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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * AD7291 8-Channel, I2C, 12-Bit SAR ADC with Temperature Sensor
4 *
5 * Copyright 2010-2011 Analog Devices Inc.
6 */
7
8#include <linux/device.h>
9#include <linux/err.h>
10#include <linux/i2c.h>
11#include <linux/interrupt.h>
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/mutex.h>
15#include <linux/regulator/consumer.h>
16#include <linux/slab.h>
17#include <linux/sysfs.h>
18
19#include <linux/iio/iio.h>
20#include <linux/iio/sysfs.h>
21#include <linux/iio/events.h>
22
23#include <linux/platform_data/ad7291.h>
24
25/*
26 * Simplified handling
27 *
28 * If no events enabled - single polled channel read
29 * If event enabled direct reads disable unless channel
30 * is in the read mask.
31 *
32 * The noise-delayed bit as per datasheet suggestion is always enabled.
33 */
34
35/*
36 * AD7291 registers definition
37 */
38#define AD7291_COMMAND 0x00
39#define AD7291_VOLTAGE 0x01
40#define AD7291_T_SENSE 0x02
41#define AD7291_T_AVERAGE 0x03
42#define AD7291_DATA_HIGH(x) ((x) * 3 + 0x4)
43#define AD7291_DATA_LOW(x) ((x) * 3 + 0x5)
44#define AD7291_HYST(x) ((x) * 3 + 0x6)
45#define AD7291_VOLTAGE_ALERT_STATUS 0x1F
46#define AD7291_T_ALERT_STATUS 0x20
47
48#define AD7291_BITS 12
49#define AD7291_VOLTAGE_LIMIT_COUNT 8
50
51
52/*
53 * AD7291 command
54 */
55#define AD7291_AUTOCYCLE BIT(0)
56#define AD7291_RESET BIT(1)
57#define AD7291_ALERT_CLEAR BIT(2)
58#define AD7291_ALERT_POLARITY BIT(3)
59#define AD7291_EXT_REF BIT(4)
60#define AD7291_NOISE_DELAY BIT(5)
61#define AD7291_T_SENSE_MASK BIT(7)
62#define AD7291_VOLTAGE_MASK GENMASK(15, 8)
63#define AD7291_VOLTAGE_OFFSET 8
64
65/*
66 * AD7291 value masks
67 */
68#define AD7291_VALUE_MASK GENMASK(11, 0)
69
70/*
71 * AD7291 alert register bits
72 */
73#define AD7291_T_LOW BIT(0)
74#define AD7291_T_HIGH BIT(1)
75#define AD7291_T_AVG_LOW BIT(2)
76#define AD7291_T_AVG_HIGH BIT(3)
77#define AD7291_V_LOW(x) BIT((x) * 2)
78#define AD7291_V_HIGH(x) BIT((x) * 2 + 1)
79
80
81struct ad7291_chip_info {
82 struct i2c_client *client;
83 struct regulator *reg;
84 u16 command;
85 u16 c_mask; /* Active voltage channels for events */
86 struct mutex state_lock;
87};
88
89static int ad7291_i2c_read(struct ad7291_chip_info *chip, u8 reg, u16 *data)
90{
91 struct i2c_client *client = chip->client;
92 int ret = 0;
93
94 ret = i2c_smbus_read_word_swapped(client, reg);
95 if (ret < 0) {
96 dev_err(&client->dev, "I2C read error\n");
97 return ret;
98 }
99
100 *data = ret;
101
102 return 0;
103}
104
105static int ad7291_i2c_write(struct ad7291_chip_info *chip, u8 reg, u16 data)
106{
107 return i2c_smbus_write_word_swapped(chip->client, reg, data);
108}
109
110static irqreturn_t ad7291_event_handler(int irq, void *private)
111{
112 struct iio_dev *indio_dev = private;
113 struct ad7291_chip_info *chip = iio_priv(private);
114 u16 t_status, v_status;
115 u16 command;
116 int i;
117 s64 timestamp = iio_get_time_ns(indio_dev);
118
119 if (ad7291_i2c_read(chip, AD7291_T_ALERT_STATUS, &t_status))
120 return IRQ_HANDLED;
121
122 if (ad7291_i2c_read(chip, AD7291_VOLTAGE_ALERT_STATUS, &v_status))
123 return IRQ_HANDLED;
124
125 if (!(t_status || v_status))
126 return IRQ_HANDLED;
127
128 command = chip->command | AD7291_ALERT_CLEAR;
129 ad7291_i2c_write(chip, AD7291_COMMAND, command);
130
131 command = chip->command & ~AD7291_ALERT_CLEAR;
132 ad7291_i2c_write(chip, AD7291_COMMAND, command);
133
134 /* For now treat t_sense and t_sense_average the same */
135 if ((t_status & AD7291_T_LOW) || (t_status & AD7291_T_AVG_LOW))
136 iio_push_event(indio_dev,
137 IIO_UNMOD_EVENT_CODE(IIO_TEMP,
138 0,
139 IIO_EV_TYPE_THRESH,
140 IIO_EV_DIR_FALLING),
