xref: /openbmc/linux/drivers/iio/adc/ad799x.c (revision d2999e1b)
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 
36 #include <linux/iio/iio.h>
37 #include <linux/iio/sysfs.h>
38 #include <linux/iio/events.h>
39 #include <linux/iio/buffer.h>
40 #include <linux/iio/trigger_consumer.h>
41 #include <linux/iio/triggered_buffer.h>
42 
43 #define AD799X_CHANNEL_SHIFT			4
44 #define AD799X_STORAGEBITS			16
45 /*
46  * AD7991, AD7995 and AD7999 defines
47  */
48 
49 #define AD7991_REF_SEL				0x08
50 #define AD7991_FLTR				0x04
51 #define AD7991_BIT_TRIAL_DELAY			0x02
52 #define AD7991_SAMPLE_DELAY			0x01
53 
54 /*
55  * AD7992, AD7993, AD7994, AD7997 and AD7998 defines
56  */
57 
58 #define AD7998_FLTR				0x08
59 #define AD7998_ALERT_EN				0x04
60 #define AD7998_BUSY_ALERT			0x02
61 #define AD7998_BUSY_ALERT_POL			0x01
62 
63 #define AD7998_CONV_RES_REG			0x0
64 #define AD7998_ALERT_STAT_REG			0x1
65 #define AD7998_CONF_REG				0x2
66 #define AD7998_CYCLE_TMR_REG			0x3
67 
68 #define AD7998_DATALOW_REG(x)			((x) * 3 + 0x4)
69 #define AD7998_DATAHIGH_REG(x)			((x) * 3 + 0x5)
70 #define AD7998_HYST_REG(x)			((x) * 3 + 0x6)
71 
72 #define AD7998_CYC_MASK				0x7
73 #define AD7998_CYC_DIS				0x0
74 #define AD7998_CYC_TCONF_32			0x1
75 #define AD7998_CYC_TCONF_64			0x2
76 #define AD7998_CYC_TCONF_128			0x3
77 #define AD7998_CYC_TCONF_256			0x4
78 #define AD7998_CYC_TCONF_512			0x5
79 #define AD7998_CYC_TCONF_1024			0x6
80 #define AD7998_CYC_TCONF_2048			0x7
81 
82 #define AD7998_ALERT_STAT_CLEAR			0xFF
83 
84 /*
85  * AD7997 and AD7997 defines
86  */
87 
88 #define AD7997_8_READ_SINGLE			0x80
89 #define AD7997_8_READ_SEQUENCE			0x70
90 /* TODO: move this into a common header */
91 #define RES_MASK(bits)	((1 << (bits)) - 1)
92 
93 enum {
94 	ad7991,
95 	ad7995,
96 	ad7999,
97 	ad7992,
98 	ad7993,
99 	ad7994,
100 	ad7997,
101 	ad7998
102 };
103 
104 /**
105  * struct ad799x_chip_info - chip specific information
106  * @channel:		channel specification
107  * @num_channels:	number of channels
108  * @monitor_mode:	whether the chip supports monitor interrupts
109  * @default_config:	device default configuration
110  * @event_attrs:	pointer to the monitor event attribute group
111  */
112 struct ad799x_chip_info {
113 	struct iio_chan_spec		channel[9];
114 	int				num_channels;
115 	u16				default_config;
116 	const struct iio_info		*info;
117 };
118 
119 struct ad799x_state {
120 	struct i2c_client		*client;
121 	const struct ad799x_chip_info	*chip_info;
122 	struct regulator		*reg;
123 	struct regulator		*vref;
124 	unsigned			id;
125 	u16				config;
126 
127 	u8				*rx_buf;
128 	unsigned int			transfer_size;
129 };
130 
131 /**
132  * ad799x_trigger_handler() bh of trigger launched polling to ring buffer
133  *
134  * Currently there is no option in this driver to disable the saving of
135  * timestamps within the ring.
