dps310.c

  1// SPDX-License-Identifier: GPL-2.0+
  2// Copyright IBM Corp 2019
  3/*
  4 * The DPS310 is a barometric pressure and temperature sensor.
  5 * Currently only reading a single temperature is supported by
  6 * this driver.
  7 *
  8 * https://www.infineon.com/dgdl/?fileId=5546d462576f34750157750826c42242
  9 *
 10 * Temperature calculation:
 11 *   c0 * 0.5 + c1 * T_raw / kT °C
 12 *
 13 * TODO:
 14 *  - Optionally support the FIFO
 15 */
 16
 17#include <linux/i2c.h>
 18#include <linux/limits.h>
 19#include <linux/math64.h>
 20#include <linux/module.h>
 21#include <linux/regmap.h>
 22
 23#include <linux/iio/iio.h>
 24#include <linux/iio/sysfs.h>
 25
 26#define DPS310_DEV_NAME		"dps310"
 27
 28#define DPS310_PRS_B0		0x00
 29#define DPS310_PRS_B1		0x01
 30#define DPS310_PRS_B2		0x02
 31#define DPS310_TMP_B0		0x03
 32#define DPS310_TMP_B1		0x04
 33#define DPS310_TMP_B2		0x05
 34#define DPS310_PRS_CFG		0x06
 35#define  DPS310_PRS_RATE_BITS	GENMASK(6, 4)
 36#define  DPS310_PRS_PRC_BITS	GENMASK(3, 0)
 37#define DPS310_TMP_CFG		0x07
 38#define  DPS310_TMP_RATE_BITS	GENMASK(6, 4)
 39#define  DPS310_TMP_PRC_BITS	GENMASK(3, 0)
 40#define  DPS310_TMP_EXT		BIT(7)
 41#define DPS310_MEAS_CFG		0x08
 42#define  DPS310_MEAS_CTRL_BITS	GENMASK(2, 0)
 43#define   DPS310_PRS_EN		BIT(0)
 44#define   DPS310_TEMP_EN	BIT(1)
 45#define   DPS310_BACKGROUND	BIT(2)
 46#define  DPS310_PRS_RDY		BIT(4)
 47#define  DPS310_TMP_RDY		BIT(5)
 48#define  DPS310_SENSOR_RDY	BIT(6)
 49#define  DPS310_COEF_RDY	BIT(7)
 50#define DPS310_CFG_REG		0x09
 51#define  DPS310_INT_HL		BIT(7)
 52#define  DPS310_TMP_SHIFT_EN	BIT(3)
 53#define  DPS310_PRS_SHIFT_EN	BIT(4)
 54#define  DPS310_FIFO_EN		BIT(5)
 55#define  DPS310_SPI_EN		BIT(6)
 56#define DPS310_RESET		0x0c
 57#define  DPS310_RESET_MAGIC	0x09
 58#define DPS310_COEF_BASE	0x10
 59
 60/* Make sure sleep time is <= 30ms for usleep_range */
 61#define DPS310_POLL_SLEEP_US(t)		min(30000, (t) / 8)
 62/* Silently handle error in rate value here */
 63#define DPS310_POLL_TIMEOUT_US(rc)	((rc) <= 0 ? 1000000 : 1000000 / (rc))
 64
 65#define DPS310_PRS_BASE		DPS310_PRS_B0
 66#define DPS310_TMP_BASE		DPS310_TMP_B0
 67
 68/*
 69 * These values (defined in the spec) indicate how to scale the raw register
 70 * values for each level of precision available.
