1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2014 Intel Corporation
4 *
5 * Driver for Semtech's SX9500 capacitive proximity/button solution.
6 * Datasheet available at
7 * <http://www.semtech.com/images/datasheet/sx9500.pdf>.
8 */
9
10#include <linux/kernel.h>
11#include <linux/slab.h>
12#include <linux/module.h>
13#include <linux/i2c.h>
14#include <linux/irq.h>
15#include <linux/acpi.h>
16#include <linux/gpio/consumer.h>
17#include <linux/regmap.h>
18#include <linux/pm.h>
19#include <linux/delay.h>
20
21#include <linux/iio/iio.h>
22#include <linux/iio/buffer.h>
23#include <linux/iio/sysfs.h>
24#include <linux/iio/events.h>
25#include <linux/iio/trigger.h>
26#include <linux/iio/triggered_buffer.h>
27#include <linux/iio/trigger_consumer.h>
28
29#define SX9500_DRIVER_NAME "sx9500"
30#define SX9500_IRQ_NAME "sx9500_event"
31
32/* Register definitions. */
33#define SX9500_REG_IRQ_SRC 0x00
34#define SX9500_REG_STAT 0x01
35#define SX9500_REG_IRQ_MSK 0x03
36
37#define SX9500_REG_PROX_CTRL0 0x06
38#define SX9500_REG_PROX_CTRL1 0x07
39#define SX9500_REG_PROX_CTRL2 0x08
40#define SX9500_REG_PROX_CTRL3 0x09
41#define SX9500_REG_PROX_CTRL4 0x0a
42#define SX9500_REG_PROX_CTRL5 0x0b
43#define SX9500_REG_PROX_CTRL6 0x0c
44#define SX9500_REG_PROX_CTRL7 0x0d
45#define SX9500_REG_PROX_CTRL8 0x0e
46
47#define SX9500_REG_SENSOR_SEL 0x20
48#define SX9500_REG_USE_MSB 0x21
49#define SX9500_REG_USE_LSB 0x22
50#define SX9500_REG_AVG_MSB 0x23
51#define SX9500_REG_AVG_LSB 0x24
52#define SX9500_REG_DIFF_MSB 0x25
53#define SX9500_REG_DIFF_LSB 0x26
54#define SX9500_REG_OFFSET_MSB 0x27
55#define SX9500_REG_OFFSET_LSB 0x28
56
57#define SX9500_REG_RESET 0x7f
58
59/* Write this to REG_RESET to do a soft reset. */
60#define SX9500_SOFT_RESET 0xde
61
62#define SX9500_SCAN_PERIOD_MASK GENMASK(6, 4)
63#define SX9500_SCAN_PERIOD_SHIFT 4
64
65/*
66 * These serve for identifying IRQ source in the IRQ_SRC register, and
67 * also for masking the IRQs in the IRQ_MSK register.
68 */
69#define SX9500_CLOSE_IRQ BIT(6)
70#define SX9500_FAR_IRQ BIT(5)
71#define SX9500_CONVDONE_IRQ BIT(3)
72
73#define SX9500_PROXSTAT_SHIFT 4
74#define SX9500_COMPSTAT_MASK GENMASK(3, 0)
75
76#define SX9500_NUM_CHANNELS 4
77#define SX9500_CHAN_MASK GENMASK(SX9500_NUM_CHANNELS - 1, 0)
78
79struct sx9500_data {
80 struct mutex mutex;
81 struct i2c_client *client;
82 struct iio_trigger *trig;
83 struct regmap *regmap;
84 struct gpio_desc *gpiod_rst;
85 /*
86 * Last reading of the proximity status for each channel. We
87 * only send an event to user space when this changes.
