xref: /openbmc/linux/drivers/iio/health/afe4403.c (revision a44e4f3a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * AFE4403 Heart Rate Monitors and Low-Cost Pulse Oximeters
4  *
5  * Copyright (C) 2015-2016 Texas Instruments Incorporated - http://www.ti.com/
6  *	Andrew F. Davis <afd@ti.com>
7  */
8 
9 #include <linux/device.h>
10 #include <linux/err.h>
11 #include <linux/interrupt.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/regmap.h>
15 #include <linux/spi/spi.h>
16 #include <linux/sysfs.h>
17 #include <linux/regulator/consumer.h>
18 
19 #include <linux/iio/iio.h>
20 #include <linux/iio/sysfs.h>
21 #include <linux/iio/buffer.h>
22 #include <linux/iio/trigger.h>
23 #include <linux/iio/triggered_buffer.h>
24 #include <linux/iio/trigger_consumer.h>
25 
26 #include "afe440x.h"
27 
28 #define AFE4403_DRIVER_NAME		"afe4403"
29 
30 /* AFE4403 Registers */
31 #define AFE4403_TIAGAIN			0x20
32 #define AFE4403_TIA_AMB_GAIN		0x21
33 
34 enum afe4403_fields {
35 	/* Gains */
36 	F_RF_LED1, F_CF_LED1,
37 	F_RF_LED, F_CF_LED,
38 
39 	/* LED Current */
40 	F_ILED1, F_ILED2,
41 
42 	/* sentinel */
43 	F_MAX_FIELDS
44 };
45 
46 static const struct reg_field afe4403_reg_fields[] = {
47 	/* Gains */
48 	[F_RF_LED1]	= REG_FIELD(AFE4403_TIAGAIN, 0, 2),
49 	[F_CF_LED1]	= REG_FIELD(AFE4403_TIAGAIN, 3, 7),
50 	[F_RF_LED]	= REG_FIELD(AFE4403_TIA_AMB_GAIN, 0, 2),
51 	[F_CF_LED]	= REG_FIELD(AFE4403_TIA_AMB_GAIN, 3, 7),
52 	/* LED Current */
53 	[F_ILED1]	= REG_FIELD(AFE440X_LEDCNTRL, 0, 7),
54 	[F_ILED2]	= REG_FIELD(AFE440X_LEDCNTRL, 8, 15),
55 };
56 
57 /**
58  * struct afe4403_data - AFE4403 device instance data
59  * @dev: Device structure
60  * @spi: SPI device handle
61  * @regmap: Register map of the device
62  * @fields: Register fields of the device
63  * @regulator: Pointer to the regulator for the IC
64  * @trig: IIO trigger for this device
65  * @irq: ADC_RDY line interrupt number
66  */
67 struct afe4403_data {
68 	struct device *dev;
69 	struct spi_device *spi;
70 	struct regmap *regmap;
71 	struct regmap_field *fields[F_MAX_FIELDS];
72 	struct regulator *regulator;
73 	struct iio_trigger *trig;
74 	int irq;
75 };
76 
77 enum afe4403_chan_id {
78 	LED2 = 1,
79 	ALED2,
80 	LED1,
81 	ALED1,
82 	LED2_ALED2,
83 	LED1_ALED1,
84 };
85 
86 static const unsigned int afe4403_channel_values[] = {
87 	[LED2] = AFE440X_LED2VAL,
88 	[ALED2] = AFE440X_ALED2VAL,
89 	[LED1] = AFE440X_LED1VAL,
90 	[ALED1] = AFE440X_ALED1VAL,
91 	[LED2_ALED2] = AFE440X_LED2_ALED2VAL,
92 	[LED1_ALED1] = AFE440X_LED1_ALED1VAL,
93 };
94 
95 static const unsigned int afe4403_channel_leds[] = {
96 	[LED2] = F_ILED2,
97 	[LED1] = F_ILED1,
98 };
99 
100 static const struct iio_chan_spec afe4403_channels[] = {
101 	/* ADC values */
102 	AFE440X_INTENSITY_CHAN(LED2, 0),
103 	AFE440X_INTENSITY_CHAN(ALED2, 0),
104 	AFE440X_INTENSITY_CHAN(LED1, 0),
105 	AFE440X_INTENSITY_CHAN(ALED1, 0),
106 	AFE440X_INTENSITY_CHAN(LED2_ALED2, 0),
107 	AFE440X_INTENSITY_CHAN(LED1_ALED1, 0),
108 	/* LED current */
109 	AFE440X_CURRENT_CHAN(LED2),
110 	AFE440X_CURRENT_CHAN(LED1),
111 };
112 
113 static const struct afe440x_val_table afe4403_res_table[] = {
