xref: /openbmc/linux/drivers/iio/adc/ti-ads1015.c (revision dc6a81c3)
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/init.h>
16 #include <linux/irq.h>
17 #include <linux/i2c.h>
18 #include <linux/property.h>
19 #include <linux/regmap.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/mutex.h>
22 #include <linux/delay.h>
23 
24 #include <linux/iio/iio.h>
25 #include <linux/iio/types.h>
26 #include <linux/iio/sysfs.h>
27 #include <linux/iio/events.h>
28 #include <linux/iio/buffer.h>
29 #include <linux/iio/triggered_buffer.h>
30 #include <linux/iio/trigger_consumer.h>
31 
32 #define ADS1015_DRV_NAME "ads1015"
33 
34 #define ADS1015_CHANNELS 8
35 
36 #define ADS1015_CONV_REG	0x00
37 #define ADS1015_CFG_REG		0x01
38 #define ADS1015_LO_THRESH_REG	0x02
39 #define ADS1015_HI_THRESH_REG	0x03
40 
41 #define ADS1015_CFG_COMP_QUE_SHIFT	0
42 #define ADS1015_CFG_COMP_LAT_SHIFT	2
43 #define ADS1015_CFG_COMP_POL_SHIFT	3
44 #define ADS1015_CFG_COMP_MODE_SHIFT	4
45 #define ADS1015_CFG_DR_SHIFT	5
46 #define ADS1015_CFG_MOD_SHIFT	8
47 #define ADS1015_CFG_PGA_SHIFT	9
48 #define ADS1015_CFG_MUX_SHIFT	12
49 
50 #define ADS1015_CFG_COMP_QUE_MASK	GENMASK(1, 0)
51 #define ADS1015_CFG_COMP_LAT_MASK	BIT(2)
52 #define ADS1015_CFG_COMP_POL_MASK	BIT(3)
53 #define ADS1015_CFG_COMP_MODE_MASK	BIT(4)
54 #define ADS1015_CFG_DR_MASK	GENMASK(7, 5)
55 #define ADS1015_CFG_MOD_MASK	BIT(8)
56 #define ADS1015_CFG_PGA_MASK	GENMASK(11, 9)
57 #define ADS1015_CFG_MUX_MASK	GENMASK(14, 12)
58 
59 /* Comparator queue and disable field */
60 #define ADS1015_CFG_COMP_DISABLE	3
61 
62 /* Comparator polarity field */
63 #define ADS1015_CFG_COMP_POL_LOW	0
64 #define ADS1015_CFG_COMP_POL_HIGH	1
65 
66 /* Comparator mode field */
67 #define ADS1015_CFG_COMP_MODE_TRAD	0
68 #define ADS1015_CFG_COMP_MODE_WINDOW	1
69 
70 /* device operating modes */
71 #define ADS1015_CONTINUOUS	0
72 #define ADS1015_SINGLESHOT	1
73 
74 #define ADS1015_SLEEP_DELAY_MS		2000
75 #define ADS1015_DEFAULT_PGA		2
76 #define ADS1015_DEFAULT_DATA_RATE	4
77 #define ADS1015_DEFAULT_CHAN		0
78 
79 enum chip_ids {
80 	ADSXXXX = 0,
81 	ADS1015,
82 	ADS1115,
83 };
84 
85 enum ads1015_channels {
86 	ADS1015_AIN0_AIN1 = 0,
87 	ADS1015_AIN0_AIN3,
88 	ADS1015_AIN1_AIN3,
89 	ADS1015_AIN2_AIN3,
90 	ADS1015_AIN0,
91 	ADS1015_AIN1,
92 	ADS1015_AIN2,
93 	ADS1015_AIN3,
94 	ADS1015_TIMESTAMP,
95 };
96 
97 static const unsigned int ads1015_data_rate[] = {
98 	128, 250, 490, 920, 1600, 2400, 3300, 3300
99 };
100 
101 static const unsigned int ads1115_data_rate[] = {
102 	8, 16, 32, 64, 128, 250, 475, 860
103 };
104 
105 /*
106  * Translation from PGA bits to full-scale positive and negative input voltage
107  * range in mV
108  */
109 static int ads1015_fullscale_range[] = {
110 	6144, 4096, 2048, 1024, 512, 256, 256, 256
111 };
112 
113 /*
114  * Translation from COMP_QUE field value to the number of successive readings
115  * exceed the threshold values before an interrupt is generated
116  */
117 static const int ads1015_comp_queue[] = { 1, 2, 4 };
118 
119 static const struct iio_event_spec ads1015_events[] = {
120 	{
121 		.type = IIO_EV_TYPE_THRESH,
122 		.dir = IIO_EV_DIR_RISING,
123 		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
124 				BIT(IIO_EV_INFO_ENABLE),
125 	}, {
126 		.type = IIO_EV_TYPE_THRESH,
127 		.dir = IIO_EV_DIR_FALLING,
128 		.mask_separate = BIT(IIO_EV_INFO_VALUE),
129 	}, {
130 		.type = IIO_EV_TYPE_THRESH,
131 		.dir = IIO_EV_DIR_EITHER,
132 		.mask_separate = BIT(IIO_EV_INFO_ENABLE) |
133 				BIT(IIO_EV_INFO_PERIOD),
134 	},
135 };
136 
137 #define ADS1015_V_CHAN(_chan, _addr) {				\
138 	.type = IIO_VOLTAGE,					\
139 	.indexed = 1,						\
