1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ADS1015 - Texas Instruments Analog-to-Digital Converter
4  *
5  * Copyright (c) 2016, Intel Corporation.
6  *
7  * IIO driver for ADS1015 ADC 7-bit I2C slave address:
8  *	* 0x48 - ADDR connected to Ground
9  *	* 0x49 - ADDR connected to Vdd
10  *	* 0x4A - ADDR connected to SDA
11  *	* 0x4B - ADDR connected to SCL
12  */
13 
14 #include <linux/module.h>
15 #include <linux/cleanup.h>
16 #include <linux/init.h>
17 #include <linux/irq.h>
18 #include <linux/i2c.h>
19 #include <linux/property.h>
20 #include <linux/regmap.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/mutex.h>
23 #include <linux/delay.h>
24 
25 #include <linux/iio/iio.h>
26 #include <linux/iio/types.h>
27 #include <linux/iio/sysfs.h>
28 #include <linux/iio/events.h>
29 #include <linux/iio/buffer.h>
30 #include <linux/iio/triggered_buffer.h>
31 #include <linux/iio/trigger_consumer.h>
32 
33 #define ADS1015_DRV_NAME "ads1015"
34 
35 #define ADS1015_CHANNELS 8
36 
37 #define ADS1015_CONV_REG	0x00
38 #define ADS1015_CFG_REG		0x01
39 #define ADS1015_LO_THRESH_REG	0x02
40 #define ADS1015_HI_THRESH_REG	0x03
41 
42 #define ADS1015_CFG_COMP_QUE_SHIFT	0
43 #define ADS1015_CFG_COMP_LAT_SHIFT	2
44 #define ADS1015_CFG_COMP_POL_SHIFT	3
45 #define ADS1015_CFG_COMP_MODE_SHIFT	4
46 #define ADS1015_CFG_DR_SHIFT	5
47 #define ADS1015_CFG_MOD_SHIFT	8
48 #define ADS1015_CFG_PGA_SHIFT	9
49 #define ADS1015_CFG_MUX_SHIFT	12
50 
51 #define ADS1015_CFG_COMP_QUE_MASK	GENMASK(1, 0)
52 #define ADS1015_CFG_COMP_LAT_MASK	BIT(2)
53 #define ADS1015_CFG_COMP_POL_MASK	BIT(3)
54 #define ADS1015_CFG_COMP_MODE_MASK	BIT(4)
55 #define ADS1015_CFG_DR_MASK	GENMASK(7, 5)
56 #define ADS1015_CFG_MOD_MASK	BIT(8)
57 #define ADS1015_CFG_PGA_MASK	GENMASK(11, 9)
58 #define ADS1015_CFG_MUX_MASK	GENMASK(14, 12)
59 
60 /* Comparator queue and disable field */
61 #define ADS1015_CFG_COMP_DISABLE	3
62 
63 /* Comparator polarity field */
64 #define ADS1015_CFG_COMP_POL_LOW	0
65 #define ADS1015_CFG_COMP_POL_HIGH	1
66 
67 /* Comparator mode field */
68 #define ADS1015_CFG_COMP_MODE_TRAD	0
69 #define ADS1015_CFG_COMP_MODE_WINDOW	1
70 
71 /* device operating modes */
72 #define ADS1015_CONTINUOUS	0
73 #define ADS1015_SINGLESHOT	1
74 
75 #define ADS1015_SLEEP_DELAY_MS		2000
76 #define ADS1015_DEFAULT_PGA		2
77 #define ADS1015_DEFAULT_DATA_RATE	4
78 #define ADS1015_DEFAULT_CHAN		0
79 
80 struct ads1015_chip_data {
81 	struct iio_chan_spec const	*channels;
82 	int				num_channels;
83 	const struct iio_info		*info;
84 	const int			*data_rate;
85 	const int			data_rate_len;
86 	const int			*scale;
87 	const int			scale_len;
88 	bool				has_comparator;
89 };
90 
91 enum ads1015_channels {
92 	ADS1015_AIN0_AIN1 = 0,
93 	ADS1015_AIN0_AIN3,
94 	ADS1015_AIN1_AIN3,
95 	ADS1015_AIN2_AIN3,
96 	ADS1015_AIN0,
97 	ADS1015_AIN1,
98 	ADS1015_AIN2,
99 	ADS1015_AIN3,
100 	ADS1015_TIMESTAMP,
101 };
102 
103 static const int ads1015_data_rate[] = {
104 	128, 250, 490, 920, 1600, 2400, 3300, 3300
105 };
106 
107 static const int ads1115_data_rate[] = {
108 	8, 16, 32, 64, 128, 250, 475, 860
109 };
110 
111 /*
112  * Translation from PGA bits to full-scale positive and negative input voltage
113  * range in mV
114  */
115 static const int ads1015_fullscale_range[] = {
116 	6144, 4096, 2048, 1024, 512, 256, 256, 256
117 };
118 
119 static const int ads1015_scale[] = {	/* 12bit ADC */
120 	256, 11,
121 	512, 11,
122 	1024, 11,
123 	2048, 11,
124 	4096, 11,
125 	6144, 11
126 };
127 
128 static const int ads1115_scale[] = {	/* 16bit ADC */
129 	256, 15,
130 	512, 15,
131 	1024, 15,
132 	2048, 15,
133 	4096, 15,
134 	6144, 15
135 };
136 
137 /*
138  * Translation from COMP_QUE field value to the number of successive readings
139  * exceed the threshold values before an interrupt is generated
140  */
141 static const int ads1015_comp_queue[] = { 1, 2, 4 };
142 
143 static const struct iio_event_spec ads1015_events[] = {
144 	{
145 		.type = IIO_EV_TYPE_THRESH,
146 		.dir = IIO_EV_DIR_RISING,
147 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
148 				BIT(IIO_EV_INFO_ENABLE),
149 	}, {
150 		.type = IIO_EV_TYPE_THRESH,
151 		.dir = IIO_EV_DIR_FALLING,
152 		.mask_separate = BIT(IIO_EV_INFO_VALUE),
153 	}, {
154 		.type = IIO_EV_TYPE_THRESH,
155 		.dir = IIO_EV_DIR_EITHER,
156 		.mask_separate = BIT(IIO_EV_INFO_ENABLE) |
157 				BIT(IIO_EV_INFO_PERIOD),
158 	},
159 };
160 
161 /*
162  * Compile-time check whether _fitbits can accommodate up to _testbits
163  * bits. Returns _fitbits on success, fails to compile otherwise.
