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 struct ads1015_chip_data {
80 struct iio_chan_spec const *channels;
81 int num_channels;
82 const struct iio_info *info;
83 const int *data_rate;
84 const int data_rate_len;
85 const int *scale;
86 const int scale_len;
87 bool has_comparator;
88 };
89
90 enum ads1015_channels {
91 ADS1015_AIN0_AIN1 = 0,
92 ADS1015_AIN0_AIN3,
93 ADS1015_AIN1_AIN3,
94 ADS1015_AIN2_AIN3,
95 ADS1015_AIN0,
96 ADS1015_AIN1,
97 ADS1015_AIN2,
98 ADS1015_AIN3,
99 ADS1015_TIMESTAMP,
100 };
101
102 static const int ads1015_data_rate[] = {
103 128, 250, 490, 920, 1600, 2400, 3300, 3300
104 };
105
106 static const int ads1115_data_rate[] = {
107 8, 16, 32, 64, 128, 250, 475, 860
108 };
109
110 /*
111 * Translation from PGA bits to full-scale positive and negative input voltage
112 * range in mV
113 */
114 static const int ads1015_fullscale_range[] = {
115 6144, 4096, 2048, 1024, 512, 256, 256, 256
116 };
117
118 static const int ads1015_scale[] = { /* 12bit ADC */
119 256, 11,
120 512, 11,
121 1024, 11,
122 2048, 11,
123 4096, 11,
124 6144, 11
125 };
126
127 static const int ads1115_scale[] = { /* 16bit ADC */
128 256, 15,
129 512, 15,
130 1024, 15,
131 2048, 15,
132 4096, 15,
133 6144, 15
134 };
135
136 /*
137 * Translation from COMP_QUE field value to the number of successive readings
138 * exceed the threshold values before an interrupt is generated
139 */
140 static const int ads1015_comp_queue[] = { 1, 2, 4 };
141
142 static const struct iio_event_spec ads1015_events[] = {
143 {
144 .type = IIO_EV_TYPE_THRESH,
145 .dir = IIO_EV_DIR_RISING,
146 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
147 BIT(IIO_EV_INFO_ENABLE),
148 }, {
149 .type = IIO_EV_TYPE_THRESH,
150 .dir = IIO_EV_DIR_FALLING,
151 .mask_separate = BIT(IIO_EV_INFO_VALUE),
152 }, {
153 .type = IIO_EV_TYPE_THRESH,
154 .dir = IIO_EV_DIR_EITHER,
155 .mask_separate = BIT(IIO_EV_INFO_ENABLE) |
156 BIT(IIO_EV_INFO_PERIOD),
157 },
158 };
159
160 /*
161 * Compile-time check whether _fitbits can accommodate up to _testbits
162 * bits. Returns _fitbits on success, fails to compile otherwise.
163 *
164 * The test works such that it multiplies constant _fitbits by constant
165 * double-negation of size of a non-empty structure, i.e. it multiplies
166 * constant _fitbits by constant 1 in each successful compilation case.
167 * The non-empty structure may contain C11 _Static_assert(), make use of
168 * this and place the kernel variant of static assert in there, so that
169 * it performs the compile-time check for _testbits <= _fitbits. Note
170 * that it is not possible to directly use static_assert in compound
171 * statements, hence this convoluted construct.
172 */
173 #define FIT_CHECK(_testbits, _fitbits) \
174 ( \
175 (_fitbits) * \
176 !!sizeof(struct { \
177 static_assert((_testbits) <= (_fitbits)); \
178 int pad; \
179 }) \
180 )
181
182 #define ADS1015_V_CHAN(_chan, _addr, _realbits, _shift, _event_spec, _num_event_specs) { \
183 .type = IIO_VOLTAGE, \
184 .indexed = 1, \
185 .address = _addr, \
186 .channel = _chan, \
187 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
188 BIT(IIO_CHAN_INFO_SCALE) | \
189 BIT(IIO_CHAN_INFO_SAMP_FREQ), \
190 .info_mask_shared_by_all_available = \
191 BIT(IIO_CHAN_INFO_SCALE) | \
192 BIT(IIO_CHAN_INFO_SAMP_FREQ), \
193 .scan_index = _addr, \
194 .scan_type = { \
195 .sign = 's', \
196 .realbits = (_realbits), \
197 .storagebits = FIT_CHECK((_realbits) + (_shift), 16), \
198 .shift = (_shift), \
199 .endianness = IIO_CPU, \
200 }, \
201 .event_spec = (_event_spec), \
202 .num_event_specs = (_num_event_specs), \
203 .datasheet_name = "AIN"#_chan, \
204 }
205
206 #define ADS1015_V_DIFF_CHAN(_chan, _chan2, _addr, _realbits, _shift, _event_spec, _num_event_specs) { \
207 .type = IIO_VOLTAGE, \
208 .differential = 1, \
209 .indexed = 1, \
210 .address = _addr, \
211 .channel = _chan, \
212 .channel2 = _chan2, \
213 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
214 BIT(IIO_CHAN_INFO_SCALE) | \
215 BIT(IIO_CHAN_INFO_SAMP_FREQ), \
216 .info_mask_shared_by_all_available = \
217 BIT(IIO_CHAN_INFO_SCALE) | \
218 BIT(IIO_CHAN_INFO_SAMP_FREQ), \
219 .scan_index = _addr, \
220 .scan_type = { \
221 .sign = 's', \
222 .realbits = (_realbits), \
223 .storagebits = FIT_CHECK((_realbits) + (_shift), 16), \
224 .shift = (_shift), \
225 .endianness = IIO_CPU, \
226 }, \
227 .event_spec = (_event_spec), \
228 .num_event_specs = (_num_event_specs), \
229 .datasheet_name = "AIN"#_chan"-AIN"#_chan2, \
230 }
231
232 struct ads1015_channel_data {
233 bool enabled;
234 unsigned int pga;
235 unsigned int data_rate;
236 };
237
238 struct ads1015_thresh_data {
239 unsigned int comp_queue;
240 int high_thresh;
241 int low_thresh;
242 };
243
244 struct ads1015_data {
245 struct regmap *regmap;
246 /*
247 * Protects ADC ops, e.g: concurrent sysfs/buffered
248 * data reads, configuration updates
249 */
250 struct mutex lock;
251 struct ads1015_channel_data channel_data[ADS1015_CHANNELS];
252
253 unsigned int event_channel;
254 unsigned int comp_mode;
255 struct ads1015_thresh_data thresh_data[ADS1015_CHANNELS];
256
257 const struct ads1015_chip_data *chip;
258 /*
259 * Set to true when the ADC is switched to the continuous-conversion
260 * mode and exits from a power-down state. This flag is used to avoid
261 * getting the stale result from the conversion register.
