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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 "clock.h"
22#include "quirks.h"
23
24enum {
25 EP_STATE_STOPPED,
26 EP_STATE_RUNNING,
27 EP_STATE_STOPPING,
28};
29
30/* interface refcounting */
31struct snd_usb_iface_ref {
32 unsigned char iface;
33 bool need_setup;
34 int opened;
35 struct list_head list;
36};
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
121static inline bool ep_state_running(struct snd_usb_endpoint *ep)
122{
123 return atomic_read(&ep->state) == EP_STATE_RUNNING;
124}
125
126static inline bool ep_state_update(struct snd_usb_endpoint *ep, int old, int new)
127{
128 return atomic_cmpxchg(&ep->state, old, new) == old;
129}
130
131/**
132 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
133 *
134 * @ep: The snd_usb_endpoint
135 *
136 * Determine whether an endpoint is driven by an implicit feedback
137 * data endpoint source.
138 */
139int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
140{
141 return ep->implicit_fb_sync && usb_pipeout(ep->pipe);
142}
143
144/*
145 * Return the number of samples to be sent in the next packet
146 * for streaming based on information derived from sync endpoints
147 *
148 * This won't be used for implicit feedback which takes the packet size
149 * returned from the sync source
150 */
151static int slave_next_packet_size(struct snd_usb_endpoint *ep)
152{
153 unsigned long flags;
154 int ret;
155
156 if (ep->fill_max)
157 return ep->maxframesize;
158
159 spin_lock_irqsave(&ep->lock, flags);
160 ep->phase = (ep->phase & 0xffff)
161 + (ep->freqm << ep->datainterval);
162 ret = min(ep->phase >> 16, ep->maxframesize);
163 spin_unlock_irqrestore(&ep->lock, flags);
164
165 return ret;
166}
167
168/*
169 * Return the number of samples to be sent in the next packet
170 * for adaptive and synchronous endpoints
171 */
172static int next_packet_size(struct snd_usb_endpoint *ep)
173{
174 int ret;
175
176 if (ep->fill_max)
177 return ep->maxframesize;
178
179 ep->sample_accum += ep->sample_rem;
180 if (ep->sample_accum >= ep->pps) {
181 ep->sample_accum -= ep->pps;
182 ret = ep->packsize[1];
183 } else {
184 ret = ep->packsize[0];
185 }
186
187 return ret;
188}
189
190/*
191 * snd_usb_endpoint_next_packet_size: Return the number of samples to be sent
192 * in the next packet
193 */
194int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep,
195 struct snd_urb_ctx *ctx, int idx)
196{
197 if (ctx->packet_size[idx])
198 return ctx->packet_size[idx];
199 else if (ep->sync_source)
200 return slave_next_packet_size(ep);
201 else
202 return next_packet_size(ep);
203}
204
205static void call_retire_callback(struct snd_usb_endpoint *ep,
206 struct urb *urb)
207{
208 struct snd_usb_substream *data_subs;
209
210 data_subs = READ_ONCE(ep->data_subs);
211 if (data_subs && ep->retire_data_urb)
212 ep->retire_data_urb(data_subs, urb);
213}
214
215static void retire_outbound_urb(struct snd_usb_endpoint *ep,
216 struct snd_urb_ctx *urb_ctx)
217{
218 call_retire_callback(ep, urb_ctx->urb);
219}
220
221static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
222 struct snd_usb_endpoint *sender,
223 const struct urb *urb);
224
225static void retire_inbound_urb(struct snd_usb_endpoint *ep,
226 struct snd_urb_ctx *urb_ctx)
227{
228 struct urb *urb = urb_ctx->urb;
229 struct snd_usb_endpoint *sync_sink;
230
231 if (unlikely(ep->skip_packets > 0)) {
232 ep->skip_packets--;
233 return;
234 }
235
236 sync_sink = READ_ONCE(ep->sync_sink);
237 if (sync_sink)
238 snd_usb_handle_sync_urb(sync_sink, ep, urb);
239
240 call_retire_callback(ep, urb);
241}
242
243static void prepare_silent_urb(struct snd_usb_endpoint *ep,
244 struct snd_urb_ctx *ctx)
245{
246 struct urb *urb = ctx->urb;
247 unsigned int offs = 0;
248 unsigned int extra = 0;
249 __le32 packet_length;
250 int i;
251
252 /* For tx_length_quirk, put packet length at start of packet */
253 if (ep->chip->tx_length_quirk)
254 extra = sizeof(packet_length);
255
256 for (i = 0; i < ctx->packets; ++i) {
257 unsigned int offset;
258 unsigned int length;
259 int counts;
260
261 counts = snd_usb_endpoint_next_packet_size(ep, ctx, i);
262 length = counts * ep->stride; /* number of silent bytes */
263 offset = offs * ep->stride + extra * i;
264 urb->iso_frame_desc[i].offset = offset;
265 urb->iso_frame_desc[i].length = length + extra;
266 if (extra) {
267 packet_length = cpu_to_le32(length);
268 memcpy(urb->transfer_buffer + offset,
269 &packet_length, sizeof(packet_length));
270 }
271 memset(urb->transfer_buffer + offset + extra,
272 ep->silence_value, length);
273 offs += counts;
274 }
275
276 urb->number_of_packets = ctx->packets;
277 urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
278 ctx->queued = 0;
279}
280
281/*
282 * Prepare a PLAYBACK urb for submission to the bus.
283 */
284static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
285 struct snd_urb_ctx *ctx)
286{
287 struct urb *urb = ctx->urb;
288 unsigned char *cp = urb->transfer_buffer;
289 struct snd_usb_substream *data_subs;
290
291 urb->dev = ep->chip->dev; /* we need to set this at each time */
292
293 switch (ep->type) {
294 case SND_USB_ENDPOINT_TYPE_DATA:
295 data_subs = READ_ONCE(ep->data_subs);
296 if (data_subs && ep->prepare_data_urb)
297 ep->prepare_data_urb(data_subs, urb);
298 else /* no data provider, so send silence */
299 prepare_silent_urb(ep, ctx);
300 break;
301
302 case SND_USB_ENDPOINT_TYPE_SYNC:
303 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
304 /*
305 * fill the length and offset of each urb descriptor.
306 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
307 */
308 urb->iso_frame_desc[0].length = 4;
309 urb->iso_frame_desc[0].offset = 0;
310 cp[0] = ep->freqn;
311 cp[1] = ep->freqn >> 8;
312 cp[2] = ep->freqn >> 16;
313 cp[3] = ep->freqn >> 24;
314 } else {
315 /*
316 * fill the length and offset of each urb descriptor.
317 * the fixed 10.14 frequency is passed through the pipe.
318 */
319 urb->iso_frame_desc[0].length = 3;
320 urb->iso_frame_desc[0].offset = 0;
321 cp[0] = ep->freqn >> 2;
322 cp[1] = ep->freqn >> 10;
323 cp[2] = ep->freqn >> 18;
324 }
325
326 break;
327 }
328}
329
330/*
331 * Prepare a CAPTURE or SYNC urb for submission to the bus.
332 */
333static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep,
334 struct snd_urb_ctx *urb_ctx)
335{
336 int i, offs;
337 struct urb *urb = urb_ctx->urb;
338
339 urb->dev = ep->chip->dev; /* we need to set this at each time */
340
341 switch (ep->type) {
342 case SND_USB_ENDPOINT_TYPE_DATA:
343 offs = 0;
344 for (i = 0; i < urb_ctx->packets; i++) {
345 urb->iso_frame_desc[i].offset = offs;
346 urb->iso_frame_desc[i].length = ep->curpacksize;
347 offs += ep->curpacksize;
348 }
349
350 urb->transfer_buffer_length = offs;
351 urb->number_of_packets = urb_ctx->packets;
352 break;
353
354 case SND_USB_ENDPOINT_TYPE_SYNC:
355 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
356 urb->iso_frame_desc[0].offset = 0;
357 break;
358 }
359}
360
361/* notify an error as XRUN to the assigned PCM data substream */
362static void notify_xrun(struct snd_usb_endpoint *ep)
363{
364 struct snd_usb_substream *data_subs;
365
366 data_subs = READ_ONCE(ep->data_subs);
367 if (data_subs && data_subs->pcm_substream)
368 snd_pcm_stop_xrun(data_subs->pcm_substream);
369}
370
371static struct snd_usb_packet_info *
372next_packet_fifo_enqueue(struct snd_usb_endpoint *ep)
373{
374 struct snd_usb_packet_info *p;
375
376 p = ep->next_packet + (ep->next_packet_head + ep->next_packet_queued) %
377 ARRAY_SIZE(ep->next_packet);
378 ep->next_packet_queued++;
379 return p;
380}
381
382static struct snd_usb_packet_info *
383next_packet_fifo_dequeue(struct snd_usb_endpoint *ep)
384{
385 struct snd_usb_packet_info *p;
386
387 p = ep->next_packet + ep->next_packet_head;
388 ep->next_packet_head++;
389 ep->next_packet_head %= ARRAY_SIZE(ep->next_packet);
390 ep->next_packet_queued--;
391 return p;
392}
393
394/*
395 * Send output urbs that have been prepared previously. URBs are dequeued
396 * from ep->ready_playback_urbs and in case there aren't any available
397 * or there are no packets that have been prepared, this function does
398 * nothing.
399 *
400 * The reason why the functionality of sending and preparing URBs is separated
401 * is that host controllers don't guarantee the order in which they return
402 * inbound and outbound packets to their submitters.
403 *
404 * This function is only used for implicit feedback endpoints. For endpoints
405 * driven by dedicated sync endpoints, URBs are immediately re-submitted
406 * from their completion handler.
407 */
408static void queue_pending_output_urbs(struct snd_usb_endpoint *ep)
409{
410 while (ep_state_running(ep)) {
411
412 unsigned long flags;
413 struct snd_usb_packet_info *packet;
414 struct snd_urb_ctx *ctx = NULL;
415 int err, i;
416
417 spin_lock_irqsave(&ep->lock, flags);
418 if (ep->next_packet_queued > 0 &&
419 !list_empty(&ep->ready_playback_urbs)) {
420 /* take URB out of FIFO */
421 ctx = list_first_entry(&ep->ready_playback_urbs,
422 struct snd_urb_ctx, ready_list);
423 list_del_init(&ctx->ready_list);
424
425 packet = next_packet_fifo_dequeue(ep);
426 }
427 spin_unlock_irqrestore(&ep->lock, flags);
428
429 if (ctx == NULL)
430 return;
431
432 /* copy over the length information */
433 for (i = 0; i < packet->packets; i++)
434 ctx->packet_size[i] = packet->packet_size[i];
435
436 /* call the data handler to fill in playback data */
437 prepare_outbound_urb(ep, ctx);
438
439 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
440 if (err < 0) {
441 usb_audio_err(ep->chip,
442 "Unable to submit urb #%d: %d at %s\n",
443 ctx->index, err, __func__);
444 notify_xrun(ep);
445 return;
446 }
447
448 set_bit(ctx->index, &ep->active_mask);
449 }
450}
451
452/*
453 * complete callback for urbs
454 */
455static void snd_complete_urb(struct urb *urb)
456{
457 struct snd_urb_ctx *ctx = urb->context;
458 struct snd_usb_endpoint *ep = ctx->ep;
459 unsigned long flags;
460 int err;
461
462 if (unlikely(urb->status == -ENOENT || /* unlinked */
463 urb->status == -ENODEV || /* device removed */
464 urb->status == -ECONNRESET || /* unlinked */
465 urb->status == -ESHUTDOWN)) /* device disabled */
466 goto exit_clear;
467 /* device disconnected */
468 if (unlikely(atomic_read(&ep->chip->shutdown)))
469 goto exit_clear;
470
471 if (unlikely(!ep_state_running(ep)))
472 goto exit_clear;
473
474 if (usb_pipeout(ep->pipe)) {
475 retire_outbound_urb(ep, ctx);
476 /* can be stopped during retire callback */
477 if (unlikely(!ep_state_running(ep)))
478 goto exit_clear;
479
480 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
481 spin_lock_irqsave(&ep->lock, flags);
482 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
483 clear_bit(ctx->index, &ep->active_mask);
484 spin_unlock_irqrestore(&ep->lock, flags);
485 queue_pending_output_urbs(ep);
486 return;
487 }
488
489 prepare_outbound_urb(ep, ctx);
490 /* can be stopped during prepare callback */
491 if (unlikely(!ep_state_running(ep)))
492 goto exit_clear;
493 } else {
494 retire_inbound_urb(ep, ctx);
495 /* can be stopped during retire callback */
496 if (unlikely(!ep_state_running(ep)))
497 goto exit_clear;
498
499 prepare_inbound_urb(ep, ctx);
500 }
501
502 err = usb_submit_urb(urb, GFP_ATOMIC);
503 if (err == 0)
504 return;
505
506 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
507 notify_xrun(ep);
508
509exit_clear:
510 clear_bit(ctx->index, &ep->active_mask);
511}
512
513/*
514 * Find or create a refcount object for the given interface
515 *
516 * The objects are released altogether in snd_usb_endpoint_free_all()
517 */
518static struct snd_usb_iface_ref *
519iface_ref_find(struct snd_usb_audio *chip, int iface)
520{
521 struct snd_usb_iface_ref *ip;
522
523 list_for_each_entry(ip, &chip->iface_ref_list, list)
524 if (ip->iface == iface)
525 return ip;
526
527 ip = kzalloc(sizeof(*ip), GFP_KERNEL);
528 if (!ip)
529 return NULL;
530 ip->iface = iface;
531 list_add_tail(&ip->list, &chip->iface_ref_list);
532 return ip;
533}
534
535/*
536 * Get the existing endpoint object corresponding EP
537 * Returns NULL if not present.
538 */
539struct snd_usb_endpoint *
540snd_usb_get_endpoint(struct snd_usb_audio *chip, int ep_num)
541{
542 struct snd_usb_endpoint *ep;
543
544 list_for_each_entry(ep, &chip->ep_list, list) {
545 if (ep->ep_num == ep_num)
546 return ep;
547 }
548
549 return NULL;
550}
551
552#define ep_type_name(type) \
553 (type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync")
554
555/**
556 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
557 *
558 * @chip: The chip
559 * @ep_num: The number of the endpoint to use
560 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
561 *
562 * If the requested endpoint has not been added to the given chip before,
563 * a new instance is created.
564 *
565 * Returns zero on success or a negative error code.
566 *
567 * New endpoints will be added to chip->ep_list and freed by
568 * calling snd_usb_endpoint_free_all().
