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18#include <linux/delay.h>
19#include <linux/module.h>
20#include <linux/init.h>
21#include <linux/i2c.h>
22
23#include <linux/iio/iio.h>
24#include <linux/iio/sysfs.h>
25
26#define HDC100X_REG_TEMP 0x00
27#define HDC100X_REG_HUMIDITY 0x01
28
29#define HDC100X_REG_CONFIG 0x02
30#define HDC100X_REG_CONFIG_HEATER_EN BIT(13)
31
32struct hdc100x_data {
33 struct i2c_client *client;
34 struct mutex lock;
35 u16 config;
36
37
38 int adc_int_us[2];
39};
40
41
42static const int hdc100x_int_time[][3] = {
43 { 6350, 3650, 0 },
44 { 6500, 3850, 2500 },
45};
46
47
48static const struct {
49 int shift;
50 int mask;
51} hdc100x_resolution_shift[2] = {
52 {
53 .shift = 10,
54 .mask = 1
55 },
56 {
57 .shift = 8,
58 .mask = 3,
59 },
60};
61
62static IIO_CONST_ATTR(temp_integration_time_available,
63 "0.00365 0.00635");
64
65static IIO_CONST_ATTR(humidityrelative_integration_time_available,
66 "0.0025 0.00385 0.0065");
67
68static IIO_CONST_ATTR(out_current_heater_raw_available,
69 "0 1");
70
71static struct attribute *hdc100x_attributes[] = {
72 &iio_const_attr_temp_integration_time_available.dev_attr.attr,
73 &iio_const_attr_humidityrelative_integration_time_available.dev_attr.attr,
74 &iio_const_attr_out_current_heater_raw_available.dev_attr.attr,
75 NULL
76};
77
78static struct attribute_group hdc100x_attribute_group = {
79 .attrs = hdc100x_attributes,
80};
81
82static const struct iio_chan_spec hdc100x_channels[] = {
83 {
84 .type = IIO_TEMP,
85 .address = HDC100X_REG_TEMP,
86 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
87 BIT(IIO_CHAN_INFO_SCALE) |
88 BIT(IIO_CHAN_INFO_INT_TIME) |
89 BIT(IIO_CHAN_INFO_OFFSET),
90 },
91 {
92 .type = IIO_HUMIDITYRELATIVE,
93 .address = HDC100X_REG_HUMIDITY,
94 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
95 BIT(IIO_CHAN_INFO_SCALE) |
96 BIT(IIO_CHAN_INFO_INT_TIME)
97 },
98 {
99 .type = IIO_CURRENT,
100 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
101 .extend_name = "heater",
102 .output = 1,
103 },
104};
105
106static int hdc100x_update_config(struct hdc100x_data *data, int mask, int val)
107{
108 int tmp = (~mask & data->config) | val;
109 int ret;
110
111 ret = i2c_smbus_write_word_swapped(data->client,
112 HDC100X_REG_CONFIG, tmp);
113 if (!ret)
114 data->config = tmp;
115
116 return ret;
117}
118
119static int hdc100x_set_it_time(struct hdc100x_data *data, int chan, int val2)
120{
121 int shift = hdc100x_resolution_shift[chan].shift;
122 int ret = -EINVAL;
123 int i;
124
125 for (i = 0; i < ARRAY_SIZE(hdc100x_int_time[chan]); i++) {
126 if (val2 && val2 == hdc100x_int_time[chan][i]) {
127 ret = hdc100x_update_config(data,
128 hdc100x_resolution_shift[chan].mask << shift,
129 i << shift);
130 if (!ret)
131 data->adc_int_us[chan] = val2;
132 break;
133 }
134 }
135
136 return ret;
137}
138
139static int hdc100x_get_measurement(struct hdc100x_data *data,
140 struct iio_chan_spec const *chan)
141{
142 struct i2c_client *client = data->client;
143 int delay = data->adc_int_us[chan->address];
144 int ret;
145 __be16 val;
146
147
148 ret = i2c_smbus_write_byte(client, chan->address);
149 if (ret < 0) {
150 dev_err(&client->dev, "cannot start measurement");
151 return ret;
152 }
153
154
155 usleep_range(delay, delay + 1000);
156
157
158 ret = i2c_master_recv(data->client, (char *)&val, sizeof(val));
159 if (ret < 0) {
160 dev_err(&client->dev, "cannot read sensor data\n");
161 return ret;
162 }
163 return be16_to_cpu(val);
164}
165
166static int hdc100x_get_heater_status(struct hdc100x_data *data)
167{
168 return !!(data->config & HDC100X_REG_CONFIG_HEATER_EN);
