GNU Linux-libre 6.9.1-gnu
[releases.git] / drivers / iio / health / afe4403.c
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
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
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
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
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
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
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 static void afe4403_regulator_disable(void *data)
350 {
351         struct regulator *regulator = data;
352
353         regulator_disable(regulator);
354 }
355
356 #define AFE4403_TIMING_PAIRS                    \
357         { AFE440X_LED2STC,      0x000050 },     \
358         { AFE440X_LED2ENDC,     0x0003e7 },     \
359         { AFE440X_LED1LEDSTC,   0x0007d0 },     \
360         { AFE440X_LED1LEDENDC,  0x000bb7 },     \
361         { AFE440X_ALED2STC,     0x000438 },     \
362         { AFE440X_ALED2ENDC,    0x0007cf },     \
363         { AFE440X_LED1STC,      0x000820 },     \
364         { AFE440X_LED1ENDC,     0x000bb7 },     \
365         { AFE440X_LED2LEDSTC,   0x000000 },     \
366         { AFE440X_LED2LEDENDC,  0x0003e7 },     \
367         { AFE440X_ALED1STC,     0x000c08 },     \
368         { AFE440X_ALED1ENDC,    0x000f9f },     \
369         { AFE440X_LED2CONVST,   0x0003ef },     \
370         { AFE440X_LED2CONVEND,  0x0007cf },     \
371         { AFE440X_ALED2CONVST,  0x0007d7 },     \
372         { AFE440X_ALED2CONVEND, 0x000bb7 },     \
373         { AFE440X_LED1CONVST,   0x000bbf },     \
374         { AFE440X_LED1CONVEND,  0x009c3f },     \
375         { AFE440X_ALED1CONVST,  0x000fa7 },     \
376         { AFE440X_ALED1CONVEND, 0x001387 },     \
377         { AFE440X_ADCRSTSTCT0,  0x0003e8 },     \
378         { AFE440X_ADCRSTENDCT0, 0x0003eb },     \
379         { AFE440X_ADCRSTSTCT1,  0x0007d0 },     \
380         { AFE440X_ADCRSTENDCT1, 0x0007d3 },     \
381         { AFE440X_ADCRSTSTCT2,  0x000bb8 },     \
382         { AFE440X_ADCRSTENDCT2, 0x000bbb },     \
383         { AFE440X_ADCRSTSTCT3,  0x000fa0 },     \
384         { AFE440X_ADCRSTENDCT3, 0x000fa3 },     \
385         { AFE440X_PRPCOUNT,     0x009c3f },     \
386         { AFE440X_PDNCYCLESTC,  0x001518 },     \
387         { AFE440X_PDNCYCLEENDC, 0x00991f }
388
389 static const struct reg_sequence afe4403_reg_sequences[] = {
390         AFE4403_TIMING_PAIRS,
391         { AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN },
392         { AFE4403_TIAGAIN, AFE440X_TIAGAIN_ENSEPGAIN },
393 };
394
395 static const struct regmap_range afe4403_yes_ranges[] = {
396         regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL),
397 };
398
399 static const struct regmap_access_table afe4403_volatile_table = {
400         .yes_ranges = afe4403_yes_ranges,
401         .n_yes_ranges = ARRAY_SIZE(afe4403_yes_ranges),
402 };
403
404 static const struct regmap_config afe4403_regmap_config = {
405         .reg_bits = 8,
406         .val_bits = 24,
407
408         .max_register = AFE440X_PDNCYCLEENDC,
409         .cache_type = REGCACHE_RBTREE,
410         .volatile_table = &afe4403_volatile_table,
411 };
412
413 static const struct of_device_id afe4403_of_match[] = {
414         { .compatible = "ti,afe4403", },
415         { /* sentinel */ }
416 };
417 MODULE_DEVICE_TABLE(of, afe4403_of_match);
418
419 static int afe4403_suspend(struct device *dev)
420 {
421         struct iio_dev *indio_dev = spi_get_drvdata(to_spi_device(dev));
422         struct afe4403_data *afe = iio_priv(indio_dev);
423         int ret;
424
425         ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
426                                  AFE440X_CONTROL2_PDN_AFE,
427                                  AFE440X_CONTROL2_PDN_AFE);
428         if (ret)
429                 return ret;
430
431         ret = regulator_disable(afe->regulator);
432         if (ret) {
433                 dev_err(dev, "Unable to disable regulator\n");
434                 return ret;
435         }
436
437         return 0;
438 }
439
440 static int afe4403_resume(struct device *dev)
441 {
442         struct iio_dev *indio_dev = spi_get_drvdata(to_spi_device(dev));
443         struct afe4403_data *afe = iio_priv(indio_dev);
444         int ret;
445
446         ret = regulator_enable(afe->regulator);
447         if (ret) {
448                 dev_err(dev, "Unable to enable regulator\n");
449                 return ret;
450         }
451
452         ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
453                                  AFE440X_CONTROL2_PDN_AFE, 0);
454         if (ret)
455                 return ret;
456
457         return 0;
458 }
459
460 static DEFINE_SIMPLE_DEV_PM_OPS(afe4403_pm_ops, afe4403_suspend,
461                                 afe4403_resume);
462
463 static int afe4403_probe(struct spi_device *spi)
464 {
465         struct iio_dev *indio_dev;
466         struct afe4403_data *afe;
467         int i, ret;
468
469         indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*afe));
470         if (!indio_dev)
471                 return -ENOMEM;
472