569 *
570 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
571 * bNumEndpoints > 1 beforehand.
572 */
573int snd_usb_add_endpoint(struct snd_usb_audio *chip, int ep_num, int type)
574{
575 struct snd_usb_endpoint *ep;
576 bool is_playback;
577
578 ep = snd_usb_get_endpoint(chip, ep_num);
579 if (ep)
580 return 0;
581
582 usb_audio_dbg(chip, "Creating new %s endpoint #%x\n",
583 ep_type_name(type),
584 ep_num);
585 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
586 if (!ep)
587 return -ENOMEM;
588
589 ep->chip = chip;
590 spin_lock_init(&ep->lock);
591 ep->type = type;
592 ep->ep_num = ep_num;
593 INIT_LIST_HEAD(&ep->ready_playback_urbs);
594
595 is_playback = ((ep_num & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT);
596 ep_num &= USB_ENDPOINT_NUMBER_MASK;
597 if (is_playback)
598 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
599 else
600 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
601
602 list_add_tail(&ep->list, &chip->ep_list);
603 return 0;
604}
605
606/* Set up syncinterval and maxsyncsize for a sync EP */
607static void endpoint_set_syncinterval(struct snd_usb_audio *chip,
608 struct snd_usb_endpoint *ep)
609{
610 struct usb_host_interface *alts;
611 struct usb_endpoint_descriptor *desc;
612
613 alts = snd_usb_get_host_interface(chip, ep->iface, ep->altsetting);
614 if (!alts)
615 return;
616
617 desc = get_endpoint(alts, ep->ep_idx);
618 if (desc->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
619 desc->bRefresh >= 1 && desc->bRefresh <= 9)
620 ep->syncinterval = desc->bRefresh;
621 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
622 ep->syncinterval = 1;
623 else if (desc->bInterval >= 1 && desc->bInterval <= 16)
624 ep->syncinterval = desc->bInterval - 1;
625 else
626 ep->syncinterval = 3;
627
628 ep->syncmaxsize = le16_to_cpu(desc->wMaxPacketSize);
629}
630
631static bool endpoint_compatible(struct snd_usb_endpoint *ep,
632 const struct audioformat *fp,
633 const struct snd_pcm_hw_params *params)
634{
635 if (!ep->opened)
636 return false;
637 if (ep->cur_audiofmt != fp)
638 return false;
639 if (ep->cur_rate != params_rate(params) ||
640 ep->cur_format != params_format(params) ||
641 ep->cur_period_frames != params_period_size(params) ||
642 ep->cur_buffer_periods != params_periods(params))
643 return false;
644 return true;
645}
646
647/*
648 * Check whether the given fp and hw params are compatible with the current
649 * setup of the target EP for implicit feedback sync
650 */
651bool snd_usb_endpoint_compatible(struct snd_usb_audio *chip,
652 struct snd_usb_endpoint *ep,
653 const struct audioformat *fp,
654 const struct snd_pcm_hw_params *params)
655{
656 bool ret;
657
658 mutex_lock(&chip->mutex);
659 ret = endpoint_compatible(ep, fp, params);
660 mutex_unlock(&chip->mutex);
661 return ret;
662}
663
664/*
665 * snd_usb_endpoint_open: Open the endpoint
666 *
667 * Called from hw_params to assign the endpoint to the substream.
668 * It's reference-counted, and only the first opener is allowed to set up
669 * arbitrary parameters. The later opener must be compatible with the
670 * former opened parameters.
671 * The endpoint needs to be closed via snd_usb_endpoint_close() later.
672 *
673 * Note that this function doesn't configure the endpoint. The substream
674 * needs to set it up later via snd_usb_endpoint_configure().
675 */
676struct snd_usb_endpoint *
677snd_usb_endpoint_open(struct snd_usb_audio *chip,
678 const struct audioformat *fp,
679 const struct snd_pcm_hw_params *params,
680 bool is_sync_ep)
681{
682 struct snd_usb_endpoint *ep;
683 int ep_num = is_sync_ep ? fp->sync_ep : fp->endpoint;
684
685 mutex_lock(&chip->mutex);
686 ep = snd_usb_get_endpoint(chip, ep_num);
687 if (!ep) {
688 usb_audio_err(chip, "Cannot find EP 0x%x to open\n", ep_num);
689 goto unlock;
690 }
691
692 if (!ep->opened) {
693 if (is_sync_ep) {
694 ep->iface = fp->sync_iface;
695 ep->altsetting = fp->sync_altsetting;
696 ep->ep_idx = fp->sync_ep_idx;
697 } else {
698 ep->iface = fp->iface;
699 ep->altsetting = fp->altsetting;
700 ep->ep_idx = fp->ep_idx;
701 }
702 usb_audio_dbg(chip, "Open EP 0x%x, iface=%d:%d, idx=%d\n",
703 ep_num, ep->iface, ep->altsetting, ep->ep_idx);
704
705 ep->iface_ref = iface_ref_find(chip, ep->iface);
706 if (!ep->iface_ref) {
707 ep = NULL;
708 goto unlock;
709 }
710
711 ep->cur_audiofmt = fp;
712 ep->cur_channels = fp->channels;
713 ep->cur_rate = params_rate(params);
714 ep->cur_format = params_format(params);
715 ep->cur_frame_bytes = snd_pcm_format_physical_width(ep->cur_format) *
716 ep->cur_channels / 8;
717 ep->cur_period_frames = params_period_size(params);
718 ep->cur_period_bytes = ep->cur_period_frames * ep->cur_frame_bytes;
719 ep->cur_buffer_periods = params_periods(params);
720
721 if (ep->type == SND_USB_ENDPOINT_TYPE_SYNC)
722 endpoint_set_syncinterval(chip, ep);
723
724 ep->implicit_fb_sync = fp->implicit_fb;
725 ep->need_setup = true;
726
727 usb_audio_dbg(chip, " channels=%d, rate=%d, format=%s, period_bytes=%d, periods=%d, implicit_fb=%d\n",
728 ep->cur_channels, ep->cur_rate,
729 snd_pcm_format_name(ep->cur_format),
730 ep->cur_period_bytes, ep->cur_buffer_periods,
731 ep->implicit_fb_sync);
732
733 } else {
734 if (WARN_ON(!ep->iface_ref)) {
735 ep = NULL;
736 goto unlock;
737 }
738
739 if (!endpoint_compatible(ep, fp, params)) {
740 usb_audio_err(chip, "Incompatible EP setup for 0x%x\n",
741 ep_num);
742 ep = NULL;
743 goto unlock;
744 }
745
746 usb_audio_dbg(chip, "Reopened EP 0x%x (count %d)\n",
747 ep_num, ep->opened);
748 }
749
750 if (!ep->iface_ref->opened++)
751 ep->iface_ref->need_setup = true;
752
753 ep->opened++;
754
755 unlock:
756 mutex_unlock(&chip->mutex);
757 return ep;
758}
759
760/*
761 * snd_usb_endpoint_set_sync: Link data and sync endpoints
762 *
763 * Pass NULL to sync_ep to unlink again
764 */
765void snd_usb_endpoint_set_sync(struct snd_usb_audio *chip,
766 struct snd_usb_endpoint *data_ep,
767 struct snd_usb_endpoint *sync_ep)
768{
769 data_ep->sync_source = sync_ep;
770}
771
772/*
773 * Set data endpoint callbacks and the assigned data stream
774 *
775 * Called at PCM trigger and cleanups.
776 * Pass NULL to deactivate each callback.
777 */
778void snd_usb_endpoint_set_callback(struct snd_usb_endpoint *ep,
779 void (*prepare)(struct snd_usb_substream *subs,
780 struct urb *urb),
781 void (*retire)(struct snd_usb_substream *subs,
782 struct urb *urb),
783 struct snd_usb_substream *data_subs)
784{
785 ep->prepare_data_urb = prepare;
786 ep->retire_data_urb = retire;
787 WRITE_ONCE(ep->data_subs, data_subs);
788}
789
790static int endpoint_set_interface(struct snd_usb_audio *chip,
791 struct snd_usb_endpoint *ep,
792 bool set)
793{
794 int altset = set ? ep->altsetting : 0;
795 int err;
796
797 usb_audio_dbg(chip, "Setting usb interface %d:%d for EP 0x%x\n",
798 ep->iface, altset, ep->ep_num);
799 err = usb_set_interface(chip->dev, ep->iface, altset);
800 if (err < 0) {
801 usb_audio_err(chip, "%d:%d: usb_set_interface failed (%d)\n",
802 ep->iface, altset, err);
803 return err;
804 }
805
806 snd_usb_set_interface_quirk(chip);
807 return 0;
808}
809
810/*
811 * snd_usb_endpoint_close: Close the endpoint
812 *
813 * Unreference the already opened endpoint via snd_usb_endpoint_open().
814 */
815void snd_usb_endpoint_close(struct snd_usb_audio *chip,
816 struct snd_usb_endpoint *ep)
817{
818 mutex_lock(&chip->mutex);
819 usb_audio_dbg(chip, "Closing EP 0x%x (count %d)\n",
820 ep->ep_num, ep->opened);
821
822 if (!--ep->iface_ref->opened)
823 endpoint_set_interface(chip, ep, false);
824
825 if (!--ep->opened) {
826 ep->iface = 0;
827 ep->altsetting = 0;
828 ep->cur_audiofmt = NULL;
829 ep->cur_rate = 0;
830 ep->iface_ref = NULL;
831 usb_audio_dbg(chip, "EP 0x%x closed\n", ep->ep_num);
832 }
833 mutex_unlock(&chip->mutex);
834}
835
836/* Prepare for suspening EP, called from the main suspend handler */
837void snd_usb_endpoint_suspend(struct snd_usb_endpoint *ep)
838{
839 ep->need_setup = true;
840 if (ep->iface_ref)
841 ep->iface_ref->need_setup = true;
842}
843
844/*
845 * wait until all urbs are processed.
846 */
847static int wait_clear_urbs(struct snd_usb_endpoint *ep)
848{
849 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
850 int alive;
851
852 if (atomic_read(&ep->state) != EP_STATE_STOPPING)
853 return 0;
854
855 do {
856 alive = bitmap_weight(&ep->active_mask, ep->nurbs);
857 if (!alive)
858 break;
859
860 schedule_timeout_uninterruptible(1);
861 } while (time_before(jiffies, end_time));
862
863 if (alive)
864 usb_audio_err(ep->chip,
865 "timeout: still %d active urbs on EP #%x\n",
866 alive, ep->ep_num);
867
868 if (ep_state_update(ep, EP_STATE_STOPPING, EP_STATE_STOPPED)) {
869 ep->sync_sink = NULL;
870 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
871 }
872
873 return 0;
874}
875
876/* sync the pending stop operation;
877 * this function itself doesn't trigger the stop operation
878 */
879void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
880{
881 if (ep)
882 wait_clear_urbs(ep);
883}
884
885/*
886 * Stop active urbs
887 *
888 * This function moves the EP to STOPPING state if it's being RUNNING.
889 */
890static int stop_urbs(struct snd_usb_endpoint *ep, bool force)
891{
892 unsigned int i;
893
894 if (!force && atomic_read(&ep->running))
895 return -EBUSY;
896
897 if (!ep_state_update(ep, EP_STATE_RUNNING, EP_STATE_STOPPING))
898 return 0;
899
900 INIT_LIST_HEAD(&ep->ready_playback_urbs);
901 ep->next_packet_head = 0;
902 ep->next_packet_queued = 0;
903
904 for (i = 0; i < ep->nurbs; i++) {
905 if (test_bit(i, &ep->active_mask)) {
906 if (!test_and_set_bit(i, &ep->unlink_mask)) {
907 struct urb *u = ep->urb[i].urb;
908 usb_unlink_urb(u);
909 }
910 }
911 }
912
913 return 0;
914}
915
916/*
917 * release an endpoint's urbs
918 */
919static int release_urbs(struct snd_usb_endpoint *ep, bool force)
920{
921 int i, err;
922
923 /* route incoming urbs to nirvana */
924 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
925
926 /* stop and unlink urbs */
927 err = stop_urbs(ep, force);
928 if (err)
929 return err;
930
931 wait_clear_urbs(ep);
932
933 for (i = 0; i < ep->nurbs; i++)
934 release_urb_ctx(&ep->urb[i]);
935
936 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
937 ep->syncbuf, ep->sync_dma);
938
939 ep->syncbuf = NULL;
940 ep->nurbs = 0;
941 return 0;
942}
943
944/*
945 * configure a data endpoint
946 */
947static int data_ep_set_params(struct snd_usb_endpoint *ep)
948{
949 struct snd_usb_audio *chip = ep->chip;
950 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
951 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
952 unsigned int max_urbs, i;
953 const struct audioformat *fmt = ep->cur_audiofmt;
954 int frame_bits = ep->cur_frame_bytes * 8;
955 int tx_length_quirk = (chip->tx_length_quirk &&
956 usb_pipeout(ep->pipe));
957
958 usb_audio_dbg(chip, "Setting params for data EP 0x%x, pipe 0x%x\n",
959 ep->ep_num, ep->pipe);
960
961 if (ep->cur_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
962 /*
963 * When operating in DSD DOP mode, the size of a sample frame
964 * in hardware differs from the actual physical format width
965 * because we need to make room for the DOP markers.
966 */
967 frame_bits += ep->cur_channels << 3;
968 }
969
970 ep->datainterval = fmt->datainterval;
971 ep->stride = frame_bits >> 3;
972
973 switch (ep->cur_format) {
974 case SNDRV_PCM_FORMAT_U8:
975 ep->silence_value = 0x80;
976 break;
977 case SNDRV_PCM_FORMAT_DSD_U8:
978 case SNDRV_PCM_FORMAT_DSD_U16_LE:
979 case SNDRV_PCM_FORMAT_DSD_U32_LE:
980 case SNDRV_PCM_FORMAT_DSD_U16_BE:
981 case SNDRV_PCM_FORMAT_DSD_U32_BE:
982 ep->silence_value = 0x69;
983 break;
984 default:
985 ep->silence_value = 0;
986 }
987
988 /* assume max. frequency is 50% higher than nominal */
989 ep->freqmax = ep->freqn + (ep->freqn >> 1);
990 /* Round up freqmax to nearest integer in order to calculate maximum
991 * packet size, which must represent a whole number of frames.
992 * This is accomplished by adding 0x0.ffff before converting the
993 * Q16.16 format into integer.
