xref: /openbmc/linux/drivers/iio/health/afe4403.c (revision 58143c1e)
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 - https://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 <asm/unaligned.h>
27 
28 #include "afe440x.h"
29 
30 #define AFE4403_DRIVER_NAME		"afe4403"
31 
32 /* AFE4403 Registers */
33 #define AFE4403_TIAGAIN			0x20
34 #define AFE4403_TIA_AMB_GAIN		0x21
35 
36 enum afe4403_fields {
37 	/* Gains */
38 	F_RF_LED1, F_CF_LED1,
39 	F_RF_LED, F_CF_LED,
40 
41 	/* LED Current */
42 	F_ILED1, F_ILED2,
43 
44 	/* sentinel */
45 	F_MAX_FIELDS
46 };
47 
48 static const struct reg_field afe4403_reg_fields[] = {
49 	/* Gains */
50 	[F_RF_LED1]	= REG_FIELD(AFE4403_TIAGAIN, 0, 2),
51 	[F_CF_LED1]	= REG_FIELD(AFE4403_TIAGAIN, 3, 7),
52 	[F_RF_LED]	= REG_FIELD(AFE4403_TIA_AMB_GAIN, 0, 2),
53 	[F_CF_LED]	= REG_FIELD(AFE4403_TIA_AMB_GAIN, 3, 7),
54 	/* LED Current */
55 	[F_ILED1]	= REG_FIELD(AFE440X_LEDCNTRL, 0, 7),
56 	[F_ILED2]	= REG_FIELD(AFE440X_LEDCNTRL, 8, 15),
57 };
58 
59 /**
60  * struct afe4403_data - AFE4403 device instance data
61  * @dev: Device structure
62  * @spi: SPI device handle
63  * @regmap: Register map of the device
64  * @fields: Register fields of the device
65  * @regulator: Pointer to the regulator for the IC
66  * @trig: IIO trigger for this device
67  * @irq: ADC_RDY line interrupt number
68  * @buffer: Used to construct data layout to push into IIO buffer.
69  */
70 struct afe4403_data {
71 	struct device *dev;
72 	struct spi_device *spi;
73 	struct regmap *regmap;
74 	struct regmap_field *fields[F_MAX_FIELDS];
75 	struct regulator *regulator;
76 	struct iio_trigger *trig;
77 	int irq;
78 	/* Ensure suitable alignment for timestamp */
79 	s32 buffer[8] __aligned(8);
80 };
81 
82 enum afe4403_chan_id {
83 	LED2 = 1,
84 	ALED2,
85 	LED1,
86 	ALED1,
87 	LED2_ALED2,
88 	LED1_ALED1,
89 };
90 
91 static const unsigned int afe4403_channel_values[] = {
92 	[LED2] = AFE440X_LED2VAL,
93 	[ALED2] = AFE440X_ALED2VAL,
94 	[LED1] = AFE440X_LED1VAL,
95 	[ALED1] = AFE440X_ALED1VAL,
96 	[LED2_ALED2] = AFE440X_LED2_ALED2VAL,
97 	[LED1_ALED1] = AFE440X_LED1_ALED1VAL,
98 };
99 
100 static const unsigned int afe4403_channel_leds[] = {
101 	[LED2] = F_ILED2,
102 	[LED1] = F_ILED1,
103 };
104 
105 static const struct iio_chan_spec afe4403_channels[] = {
106 	/* ADC values */
107 	AFE440X_INTENSITY_CHAN(LED2, 0),
108 	AFE440X_INTENSITY_CHAN(ALED2, 0),
109 	AFE440X_INTENSITY_CHAN(LED1, 0),
110 	AFE440X_INTENSITY_CHAN(ALED1, 0),
111 	AFE440X_INTENSITY_CHAN(LED2_ALED2, 0),
112 	AFE440X_INTENSITY_CHAN(LED1_ALED1, 0),
113 	/* LED current */
114 	AFE440X_CURRENT_CHAN(LED2),
115 	AFE440X_CURRENT_CHAN(LED1),
116 };
117 
118 static const struct afe440x_val_table afe4403_res_table[] = {
119 	{ 500000 }, { 250000 }, { 100000 }, { 50000 },
120 	{ 25000 }, { 10000 }, { 1000000 }, { 0 },
121 };
122 AFE440X_TABLE_ATTR(in_intensity_resistance_available, afe4403_res_table);
123 
124 static const struct afe440x_val_table afe4403_cap_table[] = {
125 	{ 0, 5000 }, { 0, 10000 }, { 0, 20000 }, { 0, 25000 },
126 	{ 0, 30000 }, { 0, 35000 }, { 0, 45000 }, { 0, 50000 },
127 	{ 0, 55000 }, { 0, 60000 }, { 0, 70000 }, { 0, 75000 },
128 	{ 0, 80000 }, { 0, 85000 }, { 0, 95000 }, { 0, 100000 },
129 	{ 0, 155000 }, { 0, 160000 }, { 0, 170000 }, { 0, 175000 },
130 	{ 0, 180000 }, { 0, 185000 }, { 0, 195000 }, { 0, 200000 },
131 	{ 0, 205000 }, { 0, 210000 }, { 0, 220000 }, { 0, 225000 },