141 timestamp);
142 if ((t_status & AD7291_T_HIGH) || (t_status & AD7291_T_AVG_HIGH))
143 iio_push_event(indio_dev,
144 IIO_UNMOD_EVENT_CODE(IIO_TEMP,
145 0,
146 IIO_EV_TYPE_THRESH,
147 IIO_EV_DIR_RISING),
148 timestamp);
149
150 for (i = 0; i < AD7291_VOLTAGE_LIMIT_COUNT; i++) {
151 if (v_status & AD7291_V_LOW(i))
152 iio_push_event(indio_dev,
153 IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
154 i,
155 IIO_EV_TYPE_THRESH,
156 IIO_EV_DIR_FALLING),
157 timestamp);
158 if (v_status & AD7291_V_HIGH(i))
159 iio_push_event(indio_dev,
160 IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
161 i,
162 IIO_EV_TYPE_THRESH,
163 IIO_EV_DIR_RISING),
164 timestamp);
165 }
166
167 return IRQ_HANDLED;
168}
169
170static unsigned int ad7291_threshold_reg(const struct iio_chan_spec *chan,
171 enum iio_event_direction dir,
172 enum iio_event_info info)
173{
174 unsigned int offset;
175
176 switch (chan->type) {
177 case IIO_VOLTAGE:
178 offset = chan->channel;
179 break;
180 case IIO_TEMP:
181 offset = AD7291_VOLTAGE_OFFSET;
182 break;
183 default:
184 return 0;
185 }
186
187 switch (info) {
188 case IIO_EV_INFO_VALUE:
189 if (dir == IIO_EV_DIR_FALLING)
190 return AD7291_DATA_HIGH(offset);
191 else
192 return AD7291_DATA_LOW(offset);
193 case IIO_EV_INFO_HYSTERESIS:
194 return AD7291_HYST(offset);
195 default:
196 break;
197 }
198 return 0;
199}
200
201static int ad7291_read_event_value(struct iio_dev *indio_dev,
202 const struct iio_chan_spec *chan,
203 enum iio_event_type type,
204 enum iio_event_direction dir,
205 enum iio_event_info info,
206 int *val, int *val2)
207{
208 struct ad7291_chip_info *chip = iio_priv(indio_dev);
209 int ret;
210 u16 uval;
211
212 ret = ad7291_i2c_read(chip, ad7291_threshold_reg(chan, dir, info),
213 &uval);
214 if (ret < 0)
215 return ret;
216
217 if (info == IIO_EV_INFO_HYSTERESIS || chan->type == IIO_VOLTAGE)
218 *val = uval & AD7291_VALUE_MASK;
219
220 else
221 *val = sign_extend32(uval, 11);
222
223 return IIO_VAL_INT;
224}
225
226static int ad7291_write_event_value(struct iio_dev *indio_dev,
227 const struct iio_chan_spec *chan,
228 enum iio_event_type type,
229 enum iio_event_direction dir,
230 enum iio_event_info info,
231 int val, int val2)
232{
233 struct ad7291_chip_info *chip = iio_priv(indio_dev);
234
235 if (info == IIO_EV_INFO_HYSTERESIS || chan->type == IIO_VOLTAGE) {
236 if (val > AD7291_VALUE_MASK || val < 0)
237 return -EINVAL;
238 } else {
239 if (val > 2047 || val < -2048)
240 return -EINVAL;
241 }
242
243 return ad7291_i2c_write(chip, ad7291_threshold_reg(chan, dir, info),
244 val);
245}
246
247static int ad7291_read_event_config(struct iio_dev *indio_dev,
248 const struct iio_chan_spec *chan,
249 enum iio_event_type type,
250 enum iio_event_direction dir)
251{
252 struct ad7291_chip_info *chip = iio_priv(indio_dev);
253 /*
254 * To be enabled the channel must simply be on. If any are enabled
255 * we are in continuous sampling mode
256 */
257
258 switch (chan->type) {
259 case IIO_VOLTAGE:
260 return !!(chip->c_mask & BIT(15 - chan->channel));
261 case IIO_TEMP:
262 /* always on */
263 return 1;
264 default:
265 return -EINVAL;
266 }
267
268}
269
270static int ad7291_write_event_config(struct iio_dev *indio_dev,
271 const struct iio_chan_spec *chan,
272 enum iio_event_type type,
273 enum iio_event_direction dir,
274 int state)
275{
276 int ret = 0;
277 struct ad7291_chip_info *chip = iio_priv(indio_dev);
278 unsigned int mask;
279 u16 regval;
280
281 mutex_lock(&chip->state_lock);
282 regval = chip->command;
283 /*
284 * To be enabled the channel must simply be on. If any are enabled
285 * use continuous sampling mode.
286 * Possible to disable temp as well but that makes single read tricky.
