xref: /linux/drivers/iio/adc/ad799x.c (revision 288440de9e5fdb4a3ff73864850f080c1250fc81)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * iio/adc/ad799x.c
4  * Copyright (C) 2010-2011 Michael Hennerich, Analog Devices Inc.
5  *
6  * based on iio/adc/max1363
7  * Copyright (C) 2008-2010 Jonathan Cameron
8  *
9  * based on linux/drivers/i2c/chips/max123x
10  * Copyright (C) 2002-2004 Stefan Eletzhofer
11  *
12  * based on linux/drivers/acron/char/pcf8583.c
13  * Copyright (C) 2000 Russell King
14  *
15  * ad799x.c
16  *
17  * Support for ad7991, ad7995, ad7999, ad7992, ad7993, ad7994, ad7997,
18  * ad7998 and similar chips.
19  */
20 
21 #include <linux/interrupt.h>
22 #include <linux/device.h>
23 #include <linux/kernel.h>
24 #include <linux/sysfs.h>
25 #include <linux/i2c.h>
26 #include <linux/regulator/consumer.h>
27 #include <linux/slab.h>
28 #include <linux/types.h>
29 #include <linux/err.h>
30 #include <linux/module.h>
31 #include <linux/bitops.h>
32 
33 #include <linux/iio/iio.h>
34 #include <linux/iio/sysfs.h>
35 #include <linux/iio/events.h>
36 #include <linux/iio/buffer.h>
37 #include <linux/iio/trigger_consumer.h>
38 #include <linux/iio/triggered_buffer.h>
39 
40 #define AD799X_CHANNEL_SHIFT			4
41 
42 /*
43  * AD7991, AD7995 and AD7999 defines
44  */
45 
46 #define AD7991_REF_SEL				0x08
47 #define AD7991_FLTR				0x04
48 #define AD7991_BIT_TRIAL_DELAY			0x02
49 #define AD7991_SAMPLE_DELAY			0x01
50 
51 /*
52  * AD7992, AD7993, AD7994, AD7997 and AD7998 defines
53  */
54 
55 #define AD7998_FLTR				BIT(3)
56 #define AD7998_ALERT_EN				BIT(2)
57 #define AD7998_BUSY_ALERT			BIT(1)
58 #define AD7998_BUSY_ALERT_POL			BIT(0)
59 
60 #define AD7998_CONV_RES_REG			0x0
61 #define AD7998_ALERT_STAT_REG			0x1
62 #define AD7998_CONF_REG				0x2
63 #define AD7998_CYCLE_TMR_REG			0x3
64 
65 #define AD7998_DATALOW_REG(x)			((x) * 3 + 0x4)
66 #define AD7998_DATAHIGH_REG(x)			((x) * 3 + 0x5)
67 #define AD7998_HYST_REG(x)			((x) * 3 + 0x6)
68 
69 #define AD7998_CYC_MASK				GENMASK(2, 0)
70 #define AD7998_CYC_DIS				0x0
71 #define AD7998_CYC_TCONF_32			0x1
72 #define AD7998_CYC_TCONF_64			0x2
73 #define AD7998_CYC_TCONF_128			0x3
74 #define AD7998_CYC_TCONF_256			0x4
75 #define AD7998_CYC_TCONF_512			0x5
76 #define AD7998_CYC_TCONF_1024			0x6
77 #define AD7998_CYC_TCONF_2048			0x7
78 
79 #define AD7998_ALERT_STAT_CLEAR			0xFF
80 
81 /*
82  * AD7997 and AD7997 defines
83  */
84 
85 #define AD7997_8_READ_SINGLE			BIT(7)
86 #define AD7997_8_READ_SEQUENCE			(BIT(6) | BIT(5) | BIT(4))
87 
88 enum {
89 	ad7991,
90 	ad7995,
91 	ad7999,
92 	ad7992,
93 	ad7993,
94 	ad7994,
95 	ad7997,
96 	ad7998
97 };
98 
99 /**
100  * struct ad799x_chip_config - chip specific information
101  * @channel:		channel specification
102  * @default_config:	device default configuration
103  * @info:		pointer to iio_info struct
104  */
105 struct ad799x_chip_config {
106 	const struct iio_chan_spec	channel[9];
107 	u16				default_config;
108 	const struct iio_info		*info;
109 };
110 
111 /**
112  * struct ad799x_chip_info - chip specific information
113  * @num_channels:	number of channels
114  * @noirq_config:	device configuration w/o IRQ
115  * @irq_config:		device configuration w/IRQ
116  */
117 struct ad799x_chip_info {
118 	int				num_channels;
119 	const struct ad799x_chip_config	noirq_config;
120 	const struct ad799x_chip_config	irq_config;
121 };
122 
123 struct ad799x_state {