136  **/
137 static irqreturn_t ad799x_trigger_handler(int irq, void *p)
138 {
139 	struct iio_poll_func *pf = p;
140 	struct iio_dev *indio_dev = pf->indio_dev;
141 	struct ad799x_state *st = iio_priv(indio_dev);
142 	int b_sent;
143 	u8 cmd;
144 
145 	switch (st->id) {
146 	case ad7991:
147 	case ad7995:
148 	case ad7999:
149 		cmd = st->config |
150 			(*indio_dev->active_scan_mask << AD799X_CHANNEL_SHIFT);
151 		break;
152 	case ad7992:
153 	case ad7993:
154 	case ad7994:
155 		cmd = (*indio_dev->active_scan_mask << AD799X_CHANNEL_SHIFT) |
156 			AD7998_CONV_RES_REG;
157 		break;
158 	case ad7997:
159 	case ad7998:
160 		cmd = AD7997_8_READ_SEQUENCE | AD7998_CONV_RES_REG;
161 		break;
162 	default:
163 		cmd = 0;
164 	}
165 
166 	b_sent = i2c_smbus_read_i2c_block_data(st->client,
167 			cmd, st->transfer_size, st->rx_buf);
168 	if (b_sent < 0)
169 		goto out;
170 
171 	iio_push_to_buffers_with_timestamp(indio_dev, st->rx_buf,
172 			iio_get_time_ns());
173 out:
174 	iio_trigger_notify_done(indio_dev->trig);
175 
176 	return IRQ_HANDLED;
177 }
178 
179 /*
180  * ad799x register access by I2C
181  */
182 static int ad799x_i2c_read16(struct ad799x_state *st, u8 reg, u16 *data)
183 {
184 	struct i2c_client *client = st->client;
185 	int ret = 0;
186 
187 	ret = i2c_smbus_read_word_swapped(client, reg);
188 	if (ret < 0) {
189 		dev_err(&client->dev, "I2C read error\n");
190 		return ret;
191 	}
192 
193 	*data = (u16)ret;
194 
195 	return 0;
196 }
197 
198 static int ad799x_i2c_read8(struct ad799x_state *st, u8 reg, u8 *data)
199 {
200 	struct i2c_client *client = st->client;
201 	int ret = 0;
202 
203 	ret = i2c_smbus_read_byte_data(client, reg);
204 	if (ret < 0) {
205 		dev_err(&client->dev, "I2C read error\n");
206 		return ret;
207 	}
208 
209 	*data = (u8)ret;
210 
211 	return 0;
212 }
213 
214 static int ad799x_i2c_write16(struct ad799x_state *st, u8 reg, u16 data)
215 {
216 	struct i2c_client *client = st->client;
217 	int ret = 0;
218 
219 	ret = i2c_smbus_write_word_swapped(client, reg, data);
220 	if (ret < 0)
221 		dev_err(&client->dev, "I2C write error\n");
222 
223 	return ret;
224 }
225 
226 static int ad799x_i2c_write8(struct ad799x_state *st, u8 reg, u8 data)
227 {
228 	struct i2c_client *client = st->client;
229 	int ret = 0;
230 
231 	ret = i2c_smbus_write_byte_data(client, reg, data);
232 	if (ret < 0)
233 		dev_err(&client->dev, "I2C write error\n");
234 
235 	return ret;
236 }
237 
238 static int ad7997_8_update_scan_mode(struct iio_dev *indio_dev,
239 	const unsigned long *scan_mask)
240 {
241 	struct ad799x_state *st = iio_priv(indio_dev);
242 
243 	kfree(st->rx_buf);
244 	st->rx_buf = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
245 	if (!st->rx_buf)
246 		return -ENOMEM;
247 
248 	st->transfer_size = bitmap_weight(scan_mask, indio_dev->masklength) * 2;
249 
250 	switch (st->id) {
251 	case ad7997:
252 	case ad7998:
253 		return ad799x_i2c_write16(st, AD7998_CONF_REG,
