1 /* TI ADS1X1X ADC
2  *
3  * Copyright (c) 2021 Facebook, Inc
4  *
5  * SPDX-License-Identifier: Apache-2.0
6  */
7 
8 #include <stdbool.h>
9 #include <zephyr/device.h>
10 #include <zephyr/devicetree.h>
11 #include <zephyr/drivers/adc.h>
12 #include <zephyr/logging/log.h>
13 #include <zephyr/drivers/i2c.h>
14 #include <zephyr/kernel.h>
15 #include <zephyr/sys/byteorder.h>
16 #include <zephyr/sys/util.h>
17 
18 #define ADC_CONTEXT_USES_KERNEL_TIMER
19 #include "adc_context.h"
20 
21 LOG_MODULE_REGISTER(ADS1X1X, CONFIG_ADC_LOG_LEVEL);
22 
23 #define ADS1X1X_CONFIG_OS BIT(15)
24 #define ADS1X1X_CONFIG_MUX(x) ((x) << 12)
25 #define ADS1X1X_CONFIG_PGA(x) ((x) << 9)
26 #define ADS1X1X_CONFIG_MODE BIT(8)
27 #define ADS1X1X_CONFIG_DR(x) ((x) << 5)
28 #define ADS1X1X_CONFIG_COMP_MODE BIT(4)
29 #define ADS1X1X_CONFIG_COMP_POL BIT(3)
30 #define ADS1X1X_CONFIG_COMP_LAT BIT(2)
31 #define ADS1X1X_CONFIG_COMP_QUE(x) (x)
32 
33 enum ads1x1x_reg {
34 	ADS1X1X_REG_CONV = 0x00,
35 	ADS1X1X_REG_CONFIG = 0x01,
36 	ADS1X1X_REG_LO_THRESH = 0x02,
37 	ADS1X1X_REG_HI_THRESH = 0x03,
38 };
39 
40 enum {
41 	ADS1X15_CONFIG_MUX_DIFF_0_1 = 0,
42 	ADS1X15_CONFIG_MUX_DIFF_0_3 = 1,
43 	ADS1X15_CONFIG_MUX_DIFF_1_3 = 2,
44 	ADS1X15_CONFIG_MUX_DIFF_2_3 = 3,
45 	ADS1X15_CONFIG_MUX_SINGLE_0 = 4,
46 	ADS1X15_CONFIG_MUX_SINGLE_1 = 5,
47 	ADS1X15_CONFIG_MUX_SINGLE_2 = 6,
48 	ADS1X15_CONFIG_MUX_SINGLE_3 = 7,
49 };
50 
51 enum {
52 	/* ADS111X, ADS101X samples per second */
53 	/* 8, 128 samples per second */
54 	ADS1X1X_CONFIG_DR_8_128 = 0,
55 	/* 16, 250 samples per second */
56 	ADS1X1X_CONFIG_DR_16_250 = 1,
57 	/* 32, 490 samples per second */
58 	ADS1X1X_CONFIG_DR_32_490 = 2,
59 	/* 64, 920 samples per second */
60 	ADS1X1X_CONFIG_DR_64_920 = 3,
61 	/* 128, 1600 samples per second (default) */
62 	ADS1X1X_CONFIG_DR_128_1600 = 4,
63 	/* 250, 2400 samples per second */
64 	ADS1X1X_CONFIG_DR_250_2400 = 5,
65 	/* 475, 3300 samples per second */
66 	ADS1X1X_CONFIG_DR_475_3300 = 6,
67 	/* 860, 3300 samples per second */
68 	ADS1X1X_CONFIG_DR_860_3300 = 7,
69 	/* Default data rate */
70 	ADS1X1X_CONFIG_DR_DEFAULT = ADS1X1X_CONFIG_DR_128_1600
71 };
72 
73 enum {
74 	/* +/-6.144V range = Gain 1/3 */
75 	ADS1X1X_CONFIG_PGA_6144 = 0,
76 	/* +/-4.096V range = Gain 1/2 */
77 	ADS1X1X_CONFIG_PGA_4096 = 1,
78 	/* +/-2.048V range = Gain 1 (default) */
79 	ADS1X1X_CONFIG_PGA_2048 = 2,
80 	/* +/-1.024V range = Gain 2 */
81 	ADS1X1X_CONFIG_PGA_1024 = 3,
82 	/* +/-0.512V range = Gain 4 */
83 	ADS1X1X_CONFIG_PGA_512 = 4,
84 	/* +/-0.256V range = Gain 8 */
85 	ADS1X1X_CONFIG_PGA_256 = 5
86 };
87 
88 enum {
89 	ADS1X1X_CONFIG_MODE_CONTINUOUS = 0,
90 	ADS1X1X_CONFIG_MODE_SINGLE_SHOT = 1,
91 };
92 
93 enum {
94 	/* Traditional comparator with hysteresis (default) */
95 	ADS1X1X_CONFIG_COMP_MODE_TRADITIONAL = 0,
96 	/* Window comparator */
97 	ADS1X1X_CONFIG_COMP_MODE_WINDOW = 1
98 };
99 
100 enum {
101 	/* ALERT/RDY pin is low when active (default) */
102 	ADS1X1X_CONFIG_COMP_POLARITY_ACTIVE_LO = 0,
103 	/* ALERT/RDY pin is high when active */
