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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 next_packet_size() to
128 * determine the number of samples to be sent in the next packet.
129 *
130 * For implicit feedback, next_packet_size() is unused.
131 */
132int snd_usb_endpoint_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
149static void retire_outbound_urb(struct snd_usb_endpoint *ep,
150 struct snd_urb_ctx *urb_ctx)
151{
152 if (ep->retire_data_urb)
153 ep->retire_data_urb(ep->data_subs, urb_ctx->urb);
154}
155
156static void retire_inbound_urb(struct snd_usb_endpoint *ep,
157 struct snd_urb_ctx *urb_ctx)
158{
159 struct urb *urb = urb_ctx->urb;
160
161 if (unlikely(ep->skip_packets > 0)) {
162 ep->skip_packets--;
163 return;
164 }
165
166 if (ep->sync_slave)
167 snd_usb_handle_sync_urb(ep->sync_slave, ep, urb);
168
169 if (ep->retire_data_urb)
170 ep->retire_data_urb(ep->data_subs, urb);
171}
172
173static void prepare_silent_urb(struct snd_usb_endpoint *ep,
174 struct snd_urb_ctx *ctx)
175{
176 struct urb *urb = ctx->urb;
177 unsigned int offs = 0;
178 unsigned int extra = 0;
179 __le32 packet_length;
180 int i;
181
182 /* For tx_length_quirk, put packet length at start of packet */
183 if (ep->chip->tx_length_quirk)
184 extra = sizeof(packet_length);
185
186 for (i = 0; i < ctx->packets; ++i) {
187 unsigned int offset;
188 unsigned int length;
189 int counts;
190
191 if (ctx->packet_size[i])
192 counts = ctx->packet_size[i];
193 else
194 counts = snd_usb_endpoint_next_packet_size(ep);
195
196 length = counts * ep->stride; /* number of silent bytes */
197 offset = offs * ep->stride + extra * i;
198 urb->iso_frame_desc[i].offset = offset;
199 urb->iso_frame_desc[i].length = length + extra;
200 if (extra) {
201 packet_length = cpu_to_le32(length);
202 memcpy(urb->transfer_buffer + offset,
203 &packet_length, sizeof(packet_length));
204 }
205 memset(urb->transfer_buffer + offset + extra,
206 ep->silence_value, length);
207 offs += counts;
208 }
209
210 urb->number_of_packets = ctx->packets;
211 urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
212}
213
214/*
215 * Prepare a PLAYBACK urb for submission to the bus.
216 */
217static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
218 struct snd_urb_ctx *ctx)
219{
220 struct urb *urb = ctx->urb;
221 unsigned char *cp = urb->transfer_buffer;
222
223 urb->dev = ep->chip->dev; /* we need to set this at each time */
224
225 switch (ep->type) {
226 case SND_USB_ENDPOINT_TYPE_DATA:
227 if (ep->prepare_data_urb) {
228 ep->prepare_data_urb(ep->data_subs, urb);
229 } else {
230 /* no data provider, so send silence */
231 prepare_silent_urb(ep, ctx);
232 }
233 break;
234
235 case SND_USB_ENDPOINT_TYPE_SYNC:
236 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
237 /*
238 * fill the length and offset of each urb descriptor.
239 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
240 */
241 urb->iso_frame_desc[0].length = 4;
242 urb->iso_frame_desc[0].offset = 0;
243 cp[0] = ep->freqn;
244 cp[1] = ep->freqn >> 8;
245 cp[2] = ep->freqn >> 16;
246 cp[3] = ep->freqn >> 24;
247 } else {
248 /*
249 * fill the length and offset of each urb descriptor.
250 * the fixed 10.14 frequency is passed through the pipe.
