1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AFE4404 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/i2c.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/regmap.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 AFE4404_DRIVER_NAME		"afe4404"
29
30/* AFE4404 registers */
31#define AFE4404_TIA_GAIN_SEP		0x20
32#define AFE4404_TIA_GAIN		0x21
33#define AFE4404_PROG_TG_STC		0x34
34#define AFE4404_PROG_TG_ENDC		0x35
35#define AFE4404_LED3LEDSTC		0x36
36#define AFE4404_LED3LEDENDC		0x37
37#define AFE4404_CLKDIV_PRF		0x39
38#define AFE4404_OFFDAC			0x3a
39#define AFE4404_DEC			0x3d
40#define AFE4404_AVG_LED2_ALED2VAL	0x3f
41#define AFE4404_AVG_LED1_ALED1VAL	0x40
42
43/* AFE4404 CONTROL2 register fields */
44#define AFE440X_CONTROL2_OSC_ENABLE	BIT(9)
45
46enum afe4404_fields {
47	/* Gains */
48	F_TIA_GAIN_SEP, F_TIA_CF_SEP,
49	F_TIA_GAIN, TIA_CF,
50
51	/* LED Current */
52	F_ILED1, F_ILED2, F_ILED3,
53
54	/* Offset DAC */
55	F_OFFDAC_AMB2, F_OFFDAC_LED1, F_OFFDAC_AMB1, F_OFFDAC_LED2,
56
57	/* sentinel */
58	F_MAX_FIELDS
59};
60
61static const struct reg_field afe4404_reg_fields[] = {
62	/* Gains */
63	[F_TIA_GAIN_SEP]	= REG_FIELD(AFE4404_TIA_GAIN_SEP, 0, 2),
64	[F_TIA_CF_SEP]		= REG_FIELD(AFE4404_TIA_GAIN_SEP, 3, 5),
65	[F_TIA_GAIN]		= REG_FIELD(AFE4404_TIA_GAIN, 0, 2),
66	[TIA_CF]		= REG_FIELD(AFE4404_TIA_GAIN, 3, 5),
67	/* LED Current */
68	[F_ILED1]		= REG_FIELD(AFE440X_LEDCNTRL, 0, 5),
69	[F_ILED2]		= REG_FIELD(AFE440X_LEDCNTRL, 6, 11),
70	[F_ILED3]		= REG_FIELD(AFE440X_LEDCNTRL, 12, 17),
71	/* Offset DAC */
72	[F_OFFDAC_AMB2]		= REG_FIELD(AFE4404_OFFDAC, 0, 4),
73	[F_OFFDAC_LED1]		= REG_FIELD(AFE4404_OFFDAC, 5, 9),
74	[F_OFFDAC_AMB1]		= REG_FIELD(AFE4404_OFFDAC, 10, 14),
75	[F_OFFDAC_LED2]		= REG_FIELD(AFE4404_OFFDAC, 15, 19),
76};
77
78/**
79 * struct afe4404_data - AFE4404 device instance data
80 * @dev: Device structure
81 * @regmap: Register map of the device
82 * @fields: Register fields of the device
83 * @regulator: Pointer to the regulator for the IC
84 * @trig: IIO trigger for this device
85 * @irq: ADC_RDY line interrupt number
86 * @buffer: Used to construct a scan to push to the iio buffer.