 71 */
 72static const int scale_factors[] = {
 73	 524288,
 74	1572864,
 75	3670016,
 76	7864320,
 77	 253952,
 78	 516096,
 79	1040384,
 80	2088960,
 81};
 82
 83struct dps310_data {
 84	struct i2c_client *client;
 85	struct regmap *regmap;
 86	struct mutex lock;	/* Lock for sequential HW access functions */
 87
 88	s32 c0, c1;
 89	s32 c00, c10, c20, c30, c01, c11, c21;
 90	s32 pressure_raw;
 91	s32 temp_raw;
 92	bool timeout_recovery_failed;
 93};
 94
 95static const struct iio_chan_spec dps310_channels[] = {
 96	{
 97		.type = IIO_TEMP,
 98		.info_mask_separate = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) |
 99			BIT(IIO_CHAN_INFO_SAMP_FREQ) |
100			BIT(IIO_CHAN_INFO_PROCESSED),
101	},
102	{
103		.type = IIO_PRESSURE,
104		.info_mask_separate = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) |
105			BIT(IIO_CHAN_INFO_SAMP_FREQ) |
106			BIT(IIO_CHAN_INFO_PROCESSED),
107	},
108};
109
110/* To be called after checking the COEF_RDY bit in MEAS_CFG */
111static int dps310_get_coefs(struct dps310_data *data)
112{
113	int rc;
114	u8 coef[18];
115	u32 c0, c1;
116	u32 c00, c10, c20, c30, c01, c11, c21;
117
118	/* Read all sensor calibration coefficients from the COEF registers. */
119	rc = regmap_bulk_read(data->regmap, DPS310_COEF_BASE, coef,
120			      sizeof(coef));
121	if (rc < 0)
122		return rc;
123
124	/*
125	 * Calculate temperature calibration coefficients c0 and c1. The
126	 * numbers are 12-bit 2's complement numbers.
127	 */
128	c0 = (coef[0] << 4) | (coef[1] >> 4);
129	data->c0 = sign_extend32(c0, 11);
130
131	c1 = ((coef[1] & GENMASK(3, 0)) << 8) | coef[2];
132	data->c1 = sign_extend32(c1, 11);
133
134	/*
135	 * Calculate pressure calibration coefficients. c00 and c10 are 20 bit
136	 * 2's complement numbers, while the rest are 16 bit 2's complement
137	 * numbers.
138	 */
139	c00 = (coef[3] << 12) | (coef[4] << 4) | (coef[5] >> 4);
140	data->c00 = sign_extend32(c00, 19);
141
142	c10 = ((coef[5] & GENMASK(3, 0)) << 16) | (coef[6] << 8) | coef[7];
143	data->c10 = sign_extend32(c10, 19);
144
145	c01 = (coef[8] << 8) | coef[9];
146	data->c01 = sign_extend32(c01, 15);
147
148	c11 = (coef[10] << 8) | coef[11];
149	data->c11 = sign_extend32(c11, 15);
150
151	c20 = (coef[12] << 8) | coef[13];
152	data->c20 = sign_extend32(c20, 15);
153
154	c21 = (coef[14] << 8) | coef[15];
155	data->c21 = sign_extend32(c21, 15);
156
157	c30 = (coef[16] << 8) | coef[17];
158	data->c30 = sign_extend32(c30, 15);
159
160	return 0;
161}
162
163/*
164 * Some versions of the chip will read temperatures in the ~60C range when
165 * it's actually ~20C. This is the manufacturer recommended workaround
166 * to correct the issue. The registers used below are undocumented.
167 */
168static int dps310_temp_workaround(struct dps310_data *data)
169{
170	int rc;
171	int reg;
172
173	rc = regmap_read(data->regmap, 0x32, &reg);
174	if (rc < 0)
175		return rc;
176
177	/*
178	 * If bit 1 is set then the device is okay, and the workaround does not
179	 * need to be applied
180	 */
181	if (reg & BIT(1))
182		return 0;
183
184	rc = regmap_write(data->regmap, 0x0e, 0xA5);
185	if (rc)
186		return rc;
187
188	rc = regmap_write(data->regmap, 0x0f, 0x96);
189	if (rc)
190		return rc;
191
192	rc = regmap_write(data->regmap, 0x62, 0x02);
193	if (rc)
194		return rc;
195
196	rc = regmap_write(data->regmap, 0x0e, 0x00);
197	if (rc)
198		return rc;
199
200	return regmap_write(data->regmap, 0x0f, 0x00);
201}
202
203static int dps310_startup(struct dps310_data *data)
204{
205	int rc;
206	int ready;
207
208	/*
209	 * Set up pressure sensor in single sample, one measurement per second
210	 * mode
211	 */
212	rc = regmap_write(data->regmap, DPS310_PRS_CFG, 0);
213	if (rc)
214		return rc;
215
216	/*
217	 * Set up external (MEMS) temperature sensor in single sample, one
218	 * measurement per second mode
219	 */
220	rc = regmap_write(data->regmap, DPS310_TMP_CFG, DPS310_TMP_EXT);
221	if (rc)
222		return rc;
223
224	/* Temp and pressure shifts are disabled when PRC <= 8 */
225	rc = regmap_write_bits(data->regmap, DPS310_CFG_REG,
226			       DPS310_PRS_SHIFT_EN | DPS310_TMP_SHIFT_EN, 0);
227	if (rc)
228		return rc;
229
230	/* MEAS_CFG doesn't update correctly unless first written with 0 */
231	rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG,
232			       DPS310_MEAS_CTRL_BITS, 0);
233	if (rc)
234		return rc;
235
236	/* Turn on temperature and pressure measurement in the background */
237	rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG,
238			       DPS310_MEAS_CTRL_BITS, DPS310_PRS_EN |
239			       DPS310_TEMP_EN | DPS310_BACKGROUND);
240	if (rc)
241		return rc;
242
243	/*
244	 * Calibration coefficients required for reporting temperature.