114 	{ 500000 }, { 250000 }, { 100000 }, { 50000 },
115 	{ 25000 }, { 10000 }, { 1000000 }, { 0 },
116 };
117 AFE440X_TABLE_ATTR(in_intensity_resistance_available, afe4403_res_table);
118 
119 static const struct afe440x_val_table afe4403_cap_table[] = {
120 	{ 0, 5000 }, { 0, 10000 }, { 0, 20000 }, { 0, 25000 },
121 	{ 0, 30000 }, { 0, 35000 }, { 0, 45000 }, { 0, 50000 },
122 	{ 0, 55000 }, { 0, 60000 }, { 0, 70000 }, { 0, 75000 },
123 	{ 0, 80000 }, { 0, 85000 }, { 0, 95000 }, { 0, 100000 },
124 	{ 0, 155000 }, { 0, 160000 }, { 0, 170000 }, { 0, 175000 },
125 	{ 0, 180000 }, { 0, 185000 }, { 0, 195000 }, { 0, 200000 },
126 	{ 0, 205000 }, { 0, 210000 }, { 0, 220000 }, { 0, 225000 },
127 	{ 0, 230000 }, { 0, 235000 }, { 0, 245000 }, { 0, 250000 },
128 };
129 AFE440X_TABLE_ATTR(in_intensity_capacitance_available, afe4403_cap_table);
130 
131 static ssize_t afe440x_show_register(struct device *dev,
132 				     struct device_attribute *attr,
133 				     char *buf)
134 {
135 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
136 	struct afe4403_data *afe = iio_priv(indio_dev);
137 	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
138 	unsigned int reg_val;
139 	int vals[2];
140 	int ret;
141 
142 	ret = regmap_field_read(afe->fields[afe440x_attr->field], &reg_val);
143 	if (ret)
144 		return ret;
145 
146 	if (reg_val >= afe440x_attr->table_size)
147 		return -EINVAL;
148 
149 	vals[0] = afe440x_attr->val_table[reg_val].integer;
150 	vals[1] = afe440x_attr->val_table[reg_val].fract;
151 
152 	return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, 2, vals);
153 }
154 
155 static ssize_t afe440x_store_register(struct device *dev,
156 				      struct device_attribute *attr,
157 				      const char *buf, size_t count)
158 {
159 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
160 	struct afe4403_data *afe = iio_priv(indio_dev);
161 	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
162 	int val, integer, fract, ret;
163 
164 	ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
165 	if (ret)
166 		return ret;
167 
168 	for (val = 0; val < afe440x_attr->table_size; val++)
169 		if (afe440x_attr->val_table[val].integer == integer &&
170 		    afe440x_attr->val_table[val].fract == fract)
171 			break;
172 	if (val == afe440x_attr->table_size)
173 		return -EINVAL;
174 
175 	ret = regmap_field_write(afe->fields[afe440x_attr->field], val);
176 	if (ret)
177 		return ret;
178 
179 	return count;
180 }
181 
182 static AFE440X_ATTR(in_intensity1_resistance, F_RF_LED, afe4403_res_table);
183 static AFE440X_ATTR(in_intensity1_capacitance, F_CF_LED, afe4403_cap_table);
184 
185 static AFE440X_ATTR(in_intensity2_resistance, F_RF_LED, afe4403_res_table);
186 static AFE440X_ATTR(in_intensity2_capacitance, F_CF_LED, afe4403_cap_table);
187 
188 static AFE440X_ATTR(in_intensity3_resistance, F_RF_LED1, afe4403_res_table);
189 static AFE440X_ATTR(in_intensity3_capacitance, F_CF_LED1, afe4403_cap_table);
190 
191 static AFE440X_ATTR(in_intensity4_resistance, F_RF_LED1, afe4403_res_table);
192 static AFE440X_ATTR(in_intensity4_capacitance, F_CF_LED1, afe4403_cap_table);
