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8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/types.h>
11#include <linux/platform_device.h>
12#include <linux/mfd/dln2.h>
13
14#include <linux/iio/iio.h>
15#include <linux/iio/sysfs.h>
16#include <linux/iio/trigger.h>
17#include <linux/iio/trigger_consumer.h>
18#include <linux/iio/triggered_buffer.h>
19#include <linux/iio/buffer.h>
20#include <linux/iio/kfifo_buf.h>
21
22#define DLN2_ADC_MOD_NAME "dln2-adc"
23
24#define DLN2_ADC_ID 0x06
25
26#define DLN2_ADC_GET_CHANNEL_COUNT DLN2_CMD(0x01, DLN2_ADC_ID)
27#define DLN2_ADC_ENABLE DLN2_CMD(0x02, DLN2_ADC_ID)
28#define DLN2_ADC_DISABLE DLN2_CMD(0x03, DLN2_ADC_ID)
29#define DLN2_ADC_CHANNEL_ENABLE DLN2_CMD(0x05, DLN2_ADC_ID)
30#define DLN2_ADC_CHANNEL_DISABLE DLN2_CMD(0x06, DLN2_ADC_ID)
31#define DLN2_ADC_SET_RESOLUTION DLN2_CMD(0x08, DLN2_ADC_ID)
32#define DLN2_ADC_CHANNEL_GET_VAL DLN2_CMD(0x0A, DLN2_ADC_ID)
33#define DLN2_ADC_CHANNEL_GET_ALL_VAL DLN2_CMD(0x0B, DLN2_ADC_ID)
34#define DLN2_ADC_CHANNEL_SET_CFG DLN2_CMD(0x0C, DLN2_ADC_ID)
35#define DLN2_ADC_CHANNEL_GET_CFG DLN2_CMD(0x0D, DLN2_ADC_ID)
36#define DLN2_ADC_CONDITION_MET_EV DLN2_CMD(0x10, DLN2_ADC_ID)
37
38#define DLN2_ADC_EVENT_NONE 0
39#define DLN2_ADC_EVENT_BELOW 1
40#define DLN2_ADC_EVENT_LEVEL_ABOVE 2
41#define DLN2_ADC_EVENT_OUTSIDE 3
42#define DLN2_ADC_EVENT_INSIDE 4
43#define DLN2_ADC_EVENT_ALWAYS 5
44
45#define DLN2_ADC_MAX_CHANNELS 8
46#define DLN2_ADC_DATA_BITS 10
47
48
49
50
51
52struct dln2_adc_demux_table {
53 unsigned int from;
54 unsigned int to;
55 unsigned int length;
56};
57
58struct dln2_adc {
59 struct platform_device *pdev;
60 struct iio_chan_spec iio_channels[DLN2_ADC_MAX_CHANNELS + 1];
61 int port, trigger_chan;
62 struct iio_trigger *trig;
63 struct mutex mutex;
64
65 unsigned int sample_period;
66
67 unsigned int demux_count;
68 struct dln2_adc_demux_table demux[DLN2_ADC_MAX_CHANNELS];
69
70 unsigned int ts_pad_offset, ts_pad_length;
71};
72
73struct dln2_adc_port_chan {
74 u8 port;
75 u8 chan;
76};
77
78struct dln2_adc_get_all_vals {
79 __le16 channel_mask;
80 __le16 values[DLN2_ADC_MAX_CHANNELS];
81};
82
83static void dln2_adc_add_demux(struct dln2_adc *dln2,
84 unsigned int in_loc, unsigned int out_loc,
85 unsigned int length)
86{
87 struct dln2_adc_demux_table *p = dln2->demux_count ?
