xref: /linux/drivers/iio/adc/ti-ads1015.c (revision 68a052239fc4b351e961f698b824f7654a346091)
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 		ret = pm_runtime_put_autosuspend(dev);
381 
382 	return ret < 0 ? ret : 0;
383 }
384 
385 #else /* !CONFIG_PM */
386 
387 static int ads1015_set_power_state(struct ads1015_data *data, bool on)
388 {
389 	return 0;
390 }
391 
392 #endif /* !CONFIG_PM */
393 
394 static
395 int ads1015_get_adc_result(struct ads1015_data *data, int chan, int *val)
396 {
397 	const int *data_rate = data->chip->data_rate;
398 	int ret, pga, dr, dr_old, conv_time;
399 	unsigned int old, mask, cfg;
400 
401 	if (chan < 0 || chan >= ADS1015_CHANNELS)
402 		return -EINVAL;
403 
404 	ret = regmap_read(data->regmap, ADS1015_CFG_REG, &old);
405 	if (ret)
406 		return ret;
407 
408 	pga = data->channel_data[chan].pga;
409 	dr = data->channel_data[chan].data_rate;
410 	mask = ADS1015_CFG_MUX_MASK | ADS1015_CFG_PGA_MASK |
411 		ADS1015_CFG_DR_MASK;
412 	cfg = chan << ADS1015_CFG_MUX_SHIFT | pga << ADS1015_CFG_PGA_SHIFT |
413 		dr << ADS1015_CFG_DR_SHIFT;
414 
415 	if (ads1015_event_channel_enabled(data)) {
416 		mask |= ADS1015_CFG_COMP_QUE_MASK | ADS1015_CFG_COMP_MODE_MASK;
417 		cfg |= data->thresh_data[chan].comp_queue <<
418 				ADS1015_CFG_COMP_QUE_SHIFT |
419 			data->comp_mode <<
420 				ADS1015_CFG_COMP_MODE_SHIFT;
421 	}
422 
423 	cfg = (old & ~mask) | (cfg & mask);
424 	if (old != cfg) {
425 		ret = regmap_write(data->regmap, ADS1015_CFG_REG, cfg);
426 		if (ret)
427 			return ret;
428 		data->conv_invalid = true;
429 	}
430 	if (data->conv_invalid) {
431 		dr_old = (old & ADS1015_CFG_DR_MASK) >> ADS1015_CFG_DR_SHIFT;
432 		conv_time = DIV_ROUND_UP(USEC_PER_SEC, data_rate[dr_old]);
433 		conv_time += DIV_ROUND_UP(USEC_PER_SEC, data_rate[dr]);
434 		conv_time += conv_time / 10; /* 10% internal clock inaccuracy */
435 		usleep_range(conv_time, conv_time + 1);
436 		data->conv_invalid = false;
437 	}
438 
439 	return regmap_read(data->regmap, ADS1015_CONV_REG, val);
440 }
441 
442 static irqreturn_t ads1015_trigger_handler(int irq, void *p)
443 {
444 	struct iio_poll_func *pf = p;
445 	struct iio_dev *indio_dev = pf->indio_dev;
446 	struct ads1015_data *data = iio_priv(indio_dev);
447 	/* Ensure natural alignment of timestamp */
448 	struct {
449 		s16 chan;
450 		aligned_s64 timestamp;
451 	} scan = { };
452 	int chan, ret, res;
453 
454 	mutex_lock(&data->lock);
455 	chan = find_first_bit(indio_dev->active_scan_mask,
456 			      iio_get_masklength(indio_dev));
457 	ret = ads1015_get_adc_result(data, chan, &res);
458 	if (ret < 0) {
459 		mutex_unlock(&data->lock);
460 		goto err;
461 	}
462 
463 	scan.chan = res;
464 	mutex_unlock(&data->lock);
465 
466 	iio_push_to_buffers_with_ts(indio_dev, &scan, sizeof(scan),
467 				    iio_get_time_ns(indio_dev));
468 
469 err:
470 	iio_trigger_notify_done(indio_dev->trig);
471 
472 	return IRQ_HANDLED;
473 }
474 
475 static int ads1015_set_scale(struct ads1015_data *data,
