1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Azoteq IQS621/622 Ambient Light Sensors
4 *
5 * Copyright (C) 2019 Jeff LaBundy <jeff@labundy.com>
6 */
7
8#include <linux/device.h>
9#include <linux/iio/events.h>
10#include <linux/iio/iio.h>
11#include <linux/kernel.h>
12#include <linux/mfd/iqs62x.h>
13#include <linux/module.h>
14#include <linux/mutex.h>
15#include <linux/notifier.h>
16#include <linux/platform_device.h>
17#include <linux/regmap.h>
18
19#define IQS621_ALS_FLAGS_LIGHT			BIT(7)
20#define IQS621_ALS_FLAGS_RANGE			GENMASK(3, 0)
21
22#define IQS621_ALS_UI_OUT			0x17
23
24#define IQS621_ALS_THRESH_DARK			0x80
25#define IQS621_ALS_THRESH_LIGHT			0x81
26
27#define IQS622_IR_RANGE				0x15
28#define IQS622_IR_FLAGS				0x16
29#define IQS622_IR_FLAGS_TOUCH			BIT(1)
30#define IQS622_IR_FLAGS_PROX			BIT(0)
31
32#define IQS622_IR_UI_OUT			0x17
33
34#define IQS622_IR_THRESH_PROX			0x91
35#define IQS622_IR_THRESH_TOUCH			0x92
36
37struct iqs621_als_private {
38	struct iqs62x_core *iqs62x;
39	struct iio_dev *indio_dev;
40	struct notifier_block notifier;
41	struct mutex lock;
42	bool light_en;
43	bool range_en;
44	bool prox_en;
45	u8 als_flags;
46	u8 ir_flags_mask;
47	u8 ir_flags;
48	u8 thresh_light;
49	u8 thresh_dark;
50	u8 thresh_prox;
51};
52
53static int iqs621_als_init(struct iqs621_als_private *iqs621_als)
54{
55	struct iqs62x_core *iqs62x = iqs621_als->iqs62x;
56	unsigned int event_mask = 0;
57	int ret;
58
59	switch (iqs621_als->ir_flags_mask) {
60	case IQS622_IR_FLAGS_TOUCH:
61		ret = regmap_write(iqs62x->regmap, IQS622_IR_THRESH_TOUCH,
62				   iqs621_als->thresh_prox);
63		break;
64
65	case IQS622_IR_FLAGS_PROX:
66		ret = regmap_write(iqs62x->regmap, IQS622_IR_THRESH_PROX,
67				   iqs621_als->thresh_prox);
68		break;
69
70	default:
71		ret = regmap_write(iqs62x->regmap, IQS621_ALS_THRESH_LIGHT,
72				   iqs621_als->thresh_light);
73		if (ret)
74			return ret;
75
76		ret = regmap_write(iqs62x->regmap, IQS621_ALS_THRESH_DARK,
77				   iqs621_als->thresh_dark);
78	}
79
80	if (ret)
81		return ret;
82
83	if (iqs621_als->light_en || iqs621_als->range_en)
84		event_mask |= iqs62x->dev_desc->als_mask;
85
86	if (iqs621_als->prox_en)
87		event_mask |= iqs62x->dev_desc->ir_mask;
88
89	return regmap_update_bits(iqs62x->regmap, IQS620_GLBL_EVENT_MASK,
90				  event_mask, 0);
91}
92
93static int iqs621_als_notifier(struct notifier_block *notifier,
94			       unsigned long event_flags, void *context)
95{
96	struct iqs62x_event_data *event_data = context;
97	struct iqs621_als_private *iqs621_als;
98	struct iio_dev *indio_dev;
99	bool light_new, light_old;
100	bool prox_new, prox_old;
101	u8 range_new, range_old;
102	s64 timestamp;
103	int ret;
104
105	iqs621_als = container_of(notifier, struct iqs621_als_private,
106				  notifier);
107	indio_dev = iqs621_als->indio_dev;
108	timestamp = iio_get_time_ns(indio_dev);
109
110	mutex_lock(&iqs621_als->lock);
111
112	if (event_flags & BIT(IQS62X_EVENT_SYS_RESET)) {
113		ret = iqs621_als_init(iqs621_als);
114		if (ret) {
115			dev_err(indio_dev->dev.parent,
116				"Failed to re-initialize device: %d\n", ret);
117			ret = NOTIFY_BAD;
118		} else {
119			ret = NOTIFY_OK;
120		}
121
122		goto err_mutex;
123	}
124
125	if (!iqs621_als->light_en && !iqs621_als->range_en &&
126	    !iqs621_als->prox_en) {
127		ret = NOTIFY_DONE;
128		goto err_mutex;
129	}
130
131	/* IQS621 only */
132	light_new = event_data->als_flags & IQS621_ALS_FLAGS_LIGHT;
133	light_old = iqs621_als->als_flags & IQS621_ALS_FLAGS_LIGHT;
134
135	if (iqs621_als->light_en && light_new && !light_old)
136		iio_push_event(indio_dev,
137			       IIO_UNMOD_EVENT_CODE(IIO_LIGHT, 0,
138						    IIO_EV_TYPE_THRESH,
