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