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16#include <linux/module.h>
17#include <linux/iio/iio.h>
18#include <linux/delay.h>
19#include <linux/regulator/consumer.h>
20
21#include <linux/iio/buffer.h>
22#include <linux/iio/triggered_buffer.h>
23#include <linux/iio/trigger_consumer.h>
24#include "ms5611.h"
25
26static bool ms5611_prom_is_valid(u16 *prom, size_t len)
27{
28 int i, j;
29 uint16_t crc = 0, crc_orig = prom[7] & 0x000F;
30
31 prom[7] &= 0xFF00;
32
33 for (i = 0; i < len * 2; i++) {
34 if (i % 2 == 1)
35 crc ^= prom[i >> 1] & 0x00FF;
36 else
37 crc ^= prom[i >> 1] >> 8;
38
39 for (j = 0; j < 8; j++) {
40 if (crc & 0x8000)
41 crc = (crc << 1) ^ 0x3000;
42 else
43 crc <<= 1;
44 }
45 }
46
47 crc = (crc >> 12) & 0x000F;
48
49 return crc_orig != 0x0000 && crc == crc_orig;
50}
51
52static int ms5611_read_prom(struct iio_dev *indio_dev)
53{
54 int ret, i;
55 struct ms5611_state *st = iio_priv(indio_dev);
56
57 for (i = 0; i < MS5611_PROM_WORDS_NB; i++) {
58 ret = st->read_prom_word(&indio_dev->dev,
59 i, &st->chip_info->prom[i]);
60 if (ret < 0) {
61 dev_err(&indio_dev->dev,
62 "failed to read prom at %d\n", i);
63 return ret;
64 }
65 }
66
67 if (!ms5611_prom_is_valid(st->chip_info->prom, MS5611_PROM_WORDS_NB)) {
68 dev_err(&indio_dev->dev, "PROM integrity check failed\n");
69 return -ENODEV;
70 }
71
72 return 0;
73}
74
75static int ms5611_read_temp_and_pressure(struct iio_dev *indio_dev,
76 s32 *temp, s32 *pressure)
77{
78 int ret;
79 struct ms5611_state *st = iio_priv(indio_dev);
80
81 ret = st->read_adc_temp_and_pressure(&indio_dev->dev, temp, pressure);
82 if (ret < 0) {
83 dev_err(&indio_dev->dev,
84 "failed to read temperature and pressure\n");
85 return ret;
86 }
87
88 return st->chip_info->temp_and_pressure_compensate(st->chip_info,
89 temp, pressure);
90}
91
92static int ms5611_temp_and_pressure_compensate(struct ms5611_chip_info *chip_info,
93 s32 *temp, s32 *pressure)
94{
95 s32 t = *temp, p = *pressure;
96 s64 off, sens, dt;
97
98 dt = t - (chip_info->prom[5] << 8);
99 off = ((s64)chip_info->prom[2] << 16) + ((chip_info->prom[4] * dt) >> 7);
100 sens = ((s64)chip_info->prom[1] << 15) + ((chip_info->prom[3] * dt) >> 8);
101
102 t = 2000 + ((chip_info->prom[6] * dt) >> 23);
103 if (t < 2000) {
104 s64 off2, sens2, t2;
105
106 t2 = (dt * dt) >> 31;
107 off2 = (5 * (t - 2000) * (t - 2000)) >> 1;
108 sens2 = off2 >> 1;
109
110 if (t < -1500) {
111 s64 tmp = (t + 1500) * (t + 1500);
112
113 off2 += 7 * tmp;
114 sens2 += (11 * tmp) >> 1;
115 }
116
117 t -= t2;
118 off -= off2;
119 sens -= sens2;
120 }
121
122 *temp = t;
123 *pressure = (((p * sens) >> 21) - off) >> 15;
124
125 return 0;
126}
127
128static int ms5607_temp_and_pressure_compensate(struct ms5611_chip_info *chip_info,
129 s32 *temp, s32 *pressure)
130{
131 s32 t = *temp, p = *pressure;
132 s64 off, sens, dt;
133
134 dt = t - (chip_info->prom[5] << 8);
135 off = ((s64)chip_info->prom[2] << 17) + ((chip_info->prom[4] * dt) >> 6);
136 sens = ((s64)chip_info->prom[1] << 16) + ((chip_info->prom[3] * dt) >> 7);
137
138 t = 2000 + ((chip_info->prom[6] * dt) >> 23);
139 if (t < 2000) {
140 s64 off2, sens2, t2, tmp;
141
142 t2 = (dt * dt) >> 31;
143 tmp = (t - 2000) * (t - 2000);
144 off2 = (61 * tmp) >> 4;
145 sens2 = tmp << 1;
146
147 if (t < -1500) {
148 tmp = (t + 1500) * (t + 1500);
149 off2 += 15 * tmp;
150 sens2 += 8 * tmp;
151 }
152
153 t -= t2;
154 off -= off2;
155 sens -= sens2;
156 }
157
158 *temp = t;
159 *pressure = (((p * sens) >> 21) - off) >> 15;
160
161 return 0;
162}
163
164static int ms5611_reset(struct iio_dev *indio_dev)
165{
166 int ret;
167 struct ms5611_state *st = iio_priv(indio_dev);
168
169 ret = st->reset(&indio_dev->dev);
170 if (ret < 0) {
171 dev_err(&indio_dev->dev, "failed to reset device\n");
172 return ret;
173 }
174
175 usleep_range(3000, 4000);
176
177 return 0;
178}
179
180static irqreturn_t ms5611_trigger_handler(int irq, void *p)
181{
182 struct iio_poll_func *pf = p;
183 struct iio_dev *indio_dev = pf->indio_dev;
184 struct ms5611_state *st = iio_priv(indio_dev);
185 s32 buf[4];
186 int ret;
187
188 mutex_lock(&st->lock);
189 ret = ms5611_read_temp_and_pressure(indio_dev, &buf[1], &buf[0]);
