summaryrefslogtreecommitdiffstats
path: root/drivers/iio/temperature/tmp006.c
blob: a9b5b7cc7836fa2800cc732cd03bca920fd59b91 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
/*
 * tmp006.c - Support for TI TMP006 IR thermopile sensor
 *
 * Copyright (c) 2013 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.
 *
 * Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
 *
 * (7-bit I2C slave address 0x40, changeable via ADR pins)
 *
 * TODO: data ready irq
 */

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

#define TMP006_VOBJECT 0x00
#define TMP006_TAMBIENT 0x01
#define TMP006_CONFIG 0x02
#define TMP006_MANUFACTURER_ID 0xfe
#define TMP006_DEVICE_ID 0xff

#define TMP006_TAMBIENT_SHIFT 2

#define TMP006_CONFIG_RESET BIT(15)
#define TMP006_CONFIG_DRDY_EN BIT(8)
#define TMP006_CONFIG_DRDY BIT(7)

#define TMP006_CONFIG_MOD_MASK GENMASK(14, 12)

#define TMP006_CONFIG_CR_MASK GENMASK(11, 9)
#define TMP006_CONFIG_CR_SHIFT 9

#define TMP006_MANUFACTURER_MAGIC 0x5449
#define TMP006_DEVICE_MAGIC 0x0067

struct tmp006_data {
	struct i2c_client *client;
	u16 config;
};

static int tmp006_read_measurement(struct tmp006_data *data, u8 reg)
{
	s32 ret;
	int tries = 50;

	while (tries-- > 0) {
		ret = i2c_smbus_read_word_swapped(data->client,
			TMP006_CONFIG);
		if (ret < 0)
			return ret;
		if (ret & TMP006_CONFIG_DRDY)
			break;
		msleep(100);
	}

	if (tries < 0)
		return -EIO;

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

static const int tmp006_freqs[5][2] = { {4, 0}, {2, 0}, {1, 0},
					{0, 500000}, {0, 250000} };

static int tmp006_read_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *channel, int *val,
			    int *val2, long mask)
{
	struct tmp006_data *data = iio_priv(indio_dev);
	s32 ret;
	int cr;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		if (channel->type == IIO_VOLTAGE) {
			/* LSB is 156.25 nV */
			ret = tmp006_read_measurement(data, TMP006_VOBJECT);
			if (ret < 0)
				return ret;
			*val = sign_extend32(ret, 15);
		} else if (channel->type == IIO_TEMP) {
			/* LSB is 0.03125 degrees Celsius */
			ret = tmp006_read_measurement(data, TMP006_TAMBIENT);
			if (ret < 0)
				return ret;
			*val = sign_extend32(ret, 15) >> TMP006_TAMBIENT_SHIFT;
		} else {
			break;
		}
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_SCALE:
		if (channel->type == IIO_VOLTAGE) {
			*val = 0;
			*val2 = 156250;
		} else if (channel->type == IIO_TEMP) {
			*val = 31;
			*val2 = 250000;
		} else {
			break;
		}
		return IIO_VAL_INT_PLUS_MICRO;
	case IIO_CHAN_INFO_SAMP_FREQ:
		cr = (data->config & TMP006_CONFIG_CR_MASK)
			>> TMP006_CONFIG_CR_SHIFT;
		*val = tmp006_freqs[cr][0];
		*val2 = tmp006_freqs[cr][1];
		return IIO_VAL_INT_PLUS_MICRO;
	default:
		break;
	}

	return -EINVAL;
}

static int tmp006_write_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *chan,
			    int val,
			    int val2,
			    long mask)
{
	struct tmp006_data *data = iio_priv(indio_dev);
	int i;

	if (mask != IIO_CHAN_INFO_SAMP_FREQ)
		return -EINVAL;

	for (i = 0; i < ARRAY_SIZE(tmp006_freqs); i++)
		if ((val == tmp006_freqs[i][0]) &&
		    (val2 == tmp006_freqs[i][1])) {
			data->config &= ~TMP006_CONFIG_CR_MASK;
			data->config |= i << TMP006_CONFIG_CR_SHIFT;

			return i2c_smbus_write_word_swapped(data->client,
							    TMP006_CONFIG,
							    data->config);

		}
	return -EINVAL;
}

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

static struct attribute *tmp006_attributes[] = {
	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
	NULL
};

static const struct attribute_group tmp006_attribute_group = {
	.attrs = tmp006_attributes,
};

static const struct iio_chan_spec tmp006_channels[] = {
	{
		.type = IIO_VOLTAGE,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
			BIT(IIO_CHAN_INFO_SCALE),
		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
	},
	{
		.type = IIO_TEMP,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
			BIT(IIO_CHAN_INFO_SCALE),
		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
	}
};

static const struct iio_info tmp006_info = {
	.read_raw = tmp006_read_raw,
	.write_raw = tmp006_write_raw,
	.attrs = &tmp006_attribute_group,
};

static bool tmp006_check_identification(struct i2c_client *client)
{
	int mid, did;

	mid = i2c_smbus_read_word_swapped(client, TMP006_MANUFACTURER_ID);
	if (mid < 0)
		return false;

	did = i2c_smbus_read_word_swapped(client, TMP006_DEVICE_ID);
	if (did < 0)
		return false;

	return mid == TMP006_MANUFACTURER_MAGIC && did == TMP006_DEVICE_MAGIC;
}

static int tmp006_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct iio_dev *indio_dev;
	struct tmp006_data *data;
	int ret;

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

	if (!tmp006_check_identification(client)) {
		dev_err(&client->dev, "no TMP006 sensor\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;

	indio_dev->dev.parent = &client->dev;
	indio_dev->name = dev_name(&client->dev);
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->info = &tmp006_info;

	indio_dev->channels = tmp006_channels;
	indio_dev->num_channels = ARRAY_SIZE(tmp006_channels);

	ret = i2c_smbus_read_word_swapped(data->client, TMP006_CONFIG);
	if (ret < 0)
		return ret;
	data->config = ret;

	return iio_device_register(indio_dev);
}

static int tmp006_powerdown(struct tmp006_data *data)
{
	return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
		data->config & ~TMP006_CONFIG_MOD_MASK);
}

static int tmp006_remove(struct i2c_client *client)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(client);

	iio_device_unregister(indio_dev);
	tmp006_powerdown(iio_priv(indio_dev));

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int tmp006_suspend(struct device *dev)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
	return tmp006_powerdown(iio_priv(indio_dev));
}

static int tmp006_resume(struct device *dev)
{
	struct tmp006_data *data = iio_priv(i2c_get_clientdata(
		to_i2c_client(dev)));
	return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
		data->config | TMP006_CONFIG_MOD_MASK);
}
#endif

static SIMPLE_DEV_PM_OPS(tmp006_pm_ops, tmp006_suspend, tmp006_resume);

static const struct i2c_device_id tmp006_id[] = {
	{ "tmp006", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, tmp006_id);

static struct i2c_driver tmp006_driver = {
	.driver = {
		.name	= "tmp006",
		.pm	= &tmp006_pm_ops,
	},
	.probe = tmp006_probe,
	.remove = tmp006_remove,
	.id_table = tmp006_id,
};
module_i2c_driver(tmp006_driver);

MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_DESCRIPTION("TI TMP006 IR thermopile sensor driver");
MODULE_LICENSE("GPL");