xref: /openbmc/linux/drivers/iio/health/afe4403.c (revision 8730046c)
1 /*
2  * AFE4403 Heart Rate Monitors and Low-Cost Pulse Oximeters
3  *
4  * Copyright (C) 2015-2016 Texas Instruments Incorporated - http://www.ti.com/
5  *	Andrew F. Davis <afd@ti.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful, but
12  * WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * General Public License for more details.
15  */
16 
17 #include <linux/device.h>
18 #include <linux/err.h>
19 #include <linux/interrupt.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/regmap.h>
23 #include <linux/spi/spi.h>
24 #include <linux/sysfs.h>
25 #include <linux/regulator/consumer.h>
26 
27 #include <linux/iio/iio.h>
28 #include <linux/iio/sysfs.h>
29 #include <linux/iio/buffer.h>
30 #include <linux/iio/trigger.h>
31 #include <linux/iio/triggered_buffer.h>
32 #include <linux/iio/trigger_consumer.h>
33 
34 #include "afe440x.h"
35 
36 #define AFE4403_DRIVER_NAME		"afe4403"
37 
38 /* AFE4403 Registers */
39 #define AFE4403_TIAGAIN			0x20
40 #define AFE4403_TIA_AMB_GAIN		0x21
41 
42 enum afe4403_fields {
43 	/* Gains */
44 	F_RF_LED1, F_CF_LED1,
45 	F_RF_LED, F_CF_LED,
46 
47 	/* LED Current */
48 	F_ILED1, F_ILED2,
49 
50 	/* sentinel */
51 	F_MAX_FIELDS
52 };
53 
54 static const struct reg_field afe4403_reg_fields[] = {
55 	/* Gains */
56 	[F_RF_LED1]	= REG_FIELD(AFE4403_TIAGAIN, 0, 2),
57 	[F_CF_LED1]	= REG_FIELD(AFE4403_TIAGAIN, 3, 7),
58 	[F_RF_LED]	= REG_FIELD(AFE4403_TIA_AMB_GAIN, 0, 2),
59 	[F_CF_LED]	= REG_FIELD(AFE4403_TIA_AMB_GAIN, 3, 7),
60 	/* LED Current */
61 	[F_ILED1]	= REG_FIELD(AFE440X_LEDCNTRL, 0, 7),
62 	[F_ILED2]	= REG_FIELD(AFE440X_LEDCNTRL, 8, 15),
63 };
64 
65 /**
66  * struct afe4403_data - AFE4403 device instance data
67  * @dev: Device structure
68  * @spi: SPI device handle
69  * @regmap: Register map of the device
70  * @fields: Register fields of the device
71  * @regulator: Pointer to the regulator for the IC
72  * @trig: IIO trigger for this device
73  * @irq: ADC_RDY line interrupt number
74  */
75 struct afe4403_data {
76 	struct device *dev;
77 	struct spi_device *spi;
78 	struct regmap *regmap;
79 	struct regmap_field *fields[F_MAX_FIELDS];
80 	struct regulator *regulator;
81 	struct iio_trigger *trig;
82 	int irq;
83 };
84 
85 enum afe4403_chan_id {
86 	LED2 = 1,
87 	ALED2,
88 	LED1,
89 	ALED1,
90 	LED2_ALED2,
91 	LED1_ALED1,
92 };
93 
94 static const unsigned int afe4403_channel_values[] = {
95 	[LED2] = AFE440X_LED2VAL,
96 	[ALED2] = AFE440X_ALED2VAL,
97 	[LED1] = AFE440X_LED1VAL,
98 	[ALED1] = AFE440X_ALED1VAL,
99 	[LED2_ALED2] = AFE440X_LED2_ALED2VAL,
100 	[LED1_ALED1] = AFE440X_LED1_ALED1VAL,
101 };
102 
103 static const unsigned int afe4403_channel_leds[] = {
104 	[LED2] = F_ILED2,
105 	[LED1] = F_ILED1,
106 };
107 
108 static const struct iio_chan_spec afe4403_channels[] = {
109 	/* ADC values */
110 	AFE440X_INTENSITY_CHAN(LED2, 0),
111 	AFE440X_INTENSITY_CHAN(ALED2, 0),
112 	AFE440X_INTENSITY_CHAN(LED1, 0),
113 	AFE440X_INTENSITY_CHAN(ALED1, 0),
114 	AFE440X_INTENSITY_CHAN(LED2_ALED2, 0),
115 	AFE440X_INTENSITY_CHAN(LED1_ALED1, 0),
116 	/* LED current */
117 	AFE440X_CURRENT_CHAN(LED2),