245	 * They are available 40ms after the device has started
246	 */
247	rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready,
248				      ready & DPS310_COEF_RDY, 10000, 40000);
249	if (rc)
250		return rc;
251
252	rc = dps310_get_coefs(data);
253	if (rc)
254		return rc;
255
256	return dps310_temp_workaround(data);
257}
258
259static int dps310_get_pres_precision(struct dps310_data *data, int *val)
260{
261	int reg_val, rc;
262
263	rc = regmap_read(data->regmap, DPS310_PRS_CFG, &reg_val);
264	if (rc < 0)
265		return rc;
266
267	*val = BIT(reg_val & GENMASK(2, 0));
268
269	return 0;
270}
271
272static int dps310_get_temp_precision(struct dps310_data *data, int *val)
273{
274	int reg_val, rc;
275
276	rc = regmap_read(data->regmap, DPS310_TMP_CFG, &reg_val);
277	if (rc < 0)
278		return rc;
279
280	/*
281	 * Scale factor is bottom 4 bits of the register, but 1111 is
282	 * reserved so just grab bottom three
283	 */
284	*val = BIT(reg_val & GENMASK(2, 0));
285
286	return 0;
287}
288
289/* Called with lock held */
290static int dps310_set_pres_precision(struct dps310_data *data, int val)
291{
292	int rc;
293	u8 shift_en;
294
295	if (val < 0 || val > 128)
296		return -EINVAL;
297
298	shift_en = val >= 16 ? DPS310_PRS_SHIFT_EN : 0;
299	rc = regmap_write_bits(data->regmap, DPS310_CFG_REG,
300			       DPS310_PRS_SHIFT_EN, shift_en);
301	if (rc)
302		return rc;
303
304	return regmap_update_bits(data->regmap, DPS310_PRS_CFG,
305				  DPS310_PRS_PRC_BITS, ilog2(val));
306}
307
308/* Called with lock held */
309static int dps310_set_temp_precision(struct dps310_data *data, int val)
310{
311	int rc;
312	u8 shift_en;
313
314	if (val < 0 || val > 128)
315		return -EINVAL;
316
317	shift_en = val >= 16 ? DPS310_TMP_SHIFT_EN : 0;
318	rc = regmap_write_bits(data->regmap, DPS310_CFG_REG,
319			       DPS310_TMP_SHIFT_EN, shift_en);
320	if (rc)
321		return rc;
322
323	return regmap_update_bits(data->regmap, DPS310_TMP_CFG,
324				  DPS310_TMP_PRC_BITS, ilog2(val));
325}
326
327/* Called with lock held */
328static int dps310_set_pres_samp_freq(struct dps310_data *data, int freq)
329{
330	u8 val;
331
332	if (freq < 0 || freq > 128)
333		return -EINVAL;
334
335	val = ilog2(freq) << 4;
336
337	return regmap_update_bits(data->regmap, DPS310_PRS_CFG,
338				  DPS310_PRS_RATE_BITS, val);
339}
340
341/* Called with lock held */
342static int dps310_set_temp_samp_freq(struct dps310_data *data, int freq)
343{
344	u8 val;
345
346	if (freq < 0 || freq > 128)
347		return -EINVAL;
348
349	val = ilog2(freq) << 4;
350
351	return regmap_update_bits(data->regmap, DPS310_TMP_CFG,
352				  DPS310_TMP_RATE_BITS, val);
353}
354
355static int dps310_get_pres_samp_freq(struct dps310_data *data, int *val)
356{
357	int reg_val, rc;
358
359	rc = regmap_read(data->regmap, DPS310_PRS_CFG, &reg_val);
360	if (rc < 0)
361		return rc;
362
363	*val = BIT((reg_val & DPS310_PRS_RATE_BITS) >> 4);
364
365	return 0;
366}
367
368static int dps310_get_temp_samp_freq(struct dps310_data *data, int *val)
369{
370	int reg_val, rc;
371
372	rc = regmap_read(data->regmap, DPS310_TMP_CFG, &reg_val);
373	if (rc < 0)
374		return rc;
