1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * hdc100x.c - Support for the TI HDC100x temperature + humidity sensors
4 *
5 * Copyright (C) 2015, 2018
6 * Author: Matt Ranostay <matt.ranostay@konsulko.com>
7 *
8 * Datasheets:
9 * http://www.ti.com/product/HDC1000/datasheet
10 * http://www.ti.com/product/HDC1008/datasheet
11 * http://www.ti.com/product/HDC1010/datasheet
12 * http://www.ti.com/product/HDC1050/datasheet
13 * http://www.ti.com/product/HDC1080/datasheet
14 */
15
16 #include <linux/delay.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/i2c.h>
20
21 #include <linux/iio/iio.h>
22 #include <linux/iio/sysfs.h>
23 #include <linux/iio/buffer.h>
24 #include <linux/iio/trigger_consumer.h>
25 #include <linux/iio/triggered_buffer.h>
26
27 #include <linux/time.h>
28
29 #define HDC100X_REG_TEMP 0x00
30 #define HDC100X_REG_HUMIDITY 0x01
31
32 #define HDC100X_REG_CONFIG 0x02
33 #define HDC100X_REG_CONFIG_ACQ_MODE BIT(12)
34 #define HDC100X_REG_CONFIG_HEATER_EN BIT(13)
35
36 struct hdc100x_data {
37 struct i2c_client *client;
38 struct mutex lock;
39 u16 config;
40
41 /* integration time of the sensor */
42 int adc_int_us[2];
43 /* Ensure natural alignment of timestamp */
44 struct {
45 __be16 channels[2];
46 s64 ts __aligned(8);
47 } scan;
48 };
49
50 /* integration time in us */
51 static const int hdc100x_int_time[][3] = {
52 { 6350, 3650, 0 }, /* IIO_TEMP channel*/
53 { 6500, 3850, 2500 }, /* IIO_HUMIDITYRELATIVE channel */
54 };
55
56 /* HDC100X_REG_CONFIG shift and mask values */
57 static const struct {
58 int shift;
59 int mask;
60 } hdc100x_resolution_shift[2] = {
61 { /* IIO_TEMP channel */
62 .shift = 10,
63 .mask = 1
64 },
65 { /* IIO_HUMIDITYRELATIVE channel */
66 .shift = 8,
67 .mask = 3,
68 },
69 };
70
71 static IIO_CONST_ATTR(temp_integration_time_available,
72 "0.00365 0.00635");
73
74 static IIO_CONST_ATTR(humidityrelative_integration_time_available,
75 "0.0025 0.00385 0.0065");
76
77 static IIO_CONST_ATTR(out_current_heater_raw_available,
78 "0 1");
79
80 static struct attribute *hdc100x_attributes[] = {
81 &iio_const_attr_temp_integration_time_available.dev_attr.attr,
82 &iio_const_attr_humidityrelative_integration_time_available.dev_attr.attr,
83 &iio_const_attr_out_current_heater_raw_available.dev_attr.attr,
84 NULL
85 };
86
87 static const struct attribute_group hdc100x_attribute_group = {
88 .attrs = hdc100x_attributes,
89 };
90
91 static const struct iio_chan_spec hdc100x_channels[] = {
92 {
93 .type = IIO_TEMP,
94 .address = HDC100X_REG_TEMP,
95 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
96 BIT(IIO_CHAN_INFO_SCALE) |
97 BIT(IIO_CHAN_INFO_INT_TIME) |
98 BIT(IIO_CHAN_INFO_OFFSET),
99 .scan_index = 0,
100 .scan_type = {
101 .sign = 's',
102 .realbits = 16,
103 .storagebits = 16,
104 .endianness = IIO_BE,
105 },
106 },
107 {
108 .type = IIO_HUMIDITYRELATIVE,
109 .address = HDC100X_REG_HUMIDITY,
110 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
111 BIT(IIO_CHAN_INFO_SCALE) |
112 BIT(IIO_CHAN_INFO_INT_TIME),
113 .scan_index = 1,
114 .scan_type = {
115 .sign = 'u',
116 .realbits = 16,
117 .storagebits = 16,
118 .endianness = IIO_BE,
119 },
120 },
121 {
122 .type = IIO_CURRENT,
