[deliverable/linux.git] / drivers / iio / pressure / t5403.c

/*
 * 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,
	.driver_module = THIS_MODULE,
};

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");
Commit	Line	Data
a2d8be68 PM	1	/*
	2	* t5403.c - Support for EPCOS T5403 pressure/temperature sensor
	3	*
	4	* Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
	5	*
	6	* This file is subject to the terms and conditions of version 2 of
	7	* the GNU General Public License. See the file COPYING in the main
	8	* directory of this archive for more details.
	9	*
	10	* (7-bit I2C slave address 0x77)
	11	*
	12	* TODO: end-of-conversion irq
	13	*/
	14
	15	#include <linux/module.h>
	16	#include <linux/i2c.h>
	17	#include <linux/iio/iio.h>
	18	#include <linux/iio/sysfs.h>
	19	#include <linux/delay.h>
	20
	21	#define T5403_DATA 0xf5 /* data, LSB first, 16 bit */
	22	#define T5403_CALIB_DATA 0x8e /* 10 calibration coeff., LSB first, 16 bit */
	23	#define T5403_SLAVE_ADDR 0x88 /* I2C slave address, 0x77 */
	24	#define T5403_COMMAND 0xf1
	25
	26	/* command bits */
	27	#define T5403_MODE_SHIFT 3 /* conversion time: 2, 8, 16, 66 ms */
	28	#define T5403_PT BIT(1) /* 0 .. pressure, 1 .. temperature measurement */
	29	#define T5403_SCO BIT(0) /* start conversion */
	30
	31	#define T5403_MODE_LOW 0
	32	#define T5403_MODE_STANDARD 1
	33	#define T5403_MODE_HIGH 2
	34	#define T5403_MODE_ULTRA_HIGH 3
	35
	36	#define T5403_I2C_MASK (~BIT(7))
	37	#define T5403_I2C_ADDR 0x77
	38
	39	static const int t5403_pressure_conv_ms[] = {2, 8, 16, 66};
	40
	41	struct t5403_data {
	42	struct i2c_client *client;
	43	struct mutex lock;
	44	int mode;
	45	__le16 c[10];
	46	};
	47
	48	#define T5403_C_U16(i) le16_to_cpu(data->c[(i) - 1])
	49	#define T5403_C(i) sign_extend32(T5403_C_U16(i), 15)
	50
	51	static int t5403_read(struct t5403_data *data, bool pressure)
	52	{
	53	int wait_time = 3; /* wakeup time in ms */
	54
	55	int ret = i2c_smbus_write_byte_data(data->client, T5403_COMMAND,
	56	(pressure ? (data->mode << T5403_MODE_SHIFT) : T5403_PT) \|
	57	T5403_SCO);
	58	if (ret < 0)
	59	return ret;
	60
	61	wait_time += pressure ? t5403_pressure_conv_ms[data->mode] : 2;
	62
	63	msleep(wait_time);
	64
65	return i2c_smbus_read_word_data(data->client, T5403_DATA);
66	}
67
68	static int t5403_comp_pressure(struct t5403_data data, int val, int *val2)
69	{
70	int ret;
71	s16 t_r;
72	u16 p_r;
73	s32 S, O, X;
74
75	mutex_lock(&data->lock);
76
77	ret = t5403_read(data, false);
78	if (ret < 0)
79	goto done;
80	t_r = ret;
81
82	ret = t5403_read(data, true);
83	if (ret < 0)
84	goto done;
85	p_r = ret;
86
87	/* see EPCOS application note */
88	S = T5403_C_U16(3) + (s32) T5403_C_U16(4) * t_r / 0x20000 +
89	T5403_C(5) * t_r / 0x8000 * t_r / 0x80000 +
90	T5403_C(9) * t_r / 0x8000 * t_r / 0x8000 * t_r / 0x10000;
91
92	O = T5403_C(6) * 0x4000 + T5403_C(7) * t_r / 8 +
93	T5403_C(8) * t_r / 0x8000 * t_r / 16 +
94	T5403_C(9) * t_r / 0x8000 * t_r / 0x10000 * t_r;
95
96	X = (S * p_r + O) / 0x4000;
97
98	X += ((X - 75000) * (X - 75000) / 0x10000 - 9537) *
99	T5403_C(10) / 0x10000;
100
101	*val = X / 1000;
102	val2 = (X % 1000) 1000;
103
104	done:
105	mutex_unlock(&data->lock);
106	return ret;
107	}
108
109	static int t5403_comp_temp(struct t5403_data data, int val)
110	{
111	int ret;
112	s16 t_r;
113
114	mutex_lock(&data->lock);
115	ret = t5403_read(data, false);
116	if (ret < 0)
117	goto done;
118	t_r = ret;
119
120	/* see EPCOS application note */
121	val = ((s32) T5403_C_U16(1) t_r / 0x100 +
122	(s32) T5403_C_U16(2) * 0x40) * 1000 / 0x10000;
123
124	done:
125	mutex_unlock(&data->lock);
126	return ret;
127	}
128
129	static int t5403_read_raw(struct iio_dev *indio_dev,
130	struct iio_chan_spec const *chan,
131	int val, int val2, long mask)
132	{