124 	struct i2c_client		*client;
125 	const struct ad799x_chip_config	*chip_config;
126 	struct regulator		*reg;
127 	struct regulator		*vref;
128 	unsigned			id;
129 	u16				config;
130 
131 	u8				*rx_buf;
132 	unsigned int			transfer_size;
133 };
134 
135 static int ad799x_write_config(struct ad799x_state *st, u16 val)
136 {
137 	switch (st->id) {
138 	case ad7997:
139 	case ad7998:
140 		return i2c_smbus_write_word_swapped(st->client, AD7998_CONF_REG,
141 			val);
142 	case ad7992:
143 	case ad7993:
144 	case ad7994:
145 		return i2c_smbus_write_byte_data(st->client, AD7998_CONF_REG,
146 			val);
147 	default:
148 		/* Will be written when doing a conversion */
149 		st->config = val;
150 		return 0;
151 	}
152 }
153 
154 static int ad799x_read_config(struct ad799x_state *st)
155 {
156 	switch (st->id) {
157 	case ad7997:
158 	case ad7998:
159 		return i2c_smbus_read_word_swapped(st->client, AD7998_CONF_REG);
160 	case ad7992:
161 	case ad7993:
162 	case ad7994:
163 		return i2c_smbus_read_byte_data(st->client, AD7998_CONF_REG);
164 	default:
165 		/* No readback support */
166 		return st->config;
167 	}
168 }
169 
170 static int ad799x_update_config(struct ad799x_state *st, u16 config)
171 {
172 	int ret;
173 
174 	ret = ad799x_write_config(st, config);
175 	if (ret < 0)
176 		return ret;
177 	ret = ad799x_read_config(st);
178 	if (ret < 0)
179 		return ret;
180 	st->config = ret;
181 
182 	return 0;
183 }
184 
185 static irqreturn_t ad799x_trigger_handler(int irq, void *p)
186 {
187 	struct iio_poll_func *pf = p;
188 	struct iio_dev *indio_dev = pf->indio_dev;
189 	struct ad799x_state *st = iio_priv(indio_dev);
190 	int b_sent;
191 	u8 cmd;
192 
193 	switch (st->id) {
194 	case ad7991:
195 	case ad7995:
196 	case ad7999:
197 		cmd = st->config |
198 			(*indio_dev->active_scan_mask << AD799X_CHANNEL_SHIFT);
199 		break;
200 	case ad7992:
201 	case ad7993:
202 	case ad7994:
203 		cmd = (*indio_dev->active_scan_mask << AD799X_CHANNEL_SHIFT) |
204 			AD7998_CONV_RES_REG;
205 		break;
206 	case ad7997:
207 	case ad7998:
208 		cmd = AD7997_8_READ_SEQUENCE | AD7998_CONV_RES_REG;
209 		break;
210 	default:
211 		cmd = 0;
212 	}
213 
214 	b_sent = i2c_smbus_read_i2c_block_data(st->client,
215 			cmd, st->transfer_size, st->rx_buf);
216 	if (b_sent < 0)
217 		goto out;
218 
219 	iio_push_to_buffers_with_timestamp(indio_dev, st->rx_buf,
220 			iio_get_time_ns(indio_dev));
221 out:
222 	iio_trigger_notify_done(indio_dev->trig);
223 
224 	return IRQ_HANDLED;
225 }
226 
227 static int ad799x_update_scan_mode(struct iio_dev *indio_dev,
228 	const unsigned long *scan_mask)
229 {
230 	struct ad799x_state *st = iio_priv(indio_dev);
231 
232 	kfree(st->rx_buf);
233 	st->rx_buf = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
234 	if (!st->rx_buf)
235 		return -ENOMEM;
236 
237 	st->transfer_size = bitmap_weight(scan_mask, indio_dev->masklength) * 2;
238 
239 	switch (st->id) {
240 	case ad7992:
241 	case ad7993:
242 	case ad7994:
243 	case ad7997:
244 	case ad7998:
245 		st->config &= ~(GENMASK(7, 0) << AD799X_CHANNEL_SHIFT);
246 		st->config |= (*scan_mask << AD799X_CHANNEL_SHIFT);
247 		return ad799x_write_config(st, st->config);
248 	default:
249 		return 0;
250 	}
251 }
252 
253 static int ad799x_scan_direct(struct ad799x_state *st, unsigned ch)
254 {
255 	u8 cmd;
256 
257 	switch (st->id) {
258 	case ad7991:
259 	case ad7995:
260 	case ad7999:
261 		cmd = st->config | (BIT(ch) << AD799X_CHANNEL_SHIFT);
262 		break;
263 	case ad7992:
264 	case ad7993:
265 	case ad7994:
266 		cmd = BIT(ch) << AD799X_CHANNEL_SHIFT;
267 		break;
268 	case ad7997:
269 	case ad7998:
270 		cmd = (ch << AD799X_CHANNEL_SHIFT) | AD7997_8_READ_SINGLE;
271 		break;
272 	default:
273 		return -EINVAL;
274 	}
275 
276 	return i2c_smbus_read_word_swapped(st->client, cmd);
277 }
278 
279 static int ad799x_read_raw(struct iio_dev *indio_dev,
280 			   struct iio_chan_spec const *chan,
281 			   int *val,
282 			   int *val2,
283 			   long m)
284 {
285 	int ret;
286 	struct ad799x_state *st = iio_priv(indio_dev);
287 
288 	switch (m) {
289 	case IIO_CHAN_INFO_RAW:
290 		ret = iio_device_claim_direct_mode(indio_dev);
291 		if (ret)
292 			return ret;
293 		ret = ad799x_scan_direct(st, chan->scan_index);
294 		iio_device_release_direct_mode(indio_dev);
295 
296 		if (ret < 0)
297 			return ret;
298 		*val = (ret >> chan->scan_type.shift) &
299 			GENMASK(chan->scan_type.realbits - 1, 0);
300 		return IIO_VAL_INT;
301 	case IIO_CHAN_INFO_SCALE:
302 		if (st->vref)
303 			ret = regulator_get_voltage(st->vref);
304 		else
305 			ret = regulator_get_voltage(st->reg);
306 
307 		if (ret < 0)
308 			return ret;
309 		*val = ret / 1000;
310 		*val2 = chan->scan_type.realbits;
311 		return IIO_VAL_FRACTIONAL_LOG2;
312 	}
313 	return -EINVAL;
314 }
315 static const unsigned int ad7998_frequencies[] = {
316 	[AD7998_CYC_DIS]	= 0,
317 	[AD7998_CYC_TCONF_32]	= 15625,
318 	[AD7998_CYC_TCONF_64]	= 7812,
319 	[AD7998_CYC_TCONF_128]	= 3906,
320 	[AD7998_CYC_TCONF_512]	= 976,
321 	[AD7998_CYC_TCONF_1024]	= 488,
322 	[AD7998_CYC_TCONF_2048]	= 244,
323 };
324 
325 static ssize_t ad799x_read_frequency(struct device *dev,
326 					struct device_attribute *attr,
327 					char *buf)
328 {
329 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
330 	struct ad799x_state *st = iio_priv(indio_dev);
331 
332 	int ret = i2c_smbus_read_byte_data(st->client, AD7998_CYCLE_TMR_REG);
333 	if (ret < 0)
334 		return ret;
335 
336 	return sprintf(buf, "%u\n", ad7998_frequencies[ret & AD7998_CYC_MASK]);
337 }
338 
339 static ssize_t ad799x_write_frequency(struct device *dev,
340 					 struct device_attribute *attr,
341 					 const char *buf,
342 					 size_t len)
343 {
344 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
345 	struct ad799x_state *st = iio_priv(indio_dev);
346 
347 	long val;
348 	int ret, i;
349 
350 	ret = kstrtol(buf, 10, &val);
351 	if (ret)
352 		return ret;
353 
354 	mutex_lock(&indio_dev->mlock);
355 	ret = i2c_smbus_read_byte_data(st->client, AD7998_CYCLE_TMR_REG);
356 	if (ret < 0)
357 		goto error_ret_mutex;
358 	/* Wipe the bits clean */
359 	ret &= ~AD7998_CYC_MASK;
360 
361 	for (i = 0; i < ARRAY_SIZE(ad7998_frequencies); i++)
362 		if (val == ad7998_frequencies[i])
363 			break;
364 	if (i == ARRAY_SIZE(ad7998_frequencies)) {
365 		ret = -EINVAL;
366 		goto error_ret_mutex;
367 	}
368 
369 	ret = i2c_smbus_write_byte_data(st->client, AD7998_CYCLE_TMR_REG,
370 		ret | i);
371 	if (ret < 0)
372 		goto error_ret_mutex;
373 	ret = len;
374 
375 error_ret_mutex:
376 	mutex_unlock(&indio_dev->mlock);
377 
378 	return ret;
379 }
380 
381 static int ad799x_read_event_config(struct iio_dev *indio_dev,
382 				    const struct iio_chan_spec *chan,
383 				    enum iio_event_type type,
384 				    enum iio_event_direction dir)
385 {
386 	struct ad799x_state *st = iio_priv(indio_dev);