375
376	*val = BIT((reg_val & DPS310_TMP_RATE_BITS) >> 4);
377
378	return 0;
379}
380
381static int dps310_get_pres_k(struct dps310_data *data, int *val)
382{
383	int reg_val, rc;
384
385	rc = regmap_read(data->regmap, DPS310_PRS_CFG, &reg_val);
386	if (rc < 0)
387		return rc;
388
389	*val = scale_factors[reg_val & GENMASK(2, 0)];
390
391	return 0;
392}
393
394static int dps310_get_temp_k(struct dps310_data *data, int *val)
395{
396	int reg_val, rc;
397
398	rc = regmap_read(data->regmap, DPS310_TMP_CFG, &reg_val);
399	if (rc < 0)
400		return rc;
401
402	*val = scale_factors[reg_val & GENMASK(2, 0)];
403
404	return 0;
405}
406
407static int dps310_reset_wait(struct dps310_data *data)
408{
409	int rc;
410
411	rc = regmap_write(data->regmap, DPS310_RESET, DPS310_RESET_MAGIC);
412	if (rc)
413		return rc;
414
415	/* Wait for device chip access: 15ms in specification */
416	usleep_range(15000, 55000);
417	return 0;
418}
419
420static int dps310_reset_reinit(struct dps310_data *data)
421{
422	int rc;
423
424	rc = dps310_reset_wait(data);
425	if (rc)
426		return rc;
427
428	return dps310_startup(data);
429}
430
431static int dps310_ready_status(struct dps310_data *data, int ready_bit, int timeout)
432{
433	int sleep = DPS310_POLL_SLEEP_US(timeout);
434	int ready;
435
436	return regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready, ready & ready_bit,
437					sleep, timeout);
438}
439
440static int dps310_ready(struct dps310_data *data, int ready_bit, int timeout)
441{
442	int rc;
443
444	rc = dps310_ready_status(data, ready_bit, timeout);
445	if (rc) {
446		if (rc == -ETIMEDOUT && !data->timeout_recovery_failed) {
447			/* Reset and reinitialize the chip. */
448			if (dps310_reset_reinit(data)) {
449				data->timeout_recovery_failed = true;
450			} else {
451				/* Try again to get sensor ready status. */
452				if (dps310_ready_status(data, ready_bit, timeout))
453					data->timeout_recovery_failed = true;
454				else
455					return 0;
456			}
457		}
458
459		return rc;
460	}
461
462	data->timeout_recovery_failed = false;
463	return 0;
464}
465
466static int dps310_read_pres_raw(struct dps310_data *data)
467{
468	int rc;
469	int rate;
470	int timeout;
471	s32 raw;
472	u8 val[3];
473
474	if (mutex_lock_interruptible(&data->lock))
475		return -EINTR;
476
477	rc = dps310_get_pres_samp_freq(data, &rate);
478	if (rc)
479		goto done;
480
481	timeout = DPS310_POLL_TIMEOUT_US(rate);
482
483	/* Poll for sensor readiness; base the timeout upon the sample rate. */
484	rc = dps310_ready(data, DPS310_PRS_RDY, timeout);
485	if (rc)
486		goto done;
487
488	rc = regmap_bulk_read(data->regmap, DPS310_PRS_BASE, val, sizeof(val));
489	if (rc < 0)
490		goto done;
491
492	raw = (val[0] << 16) | (val[1] << 8) | val[2];
493	data->pressure_raw = sign_extend32(raw, 23);
494
495done:
496	mutex_unlock(&data->lock);
497	return rc;
498}
499
500/* Called with lock held */
501static int dps310_read_temp_ready(struct dps310_data *data)
502{
503	int rc;
504	u8 val[3];
505	s32 raw;
506
507	rc = regmap_bulk_read(data->regmap, DPS310_TMP_BASE, val, sizeof(val));
508	if (rc < 0)
509		return rc;