88 */
89 bool prox_stat[SX9500_NUM_CHANNELS];
90 bool event_enabled[SX9500_NUM_CHANNELS];
91 bool trigger_enabled;
92 u16 *buffer;
93 /* Remember enabled channels and sample rate during suspend. */
94 unsigned int suspend_ctrl0;
95 struct completion completion;
96 int data_rdy_users, close_far_users;
97 int channel_users[SX9500_NUM_CHANNELS];
98};
99
100static const struct iio_event_spec sx9500_events[] = {
101 {
102 .type = IIO_EV_TYPE_THRESH,
103 .dir = IIO_EV_DIR_EITHER,
104 .mask_separate = BIT(IIO_EV_INFO_ENABLE),
105 },
106};
107
108#define SX9500_CHANNEL(idx) \
109 { \
110 .type = IIO_PROXIMITY, \
111 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
112 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
113 .indexed = 1, \
114 .channel = idx, \
115 .event_spec = sx9500_events, \
116 .num_event_specs = ARRAY_SIZE(sx9500_events), \
117 .scan_index = idx, \
118 .scan_type = { \
119 .sign = 'u', \
120 .realbits = 16, \
121 .storagebits = 16, \
122 .shift = 0, \
123 }, \
124 }
125
126static const struct iio_chan_spec sx9500_channels[] = {
127 SX9500_CHANNEL(0),
128 SX9500_CHANNEL(1),
129 SX9500_CHANNEL(2),
130 SX9500_CHANNEL(3),
131 IIO_CHAN_SOFT_TIMESTAMP(4),
132};
133
134static const struct {
135 int val;
136 int val2;
137} sx9500_samp_freq_table[] = {
138 {33, 333333},
139 {16, 666666},
140 {11, 111111},
141 {8, 333333},
142 {6, 666666},
143 {5, 0},
144 {3, 333333},
145 {2, 500000},
146};
147
148static const unsigned int sx9500_scan_period_table[] = {
149 30, 60, 90, 120, 150, 200, 300, 400,
150};
151
152static const struct regmap_range sx9500_writable_reg_ranges[] = {
153 regmap_reg_range(SX9500_REG_IRQ_MSK, SX9500_REG_IRQ_MSK),
154 regmap_reg_range(SX9500_REG_PROX_CTRL0, SX9500_REG_PROX_CTRL8),
155 regmap_reg_range(SX9500_REG_SENSOR_SEL, SX9500_REG_SENSOR_SEL),
156 regmap_reg_range(SX9500_REG_OFFSET_MSB, SX9500_REG_OFFSET_LSB),
157 regmap_reg_range(SX9500_REG_RESET, SX9500_REG_RESET),
158};
159
160static const struct regmap_access_table sx9500_writeable_regs = {
161 .yes_ranges = sx9500_writable_reg_ranges,
162 .n_yes_ranges = ARRAY_SIZE(sx9500_writable_reg_ranges),
163};
164
165/*
166 * All allocated registers are readable, so we just list unallocated
167 * ones.
168 */
169static const struct regmap_range sx9500_non_readable_reg_ranges[] = {
170 regmap_reg_range(SX9500_REG_STAT + 1, SX9500_REG_STAT + 1),
171 regmap_reg_range(SX9500_REG_IRQ_MSK + 1, SX9500_REG_PROX_CTRL0 - 1),
172 regmap_reg_range(SX9500_REG_PROX_CTRL8 + 1, SX9500_REG_SENSOR_SEL - 1),
173 regmap_reg_range(SX9500_REG_OFFSET_LSB + 1, SX9500_REG_RESET - 1),
174};
175
176static const struct regmap_access_table sx9500_readable_regs = {
177 .no_ranges = sx9500_non_readable_reg_ranges,
178 .n_no_ranges = ARRAY_SIZE(sx9500_non_readable_reg_ranges),
179};
180
181static const struct regmap_range sx9500_volatile_reg_ranges[] = {
182 regmap_reg_range(SX9500_REG_IRQ_SRC, SX9500_REG_STAT),
183 regmap_reg_range(SX9500_REG_USE_MSB, SX9500_REG_OFFSET_LSB),
184 regmap_reg_range(SX9500_REG_RESET, SX9500_REG_RESET),
185};
186
187static const struct regmap_access_table sx9500_volatile_regs = {
188 .yes_ranges = sx9500_volatile_reg_ranges,
189 .n_yes_ranges = ARRAY_SIZE(sx9500_volatile_reg_ranges),
190};
191
192static const struct regmap_config sx9500_regmap_config = {
193 .reg_bits = 8,
194 .val_bits = 8,
195
196 .max_register = SX9500_REG_RESET,
197 .cache_type = REGCACHE_RBTREE,
198
199 .wr_table = &sx9500_writeable_regs,
200 .rd_table = &sx9500_readable_regs,
201 .volatile_table = &sx9500_volatile_regs,
202};
203
204static int sx9500_inc_users(struct sx9500_data *data, int *counter,
205 unsigned int reg, unsigned int bitmask)
206{
