xref: /openbmc/linux/drivers/iio/adc/ad799x.c (revision e3d786a3)
1 /*
2  * iio/adc/ad799x.c
3  * Copyright (C) 2010-2011 Michael Hennerich, Analog Devices Inc.
4  *
5  * based on iio/adc/max1363
6  * Copyright (C) 2008-2010 Jonathan Cameron
7  *
8  * based on linux/drivers/i2c/chips/max123x
9  * Copyright (C) 2002-2004 Stefan Eletzhofer
10  *
11  * based on linux/drivers/acron/char/pcf8583.c
12  * Copyright (C) 2000 Russell King
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License version 2 as
16  * published by the Free Software Foundation.
17  *
18  * ad799x.c
19  *
20  * Support for ad7991, ad7995, ad7999, ad7992, ad7993, ad7994, ad7997,
21  * ad7998 and similar chips.
22  *
23  */
24 
25 #include <linux/interrupt.h>
26 #include <linux/device.h>
27 #include <linux/kernel.h>
28 #include <linux/sysfs.h>
29 #include <linux/i2c.h>
30 #include <linux/regulator/consumer.h>
31 #include <linux/slab.h>
32 #include <linux/types.h>
33 #include <linux/err.h>
34 #include <linux/module.h>
35 #include <linux/bitops.h>
36 
37 #include <linux/iio/iio.h>
38 #include <linux/iio/sysfs.h>
39 #include <linux/iio/events.h>
40 #include <linux/iio/buffer.h>
41 #include <linux/iio/trigger_consumer.h>
42 #include <linux/iio/triggered_buffer.h>
43 
44 #define AD799X_CHANNEL_SHIFT			4
45 
46 /*
47  * AD7991, AD7995 and AD7999 defines
48  */
49 
50 #define AD7991_REF_SEL				0x08
51 #define AD7991_FLTR				0x04
52 #define AD7991_BIT_TRIAL_DELAY			0x02
53 #define AD7991_SAMPLE_DELAY			0x01
54 
55 /*
56  * AD7992, AD7993, AD7994, AD7997 and AD7998 defines
57  */
58 
59 #define AD7998_FLTR				BIT(3)
60 #define AD7998_ALERT_EN				BIT(2)
61 #define AD7998_BUSY_ALERT			BIT(1)
62 #define AD7998_BUSY_ALERT_POL			BIT(0)
63 
64 #define AD7998_CONV_RES_REG			0x0
65 #define AD7998_ALERT_STAT_REG			0x1
66 #define AD7998_CONF_REG				0x2
67 #define AD7998_CYCLE_TMR_REG			0x3
68 
69 #define AD7998_DATALOW_REG(x)			((x) * 3 + 0x4)
70 #define AD7998_DATAHIGH_REG(x)			((x) * 3 + 0x5)
71 #define AD7998_HYST_REG(x)			((x) * 3 + 0x6)
72 
73 #define AD7998_CYC_MASK				GENMASK(2, 0)
74 #define AD7998_CYC_DIS				0x0
75 #define AD7998_CYC_TCONF_32			0x1
76 #define AD7998_CYC_TCONF_64			0x2
77 #define AD7998_CYC_TCONF_128			0x3
78 #define AD7998_CYC_TCONF_256			0x4
79 #define AD7998_CYC_TCONF_512			0x5
80 #define AD7998_CYC_TCONF_1024			0x6
81 #define AD7998_CYC_TCONF_2048			0x7
82 
83 #define AD7998_ALERT_STAT_CLEAR			0xFF
84 
85 /*
86  * AD7997 and AD7997 defines
87  */
88 
89 #define AD7997_8_READ_SINGLE			BIT(7)
90 #define AD7997_8_READ_SEQUENCE			(BIT(6) | BIT(5) | BIT(4))
91 
92 enum {
93 	ad7991,
94 	ad7995,
95 	ad7999,
96 	ad7992,
97 	ad7993,
98 	ad7994,
99 	ad7997,
100 	ad7998
101 };
102 
103 /**
104  * struct ad799x_chip_config - chip specific information
105  * @channel:		channel specification
106  * @default_config:	device default configuration
107  * @info:		pointer to iio_info struct
108  */
109 struct ad799x_chip_config {
110 	const struct iio_chan_spec	channel[9];
111 	u16				default_config;
112 	const struct iio_info		*info;
113 };
114 
115 /**
116  * struct ad799x_chip_info - chip specific information