254 			st->config | (*scan_mask << AD799X_CHANNEL_SHIFT));
255 	default:
256 		break;
257 	}
258 
259 	return 0;
260 }
261 
262 static int ad799x_scan_direct(struct ad799x_state *st, unsigned ch)
263 {
264 	u16 rxbuf;
265 	u8 cmd;
266 	int ret;
267 
268 	switch (st->id) {
269 	case ad7991:
270 	case ad7995:
271 	case ad7999:
272 		cmd = st->config | ((1 << ch) << AD799X_CHANNEL_SHIFT);
273 		break;
274 	case ad7992:
275 	case ad7993:
276 	case ad7994:
277 		cmd = (1 << ch) << AD799X_CHANNEL_SHIFT;
278 		break;
279 	case ad7997:
280 	case ad7998:
281 		cmd = (ch << AD799X_CHANNEL_SHIFT) | AD7997_8_READ_SINGLE;
282 		break;
283 	default:
284 		return -EINVAL;
285 	}
286 
287 	ret = ad799x_i2c_read16(st, cmd, &rxbuf);
288 	if (ret < 0)
289 		return ret;
290 
291 	return rxbuf;
292 }
293 
294 static int ad799x_read_raw(struct iio_dev *indio_dev,
295 			   struct iio_chan_spec const *chan,
296 			   int *val,
297 			   int *val2,
298 			   long m)
299 {
300 	int ret;
301 	struct ad799x_state *st = iio_priv(indio_dev);
302 
303 	switch (m) {
304 	case IIO_CHAN_INFO_RAW:
305 		mutex_lock(&indio_dev->mlock);
306 		if (iio_buffer_enabled(indio_dev))
307 			ret = -EBUSY;
308 		else
309 			ret = ad799x_scan_direct(st, chan->scan_index);
310 		mutex_unlock(&indio_dev->mlock);
311 
312 		if (ret < 0)
313 			return ret;
314 		*val = (ret >> chan->scan_type.shift) &
315 			RES_MASK(chan->scan_type.realbits);
316 		return IIO_VAL_INT;
317 	case IIO_CHAN_INFO_SCALE:
318 		ret = regulator_get_voltage(st->vref);
319 		if (ret < 0)
320 			return ret;
321 		*val = ret / 1000;
322 		*val2 = chan->scan_type.realbits;
323 		return IIO_VAL_FRACTIONAL_LOG2;
324 	}
325 	return -EINVAL;
326 }
327 static const unsigned int ad7998_frequencies[] = {
328 	[AD7998_CYC_DIS]	= 0,
329 	[AD7998_CYC_TCONF_32]	= 15625,
330 	[AD7998_CYC_TCONF_64]	= 7812,
331 	[AD7998_CYC_TCONF_128]	= 3906,
332 	[AD7998_CYC_TCONF_512]	= 976,
333 	[AD7998_CYC_TCONF_1024]	= 488,
334 	[AD7998_CYC_TCONF_2048]	= 244,
335 };
336 static ssize_t ad799x_read_frequency(struct device *dev,
337 					struct device_attribute *attr,
338 					char *buf)
339 {
340 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
341 	struct ad799x_state *st = iio_priv(indio_dev);
342 
343 	int ret;
344 	u8 val;
345 	ret = ad799x_i2c_read8(st, AD7998_CYCLE_TMR_REG, &val);
346 	if (ret)
347 		return ret;
348 
349 	val &= AD7998_CYC_MASK;
350 
351 	return sprintf(buf, "%u\n", ad7998_frequencies[val]);
352 }
353 
354 static ssize_t ad799x_write_frequency(struct device *dev,
355 					 struct device_attribute *attr,
356 					 const char *buf,
357 					 size_t len)
358 {
359 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
360 	struct ad799x_state *st = iio_priv(indio_dev);
361 
362 	long val;
363 	int ret, i;
364 	u8 t;
365 
366 	ret = kstrtol(buf, 10, &val);
367 	if (ret)
368 		return ret;
369 
370 	mutex_lock(&indio_dev->mlock);
371 	ret = ad799x_i2c_read8(st, AD7998_CYCLE_TMR_REG, &t);