132 	{ 0, 230000 }, { 0, 235000 }, { 0, 245000 }, { 0, 250000 },
133 };
134 AFE440X_TABLE_ATTR(in_intensity_capacitance_available, afe4403_cap_table);
135 
afe440x_show_register(struct device * dev,struct device_attribute * attr,char * buf)136 static ssize_t afe440x_show_register(struct device *dev,
137 				     struct device_attribute *attr,
138 				     char *buf)
139 {
140 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
141 	struct afe4403_data *afe = iio_priv(indio_dev);
142 	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
143 	unsigned int reg_val;
144 	int vals[2];
145 	int ret;
146 
147 	ret = regmap_field_read(afe->fields[afe440x_attr->field], &reg_val);
148 	if (ret)
149 		return ret;
150 
151 	if (reg_val >= afe440x_attr->table_size)
152 		return -EINVAL;
153 
154 	vals[0] = afe440x_attr->val_table[reg_val].integer;
155 	vals[1] = afe440x_attr->val_table[reg_val].fract;
156 
157 	return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, 2, vals);
158 }
159 
afe440x_store_register(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)160 static ssize_t afe440x_store_register(struct device *dev,
161 				      struct device_attribute *attr,
162 				      const char *buf, size_t count)
163 {
164 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
165 	struct afe4403_data *afe = iio_priv(indio_dev);
166 	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
167 	int val, integer, fract, ret;
168 
169 	ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
170 	if (ret)
171 		return ret;
172 
173 	for (val = 0; val < afe440x_attr->table_size; val++)
174 		if (afe440x_attr->val_table[val].integer == integer &&
175 		    afe440x_attr->val_table[val].fract == fract)
176 			break;
177 	if (val == afe440x_attr->table_size)
178 		return -EINVAL;
179 
180 	ret = regmap_field_write(afe->fields[afe440x_attr->field], val);
181 	if (ret)
182 		return ret;
183 
184 	return count;
185 }
186 
187 static AFE440X_ATTR(in_intensity1_resistance, F_RF_LED, afe4403_res_table);
188 static AFE440X_ATTR(in_intensity1_capacitance, F_CF_LED, afe4403_cap_table);
189 
190 static AFE440X_ATTR(in_intensity2_resistance, F_RF_LED, afe4403_res_table);
191 static AFE440X_ATTR(in_intensity2_capacitance, F_CF_LED, afe4403_cap_table);
192 
193 static AFE440X_ATTR(in_intensity3_resistance, F_RF_LED1, afe4403_res_table);
194 static AFE440X_ATTR(in_intensity3_capacitance, F_CF_LED1, afe4403_cap_table);
195 
196 static AFE440X_ATTR(in_intensity4_resistance, F_RF_LED1, afe4403_res_table);
197 static AFE440X_ATTR(in_intensity4_capacitance, F_CF_LED1, afe4403_cap_table);
198 
199 static struct attribute *afe440x_attributes[] = {
200 	&dev_attr_in_intensity_resistance_available.attr,
201 	&dev_attr_in_intensity_capacitance_available.attr,
202 	&afe440x_attr_in_intensity1_resistance.dev_attr.attr,
203 	&afe440x_attr_in_intensity1_capacitance.dev_attr.attr,
204 	&afe440x_attr_in_intensity2_resistance.dev_attr.attr,
205 	&afe440x_attr_in_intensity2_capacitance.dev_attr.attr,
206 	&afe440x_attr_in_intensity3_resistance.dev_attr.attr,
207 	&afe440x_attr_in_intensity3_capacitance.dev_attr.attr,
208 	&afe440x_attr_in_intensity4_resistance.dev_attr.attr,
209 	&afe440x_attr_in_intensity4_capacitance.dev_attr.attr,
210 	NULL
211 };
212 
213 static const struct attribute_group afe440x_attribute_group = {
214 	.attrs = afe440x_attributes
215 };
216 