994 * In order to accurately calculate the maximum packet size when
995 * the data interval is more than 1 (i.e. ep->datainterval > 0),
996 * multiply by the data interval prior to rounding. For instance,
997 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
998 * frames with a data interval of 1, but 11 (10.25) frames with a
999 * data interval of 2.
1000 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
1001 * maximum datainterval value of 3, at USB full speed, higher for
1002 * USB high speed, noting that ep->freqmax is in units of
1003 * frames per packet in Q16.16 format.)
1004 */
1005 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
1006 (frame_bits >> 3);
1007 if (tx_length_quirk)
1008 maxsize += sizeof(__le32); /* Space for length descriptor */
1009 /* but wMaxPacketSize might reduce this */
1010 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
1011 /* whatever fits into a max. size packet */
1012 unsigned int data_maxsize = maxsize = ep->maxpacksize;
1013
1014 if (tx_length_quirk)
1015 /* Need to remove the length descriptor to calc freq */
1016 data_maxsize -= sizeof(__le32);
1017 ep->freqmax = (data_maxsize / (frame_bits >> 3))
1018 << (16 - ep->datainterval);
1019 }
1020
1021 if (ep->fill_max)
1022 ep->curpacksize = ep->maxpacksize;
1023 else
1024 ep->curpacksize = maxsize;
1025
1026 if (snd_usb_get_speed(chip->dev) != USB_SPEED_FULL) {
1027 packs_per_ms = 8 >> ep->datainterval;
1028 max_packs_per_urb = MAX_PACKS_HS;
1029 } else {
1030 packs_per_ms = 1;
1031 max_packs_per_urb = MAX_PACKS;
1032 }
1033 if (ep->sync_source && !ep->implicit_fb_sync)
1034 max_packs_per_urb = min(max_packs_per_urb,
1035 1U << ep->sync_source->syncinterval);
1036 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
1037
1038 /*
1039 * Capture endpoints need to use small URBs because there's no way
1040 * to tell in advance where the next period will end, and we don't
1041 * want the next URB to complete much after the period ends.
1042 *
1043 * Playback endpoints with implicit sync much use the same parameters
1044 * as their corresponding capture endpoint.
1045 */
1046 if (usb_pipein(ep->pipe) || ep->implicit_fb_sync) {
1047
1048 urb_packs = packs_per_ms;
1049 /*
1050 * Wireless devices can poll at a max rate of once per 4ms.
1051 * For dataintervals less than 5, increase the packet count to
1052 * allow the host controller to use bursting to fill in the
1053 * gaps.
1054 */
1055 if (snd_usb_get_speed(chip->dev) == USB_SPEED_WIRELESS) {
1056 int interval = ep->datainterval;
1057 while (interval < 5) {
1058 urb_packs <<= 1;
1059 ++interval;
1060 }
1061 }
1062 /* make capture URBs <= 1 ms and smaller than a period */
1063 urb_packs = min(max_packs_per_urb, urb_packs);
1064 while (urb_packs > 1 && urb_packs * maxsize >= ep->cur_period_bytes)
1065 urb_packs >>= 1;
1066 ep->nurbs = MAX_URBS;
1067
1068 /*
1069 * Playback endpoints without implicit sync are adjusted so that
1070 * a period fits as evenly as possible in the smallest number of
1071 * URBs. The total number of URBs is adjusted to the size of the
1072 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
1073 */
1074 } else {
1075 /* determine how small a packet can be */
1076 minsize = (ep->freqn >> (16 - ep->datainterval)) *
1077 (frame_bits >> 3);
1078 /* with sync from device, assume it can be 12% lower */
1079 if (ep->sync_source)
1080 minsize -= minsize >> 3;
1081 minsize = max(minsize, 1u);
1082
1083 /* how many packets will contain an entire ALSA period? */
1084 max_packs_per_period = DIV_ROUND_UP(ep->cur_period_bytes, minsize);
1085
1086 /* how many URBs will contain a period? */
1087 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
1088 max_packs_per_urb);
1089 /* how many packets are needed in each URB? */
1090 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
1091
1092 /* limit the number of frames in a single URB */
1093 ep->max_urb_frames = DIV_ROUND_UP(ep->cur_period_frames,
1094 urbs_per_period);
1095
1096 /* try to use enough URBs to contain an entire ALSA buffer */
1097 max_urbs = min((unsigned) MAX_URBS,
1098 MAX_QUEUE * packs_per_ms / urb_packs);
1099 ep->nurbs = min(max_urbs, urbs_per_period * ep->cur_buffer_periods);
1100 }
1101
1102 /* allocate and initialize data urbs */
1103 for (i = 0; i < ep->nurbs; i++) {
1104 struct snd_urb_ctx *u = &ep->urb[i];
1105 u->index = i;
1106 u->ep = ep;
1107 u->packets = urb_packs;
1108 u->buffer_size = maxsize * u->packets;
1109
1110 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
1111 u->packets++; /* for transfer delimiter */
1112 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
1113 if (!u->urb)
1114 goto out_of_memory;
1115
1116 u->urb->transfer_buffer =
1117 usb_alloc_coherent(chip->dev, u->buffer_size,
1118 GFP_KERNEL, &u->urb->transfer_dma);
1119 if (!u->urb->transfer_buffer)
1120 goto out_of_memory;
1121 u->urb->pipe = ep->pipe;
1122 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1123 u->urb->interval = 1 << ep->datainterval;
1124 u->urb->context = u;
1125 u->urb->complete = snd_complete_urb;
1126 INIT_LIST_HEAD(&u->ready_list);
1127 }
1128
1129 /* total buffer bytes of all URBs plus the next queue;
1130 * referred in pcm.c
1131 */
1132 ep->nominal_queue_size = maxsize * urb_packs * (ep->nurbs + 1);
1133 return 0;
1134
1135out_of_memory:
1136 release_urbs(ep, false);
1137 return -ENOMEM;
1138}
1139
1140/*
1141 * configure a sync endpoint
1142 */
1143static int sync_ep_set_params(struct snd_usb_endpoint *ep)
1144{
1145 struct snd_usb_audio *chip = ep->chip;
1146 int i;
1147
1148 usb_audio_dbg(chip, "Setting params for sync EP 0x%x, pipe 0x%x\n",
1149 ep->ep_num, ep->pipe);
1150
1151 ep->syncbuf = usb_alloc_coherent(chip->dev, SYNC_URBS * 4,
1152 GFP_KERNEL, &ep->sync_dma);
1153 if (!ep->syncbuf)
1154 return -ENOMEM;
1155
1156 for (i = 0; i < SYNC_URBS; i++) {
1157 struct snd_urb_ctx *u = &ep->urb[i];
1158 u->index = i;
1159 u->ep = ep;
1160 u->packets = 1;
1161 u->urb = usb_alloc_urb(1, GFP_KERNEL);
1162 if (!u->urb)
1163 goto out_of_memory;
1164 u->urb->transfer_buffer = ep->syncbuf + i * 4;
1165 u->urb->transfer_dma = ep->sync_dma + i * 4;
1166 u->urb->transfer_buffer_length = 4;
1167 u->urb->pipe = ep->pipe;
1168 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1169 u->urb->number_of_packets = 1;
1170 u->urb->interval = 1 << ep->syncinterval;
1171 u->urb->context = u;
1172 u->urb->complete = snd_complete_urb;
1173 }
1174
1175 ep->nurbs = SYNC_URBS;
1176
1177 return 0;
1178
1179out_of_memory:
1180 release_urbs(ep, false);
1181 return -ENOMEM;
1182}
1183
1184/*
1185 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
1186 *
1187 * Determine the number of URBs to be used on this endpoint.
1188 * An endpoint must be configured before it can be started.
1189 * An endpoint that is already running can not be reconfigured.
1190 */
1191static int snd_usb_endpoint_set_params(struct snd_usb_audio *chip,
1192 struct snd_usb_endpoint *ep)
1193{
1194 const struct audioformat *fmt = ep->cur_audiofmt;
1195 int err;
1196
1197 /* release old buffers, if any */
1198 err = release_urbs(ep, false);
1199 if (err < 0)
1200 return err;
1201
1202 ep->datainterval = fmt->datainterval;
1203 ep->maxpacksize = fmt->maxpacksize;
1204 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
1205
1206 if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) {
1207 ep->freqn = get_usb_full_speed_rate(ep->cur_rate);
1208 ep->pps = 1000 >> ep->datainterval;
1209 } else {
1210 ep->freqn = get_usb_high_speed_rate(ep->cur_rate);
1211 ep->pps = 8000 >> ep->datainterval;
1212 }
1213
1214 ep->sample_rem = ep->cur_rate % ep->pps;
1215 ep->packsize[0] = ep->cur_rate / ep->pps;
1216 ep->packsize[1] = (ep->cur_rate + (ep->pps - 1)) / ep->pps;
1217
1218 /* calculate the frequency in 16.16 format */
1219 ep->freqm = ep->freqn;
1220 ep->freqshift = INT_MIN;
1221
1222 ep->phase = 0;
1223
1224 switch (ep->type) {
1225 case SND_USB_ENDPOINT_TYPE_DATA:
1226 err = data_ep_set_params(ep);
1227 break;
1228 case SND_USB_ENDPOINT_TYPE_SYNC:
1229 err = sync_ep_set_params(ep);
1230 break;
1231 default:
1232 err = -EINVAL;
1233 }
1234
1235 usb_audio_dbg(chip, "Set up %d URBS, ret=%d\n", ep->nurbs, err);
1236
1237 if (err < 0)
1238 return err;
1239
1240 /* some unit conversions in runtime */
1241 ep->maxframesize = ep->maxpacksize / ep->cur_frame_bytes;
1242 ep->curframesize = ep->curpacksize / ep->cur_frame_bytes;
1243
1244 return 0;
1245}
1246
1247/*
1248 * snd_usb_endpoint_configure: Configure the endpoint
1249 *
1250 * This function sets up the EP to be fully usable state.
1251 * It's called either from hw_params or prepare callback.
1252 * The function checks need_setup flag, and performs nothing unless needed,
1253 * so it's safe to call this multiple times.
1254 *
1255 * This returns zero if unchanged, 1 if the configuration has changed,
1256 * or a negative error code.
1257 */
1258int snd_usb_endpoint_configure(struct snd_usb_audio *chip,
1259 struct snd_usb_endpoint *ep)
1260{
1261 bool iface_first;
1262 int err = 0;
1263
1264 mutex_lock(&chip->mutex);
1265 if (WARN_ON(!ep->iface_ref))
1266 goto unlock;
1267 if (!ep->need_setup)
1268 goto unlock;
1269
1270 /* If the interface has been already set up, just set EP parameters */
1271 if (!ep->iface_ref->need_setup) {
1272 /* sample rate setup of UAC1 is per endpoint, and we need
1273 * to update at each EP configuration
1274 */
1275 if (ep->cur_audiofmt->protocol == UAC_VERSION_1) {
1276 err = snd_usb_init_sample_rate(chip, ep->cur_audiofmt,
1277 ep->cur_rate);
1278 if (err < 0)
1279 goto unlock;
1280 }
1281 err = snd_usb_endpoint_set_params(chip, ep);
1282 if (err < 0)
1283 goto unlock;
1284 goto done;
1285 }
1286
1287 /* Need to deselect altsetting at first */
1288 endpoint_set_interface(chip, ep, false);
1289
1290 /* Some UAC1 devices (e.g. Yamaha THR10) need the host interface
1291 * to be set up before parameter setups
1292 */
1293 iface_first = ep->cur_audiofmt->protocol == UAC_VERSION_1;
1294 /* Workaround for Sony WALKMAN NW-A45 DAC;
1295 * it requires the interface setup at first like UAC1
1296 */
1297 if (chip->usb_id == USB_ID(0x054c, 0x0b8c))
1298 iface_first = true;
1299 if (iface_first) {
1300 err = endpoint_set_interface(chip, ep, true);
1301 if (err < 0)
1302 goto unlock;
1303 }
1304
1305 err = snd_usb_init_pitch(chip, ep->cur_audiofmt);
1306 if (err < 0)
1307 goto unlock;
1308
1309 err = snd_usb_init_sample_rate(chip, ep->cur_audiofmt, ep->cur_rate);
1310 if (err < 0)
1311 goto unlock;
1312
1313 err = snd_usb_endpoint_set_params(chip, ep);
1314 if (err < 0)
1315 goto unlock;
1316
1317 err = snd_usb_select_mode_quirk(chip, ep->cur_audiofmt);
1318 if (err < 0)
1319 goto unlock;
1320
1321 /* for UAC2/3, enable the interface altset here at last */
1322 if (!iface_first) {
1323 err = endpoint_set_interface(chip, ep, true);
1324 if (err < 0)
1325 goto unlock;
1326 }
1327
1328 ep->iface_ref->need_setup = false;
1329
1330 done:
1331 ep->need_setup = false;
1332 err = 1;
1333
1334unlock:
1335 mutex_unlock(&chip->mutex);
1336 return err;
1337}
1338
1339/**
1340 * snd_usb_endpoint_start: start an snd_usb_endpoint
1341 *
1342 * @ep: the endpoint to start
1343 *
1344 * A call to this function will increment the running count of the endpoint.
1345 * In case it is not already running, the URBs for this endpoint will be
1346 * submitted. Otherwise, this function does nothing.
1347 *
1348 * Must be balanced to calls of snd_usb_endpoint_stop().
1349 *
1350 * Returns an error if the URB submission failed, 0 in all other cases.
1351 */
1352int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
1353{
1354 int err;
1355 unsigned int i;
1356
1357 if (atomic_read(&ep->chip->shutdown))
1358 return -EBADFD;
1359
1360 if (ep->sync_source)
1361 WRITE_ONCE(ep->sync_source->sync_sink, ep);
1362
1363 usb_audio_dbg(ep->chip, "Starting %s EP 0x%x (running %d)\n",
1364 ep_type_name(ep->type), ep->ep_num,
1365 atomic_read(&ep->running));
1366
1367 /* already running? */
1368 if (atomic_inc_return(&ep->running) != 1)
1369 return 0;
1370
1371 ep->active_mask = 0;
1372 ep->unlink_mask = 0;
1373 ep->phase = 0;
1374 ep->sample_accum = 0;
1375
1376 snd_usb_endpoint_start_quirk(ep);
1377
1378 /*
1379 * If this endpoint has a data endpoint as implicit feedback source,
1380 * don't start the urbs here. Instead, mark them all as available,
1381 * wait for the record urbs to return and queue the playback urbs
1382 * from that context.