262 */
263 bool conv_invalid;
264 };
265
ads1015_event_channel_enabled(struct ads1015_data * data)266 static bool ads1015_event_channel_enabled(struct ads1015_data *data)
267 {
268 return (data->event_channel != ADS1015_CHANNELS);
269 }
270
ads1015_event_channel_enable(struct ads1015_data * data,int chan,int comp_mode)271 static void ads1015_event_channel_enable(struct ads1015_data *data, int chan,
272 int comp_mode)
273 {
274 WARN_ON(ads1015_event_channel_enabled(data));
275
276 data->event_channel = chan;
277 data->comp_mode = comp_mode;
278 }
279
ads1015_event_channel_disable(struct ads1015_data * data,int chan)280 static void ads1015_event_channel_disable(struct ads1015_data *data, int chan)
281 {
282 data->event_channel = ADS1015_CHANNELS;
283 }
284
285 static const struct regmap_range ads1015_writeable_ranges[] = {
286 regmap_reg_range(ADS1015_CFG_REG, ADS1015_HI_THRESH_REG),
287 };
288
289 static const struct regmap_access_table ads1015_writeable_table = {
290 .yes_ranges = ads1015_writeable_ranges,
291 .n_yes_ranges = ARRAY_SIZE(ads1015_writeable_ranges),
292 };
293
294 static const struct regmap_config ads1015_regmap_config = {
295 .reg_bits = 8,
296 .val_bits = 16,
297 .max_register = ADS1015_HI_THRESH_REG,
298 .wr_table = &ads1015_writeable_table,
299 };
300
301 static const struct regmap_range tla2024_writeable_ranges[] = {
302 regmap_reg_range(ADS1015_CFG_REG, ADS1015_CFG_REG),
303 };
304
305 static const struct regmap_access_table tla2024_writeable_table = {
306 .yes_ranges = tla2024_writeable_ranges,
307 .n_yes_ranges = ARRAY_SIZE(tla2024_writeable_ranges),
308 };
309
310 static const struct regmap_config tla2024_regmap_config = {
311 .reg_bits = 8,
312 .val_bits = 16,
313 .max_register = ADS1015_CFG_REG,
314 .wr_table = &tla2024_writeable_table,
315 };
316
317 static const struct iio_chan_spec ads1015_channels[] = {
318 ADS1015_V_DIFF_CHAN(0, 1, ADS1015_AIN0_AIN1, 12, 4,
319 ads1015_events, ARRAY_SIZE(ads1015_events)),
320 ADS1015_V_DIFF_CHAN(0, 3, ADS1015_AIN0_AIN3, 12, 4,
321 ads1015_events, ARRAY_SIZE(ads1015_events)),
322 ADS1015_V_DIFF_CHAN(1, 3, ADS1015_AIN1_AIN3, 12, 4,
323 ads1015_events, ARRAY_SIZE(ads1015_events)),
324 ADS1015_V_DIFF_CHAN(2, 3, ADS1015_AIN2_AIN3, 12, 4,
325 ads1015_events, ARRAY_SIZE(ads1015_events)),
326 ADS1015_V_CHAN(0, ADS1015_AIN0, 12, 4,
327 ads1015_events, ARRAY_SIZE(ads1015_events)),
328 ADS1015_V_CHAN(1, ADS1015_AIN1, 12, 4,
329 ads1015_events, ARRAY_SIZE(ads1015_events)),
330 ADS1015_V_CHAN(2, ADS1015_AIN2, 12, 4,
331 ads1015_events, ARRAY_SIZE(ads1015_events)),
332 ADS1015_V_CHAN(3, ADS1015_AIN3, 12, 4,
333 ads1015_events, ARRAY_SIZE(ads1015_events)),
334 IIO_CHAN_SOFT_TIMESTAMP(ADS1015_TIMESTAMP),
335 };
336
337 static const struct iio_chan_spec ads1115_channels[] = {
338 ADS1015_V_DIFF_CHAN(0, 1, ADS1015_AIN0_AIN1, 16, 0,
339 ads1015_events, ARRAY_SIZE(ads1015_events)),
340 ADS1015_V_DIFF_CHAN(0, 3, ADS1015_AIN0_AIN3, 16, 0,
341 ads1015_events, ARRAY_SIZE(ads1015_events)),
342 ADS1015_V_DIFF_CHAN(1, 3, ADS1015_AIN1_AIN3, 16, 0,
343 ads1015_events, ARRAY_SIZE(ads1015_events)),
344 ADS1015_V_DIFF_CHAN(2, 3, ADS1015_AIN2_AIN3, 16, 0,
345 ads1015_events, ARRAY_SIZE(ads1015_events)),
346 ADS1015_V_CHAN(0, ADS1015_AIN0, 16, 0,
347 ads1015_events, ARRAY_SIZE(ads1015_events)),
348 ADS1015_V_CHAN(1, ADS1015_AIN1, 16, 0,
349 ads1015_events, ARRAY_SIZE(ads1015_events)),
350 ADS1015_V_CHAN(2, ADS1015_AIN2, 16, 0,
351 ads1015_events, ARRAY_SIZE(ads1015_events)),
352 ADS1015_V_CHAN(3, ADS1015_AIN3, 16, 0,
353 ads1015_events, ARRAY_SIZE(ads1015_events)),
354 IIO_CHAN_SOFT_TIMESTAMP(ADS1015_TIMESTAMP),
355 };
356
357 static const struct iio_chan_spec tla2024_channels[] = {
358 ADS1015_V_DIFF_CHAN(0, 1, ADS1015_AIN0_AIN1, 12, 4, NULL, 0),
359 ADS1015_V_DIFF_CHAN(0, 3, ADS1015_AIN0_AIN3, 12, 4, NULL, 0),
360 ADS1015_V_DIFF_CHAN(1, 3, ADS1015_AIN1_AIN3, 12, 4, NULL, 0),
361 ADS1015_V_DIFF_CHAN(2, 3, ADS1015_AIN2_AIN3, 12, 4, NULL, 0),
362 ADS1015_V_CHAN(0, ADS1015_AIN0, 12, 4, NULL, 0),
