2 * MS5611 pressure and temperature sensor driver
4 * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
11 * http://www.meas-spec.com/downloads/MS5611-01BA03.pdf
12 * http://www.meas-spec.com/downloads/MS5607-02BA03.pdf
16 #include <linux/module.h>
17 #include <linux/iio/iio.h>
18 #include <linux/delay.h>
19 #include <linux/regulator/consumer.h>
21 #include <linux/iio/sysfs.h>
22 #include <linux/iio/buffer.h>
23 #include <linux/iio/triggered_buffer.h>
24 #include <linux/iio/trigger_consumer.h>
27 #define MS5611_INIT_OSR(_cmd, _conv_usec, _rate) \
28 { .cmd = _cmd, .conv_usec = _conv_usec, .rate = _rate }
30 static const struct ms5611_osr ms5611_avail_pressure_osr[] = {
31 MS5611_INIT_OSR(0x40, 600, 256),
32 MS5611_INIT_OSR(0x42, 1170, 512),
33 MS5611_INIT_OSR(0x44, 2280, 1024),
34 MS5611_INIT_OSR(0x46, 4540, 2048),
35 MS5611_INIT_OSR(0x48, 9040, 4096)
38 static const struct ms5611_osr ms5611_avail_temp_osr[] = {
39 MS5611_INIT_OSR(0x50, 600, 256),
40 MS5611_INIT_OSR(0x52, 1170, 512),
41 MS5611_INIT_OSR(0x54, 2280, 1024),
42 MS5611_INIT_OSR(0x56, 4540, 2048),
43 MS5611_INIT_OSR(0x58, 9040, 4096)
46 static const char ms5611_show_osr[] = "256 512 1024 2048 4096";
48 static IIO_CONST_ATTR(oversampling_ratio_available, ms5611_show_osr);
50 static struct attribute *ms5611_attributes[] = {
51 &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
55 static const struct attribute_group ms5611_attribute_group = {
56 .attrs = ms5611_attributes,
59 static bool ms5611_prom_is_valid(u16 *prom, size_t len)
62 uint16_t crc = 0, crc_orig = prom[7] & 0x000F;
66 for (i = 0; i < len * 2; i++) {
68 crc ^= prom[i >> 1] & 0x00FF;
70 crc ^= prom[i >> 1] >> 8;
72 for (j = 0; j < 8; j++) {
74 crc = (crc << 1) ^ 0x3000;
80 crc = (crc >> 12) & 0x000F;
82 return crc_orig != 0x0000 && crc == crc_orig;
85 static int ms5611_read_prom(struct iio_dev *indio_dev)
88 struct ms5611_state *st = iio_priv(indio_dev);
90 for (i = 0; i < MS5611_PROM_WORDS_NB; i++) {
91 ret = st->read_prom_word(&indio_dev->dev,
92 i, &st->chip_info->prom[i]);
94 dev_err(&indio_dev->dev,
95 "failed to read prom at %d\n", i);
100 if (!ms5611_prom_is_valid(st->chip_info->prom, MS5611_PROM_WORDS_NB)) {
101 dev_err(&indio_dev->dev, "PROM integrity check failed\n");
108 static int ms5611_read_temp_and_pressure(struct iio_dev *indio_dev,
109 s32 *temp, s32 *pressure)
112 struct ms5611_state *st = iio_priv(indio_dev);
114 ret = st->read_adc_temp_and_pressure(&indio_dev->dev, temp, pressure);
116 dev_err(&indio_dev->dev,
117 "failed to read temperature and pressure\n");
121 return st->chip_info->temp_and_pressure_compensate(st->chip_info,
125 static int ms5611_temp_and_pressure_compensate(struct ms5611_chip_info *chip_info,
126 s32 *temp, s32 *pressure)
128 s32 t = *temp, p = *pressure;
131 dt = t - (chip_info->prom[5] << 8);
132 off = ((s64)chip_info->prom[2] << 16) + ((chip_info->prom[4] * dt) >> 7);
133 sens = ((s64)chip_info->prom[1] << 15) + ((chip_info->prom[3] * dt) >> 8);
135 t = 2000 + ((chip_info->prom[6] * dt) >> 23);
139 t2 = (dt * dt) >> 31;
140 off2 = (5 * (t - 2000) * (t - 2000)) >> 1;