117  * @num_channels:	number of channels
118  * @noirq_config:	device configuration w/o IRQ
119  * @irq_config:		device configuration w/IRQ
120  */
121 struct ad799x_chip_info {
122 	int				num_channels;
123 	const struct ad799x_chip_config	noirq_config;
124 	const struct ad799x_chip_config	irq_config;
125 };
126 
127 struct ad799x_state {
128 	struct i2c_client		*client;
129 	const struct ad799x_chip_config	*chip_config;
130 	struct regulator		*reg;
131 	struct regulator		*vref;
132 	unsigned			id;
133 	u16				config;
134 
135 	u8				*rx_buf;
136 	unsigned int			transfer_size;
137 };
138 
139 static int ad799x_write_config(struct ad799x_state *st, u16 val)
140 {
141 	switch (st->id) {
142 	case ad7997:
143 	case ad7998:
144 		return i2c_smbus_write_word_swapped(st->client, AD7998_CONF_REG,
145 			val);
146 	case ad7992:
147 	case ad7993:
148 	case ad7994:
149 		return i2c_smbus_write_byte_data(st->client, AD7998_CONF_REG,
150 			val);
151 	default:
152 		/* Will be written when doing a conversion */
153 		st->config = val;
154 		return 0;
155 	}
156 }
157 
158 static int ad799x_read_config(struct ad799x_state *st)
159 {
160 	switch (st->id) {
161 	case ad7997:
162 	case ad7998:
163 		return i2c_smbus_read_word_swapped(st->client, AD7998_CONF_REG);
164 	case ad7992:
165 	case ad7993:
166 	case ad7994:
167 		return i2c_smbus_read_byte_data(st->client, AD7998_CONF_REG);
168 	default:
169 		/* No readback support */
170 		return st->config;
171 	}
172 }
173 
174 /**
175  * ad799x_trigger_handler() bh of trigger launched polling to ring buffer
176  *
177  * Currently there is no option in this driver to disable the saving of
178  * timestamps within the ring.
179  **/
180 static irqreturn_t ad799x_trigger_handler(int irq, void *p)
181 {
182 	struct iio_poll_func *pf = p;
183 	struct iio_dev *indio_dev = pf->indio_dev;
184 	struct ad799x_state *st = iio_priv(indio_dev);
185 	int b_sent;
186 	u8 cmd;
187 
188 	switch (st->id) {
189 	case ad7991:
190 	case ad7995:
191 	case ad7999:
192 		cmd = st->config |
193 			(*indio_dev->active_scan_mask << AD799X_CHANNEL_SHIFT);
194 		break;
195 	case ad7992:
196 	case ad7993:
197 	case ad7994:
198 		cmd = (*indio_dev->active_scan_mask << AD799X_CHANNEL_SHIFT) |
199 			AD7998_CONV_RES_REG;
200 		break;
201 	case ad7997:
202 	case ad7998:
203 		cmd = AD7997_8_READ_SEQUENCE | AD7998_CONV_RES_REG;
204 		break;
205 	default:
206 		cmd = 0;
207 	}
208 
209 	b_sent = i2c_smbus_read_i2c_block_data(st->client,
210 			cmd, st->transfer_size, st->rx_buf);
211 	if (b_sent < 0)
212 		goto out;
213 
214 	iio_push_to_buffers_with_timestamp(indio_dev, st->rx_buf,
215 			iio_get_time_ns(indio_dev));
216 out:
217 	iio_trigger_notify_done(indio_dev->trig);
218 
219 	return IRQ_HANDLED;
220 }
221 
222 static int ad799x_update_scan_mode(struct iio_dev *indio_dev,
223 	const unsigned long *scan_mask)
224 {
225 	struct ad799x_state *st = iio_priv(indio_dev);
226 
227 	kfree(st->rx_buf);
228 	st->rx_buf = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
229 	if (!st->rx_buf)
230 		return -ENOMEM;
231 
232 	st->transfer_size = bitmap_weight(scan_mask, indio_dev->masklength) * 2;
