1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * tmp006.c - Support for TI TMP006 IR thermopile sensor
4 *
5 * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>
6 *
7 * Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
8 *
9 * (7-bit I2C slave address 0x40, changeable via ADR pins)
10 *
11 * TODO: data ready irq
12 */
13
14 #include <linux/err.h>
15 #include <linux/i2c.h>
16 #include <linux/delay.h>
17 #include <linux/module.h>
18 #include <linux/pm.h>
19 #include <linux/bitops.h>
20
21 #include <linux/iio/iio.h>
22 #include <linux/iio/sysfs.h>
23
24 #define TMP006_VOBJECT 0x00
25 #define TMP006_TAMBIENT 0x01
26 #define TMP006_CONFIG 0x02
27 #define TMP006_MANUFACTURER_ID 0xfe
28 #define TMP006_DEVICE_ID 0xff
29
30 #define TMP006_TAMBIENT_SHIFT 2
31
32 #define TMP006_CONFIG_RESET BIT(15)
33 #define TMP006_CONFIG_DRDY_EN BIT(8)
34 #define TMP006_CONFIG_DRDY BIT(7)
35
36 #define TMP006_CONFIG_MOD_MASK GENMASK(14, 12)
37
38 #define TMP006_CONFIG_CR_MASK GENMASK(11, 9)
39 #define TMP006_CONFIG_CR_SHIFT 9
40
41 #define TMP006_MANUFACTURER_MAGIC 0x5449
42 #define TMP006_DEVICE_MAGIC 0x0067
43
44 struct tmp006_data {
45 struct i2c_client *client;
46 u16 config;
47 };
48
tmp006_read_measurement(struct tmp006_data * data,u8 reg)49 static int tmp006_read_measurement(struct tmp006_data *data, u8 reg)
50 {
51 s32 ret;
52 int tries = 50;
53
54 while (tries-- > 0) {
55 ret = i2c_smbus_read_word_swapped(data->client,
56 TMP006_CONFIG);
57 if (ret < 0)
58 return ret;
59 if (ret & TMP006_CONFIG_DRDY)
60 break;
61 msleep(100);
62 }
63
64 if (tries < 0)
65 return -EIO;
66
67 return i2c_smbus_read_word_swapped(data->client, reg);
68 }
69
70 static const int tmp006_freqs[5][2] = { {4, 0}, {2, 0}, {1, 0},
71 {0, 500000}, {0, 250000} };
72
tmp006_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * channel,int * val,int * val2,long mask)73 static int tmp006_read_raw(struct iio_dev *indio_dev,
74 struct iio_chan_spec const *channel, int *val,
75 int *val2, long mask)
76 {
77 struct tmp006_data *data = iio_priv(indio_dev);
78 s32 ret;
79 int cr;
80
81 switch (mask) {
82 case IIO_CHAN_INFO_RAW:
83 if (channel->type == IIO_VOLTAGE) {
84 /* LSB is 156.25 nV */
85 ret = tmp006_read_measurement(data, TMP006_VOBJECT);
86 if (ret < 0)
87 return ret;
88 *val = sign_extend32(ret, 15);
89 } else if (channel->type == IIO_TEMP) {
90 /* LSB is 0.03125 degrees Celsius */
91 ret = tmp006_read_measurement(data, TMP006_TAMBIENT);
92 if (ret < 0)
93 return ret;
94 *val = sign_extend32(ret, 15) >> TMP006_TAMBIENT_SHIFT;
95 } else {
96 break;
97 }
98 return IIO_VAL_INT;
99 case IIO_CHAN_INFO_SCALE:
100 if (channel->type == IIO_VOLTAGE) {
101 *val = 0;
102 *val2 = 156250;
103 } else if (channel->type == IIO_TEMP) {
104 *val = 31;
105 *val2 = 250000;
106 } else {
107 break;
108 }
109 return IIO_VAL_INT_PLUS_MICRO;
110 case IIO_CHAN_INFO_SAMP_FREQ:
111 cr = (data->config & TMP006_CONFIG_CR_MASK)
112 >> TMP006_CONFIG_CR_SHIFT;
113 *val = tmp006_freqs[cr][0];
114 *val2 = tmp006_freqs[cr][1];
115 return IIO_VAL_INT_PLUS_MICRO;
116 default:
117 break;
118 }
119
120 return -EINVAL;
121 }
122
tmp006_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)123 static int tmp006_write_raw(struct iio_dev *indio_dev,
124 struct iio_chan_spec const *chan,
125 int val,
126 int val2,
127 long mask)
128 {
129 struct tmp006_data *data = iio_priv(indio_dev);
130 int i;
131
132 if (mask != IIO_CHAN_INFO_SAMP_FREQ)
133 return -EINVAL;
134
135 for (i = 0; i < ARRAY_SIZE(tmp006_freqs); i++)
136 if ((val == tmp006_freqs[i][0]) &&
137 (val2 == tmp006_freqs[i][1])) {
138 data->config &= ~TMP006_CONFIG_CR_MASK;
139 data->config |= i << TMP006_CONFIG_CR_SHIFT;
140
141 return i2c_smbus_write_word_swapped(data->client,
142 TMP006_CONFIG,
143 data->config);
144
145 }
146 return -EINVAL;
147 }
148
149 static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");
150
151 static struct attribute *tmp006_attributes[] = {
152 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