193 
194 static struct attribute *afe440x_attributes[] = {
195 	&dev_attr_in_intensity_resistance_available.attr,
196 	&dev_attr_in_intensity_capacitance_available.attr,
197 	&afe440x_attr_in_intensity1_resistance.dev_attr.attr,
198 	&afe440x_attr_in_intensity1_capacitance.dev_attr.attr,
199 	&afe440x_attr_in_intensity2_resistance.dev_attr.attr,
200 	&afe440x_attr_in_intensity2_capacitance.dev_attr.attr,
201 	&afe440x_attr_in_intensity3_resistance.dev_attr.attr,
202 	&afe440x_attr_in_intensity3_capacitance.dev_attr.attr,
203 	&afe440x_attr_in_intensity4_resistance.dev_attr.attr,
204 	&afe440x_attr_in_intensity4_capacitance.dev_attr.attr,
205 	NULL
206 };
207 
208 static const struct attribute_group afe440x_attribute_group = {
209 	.attrs = afe440x_attributes
210 };
211 
212 static int afe4403_read(struct afe4403_data *afe, unsigned int reg, u32 *val)
213 {
214 	u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
215 	u8 rx[3];
216 	int ret;
217 
218 	/* Enable reading from the device */
219 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
220 	if (ret)
221 		return ret;
222 
223 	ret = spi_write_then_read(afe->spi, &reg, 1, rx, 3);
224 	if (ret)
225 		return ret;
226 
227 	*val = (rx[0] << 16) |
228 		(rx[1] << 8) |
229 		(rx[2]);
230 
231 	/* Disable reading from the device */
232 	tx[3] = AFE440X_CONTROL0_WRITE;
233 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
234 	if (ret)
235 		return ret;
236 
237 	return 0;
238 }
239 
240 static int afe4403_read_raw(struct iio_dev *indio_dev,
241 			    struct iio_chan_spec const *chan,
242 			    int *val, int *val2, long mask)
243 {
244 	struct afe4403_data *afe = iio_priv(indio_dev);
245 	unsigned int reg = afe4403_channel_values[chan->address];
246 	unsigned int field = afe4403_channel_leds[chan->address];
247 	int ret;
248 
249 	switch (chan->type) {
250 	case IIO_INTENSITY:
251 		switch (mask) {
252 		case IIO_CHAN_INFO_RAW:
253 			ret = afe4403_read(afe, reg, val);
254 			if (ret)
255 				return ret;
256 			return IIO_VAL_INT;
257 		}
258 		break;
259 	case IIO_CURRENT:
260 		switch (mask) {
261 		case IIO_CHAN_INFO_RAW:
262 			ret = regmap_field_read(afe->fields[field], val);
263 			if (ret)
264 				return ret;
265 			return IIO_VAL_INT;
266 		case IIO_CHAN_INFO_SCALE:
267 			*val = 0;
268 			*val2 = 800000;
269 			return IIO_VAL_INT_PLUS_MICRO;
270 		}
271 		break;
272 	default:
273 		break;
274 	}
275 
276 	return -EINVAL;
277 }
278 
279 static int afe4403_write_raw(struct iio_dev *indio_dev,
280 			     struct iio_chan_spec const *chan,
281 			     int val, int val2, long mask)
282 {
283 	struct afe4403_data *afe = iio_priv(indio_dev);
284 	unsigned int field = afe4403_channel_leds[chan->address];
285 
286 	switch (chan->type) {
287 	case IIO_CURRENT:
288 		switch (mask) {
289 		case IIO_CHAN_INFO_RAW:
290 			return regmap_field_write(afe->fields[field], val);
291 		}
292 		break;
293 	default:
294 		break;
295 	}
296 
297 	return -EINVAL;
298 }
299 
300 static const struct iio_info afe4403_iio_info = {
301 	.attrs = &afe440x_attribute_group,
302 	.read_raw = afe4403_read_raw,
