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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 */
4
5#include <linux/gfp.h>
6#include <linux/init.h>
7#include <linux/ratelimit.h>
8#include <linux/usb.h>
9#include <linux/usb/audio.h>
10#include <linux/slab.h>
11
12#include <sound/core.h>
13#include <sound/pcm.h>
14#include <sound/pcm_params.h>
15
16#include "usbaudio.h"
17#include "helper.h"
18#include "card.h"
19#include "endpoint.h"
20#include "pcm.h"
21#include "quirks.h"
22
23#define EP_FLAG_RUNNING 1
24#define EP_FLAG_STOPPING 2
25
26/*
27 * snd_usb_endpoint is a model that abstracts everything related to an
28 * USB endpoint and its streaming.
29 *
30 * There are functions to activate and deactivate the streaming URBs and
31 * optional callbacks to let the pcm logic handle the actual content of the
32 * packets for playback and record. Thus, the bus streaming and the audio
33 * handlers are fully decoupled.
34 *
35 * There are two different types of endpoints in audio applications.
36 *
37 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
38 * inbound and outbound traffic.
39 *
40 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
41 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
42 * (3 or 4 bytes).
43 *
44 * Each endpoint has to be configured prior to being used by calling
45 * snd_usb_endpoint_set_params().
46 *
47 * The model incorporates a reference counting, so that multiple users
48 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
49 * only the first user will effectively start the URBs, and only the last
50 * one to stop it will tear the URBs down again.
51 */
52
53/*
54 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
55 * this will overflow at approx 524 kHz
56 */
57static inline unsigned get_usb_full_speed_rate(unsigned int rate)
58{
59 return ((rate << 13) + 62) / 125;
60}
61
62/*
63 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
64 * this will overflow at approx 4 MHz
65 */
66static inline unsigned get_usb_high_speed_rate(unsigned int rate)
67{
68 return ((rate << 10) + 62) / 125;
69}
70
71/*
72 * release a urb data
73 */
74static void release_urb_ctx(struct snd_urb_ctx *u)
75{
76 if (u->buffer_size)
77 usb_free_coherent(u->ep->chip->dev, u->buffer_size,
78 u->urb->transfer_buffer,
79 u->urb->transfer_dma);
80 usb_free_urb(u->urb);
81 u->urb = NULL;
82}
83
84static const char *usb_error_string(int err)
85{
86 switch (err) {
87 case -ENODEV:
88 return "no device";
89 case -ENOENT:
90 return "endpoint not enabled";
91 case -EPIPE:
92 return "endpoint stalled";
93 case -ENOSPC:
94 return "not enough bandwidth";
95 case -ESHUTDOWN:
96 return "device disabled";
97 case -EHOSTUNREACH:
98 return "device suspended";
99 case -EINVAL:
100 case -EAGAIN:
101 case -EFBIG:
102 case -EMSGSIZE:
103 return "internal error";
104 default:
105 return "unknown error";
106 }
107}
108
109/**
110 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
111 *
112 * @ep: The snd_usb_endpoint
113 *
114 * Determine whether an endpoint is driven by an implicit feedback
115 * data endpoint source.
116 */
117int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
118{
119 return ep->sync_master &&
120 ep->sync_master->type == SND_USB_ENDPOINT_TYPE_DATA &&
121 ep->type == SND_USB_ENDPOINT_TYPE_DATA &&
122 usb_pipeout(ep->pipe);
123}
124
125/*
126 * For streaming based on information derived from sync endpoints,
127 * prepare_outbound_urb_sizes() will call slave_next_packet_size() to
128 * determine the number of samples to be sent in the next packet.
129 *
130 * For implicit feedback, slave_next_packet_size() is unused.
131 */
132int snd_usb_endpoint_slave_next_packet_size(struct snd_usb_endpoint *ep)
133{
134 unsigned long flags;
135 int ret;
136
137 if (ep->fill_max)
138 return ep->maxframesize;
139
140 spin_lock_irqsave(&ep->lock, flags);
141 ep->phase = (ep->phase & 0xffff)
142 + (ep->freqm << ep->datainterval);
143 ret = min(ep->phase >> 16, ep->maxframesize);
144 spin_unlock_irqrestore(&ep->lock, flags);
145
146 return ret;
147}
148
149/*
150 * For adaptive and synchronous endpoints, prepare_outbound_urb_sizes()
151 * will call next_packet_size() to determine the number of samples to be
152 * sent in the next packet.
153 */
154int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep)
155{
156 int ret;
157
158 if (ep->fill_max)
159 return ep->maxframesize;
160
161 ep->sample_accum += ep->sample_rem;
162 if (ep->sample_accum >= ep->pps) {
163 ep->sample_accum -= ep->pps;
164 ret = ep->packsize[1];
165 } else {
166 ret = ep->packsize[0];
167 }
168
169 return ret;
170}
171
172static void retire_outbound_urb(struct snd_usb_endpoint *ep,
173 struct snd_urb_ctx *urb_ctx)
174{
175 if (ep->retire_data_urb)
176 ep->retire_data_urb(ep->data_subs, urb_ctx->urb);
177}
178
179static void retire_inbound_urb(struct snd_usb_endpoint *ep,
180 struct snd_urb_ctx *urb_ctx)
181{
182 struct urb *urb = urb_ctx->urb;
183
184 if (unlikely(ep->skip_packets > 0)) {
185 ep->skip_packets--;
186 return;
187 }
188
189 if (ep->sync_slave)
190 snd_usb_handle_sync_urb(ep->sync_slave, ep, urb);
191
192 if (ep->retire_data_urb)
193 ep->retire_data_urb(ep->data_subs, urb);
194}
195
196static void prepare_silent_urb(struct snd_usb_endpoint *ep,
197 struct snd_urb_ctx *ctx)
198{
199 struct urb *urb = ctx->urb;
200 unsigned int offs = 0;
201 unsigned int extra = 0;
202 __le32 packet_length;
203 int i;
204
205 /* For tx_length_quirk, put packet length at start of packet */
206 if (ep->chip->tx_length_quirk)
207 extra = sizeof(packet_length);
208
209 for (i = 0; i < ctx->packets; ++i) {
210 unsigned int offset;
211 unsigned int length;
212 int counts;
213
214 if (ctx->packet_size[i])
215 counts = ctx->packet_size[i];
216 else if (ep->sync_master)
217 counts = snd_usb_endpoint_slave_next_packet_size(ep);
218 else
219 counts = snd_usb_endpoint_next_packet_size(ep);
220
221 length = counts * ep->stride; /* number of silent bytes */
222 offset = offs * ep->stride + extra * i;
223 urb->iso_frame_desc[i].offset = offset;
224 urb->iso_frame_desc[i].length = length + extra;
225 if (extra) {
226 packet_length = cpu_to_le32(length);
227 memcpy(urb->transfer_buffer + offset,
228 &packet_length, sizeof(packet_length));
229 }
230 memset(urb->transfer_buffer + offset + extra,
231 ep->silence_value, length);
232 offs += counts;
233 }
234
235 urb->number_of_packets = ctx->packets;
236 urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
237}
238
239/*
240 * Prepare a PLAYBACK urb for submission to the bus.
241 */
242static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
243 struct snd_urb_ctx *ctx)
244{
245 struct urb *urb = ctx->urb;
246 unsigned char *cp = urb->transfer_buffer;
247
248 urb->dev = ep->chip->dev; /* we need to set this at each time */
249
250 switch (ep->type) {
251 case SND_USB_ENDPOINT_TYPE_DATA:
252 if (ep->prepare_data_urb) {
253 ep->prepare_data_urb(ep->data_subs, urb);
254 } else {
255 /* no data provider, so send silence */
256 prepare_silent_urb(ep, ctx);
257 }
258 break;
259
260 case SND_USB_ENDPOINT_TYPE_SYNC:
261 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
262 /*
263 * fill the length and offset of each urb descriptor.
264 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
265 */
266 urb->iso_frame_desc[0].length = 4;
267 urb->iso_frame_desc[0].offset = 0;
268 cp[0] = ep->freqn;
269 cp[1] = ep->freqn >> 8;
270 cp[2] = ep->freqn >> 16;
271 cp[3] = ep->freqn >> 24;
272 } else {
273 /*
274 * fill the length and offset of each urb descriptor.
275 * the fixed 10.14 frequency is passed through the pipe.
276 */
277 urb->iso_frame_desc[0].length = 3;
278 urb->iso_frame_desc[0].offset = 0;
279 cp[0] = ep->freqn >> 2;
280 cp[1] = ep->freqn >> 10;
281 cp[2] = ep->freqn >> 18;
282 }
283
284 break;
285 }
286}
287
288/*
289 * Prepare a CAPTURE or SYNC urb for submission to the bus.
290 */
291static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep,
292 struct snd_urb_ctx *urb_ctx)
293{
294 int i, offs;
295 struct urb *urb = urb_ctx->urb;
296
297 urb->dev = ep->chip->dev; /* we need to set this at each time */
298
299 switch (ep->type) {
300 case SND_USB_ENDPOINT_TYPE_DATA:
301 offs = 0;
302 for (i = 0; i < urb_ctx->packets; i++) {
303 urb->iso_frame_desc[i].offset = offs;
304 urb->iso_frame_desc[i].length = ep->curpacksize;
305 offs += ep->curpacksize;
306 }
307
308 urb->transfer_buffer_length = offs;
309 urb->number_of_packets = urb_ctx->packets;
310 break;
311
312 case SND_USB_ENDPOINT_TYPE_SYNC:
313 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
314 urb->iso_frame_desc[0].offset = 0;
315 break;
316 }
317}
318
319/*
320 * Send output urbs that have been prepared previously. URBs are dequeued
321 * from ep->ready_playback_urbs and in case there there aren't any available
322 * or there are no packets that have been prepared, this function does
323 * nothing.
324 *
325 * The reason why the functionality of sending and preparing URBs is separated
326 * is that host controllers don't guarantee the order in which they return
327 * inbound and outbound packets to their submitters.
328 *
329 * This function is only used for implicit feedback endpoints. For endpoints
330 * driven by dedicated sync endpoints, URBs are immediately re-submitted
331 * from their completion handler.