104 	ADS1X1X_CONFIG_COMP_POLARITY_ACTIVE_HI = 1
105 };
106 
107 enum {
108 	/* Non-latching comparator (default) */
109 	ADS1X1X_CONFIG_COMP_NON_LATCHING = 0,
110 	/* Latching comparator */
111 	ADS1X1X_CONFIG_COMP_LATCHING = 1
112 };
113 
114 enum {
115 	/* Assert ALERT/RDY after one conversions */
116 	ADS1X1X_CONFIG_COMP_QUEUE_1 = 0,
117 	/* Assert ALERT/RDY after two conversions */
118 	ADS1X1X_CONFIG_COMP_QUEUE_2 = 1,
119 	/* Assert ALERT/RDY after four conversions */
120 	ADS1X1X_CONFIG_COMP_QUEUE_4 = 2,
121 	/* Disable the comparator and put ALERT/RDY in high state (default) */
122 	ADS1X1X_CONFIG_COMP_QUEUE_NONE = 3
123 };
124 
125 struct ads1x1x_config {
126 	struct i2c_dt_spec bus;
127 	const uint32_t odr_delay[8];
128 	uint8_t resolution;
129 	bool multiplexer;
130 	bool pga;
131 };
132 
133 struct ads1x1x_data {
134 	const struct device *dev;
135 	struct adc_context ctx;
136 	k_timeout_t ready_time;
137 	struct k_sem acq_sem;
138 	int16_t *buffer;
139 	int16_t *repeat_buffer;
140 	struct k_thread thread;
141 	bool differential;
142 
143 	K_KERNEL_STACK_MEMBER(stack, CONFIG_ADC_ADS1X1X_ACQUISITION_THREAD_STACK_SIZE);
144 };
145 
ads1x1x_read_reg(const struct device * dev,enum ads1x1x_reg reg_addr,uint16_t * buf)146 static int ads1x1x_read_reg(const struct device *dev, enum ads1x1x_reg reg_addr, uint16_t *buf)
147 {
148 	const struct ads1x1x_config *config = dev->config;
149 	uint16_t reg_val;
150 	int ret;
151 
152 	ret = i2c_burst_read_dt(&config->bus, reg_addr, (uint8_t *)&reg_val, sizeof(reg_val));
153 	if (ret != 0) {
154 		LOG_ERR("ADS1X1X[0x%X]: error reading register 0x%X (%d)", config->bus.addr,
155 			reg_addr, ret);
156 		return ret;
157 	}
158 
159 	*buf = sys_be16_to_cpu(reg_val);
160 
161 	return 0;
162 }
163 
ads1x1x_write_reg(const struct device * dev,enum ads1x1x_reg reg_addr,uint16_t reg_val)164 static int ads1x1x_write_reg(const struct device *dev, enum ads1x1x_reg reg_addr, uint16_t reg_val)
165 {
166 	const struct ads1x1x_config *config = dev->config;
167 	uint8_t buf[3];
168 	int ret;
169 
170 	buf[0] = reg_addr;
171 	sys_put_be16(reg_val, &buf[1]);
172 
173 	ret = i2c_write_dt(&config->bus, buf, sizeof(buf));
174 
175 	if (ret != 0) {
176 		LOG_ERR("ADS1X1X[0x%X]: error writing register 0x%X (%d)", config->bus.addr,
177 			reg_addr, ret);
178 		return ret;
179 	}
180 
181 	return 0;
182 }
183 
ads1x1x_start_conversion(const struct device * dev)184 static int ads1x1x_start_conversion(const struct device *dev)
185 {
186 	/* send start sampling command */
187 	uint16_t config;
188 	int ret;
189 
190 	ret = ads1x1x_read_reg(dev, ADS1X1X_REG_CONFIG, &config);
191 	if (ret != 0) {
192 		return ret;
193 	}
194 	config |= ADS1X1X_CONFIG_OS;
195 	ret = ads1x1x_write_reg(dev, ADS1X1X_REG_CONFIG, config);
196 
197 	return ret;
198 }
199 
ads1x1x_acq_time_to_dr(const struct device * dev,uint16_t acq_time)200 static inline int ads1x1x_acq_time_to_dr(const struct device *dev, uint16_t acq_time)
201 {
202 	struct ads1x1x_data *data = dev->data;
