summaryrefslogtreecommitdiff
path: root/drivers/iio/health/afe4404.c
blob: aa9311e1e655769bc676b3d99c7e6e3630672e0a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
// SPDX-License-Identifier: GPL-2.0-only
/*
 * AFE4404 Heart Rate Monitors and Low-Cost Pulse Oximeters
 *
 * Copyright (C) 2015-2016 Texas Instruments Incorporated - https://www.ti.com/
 *	Andrew F. Davis <afd@ti.com>
 */

#include <linux/device.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/sysfs.h>
#include <linux/regulator/consumer.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/buffer.h>
#include <linux/iio/trigger.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/trigger_consumer.h>

#include "afe440x.h"

#define AFE4404_DRIVER_NAME		"afe4404"

/* AFE4404 registers */
#define AFE4404_TIA_GAIN_SEP		0x20
#define AFE4404_TIA_GAIN		0x21
#define AFE4404_PROG_TG_STC		0x34
#define AFE4404_PROG_TG_ENDC		0x35
#define AFE4404_LED3LEDSTC		0x36
#define AFE4404_LED3LEDENDC		0x37
#define AFE4404_CLKDIV_PRF		0x39
#define AFE4404_OFFDAC			0x3a
#define AFE4404_DEC			0x3d
#define AFE4404_AVG_LED2_ALED2VAL	0x3f
#define AFE4404_AVG_LED1_ALED1VAL	0x40

/* AFE4404 CONTROL2 register fields */
#define AFE440X_CONTROL2_OSC_ENABLE	BIT(9)

enum afe4404_fields {
	/* Gains */
	F_TIA_GAIN_SEP, F_TIA_CF_SEP,
	F_TIA_GAIN, TIA_CF,

	/* LED Current */
	F_ILED1, F_ILED2, F_ILED3,

	/* Offset DAC */
	F_OFFDAC_AMB2, F_OFFDAC_LED1, F_OFFDAC_AMB1, F_OFFDAC_LED2,

	/* sentinel */
	F_MAX_FIELDS
};

static const struct reg_field afe4404_reg_fields[] = {
	/* Gains */
	[F_TIA_GAIN_SEP]	= REG_FIELD(AFE4404_TIA_GAIN_SEP, 0, 2),
	[F_TIA_CF_SEP]		= REG_FIELD(AFE4404_TIA_GAIN_SEP, 3, 5),
	[F_TIA_GAIN]		= REG_FIELD(AFE4404_TIA_GAIN, 0, 2),
	[TIA_CF]		= REG_FIELD(AFE4404_TIA_GAIN, 3, 5),
	/* LED Current */
	[F_ILED1]		= REG_FIELD(AFE440X_LEDCNTRL, 0, 5),
	[F_ILED2]		= REG_FIELD(AFE440X_LEDCNTRL, 6, 11),
	[F_ILED3]		= REG_FIELD(AFE440X_LEDCNTRL, 12, 17),
	/* Offset DAC */
	[F_OFFDAC_AMB2]		= REG_FIELD(AFE4404_OFFDAC, 0, 4),
	[F_OFFDAC_LED1]		= REG_FIELD(AFE4404_OFFDAC, 5, 9),
	[F_OFFDAC_AMB1]		= REG_FIELD(AFE4404_OFFDAC, 10, 14),
	[F_OFFDAC_LED2]		= REG_FIELD(AFE4404_OFFDAC, 15, 19),
};

/**
 * struct afe4404_data - AFE4404 device instance data
 * @dev: Device structure
 * @regmap: Register map of the device
 * @fields: Register fields of the device
 * @regulator: Pointer to the regulator for the IC
 * @trig: IIO trigger for this device
 * @irq: ADC_RDY line interrupt number
 * @buffer: Used to construct a scan to push to the iio buffer.
 */
struct afe4404_data {
	struct device *dev;
	struct regmap *regmap;
	struct regmap_field *fields[F_MAX_FIELDS];
	struct regulator *regulator;
	struct iio_trigger *trig;
	int irq;
	s32 buffer[10] __aligned(8);
};

enum afe4404_chan_id {
	LED2 = 1,
	ALED2,
	LED1,
	ALED1,
	LED2_ALED2,
	LED1_ALED1,
};

static const unsigned int afe4404_channel_values[] = {
	[LED2] = AFE440X_LED2VAL,
	[ALED2] = AFE440X_ALED2VAL,
	[LED1] = AFE440X_LED1VAL,
	[ALED1] = AFE440X_ALED1VAL,
	[LED2_ALED2] = AFE440X_LED2_ALED2VAL,
	[LED1_ALED1] = AFE440X_LED1_ALED1VAL,
};