1383 */
1384
1385 if (!ep_state_update(ep, EP_STATE_STOPPED, EP_STATE_RUNNING))
1386 goto __error;
1387
1388 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1389 !ep->chip->playback_first) {
1390 for (i = 0; i < ep->nurbs; i++) {
1391 struct snd_urb_ctx *ctx = ep->urb + i;
1392 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
1393 }
1394
1395 usb_audio_dbg(ep->chip, "No URB submission due to implicit fb sync\n");
1396 return 0;
1397 }
1398
1399 for (i = 0; i < ep->nurbs; i++) {
1400 struct urb *urb = ep->urb[i].urb;
1401
1402 if (snd_BUG_ON(!urb))
1403 goto __error;
1404
1405 if (usb_pipeout(ep->pipe)) {
1406 prepare_outbound_urb(ep, urb->context);
1407 } else {
1408 prepare_inbound_urb(ep, urb->context);
1409 }
1410
1411 err = usb_submit_urb(urb, GFP_ATOMIC);
1412 if (err < 0) {
1413 usb_audio_err(ep->chip,
1414 "cannot submit urb %d, error %d: %s\n",
1415 i, err, usb_error_string(err));
1416 goto __error;
1417 }
1418 set_bit(i, &ep->active_mask);
1419 }
1420
1421 usb_audio_dbg(ep->chip, "%d URBs submitted for EP 0x%x\n",
1422 ep->nurbs, ep->ep_num);
1423 return 0;
1424
1425__error:
1426 snd_usb_endpoint_stop(ep);
1427 return -EPIPE;
1428}
1429
1430/**
1431 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
1432 *
1433 * @ep: the endpoint to stop (may be NULL)
1434 *
1435 * A call to this function will decrement the running count of the endpoint.
1436 * In case the last user has requested the endpoint stop, the URBs will
1437 * actually be deactivated.
1438 *
1439 * Must be balanced to calls of snd_usb_endpoint_start().
1440 *
1441 * The caller needs to synchronize the pending stop operation via
1442 * snd_usb_endpoint_sync_pending_stop().
1443 */
1444void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep)
1445{
1446 if (!ep)
1447 return;
1448
1449 usb_audio_dbg(ep->chip, "Stopping %s EP 0x%x (running %d)\n",
1450 ep_type_name(ep->type), ep->ep_num,
1451 atomic_read(&ep->running));
1452
1453 if (snd_BUG_ON(!atomic_read(&ep->running)))
1454 return;
1455
1456 if (!atomic_dec_return(&ep->running)) {
1457 if (ep->sync_source)
1458 WRITE_ONCE(ep->sync_source->sync_sink, NULL);
1459 stop_urbs(ep, false);
1460 }
1461}
1462
1463/**
1464 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1465 *
1466 * @ep: the endpoint to release
1467 *
1468 * This function does not care for the endpoint's running count but will tear
1469 * down all the streaming URBs immediately.
1470 */
1471void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1472{
1473 release_urbs(ep, true);
1474}
1475
1476/**
1477 * snd_usb_endpoint_free_all: Free the resources of an snd_usb_endpoint
1478 * @chip: The chip
1479 *
1480 * This free all endpoints and those resources
1481 */
1482void snd_usb_endpoint_free_all(struct snd_usb_audio *chip)
1483{
1484 struct snd_usb_endpoint *ep, *en;
1485 struct snd_usb_iface_ref *ip, *in;
1486
1487 list_for_each_entry_safe(ep, en, &chip->ep_list, list)
1488 kfree(ep);
1489
1490 list_for_each_entry_safe(ip, in, &chip->iface_ref_list, list)
1491 kfree(ip);
1492}
1493
1494/*
1495 * snd_usb_handle_sync_urb: parse an USB sync packet
1496 *
1497 * @ep: the endpoint to handle the packet
1498 * @sender: the sending endpoint
1499 * @urb: the received packet
1500 *
1501 * This function is called from the context of an endpoint that received
1502 * the packet and is used to let another endpoint object handle the payload.
1503 */
1504static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1505 struct snd_usb_endpoint *sender,
1506 const struct urb *urb)
1507{
1508 int shift;
1509 unsigned int f;
1510 unsigned long flags;
1511
1512 snd_BUG_ON(ep == sender);
1513
1514 /*
1515 * In case the endpoint is operating in implicit feedback mode, prepare
1516 * a new outbound URB that has the same layout as the received packet
1517 * and add it to the list of pending urbs. queue_pending_output_urbs()
1518 * will take care of them later.
1519 */
1520 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1521 atomic_read(&ep->running)) {
1522
1523 /* implicit feedback case */
1524 int i, bytes = 0;
1525 struct snd_urb_ctx *in_ctx;
1526 struct snd_usb_packet_info *out_packet;
1527
1528 in_ctx = urb->context;
1529
1530 /* Count overall packet size */
1531 for (i = 0; i < in_ctx->packets; i++)
1532 if (urb->iso_frame_desc[i].status == 0)
1533 bytes += urb->iso_frame_desc[i].actual_length;
1534
1535 /*
1536 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1537 * streaming once it received a 0-byte OUT URB
1538 */
1539 if (bytes == 0)
1540 return;
1541
1542 spin_lock_irqsave(&ep->lock, flags);
1543 if (ep->next_packet_queued >= ARRAY_SIZE(ep->next_packet)) {
1544 spin_unlock_irqrestore(&ep->lock, flags);
1545 usb_audio_err(ep->chip,
1546 "next package FIFO overflow EP 0x%x\n",
1547 ep->ep_num);
1548 notify_xrun(ep);
1549 return;
1550 }
1551
1552 out_packet = next_packet_fifo_enqueue(ep);
1553
1554 /*
1555 * Iterate through the inbound packet and prepare the lengths
1556 * for the output packet. The OUT packet we are about to send
1557 * will have the same amount of payload bytes per stride as the
1558 * IN packet we just received. Since the actual size is scaled
1559 * by the stride, use the sender stride to calculate the length
1560 * in case the number of channels differ between the implicitly
1561 * fed-back endpoint and the synchronizing endpoint.
1562 */
1563
1564 out_packet->packets = in_ctx->packets;
1565 for (i = 0; i < in_ctx->packets; i++) {
1566 if (urb->iso_frame_desc[i].status == 0)
1567 out_packet->packet_size[i] =
1568 urb->iso_frame_desc[i].actual_length / sender->stride;
1569 else
1570 out_packet->packet_size[i] = 0;
1571 }
1572
1573 spin_unlock_irqrestore(&ep->lock, flags);
1574 queue_pending_output_urbs(ep);
1575
1576 return;
1577 }
1578
1579 /*
1580 * process after playback sync complete
1581 *
1582 * Full speed devices report feedback values in 10.14 format as samples
1583 * per frame, high speed devices in 16.16 format as samples per
1584 * microframe.
1585 *
1586 * Because the Audio Class 1 spec was written before USB 2.0, many high
1587 * speed devices use a wrong interpretation, some others use an
1588 * entirely different format.
1589 *
1590 * Therefore, we cannot predict what format any particular device uses
1591 * and must detect it automatically.
1592 */
1593
1594 if (urb->iso_frame_desc[0].status != 0 ||
1595 urb->iso_frame_desc[0].actual_length < 3)
1596 return;
1597
1598 f = le32_to_cpup(urb->transfer_buffer);
1599 if (urb->iso_frame_desc[0].actual_length == 3)
1600 f &= 0x00ffffff;
1601 else
1602 f &= 0x0fffffff;
1603
1604 if (f == 0)
1605 return;
1606
1607 if (unlikely(sender->tenor_fb_quirk)) {
1608 /*
1609 * Devices based on Tenor 8802 chipsets (TEAC UD-H01
1610 * and others) sometimes change the feedback value
1611 * by +/- 0x1.0000.
1612 */
1613 if (f < ep->freqn - 0x8000)
1614 f += 0xf000;
1615 else if (f > ep->freqn + 0x8000)
1616 f -= 0xf000;
1617 } else if (unlikely(ep->freqshift == INT_MIN)) {
1618 /*
1619 * The first time we see a feedback value, determine its format
1620 * by shifting it left or right until it matches the nominal
1621 * frequency value. This assumes that the feedback does not
1622 * differ from the nominal value more than +50% or -25%.
1623 */
1624 shift = 0;
1625 while (f < ep->freqn - ep->freqn / 4) {
1626 f <<= 1;
1627 shift++;
1628 }
1629 while (f > ep->freqn + ep->freqn / 2) {
1630 f >>= 1;
1631 shift--;
1632 }
1633 ep->freqshift = shift;
1634 } else if (ep->freqshift >= 0)
1635 f <<= ep->freqshift;
1636 else
1637 f >>= -ep->freqshift;
1638
1639 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1640 /*
1641 * If the frequency looks valid, set it.
1642 * This value is referred to in prepare_playback_urb().
1643 */
1644 spin_lock_irqsave(&ep->lock, flags);
1645 ep->freqm = f;
1646 spin_unlock_irqrestore(&ep->lock, flags);
1647 } else {
1648 /*
1649 * Out of range; maybe the shift value is wrong.
1650 * Reset it so that we autodetect again the next time.
1651 */
1652 ep->freqshift = INT_MIN;
1653 }
1654}
1655
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 "clock.h"
22#include "quirks.h"
23
24enum {
25 EP_STATE_STOPPED,
26 EP_STATE_RUNNING,
27 EP_STATE_STOPPING,
28};
29
30/* interface refcounting */
31struct snd_usb_iface_ref {
32 unsigned char iface;
33 bool need_setup;
34 int opened;
35 int altset;
36 struct list_head list;
37};
38
39/* clock refcounting */
40struct snd_usb_clock_ref {
41 unsigned char clock;
42 atomic_t locked;
43 int opened;
44 int rate;
45 bool need_setup;
46 struct list_head list;
47};
48
49/*
50 * snd_usb_endpoint is a model that abstracts everything related to an
51 * USB endpoint and its streaming.
52 *
53 * There are functions to activate and deactivate the streaming URBs and
54 * optional callbacks to let the pcm logic handle the actual content of the
55 * packets for playback and record. Thus, the bus streaming and the audio
56 * handlers are fully decoupled.
57 *
58 * There are two different types of endpoints in audio applications.
59 *
60 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
61 * inbound and outbound traffic.
62 *
63 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
64 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
65 * (3 or 4 bytes).
66 *
67 * Each endpoint has to be configured prior to being used by calling
68 * snd_usb_endpoint_set_params().
69 *
70 * The model incorporates a reference counting, so that multiple users
71 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
72 * only the first user will effectively start the URBs, and only the last
73 * one to stop it will tear the URBs down again.
74 */
75
76/*
77 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
78 * this will overflow at approx 524 kHz
79 */
80static inline unsigned get_usb_full_speed_rate(unsigned int rate)
81{
82 return ((rate << 13) + 62) / 125;
83}
84
85/*
86 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
87 * this will overflow at approx 4 MHz
88 */
89static inline unsigned get_usb_high_speed_rate(unsigned int rate)
90{
91 return ((rate << 10) + 62) / 125;
92}
93
94/*
95 * release a urb data
96 */
97static void release_urb_ctx(struct snd_urb_ctx *u)
98{
99 if (u->urb && u->buffer_size)
100 usb_free_coherent(u->ep->chip->dev, u->buffer_size,
101 u->urb->transfer_buffer,
102 u->urb->transfer_dma);
103 usb_free_urb(u->urb);
104 u->urb = NULL;
105 u->buffer_size = 0;
106}
107
108static const char *usb_error_string(int err)
109{
110 switch (err) {
111 case -ENODEV:
112 return "no device";
113 case -ENOENT:
114 return "endpoint not enabled";
115 case -EPIPE:
116 return "endpoint stalled";
117 case -ENOSPC:
118 return "not enough bandwidth";
119 case -ESHUTDOWN:
120 return "device disabled";
121 case -EHOSTUNREACH:
122 return "device suspended";
123 case -EINVAL:
124 case -EAGAIN:
125 case -EFBIG:
126 case -EMSGSIZE:
127 return "internal error";
128 default:
129 return "unknown error";
130 }
131}
132
133static inline bool ep_state_running(struct snd_usb_endpoint *ep)
134{
135 return atomic_read(&ep->state) == EP_STATE_RUNNING;
136}
137
138static inline bool ep_state_update(struct snd_usb_endpoint *ep, int old, int new)
139{
140 return atomic_try_cmpxchg(&ep->state, &old, new);
141}
142
143/**
144 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
145 *
146 * @ep: The snd_usb_endpoint
147 *
148 * Determine whether an endpoint is driven by an implicit feedback
149 * data endpoint source.
150 */
151int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
152{
153 return ep->implicit_fb_sync && usb_pipeout(ep->pipe);
154}
155
156/*
157 * Return the number of samples to be sent in the next packet
158 * for streaming based on information derived from sync endpoints
159 *
160 * This won't be used for implicit feedback which takes the packet size
161 * returned from the sync source
162 */
163static int slave_next_packet_size(struct snd_usb_endpoint *ep,
164 unsigned int avail)
165{
166 unsigned long flags;
167 unsigned int phase;
168 int ret;
169
170 if (ep->fill_max)
171 return ep->maxframesize;
172
173 spin_lock_irqsave(&ep->lock, flags);
174 phase = (ep->phase & 0xffff) + (ep->freqm << ep->datainterval);
175 ret = min(phase >> 16, ep->maxframesize);
176 if (avail && ret >= avail)
177 ret = -EAGAIN;
178 else
179 ep->phase = phase;
180 spin_unlock_irqrestore(&ep->lock, flags);
181
182 return ret;
183}
184
185/*
186 * Return the number of samples to be sent in the next packet
187 * for adaptive and synchronous endpoints
188 */
189static int next_packet_size(struct snd_usb_endpoint *ep, unsigned int avail)
190{
191 unsigned int sample_accum;
192 int ret;
193
194 if (ep->fill_max)
195 return ep->maxframesize;
196
197 sample_accum = ep->sample_accum + ep->sample_rem;
198 if (sample_accum >= ep->pps) {
199 sample_accum -= ep->pps;
200 ret = ep->packsize[1];
201 } else {
202 ret = ep->packsize[0];
203 }
204 if (avail && ret >= avail)
205 ret = -EAGAIN;
206 else
207 ep->sample_accum = sample_accum;
208
209 return ret;
210}
211
212/*
213 * snd_usb_endpoint_next_packet_size: Return the number of samples to be sent
214 * in the next packet
215 *
216 * If the size is equal or exceeds @avail, don't proceed but return -EAGAIN
217 * Exception: @avail = 0 for skipping the check.