203 	const struct ads1x1x_config *ads_config = dev->config;
204 	const uint32_t *odr_delay = ads_config->odr_delay;
205 	uint32_t odr_delay_us = 0;
206 	int odr = -EINVAL;
207 	uint16_t acq_value = ADC_ACQ_TIME_VALUE(acq_time);
208 
209 	/* The ADS1x1x uses samples per seconds units with the lowest being 8SPS
210 	 * and with acquisition_time only having 14b for time, this will not fit
211 	 * within here for microsecond units. Use Tick units and allow the user to
212 	 * specify the ODR directly.
213 	 */
214 	if (acq_time != ADC_ACQ_TIME_DEFAULT && ADC_ACQ_TIME_UNIT(acq_time) != ADC_ACQ_TIME_TICKS) {
215 		return -EINVAL;
216 	}
217 
218 	if (acq_time == ADC_ACQ_TIME_DEFAULT) {
219 		odr = ADS1X1X_CONFIG_DR_DEFAULT;
220 		odr_delay_us = odr_delay[ADS1X1X_CONFIG_DR_DEFAULT];
221 	} else {
222 		switch (acq_value) {
223 		case ADS1X1X_CONFIG_DR_8_128:
224 			odr = ADS1X1X_CONFIG_DR_8_128;
225 			odr_delay_us = odr_delay[ADS1X1X_CONFIG_DR_8_128];
226 			break;
227 		case ADS1X1X_CONFIG_DR_16_250:
228 			odr = ADS1X1X_CONFIG_DR_16_250;
229 			odr_delay_us = odr_delay[ADS1X1X_CONFIG_DR_16_250];
230 			break;
231 		case ADS1X1X_CONFIG_DR_32_490:
232 			odr = ADS1X1X_CONFIG_DR_32_490;
233 			odr_delay_us = odr_delay[ADS1X1X_CONFIG_DR_32_490];
234 			break;
235 		case ADS1X1X_CONFIG_DR_64_920:
236 			odr = ADS1X1X_CONFIG_DR_64_920;
237 			odr_delay_us = odr_delay[ADS1X1X_CONFIG_DR_64_920];
238 			break;
239 		case ADS1X1X_CONFIG_DR_128_1600:
240 			odr = ADS1X1X_CONFIG_DR_128_1600;
241 			odr_delay_us = odr_delay[ADS1X1X_CONFIG_DR_128_1600];
242 			break;
243 		case ADS1X1X_CONFIG_DR_250_2400:
244 			odr = ADS1X1X_CONFIG_DR_250_2400;
245 			odr_delay_us = odr_delay[ADS1X1X_CONFIG_DR_250_2400];
246 			break;
247 		case ADS1X1X_CONFIG_DR_475_3300:
248 			odr = ADS1X1X_CONFIG_DR_475_3300;
249 			odr_delay_us = odr_delay[ADS1X1X_CONFIG_DR_475_3300];
250 			break;
251 		case ADS1X1X_CONFIG_DR_860_3300:
252 			odr = ADS1X1X_CONFIG_DR_860_3300;
253 			odr_delay_us = odr_delay[ADS1X1X_CONFIG_DR_860_3300];
254 			break;
255 		default:
256 			break;
257 		}
258 	}
259 
260 	/* As per the datasheet, 25us is needed to wake-up from power down mode
261 	 */
262 	odr_delay_us += 25;
263 	data->ready_time = K_USEC(odr_delay_us);
264 
265 	return odr;
266 }
267 
ads1x1x_wait_data_ready(const struct device * dev)268 static int ads1x1x_wait_data_ready(const struct device *dev)
269 {
270 	int rc;
271 	struct ads1x1x_data *data = dev->data;
272 
273 	k_sleep(data->ready_time);
274 	uint16_t status = 0;
275 
276 	rc = ads1x1x_read_reg(dev, ADS1X1X_REG_CONFIG, &status);
277 	if (rc != 0) {
278 		return rc;
279 	}
280 
281 	while (!(status & ADS1X1X_CONFIG_OS)) {
282 		k_sleep(K_USEC(100));
283 		rc = ads1x1x_read_reg(dev, ADS1X1X_REG_CONFIG, &status);
284 		if (rc != 0) {
285 			return rc;
286 		}
287 	}
288 
289 	return rc;
290 }
291 
ads1x1x_channel_setup(const struct device * dev,const struct adc_channel_cfg * channel_cfg)292 static int ads1x1x_channel_setup(const struct device *dev,
293 				 const struct adc_channel_cfg *channel_cfg)
