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9#include <linux/device.h>
10#include <linux/err.h>
11#include <linux/i2c.h>
12#include <linux/interrupt.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/mutex.h>
16#include <linux/regulator/consumer.h>
17#include <linux/slab.h>
18#include <linux/sysfs.h>
19
20#include <linux/iio/iio.h>
21#include <linux/iio/sysfs.h>
22#include <linux/iio/events.h>
23
24#include <linux/platform_data/ad7291.h>
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39#define AD7291_COMMAND 0x00
40#define AD7291_VOLTAGE 0x01
41#define AD7291_T_SENSE 0x02
42#define AD7291_T_AVERAGE 0x03
43#define AD7291_DATA_HIGH(x) ((x) * 3 + 0x4)
44#define AD7291_DATA_LOW(x) ((x) * 3 + 0x5)
45#define AD7291_HYST(x) ((x) * 3 + 0x6)
46#define AD7291_VOLTAGE_ALERT_STATUS 0x1F
47#define AD7291_T_ALERT_STATUS 0x20
48
49#define AD7291_BITS 12
50#define AD7291_VOLTAGE_LIMIT_COUNT 8
51
52
53
54
55
56#define AD7291_AUTOCYCLE BIT(0)
57#define AD7291_RESET BIT(1)
58#define AD7291_ALERT_CLEAR BIT(2)
59#define AD7291_ALERT_POLARITY BIT(3)
60#define AD7291_EXT_REF BIT(4)
61#define AD7291_NOISE_DELAY BIT(5)
62#define AD7291_T_SENSE_MASK BIT(7)
63#define AD7291_VOLTAGE_MASK GENMASK(15, 8)
64#define AD7291_VOLTAGE_OFFSET 8
65
66
67
68
69#define AD7291_VALUE_MASK GENMASK(11, 0)
70
71
72
73
74#define AD7291_T_LOW BIT(0)
75#define AD7291_T_HIGH BIT(1)
76#define AD7291_T_AVG_LOW BIT(2)
77#define AD7291_T_AVG_HIGH BIT(3)
78#define AD7291_V_LOW(x) BIT((x) * 2)
79#define AD7291_V_HIGH(x) BIT((x) * 2 + 1)
80
81
82struct ad7291_chip_info {
83 struct i2c_client *client;
84 struct regulator *reg;
85 u16 command;
86 u16 c_mask;
87 struct mutex state_lock;
88};
89
90static int ad7291_i2c_read(struct ad7291_chip_info *chip, u8 reg, u16 *data)
91{
92 struct i2c_client *client = chip->client;
93 int ret = 0;
94
95 ret = i2c_smbus_read_word_swapped(client, reg);
96 if (ret < 0) {
97 dev_err(&client->dev, "I2C read error\n");
98 return ret;
99 }
100
101 *data = ret;
102
103 return 0;
104}
105
106static int ad7291_i2c_write(struct ad7291_chip_info *chip, u8 reg, u16 data)
107{
108 return i2c_smbus_write_word_swapped(chip->client, reg, data);
109}
110
111static irqreturn_t ad7291_event_handler(int irq, void *private)
112{
113 struct iio_dev *indio_dev = private;
114 struct ad7291_chip_info *chip = iio_priv(private);
115 u16 t_status, v_status;
116 u16 command;
117 int i;
118 s64 timestamp = iio_get_time_ns(indio_dev);
119
120 if (ad7291_i2c_read(chip, AD7291_T_ALERT_STATUS, &t_status))
121 return IRQ_HANDLED;
122
123 if (ad7291_i2c_read(chip, AD7291_VOLTAGE_ALERT_STATUS, &v_status))
124 return IRQ_HANDLED;
125
126 if (!(t_status || v_status))
127 return IRQ_HANDLED;
128
129 command = chip->command | AD7291_ALERT_CLEAR;
130 ad7291_i2c_write(chip, AD7291_COMMAND, command);
131
132 command = chip->command & ~AD7291_ALERT_CLEAR;
133 ad7291_i2c_write(chip, AD7291_COMMAND, command);
134
135
136 if ((t_status & AD7291_T_LOW) || (t_status & AD7291_T_AVG_LOW))
137 iio_push_event(indio_dev,
138 IIO_UNMOD_EVENT_CODE(IIO_TEMP,
139 0,
140 IIO_EV_TYPE_THRESH,
141 IIO_EV_DIR_FALLING),
142 timestamp);
143 if ((t_status & AD7291_T_HIGH) || (t_status & AD7291_T_AVG_HIGH))
144 iio_push_event(indio_dev,
145 IIO_UNMOD_EVENT_CODE(IIO_TEMP,
146 0,
147 IIO_EV_TYPE_THRESH,
148 IIO_EV_DIR_RISING),
149 timestamp);
150
151 for (i = 0; i < AD7291_VOLTAGE_LIMIT_COUNT; i++) {
152 if (v_status & AD7291_V_LOW(i))