372 	if (ret)
373 		goto error_ret_mutex;
374 	/* Wipe the bits clean */
375 	t &= ~AD7998_CYC_MASK;
376 
377 	for (i = 0; i < ARRAY_SIZE(ad7998_frequencies); i++)
378 		if (val == ad7998_frequencies[i])
379 			break;
380 	if (i == ARRAY_SIZE(ad7998_frequencies)) {
381 		ret = -EINVAL;
382 		goto error_ret_mutex;
383 	}
384 	t |= i;
385 	ret = ad799x_i2c_write8(st, AD7998_CYCLE_TMR_REG, t);
386 
387 error_ret_mutex:
388 	mutex_unlock(&indio_dev->mlock);
389 
390 	return ret ? ret : len;
391 }
392 
393 static int ad799x_read_event_config(struct iio_dev *indio_dev,
394 				    const struct iio_chan_spec *chan,
395 				    enum iio_event_type type,
396 				    enum iio_event_direction dir)
397 {
398 	return 1;
399 }
400 
401 static unsigned int ad799x_threshold_reg(const struct iio_chan_spec *chan,
402 					 enum iio_event_direction dir,
403 					 enum iio_event_info info)
404 {
405 	switch (info) {
406 	case IIO_EV_INFO_VALUE:
407 		if (dir == IIO_EV_DIR_FALLING)
408 			return AD7998_DATALOW_REG(chan->channel);
409 		else
410 			return AD7998_DATAHIGH_REG(chan->channel);
411 	case IIO_EV_INFO_HYSTERESIS:
412 		return AD7998_HYST_REG(chan->channel);
413 	default:
414 		return -EINVAL;
415 	}
416 
417 	return 0;
418 }
419 
420 static int ad799x_write_event_value(struct iio_dev *indio_dev,
421 				    const struct iio_chan_spec *chan,
422 				    enum iio_event_type type,
423 				    enum iio_event_direction dir,
424 				    enum iio_event_info info,
425 				    int val, int val2)
426 {
427 	int ret;
428 	struct ad799x_state *st = iio_priv(indio_dev);
429 
430 	mutex_lock(&indio_dev->mlock);
431 	ret = ad799x_i2c_write16(st, ad799x_threshold_reg(chan, dir, info),
432 		val);
433 	mutex_unlock(&indio_dev->mlock);
434 
435 	return ret;
436 }
437 
438 static int ad799x_read_event_value(struct iio_dev *indio_dev,
439 				    const struct iio_chan_spec *chan,
440 				    enum iio_event_type type,
441 				    enum iio_event_direction dir,
442 				    enum iio_event_info info,
443 				    int *val, int *val2)
444 {
445 	int ret;
446 	struct ad799x_state *st = iio_priv(indio_dev);
447 	u16 valin;
448 
449 	mutex_lock(&indio_dev->mlock);
450 	ret = ad799x_i2c_read16(st, ad799x_threshold_reg(chan, dir, info),
451 		&valin);
452 	mutex_unlock(&indio_dev->mlock);
453 	if (ret < 0)
454 		return ret;
455 	*val = valin;
456 
457 	return IIO_VAL_INT;
458 }
459 
460 static irqreturn_t ad799x_event_handler(int irq, void *private)
461 {
462 	struct iio_dev *indio_dev = private;
463 	struct ad799x_state *st = iio_priv(private);
464 	u8 status;
465 	int i, ret;
466 
467 	ret = ad799x_i2c_read8(st, AD7998_ALERT_STAT_REG, &status);
468 	if (ret)
469 		goto done;
470 
471 	if (!status)
472 		goto done;
473 
474 	ad799x_i2c_write8(st, AD7998_ALERT_STAT_REG, AD7998_ALERT_STAT_CLEAR);
475 
476 	for (i = 0; i < 8; i++) {
477 		if (status & (1 << i))
478 			iio_push_event(indio_dev,
479 				       i & 0x1 ?