476 			     struct iio_chan_spec const *chan,
477 			     int scale, int uscale)
478 {
479 	int i;
480 	int fullscale = div_s64((scale * 1000000LL + uscale) <<
481 				(chan->scan_type.realbits - 1), 1000000);
482 
483 	for (i = 0; i < ARRAY_SIZE(ads1015_fullscale_range); i++) {
484 		if (ads1015_fullscale_range[i] == fullscale) {
485 			data->channel_data[chan->address].pga = i;
486 			return 0;
487 		}
488 	}
489 
490 	return -EINVAL;
491 }
492 
493 static int ads1015_set_data_rate(struct ads1015_data *data, int chan, int rate)
494 {
495 	int i;
496 
497 	for (i = 0; i < data->chip->data_rate_len; i++) {
498 		if (data->chip->data_rate[i] == rate) {
499 			data->channel_data[chan].data_rate = i;
500 			return 0;
501 		}
502 	}
503 
504 	return -EINVAL;
505 }
506 
507 static int ads1015_read_avail(struct iio_dev *indio_dev,
508 			      struct iio_chan_spec const *chan,
509 			      const int **vals, int *type, int *length,
510 			      long mask)
511 {
512 	struct ads1015_data *data = iio_priv(indio_dev);
513 
514 	if (chan->type != IIO_VOLTAGE)
515 		return -EINVAL;
516 
517 	switch (mask) {
518 	case IIO_CHAN_INFO_SCALE:
519 		*type = IIO_VAL_FRACTIONAL_LOG2;
520 		*vals =  data->chip->scale;
521 		*length = data->chip->scale_len;
522 		return IIO_AVAIL_LIST;
523 	case IIO_CHAN_INFO_SAMP_FREQ:
524 		*type = IIO_VAL_INT;
525 		*vals = data->chip->data_rate;
526 		*length = data->chip->data_rate_len;
527 		return IIO_AVAIL_LIST;
528 	default:
529 		return -EINVAL;
530 	}
531 }
532 
533 static int __ads1015_read_info_raw(struct ads1015_data *data,
534 				   struct iio_chan_spec const *chan, int *val)
535 {
536 	int ret;
537 
538 	if (ads1015_event_channel_enabled(data) &&
539 	    data->event_channel != chan->address)
540 		return -EBUSY;
541 
542 	ret = ads1015_set_power_state(data, true);
543 	if (ret < 0)
544 		return ret;
545 
546 	ret = ads1015_get_adc_result(data, chan->address, val);
547 	if (ret < 0) {
548 		ads1015_set_power_state(data, false);
549 		return ret;
550 	}
551 
552 	*val = sign_extend32(*val >> chan->scan_type.shift,
553 			     chan->scan_type.realbits - 1);
554 
555 	return ads1015_set_power_state(data, false);
556 }
557 
558 static int ads1015_read_raw(struct iio_dev *indio_dev,
559 			    struct iio_chan_spec const *chan, int *val,
560 			    int *val2, long mask)
561 {
562 	int ret, idx;
563 	struct ads1015_data *data = iio_priv(indio_dev);
564 
565 	guard(mutex)(&data->lock);
566 	switch (mask) {
567 	case IIO_CHAN_INFO_RAW:
568 		if (!iio_device_claim_direct(indio_dev))
569 			return -EBUSY;
570 		ret = __ads1015_read_info_raw(data, chan, val);
571 		iio_device_release_direct(indio_dev);
572 		if (ret)
573 			return ret;
574 
575 		return IIO_VAL_INT;
576 	case IIO_CHAN_INFO_SCALE:
577 		idx = data->channel_data[chan->address].pga;
578 		*val = ads1015_fullscale_range[idx];
579 		*val2 = chan->scan_type.realbits - 1;
580 		return IIO_VAL_FRACTIONAL_LOG2;