afe4403_read(struct afe4403_data * afe,unsigned int reg,u32 * val)217 static int afe4403_read(struct afe4403_data *afe, unsigned int reg, u32 *val)
218 {
219 	u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
220 	u8 rx[3];
221 	int ret;
222 
223 	/* Enable reading from the device */
224 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
225 	if (ret)
226 		return ret;
227 
228 	ret = spi_write_then_read(afe->spi, &reg, 1, rx, sizeof(rx));
229 	if (ret)
230 		return ret;
231 
232 	*val = get_unaligned_be24(&rx[0]);
233 
234 	/* Disable reading from the device */
235 	tx[3] = AFE440X_CONTROL0_WRITE;
236 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
237 	if (ret)
238 		return ret;
239 
240 	return 0;
241 }
242 
afe4403_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)243 static int afe4403_read_raw(struct iio_dev *indio_dev,
244 			    struct iio_chan_spec const *chan,
245 			    int *val, int *val2, long mask)
246 {
247 	struct afe4403_data *afe = iio_priv(indio_dev);
248 	unsigned int reg, field;
249 	int ret;
250 
251 	switch (chan->type) {
252 	case IIO_INTENSITY:
253 		switch (mask) {
254 		case IIO_CHAN_INFO_RAW:
255 			reg = afe4403_channel_values[chan->address];
256 			ret = afe4403_read(afe, reg, val);
257 			if (ret)
258 				return ret;
259 			return IIO_VAL_INT;
260 		}
261 		break;
262 	case IIO_CURRENT:
263 		switch (mask) {
264 		case IIO_CHAN_INFO_RAW:
265 			field = afe4403_channel_leds[chan->address];
266 			ret = regmap_field_read(afe->fields[field], val);
267 			if (ret)
268 				return ret;
269 			return IIO_VAL_INT;
270 		case IIO_CHAN_INFO_SCALE:
271 			*val = 0;
272 			*val2 = 800000;
273 			return IIO_VAL_INT_PLUS_MICRO;
274 		}
275 		break;
276 	default:
277 		break;
278 	}
279 
280 	return -EINVAL;
281 }
282 
afe4403_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)283 static int afe4403_write_raw(struct iio_dev *indio_dev,
284 			     struct iio_chan_spec const *chan,
285 			     int val, int val2, long mask)
286 {
287 	struct afe4403_data *afe = iio_priv(indio_dev);
288 	unsigned int field = afe4403_channel_leds[chan->address];
289 
290 	switch (chan->type) {
291 	case IIO_CURRENT:
292 		switch (mask) {
293 		case IIO_CHAN_INFO_RAW:
294 			return regmap_field_write(afe->fields[field], val);
295 		}
296 		break;
297 	default:
298 		break;
299 	}
300 
301 	return -EINVAL;
302 }
303 
304 static const struct iio_info afe4403_iio_info = {
305 	.attrs = &afe440x_attribute_group,
306 	.read_raw = afe4403_read_raw,
307 	.write_raw = afe4403_write_raw,
308 };
309 
afe4403_trigger_handler(int irq,void * private)310 static irqreturn_t afe4403_trigger_handler(int irq, void *private)
311 {
312 	struct iio_poll_func *pf = private;
313 	struct iio_dev *indio_dev = pf->indio_dev;
314 	struct afe4403_data *afe = iio_priv(indio_dev);
315 	int ret, bit, i = 0;
316 	u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
317 	u8 rx[3];
318 
319 	/* Enable reading from the device */
320 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
321 	if (ret)
322 		goto err;
323 
324 	for_each_set_bit(bit, indio_dev->active_scan_mask,
325 			 indio_dev->masklength) {
326 		ret = spi_write_then_read(afe->spi,
327 					  &afe4403_channel_values[bit], 1,
328 					  rx, sizeof(rx));
329 		if (ret)
330 			goto err;
331 
332 		afe->buffer[i++] = get_unaligned_be24(&rx[0]);
333 	}
334 
335 	/* Disable reading from the device */
336 	tx[3] = AFE440X_CONTROL0_WRITE;
