xref: /linux/drivers/iio/proximity/sx9500.c (revision 005438a8eef063495ac059d128eea71b58de50e5)
1 /*
2  * Copyright (c) 2014 Intel Corporation
3  *
4  * Driver for Semtech's SX9500 capacitive proximity/button solution.
5  * Datasheet available at
6  * <http://www.semtech.com/images/datasheet/sx9500.pdf>.
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms of the GNU General Public License version 2 as published by
10  * the Free Software Foundation.
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/module.h>
16 #include <linux/i2c.h>
17 #include <linux/irq.h>
18 #include <linux/acpi.h>
19 #include <linux/gpio/consumer.h>
20 #include <linux/regmap.h>
21 #include <linux/pm.h>
22 #include <linux/delay.h>
23 
24 #include <linux/iio/iio.h>
25 #include <linux/iio/buffer.h>
26 #include <linux/iio/sysfs.h>
27 #include <linux/iio/events.h>
28 #include <linux/iio/trigger.h>
29 #include <linux/iio/triggered_buffer.h>
30 #include <linux/iio/trigger_consumer.h>
31 
32 #define SX9500_DRIVER_NAME		"sx9500"
33 #define SX9500_IRQ_NAME			"sx9500_event"
34 
35 #define SX9500_GPIO_INT			"interrupt"
36 #define SX9500_GPIO_RESET		"reset"
37 
38 /* Register definitions. */
39 #define SX9500_REG_IRQ_SRC		0x00
40 #define SX9500_REG_STAT			0x01
41 #define SX9500_REG_IRQ_MSK		0x03
42 
43 #define SX9500_REG_PROX_CTRL0		0x06
44 #define SX9500_REG_PROX_CTRL1		0x07
45 #define SX9500_REG_PROX_CTRL2		0x08
46 #define SX9500_REG_PROX_CTRL3		0x09
47 #define SX9500_REG_PROX_CTRL4		0x0a
48 #define SX9500_REG_PROX_CTRL5		0x0b
49 #define SX9500_REG_PROX_CTRL6		0x0c
50 #define SX9500_REG_PROX_CTRL7		0x0d
51 #define SX9500_REG_PROX_CTRL8		0x0e
52 
53 #define SX9500_REG_SENSOR_SEL		0x20
54 #define SX9500_REG_USE_MSB		0x21
55 #define SX9500_REG_USE_LSB		0x22
56 #define SX9500_REG_AVG_MSB		0x23
57 #define SX9500_REG_AVG_LSB		0x24
58 #define SX9500_REG_DIFF_MSB		0x25
59 #define SX9500_REG_DIFF_LSB		0x26
60 #define SX9500_REG_OFFSET_MSB		0x27
61 #define SX9500_REG_OFFSET_LSB		0x28
62 
63 #define SX9500_REG_RESET		0x7f
64 
65 /* Write this to REG_RESET to do a soft reset. */
66 #define SX9500_SOFT_RESET		0xde
67 
68 #define SX9500_SCAN_PERIOD_MASK		GENMASK(6, 4)
69 #define SX9500_SCAN_PERIOD_SHIFT	4
70 
71 /*
72  * These serve for identifying IRQ source in the IRQ_SRC register, and
73  * also for masking the IRQs in the IRQ_MSK register.
74  */
75 #define SX9500_CLOSE_IRQ		BIT(6)
76 #define SX9500_FAR_IRQ			BIT(5)
77 #define SX9500_CONVDONE_IRQ		BIT(3)
78 
79 #define SX9500_PROXSTAT_SHIFT		4
80 #define SX9500_COMPSTAT_MASK		GENMASK(3, 0)
81 
82 #define SX9500_NUM_CHANNELS		4
83 
84 struct sx9500_data {
85 	struct mutex mutex;
86 	struct i2c_client *client;
87 	struct iio_trigger *trig;
88 	struct regmap *regmap;
89 	struct gpio_desc *gpiod_rst;
90 	/*
91 	 * Last reading of the proximity status for each channel.  We
92 	 * only send an event to user space when this changes.
