xref: /openbmc/linux/sound/usb/caiaq/audio.c (revision 95c96174)
1 /*
2  *   Copyright (c) 2006-2008 Daniel Mack, Karsten Wiese
3  *
4  *   This program is free software; you can redistribute it and/or modify
5  *   it under the terms of the GNU General Public License as published by
6  *   the Free Software Foundation; either version 2 of the License, or
7  *   (at your option) any later version.
8  *
9  *   This program is distributed in the hope that it will be useful,
10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  *   GNU General Public License for more details.
13  *
14  *   You should have received a copy of the GNU General Public License
15  *   along with this program; if not, write to the Free Software
16  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
17 */
18 
19 #include <linux/spinlock.h>
20 #include <linux/slab.h>
21 #include <linux/init.h>
22 #include <linux/usb.h>
23 #include <sound/core.h>
24 #include <sound/pcm.h>
25 
26 #include "device.h"
27 #include "audio.h"
28 
29 #define N_URBS			32
30 #define CLOCK_DRIFT_TOLERANCE	5
31 #define FRAMES_PER_URB		8
32 #define BYTES_PER_FRAME		512
33 #define CHANNELS_PER_STREAM	2
34 #define BYTES_PER_SAMPLE	3
35 #define BYTES_PER_SAMPLE_USB	4
36 #define MAX_BUFFER_SIZE		(128*1024)
37 #define MAX_ENDPOINT_SIZE	512
38 
39 #define ENDPOINT_CAPTURE	2
40 #define ENDPOINT_PLAYBACK	6
41 
42 #define MAKE_CHECKBYTE(dev,stream,i) \
43 	(stream << 1) | (~(i / (dev->n_streams * BYTES_PER_SAMPLE_USB)) & 1)
44 
45 static struct snd_pcm_hardware snd_usb_caiaq_pcm_hardware = {
46 	.info 		= (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
47 			   SNDRV_PCM_INFO_BLOCK_TRANSFER),
48 	.formats 	= SNDRV_PCM_FMTBIT_S24_3BE,
49 	.rates 		= (SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000 |
50 			   SNDRV_PCM_RATE_96000),
51 	.rate_min	= 44100,
52 	.rate_max	= 0, /* will overwrite later */
53 	.channels_min	= CHANNELS_PER_STREAM,
54 	.channels_max	= CHANNELS_PER_STREAM,
55 	.buffer_bytes_max = MAX_BUFFER_SIZE,
56 	.period_bytes_min = 128,
57 	.period_bytes_max = MAX_BUFFER_SIZE,
58 	.periods_min	= 1,
59 	.periods_max	= 1024,
60 };
61 
62 static void
63 activate_substream(struct snd_usb_caiaqdev *dev,
64 	           struct snd_pcm_substream *sub)
65 {
66 	spin_lock(&dev->spinlock);
67 
68 	if (sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
69 		dev->sub_playback[sub->number] = sub;
70 	else
71 		dev->sub_capture[sub->number] = sub;
72 
73 	spin_unlock(&dev->spinlock);
74 }
75 
76 static void
77 deactivate_substream(struct snd_usb_caiaqdev *dev,
78 		     struct snd_pcm_substream *sub)
79 {
80 	unsigned long flags;
81 	spin_lock_irqsave(&dev->spinlock, flags);
82 
83 	if (sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
84 		dev->sub_playback[sub->number] = NULL;
85 	else
86 		dev->sub_capture[sub->number] = NULL;
87 
88 	spin_unlock_irqrestore(&dev->spinlock, flags);
89 }
90 
91 static int
92 all_substreams_zero(struct snd_pcm_substream **subs)
93 {
94 	int i;
95 	for (i = 0; i < MAX_STREAMS; i++)
96 		if (subs[i] != NULL)
97 			return 0;
98 	return 1;
99 }
100 
101 static int stream_start(struct snd_usb_caiaqdev *dev)
102 {
103 	int i, ret;
104 
105 	debug("%s(%p)\n", __func__, dev);
106 
107 	if (dev->streaming)
108 		return -EINVAL;
109 
110 	memset(dev->sub_playback, 0, sizeof(dev->sub_playback));
111 	memset(dev->sub_capture, 0, sizeof(dev->sub_capture));
112 	dev->input_panic = 0;
113 	dev->output_panic = 0;
114 	dev->first_packet = 4;