144 s64 tmp = (t + 1500) * (t + 1500);
147 sens2 += (11 * tmp) >> 1;
156 *pressure = (((p * sens) >> 21) - off) >> 15;
161 static int ms5607_temp_and_pressure_compensate(struct ms5611_chip_info *chip_info,
162 s32 *temp, s32 *pressure)
164 s32 t = *temp, p = *pressure;
167 dt = t - (chip_info->prom[5] << 8);
168 off = ((s64)chip_info->prom[2] << 17) + ((chip_info->prom[4] * dt) >> 6);
169 sens = ((s64)chip_info->prom[1] << 16) + ((chip_info->prom[3] * dt) >> 7);
171 t = 2000 + ((chip_info->prom[6] * dt) >> 23);
173 s64 off2, sens2, t2, tmp;
175 t2 = (dt * dt) >> 31;
176 tmp = (t - 2000) * (t - 2000);
177 off2 = (61 * tmp) >> 4;
181 tmp = (t + 1500) * (t + 1500);
192 *pressure = (((p * sens) >> 21) - off) >> 15;
197 static int ms5611_reset(struct iio_dev *indio_dev)
200 struct ms5611_state *st = iio_priv(indio_dev);
202 ret = st->reset(&indio_dev->dev);
204 dev_err(&indio_dev->dev, "failed to reset device\n");
208 usleep_range(3000, 4000);
213 static irqreturn_t ms5611_trigger_handler(int irq, void *p)
215 struct iio_poll_func *pf = p;
216 struct iio_dev *indio_dev = pf->indio_dev;
217 struct ms5611_state *st = iio_priv(indio_dev);
218 /* Ensure buffer elements are naturally aligned */
225 mutex_lock(&st->lock);
226 ret = ms5611_read_temp_and_pressure(indio_dev, &scan.channels[1],
228 mutex_unlock(&st->lock);
232 iio_push_to_buffers_with_timestamp(indio_dev, &scan,
233 iio_get_time_ns(indio_dev));
236 iio_trigger_notify_done(indio_dev->trig);
241 static int ms5611_read_raw(struct iio_dev *indio_dev,
242 struct iio_chan_spec const *chan,
243 int *val, int *val2, long mask)
247 struct ms5611_state *st = iio_priv(indio_dev);
250 case IIO_CHAN_INFO_PROCESSED:
251 mutex_lock(&st->lock);
252 ret = ms5611_read_temp_and_pressure(indio_dev,
254 mutex_unlock(&st->lock);
258 switch (chan->type) {
263 *val = pressure / 1000;
264 *val2 = (pressure % 1000) * 1000;
265 return IIO_VAL_INT_PLUS_MICRO;
269 case IIO_CHAN_INFO_SCALE:
270 switch (chan->type) {
277 return IIO_VAL_INT_PLUS_MICRO;
281 case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
282 if (chan->type != IIO_TEMP && chan->type != IIO_PRESSURE)
284 mutex_lock(&st->lock);
285 if (chan->type == IIO_TEMP)
286 *val = (int)st->temp_osr->rate;
288 *val = (int)st->pressure_osr->rate;
289 mutex_unlock(&st->lock);
296 static const struct ms5611_osr *ms5611_find_osr(int rate,
297 const struct ms5611_osr *osr,
302 for (r = 0; r < count; r++)
303 if ((unsigned short)rate == osr[r].rate)
310 static int ms5611_write_raw(struct iio_dev *indio_dev,
311 struct iio_chan_spec const *chan,
312 int val, int val2, long mask)
314 struct ms5611_state *st = iio_priv(indio_dev);
315 const struct ms5611_osr *osr = NULL;
318 if (mask != IIO_CHAN_INFO_OVERSAMPLING_RATIO)
321 if (chan->type == IIO_TEMP)
322 osr = ms5611_find_osr(val, ms5611_avail_temp_osr,
323 ARRAY_SIZE(ms5611_avail_temp_osr));
324 else if (chan->type == IIO_PRESSURE)
325 osr = ms5611_find_osr(val, ms5611_avail_pressure_osr,
326 ARRAY_SIZE(ms5611_avail_pressure_osr));
330 ret = iio_device_claim_direct_mode(indio_dev);
334 mutex_lock(&st->lock);
336 if (chan->type == IIO_TEMP)