387 
388 	if (!(st->config & AD7998_ALERT_EN))
389 		return 0;
390 
391 	if ((st->config >> AD799X_CHANNEL_SHIFT) & BIT(chan->scan_index))
392 		return 1;
393 
394 	return 0;
395 }
396 
397 static int ad799x_write_event_config(struct iio_dev *indio_dev,
398 				     const struct iio_chan_spec *chan,
399 				     enum iio_event_type type,
400 				     enum iio_event_direction dir,
401 				     int state)
402 {
403 	struct ad799x_state *st = iio_priv(indio_dev);
404 	int ret;
405 
406 	ret = iio_device_claim_direct_mode(indio_dev);
407 	if (ret)
408 		return ret;
409 
410 	if (state)
411 		st->config |= BIT(chan->scan_index) << AD799X_CHANNEL_SHIFT;
412 	else
413 		st->config &= ~(BIT(chan->scan_index) << AD799X_CHANNEL_SHIFT);
414 
415 	if (st->config >> AD799X_CHANNEL_SHIFT)
416 		st->config |= AD7998_ALERT_EN;
417 	else
418 		st->config &= ~AD7998_ALERT_EN;
419 
420 	ret = ad799x_write_config(st, st->config);
421 	iio_device_release_direct_mode(indio_dev);
422 	return ret;
423 }
424 
425 static unsigned int ad799x_threshold_reg(const struct iio_chan_spec *chan,
426 					 enum iio_event_direction dir,
427 					 enum iio_event_info info)
428 {
429 	switch (info) {
430 	case IIO_EV_INFO_VALUE:
431 		if (dir == IIO_EV_DIR_FALLING)
432 			return AD7998_DATALOW_REG(chan->channel);
433 		else
434 			return AD7998_DATAHIGH_REG(chan->channel);
435 	case IIO_EV_INFO_HYSTERESIS:
436 		return AD7998_HYST_REG(chan->channel);
437 	default:
438 		return -EINVAL;
439 	}
440 
441 	return 0;
442 }
443 
444 static int ad799x_write_event_value(struct iio_dev *indio_dev,
445 				    const struct iio_chan_spec *chan,
446 				    enum iio_event_type type,
447 				    enum iio_event_direction dir,
448 				    enum iio_event_info info,
449 				    int val, int val2)
450 {
451 	int ret;
452 	struct ad799x_state *st = iio_priv(indio_dev);
453 
454 	if (val < 0 || val > GENMASK(chan->scan_type.realbits - 1, 0))
455 		return -EINVAL;
456 
457 	mutex_lock(&indio_dev->mlock);
458 	ret = i2c_smbus_write_word_swapped(st->client,
459 		ad799x_threshold_reg(chan, dir, info),
460 		val << chan->scan_type.shift);
461 	mutex_unlock(&indio_dev->mlock);
462 
463 	return ret;
464 }
465 
466 static int ad799x_read_event_value(struct iio_dev *indio_dev,
467 				    const struct iio_chan_spec *chan,
468 				    enum iio_event_type type,
469 				    enum iio_event_direction dir,
470 				    enum iio_event_info info,
471 				    int *val, int *val2)
472 {
473 	int ret;
474 	struct ad799x_state *st = iio_priv(indio_dev);
475 
476 	mutex_lock(&indio_dev->mlock);
477 	ret = i2c_smbus_read_word_swapped(st->client,
478 		ad799x_threshold_reg(chan, dir, info));
479 	mutex_unlock(&indio_dev->mlock);
480 	if (ret < 0)
481 		return ret;
482 	*val = (ret >> chan->scan_type.shift) &
483 		GENMASK(chan->scan_type.realbits - 1, 0);
484 
485 	return IIO_VAL_INT;
486 }
487 
488 static irqreturn_t ad799x_event_handler(int irq, void *private)
489 {
490 	struct iio_dev *indio_dev = private;
491 	struct ad799x_state *st = iio_priv(private);
492 	int i, ret;
493 
494 	ret = i2c_smbus_read_byte_data(st->client, AD7998_ALERT_STAT_REG);
495 	if (ret <= 0)
496 		goto done;
497 
498 	if (i2c_smbus_write_byte_data(st->client, AD7998_ALERT_STAT_REG,
499 		AD7998_ALERT_STAT_CLEAR) < 0)
500 		goto done;
501 
502 	for (i = 0; i < 8; i++) {
503 		if (ret & BIT(i))
504 			iio_push_event(indio_dev,
505 				       i & 0x1 ?