133	struct t5403_data *data = iio_priv(indio_dev);
134	int ret;
135
136	switch (mask) {
137	case IIO_CHAN_INFO_PROCESSED:
138	switch (chan->type) {
139	case IIO_PRESSURE:
140	ret = t5403_comp_pressure(data, val, val2);
141	if (ret < 0)
142	return ret;
143	return IIO_VAL_INT_PLUS_MICRO;
144	case IIO_TEMP:
145	ret = t5403_comp_temp(data, val);
146	if (ret < 0)
147	return ret;
148	return IIO_VAL_INT;
149	default:
150	return -EINVAL;
151	}
152	case IIO_CHAN_INFO_INT_TIME:
153	*val = 0;
154	val2 = t5403_pressure_conv_ms[data->mode] 1000;
155	return IIO_VAL_INT_PLUS_MICRO;
156	default:
157	return -EINVAL;
158	}
159	}
160
161	static int t5403_write_raw(struct iio_dev *indio_dev,
162	struct iio_chan_spec const *chan,
163	int val, int val2, long mask)
164	{
165	struct t5403_data *data = iio_priv(indio_dev);
166	int i;
167
168	switch (mask) {
169	case IIO_CHAN_INFO_INT_TIME:
170	if (val != 0)
171	return -EINVAL;
172	for (i = 0; i < ARRAY_SIZE(t5403_pressure_conv_ms); i++)
173	if (val2 == t5403_pressure_conv_ms[i] * 1000) {
174	mutex_lock(&data->lock);
175	data->mode = i;
176	mutex_unlock(&data->lock);
177	return 0;
178	}
179	return -EINVAL;
180	default:
181	return -EINVAL;
182	}
183	}
184
185	static const struct iio_chan_spec t5403_channels[] = {
186	{
187	.type = IIO_PRESSURE,
188	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) \|
189	BIT(IIO_CHAN_INFO_INT_TIME),
190	},
191	{
192	.type = IIO_TEMP,
193	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
194	},
195	};
196
197	static IIO_CONST_ATTR_INT_TIME_AVAIL("0.002 0.008 0.016 0.066");
198
199	static struct attribute *t5403_attributes[] = {
200	&iio_const_attr_integration_time_available.dev_attr.attr,
201	NULL
202	};
203
204	static const struct attribute_group t5403_attribute_group = {
205	.attrs = t5403_attributes,
206	};
207
208	static const struct iio_info t5403_info = {
209	.read_raw = &t5403_read_raw,
210	.write_raw = &t5403_write_raw,
211	.attrs = &t5403_attribute_group,
212	.driver_module = THIS_MODULE,
213	};
214
215	static int t5403_probe(struct i2c_client *client,
216	const struct i2c_device_id *id)
217	{
218	struct t5403_data *data;
219	struct iio_dev *indio_dev;
220	int ret;
221
222	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA \|
223	I2C_FUNC_SMBUS_I2C_BLOCK))
f8d9d3b4	224	return -EOPNOTSUPP;
a2d8be68 PM	225
	226	ret = i2c_smbus_read_byte_data(client, T5403_SLAVE_ADDR);
	227	if (ret < 0)
	228	return ret;
	229	if ((ret & T5403_I2C_MASK) != T5403_I2C_ADDR)
	230	return -ENODEV;
	231
	232	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
	233	if (!indio_dev)
	234	return -ENOMEM;
	235
	236	data = iio_priv(indio_dev);
	237	data->client = client;
	238	mutex_init(&data->lock);
	239
	240	i2c_set_clientdata(client, indio_dev);
	241	indio_dev->info = &t5403_info;
	242	indio_dev->name = id->name;
	243	indio_dev->dev.parent = &client->dev;
	244	indio_dev->modes = INDIO_DIRECT_MODE;
	245	indio_dev->channels = t5403_channels;
	246	indio_dev->num_channels = ARRAY_SIZE(t5403_channels);
	247
	248	data->mode = T5403_MODE_STANDARD;
	249
	250	ret = i2c_smbus_read_i2c_block_data(data->client, T5403_CALIB_DATA,
	251	sizeof(data->c), (u8 *) data->c);
	252	if (ret < 0)
	253	return ret;
	254
	255	return devm_iio_device_register(&client->dev, indio_dev);
	256	}
	257
	258	static const struct i2c_device_id t5403_id[] = {
	259	{ "t5403", 0 },
	260	{ }
	261	};
	262	MODULE_DEVICE_TABLE(i2c, t5403_id);
	263
	264	static struct i2c_driver t5403_driver = {
	265	.driver = {
	266	.name = "t5403",
	267	},
	268	.probe = t5403_probe,
	269	.id_table = t5403_id,
	270	};
	271	module_i2c_driver(t5403_driver);
	272
	273	MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
	274	MODULE_DESCRIPTION("EPCOS T5403 pressure/temperature sensor driver");
	275	MODULE_LICENSE("GPL");