xref: /linux/drivers/iio/adc/ad7606.c (revision 17cfcb68af3bc7d5e8ae08779b1853310a2949f3)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * AD7606 SPI ADC driver
4  *
5  * Copyright 2011 Analog Devices Inc.
6  */
7 
8 #include <linux/delay.h>
9 #include <linux/device.h>
10 #include <linux/err.h>
11 #include <linux/gpio/consumer.h>
12 #include <linux/interrupt.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/regulator/consumer.h>
16 #include <linux/sched.h>
17 #include <linux/slab.h>
18 #include <linux/sysfs.h>
19 #include <linux/util_macros.h>
20 
21 #include <linux/iio/iio.h>
22 #include <linux/iio/buffer.h>
23 #include <linux/iio/sysfs.h>
24 #include <linux/iio/trigger.h>
25 #include <linux/iio/triggered_buffer.h>
26 #include <linux/iio/trigger_consumer.h>
27 
28 #include "ad7606.h"
29 
30 /*
31  * Scales are computed as 5000/32768 and 10000/32768 respectively,
32  * so that when applied to the raw values they provide mV values
33  */
34 static const unsigned int ad7606_scale_avail[2] = {
35 	152588, 305176
36 };
37 
38 
39 static const unsigned int ad7616_sw_scale_avail[3] = {
40 	76293, 152588, 305176
41 };
42 
43 static const unsigned int ad7606_oversampling_avail[7] = {
44 	1, 2, 4, 8, 16, 32, 64,
45 };
46 
47 static const unsigned int ad7616_oversampling_avail[8] = {
48 	1, 2, 4, 8, 16, 32, 64, 128,
49 };
50 
51 static int ad7606_reset(struct ad7606_state *st)
52 {
53 	if (st->gpio_reset) {
54 		gpiod_set_value(st->gpio_reset, 1);
55 		ndelay(100); /* t_reset >= 100ns */
56 		gpiod_set_value(st->gpio_reset, 0);
57 		return 0;
58 	}
59 
60 	return -ENODEV;
61 }
62 
63 static int ad7606_reg_access(struct iio_dev *indio_dev,
64 			     unsigned int reg,
65 			     unsigned int writeval,
66 			     unsigned int *readval)
67 {
68 	struct ad7606_state *st = iio_priv(indio_dev);
69 	int ret;
70 
71 	mutex_lock(&st->lock);
72 	if (readval) {
73 		ret = st->bops->reg_read(st, reg);
74 		if (ret < 0)
75 			goto err_unlock;
76 		*readval = ret;
77 		ret = 0;
78 	} else {
79 		ret = st->bops->reg_write(st, reg, writeval);
80 	}
81 err_unlock:
82 	mutex_unlock(&st->lock);
83 	return ret;
84 }
85 
86 static int ad7606_read_samples(struct ad7606_state *st)
87 {
88 	unsigned int num = st->chip_info->num_channels;
89 	u16 *data = st->data;
90 	int ret;
91 
92 	/*
93 	 * The frstdata signal is set to high while and after reading the sample
94 	 * of the first channel and low for all other channels. This can be used
95 	 * to check that the incoming data is correctly aligned. During normal
96 	 * operation the data should never become unaligned, but some glitch or
97 	 * electrostatic discharge might cause an extra read or clock cycle.
98 	 * Monitoring the frstdata signal allows to recover from such failure
99 	 * situations.