332 */
333static void queue_pending_output_urbs(struct snd_usb_endpoint *ep)
334{
335 while (test_bit(EP_FLAG_RUNNING, &ep->flags)) {
336
337 unsigned long flags;
338 struct snd_usb_packet_info *packet;
339 struct snd_urb_ctx *ctx = NULL;
340 int err, i;
341
342 spin_lock_irqsave(&ep->lock, flags);
343 if (ep->next_packet_read_pos != ep->next_packet_write_pos) {
344 packet = ep->next_packet + ep->next_packet_read_pos;
345 ep->next_packet_read_pos++;
346 ep->next_packet_read_pos %= MAX_URBS;
347
348 /* take URB out of FIFO */
349 if (!list_empty(&ep->ready_playback_urbs)) {
350 ctx = list_first_entry(&ep->ready_playback_urbs,
351 struct snd_urb_ctx, ready_list);
352 list_del_init(&ctx->ready_list);
353 }
354 }
355 spin_unlock_irqrestore(&ep->lock, flags);
356
357 if (ctx == NULL)
358 return;
359
360 /* copy over the length information */
361 for (i = 0; i < packet->packets; i++)
362 ctx->packet_size[i] = packet->packet_size[i];
363
364 /* call the data handler to fill in playback data */
365 prepare_outbound_urb(ep, ctx);
366
367 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
368 if (err < 0)
369 usb_audio_err(ep->chip,
370 "Unable to submit urb #%d: %d (urb %p)\n",
371 ctx->index, err, ctx->urb);
372 else
373 set_bit(ctx->index, &ep->active_mask);
374 }
375}
376
377/*
378 * complete callback for urbs
379 */
380static void snd_complete_urb(struct urb *urb)
381{
382 struct snd_urb_ctx *ctx = urb->context;
383 struct snd_usb_endpoint *ep = ctx->ep;
384 struct snd_pcm_substream *substream;
385 unsigned long flags;
386 int err;
387
388 if (unlikely(urb->status == -ENOENT || /* unlinked */
389 urb->status == -ENODEV || /* device removed */
390 urb->status == -ECONNRESET || /* unlinked */
391 urb->status == -ESHUTDOWN)) /* device disabled */
392 goto exit_clear;
393 /* device disconnected */
394 if (unlikely(atomic_read(&ep->chip->shutdown)))
395 goto exit_clear;
396
397 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
398 goto exit_clear;
399
400 if (usb_pipeout(ep->pipe)) {
401 retire_outbound_urb(ep, ctx);
402 /* can be stopped during retire callback */
403 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
404 goto exit_clear;
405
406 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
407 spin_lock_irqsave(&ep->lock, flags);
408 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
409 spin_unlock_irqrestore(&ep->lock, flags);
410 queue_pending_output_urbs(ep);
411
412 goto exit_clear;
413 }
414
415 prepare_outbound_urb(ep, ctx);
416 /* can be stopped during prepare callback */
417 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
418 goto exit_clear;
419 } else {
420 retire_inbound_urb(ep, ctx);
421 /* can be stopped during retire callback */
422 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
423 goto exit_clear;
424
425 prepare_inbound_urb(ep, ctx);
426 }
427
428 err = usb_submit_urb(urb, GFP_ATOMIC);
429 if (err == 0)
430 return;
431
432 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
433 if (ep->data_subs && ep->data_subs->pcm_substream) {
434 substream = ep->data_subs->pcm_substream;
435 snd_pcm_stop_xrun(substream);
436 }
437
438exit_clear:
439 clear_bit(ctx->index, &ep->active_mask);
440}
441
442/**
443 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
444 *
445 * @chip: The chip
446 * @alts: The USB host interface
447 * @ep_num: The number of the endpoint to use
448 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
449 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
450 *
451 * If the requested endpoint has not been added to the given chip before,
452 * a new instance is created. Otherwise, a pointer to the previoulsy
453 * created instance is returned. In case of any error, NULL is returned.
454 *
455 * New endpoints will be added to chip->ep_list and must be freed by
456 * calling snd_usb_endpoint_free().
457 *
458 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
459 * bNumEndpoints > 1 beforehand.
460 */
461struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
462 struct usb_host_interface *alts,
463 int ep_num, int direction, int type)
464{
465 struct snd_usb_endpoint *ep;
466 int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK;
467
468 if (WARN_ON(!alts))
469 return NULL;
470
471 mutex_lock(&chip->mutex);
472
473 list_for_each_entry(ep, &chip->ep_list, list) {
474 if (ep->ep_num == ep_num &&
475 ep->iface == alts->desc.bInterfaceNumber &&
476 ep->altsetting == alts->desc.bAlternateSetting) {
477 usb_audio_dbg(ep->chip,
478 "Re-using EP %x in iface %d,%d @%p\n",
479 ep_num, ep->iface, ep->altsetting, ep);
480 goto __exit_unlock;
481 }
482 }
483
484 usb_audio_dbg(chip, "Creating new %s %s endpoint #%x\n",
485 is_playback ? "playback" : "capture",
486 type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync",
487 ep_num);
488
489 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
490 if (!ep)
491 goto __exit_unlock;
492
493 ep->chip = chip;
494 spin_lock_init(&ep->lock);
495 ep->type = type;
496 ep->ep_num = ep_num;
497 ep->iface = alts->desc.bInterfaceNumber;
498 ep->altsetting = alts->desc.bAlternateSetting;
499 INIT_LIST_HEAD(&ep->ready_playback_urbs);
500 ep_num &= USB_ENDPOINT_NUMBER_MASK;
501
502 if (is_playback)
503 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
504 else
505 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
506
507 if (type == SND_USB_ENDPOINT_TYPE_SYNC) {
508 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
509 get_endpoint(alts, 1)->bRefresh >= 1 &&
510 get_endpoint(alts, 1)->bRefresh <= 9)
511 ep->syncinterval = get_endpoint(alts, 1)->bRefresh;
512 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
513 ep->syncinterval = 1;
514 else if (get_endpoint(alts, 1)->bInterval >= 1 &&
515 get_endpoint(alts, 1)->bInterval <= 16)
516 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1;
517 else
518 ep->syncinterval = 3;
519
520 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize);
521 }
522
523 list_add_tail(&ep->list, &chip->ep_list);
524
525 ep->is_implicit_feedback = 0;
526
527__exit_unlock:
528 mutex_unlock(&chip->mutex);
529
530 return ep;
531}
532
533/*
534 * wait until all urbs are processed.
535 */
536static int wait_clear_urbs(struct snd_usb_endpoint *ep)
537{
538 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
539 int alive;
540
541 do {
542 alive = bitmap_weight(&ep->active_mask, ep->nurbs);
543 if (!alive)
544 break;
545
546 schedule_timeout_uninterruptible(1);
547 } while (time_before(jiffies, end_time));
548
549 if (alive)
550 usb_audio_err(ep->chip,
551 "timeout: still %d active urbs on EP #%x\n",
552 alive, ep->ep_num);
553 clear_bit(EP_FLAG_STOPPING, &ep->flags);
554
555 ep->data_subs = NULL;
556 ep->sync_slave = NULL;
557 ep->retire_data_urb = NULL;
558 ep->prepare_data_urb = NULL;
559
560 return 0;
561}
562
563/* sync the pending stop operation;
564 * this function itself doesn't trigger the stop operation
565 */
566void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
567{
568 if (ep && test_bit(EP_FLAG_STOPPING, &ep->flags))
569 wait_clear_urbs(ep);
570}
571
572/*
573 * unlink active urbs.
574 */
575static int deactivate_urbs(struct snd_usb_endpoint *ep, bool force)
576{
577 unsigned int i;
578
579 if (!force && atomic_read(&ep->chip->shutdown)) /* to be sure... */
580 return -EBADFD;
581
582 clear_bit(EP_FLAG_RUNNING, &ep->flags);
583
584 INIT_LIST_HEAD(&ep->ready_playback_urbs);
585 ep->next_packet_read_pos = 0;
586 ep->next_packet_write_pos = 0;
587
588 for (i = 0; i < ep->nurbs; i++) {
589 if (test_bit(i, &ep->active_mask)) {
590 if (!test_and_set_bit(i, &ep->unlink_mask)) {
591 struct urb *u = ep->urb[i].urb;
592 usb_unlink_urb(u);
593 }
594 }
595 }
596
597 return 0;
598}
599
600/*
601 * release an endpoint's urbs
602 */
603static void release_urbs(struct snd_usb_endpoint *ep, int force)
604{
605 int i;
606
607 /* route incoming urbs to nirvana */
608 ep->retire_data_urb = NULL;
609 ep->prepare_data_urb = NULL;
610
611 /* stop urbs */
612 deactivate_urbs(ep, force);
613 wait_clear_urbs(ep);
614
615 for (i = 0; i < ep->nurbs; i++)
616 release_urb_ctx(&ep->urb[i]);
617
618 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
619 ep->syncbuf, ep->sync_dma);
620
621 ep->syncbuf = NULL;
622 ep->nurbs = 0;
623}
624
625/*
626 * Check data endpoint for format differences
627 */
628static bool check_ep_params(struct snd_usb_endpoint *ep,
629 snd_pcm_format_t pcm_format,
630 unsigned int channels,
631 unsigned int period_bytes,
632 unsigned int frames_per_period,
633 unsigned int periods_per_buffer,
634 struct audioformat *fmt,
635 struct snd_usb_endpoint *sync_ep)
636{
637 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
638 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
639 unsigned int max_urbs;
640 int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels;
641 int tx_length_quirk = (ep->chip->tx_length_quirk &&
642 usb_pipeout(ep->pipe));
643 bool ret = 1;
644
645 if (pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
646 /*
647 * When operating in DSD DOP mode, the size of a sample frame
648 * in hardware differs from the actual physical format width
649 * because we need to make room for the DOP markers.