251 */
252 urb->iso_frame_desc[0].length = 3;
253 urb->iso_frame_desc[0].offset = 0;
254 cp[0] = ep->freqn >> 2;
255 cp[1] = ep->freqn >> 10;
256 cp[2] = ep->freqn >> 18;
257 }
258
259 break;
260 }
261}
262
263/*
264 * Prepare a CAPTURE or SYNC urb for submission to the bus.
265 */
266static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep,
267 struct snd_urb_ctx *urb_ctx)
268{
269 int i, offs;
270 struct urb *urb = urb_ctx->urb;
271
272 urb->dev = ep->chip->dev; /* we need to set this at each time */
273
274 switch (ep->type) {
275 case SND_USB_ENDPOINT_TYPE_DATA:
276 offs = 0;
277 for (i = 0; i < urb_ctx->packets; i++) {
278 urb->iso_frame_desc[i].offset = offs;
279 urb->iso_frame_desc[i].length = ep->curpacksize;
280 offs += ep->curpacksize;
281 }
282
283 urb->transfer_buffer_length = offs;
284 urb->number_of_packets = urb_ctx->packets;
285 break;
286
287 case SND_USB_ENDPOINT_TYPE_SYNC:
288 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
289 urb->iso_frame_desc[0].offset = 0;
290 break;
291 }
292}
293
294/*
295 * Send output urbs that have been prepared previously. URBs are dequeued
296 * from ep->ready_playback_urbs and in case there there aren't any available
297 * or there are no packets that have been prepared, this function does
298 * nothing.
299 *
300 * The reason why the functionality of sending and preparing URBs is separated
301 * is that host controllers don't guarantee the order in which they return
302 * inbound and outbound packets to their submitters.
303 *
304 * This function is only used for implicit feedback endpoints. For endpoints
305 * driven by dedicated sync endpoints, URBs are immediately re-submitted
306 * from their completion handler.
307 */
308static void queue_pending_output_urbs(struct snd_usb_endpoint *ep)
309{
310 while (test_bit(EP_FLAG_RUNNING, &ep->flags)) {
311
312 unsigned long flags;
313 struct snd_usb_packet_info *uninitialized_var(packet);
314 struct snd_urb_ctx *ctx = NULL;
315 int err, i;
316
317 spin_lock_irqsave(&ep->lock, flags);
318 if (ep->next_packet_read_pos != ep->next_packet_write_pos) {
319 packet = ep->next_packet + ep->next_packet_read_pos;
320 ep->next_packet_read_pos++;
321 ep->next_packet_read_pos %= MAX_URBS;
322
323 /* take URB out of FIFO */
324 if (!list_empty(&ep->ready_playback_urbs))
325 ctx = list_first_entry(&ep->ready_playback_urbs,
326 struct snd_urb_ctx, ready_list);
327 }
328 spin_unlock_irqrestore(&ep->lock, flags);
329
330 if (ctx == NULL)
331 return;
332
333 list_del_init(&ctx->ready_list);
334
335 /* copy over the length information */
336 for (i = 0; i < packet->packets; i++)
337 ctx->packet_size[i] = packet->packet_size[i];
338
339 /* call the data handler to fill in playback data */
340 prepare_outbound_urb(ep, ctx);
341
342 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
343 if (err < 0)
344 usb_audio_err(ep->chip,
345 "Unable to submit urb #%d: %d (urb %p)\n",
346 ctx->index, err, ctx->urb);
347 else
348 set_bit(ctx->index, &ep->active_mask);
349 }
350}
351
352/*
353 * complete callback for urbs
354 */
355static void snd_complete_urb(struct urb *urb)
356{
357 struct snd_urb_ctx *ctx = urb->context;
358 struct snd_usb_endpoint *ep = ctx->ep;
359 struct snd_pcm_substream *substream;
360 unsigned long flags;
361 int err;
362
363 if (unlikely(urb->status == -ENOENT || /* unlinked */
364 urb->status == -ENODEV || /* device removed */
365 urb->status == -ECONNRESET || /* unlinked */
366 urb->status == -ESHUTDOWN)) /* device disabled */
367 goto exit_clear;
368 /* device disconnected */
369 if (unlikely(atomic_read(&ep->chip->shutdown)))
370 goto exit_clear;
371
372 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
373 goto exit_clear;
374
375 if (usb_pipeout(ep->pipe)) {
376 retire_outbound_urb(ep, ctx);
377 /* can be stopped during retire callback */
378 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
379 goto exit_clear;
380
