
	int manf_id, dev_id;

	manf_id = i2c_smbus_read_word_swapped(client, TMP007_MANUFACTURER_ID);
	if (manf_id < 0)
	return false;

	dev_id = i2c_smbus_read_word_swapped(client, TMP007_DEVICE_ID);
	if (dev_id < 0)
	return false;

	return (manf_id == TMP007_MANUFACTURER_MAGIC && dev_id == TMP007_DEVICE_MAGIC);
	}

	static int tmp007_probe(struct i2c_client *client,
	const struct i2c_device_id *tmp007_id)
	{
	struct tmp007_data *data;
	struct iio_dev *indio_dev;
	int ret;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
	return -EOPNOTSUPP;

	if (!tmp007_identify(client)) {
	dev_err(&client->dev, "TMP007 not found\n");
	return -ENODEV;
	}

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

	data = iio_priv(indio_dev);
	i2c_set_clientdata(client, indio_dev);
	data->client = client;
	mutex_init(&data->lock);

	indio_dev->dev.parent = &client->dev;
	indio_dev->name = "tmp007";
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->info = &tmp007_info;

	indio_dev->channels = tmp007_channels;
	indio_dev->num_channels = ARRAY_SIZE(tmp007_channels);

	/*
	* Set Configuration register:
	* 1. Conversion ON
	* 2. ALERT enable
	* 3. Transient correction enable
	*/

	ret = i2c_smbus_read_word_swapped(data->client, TMP007_CONFIG);
	if (ret < 0)
	return ret;

	data->config = ret;
	data->config \|= (TMP007_CONFIG_CONV_EN \| TMP007_CONFIG_ALERT_EN \| TMP007_CONFIG_TC_EN);

	ret = i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
	data->config);
	if (ret < 0)
	return ret;

	/*
	* Only the following flags can activate ALERT pin. Data conversion/validity flags
	* flags can still be polled for getting temperature data
	*
	* Set Status Mask register:
	* 1. Object temperature high limit enable
	* 2. Object temperature low limit enable
	* 3. TDIE temperature high limit enable
	* 4. TDIE temperature low limit enable
	*/

	ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS_MASK);
	if (ret < 0)
	goto error_powerdown;

	data->status_mask = ret;
	data->status_mask \|= (TMP007_STATUS_OHF \| TMP007_STATUS_OLF
	\| TMP007_STATUS_LHF \| TMP007_STATUS_LLF);

	ret = i2c_smbus_write_word_swapped(data->client, TMP007_STATUS_MASK, data->status_mask);
	if (ret < 0)
	goto error_powerdown;

	if (client->irq) {
	ret = devm_request_threaded_irq(&client->dev, client->irq,
	NULL, tmp007_interrupt_handler,
	IRQF_TRIGGER_FALLING \| IRQF_ONESHOT,
	tmp007_id->name, indio_dev);
	if (ret) {
	dev_err(&client->dev, "irq request error %d\n", -ret);
	goto error_powerdown;
	}
	}

	return iio_device_register(indio_dev);

	error_powerdown:
	tmp007_powerdown(data);

	return ret;
	}

	static int tmp007_remove(struct i2c_client *client)
	{
	struct iio_dev *indio_dev = i2c_get_clientdata(client);
	struct tmp007_data *data = iio_priv(indio_dev);

	iio_device_unregister(indio_dev);
	tmp007_powerdown(data);

	return 0;
	}

	#ifdef CONFIG_PM_SLEEP
	static int tmp007_suspend(struct device *dev)
	{
	struct tmp007_data *data = iio_priv(i2c_get_clientdata(
	to_i2c_client(dev)));

	return tmp007_powerdown(data);
	}

	static int tmp007_resume(struct device *dev)
	{
	struct tmp007_data *data = iio_priv(i2c_get_clientdata(
	to_i2c_client(dev)));

	return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
	data->config \| TMP007_CONFIG_CONV_EN);
	}
	#endif

	static SIMPLE_DEV_PM_OPS(tmp007_pm_ops, tmp007_suspend, tmp007_resume);

	static const struct of_device_id tmp007_of_match[] = {
	{ .compatible = "ti,tmp007", },
	{ },
	};
	MODULE_DEVICE_TABLE(of, tmp007_of_match);

	static const struct i2c_device_id tmp007_id[] = {
	{ "tmp007", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, tmp007_id);

	static struct i2c_driver tmp007_driver = {
	.driver = {
	.name = "tmp007",
	.of_match_table = of_match_ptr(tmp007_of_match),
	.pm = &tmp007_pm_ops,
	},
	.probe = tmp007_probe,
	.remove = tmp007_remove,
	.id_table = tmp007_id,
	};
	module_i2c_driver(tmp007_driver);

	MODULE_AUTHOR("Manivannan Sadhasivam <manivannanece23@gmail.com>");
	MODULE_DESCRIPTION("TI TMP007 IR thermopile sensor driver");
	MODULE_LICENSE("GPL");