233 
234 	switch (st->id) {
235 	case ad7992:
236 	case ad7993:
237 	case ad7994:
238 	case ad7997:
239 	case ad7998:
240 		st->config &= ~(GENMASK(7, 0) << AD799X_CHANNEL_SHIFT);
241 		st->config |= (*scan_mask << AD799X_CHANNEL_SHIFT);
242 		return ad799x_write_config(st, st->config);
243 	default:
244 		return 0;
245 	}
246 }
247 
248 static int ad799x_scan_direct(struct ad799x_state *st, unsigned ch)
249 {
250 	u8 cmd;
251 
252 	switch (st->id) {
253 	case ad7991:
254 	case ad7995:
255 	case ad7999:
256 		cmd = st->config | (BIT(ch) << AD799X_CHANNEL_SHIFT);
257 		break;
258 	case ad7992:
259 	case ad7993:
260 	case ad7994:
261 		cmd = BIT(ch) << AD799X_CHANNEL_SHIFT;
262 		break;
263 	case ad7997:
264 	case ad7998:
265 		cmd = (ch << AD799X_CHANNEL_SHIFT) | AD7997_8_READ_SINGLE;
266 		break;
267 	default:
268 		return -EINVAL;
269 	}
270 
271 	return i2c_smbus_read_word_swapped(st->client, cmd);
272 }
273 
274 static int ad799x_read_raw(struct iio_dev *indio_dev,
275 			   struct iio_chan_spec const *chan,
276 			   int *val,
277 			   int *val2,
278 			   long m)
279 {
280 	int ret;
281 	struct ad799x_state *st = iio_priv(indio_dev);
282 
283 	switch (m) {
284 	case IIO_CHAN_INFO_RAW:
285 		ret = iio_device_claim_direct_mode(indio_dev);
286 		if (ret)
287 			return ret;
288 		ret = ad799x_scan_direct(st, chan->scan_index);
289 		iio_device_release_direct_mode(indio_dev);
290 
291 		if (ret < 0)
292 			return ret;
293 		*val = (ret >> chan->scan_type.shift) &
294 			GENMASK(chan->scan_type.realbits - 1, 0);
295 		return IIO_VAL_INT;
296 	case IIO_CHAN_INFO_SCALE:
297 		ret = regulator_get_voltage(st->vref);
298 		if (ret < 0)
299 			return ret;
300 		*val = ret / 1000;
301 		*val2 = chan->scan_type.realbits;
302 		return IIO_VAL_FRACTIONAL_LOG2;
303 	}
304 	return -EINVAL;
305 }
306 static const unsigned int ad7998_frequencies[] = {
307 	[AD7998_CYC_DIS]	= 0,
308 	[AD7998_CYC_TCONF_32]	= 15625,
309 	[AD7998_CYC_TCONF_64]	= 7812,
310 	[AD7998_CYC_TCONF_128]	= 3906,
311 	[AD7998_CYC_TCONF_512]	= 976,
312 	[AD7998_CYC_TCONF_1024]	= 488,
313 	[AD7998_CYC_TCONF_2048]	= 244,
314 };
315 
316 static ssize_t ad799x_read_frequency(struct device *dev,
317 					struct device_attribute *attr,
318 					char *buf)
319 {
320 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
321 	struct ad799x_state *st = iio_priv(indio_dev);
322 
323 	int ret = i2c_smbus_read_byte_data(st->client, AD7998_CYCLE_TMR_REG);
324 	if (ret < 0)
325 		return ret;
326 
327 	return sprintf(buf, "%u\n", ad7998_frequencies[ret & AD7998_CYC_MASK]);
328 }
329 
330 static ssize_t ad799x_write_frequency(struct device *dev,
331 					 struct device_attribute *attr,
332 					 const char *buf,
333 					 size_t len)
334 {
335 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
336 	struct ad799x_state *st = iio_priv(indio_dev);
337 
338 	long val;
339 	int ret, i;
340 
341 	ret = kstrtol(buf, 10, &val);
342 	if (ret)
343 		return ret;
344 
345 	mutex_lock(&indio_dev->mlock);
346 	ret = i2c_smbus_read_byte_data(st->client, AD7998_CYCLE_TMR_REG);
347 	if (ret < 0)
348 		goto error_ret_mutex;
349 	/* Wipe the bits clean */
