xref: /linux/drivers/iio/adc/ad7768-1.c (revision 172cdcaefea5c297fdb3d20b7d5aff60ae4fbce6)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Analog Devices AD7768-1 SPI ADC driver
4  *
5  * Copyright 2017 Analog Devices Inc.
6  */
7 #include <linux/bitfield.h>
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/device.h>
11 #include <linux/err.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/regulator/consumer.h>
16 #include <linux/sysfs.h>
17 #include <linux/spi/spi.h>
18 
19 #include <linux/iio/buffer.h>
20 #include <linux/iio/iio.h>
21 #include <linux/iio/sysfs.h>
22 #include <linux/iio/trigger.h>
23 #include <linux/iio/triggered_buffer.h>
24 #include <linux/iio/trigger_consumer.h>
25 
26 /* AD7768 registers definition */
27 #define AD7768_REG_CHIP_TYPE		0x3
28 #define AD7768_REG_PROD_ID_L		0x4
29 #define AD7768_REG_PROD_ID_H		0x5
30 #define AD7768_REG_CHIP_GRADE		0x6
31 #define AD7768_REG_SCRATCH_PAD		0x0A
32 #define AD7768_REG_VENDOR_L		0x0C
33 #define AD7768_REG_VENDOR_H		0x0D
34 #define AD7768_REG_INTERFACE_FORMAT	0x14
35 #define AD7768_REG_POWER_CLOCK		0x15
36 #define AD7768_REG_ANALOG		0x16
37 #define AD7768_REG_ANALOG2		0x17
38 #define AD7768_REG_CONVERSION		0x18
39 #define AD7768_REG_DIGITAL_FILTER	0x19
40 #define AD7768_REG_SINC3_DEC_RATE_MSB	0x1A
41 #define AD7768_REG_SINC3_DEC_RATE_LSB	0x1B
42 #define AD7768_REG_DUTY_CYCLE_RATIO	0x1C
43 #define AD7768_REG_SYNC_RESET		0x1D
44 #define AD7768_REG_GPIO_CONTROL		0x1E
45 #define AD7768_REG_GPIO_WRITE		0x1F
46 #define AD7768_REG_GPIO_READ		0x20
47 #define AD7768_REG_OFFSET_HI		0x21
48 #define AD7768_REG_OFFSET_MID		0x22
49 #define AD7768_REG_OFFSET_LO		0x23
50 #define AD7768_REG_GAIN_HI		0x24
51 #define AD7768_REG_GAIN_MID		0x25
52 #define AD7768_REG_GAIN_LO		0x26
53 #define AD7768_REG_SPI_DIAG_ENABLE	0x28
54 #define AD7768_REG_ADC_DIAG_ENABLE	0x29
55 #define AD7768_REG_DIG_DIAG_ENABLE	0x2A
56 #define AD7768_REG_ADC_DATA		0x2C
57 #define AD7768_REG_MASTER_STATUS	0x2D
58 #define AD7768_REG_SPI_DIAG_STATUS	0x2E
59 #define AD7768_REG_ADC_DIAG_STATUS	0x2F
60 #define AD7768_REG_DIG_DIAG_STATUS	0x30
61 #define AD7768_REG_MCLK_COUNTER		0x31
62 
63 /* AD7768_REG_POWER_CLOCK */
64 #define AD7768_PWR_MCLK_DIV_MSK		GENMASK(5, 4)
65 #define AD7768_PWR_MCLK_DIV(x)		FIELD_PREP(AD7768_PWR_MCLK_DIV_MSK, x)
66 #define AD7768_PWR_PWRMODE_MSK		GENMASK(1, 0)
67 #define AD7768_PWR_PWRMODE(x)		FIELD_PREP(AD7768_PWR_PWRMODE_MSK, x)
68 
69 /* AD7768_REG_DIGITAL_FILTER */
70 #define AD7768_DIG_FIL_FIL_MSK		GENMASK(6, 4)
71 #define AD7768_DIG_FIL_FIL(x)		FIELD_PREP(AD7768_DIG_FIL_FIL_MSK, x)
72 #define AD7768_DIG_FIL_DEC_MSK		GENMASK(2, 0)
73 #define AD7768_DIG_FIL_DEC_RATE(x)	FIELD_PREP(AD7768_DIG_FIL_DEC_MSK, x)
74 
75 /* AD7768_REG_CONVERSION */
76 #define AD7768_CONV_MODE_MSK		GENMASK(2, 0)
77 #define AD7768_CONV_MODE(x)		FIELD_PREP(AD7768_CONV_MODE_MSK, x)