506 				       IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
507 							    (i >> 1),
508 							    IIO_EV_TYPE_THRESH,
509 							    IIO_EV_DIR_RISING) :
510 				       IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
511 							    (i >> 1),
512 							    IIO_EV_TYPE_THRESH,
513 							    IIO_EV_DIR_FALLING),
514 				       iio_get_time_ns(indio_dev));
515 	}
516 
517 done:
518 	return IRQ_HANDLED;
519 }
520 
521 static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
522 			      ad799x_read_frequency,
523 			      ad799x_write_frequency);
524 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("15625 7812 3906 1953 976 488 244 0");
525 
526 static struct attribute *ad799x_event_attributes[] = {
527 	&iio_dev_attr_sampling_frequency.dev_attr.attr,
528 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
529 	NULL,
530 };
531 
532 static const struct attribute_group ad799x_event_attrs_group = {
533 	.attrs = ad799x_event_attributes,
534 };
535 
536 static const struct iio_info ad7991_info = {
537 	.read_raw = &ad799x_read_raw,
538 	.update_scan_mode = ad799x_update_scan_mode,
539 };
540 
541 static const struct iio_info ad7993_4_7_8_noirq_info = {
542 	.read_raw = &ad799x_read_raw,
543 	.update_scan_mode = ad799x_update_scan_mode,
544 };
545 
546 static const struct iio_info ad7993_4_7_8_irq_info = {
547 	.read_raw = &ad799x_read_raw,
548 	.event_attrs = &ad799x_event_attrs_group,
549 	.read_event_config = &ad799x_read_event_config,
550 	.write_event_config = &ad799x_write_event_config,
551 	.read_event_value = &ad799x_read_event_value,
552 	.write_event_value = &ad799x_write_event_value,
553 	.update_scan_mode = ad799x_update_scan_mode,
554 };
555 
556 static const struct iio_event_spec ad799x_events[] = {
557 	{
558 		.type = IIO_EV_TYPE_THRESH,
559 		.dir = IIO_EV_DIR_RISING,
560 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
561 			BIT(IIO_EV_INFO_ENABLE),
562 	}, {
563 		.type = IIO_EV_TYPE_THRESH,
564 		.dir = IIO_EV_DIR_FALLING,
565 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
566 			BIT(IIO_EV_INFO_ENABLE),
567 	}, {
568 		.type = IIO_EV_TYPE_THRESH,
569 		.dir = IIO_EV_DIR_EITHER,
570 		.mask_separate = BIT(IIO_EV_INFO_HYSTERESIS),
571 	},
572 };
573 
574 #define _AD799X_CHANNEL(_index, _realbits, _ev_spec, _num_ev_spec) { \
575 	.type = IIO_VOLTAGE, \
576 	.indexed = 1, \
577 	.channel = (_index), \
578 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
579 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
580 	.scan_index = (_index), \
581 	.scan_type = { \
582 		.sign = 'u', \
583 		.realbits = (_realbits), \
584 		.storagebits = 16, \
585 		.shift = 12 - (_realbits), \
586 		.endianness = IIO_BE, \
587 	}, \
588 	.event_spec = _ev_spec, \
589 	.num_event_specs = _num_ev_spec, \
590 }
591 
592 #define AD799X_CHANNEL(_index, _realbits) \
593 	_AD799X_CHANNEL(_index, _realbits, NULL, 0)
594 
595 #define AD799X_CHANNEL_WITH_EVENTS(_index, _realbits) \
596 	_AD799X_CHANNEL(_index, _realbits, ad799x_events, \
597 		ARRAY_SIZE(ad799x_events))
598 
599 static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