115 	dev->streaming = 1;
116 	dev->warned = 0;
117 
118 	for (i = 0; i < N_URBS; i++) {
119 		ret = usb_submit_urb(dev->data_urbs_in[i], GFP_ATOMIC);
120 		if (ret) {
121 			log("unable to trigger read #%d! (ret %d)\n", i, ret);
122 			dev->streaming = 0;
123 			return -EPIPE;
124 		}
125 	}
126 
127 	return 0;
128 }
129 
130 static void stream_stop(struct snd_usb_caiaqdev *dev)
131 {
132 	int i;
133 
134 	debug("%s(%p)\n", __func__, dev);
135 	if (!dev->streaming)
136 		return;
137 
138 	dev->streaming = 0;
139 
140 	for (i = 0; i < N_URBS; i++) {
141 		usb_kill_urb(dev->data_urbs_in[i]);
142 
143 		if (test_bit(i, &dev->outurb_active_mask))
144 			usb_kill_urb(dev->data_urbs_out[i]);
145 	}
146 
147 	dev->outurb_active_mask = 0;
148 }
149 
150 static int snd_usb_caiaq_substream_open(struct snd_pcm_substream *substream)
151 {
152 	struct snd_usb_caiaqdev *dev = snd_pcm_substream_chip(substream);
153 	debug("%s(%p)\n", __func__, substream);
154 	substream->runtime->hw = dev->pcm_info;
155 	snd_pcm_limit_hw_rates(substream->runtime);
156 	return 0;
157 }
158 
159 static int snd_usb_caiaq_substream_close(struct snd_pcm_substream *substream)
160 {
161 	struct snd_usb_caiaqdev *dev = snd_pcm_substream_chip(substream);
162 
163 	debug("%s(%p)\n", __func__, substream);
164 	if (all_substreams_zero(dev->sub_playback) &&
165 	    all_substreams_zero(dev->sub_capture)) {
166 		/* when the last client has stopped streaming,
167 		 * all sample rates are allowed again */
168 		stream_stop(dev);
169 		dev->pcm_info.rates = dev->samplerates;
170 	}
171 
172 	return 0;
173 }
174 
175 static int snd_usb_caiaq_pcm_hw_params(struct snd_pcm_substream *sub,
176 				       struct snd_pcm_hw_params *hw_params)
177 {
178 	debug("%s(%p)\n", __func__, sub);
179 	return snd_pcm_lib_malloc_pages(sub, params_buffer_bytes(hw_params));
180 }
181 
182 static int snd_usb_caiaq_pcm_hw_free(struct snd_pcm_substream *sub)
183 {
184 	struct snd_usb_caiaqdev *dev = snd_pcm_substream_chip(sub);
185 	debug("%s(%p)\n", __func__, sub);
186 	deactivate_substream(dev, sub);
187 	return snd_pcm_lib_free_pages(sub);
188 }
189 
190 /* this should probably go upstream */
191 #if SNDRV_PCM_RATE_5512 != 1 << 0 || SNDRV_PCM_RATE_192000 != 1 << 12
192 #error "Change this table"
193 #endif
194 
195 static unsigned int rates[] = { 5512, 8000, 11025, 16000, 22050, 32000, 44100,
196 				48000, 64000, 88200, 96000, 176400, 192000 };
197 
198 static int snd_usb_caiaq_pcm_prepare(struct snd_pcm_substream *substream)
199 {
200 	int bytes_per_sample, bpp, ret, i;
201 	int index = substream->number;
202 	struct snd_usb_caiaqdev *dev = snd_pcm_substream_chip(substream);
203 	struct snd_pcm_runtime *runtime = substream->runtime;
204 
205 	debug("%s(%p)\n", __func__, substream);
206 
207 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
208 		int out_pos;
209 
210 		switch (dev->spec.data_alignment) {
211 		case 0:
212 		case 2:
213 			out_pos = BYTES_PER_SAMPLE + 1;
214 			break;
215 		case 3:
216 		default:
217 			out_pos = 0;
218 			break;
219 		}
220 
221 		dev->period_out_count[index] = out_pos;
222 		dev->audio_out_buf_pos[index] = out_pos;
223 	} else {
224 		int in_pos;
225 
226 		switch (dev->spec.data_alignment) {
227 		case 0:
228 			in_pos = BYTES_PER_SAMPLE + 2;
229 			break;
230 		case 2:
231 			in_pos = BYTES_PER_SAMPLE;
232 			break;
233 		case 3:
234 		default:
235 			in_pos = 0;
236 			break;
237 		}
238 
239 		dev->period_in_count[index] = in_pos;
