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)
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)
260{
261	int rc;
262	int val;
263
264	rc = regmap_read(data->regmap, DPS310_PRS_CFG, &val);
265	if (rc < 0)
266		return rc;
267
268	return BIT(val & GENMASK(2, 0));
269}
270
271static int dps310_get_temp_precision(struct dps310_data *data)
272{
273	int rc;
274	int val;
275
276	rc = regmap_read(data->regmap, DPS310_TMP_CFG, &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	return BIT(val & GENMASK(2, 0));
285}
286
287/* Called with lock held */
288static int dps310_set_pres_precision(struct dps310_data *data, int val)
289{
290	int rc;
291	u8 shift_en;
292
293	if (val < 0 || val > 128)
294		return -EINVAL;
295
296	shift_en = val >= 16 ? DPS310_PRS_SHIFT_EN : 0;
297	rc = regmap_write_bits(data->regmap, DPS310_CFG_REG,
298			       DPS310_PRS_SHIFT_EN, shift_en);
299	if (rc)
300		return rc;
301
302	return regmap_update_bits(data->regmap, DPS310_PRS_CFG,
303				  DPS310_PRS_PRC_BITS, ilog2(val));
304}
305
306/* Called with lock held */
307static int dps310_set_temp_precision(struct dps310_data *data, int val)
308{
309	int rc;
310	u8 shift_en;
311
312	if (val < 0 || val > 128)
313		return -EINVAL;
314
315	shift_en = val >= 16 ? DPS310_TMP_SHIFT_EN : 0;
316	rc = regmap_write_bits(data->regmap, DPS310_CFG_REG,
317			       DPS310_TMP_SHIFT_EN, shift_en);
318	if (rc)
319		return rc;
320
321	return regmap_update_bits(data->regmap, DPS310_TMP_CFG,
322				  DPS310_TMP_PRC_BITS, ilog2(val));
323}
324
325/* Called with lock held */
326static int dps310_set_pres_samp_freq(struct dps310_data *data, int freq)
327{
328	u8 val;
329
330	if (freq < 0 || freq > 128)
331		return -EINVAL;
332
333	val = ilog2(freq) << 4;
334
335	return regmap_update_bits(data->regmap, DPS310_PRS_CFG,
336				  DPS310_PRS_RATE_BITS, val);
337}
338
339/* Called with lock held */
340static int dps310_set_temp_samp_freq(struct dps310_data *data, int freq)
341{
342	u8 val;
343
344	if (freq < 0 || freq > 128)
345		return -EINVAL;
346
347	val = ilog2(freq) << 4;
348
349	return regmap_update_bits(data->regmap, DPS310_TMP_CFG,
350				  DPS310_TMP_RATE_BITS, val);
351}
352
353static int dps310_get_pres_samp_freq(struct dps310_data *data)
354{
355	int rc;
356	int val;
357
358	rc = regmap_read(data->regmap, DPS310_PRS_CFG, &val);
359	if (rc < 0)
360		return rc;
361
362	return BIT((val & DPS310_PRS_RATE_BITS) >> 4);
363}
364
365static int dps310_get_temp_samp_freq(struct dps310_data *data)
366{
367	int rc;
368	int val;
369
370	rc = regmap_read(data->regmap, DPS310_TMP_CFG, &val);
371	if (rc < 0)
372		return rc;
373
374	return BIT((val & DPS310_TMP_RATE_BITS) >> 4);
375}
376
377static int dps310_get_pres_k(struct dps310_data *data)
378{
379	int rc = dps310_get_pres_precision(data);
380
381	if (rc < 0)
382		return rc;
383
384	return scale_factors[ilog2(rc)];
385}
386
387static int dps310_get_temp_k(struct dps310_data *data)
388{
389	int rc = dps310_get_temp_precision(data);
390
391	if (rc < 0)
392		return rc;
393
394	return scale_factors[ilog2(rc)];
395}
396
397static int dps310_reset_wait(struct dps310_data *data)
398{
399	int rc;
400
401	rc = regmap_write(data->regmap, DPS310_RESET, DPS310_RESET_MAGIC);
402	if (rc)
403		return rc;
404
405	/* Wait for device chip access: 15ms in specification */
406	usleep_range(15000, 55000);
407	return 0;
408}
409
410static int dps310_reset_reinit(struct dps310_data *data)
411{
412	int rc;
413
414	rc = dps310_reset_wait(data);
415	if (rc)
416		return rc;
417
418	return dps310_startup(data);
419}
420
421static int dps310_ready_status(struct dps310_data *data, int ready_bit, int timeout)
422{
423	int sleep = DPS310_POLL_SLEEP_US(timeout);
424	int ready;
425