600 	[ad7991] = {
601 		.num_channels = 5,
602 		.noirq_config = {
603 			.channel = {
604 				AD799X_CHANNEL(0, 12),
605 				AD799X_CHANNEL(1, 12),
606 				AD799X_CHANNEL(2, 12),
607 				AD799X_CHANNEL(3, 12),
608 				IIO_CHAN_SOFT_TIMESTAMP(4),
609 			},
610 			.info = &ad7991_info,
611 		},
612 	},
613 	[ad7995] = {
614 		.num_channels = 5,
615 		.noirq_config = {
616 			.channel = {
617 				AD799X_CHANNEL(0, 10),
618 				AD799X_CHANNEL(1, 10),
619 				AD799X_CHANNEL(2, 10),
620 				AD799X_CHANNEL(3, 10),
621 				IIO_CHAN_SOFT_TIMESTAMP(4),
622 			},
623 			.info = &ad7991_info,
624 		},
625 	},
626 	[ad7999] = {
627 		.num_channels = 5,
628 		.noirq_config = {
629 			.channel = {
630 				AD799X_CHANNEL(0, 8),
631 				AD799X_CHANNEL(1, 8),
632 				AD799X_CHANNEL(2, 8),
633 				AD799X_CHANNEL(3, 8),
634 				IIO_CHAN_SOFT_TIMESTAMP(4),
635 			},
636 			.info = &ad7991_info,
637 		},
638 	},
639 	[ad7992] = {
640 		.num_channels = 3,
641 		.noirq_config = {
642 			.channel = {
643 				AD799X_CHANNEL(0, 12),
644 				AD799X_CHANNEL(1, 12),
645 				IIO_CHAN_SOFT_TIMESTAMP(3),
646 			},
647 			.info = &ad7993_4_7_8_noirq_info,
648 		},
649 		.irq_config = {
650 			.channel = {
651 				AD799X_CHANNEL_WITH_EVENTS(0, 12),
652 				AD799X_CHANNEL_WITH_EVENTS(1, 12),
653 				IIO_CHAN_SOFT_TIMESTAMP(3),
654 			},
655 			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
656 			.info = &ad7993_4_7_8_irq_info,
657 		},
658 	},
659 	[ad7993] = {
660 		.num_channels = 5,
661 		.noirq_config = {
662 			.channel = {
663 				AD799X_CHANNEL(0, 10),
664 				AD799X_CHANNEL(1, 10),
665 				AD799X_CHANNEL(2, 10),
666 				AD799X_CHANNEL(3, 10),
667 				IIO_CHAN_SOFT_TIMESTAMP(4),
668 			},
669 			.info = &ad7993_4_7_8_noirq_info,
670 		},
671 		.irq_config = {
672 			.channel = {
673 				AD799X_CHANNEL_WITH_EVENTS(0, 10),
674 				AD799X_CHANNEL_WITH_EVENTS(1, 10),
675 				AD799X_CHANNEL_WITH_EVENTS(2, 10),
676 				AD799X_CHANNEL_WITH_EVENTS(3, 10),
677 				IIO_CHAN_SOFT_TIMESTAMP(4),
678 			},
679 			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
680 			.info = &ad7993_4_7_8_irq_info,
681 		},
682 	},
683 	[ad7994] = {
684 		.num_channels = 5,
685 		.noirq_config = {
686 			.channel = {
687 				AD799X_CHANNEL(0, 12),
688 				AD799X_CHANNEL(1, 12),
689 				AD799X_CHANNEL(2, 12),
690 				AD799X_CHANNEL(3, 12),
691 				IIO_CHAN_SOFT_TIMESTAMP(4),
692 			},
693 			.info = &ad7993_4_7_8_noirq_info,
694 		},
695 		.irq_config = {
696 			.channel = {
697 				AD799X_CHANNEL_WITH_EVENTS(0, 12),
698 				AD799X_CHANNEL_WITH_EVENTS(1, 12),
699 				AD799X_CHANNEL_WITH_EVENTS(2, 12),
700 				AD799X_CHANNEL_WITH_EVENTS(3, 12),
701 				IIO_CHAN_SOFT_TIMESTAMP(4),
702 			},
703 			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
704 			.info = &ad7993_4_7_8_irq_info,
705 		},
706 	},
707 	[ad7997] = {
708 		.num_channels = 9,
709 		.noirq_config = {
710 			.channel = {
711 				AD799X_CHANNEL(0, 10),
712 				AD799X_CHANNEL(1, 10),
713 				AD799X_CHANNEL(2, 10),
714 				AD799X_CHANNEL(3, 10),
715 				AD799X_CHANNEL(4, 10),
716 				AD799X_CHANNEL(5, 10),
717 				AD799X_CHANNEL(6, 10),
