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
80struct 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
91enum 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
103static const int ads1015_data_rate[] = {
104 128, 250, 490, 920, 1600, 2400, 3300, 3300
105};
106
107static 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 */
115static const int ads1015_fullscale_range[] = {
116 6144, 4096, 2048, 1024, 512, 256, 256, 256
117};
118
119static 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
128static 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 */
141static const int ads1015_comp_queue[] = { 1, 2, 4 };
142
143static 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
233struct ads1015_channel_data {
234 bool enabled;
235 unsigned int pga;
236 unsigned int data_rate;
237};
238
239struct ads1015_thresh_data {
240 unsigned int comp_queue;
241 int high_thresh;
242 int low_thresh;
243};
244
245struct 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
267static bool ads1015_event_channel_enabled(struct ads1015_data *data)
268{
269 return (data->event_channel != ADS1015_CHANNELS);
270}
271
272static 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
281static void ads1015_event_channel_disable(struct ads1015_data *data, int chan)
282{
283 data->event_channel = ADS1015_CHANNELS;
284}
285
286static const struct regmap_range ads1015_writeable_ranges[] = {
287 regmap_reg_range(ADS1015_CFG_REG, ADS1015_HI_THRESH_REG),
288};
289
290static 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
295static 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
302static const struct regmap_range tla2024_writeable_ranges[] = {
303 regmap_reg_range(ADS1015_CFG_REG, ADS1015_CFG_REG),
304};
305
306static 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
311static 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
318static 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
338static 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
358static 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
372static int ads1015_set_power_state(struct ads1015_data *data, bool on)
373{
374 int ret;
375 struct device *dev = regmap_get_device(map: 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
387static int ads1015_set_power_state(struct ads1015_data *data, bool on)
388{
389 return 0;
390}
391
392#endif /* !CONFIG_PM */
393
394static
395int 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(map: data->regmap, ADS1015_CFG_REG, val: &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(map: data->regmap, ADS1015_CFG_REG, val: 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(min: conv_time, max: conv_time + 1);
436 data->conv_invalid = false;
437 }
438
439 return regmap_read(map: data->regmap, ADS1015_CONV_REG, val);
440}
441
442static 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(addr: indio_dev->active_scan_mask,
456 size: iio_get_masklength(indio_dev));
457 ret = ads1015_get_adc_result(data, chan, val: &res);
458 if (ret < 0) {
459 mutex_unlock(lock: &data->lock);
460 goto err;
461 }
462
463 scan.chan = res;
464 mutex_unlock(lock: &data->lock);
465
466 iio_push_to_buffers_with_ts(indio_dev, data: &scan, data_total_len: sizeof(scan),
467 timestamp: iio_get_time_ns(indio_dev));
468
469err:
470 iio_trigger_notify_done(trig: indio_dev->trig);
471
472 return IRQ_HANDLED;
473}
474
475static 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(dividend: (scale * 1000000LL + uscale) <<
481 (chan->scan_type.realbits - 1), divisor: 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
493static 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
507static 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
533static 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, on: true);
543 if (ret < 0)
544 return ret;
545
546 ret = ads1015_get_adc_result(data, chan: chan->address, val);
547 if (ret < 0) {
548 ads1015_set_power_state(data, on: false);
549 return ret;
550 }
551
552 *val = sign_extend32(value: *val >> chan->scan_type.shift,
553 index: chan->scan_type.realbits - 1);
554
555 return ads1015_set_power_state(data, on: false);
556}
557
558static 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)(T: &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
590static 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)(T: &data->lock);
597 switch (mask) {
598 case IIO_CHAN_INFO_SCALE:
599 return ads1015_set_scale(data, chan, scale: val, uscale: val2);
600 case IIO_CHAN_INFO_SAMP_FREQ:
601 return ads1015_set_data_rate(data, chan: chan->address, rate: val);
602 default:
603 return -EINVAL;
604 }
605}
606
607static 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)(T: &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
639static 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)(T: &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