363 ADS1015_V_CHAN(1, ADS1015_AIN1, 12, 4, NULL, 0),
364 ADS1015_V_CHAN(2, ADS1015_AIN2, 12, 4, NULL, 0),
365 ADS1015_V_CHAN(3, ADS1015_AIN3, 12, 4, NULL, 0),
366 IIO_CHAN_SOFT_TIMESTAMP(ADS1015_TIMESTAMP),
367 };
368
369
370 #ifdef CONFIG_PM
ads1015_set_power_state(struct ads1015_data * data,bool on)371 static int ads1015_set_power_state(struct ads1015_data *data, bool on)
372 {
373 int ret;
374 struct device *dev = regmap_get_device(data->regmap);
375
376 if (on) {
377 ret = pm_runtime_resume_and_get(dev);
378 } else {
379 pm_runtime_mark_last_busy(dev);
380 ret = pm_runtime_put_autosuspend(dev);
381 }
382
383 return ret < 0 ? ret : 0;
384 }
385
386 #else /* !CONFIG_PM */
387
ads1015_set_power_state(struct ads1015_data * data,bool on)388 static int ads1015_set_power_state(struct ads1015_data *data, bool on)
389 {
390 return 0;
391 }
392
393 #endif /* !CONFIG_PM */
394
395 static
ads1015_get_adc_result(struct ads1015_data * data,int chan,int * val)396 int ads1015_get_adc_result(struct ads1015_data *data, int chan, int *val)
397 {
398 const int *data_rate = data->chip->data_rate;
399 int ret, pga, dr, dr_old, conv_time;
400 unsigned int old, mask, cfg;
401
402 if (chan < 0 || chan >= ADS1015_CHANNELS)
403 return -EINVAL;
404
405 ret = regmap_read(data->regmap, ADS1015_CFG_REG, &old);
406 if (ret)
407 return ret;
408
409 pga = data->channel_data[chan].pga;
410 dr = data->channel_data[chan].data_rate;
411 mask = ADS1015_CFG_MUX_MASK | ADS1015_CFG_PGA_MASK |
412 ADS1015_CFG_DR_MASK;
413 cfg = chan << ADS1015_CFG_MUX_SHIFT | pga << ADS1015_CFG_PGA_SHIFT |
414 dr << ADS1015_CFG_DR_SHIFT;
415
416 if (ads1015_event_channel_enabled(data)) {
417 mask |= ADS1015_CFG_COMP_QUE_MASK | ADS1015_CFG_COMP_MODE_MASK;
418 cfg |= data->thresh_data[chan].comp_queue <<
419 ADS1015_CFG_COMP_QUE_SHIFT |
420 data->comp_mode <<
421 ADS1015_CFG_COMP_MODE_SHIFT;
422 }
423
424 cfg = (old & ~mask) | (cfg & mask);
425 if (old != cfg) {
426 ret = regmap_write(data->regmap, ADS1015_CFG_REG, cfg);
427 if (ret)
428 return ret;
429 data->conv_invalid = true;
430 }
431 if (data->conv_invalid) {
432 dr_old = (old & ADS1015_CFG_DR_MASK) >> ADS1015_CFG_DR_SHIFT;
433 conv_time = DIV_ROUND_UP(USEC_PER_SEC, data_rate[dr_old]);
434 conv_time += DIV_ROUND_UP(USEC_PER_SEC, data_rate[dr]);
435 conv_time += conv_time / 10; /* 10% internal clock inaccuracy */
436 usleep_range(conv_time, conv_time + 1);
437 data->conv_invalid = false;
438 }
439
440 return regmap_read(data->regmap, ADS1015_CONV_REG, val);
441 }
442
ads1015_trigger_handler(int irq,void * p)443 static irqreturn_t ads1015_trigger_handler(int irq, void *p)
444 {
445 struct iio_poll_func *pf = p;
446 struct iio_dev *indio_dev = pf->indio_dev;
447 struct ads1015_data *data = iio_priv(indio_dev);
448 /* Ensure natural alignment of timestamp */
449 struct {
450 s16 chan;
451 s64 timestamp __aligned(8);
452 } scan;
453 int chan, ret, res;
454
455 memset(&scan, 0, sizeof(scan));
456
457 mutex_lock(&data->lock);
458 chan = find_first_bit(indio_dev->active_scan_mask,
459 indio_dev->masklength);
460 ret = ads1015_get_adc_result(data, chan, &res);
461 if (ret < 0) {
462 mutex_unlock(&data->lock);
463 goto err;
464 }
465
466 scan.chan = res;
467 mutex_unlock(&data->lock);
468
469 iio_push_to_buffers_with_timestamp(indio_dev, &scan,
470 iio_get_time_ns(indio_dev));
471
472 err:
473 iio_trigger_notify_done(indio_dev->trig);
474
475 return IRQ_HANDLED;
476 }
477
ads1015_set_scale(struct ads1015_data * data,struct iio_chan_spec const * chan,int scale,int uscale)478 static int ads1015_set_scale(struct ads1015_data *data,
479 struct iio_chan_spec const *chan,
480 int scale, int uscale)
481 {
482 int i;
483 int fullscale = div_s64((scale * 1000000LL + uscale) <<
484 (chan->scan_type.realbits - 1), 1000000);
485
486 for (i = 0; i < ARRAY_SIZE(ads1015_fullscale_range); i++) {
487 if (ads1015_fullscale_range[i] == fullscale) {
488 data->channel_data[chan->address].pga = i;
489 return 0;
490 }
491 }
492
493 return -EINVAL;