139						    IIO_EV_DIR_RISING),
140			       timestamp);
141	else if (iqs621_als->light_en && !light_new && light_old)
142		iio_push_event(indio_dev,
143			       IIO_UNMOD_EVENT_CODE(IIO_LIGHT, 0,
144						    IIO_EV_TYPE_THRESH,
145						    IIO_EV_DIR_FALLING),
146			       timestamp);
147
148	/* IQS621 and IQS622 */
149	range_new = event_data->als_flags & IQS621_ALS_FLAGS_RANGE;
150	range_old = iqs621_als->als_flags & IQS621_ALS_FLAGS_RANGE;
151
152	if (iqs621_als->range_en && (range_new > range_old))
153		iio_push_event(indio_dev,
154			       IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0,
155						    IIO_EV_TYPE_CHANGE,
156						    IIO_EV_DIR_RISING),
157			       timestamp);
158	else if (iqs621_als->range_en && (range_new < range_old))
159		iio_push_event(indio_dev,
160			       IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0,
161						    IIO_EV_TYPE_CHANGE,
162						    IIO_EV_DIR_FALLING),
163			       timestamp);
164
165	/* IQS622 only */
166	prox_new = event_data->ir_flags & iqs621_als->ir_flags_mask;
167	prox_old = iqs621_als->ir_flags & iqs621_als->ir_flags_mask;
168
169	if (iqs621_als->prox_en && prox_new && !prox_old)
170		iio_push_event(indio_dev,
171			       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 0,
172						    IIO_EV_TYPE_THRESH,
173						    IIO_EV_DIR_RISING),
174			       timestamp);
175	else if (iqs621_als->prox_en && !prox_new && prox_old)
176		iio_push_event(indio_dev,
177			       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 0,
178						    IIO_EV_TYPE_THRESH,
179						    IIO_EV_DIR_FALLING),
180			       timestamp);
181
182	iqs621_als->als_flags = event_data->als_flags;
183	iqs621_als->ir_flags = event_data->ir_flags;
184	ret = NOTIFY_OK;
185
186err_mutex:
187	mutex_unlock(&iqs621_als->lock);
188
189	return ret;
190}
191
192static void iqs621_als_notifier_unregister(void *context)
193{
194	struct iqs621_als_private *iqs621_als = context;
195	struct iio_dev *indio_dev = iqs621_als->indio_dev;
196	int ret;
197
198	ret = blocking_notifier_chain_unregister(&iqs621_als->iqs62x->nh,
199						 &iqs621_als->notifier);
200	if (ret)
201		dev_err(indio_dev->dev.parent,
202			"Failed to unregister notifier: %d\n", ret);
203}
204
205static int iqs621_als_read_raw(struct iio_dev *indio_dev,
206			       struct iio_chan_spec const *chan,
207			       int *val, int *val2, long mask)
208{
209	struct iqs621_als_private *iqs621_als = iio_priv(indio_dev);
210	struct iqs62x_core *iqs62x = iqs621_als->iqs62x;
211	int ret;
212	__le16 val_buf;
213
214	switch (chan->type) {
215	case IIO_INTENSITY:
216		ret = regmap_read(iqs62x->regmap, chan->address, val);
217		if (ret)
218			return ret;
219
220		*val &= IQS621_ALS_FLAGS_RANGE;
221		return IIO_VAL_INT;
222
223	case IIO_PROXIMITY:
224	case IIO_LIGHT:
225		ret = regmap_raw_read(iqs62x->regmap, chan->address, &val_buf,
226				      sizeof(val_buf));
227		if (ret)
228			return ret;
229
230		*val = le16_to_cpu(val_buf);
231		return IIO_VAL_INT;
232
233	default:
234		return -EINVAL;
235	}
236}
237
238static int iqs621_als_read_event_config(struct iio_dev *indio_dev,
239					const struct iio_chan_spec *chan,
240					enum iio_event_type type,
241					enum iio_event_direction dir)
242{
243	struct iqs621_als_private *iqs621_als = iio_priv(indio_dev);
244	int ret;
245
246	mutex_lock(&iqs621_als->lock);
247
248	switch (chan->type) {
249	case IIO_LIGHT:
250		ret = iqs621_als->light_en;
251		break;
252
253	case IIO_INTENSITY:
254		ret = iqs621_als->range_en;
255		break;
256
257	case IIO_PROXIMITY:
258		ret = iqs621_als->prox_en;
259		break;
260
261	default:
262		ret = -EINVAL;
263	}
264
265	mutex_unlock(&iqs621_als->lock);
266
267	return ret;