581 	case IIO_CHAN_INFO_SAMP_FREQ:
582 		idx = data->channel_data[chan->address].data_rate;
583 		*val = data->chip->data_rate[idx];
584 		return IIO_VAL_INT;
585 	default:
586 		return -EINVAL;
587 	}
588 }
589 
590 static int ads1015_write_raw(struct iio_dev *indio_dev,
591 			     struct iio_chan_spec const *chan, int val,
592 			     int val2, long mask)
593 {
594 	struct ads1015_data *data = iio_priv(indio_dev);
595 
596 	guard(mutex)(&data->lock);
597 	switch (mask) {
598 	case IIO_CHAN_INFO_SCALE:
599 		return ads1015_set_scale(data, chan, val, val2);
600 	case IIO_CHAN_INFO_SAMP_FREQ:
601 		return ads1015_set_data_rate(data, chan->address, val);
602 	default:
603 		return -EINVAL;
604 	}
605 }
606 
607 static int ads1015_read_event(struct iio_dev *indio_dev,
608 	const struct iio_chan_spec *chan, enum iio_event_type type,
609 	enum iio_event_direction dir, enum iio_event_info info, int *val,
610 	int *val2)
611 {
612 	struct ads1015_data *data = iio_priv(indio_dev);
613 	unsigned int comp_queue;
614 	int period;
615 	int dr;
616 
617 	guard(mutex)(&data->lock);
618 
619 	switch (info) {
620 	case IIO_EV_INFO_VALUE:
621 		*val = (dir == IIO_EV_DIR_RISING) ?
622 			data->thresh_data[chan->address].high_thresh :
623 			data->thresh_data[chan->address].low_thresh;
624 		return IIO_VAL_INT;
625 	case IIO_EV_INFO_PERIOD:
626 		dr = data->channel_data[chan->address].data_rate;
627 		comp_queue = data->thresh_data[chan->address].comp_queue;
628 		period = ads1015_comp_queue[comp_queue] *
629 			USEC_PER_SEC / data->chip->data_rate[dr];
630 
631 		*val = period / USEC_PER_SEC;
632 		*val2 = period % USEC_PER_SEC;
633 		return IIO_VAL_INT_PLUS_MICRO;
634 	default:
635 		return -EINVAL;
636 	}
637 }
638 
639 static int ads1015_write_event(struct iio_dev *indio_dev,
640 	const struct iio_chan_spec *chan, enum iio_event_type type,
641 	enum iio_event_direction dir, enum iio_event_info info, int val,
642 	int val2)
643 {
644 	struct ads1015_data *data = iio_priv(indio_dev);
645 	const int *data_rate = data->chip->data_rate;
646 	int realbits = chan->scan_type.realbits;
647 	long long period;
648 	int i;
649 	int dr;
650 
651 	guard(mutex)(&data->lock);
652 
653 	switch (info) {
654 	case IIO_EV_INFO_VALUE:
655 		if (val >= 1 << (realbits - 1) || val < -1 << (realbits - 1))
656 			return -EINVAL;
657 
658 		if (dir == IIO_EV_DIR_RISING)
659 			data->thresh_data[chan->address].high_thresh = val;
660 		else
661 			data->thresh_data[chan->address].low_thresh = val;
662 		return 0;
663 	case IIO_EV_INFO_PERIOD:
664 		dr = data->channel_data[chan->address].data_rate;
665 		period = val * USEC_PER_SEC + val2;
666 
667 		for (i = 0; i < ARRAY_SIZE(ads1015_comp_queue) - 1; i++) {
668 			if (period <= ads1015_comp_queue[i] *
669 					USEC_PER_SEC / data_rate[dr])
670 				break;
671 		}
672 		data->thresh_data[chan->address].comp_queue = i;
673 		return 0;
674 	default:
675 		return -EINVAL;
676 	}
677 }
678 
679 static int ads1015_read_event_config(struct iio_dev *indio_dev,