337 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
338 	if (ret)
339 		goto err;
340 
341 	iio_push_to_buffers_with_timestamp(indio_dev, afe->buffer,
342 					   pf->timestamp);
343 err:
344 	iio_trigger_notify_done(indio_dev->trig);
345 
346 	return IRQ_HANDLED;
347 }
348 
349 #define AFE4403_TIMING_PAIRS			\
350 	{ AFE440X_LED2STC,	0x000050 },	\
351 	{ AFE440X_LED2ENDC,	0x0003e7 },	\
352 	{ AFE440X_LED1LEDSTC,	0x0007d0 },	\
353 	{ AFE440X_LED1LEDENDC,	0x000bb7 },	\
354 	{ AFE440X_ALED2STC,	0x000438 },	\
355 	{ AFE440X_ALED2ENDC,	0x0007cf },	\
356 	{ AFE440X_LED1STC,	0x000820 },	\
357 	{ AFE440X_LED1ENDC,	0x000bb7 },	\
358 	{ AFE440X_LED2LEDSTC,	0x000000 },	\
359 	{ AFE440X_LED2LEDENDC,	0x0003e7 },	\
360 	{ AFE440X_ALED1STC,	0x000c08 },	\
361 	{ AFE440X_ALED1ENDC,	0x000f9f },	\
362 	{ AFE440X_LED2CONVST,	0x0003ef },	\
363 	{ AFE440X_LED2CONVEND,	0x0007cf },	\
364 	{ AFE440X_ALED2CONVST,	0x0007d7 },	\
365 	{ AFE440X_ALED2CONVEND,	0x000bb7 },	\
366 	{ AFE440X_LED1CONVST,	0x000bbf },	\
367 	{ AFE440X_LED1CONVEND,	0x009c3f },	\
368 	{ AFE440X_ALED1CONVST,	0x000fa7 },	\
369 	{ AFE440X_ALED1CONVEND,	0x001387 },	\
370 	{ AFE440X_ADCRSTSTCT0,	0x0003e8 },	\
371 	{ AFE440X_ADCRSTENDCT0,	0x0003eb },	\
372 	{ AFE440X_ADCRSTSTCT1,	0x0007d0 },	\
373 	{ AFE440X_ADCRSTENDCT1,	0x0007d3 },	\
374 	{ AFE440X_ADCRSTSTCT2,	0x000bb8 },	\
375 	{ AFE440X_ADCRSTENDCT2,	0x000bbb },	\
376 	{ AFE440X_ADCRSTSTCT3,	0x000fa0 },	\
377 	{ AFE440X_ADCRSTENDCT3,	0x000fa3 },	\
378 	{ AFE440X_PRPCOUNT,	0x009c3f },	\
379 	{ AFE440X_PDNCYCLESTC,	0x001518 },	\
380 	{ AFE440X_PDNCYCLEENDC,	0x00991f }
381 
382 static const struct reg_sequence afe4403_reg_sequences[] = {
383 	AFE4403_TIMING_PAIRS,
384 	{ AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN },
385 	{ AFE4403_TIAGAIN, AFE440X_TIAGAIN_ENSEPGAIN },
386 };
387 
388 static const struct regmap_range afe4403_yes_ranges[] = {
389 	regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL),
390 };
391 
392 static const struct regmap_access_table afe4403_volatile_table = {
393 	.yes_ranges = afe4403_yes_ranges,
394 	.n_yes_ranges = ARRAY_SIZE(afe4403_yes_ranges),
395 };
396 
397 static const struct regmap_config afe4403_regmap_config = {
398 	.reg_bits = 8,
399 	.val_bits = 24,
400 
401 	.max_register = AFE440X_PDNCYCLEENDC,
402 	.cache_type = REGCACHE_RBTREE,
403 	.volatile_table = &afe4403_volatile_table,
404 };
405 
406 static const struct of_device_id afe4403_of_match[] = {
407 	{ .compatible = "ti,afe4403", },
408 	{ /* sentinel */ }
409 };
410 MODULE_DEVICE_TABLE(of, afe4403_of_match);
411 
afe4403_suspend(struct device * dev)412 static int afe4403_suspend(struct device *dev)
413 {
414 	struct iio_dev *indio_dev = spi_get_drvdata(to_spi_device(dev));
415 	struct afe4403_data *afe = iio_priv(indio_dev);
416 	int ret;
417 
418 	ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
419 				 AFE440X_CONTROL2_PDN_AFE,
420 				 AFE440X_CONTROL2_PDN_AFE);
421 	if (ret)
422 		return ret;
423 
424 	ret = regulator_disable(afe->regulator);
425 	if (ret) {
426 		dev_err(dev, "Unable to disable regulator\n");
427 		return ret;
428 	}
429 
430 	return 0;
431 }
432 
afe4403_resume(struct device * dev)433 static int afe4403_resume(struct device *dev)
434 {
435 	struct iio_dev *indio_dev = spi_get_drvdata(to_spi_device(dev));
436 	struct afe4403_data *afe = iio_priv(indio_dev);
437 	int ret;
438 
439 	ret = regulator_enable(afe->regulator);
440 	if (ret) {