268}
269
270static int iqs621_als_write_event_config(struct iio_dev *indio_dev,
271					 const struct iio_chan_spec *chan,
272					 enum iio_event_type type,
273					 enum iio_event_direction dir,
274					 int state)
275{
276	struct iqs621_als_private *iqs621_als = iio_priv(indio_dev);
277	struct iqs62x_core *iqs62x = iqs621_als->iqs62x;
278	unsigned int val;
279	int ret;
280
281	mutex_lock(&iqs621_als->lock);
282
283	ret = regmap_read(iqs62x->regmap, iqs62x->dev_desc->als_flags, &val);
284	if (ret)
285		goto err_mutex;
286	iqs621_als->als_flags = val;
287
288	switch (chan->type) {
289	case IIO_LIGHT:
290		ret = regmap_update_bits(iqs62x->regmap, IQS620_GLBL_EVENT_MASK,
291					 iqs62x->dev_desc->als_mask,
292					 iqs621_als->range_en || state ? 0 :
293									 0xFF);
294		if (!ret)
295			iqs621_als->light_en = state;
296		break;
297
298	case IIO_INTENSITY:
299		ret = regmap_update_bits(iqs62x->regmap, IQS620_GLBL_EVENT_MASK,
300					 iqs62x->dev_desc->als_mask,
301					 iqs621_als->light_en || state ? 0 :
302									 0xFF);
303		if (!ret)
304			iqs621_als->range_en = state;
305		break;
306
307	case IIO_PROXIMITY:
308		ret = regmap_read(iqs62x->regmap, IQS622_IR_FLAGS, &val);
309		if (ret)
310			goto err_mutex;
311		iqs621_als->ir_flags = val;
312
313		ret = regmap_update_bits(iqs62x->regmap, IQS620_GLBL_EVENT_MASK,
314					 iqs62x->dev_desc->ir_mask,
315					 state ? 0 : 0xFF);
316		if (!ret)
317			iqs621_als->prox_en = state;
318		break;
319
320	default:
321		ret = -EINVAL;
322	}
323
324err_mutex:
325	mutex_unlock(&iqs621_als->lock);
326
327	return ret;
328}
329
330static int iqs621_als_read_event_value(struct iio_dev *indio_dev,
331				       const struct iio_chan_spec *chan,
332				       enum iio_event_type type,
333				       enum iio_event_direction dir,
334				       enum iio_event_info info,
335				       int *val, int *val2)
336{
337	struct iqs621_als_private *iqs621_als = iio_priv(indio_dev);
338	int ret = IIO_VAL_INT;
339
340	mutex_lock(&iqs621_als->lock);
341
342	switch (dir) {
343	case IIO_EV_DIR_RISING:
344		*val = iqs621_als->thresh_light * 16;
345		break;
346
347	case IIO_EV_DIR_FALLING:
348		*val = iqs621_als->thresh_dark * 4;
349		break;
350
351	case IIO_EV_DIR_EITHER:
352		if (iqs621_als->ir_flags_mask == IQS622_IR_FLAGS_TOUCH)
353			*val = iqs621_als->thresh_prox * 4;
354		else
355			*val = iqs621_als->thresh_prox;
356		break;
357
358	default:
359		ret = -EINVAL;
360	}
361
362	mutex_unlock(&iqs621_als->lock);
363
364	return ret;
365}
366
367static int iqs621_als_write_event_value(struct iio_dev *indio_dev,
368					const struct iio_chan_spec *chan,
369					enum iio_event_type type,
370					enum iio_event_direction dir,
371					enum iio_event_info info,
372					int val, int val2)
373{
374	struct iqs621_als_private *iqs621_als = iio_priv(indio_dev);
375	struct iqs62x_core *iqs62x = iqs621_als->iqs62x;
376	unsigned int thresh_reg, thresh_val;
377	u8 ir_flags_mask, *thresh_cache;
378	int ret = -EINVAL;
379
380	mutex_lock(&iqs621_als->lock);
381
382	switch (dir) {
383	case IIO_EV_DIR_RISING:
384		thresh_reg = IQS621_ALS_THRESH_LIGHT;
385		thresh_val = val / 16;
386
387		thresh_cache = &iqs621_als->thresh_light;
388		ir_flags_mask = 0;
389		break;
390
391	case IIO_EV_DIR_FALLING:
392		thresh_reg = IQS621_ALS_THRESH_DARK;
393		thresh_val = val / 4;
394
395		thresh_cache = &iqs621_als->thresh_dark;
396		ir_flags_mask = 0;
397		break;
398
399	case IIO_EV_DIR_EITHER:
400		/*
401		 * The IQS622 supports two detection thresholds, both measured
402		 * in the same arbitrary units reported by read_raw: proximity
403		 * (0 through 255 in steps of 1), and touch (0 through 1020 in
404		 * steps of 4).