140 	.address = _addr,					\
141 	.channel = _chan,					\
142 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
143 				BIT(IIO_CHAN_INFO_SCALE) |	\
144 				BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
145 	.scan_index = _addr,					\
146 	.scan_type = {						\
147 		.sign = 's',					\
148 		.realbits = 12,					\
149 		.storagebits = 16,				\
150 		.shift = 4,					\
151 		.endianness = IIO_CPU,				\
152 	},							\
153 	.event_spec = ads1015_events,				\
154 	.num_event_specs = ARRAY_SIZE(ads1015_events),		\
155 	.datasheet_name = "AIN"#_chan,				\
156 }
157 
158 #define ADS1015_V_DIFF_CHAN(_chan, _chan2, _addr) {		\
159 	.type = IIO_VOLTAGE,					\
160 	.differential = 1,					\
161 	.indexed = 1,						\
162 	.address = _addr,					\
163 	.channel = _chan,					\
164 	.channel2 = _chan2,					\
165 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
166 				BIT(IIO_CHAN_INFO_SCALE) |	\
167 				BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
168 	.scan_index = _addr,					\
169 	.scan_type = {						\
170 		.sign = 's',					\
171 		.realbits = 12,					\
172 		.storagebits = 16,				\
173 		.shift = 4,					\
174 		.endianness = IIO_CPU,				\
175 	},							\
176 	.event_spec = ads1015_events,				\
177 	.num_event_specs = ARRAY_SIZE(ads1015_events),		\
178 	.datasheet_name = "AIN"#_chan"-AIN"#_chan2,		\
179 }
180 
181 #define ADS1115_V_CHAN(_chan, _addr) {				\
182 	.type = IIO_VOLTAGE,					\
183 	.indexed = 1,						\
184 	.address = _addr,					\
185 	.channel = _chan,					\
186 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
187 				BIT(IIO_CHAN_INFO_SCALE) |	\
188 				BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
189 	.scan_index = _addr,					\
190 	.scan_type = {						\
191 		.sign = 's',					\
192 		.realbits = 16,					\
193 		.storagebits = 16,				\
194 		.endianness = IIO_CPU,				\
195 	},							\
196 	.event_spec = ads1015_events,				\
197 	.num_event_specs = ARRAY_SIZE(ads1015_events),		\
198 	.datasheet_name = "AIN"#_chan,				\
199 }
200 
201 #define ADS1115_V_DIFF_CHAN(_chan, _chan2, _addr) {		\
202 	.type = IIO_VOLTAGE,					\
203 	.differential = 1,					\
204 	.indexed = 1,						\
205 	.address = _addr,					\
206 	.channel = _chan,					\
207 	.channel2 = _chan2,					\
208 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
209 				BIT(IIO_CHAN_INFO_SCALE) |	\
210 				BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
211 	.scan_index = _addr,					\
212 	.scan_type = {						\
213 		.sign = 's',					\
214 		.realbits = 16,					\
215 		.storagebits = 16,				\
216 		.endianness = IIO_CPU,				\
217 	},							\
218 	.event_spec = ads1015_events,				\
219 	.num_event_specs = ARRAY_SIZE(ads1015_events),		\
220 	.datasheet_name = "AIN"#_chan"-AIN"#_chan2,		\
221 }
222 
223 struct ads1015_channel_data {
224 	bool enabled;
225 	unsigned int pga;
226 	unsigned int data_rate;
227 };
228 
229 struct ads1015_thresh_data {
230 	unsigned int comp_queue;
231 	int high_thresh;
232 	int low_thresh;
233 };
234 
235 struct ads1015_data {
236 	struct regmap *regmap;
237 	/*
238 	 * Protects ADC ops, e.g: concurrent sysfs/buffered
239 	 * data reads, configuration updates
240 	 */
241 	struct mutex lock;
242 	struct ads1015_channel_data channel_data[ADS1015_CHANNELS];
243 
244 	unsigned int event_channel;
245 	unsigned int comp_mode;
246 	struct ads1015_thresh_data thresh_data[ADS1015_CHANNELS];
247 
248 	unsigned int *data_rate;
249 	/*
250 	 * Set to true when the ADC is switched to the continuous-conversion
251 	 * mode and exits from a power-down state.  This flag is used to avoid
252 	 * getting the stale result from the conversion register.
