1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for NXP FXAS21002C Gyroscope - Core
4  *
5  * Copyright (C) 2019 Linaro Ltd.
6  */
7 
8 #include <linux/interrupt.h>
9 #include <linux/module.h>
10 #include <linux/of_irq.h>
11 #include <linux/pm.h>
12 #include <linux/pm_runtime.h>
13 #include <linux/regmap.h>
14 #include <linux/regulator/consumer.h>
15 
16 #include <linux/iio/events.h>
17 #include <linux/iio/iio.h>
18 #include <linux/iio/buffer.h>
19 #include <linux/iio/sysfs.h>
20 #include <linux/iio/trigger.h>
21 #include <linux/iio/trigger_consumer.h>
22 #include <linux/iio/triggered_buffer.h>
23 
24 #include "fxas21002c.h"
25 
26 #define FXAS21002C_CHIP_ID_1	0xD6
27 #define FXAS21002C_CHIP_ID_2	0xD7
28 
29 enum fxas21002c_mode_state {
30 	FXAS21002C_MODE_STANDBY,
31 	FXAS21002C_MODE_READY,
32 	FXAS21002C_MODE_ACTIVE,
33 };
34 
35 #define FXAS21002C_STANDBY_ACTIVE_TIME_MS	62
36 #define FXAS21002C_READY_ACTIVE_TIME_MS		7
37 
38 #define FXAS21002C_ODR_LIST_MAX		10
39 
40 #define FXAS21002C_SCALE_FRACTIONAL	32
41 #define FXAS21002C_RANGE_LIMIT_DOUBLE	2000
42 
43 #define FXAS21002C_AXIS_TO_REG(axis) (FXAS21002C_REG_OUT_X_MSB + ((axis) * 2))
44 
45 static const int fxas21002c_odr_values[] = {
46 	800, 400, 200, 100, 50, 25, 12, 12
47 };
48 
49 /*
50  * These values are taken from the low-pass filter cutoff frequency calculated
51  * ODR * 0.lpf_values. So, for ODR = 800Hz with a lpf value = 0.32
52  * => LPF cutoff frequency = 800 * 0.32 = 256 Hz
53  */
54 static const int fxas21002c_lpf_values[] = {
55 	32, 16, 8
56 };
57 
58 /*
59  * These values are taken from the high-pass filter cutoff frequency calculated
60  * ODR * 0.0hpf_values. So, for ODR = 800Hz with a hpf value = 0.018750
61  * => HPF cutoff frequency = 800 * 0.018750 = 15 Hz
62  */
63 static const int fxas21002c_hpf_values[] = {
64 	18750, 9625, 4875, 2475
65 };
66 
67 static const int fxas21002c_range_values[] = {
68 	4000, 2000, 1000, 500, 250
69 };
70 
71 struct fxas21002c_data {
72 	u8 chip_id;
73 	enum fxas21002c_mode_state mode;
74 	enum fxas21002c_mode_state prev_mode;
75 
76 	struct mutex lock;		/* serialize data access */
77 	struct regmap *regmap;
78 	struct regmap_field *regmap_fields[F_MAX_FIELDS];
79 	struct iio_trigger *dready_trig;
80 	s64 timestamp;
81 	int irq;
82 
83 	struct regulator *vdd;
84 	struct regulator *vddio;
85 
86 	/*
87 	 * DMA (thus cache coherency maintenance) requires the
88 	 * transfer buffers to live in their own cache lines.