350 	ret &= ~AD7998_CYC_MASK;
351 
352 	for (i = 0; i < ARRAY_SIZE(ad7998_frequencies); i++)
353 		if (val == ad7998_frequencies[i])
354 			break;
355 	if (i == ARRAY_SIZE(ad7998_frequencies)) {
356 		ret = -EINVAL;
357 		goto error_ret_mutex;
358 	}
359 
360 	ret = i2c_smbus_write_byte_data(st->client, AD7998_CYCLE_TMR_REG,
361 		ret | i);
362 	if (ret < 0)
363 		goto error_ret_mutex;
364 	ret = len;
365 
366 error_ret_mutex:
367 	mutex_unlock(&indio_dev->mlock);
368 
369 	return ret;
370 }
371 
372 static int ad799x_read_event_config(struct iio_dev *indio_dev,
373 				    const struct iio_chan_spec *chan,
374 				    enum iio_event_type type,
375 				    enum iio_event_direction dir)
376 {
377 	struct ad799x_state *st = iio_priv(indio_dev);
378 
379 	if (!(st->config & AD7998_ALERT_EN))
380 		return 0;
381 
382 	if ((st->config >> AD799X_CHANNEL_SHIFT) & BIT(chan->scan_index))
383 		return 1;
384 
385 	return 0;
386 }
387 
388 static int ad799x_write_event_config(struct iio_dev *indio_dev,
389 				     const struct iio_chan_spec *chan,
390 				     enum iio_event_type type,
391 				     enum iio_event_direction dir,
392 				     int state)
393 {
394 	struct ad799x_state *st = iio_priv(indio_dev);
395 	int ret;
396 
397 	ret = iio_device_claim_direct_mode(indio_dev);
398 	if (ret)
399 		return ret;
400 
401 	if (state)
402 		st->config |= BIT(chan->scan_index) << AD799X_CHANNEL_SHIFT;
403 	else
404 		st->config &= ~(BIT(chan->scan_index) << AD799X_CHANNEL_SHIFT);
405 
406 	if (st->config >> AD799X_CHANNEL_SHIFT)
407 		st->config |= AD7998_ALERT_EN;
408 	else
409 		st->config &= ~AD7998_ALERT_EN;
410 
411 	ret = ad799x_write_config(st, st->config);
412 	iio_device_release_direct_mode(indio_dev);
413 	return ret;
414 }
415 
416 static unsigned int ad799x_threshold_reg(const struct iio_chan_spec *chan,
417 					 enum iio_event_direction dir,
418 					 enum iio_event_info info)
419 {
420 	switch (info) {
421 	case IIO_EV_INFO_VALUE:
422 		if (dir == IIO_EV_DIR_FALLING)
423 			return AD7998_DATALOW_REG(chan->channel);
424 		else
425 			return AD7998_DATAHIGH_REG(chan->channel);
426 	case IIO_EV_INFO_HYSTERESIS:
427 		return AD7998_HYST_REG(chan->channel);
428 	default:
429 		return -EINVAL;
430 	}
431 
432 	return 0;
433 }
434 
435 static int ad799x_write_event_value(struct iio_dev *indio_dev,
436 				    const struct iio_chan_spec *chan,
437 				    enum iio_event_type type,
438 				    enum iio_event_direction dir,
439 				    enum iio_event_info info,
440 				    int val, int val2)
441 {
442 	int ret;
443 	struct ad799x_state *st = iio_priv(indio_dev);
444 
445 	if (val < 0 || val > GENMASK(chan->scan_type.realbits - 1, 0))
446 		return -EINVAL;
447 
448 	mutex_lock(&indio_dev->mlock);
449 	ret = i2c_smbus_write_word_swapped(st->client,
450 		ad799x_threshold_reg(chan, dir, info),
451 		val << chan->scan_type.shift);
452 	mutex_unlock(&indio_dev->mlock);
453 
454 	return ret;
455 }
456 
457 static int ad799x_read_event_value(struct iio_dev *indio_dev,
458 				    const struct iio_chan_spec *chan,
459 				    enum iio_event_type type,
460 				    enum iio_event_direction dir,