153 iio_push_event(indio_dev,
154 IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
155 i,
156 IIO_EV_TYPE_THRESH,
157 IIO_EV_DIR_FALLING),
158 timestamp);
159 if (v_status & AD7291_V_HIGH(i))
160 iio_push_event(indio_dev,
161 IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
162 i,
163 IIO_EV_TYPE_THRESH,
164 IIO_EV_DIR_RISING),
165 timestamp);
166 }
167
168 return IRQ_HANDLED;
169}
170
171static unsigned int ad7291_threshold_reg(const struct iio_chan_spec *chan,
172 enum iio_event_direction dir,
173 enum iio_event_info info)
174{
175 unsigned int offset;
176
177 switch (chan->type) {
178 case IIO_VOLTAGE:
179 offset = chan->channel;
180 break;
181 case IIO_TEMP:
182 offset = AD7291_VOLTAGE_OFFSET;
183 break;
184 default:
185 return 0;
186 }
187
188 switch (info) {
189 case IIO_EV_INFO_VALUE:
190 if (dir == IIO_EV_DIR_FALLING)
191 return AD7291_DATA_HIGH(offset);
192 else
193 return AD7291_DATA_LOW(offset);
194 case IIO_EV_INFO_HYSTERESIS:
195 return AD7291_HYST(offset);
196 default:
197 break;
198 }
199 return 0;
200}
201
202static int ad7291_read_event_value(struct iio_dev *indio_dev,
203 const struct iio_chan_spec *chan,
204 enum iio_event_type type,
205 enum iio_event_direction dir,
206 enum iio_event_info info,
207 int *val, int *val2)
208{
209 struct ad7291_chip_info *chip = iio_priv(indio_dev);
210 int ret;
211 u16 uval;
212
213 ret = ad7291_i2c_read(chip, ad7291_threshold_reg(chan, dir, info),
214 &uval);
215 if (ret < 0)
216 return ret;
217
218 if (info == IIO_EV_INFO_HYSTERESIS || chan->type == IIO_VOLTAGE)
219 *val = uval & AD7291_VALUE_MASK;
220
221 else
222 *val = sign_extend32(uval, 11);
223
224 return IIO_VAL_INT;
225}
226
227static int ad7291_write_event_value(struct iio_dev *indio_dev,
228 const struct iio_chan_spec *chan,
229 enum iio_event_type type,
230 enum iio_event_direction dir,
231 enum iio_event_info info,
232 int val, int val2)
233{
234 struct ad7291_chip_info *chip = iio_priv(indio_dev);
235
236 if (info == IIO_EV_INFO_HYSTERESIS || chan->type == IIO_VOLTAGE) {
237 if (val > AD7291_VALUE_MASK || val < 0)
238 return -EINVAL;
239 } else {
240 if (val > 2047 || val < -2048)
241 return -EINVAL;
242 }
243
244 return ad7291_i2c_write(chip, ad7291_threshold_reg(chan, dir, info),
245 val);
246}
247
248static int ad7291_read_event_config(struct iio_dev *indio_dev,
249 const struct iio_chan_spec *chan,
250 enum iio_event_type type,
251 enum iio_event_direction dir)
252{
253 struct ad7291_chip_info *chip = iio_priv(indio_dev);
254
255
256
257
258
259 switch (chan->type) {
260 case IIO_VOLTAGE:
261 return !!(chip->c_mask & BIT(15 - chan->channel));
262 case IIO_TEMP:
263
264 return 1;
265 default:
266 return -EINVAL;
267 }
268
269}
270
271static int ad7291_write_event_config(struct iio_dev *indio_dev,
272 const struct iio_chan_spec *chan,
273 enum iio_event_type type,
274 enum iio_event_direction dir,
275 int state)
276{
277 int ret = 0;
278 struct ad7291_chip_info *chip = iio_priv(indio_dev);
279 unsigned int mask;
280 u16 regval;
281
282 mutex_lock(&chip->state_lock);
283 regval = chip->command;
284
285
286
287
288
289
290 mask = BIT(15 - chan->channel);
291
292 switch (chan->type) {
293 case IIO_VOLTAGE:
294 if ((!state) && (chip->c_mask & mask))
295 chip->c_mask &= ~mask;
296 else if (state && (!(chip->c_mask & mask)))
297 chip->c_mask |= mask;
298 else
299 break;
300
301 regval &= ~AD7291_AUTOCYCLE;