253 	 */
254 	bool conv_invalid;
255 };
256 
257 static bool ads1015_event_channel_enabled(struct ads1015_data *data)
258 {
259 	return (data->event_channel != ADS1015_CHANNELS);
260 }
261 
262 static void ads1015_event_channel_enable(struct ads1015_data *data, int chan,
263 					 int comp_mode)
264 {
265 	WARN_ON(ads1015_event_channel_enabled(data));
266 
267 	data->event_channel = chan;
268 	data->comp_mode = comp_mode;
269 }
270 
271 static void ads1015_event_channel_disable(struct ads1015_data *data, int chan)
272 {
273 	data->event_channel = ADS1015_CHANNELS;
274 }
275 
276 static bool ads1015_is_writeable_reg(struct device *dev, unsigned int reg)
277 {
278 	switch (reg) {
279 	case ADS1015_CFG_REG:
280 	case ADS1015_LO_THRESH_REG:
281 	case ADS1015_HI_THRESH_REG:
282 		return true;
283 	default:
284 		return false;
285 	}
286 }
287 
288 static const struct regmap_config ads1015_regmap_config = {
289 	.reg_bits = 8,
290 	.val_bits = 16,
291 	.max_register = ADS1015_HI_THRESH_REG,
292 	.writeable_reg = ads1015_is_writeable_reg,
293 };
294 
295 static const struct iio_chan_spec ads1015_channels[] = {
296 	ADS1015_V_DIFF_CHAN(0, 1, ADS1015_AIN0_AIN1),
297 	ADS1015_V_DIFF_CHAN(0, 3, ADS1015_AIN0_AIN3),
298 	ADS1015_V_DIFF_CHAN(1, 3, ADS1015_AIN1_AIN3),
299 	ADS1015_V_DIFF_CHAN(2, 3, ADS1015_AIN2_AIN3),
300 	ADS1015_V_CHAN(0, ADS1015_AIN0),
301 	ADS1015_V_CHAN(1, ADS1015_AIN1),
302 	ADS1015_V_CHAN(2, ADS1015_AIN2),
303 	ADS1015_V_CHAN(3, ADS1015_AIN3),
304 	IIO_CHAN_SOFT_TIMESTAMP(ADS1015_TIMESTAMP),
305 };
306 
307 static const struct iio_chan_spec ads1115_channels[] = {
308 	ADS1115_V_DIFF_CHAN(0, 1, ADS1015_AIN0_AIN1),
309 	ADS1115_V_DIFF_CHAN(0, 3, ADS1015_AIN0_AIN3),
310 	ADS1115_V_DIFF_CHAN(1, 3, ADS1015_AIN1_AIN3),
311 	ADS1115_V_DIFF_CHAN(2, 3, ADS1015_AIN2_AIN3),
312 	ADS1115_V_CHAN(0, ADS1015_AIN0),
313 	ADS1115_V_CHAN(1, ADS1015_AIN1),
314 	ADS1115_V_CHAN(2, ADS1015_AIN2),
315 	ADS1115_V_CHAN(3, ADS1015_AIN3),
316 	IIO_CHAN_SOFT_TIMESTAMP(ADS1015_TIMESTAMP),
317 };
318 
319 static int ads1015_set_power_state(struct ads1015_data *data, bool on)
320 {
321 	int ret;
322 	struct device *dev = regmap_get_device(data->regmap);
323 
324 	if (on) {
325 		ret = pm_runtime_get_sync(dev);
326 		if (ret < 0)
327 			pm_runtime_put_noidle(dev);
328 	} else {
329 		pm_runtime_mark_last_busy(dev);
330 		ret = pm_runtime_put_autosuspend(dev);
331 	}
332 
333 	return ret < 0 ? ret : 0;
334 }
335 
336 static
337 int ads1015_get_adc_result(struct ads1015_data *data, int chan, int *val)
338 {
339 	int ret, pga, dr, dr_old, conv_time;
340 	unsigned int old, mask, cfg;
341 
342 	if (chan < 0 || chan >= ADS1015_CHANNELS)
343 		return -EINVAL;
344 
345 	ret = regmap_read(data->regmap, ADS1015_CFG_REG, &old);
346 	if (ret)
347 		return ret;
348 
349 	pga = data->channel_data[chan].pga;
350 	dr = data->channel_data[chan].data_rate;
351 	mask = ADS1015_CFG_MUX_MASK | ADS1015_CFG_PGA_MASK |
352 		ADS1015_CFG_DR_MASK;
353 	cfg = chan << ADS1015_CFG_MUX_SHIFT | pga << ADS1015_CFG_PGA_SHIFT |
354 		dr << ADS1015_CFG_DR_SHIFT;
355 
356 	if (ads1015_event_channel_enabled(data)) {
357 		mask |= ADS1015_CFG_COMP_QUE_MASK | ADS1015_CFG_COMP_MODE_MASK;
358 		cfg |= data->thresh_data[chan].comp_queue <<
359 				ADS1015_CFG_COMP_QUE_SHIFT |
360 			data->comp_mode <<
361 				ADS1015_CFG_COMP_MODE_SHIFT;
362 	}
363 
364 	cfg = (old & ~mask) | (cfg & mask);
365 	if (old != cfg) {
366 		ret = regmap_write(data->regmap, ADS1015_CFG_REG, cfg);
367 		if (ret)
368 			return ret;
369 		data->conv_invalid = true;
370 	}
371 	if (data->conv_invalid) {
372 		dr_old = (old & ADS1015_CFG_DR_MASK) >> ADS1015_CFG_DR_SHIFT;
373 		conv_time = DIV_ROUND_UP(USEC_PER_SEC, data->data_rate[dr_old]);
374 		conv_time += DIV_ROUND_UP(USEC_PER_SEC, data->data_rate[dr]);
375 		conv_time += conv_time / 10; /* 10% internal clock inaccuracy */
376 		usleep_range(conv_time, conv_time + 1);
377 		data->conv_invalid = false;
378 	}
379 
380 	return regmap_read(data->regmap, ADS1015_CONV_REG, val);
381 }
382 
383 static irqreturn_t ads1015_trigger_handler(int irq, void *p)
384 {
385 	struct iio_poll_func *pf = p;
386 	struct iio_dev *indio_dev = pf->indio_dev;
387 	struct ads1015_data *data = iio_priv(indio_dev);