680 	const struct iio_chan_spec *chan, enum iio_event_type type,
681 	enum iio_event_direction dir)
682 {
683 	struct ads1015_data *data = iio_priv(indio_dev);
684 
685 	guard(mutex)(&data->lock);
686 	if (data->event_channel != chan->address)
687 		return 0;
688 
689 	switch (dir) {
690 	case IIO_EV_DIR_RISING:
691 		return 1;
692 	case IIO_EV_DIR_EITHER:
693 		return (data->comp_mode == ADS1015_CFG_COMP_MODE_WINDOW);
694 	default:
695 		return -EINVAL;
696 	}
697 }
698 
699 static int ads1015_enable_event_config(struct ads1015_data *data,
700 	const struct iio_chan_spec *chan, int comp_mode)
701 {
702 	int low_thresh = data->thresh_data[chan->address].low_thresh;
703 	int high_thresh = data->thresh_data[chan->address].high_thresh;
704 	int ret;
705 	unsigned int val;
706 
707 	if (ads1015_event_channel_enabled(data)) {
708 		if (data->event_channel != chan->address ||
709 			(data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD &&
710 				comp_mode == ADS1015_CFG_COMP_MODE_WINDOW))
711 			return -EBUSY;
712 
713 		return 0;
714 	}
715 
716 	if (comp_mode == ADS1015_CFG_COMP_MODE_TRAD) {
717 		low_thresh = max(-1 << (chan->scan_type.realbits - 1),
718 				high_thresh - 1);
719 	}
720 	ret = regmap_write(data->regmap, ADS1015_LO_THRESH_REG,
721 			low_thresh << chan->scan_type.shift);
722 	if (ret)
723 		return ret;
724 
725 	ret = regmap_write(data->regmap, ADS1015_HI_THRESH_REG,
726 			high_thresh << chan->scan_type.shift);
727 	if (ret)
728 		return ret;
729 
730 	ret = ads1015_set_power_state(data, true);
731 	if (ret < 0)
732 		return ret;
733 
734 	ads1015_event_channel_enable(data, chan->address, comp_mode);
735 
736 	ret = ads1015_get_adc_result(data, chan->address, &val);
737 	if (ret) {
738 		ads1015_event_channel_disable(data, chan->address);
739 		ads1015_set_power_state(data, false);
740 	}
741 
742 	return ret;
743 }
744 
745 static int ads1015_disable_event_config(struct ads1015_data *data,
746 	const struct iio_chan_spec *chan, int comp_mode)
747 {
748 	int ret;
749 
750 	if (!ads1015_event_channel_enabled(data))
751 		return 0;
752 
753 	if (data->event_channel != chan->address)
754 		return 0;
755 
756 	if (data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD &&
757 			comp_mode == ADS1015_CFG_COMP_MODE_WINDOW)
758 		return 0;
759 
760 	ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG,
761 				ADS1015_CFG_COMP_QUE_MASK,
762 				ADS1015_CFG_COMP_DISABLE <<
763 					ADS1015_CFG_COMP_QUE_SHIFT);
764 	if (ret)
765 		return ret;
766 
767 	ads1015_event_channel_disable(data, chan->address);
768 
769 	return ads1015_set_power_state(data, false);
770 }
771 
772 static int ads1015_write_event_config(struct iio_dev *indio_dev,
773 	const struct iio_chan_spec *chan, enum iio_event_type type,
774 	enum iio_event_direction dir, bool state)
775 {
776 	struct ads1015_data *data = iio_priv(indio_dev);
777 	int ret;
778 	int comp_mode = (dir == IIO_EV_DIR_EITHER) ?