100 	 */
101 
102 	if (st->gpio_frstdata) {
103 		ret = st->bops->read_block(st->dev, 1, data);
104 		if (ret)
105 			return ret;
106 
107 		if (!gpiod_get_value(st->gpio_frstdata)) {
108 			ad7606_reset(st);
109 			return -EIO;
110 		}
111 
112 		data++;
113 		num--;
114 	}
115 
116 	return st->bops->read_block(st->dev, num, data);
117 }
118 
119 static irqreturn_t ad7606_trigger_handler(int irq, void *p)
120 {
121 	struct iio_poll_func *pf = p;
122 	struct iio_dev *indio_dev = pf->indio_dev;
123 	struct ad7606_state *st = iio_priv(indio_dev);
124 	int ret;
125 
126 	mutex_lock(&st->lock);
127 
128 	ret = ad7606_read_samples(st);
129 	if (ret == 0)
130 		iio_push_to_buffers_with_timestamp(indio_dev, st->data,
131 						   iio_get_time_ns(indio_dev));
132 
133 	iio_trigger_notify_done(indio_dev->trig);
134 	/* The rising edge of the CONVST signal starts a new conversion. */
135 	gpiod_set_value(st->gpio_convst, 1);
136 
137 	mutex_unlock(&st->lock);
138 
139 	return IRQ_HANDLED;
140 }
141 
142 static int ad7606_scan_direct(struct iio_dev *indio_dev, unsigned int ch)
143 {
144 	struct ad7606_state *st = iio_priv(indio_dev);
145 	int ret;
146 
147 	gpiod_set_value(st->gpio_convst, 1);
148 	ret = wait_for_completion_timeout(&st->completion,
149 					  msecs_to_jiffies(1000));
150 	if (!ret) {
151 		ret = -ETIMEDOUT;
152 		goto error_ret;
153 	}
154 
155 	ret = ad7606_read_samples(st);
156 	if (ret == 0)
157 		ret = st->data[ch];
158 
159 error_ret:
160 	gpiod_set_value(st->gpio_convst, 0);
161 
162 	return ret;
163 }
164 
165 static int ad7606_read_raw(struct iio_dev *indio_dev,
166 			   struct iio_chan_spec const *chan,
167 			   int *val,
168 			   int *val2,
169 			   long m)
170 {
171 	int ret, ch = 0;
172 	struct ad7606_state *st = iio_priv(indio_dev);
173 
174 	switch (m) {
175 	case IIO_CHAN_INFO_RAW:
176 		ret = iio_device_claim_direct_mode(indio_dev);
177 		if (ret)
178 			return ret;
179 
180 		ret = ad7606_scan_direct(indio_dev, chan->address);
181 		iio_device_release_direct_mode(indio_dev);
182 
183 		if (ret < 0)
184 			return ret;
185 		*val = (short)ret;
186 		return IIO_VAL_INT;
187 	case IIO_CHAN_INFO_SCALE:
188 		if (st->sw_mode_en)
189 			ch = chan->address;
190 		*val = 0;
191 		*val2 = st->scale_avail[st->range[ch]];
192 		return IIO_VAL_INT_PLUS_MICRO;
193 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
194 		*val = st->oversampling;
195 		return IIO_VAL_INT;
196 	}
197 	return -EINVAL;
198 }
199 
200 static ssize_t ad7606_show_avail(char *buf, const unsigned int *vals,
201 				 unsigned int n, bool micros)
202 {
203 	size_t len = 0;
204 	int i;
205 
206 	for (i = 0; i < n; i++) {
207 		len += scnprintf(buf + len, PAGE_SIZE - len,
208 			micros ? "0.%06u " : "%u ", vals[i]);
209 	}
210 	buf[len - 1] = '\n';
211 
212 	return len;
213 }
214 
215 static ssize_t in_voltage_scale_available_show(struct device *dev,
216 					       struct device_attribute *attr,
217 					       char *buf)
218 {
219 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
220 	struct ad7606_state *st = iio_priv(indio_dev);
221 
222 	return ad7606_show_avail(buf, st->scale_avail, st->num_scales, true);
223 }
224 
225 static IIO_DEVICE_ATTR_RO(in_voltage_scale_available, 0);
226 
227 static int ad7606_write_scale_hw(struct iio_dev *indio_dev, int ch, int val)
228 {
229 	struct ad7606_state *st = iio_priv(indio_dev);
230 
231 	gpiod_set_value(st->gpio_range, val);
232 
233 	return 0;
234 }
235 
236 static int ad7606_write_os_hw(struct iio_dev *indio_dev, int val)
237 {