388 	s16 buf[8]; /* 1x s16 ADC val + 3x s16 padding +  4x s16 timestamp */
389 	int chan, ret, res;
390 
391 	memset(buf, 0, sizeof(buf));
392 
393 	mutex_lock(&data->lock);
394 	chan = find_first_bit(indio_dev->active_scan_mask,
395 			      indio_dev->masklength);
396 	ret = ads1015_get_adc_result(data, chan, &res);
397 	if (ret < 0) {
398 		mutex_unlock(&data->lock);
399 		goto err;
400 	}
401 
402 	buf[0] = res;
403 	mutex_unlock(&data->lock);
404 
405 	iio_push_to_buffers_with_timestamp(indio_dev, buf,
406 					   iio_get_time_ns(indio_dev));
407 
408 err:
409 	iio_trigger_notify_done(indio_dev->trig);
410 
411 	return IRQ_HANDLED;
412 }
413 
414 static int ads1015_set_scale(struct ads1015_data *data,
415 			     struct iio_chan_spec const *chan,
416 			     int scale, int uscale)
417 {
418 	int i;
419 	int fullscale = div_s64((scale * 1000000LL + uscale) <<
420 				(chan->scan_type.realbits - 1), 1000000);
421 
422 	for (i = 0; i < ARRAY_SIZE(ads1015_fullscale_range); i++) {
423 		if (ads1015_fullscale_range[i] == fullscale) {
424 			data->channel_data[chan->address].pga = i;
425 			return 0;
426 		}
427 	}
428 
429 	return -EINVAL;
430 }
431 
432 static int ads1015_set_data_rate(struct ads1015_data *data, int chan, int rate)
433 {
434 	int i;
435 
436 	for (i = 0; i < ARRAY_SIZE(ads1015_data_rate); i++) {
437 		if (data->data_rate[i] == rate) {
438 			data->channel_data[chan].data_rate = i;
439 			return 0;
440 		}
441 	}
442 
443 	return -EINVAL;
444 }
445 
446 static int ads1015_read_raw(struct iio_dev *indio_dev,
447 			    struct iio_chan_spec const *chan, int *val,
448 			    int *val2, long mask)
449 {
450 	int ret, idx;
451 	struct ads1015_data *data = iio_priv(indio_dev);
452 
453 	mutex_lock(&data->lock);
454 	switch (mask) {
455 	case IIO_CHAN_INFO_RAW: {
456 		int shift = chan->scan_type.shift;
457 
458 		ret = iio_device_claim_direct_mode(indio_dev);
459 		if (ret)
460 			break;
461 
462 		if (ads1015_event_channel_enabled(data) &&
463 				data->event_channel != chan->address) {
464 			ret = -EBUSY;
465 			goto release_direct;
466 		}
467 
468 		ret = ads1015_set_power_state(data, true);
469 		if (ret < 0)
470 			goto release_direct;
471 
472 		ret = ads1015_get_adc_result(data, chan->address, val);
473 		if (ret < 0) {
474 			ads1015_set_power_state(data, false);
475 			goto release_direct;
476 		}
477 
478 		*val = sign_extend32(*val >> shift, 15 - shift);
479 
480 		ret = ads1015_set_power_state(data, false);
481 		if (ret < 0)
482 			goto release_direct;
483 
484 		ret = IIO_VAL_INT;
485 release_direct:
486 		iio_device_release_direct_mode(indio_dev);
487 		break;
488 	}
489 	case IIO_CHAN_INFO_SCALE:
490 		idx = data->channel_data[chan->address].pga;
491 		*val = ads1015_fullscale_range[idx];
492 		*val2 = chan->scan_type.realbits - 1;
493 		ret = IIO_VAL_FRACTIONAL_LOG2;
494 		break;
495 	case IIO_CHAN_INFO_SAMP_FREQ:
496 		idx = data->channel_data[chan->address].data_rate;
497 		*val = data->data_rate[idx];
498 		ret = IIO_VAL_INT;
499 		break;
500 	default:
501 		ret = -EINVAL;
502 		break;
503 	}
504 	mutex_unlock(&data->lock);
505 
506 	return ret;
507 }
508 
509 static int ads1015_write_raw(struct iio_dev *indio_dev,
510 			     struct iio_chan_spec const *chan, int val,
511 			     int val2, long mask)
512 {
513 	struct ads1015_data *data = iio_priv(indio_dev);
514 	int ret;
515 
516 	mutex_lock(&data->lock);
517 	switch (mask) {
518 	case IIO_CHAN_INFO_SCALE:
519 		ret = ads1015_set_scale(data, chan, val, val2);
520 		break;
521 	case IIO_CHAN_INFO_SAMP_FREQ:
522 		ret = ads1015_set_data_rate(data, chan->address, val);
523 		break;
524 	default:
525 		ret = -EINVAL;
526 		break;
527 	}
528 	mutex_unlock(&data->lock);
529 
530 	return ret;
531 }
532 
533 static int ads1015_read_event(struct iio_dev *indio_dev,
534 	const struct iio_chan_spec *chan, enum iio_event_type type,
535 	enum iio_event_direction dir, enum iio_event_info info, int *val,
536 	int *val2)
537 {
538 	struct ads1015_data *data = iio_priv(indio_dev);
539 	int ret;
540 	unsigned int comp_queue;
541 	int period;
542 	int dr;
543 
544 	mutex_lock(&data->lock);
545 
546 	switch (info) {
547 	case IIO_EV_INFO_VALUE:
548 		*val = (dir == IIO_EV_DIR_RISING) ?