287 */
288
289 mask = BIT(15 - chan->channel);
290
291 switch (chan->type) {
292 case IIO_VOLTAGE:
293 if ((!state) && (chip->c_mask & mask))
294 chip->c_mask &= ~mask;
295 else if (state && (!(chip->c_mask & mask)))
296 chip->c_mask |= mask;
297 else
298 break;
299
300 regval &= ~AD7291_AUTOCYCLE;
301 regval |= chip->c_mask;
302 if (chip->c_mask) /* Enable autocycle? */
303 regval |= AD7291_AUTOCYCLE;
304
305 ret = ad7291_i2c_write(chip, AD7291_COMMAND, regval);
306 if (ret < 0)
307 goto error_ret;
308
309 chip->command = regval;
310 break;
311 default:
312 ret = -EINVAL;
313 }
314
315error_ret:
316 mutex_unlock(&chip->state_lock);
317 return ret;
318}
319
320static int ad7291_read_raw(struct iio_dev *indio_dev,
321 struct iio_chan_spec const *chan,
322 int *val,
323 int *val2,
324 long mask)
325{
326 int ret;
327 struct ad7291_chip_info *chip = iio_priv(indio_dev);
328 u16 regval;
329
330 switch (mask) {
331 case IIO_CHAN_INFO_RAW:
332 switch (chan->type) {
333 case IIO_VOLTAGE:
334 mutex_lock(&chip->state_lock);
335 /* If in autocycle mode drop through */
336 if (chip->command & AD7291_AUTOCYCLE) {
337 mutex_unlock(&chip->state_lock);
338 return -EBUSY;
339 }
340 /* Enable this channel alone */
341 regval = chip->command & (~AD7291_VOLTAGE_MASK);
342 regval |= BIT(15 - chan->channel);
343 ret = ad7291_i2c_write(chip, AD7291_COMMAND, regval);
344 if (ret < 0) {
345 mutex_unlock(&chip->state_lock);
346 return ret;
347 }
348 /* Read voltage */
349 ret = i2c_smbus_read_word_swapped(chip->client,
350 AD7291_VOLTAGE);
351 if (ret < 0) {
352 mutex_unlock(&chip->state_lock);
353 return ret;
354 }
355 *val = ret & AD7291_VALUE_MASK;
356 mutex_unlock(&chip->state_lock);
357 return IIO_VAL_INT;
358 case IIO_TEMP:
359 /* Assumes tsense bit of command register always set */
360 ret = i2c_smbus_read_word_swapped(chip->client,
361 AD7291_T_SENSE);
362 if (ret < 0)
363 return ret;
364 *val = sign_extend32(ret, 11);
365 return IIO_VAL_INT;
366 default:
367 return -EINVAL;
368 }
369 case IIO_CHAN_INFO_AVERAGE_RAW:
370 ret = i2c_smbus_read_word_swapped(chip->client,
371 AD7291_T_AVERAGE);
372 if (ret < 0)
373 return ret;
374 *val = sign_extend32(ret, 11);
375 return IIO_VAL_INT;
376 case IIO_CHAN_INFO_SCALE:
377 switch (chan->type) {
378 case IIO_VOLTAGE:
379 if (chip->reg) {
380 int vref;
381
382 vref = regulator_get_voltage(chip->reg);
383 if (vref < 0)
384 return vref;
385 *val = vref / 1000;
386 } else {
387 *val = 2500;
388 }
389 *val2 = AD7291_BITS;
390 return IIO_VAL_FRACTIONAL_LOG2;
391 case IIO_TEMP:
392 /*
393 * One LSB of the ADC corresponds to 0.25 deg C.