294 {
295 	const struct ads1x1x_config *ads_config = dev->config;
296 	struct ads1x1x_data *data = dev->data;
297 	uint16_t config = 0;
298 	int dr = 0;
299 
300 	if (channel_cfg->channel_id != 0) {
301 		LOG_ERR("unsupported channel id '%d'", channel_cfg->channel_id);
302 		return -ENOTSUP;
303 	}
304 
305 	if (channel_cfg->reference != ADC_REF_INTERNAL) {
306 		LOG_ERR("unsupported channel reference type '%d'", channel_cfg->reference);
307 		return -ENOTSUP;
308 	}
309 
310 	if (ads_config->multiplexer) {
311 		/* the device has an input multiplexer */
312 		if (channel_cfg->differential) {
313 			if (channel_cfg->input_positive == 0 && channel_cfg->input_negative == 1) {
314 				config |= ADS1X1X_CONFIG_MUX(ADS1X15_CONFIG_MUX_DIFF_0_1);
315 			} else if (channel_cfg->input_positive == 0 &&
316 				   channel_cfg->input_negative == 3) {
317 				config |= ADS1X1X_CONFIG_MUX(ADS1X15_CONFIG_MUX_DIFF_0_3);
318 			} else if (channel_cfg->input_positive == 1 &&
319 				   channel_cfg->input_negative == 3) {
320 				config |= ADS1X1X_CONFIG_MUX(ADS1X15_CONFIG_MUX_DIFF_1_3);
321 			} else if (channel_cfg->input_positive == 2 &&
322 				   channel_cfg->input_negative == 3) {
323 				config |= ADS1X1X_CONFIG_MUX(ADS1X15_CONFIG_MUX_DIFF_2_3);
324 			} else {
325 				LOG_ERR("unsupported input positive '%d' and input negative '%d'",
326 					channel_cfg->input_positive, channel_cfg->input_negative);
327 				return -ENOTSUP;
328 			}
329 		} else {
330 			if (channel_cfg->input_positive == 0) {
331 				config |= ADS1X1X_CONFIG_MUX(ADS1X15_CONFIG_MUX_SINGLE_0);
332 			} else if (channel_cfg->input_positive == 1) {
333 				config |= ADS1X1X_CONFIG_MUX(ADS1X15_CONFIG_MUX_SINGLE_1);
334 			} else if (channel_cfg->input_positive == 2) {
335 				config |= ADS1X1X_CONFIG_MUX(ADS1X15_CONFIG_MUX_SINGLE_2);
336 			} else if (channel_cfg->input_positive == 3) {
337 				config |= ADS1X1X_CONFIG_MUX(ADS1X15_CONFIG_MUX_SINGLE_3);
338 			} else {
339 				LOG_ERR("unsupported input positive '%d'",
340 					channel_cfg->input_positive);
341 				return -ENOTSUP;
342 			}
343 		}
344 	} else {
345 		/* only differential supported without multiplexer */
346 		if (!((channel_cfg->differential) &&
347 		      (channel_cfg->input_positive == 0 && channel_cfg->input_negative == 1))) {
348 			LOG_ERR("unsupported input positive '%d' and input negative '%d'",
349 				channel_cfg->input_positive, channel_cfg->input_negative);
350 			return -ENOTSUP;
351 		}
352 	}
353 	/* store differential mode to determine supported resolution */
354 	data->differential = channel_cfg->differential;
355 
356 	dr = ads1x1x_acq_time_to_dr(dev, channel_cfg->acquisition_time);
357 	if (dr < 0) {
358 		LOG_ERR("unsupported channel acquisition time 0x%02x",
359 			channel_cfg->acquisition_time);
360 		return -ENOTSUP;
361 	}
362 
363 	config |= ADS1X1X_CONFIG_DR(dr);
364 
365 	if (ads_config->pga) {
366 		/* programmable gain amplifier support */
367 		switch (channel_cfg->gain) {
368 		case ADC_GAIN_1_3:
369 			config |= ADS1X1X_CONFIG_PGA(ADS1X1X_CONFIG_PGA_6144);
370 			break;
371 		case ADC_GAIN_1_2:
372 			config |= ADS1X1X_CONFIG_PGA(ADS1X1X_CONFIG_PGA_4096);
373 			break;
374 		case ADC_GAIN_1:
375 			config |= ADS1X1X_CONFIG_PGA(ADS1X1X_CONFIG_PGA_2048);
376 			break;
377 		case ADC_GAIN_2:
378 			config |= ADS1X1X_CONFIG_PGA(ADS1X1X_CONFIG_PGA_1024);
379 			break;
380 		case ADC_GAIN_4:
381 			config |= ADS1X1X_CONFIG_PGA(ADS1X1X_CONFIG_PGA_512);
382 			break;
383 		case ADC_GAIN_8:
384 			config |= ADS1X1X_CONFIG_PGA(ADS1X1X_CONFIG_PGA_256);
385 			break;
386 		default:
387 			LOG_ERR("unsupported channel gain '%d'", channel_cfg->gain);
388 			return -ENOTSUP;
389 		}
390 	} else {
391 		/* no programmable gain amplifier, so only allow ADC_GAIN_1 */
392 		if (channel_cfg->gain != ADC_GAIN_1) {
393 			LOG_ERR("unsupported channel gain '%d'", channel_cfg->gain);
394 			return -ENOTSUP;
395 		}
396 	}
397 
398 	/* Only single shot supported */
399 	config |= ADS1X1X_CONFIG_MODE;
400 
401 	/* disable comparator */
402 	config |= ADS1X1X_CONFIG_COMP_MODE;
403 
404 	return ads1x1x_write_reg(dev, ADS1X1X_REG_CONFIG, config);
405 }
406 
ads1x1x_validate_buffer_size(const struct adc_sequence * sequence)407 static int ads1x1x_validate_buffer_size(const struct adc_sequence *sequence)
408 {
409 	size_t needed = sizeof(int16_t);
410 
411 	if (sequence->options) {
412 		needed *= (1 + sequence->options->extra_samplings);
413 	}
414 
415 	if (sequence->buffer_size < needed) {
416 		return -ENOMEM;
417 	}
418 
419 	return 0;
420 }
421 
ads1x1x_validate_sequence(const struct device * dev,const struct adc_sequence * sequence)422 static int ads1x1x_validate_sequence(const struct device *dev, const struct adc_sequence *sequence)
423 {
424 	const struct ads1x1x_config *config = dev->config;
425 	struct ads1x1x_data *data = dev->data;
426 	uint8_t resolution = data->differential ? config->resolution : config->resolution - 1;
427 	int err;
428 
429 	if (sequence->resolution != resolution) {
430 		LOG_ERR("unsupported resolution %d", sequence->resolution);
431 		return -ENOTSUP;
432 	}
433 
434 	if (sequence->channels != BIT(0)) {
435 		LOG_ERR("only channel 0 supported");
436 		return -ENOTSUP;
437 	}
438 
439 	if (sequence->oversampling) {
440 		LOG_ERR("oversampling not supported");
441 		return -ENOTSUP;
442 	}
443 
444 	err = ads1x1x_validate_buffer_size(sequence);
445 	if (err) {
446 		LOG_ERR("buffer size too small");
447 		return -ENOTSUP;
448 	}
449 
450 	return 0;
451 }
452 
adc_context_update_buffer_pointer(struct adc_context * ctx,bool repeat_sampling)453 static void adc_context_update_buffer_pointer(struct adc_context *ctx, bool repeat_sampling)
454 {
455 	struct ads1x1x_data *data = CONTAINER_OF(ctx, struct ads1x1x_data, ctx);
456 
457 	if (repeat_sampling) {
458 		data->buffer = data->repeat_buffer;
459 	}
460 }
461 
adc_context_start_sampling(struct adc_context * ctx)462 static void adc_context_start_sampling(struct adc_context *ctx)
463 {
464 	struct ads1x1x_data *data = CONTAINER_OF(ctx, struct ads1x1x_data, ctx);