549 			data->thresh_data[chan->address].high_thresh :
550 			data->thresh_data[chan->address].low_thresh;
551 		ret = IIO_VAL_INT;
552 		break;
553 	case IIO_EV_INFO_PERIOD:
554 		dr = data->channel_data[chan->address].data_rate;
555 		comp_queue = data->thresh_data[chan->address].comp_queue;
556 		period = ads1015_comp_queue[comp_queue] *
557 			USEC_PER_SEC / data->data_rate[dr];
558 
559 		*val = period / USEC_PER_SEC;
560 		*val2 = period % USEC_PER_SEC;
561 		ret = IIO_VAL_INT_PLUS_MICRO;
562 		break;
563 	default:
564 		ret = -EINVAL;
565 		break;
566 	}
567 
568 	mutex_unlock(&data->lock);
569 
570 	return ret;
571 }
572 
573 static int ads1015_write_event(struct iio_dev *indio_dev,
574 	const struct iio_chan_spec *chan, enum iio_event_type type,
575 	enum iio_event_direction dir, enum iio_event_info info, int val,
576 	int val2)
577 {
578 	struct ads1015_data *data = iio_priv(indio_dev);
579 	int realbits = chan->scan_type.realbits;
580 	int ret = 0;
581 	long long period;
582 	int i;
583 	int dr;
584 
585 	mutex_lock(&data->lock);
586 
587 	switch (info) {
588 	case IIO_EV_INFO_VALUE:
589 		if (val >= 1 << (realbits - 1) || val < -1 << (realbits - 1)) {
590 			ret = -EINVAL;
591 			break;
592 		}
593 		if (dir == IIO_EV_DIR_RISING)
594 			data->thresh_data[chan->address].high_thresh = val;
595 		else
596 			data->thresh_data[chan->address].low_thresh = val;
597 		break;
598 	case IIO_EV_INFO_PERIOD:
599 		dr = data->channel_data[chan->address].data_rate;
600 		period = val * USEC_PER_SEC + val2;
601 
602 		for (i = 0; i < ARRAY_SIZE(ads1015_comp_queue) - 1; i++) {
603 			if (period <= ads1015_comp_queue[i] *
604 					USEC_PER_SEC / data->data_rate[dr])
605 				break;
606 		}
607 		data->thresh_data[chan->address].comp_queue = i;
608 		break;
609 	default:
610 		ret = -EINVAL;
611 		break;
612 	}
613 
614 	mutex_unlock(&data->lock);
615 
616 	return ret;
617 }
618 
619 static int ads1015_read_event_config(struct iio_dev *indio_dev,
620 	const struct iio_chan_spec *chan, enum iio_event_type type,
621 	enum iio_event_direction dir)
622 {
623 	struct ads1015_data *data = iio_priv(indio_dev);
624 	int ret = 0;
625 
626 	mutex_lock(&data->lock);
627 	if (data->event_channel == chan->address) {
628 		switch (dir) {
629 		case IIO_EV_DIR_RISING:
630 			ret = 1;
631 			break;
632 		case IIO_EV_DIR_EITHER:
633 			ret = (data->comp_mode == ADS1015_CFG_COMP_MODE_WINDOW);
634 			break;
635 		default:
636 			ret = -EINVAL;
637 			break;
638 		}
639 	}
640 	mutex_unlock(&data->lock);
641 
642 	return ret;
643 }
644 
645 static int ads1015_enable_event_config(struct ads1015_data *data,
646 	const struct iio_chan_spec *chan, int comp_mode)
647 {
648 	int low_thresh = data->thresh_data[chan->address].low_thresh;
649 	int high_thresh = data->thresh_data[chan->address].high_thresh;
650 	int ret;
651 	unsigned int val;
652 
653 	if (ads1015_event_channel_enabled(data)) {
654 		if (data->event_channel != chan->address ||
655 			(data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD &&
656 				comp_mode == ADS1015_CFG_COMP_MODE_WINDOW))
657 			return -EBUSY;
658 
659 		return 0;
660 	}
661 
662 	if (comp_mode == ADS1015_CFG_COMP_MODE_TRAD) {
663 		low_thresh = max(-1 << (chan->scan_type.realbits - 1),
664 				high_thresh - 1);
665 	}
666 	ret = regmap_write(data->regmap, ADS1015_LO_THRESH_REG,
667 			low_thresh << chan->scan_type.shift);
668 	if (ret)
669 		return ret;
670 
671 	ret = regmap_write(data->regmap, ADS1015_HI_THRESH_REG,
672 			high_thresh << chan->scan_type.shift);
673 	if (ret)
674 		return ret;
675 
676 	ret = ads1015_set_power_state(data, true);
677 	if (ret < 0)
678 		return ret;
679 
680 	ads1015_event_channel_enable(data, chan->address, comp_mode);
681 
682 	ret = ads1015_get_adc_result(data, chan->address, &val);
683 	if (ret) {
684 		ads1015_event_channel_disable(data, chan->address);
685 		ads1015_set_power_state(data, false);
686 	}
687 
688 	return ret;
689 }
690 
691 static int ads1015_disable_event_config(struct ads1015_data *data,
692 	const struct iio_chan_spec *chan, int comp_mode)
693 {
694 	int ret;
695 
696 	if (!ads1015_event_channel_enabled(data))
697 		return 0;
698 
699 	if (data->event_channel != chan->address)
700 		return 0;
701 
702 	if (data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD &&
703 			comp_mode == ADS1015_CFG_COMP_MODE_WINDOW)
704 		return 0;
705 
706 	ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG,
707 				ADS1015_CFG_COMP_QUE_MASK,
708 				ADS1015_CFG_COMP_DISABLE <<
709 					ADS1015_CFG_COMP_QUE_SHIFT);
710 	if (ret)
711 		return ret;
712 
713 	ads1015_event_channel_disable(data, chan->address);
714 
715 	return ads1015_set_power_state(data, false);
716 }
717 
718 static int ads1015_write_event_config(struct iio_dev *indio_dev,
719 	const struct iio_chan_spec *chan, enum iio_event_type type,
720 	enum iio_event_direction dir, int state)
721 {
722 	struct ads1015_data *data = iio_priv(indio_dev);
723 	int ret;
724 	int comp_mode = (dir == IIO_EV_DIR_EITHER) ?
