xref: /openbmc/linux/drivers/iio/health/afe4403.c (revision 110e6f26)
1 /*
2  * AFE4403 Heart Rate Monitors and Low-Cost Pulse Oximeters
3  *
4  * Copyright (C) 2015 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 /* AFE4403 GAIN register fields */
43 #define AFE4403_TIAGAIN_RES_MASK	GENMASK(2, 0)
44 #define AFE4403_TIAGAIN_RES_SHIFT	0
45 #define AFE4403_TIAGAIN_CAP_MASK	GENMASK(7, 3)
46 #define AFE4403_TIAGAIN_CAP_SHIFT	3
47 
48 /* AFE4403 LEDCNTRL register fields */
49 #define AFE440X_LEDCNTRL_LED1_MASK		GENMASK(15, 8)
50 #define AFE440X_LEDCNTRL_LED1_SHIFT		8
51 #define AFE440X_LEDCNTRL_LED2_MASK		GENMASK(7, 0)
52 #define AFE440X_LEDCNTRL_LED2_SHIFT		0
53 #define AFE440X_LEDCNTRL_LED_RANGE_MASK		GENMASK(17, 16)
54 #define AFE440X_LEDCNTRL_LED_RANGE_SHIFT	16
55 
56 /* AFE4403 CONTROL2 register fields */
57 #define AFE440X_CONTROL2_PWR_DWN_TX	BIT(2)
58 #define AFE440X_CONTROL2_EN_SLOW_DIAG	BIT(8)
59 #define AFE440X_CONTROL2_DIAG_OUT_TRI	BIT(10)
60 #define AFE440X_CONTROL2_TX_BRDG_MOD	BIT(11)
61 #define AFE440X_CONTROL2_TX_REF_MASK	GENMASK(18, 17)
62 #define AFE440X_CONTROL2_TX_REF_SHIFT	17
63 
64 /* AFE4404 NULL fields */
65 #define NULL_MASK	0
66 #define NULL_SHIFT	0
67 
68 /* AFE4403 LEDCNTRL values */
69 #define AFE440X_LEDCNTRL_RANGE_TX_HALF	0x1
70 #define AFE440X_LEDCNTRL_RANGE_TX_FULL	0x2
71 #define AFE440X_LEDCNTRL_RANGE_TX_OFF	0x3
72 
73 /* AFE4403 CONTROL2 values */
74 #define AFE440X_CONTROL2_TX_REF_025	0x0
75 #define AFE440X_CONTROL2_TX_REF_050	0x1
76 #define AFE440X_CONTROL2_TX_REF_100	0x2
77 #define AFE440X_CONTROL2_TX_REF_075	0x3
78 
79 /* AFE4403 CONTROL3 values */
80 #define AFE440X_CONTROL3_CLK_DIV_2	0x0
81 #define AFE440X_CONTROL3_CLK_DIV_4	0x2
82 #define AFE440X_CONTROL3_CLK_DIV_6	0x3
83 #define AFE440X_CONTROL3_CLK_DIV_8	0x4
84 #define AFE440X_CONTROL3_CLK_DIV_12	0x5
85 #define AFE440X_CONTROL3_CLK_DIV_1	0x7
86 
87 /* AFE4403 TIAGAIN_CAP values */
88 #define AFE4403_TIAGAIN_CAP_5_P		0x0
89 #define AFE4403_TIAGAIN_CAP_10_P	0x1
90 #define AFE4403_TIAGAIN_CAP_20_P	0x2
91 #define AFE4403_TIAGAIN_CAP_30_P	0x3
92 #define AFE4403_TIAGAIN_CAP_55_P	0x8
93 #define AFE4403_TIAGAIN_CAP_155_P	0x10
94 
95 /* AFE4403 TIAGAIN_RES values */
96 #define AFE4403_TIAGAIN_RES_500_K	0x0
97 #define AFE4403_TIAGAIN_RES_250_K	0x1
98 #define AFE4403_TIAGAIN_RES_100_K	0x2
99 #define AFE4403_TIAGAIN_RES_50_K	0x3
100 #define AFE4403_TIAGAIN_RES_25_K	0x4
101 #define AFE4403_TIAGAIN_RES_10_K	0x5
102 #define AFE4403_TIAGAIN_RES_1_M		0x6
103 #define AFE4403_TIAGAIN_RES_NONE	0x7
104 
105 /**
106  * struct afe4403_data
107  * @dev - Device structure
108  * @spi - SPI device handle
109  * @regmap - Register map of the device
110  * @regulator - Pointer to the regulator for the IC
111  * @trig - IIO trigger for this device
112  * @irq - ADC_RDY line interrupt number
113  */
114 struct afe4403_data {
115 	struct device *dev;
116 	struct spi_device *spi;
117 	struct regmap *regmap;
118 	struct regulator *regulator;
119 	struct iio_trigger *trig;
120 	int irq;