679static 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)(T: &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
699static 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(map: data->regmap, ADS1015_LO_THRESH_REG,
721 val: low_thresh << chan->scan_type.shift);
722 if (ret)
723 return ret;
724
725 ret = regmap_write(map: data->regmap, ADS1015_HI_THRESH_REG,
726 val: high_thresh << chan->scan_type.shift);
727 if (ret)
728 return ret;
729
730 ret = ads1015_set_power_state(data, on: true);
731 if (ret < 0)
732 return ret;
733
734 ads1015_event_channel_enable(data, chan: chan->address, comp_mode);
735
736 ret = ads1015_get_adc_result(data, chan: chan->address, val: &val);
737 if (ret) {
738 ads1015_event_channel_disable(data, chan: chan->address);
739 ads1015_set_power_state(data, on: false);
740 }
741
742 return ret;
743}
744
745static 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(map: 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: chan->address);
768
769 return ads1015_set_power_state(data, on: false);
770}
771
772static 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)(T: &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
796static 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(map: data->regmap, ADS1015_CONV_REG, val: &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, ev_code: code, timestamp: iio_get_time_ns(indio_dev));
817 }
818
819 return IRQ_HANDLED;
820}
821
822static 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(data: iio_priv(indio_dev), on: true);
831}
832
833static int ads1015_buffer_postdisable(struct iio_dev *indio_dev)
834{
835 return ads1015_set_power_state(data: iio_priv(indio_dev), on: false);
836}
837
838static 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
844static 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
854static 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
860static 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(fwnode: node, propname: "reg", val: &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(fwnode: node, propname: "ti,gain", val: &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(fwnode: node, propname: "ti,datarate", val: &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
910static 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
927static int ads1015_set_conv_mode(struct ads1015_data *data, int mode)
928{
929 return regmap_update_bits(map: data->regmap, ADS1015_CFG_REG,
930 ADS1015_CFG_MOD_MASK,
931 val: mode << ADS1015_CFG_MOD_SHIFT);
932}
933
934static 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(dev: &client->dev, err: -EINVAL, fmt: "Unknown chip\n");
945
946 indio_dev = devm_iio_device_alloc(parent: &client->dev, sizeof_priv: sizeof(*data));
947 if (!indio_dev)
948 return -ENOMEM;
949
950 data = iio_priv(indio_dev);
951 i2c_set_clientdata(client, data: 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(ptr: data->regmap)) {
982 dev_err(&client->dev, "Failed to allocate register map\n");
983 return PTR_ERR(ptr: 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(irq: 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(map: data->regmap, ADS1015_CFG_REG,
1018 mask: cfg_comp_mask, val: cfg_comp);
1019 if (ret)
1020 return ret;
1021
1022 ret = devm_request_threaded_irq(dev: &client->dev, irq: client->irq,
1023 NULL, thread_fn: ads1015_event_handler,
1024 irqflags: irq_trig | IRQF_ONESHOT,
1025 devname: client->name, dev_id: 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(dev: &client->dev);
1037 if (ret)
1038 return ret;
1039 pm_runtime_set_autosuspend_delay(dev: &client->dev, ADS1015_SLEEP_DELAY_MS);
1040 pm_runtime_use_autosuspend(dev: &client->dev);
1041 pm_runtime_enable(dev: &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
1052static 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(dev: &client->dev);
1061 pm_runtime_set_suspended(dev: &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
1071static 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
1079static 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
1093static const struct dev_pm_ops ads1015_pm_ops = {
1094 SET_RUNTIME_PM_OPS(ads1015_runtime_suspend,
1095 ads1015_runtime_resume, NULL)
1096};
1097
1098static 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
1109static 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
1120static 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
1131static 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};
1137MODULE_DEVICE_TABLE(i2c, ads1015_id);
1138
1139static 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};
1145MODULE_DEVICE_TABLE(of, ads1015_of_match);
1146
1147static 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
1158module_i2c_driver(ads1015_driver);
1159
1160MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
1161MODULE_DESCRIPTION("Texas Instruments ADS1015 ADC driver");
1162MODULE_LICENSE("GPL v2");
1163

source code of linux/drivers/iio/adc/ti-ads1015.c