87 */
88struct afe4404_data {
89	struct device *dev;
90	struct regmap *regmap;
91	struct regmap_field *fields[F_MAX_FIELDS];
92	struct regulator *regulator;
93	struct iio_trigger *trig;
94	int irq;
95	s32 buffer[10] __aligned(8);
96};
97
98enum afe4404_chan_id {
99	LED2 = 1,
100	ALED2,
101	LED1,
102	ALED1,
103	LED2_ALED2,
104	LED1_ALED1,
105};
106
107static const unsigned int afe4404_channel_values[] = {
108	[LED2] = AFE440X_LED2VAL,
109	[ALED2] = AFE440X_ALED2VAL,
110	[LED1] = AFE440X_LED1VAL,
111	[ALED1] = AFE440X_ALED1VAL,
112	[LED2_ALED2] = AFE440X_LED2_ALED2VAL,
113	[LED1_ALED1] = AFE440X_LED1_ALED1VAL,
114};
115
116static const unsigned int afe4404_channel_leds[] = {
117	[LED2] = F_ILED2,
118	[ALED2] = F_ILED3,
119	[LED1] = F_ILED1,
120};
121
122static const unsigned int afe4404_channel_offdacs[] = {
123	[LED2] = F_OFFDAC_LED2,
124	[ALED2] = F_OFFDAC_AMB2,
125	[LED1] = F_OFFDAC_LED1,
126	[ALED1] = F_OFFDAC_AMB1,
127};
128
129static const struct iio_chan_spec afe4404_channels[] = {
130	/* ADC values */
131	AFE440X_INTENSITY_CHAN(LED2, BIT(IIO_CHAN_INFO_OFFSET)),
132	AFE440X_INTENSITY_CHAN(ALED2, BIT(IIO_CHAN_INFO_OFFSET)),
133	AFE440X_INTENSITY_CHAN(LED1, BIT(IIO_CHAN_INFO_OFFSET)),
134	AFE440X_INTENSITY_CHAN(ALED1, BIT(IIO_CHAN_INFO_OFFSET)),
135	AFE440X_INTENSITY_CHAN(LED2_ALED2, 0),
136	AFE440X_INTENSITY_CHAN(LED1_ALED1, 0),
137	/* LED current */
138	AFE440X_CURRENT_CHAN(LED2),
139	AFE440X_CURRENT_CHAN(ALED2),
140	AFE440X_CURRENT_CHAN(LED1),
141};
142
143static const struct afe440x_val_table afe4404_res_table[] = {
144	{ .integer = 500000, .fract = 0 },
145	{ .integer = 250000, .fract = 0 },
146	{ .integer = 100000, .fract = 0 },
147	{ .integer = 50000, .fract = 0 },
148	{ .integer = 25000, .fract = 0 },
149	{ .integer = 10000, .fract = 0 },
150	{ .integer = 1000000, .fract = 0 },
151	{ .integer = 2000000, .fract = 0 },
152};
153AFE440X_TABLE_ATTR(in_intensity_resistance_available, afe4404_res_table);
154
155static const struct afe440x_val_table afe4404_cap_table[] = {
156	{ .integer = 0, .fract = 5000 },
157	{ .integer = 0, .fract = 2500 },
158	{ .integer = 0, .fract = 10000 },
159	{ .integer = 0, .fract = 7500 },
160	{ .integer = 0, .fract = 20000 },
161	{ .integer = 0, .fract = 17500 },
162	{ .integer = 0, .fract = 25000 },
163	{ .integer = 0, .fract = 22500 },
164};
165AFE440X_TABLE_ATTR(in_intensity_capacitance_available, afe4404_cap_table);
166
167static ssize_t afe440x_show_register(struct device *dev,
168				     struct device_attribute *attr,
169				     char *buf)
170{
171	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
172	struct afe4404_data *afe = iio_priv(indio_dev);
173	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
174	unsigned int reg_val;
175	int vals[2];
176	int ret;
177
178	ret = regmap_field_read(afe->fields[afe440x_attr->field], &reg_val);
179	if (ret)
180		return ret;
181
182	if (reg_val >= afe440x_attr->table_size)
183		return -EINVAL;
184
185	vals[0] = afe440x_attr->val_table[reg_val].integer;
186	vals[1] = afe440x_attr->val_table[reg_val].fract;
187
188	return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, 2, vals);
189}
190
191static ssize_t afe440x_store_register(struct device *dev,
192				      struct device_attribute *attr,
193				      const char *buf, size_t count)
194{
195	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
196	struct afe4404_data *afe = iio_priv(indio_dev);
197	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
198	int val, integer, fract, ret;
199
200	ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
201	if (ret)
202		return ret;
203
204	for (val = 0; val < afe440x_attr->table_size; val++)
205		if (afe440x_attr->val_table[val].integer == integer &&
