summaryrefslogtreecommitdiffstats
path: root/drivers/iio/temperature/tmp117.c
blob: 8972083d903a2597b8ba2539d3f5d233c5b0371e (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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Digital temperature sensor with integrated Non-volatile memory
 * Copyright (c) 2021 Puranjay Mohan <puranjay12@gmail.com>
 *
 * Driver for the Texas Instruments TMP117 Temperature Sensor
 * (7-bit I2C slave address (0x48 - 0x4B), changeable via ADD pins)
 *
 * Note: This driver assumes that the sensor has been calibrated beforehand.
 */

#include <linux/delay.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/bitops.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/limits.h>
#include <linux/property.h>
#include <linux/regulator/consumer.h>

#include <linux/iio/iio.h>

#define TMP117_REG_TEMP			0x0
#define TMP117_REG_CFGR			0x1
#define TMP117_REG_HIGH_LIM		0x2
#define TMP117_REG_LOW_LIM		0x3
#define TMP117_REG_EEPROM_UL		0x4
#define TMP117_REG_EEPROM1		0x5
#define TMP117_REG_EEPROM2		0x6
#define TMP117_REG_TEMP_OFFSET		0x7
#define TMP117_REG_EEPROM3		0x8
#define TMP117_REG_DEVICE_ID		0xF

#define TMP117_RESOLUTION_10UC		78125
#define MICRODEGREE_PER_10MILLIDEGREE	10000

#define TMP116_DEVICE_ID		0x1116
#define TMP117_DEVICE_ID		0x0117

struct tmp117_data {
	struct i2c_client *client;
	s16 calibbias;
};

struct tmp11x_info {
	const char *name;
	struct iio_chan_spec const *channels;
	int num_channels;
};

static int tmp117_read_raw(struct iio_dev *indio_dev,
			   struct iio_chan_spec const *channel, int *val,
			   int *val2, long mask)
{
	struct tmp117_data *data = iio_priv(indio_dev);
	s32 ret;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		ret = i2c_smbus_read_word_swapped(data->client,
						  TMP117_REG_TEMP);
		if (ret < 0)
			return ret;
		*val = sign_extend32(ret, 15);
		return IIO_VAL_INT;

	case IIO_CHAN_INFO_CALIBBIAS:
		ret = i2c_smbus_read_word_swapped(data->client,
						  TMP117_REG_TEMP_OFFSET);
		if (ret < 0)
			return ret;
		*val = sign_extend32(ret, 15);
		return IIO_VAL_INT;

	case IIO_CHAN_INFO_SCALE:
		/*
		 * Conversion from 10s of uC to mC
		 * as IIO reports temperature in mC
		 */
		*val = TMP117_RESOLUTION_10UC / MICRODEGREE_PER_10MILLIDEGREE;
		*val2 = (TMP117_RESOLUTION_10UC %
					MICRODEGREE_PER_10MILLIDEGREE) * 100;

		return IIO_VAL_INT_PLUS_MICRO;

	default:
		return -EINVAL;
	}
}

static int tmp117_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec
			    const *channel, int val, int val2, long mask)
{
	struct tmp117_data *data = iio_priv(indio_dev);
	s16 off;

	switch (mask) {
	case IIO_CHAN_INFO_CALIBBIAS:
		off = clamp_t(int, val, S16_MIN, S16_MAX);
		if (off == data->calibbias)
			return 0;
		data->calibbias = off;
		return i2c_smbus_write_word_swapped(data->client,
						TMP117_REG_TEMP_OFFSET, off);

	default:
		return -EINVAL;
	}
}

static const struct iio_chan_spec tmp117_channels[] = {
	{
		.type = IIO_TEMP,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
				      BIT(IIO_CHAN_INFO_CALIBBIAS) |
				      BIT(IIO_CHAN_INFO_SCALE),
	},
};

static const struct iio_chan_spec tmp116_channels[] = {
	{
		.type = IIO_TEMP,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
				      BIT(IIO_CHAN_INFO_SCALE),
	},
};

static const struct tmp11x_info tmp116_channels_info = {
	.name = "tmp116",
	.channels = tmp116_channels,
	.num_channels = ARRAY_SIZE(tmp116_channels)
};

static const struct tmp11x_info tmp117_channels_info = {
	.name = "tmp117",
	.channels = tmp117_channels,
	.num_channels = ARRAY_SIZE(tmp117_channels)
};

static const struct iio_info tmp117_info = {
	.read_raw = tmp117_read_raw,
	.write_raw = tmp117_write_raw,
};

static int tmp117_probe(struct i2c_client *client)
{
	const struct tmp11x_info *match_data;
	struct tmp117_data *data;
	struct iio_dev *indio_dev;
	int dev_id;
	int ret;

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

	ret = devm_regulator_get_enable(&client->dev, "vcc");
	if (ret)
		return ret;

	fsleep(1500);

	dev_id = i2c_smbus_read_word_swapped(client, TMP117_REG_DEVICE_ID);
	if (dev_id < 0)
		return dev_id;

	switch (dev_id) {
	case TMP116_DEVICE_ID:
		match_data = &tmp116_channels_info;
		break;
	case TMP117_DEVICE_ID:
		match_data = &tmp117_channels_info;
		break;
	default:
		dev_info(&client->dev,
			 "Unknown device id (0x%x), use fallback compatible\n",
			 dev_id);
		match_data = i2c_get_match_data(client);
	}

	if (!match_data)
		return dev_err_probe(&client->dev, -ENODEV,
				     "Failed to identify unsupported device\n");

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

	data = iio_priv(indio_dev);
	data->client = client;
	data->calibbias = 0;

	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->info = &tmp117_info;
	indio_dev->channels = match_data->channels;
	indio_dev->num_channels = match_data->num_channels;
	indio_dev->name = match_data->name;


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

static const struct of_device_id tmp117_of_match[] = {
	{ .compatible = "ti,tmp116", .data = &tmp116_channels_info },
	{ .compatible = "ti,tmp117", .data = &tmp117_channels_info },
	{ }
};
MODULE_DEVICE_TABLE(of, tmp117_of_match);

static const struct i2c_device_id tmp117_id[] = {
	{ "tmp116", (kernel_ulong_t)&tmp116_channels_info },
	{ "tmp117", (kernel_ulong_t)&tmp117_channels_info },
	{ }
};
MODULE_DEVICE_TABLE(i2c, tmp117_id);

static struct i2c_driver tmp117_driver = {
	.driver = {
		.name	= "tmp117",
		.of_match_table = tmp117_of_match,
	},
	.probe		= tmp117_probe,
	.id_table	= tmp117_id,
};
module_i2c_driver(tmp117_driver);

MODULE_AUTHOR("Puranjay Mohan <puranjay12@gmail.com>");
MODULE_DESCRIPTION("TI TMP117 Temperature sensor driver");
MODULE_LICENSE("GPL");