drivers/iio/pressure/t5403.c - linux-mtk - Git at Google

 /*
  * t5403.c - Support for EPCOS T5403 pressure/temperature sensor
  *
  * Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
  *
  * This file is subject to the terms and conditions of version 2 of
  * the GNU General Public License.  See the file COPYING in the main
  * directory of this archive for more details.
  *
  * (7-bit I2C slave address 0x77)
  *
  * TODO: end-of-conversion irq
  */

 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
 #include <linux/delay.h>

 #define T5403_DATA 0xf5 /* data, LSB first, 16 bit */
 #define T5403_CALIB_DATA 0x8e /* 10 calibration coeff., LSB first, 16 bit */
 #define T5403_SLAVE_ADDR 0x88 /* I2C slave address, 0x77 */
 #define T5403_COMMAND 0xf1

 /* command bits */
 #define T5403_MODE_SHIFT 3 /* conversion time: 2, 8, 16, 66 ms */
 #define T5403_PT BIT(1) /* 0 .. pressure, 1 .. temperature measurement */
 #define T5403_SCO BIT(0) /* start conversion */

 #define T5403_MODE_LOW 0
 #define T5403_MODE_STANDARD 1
 #define T5403_MODE_HIGH 2
 #define T5403_MODE_ULTRA_HIGH 3

 #define T5403_I2C_MASK (~BIT(7))
 #define T5403_I2C_ADDR 0x77

 static const int t5403_pressure_conv_ms[] = {2, 8, 16, 66};

 struct t5403_data {
 	struct i2c_client *client;
 	struct mutex lock;
 	int mode;
 	__le16 c[10];
 };

 #define T5403_C_U16(i) le16_to_cpu(data->c[(i) - 1])
 #define T5403_C(i) sign_extend32(T5403_C_U16(i), 15)

 static int t5403_read(struct t5403_data *data, bool pressure)
 {
 	int wait_time = 3;  /* wakeup time in ms */

 	int ret = i2c_smbus_write_byte_data(data->client, T5403_COMMAND,
 		(pressure ? (data->mode << T5403_MODE_SHIFT) : T5403_PT) |
 		T5403_SCO);
 	if (ret < 0)
 		return ret;

 	wait_time += pressure ? t5403_pressure_conv_ms[data->mode] : 2;

 	msleep(wait_time);

 	return i2c_smbus_read_word_data(data->client, T5403_DATA);
 }

 static int t5403_comp_pressure(struct t5403_data *data, int *val, int *val2)
 {
 	int ret;
 	s16 t_r;
 	u16 p_r;
 	s32 S, O, X;

 	mutex_lock(&data->lock);

 	ret = t5403_read(data, false);
 	if (ret < 0)
 		goto done;
 	t_r = ret;

 	ret = t5403_read(data, true);
 	if (ret < 0)
 		goto done;
 	p_r = ret;

 	/* see EPCOS application note */
 	S = T5403_C_U16(3) + (s32) T5403_C_U16(4) * t_r / 0x20000 +
 		T5403_C(5) * t_r / 0x8000 * t_r / 0x80000 +
 		T5403_C(9) * t_r / 0x8000 * t_r / 0x8000 * t_r / 0x10000;

 	O = T5403_C(6) * 0x4000 + T5403_C(7) * t_r / 8 +
 		T5403_C(8) * t_r / 0x8000 * t_r / 16 +
 		T5403_C(9) * t_r / 0x8000 * t_r / 0x10000 * t_r;

 	X = (S * p_r + O) / 0x4000;

 	X += ((X - 75000) * (X - 75000) / 0x10000 - 9537) *
 	    T5403_C(10) / 0x10000;

 	*val = X / 1000;
 	*val2 = (X % 1000) * 1000;

 done:
 	mutex_unlock(&data->lock);
 	return ret;
 }

 static int t5403_comp_temp(struct t5403_data *data, int *val)
 {
 	int ret;
 	s16 t_r;

 	mutex_lock(&data->lock);
 	ret = t5403_read(data, false);
 	if (ret < 0)
 		goto done;
 	t_r = ret;

