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