494 }
495
ads1015_set_data_rate(struct ads1015_data * data,int chan,int rate)496 static int ads1015_set_data_rate(struct ads1015_data *data, int chan, int rate)
497 {
498 int i;
499
500 for (i = 0; i < data->chip->data_rate_len; i++) {
501 if (data->chip->data_rate[i] == rate) {
502 data->channel_data[chan].data_rate = i;
503 return 0;
504 }
505 }
506
507 return -EINVAL;
508 }
509
ads1015_read_avail(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,const int ** vals,int * type,int * length,long mask)510 static int ads1015_read_avail(struct iio_dev *indio_dev,
511 struct iio_chan_spec const *chan,
512 const int **vals, int *type, int *length,
513 long mask)
514 {
515 struct ads1015_data *data = iio_priv(indio_dev);
516
517 if (chan->type != IIO_VOLTAGE)
518 return -EINVAL;
519
520 switch (mask) {
521 case IIO_CHAN_INFO_SCALE:
522 *type = IIO_VAL_FRACTIONAL_LOG2;
523 *vals = data->chip->scale;
524 *length = data->chip->scale_len;
525 return IIO_AVAIL_LIST;
526 case IIO_CHAN_INFO_SAMP_FREQ:
527 *type = IIO_VAL_INT;
528 *vals = data->chip->data_rate;
529 *length = data->chip->data_rate_len;
530 return IIO_AVAIL_LIST;
531 default:
532 return -EINVAL;
533 }
534 }
535
ads1015_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)536 static int ads1015_read_raw(struct iio_dev *indio_dev,
537 struct iio_chan_spec const *chan, int *val,
538 int *val2, long mask)
539 {
540 int ret, idx;
541 struct ads1015_data *data = iio_priv(indio_dev);
542
543 mutex_lock(&data->lock);
544 switch (mask) {
545 case IIO_CHAN_INFO_RAW:
546 ret = iio_device_claim_direct_mode(indio_dev);
547 if (ret)
548 break;
549
550 if (ads1015_event_channel_enabled(data) &&
551 data->event_channel != chan->address) {
552 ret = -EBUSY;
553 goto release_direct;
554 }
555
556 ret = ads1015_set_power_state(data, true);
557 if (ret < 0)
558 goto release_direct;
559
560 ret = ads1015_get_adc_result(data, chan->address, val);
561 if (ret < 0) {
562 ads1015_set_power_state(data, false);
563 goto release_direct;
564 }
565
566 *val = sign_extend32(*val >> chan->scan_type.shift,
567 chan->scan_type.realbits - 1);
568
569 ret = ads1015_set_power_state(data, false);
570 if (ret < 0)
571 goto release_direct;
572
573 ret = IIO_VAL_INT;
574 release_direct:
575 iio_device_release_direct_mode(indio_dev);
576 break;
577 case IIO_CHAN_INFO_SCALE:
578 idx = data->channel_data[chan->address].pga;
579 *val = ads1015_fullscale_range[idx];
580 *val2 = chan->scan_type.realbits - 1;
581 ret = IIO_VAL_FRACTIONAL_LOG2;
582 break;
583 case IIO_CHAN_INFO_SAMP_FREQ:
584 idx = data->channel_data[chan->address].data_rate;
585 *val = data->chip->data_rate[idx];
586 ret = IIO_VAL_INT;
587 break;
588 default:
589 ret = -EINVAL;
590 break;
591 }
592 mutex_unlock(&data->lock);
593
594 return ret;
595 }
596
ads1015_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)597 static int ads1015_write_raw(struct iio_dev *indio_dev,
598 struct iio_chan_spec const *chan, int val,
599 int val2, long mask)
600 {
601 struct ads1015_data *data = iio_priv(indio_dev);
602 int ret;
603
604 mutex_lock(&data->lock);
605 switch (mask) {
606 case IIO_CHAN_INFO_SCALE:
607 ret = ads1015_set_scale(data, chan, val, val2);
608 break;
609 case IIO_CHAN_INFO_SAMP_FREQ:
610 ret = ads1015_set_data_rate(data, chan->address, val);
611 break;
612 default:
613 ret = -EINVAL;
614 break;
615 }
616 mutex_unlock(&data->lock);
617
618 return ret;
619 }
620
ads1015_read_event(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir,enum iio_event_info info,int * val,int * val2)621 static int ads1015_read_event(struct iio_dev *indio_dev,
622 const struct iio_chan_spec *chan, enum iio_event_type type,
623 enum iio_event_direction dir, enum iio_event_info info, int *val,
624 int *val2)
625 {
626 struct ads1015_data *data = iio_priv(indio_dev);
627 int ret;
628 unsigned int comp_queue;
629 int period;
630 int dr;
631
632 mutex_lock(&data->lock);
633
634 switch (info) {
635 case IIO_EV_INFO_VALUE:
636 *val = (dir == IIO_EV_DIR_RISING) ?