121 };
122 
123 enum afe4403_chan_id {
124 	LED1,
125 	ALED1,
126 	LED2,
127 	ALED2,
128 	LED1_ALED1,
129 	LED2_ALED2,
130 	ILED1,
131 	ILED2,
132 };
133 
134 static const struct afe440x_reg_info afe4403_reg_info[] = {
135 	[LED1] = AFE440X_REG_INFO(AFE440X_LED1VAL, 0, NULL),
136 	[ALED1] = AFE440X_REG_INFO(AFE440X_ALED1VAL, 0, NULL),
137 	[LED2] = AFE440X_REG_INFO(AFE440X_LED2VAL, 0, NULL),
138 	[ALED2] = AFE440X_REG_INFO(AFE440X_ALED2VAL, 0, NULL),
139 	[LED1_ALED1] = AFE440X_REG_INFO(AFE440X_LED1_ALED1VAL, 0, NULL),
140 	[LED2_ALED2] = AFE440X_REG_INFO(AFE440X_LED2_ALED2VAL, 0, NULL),
141 	[ILED1] = AFE440X_REG_INFO(AFE440X_LEDCNTRL, 0, AFE440X_LEDCNTRL_LED1),
142 	[ILED2] = AFE440X_REG_INFO(AFE440X_LEDCNTRL, 0, AFE440X_LEDCNTRL_LED2),
143 };
144 
145 static const struct iio_chan_spec afe4403_channels[] = {
146 	/* ADC values */
147 	AFE440X_INTENSITY_CHAN(LED1, "led1", 0),
148 	AFE440X_INTENSITY_CHAN(ALED1, "led1_ambient", 0),
149 	AFE440X_INTENSITY_CHAN(LED2, "led2", 0),
150 	AFE440X_INTENSITY_CHAN(ALED2, "led2_ambient", 0),
151 	AFE440X_INTENSITY_CHAN(LED1_ALED1, "led1-led1_ambient", 0),
152 	AFE440X_INTENSITY_CHAN(LED2_ALED2, "led2-led2_ambient", 0),
153 	/* LED current */
154 	AFE440X_CURRENT_CHAN(ILED1, "led1"),
155 	AFE440X_CURRENT_CHAN(ILED2, "led2"),
156 };
157 
158 static const struct afe440x_val_table afe4403_res_table[] = {
159 	{ 500000 }, { 250000 }, { 100000 }, { 50000 },
160 	{ 25000 }, { 10000 }, { 1000000 }, { 0 },
161 };
162 AFE440X_TABLE_ATTR(tia_resistance_available, afe4403_res_table);
163 
164 static const struct afe440x_val_table afe4403_cap_table[] = {
165 	{ 0, 5000 }, { 0, 10000 }, { 0, 20000 }, { 0, 25000 },
166 	{ 0, 30000 }, { 0, 35000 }, { 0, 45000 }, { 0, 50000 },
167 	{ 0, 55000 }, { 0, 60000 }, { 0, 70000 }, { 0, 75000 },
168 	{ 0, 80000 }, { 0, 85000 }, { 0, 95000 }, { 0, 100000 },
169 	{ 0, 155000 }, { 0, 160000 }, { 0, 170000 }, { 0, 175000 },
170 	{ 0, 180000 }, { 0, 185000 }, { 0, 195000 }, { 0, 200000 },
171 	{ 0, 205000 }, { 0, 210000 }, { 0, 220000 }, { 0, 225000 },
172 	{ 0, 230000 }, { 0, 235000 }, { 0, 245000 }, { 0, 250000 },
173 };
174 AFE440X_TABLE_ATTR(tia_capacitance_available, afe4403_cap_table);
175 
176 static ssize_t afe440x_show_register(struct device *dev,
177 				     struct device_attribute *attr,
178 				     char *buf)
179 {
180 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
181 	struct afe4403_data *afe = iio_priv(indio_dev);
182 	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
183 	unsigned int reg_val, type;
184 	int vals[2];
185 	int ret, val_len;
186 
187 	ret = regmap_read(afe->regmap, afe440x_attr->reg, &reg_val);
188 	if (ret)
189 		return ret;
190 
191 	reg_val &= afe440x_attr->mask;
192 	reg_val >>= afe440x_attr->shift;
193 
194 	switch (afe440x_attr->type) {
195 	case SIMPLE:
196 		type = IIO_VAL_INT;
197 		val_len = 1;
198 		vals[0] = reg_val;
199 		break;
200 	case RESISTANCE:
201 	case CAPACITANCE:
202 		type = IIO_VAL_INT_PLUS_MICRO;
203 		val_len = 2;