426	return regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready, ready & ready_bit,
427					sleep, timeout);
428}
429
430static int dps310_ready(struct dps310_data *data, int ready_bit, int timeout)
431{
432	int rc;
433
434	rc = dps310_ready_status(data, ready_bit, timeout);
435	if (rc) {
436		if (rc == -ETIMEDOUT && !data->timeout_recovery_failed) {
437			/* Reset and reinitialize the chip. */
438			if (dps310_reset_reinit(data)) {
439				data->timeout_recovery_failed = true;
440			} else {
441				/* Try again to get sensor ready status. */
442				if (dps310_ready_status(data, ready_bit, timeout))
443					data->timeout_recovery_failed = true;
444				else
445					return 0;
446			}
447		}
448
449		return rc;
450	}
451
452	data->timeout_recovery_failed = false;
453	return 0;
454}
455
456static int dps310_read_pres_raw(struct dps310_data *data)
457{
458	int rc;
459	int rate;
460	int timeout;
461	s32 raw;
462	u8 val[3];
463
464	if (mutex_lock_interruptible(&data->lock))
465		return -EINTR;
466
467	rate = dps310_get_pres_samp_freq(data);
468	timeout = DPS310_POLL_TIMEOUT_US(rate);
469
470	/* Poll for sensor readiness; base the timeout upon the sample rate. */
471	rc = dps310_ready(data, DPS310_PRS_RDY, timeout);
472	if (rc)
473		goto done;
474
475	rc = regmap_bulk_read(data->regmap, DPS310_PRS_BASE, val, sizeof(val));
476	if (rc < 0)
477		goto done;
478
479	raw = (val[0] << 16) | (val[1] << 8) | val[2];
480	data->pressure_raw = sign_extend32(raw, 23);
481
482done:
483	mutex_unlock(&data->lock);
484	return rc;
485}
486
487/* Called with lock held */
488static int dps310_read_temp_ready(struct dps310_data *data)
489{
490	int rc;
491	u8 val[3];
492	s32 raw;
493
494	rc = regmap_bulk_read(data->regmap, DPS310_TMP_BASE, val, sizeof(val));
495	if (rc < 0)
496		return rc;
497
498	raw = (val[0] << 16) | (val[1] << 8) | val[2];
499	data->temp_raw = sign_extend32(raw, 23);
500
501	return 0;
502}
503
504static int dps310_read_temp_raw(struct dps310_data *data)
505{
506	int rc;
507	int rate;
508	int timeout;
509
510	if (mutex_lock_interruptible(&data->lock))
511		return -EINTR;
512
513	rate = dps310_get_temp_samp_freq(data);
514	timeout = DPS310_POLL_TIMEOUT_US(rate);
515
516	/* Poll for sensor readiness; base the timeout upon the sample rate. */
517	rc = dps310_ready(data, DPS310_TMP_RDY, timeout);
518	if (rc)
519		goto done;
520
521	rc = dps310_read_temp_ready(data);
522
523done:
524	mutex_unlock(&data->lock);
525	return rc;
526}
527
528static bool dps310_is_writeable_reg(struct device *dev, unsigned int reg)
529{
530	switch (reg) {
531	case DPS310_PRS_CFG:
532	case DPS310_TMP_CFG:
533	case DPS310_MEAS_CFG:
534	case DPS310_CFG_REG:
535	case DPS310_RESET:
536	/* No documentation available on the registers below */
537	case 0x0e:
538	case 0x0f:
539	case 0x62:
540		return true;
541	default:
542		return false;
543	}
544}
545
546static bool dps310_is_volatile_reg(struct device *dev, unsigned int reg)
547{
548	switch (reg) {
549	case DPS310_PRS_B0:
550	case DPS310_PRS_B1:
551	case DPS310_PRS_B2:
552	case DPS310_TMP_B0:
553	case DPS310_TMP_B1:
554	case DPS310_TMP_B2:
555	case DPS310_MEAS_CFG:
556	case 0x32:	/* No documentation available on this register */
557		return true;
558	default:
559		return false;
560	}
561}
562
563static int dps310_write_raw(struct iio_dev *iio,
564			    struct iio_chan_spec const *chan, int val,
565			    int val2, long mask)
566{
567	int rc;
568	struct dps310_data *data = iio_priv(iio);
569
570	if (mutex_lock_interruptible(&data->lock))
571		return -EINTR;
572
573	switch (mask) {
574	case IIO_CHAN_INFO_SAMP_FREQ:
575		switch (chan->type) {
576		case IIO_PRESSURE:
577			rc = dps310_set_pres_samp_freq(data, val);
578			break;
579