88 &dln2->demux[dln2->demux_count - 1] : NULL;
89
90 if (p && p->from + p->length == in_loc &&
91 p->to + p->length == out_loc) {
92 p->length += length;
93 } else if (dln2->demux_count < DLN2_ADC_MAX_CHANNELS) {
94 p = &dln2->demux[dln2->demux_count++];
95 p->from = in_loc;
96 p->to = out_loc;
97 p->length = length;
98 }
99}
100
101static void dln2_adc_update_demux(struct dln2_adc *dln2)
102{
103 int in_ind = -1, out_ind;
104 unsigned int in_loc = 0, out_loc = 0;
105 struct iio_dev *indio_dev = platform_get_drvdata(dln2->pdev);
106
107
108 dln2->demux_count = 0;
109
110
111 if (indio_dev->masklength &&
112 (*indio_dev->active_scan_mask & 0xff) == 0xff) {
113 dln2_adc_add_demux(dln2, 0, 0, 16);
114 dln2->ts_pad_offset = 0;
115 dln2->ts_pad_length = 0;
116 return;
117 }
118
119
120 for_each_set_bit(out_ind,
121 indio_dev->active_scan_mask,
122 indio_dev->masklength) {
123
124 if (out_ind == DLN2_ADC_MAX_CHANNELS)
125 break;
126 for (++in_ind; in_ind != out_ind; ++in_ind)
127 in_loc += 2;
128 dln2_adc_add_demux(dln2, in_loc, out_loc, 2);
129 out_loc += 2;
130 in_loc += 2;
131 }
132
133 if (indio_dev->scan_timestamp) {
134 size_t ts_offset = indio_dev->scan_bytes / sizeof(int64_t) - 1;
135
136 dln2->ts_pad_offset = out_loc;
137 dln2->ts_pad_length = ts_offset * sizeof(int64_t) - out_loc;
138 } else {
139 dln2->ts_pad_offset = 0;
140 dln2->ts_pad_length = 0;
141 }
142}
143
144static int dln2_adc_get_chan_count(struct dln2_adc *dln2)
145{
146 int ret;
147 u8 port = dln2->port;
148 u8 count;
149 int olen = sizeof(count);
150
151 ret = dln2_transfer(dln2->pdev, DLN2_ADC_GET_CHANNEL_COUNT,
152 &port, sizeof(port), &count, &olen);
153 if (ret < 0) {
154 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
155 return ret;
156 }
157 if (olen < sizeof(count))
158 return -EPROTO;
159
160 return count;
161}
162
163static int dln2_adc_set_port_resolution(struct dln2_adc *dln2)
164{
165 int ret;
166 struct dln2_adc_port_chan port_chan = {
167 .port = dln2->port,
168 .chan = DLN2_ADC_DATA_BITS,
169 };
170
171 ret = dln2_transfer_tx(dln2->pdev, DLN2_ADC_SET_RESOLUTION,
172 &port_chan, sizeof(port_chan));
173 if (ret < 0)
174 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
175
176 return ret;
177}
178
179static int dln2_adc_set_chan_enabled(struct dln2_adc *dln2,
180 int channel, bool enable)
181{
182 int ret;
183 struct dln2_adc_port_chan port_chan = {
184 .port = dln2->port,
185 .chan = channel,
186 };
187 u16 cmd = enable ? DLN2_ADC_CHANNEL_ENABLE : DLN2_ADC_CHANNEL_DISABLE;
188
189 ret = dln2_transfer_tx(dln2->pdev, cmd, &port_chan, sizeof(port_chan));
190 if (ret < 0)
191 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
192
193 return ret;
194}
195
196static int dln2_adc_set_port_enabled(struct dln2_adc *dln2, bool enable,
197 u16 *conflict_out)
198{
199 int ret;
200 u8 port = dln2->port;
201 __le16 conflict;
202 int olen = sizeof(conflict);
203 u16 cmd = enable ? DLN2_ADC_ENABLE : DLN2_ADC_DISABLE;
204
205 if (conflict_out)
206 *conflict_out = 0;
207
208 ret = dln2_transfer(dln2->pdev, cmd, &port, sizeof(port),
209 &conflict, &olen);
210 if (ret < 0) {