473         afe = iio_priv(indio_dev);
474         spi_set_drvdata(spi, indio_dev);
475
476         afe->dev = &spi->dev;
477         afe->spi = spi;
478         afe->irq = spi->irq;
479
480         afe->regmap = devm_regmap_init_spi(spi, &afe4403_regmap_config);
481         if (IS_ERR(afe->regmap)) {
482                 dev_err(afe->dev, "Unable to allocate register map\n");
483                 return PTR_ERR(afe->regmap);
484         }
485
486         for (i = 0; i < F_MAX_FIELDS; i++) {
487                 afe->fields[i] = devm_regmap_field_alloc(afe->dev, afe->regmap,
488                                                          afe4403_reg_fields[i]);
489                 if (IS_ERR(afe->fields[i])) {
490                         dev_err(afe->dev, "Unable to allocate regmap fields\n");
491                         return PTR_ERR(afe->fields[i]);
492                 }
493         }
494
495         afe->regulator = devm_regulator_get(afe->dev, "tx_sup");
496         if (IS_ERR(afe->regulator))
497                 return dev_err_probe(afe->dev, PTR_ERR(afe->regulator),
498                                      "Unable to get regulator\n");
499
500         ret = regulator_enable(afe->regulator);
501         if (ret) {
502                 dev_err(afe->dev, "Unable to enable regulator\n");
503                 return ret;
504         }
505         ret = devm_add_action_or_reset(afe->dev, afe4403_regulator_disable, afe->regulator);
506         if (ret) {
507                 dev_err(afe->dev, "Unable to add regulator disable action\n");
508                 return ret;
509         }
510
511         ret = regmap_write(afe->regmap, AFE440X_CONTROL0,
512                            AFE440X_CONTROL0_SW_RESET);
513         if (ret) {
514                 dev_err(afe->dev, "Unable to reset device\n");
515                 return ret;
516         }
517
518         ret = regmap_multi_reg_write(afe->regmap, afe4403_reg_sequences,
519                                      ARRAY_SIZE(afe4403_reg_sequences));
520         if (ret) {
521                 dev_err(afe->dev, "Unable to set register defaults\n");
522                 return ret;
523         }
524
525         indio_dev->modes = INDIO_DIRECT_MODE;
526         indio_dev->channels = afe4403_channels;
527         indio_dev->num_channels = ARRAY_SIZE(afe4403_channels);
528         indio_dev->name = AFE4403_DRIVER_NAME;
529         indio_dev->info = &afe4403_iio_info;
530
531         if (afe->irq > 0) {
532                 afe->trig = devm_iio_trigger_alloc(afe->dev,
533                                                    "%s-dev%d",
534                                                    indio_dev->name,
535                                                    iio_device_id(indio_dev));
536                 if (!afe->trig) {
537                         dev_err(afe->dev, "Unable to allocate IIO trigger\n");
538                         return -ENOMEM;
539                 }
540
541                 iio_trigger_set_drvdata(afe->trig, indio_dev);
542
543                 ret = devm_iio_trigger_register(afe->dev, afe->trig);
544                 if (ret) {
545                         dev_err(afe->dev, "Unable to register IIO trigger\n");
546                         return ret;
547                 }
548
549                 ret = devm_request_threaded_irq(afe->dev, afe->irq,
550                                                 iio_trigger_generic_data_rdy_poll,
551                                                 NULL, IRQF_ONESHOT,
552                                                 AFE4403_DRIVER_NAME,
553                                                 afe->trig);
554                 if (ret) {
555                         dev_err(afe->dev, "Unable to request IRQ\n");
556                         return ret;
557                 }
558         }
559
560         ret = devm_iio_triggered_buffer_setup(afe->dev, indio_dev,
561                                               &iio_pollfunc_store_time,
562                                               afe4403_trigger_handler, NULL);
563         if (ret) {
564                 dev_err(afe->dev, "Unable to setup buffer\n");
565                 return ret;
566         }
567
568         ret = devm_iio_device_register(afe->dev, indio_dev);
569         if (ret) {
570                 dev_err(afe->dev, "Unable to register IIO device\n");
571                 return ret;
572         }
573
574         return 0;
575 }
576
577 static const struct spi_device_id afe4403_ids[] = {
578         { "afe4403", 0 },
579         { /* sentinel */ }
580 };
581 MODULE_DEVICE_TABLE(spi, afe4403_ids);
582
583 static struct spi_driver afe4403_spi_driver = {
584         .driver = {
585                 .name = AFE4403_DRIVER_NAME,
586                 .of_match_table = afe4403_of_match,
587                 .pm = pm_sleep_ptr(&afe4403_pm_ops),
588         },
589         .probe = afe4403_probe,
590         .id_table = afe4403_ids,
591 };
592 module_spi_driver(afe4403_spi_driver);
593
594 MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
595 MODULE_DESCRIPTION("TI AFE4403 Heart Rate Monitor and Pulse Oximeter AFE");
596 MODULE_LICENSE("GPL v2");