218 */
219int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep,
220 struct snd_urb_ctx *ctx, int idx,
221 unsigned int avail)
222{
223 unsigned int packet;
224
225 packet = ctx->packet_size[idx];
226 if (packet) {
227 if (avail && packet >= avail)
228 return -EAGAIN;
229 return packet;
230 }
231
232 if (ep->sync_source)
233 return slave_next_packet_size(ep, avail);
234 else
235 return next_packet_size(ep, avail);
236}
237
238static void call_retire_callback(struct snd_usb_endpoint *ep,
239 struct urb *urb)
240{
241 struct snd_usb_substream *data_subs;
242
243 data_subs = READ_ONCE(ep->data_subs);
244 if (data_subs && ep->retire_data_urb)
245 ep->retire_data_urb(data_subs, urb);
246}
247
248static void retire_outbound_urb(struct snd_usb_endpoint *ep,
249 struct snd_urb_ctx *urb_ctx)
250{
251 call_retire_callback(ep, urb_ctx->urb);
252}
253
254static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
255 struct snd_usb_endpoint *sender,
256 const struct urb *urb);
257
258static void retire_inbound_urb(struct snd_usb_endpoint *ep,
259 struct snd_urb_ctx *urb_ctx)
260{
261 struct urb *urb = urb_ctx->urb;
262 struct snd_usb_endpoint *sync_sink;
263
264 if (unlikely(ep->skip_packets > 0)) {
265 ep->skip_packets--;
266 return;
267 }
268
269 sync_sink = READ_ONCE(ep->sync_sink);
270 if (sync_sink)
271 snd_usb_handle_sync_urb(sync_sink, ep, urb);
272
273 call_retire_callback(ep, urb);
274}
275
276static inline bool has_tx_length_quirk(struct snd_usb_audio *chip)
277{
278 return chip->quirk_flags & QUIRK_FLAG_TX_LENGTH;
279}
280
281static void prepare_silent_urb(struct snd_usb_endpoint *ep,
282 struct snd_urb_ctx *ctx)
283{
284 struct urb *urb = ctx->urb;
285 unsigned int offs = 0;
286 unsigned int extra = 0;
287 __le32 packet_length;
288 int i;
289
290 /* For tx_length_quirk, put packet length at start of packet */
291 if (has_tx_length_quirk(ep->chip))
292 extra = sizeof(packet_length);
293
294 for (i = 0; i < ctx->packets; ++i) {
295 unsigned int offset;
296 unsigned int length;
297 int counts;
298
299 counts = snd_usb_endpoint_next_packet_size(ep, ctx, i, 0);
300 length = counts * ep->stride; /* number of silent bytes */
301 offset = offs * ep->stride + extra * i;
302 urb->iso_frame_desc[i].offset = offset;
303 urb->iso_frame_desc[i].length = length + extra;
304 if (extra) {
305 packet_length = cpu_to_le32(length);
306 memcpy(urb->transfer_buffer + offset,
307 &packet_length, sizeof(packet_length));
308 }
309 memset(urb->transfer_buffer + offset + extra,
310 ep->silence_value, length);
311 offs += counts;
312 }
313
314 urb->number_of_packets = ctx->packets;
315 urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
316 ctx->queued = 0;
317}
318
319/*
320 * Prepare a PLAYBACK urb for submission to the bus.
321 */
322static int prepare_outbound_urb(struct snd_usb_endpoint *ep,
323 struct snd_urb_ctx *ctx,
324 bool in_stream_lock)
325{
326 struct urb *urb = ctx->urb;
327 unsigned char *cp = urb->transfer_buffer;
328 struct snd_usb_substream *data_subs;
329
330 urb->dev = ep->chip->dev; /* we need to set this at each time */
331
332 switch (ep->type) {
333 case SND_USB_ENDPOINT_TYPE_DATA:
334 data_subs = READ_ONCE(ep->data_subs);
335 if (data_subs && ep->prepare_data_urb)
336 return ep->prepare_data_urb(data_subs, urb, in_stream_lock);
337 /* no data provider, so send silence */
338 prepare_silent_urb(ep, ctx);
339 break;
340
341 case SND_USB_ENDPOINT_TYPE_SYNC:
342 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
343 /*
344 * fill the length and offset of each urb descriptor.
345 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
346 */
347 urb->iso_frame_desc[0].length = 4;
348 urb->iso_frame_desc[0].offset = 0;
349 cp[0] = ep->freqn;
350 cp[1] = ep->freqn >> 8;
351 cp[2] = ep->freqn >> 16;
352 cp[3] = ep->freqn >> 24;
353 } else {
354 /*
355 * fill the length and offset of each urb descriptor.
356 * the fixed 10.14 frequency is passed through the pipe.
357 */
358 urb->iso_frame_desc[0].length = 3;
359 urb->iso_frame_desc[0].offset = 0;
360 cp[0] = ep->freqn >> 2;
361 cp[1] = ep->freqn >> 10;
362 cp[2] = ep->freqn >> 18;
363 }
364
365 break;
366 }
367 return 0;
368}
369
370/*
371 * Prepare a CAPTURE or SYNC urb for submission to the bus.
372 */
373static int prepare_inbound_urb(struct snd_usb_endpoint *ep,
374 struct snd_urb_ctx *urb_ctx)
375{
376 int i, offs;
377 struct urb *urb = urb_ctx->urb;
378
379 urb->dev = ep->chip->dev; /* we need to set this at each time */
380
381 switch (ep->type) {
382 case SND_USB_ENDPOINT_TYPE_DATA:
383 offs = 0;
384 for (i = 0; i < urb_ctx->packets; i++) {
385 urb->iso_frame_desc[i].offset = offs;
386 urb->iso_frame_desc[i].length = ep->curpacksize;
387 offs += ep->curpacksize;
388 }
389
390 urb->transfer_buffer_length = offs;
391 urb->number_of_packets = urb_ctx->packets;
392 break;
393
394 case SND_USB_ENDPOINT_TYPE_SYNC:
395 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
396 urb->iso_frame_desc[0].offset = 0;
397 break;
398 }
399 return 0;
400}
401
402/* notify an error as XRUN to the assigned PCM data substream */
403static void notify_xrun(struct snd_usb_endpoint *ep)
404{
405 struct snd_usb_substream *data_subs;
406
407 data_subs = READ_ONCE(ep->data_subs);
408 if (data_subs && data_subs->pcm_substream)
409 snd_pcm_stop_xrun(data_subs->pcm_substream);
410}
411
412static struct snd_usb_packet_info *
413next_packet_fifo_enqueue(struct snd_usb_endpoint *ep)
414{
415 struct snd_usb_packet_info *p;
416
417 p = ep->next_packet + (ep->next_packet_head + ep->next_packet_queued) %
418 ARRAY_SIZE(ep->next_packet);
419 ep->next_packet_queued++;
420 return p;
421}
422
423static struct snd_usb_packet_info *
424next_packet_fifo_dequeue(struct snd_usb_endpoint *ep)
425{
426 struct snd_usb_packet_info *p;
427
428 p = ep->next_packet + ep->next_packet_head;
429 ep->next_packet_head++;
430 ep->next_packet_head %= ARRAY_SIZE(ep->next_packet);
431 ep->next_packet_queued--;
432 return p;
433}
434
435static void push_back_to_ready_list(struct snd_usb_endpoint *ep,
436 struct snd_urb_ctx *ctx)
437{
438 unsigned long flags;
439
440 spin_lock_irqsave(&ep->lock, flags);
441 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
442 spin_unlock_irqrestore(&ep->lock, flags);
443}
444
445/*
446 * Send output urbs that have been prepared previously. URBs are dequeued
447 * from ep->ready_playback_urbs and in case there aren't any available
448 * or there are no packets that have been prepared, this function does
449 * nothing.
450 *
451 * The reason why the functionality of sending and preparing URBs is separated
452 * is that host controllers don't guarantee the order in which they return
453 * inbound and outbound packets to their submitters.
454 *
455 * This function is used both for implicit feedback endpoints and in low-
456 * latency playback mode.
457 */
458void snd_usb_queue_pending_output_urbs(struct snd_usb_endpoint *ep,
459 bool in_stream_lock)
460{
461 bool implicit_fb = snd_usb_endpoint_implicit_feedback_sink(ep);
462
463 while (ep_state_running(ep)) {
464
465 unsigned long flags;
466 struct snd_usb_packet_info *packet;
467 struct snd_urb_ctx *ctx = NULL;
468 int err, i;
469
470 spin_lock_irqsave(&ep->lock, flags);
471 if ((!implicit_fb || ep->next_packet_queued > 0) &&
472 !list_empty(&ep->ready_playback_urbs)) {
473 /* take URB out of FIFO */
474 ctx = list_first_entry(&ep->ready_playback_urbs,
475 struct snd_urb_ctx, ready_list);
476 list_del_init(&ctx->ready_list);
477 if (implicit_fb)
478 packet = next_packet_fifo_dequeue(ep);
479 }
480 spin_unlock_irqrestore(&ep->lock, flags);
481
482 if (ctx == NULL)
483 return;
484
485 /* copy over the length information */
486 if (implicit_fb) {
487 for (i = 0; i < packet->packets; i++)
488 ctx->packet_size[i] = packet->packet_size[i];
489 }
490
491 /* call the data handler to fill in playback data */
492 err = prepare_outbound_urb(ep, ctx, in_stream_lock);
493 /* can be stopped during prepare callback */
494 if (unlikely(!ep_state_running(ep)))
495 break;
496 if (err < 0) {
497 /* push back to ready list again for -EAGAIN */
498 if (err == -EAGAIN)
499 push_back_to_ready_list(ep, ctx);
500 else
501 notify_xrun(ep);
502 return;
503 }
504
505 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
506 if (err < 0) {
507 usb_audio_err(ep->chip,
508 "Unable to submit urb #%d: %d at %s\n",
509 ctx->index, err, __func__);
510 notify_xrun(ep);
511 return;
512 }
513
514 set_bit(ctx->index, &ep->active_mask);
515 atomic_inc(&ep->submitted_urbs);
516 }
517}
518
519/*
520 * complete callback for urbs
521 */
522static void snd_complete_urb(struct urb *urb)
523{
524 struct snd_urb_ctx *ctx = urb->context;
525 struct snd_usb_endpoint *ep = ctx->ep;
526 int err;
527
528 if (unlikely(urb->status == -ENOENT || /* unlinked */
529 urb->status == -ENODEV || /* device removed */
530 urb->status == -ECONNRESET || /* unlinked */
531 urb->status == -ESHUTDOWN)) /* device disabled */
532 goto exit_clear;
533 /* device disconnected */
534 if (unlikely(atomic_read(&ep->chip->shutdown)))
535 goto exit_clear;
536
537 if (unlikely(!ep_state_running(ep)))
538 goto exit_clear;
539
540 if (usb_pipeout(ep->pipe)) {
541 retire_outbound_urb(ep, ctx);
542 /* can be stopped during retire callback */
543 if (unlikely(!ep_state_running(ep)))
544 goto exit_clear;
545
546 /* in low-latency and implicit-feedback modes, push back the
547 * URB to ready list at first, then process as much as possible
548 */
549 if (ep->lowlatency_playback ||
550 snd_usb_endpoint_implicit_feedback_sink(ep)) {
551 push_back_to_ready_list(ep, ctx);
552 clear_bit(ctx->index, &ep->active_mask);
553 snd_usb_queue_pending_output_urbs(ep, false);
554 atomic_dec(&ep->submitted_urbs); /* decrement at last */
555 return;
556 }
557
558 /* in non-lowlatency mode, no error handling for prepare */
559 prepare_outbound_urb(ep, ctx, false);
560 /* can be stopped during prepare callback */
561 if (unlikely(!ep_state_running(ep)))
562 goto exit_clear;
563 } else {
564 retire_inbound_urb(ep, ctx);
565 /* can be stopped during retire callback */
566 if (unlikely(!ep_state_running(ep)))
567 goto exit_clear;
568
569 prepare_inbound_urb(ep, ctx);
570 }
571
572 err = usb_submit_urb(urb, GFP_ATOMIC);
573 if (err == 0)
574 return;
575
576 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
577 notify_xrun(ep);
578
579exit_clear:
580 clear_bit(ctx->index, &ep->active_mask);
581 atomic_dec(&ep->submitted_urbs);
582}
583
584/*
585 * Find or create a refcount object for the given interface
586 *
587 * The objects are released altogether in snd_usb_endpoint_free_all()
588 */
589static struct snd_usb_iface_ref *
590iface_ref_find(struct snd_usb_audio *chip, int iface)
591{
592 struct snd_usb_iface_ref *ip;
593
594 list_for_each_entry(ip, &chip->iface_ref_list, list)
595 if (ip->iface == iface)
596 return ip;
597
598 ip = kzalloc(sizeof(*ip), GFP_KERNEL);
599 if (!ip)
600 return NULL;
601 ip->iface = iface;
602 list_add_tail(&ip->list, &chip->iface_ref_list);
603 return ip;
604}
605
606/* Similarly, a refcount object for clock */
607static struct snd_usb_clock_ref *
608clock_ref_find(struct snd_usb_audio *chip, int clock)
609{
610 struct snd_usb_clock_ref *ref;
611
612 list_for_each_entry(ref, &chip->clock_ref_list, list)
613 if (ref->clock == clock)
614 return ref;
615
616 ref = kzalloc(sizeof(*ref), GFP_KERNEL);
617 if (!ref)
618 return NULL;
619 ref->clock = clock;
620 atomic_set(&ref->locked, 0);
621 list_add_tail(&ref->list, &chip->clock_ref_list);
622 return ref;
623}
624
625/*
626 * Get the existing endpoint object corresponding EP
627 * Returns NULL if not present.
628 */
629struct snd_usb_endpoint *
630snd_usb_get_endpoint(struct snd_usb_audio *chip, int ep_num)
631{
632 struct snd_usb_endpoint *ep;
633
634 list_for_each_entry(ep, &chip->ep_list, list) {
635 if (ep->ep_num == ep_num)
636 return ep;
637 }
638
639 return NULL;
640}
641
642#define ep_type_name(type) \
643 (type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync")
644
645/**
646 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
647 *
648 * @chip: The chip
649 * @ep_num: The number of the endpoint to use
650 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
651 *
652 * If the requested endpoint has not been added to the given chip before,
653 * a new instance is created.
654 *
655 * Returns zero on success or a negative error code.