465 	int ret;
466 
467 	data->repeat_buffer = data->buffer;
468 
469 	ret = ads1x1x_start_conversion(data->dev);
470 	if (ret != 0) {
471 		/* if we fail to complete the I2C operations to start
472 		 * sampling, return an immediate error (likely -EIO) rather
473 		 * than handing it off to the acquisition thread.
474 		 */
475 		adc_context_complete(ctx, ret);
476 		return;
477 	}
478 	k_sem_give(&data->acq_sem);
479 }
480 
ads1x1x_adc_start_read(const struct device * dev,const struct adc_sequence * sequence)481 static int ads1x1x_adc_start_read(const struct device *dev, const struct adc_sequence *sequence)
482 {
483 	int rc;
484 	struct ads1x1x_data *data = dev->data;
485 
486 	rc = ads1x1x_validate_sequence(dev, sequence);
487 	if (rc != 0) {
488 		return rc;
489 	}
490 
491 	data->buffer = sequence->buffer;
492 
493 	adc_context_start_read(&data->ctx, sequence);
494 
495 	return adc_context_wait_for_completion(&data->ctx);
496 }
497 
ads1x1x_adc_read_async(const struct device * dev,const struct adc_sequence * sequence,struct k_poll_signal * async)498 static int ads1x1x_adc_read_async(const struct device *dev, const struct adc_sequence *sequence,
499 				  struct k_poll_signal *async)
500 {
501 	int rc;
502 	struct ads1x1x_data *data = dev->data;
503 
504 	adc_context_lock(&data->ctx, async ? true : false, async);
505 	rc = ads1x1x_adc_start_read(dev, sequence);
506 	adc_context_release(&data->ctx, rc);
507 
508 	return rc;
509 }
510 
ads1x1x_adc_perform_read(const struct device * dev)511 static int ads1x1x_adc_perform_read(const struct device *dev)
512 {
513 	int rc;
514 	struct ads1x1x_data *data = dev->data;
515 	const struct ads1x1x_config *config = dev->config;
516 	int16_t buf;
517 
518 	rc = ads1x1x_read_reg(dev, ADS1X1X_REG_CONV, &buf);
519 	if (rc != 0) {
520 		adc_context_complete(&data->ctx, rc);
521 		return rc;
522 	}
523 	/* The ads101x stores it's 12b data in the upper part
524 	 * while the ads111x uses all 16b in the register, so
525 	 * shift down. Data is also signed, so perform
526 	 * division rather than shifting
527 	 */
528 	*data->buffer++ = buf / (1 << (16 - config->resolution));
529 
530 	adc_context_on_sampling_done(&data->ctx, dev);
531 
532 	return rc;
533 }
534 
ads1x1x_read(const struct device * dev,const struct adc_sequence * sequence)535 static int ads1x1x_read(const struct device *dev, const struct adc_sequence *sequence)
536 {
537 	return ads1x1x_adc_read_async(dev, sequence, NULL);
538 }
539 
ads1x1x_acquisition_thread(const struct device * dev)540 static void ads1x1x_acquisition_thread(const struct device *dev)
541 {
542 	struct ads1x1x_data *data = dev->data;
543 	int rc;
544 
545 	while (true) {
546 		k_sem_take(&data->acq_sem, K_FOREVER);
547 
548 		rc = ads1x1x_wait_data_ready(dev);
549 		if (rc != 0) {
550 			LOG_ERR("failed to get ready status (err %d)", rc);
551 			adc_context_complete(&data->ctx, rc);
552 			continue;
553 		}
554 
555 		ads1x1x_adc_perform_read(dev);
556 	}
557 }
558 