779 		ADS1015_CFG_COMP_MODE_WINDOW : ADS1015_CFG_COMP_MODE_TRAD;
780 
781 	guard(mutex)(&data->lock);
782 
783 	/* Prevent from enabling both buffer and event at a time */
784 	if (!iio_device_claim_direct(indio_dev))
785 		return -EBUSY;
786 
787 	if (state)
788 		ret = ads1015_enable_event_config(data, chan, comp_mode);
789 	else
790 		ret = ads1015_disable_event_config(data, chan, comp_mode);
791 
792 	iio_device_release_direct(indio_dev);
793 	return ret;
794 }
795 
796 static irqreturn_t ads1015_event_handler(int irq, void *priv)
797 {
798 	struct iio_dev *indio_dev = priv;
799 	struct ads1015_data *data = iio_priv(indio_dev);
800 	int val;
801 	int ret;
802 
803 	/* Clear the latched ALERT/RDY pin */
804 	ret = regmap_read(data->regmap, ADS1015_CONV_REG, &val);
805 	if (ret)
806 		return IRQ_HANDLED;
807 
808 	if (ads1015_event_channel_enabled(data)) {
809 		enum iio_event_direction dir;
810 		u64 code;
811 
812 		dir = data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD ?
813 					IIO_EV_DIR_RISING : IIO_EV_DIR_EITHER;
814 		code = IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, data->event_channel,
815 					IIO_EV_TYPE_THRESH, dir);
816 		iio_push_event(indio_dev, code, iio_get_time_ns(indio_dev));
817 	}
818 
819 	return IRQ_HANDLED;
820 }
821 
822 static int ads1015_buffer_preenable(struct iio_dev *indio_dev)
823 {
824 	struct ads1015_data *data = iio_priv(indio_dev);
825 
826 	/* Prevent from enabling both buffer and event at a time */
827 	if (ads1015_event_channel_enabled(data))
828 		return -EBUSY;
829 
830 	return ads1015_set_power_state(iio_priv(indio_dev), true);
831 }
832 
833 static int ads1015_buffer_postdisable(struct iio_dev *indio_dev)
834 {
835 	return ads1015_set_power_state(iio_priv(indio_dev), false);
836 }
837 
838 static const struct iio_buffer_setup_ops ads1015_buffer_setup_ops = {
839 	.preenable	= ads1015_buffer_preenable,
840 	.postdisable	= ads1015_buffer_postdisable,
841 	.validate_scan_mask = &iio_validate_scan_mask_onehot,
842 };
843 
844 static const struct iio_info ads1015_info = {
845 	.read_avail	= ads1015_read_avail,
846 	.read_raw	= ads1015_read_raw,
847 	.write_raw	= ads1015_write_raw,
848 	.read_event_value = ads1015_read_event,
849 	.write_event_value = ads1015_write_event,
850 	.read_event_config = ads1015_read_event_config,
851 	.write_event_config = ads1015_write_event_config,
852 };
853 
854 static const struct iio_info tla2024_info = {
855 	.read_avail	= ads1015_read_avail,
856 	.read_raw	= ads1015_read_raw,
857 	.write_raw	= ads1015_write_raw,
858 };
859 
860 static int ads1015_client_get_channels_config(struct i2c_client *client)
861 {
862 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
863 	struct ads1015_data *data = iio_priv(indio_dev);
864 	struct device *dev = &client->dev;
865 	int i = -1;
866 
867 	device_for_each_child_node_scoped(dev, node) {
868 		u32 pval;
869 		unsigned int channel;
870 		unsigned int pga = ADS1015_DEFAULT_PGA;
871 		unsigned int data_rate = ADS1015_DEFAULT_DATA_RATE;
872 