650 */
651 frame_bits += channels << 3;
652 }
653
654 ret = ret && (ep->datainterval == fmt->datainterval);
655 ret = ret && (ep->stride == frame_bits >> 3);
656
657 switch (pcm_format) {
658 case SNDRV_PCM_FORMAT_U8:
659 ret = ret && (ep->silence_value == 0x80);
660 break;
661 case SNDRV_PCM_FORMAT_DSD_U8:
662 case SNDRV_PCM_FORMAT_DSD_U16_LE:
663 case SNDRV_PCM_FORMAT_DSD_U32_LE:
664 case SNDRV_PCM_FORMAT_DSD_U16_BE:
665 case SNDRV_PCM_FORMAT_DSD_U32_BE:
666 ret = ret && (ep->silence_value == 0x69);
667 break;
668 default:
669 ret = ret && (ep->silence_value == 0);
670 }
671
672 /* assume max. frequency is 50% higher than nominal */
673 ret = ret && (ep->freqmax == ep->freqn + (ep->freqn >> 1));
674 /* Round up freqmax to nearest integer in order to calculate maximum
675 * packet size, which must represent a whole number of frames.
676 * This is accomplished by adding 0x0.ffff before converting the
677 * Q16.16 format into integer.
678 * In order to accurately calculate the maximum packet size when
679 * the data interval is more than 1 (i.e. ep->datainterval > 0),
680 * multiply by the data interval prior to rounding. For instance,
681 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
682 * frames with a data interval of 1, but 11 (10.25) frames with a
683 * data interval of 2.
684 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
685 * maximum datainterval value of 3, at USB full speed, higher for
686 * USB high speed, noting that ep->freqmax is in units of
687 * frames per packet in Q16.16 format.)
688 */
689 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
690 (frame_bits >> 3);
691 if (tx_length_quirk)
692 maxsize += sizeof(__le32); /* Space for length descriptor */
693 /* but wMaxPacketSize might reduce this */
694 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
695 /* whatever fits into a max. size packet */
696 unsigned int data_maxsize = maxsize = ep->maxpacksize;
697
698 if (tx_length_quirk)
699 /* Need to remove the length descriptor to calc freq */
700 data_maxsize -= sizeof(__le32);
701 ret = ret && (ep->freqmax == (data_maxsize / (frame_bits >> 3))
702 << (16 - ep->datainterval));
703 }
704
705 if (ep->fill_max)
706 ret = ret && (ep->curpacksize == ep->maxpacksize);
707 else
708 ret = ret && (ep->curpacksize == maxsize);
709
710 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) {
711 packs_per_ms = 8 >> ep->datainterval;
712 max_packs_per_urb = MAX_PACKS_HS;
713 } else {
714 packs_per_ms = 1;
715 max_packs_per_urb = MAX_PACKS;
716 }
717 if (sync_ep && !snd_usb_endpoint_implicit_feedback_sink(ep))
718 max_packs_per_urb = min(max_packs_per_urb,
719 1U << sync_ep->syncinterval);
720 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
721
722 /*
723 * Capture endpoints need to use small URBs because there's no way
724 * to tell in advance where the next period will end, and we don't
725 * want the next URB to complete much after the period ends.
726 *
727 * Playback endpoints with implicit sync much use the same parameters
728 * as their corresponding capture endpoint.
729 */
730 if (usb_pipein(ep->pipe) ||
731 snd_usb_endpoint_implicit_feedback_sink(ep)) {
732
733 urb_packs = packs_per_ms;
734 /*
735 * Wireless devices can poll at a max rate of once per 4ms.
736 * For dataintervals less than 5, increase the packet count to
737 * allow the host controller to use bursting to fill in the
738 * gaps.
739 */
740 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_WIRELESS) {
741 int interval = ep->datainterval;
742
743 while (interval < 5) {
744 urb_packs <<= 1;
745 ++interval;
746 }
747 }
748 /* make capture URBs <= 1 ms and smaller than a period */
749 urb_packs = min(max_packs_per_urb, urb_packs);
750 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
751 urb_packs >>= 1;
752 ret = ret && (ep->nurbs == MAX_URBS);
753
754 /*
755 * Playback endpoints without implicit sync are adjusted so that
756 * a period fits as evenly as possible in the smallest number of
757 * URBs. The total number of URBs is adjusted to the size of the
758 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
759 */
760 } else {
761 /* determine how small a packet can be */
762 minsize = (ep->freqn >> (16 - ep->datainterval)) *
763 (frame_bits >> 3);
764 /* with sync from device, assume it can be 12% lower */
765 if (sync_ep)
766 minsize -= minsize >> 3;
767 minsize = max(minsize, 1u);
768
769 /* how many packets will contain an entire ALSA period? */
770 max_packs_per_period = DIV_ROUND_UP(period_bytes, minsize);
771
772 /* how many URBs will contain a period? */
773 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
774 max_packs_per_urb);
775 /* how many packets are needed in each URB? */
776 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
777
778 /* limit the number of frames in a single URB */
779 ret = ret && (ep->max_urb_frames ==
780 DIV_ROUND_UP(frames_per_period, urbs_per_period));
781
782 /* try to use enough URBs to contain an entire ALSA buffer */
783 max_urbs = min((unsigned) MAX_URBS,
784 MAX_QUEUE * packs_per_ms / urb_packs);
785 ret = ret && (ep->nurbs == min(max_urbs,
786 urbs_per_period * periods_per_buffer));
787 }
788
789 ret = ret && (ep->datainterval == fmt->datainterval);
790 ret = ret && (ep->maxpacksize == fmt->maxpacksize);
791 ret = ret &&
792 (ep->fill_max == !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX));
793
794 return ret;
795}
796
797/*
798 * configure a data endpoint
799 */
800static int data_ep_set_params(struct snd_usb_endpoint *ep,
801 snd_pcm_format_t pcm_format,
802 unsigned int channels,
803 unsigned int period_bytes,
804 unsigned int frames_per_period,
805 unsigned int periods_per_buffer,
806 struct audioformat *fmt,
807 struct snd_usb_endpoint *sync_ep)
808{
809 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
810 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
811 unsigned int max_urbs, i;
812 int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels;
813 int tx_length_quirk = (ep->chip->tx_length_quirk &&
814 usb_pipeout(ep->pipe));
815
816 if (pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
817 /*
818 * When operating in DSD DOP mode, the size of a sample frame
819 * in hardware differs from the actual physical format width
820 * because we need to make room for the DOP markers.
821 */
822 frame_bits += channels << 3;
823 }
824
825 ep->datainterval = fmt->datainterval;
826 ep->stride = frame_bits >> 3;
827
828 switch (pcm_format) {
829 case SNDRV_PCM_FORMAT_U8:
830 ep->silence_value = 0x80;
831 break;
832 case SNDRV_PCM_FORMAT_DSD_U8:
833 case SNDRV_PCM_FORMAT_DSD_U16_LE:
834 case SNDRV_PCM_FORMAT_DSD_U32_LE:
835 case SNDRV_PCM_FORMAT_DSD_U16_BE:
836 case SNDRV_PCM_FORMAT_DSD_U32_BE:
837 ep->silence_value = 0x69;
838 break;
839 default:
840 ep->silence_value = 0;
841 }
842
843 /* assume max. frequency is 50% higher than nominal */
844 ep->freqmax = ep->freqn + (ep->freqn >> 1);
845 /* Round up freqmax to nearest integer in order to calculate maximum
846 * packet size, which must represent a whole number of frames.
847 * This is accomplished by adding 0x0.ffff before converting the
848 * Q16.16 format into integer.
849 * In order to accurately calculate the maximum packet size when
850 * the data interval is more than 1 (i.e. ep->datainterval > 0),
851 * multiply by the data interval prior to rounding. For instance,
852 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
853 * frames with a data interval of 1, but 11 (10.25) frames with a
854 * data interval of 2.
855 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
856 * maximum datainterval value of 3, at USB full speed, higher for
857 * USB high speed, noting that ep->freqmax is in units of
858 * frames per packet in Q16.16 format.)
859 */
860 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
861 (frame_bits >> 3);
862 if (tx_length_quirk)
863 maxsize += sizeof(__le32); /* Space for length descriptor */
864 /* but wMaxPacketSize might reduce this */
865 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
866 /* whatever fits into a max. size packet */
867 unsigned int data_maxsize = maxsize = ep->maxpacksize;
868
869 if (tx_length_quirk)
870 /* Need to remove the length descriptor to calc freq */
871 data_maxsize -= sizeof(__le32);
872 ep->freqmax = (data_maxsize / (frame_bits >> 3))
873 << (16 - ep->datainterval);
874 }
875
876 if (ep->fill_max)
877 ep->curpacksize = ep->maxpacksize;
878 else
879 ep->curpacksize = maxsize;
880
881 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) {
882 packs_per_ms = 8 >> ep->datainterval;
883 max_packs_per_urb = MAX_PACKS_HS;
884 } else {
885 packs_per_ms = 1;
886 max_packs_per_urb = MAX_PACKS;
887 }
888 if (sync_ep && !snd_usb_endpoint_implicit_feedback_sink(ep))
889 max_packs_per_urb = min(max_packs_per_urb,
890 1U << sync_ep->syncinterval);
891 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
892
893 /*
894 * Capture endpoints need to use small URBs because there's no way
895 * to tell in advance where the next period will end, and we don't
896 * want the next URB to complete much after the period ends.
897 *
898 * Playback endpoints with implicit sync much use the same parameters
899 * as their corresponding capture endpoint.
900 */
901 if (usb_pipein(ep->pipe) ||
902 snd_usb_endpoint_implicit_feedback_sink(ep)) {
903
904 urb_packs = packs_per_ms;
905 /*
906 * Wireless devices can poll at a max rate of once per 4ms.
907 * For dataintervals less than 5, increase the packet count to
908 * allow the host controller to use bursting to fill in the
909 * gaps.