718 				AD799X_CHANNEL(7, 10),
719 				IIO_CHAN_SOFT_TIMESTAMP(8),
720 			},
721 			.info = &ad7993_4_7_8_noirq_info,
722 		},
723 		.irq_config = {
724 			.channel = {
725 				AD799X_CHANNEL_WITH_EVENTS(0, 10),
726 				AD799X_CHANNEL_WITH_EVENTS(1, 10),
727 				AD799X_CHANNEL_WITH_EVENTS(2, 10),
728 				AD799X_CHANNEL_WITH_EVENTS(3, 10),
729 				AD799X_CHANNEL(4, 10),
730 				AD799X_CHANNEL(5, 10),
731 				AD799X_CHANNEL(6, 10),
732 				AD799X_CHANNEL(7, 10),
733 				IIO_CHAN_SOFT_TIMESTAMP(8),
734 			},
735 			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
736 			.info = &ad7993_4_7_8_irq_info,
737 		},
738 	},
739 	[ad7998] = {
740 		.num_channels = 9,
741 		.noirq_config = {
742 			.channel = {
743 				AD799X_CHANNEL(0, 12),
744 				AD799X_CHANNEL(1, 12),
745 				AD799X_CHANNEL(2, 12),
746 				AD799X_CHANNEL(3, 12),
747 				AD799X_CHANNEL(4, 12),
748 				AD799X_CHANNEL(5, 12),
749 				AD799X_CHANNEL(6, 12),
750 				AD799X_CHANNEL(7, 12),
751 				IIO_CHAN_SOFT_TIMESTAMP(8),
752 			},
753 			.info = &ad7993_4_7_8_noirq_info,
754 		},
755 		.irq_config = {
756 			.channel = {
757 				AD799X_CHANNEL_WITH_EVENTS(0, 12),
758 				AD799X_CHANNEL_WITH_EVENTS(1, 12),
759 				AD799X_CHANNEL_WITH_EVENTS(2, 12),
760 				AD799X_CHANNEL_WITH_EVENTS(3, 12),
761 				AD799X_CHANNEL(4, 12),
762 				AD799X_CHANNEL(5, 12),
763 				AD799X_CHANNEL(6, 12),
764 				AD799X_CHANNEL(7, 12),
765 				IIO_CHAN_SOFT_TIMESTAMP(8),
766 			},
767 			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
768 			.info = &ad7993_4_7_8_irq_info,
769 		},
770 	},
771 };
772 
773 static int ad799x_probe(struct i2c_client *client,
774 				   const struct i2c_device_id *id)
775 {
776 	int ret;
777 	int extra_config = 0;
778 	struct ad799x_state *st;
779 	struct iio_dev *indio_dev;
780 	const struct ad799x_chip_info *chip_info =
781 		&ad799x_chip_info_tbl[id->driver_data];
782 
783 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
784 	if (indio_dev == NULL)
785 		return -ENOMEM;
786 
787 	st = iio_priv(indio_dev);
788 	/* this is only used for device removal purposes */
789 	i2c_set_clientdata(client, indio_dev);
790 
791 	st->id = id->driver_data;
792 	if (client->irq > 0 && chip_info->irq_config.info)
793 		st->chip_config = &chip_info->irq_config;
794 	else
795 		st->chip_config = &chip_info->noirq_config;
796 
797 	/* TODO: Add pdata options for filtering and bit delay */
798 
799 	st->reg = devm_regulator_get(&client->dev, "vcc");
800 	if (IS_ERR(st->reg))
801 		return PTR_ERR(st->reg);
802 	ret = regulator_enable(st->reg);
803 	if (ret)
804 		return ret;
805 
806 	/* check if an external reference is supplied */
807 	st->vref = devm_regulator_get_optional(&client->dev, "vref");
808 
809 	if (IS_ERR(st->vref)) {
810 		if (PTR_ERR(st->vref) == -ENODEV) {
811 			st->vref = NULL;
812 			dev_info(&client->dev, "Using VCC reference voltage\n");
813 		} else {
814 			ret = PTR_ERR(st->vref);
815 			goto error_disable_reg;
816 		}
817 	}
818 
819 	if (st->vref) {
820 		/*
821 		 * Use external reference voltage if supported by hardware.
822 		 * This is optional if voltage / regulator present, use VCC otherwise.