118 	AFE440X_CURRENT_CHAN(LED1),
119 };
120 
121 static const struct afe440x_val_table afe4403_res_table[] = {
122 	{ 500000 }, { 250000 }, { 100000 }, { 50000 },
123 	{ 25000 }, { 10000 }, { 1000000 }, { 0 },
124 };
125 AFE440X_TABLE_ATTR(in_intensity_resistance_available, afe4403_res_table);
126 
127 static const struct afe440x_val_table afe4403_cap_table[] = {
128 	{ 0, 5000 }, { 0, 10000 }, { 0, 20000 }, { 0, 25000 },
129 	{ 0, 30000 }, { 0, 35000 }, { 0, 45000 }, { 0, 50000 },
130 	{ 0, 55000 }, { 0, 60000 }, { 0, 70000 }, { 0, 75000 },
131 	{ 0, 80000 }, { 0, 85000 }, { 0, 95000 }, { 0, 100000 },
132 	{ 0, 155000 }, { 0, 160000 }, { 0, 170000 }, { 0, 175000 },
133 	{ 0, 180000 }, { 0, 185000 }, { 0, 195000 }, { 0, 200000 },
134 	{ 0, 205000 }, { 0, 210000 }, { 0, 220000 }, { 0, 225000 },
135 	{ 0, 230000 }, { 0, 235000 }, { 0, 245000 }, { 0, 250000 },
136 };
137 AFE440X_TABLE_ATTR(in_intensity_capacitance_available, afe4403_cap_table);
138 
139 static ssize_t afe440x_show_register(struct device *dev,
140 				     struct device_attribute *attr,
141 				     char *buf)
142 {
143 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
144 	struct afe4403_data *afe = iio_priv(indio_dev);
145 	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
146 	unsigned int reg_val;
147 	int vals[2];
148 	int ret;
149 
150 	ret = regmap_field_read(afe->fields[afe440x_attr->field], &reg_val);
151 	if (ret)
152 		return ret;
153 
154 	if (reg_val >= afe440x_attr->table_size)
155 		return -EINVAL;
156 
157 	vals[0] = afe440x_attr->val_table[reg_val].integer;
158 	vals[1] = afe440x_attr->val_table[reg_val].fract;
159 
160 	return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, 2, vals);
161 }
162 
163 static ssize_t afe440x_store_register(struct device *dev,
164 				      struct device_attribute *attr,
165 				      const char *buf, size_t count)
166 {
167 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
168 	struct afe4403_data *afe = iio_priv(indio_dev);
169 	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
170 	int val, integer, fract, ret;
171 
172 	ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
173 	if (ret)
174 		return ret;
175 
176 	for (val = 0; val < afe440x_attr->table_size; val++)
177 		if (afe440x_attr->val_table[val].integer == integer &&
178 		    afe440x_attr->val_table[val].fract == fract)
179 			break;
180 	if (val == afe440x_attr->table_size)
181 		return -EINVAL;
182 
183 	ret = regmap_field_write(afe->fields[afe440x_attr->field], val);
184 	if (ret)
185 		return ret;
186 
187 	return count;
188 }
189 
190 static AFE440X_ATTR(in_intensity1_resistance, F_RF_LED, afe4403_res_table);
191 static AFE440X_ATTR(in_intensity1_capacitance, F_CF_LED, afe4403_cap_table);
192 
193 static AFE440X_ATTR(in_intensity2_resistance, F_RF_LED, afe4403_res_table);
194 static AFE440X_ATTR(in_intensity2_capacitance, F_CF_LED, afe4403_cap_table);
195 
196 static AFE440X_ATTR(in_intensity3_resistance, F_RF_LED1, afe4403_res_table);
197 static AFE440X_ATTR(in_intensity3_capacitance, F_CF_LED1, afe4403_cap_table);
198 
199 static AFE440X_ATTR(in_intensity4_resistance, F_RF_LED1, afe4403_res_table);