461 				    enum iio_event_info info,
462 				    int *val, int *val2)
463 {
464 	int ret;
465 	struct ad799x_state *st = iio_priv(indio_dev);
466 
467 	mutex_lock(&indio_dev->mlock);
468 	ret = i2c_smbus_read_word_swapped(st->client,
469 		ad799x_threshold_reg(chan, dir, info));
470 	mutex_unlock(&indio_dev->mlock);
471 	if (ret < 0)
472 		return ret;
473 	*val = (ret >> chan->scan_type.shift) &
474 		GENMASK(chan->scan_type.realbits - 1, 0);
475 
476 	return IIO_VAL_INT;
477 }
478 
479 static irqreturn_t ad799x_event_handler(int irq, void *private)
480 {
481 	struct iio_dev *indio_dev = private;
482 	struct ad799x_state *st = iio_priv(private);
483 	int i, ret;
484 
485 	ret = i2c_smbus_read_byte_data(st->client, AD7998_ALERT_STAT_REG);
486 	if (ret <= 0)
487 		goto done;
488 
489 	if (i2c_smbus_write_byte_data(st->client, AD7998_ALERT_STAT_REG,
490 		AD7998_ALERT_STAT_CLEAR) < 0)
491 		goto done;
492 
493 	for (i = 0; i < 8; i++) {
494 		if (ret & BIT(i))
495 			iio_push_event(indio_dev,
496 				       i & 0x1 ?
497 				       IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
498 							    (i >> 1),
499 							    IIO_EV_TYPE_THRESH,
500 							    IIO_EV_DIR_RISING) :
501 				       IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
502 							    (i >> 1),
503 							    IIO_EV_TYPE_THRESH,
504 							    IIO_EV_DIR_FALLING),
505 				       iio_get_time_ns(indio_dev));
506 	}
507 
508 done:
509 	return IRQ_HANDLED;
510 }
511 
512 static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
513 			      ad799x_read_frequency,
514 			      ad799x_write_frequency);
515 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("15625 7812 3906 1953 976 488 244 0");
516 
517 static struct attribute *ad799x_event_attributes[] = {
518 	&iio_dev_attr_sampling_frequency.dev_attr.attr,
519 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
520 	NULL,
521 };
522 
523 static const struct attribute_group ad799x_event_attrs_group = {
524 	.attrs = ad799x_event_attributes,
525 };
526 
527 static const struct iio_info ad7991_info = {
528 	.read_raw = &ad799x_read_raw,
529 	.update_scan_mode = ad799x_update_scan_mode,
530 };
531 
532 static const struct iio_info ad7993_4_7_8_noirq_info = {
533 	.read_raw = &ad799x_read_raw,
534 	.update_scan_mode = ad799x_update_scan_mode,
535 };
536 
537 static const struct iio_info ad7993_4_7_8_irq_info = {
538 	.read_raw = &ad799x_read_raw,
539 	.event_attrs = &ad799x_event_attrs_group,
540 	.read_event_config = &ad799x_read_event_config,
541 	.write_event_config = &ad799x_write_event_config,
542 	.read_event_value = &ad799x_read_event_value,
543 	.write_event_value = &ad799x_write_event_value,
544 	.update_scan_mode = ad799x_update_scan_mode,
545 };
546 
547 static const struct iio_event_spec ad799x_events[] = {
548 	{
549 		.type = IIO_EV_TYPE_THRESH,
550 		.dir = IIO_EV_DIR_RISING,
551 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
552 			BIT(IIO_EV_INFO_ENABLE),
553 	}, {
554 		.type = IIO_EV_TYPE_THRESH,
555 		.dir = IIO_EV_DIR_FALLING,
556 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
557 			BIT(IIO_EV_INFO_ENABLE),
558 	}, {