static const unsigned int afe4404_channel_leds[] = {
	[LED2] = F_ILED2,
	[ALED2] = F_ILED3,
	[LED1] = F_ILED1,
};

static const unsigned int afe4404_channel_offdacs[] = {
	[LED2] = F_OFFDAC_LED2,
	[ALED2] = F_OFFDAC_AMB2,
	[LED1] = F_OFFDAC_LED1,
	[ALED1] = F_OFFDAC_AMB1,
};

static const struct iio_chan_spec afe4404_channels[] = {
	/* ADC values */
	AFE440X_INTENSITY_CHAN(LED2, BIT(IIO_CHAN_INFO_OFFSET)),
	AFE440X_INTENSITY_CHAN(ALED2, BIT(IIO_CHAN_INFO_OFFSET)),
	AFE440X_INTENSITY_CHAN(LED1, BIT(IIO_CHAN_INFO_OFFSET)),
	AFE440X_INTENSITY_CHAN(ALED1, BIT(IIO_CHAN_INFO_OFFSET)),
	AFE440X_INTENSITY_CHAN(LED2_ALED2, 0),
	AFE440X_INTENSITY_CHAN(LED1_ALED1, 0),
	/* LED current */
	AFE440X_CURRENT_CHAN(LED2),
	AFE440X_CURRENT_CHAN(ALED2),
	AFE440X_CURRENT_CHAN(LED1),
};

static const struct afe440x_val_table afe4404_res_table[] = {
	{ .integer = 500000, .fract = 0 },
	{ .integer = 250000, .fract = 0 },
	{ .integer = 100000, .fract = 0 },
	{ .integer = 50000, .fract = 0 },
	{ .integer = 25000, .fract = 0 },
	{ .integer = 10000, .fract = 0 },
	{ .integer = 1000000, .fract = 0 },
	{ .integer = 2000000, .fract = 0 },
};
AFE440X_TABLE_ATTR(in_intensity_resistance_available, afe4404_res_table);

static const struct afe440x_val_table afe4404_cap_table[] = {
	{ .integer = 0, .fract = 5000 },
	{ .integer = 0, .fract = 2500 },
	{ .integer = 0, .fract = 10000 },
	{ .integer = 0, .fract = 7500 },
	{ .integer = 0, .fract = 20000 },
	{ .integer = 0, .fract = 17500 },
	{ .integer = 0, .fract = 25000 },
	{ .integer = 0, .fract = 22500 },
};
AFE440X_TABLE_ATTR(in_intensity_capacitance_available, afe4404_cap_table);

static ssize_t afe440x_show_register(struct device *dev,
				     struct device_attribute *attr,
				     char *buf)
{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct afe4404_data *afe = iio_priv(indio_dev);
	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
	unsigned int reg_val;
	int vals[2];
	int ret;

	ret = regmap_field_read(afe->fields[afe440x_attr->field], &reg_val);
	if (ret)
		return ret;

	if (reg_val >= afe440x_attr->table_size)
		return -EINVAL;

	vals[0] = afe440x_attr->val_table[reg_val].integer;
	vals[1] = afe440x_attr->val_table[reg_val].fract;

	return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, 2, vals);
}

static ssize_t afe440x_store_register(struct device *dev,
				      struct device_attribute *attr,
				      const char *buf, size_t count)
{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct afe4404_data *afe = iio_priv(indio_dev);
	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
	int val, integer, fract, ret;

	ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
	if (ret)
		return ret;

	for (val = 0; val < afe440x_attr->table_size; val++)
		if (afe440x_attr->val_table[val].integer == integer &&
		    afe440x_attr->val_table[val].fract == fract)
			break;
	if (val == afe440x_attr->table_size)
		return -EINVAL;

	ret = regmap_field_write(afe->fields[afe440x_attr->field], val);
	if (ret)
		return ret;

	return count;
}

static AFE440X_ATTR(in_intensity1_resistance, F_TIA_GAIN_SEP, afe4404_res_table);
static AFE440X_ATTR(in_intensity1_capacitance, F_TIA_CF_SEP, afe4404_cap_table);

static AFE440X_ATTR(in_intensity2_resistance, F_TIA_GAIN_SEP, afe4404_res_table);
static AFE440X_ATTR(in_intensity2_capacitance, F_TIA_CF_SEP, afe4404_cap_table);

static AFE440X_ATTR(in_intensity3_resistance, F_TIA_GAIN, afe4404_res_table);
static AFE440X_ATTR(in_intensity3_capacitance, TIA_CF, afe4404_cap_table);