78 
79 #define AD7768_RD_FLAG_MSK(x)		(BIT(6) | ((x) & 0x3F))
80 #define AD7768_WR_FLAG_MSK(x)		((x) & 0x3F)
81 
82 enum ad7768_conv_mode {
83 	AD7768_CONTINUOUS,
84 	AD7768_ONE_SHOT,
85 	AD7768_SINGLE,
86 	AD7768_PERIODIC,
87 	AD7768_STANDBY
88 };
89 
90 enum ad7768_pwrmode {
91 	AD7768_ECO_MODE = 0,
92 	AD7768_MED_MODE = 2,
93 	AD7768_FAST_MODE = 3
94 };
95 
96 enum ad7768_mclk_div {
97 	AD7768_MCLK_DIV_16,
98 	AD7768_MCLK_DIV_8,
99 	AD7768_MCLK_DIV_4,
100 	AD7768_MCLK_DIV_2
101 };
102 
103 enum ad7768_dec_rate {
104 	AD7768_DEC_RATE_32 = 0,
105 	AD7768_DEC_RATE_64 = 1,
106 	AD7768_DEC_RATE_128 = 2,
107 	AD7768_DEC_RATE_256 = 3,
108 	AD7768_DEC_RATE_512 = 4,
109 	AD7768_DEC_RATE_1024 = 5,
110 	AD7768_DEC_RATE_8 = 9,
111 	AD7768_DEC_RATE_16 = 10
112 };
113 
114 struct ad7768_clk_configuration {
115 	enum ad7768_mclk_div mclk_div;
116 	enum ad7768_dec_rate dec_rate;
117 	unsigned int clk_div;
118 	enum ad7768_pwrmode pwrmode;
119 };
120 
121 static const struct ad7768_clk_configuration ad7768_clk_config[] = {
122 	{ AD7768_MCLK_DIV_2, AD7768_DEC_RATE_8, 16,  AD7768_FAST_MODE },
123 	{ AD7768_MCLK_DIV_2, AD7768_DEC_RATE_16, 32,  AD7768_FAST_MODE },
124 	{ AD7768_MCLK_DIV_2, AD7768_DEC_RATE_32, 64, AD7768_FAST_MODE },
125 	{ AD7768_MCLK_DIV_2, AD7768_DEC_RATE_64, 128, AD7768_FAST_MODE },
126 	{ AD7768_MCLK_DIV_2, AD7768_DEC_RATE_128, 256, AD7768_FAST_MODE },
127 	{ AD7768_MCLK_DIV_4, AD7768_DEC_RATE_128, 512, AD7768_MED_MODE },
128 	{ AD7768_MCLK_DIV_4, AD7768_DEC_RATE_256, 1024, AD7768_MED_MODE },
129 	{ AD7768_MCLK_DIV_4, AD7768_DEC_RATE_512, 2048, AD7768_MED_MODE },
130 	{ AD7768_MCLK_DIV_4, AD7768_DEC_RATE_1024, 4096, AD7768_MED_MODE },
131 	{ AD7768_MCLK_DIV_8, AD7768_DEC_RATE_1024, 8192, AD7768_MED_MODE },
132 	{ AD7768_MCLK_DIV_16, AD7768_DEC_RATE_1024, 16384, AD7768_ECO_MODE },
133 };
134 
135 static const struct iio_chan_spec ad7768_channels[] = {
136 	{
137 		.type = IIO_VOLTAGE,
138 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
139 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
140 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
141 		.indexed = 1,
142 		.channel = 0,
143 		.scan_index = 0,
144 		.scan_type = {
145 			.sign = 'u',
146 			.realbits = 24,
147 			.storagebits = 32,
148 			.shift = 8,
149 			.endianness = IIO_BE,
150 		},
151 	},
152 };
153 
154 struct ad7768_state {
155 	struct spi_device *spi;
156 	struct regulator *vref;
157 	struct mutex lock;
158 	struct clk *mclk;
159 	unsigned int mclk_freq;
160 	unsigned int samp_freq;
161 	struct completion completion;
162 	struct iio_trigger *trig;
163 	struct gpio_desc *gpio_sync_in;
164 	const char *labels[ARRAY_SIZE(ad7768_channels)];
165 	/*
166 	 * DMA (thus cache coherency maintenance) requires the
167 	 * transfer buffers to live in their own cache lines.