207 (*counter)++;
208 if (*counter != 1)
209 /* Bit is already active, nothing to do. */
210 return 0;
211
212 return regmap_update_bits(map: data->regmap, reg, mask: bitmask, val: bitmask);
213}
214
215static int sx9500_dec_users(struct sx9500_data *data, int *counter,
216 unsigned int reg, unsigned int bitmask)
217{
218 (*counter)--;
219 if (*counter != 0)
220 /* There are more users, do not deactivate. */
221 return 0;
222
223 return regmap_update_bits(map: data->regmap, reg, mask: bitmask, val: 0);
224}
225
226static int sx9500_inc_chan_users(struct sx9500_data *data, int chan)
227{
228 return sx9500_inc_users(data, counter: &data->channel_users[chan],
229 SX9500_REG_PROX_CTRL0, BIT(chan));
230}
231
232static int sx9500_dec_chan_users(struct sx9500_data *data, int chan)
233{
234 return sx9500_dec_users(data, counter: &data->channel_users[chan],
235 SX9500_REG_PROX_CTRL0, BIT(chan));
236}
237
238static int sx9500_inc_data_rdy_users(struct sx9500_data *data)
239{
240 return sx9500_inc_users(data, counter: &data->data_rdy_users,
241 SX9500_REG_IRQ_MSK, SX9500_CONVDONE_IRQ);
242}
243
244static int sx9500_dec_data_rdy_users(struct sx9500_data *data)
245{
246 return sx9500_dec_users(data, counter: &data->data_rdy_users,
247 SX9500_REG_IRQ_MSK, SX9500_CONVDONE_IRQ);
248}
249
250static int sx9500_inc_close_far_users(struct sx9500_data *data)
251{
252 return sx9500_inc_users(data, counter: &data->close_far_users,
253 SX9500_REG_IRQ_MSK,
254 SX9500_CLOSE_IRQ | SX9500_FAR_IRQ);
255}
256
257static int sx9500_dec_close_far_users(struct sx9500_data *data)
258{
259 return sx9500_dec_users(data, counter: &data->close_far_users,
260 SX9500_REG_IRQ_MSK,
261 SX9500_CLOSE_IRQ | SX9500_FAR_IRQ);
262}
263
264static int sx9500_read_prox_data(struct sx9500_data *data,
265 const struct iio_chan_spec *chan,
266 int *val)
267{
268 int ret;
269 __be16 regval;
270
271 ret = regmap_write(map: data->regmap, SX9500_REG_SENSOR_SEL, val: chan->channel);
272 if (ret < 0)
273 return ret;
274
275 ret = regmap_bulk_read(map: data->regmap, SX9500_REG_USE_MSB, val: &regval, val_count: 2);
276 if (ret < 0)
277 return ret;
278
279 *val = be16_to_cpu(regval);
280
281 return IIO_VAL_INT;
282}
283
284/*
285 * If we have no interrupt support, we have to wait for a scan period
286 * after enabling a channel to get a result.
287 */
288static int sx9500_wait_for_sample(struct sx9500_data *data)
289{
290 int ret;
291 unsigned int val;
292
293 ret = regmap_read(map: data->regmap, SX9500_REG_PROX_CTRL0, val: &val);
294 if (ret < 0)
295 return ret;
296
297 val = (val & SX9500_SCAN_PERIOD_MASK) >> SX9500_SCAN_PERIOD_SHIFT;
298
299 msleep(msecs: sx9500_scan_period_table[val]);
300
301 return 0;
302}
303
304static int sx9500_read_proximity(struct sx9500_data *data,
305 const struct iio_chan_spec *chan,
306 int *val)
307{
308 int ret;
309
310 mutex_lock(&data->mutex);
311
312 ret = sx9500_inc_chan_users(data, chan: chan->channel);
313 if (ret < 0)
314 goto out;
315
316 ret = sx9500_inc_data_rdy_users(data);
317 if (ret < 0)
318 goto out_dec_chan;
319
320 mutex_unlock(lock: &data->mutex);
321
322 if (data->client->irq > 0)
323 ret = wait_for_completion_interruptible(x: &data->completion);
324 else
325 ret = sx9500_wait_for_sample(data);
326
327 mutex_lock(&data->mutex);
328
329 if (ret < 0)
330 goto out_dec_data_rdy;
331
332 ret = sx9500_read_prox_data(data, chan, val);
333 if (ret < 0)
334 goto out_dec_data_rdy;
335
336 ret = sx9500_dec_data_rdy_users(data);
337 if (ret < 0)
338 goto out_dec_chan;
339
340 ret = sx9500_dec_chan_users(data, chan: chan->channel);
341 if (ret < 0)
342 goto out;
343
344 ret = IIO_VAL_INT;
345
346 goto out;
347
348out_dec_data_rdy:
349 sx9500_dec_data_rdy_users(data);
350out_dec_chan:
351 sx9500_dec_chan_users(data, chan: chan->channel);
352out:
353 mutex_unlock(lock: &data->mutex);
354 reinit_completion(x: &data->completion);
355
356 return ret;
357}
358
359static int sx9500_read_samp_freq(struct sx9500_data *data,
360 int *val, int *val2)
361{
362 int ret;
363 unsigned int regval;
364
365 mutex_lock(&data->mutex);
366 ret = regmap_read(map: data->regmap, SX9500_REG_PROX_CTRL0, val: &regval);
367 mutex_unlock(lock: &data->mutex);
368
369 if (ret < 0)
370 return ret;
371
372 regval = (regval & SX9500_SCAN_PERIOD_MASK) >> SX9500_SCAN_PERIOD_SHIFT;
373 *val = sx9500_samp_freq_table[regval].val;
374 *val2 = sx9500_samp_freq_table[regval].val2;
375
376 return IIO_VAL_INT_PLUS_MICRO;
377}
378
379static int sx9500_read_raw(struct iio_dev *indio_dev,
380 const struct iio_chan_spec *chan,
381 int *val, int *val2, long mask)
382{
383 struct sx9500_data *data = iio_priv(indio_dev);
384 int ret;
385
386 switch (chan->type) {
387 case IIO_PROXIMITY:
388 switch (mask) {
389 case IIO_CHAN_INFO_RAW:
390 ret = iio_device_claim_direct_mode(indio_dev);
391 if (ret)
392 return ret;
393 ret = sx9500_read_proximity(data, chan, val);
394 iio_device_release_direct_mode(indio_dev);
395 return ret;
396 case IIO_CHAN_INFO_SAMP_FREQ:
397 return sx9500_read_samp_freq(data, val, val2);
398 default:
399 return -EINVAL;
400 }
401 default:
402 return -EINVAL;
403 }
404}
405
406static int sx9500_set_samp_freq(struct sx9500_data *data,
407 int val, int val2)
408{
409 int i, ret;
410
411 for (i = 0; i < ARRAY_SIZE(sx9500_samp_freq_table); i++)
412 if (val == sx9500_samp_freq_table[i].val &&
413 val2 == sx9500_samp_freq_table[i].val2)
414 break;
415
416 if (i == ARRAY_SIZE(sx9500_samp_freq_table))
417 return -EINVAL;
418
419 mutex_lock(&data->mutex);
420
421 ret = regmap_update_bits(map: data->regmap, SX9500_REG_PROX_CTRL0,
422 SX9500_SCAN_PERIOD_MASK,
423 val: i << SX9500_SCAN_PERIOD_SHIFT);
424
425 mutex_unlock(lock: &data->mutex);
426
427 return ret;
428}
429
430static int sx9500_write_raw(struct iio_dev *indio_dev,
431 const struct iio_chan_spec *chan,
432 int val, int val2, long mask)
433{
434 struct sx9500_data *data = iio_priv(indio_dev);
435
436 switch (chan->type) {
437 case IIO_PROXIMITY:
438 switch (mask) {
439 case IIO_CHAN_INFO_SAMP_FREQ:
440 return sx9500_set_samp_freq(data, val, val2);
441 default:
442 return -EINVAL;
443 }
444 default:
445 return -EINVAL;
446 }
447}
448
449static irqreturn_t sx9500_irq_handler(int irq, void *private)
450{
451 struct iio_dev *indio_dev = private;
452 struct sx9500_data *data = iio_priv(indio_dev);
453
454 if (data->trigger_enabled)
455 iio_trigger_poll(trig: data->trig);
456
457 /*
458 * Even if no event is enabled, we need to wake the thread to
459 * clear the interrupt state by reading SX9500_REG_IRQ_SRC. It
460 * is not possible to do that here because regmap_read takes a
461 * mutex.
462 */
463 return IRQ_WAKE_THREAD;
464}
465
466static void sx9500_push_events(struct iio_dev *indio_dev)
467{
468 int ret;
469 unsigned int val, chan;
470 struct sx9500_data *data = iio_priv(indio_dev);
471
472 ret = regmap_read(map: data->regmap, SX9500_REG_STAT, val: &val);
473 if (ret < 0) {
474 dev_err(&data->client->dev, "i2c transfer error in irq\n");
475 return;
476 }
477
478 val >>= SX9500_PROXSTAT_SHIFT;
479 for (chan = 0; chan < SX9500_NUM_CHANNELS; chan++) {
480 int dir;
481 u64 ev;
482 bool new_prox = val & BIT(chan);
483
484 if (!data->event_enabled[chan])
485 continue;
486 if (new_prox == data->prox_stat[chan])
487 /* No change on this channel. */
488 continue;
489
490 dir = new_prox ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