405		 *
406		 * Based on the single detection threshold chosen by the user,
407		 * select the hardware threshold that gives the best trade-off
408		 * between range and resolution.
409		 *
410		 * By default, the close-range (but coarse) touch threshold is
411		 * chosen during probe.
412		 */
413		switch (val) {
414		case 0 ... 255:
415			thresh_reg = IQS622_IR_THRESH_PROX;
416			thresh_val = val;
417
418			ir_flags_mask = IQS622_IR_FLAGS_PROX;
419			break;
420
421		case 256 ... 1020:
422			thresh_reg = IQS622_IR_THRESH_TOUCH;
423			thresh_val = val / 4;
424
425			ir_flags_mask = IQS622_IR_FLAGS_TOUCH;
426			break;
427
428		default:
429			goto err_mutex;
430		}
431
432		thresh_cache = &iqs621_als->thresh_prox;
433		break;
434
435	default:
436		goto err_mutex;
437	}
438
439	if (thresh_val > 0xFF)
440		goto err_mutex;
441
442	ret = regmap_write(iqs62x->regmap, thresh_reg, thresh_val);
443	if (ret)
444		goto err_mutex;
445
446	*thresh_cache = thresh_val;
447	iqs621_als->ir_flags_mask = ir_flags_mask;
448
449err_mutex:
450	mutex_unlock(&iqs621_als->lock);
451
452	return ret;
453}
454
455static const struct iio_info iqs621_als_info = {
456	.read_raw = &iqs621_als_read_raw,
457	.read_event_config = iqs621_als_read_event_config,
458	.write_event_config = iqs621_als_write_event_config,
459	.read_event_value = iqs621_als_read_event_value,
460	.write_event_value = iqs621_als_write_event_value,
461};
462
463static const struct iio_event_spec iqs621_als_range_events[] = {
464	{
465		.type = IIO_EV_TYPE_CHANGE,
466		.dir = IIO_EV_DIR_EITHER,
467		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
468	},
469};
470
471static const struct iio_event_spec iqs621_als_light_events[] = {
472	{
473		.type = IIO_EV_TYPE_THRESH,
474		.dir = IIO_EV_DIR_EITHER,
475		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
476	},
477	{
478		.type = IIO_EV_TYPE_THRESH,
479		.dir = IIO_EV_DIR_RISING,
480		.mask_separate = BIT(IIO_EV_INFO_VALUE),
481	},
482	{
483		.type = IIO_EV_TYPE_THRESH,
484		.dir = IIO_EV_DIR_FALLING,
485		.mask_separate = BIT(IIO_EV_INFO_VALUE),
486	},
487};
488
489static const struct iio_chan_spec iqs621_als_channels[] = {
490	{
491		.type = IIO_INTENSITY,
492		.address = IQS621_ALS_FLAGS,
493		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
494		.event_spec = iqs621_als_range_events,
495		.num_event_specs = ARRAY_SIZE(iqs621_als_range_events),
496	},
497	{
498		.type = IIO_LIGHT,
499		.address = IQS621_ALS_UI_OUT,
500		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
501		.event_spec = iqs621_als_light_events,
502		.num_event_specs = ARRAY_SIZE(iqs621_als_light_events),
503	},
504};
505
506static const struct iio_event_spec iqs622_als_prox_events[] = {
507	{
508		.type = IIO_EV_TYPE_THRESH,
509		.dir = IIO_EV_DIR_EITHER,
510		.mask_separate = BIT(IIO_EV_INFO_ENABLE) |
511				 BIT(IIO_EV_INFO_VALUE),
512	},
513};
514
515static const struct iio_chan_spec iqs622_als_channels[] = {
516	{
517		.type = IIO_INTENSITY,
518		.channel2 = IIO_MOD_LIGHT_BOTH,