 	/* see EPCOS application note */
 	*val = ((s32) T5403_C_U16(1) * t_r / 0x100 +
 		(s32) T5403_C_U16(2) * 0x40) * 1000 / 0x10000;

 done:
 	mutex_unlock(&data->lock);
 	return ret;
 }

 static int t5403_read_raw(struct iio_dev *indio_dev,
 			  struct iio_chan_spec const *chan,
 			  int *val, int *val2, long mask)
 {
 	struct t5403_data *data = iio_priv(indio_dev);
 	int ret;

 	switch (mask) {
 	case IIO_CHAN_INFO_PROCESSED:
 		switch (chan->type) {
 		case IIO_PRESSURE:
 			ret = t5403_comp_pressure(data, val, val2);
 			if (ret < 0)
 				return ret;
 			return IIO_VAL_INT_PLUS_MICRO;
 		case IIO_TEMP:
 			ret = t5403_comp_temp(data, val);
 			if (ret < 0)
 				return ret;
 			return IIO_VAL_INT;
 		default:
 			return -EINVAL;
 	    }
 	case IIO_CHAN_INFO_INT_TIME:
 		*val = 0;
 		*val2 = t5403_pressure_conv_ms[data->mode] * 1000;
 		return IIO_VAL_INT_PLUS_MICRO;
 	default:
 		return -EINVAL;
 	}
 }

 static int t5403_write_raw(struct iio_dev *indio_dev,
 			   struct iio_chan_spec const *chan,
 			   int val, int val2, long mask)
 {
 	struct t5403_data *data = iio_priv(indio_dev);
 	int i;

 	switch (mask) {
 	case IIO_CHAN_INFO_INT_TIME:
 		if (val != 0)
 			return -EINVAL;
 		for (i = 0; i < ARRAY_SIZE(t5403_pressure_conv_ms); i++)
 			if (val2 == t5403_pressure_conv_ms[i] * 1000) {
 				mutex_lock(&data->lock);
 				data->mode = i;
 				mutex_unlock(&data->lock);
 				return 0;
 			}
 		return -EINVAL;
 	default:
 		return -EINVAL;
 	}
 }

 static const struct iio_chan_spec t5403_channels[] = {
 	{
 		.type = IIO_PRESSURE,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
 		    BIT(IIO_CHAN_INFO_INT_TIME),
 	},
 	{
 		.type = IIO_TEMP,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
 	},
 };

 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.002 0.008 0.016 0.066");

 static struct attribute *t5403_attributes[] = {
 	&iio_const_attr_integration_time_available.dev_attr.attr,
 	NULL
 };

 static const struct attribute_group t5403_attribute_group = {
 	.attrs = t5403_attributes,
 };

 static const struct iio_info t5403_info = {
 	.read_raw = &t5403_read_raw,
 	.write_raw = &t5403_write_raw,
 	.attrs = &t5403_attribute_group,
 };

 static int t5403_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id)
 {
 	struct t5403_data *data;
 	struct iio_dev *indio_dev;
 	int ret;

 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA |
 	    I2C_FUNC_SMBUS_I2C_BLOCK))
 		return -EOPNOTSUPP;

 	ret = i2c_smbus_read_byte_data(client, T5403_SLAVE_ADDR);
 	if (ret < 0)
 		return ret;
 	if ((ret & T5403_I2C_MASK) != T5403_I2C_ADDR)
 		return -ENODEV;

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

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

 	i2c_set_clientdata(client, indio_dev);
 	indio_dev->info = &t5403_info;
 	indio_dev->name = id->name;
 	indio_dev->dev.parent = &client->dev;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->channels = t5403_channels;
 	indio_dev->num_channels = ARRAY_SIZE(t5403_channels);

 	data->mode = T5403_MODE_STANDARD;

 	ret = i2c_smbus_read_i2c_block_data(data->client, T5403_CALIB_DATA,
 	    sizeof(data->c), (u8 *) data->c);
 	if (ret < 0)
 		return ret;

 	return devm_iio_device_register(&client->dev, indio_dev);
 }

 static const struct i2c_device_id t5403_id[] = {
 	{ "t5403", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, t5403_id);

 static struct i2c_driver t5403_driver = {
 	.driver = {
 		.name	= "t5403",
 	},
 	.probe = t5403_probe,
 	.id_table = t5403_id,
 };
 module_i2c_driver(t5403_driver);