510
511	raw = (val[0] << 16) | (val[1] << 8) | val[2];
512	data->temp_raw = sign_extend32(raw, 23);
513
514	return 0;
515}
516
517static int dps310_read_temp_raw(struct dps310_data *data)
518{
519	int rc;
520	int rate;
521	int timeout;
522
523	if (mutex_lock_interruptible(&data->lock))
524		return -EINTR;
525
526	rc = dps310_get_temp_samp_freq(data, &rate);
527	if (rc)
528		goto done;
529
530	timeout = DPS310_POLL_TIMEOUT_US(rate);
531
532	/* Poll for sensor readiness; base the timeout upon the sample rate. */
533	rc = dps310_ready(data, DPS310_TMP_RDY, timeout);
534	if (rc)
535		goto done;
536
537	rc = dps310_read_temp_ready(data);
538
539done:
540	mutex_unlock(&data->lock);
541	return rc;
542}
543
544static bool dps310_is_writeable_reg(struct device *dev, unsigned int reg)
545{
546	switch (reg) {
547	case DPS310_PRS_CFG:
548	case DPS310_TMP_CFG:
549	case DPS310_MEAS_CFG:
550	case DPS310_CFG_REG:
551	case DPS310_RESET:
552	/* No documentation available on the registers below */
553	case 0x0e:
554	case 0x0f:
555	case 0x62:
556		return true;
557	default:
558		return false;
559	}
560}
561
562static bool dps310_is_volatile_reg(struct device *dev, unsigned int reg)
563{
564	switch (reg) {
565	case DPS310_PRS_B0:
566	case DPS310_PRS_B1:
567	case DPS310_PRS_B2:
568	case DPS310_TMP_B0:
569	case DPS310_TMP_B1:
570	case DPS310_TMP_B2:
571	case DPS310_MEAS_CFG:
572	case 0x32:	/* No documentation available on this register */
573		return true;
574	default:
575		return false;
576	}
577}
578
579static int dps310_write_raw(struct iio_dev *iio,
580			    struct iio_chan_spec const *chan, int val,
581			    int val2, long mask)
582{
583	int rc;
584	struct dps310_data *data = iio_priv(iio);
585
586	if (mutex_lock_interruptible(&data->lock))
587		return -EINTR;
588
589	switch (mask) {
590	case IIO_CHAN_INFO_SAMP_FREQ:
591		switch (chan->type) {
592		case IIO_PRESSURE:
593			rc = dps310_set_pres_samp_freq(data, val);
594			break;
595
596		case IIO_TEMP:
597			rc = dps310_set_temp_samp_freq(data, val);
598			break;
599
600		default:
601			rc = -EINVAL;
602			break;
603		}
604		break;
605
606	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
607		switch (chan->type) {
608		case IIO_PRESSURE:
609			rc = dps310_set_pres_precision(data, val);
610			break;
611
612		case IIO_TEMP:
613			rc = dps310_set_temp_precision(data, val);
614			break;
615
616		default:
617			rc = -EINVAL;
618			break;
619		}
620		break;
621
622	default:
623		rc = -EINVAL;
624		break;
625	}
626
627	mutex_unlock(&data->lock);
628	return rc;
629}
630
631static int dps310_calculate_pressure(struct dps310_data *data, int *val)
632{
633	int i;
634	int rc;
635	int t_ready;
636	int kpi;
637	int kti;
638	s64 rem = 0ULL;
639	s64 pressure = 0ULL;
640	s64 p;
641	s64 t;
642	s64 denoms[7];
643	s64 nums[7];
644	s64 rems[7];
645	s64 kp;
646	s64 kt;
647
648	rc = dps310_get_pres_k(data, &kpi);
649	if (rc)
650		return rc;
651
652	rc = dps310_get_temp_k(data, &kti);
653	if (rc)
654		return rc;
655
656	kp = (s64)kpi;
657	kt = (s64)kti;
658
659	/* Refresh temp if it's ready, otherwise just use the latest value */
660	if (mutex_trylock(&data->lock)) {