206		    afe440x_attr->val_table[val].fract == fract)
207			break;
208	if (val == afe440x_attr->table_size)
209		return -EINVAL;
210
211	ret = regmap_field_write(afe->fields[afe440x_attr->field], val);
212	if (ret)
213		return ret;
214
215	return count;
216}
217
218static AFE440X_ATTR(in_intensity1_resistance, F_TIA_GAIN_SEP, afe4404_res_table);
219static AFE440X_ATTR(in_intensity1_capacitance, F_TIA_CF_SEP, afe4404_cap_table);
220
221static AFE440X_ATTR(in_intensity2_resistance, F_TIA_GAIN_SEP, afe4404_res_table);
222static AFE440X_ATTR(in_intensity2_capacitance, F_TIA_CF_SEP, afe4404_cap_table);
223
224static AFE440X_ATTR(in_intensity3_resistance, F_TIA_GAIN, afe4404_res_table);
225static AFE440X_ATTR(in_intensity3_capacitance, TIA_CF, afe4404_cap_table);
226
227static AFE440X_ATTR(in_intensity4_resistance, F_TIA_GAIN, afe4404_res_table);
228static AFE440X_ATTR(in_intensity4_capacitance, TIA_CF, afe4404_cap_table);
229
230static struct attribute *afe440x_attributes[] = {
231	&dev_attr_in_intensity_resistance_available.attr,
232	&dev_attr_in_intensity_capacitance_available.attr,
233	&afe440x_attr_in_intensity1_resistance.dev_attr.attr,
234	&afe440x_attr_in_intensity1_capacitance.dev_attr.attr,
235	&afe440x_attr_in_intensity2_resistance.dev_attr.attr,
236	&afe440x_attr_in_intensity2_capacitance.dev_attr.attr,
237	&afe440x_attr_in_intensity3_resistance.dev_attr.attr,
238	&afe440x_attr_in_intensity3_capacitance.dev_attr.attr,
239	&afe440x_attr_in_intensity4_resistance.dev_attr.attr,
240	&afe440x_attr_in_intensity4_capacitance.dev_attr.attr,
241	NULL
242};
243
244static const struct attribute_group afe440x_attribute_group = {
245	.attrs = afe440x_attributes
246};
247
248static int afe4404_read_raw(struct iio_dev *indio_dev,
249			    struct iio_chan_spec const *chan,
250			    int *val, int *val2, long mask)
251{
252	struct afe4404_data *afe = iio_priv(indio_dev);
253	unsigned int value_reg, led_field, offdac_field;
254	int ret;
255
256	switch (chan->type) {
257	case IIO_INTENSITY:
258		switch (mask) {
259		case IIO_CHAN_INFO_RAW:
260			value_reg = afe4404_channel_values[chan->address];
261			ret = regmap_read(afe->regmap, value_reg, val);
262			if (ret)
263				return ret;
264			return IIO_VAL_INT;
265		case IIO_CHAN_INFO_OFFSET:
266			offdac_field = afe4404_channel_offdacs[chan->address];
267			ret = regmap_field_read(afe->fields[offdac_field], val);
268			if (ret)
269				return ret;
270			return IIO_VAL_INT;
271		}
272		break;
273	case IIO_CURRENT:
274		switch (mask) {
275		case IIO_CHAN_INFO_RAW:
276			led_field = afe4404_channel_leds[chan->address];
277			ret = regmap_field_read(afe->fields[led_field], val);
278			if (ret)
279				return ret;
280			return IIO_VAL_INT;
281		case IIO_CHAN_INFO_SCALE:
282			*val = 0;
283			*val2 = 800000;
284			return IIO_VAL_INT_PLUS_MICRO;
285		}
286		break;
287	default:
288		break;
289	}
290
291	return -EINVAL;
292}
293
294static int afe4404_write_raw(struct iio_dev *indio_dev,
295			     struct iio_chan_spec const *chan,
296			     int val, int val2, long mask)
297{
298	struct afe4404_data *afe = iio_priv(indio_dev);
299	unsigned int led_field, offdac_field;
300
301	switch (chan->type) {
302	case IIO_INTENSITY:
303		switch (mask) {
304		case IIO_CHAN_INFO_OFFSET:
305			offdac_field = afe4404_channel_offdacs[chan->address];
306			return regmap_field_write(afe->fields[offdac_field], val);
307		}
308		break;
309	case IIO_CURRENT:
310		switch (mask) {
311		case IIO_CHAN_INFO_RAW:
312			led_field = afe4404_channel_leds[chan->address];
313			return regmap_field_write(afe->fields[led_field], val);
314		}
315		break;
316	default:
317		break;
318	}
319
320	return -EINVAL;
321}
322
323static const struct iio_info afe4404_iio_info = {