89 	 */
90 	s16 buffer[8] ____cacheline_aligned;
91 };
92 
93 enum fxas21002c_channel_index {
94 	CHANNEL_SCAN_INDEX_X,
95 	CHANNEL_SCAN_INDEX_Y,
96 	CHANNEL_SCAN_INDEX_Z,
97 	CHANNEL_SCAN_MAX,
98 };
99 
100 static int fxas21002c_odr_hz_from_value(struct fxas21002c_data *data, u8 value)
101 {
102 	int odr_value_max = ARRAY_SIZE(fxas21002c_odr_values) - 1;
103 
104 	value = min_t(u8, value, odr_value_max);
105 
106 	return fxas21002c_odr_values[value];
107 }
108 
109 static int fxas21002c_odr_value_from_hz(struct fxas21002c_data *data,
110 					unsigned int hz)
111 {
112 	int odr_table_size = ARRAY_SIZE(fxas21002c_odr_values);
113 	int i;
114 
115 	for (i = 0; i < odr_table_size; i++)
116 		if (fxas21002c_odr_values[i] == hz)
117 			return i;
118 
119 	return -EINVAL;
120 }
121 
122 static int fxas21002c_lpf_bw_from_value(struct fxas21002c_data *data, u8 value)
123 {
124 	int lpf_value_max = ARRAY_SIZE(fxas21002c_lpf_values) - 1;
125 
126 	value = min_t(u8, value, lpf_value_max);
127 
128 	return fxas21002c_lpf_values[value];
129 }
130 
131 static int fxas21002c_lpf_value_from_bw(struct fxas21002c_data *data,
132 					unsigned int hz)
133 {
134 	int lpf_table_size = ARRAY_SIZE(fxas21002c_lpf_values);
135 	int i;
136 
137 	for (i = 0; i < lpf_table_size; i++)
138 		if (fxas21002c_lpf_values[i] == hz)
139 			return i;
140 
141 	return -EINVAL;
142 }
143 
144 static int fxas21002c_hpf_sel_from_value(struct fxas21002c_data *data, u8 value)
145 {
146 	int hpf_value_max = ARRAY_SIZE(fxas21002c_hpf_values) - 1;
147 
148 	value = min_t(u8, value, hpf_value_max);
149 
150 	return fxas21002c_hpf_values[value];
151 }
152 
153 static int fxas21002c_hpf_value_from_sel(struct fxas21002c_data *data,
154 					 unsigned int hz)
155 {
156 	int hpf_table_size = ARRAY_SIZE(fxas21002c_hpf_values);
157 	int i;
158 
159 	for (i = 0; i < hpf_table_size; i++)
160 		if (fxas21002c_hpf_values[i] == hz)
161 			return i;
162 
163 	return -EINVAL;
164 }
165 
166 static int fxas21002c_range_fs_from_value(struct fxas21002c_data *data,
167 					  u8 value)
168 {
169 	int range_value_max = ARRAY_SIZE(fxas21002c_range_values) - 1;
170 	unsigned int fs_double;
171 	int ret;
172 
173 	/* We need to check if FS_DOUBLE is enabled to offset the value */
174 	ret = regmap_field_read(data->regmap_fields[F_FS_DOUBLE], &fs_double);
175 	if (ret < 0)
176 		return ret;
177 
178 	if (!fs_double)
179 		value += 1;
180 
181 	value = min_t(u8, value, range_value_max);
182 
183 	return fxas21002c_range_values[value];
184 }
185 
186 static int fxas21002c_range_value_from_fs(struct fxas21002c_data *data,
187 					  unsigned int range)
188 {
189 	int range_table_size = ARRAY_SIZE(fxas21002c_range_values);
190 	bool found = false;
191 	int fs_double = 0;
192 	int ret;
193 	int i;
194 
195 	for (i = 0; i < range_table_size; i++)
196 		if (fxas21002c_range_values[i] == range) {
197 			found = true;
198 			break;
199 		}
200 
201 	if (!found)
202 		return -EINVAL;
203 
204 	if (range > FXAS21002C_RANGE_LIMIT_DOUBLE)
205 		fs_double = 1;
206 
207 	ret = regmap_field_write(data->regmap_fields[F_FS_DOUBLE], fs_double);
208 	if (ret < 0)
209 		return ret;
210 
211 	return i;
212 }
213 
214 static int fxas21002c_mode_get(struct fxas21002c_data *data)
215 {
216 	unsigned int active;
217 	unsigned int ready;
218 	int ret;
219 
220 	ret = regmap_field_read(data->regmap_fields[F_ACTIVE], &active);
221 	if (ret < 0)
222 		return ret;
223 	if (active)
224 		return FXAS21002C_MODE_ACTIVE;
225 