238 	struct ad7606_state *st = iio_priv(indio_dev);
239 	DECLARE_BITMAP(values, 3);
240 
241 	values[0] = val;
242 
243 	gpiod_set_array_value(ARRAY_SIZE(values), st->gpio_os->desc,
244 			      st->gpio_os->info, values);
245 
246 	/* AD7616 requires a reset to update value */
247 	if (st->chip_info->os_req_reset)
248 		ad7606_reset(st);
249 
250 	return 0;
251 }
252 
253 static int ad7606_write_raw(struct iio_dev *indio_dev,
254 			    struct iio_chan_spec const *chan,
255 			    int val,
256 			    int val2,
257 			    long mask)
258 {
259 	struct ad7606_state *st = iio_priv(indio_dev);
260 	int i, ret, ch = 0;
261 
262 	switch (mask) {
263 	case IIO_CHAN_INFO_SCALE:
264 		mutex_lock(&st->lock);
265 		i = find_closest(val2, st->scale_avail, st->num_scales);
266 		if (st->sw_mode_en)
267 			ch = chan->address;
268 		ret = st->write_scale(indio_dev, ch, i);
269 		if (ret < 0) {
270 			mutex_unlock(&st->lock);
271 			return ret;
272 		}
273 		st->range[ch] = i;
274 		mutex_unlock(&st->lock);
275 
276 		return 0;
277 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
278 		if (val2)
279 			return -EINVAL;
280 		i = find_closest(val, st->oversampling_avail,
281 				 st->num_os_ratios);
282 		mutex_lock(&st->lock);
283 		ret = st->write_os(indio_dev, i);
284 		if (ret < 0) {
285 			mutex_unlock(&st->lock);
286 			return ret;
287 		}
288 		st->oversampling = st->oversampling_avail[i];
289 		mutex_unlock(&st->lock);
290 
291 		return 0;
292 	default:
293 		return -EINVAL;
294 	}
295 }
296 
297 static ssize_t ad7606_oversampling_ratio_avail(struct device *dev,
298 					       struct device_attribute *attr,
299 					       char *buf)
300 {
301 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
302 	struct ad7606_state *st = iio_priv(indio_dev);
303 
304 	return ad7606_show_avail(buf, st->oversampling_avail,
305 				 st->num_os_ratios, false);
306 }
307 
308 static IIO_DEVICE_ATTR(oversampling_ratio_available, 0444,
309 		       ad7606_oversampling_ratio_avail, NULL, 0);
310 
311 static struct attribute *ad7606_attributes_os_and_range[] = {
312 	&iio_dev_attr_in_voltage_scale_available.dev_attr.attr,
313 	&iio_dev_attr_oversampling_ratio_available.dev_attr.attr,
314 	NULL,
315 };
316 
317 static const struct attribute_group ad7606_attribute_group_os_and_range = {
318 	.attrs = ad7606_attributes_os_and_range,
319 };
320 
321 static struct attribute *ad7606_attributes_os[] = {
322 	&iio_dev_attr_oversampling_ratio_available.dev_attr.attr,
323 	NULL,
324 };
325 
326 static const struct attribute_group ad7606_attribute_group_os = {
327 	.attrs = ad7606_attributes_os,
328 };
329 
330 static struct attribute *ad7606_attributes_range[] = {
331 	&iio_dev_attr_in_voltage_scale_available.dev_attr.attr,
332 	NULL,
333 };
334 
335 static const struct attribute_group ad7606_attribute_group_range = {
336 	.attrs = ad7606_attributes_range,
337 };
338 
339 static const struct iio_chan_spec ad7605_channels[] = {
340 	IIO_CHAN_SOFT_TIMESTAMP(4),
341 	AD7605_CHANNEL(0),
342 	AD7605_CHANNEL(1),
343 	AD7605_CHANNEL(2),
344 	AD7605_CHANNEL(3),
345 };
346 
347 static const struct iio_chan_spec ad7606_channels[] = {
348 	IIO_CHAN_SOFT_TIMESTAMP(8),
349 	AD7606_CHANNEL(0),
350 	AD7606_CHANNEL(1),
351 	AD7606_CHANNEL(2),
352 	AD7606_CHANNEL(3),
353 	AD7606_CHANNEL(4),
354 	AD7606_CHANNEL(5),
355 	AD7606_CHANNEL(6),
356 	AD7606_CHANNEL(7),
357 };
358 
359 /*
360  * The current assumption that this driver makes for AD7616, is that it's
361  * working in Hardware Mode with Serial, Burst and Sequencer modes activated.