725 		ADS1015_CFG_COMP_MODE_WINDOW : ADS1015_CFG_COMP_MODE_TRAD;
726 
727 	mutex_lock(&data->lock);
728 
729 	/* Prevent from enabling both buffer and event at a time */
730 	ret = iio_device_claim_direct_mode(indio_dev);
731 	if (ret) {
732 		mutex_unlock(&data->lock);
733 		return ret;
734 	}
735 
736 	if (state)
737 		ret = ads1015_enable_event_config(data, chan, comp_mode);
738 	else
739 		ret = ads1015_disable_event_config(data, chan, comp_mode);
740 
741 	iio_device_release_direct_mode(indio_dev);
742 	mutex_unlock(&data->lock);
743 
744 	return ret;
745 }
746 
747 static irqreturn_t ads1015_event_handler(int irq, void *priv)
748 {
749 	struct iio_dev *indio_dev = priv;
750 	struct ads1015_data *data = iio_priv(indio_dev);
751 	int val;
752 	int ret;
753 
754 	/* Clear the latched ALERT/RDY pin */
755 	ret = regmap_read(data->regmap, ADS1015_CONV_REG, &val);
756 	if (ret)
757 		return IRQ_HANDLED;
758 
759 	if (ads1015_event_channel_enabled(data)) {
760 		enum iio_event_direction dir;
761 		u64 code;
762 
763 		dir = data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD ?
764 					IIO_EV_DIR_RISING : IIO_EV_DIR_EITHER;
765 		code = IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, data->event_channel,
766 					IIO_EV_TYPE_THRESH, dir);
767 		iio_push_event(indio_dev, code, iio_get_time_ns(indio_dev));
768 	}
769 
770 	return IRQ_HANDLED;
771 }
772 
773 static int ads1015_buffer_preenable(struct iio_dev *indio_dev)
774 {
775 	struct ads1015_data *data = iio_priv(indio_dev);
776 
777 	/* Prevent from enabling both buffer and event at a time */
778 	if (ads1015_event_channel_enabled(data))
779 		return -EBUSY;
780 
781 	return ads1015_set_power_state(iio_priv(indio_dev), true);
782 }
783 
784 static int ads1015_buffer_postdisable(struct iio_dev *indio_dev)
785 {
786 	return ads1015_set_power_state(iio_priv(indio_dev), false);
787 }
788 
789 static const struct iio_buffer_setup_ops ads1015_buffer_setup_ops = {
790 	.preenable	= ads1015_buffer_preenable,
791 	.postenable	= iio_triggered_buffer_postenable,
792 	.predisable	= iio_triggered_buffer_predisable,
793 	.postdisable	= ads1015_buffer_postdisable,
794 	.validate_scan_mask = &iio_validate_scan_mask_onehot,
795 };
796 
797 static IIO_CONST_ATTR_NAMED(ads1015_scale_available, scale_available,
798 	"3 2 1 0.5 0.25 0.125");
799 static IIO_CONST_ATTR_NAMED(ads1115_scale_available, scale_available,
800 	"0.1875 0.125 0.0625 0.03125 0.015625 0.007813");
801 
802 static IIO_CONST_ATTR_NAMED(ads1015_sampling_frequency_available,
803 	sampling_frequency_available, "128 250 490 920 1600 2400 3300");
804 static IIO_CONST_ATTR_NAMED(ads1115_sampling_frequency_available,
805 	sampling_frequency_available, "8 16 32 64 128 250 475 860");
806 
807 static struct attribute *ads1015_attributes[] = {
808 	&iio_const_attr_ads1015_scale_available.dev_attr.attr,
809 	&iio_const_attr_ads1015_sampling_frequency_available.dev_attr.attr,
810 	NULL,
811 };
812 
813 static const struct attribute_group ads1015_attribute_group = {
814 	.attrs = ads1015_attributes,
815 };
816 
817 static struct attribute *ads1115_attributes[] = {
818 	&iio_const_attr_ads1115_scale_available.dev_attr.attr,
819 	&iio_const_attr_ads1115_sampling_frequency_available.dev_attr.attr,
820 	NULL,
821 };
822 
823 static const struct attribute_group ads1115_attribute_group = {
824 	.attrs = ads1115_attributes,
825 };
826 
827 static const struct iio_info ads1015_info = {
828 	.read_raw	= ads1015_read_raw,
829 	.write_raw	= ads1015_write_raw,
830 	.read_event_value = ads1015_read_event,
831 	.write_event_value = ads1015_write_event,
832 	.read_event_config = ads1015_read_event_config,
833 	.write_event_config = ads1015_write_event_config,
834 	.attrs          = &ads1015_attribute_group,
835 };
836 
837 static const struct iio_info ads1115_info = {
838 	.read_raw	= ads1015_read_raw,
839 	.write_raw	= ads1015_write_raw,
840 	.read_event_value = ads1015_read_event,