200 static AFE440X_ATTR(in_intensity4_capacitance, F_CF_LED1, afe4403_cap_table);
201 
202 static struct attribute *afe440x_attributes[] = {
203 	&dev_attr_in_intensity_resistance_available.attr,
204 	&dev_attr_in_intensity_capacitance_available.attr,
205 	&afe440x_attr_in_intensity1_resistance.dev_attr.attr,
206 	&afe440x_attr_in_intensity1_capacitance.dev_attr.attr,
207 	&afe440x_attr_in_intensity2_resistance.dev_attr.attr,
208 	&afe440x_attr_in_intensity2_capacitance.dev_attr.attr,
209 	&afe440x_attr_in_intensity3_resistance.dev_attr.attr,
210 	&afe440x_attr_in_intensity3_capacitance.dev_attr.attr,
211 	&afe440x_attr_in_intensity4_resistance.dev_attr.attr,
212 	&afe440x_attr_in_intensity4_capacitance.dev_attr.attr,
213 	NULL
214 };
215 
216 static const struct attribute_group afe440x_attribute_group = {
217 	.attrs = afe440x_attributes
218 };
219 
220 static int afe4403_read(struct afe4403_data *afe, unsigned int reg, u32 *val)
221 {
222 	u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
223 	u8 rx[3];
224 	int ret;
225 
226 	/* Enable reading from the device */
227 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
228 	if (ret)
229 		return ret;
230 
231 	ret = spi_write_then_read(afe->spi, &reg, 1, rx, 3);
232 	if (ret)
233 		return ret;
234 
235 	*val = (rx[0] << 16) |
236 		(rx[1] << 8) |
237 		(rx[2]);
238 
239 	/* Disable reading from the device */
240 	tx[3] = AFE440X_CONTROL0_WRITE;
241 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
242 	if (ret)
243 		return ret;
244 
245 	return 0;
246 }
247 
248 static int afe4403_read_raw(struct iio_dev *indio_dev,
249 			    struct iio_chan_spec const *chan,
250 			    int *val, int *val2, long mask)
251 {
252 	struct afe4403_data *afe = iio_priv(indio_dev);
253 	unsigned int reg = afe4403_channel_values[chan->address];
254 	unsigned int field = afe4403_channel_leds[chan->address];
255 	int ret;
256 
257 	switch (chan->type) {
258 	case IIO_INTENSITY:
259 		switch (mask) {
260 		case IIO_CHAN_INFO_RAW:
261 			ret = afe4403_read(afe, reg, val);
262 			if (ret)
263 				return ret;
264 			return IIO_VAL_INT;
265 		}
266 		break;
267 	case IIO_CURRENT:
268 		switch (mask) {
269 		case IIO_CHAN_INFO_RAW:
270 			ret = regmap_field_read(afe->fields[field], val);
271 			if (ret)
272 				return ret;
273 			return IIO_VAL_INT;
274 		case IIO_CHAN_INFO_SCALE:
275 			*val = 0;
276 			*val2 = 800000;
277 			return IIO_VAL_INT_PLUS_MICRO;
278 		}
279 		break;
280 	default:
281 		break;
282 	}
283 
284 	return -EINVAL;
285 }
286 
287 static int afe4403_write_raw(struct iio_dev *indio_dev,
288 			     struct iio_chan_spec const *chan,
289 			     int val, int val2, long mask)
290 {
291 	struct afe4403_data *afe = iio_priv(indio_dev);
292 	unsigned int field = afe4403_channel_leds[chan->address];
293 
294 	switch (chan->type) {
295 	case IIO_CURRENT:
296 		switch (mask) {
297 		case IIO_CHAN_INFO_RAW:
298 			return regmap_field_write(afe->fields[field], val);
299 		}
300 		break;
301 	default:
302 		break;
303 	}
304 
305 	return -EINVAL;
306 }
307 
308 static const struct iio_info afe4403_iio_info = {
309 	.attrs = &afe440x_attribute_group,