164  *
165  * The test works such that it multiplies constant _fitbits by constant
166  * double-negation of size of a non-empty structure, i.e. it multiplies
167  * constant _fitbits by constant 1 in each successful compilation case.
168  * The non-empty structure may contain C11 _Static_assert(), make use of
169  * this and place the kernel variant of static assert in there, so that
170  * it performs the compile-time check for _testbits <= _fitbits. Note
171  * that it is not possible to directly use static_assert in compound
172  * statements, hence this convoluted construct.
173  */
174 #define FIT_CHECK(_testbits, _fitbits)					\
175 	(								\
176 		(_fitbits) *						\
177 		!!sizeof(struct {					\
178 			static_assert((_testbits) <= (_fitbits));	\
179 			int pad;					\
180 		})							\
181 	)
182 
183 #define ADS1015_V_CHAN(_chan, _addr, _realbits, _shift, _event_spec, _num_event_specs) { \
184 	.type = IIO_VOLTAGE,					\
185 	.indexed = 1,						\
186 	.address = _addr,					\
187 	.channel = _chan,					\
188 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
189 				BIT(IIO_CHAN_INFO_SCALE) |	\
190 				BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
191 	.info_mask_shared_by_all_available =			\
192 				BIT(IIO_CHAN_INFO_SCALE) |	\
193 				BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
194 	.scan_index = _addr,					\
195 	.scan_type = {						\
196 		.sign = 's',					\
197 		.realbits = (_realbits),			\
198 		.storagebits = FIT_CHECK((_realbits) + (_shift), 16),	\
199 		.shift = (_shift),				\
200 		.endianness = IIO_CPU,				\
201 	},							\
202 	.event_spec = (_event_spec),				\
203 	.num_event_specs = (_num_event_specs),			\
204 	.datasheet_name = "AIN"#_chan,				\
205 }
206 
207 #define ADS1015_V_DIFF_CHAN(_chan, _chan2, _addr, _realbits, _shift, _event_spec, _num_event_specs) { \
208 	.type = IIO_VOLTAGE,					\
209 	.differential = 1,					\
210 	.indexed = 1,						\
211 	.address = _addr,					\
212 	.channel = _chan,					\
213 	.channel2 = _chan2,					\
214 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
215 				BIT(IIO_CHAN_INFO_SCALE) |	\
216 				BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
217 	.info_mask_shared_by_all_available =			\
218 				BIT(IIO_CHAN_INFO_SCALE) |	\
219 				BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
220 	.scan_index = _addr,					\
221 	.scan_type = {						\
222 		.sign = 's',					\
223 		.realbits = (_realbits),			\
224 		.storagebits = FIT_CHECK((_realbits) + (_shift), 16),	\
225 		.shift = (_shift),				\
226 		.endianness = IIO_CPU,				\
227 	},							\
228 	.event_spec = (_event_spec),				\
229 	.num_event_specs = (_num_event_specs),			\
230 	.datasheet_name = "AIN"#_chan"-AIN"#_chan2,		\
231 }
232 
233 struct ads1015_channel_data {
234 	bool enabled;
235 	unsigned int pga;
236 	unsigned int data_rate;
237 };
238 
239 struct ads1015_thresh_data {
240 	unsigned int comp_queue;
241 	int high_thresh;
242 	int low_thresh;
243 };
244 
245 struct ads1015_data {
246 	struct regmap *regmap;
247 	/*
248 	 * Protects ADC ops, e.g: concurrent sysfs/buffered
249 	 * data reads, configuration updates
250 	 */
251 	struct mutex lock;
252 	struct ads1015_channel_data channel_data[ADS1015_CHANNELS];
253 
254 	unsigned int event_channel;
255 	unsigned int comp_mode;
256 	struct ads1015_thresh_data thresh_data[ADS1015_CHANNELS];
257 
258 	const struct ads1015_chip_data *chip;
259 	/*
260 	 * Set to true when the ADC is switched to the continuous-conversion
261 	 * mode and exits from a power-down state.  This flag is used to avoid
262 	 * getting the stale result from the conversion register.