910 */
911 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_WIRELESS) {
912 int interval = ep->datainterval;
913 while (interval < 5) {
914 urb_packs <<= 1;
915 ++interval;
916 }
917 }
918 /* make capture URBs <= 1 ms and smaller than a period */
919 urb_packs = min(max_packs_per_urb, urb_packs);
920 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
921 urb_packs >>= 1;
922 ep->nurbs = MAX_URBS;
923
924 /*
925 * Playback endpoints without implicit sync are adjusted so that
926 * a period fits as evenly as possible in the smallest number of
927 * URBs. The total number of URBs is adjusted to the size of the
928 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
929 */
930 } else {
931 /* determine how small a packet can be */
932 minsize = (ep->freqn >> (16 - ep->datainterval)) *
933 (frame_bits >> 3);
934 /* with sync from device, assume it can be 12% lower */
935 if (sync_ep)
936 minsize -= minsize >> 3;
937 minsize = max(minsize, 1u);
938
939 /* how many packets will contain an entire ALSA period? */
940 max_packs_per_period = DIV_ROUND_UP(period_bytes, minsize);
941
942 /* how many URBs will contain a period? */
943 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
944 max_packs_per_urb);
945 /* how many packets are needed in each URB? */
946 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
947
948 /* limit the number of frames in a single URB */
949 ep->max_urb_frames = DIV_ROUND_UP(frames_per_period,
950 urbs_per_period);
951
952 /* try to use enough URBs to contain an entire ALSA buffer */
953 max_urbs = min((unsigned) MAX_URBS,
954 MAX_QUEUE * packs_per_ms / urb_packs);
955 ep->nurbs = min(max_urbs, urbs_per_period * periods_per_buffer);
956 }
957
958 /* allocate and initialize data urbs */
959 for (i = 0; i < ep->nurbs; i++) {
960 struct snd_urb_ctx *u = &ep->urb[i];
961 u->index = i;
962 u->ep = ep;
963 u->packets = urb_packs;
964 u->buffer_size = maxsize * u->packets;
965
966 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
967 u->packets++; /* for transfer delimiter */
968 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
969 if (!u->urb)
970 goto out_of_memory;
971
972 u->urb->transfer_buffer =
973 usb_alloc_coherent(ep->chip->dev, u->buffer_size,
974 GFP_KERNEL, &u->urb->transfer_dma);
975 if (!u->urb->transfer_buffer)
976 goto out_of_memory;
977 u->urb->pipe = ep->pipe;
978 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
979 u->urb->interval = 1 << ep->datainterval;
980 u->urb->context = u;
981 u->urb->complete = snd_complete_urb;
982 INIT_LIST_HEAD(&u->ready_list);
983 }
984
985 return 0;
986
987out_of_memory:
988 release_urbs(ep, 0);
989 return -ENOMEM;
990}
991
992/*
993 * configure a sync endpoint
994 */
995static int sync_ep_set_params(struct snd_usb_endpoint *ep)
996{
997 int i;
998
999 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4,
1000 GFP_KERNEL, &ep->sync_dma);
1001 if (!ep->syncbuf)
1002 return -ENOMEM;
1003
1004 for (i = 0; i < SYNC_URBS; i++) {
1005 struct snd_urb_ctx *u = &ep->urb[i];
1006 u->index = i;
1007 u->ep = ep;
1008 u->packets = 1;
1009 u->urb = usb_alloc_urb(1, GFP_KERNEL);
1010 if (!u->urb)
1011 goto out_of_memory;
1012 u->urb->transfer_buffer = ep->syncbuf + i * 4;
1013 u->urb->transfer_dma = ep->sync_dma + i * 4;
1014 u->urb->transfer_buffer_length = 4;
1015 u->urb->pipe = ep->pipe;
1016 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1017 u->urb->number_of_packets = 1;
1018 u->urb->interval = 1 << ep->syncinterval;
1019 u->urb->context = u;
1020 u->urb->complete = snd_complete_urb;
1021 }
1022
1023 ep->nurbs = SYNC_URBS;
1024
1025 return 0;
1026
1027out_of_memory:
1028 release_urbs(ep, 0);
1029 return -ENOMEM;
1030}
1031
1032/**
1033 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
1034 *
1035 * @ep: the snd_usb_endpoint to configure
1036 * @pcm_format: the audio fomat.
1037 * @channels: the number of audio channels.
1038 * @period_bytes: the number of bytes in one alsa period.
1039 * @period_frames: the number of frames in one alsa period.
1040 * @buffer_periods: the number of periods in one alsa buffer.
1041 * @rate: the frame rate.
1042 * @fmt: the USB audio format information
1043 * @sync_ep: the sync endpoint to use, if any
1044 *
1045 * Determine the number of URBs to be used on this endpoint.
1046 * An endpoint must be configured before it can be started.
1047 * An endpoint that is already running can not be reconfigured.
1048 */
1049int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
1050 snd_pcm_format_t pcm_format,
1051 unsigned int channels,
1052 unsigned int period_bytes,
1053 unsigned int period_frames,
1054 unsigned int buffer_periods,
1055 unsigned int rate,
1056 struct audioformat *fmt,
1057 struct snd_usb_endpoint *sync_ep)
1058{
1059 int err;
1060
1061 if (ep->use_count != 0) {
1062 bool check = ep->is_implicit_feedback &&
1063 check_ep_params(ep, pcm_format,
1064 channels, period_bytes,
1065 period_frames, buffer_periods,
1066 fmt, sync_ep);
1067
1068 if (!check) {
1069 usb_audio_warn(ep->chip,
1070 "Unable to change format on ep #%x: already in use\n",
1071 ep->ep_num);
1072 return -EBUSY;
1073 }
1074
1075 usb_audio_dbg(ep->chip,
1076 "Ep #%x already in use as implicit feedback but format not changed\n",
1077 ep->ep_num);
1078 return 0;
1079 }
1080
1081 /* release old buffers, if any */
1082 release_urbs(ep, 0);
1083
1084 ep->datainterval = fmt->datainterval;
1085 ep->maxpacksize = fmt->maxpacksize;
1086 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
1087
1088 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL) {
1089 ep->freqn = get_usb_full_speed_rate(rate);
1090 ep->pps = 1000 >> ep->datainterval;
1091 } else {
1092 ep->freqn = get_usb_high_speed_rate(rate);
1093 ep->pps = 8000 >> ep->datainterval;
1094 }
1095
1096 ep->sample_rem = rate % ep->pps;
1097 ep->packsize[0] = rate / ep->pps;
1098 ep->packsize[1] = (rate + (ep->pps - 1)) / ep->pps;
1099
1100 /* calculate the frequency in 16.16 format */
1101 ep->freqm = ep->freqn;
1102 ep->freqshift = INT_MIN;
1103
1104 ep->phase = 0;
1105
1106 switch (ep->type) {
1107 case SND_USB_ENDPOINT_TYPE_DATA:
1108 err = data_ep_set_params(ep, pcm_format, channels,
1109 period_bytes, period_frames,
1110 buffer_periods, fmt, sync_ep);
1111 break;
1112 case SND_USB_ENDPOINT_TYPE_SYNC:
1113 err = sync_ep_set_params(ep);
1114 break;
1115 default:
1116 err = -EINVAL;
1117 }
1118
1119 usb_audio_dbg(ep->chip,
1120 "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
1121 ep->ep_num, ep->type, ep->nurbs, err);
1122
1123 return err;
1124}
1125
1126/**
1127 * snd_usb_endpoint_start: start an snd_usb_endpoint
1128 *
1129 * @ep: the endpoint to start
1130 *
1131 * A call to this function will increment the use count of the endpoint.
1132 * In case it is not already running, the URBs for this endpoint will be
1133 * submitted. Otherwise, this function does nothing.
1134 *
1135 * Must be balanced to calls of snd_usb_endpoint_stop().
1136 *
1137 * Returns an error if the URB submission failed, 0 in all other cases.
1138 */
1139int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
1140{
1141 int err;
1142 unsigned int i;
1143
1144 if (atomic_read(&ep->chip->shutdown))
1145 return -EBADFD;
1146
1147 /* already running? */
1148 if (++ep->use_count != 1)
1149 return 0;
1150
1151 /* just to be sure */
1152 deactivate_urbs(ep, false);
1153
1154 ep->active_mask = 0;
1155 ep->unlink_mask = 0;
1156 ep->phase = 0;
1157 ep->sample_accum = 0;
1158
1159 snd_usb_endpoint_start_quirk(ep);
1160
1161 /*
1162 * If this endpoint has a data endpoint as implicit feedback source,
1163 * don't start the urbs here. Instead, mark them all as available,
1164 * wait for the record urbs to return and queue the playback urbs
1165 * from that context.
1166 */
1167
1168 set_bit(EP_FLAG_RUNNING, &ep->flags);
1169
1170 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
1171 for (i = 0; i < ep->nurbs; i++) {
1172 struct snd_urb_ctx *ctx = ep->urb + i;
1173 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
1174 }
1175
1176 return 0;
1177 }
1178
1179 for (i = 0; i < ep->nurbs; i++) {
1180 struct urb *urb = ep->urb[i].urb;
1181
1182 if (snd_BUG_ON(!urb))
1183 goto __error;
1184
1185 if (usb_pipeout(ep->pipe)) {
1186 prepare_outbound_urb(ep, urb->context);
1187 } else {
1188 prepare_inbound_urb(ep, urb->context);
1189 }
1190
1191 err = usb_submit_urb(urb, GFP_ATOMIC);
1192 if (err < 0) {
1193 usb_audio_err(ep->chip,
1194 "cannot submit urb %d, error %d: %s\n",
1195 i, err, usb_error_string(err));
1196 goto __error;
1197 }
1198 set_bit(i, &ep->active_mask);
1199 }
1200
1201 return 0;
1202
1203__error:
1204 clear_bit(EP_FLAG_RUNNING, &ep->flags);
1205 ep->use_count--;
1206 deactivate_urbs(ep, false);
1207 return -EPIPE;
1208}
1209
1210/**
1211 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
1212 *
1213 * @ep: the endpoint to stop (may be NULL)
1214 *
1215 * A call to this function will decrement the use count of the endpoint.
1216 * In case the last user has requested the endpoint stop, the URBs will
1217 * actually be deactivated.
1218 *
1219 * Must be balanced to calls of snd_usb_endpoint_start().
1220 *
1221 * The caller needs to synchronize the pending stop operation via
1222 * snd_usb_endpoint_sync_pending_stop().
1223 */
1224void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep)
1225{
1226 if (!ep)
1227 return;
1228
1229 if (snd_BUG_ON(ep->use_count == 0))
1230 return;
1231
1232 if (--ep->use_count == 0) {
1233 deactivate_urbs(ep, false);
1234 set_bit(EP_FLAG_STOPPING, &ep->flags);
1235 }
1236}
1237
1238/**
1239 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
1240 *
1241 * @ep: the endpoint to deactivate
1242 *
1243 * If the endpoint is not currently in use, this functions will
1244 * deactivate its associated URBs.
