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14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/interrupt.h>
17#include <linux/delay.h>
18#include <linux/err.h>
19#include <linux/irq.h>
20#include <linux/i2c.h>
21#include <linux/mutex.h>
22#include <linux/mod_devicetable.h>
23#include <linux/regmap.h>
24#include <linux/iio/iio.h>
25#include <linux/iio/buffer.h>
26#include <linux/iio/kfifo_buf.h>
27
28#define MAX30102_REGMAP_NAME "max30102_regmap"
29#define MAX30102_DRV_NAME "max30102"
30#define MAX30102_PART_NUMBER 0x15
31
32enum max30102_chip_id {
33 max30102,
34 max30105,
35};
36
37enum max3012_led_idx {
38 MAX30102_LED_RED,
39 MAX30102_LED_IR,
40 MAX30105_LED_GREEN,
41};
42
43#define MAX30102_REG_INT_STATUS 0x00
44#define MAX30102_REG_INT_STATUS_PWR_RDY BIT(0)
45#define MAX30102_REG_INT_STATUS_PROX_INT BIT(4)
46#define MAX30102_REG_INT_STATUS_ALC_OVF BIT(5)
47#define MAX30102_REG_INT_STATUS_PPG_RDY BIT(6)
48#define MAX30102_REG_INT_STATUS_FIFO_RDY BIT(7)
49
50#define MAX30102_REG_INT_ENABLE 0x02
51#define MAX30102_REG_INT_ENABLE_PROX_INT_EN BIT(4)
52#define MAX30102_REG_INT_ENABLE_ALC_OVF_EN BIT(5)
53#define MAX30102_REG_INT_ENABLE_PPG_EN BIT(6)
54#define MAX30102_REG_INT_ENABLE_FIFO_EN BIT(7)
55#define MAX30102_REG_INT_ENABLE_MASK 0xf0
56#define MAX30102_REG_INT_ENABLE_MASK_SHIFT 4
57
58#define MAX30102_REG_FIFO_WR_PTR 0x04
59#define MAX30102_REG_FIFO_OVR_CTR 0x05
60#define MAX30102_REG_FIFO_RD_PTR 0x06
61#define MAX30102_REG_FIFO_DATA 0x07
62#define MAX30102_REG_FIFO_DATA_BYTES 3
63
64#define MAX30102_REG_FIFO_CONFIG 0x08
65#define MAX30102_REG_FIFO_CONFIG_AVG_4SAMPLES BIT(1)
66#define MAX30102_REG_FIFO_CONFIG_AVG_SHIFT 5
67#define MAX30102_REG_FIFO_CONFIG_AFULL BIT(0)
68
69#define MAX30102_REG_MODE_CONFIG 0x09
70#define MAX30102_REG_MODE_CONFIG_MODE_NONE 0x00
71#define MAX30102_REG_MODE_CONFIG_MODE_HR 0x02
72#define MAX30102_REG_MODE_CONFIG_MODE_HR_SPO2 0x03
73#define MAX30102_REG_MODE_CONFIG_MODE_MULTI 0x07
74#define MAX30102_REG_MODE_CONFIG_MODE_MASK GENMASK(2, 0)
75#define MAX30102_REG_MODE_CONFIG_PWR BIT(7)
76
77#define MAX30102_REG_MODE_CONTROL_SLOT21 0x11
78#define MAX30102_REG_MODE_CONTROL_SLOT43 0x12
79#define MAX30102_REG_MODE_CONTROL_SLOT_MASK (GENMASK(6, 4) | GENMASK(2, 0))
80#define MAX30102_REG_MODE_CONTROL_SLOT_SHIFT 4
81
82#define MAX30102_REG_SPO2_CONFIG 0x0a
83#define MAX30102_REG_SPO2_CONFIG_PULSE_411_US 0x03
84#define MAX30102_REG_SPO2_CONFIG_SR_400HZ 0x03
85#define MAX30102_REG_SPO2_CONFIG_SR_MASK 0x07
86#define MAX30102_REG_SPO2_CONFIG_SR_MASK_SHIFT 2
87#define MAX30102_REG_SPO2_CONFIG_ADC_4096_STEPS BIT(0)
88#define MAX30102_REG_SPO2_CONFIG_ADC_MASK_SHIFT 5
89
90#define MAX30102_REG_RED_LED_CONFIG 0x0c
91#define MAX30102_REG_IR_LED_CONFIG 0x0d
92#define MAX30105_REG_GREEN_LED_CONFIG 0x0e
93
94#define MAX30102_REG_TEMP_CONFIG 0x21
95#define MAX30102_REG_TEMP_CONFIG_TEMP_EN BIT(0)
96
97#define MAX30102_REG_TEMP_INTEGER 0x1f
98#define MAX30102_REG_TEMP_FRACTION 0x20
99
100#define MAX30102_REG_REV_ID 0xfe
101#define MAX30102_REG_PART_ID 0xff
102
103struct max30102_data {
104 struct i2c_client *client;
105 struct iio_dev *indio_dev;
106 struct mutex lock;
107 struct regmap *regmap;
108 enum max30102_chip_id chip_id;
109
110 u8 buffer[12];
111 __be32 processed_buffer[3];
112};
113
114static const struct regmap_config max30102_regmap_config = {