362  * To activate them, following pins must be pulled high:
363  *	-SER/PAR
364  *	-SEQEN
365  * And following pins must be pulled low:
366  *	-WR/BURST
367  *	-DB4/SER1W
368  */
369 static const struct iio_chan_spec ad7616_channels[] = {
370 	IIO_CHAN_SOFT_TIMESTAMP(16),
371 	AD7606_CHANNEL(0),
372 	AD7606_CHANNEL(1),
373 	AD7606_CHANNEL(2),
374 	AD7606_CHANNEL(3),
375 	AD7606_CHANNEL(4),
376 	AD7606_CHANNEL(5),
377 	AD7606_CHANNEL(6),
378 	AD7606_CHANNEL(7),
379 	AD7606_CHANNEL(8),
380 	AD7606_CHANNEL(9),
381 	AD7606_CHANNEL(10),
382 	AD7606_CHANNEL(11),
383 	AD7606_CHANNEL(12),
384 	AD7606_CHANNEL(13),
385 	AD7606_CHANNEL(14),
386 	AD7606_CHANNEL(15),
387 };
388 
389 static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
390 	/* More devices added in future */
391 	[ID_AD7605_4] = {
392 		.channels = ad7605_channels,
393 		.num_channels = 5,
394 	},
395 	[ID_AD7606_8] = {
396 		.channels = ad7606_channels,
397 		.num_channels = 9,
398 		.oversampling_avail = ad7606_oversampling_avail,
399 		.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
400 	},
401 	[ID_AD7606_6] = {
402 		.channels = ad7606_channels,
403 		.num_channels = 7,
404 		.oversampling_avail = ad7606_oversampling_avail,
405 		.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
406 	},
407 	[ID_AD7606_4] = {
408 		.channels = ad7606_channels,
409 		.num_channels = 5,
410 		.oversampling_avail = ad7606_oversampling_avail,
411 		.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
412 	},
413 	[ID_AD7606B] = {
414 		.channels = ad7606_channels,
415 		.num_channels = 9,
416 		.oversampling_avail = ad7606_oversampling_avail,
417 		.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
418 	},
419 	[ID_AD7616] = {
420 		.channels = ad7616_channels,
421 		.num_channels = 17,
422 		.oversampling_avail = ad7616_oversampling_avail,
423 		.oversampling_num = ARRAY_SIZE(ad7616_oversampling_avail),
424 		.os_req_reset = true,
425 		.init_delay_ms = 15,
426 	},
427 };
428 
429 static int ad7606_request_gpios(struct ad7606_state *st)
430 {
431 	struct device *dev = st->dev;
432 
433 	st->gpio_convst = devm_gpiod_get(dev, "adi,conversion-start",
434 					 GPIOD_OUT_LOW);
435 	if (IS_ERR(st->gpio_convst))
436 		return PTR_ERR(st->gpio_convst);
437 
438 	st->gpio_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
439 	if (IS_ERR(st->gpio_reset))
440 		return PTR_ERR(st->gpio_reset);
441 
442 	st->gpio_range = devm_gpiod_get_optional(dev, "adi,range",
443 						 GPIOD_OUT_LOW);
444 	if (IS_ERR(st->gpio_range))
445 		return PTR_ERR(st->gpio_range);
446 
447 	st->gpio_standby = devm_gpiod_get_optional(dev, "standby",
448 						   GPIOD_OUT_HIGH);
449 	if (IS_ERR(st->gpio_standby))
450 		return PTR_ERR(st->gpio_standby);
451 
452 	st->gpio_frstdata = devm_gpiod_get_optional(dev, "adi,first-data",
453 						    GPIOD_IN);
454 	if (IS_ERR(st->gpio_frstdata))
455 		return PTR_ERR(st->gpio_frstdata);
456 
457 	if (!st->chip_info->oversampling_num)
458 		return 0;
459 
460 	st->gpio_os = devm_gpiod_get_array_optional(dev,
461 						    "adi,oversampling-ratio",
462 						    GPIOD_OUT_LOW);
463 	return PTR_ERR_OR_ZERO(st->gpio_os);
464 }
465 
466 /*
467  * The BUSY signal indicates when conversions are in progress, so when a rising
468  * edge of CONVST is applied, BUSY goes logic high and transitions low at the
469  * end of the entire conversion process. The falling edge of the BUSY signal
470  * triggers this interrupt.