310 	.read_raw = afe4403_read_raw,
311 	.write_raw = afe4403_write_raw,
312 	.driver_module = THIS_MODULE,
313 };
314 
315 static irqreturn_t afe4403_trigger_handler(int irq, void *private)
316 {
317 	struct iio_poll_func *pf = private;
318 	struct iio_dev *indio_dev = pf->indio_dev;
319 	struct afe4403_data *afe = iio_priv(indio_dev);
320 	int ret, bit, i = 0;
321 	s32 buffer[8];
322 	u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
323 	u8 rx[3];
324 
325 	/* Enable reading from the device */
326 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
327 	if (ret)
328 		goto err;
329 
330 	for_each_set_bit(bit, indio_dev->active_scan_mask,
331 			 indio_dev->masklength) {
332 		ret = spi_write_then_read(afe->spi,
333 					  &afe4403_channel_values[bit], 1,
334 					  rx, 3);
335 		if (ret)
336 			goto err;
337 
338 		buffer[i++] = (rx[0] << 16) |
339 				(rx[1] << 8) |
340 				(rx[2]);
341 	}
342 
343 	/* Disable reading from the device */
344 	tx[3] = AFE440X_CONTROL0_WRITE;
345 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
346 	if (ret)
347 		goto err;
348 
349 	iio_push_to_buffers_with_timestamp(indio_dev, buffer, pf->timestamp);
350 err:
351 	iio_trigger_notify_done(indio_dev->trig);
352 
353 	return IRQ_HANDLED;
354 }
355 
356 static const struct iio_trigger_ops afe4403_trigger_ops = {
357 	.owner = THIS_MODULE,
358 };
359 
360 #define AFE4403_TIMING_PAIRS			\
361 	{ AFE440X_LED2STC,	0x000050 },	\
362 	{ AFE440X_LED2ENDC,	0x0003e7 },	\
363 	{ AFE440X_LED1LEDSTC,	0x0007d0 },	\
364 	{ AFE440X_LED1LEDENDC,	0x000bb7 },	\
365 	{ AFE440X_ALED2STC,	0x000438 },	\
366 	{ AFE440X_ALED2ENDC,	0x0007cf },	\
367 	{ AFE440X_LED1STC,	0x000820 },	\
368 	{ AFE440X_LED1ENDC,	0x000bb7 },	\
369 	{ AFE440X_LED2LEDSTC,	0x000000 },	\
370 	{ AFE440X_LED2LEDENDC,	0x0003e7 },	\
371 	{ AFE440X_ALED1STC,	0x000c08 },	\
372 	{ AFE440X_ALED1ENDC,	0x000f9f },	\
373 	{ AFE440X_LED2CONVST,	0x0003ef },	\
374 	{ AFE440X_LED2CONVEND,	0x0007cf },	\
375 	{ AFE440X_ALED2CONVST,	0x0007d7 },	\
376 	{ AFE440X_ALED2CONVEND,	0x000bb7 },	\
377 	{ AFE440X_LED1CONVST,	0x000bbf },	\
378 	{ AFE440X_LED1CONVEND,	0x009c3f },	\
379 	{ AFE440X_ALED1CONVST,	0x000fa7 },	\
380 	{ AFE440X_ALED1CONVEND,	0x001387 },	\
381 	{ AFE440X_ADCRSTSTCT0,	0x0003e8 },	\
382 	{ AFE440X_ADCRSTENDCT0,	0x0003eb },	\
383 	{ AFE440X_ADCRSTSTCT1,	0x0007d0 },	\
384 	{ AFE440X_ADCRSTENDCT1,	0x0007d3 },	\
385 	{ AFE440X_ADCRSTSTCT2,	0x000bb8 },	\
386 	{ AFE440X_ADCRSTENDCT2,	0x000bbb },	\
387 	{ AFE440X_ADCRSTSTCT3,	0x000fa0 },	\
388 	{ AFE440X_ADCRSTENDCT3,	0x000fa3 },	\
389 	{ AFE440X_PRPCOUNT,	0x009c3f },	\
390 	{ AFE440X_PDNCYCLESTC,	0x001518 },	\
391 	{ AFE440X_PDNCYCLEENDC,	0x00991f }
392 
393 static const struct reg_sequence afe4403_reg_sequences[] = {
394 	AFE4403_TIMING_PAIRS,
395 	{ AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN },
396 	{ AFE4403_TIAGAIN, AFE440X_TIAGAIN_ENSEPGAIN },
397 };
398 
399 static const struct regmap_range afe4403_yes_ranges[] = {
400 	regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL),
401 };
402 
403 static const struct regmap_access_table afe4403_volatile_table = {
404 	.yes_ranges = afe4403_yes_ranges,