656 *
657 * New endpoints will be added to chip->ep_list and freed by
658 * calling snd_usb_endpoint_free_all().
659 *
660 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
661 * bNumEndpoints > 1 beforehand.
662 */
663int snd_usb_add_endpoint(struct snd_usb_audio *chip, int ep_num, int type)
664{
665 struct snd_usb_endpoint *ep;
666 bool is_playback;
667
668 ep = snd_usb_get_endpoint(chip, ep_num);
669 if (ep)
670 return 0;
671
672 usb_audio_dbg(chip, "Creating new %s endpoint #%x\n",
673 ep_type_name(type),
674 ep_num);
675 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
676 if (!ep)
677 return -ENOMEM;
678
679 ep->chip = chip;
680 spin_lock_init(&ep->lock);
681 ep->type = type;
682 ep->ep_num = ep_num;
683 INIT_LIST_HEAD(&ep->ready_playback_urbs);
684 atomic_set(&ep->submitted_urbs, 0);
685
686 is_playback = ((ep_num & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT);
687 ep_num &= USB_ENDPOINT_NUMBER_MASK;
688 if (is_playback)
689 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
690 else
691 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
692
693 list_add_tail(&ep->list, &chip->ep_list);
694 return 0;
695}
696
697/* Set up syncinterval and maxsyncsize for a sync EP */
698static void endpoint_set_syncinterval(struct snd_usb_audio *chip,
699 struct snd_usb_endpoint *ep)
700{
701 struct usb_host_interface *alts;
702 struct usb_endpoint_descriptor *desc;
703
704 alts = snd_usb_get_host_interface(chip, ep->iface, ep->altsetting);
705 if (!alts)
706 return;
707
708 desc = get_endpoint(alts, ep->ep_idx);
709 if (desc->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
710 desc->bRefresh >= 1 && desc->bRefresh <= 9)
711 ep->syncinterval = desc->bRefresh;
712 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
713 ep->syncinterval = 1;
714 else if (desc->bInterval >= 1 && desc->bInterval <= 16)
715 ep->syncinterval = desc->bInterval - 1;
716 else
717 ep->syncinterval = 3;
718
719 ep->syncmaxsize = le16_to_cpu(desc->wMaxPacketSize);
720}
721
722static bool endpoint_compatible(struct snd_usb_endpoint *ep,
723 const struct audioformat *fp,
724 const struct snd_pcm_hw_params *params)
725{
726 if (!ep->opened)
727 return false;
728 if (ep->cur_audiofmt != fp)
729 return false;
730 if (ep->cur_rate != params_rate(params) ||
731 ep->cur_format != params_format(params) ||
732 ep->cur_period_frames != params_period_size(params) ||
733 ep->cur_buffer_periods != params_periods(params))
734 return false;
735 return true;
736}
737
738/*
739 * Check whether the given fp and hw params are compatible with the current
740 * setup of the target EP for implicit feedback sync
741 */
742bool snd_usb_endpoint_compatible(struct snd_usb_audio *chip,
743 struct snd_usb_endpoint *ep,
744 const struct audioformat *fp,
745 const struct snd_pcm_hw_params *params)
746{
747 bool ret;
748
749 mutex_lock(&chip->mutex);
750 ret = endpoint_compatible(ep, fp, params);
751 mutex_unlock(&chip->mutex);
752 return ret;
753}
754
755/*
756 * snd_usb_endpoint_open: Open the endpoint
757 *
758 * Called from hw_params to assign the endpoint to the substream.
759 * It's reference-counted, and only the first opener is allowed to set up
760 * arbitrary parameters. The later opener must be compatible with the
761 * former opened parameters.
762 * The endpoint needs to be closed via snd_usb_endpoint_close() later.
763 *
764 * Note that this function doesn't configure the endpoint. The substream
765 * needs to set it up later via snd_usb_endpoint_set_params() and
766 * snd_usb_endpoint_prepare().
767 */
768struct snd_usb_endpoint *
769snd_usb_endpoint_open(struct snd_usb_audio *chip,
770 const struct audioformat *fp,
771 const struct snd_pcm_hw_params *params,
772 bool is_sync_ep,
773 bool fixed_rate)
774{
775 struct snd_usb_endpoint *ep;
776 int ep_num = is_sync_ep ? fp->sync_ep : fp->endpoint;
777
778 mutex_lock(&chip->mutex);
779 ep = snd_usb_get_endpoint(chip, ep_num);
780 if (!ep) {
781 usb_audio_err(chip, "Cannot find EP 0x%x to open\n", ep_num);
782 goto unlock;
783 }
784
785 if (!ep->opened) {
786 if (is_sync_ep) {
787 ep->iface = fp->sync_iface;
788 ep->altsetting = fp->sync_altsetting;
789 ep->ep_idx = fp->sync_ep_idx;
790 } else {
791 ep->iface = fp->iface;
792 ep->altsetting = fp->altsetting;
793 ep->ep_idx = fp->ep_idx;
794 }
795 usb_audio_dbg(chip, "Open EP 0x%x, iface=%d:%d, idx=%d\n",
796 ep_num, ep->iface, ep->altsetting, ep->ep_idx);
797
798 ep->iface_ref = iface_ref_find(chip, ep->iface);
799 if (!ep->iface_ref) {
800 ep = NULL;
801 goto unlock;
802 }
803
804 if (fp->protocol != UAC_VERSION_1) {
805 ep->clock_ref = clock_ref_find(chip, fp->clock);
806 if (!ep->clock_ref) {
807 ep = NULL;
808 goto unlock;
809 }
810 ep->clock_ref->opened++;
811 }
812
813 ep->cur_audiofmt = fp;
814 ep->cur_channels = fp->channels;
815 ep->cur_rate = params_rate(params);
816 ep->cur_format = params_format(params);
817 ep->cur_frame_bytes = snd_pcm_format_physical_width(ep->cur_format) *
818 ep->cur_channels / 8;
819 ep->cur_period_frames = params_period_size(params);
820 ep->cur_period_bytes = ep->cur_period_frames * ep->cur_frame_bytes;
821 ep->cur_buffer_periods = params_periods(params);
822
823 if (ep->type == SND_USB_ENDPOINT_TYPE_SYNC)
824 endpoint_set_syncinterval(chip, ep);
825
826 ep->implicit_fb_sync = fp->implicit_fb;
827 ep->need_setup = true;
828 ep->need_prepare = true;
829 ep->fixed_rate = fixed_rate;
830
831 usb_audio_dbg(chip, " channels=%d, rate=%d, format=%s, period_bytes=%d, periods=%d, implicit_fb=%d\n",
832 ep->cur_channels, ep->cur_rate,
833 snd_pcm_format_name(ep->cur_format),
834 ep->cur_period_bytes, ep->cur_buffer_periods,
835 ep->implicit_fb_sync);
836
837 } else {
838 if (WARN_ON(!ep->iface_ref)) {
839 ep = NULL;
840 goto unlock;
841 }
842
843 if (!endpoint_compatible(ep, fp, params)) {
844 usb_audio_err(chip, "Incompatible EP setup for 0x%x\n",
845 ep_num);
846 ep = NULL;
847 goto unlock;
848 }
849
850 usb_audio_dbg(chip, "Reopened EP 0x%x (count %d)\n",
851 ep_num, ep->opened);
852 }
853
854 if (!ep->iface_ref->opened++)
855 ep->iface_ref->need_setup = true;
856
857 ep->opened++;
858
859 unlock:
860 mutex_unlock(&chip->mutex);
861 return ep;
862}
863
864/*
865 * snd_usb_endpoint_set_sync: Link data and sync endpoints
866 *
867 * Pass NULL to sync_ep to unlink again
868 */
869void snd_usb_endpoint_set_sync(struct snd_usb_audio *chip,
870 struct snd_usb_endpoint *data_ep,
871 struct snd_usb_endpoint *sync_ep)
872{
873 data_ep->sync_source = sync_ep;
874}
875
876/*
877 * Set data endpoint callbacks and the assigned data stream
878 *
879 * Called at PCM trigger and cleanups.
880 * Pass NULL to deactivate each callback.
881 */
882void snd_usb_endpoint_set_callback(struct snd_usb_endpoint *ep,
883 int (*prepare)(struct snd_usb_substream *subs,
884 struct urb *urb,
885 bool in_stream_lock),
886 void (*retire)(struct snd_usb_substream *subs,
887 struct urb *urb),
888 struct snd_usb_substream *data_subs)
889{
890 ep->prepare_data_urb = prepare;
891 ep->retire_data_urb = retire;
892 if (data_subs)
893 ep->lowlatency_playback = data_subs->lowlatency_playback;
894 else
895 ep->lowlatency_playback = false;
896 WRITE_ONCE(ep->data_subs, data_subs);
897}
898
899static int endpoint_set_interface(struct snd_usb_audio *chip,
900 struct snd_usb_endpoint *ep,
901 bool set)
902{
903 int altset = set ? ep->altsetting : 0;
904 int err;
905
906 if (ep->iface_ref->altset == altset)
907 return 0;
908
909 usb_audio_dbg(chip, "Setting usb interface %d:%d for EP 0x%x\n",
910 ep->iface, altset, ep->ep_num);
911 err = usb_set_interface(chip->dev, ep->iface, altset);
912 if (err < 0) {
913 usb_audio_err(chip, "%d:%d: usb_set_interface failed (%d)\n",
914 ep->iface, altset, err);
915 return err;
916 }
917
918 if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY)
919 msleep(50);
920 ep->iface_ref->altset = altset;
921 return 0;
922}
923
924/*
925 * snd_usb_endpoint_close: Close the endpoint
926 *
927 * Unreference the already opened endpoint via snd_usb_endpoint_open().
928 */
929void snd_usb_endpoint_close(struct snd_usb_audio *chip,
930 struct snd_usb_endpoint *ep)
931{
932 mutex_lock(&chip->mutex);
933 usb_audio_dbg(chip, "Closing EP 0x%x (count %d)\n",
934 ep->ep_num, ep->opened);
935
936 if (!--ep->iface_ref->opened &&
937 !(chip->quirk_flags & QUIRK_FLAG_IFACE_SKIP_CLOSE))
938 endpoint_set_interface(chip, ep, false);
939
940 if (!--ep->opened) {
941 if (ep->clock_ref) {
942 if (!--ep->clock_ref->opened)
943 ep->clock_ref->rate = 0;
944 }
945 ep->iface = 0;
946 ep->altsetting = 0;
947 ep->cur_audiofmt = NULL;
948 ep->cur_rate = 0;
949 ep->iface_ref = NULL;
950 ep->clock_ref = NULL;
951 usb_audio_dbg(chip, "EP 0x%x closed\n", ep->ep_num);
952 }
953 mutex_unlock(&chip->mutex);
954}
955
956/* Prepare for suspening EP, called from the main suspend handler */
957void snd_usb_endpoint_suspend(struct snd_usb_endpoint *ep)
958{
959 ep->need_prepare = true;
960 if (ep->iface_ref)
961 ep->iface_ref->need_setup = true;
962 if (ep->clock_ref)
963 ep->clock_ref->rate = 0;
964}
965
966/*
967 * wait until all urbs are processed.
968 */
969static int wait_clear_urbs(struct snd_usb_endpoint *ep)
970{
971 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
972 int alive;
973
974 if (atomic_read(&ep->state) != EP_STATE_STOPPING)
975 return 0;
976
977 do {
978 alive = atomic_read(&ep->submitted_urbs);
979 if (!alive)
980 break;
981
982 schedule_timeout_uninterruptible(1);
983 } while (time_before(jiffies, end_time));
984
985 if (alive)
986 usb_audio_err(ep->chip,
987 "timeout: still %d active urbs on EP #%x\n",
988 alive, ep->ep_num);
989
990 if (ep_state_update(ep, EP_STATE_STOPPING, EP_STATE_STOPPED)) {
991 ep->sync_sink = NULL;
992 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
993 }
994
995 return 0;
996}
997
998/* sync the pending stop operation;
999 * this function itself doesn't trigger the stop operation
1000 */
1001void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
1002{
1003 if (ep)
1004 wait_clear_urbs(ep);
1005}
1006
1007/*
1008 * Stop active urbs
1009 *
1010 * This function moves the EP to STOPPING state if it's being RUNNING.
1011 */
1012static int stop_urbs(struct snd_usb_endpoint *ep, bool force, bool keep_pending)
1013{
1014 unsigned int i;
1015 unsigned long flags;
1016
1017 if (!force && atomic_read(&ep->running))
1018 return -EBUSY;
1019
1020 if (!ep_state_update(ep, EP_STATE_RUNNING, EP_STATE_STOPPING))
1021 return 0;
1022
1023 spin_lock_irqsave(&ep->lock, flags);
1024 INIT_LIST_HEAD(&ep->ready_playback_urbs);
1025 ep->next_packet_head = 0;
1026 ep->next_packet_queued = 0;
1027 spin_unlock_irqrestore(&ep->lock, flags);
1028
1029 if (keep_pending)
1030 return 0;
1031
1032 for (i = 0; i < ep->nurbs; i++) {
1033 if (test_bit(i, &ep->active_mask)) {
1034 if (!test_and_set_bit(i, &ep->unlink_mask)) {
1035 struct urb *u = ep->urb[i].urb;
1036 usb_unlink_urb(u);
1037 }
1038 }
1039 }
1040
1041 return 0;
1042}
1043
1044/*
1045 * release an endpoint's urbs
1046 */
1047static int release_urbs(struct snd_usb_endpoint *ep, bool force)
1048{
1049 int i, err;
1050
1051 /* route incoming urbs to nirvana */
1052 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
1053
1054 /* stop and unlink urbs */
1055 err = stop_urbs(ep, force, false);
1056 if (err)
1057 return err;
1058
1059 wait_clear_urbs(ep);
1060
1061 for (i = 0; i < ep->nurbs; i++)
1062 release_urb_ctx(&ep->urb[i]);
1063
1064 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
1065 ep->syncbuf, ep->sync_dma);
1066
1067 ep->syncbuf = NULL;
1068 ep->nurbs = 0;
1069 return 0;
1070}
1071
1072/*
1073 * configure a data endpoint
1074 */
1075static int data_ep_set_params(struct snd_usb_endpoint *ep)
1076{
1077 struct snd_usb_audio *chip = ep->chip;
1078 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
1079 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
1080 unsigned int max_urbs, i;
1081 const struct audioformat *fmt = ep->cur_audiofmt;
1082 int frame_bits = ep->cur_frame_bytes * 8;
1083 int tx_length_quirk = (has_tx_length_quirk(chip) &&
1084 usb_pipeout(ep->pipe));
1085
1086 usb_audio_dbg(chip, "Setting params for data EP 0x%x, pipe 0x%x\n",
1087 ep->ep_num, ep->pipe);
1088
1089 if (ep->cur_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
1090 /*
1091 * When operating in DSD DOP mode, the size of a sample frame
1092 * in hardware differs from the actual physical format width
1093 * because we need to make room for the DOP markers.