394 * The temperature reading is in 12-bit twos
395 * complement format
396 */
397 *val = 250;
398 return IIO_VAL_INT;
399 default:
400 return -EINVAL;
401 }
402 default:
403 return -EINVAL;
404 }
405}
406
407static const struct iio_event_spec ad7291_events[] = {
408 {
409 .type = IIO_EV_TYPE_THRESH,
410 .dir = IIO_EV_DIR_RISING,
411 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
412 BIT(IIO_EV_INFO_ENABLE),
413 }, {
414 .type = IIO_EV_TYPE_THRESH,
415 .dir = IIO_EV_DIR_FALLING,
416 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
417 BIT(IIO_EV_INFO_ENABLE),
418 }, {
419 .type = IIO_EV_TYPE_THRESH,
420 .dir = IIO_EV_DIR_EITHER,
421 .mask_separate = BIT(IIO_EV_INFO_HYSTERESIS),
422 },
423};
424
425#define AD7291_VOLTAGE_CHAN(_chan) \
426{ \
427 .type = IIO_VOLTAGE, \
428 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
429 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
430 .indexed = 1, \
431 .channel = _chan, \
432 .event_spec = ad7291_events, \
433 .num_event_specs = ARRAY_SIZE(ad7291_events), \
434}
435
436static const struct iio_chan_spec ad7291_channels[] = {
437 AD7291_VOLTAGE_CHAN(0),
438 AD7291_VOLTAGE_CHAN(1),
439 AD7291_VOLTAGE_CHAN(2),
440 AD7291_VOLTAGE_CHAN(3),
441 AD7291_VOLTAGE_CHAN(4),
442 AD7291_VOLTAGE_CHAN(5),
443 AD7291_VOLTAGE_CHAN(6),
444 AD7291_VOLTAGE_CHAN(7),
445 {
446 .type = IIO_TEMP,
447 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
448 BIT(IIO_CHAN_INFO_AVERAGE_RAW) |
449 BIT(IIO_CHAN_INFO_SCALE),
450 .indexed = 1,
451 .channel = 0,
452 .event_spec = ad7291_events,
453 .num_event_specs = ARRAY_SIZE(ad7291_events),
454 }
455};
456
457static const struct iio_info ad7291_info = {
458 .read_raw = &ad7291_read_raw,
459 .read_event_config = &ad7291_read_event_config,
460 .write_event_config = &ad7291_write_event_config,
461 .read_event_value = &ad7291_read_event_value,
462 .write_event_value = &ad7291_write_event_value,
463};
464
465static int ad7291_probe(struct i2c_client *client,
466 const struct i2c_device_id *id)
467{
468 struct ad7291_platform_data *pdata = client->dev.platform_data;
469 struct ad7291_chip_info *chip;
470 struct iio_dev *indio_dev;
471 int ret;
472
473 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
474 if (!indio_dev)
475 return -ENOMEM;
476 chip = iio_priv(indio_dev);
477
478 if (pdata && pdata->use_external_ref) {
479 chip->reg = devm_regulator_get(&client->dev, "vref");
480 if (IS_ERR(chip->reg))
481 return PTR_ERR(chip->reg);
482
483 ret = regulator_enable(chip->reg);
484 if (ret)
485 return ret;
486 }
487
488 mutex_init(&chip->state_lock);
489 /* this is only used for device removal purposes */
490 i2c_set_clientdata(client, indio_dev);
491
492 chip->client = client;
493
494 chip->command = AD7291_NOISE_DELAY |
495 AD7291_T_SENSE_MASK | /* Tsense always enabled */
496 AD7291_ALERT_POLARITY; /* set irq polarity low level */
497
498 if (pdata && pdata->use_external_ref)
499 chip->command |= AD7291_EXT_REF;
500
501 indio_dev->name = id->name;
502 indio_dev->channels = ad7291_channels;
503 indio_dev->num_channels = ARRAY_SIZE(ad7291_channels);
504
505 indio_dev->dev.parent = &client->dev;
506 indio_dev->dev.of_node = client->dev.of_node;
507 indio_dev->info = &ad7291_info;
508 indio_dev->modes = INDIO_DIRECT_MODE;
509
510 ret = ad7291_i2c_write(chip, AD7291_COMMAND, AD7291_RESET);
511 if (ret) {
512 ret = -EIO;
513 goto error_disable_reg;
514 }
515
516 ret = ad7291_i2c_write(chip, AD7291_COMMAND, chip->command);
517 if (ret) {
518 ret = -EIO;
519 goto error_disable_reg;
520 }
521
522 if (client->irq > 0) {
523 ret = request_threaded_irq(client->irq,
524 NULL,
525 &ad7291_event_handler,
526 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
527 id->name,
528 indio_dev);
529 if (ret)
530 goto error_disable_reg;
531 }
532
533 ret = iio_device_register(indio_dev);
534 if (ret)
535 goto error_unreg_irq;
536
537 return 0;
538
539error_unreg_irq:
540 if (client->irq)
541 free_irq(client->irq, indio_dev);
542error_disable_reg:
543 if (chip->reg)
544 regulator_disable(chip->reg);
545
546 return ret;
547}
548
549static int ad7291_remove(struct i2c_client *client)
550{
551 struct iio_dev *indio_dev = i2c_get_clientdata(client);
552 struct ad7291_chip_info *chip = iio_priv(indio_dev);
553
554 iio_device_unregister(indio_dev);
555
556 if (client->irq)
557 free_irq(client->irq, indio_dev);
558
559 if (chip->reg)
560 regulator_disable(chip->reg);
561
562 return 0;
563}
564
565static const struct i2c_device_id ad7291_id[] = {
566 { "ad7291", 0 },
567 {}
568};
569
570MODULE_DEVICE_TABLE(i2c, ad7291_id);
571
572static struct i2c_driver ad7291_driver = {
573 .driver = {
574 .name = KBUILD_MODNAME,
575 },
576 .probe = ad7291_probe,
577 .remove = ad7291_remove,
578 .id_table = ad7291_id,
579};
580module_i2c_driver(ad7291_driver);
581
582MODULE_AUTHOR("Sonic Zhang <sonic.zhang@analog.com>");
583MODULE_DESCRIPTION("Analog Devices AD7291 ADC driver");
584MODULE_LICENSE("GPL v2");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * AD7291 8-Channel, I2C, 12-Bit SAR ADC with Temperature Sensor
4 *
5 * Copyright 2010-2011 Analog Devices Inc.