static AFE440X_ATTR(in_intensity4_resistance, F_TIA_GAIN, afe4404_res_table);
static AFE440X_ATTR(in_intensity4_capacitance, TIA_CF, afe4404_cap_table);

static struct attribute *afe440x_attributes[] = {
	&dev_attr_in_intensity_resistance_available.attr,
	&dev_attr_in_intensity_capacitance_available.attr,
	&afe440x_attr_in_intensity1_resistance.dev_attr.attr,
	&afe440x_attr_in_intensity1_capacitance.dev_attr.attr,
	&afe440x_attr_in_intensity2_resistance.dev_attr.attr,
	&afe440x_attr_in_intensity2_capacitance.dev_attr.attr,
	&afe440x_attr_in_intensity3_resistance.dev_attr.attr,
	&afe440x_attr_in_intensity3_capacitance.dev_attr.attr,
	&afe440x_attr_in_intensity4_resistance.dev_attr.attr,
	&afe440x_attr_in_intensity4_capacitance.dev_attr.attr,
	NULL
};

static const struct attribute_group afe440x_attribute_group = {
	.attrs = afe440x_attributes
};

static int afe4404_read_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *chan,
			    int *val, int *val2, long mask)
{
	struct afe4404_data *afe = iio_priv(indio_dev);
	unsigned int value_reg = afe4404_channel_values[chan->address];
	unsigned int led_field = afe4404_channel_leds[chan->address];
	unsigned int offdac_field = afe4404_channel_offdacs[chan->address];
	int ret;

	switch (chan->type) {
	case IIO_INTENSITY:
		switch (mask) {
		case IIO_CHAN_INFO_RAW:
			ret = regmap_read(afe->regmap, value_reg, val);
			if (ret)
				return ret;
			return IIO_VAL_INT;
		case IIO_CHAN_INFO_OFFSET:
			ret = regmap_field_read(afe->fields[offdac_field], val);
			if (ret)
				return ret;
			return IIO_VAL_INT;
		}
		break;
	case IIO_CURRENT:
		switch (mask) {
		case IIO_CHAN_INFO_RAW:
			ret = regmap_field_read(afe->fields[led_field], val);
			if (ret)
				return ret;
			return IIO_VAL_INT;
		case IIO_CHAN_INFO_SCALE:
			*val = 0;
			*val2 = 800000;
			return IIO_VAL_INT_PLUS_MICRO;
		}
		break;
	default:
		break;
	}

	return -EINVAL;
}

static int afe4404_write_raw(struct iio_dev *indio_dev,
			     struct iio_chan_spec const *chan,
			     int val, int val2, long mask)
{
	struct afe4404_data *afe = iio_priv(indio_dev);
	unsigned int led_field = afe4404_channel_leds[chan->address];
	unsigned int offdac_field = afe4404_channel_offdacs[chan->address];

	switch (chan->type) {
	case IIO_INTENSITY:
		switch (mask) {
		case IIO_CHAN_INFO_OFFSET:
			return regmap_field_write(afe->fields[offdac_field], val);
		}
		break;
	case IIO_CURRENT:
		switch (mask) {
		case IIO_CHAN_INFO_RAW:
			return regmap_field_write(afe->fields[led_field], val);
		}
		break;
	default:
		break;
	}

	return -EINVAL;
}

static const struct iio_info afe4404_iio_info = {
	.attrs = &afe440x_attribute_group,
	.read_raw = afe4404_read_raw,
	.write_raw = afe4404_write_raw,
};

static irqreturn_t afe4404_trigger_handler(int irq, void *private)
{
	struct iio_poll_func *pf = private;
	struct iio_dev *indio_dev = pf->indio_dev;
	struct afe4404_data *afe = iio_priv(indio_dev);
	int ret, bit, i = 0;

	for_each_set_bit(bit, indio_dev->active_scan_mask,
			 indio_dev->masklength) {
		ret = regmap_read(afe->regmap, afe4404_channel_values[bit],
				  &afe->buffer[i++]);
		if (ret)
			goto err;
	}

	iio_push_to_buffers_with_timestamp(indio_dev, afe->buffer,
					   pf->timestamp);
err:
	iio_trigger_notify_done(indio_dev->trig);