211 dev_dbg(&dln2->pdev->dev, "Problem in %s(%d)\n",
212 __func__, (int)enable);
213 if (conflict_out && enable && olen >= sizeof(conflict))
214 *conflict_out = le16_to_cpu(conflict);
215 return ret;
216 }
217 if (enable && olen < sizeof(conflict))
218 return -EPROTO;
219
220 return ret;
221}
222
223static int dln2_adc_set_chan_period(struct dln2_adc *dln2,
224 unsigned int channel, unsigned int period)
225{
226 int ret;
227 struct {
228 struct dln2_adc_port_chan port_chan;
229 __u8 type;
230 __le16 period;
231 __le16 low;
232 __le16 high;
233 } __packed set_cfg = {
234 .port_chan.port = dln2->port,
235 .port_chan.chan = channel,
236 .type = period ? DLN2_ADC_EVENT_ALWAYS : DLN2_ADC_EVENT_NONE,
237 .period = cpu_to_le16(period)
238 };
239
240 ret = dln2_transfer_tx(dln2->pdev, DLN2_ADC_CHANNEL_SET_CFG,
241 &set_cfg, sizeof(set_cfg));
242 if (ret < 0)
243 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
244
245 return ret;
246}
247
248static int dln2_adc_read(struct dln2_adc *dln2, unsigned int channel)
249{
250 int ret, i;
251 struct iio_dev *indio_dev = platform_get_drvdata(dln2->pdev);
252 u16 conflict;
253 __le16 value;
254 int olen = sizeof(value);
255 struct dln2_adc_port_chan port_chan = {
256 .port = dln2->port,
257 .chan = channel,
258 };
259
260 ret = iio_device_claim_direct_mode(indio_dev);
261 if (ret < 0)
262 return ret;
263
264 ret = dln2_adc_set_chan_enabled(dln2, channel, true);
265 if (ret < 0)
266 goto release_direct;
267
268 ret = dln2_adc_set_port_enabled(dln2, true, &conflict);
269 if (ret < 0) {
270 if (conflict) {
271 dev_err(&dln2->pdev->dev,
272 "ADC pins conflict with mask %04X\n",
273 (int)conflict);
274 ret = -EBUSY;
275 }
276 goto disable_chan;
277 }
278
279
280
281
282
283 for (i = 0; i < 2; ++i) {
284 ret = dln2_transfer(dln2->pdev, DLN2_ADC_CHANNEL_GET_VAL,
285 &port_chan, sizeof(port_chan),
286 &value, &olen);
287 if (ret < 0) {
288 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
289 goto disable_port;
290 }
291 if (olen < sizeof(value)) {
292 ret = -EPROTO;
293 goto disable_port;
294 }
295 }
296
297 ret = le16_to_cpu(value);
298
299disable_port:
300 dln2_adc_set_port_enabled(dln2, false, NULL);
301disable_chan:
302 dln2_adc_set_chan_enabled(dln2, channel, false);
303release_direct:
304 iio_device_release_direct_mode(indio_dev);
305
306 return ret;
307}
308
309static int dln2_adc_read_all(struct dln2_adc *dln2,
310 struct dln2_adc_get_all_vals *get_all_vals)
311{
312 int ret;
313 __u8 port = dln2->port;
314 int olen = sizeof(*get_all_vals);
315
316 ret = dln2_transfer(dln2->pdev, DLN2_ADC_CHANNEL_GET_ALL_VAL,
317 &port, sizeof(port), get_all_vals, &olen);
318 if (ret < 0) {
319 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
320 return ret;
321 }
322 if (olen < sizeof(*get_all_vals))
323 return -EPROTO;
324
325 return ret;
326}
327
328static int dln2_adc_read_raw(struct iio_dev *indio_dev,
329 struct iio_chan_spec const *chan,
330 int *val,
331 int *val2,
332 long mask)
333{
334 int ret;
335 unsigned int microhertz;
336 struct dln2_adc *dln2 = iio_priv(indio_dev);
337
338 switch (mask) {
339 case IIO_CHAN_INFO_RAW:
340 mutex_lock(&dln2->mutex);