93 	 */
94 	bool prox_stat[SX9500_NUM_CHANNELS];
95 	bool event_enabled[SX9500_NUM_CHANNELS];
96 	bool trigger_enabled;
97 	u16 *buffer;
98 	/* Remember enabled channels and sample rate during suspend. */
99 	unsigned int suspend_ctrl0;
100 	struct completion completion;
101 	int data_rdy_users, close_far_users;
102 	int channel_users[SX9500_NUM_CHANNELS];
103 };
104 
105 static const struct iio_event_spec sx9500_events[] = {
106 	{
107 		.type = IIO_EV_TYPE_THRESH,
108 		.dir = IIO_EV_DIR_EITHER,
109 		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
110 	},
111 };
112 
113 #define SX9500_CHANNEL(idx)					\
114 	{							\
115 		.type = IIO_PROXIMITY,				\
116 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
117 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
118 		.indexed = 1,					\
119 		.channel = idx,					\
120 		.event_spec = sx9500_events,			\
121 		.num_event_specs = ARRAY_SIZE(sx9500_events),	\
122 		.scan_index = idx,				\
123 		.scan_type = {					\
124 			.sign = 'u',				\
125 			.realbits = 16,				\
126 			.storagebits = 16,			\
127 			.shift = 0,				\
128 		},						\
129 	}
130 
131 static const struct iio_chan_spec sx9500_channels[] = {
132 	SX9500_CHANNEL(0),
133 	SX9500_CHANNEL(1),
134 	SX9500_CHANNEL(2),
135 	SX9500_CHANNEL(3),
136 	IIO_CHAN_SOFT_TIMESTAMP(4),
137 };
138 
139 static const struct {
140 	int val;
141 	int val2;
142 } sx9500_samp_freq_table[] = {
143 	{33, 333333},
144 	{16, 666666},
145 	{11, 111111},
146 	{8, 333333},
147 	{6, 666666},
148 	{5, 0},
149 	{3, 333333},
150 	{2, 500000},
151 };
152 
153 static const unsigned int sx9500_scan_period_table[] = {
154 	30, 60, 90, 120, 150, 200, 300, 400,
155 };
156 
157 static const struct regmap_range sx9500_writable_reg_ranges[] = {
158 	regmap_reg_range(SX9500_REG_IRQ_MSK, SX9500_REG_IRQ_MSK),
159 	regmap_reg_range(SX9500_REG_PROX_CTRL0, SX9500_REG_PROX_CTRL8),
160 	regmap_reg_range(SX9500_REG_SENSOR_SEL, SX9500_REG_SENSOR_SEL),
161 	regmap_reg_range(SX9500_REG_OFFSET_MSB, SX9500_REG_OFFSET_LSB),
162 	regmap_reg_range(SX9500_REG_RESET, SX9500_REG_RESET),
163 };
164 
165 static const struct regmap_access_table sx9500_writeable_regs = {
166 	.yes_ranges = sx9500_writable_reg_ranges,
167 	.n_yes_ranges = ARRAY_SIZE(sx9500_writable_reg_ranges),
168 };
169 
170 /*
171  * All allocated registers are readable, so we just list unallocated
172  * ones.
173  */
174 static const struct regmap_range sx9500_non_readable_reg_ranges[] = {
175 	regmap_reg_range(SX9500_REG_STAT + 1, SX9500_REG_STAT + 1),
176 	regmap_reg_range(SX9500_REG_IRQ_MSK + 1, SX9500_REG_PROX_CTRL0 - 1),
177 	regmap_reg_range(SX9500_REG_PROX_CTRL8 + 1, SX9500_REG_SENSOR_SEL - 1),
178 	regmap_reg_range(SX9500_REG_OFFSET_LSB + 1, SX9500_REG_RESET - 1),
179 };
180 
181 static const struct regmap_access_table sx9500_readable_regs = {
182 	.no_ranges = sx9500_non_readable_reg_ranges,
183 	.n_no_ranges = ARRAY_SIZE(sx9500_non_readable_reg_ranges),
184 };
185 
186 static const struct regmap_range sx9500_volatile_reg_ranges[] = {
187 	regmap_reg_range(SX9500_REG_IRQ_SRC, SX9500_REG_STAT),
188 	regmap_reg_range(SX9500_REG_USE_MSB, SX9500_REG_OFFSET_LSB),
189 	regmap_reg_range(SX9500_REG_RESET, SX9500_REG_RESET),
190 };
191 
192 static const struct regmap_access_table sx9500_volatile_regs = {
193 	.yes_ranges = sx9500_volatile_reg_ranges,
194 	.n_yes_ranges = ARRAY_SIZE(sx9500_volatile_reg_ranges),
195 };
196 
197 static const struct regmap_config sx9500_regmap_config = {
198 	.reg_bits = 8,