ads1x1x_init(const struct device * dev)559 static int ads1x1x_init(const struct device *dev)
560 {
561 	const struct ads1x1x_config *config = dev->config;
562 	struct ads1x1x_data *data = dev->data;
563 
564 	data->dev = dev;
565 
566 	k_sem_init(&data->acq_sem, 0, 1);
567 
568 	if (!device_is_ready(config->bus.bus)) {
569 		LOG_ERR("I2C bus %s not ready", config->bus.bus->name);
570 		return -ENODEV;
571 	}
572 
573 	const k_tid_t tid =
574 		k_thread_create(&data->thread, data->stack, K_THREAD_STACK_SIZEOF(data->stack),
575 				(k_thread_entry_t)ads1x1x_acquisition_thread, (void *)dev, NULL,
576 				NULL, CONFIG_ADC_ADS1X1X_ACQUISITION_THREAD_PRIO, 0, K_NO_WAIT);
577 	k_thread_name_set(tid, "adc_ads1x1x");
578 
579 	adc_context_unlock_unconditionally(&data->ctx);
580 
581 	return 0;
582 }
583 
584 static const struct adc_driver_api ads1x1x_api = {
585 	.channel_setup = ads1x1x_channel_setup,
586 	.read = ads1x1x_read,
587 	.ref_internal = 2048,
588 #ifdef CONFIG_ADC_ASYNC
589 	.read_async = ads1x1x_adc_read_async,
590 #endif
591 };
592 
593 #define DT_INST_ADS1X1X(inst, t) DT_INST(inst, ti_ads##t)
594 
595 #define ADS1X1X_INIT(t, n, odr_delay_us, res, mux, pgab)                                           \
596 	static const struct ads1x1x_config ads##t##_config_##n = {                                 \
597 		.bus = I2C_DT_SPEC_GET(DT_INST_ADS1X1X(n, t)),                                     \
598 		.odr_delay = odr_delay_us,                                                         \
599 		.resolution = res,                                                                 \
600 		.multiplexer = mux,                                                                \
601 		.pga = pgab,                                                                       \
602 	};                                                                                         \
603 	static struct ads1x1x_data ads##t##_data_##n = {                                           \
604 		ADC_CONTEXT_INIT_LOCK(ads##t##_data_##n, ctx),                                     \
605 		ADC_CONTEXT_INIT_TIMER(ads##t##_data_##n, ctx),                                    \
606 		ADC_CONTEXT_INIT_SYNC(ads##t##_data_##n, ctx),                                     \
607 	};                                                                                         \
608 	DEVICE_DT_DEFINE(DT_INST_ADS1X1X(n, t), ads1x1x_init, NULL, &ads##t##_data_##n,            \
609 			 &ads##t##_config_##n, POST_KERNEL, CONFIG_ADC_ADS1X1X_INIT_PRIORITY,      \
610 			 &ads1x1x_api);
611 
612 /* The ADS111X provides 16 bits of data in binary two's complement format
613  * A positive full-scale (+FS) input produces an output code of 7FFFh and a
614  * negative full-scale (–FS) input produces an output code of 8000h. Single
615  * ended signal measurements only only use the positive code range from
616  * 0000h to 7FFFh
617  */
618 #define ADS111X_RESOLUTION 16
619 
620 /*
621  * Approximated ADS111x acquisition times in microseconds. These are
622  * used for the initial delay when polling for data ready.