123 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
124 .extend_name = "heater",
125 .output = 1,
126 .scan_index = -1,
127 },
128 IIO_CHAN_SOFT_TIMESTAMP(2),
129 };
130
131 static const unsigned long hdc100x_scan_masks[] = {0x3, 0};
132
hdc100x_update_config(struct hdc100x_data * data,int mask,int val)133 static int hdc100x_update_config(struct hdc100x_data *data, int mask, int val)
134 {
135 int tmp = (~mask & data->config) | val;
136 int ret;
137
138 ret = i2c_smbus_write_word_swapped(data->client,
139 HDC100X_REG_CONFIG, tmp);
140 if (!ret)
141 data->config = tmp;
142
143 return ret;
144 }
145
hdc100x_set_it_time(struct hdc100x_data * data,int chan,int val2)146 static int hdc100x_set_it_time(struct hdc100x_data *data, int chan, int val2)
147 {
148 int shift = hdc100x_resolution_shift[chan].shift;
149 int ret = -EINVAL;
150 int i;
151
152 for (i = 0; i < ARRAY_SIZE(hdc100x_int_time[chan]); i++) {
153 if (val2 && val2 == hdc100x_int_time[chan][i]) {
154 ret = hdc100x_update_config(data,
155 hdc100x_resolution_shift[chan].mask << shift,
156 i << shift);
157 if (!ret)
158 data->adc_int_us[chan] = val2;
159 break;
160 }
161 }
162
163 return ret;
164 }
165
hdc100x_get_measurement(struct hdc100x_data * data,struct iio_chan_spec const * chan)166 static int hdc100x_get_measurement(struct hdc100x_data *data,
167 struct iio_chan_spec const *chan)
168 {
169 struct i2c_client *client = data->client;
170 int delay = data->adc_int_us[chan->address] + 1*USEC_PER_MSEC;
171 int ret;
172 __be16 val;
173
174 /* start measurement */
175 ret = i2c_smbus_write_byte(client, chan->address);
176 if (ret < 0) {
177 dev_err(&client->dev, "cannot start measurement");
178 return ret;
179 }
180
181 /* wait for integration time to pass */
182 usleep_range(delay, delay + 1000);
183
184 /* read measurement */
185 ret = i2c_master_recv(data->client, (char *)&val, sizeof(val));
186 if (ret < 0) {
187 dev_err(&client->dev, "cannot read sensor data\n");
188 return ret;
189 }
190 return be16_to_cpu(val);
191 }
192
hdc100x_get_heater_status(struct hdc100x_data * data)193 static int hdc100x_get_heater_status(struct hdc100x_data *data)
194 {
195 return !!(data->config & HDC100X_REG_CONFIG_HEATER_EN);
196 }
197
hdc100x_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)198 static int hdc100x_read_raw(struct iio_dev *indio_dev,
199 struct iio_chan_spec const *chan, int *val,
200 int *val2, long mask)
201 {
202 struct hdc100x_data *data = iio_priv(indio_dev);
203
204 switch (mask) {
205 case IIO_CHAN_INFO_RAW: {
206 int ret;
207
208 mutex_lock(&data->lock);
209 if (chan->type == IIO_CURRENT) {
210 *val = hdc100x_get_heater_status(data);
211 ret = IIO_VAL_INT;
212 } else {
213 ret = iio_device_claim_direct_mode(indio_dev);
214 if (ret) {
215 mutex_unlock(&data->lock);
216 return ret;
217 }
218
219 ret = hdc100x_get_measurement(data, chan);
220 iio_device_release_direct_mode(indio_dev);
221 if (ret >= 0) {
222 *val = ret;
223 ret = IIO_VAL_INT;
224 }
225 }
226 mutex_unlock(&data->lock);
227 return ret;
228 }
229 case IIO_CHAN_INFO_INT_TIME:
230 *val = 0;
231 *val2 = data->adc_int_us[chan->address];
232 return IIO_VAL_INT_PLUS_MICRO;
233 case IIO_CHAN_INFO_SCALE:
234 if (chan->type == IIO_TEMP) {