559 		.type = IIO_EV_TYPE_THRESH,
560 		.dir = IIO_EV_DIR_EITHER,
561 		.mask_separate = BIT(IIO_EV_INFO_HYSTERESIS),
562 	},
563 };
564 
565 #define _AD799X_CHANNEL(_index, _realbits, _ev_spec, _num_ev_spec) { \
566 	.type = IIO_VOLTAGE, \
567 	.indexed = 1, \
568 	.channel = (_index), \
569 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
570 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
571 	.scan_index = (_index), \
572 	.scan_type = { \
573 		.sign = 'u', \
574 		.realbits = (_realbits), \
575 		.storagebits = 16, \
576 		.shift = 12 - (_realbits), \
577 		.endianness = IIO_BE, \
578 	}, \
579 	.event_spec = _ev_spec, \
580 	.num_event_specs = _num_ev_spec, \
581 }
582 
583 #define AD799X_CHANNEL(_index, _realbits) \
584 	_AD799X_CHANNEL(_index, _realbits, NULL, 0)
585 
586 #define AD799X_CHANNEL_WITH_EVENTS(_index, _realbits) \
587 	_AD799X_CHANNEL(_index, _realbits, ad799x_events, \
588 		ARRAY_SIZE(ad799x_events))
589 
590 static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
591 	[ad7991] = {
592 		.num_channels = 5,
593 		.noirq_config = {
594 			.channel = {
595 				AD799X_CHANNEL(0, 12),
596 				AD799X_CHANNEL(1, 12),
597 				AD799X_CHANNEL(2, 12),
598 				AD799X_CHANNEL(3, 12),
599 				IIO_CHAN_SOFT_TIMESTAMP(4),
600 			},
601 			.info = &ad7991_info,
602 		},
603 	},
604 	[ad7995] = {
605 		.num_channels = 5,
606 		.noirq_config = {
607 			.channel = {
608 				AD799X_CHANNEL(0, 10),
609 				AD799X_CHANNEL(1, 10),
610 				AD799X_CHANNEL(2, 10),
611 				AD799X_CHANNEL(3, 10),
612 				IIO_CHAN_SOFT_TIMESTAMP(4),
613 			},
614 			.info = &ad7991_info,
615 		},
616 	},
617 	[ad7999] = {
618 		.num_channels = 5,
619 		.noirq_config = {
620 			.channel = {
621 				AD799X_CHANNEL(0, 8),
622 				AD799X_CHANNEL(1, 8),
623 				AD799X_CHANNEL(2, 8),
624 				AD799X_CHANNEL(3, 8),
625 				IIO_CHAN_SOFT_TIMESTAMP(4),
626 			},
627 			.info = &ad7991_info,
628 		},
629 	},
630 	[ad7992] = {
631 		.num_channels = 3,
632 		.noirq_config = {
633 			.channel = {
634 				AD799X_CHANNEL(0, 12),
635 				AD799X_CHANNEL(1, 12),
636 				IIO_CHAN_SOFT_TIMESTAMP(3),
637 			},
638 			.info = &ad7993_4_7_8_noirq_info,
639 		},
640 		.irq_config = {
641 			.channel = {
642 				AD799X_CHANNEL_WITH_EVENTS(0, 12),
643 				AD799X_CHANNEL_WITH_EVENTS(1, 12),
644 				IIO_CHAN_SOFT_TIMESTAMP(3),
645 			},
646 			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
647 			.info = &ad7993_4_7_8_irq_info,
648 		},
649 	},
650 	[ad7993] = {
651 		.num_channels = 5,
652 		.noirq_config = {
653 			.channel = {
654 				AD799X_CHANNEL(0, 10),
655 				AD799X_CHANNEL(1, 10),
656 				AD799X_CHANNEL(2, 10),
657 				AD799X_CHANNEL(3, 10),
658 				IIO_CHAN_SOFT_TIMESTAMP(4),
659 			},
660 			.info = &ad7993_4_7_8_noirq_info,
661 		},
662 		.irq_config = {
663 			.channel = {
664 				AD799X_CHANNEL_WITH_EVENTS(0, 10),
665 				AD799X_CHANNEL_WITH_EVENTS(1, 10),
666 				AD799X_CHANNEL_WITH_EVENTS(2, 10),
667 				AD799X_CHANNEL_WITH_EVENTS(3, 10),
668 				IIO_CHAN_SOFT_TIMESTAMP(4),
669 			},
670 			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
671 			.info = &ad7993_4_7_8_irq_info,
672 		},
