xref: /linux/sound/usb/caiaq/audio.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *   Copyright (c) 2006-2008 Daniel Mack, Karsten Wiese
4 */
5 
6 #include <linux/device.h>
7 #include <linux/spinlock.h>
8 #include <linux/slab.h>
9 #include <linux/init.h>
10 #include <linux/usb.h>
11 #include <sound/core.h>
12 #include <sound/pcm.h>
13 
14 #include "device.h"
15 #include "audio.h"
16 
17 #define N_URBS			32
18 #define CLOCK_DRIFT_TOLERANCE	5
19 #define FRAMES_PER_URB		8
20 #define BYTES_PER_FRAME		512
21 #define CHANNELS_PER_STREAM	2
22 #define BYTES_PER_SAMPLE	3
23 #define BYTES_PER_SAMPLE_USB	4
24 #define MAX_BUFFER_SIZE		(128*1024)
25 #define MAX_ENDPOINT_SIZE	512
26 
27 #define ENDPOINT_CAPTURE	2
28 #define ENDPOINT_PLAYBACK	6
29 
30 #define MAKE_CHECKBYTE(cdev,stream,i) \
31 	(stream << 1) | (~(i / (cdev->n_streams * BYTES_PER_SAMPLE_USB)) & 1)
32 
33 static const struct snd_pcm_hardware snd_usb_caiaq_pcm_hardware = {
34 	.info 		= (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
35 			   SNDRV_PCM_INFO_BLOCK_TRANSFER),
36 	.formats 	= SNDRV_PCM_FMTBIT_S24_3BE,
37 	.rates 		= (SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000 |
38 			   SNDRV_PCM_RATE_96000),
39 	.rate_min	= 44100,
40 	.rate_max	= 0, /* will overwrite later */
41 	.channels_min	= CHANNELS_PER_STREAM,
42 	.channels_max	= CHANNELS_PER_STREAM,
43 	.buffer_bytes_max = MAX_BUFFER_SIZE,
44 	.period_bytes_min = 128,
45 	.period_bytes_max = MAX_BUFFER_SIZE,
46 	.periods_min	= 1,
47 	.periods_max	= 1024,
48 };
49 
50 static void
51 activate_substream(struct snd_usb_caiaqdev *cdev,
52 	           struct snd_pcm_substream *sub)
53 {
54 	spin_lock(&cdev->spinlock);
55 
56 	if (sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
57 		cdev->sub_playback[sub->number] = sub;
58 	else
59 		cdev->sub_capture[sub->number] = sub;
60 
61 	spin_unlock(&cdev->spinlock);
62 }
63 
64 static void
65 deactivate_substream(struct snd_usb_caiaqdev *cdev,
66 		     struct snd_pcm_substream *sub)
67 {
68 	unsigned long flags;
69 	spin_lock_irqsave(&cdev->spinlock, flags);
70 
71 	if (sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
72 		cdev->sub_playback[sub->number] = NULL;
73 	else
74 		cdev->sub_capture[sub->number] = NULL;
75 
76 	spin_unlock_irqrestore(&cdev->spinlock, flags);
77 }
78 
79 static int
80 all_substreams_zero(struct snd_pcm_substream **subs)
81 {
82 	int i;
83 	for (i = 0; i < MAX_STREAMS; i++)
84 		if (subs[i] != NULL)
85 			return 0;
86 	return 1;
87 }
88 
89 static int stream_start(struct snd_usb_caiaqdev *cdev)
90 {
91 	int i, ret;
92 	struct device *dev = caiaqdev_to_dev(cdev);
93 
94 	dev_dbg(dev, "%s(%p)\n", __func__, cdev);
95 
96 	if (cdev->streaming)
97 		return -EINVAL;
98 
99 	memset(cdev->sub_playback, 0, sizeof(cdev->sub_playback));
100 	memset(cdev->sub_capture, 0, sizeof(cdev->sub_capture));
101 	cdev->input_panic = 0;
102 	cdev->output_panic = 0;
103 	cdev->first_packet = 4;
104 	cdev->streaming = 1;
105 	cdev->warned = 0;
106 
107 	for (i = 0; i < N_URBS; i++) {
108 		ret = usb_submit_urb(cdev->data_urbs_in[i], GFP_ATOMIC);
109 		if (ret) {
110 			dev_err(dev, "unable to trigger read #%d! (ret %d)\n",
111 				i, ret);
112 			cdev->streaming = 0;
113 			return -EPIPE;
114 		}
115 	}
116 
117 	return 0;
118 }
119 
120 static void stream_stop(struct snd_usb_caiaqdev *cdev)
121 {
122 	int i;