324	.attrs = &afe440x_attribute_group,
325	.read_raw = afe4404_read_raw,
326	.write_raw = afe4404_write_raw,
327};
328
329static irqreturn_t afe4404_trigger_handler(int irq, void *private)
330{
331	struct iio_poll_func *pf = private;
332	struct iio_dev *indio_dev = pf->indio_dev;
333	struct afe4404_data *afe = iio_priv(indio_dev);
334	int ret, bit, i = 0;
335
336	for_each_set_bit(bit, indio_dev->active_scan_mask,
337			 indio_dev->masklength) {
338		ret = regmap_read(afe->regmap, afe4404_channel_values[bit],
339				  &afe->buffer[i++]);
340		if (ret)
341			goto err;
342	}
343
344	iio_push_to_buffers_with_timestamp(indio_dev, afe->buffer,
345					   pf->timestamp);
346err:
347	iio_trigger_notify_done(indio_dev->trig);
348
349	return IRQ_HANDLED;
350}
351
352static const struct iio_trigger_ops afe4404_trigger_ops = {
353};
354
355/* Default timings from data-sheet */
356#define AFE4404_TIMING_PAIRS			\
357	{ AFE440X_PRPCOUNT,	39999	},	\
358	{ AFE440X_LED2LEDSTC,	0	},	\
359	{ AFE440X_LED2LEDENDC,	398	},	\
360	{ AFE440X_LED2STC,	80	},	\
361	{ AFE440X_LED2ENDC,	398	},	\
362	{ AFE440X_ADCRSTSTCT0,	5600	},	\
363	{ AFE440X_ADCRSTENDCT0,	5606	},	\
364	{ AFE440X_LED2CONVST,	5607	},	\
365	{ AFE440X_LED2CONVEND,	6066	},	\
366	{ AFE4404_LED3LEDSTC,	400	},	\
367	{ AFE4404_LED3LEDENDC,	798	},	\
368	{ AFE440X_ALED2STC,	480	},	\
369	{ AFE440X_ALED2ENDC,	798	},	\
370	{ AFE440X_ADCRSTSTCT1,	6068	},	\
371	{ AFE440X_ADCRSTENDCT1,	6074	},	\
372	{ AFE440X_ALED2CONVST,	6075	},	\
373	{ AFE440X_ALED2CONVEND,	6534	},	\
374	{ AFE440X_LED1LEDSTC,	800	},	\
375	{ AFE440X_LED1LEDENDC,	1198	},	\
376	{ AFE440X_LED1STC,	880	},	\
377	{ AFE440X_LED1ENDC,	1198	},	\
378	{ AFE440X_ADCRSTSTCT2,	6536	},	\
379	{ AFE440X_ADCRSTENDCT2,	6542	},	\
380	{ AFE440X_LED1CONVST,	6543	},	\
381	{ AFE440X_LED1CONVEND,	7003	},	\
382	{ AFE440X_ALED1STC,	1280	},	\
383	{ AFE440X_ALED1ENDC,	1598	},	\
384	{ AFE440X_ADCRSTSTCT3,	7005	},	\
385	{ AFE440X_ADCRSTENDCT3,	7011	},	\
386	{ AFE440X_ALED1CONVST,	7012	},	\
387	{ AFE440X_ALED1CONVEND,	7471	},	\
388	{ AFE440X_PDNCYCLESTC,	7671	},	\
389	{ AFE440X_PDNCYCLEENDC,	39199	}
390
391static const struct reg_sequence afe4404_reg_sequences[] = {
392	AFE4404_TIMING_PAIRS,
393	{ AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN },
394	{ AFE4404_TIA_GAIN_SEP, AFE440X_TIAGAIN_ENSEPGAIN },
395	{ AFE440X_CONTROL2, AFE440X_CONTROL2_OSC_ENABLE	},
396};
397
398static const struct regmap_range afe4404_yes_ranges[] = {
399	regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL),
400	regmap_reg_range(AFE4404_AVG_LED2_ALED2VAL, AFE4404_AVG_LED1_ALED1VAL),
401};
402
403static const struct regmap_access_table afe4404_volatile_table = {
404	.yes_ranges = afe4404_yes_ranges,
405	.n_yes_ranges = ARRAY_SIZE(afe4404_yes_ranges),
406};
407
408static const struct regmap_config afe4404_regmap_config = {
409	.reg_bits = 8,
410	.val_bits = 24,
411
412	.max_register = AFE4404_AVG_LED1_ALED1VAL,
413	.cache_type = REGCACHE_RBTREE,
414	.volatile_table = &afe4404_volatile_table,
415};
416
417static const struct of_device_id afe4404_of_match[] = {
418	{ .compatible = "ti,afe4404", },
419	{ /* sentinel */ }
420};
421MODULE_DEVICE_TABLE(of, afe4404_of_match);
422
423static int __maybe_unused afe4404_suspend(struct device *dev)
424{
425	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
426	struct afe4404_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
444static int __maybe_unused afe4404_resume(struct device *dev)
445{
446	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
447	struct afe4404_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
464static SIMPLE_DEV_PM_OPS(afe4404_pm_ops, afe4404_suspend, afe4404_resume);
465
466static int afe4404_probe(struct i2c_client *client,