169}
170
171static int hdc100x_read_raw(struct iio_dev *indio_dev,
172 struct iio_chan_spec const *chan, int *val,
173 int *val2, long mask)
174{
175 struct hdc100x_data *data = iio_priv(indio_dev);
176
177 switch (mask) {
178 case IIO_CHAN_INFO_RAW: {
179 int ret;
180
181 mutex_lock(&data->lock);
182 if (chan->type == IIO_CURRENT) {
183 *val = hdc100x_get_heater_status(data);
184 ret = IIO_VAL_INT;
185 } else {
186 ret = hdc100x_get_measurement(data, chan);
187 if (ret >= 0) {
188 *val = ret;
189 ret = IIO_VAL_INT;
190 }
191 }
192 mutex_unlock(&data->lock);
193 return ret;
194 }
195 case IIO_CHAN_INFO_INT_TIME:
196 *val = 0;
197 *val2 = data->adc_int_us[chan->address];
198 return IIO_VAL_INT_PLUS_MICRO;
199 case IIO_CHAN_INFO_SCALE:
200 if (chan->type == IIO_TEMP) {
201 *val = 165000;
202 *val2 = 65536;
203 return IIO_VAL_FRACTIONAL;
204 } else {
205 *val = 100;
206 *val2 = 65536;
207 return IIO_VAL_FRACTIONAL;
208 }
209 break;
210 case IIO_CHAN_INFO_OFFSET:
211 *val = -15887;
212 *val2 = 515151;
213 return IIO_VAL_INT_PLUS_MICRO;
214 default:
215 return -EINVAL;
216 }
217}
218
219static int hdc100x_write_raw(struct iio_dev *indio_dev,
220 struct iio_chan_spec const *chan,
221 int val, int val2, long mask)
222{
223 struct hdc100x_data *data = iio_priv(indio_dev);
224 int ret = -EINVAL;
225
226 switch (mask) {
227 case IIO_CHAN_INFO_INT_TIME:
228 if (val != 0)
229 return -EINVAL;
230
231 mutex_lock(&data->lock);
232 ret = hdc100x_set_it_time(data, chan->address, val2);
233 mutex_unlock(&data->lock);
234 return ret;
235 case IIO_CHAN_INFO_RAW:
236 if (chan->type != IIO_CURRENT || val2 != 0)
237 return -EINVAL;
238
239 mutex_lock(&data->lock);
240 ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_HEATER_EN,
241 val ? HDC100X_REG_CONFIG_HEATER_EN : 0);
242 mutex_unlock(&data->lock);
243 return ret;
244 default:
245 return -EINVAL;
246 }
247}
248
249static const struct iio_info hdc100x_info = {
250 .read_raw = hdc100x_read_raw,
251 .write_raw = hdc100x_write_raw,
252 .attrs = &hdc100x_attribute_group,
253 .driver_module = THIS_MODULE,
254};
255
256static int hdc100x_probe(struct i2c_client *client,
257 const struct i2c_device_id *id)
258{
259 struct iio_dev *indio_dev;
260 struct hdc100x_data *data;
261
262 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA |
263 I2C_FUNC_SMBUS_BYTE | I2C_FUNC_I2C))
264 return -EOPNOTSUPP;
265
266 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
267 if (!indio_dev)
268 return -ENOMEM;
269
270 data = iio_priv(indio_dev);
271 i2c_set_clientdata(client, indio_dev);
272 data->client = client;
273 mutex_init(&data->lock);
274
275 indio_dev->dev.parent = &client->dev;
276 indio_dev->name = dev_name(&client->dev);
277 indio_dev->modes = INDIO_DIRECT_MODE;
278 indio_dev->info = &hdc100x_info;
279
280 indio_dev->channels = hdc100x_channels;
281 indio_dev->num_channels = ARRAY_SIZE(hdc100x_channels);
282
283
284 hdc100x_set_it_time(data, 0, hdc100x_int_time[0][0]);
285 hdc100x_set_it_time(data, 1, hdc100x_int_time[1][0]);
286
287 return devm_iio_device_register(&client->dev, indio_dev);
288}
289
290static const struct i2c_device_id hdc100x_id[] = {
291 { "hdc100x", 0 },
292 { }
293};
294MODULE_DEVICE_TABLE(i2c, hdc100x_id);
295
296static struct i2c_driver hdc100x_driver = {
297 .driver = {
298 .name = "hdc100x",
299 },
300 .probe = hdc100x_probe,
301 .id_table = hdc100x_id,
302};
303module_i2c_driver(hdc100x_driver);
304
305MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>");
306MODULE_DESCRIPTION("TI HDC100x humidity and temperature sensor driver");
307MODULE_LICENSE("GPL");
308