637 data->thresh_data[chan->address].high_thresh :
638 data->thresh_data[chan->address].low_thresh;
639 ret = IIO_VAL_INT;
640 break;
641 case IIO_EV_INFO_PERIOD:
642 dr = data->channel_data[chan->address].data_rate;
643 comp_queue = data->thresh_data[chan->address].comp_queue;
644 period = ads1015_comp_queue[comp_queue] *
645 USEC_PER_SEC / data->chip->data_rate[dr];
646
647 *val = period / USEC_PER_SEC;
648 *val2 = period % USEC_PER_SEC;
649 ret = IIO_VAL_INT_PLUS_MICRO;
650 break;
651 default:
652 ret = -EINVAL;
653 break;
654 }
655
656 mutex_unlock(&data->lock);
657
658 return ret;
659 }
660
ads1015_write_event(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir,enum iio_event_info info,int val,int val2)661 static int ads1015_write_event(struct iio_dev *indio_dev,
662 const struct iio_chan_spec *chan, enum iio_event_type type,
663 enum iio_event_direction dir, enum iio_event_info info, int val,
664 int val2)
665 {
666 struct ads1015_data *data = iio_priv(indio_dev);
667 const int *data_rate = data->chip->data_rate;
668 int realbits = chan->scan_type.realbits;
669 int ret = 0;
670 long long period;
671 int i;
672 int dr;
673
674 mutex_lock(&data->lock);
675
676 switch (info) {
677 case IIO_EV_INFO_VALUE:
678 if (val >= 1 << (realbits - 1) || val < -1 << (realbits - 1)) {
679 ret = -EINVAL;
680 break;
681 }
682 if (dir == IIO_EV_DIR_RISING)
683 data->thresh_data[chan->address].high_thresh = val;
684 else
685 data->thresh_data[chan->address].low_thresh = val;
686 break;
687 case IIO_EV_INFO_PERIOD:
688 dr = data->channel_data[chan->address].data_rate;
689 period = val * USEC_PER_SEC + val2;
690
691 for (i = 0; i < ARRAY_SIZE(ads1015_comp_queue) - 1; i++) {
692 if (period <= ads1015_comp_queue[i] *
693 USEC_PER_SEC / data_rate[dr])
694 break;
695 }
696 data->thresh_data[chan->address].comp_queue = i;
697 break;
698 default:
699 ret = -EINVAL;
700 break;
701 }
702
703 mutex_unlock(&data->lock);
704
705 return ret;
706 }
707
ads1015_read_event_config(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir)708 static int ads1015_read_event_config(struct iio_dev *indio_dev,
709 const struct iio_chan_spec *chan, enum iio_event_type type,
710 enum iio_event_direction dir)
711 {
712 struct ads1015_data *data = iio_priv(indio_dev);
713 int ret = 0;
714
715 mutex_lock(&data->lock);
716 if (data->event_channel == chan->address) {
717 switch (dir) {
718 case IIO_EV_DIR_RISING:
719 ret = 1;
720 break;
721 case IIO_EV_DIR_EITHER:
722 ret = (data->comp_mode == ADS1015_CFG_COMP_MODE_WINDOW);
723 break;
724 default:
725 ret = -EINVAL;
726 break;
727 }
728 }
729 mutex_unlock(&data->lock);
730
731 return ret;
732 }
733
ads1015_enable_event_config(struct ads1015_data * data,const struct iio_chan_spec * chan,int comp_mode)734 static int ads1015_enable_event_config(struct ads1015_data *data,
735 const struct iio_chan_spec *chan, int comp_mode)
736 {
737 int low_thresh = data->thresh_data[chan->address].low_thresh;
738 int high_thresh = data->thresh_data[chan->address].high_thresh;
739 int ret;
740 unsigned int val;
741
742 if (ads1015_event_channel_enabled(data)) {
743 if (data->event_channel != chan->address ||
744 (data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD &&
745 comp_mode == ADS1015_CFG_COMP_MODE_WINDOW))
746 return -EBUSY;
747
748 return 0;
749 }
750
751 if (comp_mode == ADS1015_CFG_COMP_MODE_TRAD) {
752 low_thresh = max(-1 << (chan->scan_type.realbits - 1),
753 high_thresh - 1);
754 }
755 ret = regmap_write(data->regmap, ADS1015_LO_THRESH_REG,
756 low_thresh << chan->scan_type.shift);
757 if (ret)
758 return ret;
759
760 ret = regmap_write(data->regmap, ADS1015_HI_THRESH_REG,
761 high_thresh << chan->scan_type.shift);
762 if (ret)
763 return ret;
764
765 ret = ads1015_set_power_state(data, true);
766 if (ret < 0)
767 return ret;
768
769 ads1015_event_channel_enable(data, chan->address, comp_mode);
770
771 ret = ads1015_get_adc_result(data, chan->address, &val);
772 if (ret) {
773 ads1015_event_channel_disable(data, chan->address);
774 ads1015_set_power_state(data, false);
775 }
776
777 return ret;
778 }
779
ads1015_disable_event_config(struct ads1015_data * data,const struct iio_chan_spec * chan,int comp_mode)780 static int ads1015_disable_event_config(struct ads1015_data *data,
781 const struct iio_chan_spec *chan, int comp_mode)
782 {
783 int ret;
784
785 if (!ads1015_event_channel_enabled(data))
786 return 0;
787
788 if (data->event_channel != chan->address)
789 return 0;
790
791 if (data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD &&
792 comp_mode == ADS1015_CFG_COMP_MODE_WINDOW)
793 return 0;
794
795 ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG,
796 ADS1015_CFG_COMP_QUE_MASK,
797 ADS1015_CFG_COMP_DISABLE <<
798 ADS1015_CFG_COMP_QUE_SHIFT);
799 if (ret)
800 return ret;
801
802 ads1015_event_channel_disable(data, chan->address);
803
804 return ads1015_set_power_state(data, false);
805 }
806
ads1015_write_event_config(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,enum iio_event_type type,enum iio_event_direction dir,int state)807 static int ads1015_write_event_config(struct iio_dev *indio_dev,
808 const struct iio_chan_spec *chan, enum iio_event_type type,
809 enum iio_event_direction dir, int state)
810 {
811 struct ads1015_data *data = iio_priv(indio_dev);
812 int ret;
813 int comp_mode = (dir == IIO_EV_DIR_EITHER) ?