240 		dev->audio_in_buf_pos[index] = in_pos;
241 	}
242 
243 	if (dev->streaming)
244 		return 0;
245 
246 	/* the first client that opens a stream defines the sample rate
247 	 * setting for all subsequent calls, until the last client closed. */
248 	for (i=0; i < ARRAY_SIZE(rates); i++)
249 		if (runtime->rate == rates[i])
250 			dev->pcm_info.rates = 1 << i;
251 
252 	snd_pcm_limit_hw_rates(runtime);
253 
254 	bytes_per_sample = BYTES_PER_SAMPLE;
255 	if (dev->spec.data_alignment >= 2)
256 		bytes_per_sample++;
257 
258 	bpp = ((runtime->rate / 8000) + CLOCK_DRIFT_TOLERANCE)
259 		* bytes_per_sample * CHANNELS_PER_STREAM * dev->n_streams;
260 
261 	if (bpp > MAX_ENDPOINT_SIZE)
262 		bpp = MAX_ENDPOINT_SIZE;
263 
264 	ret = snd_usb_caiaq_set_audio_params(dev, runtime->rate,
265 					     runtime->sample_bits, bpp);
266 	if (ret)
267 		return ret;
268 
269 	ret = stream_start(dev);
270 	if (ret)
271 		return ret;
272 
273 	dev->output_running = 0;
274 	wait_event_timeout(dev->prepare_wait_queue, dev->output_running, HZ);
275 	if (!dev->output_running) {
276 		stream_stop(dev);
277 		return -EPIPE;
278 	}
279 
280 	return 0;
281 }
282 
283 static int snd_usb_caiaq_pcm_trigger(struct snd_pcm_substream *sub, int cmd)
284 {
285 	struct snd_usb_caiaqdev *dev = snd_pcm_substream_chip(sub);
286 
287 	debug("%s(%p) cmd %d\n", __func__, sub, cmd);
288 
289 	switch (cmd) {
290 	case SNDRV_PCM_TRIGGER_START:
291 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
292 		activate_substream(dev, sub);
293 		break;
294 	case SNDRV_PCM_TRIGGER_STOP:
295 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
296 		deactivate_substream(dev, sub);
297 		break;
298 	default:
299 		return -EINVAL;
300 	}
301 
302 	return 0;
303 }
304 
305 static snd_pcm_uframes_t
306 snd_usb_caiaq_pcm_pointer(struct snd_pcm_substream *sub)
307 {
308 	int index = sub->number;
309 	struct snd_usb_caiaqdev *dev = snd_pcm_substream_chip(sub);
310 	snd_pcm_uframes_t ptr;
311 
312 	spin_lock(&dev->spinlock);
313 
314 	if (dev->input_panic || dev->output_panic) {
315 		ptr = SNDRV_PCM_POS_XRUN;
316 		goto unlock;
317 	}
318 
319 	if (sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
320 		ptr = bytes_to_frames(sub->runtime,
321 					dev->audio_out_buf_pos[index]);
322 	else
323 		ptr = bytes_to_frames(sub->runtime,
324 					dev->audio_in_buf_pos[index]);
325 
326 unlock:
327 	spin_unlock(&dev->spinlock);
328 	return ptr;
329 }
330 
331 /* operators for both playback and capture */
332 static struct snd_pcm_ops snd_usb_caiaq_ops = {
333 	.open =		snd_usb_caiaq_substream_open,
334 	.close =	snd_usb_caiaq_substream_close,
335 	.ioctl =	snd_pcm_lib_ioctl,
336 	.hw_params =	snd_usb_caiaq_pcm_hw_params,
337 	.hw_free =	snd_usb_caiaq_pcm_hw_free,
338 	.prepare =	snd_usb_caiaq_pcm_prepare,
339 	.trigger =	snd_usb_caiaq_pcm_trigger,
340 	.pointer =	snd_usb_caiaq_pcm_pointer
341 };
342 
343 static void check_for_elapsed_periods(struct snd_usb_caiaqdev *dev,
344 				      struct snd_pcm_substream **subs)
345 {
346 	int stream, pb, *cnt;
347 	struct snd_pcm_substream *sub;
348 
349 	for (stream = 0; stream < dev->n_streams; stream++) {
350 		sub = subs[stream];
351 		if (!sub)
352 			continue;
353 
354 		pb = snd_pcm_lib_period_bytes(sub);
355 		cnt = (sub->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
356 					&dev->period_out_count[stream] :
357 					&dev->period_in_count[stream];
358 
359 		if (*cnt >= pb) {
360 			snd_pcm_period_elapsed(sub);