381 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
382 spin_lock_irqsave(&ep->lock, flags);
383 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
384 spin_unlock_irqrestore(&ep->lock, flags);
385 queue_pending_output_urbs(ep);
386
387 goto exit_clear;
388 }
389
390 prepare_outbound_urb(ep, ctx);
391 /* can be stopped during prepare callback */
392 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
393 goto exit_clear;
394 } else {
395 retire_inbound_urb(ep, ctx);
396 /* can be stopped during retire callback */
397 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
398 goto exit_clear;
399
400 prepare_inbound_urb(ep, ctx);
401 }
402
403 err = usb_submit_urb(urb, GFP_ATOMIC);
404 if (err == 0)
405 return;
406
407 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
408 if (ep->data_subs && ep->data_subs->pcm_substream) {
409 substream = ep->data_subs->pcm_substream;
410 snd_pcm_stop_xrun(substream);
411 }
412
413exit_clear:
414 clear_bit(ctx->index, &ep->active_mask);
415}
416
417/**
418 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
419 *
420 * @chip: The chip
421 * @alts: The USB host interface
422 * @ep_num: The number of the endpoint to use
423 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
424 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
425 *
426 * If the requested endpoint has not been added to the given chip before,
427 * a new instance is created. Otherwise, a pointer to the previoulsy
428 * created instance is returned. In case of any error, NULL is returned.
429 *
430 * New endpoints will be added to chip->ep_list and must be freed by
431 * calling snd_usb_endpoint_free().
432 *
433 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
434 * bNumEndpoints > 1 beforehand.
435 */
436struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
437 struct usb_host_interface *alts,
438 int ep_num, int direction, int type)
439{
440 struct snd_usb_endpoint *ep;
441 int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK;
442
443 if (WARN_ON(!alts))
444 return NULL;
445
446 mutex_lock(&chip->mutex);
447
448 list_for_each_entry(ep, &chip->ep_list, list) {
449 if (ep->ep_num == ep_num &&
450 ep->iface == alts->desc.bInterfaceNumber &&
451 ep->altsetting == alts->desc.bAlternateSetting) {
452 usb_audio_dbg(ep->chip,
453 "Re-using EP %x in iface %d,%d @%p\n",
454 ep_num, ep->iface, ep->altsetting, ep);
455 goto __exit_unlock;
456 }
457 }
458
459 usb_audio_dbg(chip, "Creating new %s %s endpoint #%x\n",
460 is_playback ? "playback" : "capture",
461 type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync",
462 ep_num);
463
464 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
465 if (!ep)
466 goto __exit_unlock;
467
468 ep->chip = chip;
469 spin_lock_init(&ep->lock);
470 ep->type = type;
471 ep->ep_num = ep_num;
472 ep->iface = alts->desc.bInterfaceNumber;
473 ep->altsetting = alts->desc.bAlternateSetting;
474 INIT_LIST_HEAD(&ep->ready_playback_urbs);
475 ep_num &= USB_ENDPOINT_NUMBER_MASK;
476
477 if (is_playback)
478 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
479 else
480 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
481
482 if (type == SND_USB_ENDPOINT_TYPE_SYNC) {
483 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
484 get_endpoint(alts, 1)->bRefresh >= 1 &&
485 get_endpoint(alts, 1)->bRefresh <= 9)
486 ep->syncinterval = get_endpoint(alts, 1)->bRefresh;
487 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
488 ep->syncinterval = 1;
489 else if (get_endpoint(alts, 1)->bInterval >= 1 &&
490 get_endpoint(alts, 1)->bInterval <= 16)
491 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1;
492 else
493 ep->syncinterval = 3;
494
495 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize);
496 }
497
498 list_add_tail(&ep->list, &chip->ep_list);
499
500__exit_unlock:
501 mutex_unlock(&chip->mutex);
502
503 return ep;
504}
505
506/*
507 * wait until all urbs are processed.