471  */
472 static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
473 {
474 	struct iio_dev *indio_dev = dev_id;
475 	struct ad7606_state *st = iio_priv(indio_dev);
476 
477 	if (iio_buffer_enabled(indio_dev)) {
478 		gpiod_set_value(st->gpio_convst, 0);
479 		iio_trigger_poll_chained(st->trig);
480 	} else {
481 		complete(&st->completion);
482 	}
483 
484 	return IRQ_HANDLED;
485 };
486 
487 static int ad7606_validate_trigger(struct iio_dev *indio_dev,
488 				   struct iio_trigger *trig)
489 {
490 	struct ad7606_state *st = iio_priv(indio_dev);
491 
492 	if (st->trig != trig)
493 		return -EINVAL;
494 
495 	return 0;
496 }
497 
498 static int ad7606_buffer_postenable(struct iio_dev *indio_dev)
499 {
500 	struct ad7606_state *st = iio_priv(indio_dev);
501 
502 	iio_triggered_buffer_postenable(indio_dev);
503 	gpiod_set_value(st->gpio_convst, 1);
504 
505 	return 0;
506 }
507 
508 static int ad7606_buffer_predisable(struct iio_dev *indio_dev)
509 {
510 	struct ad7606_state *st = iio_priv(indio_dev);
511 
512 	gpiod_set_value(st->gpio_convst, 0);
513 
514 	return iio_triggered_buffer_predisable(indio_dev);
515 }
516 
517 static const struct iio_buffer_setup_ops ad7606_buffer_ops = {
518 	.postenable = &ad7606_buffer_postenable,
519 	.predisable = &ad7606_buffer_predisable,
520 };
521 
522 static const struct iio_info ad7606_info_no_os_or_range = {
523 	.read_raw = &ad7606_read_raw,
524 	.validate_trigger = &ad7606_validate_trigger,
525 };
526 
527 static const struct iio_info ad7606_info_os_and_range = {
528 	.read_raw = &ad7606_read_raw,
529 	.write_raw = &ad7606_write_raw,
530 	.attrs = &ad7606_attribute_group_os_and_range,
531 	.validate_trigger = &ad7606_validate_trigger,
532 };
533 
534 static const struct iio_info ad7606_info_os_range_and_debug = {
535 	.read_raw = &ad7606_read_raw,
536 	.write_raw = &ad7606_write_raw,
537 	.debugfs_reg_access = &ad7606_reg_access,
538 	.attrs = &ad7606_attribute_group_os_and_range,
539 	.validate_trigger = &ad7606_validate_trigger,
540 };
541 
542 static const struct iio_info ad7606_info_os = {
543 	.read_raw = &ad7606_read_raw,
544 	.write_raw = &ad7606_write_raw,
545 	.attrs = &ad7606_attribute_group_os,
546 	.validate_trigger = &ad7606_validate_trigger,
547 };
548 
549 static const struct iio_info ad7606_info_range = {
550 	.read_raw = &ad7606_read_raw,
551 	.write_raw = &ad7606_write_raw,
552 	.attrs = &ad7606_attribute_group_range,
553 	.validate_trigger = &ad7606_validate_trigger,
554 };
555 
556 static const struct iio_trigger_ops ad7606_trigger_ops = {
557 	.validate_device = iio_trigger_validate_own_device,
558 };
559 
560 static void ad7606_regulator_disable(void *data)
561 {
562 	struct ad7606_state *st = data;
563 
564 	regulator_disable(st->reg);
565 }
566 
567 int ad7606_probe(struct device *dev, int irq, void __iomem *base_address,
568 		 const char *name, unsigned int id,
569 		 const struct ad7606_bus_ops *bops)
570 {
571 	struct ad7606_state *st;
572 	int ret;
573 	struct iio_dev *indio_dev;
574 
575 	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
576 	if (!indio_dev)
577 		return -ENOMEM;
578 
579 	st = iio_priv(indio_dev);
580 	dev_set_drvdata(dev, indio_dev);
581 
582 	st->dev = dev;
583 	mutex_init(&st->lock);
584 	st->bops = bops;
585 	st->base_address = base_address;
586 	/* tied to logic low, analog input range is +/- 5V */
587 	st->range[0] = 0;
588 	st->oversampling = 1;
589 	st->scale_avail = ad7606_scale_avail;
590 	st->num_scales = ARRAY_SIZE(ad7606_scale_avail);
591 
592 	st->reg = devm_regulator_get(dev, "avcc");
593 	if (IS_ERR(st->reg))
594 		return PTR_ERR(st->reg);
595 
596 	ret = regulator_enable(st->reg);
597 	if (ret) {
598 		dev_err(dev, "Failed to enable specified AVcc supply\n");
599 		return ret;
600 	}
601 
602 	ret = devm_add_action_or_reset(dev, ad7606_regulator_disable, st);
603 	if (ret)