168 	 */
169 	union {
170 		__be32 d32;
171 		u8 d8[2];
172 	} data ____cacheline_aligned;
173 };
174 
175 static int ad7768_spi_reg_read(struct ad7768_state *st, unsigned int addr,
176 			       unsigned int len)
177 {
178 	unsigned int shift;
179 	int ret;
180 
181 	shift = 32 - (8 * len);
182 	st->data.d8[0] = AD7768_RD_FLAG_MSK(addr);
183 
184 	ret = spi_write_then_read(st->spi, st->data.d8, 1,
185 				  &st->data.d32, len);
186 	if (ret < 0)
187 		return ret;
188 
189 	return (be32_to_cpu(st->data.d32) >> shift);
190 }
191 
192 static int ad7768_spi_reg_write(struct ad7768_state *st,
193 				unsigned int addr,
194 				unsigned int val)
195 {
196 	st->data.d8[0] = AD7768_WR_FLAG_MSK(addr);
197 	st->data.d8[1] = val & 0xFF;
198 
199 	return spi_write(st->spi, st->data.d8, 2);
200 }
201 
202 static int ad7768_set_mode(struct ad7768_state *st,
203 			   enum ad7768_conv_mode mode)
204 {
205 	int regval;
206 
207 	regval = ad7768_spi_reg_read(st, AD7768_REG_CONVERSION, 1);
208 	if (regval < 0)
209 		return regval;
210 
211 	regval &= ~AD7768_CONV_MODE_MSK;
212 	regval |= AD7768_CONV_MODE(mode);
213 
214 	return ad7768_spi_reg_write(st, AD7768_REG_CONVERSION, regval);
215 }
216 
217 static int ad7768_scan_direct(struct iio_dev *indio_dev)
218 {
219 	struct ad7768_state *st = iio_priv(indio_dev);
220 	int readval, ret;
221 
222 	reinit_completion(&st->completion);
223 
224 	ret = ad7768_set_mode(st, AD7768_ONE_SHOT);
225 	if (ret < 0)
226 		return ret;
227 
228 	ret = wait_for_completion_timeout(&st->completion,
229 					  msecs_to_jiffies(1000));
230 	if (!ret)
231 		return -ETIMEDOUT;
232 
233 	readval = ad7768_spi_reg_read(st, AD7768_REG_ADC_DATA, 3);
234 	if (readval < 0)
235 		return readval;
236 	/*
237 	 * Any SPI configuration of the AD7768-1 can only be
238 	 * performed in continuous conversion mode.