467			 const struct i2c_device_id *id)
468{
469	struct iio_dev *indio_dev;
470	struct afe4404_data *afe;
471	int i, ret;
472
473	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*afe));
474	if (!indio_dev)
475		return -ENOMEM;
476
477	afe = iio_priv(indio_dev);
478	i2c_set_clientdata(client, indio_dev);
479
480	afe->dev = &client->dev;
481	afe->irq = client->irq;
482
483	afe->regmap = devm_regmap_init_i2c(client, &afe4404_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							 afe4404_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 disable_reg;
514	}
515
516	ret = regmap_multi_reg_write(afe->regmap, afe4404_reg_sequences,
517				     ARRAY_SIZE(afe4404_reg_sequences));
518	if (ret) {
519		dev_err(afe->dev, "Unable to set register defaults\n");
520		goto disable_reg;
521	}
522
523	indio_dev->modes = INDIO_DIRECT_MODE;
524	indio_dev->channels = afe4404_channels;
525	indio_dev->num_channels = ARRAY_SIZE(afe4404_channels);
526	indio_dev->name = AFE4404_DRIVER_NAME;
527	indio_dev->info = &afe4404_iio_info;
528
529	if (afe->irq > 0) {
530		afe->trig = devm_iio_trigger_alloc(afe->dev,
531						   "%s-dev%d",
532						   indio_dev->name,
533						   indio_dev->id);
534		if (!afe->trig) {
535			dev_err(afe->dev, "Unable to allocate IIO trigger\n");
536			ret = -ENOMEM;
537			goto disable_reg;
538		}
539
540		iio_trigger_set_drvdata(afe->trig, indio_dev);
541
542		afe->trig->ops = &afe4404_trigger_ops;
543		afe->trig->dev.parent = afe->dev;
544
545		ret = iio_trigger_register(afe->trig);
546		if (ret) {
547			dev_err(afe->dev, "Unable to register IIO trigger\n");
548			goto disable_reg;
549		}
550
551		ret = devm_request_threaded_irq(afe->dev, afe->irq,
552						iio_trigger_generic_data_rdy_poll,
553						NULL, IRQF_ONESHOT,
554						AFE4404_DRIVER_NAME,
555						afe->trig);
556		if (ret) {
557			dev_err(afe->dev, "Unable to request IRQ\n");
558			goto disable_reg;
559		}
560	}
561
562	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
563					 afe4404_trigger_handler, NULL);
564	if (ret) {
565		dev_err(afe->dev, "Unable to setup buffer\n");
566		goto unregister_trigger;
567	}
568
569	ret = iio_device_register(indio_dev);
570	if (ret) {
571		dev_err(afe->dev, "Unable to register IIO device\n");
572		goto unregister_triggered_buffer;
573	}
574
575	return 0;
576
577unregister_triggered_buffer:
578	iio_triggered_buffer_cleanup(indio_dev);
579unregister_trigger:
580	if (afe->irq > 0)
581		iio_trigger_unregister(afe->trig);
582disable_reg:
583	regulator_disable(afe->regulator);
584
585	return ret;
586}
587
588static int afe4404_remove(struct i2c_client *client)
589{
590	struct iio_dev *indio_dev = i2c_get_clientdata(client);
591	struct afe4404_data *afe = iio_priv(indio_dev);
592	int ret;
593
594	iio_device_unregister(indio_dev);
595
596	iio_triggered_buffer_cleanup(indio_dev);
597
598	if (afe->irq > 0)
599		iio_trigger_unregister(afe->trig);
600
601	ret = regulator_disable(afe->regulator);
602	if (ret) {
603		dev_err(afe->dev, "Unable to disable regulator\n");
604		return ret;
605	}
606
607	return 0;
608}
609
610static const struct i2c_device_id afe4404_ids[] = {
611	{ "afe4404", 0 },
612	{ /* sentinel */ }
613};
614MODULE_DEVICE_TABLE(i2c, afe4404_ids);
615
616static struct i2c_driver afe4404_i2c_driver = {
617	.driver = {
618		.name = AFE4404_DRIVER_NAME,
619		.of_match_table = afe4404_of_match,
620		.pm = &afe4404_pm_ops,
621	},
622	.probe = afe4404_probe,
623	.remove = afe4404_remove,
624	.id_table = afe4404_ids,
625};
626module_i2c_driver(afe4404_i2c_driver);
627
628MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
629MODULE_DESCRIPTION("TI AFE4404 Heart Rate Monitor and Pulse Oximeter AFE");
630MODULE_LICENSE("GPL v2");
631