1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * hdc2010.c - Support for the TI HDC2010 and HDC2080
4 * temperature + relative humidity sensors
5 *
6 * Copyright (C) 2020 Norphonic AS
7 * Author: Eugene Zaikonnikov <ez@norphonic.com>
8 *
9 * Datasheet: https://www.ti.com/product/HDC2010/datasheet
10 * Datasheet: https://www.ti.com/product/HDC2080/datasheet
11 */
12
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/i2c.h>
16 #include <linux/bitops.h>
17
18 #include <linux/iio/iio.h>
19 #include <linux/iio/sysfs.h>
20
21 #define HDC2010_REG_TEMP_LOW 0x00
22 #define HDC2010_REG_TEMP_HIGH 0x01
23 #define HDC2010_REG_HUMIDITY_LOW 0x02
24 #define HDC2010_REG_HUMIDITY_HIGH 0x03
25 #define HDC2010_REG_INTERRUPT_DRDY 0x04
26 #define HDC2010_REG_TEMP_MAX 0x05
27 #define HDC2010_REG_HUMIDITY_MAX 0x06
28 #define HDC2010_REG_INTERRUPT_EN 0x07
29 #define HDC2010_REG_TEMP_OFFSET_ADJ 0x08
30 #define HDC2010_REG_HUMIDITY_OFFSET_ADJ 0x09
31 #define HDC2010_REG_TEMP_THR_L 0x0a
32 #define HDC2010_REG_TEMP_THR_H 0x0b
33 #define HDC2010_REG_RH_THR_L 0x0c
34 #define HDC2010_REG_RH_THR_H 0x0d
35 #define HDC2010_REG_RESET_DRDY_INT_CONF 0x0e
36 #define HDC2010_REG_MEASUREMENT_CONF 0x0f
37
38 #define HDC2010_MEAS_CONF GENMASK(2, 1)
39 #define HDC2010_MEAS_TRIG BIT(0)
40 #define HDC2010_HEATER_EN BIT(3)
41 #define HDC2010_AMM GENMASK(6, 4)
42
43 struct hdc2010_data {
44 struct i2c_client *client;
45 struct mutex lock;
46 u8 measurement_config;
47 u8 interrupt_config;
48 u8 drdy_config;
49 };
50
51 enum hdc2010_addr_groups {
52 HDC2010_GROUP_TEMP = 0,
53 HDC2010_GROUP_HUMIDITY,
54 };
55
56 struct hdc2010_reg_record {
57 unsigned long primary;
58 unsigned long peak;
59 };
60
61 static const struct hdc2010_reg_record hdc2010_reg_translation[] = {
62 [HDC2010_GROUP_TEMP] = {
63 .primary = HDC2010_REG_TEMP_LOW,
64 .peak = HDC2010_REG_TEMP_MAX,
65 },
66 [HDC2010_GROUP_HUMIDITY] = {
67 .primary = HDC2010_REG_HUMIDITY_LOW,
68 .peak = HDC2010_REG_HUMIDITY_MAX,
69 },
70 };
71
72 static IIO_CONST_ATTR(out_current_heater_raw_available, "0 1");
73
74 static struct attribute *hdc2010_attributes[] = {
75 &iio_const_attr_out_current_heater_raw_available.dev_attr.attr,
76 NULL
77 };
78
79 static const struct attribute_group hdc2010_attribute_group = {
80 .attrs = hdc2010_attributes,
81 };
82
83 static const struct iio_chan_spec hdc2010_channels[] = {
84 {
85 .type = IIO_TEMP,
86 .address = HDC2010_GROUP_TEMP,
87 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
88 BIT(IIO_CHAN_INFO_PEAK) |
89 BIT(IIO_CHAN_INFO_OFFSET) |
90 BIT(IIO_CHAN_INFO_SCALE),
91 },
92 {
93 .type = IIO_HUMIDITYRELATIVE,
94 .address = HDC2010_GROUP_HUMIDITY,
95 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
96 BIT(IIO_CHAN_INFO_PEAK) |
97 BIT(IIO_CHAN_INFO_SCALE),
98 },
99 {
100 .type = IIO_CURRENT,
101 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
102 .extend_name = "heater",
103 .output = 1,
104 },
105 };
106
hdc2010_update_drdy_config(struct hdc2010_data * data,char mask,char val)107 static int hdc2010_update_drdy_config(struct hdc2010_data *data,
108 char mask, char val)
109 {
110 u8 tmp = (~mask & data->drdy_config) | val;
111 int ret;
112
113 ret = i2c_smbus_write_byte_data(data->client,
114 HDC2010_REG_RESET_DRDY_INT_CONF, tmp);
115 if (ret)
116 return ret;
117