239 	 */
240 	ret = ad7768_set_mode(st, AD7768_CONTINUOUS);
241 	if (ret < 0)
242 		return ret;
243 
244 	return readval;
245 }
246 
247 static int ad7768_reg_access(struct iio_dev *indio_dev,
248 			     unsigned int reg,
249 			     unsigned int writeval,
250 			     unsigned int *readval)
251 {
252 	struct ad7768_state *st = iio_priv(indio_dev);
253 	int ret;
254 
255 	mutex_lock(&st->lock);
256 	if (readval) {
257 		ret = ad7768_spi_reg_read(st, reg, 1);
258 		if (ret < 0)
259 			goto err_unlock;
260 		*readval = ret;
261 		ret = 0;
262 	} else {
263 		ret = ad7768_spi_reg_write(st, reg, writeval);
264 	}
265 err_unlock:
266 	mutex_unlock(&st->lock);
267 
268 	return ret;
269 }
270 
271 static int ad7768_set_dig_fil(struct ad7768_state *st,
272 			      enum ad7768_dec_rate dec_rate)
273 {
274 	unsigned int mode;
275 	int ret;
276 
277 	if (dec_rate == AD7768_DEC_RATE_8 || dec_rate == AD7768_DEC_RATE_16)
278 		mode = AD7768_DIG_FIL_FIL(dec_rate);
279 	else
280 		mode = AD7768_DIG_FIL_DEC_RATE(dec_rate);
281 
282 	ret = ad7768_spi_reg_write(st, AD7768_REG_DIGITAL_FILTER, mode);
283 	if (ret < 0)
284 		return ret;
285 
286 	/* A sync-in pulse is required every time the filter dec rate changes */
287 	gpiod_set_value(st->gpio_sync_in, 1);
288 	gpiod_set_value(st->gpio_sync_in, 0);
289 
290 	return 0;
291 }
292 
293 static int ad7768_set_freq(struct ad7768_state *st,
294 			   unsigned int freq)
295 {
296 	unsigned int diff_new, diff_old, pwr_mode, i, idx;
297 	int res, ret;
298 
299 	diff_old = U32_MAX;
300 	idx = 0;
301 
302 	res = DIV_ROUND_CLOSEST(st->mclk_freq, freq);
303 
304 	/* Find the closest match for the desired sampling frequency */
305 	for (i = 0; i < ARRAY_SIZE(ad7768_clk_config); i++) {
306 		diff_new = abs(res - ad7768_clk_config[i].clk_div);
307 		if (diff_new < diff_old) {
308 			diff_old = diff_new;
309 			idx = i;
310 		}
311 	}
312 
313 	/*
314 	 * Set both the mclk_div and pwrmode with a single write to the
315 	 * POWER_CLOCK register
316 	 */
317 	pwr_mode = AD7768_PWR_MCLK_DIV(ad7768_clk_config[idx].mclk_div) |
318 		   AD7768_PWR_PWRMODE(ad7768_clk_config[idx].pwrmode);
319 	ret = ad7768_spi_reg_write(st, AD7768_REG_POWER_CLOCK, pwr_mode);
320 	if (ret < 0)
321 		return ret;
322 
323 	ret =  ad7768_set_dig_fil(st, ad7768_clk_config[idx].dec_rate);
324 	if (ret < 0)
325 		return ret;
326 
327 	st->samp_freq = DIV_ROUND_CLOSEST(st->mclk_freq,
328 					  ad7768_clk_config[idx].clk_div);
329 
330 	return 0;
331 }
332 
333 static ssize_t ad7768_sampling_freq_avail(struct device *dev,
334 					  struct device_attribute *attr,
335 					  char *buf)
336 {
337 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
338 	struct ad7768_state *st = iio_priv(indio_dev);
339 	unsigned int freq;
340 	int i, len = 0;