	return IRQ_HANDLED;
}

/* Default timings from data-sheet */
#define AFE4404_TIMING_PAIRS			\
	{ AFE440X_PRPCOUNT,	39999	},	\
	{ AFE440X_LED2LEDSTC,	0	},	\
	{ AFE440X_LED2LEDENDC,	398	},	\
	{ AFE440X_LED2STC,	80	},	\
	{ AFE440X_LED2ENDC,	398	},	\
	{ AFE440X_ADCRSTSTCT0,	5600	},	\
	{ AFE440X_ADCRSTENDCT0,	5606	},	\
	{ AFE440X_LED2CONVST,	5607	},	\
	{ AFE440X_LED2CONVEND,	6066	},	\
	{ AFE4404_LED3LEDSTC,	400	},	\
	{ AFE4404_LED3LEDENDC,	798	},	\
	{ AFE440X_ALED2STC,	480	},	\
	{ AFE440X_ALED2ENDC,	798	},	\
	{ AFE440X_ADCRSTSTCT1,	6068	},	\
	{ AFE440X_ADCRSTENDCT1,	6074	},	\
	{ AFE440X_ALED2CONVST,	6075	},	\
	{ AFE440X_ALED2CONVEND,	6534	},	\
	{ AFE440X_LED1LEDSTC,	800	},	\
	{ AFE440X_LED1LEDENDC,	1198	},	\
	{ AFE440X_LED1STC,	880	},	\
	{ AFE440X_LED1ENDC,	1198	},	\
	{ AFE440X_ADCRSTSTCT2,	6536	},	\
	{ AFE440X_ADCRSTENDCT2,	6542	},	\
	{ AFE440X_LED1CONVST,	6543	},	\
	{ AFE440X_LED1CONVEND,	7003	},	\
	{ AFE440X_ALED1STC,	1280	},	\
	{ AFE440X_ALED1ENDC,	1598	},	\
	{ AFE440X_ADCRSTSTCT3,	7005	},	\
	{ AFE440X_ADCRSTENDCT3,	7011	},	\
	{ AFE440X_ALED1CONVST,	7012	},	\
	{ AFE440X_ALED1CONVEND,	7471	},	\
	{ AFE440X_PDNCYCLESTC,	7671	},	\
	{ AFE440X_PDNCYCLEENDC,	39199	}

static const struct reg_sequence afe4404_reg_sequences[] = {
	AFE4404_TIMING_PAIRS,
	{ AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN },
	{ AFE4404_TIA_GAIN_SEP, AFE440X_TIAGAIN_ENSEPGAIN },
	{ AFE440X_CONTROL2, AFE440X_CONTROL2_OSC_ENABLE	},
};

static const struct regmap_range afe4404_yes_ranges[] = {
	regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL),
	regmap_reg_range(AFE4404_AVG_LED2_ALED2VAL, AFE4404_AVG_LED1_ALED1VAL),
};

static const struct regmap_access_table afe4404_volatile_table = {
	.yes_ranges = afe4404_yes_ranges,
	.n_yes_ranges = ARRAY_SIZE(afe4404_yes_ranges),
};

static const struct regmap_config afe4404_regmap_config = {
	.reg_bits = 8,
	.val_bits = 24,

	.max_register = AFE4404_AVG_LED1_ALED1VAL,
	.cache_type = REGCACHE_RBTREE,
	.volatile_table = &afe4404_volatile_table,
};

static const struct of_device_id afe4404_of_match[] = {
	{ .compatible = "ti,afe4404", },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, afe4404_of_match);

static int __maybe_unused afe4404_suspend(struct device *dev)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
	struct afe4404_data *afe = iio_priv(indio_dev);
	int ret;

	ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
				 AFE440X_CONTROL2_PDN_AFE,
				 AFE440X_CONTROL2_PDN_AFE);
	if (ret)
		return ret;

	ret = regulator_disable(afe->regulator);
	if (ret) {
		dev_err(dev, "Unable to disable regulator\n");
		return ret;
	}

	return 0;
}

static int __maybe_unused afe4404_resume(struct device *dev)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
	struct afe4404_data *afe = iio_priv(indio_dev);
	int ret;

	ret = regulator_enable(afe->regulator);
	if (ret) {
		dev_err(dev, "Unable to enable regulator\n");
		return ret;
	}

	ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
				 AFE440X_CONTROL2_PDN_AFE, 0);
	if (ret)
		return ret;

	return 0;
}

static SIMPLE_DEV_PM_OPS(afe4404_pm_ops, afe4404_suspend, afe4404_resume);

static int afe4404_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct iio_dev *indio_dev;
	struct afe4404_data *afe;
	int i, ret;