491 ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan,
492 IIO_EV_TYPE_THRESH, dir);
493 iio_push_event(indio_dev, ev_code: ev, timestamp: iio_get_time_ns(indio_dev));
494 data->prox_stat[chan] = new_prox;
495 }
496}
497
498static irqreturn_t sx9500_irq_thread_handler(int irq, void *private)
499{
500 struct iio_dev *indio_dev = private;
501 struct sx9500_data *data = iio_priv(indio_dev);
502 int ret;
503 unsigned int val;
504
505 mutex_lock(&data->mutex);
506
507 ret = regmap_read(map: data->regmap, SX9500_REG_IRQ_SRC, val: &val);
508 if (ret < 0) {
509 dev_err(&data->client->dev, "i2c transfer error in irq\n");
510 goto out;
511 }
512
513 if (val & (SX9500_CLOSE_IRQ | SX9500_FAR_IRQ))
514 sx9500_push_events(indio_dev);
515
516 if (val & SX9500_CONVDONE_IRQ)
517 complete(&data->completion);
518
519out:
520 mutex_unlock(lock: &data->mutex);
521
522 return IRQ_HANDLED;
523}
524
525static int sx9500_read_event_config(struct iio_dev *indio_dev,
526 const struct iio_chan_spec *chan,
527 enum iio_event_type type,
528 enum iio_event_direction dir)
529{
530 struct sx9500_data *data = iio_priv(indio_dev);
531
532 if (chan->type != IIO_PROXIMITY || type != IIO_EV_TYPE_THRESH ||
533 dir != IIO_EV_DIR_EITHER)
534 return -EINVAL;
535
536 return data->event_enabled[chan->channel];
537}
538
539static int sx9500_write_event_config(struct iio_dev *indio_dev,
540 const struct iio_chan_spec *chan,
541 enum iio_event_type type,
542 enum iio_event_direction dir,
543 int state)
544{
545 struct sx9500_data *data = iio_priv(indio_dev);
546 int ret;
547
548 if (chan->type != IIO_PROXIMITY || type != IIO_EV_TYPE_THRESH ||
549 dir != IIO_EV_DIR_EITHER)
550 return -EINVAL;
551
552 mutex_lock(&data->mutex);
553
554 if (state == 1) {
555 ret = sx9500_inc_chan_users(data, chan: chan->channel);
556 if (ret < 0)
557 goto out_unlock;
558 ret = sx9500_inc_close_far_users(data);
559 if (ret < 0)
560 goto out_undo_chan;
561 } else {
562 ret = sx9500_dec_chan_users(data, chan: chan->channel);
563 if (ret < 0)
564 goto out_unlock;
565 ret = sx9500_dec_close_far_users(data);
566 if (ret < 0)
567 goto out_undo_chan;
568 }
569
570 data->event_enabled[chan->channel] = state;
571 goto out_unlock;
572
573out_undo_chan:
574 if (state == 1)
575 sx9500_dec_chan_users(data, chan: chan->channel);
576 else
577 sx9500_inc_chan_users(data, chan: chan->channel);
578out_unlock:
579 mutex_unlock(lock: &data->mutex);
580 return ret;
581}
582
583static int sx9500_update_scan_mode(struct iio_dev *indio_dev,
584 const unsigned long *scan_mask)
585{
586 struct sx9500_data *data = iio_priv(indio_dev);
587
588 mutex_lock(&data->mutex);
589 kfree(objp: data->buffer);
590 data->buffer = kzalloc(size: indio_dev->scan_bytes, GFP_KERNEL);
591 mutex_unlock(lock: &data->mutex);
592
593 if (data->buffer == NULL)
594 return -ENOMEM;
595
596 return 0;
597}
598
599static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
600 "2.500000 3.333333 5 6.666666 8.333333 11.111111 16.666666 33.333333");
601
602static struct attribute *sx9500_attributes[] = {
603 &iio_const_attr_sampling_frequency_available.dev_attr.attr,
604 NULL,
605};
606
607static const struct attribute_group sx9500_attribute_group = {
608 .attrs = sx9500_attributes,
609};
610
611static const struct iio_info sx9500_info = {
612 .attrs = &sx9500_attribute_group,
613 .read_raw = &sx9500_read_raw,
614 .write_raw = &sx9500_write_raw,
615 .read_event_config = &sx9500_read_event_config,
616 .write_event_config = &sx9500_write_event_config,
617 .update_scan_mode = &sx9500_update_scan_mode,
618};
619
620static int sx9500_set_trigger_state(struct iio_trigger *trig,
621 bool state)
622{