263 	 */
264 	bool conv_invalid;
265 };
266 
267 static bool ads1015_event_channel_enabled(struct ads1015_data *data)
268 {
269 	return (data->event_channel != ADS1015_CHANNELS);
270 }
271 
272 static void ads1015_event_channel_enable(struct ads1015_data *data, int chan,
273 					 int comp_mode)
274 {
275 	WARN_ON(ads1015_event_channel_enabled(data));
276 
277 	data->event_channel = chan;
278 	data->comp_mode = comp_mode;
279 }
280 
281 static void ads1015_event_channel_disable(struct ads1015_data *data, int chan)
282 {
283 	data->event_channel = ADS1015_CHANNELS;
284 }
285 
286 static const struct regmap_range ads1015_writeable_ranges[] = {
287 	regmap_reg_range(ADS1015_CFG_REG, ADS1015_HI_THRESH_REG),
288 };
289 
290 static const struct regmap_access_table ads1015_writeable_table = {
291 	.yes_ranges = ads1015_writeable_ranges,
292 	.n_yes_ranges = ARRAY_SIZE(ads1015_writeable_ranges),
293 };
294 
295 static const struct regmap_config ads1015_regmap_config = {
296 	.reg_bits = 8,
297 	.val_bits = 16,
298 	.max_register = ADS1015_HI_THRESH_REG,
299 	.wr_table = &ads1015_writeable_table,
300 };
301 
302 static const struct regmap_range tla2024_writeable_ranges[] = {
303 	regmap_reg_range(ADS1015_CFG_REG, ADS1015_CFG_REG),
304 };
305 
306 static const struct regmap_access_table tla2024_writeable_table = {
307 	.yes_ranges = tla2024_writeable_ranges,
308 	.n_yes_ranges = ARRAY_SIZE(tla2024_writeable_ranges),
309 };
310 
311 static const struct regmap_config tla2024_regmap_config = {
312 	.reg_bits = 8,
313 	.val_bits = 16,
314 	.max_register = ADS1015_CFG_REG,
315 	.wr_table = &tla2024_writeable_table,
316 };
317 
318 static const struct iio_chan_spec ads1015_channels[] = {
319 	ADS1015_V_DIFF_CHAN(0, 1, ADS1015_AIN0_AIN1, 12, 4,
320 			    ads1015_events, ARRAY_SIZE(ads1015_events)),
321 	ADS1015_V_DIFF_CHAN(0, 3, ADS1015_AIN0_AIN3, 12, 4,
322 			    ads1015_events, ARRAY_SIZE(ads1015_events)),
323 	ADS1015_V_DIFF_CHAN(1, 3, ADS1015_AIN1_AIN3, 12, 4,
324 			    ads1015_events, ARRAY_SIZE(ads1015_events)),
325 	ADS1015_V_DIFF_CHAN(2, 3, ADS1015_AIN2_AIN3, 12, 4,
326 			    ads1015_events, ARRAY_SIZE(ads1015_events)),
327 	ADS1015_V_CHAN(0, ADS1015_AIN0, 12, 4,
328 		       ads1015_events, ARRAY_SIZE(ads1015_events)),
329 	ADS1015_V_CHAN(1, ADS1015_AIN1, 12, 4,
330 		       ads1015_events, ARRAY_SIZE(ads1015_events)),
331 	ADS1015_V_CHAN(2, ADS1015_AIN2, 12, 4,
332 		       ads1015_events, ARRAY_SIZE(ads1015_events)),
333 	ADS1015_V_CHAN(3, ADS1015_AIN3, 12, 4,
334 		       ads1015_events, ARRAY_SIZE(ads1015_events)),
335 	IIO_CHAN_SOFT_TIMESTAMP(ADS1015_TIMESTAMP),
336 };
337 
338 static const struct iio_chan_spec ads1115_channels[] = {
339 	ADS1015_V_DIFF_CHAN(0, 1, ADS1015_AIN0_AIN1, 16, 0,
340 			    ads1015_events, ARRAY_SIZE(ads1015_events)),
341 	ADS1015_V_DIFF_CHAN(0, 3, ADS1015_AIN0_AIN3, 16, 0,
342 			    ads1015_events, ARRAY_SIZE(ads1015_events)),
343 	ADS1015_V_DIFF_CHAN(1, 3, ADS1015_AIN1_AIN3, 16, 0,
344 			    ads1015_events, ARRAY_SIZE(ads1015_events)),
345 	ADS1015_V_DIFF_CHAN(2, 3, ADS1015_AIN2_AIN3, 16, 0,
346 			    ads1015_events, ARRAY_SIZE(ads1015_events)),
347 	ADS1015_V_CHAN(0, ADS1015_AIN0, 16, 0,
348 		       ads1015_events, ARRAY_SIZE(ads1015_events)),
349 	ADS1015_V_CHAN(1, ADS1015_AIN1, 16, 0,
350 		       ads1015_events, ARRAY_SIZE(ads1015_events)),
351 	ADS1015_V_CHAN(2, ADS1015_AIN2, 16, 0,
352 		       ads1015_events, ARRAY_SIZE(ads1015_events)),
353 	ADS1015_V_CHAN(3, ADS1015_AIN3, 16, 0,
354 		       ads1015_events, ARRAY_SIZE(ads1015_events)),
355 	IIO_CHAN_SOFT_TIMESTAMP(ADS1015_TIMESTAMP),
356 };
357 
358 static const struct iio_chan_spec tla2024_channels[] = {
359 	ADS1015_V_DIFF_CHAN(0, 1, ADS1015_AIN0_AIN1, 12, 4, NULL, 0),
360 	ADS1015_V_DIFF_CHAN(0, 3, ADS1015_AIN0_AIN3, 12, 4, NULL, 0),
361 	ADS1015_V_DIFF_CHAN(1, 3, ADS1015_AIN1_AIN3, 12, 4, NULL, 0),
362 	ADS1015_V_DIFF_CHAN(2, 3, ADS1015_AIN2_AIN3, 12, 4, NULL, 0),
363 	ADS1015_V_CHAN(0, ADS1015_AIN0, 12, 4, NULL, 0),
364 	ADS1015_V_CHAN(1, ADS1015_AIN1, 12, 4, NULL, 0),
365 	ADS1015_V_CHAN(2, ADS1015_AIN2, 12, 4, NULL, 0),
366 	ADS1015_V_CHAN(3, ADS1015_AIN3, 12, 4, NULL, 0),
367 	IIO_CHAN_SOFT_TIMESTAMP(ADS1015_TIMESTAMP),
368 };
369 
370 
371 #ifdef CONFIG_PM
372 static int ads1015_set_power_state(struct ads1015_data *data, bool on)
373 {
374 	int ret;
375 	struct device *dev = regmap_get_device(data->regmap);
376 
377 	if (on) {
378 		ret = pm_runtime_resume_and_get(dev);
379 	} else {
380 		pm_runtime_mark_last_busy(dev);
381 		ret = pm_runtime_put_autosuspend(dev);
382 	}
383 
384 	return ret < 0 ? ret : 0;
385 }
386 
387 #else /* !CONFIG_PM */
388 
389 static int ads1015_set_power_state(struct ads1015_data *data, bool on)