123 	struct device *dev = caiaqdev_to_dev(cdev);
124 
125 	dev_dbg(dev, "%s(%p)\n", __func__, cdev);
126 	if (!cdev->streaming)
127 		return;
128 
129 	cdev->streaming = 0;
130 
131 	for (i = 0; i < N_URBS; i++) {
132 		usb_kill_urb(cdev->data_urbs_in[i]);
133 
134 		if (test_bit(i, &cdev->outurb_active_mask))
135 			usb_kill_urb(cdev->data_urbs_out[i]);
136 	}
137 
138 	cdev->outurb_active_mask = 0;
139 }
140 
141 static int snd_usb_caiaq_substream_open(struct snd_pcm_substream *substream)
142 {
143 	struct snd_usb_caiaqdev *cdev = snd_pcm_substream_chip(substream);
144 	struct device *dev = caiaqdev_to_dev(cdev);
145 
146 	dev_dbg(dev, "%s(%p)\n", __func__, substream);
147 	substream->runtime->hw = cdev->pcm_info;
148 	snd_pcm_limit_hw_rates(substream->runtime);
149 
150 	return 0;
151 }
152 
153 static int snd_usb_caiaq_substream_close(struct snd_pcm_substream *substream)
154 {
155 	struct snd_usb_caiaqdev *cdev = snd_pcm_substream_chip(substream);
156 	struct device *dev = caiaqdev_to_dev(cdev);
157 
158 	dev_dbg(dev, "%s(%p)\n", __func__, substream);
159 	if (all_substreams_zero(cdev->sub_playback) &&
160 	    all_substreams_zero(cdev->sub_capture)) {
161 		/* when the last client has stopped streaming,
162 		 * all sample rates are allowed again */
163 		stream_stop(cdev);
164 		cdev->pcm_info.rates = cdev->samplerates;
165 	}
166 
167 	return 0;
168 }
169 
170 static int snd_usb_caiaq_pcm_hw_free(struct snd_pcm_substream *sub)
171 {
172 	struct snd_usb_caiaqdev *cdev = snd_pcm_substream_chip(sub);
173 	deactivate_substream(cdev, sub);
174 	return 0;
175 }
176 
177 static int snd_usb_caiaq_pcm_prepare(struct snd_pcm_substream *substream)
178 {
179 	int bytes_per_sample, bpp, ret;
180 	int index = substream->number;
181 	struct snd_usb_caiaqdev *cdev = snd_pcm_substream_chip(substream);
182 	struct snd_pcm_runtime *runtime = substream->runtime;
183 	struct device *dev = caiaqdev_to_dev(cdev);
184 
185 	dev_dbg(dev, "%s(%p)\n", __func__, substream);
186 
187 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
188 		int out_pos;
189 
190 		switch (cdev->spec.data_alignment) {
191 		case 0:
192 		case 2:
193 			out_pos = BYTES_PER_SAMPLE + 1;
194 			break;
195 		case 3:
196 		default:
197 			out_pos = 0;
198 			break;
199 		}
200 
201 		cdev->period_out_count[index] = out_pos;
202 		cdev->audio_out_buf_pos[index] = out_pos;
203 	} else {
204 		int in_pos;
205 
206 		switch (cdev->spec.data_alignment) {
207 		case 0:
208 			in_pos = BYTES_PER_SAMPLE + 2;
209 			break;
210 		case 2:
211 			in_pos = BYTES_PER_SAMPLE;
212 			break;
213 		case 3:
214 		default:
215 			in_pos = 0;
216 			break;
217 		}
218 
219 		cdev->period_in_count[index] = in_pos;
220 		cdev->audio_in_buf_pos[index] = in_pos;
221 	}
222 
223 	if (cdev->streaming)
224 		return 0;
225 
226 	/* the first client that opens a stream defines the sample rate
227 	 * setting for all subsequent calls, until the last client closed. */
228 	cdev->pcm_info.rates = snd_pcm_rate_to_rate_bit(runtime->rate);
229 	snd_pcm_limit_hw_rates(runtime);
230 
231 	bytes_per_sample = BYTES_PER_SAMPLE;
232 	if (cdev->spec.data_alignment >= 2)
233 		bytes_per_sample++;
234 
235 	bpp = ((runtime->rate / 8000) + CLOCK_DRIFT_TOLERANCE)
236 		* bytes_per_sample * CHANNELS_PER_STREAM * cdev->n_streams;
237 
238 	if (bpp > MAX_ENDPOINT_SIZE)
239 		bpp = MAX_ENDPOINT_SIZE;