1094 */
1095 frame_bits += ep->cur_channels << 3;
1096 }
1097
1098 ep->datainterval = fmt->datainterval;
1099 ep->stride = frame_bits >> 3;
1100
1101 switch (ep->cur_format) {
1102 case SNDRV_PCM_FORMAT_U8:
1103 ep->silence_value = 0x80;
1104 break;
1105 case SNDRV_PCM_FORMAT_DSD_U8:
1106 case SNDRV_PCM_FORMAT_DSD_U16_LE:
1107 case SNDRV_PCM_FORMAT_DSD_U32_LE:
1108 case SNDRV_PCM_FORMAT_DSD_U16_BE:
1109 case SNDRV_PCM_FORMAT_DSD_U32_BE:
1110 ep->silence_value = 0x69;
1111 break;
1112 default:
1113 ep->silence_value = 0;
1114 }
1115
1116 /* assume max. frequency is 50% higher than nominal */
1117 ep->freqmax = ep->freqn + (ep->freqn >> 1);
1118 /* Round up freqmax to nearest integer in order to calculate maximum
1119 * packet size, which must represent a whole number of frames.
1120 * This is accomplished by adding 0x0.ffff before converting the
1121 * Q16.16 format into integer.
1122 * In order to accurately calculate the maximum packet size when
1123 * the data interval is more than 1 (i.e. ep->datainterval > 0),
1124 * multiply by the data interval prior to rounding. For instance,
1125 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
1126 * frames with a data interval of 1, but 11 (10.25) frames with a
1127 * data interval of 2.
1128 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
1129 * maximum datainterval value of 3, at USB full speed, higher for
1130 * USB high speed, noting that ep->freqmax is in units of
1131 * frames per packet in Q16.16 format.)
1132 */
1133 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
1134 (frame_bits >> 3);
1135 if (tx_length_quirk)
1136 maxsize += sizeof(__le32); /* Space for length descriptor */
1137 /* but wMaxPacketSize might reduce this */
1138 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
1139 /* whatever fits into a max. size packet */
1140 unsigned int data_maxsize = maxsize = ep->maxpacksize;
1141
1142 if (tx_length_quirk)
1143 /* Need to remove the length descriptor to calc freq */
1144 data_maxsize -= sizeof(__le32);
1145 ep->freqmax = (data_maxsize / (frame_bits >> 3))
1146 << (16 - ep->datainterval);
1147 }
1148
1149 if (ep->fill_max)
1150 ep->curpacksize = ep->maxpacksize;
1151 else
1152 ep->curpacksize = maxsize;
1153
1154 if (snd_usb_get_speed(chip->dev) != USB_SPEED_FULL) {
1155 packs_per_ms = 8 >> ep->datainterval;
1156 max_packs_per_urb = MAX_PACKS_HS;
1157 } else {
1158 packs_per_ms = 1;
1159 max_packs_per_urb = MAX_PACKS;
1160 }
1161 if (ep->sync_source && !ep->implicit_fb_sync)
1162 max_packs_per_urb = min(max_packs_per_urb,
1163 1U << ep->sync_source->syncinterval);
1164 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
1165
1166 /*
1167 * Capture endpoints need to use small URBs because there's no way
1168 * to tell in advance where the next period will end, and we don't
1169 * want the next URB to complete much after the period ends.
1170 *
1171 * Playback endpoints with implicit sync much use the same parameters
1172 * as their corresponding capture endpoint.
1173 */
1174 if (usb_pipein(ep->pipe) || ep->implicit_fb_sync) {
1175
1176 urb_packs = packs_per_ms;
1177 /*
1178 * Wireless devices can poll at a max rate of once per 4ms.
1179 * For dataintervals less than 5, increase the packet count to
1180 * allow the host controller to use bursting to fill in the
1181 * gaps.
1182 */
1183 if (snd_usb_get_speed(chip->dev) == USB_SPEED_WIRELESS) {
1184 int interval = ep->datainterval;
1185 while (interval < 5) {
1186 urb_packs <<= 1;
1187 ++interval;
1188 }
1189 }
1190 /* make capture URBs <= 1 ms and smaller than a period */
1191 urb_packs = min(max_packs_per_urb, urb_packs);
1192 while (urb_packs > 1 && urb_packs * maxsize >= ep->cur_period_bytes)
1193 urb_packs >>= 1;
1194 ep->nurbs = MAX_URBS;
1195
1196 /*
1197 * Playback endpoints without implicit sync are adjusted so that
1198 * a period fits as evenly as possible in the smallest number of
1199 * URBs. The total number of URBs is adjusted to the size of the
1200 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
1201 */
1202 } else {
1203 /* determine how small a packet can be */
1204 minsize = (ep->freqn >> (16 - ep->datainterval)) *
1205 (frame_bits >> 3);
1206 /* with sync from device, assume it can be 12% lower */
1207 if (ep->sync_source)
1208 minsize -= minsize >> 3;
1209 minsize = max(minsize, 1u);
1210
1211 /* how many packets will contain an entire ALSA period? */
1212 max_packs_per_period = DIV_ROUND_UP(ep->cur_period_bytes, minsize);
1213
1214 /* how many URBs will contain a period? */
1215 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
1216 max_packs_per_urb);
1217 /* how many packets are needed in each URB? */
1218 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
1219
1220 /* limit the number of frames in a single URB */
1221 ep->max_urb_frames = DIV_ROUND_UP(ep->cur_period_frames,
1222 urbs_per_period);
1223
1224 /* try to use enough URBs to contain an entire ALSA buffer */
1225 max_urbs = min((unsigned) MAX_URBS,
1226 MAX_QUEUE * packs_per_ms / urb_packs);
1227 ep->nurbs = min(max_urbs, urbs_per_period * ep->cur_buffer_periods);
1228 }
1229
1230 /* allocate and initialize data urbs */
1231 for (i = 0; i < ep->nurbs; i++) {
1232 struct snd_urb_ctx *u = &ep->urb[i];
1233 u->index = i;
1234 u->ep = ep;
1235 u->packets = urb_packs;
1236 u->buffer_size = maxsize * u->packets;
1237
1238 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
1239 u->packets++; /* for transfer delimiter */
1240 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
1241 if (!u->urb)
1242 goto out_of_memory;
1243
1244 u->urb->transfer_buffer =
1245 usb_alloc_coherent(chip->dev, u->buffer_size,
1246 GFP_KERNEL, &u->urb->transfer_dma);
1247 if (!u->urb->transfer_buffer)
1248 goto out_of_memory;
1249 u->urb->pipe = ep->pipe;
1250 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1251 u->urb->interval = 1 << ep->datainterval;
1252 u->urb->context = u;
1253 u->urb->complete = snd_complete_urb;
1254 INIT_LIST_HEAD(&u->ready_list);
1255 }
1256
1257 return 0;
1258
1259out_of_memory:
1260 release_urbs(ep, false);
1261 return -ENOMEM;
1262}
1263
1264/*
1265 * configure a sync endpoint
1266 */
1267static int sync_ep_set_params(struct snd_usb_endpoint *ep)
1268{
1269 struct snd_usb_audio *chip = ep->chip;
1270 int i;
1271
1272 usb_audio_dbg(chip, "Setting params for sync EP 0x%x, pipe 0x%x\n",
1273 ep->ep_num, ep->pipe);
1274
1275 ep->syncbuf = usb_alloc_coherent(chip->dev, SYNC_URBS * 4,
1276 GFP_KERNEL, &ep->sync_dma);
1277 if (!ep->syncbuf)
1278 return -ENOMEM;
1279
1280 ep->nurbs = SYNC_URBS;
1281 for (i = 0; i < SYNC_URBS; i++) {
1282 struct snd_urb_ctx *u = &ep->urb[i];
1283 u->index = i;
1284 u->ep = ep;
1285 u->packets = 1;
1286 u->urb = usb_alloc_urb(1, GFP_KERNEL);
1287 if (!u->urb)
1288 goto out_of_memory;
1289 u->urb->transfer_buffer = ep->syncbuf + i * 4;
1290 u->urb->transfer_dma = ep->sync_dma + i * 4;
1291 u->urb->transfer_buffer_length = 4;
1292 u->urb->pipe = ep->pipe;
1293 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1294 u->urb->number_of_packets = 1;
1295 u->urb->interval = 1 << ep->syncinterval;
1296 u->urb->context = u;
1297 u->urb->complete = snd_complete_urb;
1298 }
1299
1300 return 0;
1301
1302out_of_memory:
1303 release_urbs(ep, false);
1304 return -ENOMEM;
1305}
1306
1307/* update the rate of the referred clock; return the actual rate */
1308static int update_clock_ref_rate(struct snd_usb_audio *chip,
1309 struct snd_usb_endpoint *ep)
1310{
1311 struct snd_usb_clock_ref *clock = ep->clock_ref;
1312 int rate = ep->cur_rate;
1313
1314 if (!clock || clock->rate == rate)
1315 return rate;
1316 if (clock->rate) {
1317 if (atomic_read(&clock->locked))
1318 return clock->rate;
1319 if (clock->rate != rate) {
1320 usb_audio_err(chip, "Mismatched sample rate %d vs %d for EP 0x%x\n",
1321 clock->rate, rate, ep->ep_num);
1322 return clock->rate;
1323 }
1324 }
1325 clock->rate = rate;
1326 clock->need_setup = true;
1327 return rate;
1328}
1329
1330/*
1331 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
1332 *
1333 * It's called either from hw_params callback.
1334 * Determine the number of URBs to be used on this endpoint.
1335 * An endpoint must be configured before it can be started.
1336 * An endpoint that is already running can not be reconfigured.
1337 */
1338int snd_usb_endpoint_set_params(struct snd_usb_audio *chip,
1339 struct snd_usb_endpoint *ep)
1340{
1341 const struct audioformat *fmt = ep->cur_audiofmt;
1342 int err = 0;
1343
1344 mutex_lock(&chip->mutex);
1345 if (!ep->need_setup)
1346 goto unlock;
1347
1348 /* release old buffers, if any */
1349 err = release_urbs(ep, false);
1350 if (err < 0)
1351 goto unlock;
1352
1353 ep->datainterval = fmt->datainterval;
1354 ep->maxpacksize = fmt->maxpacksize;
1355 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
1356
1357 if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) {
1358 ep->freqn = get_usb_full_speed_rate(ep->cur_rate);
1359 ep->pps = 1000 >> ep->datainterval;
1360 } else {
1361 ep->freqn = get_usb_high_speed_rate(ep->cur_rate);
1362 ep->pps = 8000 >> ep->datainterval;
1363 }
1364
1365 ep->sample_rem = ep->cur_rate % ep->pps;
1366 ep->packsize[0] = ep->cur_rate / ep->pps;
1367 ep->packsize[1] = (ep->cur_rate + (ep->pps - 1)) / ep->pps;
1368
1369 /* calculate the frequency in 16.16 format */
1370 ep->freqm = ep->freqn;
1371 ep->freqshift = INT_MIN;
1372
1373 ep->phase = 0;
1374
1375 switch (ep->type) {
1376 case SND_USB_ENDPOINT_TYPE_DATA:
1377 err = data_ep_set_params(ep);
1378 break;
1379 case SND_USB_ENDPOINT_TYPE_SYNC:
1380 err = sync_ep_set_params(ep);
1381 break;
1382 default:
1383 err = -EINVAL;
1384 }
1385
1386 usb_audio_dbg(chip, "Set up %d URBS, ret=%d\n", ep->nurbs, err);
1387
1388 if (err < 0)
1389 goto unlock;
1390
1391 /* some unit conversions in runtime */
1392 ep->maxframesize = ep->maxpacksize / ep->cur_frame_bytes;
1393 ep->curframesize = ep->curpacksize / ep->cur_frame_bytes;
1394
1395 err = update_clock_ref_rate(chip, ep);
1396 if (err >= 0) {
1397 ep->need_setup = false;
1398 err = 0;
1399 }
1400
1401 unlock:
1402 mutex_unlock(&chip->mutex);
1403 return err;
1404}
1405
1406static int init_sample_rate(struct snd_usb_audio *chip,
1407 struct snd_usb_endpoint *ep)
1408{
1409 struct snd_usb_clock_ref *clock = ep->clock_ref;
1410 int rate, err;
1411
1412 rate = update_clock_ref_rate(chip, ep);
1413 if (rate < 0)
1414 return rate;
1415 if (clock && !clock->need_setup)
1416 return 0;
1417
1418 if (!ep->fixed_rate) {
1419 err = snd_usb_init_sample_rate(chip, ep->cur_audiofmt, rate);
1420 if (err < 0) {
1421 if (clock)
1422 clock->rate = 0; /* reset rate */
1423 return err;
1424 }
1425 }
1426
1427 if (clock)
1428 clock->need_setup = false;
1429 return 0;
1430}
1431
1432/*
1433 * snd_usb_endpoint_prepare: Prepare the endpoint
1434 *
1435 * This function sets up the EP to be fully usable state.
1436 * It's called either from prepare callback.
1437 * The function checks need_setup flag, and performs nothing unless needed,
1438 * so it's safe to call this multiple times.
1439 *
1440 * This returns zero if unchanged, 1 if the configuration has changed,
1441 * or a negative error code.