6 */
7
8#include <linux/device.h>
9#include <linux/err.h>
10#include <linux/i2c.h>
11#include <linux/interrupt.h>
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/mutex.h>
15#include <linux/regulator/consumer.h>
16#include <linux/slab.h>
17#include <linux/sysfs.h>
18
19#include <linux/iio/iio.h>
20#include <linux/iio/sysfs.h>
21#include <linux/iio/events.h>
22
23#include <linux/platform_data/ad7291.h>
24
25/*
26 * Simplified handling
27 *
28 * If no events enabled - single polled channel read
29 * If event enabled direct reads disable unless channel
30 * is in the read mask.
31 *
32 * The noise-delayed bit as per datasheet suggestion is always enabled.
33 */
34
35/*
36 * AD7291 registers definition
37 */
38#define AD7291_COMMAND 0x00
39#define AD7291_VOLTAGE 0x01
40#define AD7291_T_SENSE 0x02
41#define AD7291_T_AVERAGE 0x03
42#define AD7291_DATA_HIGH(x) ((x) * 3 + 0x4)
43#define AD7291_DATA_LOW(x) ((x) * 3 + 0x5)
44#define AD7291_HYST(x) ((x) * 3 + 0x6)
45#define AD7291_VOLTAGE_ALERT_STATUS 0x1F
46#define AD7291_T_ALERT_STATUS 0x20
47
48#define AD7291_BITS 12
49#define AD7291_VOLTAGE_LIMIT_COUNT 8
50
51
52/*
53 * AD7291 command
54 */
55#define AD7291_AUTOCYCLE BIT(0)
56#define AD7291_RESET BIT(1)
57#define AD7291_ALERT_CLEAR BIT(2)
58#define AD7291_ALERT_POLARITY BIT(3)
59#define AD7291_EXT_REF BIT(4)
60#define AD7291_NOISE_DELAY BIT(5)
61#define AD7291_T_SENSE_MASK BIT(7)
62#define AD7291_VOLTAGE_MASK GENMASK(15, 8)
63#define AD7291_VOLTAGE_OFFSET 8
64
65/*
66 * AD7291 value masks
67 */
68#define AD7291_VALUE_MASK GENMASK(11, 0)
69
70/*
71 * AD7291 alert register bits
72 */
73#define AD7291_T_LOW BIT(0)
74#define AD7291_T_HIGH BIT(1)
75#define AD7291_T_AVG_LOW BIT(2)
76#define AD7291_T_AVG_HIGH BIT(3)
77#define AD7291_V_LOW(x) BIT((x) * 2)
78#define AD7291_V_HIGH(x) BIT((x) * 2 + 1)
79
80
81struct ad7291_chip_info {
82 struct i2c_client *client;
83 struct regulator *reg;
84 u16 command;
85 u16 c_mask; /* Active voltage channels for events */
86 struct mutex state_lock;
87};
88
89static int ad7291_i2c_read(struct ad7291_chip_info *chip, u8 reg, u16 *data)
90{
91 struct i2c_client *client = chip->client;
92 int ret = 0;
93
94 ret = i2c_smbus_read_word_swapped(client, reg);
95 if (ret < 0) {
96 dev_err(&client->dev, "I2C read error\n");
97 return ret;
98 }
99
100 *data = ret;
101
102 return 0;
103}
104
105static int ad7291_i2c_write(struct ad7291_chip_info *chip, u8 reg, u16 data)
106{
107 return i2c_smbus_write_word_swapped(chip->client, reg, data);
108}
109
110static irqreturn_t ad7291_event_handler(int irq, void *private)
111{
112 struct iio_dev *indio_dev = private;
113 struct ad7291_chip_info *chip = iio_priv(private);
114 u16 t_status, v_status;
115 u16 command;
116 int i;
117 s64 timestamp = iio_get_time_ns(indio_dev);
118
119 if (ad7291_i2c_read(chip, AD7291_T_ALERT_STATUS, &t_status))
120 return IRQ_HANDLED;
121
122 if (ad7291_i2c_read(chip, AD7291_VOLTAGE_ALERT_STATUS, &v_status))
123 return IRQ_HANDLED;
124
125 if (!(t_status || v_status))
126 return IRQ_HANDLED;
127
128 command = chip->command | AD7291_ALERT_CLEAR;
129 ad7291_i2c_write(chip, AD7291_COMMAND, command);
130
131 command = chip->command & ~AD7291_ALERT_CLEAR;
132 ad7291_i2c_write(chip, AD7291_COMMAND, command);
133
134 /* For now treat t_sense and t_sense_average the same */
135 if ((t_status & AD7291_T_LOW) || (t_status & AD7291_T_AVG_LOW))
136 iio_push_event(indio_dev,
137 IIO_UNMOD_EVENT_CODE(IIO_TEMP,
138 0,
139 IIO_EV_TYPE_THRESH,
140 IIO_EV_DIR_FALLING),
141 timestamp);
142 if ((t_status & AD7291_T_HIGH) || (t_status & AD7291_T_AVG_HIGH))