118 data->drdy_config = tmp;
119
120 return 0;
121 }
122
hdc2010_get_prim_measurement_word(struct hdc2010_data * data,struct iio_chan_spec const * chan)123 static int hdc2010_get_prim_measurement_word(struct hdc2010_data *data,
124 struct iio_chan_spec const *chan)
125 {
126 struct i2c_client *client = data->client;
127 s32 ret;
128
129 ret = i2c_smbus_read_word_data(client,
130 hdc2010_reg_translation[chan->address].primary);
131
132 if (ret < 0)
133 dev_err(&client->dev, "Could not read sensor measurement word\n");
134
135 return ret;
136 }
137
hdc2010_get_peak_measurement_byte(struct hdc2010_data * data,struct iio_chan_spec const * chan)138 static int hdc2010_get_peak_measurement_byte(struct hdc2010_data *data,
139 struct iio_chan_spec const *chan)
140 {
141 struct i2c_client *client = data->client;
142 s32 ret;
143
144 ret = i2c_smbus_read_byte_data(client,
145 hdc2010_reg_translation[chan->address].peak);
146
147 if (ret < 0)
148 dev_err(&client->dev, "Could not read sensor measurement byte\n");
149
150 return ret;
151 }
152
hdc2010_get_heater_status(struct hdc2010_data * data)153 static int hdc2010_get_heater_status(struct hdc2010_data *data)
154 {
155 return !!(data->drdy_config & HDC2010_HEATER_EN);
156 }
157
hdc2010_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)158 static int hdc2010_read_raw(struct iio_dev *indio_dev,
159 struct iio_chan_spec const *chan, int *val,
160 int *val2, long mask)
161 {
162 struct hdc2010_data *data = iio_priv(indio_dev);
163
164 switch (mask) {
165 case IIO_CHAN_INFO_RAW: {
166 int ret;
167
168 if (chan->type == IIO_CURRENT) {
169 *val = hdc2010_get_heater_status(data);
170 return IIO_VAL_INT;
171 }
172 ret = iio_device_claim_direct_mode(indio_dev);
173 if (ret)
174 return ret;
175 mutex_lock(&data->lock);
176 ret = hdc2010_get_prim_measurement_word(data, chan);
177 mutex_unlock(&data->lock);
178 iio_device_release_direct_mode(indio_dev);
179 if (ret < 0)
180 return ret;
181 *val = ret;
182 return IIO_VAL_INT;
183 }
184 case IIO_CHAN_INFO_PEAK: {
185 int ret;
186
187 ret = iio_device_claim_direct_mode(indio_dev);
188 if (ret)
189 return ret;
190 mutex_lock(&data->lock);
191 ret = hdc2010_get_peak_measurement_byte(data, chan);
192 mutex_unlock(&data->lock);
193 iio_device_release_direct_mode(indio_dev);
194 if (ret < 0)
195 return ret;
196 /* Scaling up the value so we can use same offset as RAW */
197 *val = ret * 256;
198 return IIO_VAL_INT;
199 }
200 case IIO_CHAN_INFO_SCALE:
201 *val2 = 65536;
202 if (chan->type == IIO_TEMP)
203 *val = 165000;
204 else
205 *val = 100000;
206 return IIO_VAL_FRACTIONAL;
207 case IIO_CHAN_INFO_OFFSET:
208 *val = -15887;
209 *val2 = 515151;
210 return IIO_VAL_INT_PLUS_MICRO;
211 default:
212 return -EINVAL;
213 }
214 }
215
hdc2010_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)216 static int hdc2010_write_raw(struct iio_dev *indio_dev,
217 struct iio_chan_spec const *chan,
218 int val, int val2, long mask)
219 {
220 struct hdc2010_data *data = iio_priv(indio_dev);
221 int new, ret;
222
223 switch (mask) {
224 case IIO_CHAN_INFO_RAW:
225 if (chan->type != IIO_CURRENT || val2 != 0)
226 return -EINVAL;
227
228 switch (val) {
229 case 1:
230 new = HDC2010_HEATER_EN;
231 break;
232 case 0:
233 new = 0;
234 break;
235 default:
236 return -EINVAL;
237 }
238