508 */
509static int wait_clear_urbs(struct snd_usb_endpoint *ep)
510{
511 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
512 int alive;
513
514 do {
515 alive = bitmap_weight(&ep->active_mask, ep->nurbs);
516 if (!alive)
517 break;
518
519 schedule_timeout_uninterruptible(1);
520 } while (time_before(jiffies, end_time));
521
522 if (alive)
523 usb_audio_err(ep->chip,
524 "timeout: still %d active urbs on EP #%x\n",
525 alive, ep->ep_num);
526 clear_bit(EP_FLAG_STOPPING, &ep->flags);
527
528 ep->data_subs = NULL;
529 ep->sync_slave = NULL;
530 ep->retire_data_urb = NULL;
531 ep->prepare_data_urb = NULL;
532
533 return 0;
534}
535
536/* sync the pending stop operation;
537 * this function itself doesn't trigger the stop operation
538 */
539void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
540{
541 if (ep && test_bit(EP_FLAG_STOPPING, &ep->flags))
542 wait_clear_urbs(ep);
543}
544
545/*
546 * unlink active urbs.
547 */
548static int deactivate_urbs(struct snd_usb_endpoint *ep, bool force)
549{
550 unsigned int i;
551
552 if (!force && atomic_read(&ep->chip->shutdown)) /* to be sure... */
553 return -EBADFD;
554
555 clear_bit(EP_FLAG_RUNNING, &ep->flags);
556
557 INIT_LIST_HEAD(&ep->ready_playback_urbs);
558 ep->next_packet_read_pos = 0;
559 ep->next_packet_write_pos = 0;
560
561 for (i = 0; i < ep->nurbs; i++) {
562 if (test_bit(i, &ep->active_mask)) {
563 if (!test_and_set_bit(i, &ep->unlink_mask)) {
564 struct urb *u = ep->urb[i].urb;
565 usb_unlink_urb(u);
566 }
567 }
568 }
569
570 return 0;
571}
572
573/*
574 * release an endpoint's urbs
575 */
576static void release_urbs(struct snd_usb_endpoint *ep, int force)
577{
578 int i;
579
580 /* route incoming urbs to nirvana */
581 ep->retire_data_urb = NULL;
582 ep->prepare_data_urb = NULL;
583
584 /* stop urbs */
585 deactivate_urbs(ep, force);
586 wait_clear_urbs(ep);
587
588 for (i = 0; i < ep->nurbs; i++)
589 release_urb_ctx(&ep->urb[i]);
590
591 if (ep->syncbuf)
592 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
593 ep->syncbuf, ep->sync_dma);
594
595 ep->syncbuf = NULL;
596 ep->nurbs = 0;
597}
598
599/*
600 * configure a data endpoint
601 */
602static int data_ep_set_params(struct snd_usb_endpoint *ep,
603 snd_pcm_format_t pcm_format,
604 unsigned int channels,
605 unsigned int period_bytes,
606 unsigned int frames_per_period,
607 unsigned int periods_per_buffer,
608 struct audioformat *fmt,
609 struct snd_usb_endpoint *sync_ep)
610{
611 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
612 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
613 unsigned int max_urbs, i;
614 int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels;
615 int tx_length_quirk = (ep->chip->tx_length_quirk &&
616 usb_pipeout(ep->pipe));
617
618 if (pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
619 /*
620 * When operating in DSD DOP mode, the size of a sample frame
621 * in hardware differs from the actual physical format width
622 * because we need to make room for the DOP markers.