199 	.val_bits = 8,
200 
201 	.max_register = SX9500_REG_RESET,
202 	.cache_type = REGCACHE_RBTREE,
203 
204 	.wr_table = &sx9500_writeable_regs,
205 	.rd_table = &sx9500_readable_regs,
206 	.volatile_table = &sx9500_volatile_regs,
207 };
208 
209 static int sx9500_inc_users(struct sx9500_data *data, int *counter,
210 			    unsigned int reg, unsigned int bitmask)
211 {
212 	(*counter)++;
213 	if (*counter != 1)
214 		/* Bit is already active, nothing to do. */
215 		return 0;
216 
217 	return regmap_update_bits(data->regmap, reg, bitmask, bitmask);
218 }
219 
220 static int sx9500_dec_users(struct sx9500_data *data, int *counter,
221 			    unsigned int reg, unsigned int bitmask)
222 {
223 	(*counter)--;
224 	if (*counter != 0)
225 		/* There are more users, do not deactivate. */
226 		return 0;
227 
228 	return regmap_update_bits(data->regmap, reg, bitmask, 0);
229 }
230 
231 static int sx9500_inc_chan_users(struct sx9500_data *data, int chan)
232 {
233 	return sx9500_inc_users(data, &data->channel_users[chan],
234 				SX9500_REG_PROX_CTRL0, BIT(chan));
235 }
236 
237 static int sx9500_dec_chan_users(struct sx9500_data *data, int chan)
238 {
239 	return sx9500_dec_users(data, &data->channel_users[chan],
240 				SX9500_REG_PROX_CTRL0, BIT(chan));
241 }
242 
243 static int sx9500_inc_data_rdy_users(struct sx9500_data *data)
244 {
245 	return sx9500_inc_users(data, &data->data_rdy_users,
246 				SX9500_REG_IRQ_MSK, SX9500_CONVDONE_IRQ);
247 }
248 
249 static int sx9500_dec_data_rdy_users(struct sx9500_data *data)
250 {
251 	return sx9500_dec_users(data, &data->data_rdy_users,
252 				SX9500_REG_IRQ_MSK, SX9500_CONVDONE_IRQ);
253 }
254 
255 static int sx9500_inc_close_far_users(struct sx9500_data *data)
256 {
257 	return sx9500_inc_users(data, &data->close_far_users,
258 				SX9500_REG_IRQ_MSK,
259 				SX9500_CLOSE_IRQ | SX9500_FAR_IRQ);
260 }
261 
262 static int sx9500_dec_close_far_users(struct sx9500_data *data)
263 {
264 	return sx9500_dec_users(data, &data->close_far_users,
265 				SX9500_REG_IRQ_MSK,
266 				SX9500_CLOSE_IRQ | SX9500_FAR_IRQ);
267 }
268 
269 static int sx9500_read_prox_data(struct sx9500_data *data,
270 				 const struct iio_chan_spec *chan,
271 				 int *val)
272 {
273 	int ret;
274 	__be16 regval;
275 
276 	ret = regmap_write(data->regmap, SX9500_REG_SENSOR_SEL, chan->channel);
277 	if (ret < 0)
278 		return ret;
279 
280 	ret = regmap_bulk_read(data->regmap, SX9500_REG_USE_MSB, &regval, 2);
281 	if (ret < 0)
282 		return ret;
283 
284 	*val = 32767 - (s16)be16_to_cpu(regval);
285 
286 	return IIO_VAL_INT;
287 }
288 
289 /*
290  * If we have no interrupt support, we have to wait for a scan period
291  * after enabling a channel to get a result.
292  */
293 static int sx9500_wait_for_sample(struct sx9500_data *data)
294 {
295 	int ret;
296 	unsigned int val;
297 
298 	ret = regmap_read(data->regmap, SX9500_REG_PROX_CTRL0, &val);
299 	if (ret < 0)
300 		return ret;
301 
302 	val = (val & SX9500_SCAN_PERIOD_MASK) >> SX9500_SCAN_PERIOD_SHIFT;
303 
304 	msleep(sx9500_scan_period_table[val]);
305 
306 	return 0;
307 }
308 
309 static int sx9500_read_proximity(struct sx9500_data *data,
310 				 const struct iio_chan_spec *chan,
311 				 int *val)
312 {
313 	int ret;
314 
315 	mutex_lock(&data->mutex);
316 
317 	ret = sx9500_inc_chan_users(data, chan->channel);
318 	if (ret < 0)
319 		goto out;
320 
321 	ret = sx9500_inc_data_rdy_users(data);
322 	if (ret < 0)
323 		goto out_dec_chan;
324 
325 	mutex_unlock(&data->mutex);