204 		if (reg_val < afe440x_attr->table_size) {
205 			vals[0] = afe440x_attr->val_table[reg_val].integer;
206 			vals[1] = afe440x_attr->val_table[reg_val].fract;
207 			break;
208 		}
209 		return -EINVAL;
210 	default:
211 		return -EINVAL;
212 	}
213 
214 	return iio_format_value(buf, type, val_len, vals);
215 }
216 
217 static ssize_t afe440x_store_register(struct device *dev,
218 				      struct device_attribute *attr,
219 				      const char *buf, size_t count)
220 {
221 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
222 	struct afe4403_data *afe = iio_priv(indio_dev);
223 	struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
224 	int val, integer, fract, ret;
225 
226 	ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
227 	if (ret)
228 		return ret;
229 
230 	switch (afe440x_attr->type) {
231 	case SIMPLE:
232 		val = integer;
233 		break;
234 	case RESISTANCE:
235 	case CAPACITANCE:
236 		for (val = 0; val < afe440x_attr->table_size; val++)
237 			if (afe440x_attr->val_table[val].integer == integer &&
238 			    afe440x_attr->val_table[val].fract == fract)
239 				break;
240 		if (val == afe440x_attr->table_size)
241 			return -EINVAL;
242 		break;
243 	default:
244 		return -EINVAL;
245 	}
246 
247 	ret = regmap_update_bits(afe->regmap, afe440x_attr->reg,
248 				 afe440x_attr->mask,
249 				 (val << afe440x_attr->shift));
250 	if (ret)
251 		return ret;
252 
253 	return count;
254 }
255 
256 static AFE440X_ATTR(tia_separate_en, AFE4403_TIAGAIN, AFE440X_TIAGAIN_ENSEPGAIN, SIMPLE, NULL, 0);
257 
258 static AFE440X_ATTR(tia_resistance1, AFE4403_TIAGAIN, AFE4403_TIAGAIN_RES, RESISTANCE, afe4403_res_table, ARRAY_SIZE(afe4403_res_table));
259 static AFE440X_ATTR(tia_capacitance1, AFE4403_TIAGAIN, AFE4403_TIAGAIN_CAP, CAPACITANCE, afe4403_cap_table, ARRAY_SIZE(afe4403_cap_table));
260 
261 static AFE440X_ATTR(tia_resistance2, AFE4403_TIA_AMB_GAIN, AFE4403_TIAGAIN_RES, RESISTANCE, afe4403_res_table, ARRAY_SIZE(afe4403_res_table));
262 static AFE440X_ATTR(tia_capacitance2, AFE4403_TIA_AMB_GAIN, AFE4403_TIAGAIN_RES, CAPACITANCE, afe4403_cap_table, ARRAY_SIZE(afe4403_cap_table));
263 
264 static struct attribute *afe440x_attributes[] = {
265 	&afe440x_attr_tia_separate_en.dev_attr.attr,
266 	&afe440x_attr_tia_resistance1.dev_attr.attr,
267 	&afe440x_attr_tia_capacitance1.dev_attr.attr,
268 	&afe440x_attr_tia_resistance2.dev_attr.attr,
269 	&afe440x_attr_tia_capacitance2.dev_attr.attr,
270 	&dev_attr_tia_resistance_available.attr,
271 	&dev_attr_tia_capacitance_available.attr,
272 	NULL
273 };
274 
275 static const struct attribute_group afe440x_attribute_group = {
276 	.attrs = afe440x_attributes
277 };
278 
279 static int afe4403_read(struct afe4403_data *afe, unsigned int reg, u32 *val)
280 {
281 	u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
282 	u8 rx[3];
283 	int ret;
284 
285 	/* Enable reading from the device */
286 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
287 	if (ret)
288 		return ret;