623  * {8 SPS, 16 SPS, 32 SPS, 64 SPS, 128 SPS (default), 250 SPS, 475 SPS, 860 SPS}
624  */
625 #define ADS111X_ODR_DELAY_US                                                                       \
626 	{                                                                                          \
627 		125000, 62500, 31250, 15625, 7813, 4000, 2105, 1163                                \
628 	}
629 
630 /*
631  * ADS1115: 16 bit, multiplexer, programmable gain amplifier
632  */
633 #define ADS1115_INIT(n) ADS1X1X_INIT(1115, n, ADS111X_ODR_DELAY_US, ADS111X_RESOLUTION, true, true)
634 #undef DT_DRV_COMPAT
635 #define DT_DRV_COMPAT ti_ads1115
636 DT_INST_FOREACH_STATUS_OKAY(ADS1115_INIT)
637 
638 /*
639  * ADS1114: 16 bit, no multiplexer, programmable gain amplifier
640  */
641 #define ADS1114_INIT(n) ADS1X1X_INIT(1114, n, ADS111X_ODR_DELAY_US, ADS111X_RESOLUTION, false, true)
642 #undef DT_DRV_COMPAT
643 #define DT_DRV_COMPAT ti_ads1114
644 DT_INST_FOREACH_STATUS_OKAY(ADS1114_INIT)
645 
646 /*
647  * ADS1113: 16 bit, no multiplexer, no programmable gain amplifier
648  */
649 #define ADS1113_INIT(n)                                                                            \
650 	ADS1X1X_INIT(1113, n, ADS111X_ODR_DELAY_US, ADS111X_RESOLUTION, false, false)
651 #undef DT_DRV_COMPAT
652 #define DT_DRV_COMPAT ti_ads1113
653 DT_INST_FOREACH_STATUS_OKAY(ADS1113_INIT)
654 
655 /* The ADS101X provides 12 bits of data in binary two's complement format
656  * A positive full-scale (+FS) input produces an output code of 7FFh and a
657  * negative full-scale (–FS) input produces an output code of 800h. Single
658  * ended signal measurements only only use the positive code range from
659  * 000h to 7FFh
660  */
661 #define ADS101X_RESOLUTION 12
662 
663 /*
664  * Approximated ADS101x acquisition times in microseconds. These are
665  * used for the initial delay when polling for data ready.
666  * {128 SPS, 250 SPS, 490 SPS, 920 SPS, 1600 SPS (default), 2400 SPS, 3300 SPS, 3300 SPS}
667  */
668 #define ADS101X_ODR_DELAY_US                                                                       \
669 	{                                                                                          \
670 		7813, 4000, 2041, 1087, 625, 417, 303, 303                                         \
671 	}
672 
673 /*
674  * ADS1015: 12 bit, multiplexer, programmable gain amplifier
675  */
676 #define ADS1015_INIT(n) ADS1X1X_INIT(1015, n, ADS101X_ODR_DELAY_US, ADS101X_RESOLUTION, true, true)
677 #undef DT_DRV_COMPAT
678 #define DT_DRV_COMPAT ti_ads1015
679 DT_INST_FOREACH_STATUS_OKAY(ADS1015_INIT)
680 
681 /*
682  * ADS1014: 12 bit, no multiplexer, programmable gain amplifier
683  */
684 #define ADS1014_INIT(n) ADS1X1X_INIT(1014, n, ADS101X_ODR_DELAY_US, ADS101X_RESOLUTION, false, true)
685 #undef DT_DRV_COMPAT
686 #define DT_DRV_COMPAT ti_ads1014
687 DT_INST_FOREACH_STATUS_OKAY(ADS1014_INIT)
688 
689 /*
690  * ADS1013: 12 bit, no multiplexer, no programmable gain amplifier
691  */
692 #define ADS1013_INIT(n)                                                                            \
693 	ADS1X1X_INIT(1013, n, ADS101X_ODR_DELAY_US, ADS101X_RESOLUTION, false, false)
694 #undef DT_DRV_COMPAT
695 #define DT_DRV_COMPAT ti_ads1013
696 DT_INST_FOREACH_STATUS_OKAY(ADS1013_INIT)
697