326 
327 	if (data->client->irq > 0)
328 		ret = wait_for_completion_interruptible(&data->completion);
329 	else
330 		ret = sx9500_wait_for_sample(data);
331 
332 	if (ret < 0)
333 		return ret;
334 
335 	mutex_lock(&data->mutex);
336 
337 	ret = sx9500_read_prox_data(data, chan, val);
338 	if (ret < 0)
339 		goto out;
340 
341 	ret = sx9500_dec_chan_users(data, chan->channel);
342 	if (ret < 0)
343 		goto out;
344 
345 	ret = sx9500_dec_data_rdy_users(data);
346 	if (ret < 0)
347 		goto out;
348 
349 	ret = IIO_VAL_INT;
350 
351 	goto out;
352 
353 out_dec_chan:
354 	sx9500_dec_chan_users(data, chan->channel);
355 out:
356 	mutex_unlock(&data->mutex);
357 	reinit_completion(&data->completion);
358 
359 	return ret;
360 }
361 
362 static int sx9500_read_samp_freq(struct sx9500_data *data,
363 				 int *val, int *val2)
364 {
365 	int ret;
366 	unsigned int regval;
367 
368 	mutex_lock(&data->mutex);
369 	ret = regmap_read(data->regmap, SX9500_REG_PROX_CTRL0, &regval);
370 	mutex_unlock(&data->mutex);
371 
372 	if (ret < 0)
373 		return ret;
374 
375 	regval = (regval & SX9500_SCAN_PERIOD_MASK) >> SX9500_SCAN_PERIOD_SHIFT;
376 	*val = sx9500_samp_freq_table[regval].val;
377 	*val2 = sx9500_samp_freq_table[regval].val2;
378 
379 	return IIO_VAL_INT_PLUS_MICRO;
380 }
381 
382 static int sx9500_read_raw(struct iio_dev *indio_dev,
383 			   const struct iio_chan_spec *chan,
384 			   int *val, int *val2, long mask)
385 {
386 	struct sx9500_data *data = iio_priv(indio_dev);
387 
388 	switch (chan->type) {
389 	case IIO_PROXIMITY:
390 		switch (mask) {
391 		case IIO_CHAN_INFO_RAW:
392 			if (iio_buffer_enabled(indio_dev))
393 				return -EBUSY;
394 			return sx9500_read_proximity(data, chan, val);
395 		case IIO_CHAN_INFO_SAMP_FREQ:
396 			return sx9500_read_samp_freq(data, val, val2);
397 		default:
398 			return -EINVAL;
399 		}
400 	default:
401 		return -EINVAL;
402 	}
403 }
404 
405 static int sx9500_set_samp_freq(struct sx9500_data *data,
406 				int val, int val2)
407 {
408 	int i, ret;
409 
410 	for (i = 0; i < ARRAY_SIZE(sx9500_samp_freq_table); i++)
411 		if (val == sx9500_samp_freq_table[i].val &&
412 		    val2 == sx9500_samp_freq_table[i].val2)
413 			break;
414 
415 	if (i == ARRAY_SIZE(sx9500_samp_freq_table))
416 		return -EINVAL;
417 
418 	mutex_lock(&data->mutex);
419 
420 	ret = regmap_update_bits(data->regmap, SX9500_REG_PROX_CTRL0,
421 				 SX9500_SCAN_PERIOD_MASK,
422 				 i << SX9500_SCAN_PERIOD_SHIFT);
423 
424 	mutex_unlock(&data->mutex);
425 
426 	return ret;
427 }
428 
429 static int sx9500_write_raw(struct iio_dev *indio_dev,
430 			    const struct iio_chan_spec *chan,
431 			    int val, int val2, long mask)
432 {
433 	struct sx9500_data *data = iio_priv(indio_dev);
434 
435 	switch (chan->type) {
436 	case IIO_PROXIMITY:
437 		switch (mask) {
438 		case IIO_CHAN_INFO_SAMP_FREQ:
439 			return sx9500_set_samp_freq(data, val, val2);
440 		default:
441 			return -EINVAL;
442 		}
443 	default:
444 		return -EINVAL;
445 	}
446 }
447 
448 static irqreturn_t sx9500_irq_handler(int irq, void *private)
449 {
450 	struct iio_dev *indio_dev = private;
451 	struct sx9500_data *data = iio_priv(indio_dev);
452 
453 	if (data->trigger_enabled)
454 		iio_trigger_poll(data->trig);
455 
456 	/*
457 	 * Even if no event is enabled, we need to wake the thread to
458 	 * clear the interrupt state by reading SX9500_REG_IRQ_SRC.  It
459 	 * is not possible to do that here because regmap_read takes a
460 	 * mutex.