302 regval |= chip->c_mask;
303 if (chip->c_mask)
304 regval |= AD7291_AUTOCYCLE;
305
306 ret = ad7291_i2c_write(chip, AD7291_COMMAND, regval);
307 if (ret < 0)
308 goto error_ret;
309
310 chip->command = regval;
311 break;
312 default:
313 ret = -EINVAL;
314 }
315
316error_ret:
317 mutex_unlock(&chip->state_lock);
318 return ret;
319}
320
321static int ad7291_read_raw(struct iio_dev *indio_dev,
322 struct iio_chan_spec const *chan,
323 int *val,
324 int *val2,
325 long mask)
326{
327 int ret;
328 struct ad7291_chip_info *chip = iio_priv(indio_dev);
329 u16 regval;
330
331 switch (mask) {
332 case IIO_CHAN_INFO_RAW:
333 switch (chan->type) {
334 case IIO_VOLTAGE:
335 mutex_lock(&chip->state_lock);
336
337 if (chip->command & AD7291_AUTOCYCLE) {
338 mutex_unlock(&chip->state_lock);
339 return -EBUSY;
340 }
341
342 regval = chip->command & (~AD7291_VOLTAGE_MASK);
343 regval |= BIT(15 - chan->channel);
344 ret = ad7291_i2c_write(chip, AD7291_COMMAND, regval);
345 if (ret < 0) {
346 mutex_unlock(&chip->state_lock);
347 return ret;
348 }
349
350 ret = i2c_smbus_read_word_swapped(chip->client,
351 AD7291_VOLTAGE);
352 if (ret < 0) {
353 mutex_unlock(&chip->state_lock);
354 return ret;
355 }
356 *val = ret & AD7291_VALUE_MASK;
357 mutex_unlock(&chip->state_lock);
358 return IIO_VAL_INT;
359 case IIO_TEMP:
360
361 ret = i2c_smbus_read_word_swapped(chip->client,
362 AD7291_T_SENSE);
363 if (ret < 0)
364 return ret;
365 *val = sign_extend32(ret, 11);
366 return IIO_VAL_INT;
367 default:
368 return -EINVAL;
369 }
370 case IIO_CHAN_INFO_AVERAGE_RAW:
371 ret = i2c_smbus_read_word_swapped(chip->client,
372 AD7291_T_AVERAGE);
373 if (ret < 0)
374 return ret;
375 *val = sign_extend32(ret, 11);
376 return IIO_VAL_INT;
377 case IIO_CHAN_INFO_SCALE:
378 switch (chan->type) {
379 case IIO_VOLTAGE:
380 if (chip->reg) {
381 int vref;
382
383 vref = regulator_get_voltage(chip->reg);
384 if (vref < 0)
385 return vref;
386 *val = vref / 1000;
387 } else {
388 *val = 2500;
389 }
390 *val2 = AD7291_BITS;
391 return IIO_VAL_FRACTIONAL_LOG2;
392 case IIO_TEMP:
393
394
395
396
397
398 *val = 250;
399 return IIO_VAL_INT;
400 default:
401 return -EINVAL;
402 }
403 default:
404 return -EINVAL;
405 }
406}
407
408static const struct iio_event_spec ad7291_events[] = {
409 {
410 .type = IIO_EV_TYPE_THRESH,
411 .dir = IIO_EV_DIR_RISING,
412 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
413 BIT(IIO_EV_INFO_ENABLE),
414 }, {
415 .type = IIO_EV_TYPE_THRESH,
416 .dir = IIO_EV_DIR_FALLING,
417 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
418 BIT(IIO_EV_INFO_ENABLE),
419 }, {
420 .type = IIO_EV_TYPE_THRESH,
421 .dir = IIO_EV_DIR_EITHER,
422 .mask_separate = BIT(IIO_EV_INFO_HYSTERESIS),
423 },
424};
425
426#define AD7291_VOLTAGE_CHAN(_chan) \
427{ \
428 .type = IIO_VOLTAGE, \
429 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
430 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
431 .indexed = 1, \
432 .channel = _chan, \
433 .event_spec = ad7291_events, \
434 .num_event_specs = ARRAY_SIZE(ad7291_events), \
435}
436
437static const struct iio_chan_spec ad7291_channels[] = {
438 AD7291_VOLTAGE_CHAN(0),
439 AD7291_VOLTAGE_CHAN(1),
440 AD7291_VOLTAGE_CHAN(2),
441 AD7291_VOLTAGE_CHAN(3),
442 AD7291_VOLTAGE_CHAN(4),
443 AD7291_VOLTAGE_CHAN(5),
444 AD7291_VOLTAGE_CHAN(6),
445 AD7291_VOLTAGE_CHAN(7),
446 {
447 .type = IIO_TEMP,
448 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