873 		if (fwnode_property_read_u32(node, "reg", &pval)) {
874 			dev_err(dev, "invalid reg on %pfw\n", node);
875 			continue;
876 		}
877 
878 		channel = pval;
879 		if (channel >= ADS1015_CHANNELS) {
880 			dev_err(dev, "invalid channel index %d on %pfw\n",
881 				channel, node);
882 			continue;
883 		}
884 
885 		if (!fwnode_property_read_u32(node, "ti,gain", &pval)) {
886 			pga = pval;
887 			if (pga > 5) {
888 				dev_err(dev, "invalid gain on %pfw\n", node);
889 				return -EINVAL;
890 			}
891 		}
892 
893 		if (!fwnode_property_read_u32(node, "ti,datarate", &pval)) {
894 			data_rate = pval;
895 			if (data_rate > 7) {
896 				dev_err(dev, "invalid data_rate on %pfw\n", node);
897 				return -EINVAL;
898 			}
899 		}
900 
901 		data->channel_data[channel].pga = pga;
902 		data->channel_data[channel].data_rate = data_rate;
903 
904 		i++;
905 	}
906 
907 	return i < 0 ? -EINVAL : 0;
908 }
909 
910 static void ads1015_get_channels_config(struct i2c_client *client)
911 {
912 	unsigned int k;
913 
914 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
915 	struct ads1015_data *data = iio_priv(indio_dev);
916 
917 	if (!ads1015_client_get_channels_config(client))
918 		return;
919 
920 	/* fallback on default configuration */
921 	for (k = 0; k < ADS1015_CHANNELS; ++k) {
922 		data->channel_data[k].pga = ADS1015_DEFAULT_PGA;
923 		data->channel_data[k].data_rate = ADS1015_DEFAULT_DATA_RATE;
924 	}
925 }
926 
927 static int ads1015_set_conv_mode(struct ads1015_data *data, int mode)
928 {
929 	return regmap_update_bits(data->regmap, ADS1015_CFG_REG,
930 				  ADS1015_CFG_MOD_MASK,
931 				  mode << ADS1015_CFG_MOD_SHIFT);
932 }
933 
934 static int ads1015_probe(struct i2c_client *client)
935 {
936 	const struct ads1015_chip_data *chip;
937 	struct iio_dev *indio_dev;
938 	struct ads1015_data *data;
939 	int ret;
940 	int i;
941 
942 	chip = i2c_get_match_data(client);
943 	if (!chip)
944 		return dev_err_probe(&client->dev, -EINVAL, "Unknown chip\n");
945 
946 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
947 	if (!indio_dev)
948 		return -ENOMEM;
949 
950 	data = iio_priv(indio_dev);
951 	i2c_set_clientdata(client, indio_dev);
952 
953 	mutex_init(&data->lock);
954 
955 	indio_dev->name = ADS1015_DRV_NAME;
956 	indio_dev->modes = INDIO_DIRECT_MODE;
957 
958 	indio_dev->channels = chip->channels;
959 	indio_dev->num_channels = chip->num_channels;
960 	indio_dev->info = chip->info;
961 	data->chip = chip;
962 	data->event_channel = ADS1015_CHANNELS;
963 
964 	/*
965 	 * Set default lower and upper threshold to min and max value
966 	 * respectively.
967 	 */
968 	for (i = 0; i < ADS1015_CHANNELS; i++) {
969 		int realbits = indio_dev->channels[i].scan_type.realbits;
970 
971 		data->thresh_data[i].low_thresh = -1 << (realbits - 1);
972 		data->thresh_data[i].high_thresh = (1 << (realbits - 1)) - 1;
973 	}
974 
975 	/* we need to keep this ABI the same as used by hwmon ADS1015 driver */
976 	ads1015_get_channels_config(client);
977 
978 	data->regmap = devm_regmap_init_i2c(client, chip->has_comparator ?