289 
290 	ret = spi_write_then_read(afe->spi, &reg, 1, rx, 3);
291 	if (ret)
292 		return ret;
293 
294 	*val = (rx[0] << 16) |
295 		(rx[1] << 8) |
296 		(rx[2]);
297 
298 	/* Disable reading from the device */
299 	tx[3] = AFE440X_CONTROL0_WRITE;
300 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
301 	if (ret)
302 		return ret;
303 
304 	return 0;
305 }
306 
307 static int afe4403_read_raw(struct iio_dev *indio_dev,
308 			    struct iio_chan_spec const *chan,
309 			    int *val, int *val2, long mask)
310 {
311 	struct afe4403_data *afe = iio_priv(indio_dev);
312 	const struct afe440x_reg_info reg_info = afe4403_reg_info[chan->address];
313 	int ret;
314 
315 	switch (chan->type) {
316 	case IIO_INTENSITY:
317 		switch (mask) {
318 		case IIO_CHAN_INFO_RAW:
319 			ret = afe4403_read(afe, reg_info.reg, val);
320 			if (ret)
321 				return ret;
322 			return IIO_VAL_INT;
323 		case IIO_CHAN_INFO_OFFSET:
324 			ret = regmap_read(afe->regmap, reg_info.offreg,
325 					  val);
326 			if (ret)
327 				return ret;
328 			*val &= reg_info.mask;
329 			*val >>= reg_info.shift;
330 			return IIO_VAL_INT;
331 		}
332 		break;
333 	case IIO_CURRENT:
334 		switch (mask) {
335 		case IIO_CHAN_INFO_RAW:
336 			ret = regmap_read(afe->regmap, reg_info.reg, val);
337 			if (ret)
338 				return ret;
339 			*val &= reg_info.mask;
340 			*val >>= reg_info.shift;
341 			return IIO_VAL_INT;
342 		case IIO_CHAN_INFO_SCALE:
343 			*val = 0;
344 			*val2 = 800000;
345 			return IIO_VAL_INT_PLUS_MICRO;
346 		}
347 		break;
348 	default:
349 		break;
350 	}
351 
352 	return -EINVAL;
353 }
354 
355 static int afe4403_write_raw(struct iio_dev *indio_dev,
356 			     struct iio_chan_spec const *chan,
357 			     int val, int val2, long mask)
358 {
359 	struct afe4403_data *afe = iio_priv(indio_dev);
360 	const struct afe440x_reg_info reg_info = afe4403_reg_info[chan->address];
361 
362 	switch (chan->type) {
363 	case IIO_INTENSITY:
364 		switch (mask) {
365 		case IIO_CHAN_INFO_OFFSET:
366 			return regmap_update_bits(afe->regmap,
367 				reg_info.offreg,
368 				reg_info.mask,
369 				(val << reg_info.shift));
370 		}
371 		break;
372 	case IIO_CURRENT:
373 		switch (mask) {
374 		case IIO_CHAN_INFO_RAW:
375 			return regmap_update_bits(afe->regmap,
376 				reg_info.reg,
377 				reg_info.mask,
378 				(val << reg_info.shift));
379 		}
380 		break;
381 	default:
382 		break;
383 	}
384 
385 	return -EINVAL;
386 }
387 
388 static const struct iio_info afe4403_iio_info = {
389 	.attrs = &afe440x_attribute_group,
390 	.read_raw = afe4403_read_raw,
391 	.write_raw = afe4403_write_raw,
392 	.driver_module = THIS_MODULE,
393 };
394 
395 static irqreturn_t afe4403_trigger_handler(int irq, void *private)
396 {
397 	struct iio_poll_func *pf = private;
398 	struct iio_dev *indio_dev = pf->indio_dev;
399 	struct afe4403_data *afe = iio_priv(indio_dev);
400 	int ret, bit, i = 0;
401 	s32 buffer[8];
402 	u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
403 	u8 rx[3];