623 struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
624 struct sx9500_data *data = iio_priv(indio_dev);
625 int ret;
626
627 mutex_lock(&data->mutex);
628
629 if (state)
630 ret = sx9500_inc_data_rdy_users(data);
631 else
632 ret = sx9500_dec_data_rdy_users(data);
633 if (ret < 0)
634 goto out;
635
636 data->trigger_enabled = state;
637
638out:
639 mutex_unlock(lock: &data->mutex);
640
641 return ret;
642}
643
644static const struct iio_trigger_ops sx9500_trigger_ops = {
645 .set_trigger_state = sx9500_set_trigger_state,
646};
647
648static irqreturn_t sx9500_trigger_handler(int irq, void *private)
649{
650 struct iio_poll_func *pf = private;
651 struct iio_dev *indio_dev = pf->indio_dev;
652 struct sx9500_data *data = iio_priv(indio_dev);
653 int val, bit, ret, i = 0;
654
655 mutex_lock(&data->mutex);
656
657 for_each_set_bit(bit, indio_dev->active_scan_mask,
658 indio_dev->masklength) {
659 ret = sx9500_read_prox_data(data, chan: &indio_dev->channels[bit],
660 val: &val);
661 if (ret < 0)
662 goto out;
663
664 data->buffer[i++] = val;
665 }
666
667 iio_push_to_buffers_with_timestamp(indio_dev, data: data->buffer,
668 timestamp: iio_get_time_ns(indio_dev));
669
670out:
671 mutex_unlock(lock: &data->mutex);
672
673 iio_trigger_notify_done(trig: indio_dev->trig);
674
675 return IRQ_HANDLED;
676}
677
678static int sx9500_buffer_postenable(struct iio_dev *indio_dev)
679{
680 struct sx9500_data *data = iio_priv(indio_dev);
681 int ret = 0, i;
682
683 mutex_lock(&data->mutex);
684
685 for (i = 0; i < SX9500_NUM_CHANNELS; i++)
686 if (test_bit(i, indio_dev->active_scan_mask)) {
687 ret = sx9500_inc_chan_users(data, chan: i);
688 if (ret)
689 break;
690 }
691
692 if (ret)
693 for (i = i - 1; i >= 0; i--)
694 if (test_bit(i, indio_dev->active_scan_mask))
695 sx9500_dec_chan_users(data, chan: i);
696
697 mutex_unlock(lock: &data->mutex);
698
699 return ret;
700}
701
702static int sx9500_buffer_predisable(struct iio_dev *indio_dev)
703{
704 struct sx9500_data *data = iio_priv(indio_dev);
705 int ret = 0, i;
706
707 mutex_lock(&data->mutex);
708
709 for (i = 0; i < SX9500_NUM_CHANNELS; i++)
710 if (test_bit(i, indio_dev->active_scan_mask)) {
711 ret = sx9500_dec_chan_users(data, chan: i);
712 if (ret)
713 break;
714 }
715
716 if (ret)
717 for (i = i - 1; i >= 0; i--)
718 if (test_bit(i, indio_dev->active_scan_mask))
719 sx9500_inc_chan_users(data, chan: i);
720
721 mutex_unlock(lock: &data->mutex);
722
723 return ret;
724}
725
726static const struct iio_buffer_setup_ops sx9500_buffer_setup_ops = {
727 .postenable = sx9500_buffer_postenable,
728 .predisable = sx9500_buffer_predisable,
729};
730
731struct sx9500_reg_default {
732 u8 reg;
733 u8 def;
734};
735
736static const struct sx9500_reg_default sx9500_default_regs[] = {
737 {
738 .reg = SX9500_REG_PROX_CTRL1,
739 /* Shield enabled, small range. */
740 .def = 0x43,
741 },
742 {
743 .reg = SX9500_REG_PROX_CTRL2,
744 /* x8 gain, 167kHz frequency, finest resolution. */
745 .def = 0x77,
746 },
747 {
748 .reg = SX9500_REG_PROX_CTRL3,
749 /* Doze enabled, 2x scan period doze, no raw filter. */
750 .def = 0x40,
751 },
752 {
753 .reg = SX9500_REG_PROX_CTRL4,
754 /* Average threshold. */
755 .def = 0x30,
756 },
757 {
758 .reg = SX9500_REG_PROX_CTRL5,
759 /*
760 * Debouncer off, lowest average negative filter,
761 * highest average positive filter.
762 */
763 .def = 0x0f,
764 },
765 {
766 .reg = SX9500_REG_PROX_CTRL6,
767 /* Proximity detection threshold: 280 */
768 .def = 0x0e,
769 },
770 {
771 .reg = SX9500_REG_PROX_CTRL7,
772 /*
773 * No automatic compensation, compensate each pin
774 * independently, proximity hysteresis: 32, close
775 * debouncer off, far debouncer off.