240 
241 	ret = snd_usb_caiaq_set_audio_params(cdev, runtime->rate,
242 					     runtime->sample_bits, bpp);
243 	if (ret)
244 		return ret;
245 
246 	ret = stream_start(cdev);
247 	if (ret)
248 		return ret;
249 
250 	cdev->output_running = 0;
251 	wait_event_timeout(cdev->prepare_wait_queue, cdev->output_running, HZ);
252 	if (!cdev->output_running) {
253 		stream_stop(cdev);
254 		return -EPIPE;
255 	}
256 
257 	return 0;
258 }
259 
260 static int snd_usb_caiaq_pcm_trigger(struct snd_pcm_substream *sub, int cmd)
261 {
262 	struct snd_usb_caiaqdev *cdev = snd_pcm_substream_chip(sub);
263 	struct device *dev = caiaqdev_to_dev(cdev);
264 
265 	dev_dbg(dev, "%s(%p) cmd %d\n", __func__, sub, cmd);
266 
267 	switch (cmd) {
268 	case SNDRV_PCM_TRIGGER_START:
269 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
270 		activate_substream(cdev, sub);
271 		break;
272 	case SNDRV_PCM_TRIGGER_STOP:
273 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
274 		deactivate_substream(cdev, sub);
275 		break;
276 	default:
277 		return -EINVAL;
278 	}
279 
280 	return 0;
281 }
282 
283 static snd_pcm_uframes_t
284 snd_usb_caiaq_pcm_pointer(struct snd_pcm_substream *sub)
285 {
286 	int index = sub->number;
287 	struct snd_usb_caiaqdev *cdev = snd_pcm_substream_chip(sub);
288 	snd_pcm_uframes_t ptr;
289 
290 	spin_lock(&cdev->spinlock);
291 
292 	if (cdev->input_panic || cdev->output_panic) {
293 		ptr = SNDRV_PCM_POS_XRUN;
294 		goto unlock;
295 	}
296 
297 	if (sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
298 		ptr = bytes_to_frames(sub->runtime,
299 					cdev->audio_out_buf_pos[index]);
300 	else
301 		ptr = bytes_to_frames(sub->runtime,
302 					cdev->audio_in_buf_pos[index]);
303 
304 unlock:
305 	spin_unlock(&cdev->spinlock);
306 	return ptr;
307 }
308 
309 /* operators for both playback and capture */
310 static const struct snd_pcm_ops snd_usb_caiaq_ops = {
311 	.open =		snd_usb_caiaq_substream_open,
312 	.close =	snd_usb_caiaq_substream_close,
313 	.hw_free =	snd_usb_caiaq_pcm_hw_free,
314 	.prepare =	snd_usb_caiaq_pcm_prepare,
315 	.trigger =	snd_usb_caiaq_pcm_trigger,
316 	.pointer =	snd_usb_caiaq_pcm_pointer,
317 };
318 
319 static void check_for_elapsed_periods(struct snd_usb_caiaqdev *cdev,
320 				      struct snd_pcm_substream **subs)
321 {
322 	int stream, pb, *cnt;
323 	struct snd_pcm_substream *sub;
324 
325 	for (stream = 0; stream < cdev->n_streams; stream++) {
326 		sub = subs[stream];
327 		if (!sub)
328 			continue;
329 
330 		pb = snd_pcm_lib_period_bytes(sub);
331 		cnt = (sub->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
332 					&cdev->period_out_count[stream] :
333 					&cdev->period_in_count[stream];
334 
335 		if (*cnt >= pb) {
336 			snd_pcm_period_elapsed(sub);
337 			*cnt %= pb;
338 		}
339 	}
340 }
341 
342 static void read_in_urb_mode0(struct snd_usb_caiaqdev *cdev,
343 			      const struct urb *urb,
344 			      const struct usb_iso_packet_descriptor *iso)
345 {
346 	unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
347 	struct snd_pcm_substream *sub;
348 	int stream, i;
349 
350 	if (all_substreams_zero(cdev->sub_capture))
351 		return;
352 
353 	for (i = 0; i < iso->actual_length;) {
354 		for (stream = 0; stream < cdev->n_streams; stream++, i++) {
355 			sub = cdev->sub_capture[stream];
356 			if (sub) {
357 				struct snd_pcm_runtime *rt = sub->runtime;