341 
342 	for (i = 0; i < ARRAY_SIZE(ad7768_clk_config); i++) {
343 		freq = DIV_ROUND_CLOSEST(st->mclk_freq,
344 					 ad7768_clk_config[i].clk_div);
345 		len += scnprintf(buf + len, PAGE_SIZE - len, "%d ", freq);
346 	}
347 
348 	buf[len - 1] = '\n';
349 
350 	return len;
351 }
352 
353 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(ad7768_sampling_freq_avail);
354 
355 static int ad7768_read_raw(struct iio_dev *indio_dev,
356 			   struct iio_chan_spec const *chan,
357 			   int *val, int *val2, long info)
358 {
359 	struct ad7768_state *st = iio_priv(indio_dev);
360 	int scale_uv, ret;
361 
362 	switch (info) {
363 	case IIO_CHAN_INFO_RAW:
364 		ret = iio_device_claim_direct_mode(indio_dev);
365 		if (ret)
366 			return ret;
367 
368 		ret = ad7768_scan_direct(indio_dev);
369 		if (ret >= 0)
370 			*val = ret;
371 
372 		iio_device_release_direct_mode(indio_dev);
373 		if (ret < 0)
374 			return ret;
375 
376 		return IIO_VAL_INT;
377 
378 	case IIO_CHAN_INFO_SCALE:
379 		scale_uv = regulator_get_voltage(st->vref);
380 		if (scale_uv < 0)
381 			return scale_uv;
382 
383 		*val = (scale_uv * 2) / 1000;
384 		*val2 = chan->scan_type.realbits;
385 
386 		return IIO_VAL_FRACTIONAL_LOG2;
387 
388 	case IIO_CHAN_INFO_SAMP_FREQ:
389 		*val = st->samp_freq;
390 
391 		return IIO_VAL_INT;
392 	}
393 
394 	return -EINVAL;
395 }
396 
397 static int ad7768_write_raw(struct iio_dev *indio_dev,
398 			    struct iio_chan_spec const *chan,
399 			    int val, int val2, long info)
400 {
401 	struct ad7768_state *st = iio_priv(indio_dev);
402 
403 	switch (info) {
404 	case IIO_CHAN_INFO_SAMP_FREQ:
405 		return ad7768_set_freq(st, val);
406 	default:
407 		return -EINVAL;
408 	}
409 }
410 
411 static int ad7768_read_label(struct iio_dev *indio_dev,
412 	const struct iio_chan_spec *chan, char *label)
413 {
414 	struct ad7768_state *st = iio_priv(indio_dev);
415 
416 	return sprintf(label, "%s\n", st->labels[chan->channel]);
417 }
418 
419 static struct attribute *ad7768_attributes[] = {
420 	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
421 	NULL
422 };
423 
424 static const struct attribute_group ad7768_group = {
425 	.attrs = ad7768_attributes,
426 };
427 
428 static const struct iio_info ad7768_info = {
429 	.attrs = &ad7768_group,
430 	.read_raw = &ad7768_read_raw,
431 	.write_raw = &ad7768_write_raw,
432 	.read_label = ad7768_read_label,
433 	.debugfs_reg_access = &ad7768_reg_access,
434 };
435 
436 static int ad7768_setup(struct ad7768_state *st)
437 {
438 	int ret;
439 
440 	/*
441 	 * Two writes to the SPI_RESET[1:0] bits are required to initiate
442 	 * a software reset. The bits must first be set to 11, and then
443 	 * to 10. When the sequence is detected, the reset occurs.
444 	 * See the datasheet, page 70.