480 				       IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
481 							    (i >> 1),
482 							    IIO_EV_TYPE_THRESH,
483 							    IIO_EV_DIR_RISING) :
484 				       IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
485 							    (i >> 1),
486 							    IIO_EV_TYPE_THRESH,
487 							    IIO_EV_DIR_FALLING),
488 				       iio_get_time_ns());
489 	}
490 
491 done:
492 	return IRQ_HANDLED;
493 }
494 
495 static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
496 			      ad799x_read_frequency,
497 			      ad799x_write_frequency);
498 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("15625 7812 3906 1953 976 488 244 0");
499 
500 static struct attribute *ad799x_event_attributes[] = {
501 	&iio_dev_attr_sampling_frequency.dev_attr.attr,
502 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
503 	NULL,
504 };
505 
506 static struct attribute_group ad799x_event_attrs_group = {
507 	.attrs = ad799x_event_attributes,
508 	.name = "events",
509 };
510 
511 static const struct iio_info ad7991_info = {
512 	.read_raw = &ad799x_read_raw,
513 	.driver_module = THIS_MODULE,
514 };
515 
516 static const struct iio_info ad7993_4_7_8_info = {
517 	.read_raw = &ad799x_read_raw,
518 	.event_attrs = &ad799x_event_attrs_group,
519 	.read_event_config = &ad799x_read_event_config,
520 	.read_event_value = &ad799x_read_event_value,
521 	.write_event_value = &ad799x_write_event_value,
522 	.driver_module = THIS_MODULE,
523 	.update_scan_mode = ad7997_8_update_scan_mode,
524 };
525 
526 static const struct iio_event_spec ad799x_events[] = {
527 	{
528 		.type = IIO_EV_TYPE_THRESH,
529 		.dir = IIO_EV_DIR_RISING,
530 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
531 			BIT(IIO_EV_INFO_ENABLE),
532 	}, {
533 		.type = IIO_EV_TYPE_THRESH,
534 		.dir = IIO_EV_DIR_FALLING,
535 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
536 			BIT(IIO_EV_INFO_ENABLE),
537 	}, {
538 		.type = IIO_EV_TYPE_THRESH,
539 		.dir = IIO_EV_DIR_EITHER,
540 		.mask_separate = BIT(IIO_EV_INFO_HYSTERESIS),
541 	},
542 };
543 
544 #define _AD799X_CHANNEL(_index, _realbits, _ev_spec, _num_ev_spec) { \
545 	.type = IIO_VOLTAGE, \
546 	.indexed = 1, \
547 	.channel = (_index), \
548 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
549 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
550 	.scan_index = (_index), \
551 	.scan_type = { \
552 		.sign = 'u', \
553 		.realbits = (_realbits), \
554 		.storagebits = 16, \
555 		.shift = 12 - (_realbits), \
556 		.endianness = IIO_BE, \
557 	}, \
558 	.event_spec = _ev_spec, \
559 	.num_event_specs = _num_ev_spec, \
560 }
561 
562 #define AD799X_CHANNEL(_index, _realbits) \
563 	_AD799X_CHANNEL(_index, _realbits, NULL, 0)
564 
565 #define AD799X_CHANNEL_WITH_EVENTS(_index, _realbits) \
566 	_AD799X_CHANNEL(_index, _realbits, ad799x_events, \
567 		ARRAY_SIZE(ad799x_events))
568 
569 static const struct ad799x_chip_info ad799x_chip_info_tbl[] = {
570 	[ad7991] = {
571 		.channel = {