390 {
391 	return 0;
392 }
393 
394 #endif /* !CONFIG_PM */
395 
396 static
397 int ads1015_get_adc_result(struct ads1015_data *data, int chan, int *val)
398 {
399 	const int *data_rate = data->chip->data_rate;
400 	int ret, pga, dr, dr_old, conv_time;
401 	unsigned int old, mask, cfg;
402 
403 	if (chan < 0 || chan >= ADS1015_CHANNELS)
404 		return -EINVAL;
405 
406 	ret = regmap_read(data->regmap, ADS1015_CFG_REG, &old);
407 	if (ret)
408 		return ret;
409 
410 	pga = data->channel_data[chan].pga;
411 	dr = data->channel_data[chan].data_rate;
412 	mask = ADS1015_CFG_MUX_MASK | ADS1015_CFG_PGA_MASK |
413 		ADS1015_CFG_DR_MASK;
414 	cfg = chan << ADS1015_CFG_MUX_SHIFT | pga << ADS1015_CFG_PGA_SHIFT |
415 		dr << ADS1015_CFG_DR_SHIFT;
416 
417 	if (ads1015_event_channel_enabled(data)) {
418 		mask |= ADS1015_CFG_COMP_QUE_MASK | ADS1015_CFG_COMP_MODE_MASK;
419 		cfg |= data->thresh_data[chan].comp_queue <<
420 				ADS1015_CFG_COMP_QUE_SHIFT |
421 			data->comp_mode <<
422 				ADS1015_CFG_COMP_MODE_SHIFT;
423 	}
424 
425 	cfg = (old & ~mask) | (cfg & mask);
426 	if (old != cfg) {
427 		ret = regmap_write(data->regmap, ADS1015_CFG_REG, cfg);
428 		if (ret)
429 			return ret;
430 		data->conv_invalid = true;
431 	}
432 	if (data->conv_invalid) {
433 		dr_old = (old & ADS1015_CFG_DR_MASK) >> ADS1015_CFG_DR_SHIFT;
434 		conv_time = DIV_ROUND_UP(USEC_PER_SEC, data_rate[dr_old]);
435 		conv_time += DIV_ROUND_UP(USEC_PER_SEC, data_rate[dr]);
436 		conv_time += conv_time / 10; /* 10% internal clock inaccuracy */
437 		usleep_range(conv_time, conv_time + 1);
438 		data->conv_invalid = false;
439 	}
440 
441 	return regmap_read(data->regmap, ADS1015_CONV_REG, val);
442 }
443 
444 static irqreturn_t ads1015_trigger_handler(int irq, void *p)
445 {
446 	struct iio_poll_func *pf = p;
447 	struct iio_dev *indio_dev = pf->indio_dev;
448 	struct ads1015_data *data = iio_priv(indio_dev);
449 	/* Ensure natural alignment of timestamp */
450 	struct {
451 		s16 chan;
452 		aligned_s64 timestamp;
453 	} scan;
454 	int chan, ret, res;
455 
456 	memset(&scan, 0, sizeof(scan));
457 
458 	mutex_lock(&data->lock);
459 	chan = find_first_bit(indio_dev->active_scan_mask,
460 			      iio_get_masklength(indio_dev));
461 	ret = ads1015_get_adc_result(data, chan, &res);
462 	if (ret < 0) {
463 		mutex_unlock(&data->lock);
464 		goto err;
465 	}
466 
467 	scan.chan = res;
468 	mutex_unlock(&data->lock);
469 
470 	iio_push_to_buffers_with_ts(indio_dev, &scan, sizeof(scan),
471 				    iio_get_time_ns(indio_dev));
472 
473 err:
474 	iio_trigger_notify_done(indio_dev->trig);
475 
476 	return IRQ_HANDLED;
477 }
478 
479 static int ads1015_set_scale(struct ads1015_data *data,
480 			     struct iio_chan_spec const *chan,
481 			     int scale, int uscale)
482 {
483 	int i;
484 	int fullscale = div_s64((scale * 1000000LL + uscale) <<
485 				(chan->scan_type.realbits - 1), 1000000);
486 
487 	for (i = 0; i < ARRAY_SIZE(ads1015_fullscale_range); i++) {
488 		if (ads1015_fullscale_range[i] == fullscale) {
489 			data->channel_data[chan->address].pga = i;
490 			return 0;
491 		}
492 	}
493 
494 	return -EINVAL;
495 }
496 
497 static int ads1015_set_data_rate(struct ads1015_data *data, int chan, int rate)
498 {
499 	int i;
500 
501 	for (i = 0; i < data->chip->data_rate_len; i++) {
502 		if (data->chip->data_rate[i] == rate) {
503 			data->channel_data[chan].data_rate = i;
504 			return 0;
505 		}
506 	}
507 
508 	return -EINVAL;
509 }
510 
511 static int ads1015_read_avail(struct iio_dev *indio_dev,
512 			      struct iio_chan_spec const *chan,
513 			      const int **vals, int *type, int *length,
514 			      long mask)
515 {
516 	struct ads1015_data *data = iio_priv(indio_dev);
517 
518 	if (chan->type != IIO_VOLTAGE)
519 		return -EINVAL;
520 
521 	switch (mask) {
522 	case IIO_CHAN_INFO_SCALE:
523 		*type = IIO_VAL_FRACTIONAL_LOG2;
524 		*vals =  data->chip->scale;
525 		*length = data->chip->scale_len;
526 		return IIO_AVAIL_LIST;
527 	case IIO_CHAN_INFO_SAMP_FREQ:
528 		*type = IIO_VAL_INT;
529 		*vals = data->chip->data_rate;
530 		*length = data->chip->data_rate_len;
531 		return IIO_AVAIL_LIST;
532 	default:
533 		return -EINVAL;
534 	}
535 }
536 
537 static int __ads1015_read_info_raw(struct ads1015_data *data,
538 				   struct iio_chan_spec const *chan, int *val)
539 {
540 	int ret;
541 
542 	if (ads1015_event_channel_enabled(data) &&
543 	    data->event_channel != chan->address)
544 		return -EBUSY;
545 
546 	ret = ads1015_set_power_state(data, true);
547 	if (ret < 0)
548 		return ret;
549 
550 	ret = ads1015_get_adc_result(data, chan->address, val);
551 	if (ret < 0) {
552 		ads1015_set_power_state(data, false);
553 		return ret;
554 	}
555 