404 
405 	/* Enable reading from the device */
406 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
407 	if (ret)
408 		goto err;
409 
410 	for_each_set_bit(bit, indio_dev->active_scan_mask,
411 			 indio_dev->masklength) {
412 		ret = spi_write_then_read(afe->spi,
413 					  &afe4403_reg_info[bit].reg, 1,
414 					  rx, 3);
415 		if (ret)
416 			goto err;
417 
418 		buffer[i++] = (rx[0] << 16) |
419 				(rx[1] << 8) |
420 				(rx[2]);
421 	}
422 
423 	/* Disable reading from the device */
424 	tx[3] = AFE440X_CONTROL0_WRITE;
425 	ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
426 	if (ret)
427 		goto err;
428 
429 	iio_push_to_buffers_with_timestamp(indio_dev, buffer, pf->timestamp);
430 err:
431 	iio_trigger_notify_done(indio_dev->trig);
432 
433 	return IRQ_HANDLED;
434 }
435 
436 static const struct iio_trigger_ops afe4403_trigger_ops = {
437 	.owner = THIS_MODULE,
438 };
439 
440 #define AFE4403_TIMING_PAIRS			\
441 	{ AFE440X_LED2STC,	0x000050 },	\
442 	{ AFE440X_LED2ENDC,	0x0003e7 },	\
443 	{ AFE440X_LED1LEDSTC,	0x0007d0 },	\
444 	{ AFE440X_LED1LEDENDC,	0x000bb7 },	\
445 	{ AFE440X_ALED2STC,	0x000438 },	\
446 	{ AFE440X_ALED2ENDC,	0x0007cf },	\
447 	{ AFE440X_LED1STC,	0x000820 },	\
448 	{ AFE440X_LED1ENDC,	0x000bb7 },	\
449 	{ AFE440X_LED2LEDSTC,	0x000000 },	\
450 	{ AFE440X_LED2LEDENDC,	0x0003e7 },	\
451 	{ AFE440X_ALED1STC,	0x000c08 },	\
452 	{ AFE440X_ALED1ENDC,	0x000f9f },	\
453 	{ AFE440X_LED2CONVST,	0x0003ef },	\
454 	{ AFE440X_LED2CONVEND,	0x0007cf },	\
455 	{ AFE440X_ALED2CONVST,	0x0007d7 },	\
456 	{ AFE440X_ALED2CONVEND,	0x000bb7 },	\
457 	{ AFE440X_LED1CONVST,	0x000bbf },	\
458 	{ AFE440X_LED1CONVEND,	0x009c3f },	\
459 	{ AFE440X_ALED1CONVST,	0x000fa7 },	\
460 	{ AFE440X_ALED1CONVEND,	0x001387 },	\
461 	{ AFE440X_ADCRSTSTCT0,	0x0003e8 },	\
462 	{ AFE440X_ADCRSTENDCT0,	0x0003eb },	\
463 	{ AFE440X_ADCRSTSTCT1,	0x0007d0 },	\
464 	{ AFE440X_ADCRSTENDCT1,	0x0007d3 },	\
465 	{ AFE440X_ADCRSTSTCT2,	0x000bb8 },	\
466 	{ AFE440X_ADCRSTENDCT2,	0x000bbb },	\
467 	{ AFE440X_ADCRSTSTCT3,	0x000fa0 },	\
468 	{ AFE440X_ADCRSTENDCT3,	0x000fa3 },	\
469 	{ AFE440X_PRPCOUNT,	0x009c3f },	\
470 	{ AFE440X_PDNCYCLESTC,	0x001518 },	\
471 	{ AFE440X_PDNCYCLEENDC,	0x00991f }
472 
473 static const struct reg_sequence afe4403_reg_sequences[] = {
474 	AFE4403_TIMING_PAIRS,
475 	{ AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN | 0x000007},
476 	{ AFE4403_TIA_AMB_GAIN, AFE4403_TIAGAIN_RES_1_M },
477 	{ AFE440X_LEDCNTRL, (0x14 << AFE440X_LEDCNTRL_LED1_SHIFT) |
478 			    (0x14 << AFE440X_LEDCNTRL_LED2_SHIFT) },
479 	{ AFE440X_CONTROL2, AFE440X_CONTROL2_TX_REF_050 <<
480 			    AFE440X_CONTROL2_TX_REF_SHIFT },
481 };
482 
483 static const struct regmap_range afe4403_yes_ranges[] = {
484 	regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL),
485 };
486 
487 static const struct regmap_access_table afe4403_volatile_table = {
488 	.yes_ranges = afe4403_yes_ranges,
489 	.n_yes_ranges = ARRAY_SIZE(afe4403_yes_ranges),
490 };
491 