190 mutex_unlock(&st->lock);
191 if (ret < 0)
192 goto err;
193
194 iio_push_to_buffers_with_timestamp(indio_dev, buf, iio_get_time_ns());
195
196err:
197 iio_trigger_notify_done(indio_dev->trig);
198
199 return IRQ_HANDLED;
200}
201
202static int ms5611_read_raw(struct iio_dev *indio_dev,
203 struct iio_chan_spec const *chan,
204 int *val, int *val2, long mask)
205{
206 int ret;
207 s32 temp, pressure;
208 struct ms5611_state *st = iio_priv(indio_dev);
209
210 switch (mask) {
211 case IIO_CHAN_INFO_PROCESSED:
212 mutex_lock(&st->lock);
213 ret = ms5611_read_temp_and_pressure(indio_dev,
214 &temp, &pressure);
215 mutex_unlock(&st->lock);
216 if (ret < 0)
217 return ret;
218
219 switch (chan->type) {
220 case IIO_TEMP:
221 *val = temp * 10;
222 return IIO_VAL_INT;
223 case IIO_PRESSURE:
224 *val = pressure / 1000;
225 *val2 = (pressure % 1000) * 1000;
226 return IIO_VAL_INT_PLUS_MICRO;
227 default:
228 return -EINVAL;
229 }
230 case IIO_CHAN_INFO_SCALE:
231 switch (chan->type) {
232 case IIO_TEMP:
233 *val = 10;
234 return IIO_VAL_INT;
235 case IIO_PRESSURE:
236 *val = 0;
237 *val2 = 1000;
238 return IIO_VAL_INT_PLUS_MICRO;
239 default:
240 return -EINVAL;
241 }
242 }
243
244 return -EINVAL;
245}
246
247static const unsigned long ms5611_scan_masks[] = {0x3, 0};
248
249static struct ms5611_chip_info chip_info_tbl[] = {
250 [MS5611] = {
251 .temp_and_pressure_compensate = ms5611_temp_and_pressure_compensate,
252 },
253 [MS5607] = {
254 .temp_and_pressure_compensate = ms5607_temp_and_pressure_compensate,
255 }
256};
257
258static const struct iio_chan_spec ms5611_channels[] = {
259 {
260 .type = IIO_PRESSURE,
261 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
262 BIT(IIO_CHAN_INFO_SCALE),
263 .scan_index = 0,
264 .scan_type = {
265 .sign = 's',
266 .realbits = 32,
267 .storagebits = 32,
268 .endianness = IIO_CPU,
269 },
270 },
271 {
272 .type = IIO_TEMP,
273 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
274 BIT(IIO_CHAN_INFO_SCALE),
275 .scan_index = 1,
276 .scan_type = {
277 .sign = 's',
278 .realbits = 32,
279 .storagebits = 32,
280 .endianness = IIO_CPU,
281 },
282 },
283 IIO_CHAN_SOFT_TIMESTAMP(2),
284};
285
286static const struct iio_info ms5611_info = {
287 .read_raw = &ms5611_read_raw,
288 .driver_module = THIS_MODULE,
289};
290
291static int ms5611_init(struct iio_dev *indio_dev)
292{
293 int ret;
294 struct regulator *vdd = devm_regulator_get(indio_dev->dev.parent,
295 "vdd");
296
297
298 if (!IS_ERR(vdd)) {
299 ret = regulator_enable(vdd);
300 if (ret) {
301 dev_err(indio_dev->dev.parent,
302 "failed to enable Vdd supply: %d\n", ret);
303 return ret;
304 }
305 }
306
307 ret = ms5611_reset(indio_dev);
308 if (ret < 0)
309 return ret;
310
311 return ms5611_read_prom(indio_dev);
312}
313
314int ms5611_probe(struct iio_dev *indio_dev, struct device *dev,
315 const char *name, int type)
316{
317 int ret;
318 struct ms5611_state *st = iio_priv(indio_dev);
319
320 mutex_init(&st->lock);
321 st->chip_info = &chip_info_tbl[type];
322 indio_dev->dev.parent = dev;
323 indio_dev->name = name;
324 indio_dev->info = &ms5611_info;
325 indio_dev->channels = ms5611_channels;
326 indio_dev->num_channels = ARRAY_SIZE(ms5611_channels);
327 indio_dev->modes = INDIO_DIRECT_MODE;
328 indio_dev->available_scan_masks = ms5611_scan_masks;
329
330 ret = ms5611_init(indio_dev);
331 if (ret < 0)
332 return ret;
333
334 ret = iio_triggered_buffer_setup(indio_dev, NULL,
335 ms5611_trigger_handler, NULL);
336 if (ret < 0) {
337 dev_err(dev, "iio triggered buffer setup failed\n");
338 return ret;
339 }
340
341 ret = iio_device_register(indio_dev);
342 if (ret < 0) {
343 dev_err(dev, "unable to register iio device\n");
344 goto err_buffer_cleanup;
345 }
346
347 return 0;
348
349err_buffer_cleanup:
350 iio_triggered_buffer_cleanup(indio_dev);
351
352 return ret;
353}
354EXPORT_SYMBOL(ms5611_probe);
355
356int ms5611_remove(struct iio_dev *indio_dev)
357{
358 iio_device_unregister(indio_dev);
359 iio_triggered_buffer_cleanup(indio_dev);
360
361 return 0;
362}
363EXPORT_SYMBOL(ms5611_remove);
364
365MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
366MODULE_DESCRIPTION("MS5611 core driver");
367MODULE_LICENSE("GPL v2");
368