143 iio_push_event(indio_dev,
144 IIO_UNMOD_EVENT_CODE(IIO_TEMP,
145 0,
146 IIO_EV_TYPE_THRESH,
147 IIO_EV_DIR_RISING),
148 timestamp);
149
150 for (i = 0; i < AD7291_VOLTAGE_LIMIT_COUNT; i++) {
151 if (v_status & AD7291_V_LOW(i))
152 iio_push_event(indio_dev,
153 IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
154 i,
155 IIO_EV_TYPE_THRESH,
156 IIO_EV_DIR_FALLING),
157 timestamp);
158 if (v_status & AD7291_V_HIGH(i))
159 iio_push_event(indio_dev,
160 IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
161 i,
162 IIO_EV_TYPE_THRESH,
163 IIO_EV_DIR_RISING),
164 timestamp);
165 }
166
167 return IRQ_HANDLED;
168}
169
170static unsigned int ad7291_threshold_reg(const struct iio_chan_spec *chan,
171 enum iio_event_direction dir,
172 enum iio_event_info info)
173{
174 unsigned int offset;
175
176 switch (chan->type) {
177 case IIO_VOLTAGE:
178 offset = chan->channel;
179 break;
180 case IIO_TEMP:
181 offset = AD7291_VOLTAGE_OFFSET;
182 break;
183 default:
184 return 0;
185 }
186
187 switch (info) {
188 case IIO_EV_INFO_VALUE:
189 if (dir == IIO_EV_DIR_FALLING)
190 return AD7291_DATA_HIGH(offset);
191 else
192 return AD7291_DATA_LOW(offset);
193 case IIO_EV_INFO_HYSTERESIS:
194 return AD7291_HYST(offset);
195 default:
196 break;
197 }
198 return 0;
199}
200
201static int ad7291_read_event_value(struct iio_dev *indio_dev,
202 const struct iio_chan_spec *chan,
203 enum iio_event_type type,
204 enum iio_event_direction dir,
205 enum iio_event_info info,
206 int *val, int *val2)
207{
208 struct ad7291_chip_info *chip = iio_priv(indio_dev);
209 int ret;
210 u16 uval;
211
212 ret = ad7291_i2c_read(chip, ad7291_threshold_reg(chan, dir, info),
213 &uval);
214 if (ret < 0)
215 return ret;
216
217 if (info == IIO_EV_INFO_HYSTERESIS || chan->type == IIO_VOLTAGE)
218 *val = uval & AD7291_VALUE_MASK;
219
220 else
221 *val = sign_extend32(uval, 11);
222
223 return IIO_VAL_INT;
224}
225
226static int ad7291_write_event_value(struct iio_dev *indio_dev,
227 const struct iio_chan_spec *chan,
228 enum iio_event_type type,
229 enum iio_event_direction dir,
230 enum iio_event_info info,
231 int val, int val2)
232{
233 struct ad7291_chip_info *chip = iio_priv(indio_dev);
234
235 if (info == IIO_EV_INFO_HYSTERESIS || chan->type == IIO_VOLTAGE) {
236 if (val > AD7291_VALUE_MASK || val < 0)
237 return -EINVAL;
238 } else {
239 if (val > 2047 || val < -2048)
240 return -EINVAL;
241 }
242
243 return ad7291_i2c_write(chip, ad7291_threshold_reg(chan, dir, info),
244 val);
245}
246
247static int ad7291_read_event_config(struct iio_dev *indio_dev,
248 const struct iio_chan_spec *chan,
249 enum iio_event_type type,
250 enum iio_event_direction dir)
251{
252 struct ad7291_chip_info *chip = iio_priv(indio_dev);
253 /*
254 * To be enabled the channel must simply be on. If any are enabled
255 * we are in continuous sampling mode
256 */
257
258 switch (chan->type) {
259 case IIO_VOLTAGE:
260 return !!(chip->c_mask & BIT(15 - chan->channel));
261 case IIO_TEMP:
262 /* always on */
263 return 1;
264 default:
265 return -EINVAL;
266 }
267
268}
269
270static int ad7291_write_event_config(struct iio_dev *indio_dev,
271 const struct iio_chan_spec *chan,
272 enum iio_event_type type,
273 enum iio_event_direction dir,
274 int state)
275{
276 int ret = 0;
277 struct ad7291_chip_info *chip = iio_priv(indio_dev);
278 unsigned int mask;
279 u16 regval;
280
281 mutex_lock(&chip->state_lock);
282 regval = chip->command;
283 /*
284 * To be enabled the channel must simply be on. If any are enabled
285 * use continuous sampling mode.