358 				char *audio_buf = rt->dma_area;
359 				int sz = frames_to_bytes(rt, rt->buffer_size);
360 				audio_buf[cdev->audio_in_buf_pos[stream]++]
361 					= usb_buf[i];
362 				cdev->period_in_count[stream]++;
363 				if (cdev->audio_in_buf_pos[stream] == sz)
364 					cdev->audio_in_buf_pos[stream] = 0;
365 			}
366 		}
367 	}
368 }
369 
370 static void read_in_urb_mode2(struct snd_usb_caiaqdev *cdev,
371 			      const struct urb *urb,
372 			      const struct usb_iso_packet_descriptor *iso)
373 {
374 	unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
375 	unsigned char check_byte;
376 	struct snd_pcm_substream *sub;
377 	int stream, i;
378 
379 	for (i = 0; i < iso->actual_length;) {
380 		if (i % (cdev->n_streams * BYTES_PER_SAMPLE_USB) == 0) {
381 			for (stream = 0;
382 			     stream < cdev->n_streams;
383 			     stream++, i++) {
384 				if (cdev->first_packet)
385 					continue;
386 
387 				check_byte = MAKE_CHECKBYTE(cdev, stream, i);
388 
389 				if ((usb_buf[i] & 0x3f) != check_byte)
390 					cdev->input_panic = 1;
391 
392 				if (usb_buf[i] & 0x80)
393 					cdev->output_panic = 1;
394 			}
395 		}
396 		cdev->first_packet = 0;
397 
398 		for (stream = 0; stream < cdev->n_streams; stream++, i++) {
399 			sub = cdev->sub_capture[stream];
400 			if (cdev->input_panic)
401 				usb_buf[i] = 0;
402 
403 			if (sub) {
404 				struct snd_pcm_runtime *rt = sub->runtime;
405 				char *audio_buf = rt->dma_area;
406 				int sz = frames_to_bytes(rt, rt->buffer_size);
407 				audio_buf[cdev->audio_in_buf_pos[stream]++] =
408 					usb_buf[i];
409 				cdev->period_in_count[stream]++;
410 				if (cdev->audio_in_buf_pos[stream] == sz)
411 					cdev->audio_in_buf_pos[stream] = 0;
412 			}
413 		}
414 	}
415 }
416 
417 static void read_in_urb_mode3(struct snd_usb_caiaqdev *cdev,
418 			      const struct urb *urb,
419 			      const struct usb_iso_packet_descriptor *iso)
420 {
421 	unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
422 	struct device *dev = caiaqdev_to_dev(cdev);
423 	int stream, i;
424 
425 	/* paranoia check */
426 	if (iso->actual_length % (BYTES_PER_SAMPLE_USB * CHANNELS_PER_STREAM))
427 		return;
428 
429 	for (i = 0; i < iso->actual_length;) {
430 		for (stream = 0; stream < cdev->n_streams; stream++) {
431 			struct snd_pcm_substream *sub = cdev->sub_capture[stream];
432 			char *audio_buf = NULL;
433 			int c, n, sz = 0;
434 
435 			if (sub && !cdev->input_panic) {
436 				struct snd_pcm_runtime *rt = sub->runtime;
437 				audio_buf = rt->dma_area;
438 				sz = frames_to_bytes(rt, rt->buffer_size);
439 			}
440 
441 			for (c = 0; c < CHANNELS_PER_STREAM; c++) {
442 				/* 3 audio data bytes, followed by 1 check byte */
443 				if (audio_buf) {
444 					for (n = 0; n < BYTES_PER_SAMPLE; n++) {
445 						audio_buf[cdev->audio_in_buf_pos[stream]++] = usb_buf[i+n];
446 
447 						if (cdev->audio_in_buf_pos[stream] == sz)
448 							cdev->audio_in_buf_pos[stream] = 0;
449 					}
450 
451 					cdev->period_in_count[stream] += BYTES_PER_SAMPLE;
452 				}
453 
454 				i += BYTES_PER_SAMPLE;
455 
456 				if (usb_buf[i] != ((stream << 1) | c) &&
457 				    !cdev->first_packet) {
458 					if (!cdev->input_panic)
459 						dev_warn(dev, " EXPECTED: %02x got %02x, c %d, stream %d, i %d\n",
460 							 ((stream << 1) | c), usb_buf[i], c, stream, i);
461 					cdev->input_panic = 1;