461 	 */
462 	return IRQ_WAKE_THREAD;
463 }
464 
465 static void sx9500_push_events(struct iio_dev *indio_dev)
466 {
467 	int ret;
468 	unsigned int val, chan;
469 	struct sx9500_data *data = iio_priv(indio_dev);
470 
471 	ret = regmap_read(data->regmap, SX9500_REG_STAT, &val);
472 	if (ret < 0) {
473 		dev_err(&data->client->dev, "i2c transfer error in irq\n");
474 		return;
475 	}
476 
477 	val >>= SX9500_PROXSTAT_SHIFT;
478 	for (chan = 0; chan < SX9500_NUM_CHANNELS; chan++) {
479 		int dir;
480 		u64 ev;
481 		bool new_prox = val & BIT(chan);
482 
483 		if (!data->event_enabled[chan])
484 			continue;
485 		if (new_prox == data->prox_stat[chan])
486 			/* No change on this channel. */
487 			continue;
488 
489 		dir = new_prox ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
490 		ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan,
491 					  IIO_EV_TYPE_THRESH, dir);
492 		iio_push_event(indio_dev, ev, iio_get_time_ns());
493 		data->prox_stat[chan] = new_prox;
494 	}
495 }
496 
497 static irqreturn_t sx9500_irq_thread_handler(int irq, void *private)
498 {
499 	struct iio_dev *indio_dev = private;
500 	struct sx9500_data *data = iio_priv(indio_dev);
501 	int ret;
502 	unsigned int val;
503 
504 	mutex_lock(&data->mutex);
505 
506 	ret = regmap_read(data->regmap, SX9500_REG_IRQ_SRC, &val);
507 	if (ret < 0) {
508 		dev_err(&data->client->dev, "i2c transfer error in irq\n");
509 		goto out;
510 	}
511 
512 	if (val & (SX9500_CLOSE_IRQ | SX9500_FAR_IRQ))
513 		sx9500_push_events(indio_dev);
514 
515 	if (val & SX9500_CONVDONE_IRQ)
516 		complete_all(&data->completion);
517 
518 out:
519 	mutex_unlock(&data->mutex);
520 
521 	return IRQ_HANDLED;
522 }
523 
524 static int sx9500_read_event_config(struct iio_dev *indio_dev,
525 				    const struct iio_chan_spec *chan,
526 				    enum iio_event_type type,
527 				    enum iio_event_direction dir)
528 {
529 	struct sx9500_data *data = iio_priv(indio_dev);
530 
531 	if (chan->type != IIO_PROXIMITY || type != IIO_EV_TYPE_THRESH ||
532 	    dir != IIO_EV_DIR_EITHER)
533 		return -EINVAL;
534 
535 	return data->event_enabled[chan->channel];
536 }
537 
538 static int sx9500_write_event_config(struct iio_dev *indio_dev,
539 				     const struct iio_chan_spec *chan,
540 				     enum iio_event_type type,
541 				     enum iio_event_direction dir,
542 				     int state)
543 {
544 	struct sx9500_data *data = iio_priv(indio_dev);
545 	int ret;
546 
547 	if (chan->type != IIO_PROXIMITY || type != IIO_EV_TYPE_THRESH ||
548 	    dir != IIO_EV_DIR_EITHER)
549 		return -EINVAL;
550 
551 	mutex_lock(&data->mutex);
552 
553 	if (state == 1) {
554 		ret = sx9500_inc_chan_users(data, chan->channel);
555 		if (ret < 0)
556 			goto out_unlock;
557 		ret = sx9500_inc_close_far_users(data);
558 		if (ret < 0)
559 			goto out_undo_chan;
560 	} else {
561 		ret = sx9500_dec_chan_users(data, chan->channel);
562 		if (ret < 0)
563 			goto out_unlock;
564 		ret = sx9500_dec_close_far_users(data);
565 		if (ret < 0)
566 			goto out_undo_chan;
567 	}
568 
569 	data->event_enabled[chan->channel] = state;
570 	goto out_unlock;
571 
572 out_undo_chan:
573 	if (state == 1)
574 		sx9500_dec_chan_users(data, chan->channel);
575 	else
576 		sx9500_inc_chan_users(data, chan->channel);
577 out_unlock:
578 	mutex_unlock(&data->mutex);
579 	return ret;
580 }
581 
582 static int sx9500_update_scan_mode(struct iio_dev *indio_dev,
583 				   const unsigned long *scan_mask)
584 {
585 	struct sx9500_data *data = iio_priv(indio_dev);
586 
587 	mutex_lock(&data->mutex);
588 	kfree(data->buffer);
589 	data->buffer = kzalloc(indio_dev->scan_bytes, GFP_KERNEL);
590 	mutex_unlock(&data->mutex);
591 
592 	if (data->buffer == NULL)
593 		return -ENOMEM;
594 
595 	return 0;
596 }
597 
598 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
599 	"2.500000 3.333333 5 6.666666 8.333333 11.111111 16.666666 33.333333");
600 
601 static struct attribute *sx9500_attributes[] = {