814 ADS1015_CFG_COMP_MODE_WINDOW : ADS1015_CFG_COMP_MODE_TRAD;
815
816 mutex_lock(&data->lock);
817
818 /* Prevent from enabling both buffer and event at a time */
819 ret = iio_device_claim_direct_mode(indio_dev);
820 if (ret) {
821 mutex_unlock(&data->lock);
822 return ret;
823 }
824
825 if (state)
826 ret = ads1015_enable_event_config(data, chan, comp_mode);
827 else
828 ret = ads1015_disable_event_config(data, chan, comp_mode);
829
830 iio_device_release_direct_mode(indio_dev);
831 mutex_unlock(&data->lock);
832
833 return ret;
834 }
835
ads1015_event_handler(int irq,void * priv)836 static irqreturn_t ads1015_event_handler(int irq, void *priv)
837 {
838 struct iio_dev *indio_dev = priv;
839 struct ads1015_data *data = iio_priv(indio_dev);
840 int val;
841 int ret;
842
843 /* Clear the latched ALERT/RDY pin */
844 ret = regmap_read(data->regmap, ADS1015_CONV_REG, &val);
845 if (ret)
846 return IRQ_HANDLED;
847
848 if (ads1015_event_channel_enabled(data)) {
849 enum iio_event_direction dir;
850 u64 code;
851
852 dir = data->comp_mode == ADS1015_CFG_COMP_MODE_TRAD ?
853 IIO_EV_DIR_RISING : IIO_EV_DIR_EITHER;
854 code = IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, data->event_channel,
855 IIO_EV_TYPE_THRESH, dir);
856 iio_push_event(indio_dev, code, iio_get_time_ns(indio_dev));
857 }
858
859 return IRQ_HANDLED;
860 }
861
ads1015_buffer_preenable(struct iio_dev * indio_dev)862 static int ads1015_buffer_preenable(struct iio_dev *indio_dev)
863 {
864 struct ads1015_data *data = iio_priv(indio_dev);
865
866 /* Prevent from enabling both buffer and event at a time */
867 if (ads1015_event_channel_enabled(data))
868 return -EBUSY;
869
870 return ads1015_set_power_state(iio_priv(indio_dev), true);
871 }
872
ads1015_buffer_postdisable(struct iio_dev * indio_dev)873 static int ads1015_buffer_postdisable(struct iio_dev *indio_dev)
874 {
875 return ads1015_set_power_state(iio_priv(indio_dev), false);
876 }
877
878 static const struct iio_buffer_setup_ops ads1015_buffer_setup_ops = {
879 .preenable = ads1015_buffer_preenable,
880 .postdisable = ads1015_buffer_postdisable,
881 .validate_scan_mask = &iio_validate_scan_mask_onehot,
882 };
883
884 static const struct iio_info ads1015_info = {
885 .read_avail = ads1015_read_avail,
886 .read_raw = ads1015_read_raw,
887 .write_raw = ads1015_write_raw,
888 .read_event_value = ads1015_read_event,
889 .write_event_value = ads1015_write_event,
890 .read_event_config = ads1015_read_event_config,
891 .write_event_config = ads1015_write_event_config,
892 };
893
894 static const struct iio_info tla2024_info = {
895 .read_avail = ads1015_read_avail,
896 .read_raw = ads1015_read_raw,
897 .write_raw = ads1015_write_raw,
898 };
899
ads1015_client_get_channels_config(struct i2c_client * client)900 static int ads1015_client_get_channels_config(struct i2c_client *client)
901 {
902 struct iio_dev *indio_dev = i2c_get_clientdata(client);
903 struct ads1015_data *data = iio_priv(indio_dev);
904 struct device *dev = &client->dev;
905 struct fwnode_handle *node;
906 int i = -1;
907
908 device_for_each_child_node(dev, node) {
909 u32 pval;
910 unsigned int channel;
911 unsigned int pga = ADS1015_DEFAULT_PGA;
912 unsigned int data_rate = ADS1015_DEFAULT_DATA_RATE;
913
914 if (fwnode_property_read_u32(node, "reg", &pval)) {
915 dev_err(dev, "invalid reg on %pfw\n", node);
916 continue;
917 }
918
919 channel = pval;
920 if (channel >= ADS1015_CHANNELS) {
921 dev_err(dev, "invalid channel index %d on %pfw\n",
922 channel, node);
923 continue;
924 }
925
926 if (!fwnode_property_read_u32(node, "ti,gain", &pval)) {
927 pga = pval;
928 if (pga > 6) {
929 dev_err(dev, "invalid gain on %pfw\n", node);
930 fwnode_handle_put(node);
931 return -EINVAL;
932 }
933 }
934
935 if (!fwnode_property_read_u32(node, "ti,datarate", &pval)) {
936 data_rate = pval;
937 if (data_rate > 7) {
938 dev_err(dev, "invalid data_rate on %pfw\n", node);
939 fwnode_handle_put(node);
940 return -EINVAL;
941 }
942 }
943
944 data->channel_data[channel].pga = pga;
945 data->channel_data[channel].data_rate = data_rate;
946