673 	},
674 	[ad7994] = {
675 		.num_channels = 5,
676 		.noirq_config = {
677 			.channel = {
678 				AD799X_CHANNEL(0, 12),
679 				AD799X_CHANNEL(1, 12),
680 				AD799X_CHANNEL(2, 12),
681 				AD799X_CHANNEL(3, 12),
682 				IIO_CHAN_SOFT_TIMESTAMP(4),
683 			},
684 			.info = &ad7993_4_7_8_noirq_info,
685 		},
686 		.irq_config = {
687 			.channel = {
688 				AD799X_CHANNEL_WITH_EVENTS(0, 12),
689 				AD799X_CHANNEL_WITH_EVENTS(1, 12),
690 				AD799X_CHANNEL_WITH_EVENTS(2, 12),
691 				AD799X_CHANNEL_WITH_EVENTS(3, 12),
692 				IIO_CHAN_SOFT_TIMESTAMP(4),
693 			},
694 			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
695 			.info = &ad7993_4_7_8_irq_info,
696 		},
697 	},
698 	[ad7997] = {
699 		.num_channels = 9,
700 		.noirq_config = {
701 			.channel = {
702 				AD799X_CHANNEL(0, 10),
703 				AD799X_CHANNEL(1, 10),
704 				AD799X_CHANNEL(2, 10),
705 				AD799X_CHANNEL(3, 10),
706 				AD799X_CHANNEL(4, 10),
707 				AD799X_CHANNEL(5, 10),
708 				AD799X_CHANNEL(6, 10),
709 				AD799X_CHANNEL(7, 10),
710 				IIO_CHAN_SOFT_TIMESTAMP(8),
711 			},
712 			.info = &ad7993_4_7_8_noirq_info,
713 		},
714 		.irq_config = {
715 			.channel = {
716 				AD799X_CHANNEL_WITH_EVENTS(0, 10),
717 				AD799X_CHANNEL_WITH_EVENTS(1, 10),
718 				AD799X_CHANNEL_WITH_EVENTS(2, 10),
719 				AD799X_CHANNEL_WITH_EVENTS(3, 10),
720 				AD799X_CHANNEL(4, 10),
721 				AD799X_CHANNEL(5, 10),
722 				AD799X_CHANNEL(6, 10),
723 				AD799X_CHANNEL(7, 10),
724 				IIO_CHAN_SOFT_TIMESTAMP(8),
725 			},
726 			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
727 			.info = &ad7993_4_7_8_irq_info,
728 		},
729 	},
730 	[ad7998] = {
731 		.num_channels = 9,
732 		.noirq_config = {
733 			.channel = {
734 				AD799X_CHANNEL(0, 12),
735 				AD799X_CHANNEL(1, 12),
736 				AD799X_CHANNEL(2, 12),
737 				AD799X_CHANNEL(3, 12),
738 				AD799X_CHANNEL(4, 12),
739 				AD799X_CHANNEL(5, 12),
740 				AD799X_CHANNEL(6, 12),
741 				AD799X_CHANNEL(7, 12),
742 				IIO_CHAN_SOFT_TIMESTAMP(8),
743 			},
744 			.info = &ad7993_4_7_8_noirq_info,
745 		},
746 		.irq_config = {
747 			.channel = {
748 				AD799X_CHANNEL_WITH_EVENTS(0, 12),
749 				AD799X_CHANNEL_WITH_EVENTS(1, 12),
750 				AD799X_CHANNEL_WITH_EVENTS(2, 12),
751 				AD799X_CHANNEL_WITH_EVENTS(3, 12),
752 				AD799X_CHANNEL(4, 12),
753 				AD799X_CHANNEL(5, 12),
754 				AD799X_CHANNEL(6, 12),
755 				AD799X_CHANNEL(7, 12),
756 				IIO_CHAN_SOFT_TIMESTAMP(8),
757 			},
758 			.default_config = AD7998_ALERT_EN | AD7998_BUSY_ALERT,
759 			.info = &ad7993_4_7_8_irq_info,
760 		},
761 	},
762 };
763 
764 static int ad799x_probe(struct i2c_client *client,
765 				   const struct i2c_device_id *id)
766 {
767 	int ret;
768 	struct ad799x_state *st;
769 	struct iio_dev *indio_dev;
770 	const struct ad799x_chip_info *chip_info =
771 		&ad799x_chip_info_tbl[id->driver_data];
772 
773 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
774 	if (indio_dev == NULL)
775 		return -ENOMEM;
776 
777 	st = iio_priv(indio_dev);
778 	/* this is only used for device removal purposes */
779 	i2c_set_clientdata(client, indio_dev);
780 
781 	st->id = id->driver_data;