361 			*cnt %= pb;
362 		}
363 	}
364 }
365 
366 static void read_in_urb_mode0(struct snd_usb_caiaqdev *dev,
367 			      const struct urb *urb,
368 			      const struct usb_iso_packet_descriptor *iso)
369 {
370 	unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
371 	struct snd_pcm_substream *sub;
372 	int stream, i;
373 
374 	if (all_substreams_zero(dev->sub_capture))
375 		return;
376 
377 	for (i = 0; i < iso->actual_length;) {
378 		for (stream = 0; stream < dev->n_streams; stream++, i++) {
379 			sub = dev->sub_capture[stream];
380 			if (sub) {
381 				struct snd_pcm_runtime *rt = sub->runtime;
382 				char *audio_buf = rt->dma_area;
383 				int sz = frames_to_bytes(rt, rt->buffer_size);
384 				audio_buf[dev->audio_in_buf_pos[stream]++]
385 					= usb_buf[i];
386 				dev->period_in_count[stream]++;
387 				if (dev->audio_in_buf_pos[stream] == sz)
388 					dev->audio_in_buf_pos[stream] = 0;
389 			}
390 		}
391 	}
392 }
393 
394 static void read_in_urb_mode2(struct snd_usb_caiaqdev *dev,
395 			      const struct urb *urb,
396 			      const struct usb_iso_packet_descriptor *iso)
397 {
398 	unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
399 	unsigned char check_byte;
400 	struct snd_pcm_substream *sub;
401 	int stream, i;
402 
403 	for (i = 0; i < iso->actual_length;) {
404 		if (i % (dev->n_streams * BYTES_PER_SAMPLE_USB) == 0) {
405 			for (stream = 0;
406 			     stream < dev->n_streams;
407 			     stream++, i++) {
408 				if (dev->first_packet)
409 					continue;
410 
411 				check_byte = MAKE_CHECKBYTE(dev, stream, i);
412 
413 				if ((usb_buf[i] & 0x3f) != check_byte)
414 					dev->input_panic = 1;
415 
416 				if (usb_buf[i] & 0x80)
417 					dev->output_panic = 1;
418 			}
419 		}
420 		dev->first_packet = 0;
421 
422 		for (stream = 0; stream < dev->n_streams; stream++, i++) {
423 			sub = dev->sub_capture[stream];
424 			if (dev->input_panic)
425 				usb_buf[i] = 0;
426 
427 			if (sub) {
428 				struct snd_pcm_runtime *rt = sub->runtime;
429 				char *audio_buf = rt->dma_area;
430 				int sz = frames_to_bytes(rt, rt->buffer_size);
431 				audio_buf[dev->audio_in_buf_pos[stream]++] =
432 					usb_buf[i];
433 				dev->period_in_count[stream]++;
434 				if (dev->audio_in_buf_pos[stream] == sz)
435 					dev->audio_in_buf_pos[stream] = 0;
436 			}
437 		}
438 	}
439 }
440 
441 static void read_in_urb_mode3(struct snd_usb_caiaqdev *dev,
442 			      const struct urb *urb,
443 			      const struct usb_iso_packet_descriptor *iso)
444 {
445 	unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
446 	int stream, i;
447 
448 	/* paranoia check */
449 	if (iso->actual_length % (BYTES_PER_SAMPLE_USB * CHANNELS_PER_STREAM))
450 		return;
451 
452 	for (i = 0; i < iso->actual_length;) {
453 		for (stream = 0; stream < dev->n_streams; stream++) {
454 			struct snd_pcm_substream *sub = dev->sub_capture[stream];
455 			char *audio_buf = NULL;
456 			int c, n, sz = 0;
457 
458 			if (sub && !dev->input_panic) {
459 				struct snd_pcm_runtime *rt = sub->runtime;
460 				audio_buf = rt->dma_area;
461 				sz = frames_to_bytes(rt, rt->buffer_size);
462 			}
463 
464 			for (c = 0; c < CHANNELS_PER_STREAM; c++) {
465 				/* 3 audio data bytes, followed by 1 check byte */
466 				if (audio_buf) {
467 					for (n = 0; n < BYTES_PER_SAMPLE; n++) {
468 						audio_buf[dev->audio_in_buf_pos[stream]++] = usb_buf[i+n];
469 
470 						if (dev->audio_in_buf_pos[stream] == sz)
471 							dev->audio_in_buf_pos[stream] = 0;