602 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
603 	NULL,
604 };
605 
606 static const struct attribute_group sx9500_attribute_group = {
607 	.attrs = sx9500_attributes,
608 };
609 
610 static const struct iio_info sx9500_info = {
611 	.driver_module = THIS_MODULE,
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 
620 static 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 
638 out:
639 	mutex_unlock(&data->mutex);
640 
641 	return ret;
642 }
643 
644 static const struct iio_trigger_ops sx9500_trigger_ops = {
645 	.set_trigger_state = sx9500_set_trigger_state,
646 	.owner = THIS_MODULE,
647 };
648 
649 static irqreturn_t sx9500_trigger_handler(int irq, void *private)
650 {
651 	struct iio_poll_func *pf = private;
652 	struct iio_dev *indio_dev = pf->indio_dev;
653 	struct sx9500_data *data = iio_priv(indio_dev);
654 	int val, bit, ret, i = 0;
655 
656 	mutex_lock(&data->mutex);
657 
658 	for_each_set_bit(bit, indio_dev->active_scan_mask,
659 			 indio_dev->masklength) {
660 		ret = sx9500_read_prox_data(data, &indio_dev->channels[bit],
661 					    &val);
662 		if (ret < 0)
663 			goto out;
664 
665 		data->buffer[i++] = val;
666 	}
667 
668 	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
669 					   iio_get_time_ns());
670 
671 out:
672 	mutex_unlock(&data->mutex);
673 
674 	iio_trigger_notify_done(indio_dev->trig);
675 
676 	return IRQ_HANDLED;
677 }
678 
679 static int sx9500_buffer_preenable(struct iio_dev *indio_dev)
680 {
681 	struct sx9500_data *data = iio_priv(indio_dev);
682 	int ret, i;
683 
684 	mutex_lock(&data->mutex);
685 
686 	for (i = 0; i < SX9500_NUM_CHANNELS; i++)
687 		if (test_bit(i, indio_dev->active_scan_mask)) {
688 			ret = sx9500_inc_chan_users(data, i);
689 			if (ret)
690 				break;
691 		}
692 
693 	if (ret)
694 		for (i = i - 1; i >= 0; i--)
695 			if (test_bit(i, indio_dev->active_scan_mask))
696 				sx9500_dec_chan_users(data, i);
697 
698 	mutex_unlock(&data->mutex);
699 
700 	return ret;
701 }
702 
703 static int sx9500_buffer_predisable(struct iio_dev *indio_dev)
704 {
705 	struct sx9500_data *data = iio_priv(indio_dev);
706 	int ret, i;
707 
708 	iio_triggered_buffer_predisable(indio_dev);
709 
710 	mutex_lock(&data->mutex);
711 
712 	for (i = 0; i < SX9500_NUM_CHANNELS; i++)
713 		if (test_bit(i, indio_dev->active_scan_mask)) {
714 			ret = sx9500_dec_chan_users(data, i);
715 			if (ret)
716 				break;
717 		}
718 
719 	if (ret)
720 		for (i = i - 1; i >= 0; i--)
721 			if (test_bit(i, indio_dev->active_scan_mask))
722 				sx9500_inc_chan_users(data, i);
723 
724 	mutex_unlock(&data->mutex);
725 
726 	return ret;
727 }
728 
729 static const struct iio_buffer_setup_ops sx9500_buffer_setup_ops = {
730 	.preenable = sx9500_buffer_preenable,
731 	.postenable = iio_triggered_buffer_postenable,
732 	.predisable = sx9500_buffer_predisable,
733 };
734 
735 struct sx9500_reg_default {
736 	u8 reg;
737 	u8 def;
738 };
739 
740 static const struct sx9500_reg_default sx9500_default_regs[] = {
741 	{
742 		.reg = SX9500_REG_PROX_CTRL1,
743 		/* Shield enabled, small range. */
744 		.def = 0x43,
745 	},
746 	{
747 		.reg = SX9500_REG_PROX_CTRL2,
748 		/* x8 gain, 167kHz frequency, finest resolution. */
749 		.def = 0x77,
750 	},
751 	{
752 		.reg = SX9500_REG_PROX_CTRL3,
753 		/* Doze enabled, 2x scan period doze, no raw filter. */
754 		.def = 0x40,
755 	},
756 	{
757 		.reg = SX9500_REG_PROX_CTRL4,
758 		/* Average threshold. */
759 		.def = 0x30,
760 	},
761 	{
762 		.reg = SX9500_REG_PROX_CTRL5,
763 		/*
764 		 * Debouncer off, lowest average negative filter,
765 		 * highest average postive filter.
766 		 */
767 		.def = 0x0f,
768 	},
769 	{
770 		.reg = SX9500_REG_PROX_CTRL6,
771 		/* Proximity detection threshold: 280 */
772 		.def = 0x0e,
773 	},
774 	{
775 		.reg = SX9500_REG_PROX_CTRL7,
776 		/*
777 		 * No automatic compensation, compensate each pin
778 		 * independently, proximity hysteresis: 32, close
779 		 * debouncer off, far debouncer off.