462 				}
463 
464 				i++;
465 			}
466 		}
467 	}
468 
469 	if (cdev->first_packet > 0)
470 		cdev->first_packet--;
471 }
472 
473 static void read_in_urb(struct snd_usb_caiaqdev *cdev,
474 			const struct urb *urb,
475 			const struct usb_iso_packet_descriptor *iso)
476 {
477 	struct device *dev = caiaqdev_to_dev(cdev);
478 
479 	if (!cdev->streaming)
480 		return;
481 
482 	if (iso->actual_length < cdev->bpp)
483 		return;
484 
485 	switch (cdev->spec.data_alignment) {
486 	case 0:
487 		read_in_urb_mode0(cdev, urb, iso);
488 		break;
489 	case 2:
490 		read_in_urb_mode2(cdev, urb, iso);
491 		break;
492 	case 3:
493 		read_in_urb_mode3(cdev, urb, iso);
494 		break;
495 	}
496 
497 	if ((cdev->input_panic || cdev->output_panic) && !cdev->warned) {
498 		dev_warn(dev, "streaming error detected %s %s\n",
499 				cdev->input_panic ? "(input)" : "",
500 				cdev->output_panic ? "(output)" : "");
501 		cdev->warned = 1;
502 	}
503 }
504 
505 static void fill_out_urb_mode_0(struct snd_usb_caiaqdev *cdev,
506 				struct urb *urb,
507 				const struct usb_iso_packet_descriptor *iso)
508 {
509 	unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
510 	struct snd_pcm_substream *sub;
511 	int stream, i;
512 
513 	for (i = 0; i < iso->length;) {
514 		for (stream = 0; stream < cdev->n_streams; stream++, i++) {
515 			sub = cdev->sub_playback[stream];
516 			if (sub) {
517 				struct snd_pcm_runtime *rt = sub->runtime;
518 				char *audio_buf = rt->dma_area;
519 				int sz = frames_to_bytes(rt, rt->buffer_size);
520 				usb_buf[i] =
521 					audio_buf[cdev->audio_out_buf_pos[stream]];
522 				cdev->period_out_count[stream]++;
523 				cdev->audio_out_buf_pos[stream]++;
524 				if (cdev->audio_out_buf_pos[stream] == sz)
525 					cdev->audio_out_buf_pos[stream] = 0;
526 			} else
527 				usb_buf[i] = 0;
528 		}
529 
530 		/* fill in the check bytes */
531 		if (cdev->spec.data_alignment == 2 &&
532 		    i % (cdev->n_streams * BYTES_PER_SAMPLE_USB) ==
533 		        (cdev->n_streams * CHANNELS_PER_STREAM))
534 			for (stream = 0; stream < cdev->n_streams; stream++, i++)
535 				usb_buf[i] = MAKE_CHECKBYTE(cdev, stream, i);
536 	}
537 }
538 
539 static void fill_out_urb_mode_3(struct snd_usb_caiaqdev *cdev,
540 				struct urb *urb,
541 				const struct usb_iso_packet_descriptor *iso)
542 {
543 	unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
544 	int stream, i;
545 
546 	for (i = 0; i < iso->length;) {
547 		for (stream = 0; stream < cdev->n_streams; stream++) {
548 			struct snd_pcm_substream *sub = cdev->sub_playback[stream];
549 			char *audio_buf = NULL;
550 			int c, n, sz = 0;
551 
552 			if (sub) {
553 				struct snd_pcm_runtime *rt = sub->runtime;
554 				audio_buf = rt->dma_area;
555 				sz = frames_to_bytes(rt, rt->buffer_size);
556 			}
557 
558 			for (c = 0; c < CHANNELS_PER_STREAM; c++) {
559 				for (n = 0; n < BYTES_PER_SAMPLE; n++) {
560 					if (audio_buf) {
561 						usb_buf[i+n] = audio_buf[cdev->audio_out_buf_pos[stream]++];
562 
563 						if (cdev->audio_out_buf_pos[stream] == sz)
564 							cdev->audio_out_buf_pos[stream] = 0;
565 					} else {
566 						usb_buf[i+n] = 0;
567 					}
568 				}
569 
570 				if (audio_buf)
571 					cdev->period_out_count[stream] += BYTES_PER_SAMPLE;
572 
573 				i += BYTES_PER_SAMPLE;
574 
575 				/* fill in the check byte pattern */