472 					}
473 
474 					dev->period_in_count[stream] += BYTES_PER_SAMPLE;
475 				}
476 
477 				i += BYTES_PER_SAMPLE;
478 
479 				if (usb_buf[i] != ((stream << 1) | c) &&
480 				    !dev->first_packet) {
481 					if (!dev->input_panic)
482 						printk(" EXPECTED: %02x got %02x, c %d, stream %d, i %d\n",
483 							((stream << 1) | c), usb_buf[i], c, stream, i);
484 					dev->input_panic = 1;
485 				}
486 
487 				i++;
488 			}
489 		}
490 	}
491 
492 	if (dev->first_packet > 0)
493 		dev->first_packet--;
494 }
495 
496 static void read_in_urb(struct snd_usb_caiaqdev *dev,
497 			const struct urb *urb,
498 			const struct usb_iso_packet_descriptor *iso)
499 {
500 	if (!dev->streaming)
501 		return;
502 
503 	if (iso->actual_length < dev->bpp)
504 		return;
505 
506 	switch (dev->spec.data_alignment) {
507 	case 0:
508 		read_in_urb_mode0(dev, urb, iso);
509 		break;
510 	case 2:
511 		read_in_urb_mode2(dev, urb, iso);
512 		break;
513 	case 3:
514 		read_in_urb_mode3(dev, urb, iso);
515 		break;
516 	}
517 
518 	if ((dev->input_panic || dev->output_panic) && !dev->warned) {
519 		debug("streaming error detected %s %s\n",
520 				dev->input_panic ? "(input)" : "",
521 				dev->output_panic ? "(output)" : "");
522 		dev->warned = 1;
523 	}
524 }
525 
526 static void fill_out_urb_mode_0(struct snd_usb_caiaqdev *dev,
527 				struct urb *urb,
528 				const struct usb_iso_packet_descriptor *iso)
529 {
530 	unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
531 	struct snd_pcm_substream *sub;
532 	int stream, i;
533 
534 	for (i = 0; i < iso->length;) {
535 		for (stream = 0; stream < dev->n_streams; stream++, i++) {
536 			sub = dev->sub_playback[stream];
537 			if (sub) {
538 				struct snd_pcm_runtime *rt = sub->runtime;
539 				char *audio_buf = rt->dma_area;
540 				int sz = frames_to_bytes(rt, rt->buffer_size);
541 				usb_buf[i] =
542 					audio_buf[dev->audio_out_buf_pos[stream]];
543 				dev->period_out_count[stream]++;
544 				dev->audio_out_buf_pos[stream]++;
545 				if (dev->audio_out_buf_pos[stream] == sz)
546 					dev->audio_out_buf_pos[stream] = 0;
547 			} else
548 				usb_buf[i] = 0;
549 		}
550 
551 		/* fill in the check bytes */
552 		if (dev->spec.data_alignment == 2 &&
553 		    i % (dev->n_streams * BYTES_PER_SAMPLE_USB) ==
554 		        (dev->n_streams * CHANNELS_PER_STREAM))
555 			for (stream = 0; stream < dev->n_streams; stream++, i++)
556 				usb_buf[i] = MAKE_CHECKBYTE(dev, stream, i);
557 	}
558 }
559 
560 static void fill_out_urb_mode_3(struct snd_usb_caiaqdev *dev,
561 				struct urb *urb,
562 				const struct usb_iso_packet_descriptor *iso)
563 {
564 	unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
565 	int stream, i;
566 
567 	for (i = 0; i < iso->length;) {
568 		for (stream = 0; stream < dev->n_streams; stream++) {
569 			struct snd_pcm_substream *sub = dev->sub_playback[stream];
570 			char *audio_buf = NULL;
571 			int c, n, sz = 0;
572 
573 			if (sub) {
574 				struct snd_pcm_runtime *rt = sub->runtime;
575 				audio_buf = rt->dma_area;
576 				sz = frames_to_bytes(rt, rt->buffer_size);
577 			}
578 
579 			for (c = 0; c < CHANNELS_PER_STREAM; c++) {
580 				for (n = 0; n < BYTES_PER_SAMPLE; n++) {
581 					if (audio_buf) {
582 						usb_buf[i+n] = audio_buf[dev->audio_out_buf_pos[stream]++];
583 
584 						if (dev->audio_out_buf_pos[stream] == sz)
585 							dev->audio_out_buf_pos[stream] = 0;
586 					} else {
587 						usb_buf[i+n] = 0;
588 					}