947 i++;
948 }
949
950 return i < 0 ? -EINVAL : 0;
951 }
952
ads1015_get_channels_config(struct i2c_client * client)953 static void ads1015_get_channels_config(struct i2c_client *client)
954 {
955 unsigned int k;
956
957 struct iio_dev *indio_dev = i2c_get_clientdata(client);
958 struct ads1015_data *data = iio_priv(indio_dev);
959
960 if (!ads1015_client_get_channels_config(client))
961 return;
962
963 /* fallback on default configuration */
964 for (k = 0; k < ADS1015_CHANNELS; ++k) {
965 data->channel_data[k].pga = ADS1015_DEFAULT_PGA;
966 data->channel_data[k].data_rate = ADS1015_DEFAULT_DATA_RATE;
967 }
968 }
969
ads1015_set_conv_mode(struct ads1015_data * data,int mode)970 static int ads1015_set_conv_mode(struct ads1015_data *data, int mode)
971 {
972 return regmap_update_bits(data->regmap, ADS1015_CFG_REG,
973 ADS1015_CFG_MOD_MASK,
974 mode << ADS1015_CFG_MOD_SHIFT);
975 }
976
ads1015_probe(struct i2c_client * client)977 static int ads1015_probe(struct i2c_client *client)
978 {
979 const struct i2c_device_id *id = i2c_client_get_device_id(client);
980 const struct ads1015_chip_data *chip;
981 struct iio_dev *indio_dev;
982 struct ads1015_data *data;
983 int ret;
984 int i;
985
986 chip = device_get_match_data(&client->dev);
987 if (!chip)
988 chip = (const struct ads1015_chip_data *)id->driver_data;
989 if (!chip)
990 return dev_err_probe(&client->dev, -EINVAL, "Unknown chip\n");
991
992 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
993 if (!indio_dev)
994 return -ENOMEM;
995
996 data = iio_priv(indio_dev);
997 i2c_set_clientdata(client, indio_dev);
998
999 mutex_init(&data->lock);
1000
1001 indio_dev->name = ADS1015_DRV_NAME;
1002 indio_dev->modes = INDIO_DIRECT_MODE;
1003
1004 indio_dev->channels = chip->channels;
1005 indio_dev->num_channels = chip->num_channels;
1006 indio_dev->info = chip->info;
1007 data->chip = chip;
1008 data->event_channel = ADS1015_CHANNELS;
1009
1010 /*
1011 * Set default lower and upper threshold to min and max value
1012 * respectively.
1013 */
1014 for (i = 0; i < ADS1015_CHANNELS; i++) {
1015 int realbits = indio_dev->channels[i].scan_type.realbits;
1016
1017 data->thresh_data[i].low_thresh = -1 << (realbits - 1);
1018 data->thresh_data[i].high_thresh = (1 << (realbits - 1)) - 1;
1019 }
1020
1021 /* we need to keep this ABI the same as used by hwmon ADS1015 driver */
1022 ads1015_get_channels_config(client);
1023
1024 data->regmap = devm_regmap_init_i2c(client, chip->has_comparator ?
1025 &ads1015_regmap_config :
1026 &tla2024_regmap_config);
1027 if (IS_ERR(data->regmap)) {
1028 dev_err(&client->dev, "Failed to allocate register map\n");
1029 return PTR_ERR(data->regmap);
1030 }
1031
1032 ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
1033 ads1015_trigger_handler,
1034 &ads1015_buffer_setup_ops);
1035 if (ret < 0) {
1036 dev_err(&client->dev, "iio triggered buffer setup failed\n");
1037 return ret;
1038 }
1039
1040 if (client->irq && chip->has_comparator) {
1041 unsigned long irq_trig =
1042 irqd_get_trigger_type(irq_get_irq_data(client->irq));
1043 unsigned int cfg_comp_mask = ADS1015_CFG_COMP_QUE_MASK |
1044 ADS1015_CFG_COMP_LAT_MASK | ADS1015_CFG_COMP_POL_MASK;
1045 unsigned int cfg_comp =
1046 ADS1015_CFG_COMP_DISABLE << ADS1015_CFG_COMP_QUE_SHIFT |
1047 1 << ADS1015_CFG_COMP_LAT_SHIFT;
1048
1049 switch (irq_trig) {
1050 case IRQF_TRIGGER_LOW:
1051 cfg_comp |= ADS1015_CFG_COMP_POL_LOW <<
1052 ADS1015_CFG_COMP_POL_SHIFT;
1053 break;
1054 case IRQF_TRIGGER_HIGH:
1055 cfg_comp |= ADS1015_CFG_COMP_POL_HIGH <<
1056 ADS1015_CFG_COMP_POL_SHIFT;
1057 break;
1058 default:
1059 return -EINVAL;
1060 }
1061
1062 ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG,
1063 cfg_comp_mask, cfg_comp);
1064 if (ret)
1065 return ret;
1066
1067 ret = devm_request_threaded_irq(&client->dev, client->irq,
1068 NULL, ads1015_event_handler,
1069 irq_trig | IRQF_ONESHOT,
1070 client->name, indio_dev);
1071 if (ret)
1072 return ret;
1073 }
1074
1075 ret = ads1015_set_conv_mode(data, ADS1015_CONTINUOUS);
1076 if (ret)
1077 return ret;
1078
1079 data->conv_invalid = true;
1080