823 		 */
824 		if ((st->id == ad7991) || (st->id == ad7995) || (st->id == ad7999)) {
825 			dev_info(&client->dev, "Using external reference voltage\n");
826 			extra_config |= AD7991_REF_SEL;
827 			ret = regulator_enable(st->vref);
828 			if (ret)
829 				goto error_disable_reg;
830 		} else {
831 			st->vref = NULL;
832 			dev_warn(&client->dev, "Supplied reference not supported\n");
833 		}
834 	}
835 
836 	st->client = client;
837 
838 	indio_dev->name = id->name;
839 	indio_dev->info = st->chip_config->info;
840 
841 	indio_dev->modes = INDIO_DIRECT_MODE;
842 	indio_dev->channels = st->chip_config->channel;
843 	indio_dev->num_channels = chip_info->num_channels;
844 
845 	ret = ad799x_update_config(st, st->chip_config->default_config | extra_config);
846 	if (ret)
847 		goto error_disable_vref;
848 
849 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
850 		&ad799x_trigger_handler, NULL);
851 	if (ret)
852 		goto error_disable_vref;
853 
854 	if (client->irq > 0) {
855 		ret = devm_request_threaded_irq(&client->dev,
856 						client->irq,
857 						NULL,
858 						ad799x_event_handler,
859 						IRQF_TRIGGER_FALLING |
860 						IRQF_ONESHOT,
861 						client->name,
862 						indio_dev);
863 		if (ret)
864 			goto error_cleanup_ring;
865 	}
866 	ret = iio_device_register(indio_dev);
867 	if (ret)
868 		goto error_cleanup_ring;
869 
870 	return 0;
871 
872 error_cleanup_ring:
873 	iio_triggered_buffer_cleanup(indio_dev);
874 error_disable_vref:
875 	if (st->vref)
876 		regulator_disable(st->vref);
877 error_disable_reg:
878 	regulator_disable(st->reg);
879 
880 	return ret;
881 }
882 
883 static int ad799x_remove(struct i2c_client *client)
884 {
885 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
886 	struct ad799x_state *st = iio_priv(indio_dev);
887 
888 	iio_device_unregister(indio_dev);
889 
890 	iio_triggered_buffer_cleanup(indio_dev);
891 	if (st->vref)
892 		regulator_disable(st->vref);
893 	regulator_disable(st->reg);
894 	kfree(st->rx_buf);
895 
896 	return 0;
897 }
898 
899 static int ad799x_suspend(struct device *dev)
900 {
901 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
902 	struct ad799x_state *st = iio_priv(indio_dev);
903 
904 	if (st->vref)
905 		regulator_disable(st->vref);
906 	regulator_disable(st->reg);
907 
908 	return 0;
909 }
910 
911 static int ad799x_resume(struct device *dev)
912 {
913 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
914 	struct ad799x_state *st = iio_priv(indio_dev);
915 	int ret;
916 
917 	ret = regulator_enable(st->reg);
918 	if (ret) {
919 		dev_err(dev, "Unable to enable vcc regulator\n");
920 		return ret;
921 	}
922 
923 	if (st->vref) {
924 		ret = regulator_enable(st->vref);
925 		if (ret) {
926 			regulator_disable(st->reg);
927 			dev_err(dev, "Unable to enable vref regulator\n");
928 			return ret;
929 		}
930 	}
931 
932 	/* resync config */
933 	ret = ad799x_update_config(st, st->config);
934 	if (ret) {
935 		if (st->vref)
936 			regulator_disable(st->vref);
937 		regulator_disable(st->reg);
938 		return ret;
939 	}
940 
941 	return 0;
942 }
943 
944 static DEFINE_SIMPLE_DEV_PM_OPS(ad799x_pm_ops, ad799x_suspend, ad799x_resume);
945 
946 static const struct i2c_device_id ad799x_id[] = {
947 	{ "ad7991", ad7991 },
948 	{ "ad7995", ad7995 },
949 	{ "ad7999", ad7999 },
950 	{ "ad7992", ad7992 },
951 	{ "ad7993", ad7993 },
952 	{ "ad7994", ad7994 },
953 	{ "ad7997", ad7997 },
954 	{ "ad7998", ad7998 },
955 	{}
956 };
957 
958 MODULE_DEVICE_TABLE(i2c, ad799x_id);
959 
960 static struct i2c_driver ad799x_driver = {
961 	.driver = {
962 		.name = "ad799x",
963 		.pm = pm_sleep_ptr(&ad799x_pm_ops),
964 	},
965 	.probe = ad799x_probe,
966 	.remove = ad799x_remove,
967 	.id_table = ad799x_id,
968 };
969 module_i2c_driver(ad799x_driver);
970 
971 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
972 MODULE_DESCRIPTION("Analog Devices AD799x ADC");
973 MODULE_LICENSE("GPL v2");
974