841 	.write_event_value = ads1015_write_event,
842 	.read_event_config = ads1015_read_event_config,
843 	.write_event_config = ads1015_write_event_config,
844 	.attrs          = &ads1115_attribute_group,
845 };
846 
847 static int ads1015_client_get_channels_config(struct i2c_client *client)
848 {
849 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
850 	struct ads1015_data *data = iio_priv(indio_dev);
851 	struct device *dev = &client->dev;
852 	struct fwnode_handle *node;
853 	int i = -1;
854 
855 	device_for_each_child_node(dev, node) {
856 		u32 pval;
857 		unsigned int channel;
858 		unsigned int pga = ADS1015_DEFAULT_PGA;
859 		unsigned int data_rate = ADS1015_DEFAULT_DATA_RATE;
860 
861 		if (fwnode_property_read_u32(node, "reg", &pval)) {
862 			dev_err(dev, "invalid reg on %pfw\n", node);
863 			continue;
864 		}
865 
866 		channel = pval;
867 		if (channel >= ADS1015_CHANNELS) {
868 			dev_err(dev, "invalid channel index %d on %pfw\n",
869 				channel, node);
870 			continue;
871 		}
872 
873 		if (!fwnode_property_read_u32(node, "ti,gain", &pval)) {
874 			pga = pval;
875 			if (pga > 6) {
876 				dev_err(dev, "invalid gain on %pfw\n", node);
877 				fwnode_handle_put(node);
878 				return -EINVAL;
879 			}
880 		}
881 
882 		if (!fwnode_property_read_u32(node, "ti,datarate", &pval)) {
883 			data_rate = pval;
884 			if (data_rate > 7) {
885 				dev_err(dev, "invalid data_rate on %pfw\n", node);
886 				fwnode_handle_put(node);
887 				return -EINVAL;
888 			}
889 		}
890 
891 		data->channel_data[channel].pga = pga;
892 		data->channel_data[channel].data_rate = data_rate;
893 
894 		i++;
895 	}
896 
897 	return i < 0 ? -EINVAL : 0;
898 }
899 
900 static void ads1015_get_channels_config(struct i2c_client *client)
901 {
902 	unsigned int k;
903 
904 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
905 	struct ads1015_data *data = iio_priv(indio_dev);
906 
907 	if (!ads1015_client_get_channels_config(client))
908 		return;
909 
910 	/* fallback on default configuration */
911 	for (k = 0; k < ADS1015_CHANNELS; ++k) {
912 		data->channel_data[k].pga = ADS1015_DEFAULT_PGA;
913 		data->channel_data[k].data_rate = ADS1015_DEFAULT_DATA_RATE;
914 	}
915 }
916 
917 static int ads1015_set_conv_mode(struct ads1015_data *data, int mode)
918 {
919 	return regmap_update_bits(data->regmap, ADS1015_CFG_REG,
920 				  ADS1015_CFG_MOD_MASK,
921 				  mode << ADS1015_CFG_MOD_SHIFT);
922 }
923 
924 static int ads1015_probe(struct i2c_client *client,
925 			 const struct i2c_device_id *id)
926 {
927 	struct iio_dev *indio_dev;
928 	struct ads1015_data *data;
929 	int ret;
930 	enum chip_ids chip;
931 	int i;
932 
933 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
934 	if (!indio_dev)
935 		return -ENOMEM;
936 
937 	data = iio_priv(indio_dev);
938 	i2c_set_clientdata(client, indio_dev);
939 
940 	mutex_init(&data->lock);
941 
942 	indio_dev->dev.parent = &client->dev;
943 	indio_dev->dev.of_node = client->dev.of_node;
944 	indio_dev->name = ADS1015_DRV_NAME;
945 	indio_dev->modes = INDIO_DIRECT_MODE;
946 
947 	chip = (enum chip_ids)device_get_match_data(&client->dev);
948 	if (chip == ADSXXXX)
949 		chip = id->driver_data;
950 	switch (chip) {
951 	case ADS1015:
952 		indio_dev->channels = ads1015_channels;
953 		indio_dev->num_channels = ARRAY_SIZE(ads1015_channels);
954 		indio_dev->info = &ads1015_info;
955 		data->data_rate = (unsigned int *) &ads1015_data_rate;
956 		break;
957 	case ADS1115:
958 		indio_dev->channels = ads1115_channels;
959 		indio_dev->num_channels = ARRAY_SIZE(ads1115_channels);
960 		indio_dev->info = &ads1115_info;
961 		data->data_rate = (unsigned int *) &ads1115_data_rate;
962 		break;
963 	default:
964 		dev_err(&client->dev, "Unknown chip %d\n", chip);
965 		return -EINVAL;
966 	}
967 
968 	data->event_channel = ADS1015_CHANNELS;
969 	/*
970 	 * Set default lower and upper threshold to min and max value
971 	 * respectively.