	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*afe));
	if (!indio_dev)
		return -ENOMEM;

	afe = iio_priv(indio_dev);
	i2c_set_clientdata(client, indio_dev);

	afe->dev = &client->dev;
	afe->irq = client->irq;

	afe->regmap = devm_regmap_init_i2c(client, &afe4404_regmap_config);
	if (IS_ERR(afe->regmap)) {
		dev_err(afe->dev, "Unable to allocate register map\n");
		return PTR_ERR(afe->regmap);
	}

	for (i = 0; i < F_MAX_FIELDS; i++) {
		afe->fields[i] = devm_regmap_field_alloc(afe->dev, afe->regmap,
							 afe4404_reg_fields[i]);
		if (IS_ERR(afe->fields[i])) {
			dev_err(afe->dev, "Unable to allocate regmap fields\n");
			return PTR_ERR(afe->fields[i]);
		}
	}

	afe->regulator = devm_regulator_get(afe->dev, "tx_sup");
	if (IS_ERR(afe->regulator))
		return dev_err_probe(afe->dev, PTR_ERR(afe->regulator),
				     "Unable to get regulator\n");

	ret = regulator_enable(afe->regulator);
	if (ret) {
		dev_err(afe->dev, "Unable to enable regulator\n");
		return ret;
	}

	ret = regmap_write(afe->regmap, AFE440X_CONTROL0,
			   AFE440X_CONTROL0_SW_RESET);
	if (ret) {
		dev_err(afe->dev, "Unable to reset device\n");
		goto disable_reg;
	}

	ret = regmap_multi_reg_write(afe->regmap, afe4404_reg_sequences,
				     ARRAY_SIZE(afe4404_reg_sequences));
	if (ret) {
		dev_err(afe->dev, "Unable to set register defaults\n");
		goto disable_reg;
	}

	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->channels = afe4404_channels;
	indio_dev->num_channels = ARRAY_SIZE(afe4404_channels);
	indio_dev->name = AFE4404_DRIVER_NAME;
	indio_dev->info = &afe4404_iio_info;

	if (afe->irq > 0) {
		afe->trig = devm_iio_trigger_alloc(afe->dev,
						   "%s-dev%d",
						   indio_dev->name,
						   iio_device_id(indio_dev));
		if (!afe->trig) {
			dev_err(afe->dev, "Unable to allocate IIO trigger\n");
			ret = -ENOMEM;
			goto disable_reg;
		}

		iio_trigger_set_drvdata(afe->trig, indio_dev);

		ret = iio_trigger_register(afe->trig);
		if (ret) {
			dev_err(afe->dev, "Unable to register IIO trigger\n");
			goto disable_reg;
		}

		ret = devm_request_threaded_irq(afe->dev, afe->irq,
						iio_trigger_generic_data_rdy_poll,
						NULL, IRQF_ONESHOT,
						AFE4404_DRIVER_NAME,
						afe->trig);
		if (ret) {
			dev_err(afe->dev, "Unable to request IRQ\n");
			goto disable_reg;
		}
	}

	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
					 afe4404_trigger_handler, NULL);
	if (ret) {
		dev_err(afe->dev, "Unable to setup buffer\n");
		goto unregister_trigger;
	}

	ret = iio_device_register(indio_dev);
	if (ret) {
		dev_err(afe->dev, "Unable to register IIO device\n");
		goto unregister_triggered_buffer;
	}

	return 0;

unregister_triggered_buffer:
	iio_triggered_buffer_cleanup(indio_dev);
unregister_trigger:
	if (afe->irq > 0)
		iio_trigger_unregister(afe->trig);
disable_reg:
	regulator_disable(afe->regulator);

	return ret;
}

static int afe4404_remove(struct i2c_client *client)
{
	struct iio_dev *indio_dev = i2c_get_clientdata(client);
	struct afe4404_data *afe = iio_priv(indio_dev);
	int ret;

	iio_device_unregister(indio_dev);

	iio_triggered_buffer_cleanup(indio_dev);

	if (afe->irq > 0)
		iio_trigger_unregister(afe->trig);

	ret = regulator_disable(afe->regulator);
	if (ret) {
		dev_err(afe->dev, "Unable to disable regulator\n");
		return ret;
	}

	return 0;
}

static const struct i2c_device_id afe4404_ids[] = {
	{ "afe4404", 0 },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(i2c, afe4404_ids);

static struct i2c_driver afe4404_i2c_driver = {
	.driver = {
		.name = AFE4404_DRIVER_NAME,
		.of_match_table = afe4404_of_match,
		.pm = &afe4404_pm_ops,
	},
	.probe = afe4404_probe,
	.remove = afe4404_remove,
	.id_table = afe4404_ids,
};
module_i2c_driver(afe4404_i2c_driver);

MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
MODULE_DESCRIPTION("TI AFE4404 Heart Rate Monitor and Pulse Oximeter AFE");
MODULE_LICENSE("GPL v2");