556 	*val = sign_extend32(*val >> chan->scan_type.shift,
557 			     chan->scan_type.realbits - 1);
558 
559 	return ads1015_set_power_state(data, false);
560 }
561 
562 static int ads1015_read_raw(struct iio_dev *indio_dev,
563 			    struct iio_chan_spec const *chan, int *val,
564 			    int *val2, long mask)
565 {
566 	int ret, idx;
567 	struct ads1015_data *data = iio_priv(indio_dev);
568 
569 	guard(mutex)(&data->lock);
570 	switch (mask) {
571 	case IIO_CHAN_INFO_RAW:
572 		if (!iio_device_claim_direct(indio_dev))
573 			return -EBUSY;
574 		ret = __ads1015_read_info_raw(data, chan, val);
575 		iio_device_release_direct(indio_dev);
576 		if (ret)
577 			return ret;
578 
579 		return IIO_VAL_INT;
580 	case IIO_CHAN_INFO_SCALE:
581 		idx = data->channel_data[chan->address].pga;
582 		*val = ads1015_fullscale_range[idx];
583 		*val2 = chan->scan_type.realbits - 1;
584 		return IIO_VAL_FRACTIONAL_LOG2;
585 	case IIO_CHAN_INFO_SAMP_FREQ:
586 		idx = data->channel_data[chan->address].data_rate;
587 		*val = data->chip->data_rate[idx];
588 		return IIO_VAL_INT;
589 	default:
590 		return -EINVAL;
591 	}
592 }
593 
594 static int ads1015_write_raw(struct iio_dev *indio_dev,
595 			     struct iio_chan_spec const *chan, int val,
596 			     int val2, long mask)
597 {
598 	struct ads1015_data *data = iio_priv(indio_dev);
599 
600 	guard(mutex)(&data->lock);
601 	switch (mask) {
602 	case IIO_CHAN_INFO_SCALE:
603 		return ads1015_set_scale(data, chan, val, val2);
604 	case IIO_CHAN_INFO_SAMP_FREQ:
605 		return ads1015_set_data_rate(data, chan->address, val);
606 	default:
607 		return -EINVAL;
608 	}
609 }
610 
611 static int ads1015_read_event(struct iio_dev *indio_dev,
612 	const struct iio_chan_spec *chan, enum iio_event_type type,
613 	enum iio_event_direction dir, enum iio_event_info info, int *val,
614 	int *val2)
615 {
616 	struct ads1015_data *data = iio_priv(indio_dev);
617 	unsigned int comp_queue;
618 	int period;
619 	int dr;
620 
621 	guard(mutex)(&data->lock);
622 
623 	switch (info) {
624 	case IIO_EV_INFO_VALUE:
625 		*val = (dir == IIO_EV_DIR_RISING) ?
626 			data->thresh_data[chan->address].high_thresh :
627 			data->thresh_data[chan->address].low_thresh;
628 		return IIO_VAL_INT;
629 	case IIO_EV_INFO_PERIOD:
630 		dr = data->channel_data[chan->address].data_rate;
631 		comp_queue = data->thresh_data[chan->address].comp_queue;
632 		period = ads1015_comp_queue[comp_queue] *
633 			USEC_PER_SEC / data->chip->data_rate[dr];
634 
635 		*val = period / USEC_PER_SEC;
636 		*val2 = period % USEC_PER_SEC;
637 		return IIO_VAL_INT_PLUS_MICRO;
638 	default:
639 		return -EINVAL;
640 	}
641 }
642 
643 static int ads1015_write_event(struct iio_dev *indio_dev,
644 	const struct iio_chan_spec *chan, enum iio_event_type type,
645 	enum iio_event_direction dir, enum iio_event_info info, int val,
646 	int val2)
647 {
648 	struct ads1015_data *data = iio_priv(indio_dev);
649 	const int *data_rate = data->chip->data_rate;
650 	int realbits = chan->scan_type.realbits;
651 	long long period;
652 	int i;
653 	int dr;
654 
655 	guard(mutex)(&data->lock);
656 
657 	switch (info) {
658 	case IIO_EV_INFO_VALUE:
659 		if (val >= 1 << (realbits - 1) || val < -1 << (realbits - 1))
660 			return -EINVAL;
661 
662 		if (dir == IIO_EV_DIR_RISING)
663 			data->thresh_data[chan->address].high_thresh = val;
664 		else
665 			data->thresh_data[chan->address].low_thresh = val;
666 		return 0;
667 	case IIO_EV_INFO_PERIOD:
668 		dr = data->channel_data[chan->address].data_rate;
669 		period = val * USEC_PER_SEC + val2;
670 
671 		for (i = 0; i < ARRAY_SIZE(ads1015_comp_queue) - 1; i++) {
672 			if (period <= ads1015_comp_queue[i] *
673 					USEC_PER_SEC / data_rate[dr])
674 				break;
675 		}
676 		data->thresh_data[chan->address].comp_queue = i;
677 		return 0;
678 	default:
679 		return -EINVAL;
680 	}
681 }
682 
683 static int ads1015_read_event_config(struct iio_dev *indio_dev,
684 	const struct iio_chan_spec *chan, enum iio_event_type type,
685 	enum iio_event_direction dir)
686 {
687 	struct ads1015_data *data = iio_priv(indio_dev);
688 
689 	guard(mutex)(&data->lock);
690 	if (data->event_channel != chan->address)
691 		return 0;
692 
693 	switch (dir) {
694 	case IIO_EV_DIR_RISING:
695 		return 1;
696 	case IIO_EV_DIR_EITHER:
697 		return (data->comp_mode == ADS1015_CFG_COMP_MODE_WINDOW);
698 	default:
699 		return -EINVAL;
700 	}
701 }
702 
703 static int ads1015_enable_event_config(struct ads1015_data *data,
704 	const struct iio_chan_spec *chan, int comp_mode)
705 {
706 	int low_thresh = data->thresh_data[chan->address].low_thresh;
707 	int high_thresh = data->thresh_data[chan->address].high_thresh;
708 	int ret;
709 	unsigned int val;