286 * Possible to disable temp as well but that makes single read tricky.
287 */
288
289 mask = BIT(15 - chan->channel);
290
291 switch (chan->type) {
292 case IIO_VOLTAGE:
293 if ((!state) && (chip->c_mask & mask))
294 chip->c_mask &= ~mask;
295 else if (state && (!(chip->c_mask & mask)))
296 chip->c_mask |= mask;
297 else
298 break;
299
300 regval &= ~AD7291_AUTOCYCLE;
301 regval |= chip->c_mask;
302 if (chip->c_mask) /* Enable autocycle? */
303 regval |= AD7291_AUTOCYCLE;
304
305 ret = ad7291_i2c_write(chip, AD7291_COMMAND, regval);
306 if (ret < 0)
307 goto error_ret;
308
309 chip->command = regval;
310 break;
311 default:
312 ret = -EINVAL;
313 }
314
315error_ret:
316 mutex_unlock(&chip->state_lock);
317 return ret;
318}
319
320static int ad7291_read_raw(struct iio_dev *indio_dev,
321 struct iio_chan_spec const *chan,
322 int *val,
323 int *val2,
324 long mask)
325{
326 int ret;
327 struct ad7291_chip_info *chip = iio_priv(indio_dev);
328 u16 regval;
329
330 switch (mask) {
331 case IIO_CHAN_INFO_RAW:
332 switch (chan->type) {
333 case IIO_VOLTAGE:
334 mutex_lock(&chip->state_lock);
335 /* If in autocycle mode drop through */
336 if (chip->command & AD7291_AUTOCYCLE) {
337 mutex_unlock(&chip->state_lock);
338 return -EBUSY;
339 }
340 /* Enable this channel alone */
341 regval = chip->command & (~AD7291_VOLTAGE_MASK);
342 regval |= BIT(15 - chan->channel);
343 ret = ad7291_i2c_write(chip, AD7291_COMMAND, regval);
344 if (ret < 0) {
345 mutex_unlock(&chip->state_lock);
346 return ret;
347 }
348 /* Read voltage */
349 ret = i2c_smbus_read_word_swapped(chip->client,
350 AD7291_VOLTAGE);
351 if (ret < 0) {
352 mutex_unlock(&chip->state_lock);
353 return ret;
354 }
355 *val = ret & AD7291_VALUE_MASK;
356 mutex_unlock(&chip->state_lock);
357 return IIO_VAL_INT;
358 case IIO_TEMP:
359 /* Assumes tsense bit of command register always set */
360 ret = i2c_smbus_read_word_swapped(chip->client,
361 AD7291_T_SENSE);
362 if (ret < 0)
363 return ret;
364 *val = sign_extend32(ret, 11);
365 return IIO_VAL_INT;
366 default:
367 return -EINVAL;
368 }
369 case IIO_CHAN_INFO_AVERAGE_RAW:
370 ret = i2c_smbus_read_word_swapped(chip->client,
371 AD7291_T_AVERAGE);
372 if (ret < 0)
373 return ret;
374 *val = sign_extend32(ret, 11);
375 return IIO_VAL_INT;
376 case IIO_CHAN_INFO_SCALE:
377 switch (chan->type) {
378 case IIO_VOLTAGE:
379 if (chip->reg) {
380 int vref;
381
382 vref = regulator_get_voltage(chip->reg);
383 if (vref < 0)
384 return vref;
385 *val = vref / 1000;
386 } else {
387 *val = 2500;
388 }
389 *val2 = AD7291_BITS;
390 return IIO_VAL_FRACTIONAL_LOG2;
391 case IIO_TEMP:
392 /*
393 * One LSB of the ADC corresponds to 0.25 deg C.