776 */
777 .def = 0x00,
778 },
779 {
780 .reg = SX9500_REG_PROX_CTRL8,
781 /* No stuck timeout, no periodic compensation. */
782 .def = 0x00,
783 },
784 {
785 .reg = SX9500_REG_PROX_CTRL0,
786 /* Scan period: 30ms, all sensors disabled. */
787 .def = 0x00,
788 },
789};
790
791/* Activate all channels and perform an initial compensation. */
792static int sx9500_init_compensation(struct iio_dev *indio_dev)
793{
794 struct sx9500_data *data = iio_priv(indio_dev);
795 int i, ret;
796 unsigned int val;
797
798 ret = regmap_update_bits(map: data->regmap, SX9500_REG_PROX_CTRL0,
799 SX9500_CHAN_MASK, SX9500_CHAN_MASK);
800 if (ret < 0)
801 return ret;
802
803 for (i = 10; i >= 0; i--) {
804 usleep_range(min: 10000, max: 20000);
805 ret = regmap_read(map: data->regmap, SX9500_REG_STAT, val: &val);
806 if (ret < 0)
807 goto out;
808 if (!(val & SX9500_COMPSTAT_MASK))
809 break;
810 }
811
812 if (i < 0) {
813 dev_err(&data->client->dev, "initial compensation timed out");
814 ret = -ETIMEDOUT;
815 }
816
817out:
818 regmap_update_bits(map: data->regmap, SX9500_REG_PROX_CTRL0,
819 SX9500_CHAN_MASK, val: 0);
820 return ret;
821}
822
823static int sx9500_init_device(struct iio_dev *indio_dev)
824{
825 struct sx9500_data *data = iio_priv(indio_dev);
826 int ret, i;
827 unsigned int val;
828
829 if (data->gpiod_rst) {
830 gpiod_set_value_cansleep(desc: data->gpiod_rst, value: 0);
831 usleep_range(min: 1000, max: 2000);
832 gpiod_set_value_cansleep(desc: data->gpiod_rst, value: 1);
833 usleep_range(min: 1000, max: 2000);
834 }
835
836 ret = regmap_write(map: data->regmap, SX9500_REG_IRQ_MSK, val: 0);
837 if (ret < 0)
838 return ret;
839
840 ret = regmap_write(map: data->regmap, SX9500_REG_RESET,
841 SX9500_SOFT_RESET);
842 if (ret < 0)
843 return ret;
844
845 ret = regmap_read(map: data->regmap, SX9500_REG_IRQ_SRC, val: &val);
846 if (ret < 0)
847 return ret;
848
849 for (i = 0; i < ARRAY_SIZE(sx9500_default_regs); i++) {
850 ret = regmap_write(map: data->regmap,
851 reg: sx9500_default_regs[i].reg,
852 val: sx9500_default_regs[i].def);
853 if (ret < 0)
854 return ret;
855 }
856
857 return sx9500_init_compensation(indio_dev);
858}
859
860static const struct acpi_gpio_params reset_gpios = { 0, 0, false };
861static const struct acpi_gpio_params interrupt_gpios = { 2, 0, false };
862
863static const struct acpi_gpio_mapping acpi_sx9500_gpios[] = {
864 { "reset-gpios", &reset_gpios, 1 },
865 /*
866 * Some platforms have a bug in ACPI GPIO description making IRQ
867 * GPIO to be output only. Ask the GPIO core to ignore this limit.
868 */
869 { "interrupt-gpios", &interrupt_gpios, 1, ACPI_GPIO_QUIRK_NO_IO_RESTRICTION },
870 { },
871};
872
873static void sx9500_gpio_probe(struct i2c_client *client,
874 struct sx9500_data *data)
875{
876 struct gpio_desc *gpiod_int;
877 struct device *dev;
878 int ret;
879
880 if (!client)
881 return;
882
883 dev = &client->dev;
884
885 ret = devm_acpi_dev_add_driver_gpios(dev, gpios: acpi_sx9500_gpios);
886 if (ret)
887 dev_dbg(dev, "Unable to add GPIO mapping table\n");
888
889 if (client->irq <= 0) {
890 gpiod_int = devm_gpiod_get(dev, con_id: "interrupt", flags: GPIOD_IN);
891 if (IS_ERR(ptr: gpiod_int))
892 dev_err(dev, "gpio get irq failed\n");
893 else
894 client->irq = gpiod_to_irq(desc: gpiod_int);
895 }
896
897 data->gpiod_rst = devm_gpiod_get(dev, con_id: "reset", flags: GPIOD_OUT_HIGH);
898 if (IS_ERR(ptr: data->gpiod_rst)) {
899 dev_warn(dev, "gpio get reset pin failed\n");
900 data->gpiod_rst = NULL;
901 }
902}
903
904static int sx9500_probe(struct i2c_client *client)
905{
906 int ret;
907 struct iio_dev *indio_dev;
908 struct sx9500_data *data;
909
910 indio_dev = devm_iio_device_alloc(parent: &client->dev, sizeof_priv: sizeof(*data));
911 if (indio_dev == NULL)
912 return -ENOMEM;
913
914 data = iio_priv(indio_dev);
915 data->client = client;
916 mutex_init(&data->mutex);
917 init_completion(x: &data->completion);
918 data->trigger_enabled = false;
919
920 data->regmap = devm_regmap_init_i2c(client, &sx9500_regmap_config);
921 if (IS_ERR(ptr: data->regmap))
922 return PTR_ERR(ptr: data->regmap);
923
924 indio_dev->name = SX9500_DRIVER_NAME;