576 				usb_buf[i++] = (stream << 1) | c;
577 			}
578 		}
579 	}
580 }
581 
582 static inline void fill_out_urb(struct snd_usb_caiaqdev *cdev,
583 				struct urb *urb,
584 				const struct usb_iso_packet_descriptor *iso)
585 {
586 	switch (cdev->spec.data_alignment) {
587 	case 0:
588 	case 2:
589 		fill_out_urb_mode_0(cdev, urb, iso);
590 		break;
591 	case 3:
592 		fill_out_urb_mode_3(cdev, urb, iso);
593 		break;
594 	}
595 }
596 
597 static void read_completed(struct urb *urb)
598 {
599 	struct snd_usb_caiaq_cb_info *info = urb->context;
600 	struct snd_usb_caiaqdev *cdev;
601 	struct device *dev;
602 	struct urb *out = NULL;
603 	int i, frame, len, send_it = 0, outframe = 0;
604 	unsigned long flags;
605 	size_t offset = 0;
606 
607 	if (urb->status || !info)
608 		return;
609 
610 	cdev = info->cdev;
611 	dev = caiaqdev_to_dev(cdev);
612 
613 	if (!cdev->streaming)
614 		return;
615 
616 	/* find an unused output urb that is unused */
617 	for (i = 0; i < N_URBS; i++)
618 		if (test_and_set_bit(i, &cdev->outurb_active_mask) == 0) {
619 			out = cdev->data_urbs_out[i];
620 			break;
621 		}
622 
623 	if (!out) {
624 		dev_err(dev, "Unable to find an output urb to use\n");
625 		goto requeue;
626 	}
627 
628 	/* read the recently received packet and send back one which has
629 	 * the same layout */
630 	for (frame = 0; frame < FRAMES_PER_URB; frame++) {
631 		if (urb->iso_frame_desc[frame].status)
632 			continue;
633 
634 		len = urb->iso_frame_desc[outframe].actual_length;
635 		out->iso_frame_desc[outframe].length = len;
636 		out->iso_frame_desc[outframe].actual_length = 0;
637 		out->iso_frame_desc[outframe].offset = offset;
638 		offset += len;
639 
640 		if (len > 0) {
641 			spin_lock_irqsave(&cdev->spinlock, flags);
642 			fill_out_urb(cdev, out, &out->iso_frame_desc[outframe]);
643 			read_in_urb(cdev, urb, &urb->iso_frame_desc[frame]);
644 			spin_unlock_irqrestore(&cdev->spinlock, flags);
645 			check_for_elapsed_periods(cdev, cdev->sub_playback);
646 			check_for_elapsed_periods(cdev, cdev->sub_capture);
647 			send_it = 1;
648 		}
649 
650 		outframe++;
651 	}
652 
653 	if (send_it) {
654 		out->number_of_packets = outframe;
655 		usb_submit_urb(out, GFP_ATOMIC);
656 	} else {
657 		struct snd_usb_caiaq_cb_info *oinfo = out->context;
658 		clear_bit(oinfo->index, &cdev->outurb_active_mask);
659 	}
660 
661 requeue:
662 	/* re-submit inbound urb */
663 	for (frame = 0; frame < FRAMES_PER_URB; frame++) {
664 		urb->iso_frame_desc[frame].offset = BYTES_PER_FRAME * frame;
665 		urb->iso_frame_desc[frame].length = BYTES_PER_FRAME;
666 		urb->iso_frame_desc[frame].actual_length = 0;
667 	}
668 
669 	urb->number_of_packets = FRAMES_PER_URB;
670 	usb_submit_urb(urb, GFP_ATOMIC);
671 }
672 
673 static void write_completed(struct urb *urb)
674 {
675 	struct snd_usb_caiaq_cb_info *info = urb->context;
676 	struct snd_usb_caiaqdev *cdev = info->cdev;
677 
678 	if (!cdev->output_running) {
679 		cdev->output_running = 1;
680 		wake_up(&cdev->prepare_wait_queue);
681 	}
682 
683 	clear_bit(info->index, &cdev->outurb_active_mask);
684 }
685 
686 static struct urb **alloc_urbs(struct snd_usb_caiaqdev *cdev, int dir, int *ret)
687 {
688 	int i, frame;
689 	struct urb **urbs;
690 	struct usb_device *usb_dev = cdev->chip.dev;
691 	unsigned int pipe;
692 
693 	pipe = (dir == SNDRV_PCM_STREAM_PLAYBACK) ?