341 ret = dln2_adc_read(dln2, chan->channel);
342 mutex_unlock(&dln2->mutex);
343
344 if (ret < 0)
345 return ret;
346
347 *val = ret;
348 return IIO_VAL_INT;
349
350 case IIO_CHAN_INFO_SCALE:
351
352
353
354
355 *val = 0;
356 *val2 = 3222656;
357 return IIO_VAL_INT_PLUS_NANO;
358
359 case IIO_CHAN_INFO_SAMP_FREQ:
360 if (dln2->sample_period) {
361 microhertz = 1000000000 / dln2->sample_period;
362 *val = microhertz / 1000000;
363 *val2 = microhertz % 1000000;
364 } else {
365 *val = 0;
366 *val2 = 0;
367 }
368
369 return IIO_VAL_INT_PLUS_MICRO;
370
371 default:
372 return -EINVAL;
373 }
374}
375
376static int dln2_adc_write_raw(struct iio_dev *indio_dev,
377 struct iio_chan_spec const *chan,
378 int val,
379 int val2,
380 long mask)
381{
382 int ret;
383 unsigned int microhertz;
384 struct dln2_adc *dln2 = iio_priv(indio_dev);
385
386 switch (mask) {
387 case IIO_CHAN_INFO_SAMP_FREQ:
388 microhertz = 1000000 * val + val2;
389
390 mutex_lock(&dln2->mutex);
391
392 dln2->sample_period =
393 microhertz ? 1000000000 / microhertz : UINT_MAX;
394 if (dln2->sample_period > 65535) {
395 dln2->sample_period = 65535;
396 dev_warn(&dln2->pdev->dev,
397 "clamping period to 65535ms\n");
398 }
399
400
401
402
403
404
405
406
407 if (dln2->trigger_chan != -1)
408 ret = dln2_adc_set_chan_period(dln2,
409 dln2->trigger_chan, dln2->sample_period);
410 else
411 ret = 0;
412
413 mutex_unlock(&dln2->mutex);
414
415 return ret;
416
417 default:
418 return -EINVAL;
419 }
420}
421
422static int dln2_update_scan_mode(struct iio_dev *indio_dev,
423 const unsigned long *scan_mask)
424{
425 struct dln2_adc *dln2 = iio_priv(indio_dev);
426 int chan_count = indio_dev->num_channels - 1;
427 int ret, i, j;
428
429 mutex_lock(&dln2->mutex);
430
431 for (i = 0; i < chan_count; ++i) {
432 ret = dln2_adc_set_chan_enabled(dln2, i,
433 test_bit(i, scan_mask));
434 if (ret < 0) {
435 for (j = 0; j < i; ++j)
436 dln2_adc_set_chan_enabled(dln2, j, false);
437 mutex_unlock(&dln2->mutex);
438 dev_err(&dln2->pdev->dev,
439 "Unable to enable ADC channel %d\n", i);
440 return -EBUSY;
441 }
442 }
443
444 dln2_adc_update_demux(dln2);
445
446 mutex_unlock(&dln2->mutex);
447
448 return 0;
449}
450
451#define DLN2_ADC_CHAN(lval, idx) { \
452 lval.type = IIO_VOLTAGE; \
453 lval.channel = idx; \
454 lval.indexed = 1; \
455 lval.info_mask_separate = BIT(IIO_CHAN_INFO_RAW); \
456 lval.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE) | \
457 BIT(IIO_CHAN_INFO_SAMP_FREQ); \
458 lval.scan_index = idx; \
459 lval.scan_type.sign = 'u'; \
460 lval.scan_type.realbits = DLN2_ADC_DATA_BITS; \
461 lval.scan_type.storagebits = 16; \
462 lval.scan_type.endianness = IIO_LE; \
463}
464
465
466#define IIO_CHAN_SOFT_TIMESTAMP_ASSIGN(lval, _si) { \
467 lval.type = IIO_TIMESTAMP; \
468 lval.channel = -1; \
469 lval.scan_index = _si; \
470 lval.scan_type.sign = 's'; \
471 lval.scan_type.realbits = 64; \
472 lval.scan_type.storagebits = 64; \
473}
474
475static const struct iio_info dln2_adc_info = {
476 .read_raw = dln2_adc_read_raw,
477 .write_raw = dln2_adc_write_raw,
478 .update_scan_mode = dln2_update_scan_mode,
479};
480