303 	.write_raw = afe4403_write_raw,
304 };
305 
306 static irqreturn_t afe4403_trigger_handler(int irq, void *private)
307 {
308 	struct iio_poll_func *pf = private;
309 	struct iio_dev *indio_dev = pf->indio_dev;
310 	struct afe4403_data *afe = iio_priv(indio_dev);
311 	int ret, bit, i = 0;
312 	s32 buffer[8];
313 	u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
314 	u8 rx[3];
315 
316 	/* Enable reading from the device */
317 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
318 	if (ret)
319 		goto err;
320 
321 	for_each_set_bit(bit, indio_dev->active_scan_mask,
322 			 indio_dev->masklength) {
323 		ret = spi_write_then_read(afe->spi,
324 					  &afe4403_channel_values[bit], 1,
325 					  rx, 3);
326 		if (ret)
327 			goto err;
328 
329 		buffer[i++] = (rx[0] << 16) |
330 				(rx[1] << 8) |
331 				(rx[2]);
332 	}
333 
334 	/* Disable reading from the device */
335 	tx[3] = AFE440X_CONTROL0_WRITE;
336 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
337 	if (ret)
338 		goto err;
339 
340 	iio_push_to_buffers_with_timestamp(indio_dev, buffer, pf->timestamp);
341 err:
342 	iio_trigger_notify_done(indio_dev->trig);
343 
344 	return IRQ_HANDLED;
345 }
346 
347 static const struct iio_trigger_ops afe4403_trigger_ops = {
348 };
349 
350 #define AFE4403_TIMING_PAIRS			\
351 	{ AFE440X_LED2STC,	0x000050 },	\
352 	{ AFE440X_LED2ENDC,	0x0003e7 },	\
353 	{ AFE440X_LED1LEDSTC,	0x0007d0 },	\
354 	{ AFE440X_LED1LEDENDC,	0x000bb7 },	\
355 	{ AFE440X_ALED2STC,	0x000438 },	\
356 	{ AFE440X_ALED2ENDC,	0x0007cf },	\
357 	{ AFE440X_LED1STC,	0x000820 },	\
358 	{ AFE440X_LED1ENDC,	0x000bb7 },	\
359 	{ AFE440X_LED2LEDSTC,	0x000000 },	\
360 	{ AFE440X_LED2LEDENDC,	0x0003e7 },	\
361 	{ AFE440X_ALED1STC,	0x000c08 },	\
362 	{ AFE440X_ALED1ENDC,	0x000f9f },	\
363 	{ AFE440X_LED2CONVST,	0x0003ef },	\
364 	{ AFE440X_LED2CONVEND,	0x0007cf },	\
365 	{ AFE440X_ALED2CONVST,	0x0007d7 },	\
366 	{ AFE440X_ALED2CONVEND,	0x000bb7 },	\
367 	{ AFE440X_LED1CONVST,	0x000bbf },	\
368 	{ AFE440X_LED1CONVEND,	0x009c3f },	\
369 	{ AFE440X_ALED1CONVST,	0x000fa7 },	\
370 	{ AFE440X_ALED1CONVEND,	0x001387 },	\
371 	{ AFE440X_ADCRSTSTCT0,	0x0003e8 },	\
372 	{ AFE440X_ADCRSTENDCT0,	0x0003eb },	\
373 	{ AFE440X_ADCRSTSTCT1,	0x0007d0 },	\
374 	{ AFE440X_ADCRSTENDCT1,	0x0007d3 },	\
375 	{ AFE440X_ADCRSTSTCT2,	0x000bb8 },	\
376 	{ AFE440X_ADCRSTENDCT2,	0x000bbb },	\
377 	{ AFE440X_ADCRSTSTCT3,	0x000fa0 },	\
378 	{ AFE440X_ADCRSTENDCT3,	0x000fa3 },	\
379 	{ AFE440X_PRPCOUNT,	0x009c3f },	\
380 	{ AFE440X_PDNCYCLESTC,	0x001518 },	\
381 	{ AFE440X_PDNCYCLEENDC,	0x00991f }
382 
383 static const struct reg_sequence afe4403_reg_sequences[] = {
384 	AFE4403_TIMING_PAIRS,
385 	{ AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN },
386 	{ AFE4403_TIAGAIN, AFE440X_TIAGAIN_ENSEPGAIN },
387 };
388 
389 static const struct regmap_range afe4403_yes_ranges[] = {
390 	regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL),
391 };
392 
393 static const struct regmap_access_table afe4403_volatile_table = {
394 	.yes_ranges = afe4403_yes_ranges,
395 	.n_yes_ranges = ARRAY_SIZE(afe4403_yes_ranges),
396 };
397 