580		case IIO_TEMP:
581			rc = dps310_set_temp_samp_freq(data, val);
582			break;
583
584		default:
585			rc = -EINVAL;
586			break;
587		}
588		break;
589
590	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
591		switch (chan->type) {
592		case IIO_PRESSURE:
593			rc = dps310_set_pres_precision(data, val);
594			break;
595
596		case IIO_TEMP:
597			rc = dps310_set_temp_precision(data, val);
598			break;
599
600		default:
601			rc = -EINVAL;
602			break;
603		}
604		break;
605
606	default:
607		rc = -EINVAL;
608		break;
609	}
610
611	mutex_unlock(&data->lock);
612	return rc;
613}
614
615static int dps310_calculate_pressure(struct dps310_data *data)
616{
617	int i;
618	int rc;
619	int t_ready;
620	int kpi = dps310_get_pres_k(data);
621	int kti = dps310_get_temp_k(data);
622	s64 rem = 0ULL;
623	s64 pressure = 0ULL;
624	s64 p;
625	s64 t;
626	s64 denoms[7];
627	s64 nums[7];
628	s64 rems[7];
629	s64 kp;
630	s64 kt;
631
632	if (kpi < 0)
633		return kpi;
634
635	if (kti < 0)
636		return kti;
637
638	kp = (s64)kpi;
639	kt = (s64)kti;
640
641	/* Refresh temp if it's ready, otherwise just use the latest value */
642	if (mutex_trylock(&data->lock)) {
643		rc = regmap_read(data->regmap, DPS310_MEAS_CFG, &t_ready);
644		if (rc >= 0 && t_ready & DPS310_TMP_RDY)
645			dps310_read_temp_ready(data);
646
647		mutex_unlock(&data->lock);
648	}
649
650	p = (s64)data->pressure_raw;
651	t = (s64)data->temp_raw;
652
653	/* Section 4.9.1 of the DPS310 spec; algebra'd to avoid underflow */
654	nums[0] = (s64)data->c00;
655	denoms[0] = 1LL;
656	nums[1] = p * (s64)data->c10;
657	denoms[1] = kp;
658	nums[2] = p * p * (s64)data->c20;
659	denoms[2] = kp * kp;
660	nums[3] = p * p * p * (s64)data->c30;
661	denoms[3] = kp * kp * kp;
662	nums[4] = t * (s64)data->c01;
663	denoms[4] = kt;
664	nums[5] = t * p * (s64)data->c11;
665	denoms[5] = kp * kt;
666	nums[6] = t * p * p * (s64)data->c21;
667	denoms[6] = kp * kp * kt;
668
669	/* Kernel lacks a div64_s64_rem function; denoms are all positive */
670	for (i = 0; i < 7; ++i) {
671		u64 irem;
672
673		if (nums[i] < 0LL) {
674			pressure -= div64_u64_rem(-nums[i], denoms[i], &irem);
675			rems[i] = -irem;
676		} else {
677			pressure += div64_u64_rem(nums[i], denoms[i], &irem);
678			rems[i] = (s64)irem;
679		}
680	}
681
682	/* Increase precision and calculate the remainder sum */
683	for (i = 0; i < 7; ++i)
684		rem += div64_s64((s64)rems[i] * 1000000000LL, denoms[i]);
685
686	pressure += div_s64(rem, 1000000000LL);
687	if (pressure < 0LL)
688		return -ERANGE;
689
690	return (int)min_t(s64, pressure, INT_MAX);
691}
692
693static int dps310_read_pressure(struct dps310_data *data, int *val, int *val2,
694				long mask)
695{
696	int rc;
697
698	switch (mask) {
699	case IIO_CHAN_INFO_SAMP_FREQ:
700		rc = dps310_get_pres_samp_freq(data);
701		if (rc < 0)
702			return rc;
703
704		*val = rc;
705		return IIO_VAL_INT;
706
707	case IIO_CHAN_INFO_PROCESSED:
708		rc = dps310_read_pres_raw(data);
709		if (rc)
710			return rc;
711
712		rc = dps310_calculate_pressure(data);
713		if (rc < 0)
714			return rc;
715
716		*val = rc;
717		*val2 = 1000; /* Convert Pa to KPa per IIO ABI */
718		return IIO_VAL_FRACTIONAL;
719
720	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
721		rc = dps310_get_pres_precision(data);
722		if (rc < 0)
723			return rc;
724
725		*val = rc;
726		return IIO_VAL_INT;
727
728	default:
729		return -EINVAL;
730	}
731}
732
733static int dps310_calculate_temp(struct dps310_data *data)
734{
735	s64 c0;
736	s64 t;
737	int kt = dps310_get_temp_k(data);
738
739	if (kt < 0)
740		return kt;
741
742	/* Obtain inverse-scaled offset */
743	c0 = div_s64((s64)kt * (s64)data->c0, 2);
744
745	/* Add the offset to the unscaled temperature */