572 			AD799X_CHANNEL(0, 12),
573 			AD799X_CHANNEL(1, 12),
574 			AD799X_CHANNEL(2, 12),
575 			AD799X_CHANNEL(3, 12),
576 			IIO_CHAN_SOFT_TIMESTAMP(4),
577 		},
578 		.num_channels = 5,
579 		.info = &ad7991_info,
580 	},
581 	[ad7995] = {
582 		.channel = {
583 			AD799X_CHANNEL(0, 10),
584 			AD799X_CHANNEL(1, 10),
585 			AD799X_CHANNEL(2, 10),
586 			AD799X_CHANNEL(3, 10),
587 			IIO_CHAN_SOFT_TIMESTAMP(4),
588 		},
589 		.num_channels = 5,
590 		.info = &ad7991_info,
591 	},
592 	[ad7999] = {
593 		.channel = {
594 			AD799X_CHANNEL(0, 8),
595 			AD799X_CHANNEL(1, 8),
596 			AD799X_CHANNEL(2, 8),
597 			AD799X_CHANNEL(3, 8),
598 			IIO_CHAN_SOFT_TIMESTAMP(4),
599 		},
600 		.num_channels = 5,
601 		.info = &ad7991_info,
602 	},
603 	[ad7992] = {
604 		.channel = {
605 			AD799X_CHANNEL_WITH_EVENTS(0, 12),
606 			AD799X_CHANNEL_WITH_EVENTS(1, 12),
607 			IIO_CHAN_SOFT_TIMESTAMP(3),
608 		},
609 		.num_channels = 3,
610 		.default_config = AD7998_ALERT_EN,
611 		.info = &ad7993_4_7_8_info,
612 	},
613 	[ad7993] = {
614 		.channel = {
615 			AD799X_CHANNEL_WITH_EVENTS(0, 10),
616 			AD799X_CHANNEL_WITH_EVENTS(1, 10),
617 			AD799X_CHANNEL_WITH_EVENTS(2, 10),
618 			AD799X_CHANNEL_WITH_EVENTS(3, 10),
619 			IIO_CHAN_SOFT_TIMESTAMP(4),
620 		},
621 		.num_channels = 5,
622 		.default_config = AD7998_ALERT_EN,
623 		.info = &ad7993_4_7_8_info,
624 	},
625 	[ad7994] = {
626 		.channel = {
627 			AD799X_CHANNEL_WITH_EVENTS(0, 12),
628 			AD799X_CHANNEL_WITH_EVENTS(1, 12),
629 			AD799X_CHANNEL_WITH_EVENTS(2, 12),
630 			AD799X_CHANNEL_WITH_EVENTS(3, 12),
631 			IIO_CHAN_SOFT_TIMESTAMP(4),
632 		},
633 		.num_channels = 5,
634 		.default_config = AD7998_ALERT_EN,
635 		.info = &ad7993_4_7_8_info,
636 	},
637 	[ad7997] = {
638 		.channel = {
639 			AD799X_CHANNEL_WITH_EVENTS(0, 10),
640 			AD799X_CHANNEL_WITH_EVENTS(1, 10),
641 			AD799X_CHANNEL_WITH_EVENTS(2, 10),
642 			AD799X_CHANNEL_WITH_EVENTS(3, 10),
643 			AD799X_CHANNEL(4, 10),
644 			AD799X_CHANNEL(5, 10),
645 			AD799X_CHANNEL(6, 10),
646 			AD799X_CHANNEL(7, 10),
647 			IIO_CHAN_SOFT_TIMESTAMP(8),
648 		},
649 		.num_channels = 9,
650 		.default_config = AD7998_ALERT_EN,
651 		.info = &ad7993_4_7_8_info,
652 	},
653 	[ad7998] = {
654 		.channel = {
655 			AD799X_CHANNEL_WITH_EVENTS(0, 12),
656 			AD799X_CHANNEL_WITH_EVENTS(1, 12),
657 			AD799X_CHANNEL_WITH_EVENTS(2, 12),
658 			AD799X_CHANNEL_WITH_EVENTS(3, 12),
659 			AD799X_CHANNEL(4, 12),
660 			AD799X_CHANNEL(5, 12),
661 			AD799X_CHANNEL(6, 12),
662 			AD799X_CHANNEL(7, 12),
663 			IIO_CHAN_SOFT_TIMESTAMP(8),
664 		},
665 		.num_channels = 9,
666 		.default_config = AD7998_ALERT_EN,
667 		.info = &ad7993_4_7_8_info,
668 	},
669 };
670 
671 static int ad799x_probe(struct i2c_client *client,
672 				   const struct i2c_device_id *id)
673 {
674 	int ret;
675 	struct ad799x_state *st;
676 	struct iio_dev *indio_dev;
677 
678 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
679 	if (indio_dev == NULL)
680 		return -ENOMEM;