405 	.n_yes_ranges = ARRAY_SIZE(afe4403_yes_ranges),
406 };
407 
408 static const struct regmap_config afe4403_regmap_config = {
409 	.reg_bits = 8,
410 	.val_bits = 24,
411 
412 	.max_register = AFE440X_PDNCYCLEENDC,
413 	.cache_type = REGCACHE_RBTREE,
414 	.volatile_table = &afe4403_volatile_table,
415 };
416 
417 static const struct of_device_id afe4403_of_match[] = {
418 	{ .compatible = "ti,afe4403", },
419 	{ /* sentinel */ }
420 };
421 MODULE_DEVICE_TABLE(of, afe4403_of_match);
422 
423 static int __maybe_unused afe4403_suspend(struct device *dev)
424 {
425 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
426 	struct afe4403_data *afe = iio_priv(indio_dev);
427 	int ret;
428 
429 	ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
430 				 AFE440X_CONTROL2_PDN_AFE,
431 				 AFE440X_CONTROL2_PDN_AFE);
432 	if (ret)
433 		return ret;
434 
435 	ret = regulator_disable(afe->regulator);
436 	if (ret) {
437 		dev_err(dev, "Unable to disable regulator\n");
438 		return ret;
439 	}
440 
441 	return 0;
442 }
443 
444 static int __maybe_unused afe4403_resume(struct device *dev)
445 {
446 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
447 	struct afe4403_data *afe = iio_priv(indio_dev);
448 	int ret;
449 
450 	ret = regulator_enable(afe->regulator);
451 	if (ret) {
452 		dev_err(dev, "Unable to enable regulator\n");
453 		return ret;
454 	}
455 
456 	ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
457 				 AFE440X_CONTROL2_PDN_AFE, 0);
458 	if (ret)
459 		return ret;
460 
461 	return 0;
462 }
463 
464 static SIMPLE_DEV_PM_OPS(afe4403_pm_ops, afe4403_suspend, afe4403_resume);
465 
466 static int afe4403_probe(struct spi_device *spi)
467 {
468 	struct iio_dev *indio_dev;
469 	struct afe4403_data *afe;
470 	int i, ret;
471 
472 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*afe));
473 	if (!indio_dev)
474 		return -ENOMEM;
475 
476 	afe = iio_priv(indio_dev);
477 	spi_set_drvdata(spi, indio_dev);
478 
479 	afe->dev = &spi->dev;
480 	afe->spi = spi;
481 	afe->irq = spi->irq;
482 
483 	afe->regmap = devm_regmap_init_spi(spi, &afe4403_regmap_config);
484 	if (IS_ERR(afe->regmap)) {
485 		dev_err(afe->dev, "Unable to allocate register map\n");
486 		return PTR_ERR(afe->regmap);
487 	}
488 
489 	for (i = 0; i < F_MAX_FIELDS; i++) {
490 		afe->fields[i] = devm_regmap_field_alloc(afe->dev, afe->regmap,
491 							 afe4403_reg_fields[i]);
492 		if (IS_ERR(afe->fields[i])) {
493 			dev_err(afe->dev, "Unable to allocate regmap fields\n");
494 			return PTR_ERR(afe->fields[i]);
495 		}
496 	}
497 
498 	afe->regulator = devm_regulator_get(afe->dev, "tx_sup");
499 	if (IS_ERR(afe->regulator)) {
500 		dev_err(afe->dev, "Unable to get regulator\n");
501 		return PTR_ERR(afe->regulator);
502 	}
503 	ret = regulator_enable(afe->regulator);
504 	if (ret) {
505 		dev_err(afe->dev, "Unable to enable regulator\n");
506 		return ret;
507 	}
508 
509 	ret = regmap_write(afe->regmap, AFE440X_CONTROL0,
510 			   AFE440X_CONTROL0_SW_RESET);
511 	if (ret) {
512 		dev_err(afe->dev, "Unable to reset device\n");
513 		goto err_disable_reg;
514 	}
515 
516 	ret = regmap_multi_reg_write(afe->regmap, afe4403_reg_sequences,