979 					    &ads1015_regmap_config :
980 					    &tla2024_regmap_config);
981 	if (IS_ERR(data->regmap)) {
982 		dev_err(&client->dev, "Failed to allocate register map\n");
983 		return PTR_ERR(data->regmap);
984 	}
985 
986 	ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
987 					      ads1015_trigger_handler,
988 					      &ads1015_buffer_setup_ops);
989 	if (ret < 0) {
990 		dev_err(&client->dev, "iio triggered buffer setup failed\n");
991 		return ret;
992 	}
993 
994 	if (client->irq && chip->has_comparator) {
995 		unsigned long irq_trig = irq_get_trigger_type(client->irq);
996 		unsigned int cfg_comp_mask = ADS1015_CFG_COMP_QUE_MASK |
997 			ADS1015_CFG_COMP_LAT_MASK | ADS1015_CFG_COMP_POL_MASK;
998 		unsigned int cfg_comp =
999 			ADS1015_CFG_COMP_DISABLE << ADS1015_CFG_COMP_QUE_SHIFT |
1000 			1 << ADS1015_CFG_COMP_LAT_SHIFT;
1001 
1002 		switch (irq_trig) {
1003 		case IRQF_TRIGGER_FALLING:
1004 		case IRQF_TRIGGER_LOW:
1005 			cfg_comp |= ADS1015_CFG_COMP_POL_LOW <<
1006 					ADS1015_CFG_COMP_POL_SHIFT;
1007 			break;
1008 		case IRQF_TRIGGER_HIGH:
1009 		case IRQF_TRIGGER_RISING:
1010 			cfg_comp |= ADS1015_CFG_COMP_POL_HIGH <<
1011 					ADS1015_CFG_COMP_POL_SHIFT;
1012 			break;
1013 		default:
1014 			return -EINVAL;
1015 		}
1016 
1017 		ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG,
1018 					cfg_comp_mask, cfg_comp);
1019 		if (ret)
1020 			return ret;
1021 
1022 		ret = devm_request_threaded_irq(&client->dev, client->irq,
1023 						NULL, ads1015_event_handler,
1024 						irq_trig | IRQF_ONESHOT,
1025 						client->name, indio_dev);
1026 		if (ret)
1027 			return ret;
1028 	}
1029 
1030 	ret = ads1015_set_conv_mode(data, ADS1015_CONTINUOUS);
1031 	if (ret)
1032 		return ret;
1033 
1034 	data->conv_invalid = true;
1035 
1036 	ret = pm_runtime_set_active(&client->dev);
1037 	if (ret)
1038 		return ret;
1039 	pm_runtime_set_autosuspend_delay(&client->dev, ADS1015_SLEEP_DELAY_MS);
1040 	pm_runtime_use_autosuspend(&client->dev);
1041 	pm_runtime_enable(&client->dev);
1042 
1043 	ret = iio_device_register(indio_dev);
1044 	if (ret < 0) {
1045 		dev_err(&client->dev, "Failed to register IIO device\n");
1046 		return ret;
1047 	}
1048 
1049 	return 0;
1050 }
1051 
1052 static void ads1015_remove(struct i2c_client *client)
1053 {
1054 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
1055 	struct ads1015_data *data = iio_priv(indio_dev);
1056 	int ret;
1057 
1058 	iio_device_unregister(indio_dev);
1059 
1060 	pm_runtime_disable(&client->dev);
1061 	pm_runtime_set_suspended(&client->dev);
1062 
1063 	/* power down single shot mode */
1064 	ret = ads1015_set_conv_mode(data, ADS1015_SINGLESHOT);
1065 	if (ret)
1066 		dev_warn(&client->dev, "Failed to power down (%pe)\n",
1067 			 ERR_PTR(ret));
1068 }
1069 
1070 #ifdef CONFIG_PM
1071 static int ads1015_runtime_suspend(struct device *dev)
1072 {