492 static const struct regmap_config afe4403_regmap_config = {
493 	.reg_bits = 8,
494 	.val_bits = 24,
495 
496 	.max_register = AFE440X_PDNCYCLEENDC,
497 	.cache_type = REGCACHE_RBTREE,
498 	.volatile_table = &afe4403_volatile_table,
499 };
500 
501 #ifdef CONFIG_OF
502 static const struct of_device_id afe4403_of_match[] = {
503 	{ .compatible = "ti,afe4403", },
504 	{ /* sentinel */ }
505 };
506 MODULE_DEVICE_TABLE(of, afe4403_of_match);
507 #endif
508 
509 static int __maybe_unused afe4403_suspend(struct device *dev)
510 {
511 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
512 	struct afe4403_data *afe = iio_priv(indio_dev);
513 	int ret;
514 
515 	ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
516 				 AFE440X_CONTROL2_PDN_AFE,
517 				 AFE440X_CONTROL2_PDN_AFE);
518 	if (ret)
519 		return ret;
520 
521 	ret = regulator_disable(afe->regulator);
522 	if (ret) {
523 		dev_err(dev, "Unable to disable regulator\n");
524 		return ret;
525 	}
526 
527 	return 0;
528 }
529 
530 static int __maybe_unused afe4403_resume(struct device *dev)
531 {
532 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
533 	struct afe4403_data *afe = iio_priv(indio_dev);
534 	int ret;
535 
536 	ret = regulator_enable(afe->regulator);
537 	if (ret) {
538 		dev_err(dev, "Unable to enable regulator\n");
539 		return ret;
540 	}
541 
542 	ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
543 				 AFE440X_CONTROL2_PDN_AFE, 0);
544 	if (ret)
545 		return ret;
546 
547 	return 0;
548 }
549 
550 static SIMPLE_DEV_PM_OPS(afe4403_pm_ops, afe4403_suspend, afe4403_resume);
551 
552 static int afe4403_probe(struct spi_device *spi)
553 {
554 	struct iio_dev *indio_dev;
555 	struct afe4403_data *afe;
556 	int ret;
557 
558 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*afe));
559 	if (!indio_dev)
560 		return -ENOMEM;
561 
562 	afe = iio_priv(indio_dev);
563 	spi_set_drvdata(spi, indio_dev);
564 
565 	afe->dev = &spi->dev;
566 	afe->spi = spi;
567 	afe->irq = spi->irq;
568 
569 	afe->regmap = devm_regmap_init_spi(spi, &afe4403_regmap_config);
570 	if (IS_ERR(afe->regmap)) {
571 		dev_err(afe->dev, "Unable to allocate register map\n");
572 		return PTR_ERR(afe->regmap);
573 	}
574 
575 	afe->regulator = devm_regulator_get(afe->dev, "tx_sup");
576 	if (IS_ERR(afe->regulator)) {
577 		dev_err(afe->dev, "Unable to get regulator\n");
578 		return PTR_ERR(afe->regulator);
579 	}
580 	ret = regulator_enable(afe->regulator);
581 	if (ret) {
582 		dev_err(afe->dev, "Unable to enable regulator\n");
583 		return ret;
584 	}
585 
586 	ret = regmap_write(afe->regmap, AFE440X_CONTROL0,
587 			   AFE440X_CONTROL0_SW_RESET);
588 	if (ret) {
589 		dev_err(afe->dev, "Unable to reset device\n");
590 		goto err_disable_reg;
591 	}
592 
593 	ret = regmap_multi_reg_write(afe->regmap, afe4403_reg_sequences,
594 				     ARRAY_SIZE(afe4403_reg_sequences));
595 	if (ret) {
596 		dev_err(afe->dev, "Unable to set register defaults\n");
597 		goto err_disable_reg;
598 	}
599 