604 		return ret;
605 
606 	st->chip_info = &ad7606_chip_info_tbl[id];
607 
608 	if (st->chip_info->oversampling_num) {
609 		st->oversampling_avail = st->chip_info->oversampling_avail;
610 		st->num_os_ratios = st->chip_info->oversampling_num;
611 	}
612 
613 	ret = ad7606_request_gpios(st);
614 	if (ret)
615 		return ret;
616 
617 	indio_dev->dev.parent = dev;
618 	if (st->gpio_os) {
619 		if (st->gpio_range)
620 			indio_dev->info = &ad7606_info_os_and_range;
621 		else
622 			indio_dev->info = &ad7606_info_os;
623 	} else {
624 		if (st->gpio_range)
625 			indio_dev->info = &ad7606_info_range;
626 		else
627 			indio_dev->info = &ad7606_info_no_os_or_range;
628 	}
629 	indio_dev->modes = INDIO_DIRECT_MODE;
630 	indio_dev->name = name;
631 	indio_dev->channels = st->chip_info->channels;
632 	indio_dev->num_channels = st->chip_info->num_channels;
633 
634 	init_completion(&st->completion);
635 
636 	ret = ad7606_reset(st);
637 	if (ret)
638 		dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
639 
640 	/* AD7616 requires al least 15ms to reconfigure after a reset */
641 	if (st->chip_info->init_delay_ms) {
642 		if (msleep_interruptible(st->chip_info->init_delay_ms))
643 			return -ERESTARTSYS;
644 	}
645 
646 	st->write_scale = ad7606_write_scale_hw;
647 	st->write_os = ad7606_write_os_hw;
648 
649 	if (st->bops->sw_mode_config)
650 		st->sw_mode_en = device_property_present(st->dev,
651 							 "adi,sw-mode");
652 
653 	if (st->sw_mode_en) {
654 		/* Scale of 0.076293 is only available in sw mode */
655 		st->scale_avail = ad7616_sw_scale_avail;
656 		st->num_scales = ARRAY_SIZE(ad7616_sw_scale_avail);
657 
658 		/* After reset, in software mode, ±10 V is set by default */
659 		memset32(st->range, 2, ARRAY_SIZE(st->range));
660 		indio_dev->info = &ad7606_info_os_range_and_debug;
661 
662 		ret = st->bops->sw_mode_config(indio_dev);
663 		if (ret < 0)
664 			return ret;
665 	}
666 
667 	st->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
668 					  indio_dev->name, indio_dev->id);
669 	if (!st->trig)
670 		return -ENOMEM;
671 
672 	st->trig->ops = &ad7606_trigger_ops;
673 	st->trig->dev.parent = dev;
674 	iio_trigger_set_drvdata(st->trig, indio_dev);
675 	ret = devm_iio_trigger_register(dev, st->trig);
676 	if (ret)
677 		return ret;
678 
679 	indio_dev->trig = iio_trigger_get(st->trig);
680 
681 	ret = devm_request_threaded_irq(dev, irq,
682 					NULL,
683 					&ad7606_interrupt,
684 					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
685 					name, indio_dev);
686 	if (ret)
687 		return ret;
688 
689 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
690 					      &iio_pollfunc_store_time,
691 					      &ad7606_trigger_handler,
692 					      &ad7606_buffer_ops);
693 	if (ret)
694 		return ret;
695 
696 	return devm_iio_device_register(dev, indio_dev);
697 }
698 EXPORT_SYMBOL_GPL(ad7606_probe);
699 
700 #ifdef CONFIG_PM_SLEEP
701 
702 static int ad7606_suspend(struct device *dev)
703 {
704 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
705 	struct ad7606_state *st = iio_priv(indio_dev);
706 
707 	if (st->gpio_standby) {
708 		gpiod_set_value(st->gpio_range, 1);
709 		gpiod_set_value(st->gpio_standby, 0);
710 	}
711 
712 	return 0;
713 }
714 
715 static int ad7606_resume(struct device *dev)
716 {
717 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
718 	struct ad7606_state *st = iio_priv(indio_dev);
719 
720 	if (st->gpio_standby) {
721 		gpiod_set_value(st->gpio_range, st->range[0]);
722 		gpiod_set_value(st->gpio_standby, 1);
723 		ad7606_reset(st);
724 	}
725 
726 	return 0;
727 }
728 
729 SIMPLE_DEV_PM_OPS(ad7606_pm_ops, ad7606_suspend, ad7606_resume);
730 EXPORT_SYMBOL_GPL(ad7606_pm_ops);
731 
732 #endif
733 
734 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
735 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
736 MODULE_LICENSE("GPL v2");
737