661		rc = regmap_read(data->regmap, DPS310_MEAS_CFG, &t_ready);
662		if (rc >= 0 && t_ready & DPS310_TMP_RDY)
663			dps310_read_temp_ready(data);
664
665		mutex_unlock(&data->lock);
666	}
667
668	p = (s64)data->pressure_raw;
669	t = (s64)data->temp_raw;
670
671	/* Section 4.9.1 of the DPS310 spec; algebra'd to avoid underflow */
672	nums[0] = (s64)data->c00;
673	denoms[0] = 1LL;
674	nums[1] = p * (s64)data->c10;
675	denoms[1] = kp;
676	nums[2] = p * p * (s64)data->c20;
677	denoms[2] = kp * kp;
678	nums[3] = p * p * p * (s64)data->c30;
679	denoms[3] = kp * kp * kp;
680	nums[4] = t * (s64)data->c01;
681	denoms[4] = kt;
682	nums[5] = t * p * (s64)data->c11;
683	denoms[5] = kp * kt;
684	nums[6] = t * p * p * (s64)data->c21;
685	denoms[6] = kp * kp * kt;
686
687	/* Kernel lacks a div64_s64_rem function; denoms are all positive */
688	for (i = 0; i < 7; ++i) {
689		u64 irem;
690
691		if (nums[i] < 0LL) {
692			pressure -= div64_u64_rem(-nums[i], denoms[i], &irem);
693			rems[i] = -irem;
694		} else {
695			pressure += div64_u64_rem(nums[i], denoms[i], &irem);
696			rems[i] = (s64)irem;
697		}
698	}
699
700	/* Increase precision and calculate the remainder sum */
701	for (i = 0; i < 7; ++i)
702		rem += div64_s64((s64)rems[i] * 1000000000LL, denoms[i]);
703
704	pressure += div_s64(rem, 1000000000LL);
705	if (pressure < 0LL)
706		return -ERANGE;
707
708	*val = (int)min_t(s64, pressure, INT_MAX);
709
710	return 0;
711}
712
713static int dps310_read_pressure(struct dps310_data *data, int *val, int *val2,
714				long mask)
715{
716	int rc;
717
718	switch (mask) {
719	case IIO_CHAN_INFO_SAMP_FREQ:
720		rc = dps310_get_pres_samp_freq(data, val);
721		if (rc)
722			return rc;
723
724		return IIO_VAL_INT;
725
726	case IIO_CHAN_INFO_PROCESSED:
727		rc = dps310_read_pres_raw(data);
728		if (rc)
729			return rc;
730
731		rc = dps310_calculate_pressure(data, val);
732		if (rc)
733			return rc;
734
735		*val2 = 1000; /* Convert Pa to KPa per IIO ABI */
736		return IIO_VAL_FRACTIONAL;
737
738	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
739		rc = dps310_get_pres_precision(data, val);
740		if (rc)
741			return rc;
742		return IIO_VAL_INT;
743
744	default:
745		return -EINVAL;
746	}
747}
748
749static int dps310_calculate_temp(struct dps310_data *data, int *val)
750{
751	s64 c0;
752	s64 t;
753	int kt, rc;
754
755	rc = dps310_get_temp_k(data, &kt);
756	if (rc)
757		return rc;
758
759	/* Obtain inverse-scaled offset */
760	c0 = div_s64((s64)kt * (s64)data->c0, 2);
761
762	/* Add the offset to the unscaled temperature */
763	t = c0 + ((s64)data->temp_raw * (s64)data->c1);
764
765	/* Convert to milliCelsius and scale the temperature */
766	*val = (int)div_s64(t * 1000LL, kt);
767
768	return 0;
769}
770
771static int dps310_read_temp(struct dps310_data *data, int *val, int *val2,
772			    long mask)
773{
774	int rc;
775
776	switch (mask) {
777	case IIO_CHAN_INFO_SAMP_FREQ:
778		rc = dps310_get_temp_samp_freq(data, val);
779		if (rc)
780			return rc;
781
782		return IIO_VAL_INT;
783
784	case IIO_CHAN_INFO_PROCESSED:
785		rc = dps310_read_temp_raw(data);
786		if (rc)