115 .name = MAX30102_REGMAP_NAME,
116
117 .reg_bits = 8,
118 .val_bits = 8,
119};
120
121static const unsigned long max30102_scan_masks[] = {
122 BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR),
123 0
124};
125
126static const unsigned long max30105_scan_masks[] = {
127 BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR),
128 BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR) |
129 BIT(MAX30105_LED_GREEN),
130 0
131};
132
133#define MAX30102_INTENSITY_CHANNEL(_si, _mod) { \
134 .type = IIO_INTENSITY, \
135 .channel2 = _mod, \
136 .modified = 1, \
137 .scan_index = _si, \
138 .scan_type = { \
139 .sign = 'u', \
140 .shift = 8, \
141 .realbits = 18, \
142 .storagebits = 32, \
143 .endianness = IIO_BE, \
144 }, \
145 }
146
147static const struct iio_chan_spec max30102_channels[] = {
148 MAX30102_INTENSITY_CHANNEL(MAX30102_LED_RED, IIO_MOD_LIGHT_RED),
149 MAX30102_INTENSITY_CHANNEL(MAX30102_LED_IR, IIO_MOD_LIGHT_IR),
150 {
151 .type = IIO_TEMP,
152 .info_mask_separate =
153 BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
154 .scan_index = -1,
155 },
156};
157
158static const struct iio_chan_spec max30105_channels[] = {
159 MAX30102_INTENSITY_CHANNEL(MAX30102_LED_RED, IIO_MOD_LIGHT_RED),
160 MAX30102_INTENSITY_CHANNEL(MAX30102_LED_IR, IIO_MOD_LIGHT_IR),
161 MAX30102_INTENSITY_CHANNEL(MAX30105_LED_GREEN, IIO_MOD_LIGHT_GREEN),
162 {
163 .type = IIO_TEMP,
164 .info_mask_separate =
165 BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
166 .scan_index = -1,
167 },
168};
169
170static int max30102_set_power(struct max30102_data *data, bool en)
171{
172 return regmap_update_bits(data->regmap, MAX30102_REG_MODE_CONFIG,
173 MAX30102_REG_MODE_CONFIG_PWR,
174 en ? 0 : MAX30102_REG_MODE_CONFIG_PWR);
175}
176
177static int max30102_set_powermode(struct max30102_data *data, u8 mode, bool en)
178{
179 u8 reg = mode;
180
181 if (!en)
182 reg |= MAX30102_REG_MODE_CONFIG_PWR;
183
184 return regmap_update_bits(data->regmap, MAX30102_REG_MODE_CONFIG,
185 MAX30102_REG_MODE_CONFIG_PWR |
186 MAX30102_REG_MODE_CONFIG_MODE_MASK, reg);
187}
188
189#define MAX30102_MODE_CONTROL_LED_SLOTS(slot2, slot1) \
190 ((slot2 << MAX30102_REG_MODE_CONTROL_SLOT_SHIFT) | slot1)
191
192static int max30102_buffer_postenable(struct iio_dev *indio_dev)
193{
194 struct max30102_data *data = iio_priv(indio_dev);
195 int ret;
196 u8 reg;
197
198 switch (*indio_dev->active_scan_mask) {
199 case BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR):
200 reg = MAX30102_REG_MODE_CONFIG_MODE_HR_SPO2;
201 break;
202 case BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR) |
203 BIT(MAX30105_LED_GREEN):
204 ret = regmap_update_bits(data->regmap,
205 MAX30102_REG_MODE_CONTROL_SLOT21,
206 MAX30102_REG_MODE_CONTROL_SLOT_MASK,
207 MAX30102_MODE_CONTROL_LED_SLOTS(2, 1));
208 if (ret)
209 return ret;
210
211 ret = regmap_update_bits(data->regmap,
212 MAX30102_REG_MODE_CONTROL_SLOT43,
213 MAX30102_REG_MODE_CONTROL_SLOT_MASK,
214 MAX30102_MODE_CONTROL_LED_SLOTS(0, 3));
215 if (ret)
216 return ret;
217
218 reg = MAX30102_REG_MODE_CONFIG_MODE_MULTI;
219 break;
220 default:
221 return -EINVAL;
222 }
223
224 return max30102_set_powermode(data, reg, true);
225}
226
227static int max30102_buffer_predisable(struct iio_dev *indio_dev)
228{
229 struct max30102_data *data = iio_priv(indio_dev);
