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/mod_devicetable.h>
19 #include <linux/pm.h>
20 #include <linux/bitops.h>
21
22 #include <linux/iio/iio.h>
23 #include <linux/iio/sysfs.h>
24
25 #define TMP006_VOBJECT 0x00
26 #define TMP006_TAMBIENT 0x01
27 #define TMP006_CONFIG 0x02
28 #define TMP006_MANUFACTURER_ID 0xfe
29 #define TMP006_DEVICE_ID 0xff
30
31 #define TMP006_TAMBIENT_SHIFT 2
32
33 #define TMP006_CONFIG_RESET BIT(15)
34 #define TMP006_CONFIG_DRDY_EN BIT(8)
35 #define TMP006_CONFIG_DRDY BIT(7)
36
37 #define TMP006_CONFIG_MOD_MASK GENMASK(14, 12)
38
39 #define TMP006_CONFIG_CR_MASK GENMASK(11, 9)
40 #define TMP006_CONFIG_CR_SHIFT 9
41
42 #define TMP006_MANUFACTURER_MAGIC 0x5449
43 #define TMP006_DEVICE_MAGIC 0x0067
44
45 struct tmp006_data {
46 struct i2c_client *client;
47 u16 config;
48 };
49
tmp006_read_measurement(struct tmp006_data * data,u8 reg)50 static int tmp006_read_measurement(struct tmp006_data *data, u8 reg)
51 {
52 s32 ret;
53 int tries = 50;
54
55 while (tries-- > 0) {
56 ret = i2c_smbus_read_word_swapped(data->client,
57 TMP006_CONFIG);
58 if (ret < 0)
59 return ret;
60 if (ret & TMP006_CONFIG_DRDY)
61 break;
62 msleep(100);
63 }
64
65 if (tries < 0)
66 return -EIO;
67
68 return i2c_smbus_read_word_swapped(data->client, reg);
69 }
70
71 static const int tmp006_freqs[5][2] = { {4, 0}, {2, 0}, {1, 0},
72 {0, 500000}, {0, 250000} };
73
tmp006_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * channel,int * val,int * val2,long mask)74 static int tmp006_read_raw(struct iio_dev *indio_dev,
75 struct iio_chan_spec const *channel, int *val,
76 int *val2, long mask)
77 {
78 struct tmp006_data *data = iio_priv(indio_dev);
79 s32 ret;
80 int cr;
81
82 switch (mask) {
83 case IIO_CHAN_INFO_RAW:
84 if (channel->type == IIO_VOLTAGE) {
85 /* LSB is 156.25 nV */
86 ret = tmp006_read_measurement(data, TMP006_VOBJECT);
87 if (ret < 0)
88 return ret;
89 *val = sign_extend32(ret, 15);
90 } else if (channel->type == IIO_TEMP) {
91 /* LSB is 0.03125 degrees Celsius */
92 ret = tmp006_read_measurement(data, TMP006_TAMBIENT);
93 if (ret < 0)
94 return ret;
95 *val = sign_extend32(ret, 15) >> TMP006_TAMBIENT_SHIFT;
96 } else {
97 break;
98 }
99 return IIO_VAL_INT;
100 case IIO_CHAN_INFO_SCALE:
101 if (channel->type == IIO_VOLTAGE) {
102 *val = 0;
103 *val2 = 156250;
104 } else if (channel->type == IIO_TEMP) {
105 *val = 31;
106 *val2 = 250000;
107 } else {
108 break;
109 }
110 return IIO_VAL_INT_PLUS_MICRO;
111 case IIO_CHAN_INFO_SAMP_FREQ:
112 cr = (data->config & TMP006_CONFIG_CR_MASK)
113 >> TMP006_CONFIG_CR_SHIFT;
114 *val = tmp006_freqs[cr][0];
115 *val2 = tmp006_freqs[cr][1];
116 return IIO_VAL_INT_PLUS_MICRO;
117 default:
118 break;
119 }
120
121 return -EINVAL;
122 }
123
tmp006_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)124 static int tmp006_write_raw(struct iio_dev *indio_dev,
125 struct iio_chan_spec const *chan,
126 int val,
127 int val2,
128 long mask)
129 {
130 struct tmp006_data *data = iio_priv(indio_dev);
131 int i;
132
133 if (mask != IIO_CHAN_INFO_SAMP_FREQ)
134 return -EINVAL;
135
136 for (i = 0; i < ARRAY_SIZE(tmp006_freqs); i++)
137 if ((val == tmp006_freqs[i][0]) &&
138 (val2 == tmp006_freqs[i][1])) {
139 data->config &= ~TMP006_CONFIG_CR_MASK;
140 data->config |= i << TMP006_CONFIG_CR_SHIFT;
141
142 return i2c_smbus_write_word_swapped(data->client,
143 TMP006_CONFIG,
144 data->config);
145
146 }
147 return -EINVAL;
148 }
149
150 static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");
151
152 static struct attribute *tmp006_attributes[] = {
153 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
154 NULL
155 };
156
157 static const struct attribute_group tmp006_attribute_group = {
158 .attrs = tmp006_attributes,
159 };
160
161 static const struct iio_chan_spec tmp006_channels[] = {
162 {
163 .type = IIO_VOLTAGE,
164 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