235 *val = 165000;
236 *val2 = 65536;
237 return IIO_VAL_FRACTIONAL;
238 } else {
239 *val = 100000;
240 *val2 = 65536;
241 return IIO_VAL_FRACTIONAL;
242 }
243 break;
244 case IIO_CHAN_INFO_OFFSET:
245 *val = -15887;
246 *val2 = 515151;
247 return IIO_VAL_INT_PLUS_MICRO;
248 default:
249 return -EINVAL;
250 }
251 }
252
hdc100x_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)253 static int hdc100x_write_raw(struct iio_dev *indio_dev,
254 struct iio_chan_spec const *chan,
255 int val, int val2, long mask)
256 {
257 struct hdc100x_data *data = iio_priv(indio_dev);
258 int ret = -EINVAL;
259
260 switch (mask) {
261 case IIO_CHAN_INFO_INT_TIME:
262 if (val != 0)
263 return -EINVAL;
264
265 mutex_lock(&data->lock);
266 ret = hdc100x_set_it_time(data, chan->address, val2);
267 mutex_unlock(&data->lock);
268 return ret;
269 case IIO_CHAN_INFO_RAW:
270 if (chan->type != IIO_CURRENT || val2 != 0)
271 return -EINVAL;
272
273 mutex_lock(&data->lock);
274 ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_HEATER_EN,
275 val ? HDC100X_REG_CONFIG_HEATER_EN : 0);
276 mutex_unlock(&data->lock);
277 return ret;
278 default:
279 return -EINVAL;
280 }
281 }
282
hdc100x_buffer_postenable(struct iio_dev * indio_dev)283 static int hdc100x_buffer_postenable(struct iio_dev *indio_dev)
284 {
285 struct hdc100x_data *data = iio_priv(indio_dev);
286 int ret;
287
288 /* Buffer is enabled. First set ACQ Mode, then attach poll func */
289 mutex_lock(&data->lock);
290 ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE,
291 HDC100X_REG_CONFIG_ACQ_MODE);
292 mutex_unlock(&data->lock);
293 if (ret)
294 return ret;
295
296 return iio_triggered_buffer_postenable(indio_dev);
297 }
298
hdc100x_buffer_predisable(struct iio_dev * indio_dev)299 static int hdc100x_buffer_predisable(struct iio_dev *indio_dev)
300 {
301 struct hdc100x_data *data = iio_priv(indio_dev);
302 int ret;
303
304 /* First detach poll func, then reset ACQ mode. OK to disable buffer */
305 ret = iio_triggered_buffer_predisable(indio_dev);
306 if (ret)
307 return ret;
308
309 mutex_lock(&data->lock);
310 ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 0);
311 mutex_unlock(&data->lock);
312
313 return ret;
314 }
315
316 static const struct iio_buffer_setup_ops hdc_buffer_setup_ops = {
317 .postenable = hdc100x_buffer_postenable,
318 .predisable = hdc100x_buffer_predisable,
319 };
320
hdc100x_trigger_handler(int irq,void * p)321 static irqreturn_t hdc100x_trigger_handler(int irq, void *p)
322 {
323 struct iio_poll_func *pf = p;
324 struct iio_dev *indio_dev = pf->indio_dev;
325 struct hdc100x_data *data = iio_priv(indio_dev);
326 struct i2c_client *client = data->client;
327 int delay = data->adc_int_us[0] + data->adc_int_us[1] + 2*USEC_PER_MSEC;
328 int ret;
329
330 /* dual read starts at temp register */
331 mutex_lock(&data->lock);
332 ret = i2c_smbus_write_byte(client, HDC100X_REG_TEMP);
333 if (ret < 0) {
334 dev_err(&client->dev, "cannot start measurement\n");
335 goto err;
336 }
337 usleep_range(delay, delay + 1000);
338
339 ret = i2c_master_recv(client, (u8 *)data->scan.channels, 4);
340 if (ret < 0) {
341 dev_err(&client->dev, "cannot read sensor data\n");
342 goto err;
343 }
344