230
231 return max30102_set_powermode(data, MAX30102_REG_MODE_CONFIG_MODE_NONE,
232 false);
233}
234
235static const struct iio_buffer_setup_ops max30102_buffer_setup_ops = {
236 .postenable = max30102_buffer_postenable,
237 .predisable = max30102_buffer_predisable,
238};
239
240static inline int max30102_fifo_count(struct max30102_data *data)
241{
242 unsigned int val;
243 int ret;
244
245 ret = regmap_read(data->regmap, MAX30102_REG_INT_STATUS, &val);
246 if (ret)
247 return ret;
248
249
250 if (val & MAX30102_REG_INT_STATUS_FIFO_RDY)
251 return 1;
252
253 return 0;
254}
255
256#define MAX30102_COPY_DATA(i) \
257 memcpy(&data->processed_buffer[(i)], \
258 &buffer[(i) * MAX30102_REG_FIFO_DATA_BYTES], \
259 MAX30102_REG_FIFO_DATA_BYTES)
260
261static int max30102_read_measurement(struct max30102_data *data,
262 unsigned int measurements)
263{
264 int ret;
265 u8 *buffer = (u8 *) &data->buffer;
266
267 ret = i2c_smbus_read_i2c_block_data(data->client,
268 MAX30102_REG_FIFO_DATA,
269 measurements *
270 MAX30102_REG_FIFO_DATA_BYTES,
271 buffer);
272
273 switch (measurements) {
274 case 3:
275 MAX30102_COPY_DATA(2);
276 fallthrough;
277 case 2:
278 MAX30102_COPY_DATA(1);
279 fallthrough;
280 case 1:
281 MAX30102_COPY_DATA(0);
282 break;
283 default:
284 return -EINVAL;
285 }
286
287 return (ret == measurements * MAX30102_REG_FIFO_DATA_BYTES) ?
288 0 : -EINVAL;
289}
290
291static irqreturn_t max30102_interrupt_handler(int irq, void *private)
292{
293 struct iio_dev *indio_dev = private;
294 struct max30102_data *data = iio_priv(indio_dev);
295 unsigned int measurements = bitmap_weight(indio_dev->active_scan_mask,
296 indio_dev->masklength);
297 int ret, cnt = 0;
298
299 mutex_lock(&data->lock);
300
301 while (cnt || (cnt = max30102_fifo_count(data)) > 0) {
302 ret = max30102_read_measurement(data, measurements);
303 if (ret)
304 break;
305
306 iio_push_to_buffers(data->indio_dev, data->processed_buffer);
307 cnt--;
308 }
309
310 mutex_unlock(&data->lock);
311
312 return IRQ_HANDLED;
313}
314
315static int max30102_get_current_idx(unsigned int val, int *reg)
316{
317
318 *reg = val / 200;
319
320 return *reg > 0xff ? -EINVAL : 0;
321}
322
323static int max30102_led_init(struct max30102_data *data)
324{
325 struct device *dev = &data->client->dev;
326 unsigned int val;
327 int reg, ret;
328
329 ret = device_property_read_u32(dev, "maxim,red-led-current-microamp", &val);
330 if (ret) {
331 dev_info(dev, "no red-led-current-microamp set\n");
332
333
334 val = 7000;
335 }
336
337 ret = max30102_get_current_idx(val, ®);
338 if (ret) {
339 dev_err(dev, "invalid RED LED current setting %d\n", val);
340 return ret;
341 }
342
343 ret = regmap_write(data->regmap, MAX30102_REG_RED_LED_CONFIG, reg);
344 if (ret)
345 return ret;
346
347 if (data->chip_id == max30105) {
348 ret = device_property_read_u32(dev,
349 "maxim,green-led-current-microamp", &val);
350 if (ret) {
351 dev_info(dev, "no green-led-current-microamp set\n");
352
353
354 val = 7000;
355 }
356
357 ret = max30102_get_current_idx(val, ®);
358 if (ret) {
359 dev_err(dev, "invalid green LED current setting %d\n",
360 val);
361 return ret;
362 }
363
364 ret = regmap_write(data->regmap, MAX30105_REG_GREEN_LED_CONFIG,
365 reg);
366 if (ret)
367 return ret;
368 }
369
370 ret = device_property_read_u32(dev, "maxim,ir-led-current-microamp", &val);