1073 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1074 	struct ads1015_data *data = iio_priv(indio_dev);
1075 
1076 	return ads1015_set_conv_mode(data, ADS1015_SINGLESHOT);
1077 }
1078 
1079 static int ads1015_runtime_resume(struct device *dev)
1080 {
1081 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1082 	struct ads1015_data *data = iio_priv(indio_dev);
1083 	int ret;
1084 
1085 	ret = ads1015_set_conv_mode(data, ADS1015_CONTINUOUS);
1086 	if (!ret)
1087 		data->conv_invalid = true;
1088 
1089 	return ret;
1090 }
1091 #endif
1092 
1093 static const struct dev_pm_ops ads1015_pm_ops = {
1094 	SET_RUNTIME_PM_OPS(ads1015_runtime_suspend,
1095 			   ads1015_runtime_resume, NULL)
1096 };
1097 
1098 static const struct ads1015_chip_data ads1015_data = {
1099 	.channels	= ads1015_channels,
1100 	.num_channels	= ARRAY_SIZE(ads1015_channels),
1101 	.info		= &ads1015_info,
1102 	.data_rate	= ads1015_data_rate,
1103 	.data_rate_len	= ARRAY_SIZE(ads1015_data_rate),
1104 	.scale		= ads1015_scale,
1105 	.scale_len	= ARRAY_SIZE(ads1015_scale),
1106 	.has_comparator	= true,
1107 };
1108 
1109 static const struct ads1015_chip_data ads1115_data = {
1110 	.channels	= ads1115_channels,
1111 	.num_channels	= ARRAY_SIZE(ads1115_channels),
1112 	.info		= &ads1015_info,
1113 	.data_rate	= ads1115_data_rate,
1114 	.data_rate_len	= ARRAY_SIZE(ads1115_data_rate),
1115 	.scale		= ads1115_scale,
1116 	.scale_len	= ARRAY_SIZE(ads1115_scale),
1117 	.has_comparator	= true,
1118 };
1119 
1120 static const struct ads1015_chip_data tla2024_data = {
1121 	.channels	= tla2024_channels,
1122 	.num_channels	= ARRAY_SIZE(tla2024_channels),
1123 	.info		= &tla2024_info,
1124 	.data_rate	= ads1015_data_rate,
1125 	.data_rate_len	= ARRAY_SIZE(ads1015_data_rate),
1126 	.scale		= ads1015_scale,
1127 	.scale_len	= ARRAY_SIZE(ads1015_scale),
1128 	.has_comparator	= false,
1129 };
1130 
1131 static const struct i2c_device_id ads1015_id[] = {
1132 	{ "ads1015", (kernel_ulong_t)&ads1015_data },
1133 	{ "ads1115", (kernel_ulong_t)&ads1115_data },
1134 	{ "tla2024", (kernel_ulong_t)&tla2024_data },
1135 	{ }
1136 };
1137 MODULE_DEVICE_TABLE(i2c, ads1015_id);
1138 
1139 static const struct of_device_id ads1015_of_match[] = {
1140 	{ .compatible = "ti,ads1015", .data = &ads1015_data },
1141 	{ .compatible = "ti,ads1115", .data = &ads1115_data },
1142 	{ .compatible = "ti,tla2024", .data = &tla2024_data },
1143 	{ }
1144 };
1145 MODULE_DEVICE_TABLE(of, ads1015_of_match);
1146 
1147 static struct i2c_driver ads1015_driver = {
1148 	.driver = {
1149 		.name = ADS1015_DRV_NAME,
1150 		.of_match_table = ads1015_of_match,
1151 		.pm = &ads1015_pm_ops,
1152 	},
1153 	.probe		= ads1015_probe,
1154 	.remove		= ads1015_remove,
1155 	.id_table	= ads1015_id,
1156 };
1157 
1158 module_i2c_driver(ads1015_driver);
1159 
1160 MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
1161 MODULE_DESCRIPTION("Texas Instruments ADS1015 ADC driver");
1162 MODULE_LICENSE("GPL v2");
1163