1442 */
1443int snd_usb_endpoint_prepare(struct snd_usb_audio *chip,
1444 struct snd_usb_endpoint *ep)
1445{
1446 bool iface_first;
1447 int err = 0;
1448
1449 mutex_lock(&chip->mutex);
1450 if (WARN_ON(!ep->iface_ref))
1451 goto unlock;
1452 if (!ep->need_prepare)
1453 goto unlock;
1454
1455 /* If the interface has been already set up, just set EP parameters */
1456 if (!ep->iface_ref->need_setup) {
1457 /* sample rate setup of UAC1 is per endpoint, and we need
1458 * to update at each EP configuration
1459 */
1460 if (ep->cur_audiofmt->protocol == UAC_VERSION_1) {
1461 err = init_sample_rate(chip, ep);
1462 if (err < 0)
1463 goto unlock;
1464 }
1465 goto done;
1466 }
1467
1468 /* Need to deselect altsetting at first */
1469 endpoint_set_interface(chip, ep, false);
1470
1471 /* Some UAC1 devices (e.g. Yamaha THR10) need the host interface
1472 * to be set up before parameter setups
1473 */
1474 iface_first = ep->cur_audiofmt->protocol == UAC_VERSION_1;
1475 /* Workaround for devices that require the interface setup at first like UAC1 */
1476 if (chip->quirk_flags & QUIRK_FLAG_SET_IFACE_FIRST)
1477 iface_first = true;
1478 if (iface_first) {
1479 err = endpoint_set_interface(chip, ep, true);
1480 if (err < 0)
1481 goto unlock;
1482 }
1483
1484 err = snd_usb_init_pitch(chip, ep->cur_audiofmt);
1485 if (err < 0)
1486 goto unlock;
1487
1488 err = init_sample_rate(chip, ep);
1489 if (err < 0)
1490 goto unlock;
1491
1492 err = snd_usb_select_mode_quirk(chip, ep->cur_audiofmt);
1493 if (err < 0)
1494 goto unlock;
1495
1496 /* for UAC2/3, enable the interface altset here at last */
1497 if (!iface_first) {
1498 err = endpoint_set_interface(chip, ep, true);
1499 if (err < 0)
1500 goto unlock;
1501 }
1502
1503 ep->iface_ref->need_setup = false;
1504
1505 done:
1506 ep->need_prepare = false;
1507 err = 1;
1508
1509unlock:
1510 mutex_unlock(&chip->mutex);
1511 return err;
1512}
1513
1514/* get the current rate set to the given clock by any endpoint */
1515int snd_usb_endpoint_get_clock_rate(struct snd_usb_audio *chip, int clock)
1516{
1517 struct snd_usb_clock_ref *ref;
1518 int rate = 0;
1519
1520 if (!clock)
1521 return 0;
1522 mutex_lock(&chip->mutex);
1523 list_for_each_entry(ref, &chip->clock_ref_list, list) {
1524 if (ref->clock == clock) {
1525 rate = ref->rate;
1526 break;
1527 }
1528 }
1529 mutex_unlock(&chip->mutex);
1530 return rate;
1531}
1532
1533/**
1534 * snd_usb_endpoint_start: start an snd_usb_endpoint
1535 *
1536 * @ep: the endpoint to start
1537 *
1538 * A call to this function will increment the running count of the endpoint.
1539 * In case it is not already running, the URBs for this endpoint will be
1540 * submitted. Otherwise, this function does nothing.
1541 *
1542 * Must be balanced to calls of snd_usb_endpoint_stop().
1543 *
1544 * Returns an error if the URB submission failed, 0 in all other cases.
1545 */
1546int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
1547{
1548 bool is_playback = usb_pipeout(ep->pipe);
1549 int err;
1550 unsigned int i;
1551
1552 if (atomic_read(&ep->chip->shutdown))
1553 return -EBADFD;
1554
1555 if (ep->sync_source)
1556 WRITE_ONCE(ep->sync_source->sync_sink, ep);
1557
1558 usb_audio_dbg(ep->chip, "Starting %s EP 0x%x (running %d)\n",
1559 ep_type_name(ep->type), ep->ep_num,
1560 atomic_read(&ep->running));
1561
1562 /* already running? */
1563 if (atomic_inc_return(&ep->running) != 1)
1564 return 0;
1565
1566 if (ep->clock_ref)
1567 atomic_inc(&ep->clock_ref->locked);
1568
1569 ep->active_mask = 0;
1570 ep->unlink_mask = 0;
1571 ep->phase = 0;
1572 ep->sample_accum = 0;
1573
1574 snd_usb_endpoint_start_quirk(ep);
1575
1576 /*
1577 * If this endpoint has a data endpoint as implicit feedback source,
1578 * don't start the urbs here. Instead, mark them all as available,
1579 * wait for the record urbs to return and queue the playback urbs
1580 * from that context.
1581 */
1582
1583 if (!ep_state_update(ep, EP_STATE_STOPPED, EP_STATE_RUNNING))
1584 goto __error;
1585
1586 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1587 !(ep->chip->quirk_flags & QUIRK_FLAG_PLAYBACK_FIRST)) {
1588 usb_audio_dbg(ep->chip, "No URB submission due to implicit fb sync\n");
1589 i = 0;
1590 goto fill_rest;
1591 }
1592
1593 for (i = 0; i < ep->nurbs; i++) {
1594 struct urb *urb = ep->urb[i].urb;
1595
1596 if (snd_BUG_ON(!urb))
1597 goto __error;
1598
1599 if (is_playback)
1600 err = prepare_outbound_urb(ep, urb->context, true);
1601 else
1602 err = prepare_inbound_urb(ep, urb->context);
1603 if (err < 0) {
1604 /* stop filling at applptr */
1605 if (err == -EAGAIN)
1606 break;
1607 usb_audio_dbg(ep->chip,
1608 "EP 0x%x: failed to prepare urb: %d\n",
1609 ep->ep_num, err);
1610 goto __error;
1611 }
1612
1613 err = usb_submit_urb(urb, GFP_ATOMIC);
1614 if (err < 0) {
1615 usb_audio_err(ep->chip,
1616 "cannot submit urb %d, error %d: %s\n",
1617 i, err, usb_error_string(err));
1618 goto __error;
1619 }
1620 set_bit(i, &ep->active_mask);
1621 atomic_inc(&ep->submitted_urbs);
1622 }
1623
1624 if (!i) {
1625 usb_audio_dbg(ep->chip, "XRUN at starting EP 0x%x\n",
1626 ep->ep_num);
1627 goto __error;
1628 }
1629
1630 usb_audio_dbg(ep->chip, "%d URBs submitted for EP 0x%x\n",
1631 i, ep->ep_num);
1632
1633 fill_rest:
1634 /* put the remaining URBs to ready list */
1635 if (is_playback) {
1636 for (; i < ep->nurbs; i++)
1637 push_back_to_ready_list(ep, ep->urb + i);
1638 }
1639
1640 return 0;
1641
1642__error:
1643 snd_usb_endpoint_stop(ep, false);
1644 return -EPIPE;
1645}
1646
1647/**
1648 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
1649 *
1650 * @ep: the endpoint to stop (may be NULL)
1651 * @keep_pending: keep in-flight URBs
1652 *
1653 * A call to this function will decrement the running count of the endpoint.
1654 * In case the last user has requested the endpoint stop, the URBs will
1655 * actually be deactivated.
1656 *
1657 * Must be balanced to calls of snd_usb_endpoint_start().
1658 *
1659 * The caller needs to synchronize the pending stop operation via
1660 * snd_usb_endpoint_sync_pending_stop().
1661 */
1662void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep, bool keep_pending)
1663{
1664 if (!ep)
1665 return;
1666
1667 usb_audio_dbg(ep->chip, "Stopping %s EP 0x%x (running %d)\n",
1668 ep_type_name(ep->type), ep->ep_num,
1669 atomic_read(&ep->running));
1670
1671 if (snd_BUG_ON(!atomic_read(&ep->running)))
1672 return;
1673
1674 if (!atomic_dec_return(&ep->running)) {
1675 if (ep->sync_source)
1676 WRITE_ONCE(ep->sync_source->sync_sink, NULL);
1677 stop_urbs(ep, false, keep_pending);
1678 if (ep->clock_ref)
1679 atomic_dec(&ep->clock_ref->locked);
1680
1681 if (ep->chip->quirk_flags & QUIRK_FLAG_FORCE_IFACE_RESET &&
1682 usb_pipeout(ep->pipe)) {
1683 ep->need_prepare = true;
1684 if (ep->iface_ref)
1685 ep->iface_ref->need_setup = true;
1686 }
1687 }
1688}
1689
1690/**
1691 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1692 *
1693 * @ep: the endpoint to release
1694 *
1695 * This function does not care for the endpoint's running count but will tear
1696 * down all the streaming URBs immediately.
1697 */
1698void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1699{
1700 release_urbs(ep, true);
1701}
1702
1703/**
1704 * snd_usb_endpoint_free_all: Free the resources of an snd_usb_endpoint
1705 * @chip: The chip
1706 *
1707 * This free all endpoints and those resources
1708 */
1709void snd_usb_endpoint_free_all(struct snd_usb_audio *chip)
1710{
1711 struct snd_usb_endpoint *ep, *en;
1712 struct snd_usb_iface_ref *ip, *in;
1713 struct snd_usb_clock_ref *cp, *cn;
1714
1715 list_for_each_entry_safe(ep, en, &chip->ep_list, list)
1716 kfree(ep);
1717
1718 list_for_each_entry_safe(ip, in, &chip->iface_ref_list, list)
1719 kfree(ip);
1720
1721 list_for_each_entry_safe(cp, cn, &chip->clock_ref_list, list)
1722 kfree(cp);
1723}
1724
1725/*
1726 * snd_usb_handle_sync_urb: parse an USB sync packet
1727 *
1728 * @ep: the endpoint to handle the packet
1729 * @sender: the sending endpoint
1730 * @urb: the received packet
1731 *
1732 * This function is called from the context of an endpoint that received
1733 * the packet and is used to let another endpoint object handle the payload.
1734 */
1735static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1736 struct snd_usb_endpoint *sender,
1737 const struct urb *urb)
1738{
1739 int shift;
1740 unsigned int f;
1741 unsigned long flags;
1742
1743 snd_BUG_ON(ep == sender);
1744
1745 /*
1746 * In case the endpoint is operating in implicit feedback mode, prepare
1747 * a new outbound URB that has the same layout as the received packet
1748 * and add it to the list of pending urbs. queue_pending_output_urbs()
1749 * will take care of them later.
1750 */
1751 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1752 atomic_read(&ep->running)) {
1753
1754 /* implicit feedback case */
1755 int i, bytes = 0;
1756 struct snd_urb_ctx *in_ctx;
1757 struct snd_usb_packet_info *out_packet;
1758
1759 in_ctx = urb->context;
1760
1761 /* Count overall packet size */
1762 for (i = 0; i < in_ctx->packets; i++)
1763 if (urb->iso_frame_desc[i].status == 0)
1764 bytes += urb->iso_frame_desc[i].actual_length;
1765
1766 /*
1767 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1768 * streaming once it received a 0-byte OUT URB
1769 */
1770 if (bytes == 0)
1771 return;
1772
1773 spin_lock_irqsave(&ep->lock, flags);
1774 if (ep->next_packet_queued >= ARRAY_SIZE(ep->next_packet)) {
1775 spin_unlock_irqrestore(&ep->lock, flags);
1776 usb_audio_err(ep->chip,
1777 "next package FIFO overflow EP 0x%x\n",
1778 ep->ep_num);
1779 notify_xrun(ep);
1780 return;
1781 }
1782
1783 out_packet = next_packet_fifo_enqueue(ep);
1784
1785 /*
1786 * Iterate through the inbound packet and prepare the lengths
1787 * for the output packet. The OUT packet we are about to send
1788 * will have the same amount of payload bytes per stride as the
1789 * IN packet we just received. Since the actual size is scaled
1790 * by the stride, use the sender stride to calculate the length
1791 * in case the number of channels differ between the implicitly
1792 * fed-back endpoint and the synchronizing endpoint.
1793 */
1794
1795 out_packet->packets = in_ctx->packets;
1796 for (i = 0; i < in_ctx->packets; i++) {
1797 if (urb->iso_frame_desc[i].status == 0)
1798 out_packet->packet_size[i] =
1799 urb->iso_frame_desc[i].actual_length / sender->stride;
1800 else
1801 out_packet->packet_size[i] = 0;
1802 }
1803
1804 spin_unlock_irqrestore(&ep->lock, flags);
1805 snd_usb_queue_pending_output_urbs(ep, false);
1806
1807 return;
1808 }
1809
1810 /*
1811 * process after playback sync complete
1812 *
1813 * Full speed devices report feedback values in 10.14 format as samples
1814 * per frame, high speed devices in 16.16 format as samples per
1815 * microframe.
1816 *
1817 * Because the Audio Class 1 spec was written before USB 2.0, many high
1818 * speed devices use a wrong interpretation, some others use an
1819 * entirely different format.
1820 *
1821 * Therefore, we cannot predict what format any particular device uses
1822 * and must detect it automatically.
1823 */
1824
1825 if (urb->iso_frame_desc[0].status != 0 ||
1826 urb->iso_frame_desc[0].actual_length < 3)
1827 return;
1828
1829 f = le32_to_cpup(urb->transfer_buffer);
1830 if (urb->iso_frame_desc[0].actual_length == 3)
1831 f &= 0x00ffffff;
1832 else
1833 f &= 0x0fffffff;
1834
1835 if (f == 0)
1836 return;
1837
1838 if (unlikely(sender->tenor_fb_quirk)) {
1839 /*
1840 * Devices based on Tenor 8802 chipsets (TEAC UD-H01
1841 * and others) sometimes change the feedback value
1842 * by +/- 0x1.0000.
1843 */
1844 if (f < ep->freqn - 0x8000)
1845 f += 0xf000;
1846 else if (f > ep->freqn + 0x8000)
1847 f -= 0xf000;
1848 } else if (unlikely(ep->freqshift == INT_MIN)) {
1849 /*
1850 * The first time we see a feedback value, determine its format
1851 * by shifting it left or right until it matches the nominal
1852 * frequency value. This assumes that the feedback does not
1853 * differ from the nominal value more than +50% or -25%.
1854 */
1855 shift = 0;
1856 while (f < ep->freqn - ep->freqn / 4) {
1857 f <<= 1;
1858 shift++;
1859 }
1860 while (f > ep->freqn + ep->freqn / 2) {
1861 f >>= 1;
1862 shift--;
1863 }
1864 ep->freqshift = shift;
1865 } else if (ep->freqshift >= 0)
1866 f <<= ep->freqshift;
1867 else
1868 f >>= -ep->freqshift;
1869
1870 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1871 /*
1872 * If the frequency looks valid, set it.
1873 * This value is referred to in prepare_playback_urb().
1874 */
1875 spin_lock_irqsave(&ep->lock, flags);
1876 ep->freqm = f;
1877 spin_unlock_irqrestore(&ep->lock, flags);
1878 } else {
1879 /*
1880 * Out of range; maybe the shift value is wrong.
1881 * Reset it so that we autodetect again the next time.
1882 */
1883 ep->freqshift = INT_MIN;
1884 }
1885}
1886