371 if (ret) {
372 dev_info(dev, "no ir-led-current-microamp set\n");
373
374
375 val = 7000;
376 }
377
378 ret = max30102_get_current_idx(val, ®);
379 if (ret) {
380 dev_err(dev, "invalid IR LED current setting %d\n", val);
381 return ret;
382 }
383
384 return regmap_write(data->regmap, MAX30102_REG_IR_LED_CONFIG, reg);
385}
386
387static int max30102_chip_init(struct max30102_data *data)
388{
389 int ret;
390
391
392 ret = max30102_led_init(data);
393 if (ret)
394 return ret;
395
396
397 ret = regmap_write(data->regmap, MAX30102_REG_SPO2_CONFIG,
398 (MAX30102_REG_SPO2_CONFIG_ADC_4096_STEPS
399 << MAX30102_REG_SPO2_CONFIG_ADC_MASK_SHIFT) |
400 (MAX30102_REG_SPO2_CONFIG_SR_400HZ
401 << MAX30102_REG_SPO2_CONFIG_SR_MASK_SHIFT) |
402 MAX30102_REG_SPO2_CONFIG_PULSE_411_US);
403 if (ret)
404 return ret;
405
406
407 ret = regmap_write(data->regmap, MAX30102_REG_FIFO_CONFIG,
408 (MAX30102_REG_FIFO_CONFIG_AVG_4SAMPLES
409 << MAX30102_REG_FIFO_CONFIG_AVG_SHIFT) |
410 MAX30102_REG_FIFO_CONFIG_AFULL);
411 if (ret)
412 return ret;
413
414
415 return regmap_update_bits(data->regmap, MAX30102_REG_INT_ENABLE,
416 MAX30102_REG_INT_ENABLE_MASK,
417 MAX30102_REG_INT_ENABLE_FIFO_EN);
418}
419
420static int max30102_read_temp(struct max30102_data *data, int *val)
421{
422 int ret;
423 unsigned int reg;
424
425 ret = regmap_read(data->regmap, MAX30102_REG_TEMP_INTEGER, ®);
426 if (ret < 0)
427 return ret;
428 *val = reg << 4;
429
430 ret = regmap_read(data->regmap, MAX30102_REG_TEMP_FRACTION, ®);
431 if (ret < 0)
432 return ret;
433
434 *val |= reg & 0xf;
435 *val = sign_extend32(*val, 11);
436
437 return 0;
438}
439
440static int max30102_get_temp(struct max30102_data *data, int *val, bool en)
441{
442 int ret;
443
444 if (en) {
445 ret = max30102_set_power(data, true);
446 if (ret)
447 return ret;
448 }
449
450
451 ret = regmap_update_bits(data->regmap, MAX30102_REG_TEMP_CONFIG,
452 MAX30102_REG_TEMP_CONFIG_TEMP_EN,
453 MAX30102_REG_TEMP_CONFIG_TEMP_EN);
454 if (ret)
455 goto out;
456
457 msleep(35);
458 ret = max30102_read_temp(data, val);
459
460out:
461 if (en)
462 max30102_set_power(data, false);
463
464 return ret;
465}
466
467static int max30102_read_raw(struct iio_dev *indio_dev,
468 struct iio_chan_spec const *chan,
469 int *val, int *val2, long mask)
470{
471 struct max30102_data *data = iio_priv(indio_dev);
472 int ret = -EINVAL;
473
474 switch (mask) {
475 case IIO_CHAN_INFO_RAW:
476
477
478
479
480 mutex_lock(&indio_dev->mlock);
481 if (!iio_buffer_enabled(indio_dev))
482 ret = max30102_get_temp(data, val, true);
483 else
484 ret = max30102_get_temp(data, val, false);
485 mutex_unlock(&indio_dev->mlock);
486 if (ret)
487 return ret;
488
489 ret = IIO_VAL_INT;
490 break;
491 case IIO_CHAN_INFO_SCALE:
492 *val = 1000;
493 *val2 = 16;
494 ret = IIO_VAL_FRACTIONAL;
495 break;
496 }
497
498 return ret;
499}
500
501static const struct iio_info max30102_info = {
502 .read_raw = max30102_read_raw,
503};
504
505static int max30102_probe(struct i2c_client *client,
506 const struct i2c_device_id *id)
507{
508 struct max30102_data *data;
509 struct iio_buffer *buffer;
510 struct iio_dev *indio_dev;
511 int ret;
512 unsigned int reg;
513
514 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
515 if (!indio_dev)
516 return -ENOMEM;
517