780 		 */
781 		.def = 0x00,
782 	},
783 	{
784 		.reg = SX9500_REG_PROX_CTRL8,
785 		/* No stuck timeout, no periodic compensation. */
786 		.def = 0x00,
787 	},
788 	{
789 		.reg = SX9500_REG_PROX_CTRL0,
790 		/* Scan period: 30ms, all sensors disabled. */
791 		.def = 0x00,
792 	},
793 };
794 
795 /* Activate all channels and perform an initial compensation. */
796 static int sx9500_init_compensation(struct iio_dev *indio_dev)
797 {
798 	struct sx9500_data *data = iio_priv(indio_dev);
799 	int i, ret;
800 	unsigned int val;
801 
802 	ret = regmap_update_bits(data->regmap, SX9500_REG_PROX_CTRL0,
803 				 GENMASK(SX9500_NUM_CHANNELS, 0),
804 				 GENMASK(SX9500_NUM_CHANNELS, 0));
805 	if (ret < 0)
806 		return ret;
807 
808 	for (i = 10; i >= 0; i--) {
809 		usleep_range(10000, 20000);
810 		ret = regmap_read(data->regmap, SX9500_REG_STAT, &val);
811 		if (ret < 0)
812 			goto out;
813 		if (!(val & SX9500_COMPSTAT_MASK))
814 			break;
815 	}
816 
817 	if (i < 0) {
818 		dev_err(&data->client->dev, "initial compensation timed out");
819 		ret = -ETIMEDOUT;
820 	}
821 
822 out:
823 	regmap_update_bits(data->regmap, SX9500_REG_PROX_CTRL0,
824 			   GENMASK(SX9500_NUM_CHANNELS, 0), 0);
825 	return ret;
826 }
827 
828 static int sx9500_init_device(struct iio_dev *indio_dev)
829 {
830 	struct sx9500_data *data = iio_priv(indio_dev);
831 	int ret, i;
832 	unsigned int val;
833 
834 	if (data->gpiod_rst) {
835 		gpiod_set_value_cansleep(data->gpiod_rst, 0);
836 		usleep_range(1000, 2000);
837 		gpiod_set_value_cansleep(data->gpiod_rst, 1);
838 		usleep_range(1000, 2000);
839 	}
840 
841 	ret = regmap_write(data->regmap, SX9500_REG_IRQ_MSK, 0);
842 	if (ret < 0)
843 		return ret;
844 
845 	ret = regmap_write(data->regmap, SX9500_REG_RESET,
846 			   SX9500_SOFT_RESET);
847 	if (ret < 0)
848 		return ret;
849 
850 	ret = regmap_read(data->regmap, SX9500_REG_IRQ_SRC, &val);
851 	if (ret < 0)
852 		return ret;
853 
854 	for (i = 0; i < ARRAY_SIZE(sx9500_default_regs); i++) {
855 		ret = regmap_write(data->regmap,
856 				   sx9500_default_regs[i].reg,
857 				   sx9500_default_regs[i].def);
858 		if (ret < 0)
859 			return ret;
860 	}
861 
862 	return sx9500_init_compensation(indio_dev);
863 }
864 
865 static void sx9500_gpio_probe(struct i2c_client *client,
866 			      struct sx9500_data *data)
867 {
868 	struct device *dev;
869 	struct gpio_desc *gpio;
870 
871 	if (!client)
872 		return;
873 
874 	dev = &client->dev;
875 
876 	if (client->irq <= 0) {
877 		gpio = devm_gpiod_get_index(dev, SX9500_GPIO_INT, 0, GPIOD_IN);
878 		if (IS_ERR(gpio))
879 			dev_err(dev, "gpio get irq failed\n");
880 		else
881 			client->irq = gpiod_to_irq(gpio);
882 	}
883 
884 	data->gpiod_rst = devm_gpiod_get_index(dev, SX9500_GPIO_RESET,
885 					       0, GPIOD_OUT_HIGH);
886 	if (IS_ERR(data->gpiod_rst)) {
887 		dev_warn(dev, "gpio get reset pin failed\n");
888 		data->gpiod_rst = NULL;
889 	}
890 }
891 
892 static int sx9500_probe(struct i2c_client *client,
893 			const struct i2c_device_id *id)
894 {
895 	int ret;
896 	struct iio_dev *indio_dev;
897 	struct sx9500_data *data;
898 
899 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
900 	if (indio_dev == NULL)
901 		return -ENOMEM;
902 
903 	data = iio_priv(indio_dev);
904 	data->client = client;
905 	mutex_init(&data->mutex);
906 	init_completion(&data->completion);
907 	data->trigger_enabled = false;
908 
909 	data->regmap = devm_regmap_init_i2c(client, &sx9500_regmap_config);
910 	if (IS_ERR(data->regmap))
911 		return PTR_ERR(data->regmap);
912 
913 	indio_dev->dev.parent = &client->dev;
914 	indio_dev->name = SX9500_DRIVER_NAME;
915 	indio_dev->channels = sx9500_channels;
916 	indio_dev->num_channels = ARRAY_SIZE(sx9500_channels);
917 	indio_dev->info = &sx9500_info;
918 	indio_dev->modes = INDIO_DIRECT_MODE;