481static irqreturn_t dln2_adc_trigger_h(int irq, void *p)
482{
483 struct iio_poll_func *pf = p;
484 struct iio_dev *indio_dev = pf->indio_dev;
485 struct {
486 __le16 values[DLN2_ADC_MAX_CHANNELS];
487 int64_t timestamp_space;
488 } data;
489 struct dln2_adc_get_all_vals dev_data;
490 struct dln2_adc *dln2 = iio_priv(indio_dev);
491 const struct dln2_adc_demux_table *t;
492 int ret, i;
493
494 mutex_lock(&dln2->mutex);
495 ret = dln2_adc_read_all(dln2, &dev_data);
496 mutex_unlock(&dln2->mutex);
497 if (ret < 0)
498 goto done;
499
500
501 for (i = 0; i < dln2->demux_count; ++i) {
502 t = &dln2->demux[i];
503 memcpy((void *)data.values + t->to,
504 (void *)dev_data.values + t->from, t->length);
505 }
506
507
508 if (dln2->ts_pad_length)
509 memset((void *)data.values + dln2->ts_pad_offset,
510 0, dln2->ts_pad_length);
511
512 iio_push_to_buffers_with_timestamp(indio_dev, &data,
513 iio_get_time_ns(indio_dev));
514
515done:
516 iio_trigger_notify_done(indio_dev->trig);
517 return IRQ_HANDLED;
518}
519
520static int dln2_adc_triggered_buffer_postenable(struct iio_dev *indio_dev)
521{
522 int ret;
523 struct dln2_adc *dln2 = iio_priv(indio_dev);
524 u16 conflict;
525 unsigned int trigger_chan;
526
527 mutex_lock(&dln2->mutex);
528
529
530 ret = dln2_adc_set_port_enabled(dln2, true, &conflict);
531 if (ret < 0) {
532 mutex_unlock(&dln2->mutex);
533 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
534 if (conflict) {
535 dev_err(&dln2->pdev->dev,
536 "ADC pins conflict with mask %04X\n",
537 (int)conflict);
538 ret = -EBUSY;
539 }
540 return ret;
541 }
542
543
544 trigger_chan = find_first_bit(indio_dev->active_scan_mask,
545 indio_dev->masklength);
546 if (trigger_chan < DLN2_ADC_MAX_CHANNELS) {
547 dln2->trigger_chan = trigger_chan;
548 ret = dln2_adc_set_chan_period(dln2, dln2->trigger_chan,
549 dln2->sample_period);
550 mutex_unlock(&dln2->mutex);
551 if (ret < 0) {
552 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
553 return ret;
554 }
555 } else {
556 dln2->trigger_chan = -1;
557 mutex_unlock(&dln2->mutex);
558 }
559
560 return 0;
561}
562
563static int dln2_adc_triggered_buffer_predisable(struct iio_dev *indio_dev)
564{
565 int ret;
566 struct dln2_adc *dln2 = iio_priv(indio_dev);
567
568 mutex_lock(&dln2->mutex);
569
570
571 if (dln2->trigger_chan != -1) {
572 dln2_adc_set_chan_period(dln2, dln2->trigger_chan, 0);
573 dln2->trigger_chan = -1;
574 }
575
576
577 ret = dln2_adc_set_port_enabled(dln2, false, NULL);
578
579 mutex_unlock(&dln2->mutex);
580 if (ret < 0)
581 dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
582
583 return ret;
584}
585
586static const struct iio_buffer_setup_ops dln2_adc_buffer_setup_ops = {
587 .postenable = dln2_adc_triggered_buffer_postenable,
588 .predisable = dln2_adc_triggered_buffer_predisable,
589};
590
591static void dln2_adc_event(struct platform_device *pdev, u16 echo,
592 const void *data, int len)
593{
594 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
595 struct dln2_adc *dln2 = iio_priv(indio_dev);
596
597
598 iio_trigger_poll(dln2->trig);
599}
600
601static int dln2_adc_probe(struct platform_device *pdev)
602{
603 struct device *dev = &pdev->dev;