345 iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
346 iio_get_time_ns(indio_dev));
347 err:
348 mutex_unlock(&data->lock);
349 iio_trigger_notify_done(indio_dev->trig);
350
351 return IRQ_HANDLED;
352 }
353
354 static const struct iio_info hdc100x_info = {
355 .read_raw = hdc100x_read_raw,
356 .write_raw = hdc100x_write_raw,
357 .attrs = &hdc100x_attribute_group,
358 };
359
hdc100x_probe(struct i2c_client * client,const struct i2c_device_id * id)360 static int hdc100x_probe(struct i2c_client *client,
361 const struct i2c_device_id *id)
362 {
363 struct iio_dev *indio_dev;
364 struct hdc100x_data *data;
365 int ret;
366
367 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA |
368 I2C_FUNC_SMBUS_BYTE | I2C_FUNC_I2C))
369 return -EOPNOTSUPP;
370
371 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
372 if (!indio_dev)
373 return -ENOMEM;
374
375 data = iio_priv(indio_dev);
376 i2c_set_clientdata(client, indio_dev);
377 data->client = client;
378 mutex_init(&data->lock);
379
380 indio_dev->dev.parent = &client->dev;
381 indio_dev->name = dev_name(&client->dev);
382 indio_dev->modes = INDIO_DIRECT_MODE;
383 indio_dev->info = &hdc100x_info;
384
385 indio_dev->channels = hdc100x_channels;
386 indio_dev->num_channels = ARRAY_SIZE(hdc100x_channels);
387 indio_dev->available_scan_masks = hdc100x_scan_masks;
388
389 /* be sure we are in a known state */
390 hdc100x_set_it_time(data, 0, hdc100x_int_time[0][0]);
391 hdc100x_set_it_time(data, 1, hdc100x_int_time[1][0]);
392 hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 0);
393
394 ret = iio_triggered_buffer_setup(indio_dev, NULL,
395 hdc100x_trigger_handler,
396 &hdc_buffer_setup_ops);
397 if (ret < 0) {
398 dev_err(&client->dev, "iio triggered buffer setup failed\n");
399 return ret;
400 }
401 ret = iio_device_register(indio_dev);
402 if (ret < 0)
403 iio_triggered_buffer_cleanup(indio_dev);
404
405 return ret;
406 }
407
hdc100x_remove(struct i2c_client * client)408 static int hdc100x_remove(struct i2c_client *client)
409 {
410 struct iio_dev *indio_dev = i2c_get_clientdata(client);
411
412 iio_device_unregister(indio_dev);
413 iio_triggered_buffer_cleanup(indio_dev);
414
415 return 0;
416 }
417
418 static const struct i2c_device_id hdc100x_id[] = {
419 { "hdc100x", 0 },
420 { "hdc1000", 0 },
421 { "hdc1008", 0 },
422 { "hdc1010", 0 },
423 { "hdc1050", 0 },
424 { "hdc1080", 0 },
425 { }
426 };
427 MODULE_DEVICE_TABLE(i2c, hdc100x_id);
428
429 static const struct of_device_id hdc100x_dt_ids[] = {
430 { .compatible = "ti,hdc1000" },
431 { .compatible = "ti,hdc1008" },
432 { .compatible = "ti,hdc1010" },
433 { .compatible = "ti,hdc1050" },
434 { .compatible = "ti,hdc1080" },
435 { }
436 };
437 MODULE_DEVICE_TABLE(of, hdc100x_dt_ids);
438
439 static struct i2c_driver hdc100x_driver = {
440 .driver = {
441 .name = "hdc100x",
442 .of_match_table = of_match_ptr(hdc100x_dt_ids),
443 },
444 .probe = hdc100x_probe,
445 .remove = hdc100x_remove,
446 .id_table = hdc100x_id,
447 };
448 module_i2c_driver(hdc100x_driver);
449
450 MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");
451 MODULE_DESCRIPTION("TI HDC100x humidity and temperature sensor driver");
452 MODULE_LICENSE("GPL");
453