226 	ret = regmap_field_read(data->regmap_fields[F_READY], &ready);
227 	if (ret < 0)
228 		return ret;
229 	if (ready)
230 		return FXAS21002C_MODE_READY;
231 
232 	return FXAS21002C_MODE_STANDBY;
233 }
234 
235 static int fxas21002c_mode_set(struct fxas21002c_data *data,
236 			       enum fxas21002c_mode_state mode)
237 {
238 	int ret;
239 
240 	if (mode == data->mode)
241 		return 0;
242 
243 	if (mode == FXAS21002C_MODE_READY)
244 		ret = regmap_field_write(data->regmap_fields[F_READY], 1);
245 	else
246 		ret = regmap_field_write(data->regmap_fields[F_READY], 0);
247 	if (ret < 0)
248 		return ret;
249 
250 	if (mode == FXAS21002C_MODE_ACTIVE)
251 		ret = regmap_field_write(data->regmap_fields[F_ACTIVE], 1);
252 	else
253 		ret = regmap_field_write(data->regmap_fields[F_ACTIVE], 0);
254 	if (ret < 0)
255 		return ret;
256 
257 	/* if going to active wait the setup times */
258 	if (mode == FXAS21002C_MODE_ACTIVE &&
259 	    data->mode == FXAS21002C_MODE_STANDBY)
260 		msleep_interruptible(FXAS21002C_STANDBY_ACTIVE_TIME_MS);
261 
262 	if (data->mode == FXAS21002C_MODE_READY)
263 		msleep_interruptible(FXAS21002C_READY_ACTIVE_TIME_MS);
264 
265 	data->prev_mode = data->mode;
266 	data->mode = mode;
267 
268 	return ret;
269 }
270 
271 static int fxas21002c_write(struct fxas21002c_data *data,
272 			    enum fxas21002c_fields field, int bits)
273 {
274 	int actual_mode;
275 	int ret;
276 
277 	mutex_lock(&data->lock);
278 
279 	actual_mode = fxas21002c_mode_get(data);
280 	if (actual_mode < 0) {
281 		ret = actual_mode;
282 		goto out_unlock;
283 	}
284 
285 	ret = fxas21002c_mode_set(data, FXAS21002C_MODE_READY);
286 	if (ret < 0)
287 		goto out_unlock;
288 
289 	ret = regmap_field_write(data->regmap_fields[field], bits);
290 	if (ret < 0)
291 		goto out_unlock;
292 
293 	ret = fxas21002c_mode_set(data, data->prev_mode);
294 
295 out_unlock:
296 	mutex_unlock(&data->lock);
297 
298 	return ret;
299 }
300 
301 static int  fxas21002c_pm_get(struct fxas21002c_data *data)
302 {
303 	struct device *dev = regmap_get_device(data->regmap);
304 	int ret;
305 
306 	ret = pm_runtime_get_sync(dev);
307 	if (ret < 0)
308 		pm_runtime_put_noidle(dev);
309 
310 	return ret;
311 }
312 
313 static int  fxas21002c_pm_put(struct fxas21002c_data *data)
314 {
315 	struct device *dev = regmap_get_device(data->regmap);
316 
317 	pm_runtime_mark_last_busy(dev);
318 
319 	return pm_runtime_put_autosuspend(dev);
320 }
321 
322 static int fxas21002c_temp_get(struct fxas21002c_data *data, int *val)
323 {
324 	struct device *dev = regmap_get_device(data->regmap);
325 	unsigned int temp;
326 	int ret;
327 
328 	mutex_lock(&data->lock);
329 	ret = fxas21002c_pm_get(data);
330 	if (ret < 0)
331 		goto data_unlock;
332 
333 	ret = regmap_field_read(data->regmap_fields[F_TEMP], &temp);
334 	if (ret < 0) {
335 		dev_err(dev, "failed to read temp: %d\n", ret);
336 		goto data_unlock;
337 	}
338 
339 	*val = sign_extend32(temp, 7);
340 
341 	ret = fxas21002c_pm_put(data);
342 	if (ret < 0)
343 		goto data_unlock;
344 
345 	ret = IIO_VAL_INT;
346 
347 data_unlock:
348 	mutex_unlock(&data->lock);
349 
350 	return ret;
351 }
352 
353 static int fxas21002c_axis_get(struct fxas21002c_data *data,
354 			       int index, int *val)
355 {
356 	struct device *dev = regmap_get_device(data->regmap);
357 	__be16 axis_be;
358 	int ret;
359 
360 	mutex_lock(&data->lock);
361 	ret = fxas21002c_pm_get(data);
362 	if (ret < 0)
363 		goto data_unlock;
364 