339 st->pressure_osr = osr;
341 mutex_unlock(&st->lock);
342 iio_device_release_direct_mode(indio_dev);
347 static const unsigned long ms5611_scan_masks[] = {0x3, 0};
349 static struct ms5611_chip_info chip_info_tbl[] = {
351 .temp_and_pressure_compensate = ms5611_temp_and_pressure_compensate,
354 .temp_and_pressure_compensate = ms5607_temp_and_pressure_compensate,
358 static const struct iio_chan_spec ms5611_channels[] = {
360 .type = IIO_PRESSURE,
361 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
362 BIT(IIO_CHAN_INFO_SCALE) |
363 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
369 .endianness = IIO_CPU,
374 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
375 BIT(IIO_CHAN_INFO_SCALE) |
376 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
382 .endianness = IIO_CPU,
385 IIO_CHAN_SOFT_TIMESTAMP(2),
388 static const struct iio_info ms5611_info = {
389 .read_raw = &ms5611_read_raw,
390 .write_raw = &ms5611_write_raw,
391 .attrs = &ms5611_attribute_group,
394 static int ms5611_init(struct iio_dev *indio_dev)
397 struct ms5611_state *st = iio_priv(indio_dev);
399 /* Enable attached regulator if any. */
400 st->vdd = devm_regulator_get(indio_dev->dev.parent, "vdd");
402 return PTR_ERR(st->vdd);
404 ret = regulator_enable(st->vdd);
406 dev_err(indio_dev->dev.parent,
407 "failed to enable Vdd supply: %d\n", ret);
411 ret = ms5611_reset(indio_dev);
413 goto err_regulator_disable;
415 ret = ms5611_read_prom(indio_dev);
417 goto err_regulator_disable;
421 err_regulator_disable:
422 regulator_disable(st->vdd);
426 static void ms5611_fini(const struct iio_dev *indio_dev)
428 const struct ms5611_state *st = iio_priv(indio_dev);
430 regulator_disable(st->vdd);
433 int ms5611_probe(struct iio_dev *indio_dev, struct device *dev,
434 const char *name, int type)
437 struct ms5611_state *st = iio_priv(indio_dev);
439 mutex_init(&st->lock);
440 st->chip_info = &chip_info_tbl[type];
442 &ms5611_avail_temp_osr[ARRAY_SIZE(ms5611_avail_temp_osr) - 1];
444 &ms5611_avail_pressure_osr[ARRAY_SIZE(ms5611_avail_pressure_osr)
446 indio_dev->dev.parent = dev;
447 indio_dev->name = name;
448 indio_dev->info = &ms5611_info;
449 indio_dev->channels = ms5611_channels;
450 indio_dev->num_channels = ARRAY_SIZE(ms5611_channels);
451 indio_dev->modes = INDIO_DIRECT_MODE;
452 indio_dev->available_scan_masks = ms5611_scan_masks;
454 ret = ms5611_init(indio_dev);
458 ret = iio_triggered_buffer_setup(indio_dev, NULL,
459 ms5611_trigger_handler, NULL);
461 dev_err(dev, "iio triggered buffer setup failed\n");
465 ret = iio_device_register(indio_dev);
467 dev_err(dev, "unable to register iio device\n");
468 goto err_buffer_cleanup;
474 iio_triggered_buffer_cleanup(indio_dev);
476 ms5611_fini(indio_dev);
479 EXPORT_SYMBOL(ms5611_probe);
481 int ms5611_remove(struct iio_dev *indio_dev)
483 iio_device_unregister(indio_dev);
484 iio_triggered_buffer_cleanup(indio_dev);
485 ms5611_fini(indio_dev);
489 EXPORT_SYMBOL(ms5611_remove);
491 MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
492 MODULE_DESCRIPTION("MS5611 core driver");
493 MODULE_LICENSE("GPL v2");