919 	i2c_set_clientdata(client, indio_dev);
920 
921 	sx9500_gpio_probe(client, data);
922 
923 	ret = sx9500_init_device(indio_dev);
924 	if (ret < 0)
925 		return ret;
926 
927 	if (client->irq <= 0)
928 		dev_warn(&client->dev, "no valid irq found\n");
929 	else {
930 		ret = devm_request_threaded_irq(&client->dev, client->irq,
931 				sx9500_irq_handler, sx9500_irq_thread_handler,
932 				IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
933 				SX9500_IRQ_NAME, indio_dev);
934 		if (ret < 0)
935 			return ret;
936 
937 		data->trig = devm_iio_trigger_alloc(&client->dev,
938 				"%s-dev%d", indio_dev->name, indio_dev->id);
939 		if (!data->trig)
940 			return -ENOMEM;
941 
942 		data->trig->dev.parent = &client->dev;
943 		data->trig->ops = &sx9500_trigger_ops;
944 		iio_trigger_set_drvdata(data->trig, indio_dev);
945 
946 		ret = iio_trigger_register(data->trig);
947 		if (ret)
948 			return ret;
949 	}
950 
951 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
952 					 sx9500_trigger_handler,
953 					 &sx9500_buffer_setup_ops);
954 	if (ret < 0)
955 		goto out_trigger_unregister;
956 
957 	ret = iio_device_register(indio_dev);
958 	if (ret < 0)
959 		goto out_buffer_cleanup;
960 
961 	return 0;
962 
963 out_buffer_cleanup:
964 	iio_triggered_buffer_cleanup(indio_dev);
965 out_trigger_unregister:
966 	if (client->irq > 0)
967 		iio_trigger_unregister(data->trig);
968 
969 	return ret;
970 }
971 
972 static int sx9500_remove(struct i2c_client *client)
973 {
974 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
975 	struct sx9500_data *data = iio_priv(indio_dev);
976 
977 	iio_device_unregister(indio_dev);
978 	iio_triggered_buffer_cleanup(indio_dev);
979 	if (client->irq > 0)
980 		iio_trigger_unregister(data->trig);
981 	kfree(data->buffer);
982 
983 	return 0;
984 }
985 
986 #ifdef CONFIG_PM_SLEEP
987 static int sx9500_suspend(struct device *dev)
988 {
989 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
990 	struct sx9500_data *data = iio_priv(indio_dev);
991 	int ret;
992 
993 	mutex_lock(&data->mutex);
994 	ret = regmap_read(data->regmap, SX9500_REG_PROX_CTRL0,
995 			  &data->suspend_ctrl0);
996 	if (ret < 0)
997 		goto out;
998 
999 	/*
1000 	 * Scan period doesn't matter because when all the sensors are
1001 	 * deactivated the device is in sleep mode.
1002 	 */
1003 	ret = regmap_write(data->regmap, SX9500_REG_PROX_CTRL0, 0);
1004 
1005 out:
1006 	mutex_unlock(&data->mutex);
1007 	return ret;
1008 }
1009 
1010 static int sx9500_resume(struct device *dev)
1011 {
1012 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1013 	struct sx9500_data *data = iio_priv(indio_dev);
1014 	int ret;
1015 
1016 	mutex_lock(&data->mutex);
1017 	ret = regmap_write(data->regmap, SX9500_REG_PROX_CTRL0,
1018 			   data->suspend_ctrl0);
1019 	mutex_unlock(&data->mutex);
1020 
1021 	return ret;
1022 }
1023 #endif /* CONFIG_PM_SLEEP */
1024 
1025 static const struct dev_pm_ops sx9500_pm_ops = {
1026 	SET_SYSTEM_SLEEP_PM_OPS(sx9500_suspend, sx9500_resume)
1027 };
1028 
1029 static const struct acpi_device_id sx9500_acpi_match[] = {
1030 	{"SSX9500", 0},
1031 	{ },
1032 };
1033 MODULE_DEVICE_TABLE(acpi, sx9500_acpi_match);
1034 
1035 static const struct i2c_device_id sx9500_id[] = {
1036 	{"sx9500", 0},
1037 	{ },
1038 };
1039 MODULE_DEVICE_TABLE(i2c, sx9500_id);
1040 
1041 static struct i2c_driver sx9500_driver = {
1042 	.driver = {
1043 		.name	= SX9500_DRIVER_NAME,
1044 		.acpi_match_table = ACPI_PTR(sx9500_acpi_match),
1045 		.pm = &sx9500_pm_ops,
1046 	},
1047 	.probe		= sx9500_probe,
1048 	.remove		= sx9500_remove,
1049 	.id_table	= sx9500_id,
1050 };
1051 module_i2c_driver(sx9500_driver);
1052 
1053 MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
1054 MODULE_DESCRIPTION("Driver for Semtech SX9500 proximity sensor");
1055 MODULE_LICENSE("GPL v2");
1056