441 		dev_err(dev, "Unable to enable regulator\n");
442 		return ret;
443 	}
444 
445 	ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
446 				 AFE440X_CONTROL2_PDN_AFE, 0);
447 	if (ret)
448 		return ret;
449 
450 	return 0;
451 }
452 
453 static DEFINE_SIMPLE_DEV_PM_OPS(afe4403_pm_ops, afe4403_suspend,
454 				afe4403_resume);
455 
afe4403_probe(struct spi_device * spi)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 		return dev_err_probe(afe->dev, PTR_ERR(afe->regulator),
491 				     "Unable to get regulator\n");
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->channels = afe4403_channels;
515 	indio_dev->num_channels = ARRAY_SIZE(afe4403_channels);
516 	indio_dev->name = AFE4403_DRIVER_NAME;
517 	indio_dev->info = &afe4403_iio_info;
518 
519 	if (afe->irq > 0) {
520 		afe->trig = devm_iio_trigger_alloc(afe->dev,
521 						   "%s-dev%d",
522 						   indio_dev->name,
523 						   iio_device_id(indio_dev));
524 		if (!afe->trig) {
525 			dev_err(afe->dev, "Unable to allocate IIO trigger\n");
526 			ret = -ENOMEM;
527 			goto err_disable_reg;
528 		}
529 
530 		iio_trigger_set_drvdata(afe->trig, indio_dev);
531 
532 		ret = iio_trigger_register(afe->trig);
533 		if (ret) {
534 			dev_err(afe->dev, "Unable to register IIO trigger\n");
535 			goto err_disable_reg;
536 		}
537 
538 		ret = devm_request_threaded_irq(afe->dev, afe->irq,
539 						iio_trigger_generic_data_rdy_poll,
540 						NULL, IRQF_ONESHOT,
541 						AFE4403_DRIVER_NAME,
542 						afe->trig);
543 		if (ret) {
544 			dev_err(afe->dev, "Unable to request IRQ\n");
545 			goto err_trig;
546 		}
547 	}
548 
549 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
550 					 afe4403_trigger_handler, NULL);
551 	if (ret) {
552 		dev_err(afe->dev, "Unable to setup buffer\n");
553 		goto err_trig;
554 	}
555 
556 	ret = iio_device_register(indio_dev);
557 	if (ret) {
558 		dev_err(afe->dev, "Unable to register IIO device\n");
559 		goto err_buff;
560 	}
561 
562 	return 0;
563 
564 err_buff:
565 	iio_triggered_buffer_cleanup(indio_dev);
566 err_trig:
567 	if (afe->irq > 0)
568 		iio_trigger_unregister(afe->trig);
569 err_disable_reg:
570 	regulator_disable(afe->regulator);
571 
572 	return ret;
573 }
574 
afe4403_remove(struct spi_device * spi)575 static void afe4403_remove(struct spi_device *spi)
576 {
577 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
578 	struct afe4403_data *afe = iio_priv(indio_dev);
579 	int ret;
580 
581 	iio_device_unregister(indio_dev);
582 
583 	iio_triggered_buffer_cleanup(indio_dev);
584 
585 	if (afe->irq > 0)
586 		iio_trigger_unregister(afe->trig);
587 
588 	ret = regulator_disable(afe->regulator);
589 	if (ret)
590 		dev_warn(afe->dev, "Unable to disable regulator\n");
591 }
592 
593 static const struct spi_device_id afe4403_ids[] = {
594 	{ "afe4403", 0 },
595 	{ /* sentinel */ }
596 };
597 MODULE_DEVICE_TABLE(spi, afe4403_ids);
598 
599 static struct spi_driver afe4403_spi_driver = {
600 	.driver = {
601 		.name = AFE4403_DRIVER_NAME,
602 		.of_match_table = afe4403_of_match,
603 		.pm = pm_sleep_ptr(&afe4403_pm_ops),
604 	},
605 	.probe = afe4403_probe,
606 	.remove = afe4403_remove,
607 	.id_table = afe4403_ids,
608 };
609 module_spi_driver(afe4403_spi_driver);
610 
611 MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
612 MODULE_DESCRIPTION("TI AFE4403 Heart Rate Monitor and Pulse Oximeter AFE");
613 MODULE_LICENSE("GPL v2");
614