589 				}
590 
591 				if (audio_buf)
592 					dev->period_out_count[stream] += BYTES_PER_SAMPLE;
593 
594 				i += BYTES_PER_SAMPLE;
595 
596 				/* fill in the check byte pattern */
597 				usb_buf[i++] = (stream << 1) | c;
598 			}
599 		}
600 	}
601 }
602 
603 static inline void fill_out_urb(struct snd_usb_caiaqdev *dev,
604 				struct urb *urb,
605 				const struct usb_iso_packet_descriptor *iso)
606 {
607 	switch (dev->spec.data_alignment) {
608 	case 0:
609 	case 2:
610 		fill_out_urb_mode_0(dev, urb, iso);
611 		break;
612 	case 3:
613 		fill_out_urb_mode_3(dev, urb, iso);
614 		break;
615 	}
616 }
617 
618 static void read_completed(struct urb *urb)
619 {
620 	struct snd_usb_caiaq_cb_info *info = urb->context;
621 	struct snd_usb_caiaqdev *dev;
622 	struct urb *out = NULL;
623 	int i, frame, len, send_it = 0, outframe = 0;
624 	size_t offset = 0;
625 
626 	if (urb->status || !info)
627 		return;
628 
629 	dev = info->dev;
630 
631 	if (!dev->streaming)
632 		return;
633 
634 	/* find an unused output urb that is unused */
635 	for (i = 0; i < N_URBS; i++)
636 		if (test_and_set_bit(i, &dev->outurb_active_mask) == 0) {
637 			out = dev->data_urbs_out[i];
638 			break;
639 		}
640 
641 	if (!out) {
642 		log("Unable to find an output urb to use\n");
643 		goto requeue;
644 	}
645 
646 	/* read the recently received packet and send back one which has
647 	 * the same layout */
648 	for (frame = 0; frame < FRAMES_PER_URB; frame++) {
649 		if (urb->iso_frame_desc[frame].status)
650 			continue;
651 
652 		len = urb->iso_frame_desc[outframe].actual_length;
653 		out->iso_frame_desc[outframe].length = len;
654 		out->iso_frame_desc[outframe].actual_length = 0;
655 		out->iso_frame_desc[outframe].offset = offset;
656 		offset += len;
657 
658 		if (len > 0) {
659 			spin_lock(&dev->spinlock);
660 			fill_out_urb(dev, out, &out->iso_frame_desc[outframe]);
661 			read_in_urb(dev, urb, &urb->iso_frame_desc[frame]);
662 			spin_unlock(&dev->spinlock);
663 			check_for_elapsed_periods(dev, dev->sub_playback);
664 			check_for_elapsed_periods(dev, dev->sub_capture);
665 			send_it = 1;
666 		}
667 
668 		outframe++;
669 	}
670 
671 	if (send_it) {
672 		out->number_of_packets = outframe;
673 		out->transfer_flags = URB_ISO_ASAP;
674 		usb_submit_urb(out, GFP_ATOMIC);
675 	} else {
676 		struct snd_usb_caiaq_cb_info *oinfo = out->context;
677 		clear_bit(oinfo->index, &dev->outurb_active_mask);
678 	}
679 
680 requeue:
681 	/* re-submit inbound urb */
682 	for (frame = 0; frame < FRAMES_PER_URB; frame++) {
683 		urb->iso_frame_desc[frame].offset = BYTES_PER_FRAME * frame;
684 		urb->iso_frame_desc[frame].length = BYTES_PER_FRAME;
685 		urb->iso_frame_desc[frame].actual_length = 0;
686 	}
687 
688 	urb->number_of_packets = FRAMES_PER_URB;
689 	urb->transfer_flags = URB_ISO_ASAP;
690 	usb_submit_urb(urb, GFP_ATOMIC);
691 }
692 
693 static void write_completed(struct urb *urb)
694 {
695 	struct snd_usb_caiaq_cb_info *info = urb->context;
696 	struct snd_usb_caiaqdev *dev = info->dev;
697 
698 	if (!dev->output_running) {
699 		dev->output_running = 1;
700 		wake_up(&dev->prepare_wait_queue);
701 	}
702 
703 	clear_bit(info->index, &dev->outurb_active_mask);
704 }
705 
706 static struct urb **alloc_urbs(struct snd_usb_caiaqdev *dev, int dir, int *ret)
707 {
708 	int i, frame;
709 	struct urb **urbs;
710 	struct usb_device *usb_dev = dev->chip.dev;
711 	unsigned int pipe;
712 
713 	pipe = (dir == SNDRV_PCM_STREAM_PLAYBACK) ?