787			return rc;
788
789		rc = dps310_calculate_temp(data, val);
790		if (rc)
791			return rc;
792
793		return IIO_VAL_INT;
794
795	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
796		rc = dps310_get_temp_precision(data, val);
797		if (rc)
798			return rc;
799
800		return IIO_VAL_INT;
801
802	default:
803		return -EINVAL;
804	}
805}
806
807static int dps310_read_raw(struct iio_dev *iio,
808			   struct iio_chan_spec const *chan,
809			   int *val, int *val2, long mask)
810{
811	struct dps310_data *data = iio_priv(iio);
812
813	switch (chan->type) {
814	case IIO_PRESSURE:
815		return dps310_read_pressure(data, val, val2, mask);
816
817	case IIO_TEMP:
818		return dps310_read_temp(data, val, val2, mask);
819
820	default:
821		return -EINVAL;
822	}
823}
824
825static void dps310_reset(void *action_data)
826{
827	struct dps310_data *data = action_data;
828
829	dps310_reset_wait(data);
830}
831
832static const struct regmap_config dps310_regmap_config = {
833	.reg_bits = 8,
834	.val_bits = 8,
835	.writeable_reg = dps310_is_writeable_reg,
836	.volatile_reg = dps310_is_volatile_reg,
837	.cache_type = REGCACHE_RBTREE,
838	.max_register = 0x62, /* No documentation available on this register */
839};
840
841static const struct iio_info dps310_info = {
842	.read_raw = dps310_read_raw,
843	.write_raw = dps310_write_raw,
844};
845
846static int dps310_probe(struct i2c_client *client)
847{
848	const struct i2c_device_id *id = i2c_client_get_device_id(client);
849	struct dps310_data *data;
850	struct iio_dev *iio;
851	int rc;
852
853	iio = devm_iio_device_alloc(&client->dev,  sizeof(*data));
854	if (!iio)
855		return -ENOMEM;
856
857	data = iio_priv(iio);
858	data->client = client;
859	mutex_init(&data->lock);
860
861	iio->name = id->name;
862	iio->channels = dps310_channels;
863	iio->num_channels = ARRAY_SIZE(dps310_channels);
864	iio->info = &dps310_info;
865	iio->modes = INDIO_DIRECT_MODE;
866
867	data->regmap = devm_regmap_init_i2c(client, &dps310_regmap_config);
868	if (IS_ERR(data->regmap))
869		return PTR_ERR(data->regmap);
870
871	/* Register to run the device reset when the device is removed */
872	rc = devm_add_action_or_reset(&client->dev, dps310_reset, data);
873	if (rc)
874		return rc;
875
876	rc = dps310_startup(data);
877	if (rc)
878		return rc;
879
880	rc = devm_iio_device_register(&client->dev, iio);
881	if (rc)
882		return rc;
883
884	i2c_set_clientdata(client, iio);
885
886	return 0;
887}
888
889static const struct i2c_device_id dps310_id[] = {
890	{ DPS310_DEV_NAME },
891	{ }
892};
893MODULE_DEVICE_TABLE(i2c, dps310_id);
894
895static const struct acpi_device_id dps310_acpi_match[] = {
896	{ "IFX3100" },
897	{ }
898};
899MODULE_DEVICE_TABLE(acpi, dps310_acpi_match);
900
901static struct i2c_driver dps310_driver = {
902	.driver = {
903		.name = DPS310_DEV_NAME,
904		.acpi_match_table = dps310_acpi_match,
905	},
906	.probe = dps310_probe,
907	.id_table = dps310_id,
908};
909module_i2c_driver(dps310_driver);
910
911MODULE_AUTHOR("Joel Stanley <joel@jms.id.au>");
912MODULE_DESCRIPTION("Infineon DPS310 pressure and temperature sensor");
913MODULE_LICENSE("GPL v2");