517 				     ARRAY_SIZE(afe4403_reg_sequences));
518 	if (ret) {
519 		dev_err(afe->dev, "Unable to set register defaults\n");
520 		goto err_disable_reg;
521 	}
522 
523 	indio_dev->modes = INDIO_DIRECT_MODE;
524 	indio_dev->dev.parent = afe->dev;
525 	indio_dev->channels = afe4403_channels;
526 	indio_dev->num_channels = ARRAY_SIZE(afe4403_channels);
527 	indio_dev->name = AFE4403_DRIVER_NAME;
528 	indio_dev->info = &afe4403_iio_info;
529 
530 	if (afe->irq > 0) {
531 		afe->trig = devm_iio_trigger_alloc(afe->dev,
532 						   "%s-dev%d",
533 						   indio_dev->name,
534 						   indio_dev->id);
535 		if (!afe->trig) {
536 			dev_err(afe->dev, "Unable to allocate IIO trigger\n");
537 			ret = -ENOMEM;
538 			goto err_disable_reg;
539 		}
540 
541 		iio_trigger_set_drvdata(afe->trig, indio_dev);
542 
543 		afe->trig->ops = &afe4403_trigger_ops;
544 		afe->trig->dev.parent = afe->dev;
545 
546 		ret = iio_trigger_register(afe->trig);
547 		if (ret) {
548 			dev_err(afe->dev, "Unable to register IIO trigger\n");
549 			goto err_disable_reg;
550 		}
551 
552 		ret = devm_request_threaded_irq(afe->dev, afe->irq,
553 						iio_trigger_generic_data_rdy_poll,
554 						NULL, IRQF_ONESHOT,
555 						AFE4403_DRIVER_NAME,
556 						afe->trig);
557 		if (ret) {
558 			dev_err(afe->dev, "Unable to request IRQ\n");
559 			goto err_trig;
560 		}
561 	}
562 
563 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
564 					 afe4403_trigger_handler, NULL);
565 	if (ret) {
566 		dev_err(afe->dev, "Unable to setup buffer\n");
567 		goto err_trig;
568 	}
569 
570 	ret = iio_device_register(indio_dev);
571 	if (ret) {
572 		dev_err(afe->dev, "Unable to register IIO device\n");
573 		goto err_buff;
574 	}
575 
576 	return 0;
577 
578 err_buff:
579 	iio_triggered_buffer_cleanup(indio_dev);
580 err_trig:
581 	if (afe->irq > 0)
582 		iio_trigger_unregister(afe->trig);
583 err_disable_reg:
584 	regulator_disable(afe->regulator);
585 
586 	return ret;
587 }
588 
589 static int afe4403_remove(struct spi_device *spi)
590 {
591 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
592 	struct afe4403_data *afe = iio_priv(indio_dev);
593 	int ret;
594 
595 	iio_device_unregister(indio_dev);
596 
597 	iio_triggered_buffer_cleanup(indio_dev);
598 
599 	if (afe->irq > 0)
600 		iio_trigger_unregister(afe->trig);
601 
602 	ret = regulator_disable(afe->regulator);
603 	if (ret) {
604 		dev_err(afe->dev, "Unable to disable regulator\n");
605 		return ret;
606 	}
607 
608 	return 0;
609 }
610 
611 static const struct spi_device_id afe4403_ids[] = {
612 	{ "afe4403", 0 },
613 	{ /* sentinel */ }
614 };
615 MODULE_DEVICE_TABLE(spi, afe4403_ids);
616 
617 static struct spi_driver afe4403_spi_driver = {
618 	.driver = {
619 		.name = AFE4403_DRIVER_NAME,
620 		.of_match_table = afe4403_of_match,
621 		.pm = &afe4403_pm_ops,
622 	},
623 	.probe = afe4403_probe,
624 	.remove = afe4403_remove,
625 	.id_table = afe4403_ids,
626 };
627 module_spi_driver(afe4403_spi_driver);
628 
629 MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
630 MODULE_DESCRIPTION("TI AFE4403 Heart Rate Monitor and Pulse Oximeter AFE");
631 MODULE_LICENSE("GPL v2");
632