365 	ret = regmap_bulk_read(data->regmap, FXAS21002C_AXIS_TO_REG(index),
366 			       &axis_be, sizeof(axis_be));
367 	if (ret < 0) {
368 		dev_err(dev, "failed to read axis: %d: %d\n", index, ret);
369 		goto data_unlock;
370 	}
371 
372 	*val = sign_extend32(be16_to_cpu(axis_be), 15);
373 
374 	ret = fxas21002c_pm_put(data);
375 	if (ret < 0)
376 		goto data_unlock;
377 
378 	ret = IIO_VAL_INT;
379 
380 data_unlock:
381 	mutex_unlock(&data->lock);
382 
383 	return ret;
384 }
385 
386 static int fxas21002c_odr_get(struct fxas21002c_data *data, int *odr)
387 {
388 	unsigned int odr_bits;
389 	int ret;
390 
391 	mutex_lock(&data->lock);
392 	ret = regmap_field_read(data->regmap_fields[F_DR], &odr_bits);
393 	if (ret < 0)
394 		goto data_unlock;
395 
396 	*odr = fxas21002c_odr_hz_from_value(data, odr_bits);
397 
398 	ret = IIO_VAL_INT;
399 
400 data_unlock:
401 	mutex_unlock(&data->lock);
402 
403 	return ret;
404 }
405 
406 static int fxas21002c_odr_set(struct fxas21002c_data *data, int odr)
407 {
408 	int odr_bits;
409 
410 	odr_bits = fxas21002c_odr_value_from_hz(data, odr);
411 	if (odr_bits < 0)
412 		return odr_bits;
413 
414 	return fxas21002c_write(data, F_DR, odr_bits);
415 }
416 
417 static int fxas21002c_lpf_get(struct fxas21002c_data *data, int *val2)
418 {
419 	unsigned int bw_bits;
420 	int ret;
421 
422 	mutex_lock(&data->lock);
423 	ret = regmap_field_read(data->regmap_fields[F_BW], &bw_bits);
424 	if (ret < 0)
425 		goto data_unlock;
426 
427 	*val2 = fxas21002c_lpf_bw_from_value(data, bw_bits) * 10000;
428 
429 	ret = IIO_VAL_INT_PLUS_MICRO;
430 
431 data_unlock:
432 	mutex_unlock(&data->lock);
433 
434 	return ret;
435 }
436 
437 static int fxas21002c_lpf_set(struct fxas21002c_data *data, int bw)
438 {
439 	int bw_bits;
440 	int odr;
441 	int ret;
442 
443 	bw_bits = fxas21002c_lpf_value_from_bw(data, bw);
444 	if (bw_bits < 0)
445 		return bw_bits;
446 
447 	/*
448 	 * From table 33 of the device spec, for ODR = 25Hz and 12.5 value 0.08
449 	 * is not allowed and for ODR = 12.5 value 0.16 is also not allowed
450 	 */
451 	ret = fxas21002c_odr_get(data, &odr);
452 	if (ret < 0)
453 		return -EINVAL;
454 
455 	if ((odr == 25 && bw_bits > 0x01) || (odr == 12 && bw_bits > 0))
456 		return -EINVAL;
457 
458 	return fxas21002c_write(data, F_BW, bw_bits);
459 }
460 
461 static int fxas21002c_hpf_get(struct fxas21002c_data *data, int *val2)
462 {
463 	unsigned int sel_bits;
464 	int ret;
465 
466 	mutex_lock(&data->lock);
467 	ret = regmap_field_read(data->regmap_fields[F_SEL], &sel_bits);
468 	if (ret < 0)
469 		goto data_unlock;
470 
471 	*val2 = fxas21002c_hpf_sel_from_value(data, sel_bits);
472 
473 	ret = IIO_VAL_INT_PLUS_MICRO;
474 
475 data_unlock:
476 	mutex_unlock(&data->lock);
477 
478 	return ret;
479 }
480 
481 static int fxas21002c_hpf_set(struct fxas21002c_data *data, int sel)
482 {
483 	int sel_bits;
484 
485 	sel_bits = fxas21002c_hpf_value_from_sel(data, sel);
486 	if (sel_bits < 0)
487 		return sel_bits;
488 
489 	return fxas21002c_write(data, F_SEL, sel_bits);
490 }
491 
492 static int fxas21002c_scale_get(struct fxas21002c_data *data, int *val)
493 {
494 	int fs_bits;
495 	int scale;
496 	int ret;
497 
498 	mutex_lock(&data->lock);
499 	ret = regmap_field_read(data->regmap_fields[F_FS], &fs_bits);
500 	if (ret < 0)
501 		goto data_unlock;
502 
503 	scale = fxas21002c_range_fs_from_value(data, fs_bits);
504 	if (scale < 0) {
505 		ret = scale;
506 		goto data_unlock;
507 	}
508 
509 	*val = scale;
510 
511 data_unlock:
512 	mutex_unlock(&data->lock);
513 
514 	return ret;
515 }
516 
517 static int fxas21002c_scale_set(struct fxas21002c_data *data, int range)
518 {
519 	int fs_bits;
520 
521 	fs_bits = fxas21002c_range_value_from_fs(data, range);
522 	if (fs_bits < 0)
523 		return fs_bits;
524 
525 	return fxas21002c_write(data, F_FS, fs_bits);
526 }
527 
528 static int fxas21002c_read_raw(struct iio_dev *indio_dev,
529 			       struct iio_chan_spec const *chan, int *val,
530 			       int *val2, long mask)
531 {
532 	struct fxas21002c_data *data = iio_priv(indio_dev);
533 	int ret;
534 
535 	switch (mask) {
536 	case IIO_CHAN_INFO_RAW:
537 		switch (chan->type) {
538 		case IIO_TEMP:
539 			return fxas21002c_temp_get(data, val);
540 		case IIO_ANGL_VEL:
541 			return fxas21002c_axis_get(data, chan->scan_index, val);
542 		default:
543 			return -EINVAL;
544 		}
545 	case IIO_CHAN_INFO_SCALE:
546 		switch (chan->type) {
547 		case IIO_ANGL_VEL:
548 			*val2 = FXAS21002C_SCALE_FRACTIONAL;
549 			ret = fxas21002c_scale_get(data, val);
550 			if (ret < 0)
551 				return ret;
552 
553 			return IIO_VAL_FRACTIONAL;
554 		default:
555 			return -EINVAL;
556 		}
557 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
558 		*val = 0;
559 		return fxas21002c_lpf_get(data, val2);
560 	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
561 		*val = 0;
562 		return fxas21002c_hpf_get(data, val2);
563 	case IIO_CHAN_INFO_SAMP_FREQ:
564 		*val2 = 0;
565 		return fxas21002c_odr_get(data, val);
566 	default:
567 		return -EINVAL;
568 	}
569 }
570 
571 static int fxas21002c_write_raw(struct iio_dev *indio_dev,
572 				struct iio_chan_spec const *chan, int val,
573 				int val2, long mask)
574 {
575 	struct fxas21002c_data *data = iio_priv(indio_dev);
576 	int range;
577 
578 	switch (mask) {
579 	case IIO_CHAN_INFO_SAMP_FREQ:
580 		if (val2)
581 			return -EINVAL;
582 
583 		return fxas21002c_odr_set(data, val);
584 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
585 		if (val)
586 			return -EINVAL;
587 
588 		val2 = val2 / 10000;
589 		return fxas21002c_lpf_set(data, val2);
590 	case IIO_CHAN_INFO_SCALE:
591 		switch (chan->type) {
592 		case IIO_ANGL_VEL:
593 			range = (((val * 1000 + val2 / 1000) *
594 				  FXAS21002C_SCALE_FRACTIONAL) / 1000);
595 			return fxas21002c_scale_set(data, range);
596 		default:
597 			return -EINVAL;
598 		}
599 	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
600 		return fxas21002c_hpf_set(data, val2);
601 	default:
602 		return -EINVAL;
603 	}
604 }
605 
606 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("12.5 25 50 100 200 400 800");
607 
608 static IIO_CONST_ATTR(in_anglvel_filter_low_pass_3db_frequency_available,
609 		      "0.32 0.16 0.08");
610 
611 static IIO_CONST_ATTR(in_anglvel_filter_high_pass_3db_frequency_available,
612 		      "0.018750 0.009625 0.004875 0.002475");
613 
614 static IIO_CONST_ATTR(in_anglvel_scale_available,
615 		      "125.0 62.5 31.25 15.625 7.8125");
616 
617 static struct attribute *fxas21002c_attributes[] = {
618 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
619 	&iio_const_attr_in_anglvel_filter_low_pass_3db_frequency_available.dev_attr.attr,
620 	&iio_const_attr_in_anglvel_filter_high_pass_3db_frequency_available.dev_attr.attr,
621 	&iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
622 	NULL,
623 };
624 
625 static const struct attribute_group fxas21002c_attrs_group = {
626 	.attrs = fxas21002c_attributes,
627 };
628 