710 
711 	if (ads1015_event_channel_enabled(data)) {
712 		if (data->event_channel != chan->address ||
713 			(data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD &&
714 				comp_mode == ADS1015_CFG_COMP_MODE_WINDOW))
715 			return -EBUSY;
716 
717 		return 0;
718 	}
719 
720 	if (comp_mode == ADS1015_CFG_COMP_MODE_TRAD) {
721 		low_thresh = max(-1 << (chan->scan_type.realbits - 1),
722 				high_thresh - 1);
723 	}
724 	ret = regmap_write(data->regmap, ADS1015_LO_THRESH_REG,
725 			low_thresh << chan->scan_type.shift);
726 	if (ret)
727 		return ret;
728 
729 	ret = regmap_write(data->regmap, ADS1015_HI_THRESH_REG,
730 			high_thresh << chan->scan_type.shift);
731 	if (ret)
732 		return ret;
733 
734 	ret = ads1015_set_power_state(data, true);
735 	if (ret < 0)
736 		return ret;
737 
738 	ads1015_event_channel_enable(data, chan->address, comp_mode);
739 
740 	ret = ads1015_get_adc_result(data, chan->address, &val);
741 	if (ret) {
742 		ads1015_event_channel_disable(data, chan->address);
743 		ads1015_set_power_state(data, false);
744 	}
745 
746 	return ret;
747 }
748 
749 static int ads1015_disable_event_config(struct ads1015_data *data,
750 	const struct iio_chan_spec *chan, int comp_mode)
751 {
752 	int ret;
753 
754 	if (!ads1015_event_channel_enabled(data))
755 		return 0;
756 
757 	if (data->event_channel != chan->address)
758 		return 0;
759 
760 	if (data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD &&
761 			comp_mode == ADS1015_CFG_COMP_MODE_WINDOW)
762 		return 0;
763 
764 	ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG,
765 				ADS1015_CFG_COMP_QUE_MASK,
766 				ADS1015_CFG_COMP_DISABLE <<
767 					ADS1015_CFG_COMP_QUE_SHIFT);
768 	if (ret)
769 		return ret;
770 
771 	ads1015_event_channel_disable(data, chan->address);
772 
773 	return ads1015_set_power_state(data, false);
774 }
775 
776 static int ads1015_write_event_config(struct iio_dev *indio_dev,
777 	const struct iio_chan_spec *chan, enum iio_event_type type,
778 	enum iio_event_direction dir, bool state)
779 {
780 	struct ads1015_data *data = iio_priv(indio_dev);
781 	int ret;
782 	int comp_mode = (dir == IIO_EV_DIR_EITHER) ?
783 		ADS1015_CFG_COMP_MODE_WINDOW : ADS1015_CFG_COMP_MODE_TRAD;
784 
785 	guard(mutex)(&data->lock);
786 
787 	/* Prevent from enabling both buffer and event at a time */
788 	if (!iio_device_claim_direct(indio_dev))
789 		return -EBUSY;
790 
791 	if (state)
792 		ret = ads1015_enable_event_config(data, chan, comp_mode);
793 	else
794 		ret = ads1015_disable_event_config(data, chan, comp_mode);
795 
796 	iio_device_release_direct(indio_dev);
797 	return ret;
798 }
799 
800 static irqreturn_t ads1015_event_handler(int irq, void *priv)
801 {
802 	struct iio_dev *indio_dev = priv;
803 	struct ads1015_data *data = iio_priv(indio_dev);
804 	int val;
805 	int ret;
806 
807 	/* Clear the latched ALERT/RDY pin */
808 	ret = regmap_read(data->regmap, ADS1015_CONV_REG, &val);
809 	if (ret)
810 		return IRQ_HANDLED;
811 
812 	if (ads1015_event_channel_enabled(data)) {
813 		enum iio_event_direction dir;
814 		u64 code;
815 
816 		dir = data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD ?
817 					IIO_EV_DIR_RISING : IIO_EV_DIR_EITHER;
818 		code = IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, data->event_channel,
819 					IIO_EV_TYPE_THRESH, dir);
820 		iio_push_event(indio_dev, code, iio_get_time_ns(indio_dev));
821 	}
822 
823 	return IRQ_HANDLED;
824 }
825 
826 static int ads1015_buffer_preenable(struct iio_dev *indio_dev)
827 {
828 	struct ads1015_data *data = iio_priv(indio_dev);
829 
830 	/* Prevent from enabling both buffer and event at a time */
831 	if (ads1015_event_channel_enabled(data))
832 		return -EBUSY;
833 
834 	return ads1015_set_power_state(iio_priv(indio_dev), true);
835 }
836 
837 static int ads1015_buffer_postdisable(struct iio_dev *indio_dev)
838 {
839 	return ads1015_set_power_state(iio_priv(indio_dev), false);
840 }
841 
842 static const struct iio_buffer_setup_ops ads1015_buffer_setup_ops = {
843 	.preenable	= ads1015_buffer_preenable,
844 	.postdisable	= ads1015_buffer_postdisable,
845 	.validate_scan_mask = &iio_validate_scan_mask_onehot,
846 };
847 
848 static const struct iio_info ads1015_info = {
849 	.read_avail	= ads1015_read_avail,
850 	.read_raw	= ads1015_read_raw,
851 	.write_raw	= ads1015_write_raw,
852 	.read_event_value = ads1015_read_event,
853 	.write_event_value = ads1015_write_event,
854 	.read_event_config = ads1015_read_event_config,
855 	.write_event_config = ads1015_write_event_config,
856 };
857 
858 static const struct iio_info tla2024_info = {
859 	.read_avail	= ads1015_read_avail,
860 	.read_raw	= ads1015_read_raw,
861 	.write_raw	= ads1015_write_raw,