398 static const struct regmap_config afe4403_regmap_config = {
399 	.reg_bits = 8,
400 	.val_bits = 24,
401 
402 	.max_register = AFE440X_PDNCYCLEENDC,
403 	.cache_type = REGCACHE_RBTREE,
404 	.volatile_table = &afe4403_volatile_table,
405 };
406 
407 static const struct of_device_id afe4403_of_match[] = {
408 	{ .compatible = "ti,afe4403", },
409 	{ /* sentinel */ }
410 };
411 MODULE_DEVICE_TABLE(of, afe4403_of_match);
412 
413 static int __maybe_unused afe4403_suspend(struct device *dev)
414 {
415 	struct iio_dev *indio_dev = spi_get_drvdata(to_spi_device(dev));
416 	struct afe4403_data *afe = iio_priv(indio_dev);
417 	int ret;
418 
419 	ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
420 				 AFE440X_CONTROL2_PDN_AFE,
421 				 AFE440X_CONTROL2_PDN_AFE);
422 	if (ret)
423 		return ret;
424 
425 	ret = regulator_disable(afe->regulator);
426 	if (ret) {
427 		dev_err(dev, "Unable to disable regulator\n");
428 		return ret;
429 	}
430 
431 	return 0;
432 }
433 
434 static int __maybe_unused afe4403_resume(struct device *dev)
435 {
436 	struct iio_dev *indio_dev = spi_get_drvdata(to_spi_device(dev));
437 	struct afe4403_data *afe = iio_priv(indio_dev);
438 	int ret;
439 
440 	ret = regulator_enable(afe->regulator);
441 	if (ret) {
442 		dev_err(dev, "Unable to enable regulator\n");
443 		return ret;
444 	}
445 
446 	ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
447 				 AFE440X_CONTROL2_PDN_AFE, 0);
448 	if (ret)
449 		return ret;
450 
451 	return 0;
452 }
453 
454 static SIMPLE_DEV_PM_OPS(afe4403_pm_ops, afe4403_suspend, afe4403_resume);
455 
456 static int afe4403_probe(struct spi_device *spi)
457 {
458 	struct iio_dev *indio_dev;
459 	struct afe4403_data *afe;
460 	int i, ret;
461 
462 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*afe));
463 	if (!indio_dev)
464 		return -ENOMEM;
465 
466 	afe = iio_priv(indio_dev);
467 	spi_set_drvdata(spi, indio_dev);
468 
469 	afe->dev = &spi->dev;
470 	afe->spi = spi;
471 	afe->irq = spi->irq;
472 
473 	afe->regmap = devm_regmap_init_spi(spi, &afe4403_regmap_config);
474 	if (IS_ERR(afe->regmap)) {
475 		dev_err(afe->dev, "Unable to allocate register map\n");
476 		return PTR_ERR(afe->regmap);
477 	}
478 
479 	for (i = 0; i < F_MAX_FIELDS; i++) {
480 		afe->fields[i] = devm_regmap_field_alloc(afe->dev, afe->regmap,
481 							 afe4403_reg_fields[i]);
482 		if (IS_ERR(afe->fields[i])) {
483 			dev_err(afe->dev, "Unable to allocate regmap fields\n");
484 			return PTR_ERR(afe->fields[i]);
485 		}
486 	}
487 
488 	afe->regulator = devm_regulator_get(afe->dev, "tx_sup");
489 	if (IS_ERR(afe->regulator)) {
490 		dev_err(afe->dev, "Unable to get regulator\n");
491 		return PTR_ERR(afe->regulator);
492 	}
493 	ret = regulator_enable(afe->regulator);
494 	if (ret) {
495 		dev_err(afe->dev, "Unable to enable regulator\n");
496 		return ret;
497 	}
498 
499 	ret = regmap_write(afe->regmap, AFE440X_CONTROL0,
500 			   AFE440X_CONTROL0_SW_RESET);
501 	if (ret) {
502 		dev_err(afe->dev, "Unable to reset device\n");
503 		goto err_disable_reg;
504 	}
505 
506 	ret = regmap_multi_reg_write(afe->regmap, afe4403_reg_sequences,
507 				     ARRAY_SIZE(afe4403_reg_sequences));