629 #define FXAS21002C_CHANNEL(_axis) {					\
630 	.type = IIO_ANGL_VEL,						\
631 	.modified = 1,							\
632 	.channel2 = IIO_MOD_##_axis,					\
633 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
634 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
635 		BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) |	\
636 		BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY) |	\
637 		BIT(IIO_CHAN_INFO_SAMP_FREQ),				\
638 	.scan_index = CHANNEL_SCAN_INDEX_##_axis,			\
639 	.scan_type = {							\
640 		.sign = 's',						\
641 		.realbits = 16,						\
642 		.storagebits = 16,					\
643 		.endianness = IIO_BE,					\
644 	},								\
645 }
646 
647 static const struct iio_chan_spec fxas21002c_channels[] = {
648 	{
649 		.type = IIO_TEMP,
650 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
651 		.scan_index = -1,
652 	},
653 	FXAS21002C_CHANNEL(X),
654 	FXAS21002C_CHANNEL(Y),
655 	FXAS21002C_CHANNEL(Z),
656 };
657 
658 static const struct iio_info fxas21002c_info = {
659 	.attrs			= &fxas21002c_attrs_group,
660 	.read_raw		= &fxas21002c_read_raw,
661 	.write_raw		= &fxas21002c_write_raw,
662 };
663 
664 static irqreturn_t fxas21002c_trigger_handler(int irq, void *p)
665 {
666 	struct iio_poll_func *pf = p;
667 	struct iio_dev *indio_dev = pf->indio_dev;
668 	struct fxas21002c_data *data = iio_priv(indio_dev);
669 	int ret;
670 
671 	mutex_lock(&data->lock);
672 	ret = regmap_bulk_read(data->regmap, FXAS21002C_REG_OUT_X_MSB,
673 			       data->buffer, CHANNEL_SCAN_MAX * sizeof(s16));
674 	if (ret < 0)
675 		goto out_unlock;
676 
677 	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
678 					   data->timestamp);
679 
680 out_unlock:
681 	mutex_unlock(&data->lock);
682 
683 	iio_trigger_notify_done(indio_dev->trig);
684 
685 	return IRQ_HANDLED;
686 }
687 
688 static int fxas21002c_chip_init(struct fxas21002c_data *data)
689 {
690 	struct device *dev = regmap_get_device(data->regmap);
691 	unsigned int chip_id;
692 	int ret;
693 
694 	ret = regmap_field_read(data->regmap_fields[F_WHO_AM_I], &chip_id);
695 	if (ret < 0)
696 		return ret;
697 
698 	if (chip_id != FXAS21002C_CHIP_ID_1 &&
699 	    chip_id != FXAS21002C_CHIP_ID_2) {
700 		dev_err(dev, "chip id 0x%02x is not supported\n", chip_id);
701 		return -EINVAL;
702 	}
703 
704 	data->chip_id = chip_id;
705 
706 	ret = fxas21002c_mode_set(data, FXAS21002C_MODE_STANDBY);
707 	if (ret < 0)
708 		return ret;
709 
710 	/* Set ODR to 200HZ as default */
711 	ret = fxas21002c_odr_set(data, 200);
712 	if (ret < 0)
713 		dev_err(dev, "failed to set ODR: %d\n", ret);
714 
715 	return ret;
716 }
717 
718 static int fxas21002c_data_rdy_trigger_set_state(struct iio_trigger *trig,
719 						 bool state)
720 {
721 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
722 	struct fxas21002c_data *data = iio_priv(indio_dev);
723 
724 	return regmap_field_write(data->regmap_fields[F_INT_EN_DRDY], state);
725 }
726 
727 static const struct iio_trigger_ops fxas21002c_trigger_ops = {
728 	.set_trigger_state = &fxas21002c_data_rdy_trigger_set_state,
729 };
730 
731 static irqreturn_t fxas21002c_data_rdy_handler(int irq, void *private)
732 {
733 	struct iio_dev *indio_dev = private;
734 	struct fxas21002c_data *data = iio_priv(indio_dev);
735 
736 	data->timestamp = iio_get_time_ns(indio_dev);
737 
738 	return IRQ_WAKE_THREAD;
739 }
740 
741 static irqreturn_t fxas21002c_data_rdy_thread(int irq, void *private)
742 {
743 	struct iio_dev *indio_dev = private;
744 	struct fxas21002c_data *data = iio_priv(indio_dev);