862 };
863 
864 static int ads1015_client_get_channels_config(struct i2c_client *client)
865 {
866 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
867 	struct ads1015_data *data = iio_priv(indio_dev);
868 	struct device *dev = &client->dev;
869 	int i = -1;
870 
871 	device_for_each_child_node_scoped(dev, node) {
872 		u32 pval;
873 		unsigned int channel;
874 		unsigned int pga = ADS1015_DEFAULT_PGA;
875 		unsigned int data_rate = ADS1015_DEFAULT_DATA_RATE;
876 
877 		if (fwnode_property_read_u32(node, "reg", &pval)) {
878 			dev_err(dev, "invalid reg on %pfw\n", node);
879 			continue;
880 		}
881 
882 		channel = pval;
883 		if (channel >= ADS1015_CHANNELS) {
884 			dev_err(dev, "invalid channel index %d on %pfw\n",
885 				channel, node);
886 			continue;
887 		}
888 
889 		if (!fwnode_property_read_u32(node, "ti,gain", &pval)) {
890 			pga = pval;
891 			if (pga > 5) {
892 				dev_err(dev, "invalid gain on %pfw\n", node);
893 				return -EINVAL;
894 			}
895 		}
896 
897 		if (!fwnode_property_read_u32(node, "ti,datarate", &pval)) {
898 			data_rate = pval;
899 			if (data_rate > 7) {
900 				dev_err(dev, "invalid data_rate on %pfw\n", node);
901 				return -EINVAL;
902 			}
903 		}
904 
905 		data->channel_data[channel].pga = pga;
906 		data->channel_data[channel].data_rate = data_rate;
907 
908 		i++;
909 	}
910 
911 	return i < 0 ? -EINVAL : 0;
912 }
913 
914 static void ads1015_get_channels_config(struct i2c_client *client)
915 {
916 	unsigned int k;
917 
918 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
919 	struct ads1015_data *data = iio_priv(indio_dev);
920 
921 	if (!ads1015_client_get_channels_config(client))
922 		return;
923 
924 	/* fallback on default configuration */
925 	for (k = 0; k < ADS1015_CHANNELS; ++k) {
926 		data->channel_data[k].pga = ADS1015_DEFAULT_PGA;
927 		data->channel_data[k].data_rate = ADS1015_DEFAULT_DATA_RATE;
928 	}
929 }
930 
931 static int ads1015_set_conv_mode(struct ads1015_data *data, int mode)
932 {
933 	return regmap_update_bits(data->regmap, ADS1015_CFG_REG,
934 				  ADS1015_CFG_MOD_MASK,
935 				  mode << ADS1015_CFG_MOD_SHIFT);
936 }
937 
938 static int ads1015_probe(struct i2c_client *client)
939 {
940 	const struct ads1015_chip_data *chip;
941 	struct iio_dev *indio_dev;
942 	struct ads1015_data *data;
943 	int ret;
944 	int i;
945 
946 	chip = i2c_get_match_data(client);
947 	if (!chip)
948 		return dev_err_probe(&client->dev, -EINVAL, "Unknown chip\n");
949 
950 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
951 	if (!indio_dev)
952 		return -ENOMEM;
953 
954 	data = iio_priv(indio_dev);
955 	i2c_set_clientdata(client, indio_dev);
956 
957 	mutex_init(&data->lock);
958 
959 	indio_dev->name = ADS1015_DRV_NAME;
960 	indio_dev->modes = INDIO_DIRECT_MODE;
961 
962 	indio_dev->channels = chip->channels;
963 	indio_dev->num_channels = chip->num_channels;
964 	indio_dev->info = chip->info;
965 	data->chip = chip;
966 	data->event_channel = ADS1015_CHANNELS;
967 
968 	/*
969 	 * Set default lower and upper threshold to min and max value
970 	 * respectively.
971 	 */
972 	for (i = 0; i < ADS1015_CHANNELS; i++) {
973 		int realbits = indio_dev->channels[i].scan_type.realbits;
974 
975 		data->thresh_data[i].low_thresh = -1 << (realbits - 1);
976 		data->thresh_data[i].high_thresh = (1 << (realbits - 1)) - 1;
977 	}
978 
979 	/* we need to keep this ABI the same as used by hwmon ADS1015 driver */
980 	ads1015_get_channels_config(client);
981 
982 	data->regmap = devm_regmap_init_i2c(client, chip->has_comparator ?
983 					    &ads1015_regmap_config :
984 					    &tla2024_regmap_config);
985 	if (IS_ERR(data->regmap)) {
986 		dev_err(&client->dev, "Failed to allocate register map\n");
987 		return PTR_ERR(data->regmap);
988 	}
989 
990 	ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
991 					      ads1015_trigger_handler,
992 					      &ads1015_buffer_setup_ops);
993 	if (ret < 0) {
994 		dev_err(&client->dev, "iio triggered buffer setup failed\n");
995 		return ret;
996 	}
997 
998 	if (client->irq && chip->has_comparator) {
999 		unsigned long irq_trig = irq_get_trigger_type(client->irq);
1000 		unsigned int cfg_comp_mask = ADS1015_CFG_COMP_QUE_MASK |
1001 			ADS1015_CFG_COMP_LAT_MASK | ADS1015_CFG_COMP_POL_MASK;
1002 		unsigned int cfg_comp =
1003 			ADS1015_CFG_COMP_DISABLE << ADS1015_CFG_COMP_QUE_SHIFT |
1004 			1 << ADS1015_CFG_COMP_LAT_SHIFT;
1005 
1006 		switch (irq_trig) {
1007 		case IRQF_TRIGGER_FALLING:
1008 		case IRQF_TRIGGER_LOW:
1009 			cfg_comp |= ADS1015_CFG_COMP_POL_LOW <<
1010 					ADS1015_CFG_COMP_POL_SHIFT;
1011 			break;
1012 		case IRQF_TRIGGER_HIGH:
1013 		case IRQF_TRIGGER_RISING:
1014 			cfg_comp |= ADS1015_CFG_COMP_POL_HIGH <<