1081 ret = pm_runtime_set_active(&client->dev);
1082 if (ret)
1083 return ret;
1084 pm_runtime_set_autosuspend_delay(&client->dev, ADS1015_SLEEP_DELAY_MS);
1085 pm_runtime_use_autosuspend(&client->dev);
1086 pm_runtime_enable(&client->dev);
1087
1088 ret = iio_device_register(indio_dev);
1089 if (ret < 0) {
1090 dev_err(&client->dev, "Failed to register IIO device\n");
1091 return ret;
1092 }
1093
1094 return 0;
1095 }
1096
ads1015_remove(struct i2c_client * client)1097 static void ads1015_remove(struct i2c_client *client)
1098 {
1099 struct iio_dev *indio_dev = i2c_get_clientdata(client);
1100 struct ads1015_data *data = iio_priv(indio_dev);
1101 int ret;
1102
1103 iio_device_unregister(indio_dev);
1104
1105 pm_runtime_disable(&client->dev);
1106 pm_runtime_set_suspended(&client->dev);
1107
1108 /* power down single shot mode */
1109 ret = ads1015_set_conv_mode(data, ADS1015_SINGLESHOT);
1110 if (ret)
1111 dev_warn(&client->dev, "Failed to power down (%pe)\n",
1112 ERR_PTR(ret));
1113 }
1114
1115 #ifdef CONFIG_PM
ads1015_runtime_suspend(struct device * dev)1116 static int ads1015_runtime_suspend(struct device *dev)
1117 {
1118 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1119 struct ads1015_data *data = iio_priv(indio_dev);
1120
1121 return ads1015_set_conv_mode(data, ADS1015_SINGLESHOT);
1122 }
1123
ads1015_runtime_resume(struct device * dev)1124 static int ads1015_runtime_resume(struct device *dev)
1125 {
1126 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1127 struct ads1015_data *data = iio_priv(indio_dev);
1128 int ret;
1129
1130 ret = ads1015_set_conv_mode(data, ADS1015_CONTINUOUS);
1131 if (!ret)
1132 data->conv_invalid = true;
1133
1134 return ret;
1135 }
1136 #endif
1137
1138 static const struct dev_pm_ops ads1015_pm_ops = {
1139 SET_RUNTIME_PM_OPS(ads1015_runtime_suspend,
1140 ads1015_runtime_resume, NULL)
1141 };
1142
1143 static const struct ads1015_chip_data ads1015_data = {
1144 .channels = ads1015_channels,
1145 .num_channels = ARRAY_SIZE(ads1015_channels),
1146 .info = &ads1015_info,
1147 .data_rate = ads1015_data_rate,
1148 .data_rate_len = ARRAY_SIZE(ads1015_data_rate),
1149 .scale = ads1015_scale,
1150 .scale_len = ARRAY_SIZE(ads1015_scale),
1151 .has_comparator = true,
1152 };
1153
1154 static const struct ads1015_chip_data ads1115_data = {
1155 .channels = ads1115_channels,
1156 .num_channels = ARRAY_SIZE(ads1115_channels),
1157 .info = &ads1015_info,
1158 .data_rate = ads1115_data_rate,
1159 .data_rate_len = ARRAY_SIZE(ads1115_data_rate),
1160 .scale = ads1115_scale,
1161 .scale_len = ARRAY_SIZE(ads1115_scale),
1162 .has_comparator = true,
1163 };
1164
1165 static const struct ads1015_chip_data tla2024_data = {
1166 .channels = tla2024_channels,
1167 .num_channels = ARRAY_SIZE(tla2024_channels),
1168 .info = &tla2024_info,
1169 .data_rate = ads1015_data_rate,
1170 .data_rate_len = ARRAY_SIZE(ads1015_data_rate),
1171 .scale = ads1015_scale,
1172 .scale_len = ARRAY_SIZE(ads1015_scale),
1173 .has_comparator = false,
1174 };
1175
1176 static const struct i2c_device_id ads1015_id[] = {
1177 { "ads1015", (kernel_ulong_t)&ads1015_data },
1178 { "ads1115", (kernel_ulong_t)&ads1115_data },
1179 { "tla2024", (kernel_ulong_t)&tla2024_data },
1180 {}
1181 };
1182 MODULE_DEVICE_TABLE(i2c, ads1015_id);
1183
1184 static const struct of_device_id ads1015_of_match[] = {
1185 { .compatible = "ti,ads1015", .data = &ads1015_data },
1186 { .compatible = "ti,ads1115", .data = &ads1115_data },
1187 { .compatible = "ti,tla2024", .data = &tla2024_data },
1188 {}
1189 };
1190 MODULE_DEVICE_TABLE(of, ads1015_of_match);
1191
1192 static struct i2c_driver ads1015_driver = {
1193 .driver = {
1194 .name = ADS1015_DRV_NAME,
1195 .of_match_table = ads1015_of_match,
1196 .pm = &ads1015_pm_ops,
1197 },
1198 .probe = ads1015_probe,
1199 .remove = ads1015_remove,
1200 .id_table = ads1015_id,
1201 };
1202
1203 module_i2c_driver(ads1015_driver);
1204
1205 MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
1206 MODULE_DESCRIPTION("Texas Instruments ADS1015 ADC driver");
1207 MODULE_LICENSE("GPL v2");
1208