1245 *
1246 * In case of any active users, this functions does nothing.
1247 */
1248void snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep)
1249{
1250 if (!ep)
1251 return;
1252
1253 if (ep->use_count != 0)
1254 return;
1255
1256 deactivate_urbs(ep, true);
1257 wait_clear_urbs(ep);
1258}
1259
1260/**
1261 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1262 *
1263 * @ep: the endpoint to release
1264 *
1265 * This function does not care for the endpoint's use count but will tear
1266 * down all the streaming URBs immediately.
1267 */
1268void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1269{
1270 release_urbs(ep, 1);
1271}
1272
1273/**
1274 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
1275 *
1276 * @ep: the endpoint to free
1277 *
1278 * This free all resources of the given ep.
1279 */
1280void snd_usb_endpoint_free(struct snd_usb_endpoint *ep)
1281{
1282 kfree(ep);
1283}
1284
1285/**
1286 * snd_usb_handle_sync_urb: parse an USB sync packet
1287 *
1288 * @ep: the endpoint to handle the packet
1289 * @sender: the sending endpoint
1290 * @urb: the received packet
1291 *
1292 * This function is called from the context of an endpoint that received
1293 * the packet and is used to let another endpoint object handle the payload.
1294 */
1295void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1296 struct snd_usb_endpoint *sender,
1297 const struct urb *urb)
1298{
1299 int shift;
1300 unsigned int f;
1301 unsigned long flags;
1302
1303 snd_BUG_ON(ep == sender);
1304
1305 /*
1306 * In case the endpoint is operating in implicit feedback mode, prepare
1307 * a new outbound URB that has the same layout as the received packet
1308 * and add it to the list of pending urbs. queue_pending_output_urbs()
1309 * will take care of them later.
1310 */
1311 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1312 ep->use_count != 0) {
1313
1314 /* implicit feedback case */
1315 int i, bytes = 0;
1316 struct snd_urb_ctx *in_ctx;
1317 struct snd_usb_packet_info *out_packet;
1318
1319 in_ctx = urb->context;
1320
1321 /* Count overall packet size */
1322 for (i = 0; i < in_ctx->packets; i++)
1323 if (urb->iso_frame_desc[i].status == 0)
1324 bytes += urb->iso_frame_desc[i].actual_length;
1325
1326 /*
1327 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1328 * streaming once it received a 0-byte OUT URB
1329 */
1330 if (bytes == 0)
1331 return;
1332
1333 spin_lock_irqsave(&ep->lock, flags);
1334 out_packet = ep->next_packet + ep->next_packet_write_pos;
1335
1336 /*
1337 * Iterate through the inbound packet and prepare the lengths
1338 * for the output packet. The OUT packet we are about to send
1339 * will have the same amount of payload bytes per stride as the
1340 * IN packet we just received. Since the actual size is scaled
1341 * by the stride, use the sender stride to calculate the length
1342 * in case the number of channels differ between the implicitly
1343 * fed-back endpoint and the synchronizing endpoint.
1344 */
1345
1346 out_packet->packets = in_ctx->packets;
1347 for (i = 0; i < in_ctx->packets; i++) {
1348 if (urb->iso_frame_desc[i].status == 0)
1349 out_packet->packet_size[i] =
1350 urb->iso_frame_desc[i].actual_length / sender->stride;
1351 else
1352 out_packet->packet_size[i] = 0;
1353 }
1354
1355 ep->next_packet_write_pos++;
1356 ep->next_packet_write_pos %= MAX_URBS;
1357 spin_unlock_irqrestore(&ep->lock, flags);
1358 queue_pending_output_urbs(ep);
1359
1360 return;
1361 }
1362
1363 /*
1364 * process after playback sync complete
1365 *
1366 * Full speed devices report feedback values in 10.14 format as samples
1367 * per frame, high speed devices in 16.16 format as samples per
1368 * microframe.
1369 *
1370 * Because the Audio Class 1 spec was written before USB 2.0, many high
1371 * speed devices use a wrong interpretation, some others use an
1372 * entirely different format.
1373 *
1374 * Therefore, we cannot predict what format any particular device uses
1375 * and must detect it automatically.
1376 */
1377
1378 if (urb->iso_frame_desc[0].status != 0 ||
1379 urb->iso_frame_desc[0].actual_length < 3)
1380 return;
1381
1382 f = le32_to_cpup(urb->transfer_buffer);
1383 if (urb->iso_frame_desc[0].actual_length == 3)
1384 f &= 0x00ffffff;
1385 else
1386 f &= 0x0fffffff;
1387
1388 if (f == 0)
1389 return;
1390
1391 if (unlikely(sender->tenor_fb_quirk)) {
1392 /*
1393 * Devices based on Tenor 8802 chipsets (TEAC UD-H01
1394 * and others) sometimes change the feedback value
1395 * by +/- 0x1.0000.
1396 */
1397 if (f < ep->freqn - 0x8000)
1398 f += 0xf000;
1399 else if (f > ep->freqn + 0x8000)
1400 f -= 0xf000;
1401 } else if (unlikely(ep->freqshift == INT_MIN)) {
1402 /*
1403 * The first time we see a feedback value, determine its format
1404 * by shifting it left or right until it matches the nominal
1405 * frequency value. This assumes that the feedback does not
1406 * differ from the nominal value more than +50% or -25%.
1407 */
1408 shift = 0;
1409 while (f < ep->freqn - ep->freqn / 4) {
1410 f <<= 1;
1411 shift++;
1412 }
1413 while (f > ep->freqn + ep->freqn / 2) {
1414 f >>= 1;
1415 shift--;
1416 }
1417 ep->freqshift = shift;
1418 } else if (ep->freqshift >= 0)
1419 f <<= ep->freqshift;
1420 else
1421 f >>= -ep->freqshift;
1422
1423 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1424 /*
1425 * If the frequency looks valid, set it.
1426 * This value is referred to in prepare_playback_urb().
1427 */
1428 spin_lock_irqsave(&ep->lock, flags);
1429 ep->freqm = f;
1430 spin_unlock_irqrestore(&ep->lock, flags);
1431 } else {
1432 /*
1433 * Out of range; maybe the shift value is wrong.
1434 * Reset it so that we autodetect again the next time.
1435 */
1436 ep->freqshift = INT_MIN;
1437 }
1438}
1439
1/*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
6 *
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
15 *
16 */
17
18#include <linux/gfp.h>
19#include <linux/init.h>
20#include <linux/ratelimit.h>
21#include <linux/usb.h>
22#include <linux/usb/audio.h>
23#include <linux/slab.h>
24
25#include <sound/core.h>
26#include <sound/pcm.h>
27#include <sound/pcm_params.h>
28
29#include "usbaudio.h"
30#include "helper.h"
31#include "card.h"
32#include "endpoint.h"
33#include "pcm.h"
34
35#define EP_FLAG_ACTIVATED 0
36#define EP_FLAG_RUNNING 1
37
38/*
39 * snd_usb_endpoint is a model that abstracts everything related to an
40 * USB endpoint and its streaming.
41 *
42 * There are functions to activate and deactivate the streaming URBs and
43 * optional callbacks to let the pcm logic handle the actual content of the
44 * packets for playback and record. Thus, the bus streaming and the audio
45 * handlers are fully decoupled.
46 *
47 * There are two different types of endpoints in audio applications.
48 *
49 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
50 * inbound and outbound traffic.
51 *
52 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
53 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
54 * (3 or 4 bytes).
55 *
56 * Each endpoint has to be configured prior to being used by calling
57 * snd_usb_endpoint_set_params().
58 *
59 * The model incorporates a reference counting, so that multiple users
60 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
61 * only the first user will effectively start the URBs, and only the last
62 * one to stop it will tear the URBs down again.
63 */
64
65/*
66 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
67 * this will overflow at approx 524 kHz
68 */
69static inline unsigned get_usb_full_speed_rate(unsigned int rate)
70{
71 return ((rate << 13) + 62) / 125;
72}
73
74/*
75 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
76 * this will overflow at approx 4 MHz
77 */
78static inline unsigned get_usb_high_speed_rate(unsigned int rate)
79{
80 return ((rate << 10) + 62) / 125;
81}
82
83/*
84 * release a urb data
85 */
86static void release_urb_ctx(struct snd_urb_ctx *u)
87{
88 if (u->buffer_size)
89 usb_free_coherent(u->ep->chip->dev, u->buffer_size,
90 u->urb->transfer_buffer,
91 u->urb->transfer_dma);
92 usb_free_urb(u->urb);
93 u->urb = NULL;
94}
95
96static const char *usb_error_string(int err)
97{
98 switch (err) {
99 case -ENODEV:
100 return "no device";
101 case -ENOENT:
102 return "endpoint not enabled";
103 case -EPIPE:
104 return "endpoint stalled";
105 case -ENOSPC:
106 return "not enough bandwidth";
107 case -ESHUTDOWN:
108 return "device disabled";
109 case -EHOSTUNREACH:
110 return "device suspended";
111 case -EINVAL:
112 case -EAGAIN:
113 case -EFBIG:
114 case -EMSGSIZE:
115 return "internal error";
116 default:
117 return "unknown error";
118 }
119}
120
121/**
122 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
123 *
124 * @ep: The snd_usb_endpoint
125 *
126 * Determine whether an endpoint is driven by an implicit feedback
127 * data endpoint source.
128 */
129int snd_usb_endpoint_implict_feedback_sink(struct snd_usb_endpoint *ep)
130{
131 return ep->sync_master &&
132 ep->sync_master->type == SND_USB_ENDPOINT_TYPE_DATA &&
133 ep->type == SND_USB_ENDPOINT_TYPE_DATA &&
134 usb_pipeout(ep->pipe);
135}
136
137/*
138 * For streaming based on information derived from sync endpoints,
139 * prepare_outbound_urb_sizes() will call next_packet_size() to
140 * determine the number of samples to be sent in the next packet.
141 *
142 * For implicit feedback, next_packet_size() is unused.