394 * The temperature reading is in 12-bit twos
395 * complement format
396 */
397 *val = 250;
398 return IIO_VAL_INT;
399 default:
400 return -EINVAL;
401 }
402 default:
403 return -EINVAL;
404 }
405}
406
407static const struct iio_event_spec ad7291_events[] = {
408 {
409 .type = IIO_EV_TYPE_THRESH,
410 .dir = IIO_EV_DIR_RISING,
411 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
412 BIT(IIO_EV_INFO_ENABLE),
413 }, {
414 .type = IIO_EV_TYPE_THRESH,
415 .dir = IIO_EV_DIR_FALLING,
416 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
417 BIT(IIO_EV_INFO_ENABLE),
418 }, {
419 .type = IIO_EV_TYPE_THRESH,
420 .dir = IIO_EV_DIR_EITHER,
421 .mask_separate = BIT(IIO_EV_INFO_HYSTERESIS),
422 },
423};
424
425#define AD7291_VOLTAGE_CHAN(_chan) \
426{ \
427 .type = IIO_VOLTAGE, \
428 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
429 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
430 .indexed = 1, \
431 .channel = _chan, \
432 .event_spec = ad7291_events, \
433 .num_event_specs = ARRAY_SIZE(ad7291_events), \
434}
435
436static const struct iio_chan_spec ad7291_channels[] = {
437 AD7291_VOLTAGE_CHAN(0),
438 AD7291_VOLTAGE_CHAN(1),
439 AD7291_VOLTAGE_CHAN(2),
440 AD7291_VOLTAGE_CHAN(3),
441 AD7291_VOLTAGE_CHAN(4),
442 AD7291_VOLTAGE_CHAN(5),
443 AD7291_VOLTAGE_CHAN(6),
444 AD7291_VOLTAGE_CHAN(7),
445 {
446 .type = IIO_TEMP,
447 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
448 BIT(IIO_CHAN_INFO_AVERAGE_RAW) |
449 BIT(IIO_CHAN_INFO_SCALE),
450 .indexed = 1,
451 .channel = 0,
452 .event_spec = ad7291_events,
453 .num_event_specs = ARRAY_SIZE(ad7291_events),
454 }
455};
456
457static const struct iio_info ad7291_info = {
458 .read_raw = &ad7291_read_raw,
459 .read_event_config = &ad7291_read_event_config,
460 .write_event_config = &ad7291_write_event_config,
461 .read_event_value = &ad7291_read_event_value,
462 .write_event_value = &ad7291_write_event_value,
463};
464
465static int ad7291_probe(struct i2c_client *client,
466 const struct i2c_device_id *id)
467{
468 struct ad7291_platform_data *pdata = client->dev.platform_data;
469 struct ad7291_chip_info *chip;
470 struct iio_dev *indio_dev;
471 int ret;
472
473 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
474 if (!indio_dev)
475 return -ENOMEM;
476 chip = iio_priv(indio_dev);
477
478 if (pdata && pdata->use_external_ref) {
479 chip->reg = devm_regulator_get(&client->dev, "vref");
480 if (IS_ERR(chip->reg))
481 return PTR_ERR(chip->reg);
482
483 ret = regulator_enable(chip->reg);
484 if (ret)
485 return ret;
486 }
487
488 mutex_init(&chip->state_lock);
489 /* this is only used for device removal purposes */
490 i2c_set_clientdata(client, indio_dev);
491
492 chip->client = client;
493
494 chip->command = AD7291_NOISE_DELAY |
495 AD7291_T_SENSE_MASK | /* Tsense always enabled */
496 AD7291_ALERT_POLARITY; /* set irq polarity low level */
497
498 if (pdata && pdata->use_external_ref)
499 chip->command |= AD7291_EXT_REF;
500
501 indio_dev->name = id->name;
502 indio_dev->channels = ad7291_channels;
503 indio_dev->num_channels = ARRAY_SIZE(ad7291_channels);
504
505 indio_dev->info = &ad7291_info;
506 indio_dev->modes = INDIO_DIRECT_MODE;
507
508 ret = ad7291_i2c_write(chip, AD7291_COMMAND, AD7291_RESET);
509 if (ret) {
510 ret = -EIO;
511 goto error_disable_reg;
512 }
513
514 ret = ad7291_i2c_write(chip, AD7291_COMMAND, chip->command);
515 if (ret) {
516 ret = -EIO;
517 goto error_disable_reg;
518 }
519
520 if (client->irq > 0) {
521 ret = request_threaded_irq(client->irq,
522 NULL,
523 &ad7291_event_handler,
524 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
525 id->name,
526 indio_dev);
527 if (ret)
528 goto error_disable_reg;
529 }
530
531 ret = iio_device_register(indio_dev);
532 if (ret)
533 goto error_unreg_irq;
534
535 return 0;
536
537error_unreg_irq:
538 if (client->irq)
539 free_irq(client->irq, indio_dev);
540error_disable_reg:
541 if (chip->reg)
542 regulator_disable(chip->reg);
543
544 return ret;
545}
546
547static int ad7291_remove(struct i2c_client *client)
548{
549 struct iio_dev *indio_dev = i2c_get_clientdata(client);
550 struct ad7291_chip_info *chip = iio_priv(indio_dev);
551
552 iio_device_unregister(indio_dev);
553
554 if (client->irq)
555 free_irq(client->irq, indio_dev);
556
557 if (chip->reg)
558 regulator_disable(chip->reg);
559
560 return 0;
561}
562
563static const struct i2c_device_id ad7291_id[] = {
564 { "ad7291", 0 },
565 {}
566};
567
568MODULE_DEVICE_TABLE(i2c, ad7291_id);
569
570static struct i2c_driver ad7291_driver = {
571 .driver = {
572 .name = KBUILD_MODNAME,
573 },
574 .probe = ad7291_probe,
575 .remove = ad7291_remove,
576 .id_table = ad7291_id,
577};
578module_i2c_driver(ad7291_driver);
579
580MODULE_AUTHOR("Sonic Zhang <sonic.zhang@analog.com>");
581MODULE_DESCRIPTION("Analog Devices AD7291 ADC driver");
582MODULE_LICENSE("GPL v2");