508 	if (ret) {
509 		dev_err(afe->dev, "Unable to set register defaults\n");
510 		goto err_disable_reg;
511 	}
512 
513 	indio_dev->modes = INDIO_DIRECT_MODE;
514 	indio_dev->dev.parent = afe->dev;
515 	indio_dev->channels = afe4403_channels;
516 	indio_dev->num_channels = ARRAY_SIZE(afe4403_channels);
517 	indio_dev->name = AFE4403_DRIVER_NAME;
518 	indio_dev->info = &afe4403_iio_info;
519 
520 	if (afe->irq > 0) {
521 		afe->trig = devm_iio_trigger_alloc(afe->dev,
522 						   "%s-dev%d",
523 						   indio_dev->name,
524 						   indio_dev->id);
525 		if (!afe->trig) {
526 			dev_err(afe->dev, "Unable to allocate IIO trigger\n");
527 			ret = -ENOMEM;
528 			goto err_disable_reg;
529 		}
530 
531 		iio_trigger_set_drvdata(afe->trig, indio_dev);
532 
533 		afe->trig->ops = &afe4403_trigger_ops;
534 		afe->trig->dev.parent = afe->dev;
535 
536 		ret = iio_trigger_register(afe->trig);
537 		if (ret) {
538 			dev_err(afe->dev, "Unable to register IIO trigger\n");
539 			goto err_disable_reg;
540 		}
541 
542 		ret = devm_request_threaded_irq(afe->dev, afe->irq,
543 						iio_trigger_generic_data_rdy_poll,
544 						NULL, IRQF_ONESHOT,
545 						AFE4403_DRIVER_NAME,
546 						afe->trig);
547 		if (ret) {
548 			dev_err(afe->dev, "Unable to request IRQ\n");
549 			goto err_trig;
550 		}
551 	}
552 
553 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
554 					 afe4403_trigger_handler, NULL);
555 	if (ret) {
556 		dev_err(afe->dev, "Unable to setup buffer\n");
557 		goto err_trig;
558 	}
559 
560 	ret = iio_device_register(indio_dev);
561 	if (ret) {
562 		dev_err(afe->dev, "Unable to register IIO device\n");
563 		goto err_buff;
564 	}
565 
566 	return 0;
567 
568 err_buff:
569 	iio_triggered_buffer_cleanup(indio_dev);
570 err_trig:
571 	if (afe->irq > 0)
572 		iio_trigger_unregister(afe->trig);
573 err_disable_reg:
574 	regulator_disable(afe->regulator);
575 
576 	return ret;
577 }
578 
579 static int afe4403_remove(struct spi_device *spi)
580 {
581 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
582 	struct afe4403_data *afe = iio_priv(indio_dev);
583 	int ret;
584 
585 	iio_device_unregister(indio_dev);
586 
587 	iio_triggered_buffer_cleanup(indio_dev);
588 
589 	if (afe->irq > 0)
590 		iio_trigger_unregister(afe->trig);
591 
592 	ret = regulator_disable(afe->regulator);
593 	if (ret) {
594 		dev_err(afe->dev, "Unable to disable regulator\n");
595 		return ret;
596 	}
597 
598 	return 0;
599 }
600 
601 static const struct spi_device_id afe4403_ids[] = {
602 	{ "afe4403", 0 },
603 	{ /* sentinel */ }
604 };
605 MODULE_DEVICE_TABLE(spi, afe4403_ids);
606 
607 static struct spi_driver afe4403_spi_driver = {
608 	.driver = {
609 		.name = AFE4403_DRIVER_NAME,
610 		.of_match_table = afe4403_of_match,
611 		.pm = &afe4403_pm_ops,
612 	},
613 	.probe = afe4403_probe,
614 	.remove = afe4403_remove,
615 	.id_table = afe4403_ids,
616 };
617 module_spi_driver(afe4403_spi_driver);
618 
619 MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
620 MODULE_DESCRIPTION("TI AFE4403 Heart Rate Monitor and Pulse Oximeter AFE");
621 MODULE_LICENSE("GPL v2");
622