143 */
144int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep)
145{
146 unsigned long flags;
147 int ret;
148
149 if (ep->fill_max)
150 return ep->maxframesize;
151
152 spin_lock_irqsave(&ep->lock, flags);
153 ep->phase = (ep->phase & 0xffff)
154 + (ep->freqm << ep->datainterval);
155 ret = min(ep->phase >> 16, ep->maxframesize);
156 spin_unlock_irqrestore(&ep->lock, flags);
157
158 return ret;
159}
160
161static void retire_outbound_urb(struct snd_usb_endpoint *ep,
162 struct snd_urb_ctx *urb_ctx)
163{
164 if (ep->retire_data_urb)
165 ep->retire_data_urb(ep->data_subs, urb_ctx->urb);
166}
167
168static void retire_inbound_urb(struct snd_usb_endpoint *ep,
169 struct snd_urb_ctx *urb_ctx)
170{
171 struct urb *urb = urb_ctx->urb;
172
173 if (ep->sync_slave)
174 snd_usb_handle_sync_urb(ep->sync_slave, ep, urb);
175
176 if (ep->retire_data_urb)
177 ep->retire_data_urb(ep->data_subs, urb);
178}
179
180/*
181 * Prepare a PLAYBACK urb for submission to the bus.
182 */
183static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
184 struct snd_urb_ctx *ctx)
185{
186 int i;
187 struct urb *urb = ctx->urb;
188 unsigned char *cp = urb->transfer_buffer;
189
190 urb->dev = ep->chip->dev; /* we need to set this at each time */
191
192 switch (ep->type) {
193 case SND_USB_ENDPOINT_TYPE_DATA:
194 if (ep->prepare_data_urb) {
195 ep->prepare_data_urb(ep->data_subs, urb);
196 } else {
197 /* no data provider, so send silence */
198 unsigned int offs = 0;
199 for (i = 0; i < ctx->packets; ++i) {
200 int counts;
201
202 if (ctx->packet_size[i])
203 counts = ctx->packet_size[i];
204 else
205 counts = snd_usb_endpoint_next_packet_size(ep);
206
207 urb->iso_frame_desc[i].offset = offs * ep->stride;
208 urb->iso_frame_desc[i].length = counts * ep->stride;
209 offs += counts;
210 }
211
212 urb->number_of_packets = ctx->packets;
213 urb->transfer_buffer_length = offs * ep->stride;
214 memset(urb->transfer_buffer, ep->silence_value,
215 offs * ep->stride);
216 }
217 break;
218
219 case SND_USB_ENDPOINT_TYPE_SYNC:
220 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
221 /*
222 * fill the length and offset of each urb descriptor.
223 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
224 */
225 urb->iso_frame_desc[0].length = 4;
226 urb->iso_frame_desc[0].offset = 0;
227 cp[0] = ep->freqn;
228 cp[1] = ep->freqn >> 8;
229 cp[2] = ep->freqn >> 16;
230 cp[3] = ep->freqn >> 24;
231 } else {
232 /*
233 * fill the length and offset of each urb descriptor.
234 * the fixed 10.14 frequency is passed through the pipe.
235 */
236 urb->iso_frame_desc[0].length = 3;
237 urb->iso_frame_desc[0].offset = 0;
238 cp[0] = ep->freqn >> 2;
239 cp[1] = ep->freqn >> 10;
240 cp[2] = ep->freqn >> 18;
241 }
242
243 break;
244 }
245}
246
247/*
248 * Prepare a CAPTURE or SYNC urb for submission to the bus.
249 */
250static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep,
251 struct snd_urb_ctx *urb_ctx)
252{
253 int i, offs;
254 struct urb *urb = urb_ctx->urb;
255
256 urb->dev = ep->chip->dev; /* we need to set this at each time */
257
258 switch (ep->type) {
259 case SND_USB_ENDPOINT_TYPE_DATA:
260 offs = 0;
261 for (i = 0; i < urb_ctx->packets; i++) {
262 urb->iso_frame_desc[i].offset = offs;
263 urb->iso_frame_desc[i].length = ep->curpacksize;
264 offs += ep->curpacksize;
265 }
266
267 urb->transfer_buffer_length = offs;
268 urb->number_of_packets = urb_ctx->packets;
269 break;
270
271 case SND_USB_ENDPOINT_TYPE_SYNC:
272 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
273 urb->iso_frame_desc[0].offset = 0;
274 break;
275 }
276}
277
278/*
279 * Send output urbs that have been prepared previously. URBs are dequeued
280 * from ep->ready_playback_urbs and in case there there aren't any available
281 * or there are no packets that have been prepared, this function does
282 * nothing.
283 *
284 * The reason why the functionality of sending and preparing URBs is separated
285 * is that host controllers don't guarantee the order in which they return
286 * inbound and outbound packets to their submitters.
287 *
288 * This function is only used for implicit feedback endpoints. For endpoints
289 * driven by dedicated sync endpoints, URBs are immediately re-submitted
290 * from their completion handler.
291 */
292static void queue_pending_output_urbs(struct snd_usb_endpoint *ep)
293{
294 while (test_bit(EP_FLAG_RUNNING, &ep->flags)) {
295
296 unsigned long flags;
297 struct snd_usb_packet_info *uninitialized_var(packet);
298 struct snd_urb_ctx *ctx = NULL;
299 struct urb *urb;
300 int err, i;
301
302 spin_lock_irqsave(&ep->lock, flags);
303 if (ep->next_packet_read_pos != ep->next_packet_write_pos) {
304 packet = ep->next_packet + ep->next_packet_read_pos;
305 ep->next_packet_read_pos++;
306 ep->next_packet_read_pos %= MAX_URBS;
307
308 /* take URB out of FIFO */
309 if (!list_empty(&ep->ready_playback_urbs))
310 ctx = list_first_entry(&ep->ready_playback_urbs,
311 struct snd_urb_ctx, ready_list);
312 }
313 spin_unlock_irqrestore(&ep->lock, flags);
314
315 if (ctx == NULL)
316 return;
317
318 list_del_init(&ctx->ready_list);
319 urb = ctx->urb;
320
321 /* copy over the length information */
322 for (i = 0; i < packet->packets; i++)
323 ctx->packet_size[i] = packet->packet_size[i];
324
325 /* call the data handler to fill in playback data */
326 prepare_outbound_urb(ep, ctx);
327
328 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
329 if (err < 0)
330 snd_printk(KERN_ERR "Unable to submit urb #%d: %d (urb %p)\n",
331 ctx->index, err, ctx->urb);
332 else
333 set_bit(ctx->index, &ep->active_mask);
334 }
335}
336
337/*
338 * complete callback for urbs
339 */
340static void snd_complete_urb(struct urb *urb)
341{
342 struct snd_urb_ctx *ctx = urb->context;
343 struct snd_usb_endpoint *ep = ctx->ep;
344 int err;
345
346 if (unlikely(urb->status == -ENOENT || /* unlinked */
347 urb->status == -ENODEV || /* device removed */
348 urb->status == -ECONNRESET || /* unlinked */
349 urb->status == -ESHUTDOWN || /* device disabled */
350 ep->chip->shutdown)) /* device disconnected */
351 goto exit_clear;
352
353 if (usb_pipeout(ep->pipe)) {
354 retire_outbound_urb(ep, ctx);
355 /* can be stopped during retire callback */
356 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
357 goto exit_clear;
358
359 if (snd_usb_endpoint_implict_feedback_sink(ep)) {
360 unsigned long flags;
361
362 spin_lock_irqsave(&ep->lock, flags);
363 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
364 spin_unlock_irqrestore(&ep->lock, flags);
365 queue_pending_output_urbs(ep);
366
367 goto exit_clear;
368 }
369
370 prepare_outbound_urb(ep, ctx);
371 } else {
372 retire_inbound_urb(ep, ctx);
373 /* can be stopped during retire callback */
374 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
375 goto exit_clear;
376
377 prepare_inbound_urb(ep, ctx);
378 }
379
380 err = usb_submit_urb(urb, GFP_ATOMIC);
381 if (err == 0)
382 return;
383
384 snd_printk(KERN_ERR "cannot submit urb (err = %d)\n", err);
385 //snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
386
387exit_clear:
388 clear_bit(ctx->index, &ep->active_mask);
389}
390
391/**
392 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
393 *
394 * @chip: The chip
395 * @alts: The USB host interface
396 * @ep_num: The number of the endpoint to use
397 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
398 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
399 *
400 * If the requested endpoint has not been added to the given chip before,
401 * a new instance is created. Otherwise, a pointer to the previoulsy
402 * created instance is returned. In case of any error, NULL is returned.
403 *
404 * New endpoints will be added to chip->ep_list and must be freed by
405 * calling snd_usb_endpoint_free().
406 */
407struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
408 struct usb_host_interface *alts,
409 int ep_num, int direction, int type)
410{
411 struct list_head *p;
412 struct snd_usb_endpoint *ep;
413 int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK;
414
415 mutex_lock(&chip->mutex);
416
417 list_for_each(p, &chip->ep_list) {
418 ep = list_entry(p, struct snd_usb_endpoint, list);
419 if (ep->ep_num == ep_num &&
420 ep->iface == alts->desc.bInterfaceNumber &&
421 ep->alt_idx == alts->desc.bAlternateSetting) {
422 snd_printdd(KERN_DEBUG "Re-using EP %x in iface %d,%d @%p\n",
423 ep_num, ep->iface, ep->alt_idx, ep);
424 goto __exit_unlock;
425 }
426 }
427
428 snd_printdd(KERN_DEBUG "Creating new %s %s endpoint #%x\n",
429 is_playback ? "playback" : "capture",
430 type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync",
431 ep_num);
432
433 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
434 if (!ep)
435 goto __exit_unlock;
436
437 ep->chip = chip;
438 spin_lock_init(&ep->lock);
439 ep->type = type;
440 ep->ep_num = ep_num;
441 ep->iface = alts->desc.bInterfaceNumber;
442 ep->alt_idx = alts->desc.bAlternateSetting;
443 INIT_LIST_HEAD(&ep->ready_playback_urbs);
444 ep_num &= USB_ENDPOINT_NUMBER_MASK;
445
446 if (is_playback)
447 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
448 else
449 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
450
451 if (type == SND_USB_ENDPOINT_TYPE_SYNC) {
452 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
453 get_endpoint(alts, 1)->bRefresh >= 1 &&
454 get_endpoint(alts, 1)->bRefresh <= 9)
455 ep->syncinterval = get_endpoint(alts, 1)->bRefresh;
456 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
457 ep->syncinterval = 1;
458 else if (get_endpoint(alts, 1)->bInterval >= 1 &&
459 get_endpoint(alts, 1)->bInterval <= 16)
460 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1;
461 else
462 ep->syncinterval = 3;
463
464 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize);
465 }
466
467 list_add_tail(&ep->list, &chip->ep_list);
468
469__exit_unlock:
470 mutex_unlock(&chip->mutex);
471
472 return ep;
473}
474
475/*
476 * wait until all urbs are processed.