745 	unsigned int data_ready;
746 	int ret;
747 
748 	ret = regmap_field_read(data->regmap_fields[F_SRC_DRDY], &data_ready);
749 	if (ret < 0)
750 		return IRQ_NONE;
751 
752 	if (!data_ready)
753 		return IRQ_NONE;
754 
755 	iio_trigger_poll_chained(data->dready_trig);
756 
757 	return IRQ_HANDLED;
758 }
759 
760 static int fxas21002c_trigger_probe(struct fxas21002c_data *data)
761 {
762 	struct device *dev = regmap_get_device(data->regmap);
763 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
764 	struct device_node *np = indio_dev->dev.of_node;
765 	unsigned long irq_trig;
766 	bool irq_open_drain;
767 	int irq1;
768 	int ret;
769 
770 	if (!data->irq)
771 		return 0;
772 
773 	irq1 = of_irq_get_byname(np, "INT1");
774 
775 	if (irq1 == data->irq) {
776 		dev_info(dev, "using interrupt line INT1\n");
777 		ret = regmap_field_write(data->regmap_fields[F_INT_CFG_DRDY],
778 					 1);
779 		if (ret < 0)
780 			return ret;
781 	}
782 
783 	dev_info(dev, "using interrupt line INT2\n");
784 
785 	irq_open_drain = of_property_read_bool(np, "drive-open-drain");
786 
787 	data->dready_trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
788 						   indio_dev->name,
789 						   indio_dev->id);
790 	if (!data->dready_trig)
791 		return -ENOMEM;
792 
793 	irq_trig = irqd_get_trigger_type(irq_get_irq_data(data->irq));
794 
795 	if (irq_trig == IRQF_TRIGGER_RISING) {
796 		ret = regmap_field_write(data->regmap_fields[F_IPOL], 1);
797 		if (ret < 0)
798 			return ret;
799 	}
800 
801 	if (irq_open_drain)
802 		irq_trig |= IRQF_SHARED;
803 
804 	ret = devm_request_threaded_irq(dev, data->irq,
805 					fxas21002c_data_rdy_handler,
806 					fxas21002c_data_rdy_thread,
807 					irq_trig, "fxas21002c_data_ready",
808 					indio_dev);
809 	if (ret < 0)
810 		return ret;
811 
812 	data->dready_trig->dev.parent = dev;
813 	data->dready_trig->ops = &fxas21002c_trigger_ops;
814 	iio_trigger_set_drvdata(data->dready_trig, indio_dev);
815 
816 	return devm_iio_trigger_register(dev, data->dready_trig);
817 }
818 
819 static int fxas21002c_power_enable(struct fxas21002c_data *data)
820 {
821 	int ret;
822 
823 	ret = regulator_enable(data->vdd);
824 	if (ret < 0)
825 		return ret;
826 
827 	ret = regulator_enable(data->vddio);
828 	if (ret < 0) {
829 		regulator_disable(data->vdd);
830 		return ret;
831 	}
832 
833 	return 0;
834 }
835 
836 static void fxas21002c_power_disable(struct fxas21002c_data *data)
837 {
838 	regulator_disable(data->vdd);
839 	regulator_disable(data->vddio);
840 }
841 
842 static void fxas21002c_power_disable_action(void *_data)
843 {
844 	struct fxas21002c_data *data = _data;
845 
846 	fxas21002c_power_disable(data);
847 }
848 
849 static int fxas21002c_regulators_get(struct fxas21002c_data *data)
850 {
851 	struct device *dev = regmap_get_device(data->regmap);
852 
853 	data->vdd = devm_regulator_get(dev->parent, "vdd");
854 	if (IS_ERR(data->vdd))
855 		return PTR_ERR(data->vdd);
856 
857 	data->vddio = devm_regulator_get(dev->parent, "vddio");
858 
859 	return PTR_ERR_OR_ZERO(data->vddio);
860 }
861 
862 int fxas21002c_core_probe(struct device *dev, struct regmap *regmap, int irq,
863 			  const char *name)
864 {
865 	struct fxas21002c_data *data;
866 	struct iio_dev *indio_dev;
867 	struct regmap_field *f;
868 	int i;
869 	int ret;
870 
871 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
872 	if (!indio_dev)
873 		return -ENOMEM;
874 
875 	data = iio_priv(indio_dev);