694 		usb_sndisocpipe(usb_dev, ENDPOINT_PLAYBACK) :
695 		usb_rcvisocpipe(usb_dev, ENDPOINT_CAPTURE);
696 
697 	urbs = kmalloc_array(N_URBS, sizeof(*urbs), GFP_KERNEL);
698 	if (!urbs) {
699 		*ret = -ENOMEM;
700 		return NULL;
701 	}
702 
703 	for (i = 0; i < N_URBS; i++) {
704 		urbs[i] = usb_alloc_urb(FRAMES_PER_URB, GFP_KERNEL);
705 		if (!urbs[i]) {
706 			*ret = -ENOMEM;
707 			return urbs;
708 		}
709 
710 		urbs[i]->transfer_buffer =
711 			kmalloc_array(BYTES_PER_FRAME, FRAMES_PER_URB,
712 				      GFP_KERNEL);
713 		if (!urbs[i]->transfer_buffer) {
714 			*ret = -ENOMEM;
715 			return urbs;
716 		}
717 
718 		for (frame = 0; frame < FRAMES_PER_URB; frame++) {
719 			struct usb_iso_packet_descriptor *iso =
720 				&urbs[i]->iso_frame_desc[frame];
721 
722 			iso->offset = BYTES_PER_FRAME * frame;
723 			iso->length = BYTES_PER_FRAME;
724 		}
725 
726 		urbs[i]->dev = usb_dev;
727 		urbs[i]->pipe = pipe;
728 		urbs[i]->transfer_buffer_length = FRAMES_PER_URB
729 						* BYTES_PER_FRAME;
730 		urbs[i]->context = &cdev->data_cb_info[i];
731 		urbs[i]->interval = 1;
732 		urbs[i]->number_of_packets = FRAMES_PER_URB;
733 		urbs[i]->complete = (dir == SNDRV_PCM_STREAM_CAPTURE) ?
734 					read_completed : write_completed;
735 	}
736 
737 	*ret = 0;
738 	return urbs;
739 }
740 
741 static void free_urbs(struct urb **urbs)
742 {
743 	int i;
744 
745 	if (!urbs)
746 		return;
747 
748 	for (i = 0; i < N_URBS; i++) {
749 		if (!urbs[i])
750 			continue;
751 
752 		usb_kill_urb(urbs[i]);
753 		kfree(urbs[i]->transfer_buffer);
754 		usb_free_urb(urbs[i]);
755 	}
756 
757 	kfree(urbs);
758 }
759 
760 int snd_usb_caiaq_audio_init(struct snd_usb_caiaqdev *cdev)
761 {
762 	int i, ret;
763 	struct device *dev = caiaqdev_to_dev(cdev);
764 
765 	cdev->n_audio_in  = max(cdev->spec.num_analog_audio_in,
766 			       cdev->spec.num_digital_audio_in) /
767 				CHANNELS_PER_STREAM;
768 	cdev->n_audio_out = max(cdev->spec.num_analog_audio_out,
769 			       cdev->spec.num_digital_audio_out) /
770 				CHANNELS_PER_STREAM;
771 	cdev->n_streams = max(cdev->n_audio_in, cdev->n_audio_out);
772 
773 	dev_dbg(dev, "cdev->n_audio_in = %d\n", cdev->n_audio_in);
774 	dev_dbg(dev, "cdev->n_audio_out = %d\n", cdev->n_audio_out);
775 	dev_dbg(dev, "cdev->n_streams = %d\n", cdev->n_streams);
776 
777 	if (cdev->n_streams > MAX_STREAMS) {
778 		dev_err(dev, "unable to initialize device, too many streams.\n");
779 		return -EINVAL;
780 	}
781 
782 	if (cdev->n_streams < 1) {
783 		dev_err(dev, "bogus number of streams: %d\n", cdev->n_streams);
784 		return -EINVAL;
785 	}
786 
787 	ret = snd_pcm_new(cdev->chip.card, cdev->product_name, 0,
788 			cdev->n_audio_out, cdev->n_audio_in, &cdev->pcm);
789 
790 	if (ret < 0) {
791 		dev_err(dev, "snd_pcm_new() returned %d\n", ret);
792 		return ret;
793 	}
794 