477 */
478static int wait_clear_urbs(struct snd_usb_endpoint *ep)
479{
480 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
481 unsigned int i;
482 int alive;
483
484 do {
485 alive = 0;
486 for (i = 0; i < ep->nurbs; i++)
487 if (test_bit(i, &ep->active_mask))
488 alive++;
489
490 if (!alive)
491 break;
492
493 schedule_timeout_uninterruptible(1);
494 } while (time_before(jiffies, end_time));
495
496 if (alive)
497 snd_printk(KERN_ERR "timeout: still %d active urbs on EP #%x\n",
498 alive, ep->ep_num);
499
500 return 0;
501}
502
503/*
504 * unlink active urbs.
505 */
506static int deactivate_urbs(struct snd_usb_endpoint *ep, int force, int can_sleep)
507{
508 unsigned int i;
509 int async;
510
511 if (!force && ep->chip->shutdown) /* to be sure... */
512 return -EBADFD;
513
514 async = !can_sleep && ep->chip->async_unlink;
515
516 clear_bit(EP_FLAG_RUNNING, &ep->flags);
517
518 INIT_LIST_HEAD(&ep->ready_playback_urbs);
519 ep->next_packet_read_pos = 0;
520 ep->next_packet_write_pos = 0;
521
522 if (!async && in_interrupt())
523 return 0;
524
525 for (i = 0; i < ep->nurbs; i++) {
526 if (test_bit(i, &ep->active_mask)) {
527 if (!test_and_set_bit(i, &ep->unlink_mask)) {
528 struct urb *u = ep->urb[i].urb;
529 if (async)
530 usb_unlink_urb(u);
531 else
532 usb_kill_urb(u);
533 }
534 }
535 }
536
537 return 0;
538}
539
540/*
541 * release an endpoint's urbs
542 */
543static void release_urbs(struct snd_usb_endpoint *ep, int force)
544{
545 int i;
546
547 /* route incoming urbs to nirvana */
548 ep->retire_data_urb = NULL;
549 ep->prepare_data_urb = NULL;
550
551 /* stop urbs */
552 deactivate_urbs(ep, force, 1);
553 wait_clear_urbs(ep);
554
555 for (i = 0; i < ep->nurbs; i++)
556 release_urb_ctx(&ep->urb[i]);
557
558 if (ep->syncbuf)
559 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
560 ep->syncbuf, ep->sync_dma);
561
562 ep->syncbuf = NULL;
563 ep->nurbs = 0;
564}
565
566/*
567 * configure a data endpoint
568 */
569static int data_ep_set_params(struct snd_usb_endpoint *ep,
570 struct snd_pcm_hw_params *hw_params,
571 struct audioformat *fmt,
572 struct snd_usb_endpoint *sync_ep)
573{
574 unsigned int maxsize, i, urb_packs, total_packs, packs_per_ms;
575 int period_bytes = params_period_bytes(hw_params);
576 int format = params_format(hw_params);
577 int is_playback = usb_pipeout(ep->pipe);
578 int frame_bits = snd_pcm_format_physical_width(params_format(hw_params)) *
579 params_channels(hw_params);
580
581 ep->datainterval = fmt->datainterval;
582 ep->stride = frame_bits >> 3;
583 ep->silence_value = format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0;
584
585 /* calculate max. frequency */
586 if (ep->maxpacksize) {
587 /* whatever fits into a max. size packet */
588 maxsize = ep->maxpacksize;
589 ep->freqmax = (maxsize / (frame_bits >> 3))
590 << (16 - ep->datainterval);
591 } else {
592 /* no max. packet size: just take 25% higher than nominal */
593 ep->freqmax = ep->freqn + (ep->freqn >> 2);
594 maxsize = ((ep->freqmax + 0xffff) * (frame_bits >> 3))
595 >> (16 - ep->datainterval);
596 }
597
598 if (ep->fill_max)
599 ep->curpacksize = ep->maxpacksize;
600 else
601 ep->curpacksize = maxsize;
602
603 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL)
604 packs_per_ms = 8 >> ep->datainterval;
605 else
606 packs_per_ms = 1;
607
608 if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) {
609 urb_packs = max(ep->chip->nrpacks, 1);
610 urb_packs = min(urb_packs, (unsigned int) MAX_PACKS);
611 } else {
612 urb_packs = 1;
613 }
614
615 urb_packs *= packs_per_ms;
616
617 if (sync_ep && !snd_usb_endpoint_implict_feedback_sink(ep))
618 urb_packs = min(urb_packs, 1U << sync_ep->syncinterval);
619
620 /* decide how many packets to be used */
621 if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) {
622 unsigned int minsize, maxpacks;
623 /* determine how small a packet can be */
624 minsize = (ep->freqn >> (16 - ep->datainterval))
625 * (frame_bits >> 3);
626 /* with sync from device, assume it can be 12% lower */
627 if (sync_ep)
628 minsize -= minsize >> 3;
629 minsize = max(minsize, 1u);
630 total_packs = (period_bytes + minsize - 1) / minsize;
631 /* we need at least two URBs for queueing */
632 if (total_packs < 2) {
633 total_packs = 2;
634 } else {
635 /* and we don't want too long a queue either */
636 maxpacks = max(MAX_QUEUE * packs_per_ms, urb_packs * 2);
637 total_packs = min(total_packs, maxpacks);
638 }
639 } else {
640 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
641 urb_packs >>= 1;
642 total_packs = MAX_URBS * urb_packs;
643 }
644
645 ep->nurbs = (total_packs + urb_packs - 1) / urb_packs;
646 if (ep->nurbs > MAX_URBS) {
647 /* too much... */
648 ep->nurbs = MAX_URBS;
649 total_packs = MAX_URBS * urb_packs;
650 } else if (ep->nurbs < 2) {
651 /* too little - we need at least two packets
652 * to ensure contiguous playback/capture
653 */
654 ep->nurbs = 2;
655 }
656
657 /* allocate and initialize data urbs */
658 for (i = 0; i < ep->nurbs; i++) {
659 struct snd_urb_ctx *u = &ep->urb[i];
660 u->index = i;
661 u->ep = ep;
662 u->packets = (i + 1) * total_packs / ep->nurbs
663 - i * total_packs / ep->nurbs;
664 u->buffer_size = maxsize * u->packets;
665
666 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
667 u->packets++; /* for transfer delimiter */
668 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
669 if (!u->urb)
670 goto out_of_memory;
671
672 u->urb->transfer_buffer =
673 usb_alloc_coherent(ep->chip->dev, u->buffer_size,
674 GFP_KERNEL, &u->urb->transfer_dma);
675 if (!u->urb->transfer_buffer)
676 goto out_of_memory;
677 u->urb->pipe = ep->pipe;
678 u->urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
679 u->urb->interval = 1 << ep->datainterval;
680 u->urb->context = u;
681 u->urb->complete = snd_complete_urb;
682 INIT_LIST_HEAD(&u->ready_list);
683 }
684
685 return 0;
686
687out_of_memory:
688 release_urbs(ep, 0);
689 return -ENOMEM;
690}
691
692/*
693 * configure a sync endpoint
694 */
695static int sync_ep_set_params(struct snd_usb_endpoint *ep,
696 struct snd_pcm_hw_params *hw_params,
697 struct audioformat *fmt)
698{
699 int i;
700
701 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4,
702 GFP_KERNEL, &ep->sync_dma);
703 if (!ep->syncbuf)
704 return -ENOMEM;
705
706 for (i = 0; i < SYNC_URBS; i++) {
707 struct snd_urb_ctx *u = &ep->urb[i];
708 u->index = i;
709 u->ep = ep;
710 u->packets = 1;
711 u->urb = usb_alloc_urb(1, GFP_KERNEL);
712 if (!u->urb)
713 goto out_of_memory;
714 u->urb->transfer_buffer = ep->syncbuf + i * 4;
715 u->urb->transfer_dma = ep->sync_dma + i * 4;
716 u->urb->transfer_buffer_length = 4;
717 u->urb->pipe = ep->pipe;
718 u->urb->transfer_flags = URB_ISO_ASAP |
719 URB_NO_TRANSFER_DMA_MAP;
720 u->urb->number_of_packets = 1;
721 u->urb->interval = 1 << ep->syncinterval;
722 u->urb->context = u;
723 u->urb->complete = snd_complete_urb;
724 }
725
726 ep->nurbs = SYNC_URBS;
727
728 return 0;
729
730out_of_memory:
731 release_urbs(ep, 0);
732 return -ENOMEM;
733}
734
735/**
736 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
737 *
738 * @ep: the snd_usb_endpoint to configure
739 * @hw_params: the hardware parameters
740 * @fmt: the USB audio format information
741 * @sync_ep: the sync endpoint to use, if any
742 *
743 * Determine the number of URBs to be used on this endpoint.
744 * An endpoint must be configured before it can be started.
745 * An endpoint that is already running can not be reconfigured.