165 BIT(IIO_CHAN_INFO_SCALE),
166 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
167 },
168 {
169 .type = IIO_TEMP,
170 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
171 BIT(IIO_CHAN_INFO_SCALE),
172 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
173 }
174 };
175
176 static const struct iio_info tmp006_info = {
177 .read_raw = tmp006_read_raw,
178 .write_raw = tmp006_write_raw,
179 .attrs = &tmp006_attribute_group,
180 };
181
tmp006_check_identification(struct i2c_client * client)182 static bool tmp006_check_identification(struct i2c_client *client)
183 {
184 int mid, did;
185
186 mid = i2c_smbus_read_word_swapped(client, TMP006_MANUFACTURER_ID);
187 if (mid < 0)
188 return false;
189
190 did = i2c_smbus_read_word_swapped(client, TMP006_DEVICE_ID);
191 if (did < 0)
192 return false;
193
194 return mid == TMP006_MANUFACTURER_MAGIC && did == TMP006_DEVICE_MAGIC;
195 }
196
tmp006_power(struct device * dev,bool up)197 static int tmp006_power(struct device *dev, bool up)
198 {
199 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
200 struct tmp006_data *data = iio_priv(indio_dev);
201
202 if (up)
203 data->config |= TMP006_CONFIG_MOD_MASK;
204 else
205 data->config &= ~TMP006_CONFIG_MOD_MASK;
206
207 return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
208 data->config);
209 }
210
tmp006_powerdown_cleanup(void * dev)211 static void tmp006_powerdown_cleanup(void *dev)
212 {
213 tmp006_power(dev, false);
214 }
215
tmp006_probe(struct i2c_client * client)216 static int tmp006_probe(struct i2c_client *client)
217 {
218 struct iio_dev *indio_dev;
219 struct tmp006_data *data;
220 int ret;
221
222 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
223 return -EOPNOTSUPP;
224
225 if (!tmp006_check_identification(client)) {
226 dev_err(&client->dev, "no TMP006 sensor\n");
227 return -ENODEV;
228 }
229
230 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
231 if (!indio_dev)
232 return -ENOMEM;
233
234 data = iio_priv(indio_dev);
235 i2c_set_clientdata(client, indio_dev);
236 data->client = client;
237
238 indio_dev->name = dev_name(&client->dev);
239 indio_dev->modes = INDIO_DIRECT_MODE;
240 indio_dev->info = &tmp006_info;
241
242 indio_dev->channels = tmp006_channels;
243 indio_dev->num_channels = ARRAY_SIZE(tmp006_channels);
244
245 ret = i2c_smbus_read_word_swapped(data->client, TMP006_CONFIG);
246 if (ret < 0)
247 return ret;
248 data->config = ret;
249
250 if ((ret & TMP006_CONFIG_MOD_MASK) != TMP006_CONFIG_MOD_MASK) {
251 ret = tmp006_power(&client->dev, true);
252 if (ret < 0)
253 return ret;
254 }
255
256 ret = devm_add_action_or_reset(&client->dev, tmp006_powerdown_cleanup,
257 &client->dev);
258 if (ret < 0)
259 return ret;
260
261 return devm_iio_device_register(&client->dev, indio_dev);
262 }
263
tmp006_suspend(struct device * dev)264 static int tmp006_suspend(struct device *dev)
265 {
266 return tmp006_power(dev, false);
267 }
268
tmp006_resume(struct device * dev)269 static int tmp006_resume(struct device *dev)
270 {
271 return tmp006_power(dev, true);
272 }
273
274 static DEFINE_SIMPLE_DEV_PM_OPS(tmp006_pm_ops, tmp006_suspend, tmp006_resume);
275
276 static const struct of_device_id tmp006_of_match[] = {
277 { .compatible = "ti,tmp006" },
278 { }
279 };
280 MODULE_DEVICE_TABLE(of, tmp006_of_match);
281
282 static const struct i2c_device_id tmp006_id[] = {
283 { "tmp006", 0 },
284 { }
285 };
286 MODULE_DEVICE_TABLE(i2c, tmp006_id);
287
288 static struct i2c_driver tmp006_driver = {
289 .driver = {
290 .name = "tmp006",
291 .of_match_table = tmp006_of_match,
292 .pm = pm_sleep_ptr(&tmp006_pm_ops),
293 },
294 .probe = tmp006_probe,
295 .id_table = tmp006_id,
296 };
297 module_i2c_driver(tmp006_driver);
298
299 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
300 MODULE_DESCRIPTION("TI TMP006 IR thermopile sensor driver");
301 MODULE_LICENSE("GPL");
302