519		.address = IQS622_ALS_FLAGS,
520		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
521		.event_spec = iqs621_als_range_events,
522		.num_event_specs = ARRAY_SIZE(iqs621_als_range_events),
523		.modified = true,
524	},
525	{
526		.type = IIO_INTENSITY,
527		.channel2 = IIO_MOD_LIGHT_IR,
528		.address = IQS622_IR_RANGE,
529		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
530		.modified = true,
531	},
532	{
533		.type = IIO_PROXIMITY,
534		.address = IQS622_IR_UI_OUT,
535		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
536		.event_spec = iqs622_als_prox_events,
537		.num_event_specs = ARRAY_SIZE(iqs622_als_prox_events),
538	},
539};
540
541static int iqs621_als_probe(struct platform_device *pdev)
542{
543	struct iqs62x_core *iqs62x = dev_get_drvdata(pdev->dev.parent);
544	struct iqs621_als_private *iqs621_als;
545	struct iio_dev *indio_dev;
546	unsigned int val;
547	int ret;
548
549	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*iqs621_als));
550	if (!indio_dev)
551		return -ENOMEM;
552
553	iqs621_als = iio_priv(indio_dev);
554	iqs621_als->iqs62x = iqs62x;
555	iqs621_als->indio_dev = indio_dev;
556
557	if (iqs62x->dev_desc->prod_num == IQS622_PROD_NUM) {
558		ret = regmap_read(iqs62x->regmap, IQS622_IR_THRESH_TOUCH,
559				  &val);
560		if (ret)
561			return ret;
562		iqs621_als->thresh_prox = val;
563		iqs621_als->ir_flags_mask = IQS622_IR_FLAGS_TOUCH;
564
565		indio_dev->channels = iqs622_als_channels;
566		indio_dev->num_channels = ARRAY_SIZE(iqs622_als_channels);
567	} else {
568		ret = regmap_read(iqs62x->regmap, IQS621_ALS_THRESH_LIGHT,
569				  &val);
570		if (ret)
571			return ret;
572		iqs621_als->thresh_light = val;
573
574		ret = regmap_read(iqs62x->regmap, IQS621_ALS_THRESH_DARK,
575				  &val);
576		if (ret)
577			return ret;
578		iqs621_als->thresh_dark = val;
579
580		indio_dev->channels = iqs621_als_channels;
581		indio_dev->num_channels = ARRAY_SIZE(iqs621_als_channels);
582	}
583
584	indio_dev->modes = INDIO_DIRECT_MODE;
585	indio_dev->name = iqs62x->dev_desc->dev_name;
586	indio_dev->info = &iqs621_als_info;
587
588	mutex_init(&iqs621_als->lock);
589
590	iqs621_als->notifier.notifier_call = iqs621_als_notifier;
591	ret = blocking_notifier_chain_register(&iqs621_als->iqs62x->nh,
592					       &iqs621_als->notifier);
593	if (ret) {
594		dev_err(&pdev->dev, "Failed to register notifier: %d\n", ret);
595		return ret;
596	}
597
598	ret = devm_add_action_or_reset(&pdev->dev,
599				       iqs621_als_notifier_unregister,
600				       iqs621_als);
601	if (ret)
602		return ret;
603
604	return devm_iio_device_register(&pdev->dev, indio_dev);
605}
606
607static struct platform_driver iqs621_als_platform_driver = {
608	.driver = {
609		.name = "iqs621-als",
610	},
611	.probe = iqs621_als_probe,
612};
613module_platform_driver(iqs621_als_platform_driver);
614
615MODULE_AUTHOR("Jeff LaBundy <jeff@labundy.com>");
616MODULE_DESCRIPTION("Azoteq IQS621/622 Ambient Light Sensors");
617MODULE_LICENSE("GPL");
618MODULE_ALIAS("platform:iqs621-als");
619