445 	 */
446 	ret = ad7768_spi_reg_write(st, AD7768_REG_SYNC_RESET, 0x3);
447 	if (ret)
448 		return ret;
449 
450 	ret = ad7768_spi_reg_write(st, AD7768_REG_SYNC_RESET, 0x2);
451 	if (ret)
452 		return ret;
453 
454 	st->gpio_sync_in = devm_gpiod_get(&st->spi->dev, "adi,sync-in",
455 					  GPIOD_OUT_LOW);
456 	if (IS_ERR(st->gpio_sync_in))
457 		return PTR_ERR(st->gpio_sync_in);
458 
459 	/* Set the default sampling frequency to 32000 kSPS */
460 	return ad7768_set_freq(st, 32000);
461 }
462 
463 static irqreturn_t ad7768_trigger_handler(int irq, void *p)
464 {
465 	struct iio_poll_func *pf = p;
466 	struct iio_dev *indio_dev = pf->indio_dev;
467 	struct ad7768_state *st = iio_priv(indio_dev);
468 	int ret;
469 
470 	mutex_lock(&st->lock);
471 
472 	ret = spi_read(st->spi, &st->data.d32, 3);
473 	if (ret < 0)
474 		goto err_unlock;
475 
476 	iio_push_to_buffers_with_timestamp(indio_dev, &st->data.d32,
477 					   iio_get_time_ns(indio_dev));
478 
479 	iio_trigger_notify_done(indio_dev->trig);
480 err_unlock:
481 	mutex_unlock(&st->lock);
482 
483 	return IRQ_HANDLED;
484 }
485 
486 static irqreturn_t ad7768_interrupt(int irq, void *dev_id)
487 {
488 	struct iio_dev *indio_dev = dev_id;
489 	struct ad7768_state *st = iio_priv(indio_dev);
490 
491 	if (iio_buffer_enabled(indio_dev))
492 		iio_trigger_poll(st->trig);
493 	else
494 		complete(&st->completion);
495 
496 	return IRQ_HANDLED;
497 };
498 
499 static int ad7768_buffer_postenable(struct iio_dev *indio_dev)
500 {
501 	struct ad7768_state *st = iio_priv(indio_dev);
502 
503 	/*
504 	 * Write a 1 to the LSB of the INTERFACE_FORMAT register to enter
505 	 * continuous read mode. Subsequent data reads do not require an
506 	 * initial 8-bit write to query the ADC_DATA register.
507 	 */
508 	return ad7768_spi_reg_write(st, AD7768_REG_INTERFACE_FORMAT, 0x01);
509 }
510 
511 static int ad7768_buffer_predisable(struct iio_dev *indio_dev)
512 {
513 	struct ad7768_state *st = iio_priv(indio_dev);
514 
515 	/*
516 	 * To exit continuous read mode, perform a single read of the ADC_DATA
517 	 * reg (0x2C), which allows further configuration of the device.
518 	 */
519 	return ad7768_spi_reg_read(st, AD7768_REG_ADC_DATA, 3);
520 }
521 
522 static const struct iio_buffer_setup_ops ad7768_buffer_ops = {
523 	.postenable = &ad7768_buffer_postenable,
524 	.predisable = &ad7768_buffer_predisable,
525 };
526 
527 static const struct iio_trigger_ops ad7768_trigger_ops = {
528 	.validate_device = iio_trigger_validate_own_device,
529 };
530 
531 static void ad7768_regulator_disable(void *data)
532 {
533 	struct ad7768_state *st = data;
534 
535 	regulator_disable(st->vref);
536 }
537 
538 static void ad7768_clk_disable(void *data)
539 {
540 	struct ad7768_state *st = data;
541 
542 	clk_disable_unprepare(st->mclk);
543 }
544 
545 static int ad7768_set_channel_label(struct iio_dev *indio_dev,
546 						int num_channels)
547 {
548 	struct ad7768_state *st = iio_priv(indio_dev);
549 	struct device *device = indio_dev->dev.parent;
550 	struct fwnode_handle *fwnode;
551 	struct fwnode_handle *child;
552 	const char *label;
553 	int crt_ch = 0;
554 
555 	fwnode = dev_fwnode(device);
556 	fwnode_for_each_child_node(fwnode, child) {
557 		if (fwnode_property_read_u32(child, "reg", &crt_ch))
558 			continue;
559 
560 		if (crt_ch >= num_channels)
561 			continue;
562 
563 		if (fwnode_property_read_string(child, "label", &label))