746	t = c0 + ((s64)data->temp_raw * (s64)data->c1);
747
748	/* Convert to milliCelsius and scale the temperature */
749	return (int)div_s64(t * 1000LL, kt);
750}
751
752static int dps310_read_temp(struct dps310_data *data, int *val, int *val2,
753			    long mask)
754{
755	int rc;
756
757	switch (mask) {
758	case IIO_CHAN_INFO_SAMP_FREQ:
759		rc = dps310_get_temp_samp_freq(data);
760		if (rc < 0)
761			return rc;
762
763		*val = rc;
764		return IIO_VAL_INT;
765
766	case IIO_CHAN_INFO_PROCESSED:
767		rc = dps310_read_temp_raw(data);
768		if (rc)
769			return rc;
770
771		rc = dps310_calculate_temp(data);
772		if (rc < 0)
773			return rc;
774
775		*val = rc;
776		return IIO_VAL_INT;
777
778	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
779		rc = dps310_get_temp_precision(data);
780		if (rc < 0)
781			return rc;
782
783		*val = rc;
784		return IIO_VAL_INT;
785
786	default:
787		return -EINVAL;
788	}
789}
790
791static int dps310_read_raw(struct iio_dev *iio,
792			   struct iio_chan_spec const *chan,
793			   int *val, int *val2, long mask)
794{
795	struct dps310_data *data = iio_priv(iio);
796
797	switch (chan->type) {
798	case IIO_PRESSURE:
799		return dps310_read_pressure(data, val, val2, mask);
800
801	case IIO_TEMP:
802		return dps310_read_temp(data, val, val2, mask);
803
804	default:
805		return -EINVAL;
806	}
807}
808
809static void dps310_reset(void *action_data)
810{
811	struct dps310_data *data = action_data;
812
813	dps310_reset_wait(data);
814}
815
816static const struct regmap_config dps310_regmap_config = {
817	.reg_bits = 8,
818	.val_bits = 8,
819	.writeable_reg = dps310_is_writeable_reg,
820	.volatile_reg = dps310_is_volatile_reg,
821	.cache_type = REGCACHE_RBTREE,
822	.max_register = 0x62, /* No documentation available on this register */
823};
824
825static const struct iio_info dps310_info = {
826	.read_raw = dps310_read_raw,
827	.write_raw = dps310_write_raw,
828};
829
830static int dps310_probe(struct i2c_client *client)
831{
832	const struct i2c_device_id *id = i2c_client_get_device_id(client);
833	struct dps310_data *data;
834	struct iio_dev *iio;
835	int rc;
836
837	iio = devm_iio_device_alloc(&client->dev,  sizeof(*data));
838	if (!iio)
839		return -ENOMEM;
840
841	data = iio_priv(iio);
842	data->client = client;
843	mutex_init(&data->lock);
844
845	iio->name = id->name;
846	iio->channels = dps310_channels;
847	iio->num_channels = ARRAY_SIZE(dps310_channels);
848	iio->info = &dps310_info;
849	iio->modes = INDIO_DIRECT_MODE;
850
851	data->regmap = devm_regmap_init_i2c(client, &dps310_regmap_config);
852	if (IS_ERR(data->regmap))
853		return PTR_ERR(data->regmap);
854
855	/* Register to run the device reset when the device is removed */
856	rc = devm_add_action_or_reset(&client->dev, dps310_reset, data);
857	if (rc)
858		return rc;
859
860	rc = dps310_startup(data);
861	if (rc)
862		return rc;
863
864	rc = devm_iio_device_register(&client->dev, iio);
865	if (rc)
866		return rc;
867
868	i2c_set_clientdata(client, iio);
869
870	return 0;
871}
872
873static const struct i2c_device_id dps310_id[] = {
874	{ DPS310_DEV_NAME, 0 },
875	{}
876};
877MODULE_DEVICE_TABLE(i2c, dps310_id);
878
879static const struct acpi_device_id dps310_acpi_match[] = {
880	{ "IFX3100" },
881	{}
882};
883MODULE_DEVICE_TABLE(acpi, dps310_acpi_match);
884
885static struct i2c_driver dps310_driver = {
886	.driver = {
887		.name = DPS310_DEV_NAME,
888		.acpi_match_table = dps310_acpi_match,
889	},
890	.probe = dps310_probe,
891	.id_table = dps310_id,
892};
893module_i2c_driver(dps310_driver);
894
895MODULE_AUTHOR("Joel Stanley <joel@jms.id.au>");
896MODULE_DESCRIPTION("Infineon DPS310 pressure and temperature sensor");
897MODULE_LICENSE("GPL v2");
898