518 buffer = devm_iio_kfifo_allocate(&client->dev);
519 if (!buffer)
520 return -ENOMEM;
521
522 iio_device_attach_buffer(indio_dev, buffer);
523
524 indio_dev->name = MAX30102_DRV_NAME;
525 indio_dev->info = &max30102_info;
526 indio_dev->modes = (INDIO_BUFFER_SOFTWARE | INDIO_DIRECT_MODE);
527 indio_dev->setup_ops = &max30102_buffer_setup_ops;
528
529 data = iio_priv(indio_dev);
530 data->indio_dev = indio_dev;
531 data->client = client;
532 data->chip_id = id->driver_data;
533
534 mutex_init(&data->lock);
535 i2c_set_clientdata(client, indio_dev);
536
537 switch (data->chip_id) {
538 case max30105:
539 indio_dev->channels = max30105_channels;
540 indio_dev->num_channels = ARRAY_SIZE(max30105_channels);
541 indio_dev->available_scan_masks = max30105_scan_masks;
542 break;
543 case max30102:
544 indio_dev->channels = max30102_channels;
545 indio_dev->num_channels = ARRAY_SIZE(max30102_channels);
546 indio_dev->available_scan_masks = max30102_scan_masks;
547 break;
548 default:
549 return -ENODEV;
550 }
551
552 data->regmap = devm_regmap_init_i2c(client, &max30102_regmap_config);
553 if (IS_ERR(data->regmap)) {
554 dev_err(&client->dev, "regmap initialization failed\n");
555 return PTR_ERR(data->regmap);
556 }
557
558
559 ret = regmap_read(data->regmap, MAX30102_REG_PART_ID, ®);
560 if (ret)
561 return ret;
562 if (reg != MAX30102_PART_NUMBER)
563 return -ENODEV;
564
565
566 ret = regmap_read(data->regmap, MAX30102_REG_REV_ID, ®);
567 if (ret)
568 return ret;
569 dev_dbg(&client->dev, "max3010x revision %02x\n", reg);
570
571
572 ret = max30102_set_powermode(data, MAX30102_REG_MODE_CONFIG_MODE_NONE,
573 false);
574 if (ret)
575 return ret;
576
577 ret = max30102_chip_init(data);
578 if (ret)
579 return ret;
580
581 if (client->irq <= 0) {
582 dev_err(&client->dev, "no valid irq defined\n");
583 return -EINVAL;
584 }
585
586 ret = devm_request_threaded_irq(&client->dev, client->irq,
587 NULL, max30102_interrupt_handler,
588 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
589 "max30102_irq", indio_dev);
590 if (ret) {
591 dev_err(&client->dev, "request irq (%d) failed\n", client->irq);
592 return ret;
593 }
594
595 return iio_device_register(indio_dev);
596}
597
598static int max30102_remove(struct i2c_client *client)
599{
600 struct iio_dev *indio_dev = i2c_get_clientdata(client);
601 struct max30102_data *data = iio_priv(indio_dev);
602
603 iio_device_unregister(indio_dev);
604 max30102_set_power(data, false);
605
606 return 0;
607}
608
609static const struct i2c_device_id max30102_id[] = {
610 { "max30102", max30102 },
611 { "max30105", max30105 },
612 {}
613};
614MODULE_DEVICE_TABLE(i2c, max30102_id);
615
616static const struct of_device_id max30102_dt_ids[] = {
617 { .compatible = "maxim,max30102" },
618 { .compatible = "maxim,max30105" },
619 { }
620};
621MODULE_DEVICE_TABLE(of, max30102_dt_ids);
622
623static struct i2c_driver max30102_driver = {
624 .driver = {
625 .name = MAX30102_DRV_NAME,
626 .of_match_table = max30102_dt_ids,
627 },
628 .probe = max30102_probe,
629 .remove = max30102_remove,
630 .id_table = max30102_id,
631};
632module_i2c_driver(max30102_driver);
633
634MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");
635MODULE_DESCRIPTION("MAX30102 heart rate/pulse oximeter and MAX30105 particle sensor driver");
636MODULE_LICENSE("GPL");
637