876 	dev_set_drvdata(dev, indio_dev);
877 	data->irq = irq;
878 	data->regmap = regmap;
879 
880 	for (i = 0; i < F_MAX_FIELDS; i++) {
881 		f = devm_regmap_field_alloc(dev, data->regmap,
882 					    fxas21002c_reg_fields[i]);
883 		if (IS_ERR(f))
884 			return PTR_ERR(f);
885 
886 		data->regmap_fields[i] = f;
887 	}
888 
889 	mutex_init(&data->lock);
890 
891 	ret = fxas21002c_regulators_get(data);
892 	if (ret < 0)
893 		return ret;
894 
895 	ret = fxas21002c_power_enable(data);
896 	if (ret < 0)
897 		return ret;
898 
899 	ret = devm_add_action_or_reset(dev, fxas21002c_power_disable_action,
900 				       data);
901 	if (ret < 0)
902 		return ret;
903 
904 	ret = fxas21002c_chip_init(data);
905 	if (ret < 0)
906 		return ret;
907 
908 	indio_dev->dev.parent = dev;
909 	indio_dev->channels = fxas21002c_channels;
910 	indio_dev->num_channels = ARRAY_SIZE(fxas21002c_channels);
911 	indio_dev->name = name;
912 	indio_dev->modes = INDIO_DIRECT_MODE;
913 	indio_dev->info = &fxas21002c_info;
914 
915 	ret = fxas21002c_trigger_probe(data);
916 	if (ret < 0)
917 		return ret;
918 
919 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
920 					      fxas21002c_trigger_handler, NULL);
921 	if (ret < 0)
922 		return ret;
923 
924 	ret = pm_runtime_set_active(dev);
925 	if (ret)
926 		return ret;
927 
928 	pm_runtime_enable(dev);
929 	pm_runtime_set_autosuspend_delay(dev, 2000);
930 	pm_runtime_use_autosuspend(dev);
931 
932 	ret = iio_device_register(indio_dev);
933 	if (ret < 0)
934 		goto pm_disable;
935 
936 	return 0;
937 
938 pm_disable:
939 	pm_runtime_disable(dev);
940 	pm_runtime_set_suspended(dev);
941 	pm_runtime_put_noidle(dev);
942 
943 	return ret;
944 }
945 EXPORT_SYMBOL_GPL(fxas21002c_core_probe);
946 
947 void fxas21002c_core_remove(struct device *dev)
948 {
949 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
950 
951 	iio_device_unregister(indio_dev);
952 
953 	pm_runtime_disable(dev);
954 	pm_runtime_set_suspended(dev);
955 	pm_runtime_put_noidle(dev);
956 }
957 EXPORT_SYMBOL_GPL(fxas21002c_core_remove);
958 
959 static int __maybe_unused fxas21002c_suspend(struct device *dev)
960 {
961 	struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
962 
963 	fxas21002c_mode_set(data, FXAS21002C_MODE_STANDBY);
964 	fxas21002c_power_disable(data);
965 
966 	return 0;
967 }
968 
969 static int __maybe_unused fxas21002c_resume(struct device *dev)
970 {
971 	struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
972 	int ret;
973 
974 	ret = fxas21002c_power_enable(data);
975 	if (ret < 0)
976 		return ret;
977 
978 	return fxas21002c_mode_set(data, data->prev_mode);
979 }
980 
981 static int __maybe_unused fxas21002c_runtime_suspend(struct device *dev)
982 {
983 	struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
984 
985 	return fxas21002c_mode_set(data, FXAS21002C_MODE_READY);
986 }
987 
988 static int __maybe_unused fxas21002c_runtime_resume(struct device *dev)
989 {
990 	struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
991 
992 	return fxas21002c_mode_set(data, FXAS21002C_MODE_ACTIVE);
993 }
994 
995 const struct dev_pm_ops fxas21002c_pm_ops = {
996 	SET_SYSTEM_SLEEP_PM_OPS(fxas21002c_suspend, fxas21002c_resume)
997 	SET_RUNTIME_PM_OPS(fxas21002c_runtime_suspend,
998 			   fxas21002c_runtime_resume, NULL)
999 };
1000 EXPORT_SYMBOL_GPL(fxas21002c_pm_ops);
1001 
1002 MODULE_AUTHOR("Rui Miguel Silva <rui.silva@linaro.org>");
1003 MODULE_LICENSE("GPL v2");
1004 MODULE_DESCRIPTION("FXAS21002C Gyro driver");
1005