925 indio_dev->channels = sx9500_channels;
926 indio_dev->num_channels = ARRAY_SIZE(sx9500_channels);
927 indio_dev->info = &sx9500_info;
928 indio_dev->modes = INDIO_DIRECT_MODE;
929 i2c_set_clientdata(client, data: indio_dev);
930
931 sx9500_gpio_probe(client, data);
932
933 ret = sx9500_init_device(indio_dev);
934 if (ret < 0)
935 return ret;
936
937 if (client->irq <= 0)
938 dev_warn(&client->dev, "no valid irq found\n");
939 else {
940 ret = devm_request_threaded_irq(dev: &client->dev, irq: client->irq,
941 handler: sx9500_irq_handler, thread_fn: sx9500_irq_thread_handler,
942 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
943 SX9500_IRQ_NAME, dev_id: indio_dev);
944 if (ret < 0)
945 return ret;
946
947 data->trig = devm_iio_trigger_alloc(&client->dev,
948 "%s-dev%d", indio_dev->name, iio_device_id(indio_dev));
949 if (!data->trig)
950 return -ENOMEM;
951
952 data->trig->ops = &sx9500_trigger_ops;
953 iio_trigger_set_drvdata(trig: data->trig, data: indio_dev);
954
955 ret = iio_trigger_register(trig_info: data->trig);
956 if (ret)
957 return ret;
958 }
959
960 ret = iio_triggered_buffer_setup(indio_dev, NULL,
961 sx9500_trigger_handler,
962 &sx9500_buffer_setup_ops);
963 if (ret < 0)
964 goto out_trigger_unregister;
965
966 ret = iio_device_register(indio_dev);
967 if (ret < 0)
968 goto out_buffer_cleanup;
969
970 return 0;
971
972out_buffer_cleanup:
973 iio_triggered_buffer_cleanup(indio_dev);
974out_trigger_unregister:
975 if (client->irq > 0)
976 iio_trigger_unregister(trig_info: data->trig);
977
978 return ret;
979}
980
981static void sx9500_remove(struct i2c_client *client)
982{
983 struct iio_dev *indio_dev = i2c_get_clientdata(client);
984 struct sx9500_data *data = iio_priv(indio_dev);
985
986 iio_device_unregister(indio_dev);
987 iio_triggered_buffer_cleanup(indio_dev);
988 if (client->irq > 0)
989 iio_trigger_unregister(trig_info: data->trig);
990 kfree(objp: data->buffer);
991}
992
993static int sx9500_suspend(struct device *dev)
994{
995 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
996 struct sx9500_data *data = iio_priv(indio_dev);
997 int ret;
998
999 mutex_lock(&data->mutex);
1000 ret = regmap_read(map: data->regmap, SX9500_REG_PROX_CTRL0,
1001 val: &data->suspend_ctrl0);
1002 if (ret < 0)
1003 goto out;
1004
1005 /*
1006 * Scan period doesn't matter because when all the sensors are
1007 * deactivated the device is in sleep mode.
1008 */
1009 ret = regmap_write(map: data->regmap, SX9500_REG_PROX_CTRL0, val: 0);
1010
1011out:
1012 mutex_unlock(lock: &data->mutex);
1013 return ret;
1014}
1015
1016static int sx9500_resume(struct device *dev)
1017{
1018 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1019 struct sx9500_data *data = iio_priv(indio_dev);
1020 int ret;
1021
1022 mutex_lock(&data->mutex);
1023 ret = regmap_write(map: data->regmap, SX9500_REG_PROX_CTRL0,
1024 val: data->suspend_ctrl0);
1025 mutex_unlock(lock: &data->mutex);
1026
1027 return ret;
1028}
1029
1030static DEFINE_SIMPLE_DEV_PM_OPS(sx9500_pm_ops, sx9500_suspend, sx9500_resume);
1031
1032static const struct acpi_device_id sx9500_acpi_match[] = {
1033 {"SSX9500", 0},
1034 {"SASX9500", 0},
1035 { },
1036};
1037MODULE_DEVICE_TABLE(acpi, sx9500_acpi_match);
1038
1039static const struct of_device_id sx9500_of_match[] = {
1040 { .compatible = "semtech,sx9500", },
1041 { }
1042};
1043MODULE_DEVICE_TABLE(of, sx9500_of_match);
1044
1045static const struct i2c_device_id sx9500_id[] = {
1046 {"sx9500", 0},
1047 { },
1048};
1049MODULE_DEVICE_TABLE(i2c, sx9500_id);
1050
1051static struct i2c_driver sx9500_driver = {
1052 .driver = {
1053 .name = SX9500_DRIVER_NAME,
1054 .acpi_match_table = sx9500_acpi_match,
1055 .of_match_table = sx9500_of_match,
1056 .pm = pm_sleep_ptr(&sx9500_pm_ops),
1057 },
1058 .probe = sx9500_probe,
1059 .remove = sx9500_remove,
1060 .id_table = sx9500_id,
1061};
1062module_i2c_driver(sx9500_driver);
1063
1064MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
1065MODULE_DESCRIPTION("Driver for Semtech SX9500 proximity sensor");
1066MODULE_LICENSE("GPL v2");
1067

source code of linux/drivers/iio/proximity/sx9500.c