714 		usb_sndisocpipe(usb_dev, ENDPOINT_PLAYBACK) :
715 		usb_rcvisocpipe(usb_dev, ENDPOINT_CAPTURE);
716 
717 	urbs = kmalloc(N_URBS * sizeof(*urbs), GFP_KERNEL);
718 	if (!urbs) {
719 		log("unable to kmalloc() urbs, OOM!?\n");
720 		*ret = -ENOMEM;
721 		return NULL;
722 	}
723 
724 	for (i = 0; i < N_URBS; i++) {
725 		urbs[i] = usb_alloc_urb(FRAMES_PER_URB, GFP_KERNEL);
726 		if (!urbs[i]) {
727 			log("unable to usb_alloc_urb(), OOM!?\n");
728 			*ret = -ENOMEM;
729 			return urbs;
730 		}
731 
732 		urbs[i]->transfer_buffer =
733 			kmalloc(FRAMES_PER_URB * BYTES_PER_FRAME, GFP_KERNEL);
734 		if (!urbs[i]->transfer_buffer) {
735 			log("unable to kmalloc() transfer buffer, OOM!?\n");
736 			*ret = -ENOMEM;
737 			return urbs;
738 		}
739 
740 		for (frame = 0; frame < FRAMES_PER_URB; frame++) {
741 			struct usb_iso_packet_descriptor *iso =
742 				&urbs[i]->iso_frame_desc[frame];
743 
744 			iso->offset = BYTES_PER_FRAME * frame;
745 			iso->length = BYTES_PER_FRAME;
746 		}
747 
748 		urbs[i]->dev = usb_dev;
749 		urbs[i]->pipe = pipe;
750 		urbs[i]->transfer_buffer_length = FRAMES_PER_URB
751 						* BYTES_PER_FRAME;
752 		urbs[i]->context = &dev->data_cb_info[i];
753 		urbs[i]->interval = 1;
754 		urbs[i]->transfer_flags = URB_ISO_ASAP;
755 		urbs[i]->number_of_packets = FRAMES_PER_URB;
756 		urbs[i]->complete = (dir == SNDRV_PCM_STREAM_CAPTURE) ?