782 	if (client->irq > 0 && chip_info->irq_config.info)
783 		st->chip_config = &chip_info->irq_config;
784 	else
785 		st->chip_config = &chip_info->noirq_config;
786 
787 	/* TODO: Add pdata options for filtering and bit delay */
788 
789 	st->reg = devm_regulator_get(&client->dev, "vcc");
790 	if (IS_ERR(st->reg))
791 		return PTR_ERR(st->reg);
792 	ret = regulator_enable(st->reg);
793 	if (ret)
794 		return ret;
795 	st->vref = devm_regulator_get(&client->dev, "vref");
796 	if (IS_ERR(st->vref)) {
797 		ret = PTR_ERR(st->vref);
798 		goto error_disable_reg;
799 	}
800 	ret = regulator_enable(st->vref);
801 	if (ret)
802 		goto error_disable_reg;
803 
804 	st->client = client;
805 
806 	indio_dev->dev.parent = &client->dev;
807 	indio_dev->dev.of_node = client->dev.of_node;
808 	indio_dev->name = id->name;
809 	indio_dev->info = st->chip_config->info;
810 
811 	indio_dev->modes = INDIO_DIRECT_MODE;
812 	indio_dev->channels = st->chip_config->channel;
813 	indio_dev->num_channels = chip_info->num_channels;
814 
815 	ret = ad799x_write_config(st, st->chip_config->default_config);
816 	if (ret < 0)
817 		goto error_disable_reg;
818 	ret = ad799x_read_config(st);
819 	if (ret < 0)
820 		goto error_disable_reg;
821 	st->config = ret;
822 
823 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
824 		&ad799x_trigger_handler, NULL);
825 	if (ret)
826 		goto error_disable_vref;
827 
828 	if (client->irq > 0) {
829 		ret = devm_request_threaded_irq(&client->dev,
830 						client->irq,
831 						NULL,
832 						ad799x_event_handler,
833 						IRQF_TRIGGER_FALLING |
834 						IRQF_ONESHOT,
835 						client->name,
836 						indio_dev);
837 		if (ret)
838 			goto error_cleanup_ring;
839 	}
840 	ret = iio_device_register(indio_dev);
841 	if (ret)
842 		goto error_cleanup_ring;
843 
844 	return 0;
845 
846 error_cleanup_ring:
847 	iio_triggered_buffer_cleanup(indio_dev);
848 error_disable_vref:
849 	regulator_disable(st->vref);
850 error_disable_reg:
851 	regulator_disable(st->reg);
852 
853 	return ret;
854 }
855 
856 static int ad799x_remove(struct i2c_client *client)
857 {
858 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
859 	struct ad799x_state *st = iio_priv(indio_dev);
860 
861 	iio_device_unregister(indio_dev);
862 
863 	iio_triggered_buffer_cleanup(indio_dev);
864 	regulator_disable(st->vref);
865 	regulator_disable(st->reg);
866 	kfree(st->rx_buf);
867 
868 	return 0;
869 }
870 
871 static const struct i2c_device_id ad799x_id[] = {
872 	{ "ad7991", ad7991 },
873 	{ "ad7995", ad7995 },
874 	{ "ad7999", ad7999 },
875 	{ "ad7992", ad7992 },
876 	{ "ad7993", ad7993 },
877 	{ "ad7994", ad7994 },
878 	{ "ad7997", ad7997 },
879 	{ "ad7998", ad7998 },
880 	{}
881 };
882 
883 MODULE_DEVICE_TABLE(i2c, ad799x_id);
884 
885 static struct i2c_driver ad799x_driver = {
886 	.driver = {
887 		.name = "ad799x",
888 	},
889 	.probe = ad799x_probe,
890 	.remove = ad799x_remove,
891 	.id_table = ad799x_id,
892 };
893 module_i2c_driver(ad799x_driver);
894 
895 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
896 MODULE_DESCRIPTION("Analog Devices AD799x ADC");
897 MODULE_LICENSE("GPL v2");
898