 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 MODULE_DESCRIPTION("EPCOS T5403 pressure/temperature sensor driver");
 MODULE_LICENSE("GPL");
	/*
	* t5403.c - Support for EPCOS T5403 pressure/temperature sensor
	*
	* Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
	*
	* This file is subject to the terms and conditions of version 2 of
	* the GNU General Public License. See the file COPYING in the main
	* directory of this archive for more details.
	*
	* (7-bit I2C slave address 0x77)
	*
	* TODO: end-of-conversion irq
	*/

	#include <linux/module.h>
	#include <linux/i2c.h>
	#include <linux/iio/iio.h>
	#include <linux/iio/sysfs.h>
	#include <linux/delay.h>

	#define T5403_DATA 0xf5 /* data, LSB first, 16 bit */
	#define T5403_CALIB_DATA 0x8e /* 10 calibration coeff., LSB first, 16 bit */
	#define T5403_SLAVE_ADDR 0x88 /* I2C slave address, 0x77 */
	#define T5403_COMMAND 0xf1

	/* command bits */
	#define T5403_MODE_SHIFT 3 /* conversion time: 2, 8, 16, 66 ms */
	#define T5403_PT BIT(1) /* 0 .. pressure, 1 .. temperature measurement */
	#define T5403_SCO BIT(0) /* start conversion */

	#define T5403_MODE_LOW 0
	#define T5403_MODE_STANDARD 1
	#define T5403_MODE_HIGH 2
	#define T5403_MODE_ULTRA_HIGH 3

	#define T5403_I2C_MASK (~BIT(7))
	#define T5403_I2C_ADDR 0x77

	static const int t5403_pressure_conv_ms[] = {2, 8, 16, 66};

	struct t5403_data {
	struct i2c_client *client;
	struct mutex lock;
	int mode;
	__le16 c[10];
	};

	#define T5403_C_U16(i) le16_to_cpu(data->c[(i) - 1])
	#define T5403_C(i) sign_extend32(T5403_C_U16(i), 15)

	static int t5403_read(struct t5403_data *data, bool pressure)
	{
	int wait_time = 3; /* wakeup time in ms */

	int ret = i2c_smbus_write_byte_data(data->client, T5403_COMMAND,
	(pressure ? (data->mode << T5403_MODE_SHIFT) : T5403_PT) \|
	T5403_SCO);
	if (ret < 0)
	return ret;

	wait_time += pressure ? t5403_pressure_conv_ms[data->mode] : 2;

	msleep(wait_time);

	return i2c_smbus_read_word_data(data->client, T5403_DATA);
	}

	static int t5403_comp_pressure(struct t5403_data data, int val, int *val2)
	{
	int ret;
	s16 t_r;
	u16 p_r;
	s32 S, O, X;

	mutex_lock(&data->lock);

	ret = t5403_read(data, false);
	if (ret < 0)
	goto done;
	t_r = ret;

	ret = t5403_read(data, true);
	if (ret < 0)
	goto done;
	p_r = ret;

	/* see EPCOS application note */
	S = T5403_C_U16(3) + (s32) T5403_C_U16(4) * t_r / 0x20000 +
	T5403_C(5) * t_r / 0x8000 * t_r / 0x80000 +
	T5403_C(9) * t_r / 0x8000 * t_r / 0x8000 * t_r / 0x10000;

	O = T5403_C(6) * 0x4000 + T5403_C(7) * t_r / 8 +
	T5403_C(8) * t_r / 0x8000 * t_r / 16 +
	T5403_C(9) * t_r / 0x8000 * t_r / 0x10000 * t_r;

	X = (S * p_r + O) / 0x4000;

	X += ((X - 75000) * (X - 75000) / 0x10000 - 9537) *
	T5403_C(10) / 0x10000;

	*val = X / 1000;
	val2 = (X % 1000) 1000;

	done:
	mutex_unlock(&data->lock);
	return ret;
	}

	static int t5403_comp_temp(struct t5403_data data, int val)
	{
	int ret;
	s16 t_r;

	mutex_lock(&data->lock);
	ret = t5403_read(data, false);
	if (ret < 0)
	goto done;
	t_r = ret;