604 struct dln2_adc *dln2;
605 struct dln2_platform_data *pdata = dev_get_platdata(&pdev->dev);
606 struct iio_dev *indio_dev;
607 int i, ret, chans;
608
609 indio_dev = devm_iio_device_alloc(dev, sizeof(*dln2));
610 if (!indio_dev) {
611 dev_err(dev, "failed allocating iio device\n");
612 return -ENOMEM;
613 }
614
615 dln2 = iio_priv(indio_dev);
616 dln2->pdev = pdev;
617 dln2->port = pdata->port;
618 dln2->trigger_chan = -1;
619 mutex_init(&dln2->mutex);
620
621 platform_set_drvdata(pdev, indio_dev);
622
623 ret = dln2_adc_set_port_resolution(dln2);
624 if (ret < 0) {
625 dev_err(dev, "failed to set ADC resolution to 10 bits\n");
626 return ret;
627 }
628
629 chans = dln2_adc_get_chan_count(dln2);
630 if (chans < 0) {
631 dev_err(dev, "failed to get channel count: %d\n", chans);
632 return chans;
633 }
634 if (chans > DLN2_ADC_MAX_CHANNELS) {
635 chans = DLN2_ADC_MAX_CHANNELS;
636 dev_warn(dev, "clamping channels to %d\n",
637 DLN2_ADC_MAX_CHANNELS);
638 }
639
640 for (i = 0; i < chans; ++i)
641 DLN2_ADC_CHAN(dln2->iio_channels[i], i)
642 IIO_CHAN_SOFT_TIMESTAMP_ASSIGN(dln2->iio_channels[i], i);
643
644 indio_dev->name = DLN2_ADC_MOD_NAME;
645 indio_dev->info = &dln2_adc_info;
646 indio_dev->modes = INDIO_DIRECT_MODE;
647 indio_dev->channels = dln2->iio_channels;
648 indio_dev->num_channels = chans + 1;
649 indio_dev->setup_ops = &dln2_adc_buffer_setup_ops;
650
651 dln2->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
652 indio_dev->name,
653 iio_device_id(indio_dev));
654 if (!dln2->trig) {
655 dev_err(dev, "failed to allocate trigger\n");
656 return -ENOMEM;
657 }
658 iio_trigger_set_drvdata(dln2->trig, dln2);
659 devm_iio_trigger_register(dev, dln2->trig);
660 iio_trigger_set_immutable(indio_dev, dln2->trig);
661
662 ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
663 dln2_adc_trigger_h,
664 &dln2_adc_buffer_setup_ops);
665 if (ret) {
666 dev_err(dev, "failed to allocate triggered buffer: %d\n", ret);
667 return ret;
668 }
669
670 ret = dln2_register_event_cb(pdev, DLN2_ADC_CONDITION_MET_EV,
671 dln2_adc_event);
672 if (ret) {
673 dev_err(dev, "failed to setup DLN2 periodic event: %d\n", ret);
674 return ret;
675 }
676
677 ret = iio_device_register(indio_dev);
678 if (ret) {
679 dev_err(dev, "failed to register iio device: %d\n", ret);
680 goto unregister_event;
681 }
682
683 return ret;
684
685unregister_event:
686 dln2_unregister_event_cb(pdev, DLN2_ADC_CONDITION_MET_EV);
687
688 return ret;
689}
690
691static int dln2_adc_remove(struct platform_device *pdev)
692{
693 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
694
695 iio_device_unregister(indio_dev);
696 dln2_unregister_event_cb(pdev, DLN2_ADC_CONDITION_MET_EV);
697 return 0;
698}
699
700static struct platform_driver dln2_adc_driver = {
701 .driver.name = DLN2_ADC_MOD_NAME,
702 .probe = dln2_adc_probe,
703 .remove = dln2_adc_remove,
704};
705
706module_platform_driver(dln2_adc_driver);
707
708MODULE_AUTHOR("Jack Andersen <jackoalan@gmail.com");
709MODULE_DESCRIPTION("Driver for the Diolan DLN2 ADC interface");
710MODULE_LICENSE("GPL v2");
711MODULE_ALIAS("platform:dln2-adc");
712