746 */
747int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
748 struct snd_pcm_hw_params *hw_params,
749 struct audioformat *fmt,
750 struct snd_usb_endpoint *sync_ep)
751{
752 int err;
753
754 if (ep->use_count != 0) {
755 snd_printk(KERN_WARNING "Unable to change format on ep #%x: already in use\n",
756 ep->ep_num);
757 return -EBUSY;
758 }
759
760 /* release old buffers, if any */
761 release_urbs(ep, 0);
762
763 ep->datainterval = fmt->datainterval;
764 ep->maxpacksize = fmt->maxpacksize;
765 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
766
767 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL)
768 ep->freqn = get_usb_full_speed_rate(params_rate(hw_params));
769 else
770 ep->freqn = get_usb_high_speed_rate(params_rate(hw_params));
771
772 /* calculate the frequency in 16.16 format */
773 ep->freqm = ep->freqn;
774 ep->freqshift = INT_MIN;
775
776 ep->phase = 0;
777
778 switch (ep->type) {
779 case SND_USB_ENDPOINT_TYPE_DATA:
780 err = data_ep_set_params(ep, hw_params, fmt, sync_ep);
781 break;
782 case SND_USB_ENDPOINT_TYPE_SYNC:
783 err = sync_ep_set_params(ep, hw_params, fmt);
784 break;
785 default:
786 err = -EINVAL;
787 }
788
789 snd_printdd(KERN_DEBUG "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
790 ep->ep_num, ep->type, ep->nurbs, err);
791
792 return err;
793}
794
795/**
796 * snd_usb_endpoint_start: start an snd_usb_endpoint
797 *
798 * @ep: the endpoint to start
799 * @can_sleep: flag indicating whether the operation is executed in
800 * non-atomic context
801 *
802 * A call to this function will increment the use count of the endpoint.
803 * In case it is not already running, the URBs for this endpoint will be
804 * submitted. Otherwise, this function does nothing.
805 *
806 * Must be balanced to calls of snd_usb_endpoint_stop().
807 *
808 * Returns an error if the URB submission failed, 0 in all other cases.
809 */
810int snd_usb_endpoint_start(struct snd_usb_endpoint *ep, int can_sleep)
811{
812 int err;
813 unsigned int i;
814
815 if (ep->chip->shutdown)
816 return -EBADFD;
817
818 /* already running? */
819 if (++ep->use_count != 1)
820 return 0;
821
822 /* just to be sure */
823 deactivate_urbs(ep, 0, can_sleep);
824 if (can_sleep)
825 wait_clear_urbs(ep);
826
827 ep->active_mask = 0;
828 ep->unlink_mask = 0;
829 ep->phase = 0;
830
831 /*
832 * If this endpoint has a data endpoint as implicit feedback source,
833 * don't start the urbs here. Instead, mark them all as available,
834 * wait for the record urbs to return and queue the playback urbs
835 * from that context.
836 */
837
838 set_bit(EP_FLAG_RUNNING, &ep->flags);
839
840 if (snd_usb_endpoint_implict_feedback_sink(ep)) {
841 for (i = 0; i < ep->nurbs; i++) {
842 struct snd_urb_ctx *ctx = ep->urb + i;
843 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
844 }
845
846 return 0;
847 }
848
849 for (i = 0; i < ep->nurbs; i++) {
850 struct urb *urb = ep->urb[i].urb;
851
852 if (snd_BUG_ON(!urb))
853 goto __error;
854
855 if (usb_pipeout(ep->pipe)) {
856 prepare_outbound_urb(ep, urb->context);
857 } else {
858 prepare_inbound_urb(ep, urb->context);
859 }
860
861 err = usb_submit_urb(urb, GFP_ATOMIC);
862 if (err < 0) {
863 snd_printk(KERN_ERR "cannot submit urb %d, error %d: %s\n",
864 i, err, usb_error_string(err));
865 goto __error;
866 }
867 set_bit(i, &ep->active_mask);
868 }
869
870 return 0;
871
872__error:
873 clear_bit(EP_FLAG_RUNNING, &ep->flags);
874 ep->use_count--;
875 deactivate_urbs(ep, 0, 0);
876 return -EPIPE;
877}
878
879/**
880 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
881 *
882 * @ep: the endpoint to stop (may be NULL)
883 *
884 * A call to this function will decrement the use count of the endpoint.
885 * In case the last user has requested the endpoint stop, the URBs will
886 * actually be deactivated.
887 *
888 * Must be balanced to calls of snd_usb_endpoint_start().
889 */
890void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep,
891 int force, int can_sleep, int wait)
892{
893 if (!ep)
894 return;
895
896 if (snd_BUG_ON(ep->use_count == 0))
897 return;
898
899 if (--ep->use_count == 0) {
900 deactivate_urbs(ep, force, can_sleep);
901 ep->data_subs = NULL;
902 ep->sync_slave = NULL;
903 ep->retire_data_urb = NULL;
904 ep->prepare_data_urb = NULL;
905
906 if (wait)
907 wait_clear_urbs(ep);
908 }
909}
910
911/**
912 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
913 *
914 * @ep: the endpoint to deactivate
915 *
916 * If the endpoint is not currently in use, this functions will select the
917 * alternate interface setting 0 for the interface of this endpoint.
918 *
919 * In case of any active users, this functions does nothing.
920 *
921 * Returns an error if usb_set_interface() failed, 0 in all other
922 * cases.
923 */
924int snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep)
925{
926 if (!ep)
927 return -EINVAL;
928
929 deactivate_urbs(ep, 1, 1);
930 wait_clear_urbs(ep);
931
932 if (ep->use_count != 0)
933 return 0;
934
935 clear_bit(EP_FLAG_ACTIVATED, &ep->flags);
936
937 return 0;
938}
939
940/**
941 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
942 *
943 * @ep: the list header of the endpoint to free
944 *
945 * This function does not care for the endpoint's use count but will tear
946 * down all the streaming URBs immediately and free all resources.
947 */
948void snd_usb_endpoint_free(struct list_head *head)
949{
950 struct snd_usb_endpoint *ep;
951
952 ep = list_entry(head, struct snd_usb_endpoint, list);
953 release_urbs(ep, 1);
954 kfree(ep);
955}
956
957/**
958 * snd_usb_handle_sync_urb: parse an USB sync packet
959 *
960 * @ep: the endpoint to handle the packet
961 * @sender: the sending endpoint
962 * @urb: the received packet
963 *
964 * This function is called from the context of an endpoint that received
965 * the packet and is used to let another endpoint object handle the payload.
966 */
967void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
968 struct snd_usb_endpoint *sender,
969 const struct urb *urb)
970{
971 int shift;
972 unsigned int f;
973 unsigned long flags;
974
975 snd_BUG_ON(ep == sender);
976
977 /*
978 * In case the endpoint is operating in implicit feedback mode, prepare
979 * a new outbound URB that has the same layout as the received packet
980 * and add it to the list of pending urbs. queue_pending_output_urbs()
981 * will take care of them later.
982 */
983 if (snd_usb_endpoint_implict_feedback_sink(ep) &&
984 ep->use_count != 0) {
985
986 /* implicit feedback case */
987 int i, bytes = 0;
988 struct snd_urb_ctx *in_ctx;
989 struct snd_usb_packet_info *out_packet;
990
991 in_ctx = urb->context;
992
993 /* Count overall packet size */
994 for (i = 0; i < in_ctx->packets; i++)
995 if (urb->iso_frame_desc[i].status == 0)
996 bytes += urb->iso_frame_desc[i].actual_length;
997
998 /*
999 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1000 * streaming once it received a 0-byte OUT URB
1001 */
1002 if (bytes == 0)
1003 return;
1004
1005 spin_lock_irqsave(&ep->lock, flags);
1006 out_packet = ep->next_packet + ep->next_packet_write_pos;
1007
1008 /*
1009 * Iterate through the inbound packet and prepare the lengths
1010 * for the output packet. The OUT packet we are about to send
1011 * will have the same amount of payload bytes than the IN
1012 * packet we just received.
1013 */
1014
1015 out_packet->packets = in_ctx->packets;
1016 for (i = 0; i < in_ctx->packets; i++) {
1017 if (urb->iso_frame_desc[i].status == 0)
1018 out_packet->packet_size[i] =
1019 urb->iso_frame_desc[i].actual_length / ep->stride;
1020 else
1021 out_packet->packet_size[i] = 0;
1022 }
1023
1024 ep->next_packet_write_pos++;
1025 ep->next_packet_write_pos %= MAX_URBS;
1026 spin_unlock_irqrestore(&ep->lock, flags);
1027 queue_pending_output_urbs(ep);
1028
1029 return;
1030 }
1031
1032 /*
1033 * process after playback sync complete
1034 *
1035 * Full speed devices report feedback values in 10.14 format as samples
1036 * per frame, high speed devices in 16.16 format as samples per
1037 * microframe.
1038 *
1039 * Because the Audio Class 1 spec was written before USB 2.0, many high
1040 * speed devices use a wrong interpretation, some others use an
1041 * entirely different format.
1042 *
1043 * Therefore, we cannot predict what format any particular device uses
1044 * and must detect it automatically.
1045 */
1046
1047 if (urb->iso_frame_desc[0].status != 0 ||
1048 urb->iso_frame_desc[0].actual_length < 3)
1049 return;
1050
1051 f = le32_to_cpup(urb->transfer_buffer);
1052 if (urb->iso_frame_desc[0].actual_length == 3)
1053 f &= 0x00ffffff;
1054 else
1055 f &= 0x0fffffff;
1056
1057 if (f == 0)
1058 return;
1059
1060 if (unlikely(ep->freqshift == INT_MIN)) {
1061 /*
1062 * The first time we see a feedback value, determine its format
1063 * by shifting it left or right until it matches the nominal
1064 * frequency value. This assumes that the feedback does not
1065 * differ from the nominal value more than +50% or -25%.
1066 */
1067 shift = 0;
1068 while (f < ep->freqn - ep->freqn / 4) {
1069 f <<= 1;
1070 shift++;
1071 }
1072 while (f > ep->freqn + ep->freqn / 2) {
1073 f >>= 1;
1074 shift--;
1075 }
1076 ep->freqshift = shift;
1077 } else if (ep->freqshift >= 0)
1078 f <<= ep->freqshift;
1079 else
1080 f >>= -ep->freqshift;
1081
1082 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1083 /*
1084 * If the frequency looks valid, set it.
1085 * This value is referred to in prepare_playback_urb().
1086 */
1087 spin_lock_irqsave(&ep->lock, flags);
1088 ep->freqm = f;
1089 spin_unlock_irqrestore(&ep->lock, flags);
1090 } else {
1091 /*
1092 * Out of range; maybe the shift value is wrong.
1093 * Reset it so that we autodetect again the next time.
1094 */
1095 ep->freqshift = INT_MIN;
1096 }
1097}
1098