757 					read_completed : write_completed;
758 	}
759 
760 	*ret = 0;
761 	return urbs;
762 }
763 
764 static void free_urbs(struct urb **urbs)
765 {
766 	int i;
767 
768 	if (!urbs)
769 		return;
770 
771 	for (i = 0; i < N_URBS; i++) {
772 		if (!urbs[i])
773 			continue;
774 
775 		usb_kill_urb(urbs[i]);
776 		kfree(urbs[i]->transfer_buffer);
777 		usb_free_urb(urbs[i]);
778 	}
779 
780 	kfree(urbs);
781 }
782 
783 int snd_usb_caiaq_audio_init(struct snd_usb_caiaqdev *dev)
784 {
785 	int i, ret;
786 
787 	dev->n_audio_in  = max(dev->spec.num_analog_audio_in,
788 			       dev->spec.num_digital_audio_in) /
789 				CHANNELS_PER_STREAM;
790 	dev->n_audio_out = max(dev->spec.num_analog_audio_out,
791 			       dev->spec.num_digital_audio_out) /
792 				CHANNELS_PER_STREAM;
793 	dev->n_streams = max(dev->n_audio_in, dev->n_audio_out);
794 
795 	debug("dev->n_audio_in = %d\n", dev->n_audio_in);
796 	debug("dev->n_audio_out = %d\n", dev->n_audio_out);
797 	debug("dev->n_streams = %d\n", dev->n_streams);
798 
799 	if (dev->n_streams > MAX_STREAMS) {
800 		log("unable to initialize device, too many streams.\n");
801 		return -EINVAL;
802 	}
803 
804 	ret = snd_pcm_new(dev->chip.card, dev->product_name, 0,
805 			dev->n_audio_out, dev->n_audio_in, &dev->pcm);
806 
807 	if (ret < 0) {
808 		log("snd_pcm_new() returned %d\n", ret);
809 		return ret;
810 	}
811 
812 	dev->pcm->private_data = dev;
813 	strlcpy(dev->pcm->name, dev->product_name, sizeof(dev->pcm->name));
814 
815 	memset(dev->sub_playback, 0, sizeof(dev->sub_playback));
816 	memset(dev->sub_capture, 0, sizeof(dev->sub_capture));
817 
818 	memcpy(&dev->pcm_info, &snd_usb_caiaq_pcm_hardware,
819 			sizeof(snd_usb_caiaq_pcm_hardware));
820 
821 	/* setup samplerates */
822 	dev->samplerates = dev->pcm_info.rates;
823 	switch (dev->chip.usb_id) {
824 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_AK1):
825 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_RIGKONTROL3):
826 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_SESSIONIO):
827 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_GUITARRIGMOBILE):
828 		dev->samplerates |= SNDRV_PCM_RATE_192000;
829 		/* fall thru */
830 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_AUDIO2DJ):
831 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_AUDIO4DJ):
832 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_AUDIO8DJ):
833 	case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_TRAKTORAUDIO2):
834 		dev->samplerates |= SNDRV_PCM_RATE_88200;
835 		break;
836 	}
837 
838 	snd_pcm_set_ops(dev->pcm, SNDRV_PCM_STREAM_PLAYBACK,
839 				&snd_usb_caiaq_ops);
840 	snd_pcm_set_ops(dev->pcm, SNDRV_PCM_STREAM_CAPTURE,
841 				&snd_usb_caiaq_ops);
842 
843 	snd_pcm_lib_preallocate_pages_for_all(dev->pcm,
844 					SNDRV_DMA_TYPE_CONTINUOUS,
845 					snd_dma_continuous_data(GFP_KERNEL),
846 					MAX_BUFFER_SIZE, MAX_BUFFER_SIZE);
847 
848 	dev->data_cb_info =
849 		kmalloc(sizeof(struct snd_usb_caiaq_cb_info) * N_URBS,
850 					GFP_KERNEL);
851 
852 	if (!dev->data_cb_info)
853 		return -ENOMEM;
854 
855 	dev->outurb_active_mask = 0;
856 	BUILD_BUG_ON(N_URBS > (sizeof(dev->outurb_active_mask) * 8));
857 
858 	for (i = 0; i < N_URBS; i++) {
859 		dev->data_cb_info[i].dev = dev;
860 		dev->data_cb_info[i].index = i;
861 	}
862 
863 	dev->data_urbs_in = alloc_urbs(dev, SNDRV_PCM_STREAM_CAPTURE, &ret);
864 	if (ret < 0) {
865 		kfree(dev->data_cb_info);
866 		free_urbs(dev->data_urbs_in);
867 		return ret;
868 	}
869 
870 	dev->data_urbs_out = alloc_urbs(dev, SNDRV_PCM_STREAM_PLAYBACK, &ret);
871 	if (ret < 0) {
872 		kfree(dev->data_cb_info);
873 		free_urbs(dev->data_urbs_in);
874 		free_urbs(dev->data_urbs_out);
875 		return ret;
876 	}
877 
878 	return 0;
879 }
880 
881 void snd_usb_caiaq_audio_free(struct snd_usb_caiaqdev *dev)
882 {
883 	debug("%s(%p)\n", __func__, dev);
884 	stream_stop(dev);
885 	free_urbs(dev->data_urbs_in);
886 	free_urbs(dev->data_urbs_out);
887 	kfree(dev->data_cb_info);
888 }
889 
890