600 	indio_dev->modes = INDIO_DIRECT_MODE;
601 	indio_dev->dev.parent = afe->dev;
602 	indio_dev->channels = afe4403_channels;
603 	indio_dev->num_channels = ARRAY_SIZE(afe4403_channels);
604 	indio_dev->name = AFE4403_DRIVER_NAME;
605 	indio_dev->info = &afe4403_iio_info;
606 
607 	if (afe->irq > 0) {
608 		afe->trig = devm_iio_trigger_alloc(afe->dev,
609 						   "%s-dev%d",
610 						   indio_dev->name,
611 						   indio_dev->id);
612 		if (!afe->trig) {
613 			dev_err(afe->dev, "Unable to allocate IIO trigger\n");
614 			ret = -ENOMEM;
615 			goto err_disable_reg;
616 		}
617 
618 		iio_trigger_set_drvdata(afe->trig, indio_dev);
619 
620 		afe->trig->ops = &afe4403_trigger_ops;
621 		afe->trig->dev.parent = afe->dev;
622 
623 		ret = iio_trigger_register(afe->trig);
624 		if (ret) {
625 			dev_err(afe->dev, "Unable to register IIO trigger\n");
626 			goto err_disable_reg;
627 		}
628 
629 		ret = devm_request_threaded_irq(afe->dev, afe->irq,
630 						iio_trigger_generic_data_rdy_poll,
631 						NULL, IRQF_ONESHOT,
632 						AFE4403_DRIVER_NAME,
633 						afe->trig);
634 		if (ret) {
635 			dev_err(afe->dev, "Unable to request IRQ\n");
636 			goto err_trig;
637 		}
638 	}
639 
640 	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
641 					 afe4403_trigger_handler, NULL);
642 	if (ret) {
643 		dev_err(afe->dev, "Unable to setup buffer\n");
644 		goto err_trig;
645 	}
646 
647 	ret = iio_device_register(indio_dev);
648 	if (ret) {
649 		dev_err(afe->dev, "Unable to register IIO device\n");
650 		goto err_buff;
651 	}
652 
653 	return 0;
654 
655 err_buff:
656 	iio_triggered_buffer_cleanup(indio_dev);
657 err_trig:
658 	if (afe->irq > 0)
659 		iio_trigger_unregister(afe->trig);
660 err_disable_reg:
661 	regulator_disable(afe->regulator);
662 
663 	return ret;
664 }
665 
666 static int afe4403_remove(struct spi_device *spi)
667 {
668 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
669 	struct afe4403_data *afe = iio_priv(indio_dev);
670 	int ret;
671 
672 	iio_device_unregister(indio_dev);
673 
674 	iio_triggered_buffer_cleanup(indio_dev);
675 
676 	if (afe->irq > 0)
677 		iio_trigger_unregister(afe->trig);
678 
679 	ret = regulator_disable(afe->regulator);
680 	if (ret) {
681 		dev_err(afe->dev, "Unable to disable regulator\n");
682 		return ret;
683 	}
684 
685 	return 0;
686 }
687 
688 static const struct spi_device_id afe4403_ids[] = {
689 	{ "afe4403", 0 },
690 	{ /* sentinel */ }
691 };
692 MODULE_DEVICE_TABLE(spi, afe4403_ids);
693 
694 static struct spi_driver afe4403_spi_driver = {
695 	.driver = {
696 		.name = AFE4403_DRIVER_NAME,
697 		.of_match_table = of_match_ptr(afe4403_of_match),
698 		.pm = &afe4403_pm_ops,
699 	},
700 	.probe = afe4403_probe,
701 	.remove = afe4403_remove,
702 	.id_table = afe4403_ids,
703 };
704 module_spi_driver(afe4403_spi_driver);
705 
706 MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
707 MODULE_DESCRIPTION("TI AFE4403 Heart Rate and Pulse Oximeter");
708 MODULE_LICENSE("GPL v2");
709