239 mutex_lock(&data->lock);
240 ret = hdc2010_update_drdy_config(data, HDC2010_HEATER_EN, new);
241 mutex_unlock(&data->lock);
242 return ret;
243 default:
244 return -EINVAL;
245 }
246 }
247
248 static const struct iio_info hdc2010_info = {
249 .read_raw = hdc2010_read_raw,
250 .write_raw = hdc2010_write_raw,
251 .attrs = &hdc2010_attribute_group,
252 };
253
hdc2010_probe(struct i2c_client * client)254 static int hdc2010_probe(struct i2c_client *client)
255 {
256 struct iio_dev *indio_dev;
257 struct hdc2010_data *data;
258 u8 tmp;
259 int ret;
260
261 if (!i2c_check_functionality(client->adapter,
262 I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_I2C))
263 return -EOPNOTSUPP;
264
265 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
266 if (!indio_dev)
267 return -ENOMEM;
268
269 data = iio_priv(indio_dev);
270 i2c_set_clientdata(client, indio_dev);
271 data->client = client;
272 mutex_init(&data->lock);
273
274 /*
275 * As DEVICE ID register does not differentiate between
276 * HDC2010 and HDC2080, we have the name hardcoded
277 */
278 indio_dev->name = "hdc2010";
279 indio_dev->modes = INDIO_DIRECT_MODE;
280 indio_dev->info = &hdc2010_info;
281
282 indio_dev->channels = hdc2010_channels;
283 indio_dev->num_channels = ARRAY_SIZE(hdc2010_channels);
284
285 /* Enable Automatic Measurement Mode at 5Hz */
286 ret = hdc2010_update_drdy_config(data, HDC2010_AMM, HDC2010_AMM);
287 if (ret)
288 return ret;
289
290 /*
291 * We enable both temp and humidity measurement.
292 * However the measurement won't start even in AMM until triggered.
293 */
294 tmp = (data->measurement_config & ~HDC2010_MEAS_CONF) |
295 HDC2010_MEAS_TRIG;
296
297 ret = i2c_smbus_write_byte_data(client, HDC2010_REG_MEASUREMENT_CONF, tmp);
298 if (ret) {
299 dev_warn(&client->dev, "Unable to set up measurement\n");
300 if (hdc2010_update_drdy_config(data, HDC2010_AMM, 0))
301 dev_warn(&client->dev, "Unable to restore default AMM\n");
302 return ret;
303 }
304
305 data->measurement_config = tmp;
306
307 return iio_device_register(indio_dev);
308 }
309
hdc2010_remove(struct i2c_client * client)310 static void hdc2010_remove(struct i2c_client *client)
311 {
312 struct iio_dev *indio_dev = i2c_get_clientdata(client);
313 struct hdc2010_data *data = iio_priv(indio_dev);
314
315 iio_device_unregister(indio_dev);
316
317 /* Disable Automatic Measurement Mode */
318 if (hdc2010_update_drdy_config(data, HDC2010_AMM, 0))
319 dev_warn(&client->dev, "Unable to restore default AMM\n");
320 }
321
322 static const struct i2c_device_id hdc2010_id[] = {
323 { "hdc2010" },
324 { "hdc2080" },
325 { }
326 };
327 MODULE_DEVICE_TABLE(i2c, hdc2010_id);
328
329 static const struct of_device_id hdc2010_dt_ids[] = {
330 { .compatible = "ti,hdc2010" },
331 { .compatible = "ti,hdc2080" },
332 { }
333 };
334 MODULE_DEVICE_TABLE(of, hdc2010_dt_ids);
335
336 static struct i2c_driver hdc2010_driver = {
337 .driver = {
338 .name = "hdc2010",
339 .of_match_table = hdc2010_dt_ids,
340 },
341 .probe = hdc2010_probe,
342 .remove = hdc2010_remove,
343 .id_table = hdc2010_id,
344 };
345 module_i2c_driver(hdc2010_driver);
346
347 MODULE_AUTHOR("Eugene Zaikonnikov <ez@norphonic.com>");
348 MODULE_DESCRIPTION("TI HDC2010 humidity and temperature sensor driver");
349 MODULE_LICENSE("GPL");
350