564 			continue;
565 
566 		st->labels[crt_ch] = label;
567 	}
568 
569 	return 0;
570 }
571 
572 static int ad7768_probe(struct spi_device *spi)
573 {
574 	struct ad7768_state *st;
575 	struct iio_dev *indio_dev;
576 	int ret;
577 
578 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
579 	if (!indio_dev)
580 		return -ENOMEM;
581 
582 	st = iio_priv(indio_dev);
583 	st->spi = spi;
584 
585 	st->vref = devm_regulator_get(&spi->dev, "vref");
586 	if (IS_ERR(st->vref))
587 		return PTR_ERR(st->vref);
588 
589 	ret = regulator_enable(st->vref);
590 	if (ret) {
591 		dev_err(&spi->dev, "Failed to enable specified vref supply\n");
592 		return ret;
593 	}
594 
595 	ret = devm_add_action_or_reset(&spi->dev, ad7768_regulator_disable, st);
596 	if (ret)
597 		return ret;
598 
599 	st->mclk = devm_clk_get(&spi->dev, "mclk");
600 	if (IS_ERR(st->mclk))
601 		return PTR_ERR(st->mclk);
602 
603 	ret = clk_prepare_enable(st->mclk);
604 	if (ret < 0)
605 		return ret;
606 
607 	ret = devm_add_action_or_reset(&spi->dev, ad7768_clk_disable, st);
608 	if (ret)
609 		return ret;
610 
611 	st->mclk_freq = clk_get_rate(st->mclk);
612 
613 	spi_set_drvdata(spi, indio_dev);
614 	mutex_init(&st->lock);
615 
616 	indio_dev->channels = ad7768_channels;
617 	indio_dev->num_channels = ARRAY_SIZE(ad7768_channels);
618 	indio_dev->name = spi_get_device_id(spi)->name;
619 	indio_dev->info = &ad7768_info;
620 	indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_TRIGGERED;
621 
622 	ret = ad7768_setup(st);
623 	if (ret < 0) {
624 		dev_err(&spi->dev, "AD7768 setup failed\n");
625 		return ret;
626 	}
627 
628 	st->trig = devm_iio_trigger_alloc(&spi->dev, "%s-dev%d",
629 					  indio_dev->name, indio_dev->id);
630 	if (!st->trig)
631 		return -ENOMEM;
632 
633 	st->trig->ops = &ad7768_trigger_ops;
634 	iio_trigger_set_drvdata(st->trig, indio_dev);
635 	ret = devm_iio_trigger_register(&spi->dev, st->trig);
636 	if (ret)
637 		return ret;
638 
639 	indio_dev->trig = iio_trigger_get(st->trig);
640 
641 	init_completion(&st->completion);
642 
643 	ret = ad7768_set_channel_label(indio_dev, ARRAY_SIZE(ad7768_channels));
644 	if (ret)
645 		return ret;
646 
647 	ret = devm_request_irq(&spi->dev, spi->irq,
648 			       &ad7768_interrupt,
649 			       IRQF_TRIGGER_RISING | IRQF_ONESHOT,
650 			       indio_dev->name, indio_dev);
651 	if (ret)
652 		return ret;
653 
654 	ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
655 					      &iio_pollfunc_store_time,
656 					      &ad7768_trigger_handler,
657 					      &ad7768_buffer_ops);
658 	if (ret)
659 		return ret;
660 
661 	return devm_iio_device_register(&spi->dev, indio_dev);
662 }
663 
664 static const struct spi_device_id ad7768_id_table[] = {
665 	{ "ad7768-1", 0 },
666 	{}
667 };
668 MODULE_DEVICE_TABLE(spi, ad7768_id_table);
669 
670 static const struct of_device_id ad7768_of_match[] = {
671 	{ .compatible = "adi,ad7768-1" },
672 	{ },
673 };
674 MODULE_DEVICE_TABLE(of, ad7768_of_match);
675 
676 static struct spi_driver ad7768_driver = {
677 	.driver = {
678 		.name = "ad7768-1",
679 		.of_match_table = ad7768_of_match,
680 	},
681 	.probe = ad7768_probe,
682 	.id_table = ad7768_id_table,
683 };
684 module_spi_driver(ad7768_driver);
685 
686 MODULE_AUTHOR("Stefan Popa <stefan.popa@analog.com>");
687 MODULE_DESCRIPTION("Analog Devices AD7768-1 ADC driver");
688 MODULE_LICENSE("GPL v2");
689