972 	 */
973 	for (i = 0; i < ADS1015_CHANNELS; i++) {
974 		int realbits = indio_dev->channels[i].scan_type.realbits;
975 
976 		data->thresh_data[i].low_thresh = -1 << (realbits - 1);
977 		data->thresh_data[i].high_thresh = (1 << (realbits - 1)) - 1;
978 	}
979 
980 	/* we need to keep this ABI the same as used by hwmon ADS1015 driver */
981 	ads1015_get_channels_config(client);
982 
983 	data->regmap = devm_regmap_init_i2c(client, &ads1015_regmap_config);
984 	if (IS_ERR(data->regmap)) {
985 		dev_err(&client->dev, "Failed to allocate register map\n");
986 		return PTR_ERR(data->regmap);
987 	}
988 
989 	ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
990 					      ads1015_trigger_handler,
991 					      &ads1015_buffer_setup_ops);
992 	if (ret < 0) {
993 		dev_err(&client->dev, "iio triggered buffer setup failed\n");
994 		return ret;
995 	}
996 
997 	if (client->irq) {
998 		unsigned long irq_trig =
999 			irqd_get_trigger_type(irq_get_irq_data(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_LOW:
1008 			cfg_comp |= ADS1015_CFG_COMP_POL_LOW <<
1009 					ADS1015_CFG_COMP_POL_SHIFT;
1010 			break;
1011 		case IRQF_TRIGGER_HIGH:
1012 			cfg_comp |= ADS1015_CFG_COMP_POL_HIGH <<
1013 					ADS1015_CFG_COMP_POL_SHIFT;
1014 			break;
1015 		default:
1016 			return -EINVAL;
1017 		}
1018 
1019 		ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG,
1020 					cfg_comp_mask, cfg_comp);
1021 		if (ret)
1022 			return ret;
1023 
1024 		ret = devm_request_threaded_irq(&client->dev, client->irq,
1025 						NULL, ads1015_event_handler,
1026 						irq_trig | IRQF_ONESHOT,
1027 						client->name, indio_dev);
1028 		if (ret)
1029 			return ret;
1030 	}
1031 
1032 	ret = ads1015_set_conv_mode(data, ADS1015_CONTINUOUS);
1033 	if (ret)
1034 		return ret;
1035 
1036 	data->conv_invalid = true;
1037 
1038 	ret = pm_runtime_set_active(&client->dev);
1039 	if (ret)
1040 		return ret;
1041 	pm_runtime_set_autosuspend_delay(&client->dev, ADS1015_SLEEP_DELAY_MS);
1042 	pm_runtime_use_autosuspend(&client->dev);
1043 	pm_runtime_enable(&client->dev);
1044 
1045 	ret = iio_device_register(indio_dev);
1046 	if (ret < 0) {
1047 		dev_err(&client->dev, "Failed to register IIO device\n");
1048 		return ret;
1049 	}
1050 
1051 	return 0;
1052 }
1053 
1054 static int ads1015_remove(struct i2c_client *client)
1055 {
1056 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
1057 	struct ads1015_data *data = iio_priv(indio_dev);
1058 
1059 	iio_device_unregister(indio_dev);
1060 
1061 	pm_runtime_disable(&client->dev);
1062 	pm_runtime_set_suspended(&client->dev);
1063 	pm_runtime_put_noidle(&client->dev);
1064 
1065 	/* power down single shot mode */
1066 	return ads1015_set_conv_mode(data, ADS1015_SINGLESHOT);
1067 }
1068 
1069 #ifdef CONFIG_PM
1070 static int ads1015_runtime_suspend(struct device *dev)
1071 {
1072 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1073 	struct ads1015_data *data = iio_priv(indio_dev);
1074 
1075 	return ads1015_set_conv_mode(data, ADS1015_SINGLESHOT);
1076 }
1077 
1078 static int ads1015_runtime_resume(struct device *dev)
1079 {
1080 	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1081 	struct ads1015_data *data = iio_priv(indio_dev);
1082 	int ret;
1083 
1084 	ret = ads1015_set_conv_mode(data, ADS1015_CONTINUOUS);
1085 	if (!ret)
1086 		data->conv_invalid = true;
1087 
1088 	return ret;
1089 }
1090 #endif
1091 
1092 static const struct dev_pm_ops ads1015_pm_ops = {
1093 	SET_RUNTIME_PM_OPS(ads1015_runtime_suspend,
1094 			   ads1015_runtime_resume, NULL)
1095 };
1096 
1097 static const struct i2c_device_id ads1015_id[] = {
1098 	{"ads1015", ADS1015},
1099 	{"ads1115", ADS1115},
1100 	{}
1101 };
1102 MODULE_DEVICE_TABLE(i2c, ads1015_id);
1103 
1104 static const struct of_device_id ads1015_of_match[] = {
1105 	{
1106 		.compatible = "ti,ads1015",
1107 		.data = (void *)ADS1015
1108 	},
1109 	{
1110 		.compatible = "ti,ads1115",
1111 		.data = (void *)ADS1115
1112 	},
1113 	{}
1114 };
1115 MODULE_DEVICE_TABLE(of, ads1015_of_match);
1116 
1117 static struct i2c_driver ads1015_driver = {
1118 	.driver = {
1119 		.name = ADS1015_DRV_NAME,
1120 		.of_match_table = ads1015_of_match,
1121 		.pm = &ads1015_pm_ops,
1122 	},
1123 	.probe		= ads1015_probe,
1124 	.remove		= ads1015_remove,
1125 	.id_table	= ads1015_id,
1126 };
1127 
1128 module_i2c_driver(ads1015_driver);
1129 
1130 MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
1131 MODULE_DESCRIPTION("Texas Instruments ADS1015 ADC driver");
1132 MODULE_LICENSE("GPL v2");
1133