	/* see EPCOS application note */
	val = ((s32) T5403_C_U16(1) t_r / 0x100 +
	(s32) T5403_C_U16(2) * 0x40) * 1000 / 0x10000;

	done:
	mutex_unlock(&data->lock);
	return ret;
	}

	static int t5403_read_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val, int val2, long mask)
	{
	struct t5403_data *data = iio_priv(indio_dev);
	int ret;

	switch (mask) {
	case IIO_CHAN_INFO_PROCESSED:
	switch (chan->type) {
	case IIO_PRESSURE:
	ret = t5403_comp_pressure(data, val, val2);
	if (ret < 0)
	return ret;
	return IIO_VAL_INT_PLUS_MICRO;
	case IIO_TEMP:
	ret = t5403_comp_temp(data, val);
	if (ret < 0)
	return ret;
	return IIO_VAL_INT;
	default:
	return -EINVAL;
	}
	case IIO_CHAN_INFO_INT_TIME:
	*val = 0;
	val2 = t5403_pressure_conv_ms[data->mode] 1000;
	return IIO_VAL_INT_PLUS_MICRO;
	default:
	return -EINVAL;
	}
	}

	static int t5403_write_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val, int val2, long mask)
	{
	struct t5403_data *data = iio_priv(indio_dev);
	int i;

	switch (mask) {
	case IIO_CHAN_INFO_INT_TIME:
	if (val != 0)
	return -EINVAL;
	for (i = 0; i < ARRAY_SIZE(t5403_pressure_conv_ms); i++)
	if (val2 == t5403_pressure_conv_ms[i] * 1000) {
	mutex_lock(&data->lock);
	data->mode = i;
	mutex_unlock(&data->lock);
	return 0;
	}
	return -EINVAL;
	default:
	return -EINVAL;
	}
	}

	static const struct iio_chan_spec t5403_channels[] = {
	{
	.type = IIO_PRESSURE,
	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) \|
	BIT(IIO_CHAN_INFO_INT_TIME),
	},
	{
	.type = IIO_TEMP,
	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
	},
	};

	static IIO_CONST_ATTR_INT_TIME_AVAIL("0.002 0.008 0.016 0.066");

	static struct attribute *t5403_attributes[] = {
	&iio_const_attr_integration_time_available.dev_attr.attr,
	NULL
	};

	static const struct attribute_group t5403_attribute_group = {
	.attrs = t5403_attributes,
	};

	static const struct iio_info t5403_info = {
	.read_raw = &t5403_read_raw,
	.write_raw = &t5403_write_raw,
	.attrs = &t5403_attribute_group,
	};

	static int t5403_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	struct t5403_data *data;
	struct iio_dev *indio_dev;
	int ret;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA \|
	I2C_FUNC_SMBUS_I2C_BLOCK))
	return -EOPNOTSUPP;

	ret = i2c_smbus_read_byte_data(client, T5403_SLAVE_ADDR);
	if (ret < 0)
	return ret;
	if ((ret & T5403_I2C_MASK) != T5403_I2C_ADDR)
	return -ENODEV;

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

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

	i2c_set_clientdata(client, indio_dev);
	indio_dev->info = &t5403_info;
	indio_dev->name = id->name;
	indio_dev->dev.parent = &client->dev;
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->channels = t5403_channels;
	indio_dev->num_channels = ARRAY_SIZE(t5403_channels);

	data->mode = T5403_MODE_STANDARD;

	ret = i2c_smbus_read_i2c_block_data(data->client, T5403_CALIB_DATA,
	sizeof(data->c), (u8 *) data->c);
	if (ret < 0)
	return ret;

	return devm_iio_device_register(&client->dev, indio_dev);
	}

	static const struct i2c_device_id t5403_id[] = {
	{ "t5403", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, t5403_id);

	static struct i2c_driver t5403_driver = {
	.driver = {
	.name = "t5403",
	},
	.probe = t5403_probe,
	.id_table = t5403_id,
	};
	module_i2c_driver(t5403_driver);

	MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
	MODULE_DESCRIPTION("EPCOS T5403 pressure/temperature sensor driver");
	MODULE_LICENSE("GPL");