795 	cdev->pcm->private_data = cdev;
796 	strscpy(cdev->pcm->name, cdev->product_name, sizeof(cdev->pcm->name));
797 
798 	memset(cdev->sub_playback, 0, sizeof(cdev->sub_playback));
799 	memset(cdev->sub_capture, 0, sizeof(cdev->sub_capture));
800 
801 	memcpy(&cdev->pcm_info, &snd_usb_caiaq_pcm_hardware,
802 			sizeof(snd_usb_caiaq_pcm_hardware));
803 
804 	/* setup samplerates */
805 	cdev->samplerates = cdev->pcm_info.rates;
806 	switch (cdev->chip.usb_id) {
807 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_AK1):
808 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_RIGKONTROL3):
809 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_SESSIONIO):
810 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_GUITARRIGMOBILE):
811 		cdev->samplerates |= SNDRV_PCM_RATE_192000;
812 		fallthrough;
813 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_AUDIO2DJ):
814 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_AUDIO4DJ):
815 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_AUDIO8DJ):
816 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_TRAKTORAUDIO2):
817 		cdev->samplerates |= SNDRV_PCM_RATE_88200;
818 		break;
819 	}
820 
821 	snd_pcm_set_ops(cdev->pcm, SNDRV_PCM_STREAM_PLAYBACK,
822 				&snd_usb_caiaq_ops);
823 	snd_pcm_set_ops(cdev->pcm, SNDRV_PCM_STREAM_CAPTURE,
824 				&snd_usb_caiaq_ops);
825 	snd_pcm_set_managed_buffer_all(cdev->pcm, SNDRV_DMA_TYPE_VMALLOC,
826 				       NULL, 0, 0);
827 
828 	cdev->data_cb_info =
829 		kmalloc_array(N_URBS, sizeof(struct snd_usb_caiaq_cb_info),
830 					GFP_KERNEL);
831 
832 	if (!cdev->data_cb_info)
833 		return -ENOMEM;
834 
835 	cdev->outurb_active_mask = 0;
836 	BUILD_BUG_ON(N_URBS > (sizeof(cdev->outurb_active_mask) * 8));
837 
838 	for (i = 0; i < N_URBS; i++) {
839 		cdev->data_cb_info[i].cdev = cdev;
840 		cdev->data_cb_info[i].index = i;
841 	}
842 
843 	cdev->data_urbs_in = alloc_urbs(cdev, SNDRV_PCM_STREAM_CAPTURE, &ret);
844 	if (ret < 0) {
845 		kfree(cdev->data_cb_info);
846 		free_urbs(cdev->data_urbs_in);
847 		return ret;
848 	}
849 
850 	cdev->data_urbs_out = alloc_urbs(cdev, SNDRV_PCM_STREAM_PLAYBACK, &ret);
851 	if (ret < 0) {
852 		kfree(cdev->data_cb_info);
853 		free_urbs(cdev->data_urbs_in);
854 		free_urbs(cdev->data_urbs_out);
855 		return ret;
856 	}
857 
858 	return 0;
859 }
860 
861 void snd_usb_caiaq_audio_disconnect(struct snd_usb_caiaqdev *cdev)
862 {
863 	struct device *dev = caiaqdev_to_dev(cdev);
864 
865 	dev_dbg(dev, "%s(%p)\n", __func__, cdev);
866 	stream_stop(cdev);
867 }
868 
869 void snd_usb_caiaq_audio_free(struct snd_usb_caiaqdev *cdev)
870 {
871 	struct device *dev = caiaqdev_to_dev(cdev);
872 
873 	dev_dbg(dev, "%s(%p)\n", __func__, cdev);
874 	free_urbs(cdev->data_urbs_in);
875 	free_urbs(cdev->data_urbs_out);
876 	kfree(cdev->data_cb_info);
877 }
878