681 
682 	st = iio_priv(indio_dev);
683 	/* this is only used for device removal purposes */
684 	i2c_set_clientdata(client, indio_dev);
685 
686 	st->id = id->driver_data;
687 	st->chip_info = &ad799x_chip_info_tbl[st->id];
688 	st->config = st->chip_info->default_config;
689 
690 	/* TODO: Add pdata options for filtering and bit delay */
691 
692 	st->reg = devm_regulator_get(&client->dev, "vcc");
693 	if (IS_ERR(st->reg))
694 		return PTR_ERR(st->reg);
695 	ret = regulator_enable(st->reg);
696 	if (ret)
697 		return ret;
698 	st->vref = devm_regulator_get(&client->dev, "vref");
699 	if (IS_ERR(st->vref)) {
700 		ret = PTR_ERR(st->vref);
701 		goto error_disable_reg;
702 	}
703 	ret = regulator_enable(st->vref);
704 	if (ret)
705 		goto error_disable_reg;
706 
707 	st->client = client;
708 
709 	indio_dev->dev.parent = &client->dev;
710 	indio_dev->name = id->name;
711 	indio_dev->info = st->chip_info->info;
712 
713 	indio_dev->modes = INDIO_DIRECT_MODE;
714 	indio_dev->channels = st->chip_info->channel;
715 	indio_dev->num_channels = st->chip_info->num_channels;
716 
717 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
718 		&ad799x_trigger_handler, NULL);
719 	if (ret)
720 		goto error_disable_vref;
721 
722 	if (client->irq > 0) {
723 		ret = devm_request_threaded_irq(&client->dev,
724 						client->irq,
725 						NULL,
726 						ad799x_event_handler,
727 						IRQF_TRIGGER_FALLING |
728 						IRQF_ONESHOT,
729 						client->name,
730 						indio_dev);
731 		if (ret)
732 			goto error_cleanup_ring;
733 	}
734 	ret = iio_device_register(indio_dev);
735 	if (ret)
736 		goto error_cleanup_ring;
737 
738 	return 0;
739 
740 error_cleanup_ring:
741 	iio_triggered_buffer_cleanup(indio_dev);
742 error_disable_vref:
743 	regulator_disable(st->vref);
744 error_disable_reg:
745 	regulator_disable(st->reg);
746 
747 	return ret;
748 }
749 
750 static int ad799x_remove(struct i2c_client *client)
751 {
752 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
753 	struct ad799x_state *st = iio_priv(indio_dev);
754 
755 	iio_device_unregister(indio_dev);
756 
757 	iio_triggered_buffer_cleanup(indio_dev);
758 	regulator_disable(st->vref);
759 	regulator_disable(st->reg);
760 	kfree(st->rx_buf);
761 
762 	return 0;
763 }
764 
765 static const struct i2c_device_id ad799x_id[] = {
766 	{ "ad7991", ad7991 },
767 	{ "ad7995", ad7995 },
768 	{ "ad7999", ad7999 },
769 	{ "ad7992", ad7992 },
770 	{ "ad7993", ad7993 },
771 	{ "ad7994", ad7994 },
772 	{ "ad7997", ad7997 },
773 	{ "ad7998", ad7998 },
774 	{}
775 };
776 
777 MODULE_DEVICE_TABLE(i2c, ad799x_id);
778 
779 static struct i2c_driver ad799x_driver = {
780 	.driver = {
781 		.name = "ad799x",
782 	},
783 	.probe = ad799x_probe,
784 	.remove = ad799x_remove,
785 	.id_table = ad799x_id,
786 };
787 module_i2c_driver(ad799x_driver);
788 
789 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
790 MODULE_DESCRIPTION("Analog Devices AD799x ADC");
791 MODULE_LICENSE("GPL v2");
792