153 NULL
154 };
155
156 static const struct attribute_group tmp006_attribute_group = {
157 .attrs = tmp006_attributes,
158 };
159
160 static const struct iio_chan_spec tmp006_channels[] = {
161 {
162 .type = IIO_VOLTAGE,
163 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
164 BIT(IIO_CHAN_INFO_SCALE),
165 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
166 },
167 {
168 .type = IIO_TEMP,
169 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
170 BIT(IIO_CHAN_INFO_SCALE),
171 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
172 }
173 };
174
175 static const struct iio_info tmp006_info = {
176 .read_raw = tmp006_read_raw,
177 .write_raw = tmp006_write_raw,
178 .attrs = &tmp006_attribute_group,
179 };
180
tmp006_check_identification(struct i2c_client * client)181 static bool tmp006_check_identification(struct i2c_client *client)
182 {
183 int mid, did;
184
185 mid = i2c_smbus_read_word_swapped(client, TMP006_MANUFACTURER_ID);
186 if (mid < 0)
187 return false;
188
189 did = i2c_smbus_read_word_swapped(client, TMP006_DEVICE_ID);
190 if (did < 0)
191 return false;
192
193 return mid == TMP006_MANUFACTURER_MAGIC && did == TMP006_DEVICE_MAGIC;
194 }
195
tmp006_power(struct device * dev,bool up)196 static int tmp006_power(struct device *dev, bool up)
197 {
198 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
199 struct tmp006_data *data = iio_priv(indio_dev);
200
201 if (up)
202 data->config |= TMP006_CONFIG_MOD_MASK;
203 else
204 data->config &= ~TMP006_CONFIG_MOD_MASK;
205
206 return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
207 data->config);
208 }
209
tmp006_powerdown_cleanup(void * dev)210 static void tmp006_powerdown_cleanup(void *dev)
211 {
212 tmp006_power(dev, false);
213 }
214
tmp006_probe(struct i2c_client * client)215 static int tmp006_probe(struct i2c_client *client)
216 {
217 struct iio_dev *indio_dev;
218 struct tmp006_data *data;
219 int ret;
220
221 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
222 return -EOPNOTSUPP;
223
224 if (!tmp006_check_identification(client)) {
225 dev_err(&client->dev, "no TMP006 sensor\n");
226 return -ENODEV;
227 }
228
229 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
230 if (!indio_dev)
231 return -ENOMEM;
232
233 data = iio_priv(indio_dev);
234 i2c_set_clientdata(client, indio_dev);
235 data->client = client;
236
237 indio_dev->name = dev_name(&client->dev);
238 indio_dev->modes = INDIO_DIRECT_MODE;
239 indio_dev->info = &tmp006_info;
240
241 indio_dev->channels = tmp006_channels;
242 indio_dev->num_channels = ARRAY_SIZE(tmp006_channels);
243
244 ret = i2c_smbus_read_word_swapped(data->client, TMP006_CONFIG);
245 if (ret < 0)
246 return ret;
247 data->config = ret;
248
249 if ((ret & TMP006_CONFIG_MOD_MASK) != TMP006_CONFIG_MOD_MASK) {
250 ret = tmp006_power(&client->dev, true);
251 if (ret < 0)
252 return ret;
253 }
254
255 ret = devm_add_action_or_reset(&client->dev, tmp006_powerdown_cleanup,
256 &client->dev);
257 if (ret < 0)
258 return ret;
259
260 return devm_iio_device_register(&client->dev, indio_dev);
261 }
262
tmp006_suspend(struct device * dev)263 static int tmp006_suspend(struct device *dev)
264 {
265 return tmp006_power(dev, false);
266 }
267
tmp006_resume(struct device * dev)268 static int tmp006_resume(struct device *dev)
269 {
270 return tmp006_power(dev, true);
271 }
272
273 static DEFINE_SIMPLE_DEV_PM_OPS(tmp006_pm_ops, tmp006_suspend, tmp006_resume);
274
275 static const struct i2c_device_id tmp006_id[] = {
276 { "tmp006", 0 },
277 { }
278 };
279 MODULE_DEVICE_TABLE(i2c, tmp006_id);
280
281 static struct i2c_driver tmp006_driver = {
282 .driver = {
283 .name = "tmp006",
284 .pm = pm_sleep_ptr(&tmp006_pm_ops),
285 },
286 .probe_new = tmp006_probe,
287 .id_table = tmp006_id,
288 };
289 module_i2c_driver(tmp006_driver);
290
291 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
292 MODULE_DESCRIPTION("TI TMP006 IR thermopile sensor driver");
293 MODULE_LICENSE("GPL");
294