449 BIT(IIO_CHAN_INFO_AVERAGE_RAW) |
450 BIT(IIO_CHAN_INFO_SCALE),
451 .indexed = 1,
452 .channel = 0,
453 .event_spec = ad7291_events,
454 .num_event_specs = ARRAY_SIZE(ad7291_events),
455 }
456};
457
458static const struct iio_info ad7291_info = {
459 .read_raw = &ad7291_read_raw,
460 .read_event_config = &ad7291_read_event_config,
461 .write_event_config = &ad7291_write_event_config,
462 .read_event_value = &ad7291_read_event_value,
463 .write_event_value = &ad7291_write_event_value,
464};
465
466static int ad7291_probe(struct i2c_client *client,
467 const struct i2c_device_id *id)
468{
469 struct ad7291_platform_data *pdata = client->dev.platform_data;
470 struct ad7291_chip_info *chip;
471 struct iio_dev *indio_dev;
472 int ret;
473
474 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
475 if (!indio_dev)
476 return -ENOMEM;
477 chip = iio_priv(indio_dev);
478
479 if (pdata && pdata->use_external_ref) {
480 chip->reg = devm_regulator_get(&client->dev, "vref");
481 if (IS_ERR(chip->reg))
482 return PTR_ERR(chip->reg);
483
484 ret = regulator_enable(chip->reg);
485 if (ret)
486 return ret;
487 }
488
489 mutex_init(&chip->state_lock);
490
491 i2c_set_clientdata(client, indio_dev);
492
493 chip->client = client;
494
495 chip->command = AD7291_NOISE_DELAY |
496 AD7291_T_SENSE_MASK |
497 AD7291_ALERT_POLARITY;
498
499 if (pdata && pdata->use_external_ref)
500 chip->command |= AD7291_EXT_REF;
501
502 indio_dev->name = id->name;
503 indio_dev->channels = ad7291_channels;
504 indio_dev->num_channels = ARRAY_SIZE(ad7291_channels);
505
506 indio_dev->dev.parent = &client->dev;
507 indio_dev->dev.of_node = client->dev.of_node;
508 indio_dev->info = &ad7291_info;
509 indio_dev->modes = INDIO_DIRECT_MODE;
510
511 ret = ad7291_i2c_write(chip, AD7291_COMMAND, AD7291_RESET);
512 if (ret) {
513 ret = -EIO;
514 goto error_disable_reg;
515 }
516
517 ret = ad7291_i2c_write(chip, AD7291_COMMAND, chip->command);
518 if (ret) {
519 ret = -EIO;
520 goto error_disable_reg;
521 }
522
523 if (client->irq > 0) {
524 ret = request_threaded_irq(client->irq,
525 NULL,
526 &ad7291_event_handler,
527 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
528 id->name,
529 indio_dev);
530 if (ret)
531 goto error_disable_reg;
532 }
533
534 ret = iio_device_register(indio_dev);
535 if (ret)
536 goto error_unreg_irq;
537
538 return 0;
539
540error_unreg_irq:
541 if (client->irq)
542 free_irq(client->irq, indio_dev);
543error_disable_reg:
544 if (chip->reg)
545 regulator_disable(chip->reg);
546
547 return ret;
548}
549
550static int ad7291_remove(struct i2c_client *client)
551{
552 struct iio_dev *indio_dev = i2c_get_clientdata(client);
553 struct ad7291_chip_info *chip = iio_priv(indio_dev);
554
555 iio_device_unregister(indio_dev);
556
557 if (client->irq)
558 free_irq(client->irq, indio_dev);
559
560 if (chip->reg)
561 regulator_disable(chip->reg);
562
563 return 0;
564}
565
566static const struct i2c_device_id ad7291_id[] = {
567 { "ad7291", 0 },
568 {}
569};
570
571MODULE_DEVICE_TABLE(i2c, ad7291_id);
572
573static struct i2c_driver ad7291_driver = {
574 .driver = {
575 .name = KBUILD_MODNAME,
576 },
577 .probe = ad7291_probe,
578 .remove = ad7291_remove,
579 .id_table = ad7291_id,
580};
581module_i2c_driver(ad7291_driver);
582
583MODULE_AUTHOR("Sonic Zhang <sonic.zhang@analog.com>");
584MODULE_DESCRIPTION("Analog Devices AD7291 ADC driver");
585MODULE_LICENSE("GPL v2");
586