1015 					ADS1015_CFG_COMP_POL_SHIFT;
1016 			break;
1017 		default:
1018 			return -EINVAL;
1019 		}
1020 
1021 		ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG,
1022 					cfg_comp_mask, cfg_comp);
1023 		if (ret)
1024 			return ret;
1025 
1026 		ret = devm_request_threaded_irq(&client->dev, client->irq,
1027 						NULL, ads1015_event_handler,
1028 						irq_trig | IRQF_ONESHOT,
1029 						client->name, indio_dev);
1030 		if (ret)
1031 			return ret;
1032 	}
1033 
1034 	ret = ads1015_set_conv_mode(data, ADS1015_CONTINUOUS);
1035 	if (ret)
1036 		return ret;
1037 
1038 	data->conv_invalid = true;
1039 
1040 	ret = pm_runtime_set_active(&client->dev);
1041 	if (ret)
1042 		return ret;
1043 	pm_runtime_set_autosuspend_delay(&client->dev, ADS1015_SLEEP_DELAY_MS);
1044 	pm_runtime_use_autosuspend(&client->dev);
1045 	pm_runtime_enable(&client->dev);
1046 
1047 	ret = iio_device_register(indio_dev);
1048 	if (ret < 0) {
1049 		dev_err(&client->dev, "Failed to register IIO device\n");
1050 		return ret;
1051 	}
1052 
1053 	return 0;
1054 }
1055 
1056 static void ads1015_remove(struct i2c_client *client)
1057 {
1058 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
1059 	struct ads1015_data *data = iio_priv(indio_dev);
1060 	int ret;
1061 
1062 	iio_device_unregister(indio_dev);
1063 
1064 	pm_runtime_disable(&client->dev);
1065 	pm_runtime_set_suspended(&client->dev);
1066 
1067 	/* power down single shot mode */
1068 	ret = ads1015_set_conv_mode(data, ADS1015_SINGLESHOT);
1069 	if (ret)
1070 		dev_warn(&client->dev, "Failed to power down (%pe)\n",
1071 			 ERR_PTR(ret));
1072 }
1073 
1074 #ifdef CONFIG_PM
1075 static int ads1015_runtime_suspend(struct device *dev)
1076 {
1077 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1078 	struct ads1015_data *data = iio_priv(indio_dev);
1079 
1080 	return ads1015_set_conv_mode(data, ADS1015_SINGLESHOT);
1081 }
1082 
1083 static int ads1015_runtime_resume(struct device *dev)
1084 {
1085 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1086 	struct ads1015_data *data = iio_priv(indio_dev);
1087 	int ret;
1088 
1089 	ret = ads1015_set_conv_mode(data, ADS1015_CONTINUOUS);
1090 	if (!ret)
1091 		data->conv_invalid = true;
1092 
1093 	return ret;
1094 }
1095 #endif
1096 
1097 static const struct dev_pm_ops ads1015_pm_ops = {
1098 	SET_RUNTIME_PM_OPS(ads1015_runtime_suspend,
1099 			   ads1015_runtime_resume, NULL)
1100 };
1101 
1102 static const struct ads1015_chip_data ads1015_data = {
1103 	.channels	= ads1015_channels,
1104 	.num_channels	= ARRAY_SIZE(ads1015_channels),
1105 	.info		= &ads1015_info,
1106 	.data_rate	= ads1015_data_rate,
1107 	.data_rate_len	= ARRAY_SIZE(ads1015_data_rate),
1108 	.scale		= ads1015_scale,
1109 	.scale_len	= ARRAY_SIZE(ads1015_scale),
1110 	.has_comparator	= true,
1111 };
1112 
1113 static const struct ads1015_chip_data ads1115_data = {
1114 	.channels	= ads1115_channels,
1115 	.num_channels	= ARRAY_SIZE(ads1115_channels),
1116 	.info		= &ads1015_info,
1117 	.data_rate	= ads1115_data_rate,
1118 	.data_rate_len	= ARRAY_SIZE(ads1115_data_rate),
1119 	.scale		= ads1115_scale,
1120 	.scale_len	= ARRAY_SIZE(ads1115_scale),
1121 	.has_comparator	= true,
1122 };
1123 
1124 static const struct ads1015_chip_data tla2024_data = {
1125 	.channels	= tla2024_channels,
1126 	.num_channels	= ARRAY_SIZE(tla2024_channels),
1127 	.info		= &tla2024_info,
1128 	.data_rate	= ads1015_data_rate,
1129 	.data_rate_len	= ARRAY_SIZE(ads1015_data_rate),
1130 	.scale		= ads1015_scale,
1131 	.scale_len	= ARRAY_SIZE(ads1015_scale),
1132 	.has_comparator	= false,
1133 };
1134 
1135 static const struct i2c_device_id ads1015_id[] = {
1136 	{ "ads1015", (kernel_ulong_t)&ads1015_data },
1137 	{ "ads1115", (kernel_ulong_t)&ads1115_data },
1138 	{ "tla2024", (kernel_ulong_t)&tla2024_data },
1139 	{ }
1140 };
1141 MODULE_DEVICE_TABLE(i2c, ads1015_id);
1142 
1143 static const struct of_device_id ads1015_of_match[] = {
1144 	{ .compatible = "ti,ads1015", .data = &ads1015_data },
1145 	{ .compatible = "ti,ads1115", .data = &ads1115_data },
1146 	{ .compatible = "ti,tla2024", .data = &tla2024_data },
1147 	{ }
1148 };
1149 MODULE_DEVICE_TABLE(of, ads1015_of_match);
1150 
1151 static struct i2c_driver ads1015_driver = {
1152 	.driver = {
1153 		.name = ADS1015_DRV_NAME,
1154 		.of_match_table = ads1015_of_match,
1155 		.pm = &ads1015_pm_ops,
1156 	},
1157 	.probe		= ads1015_probe,
1158 	.remove		= ads1015_remove,
1159 	.id_table	= ads1015_id,
1160 };
1161 
1162 module_i2c_driver(ads1015_driver);
1163 
1164 MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
1165 MODULE_DESCRIPTION("Texas Instruments ADS1015 ADC driver");
1166 MODULE_LICENSE("GPL v2");
1167