623 */
624 frame_bits += channels << 3;
625 }
626
627 ep->datainterval = fmt->datainterval;
628 ep->stride = frame_bits >> 3;
629
630 switch (pcm_format) {
631 case SNDRV_PCM_FORMAT_U8:
632 ep->silence_value = 0x80;
633 break;
634 case SNDRV_PCM_FORMAT_DSD_U8:
635 case SNDRV_PCM_FORMAT_DSD_U16_LE:
636 case SNDRV_PCM_FORMAT_DSD_U32_LE:
637 case SNDRV_PCM_FORMAT_DSD_U16_BE:
638 case SNDRV_PCM_FORMAT_DSD_U32_BE:
639 ep->silence_value = 0x69;
640 break;
641 default:
642 ep->silence_value = 0;
643 }
644
645 /* assume max. frequency is 50% higher than nominal */
646 ep->freqmax = ep->freqn + (ep->freqn >> 1);
647 /* Round up freqmax to nearest integer in order to calculate maximum
648 * packet size, which must represent a whole number of frames.
649 * This is accomplished by adding 0x0.ffff before converting the
650 * Q16.16 format into integer.
651 * In order to accurately calculate the maximum packet size when
652 * the data interval is more than 1 (i.e. ep->datainterval > 0),
653 * multiply by the data interval prior to rounding. For instance,
654 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
655 * frames with a data interval of 1, but 11 (10.25) frames with a
656 * data interval of 2.
657 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
658 * maximum datainterval value of 3, at USB full speed, higher for
659 * USB high speed, noting that ep->freqmax is in units of
660 * frames per packet in Q16.16 format.)
661 */
662 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
663 (frame_bits >> 3);
664 if (tx_length_quirk)
665 maxsize += sizeof(__le32); /* Space for length descriptor */
666 /* but wMaxPacketSize might reduce this */
667 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
668 /* whatever fits into a max. size packet */
669 unsigned int data_maxsize = maxsize = ep->maxpacksize;
670
671 if (tx_length_quirk)
672 /* Need to remove the length descriptor to calc freq */
673 data_maxsize -= sizeof(__le32);
674 ep->freqmax = (data_maxsize / (frame_bits >> 3))
675 << (16 - ep->datainterval);
676 }
677
678 if (ep->fill_max)
679 ep->curpacksize = ep->maxpacksize;
680 else
681 ep->curpacksize = maxsize;
682
683 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) {
684 packs_per_ms = 8 >> ep->datainterval;
685 max_packs_per_urb = MAX_PACKS_HS;
686 } else {
687 packs_per_ms = 1;
688 max_packs_per_urb = MAX_PACKS;
689 }
690 if (sync_ep && !snd_usb_endpoint_implicit_feedback_sink(ep))
691 max_packs_per_urb = min(max_packs_per_urb,
692 1U << sync_ep->syncinterval);
693 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
694
695 /*
696 * Capture endpoints need to use small URBs because there's no way
697 * to tell in advance where the next period will end, and we don't
698 * want the next URB to complete much after the period ends.
699 *
700 * Playback endpoints with implicit sync much use the same parameters
701 * as their corresponding capture endpoint.
702 */
703 if (usb_pipein(ep->pipe) ||
704 snd_usb_endpoint_implicit_feedback_sink(ep)) {
705
706 urb_packs = packs_per_ms;
707 /*
708 * Wireless devices can poll at a max rate of once per 4ms.
709 * For dataintervals less than 5, increase the packet count to
710 * allow the host controller to use bursting to fill in the
711 * gaps.
712 */
713 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_WIRELESS) {
714 int interval = ep->datainterval;
715 while (interval < 5) {
716 urb_packs <<= 1;
717 ++interval;
718 }
719 }
720 /* make capture URBs <= 1 ms and smaller than a period */
721 urb_packs = min(max_packs_per_urb, urb_packs);
722 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
723 urb_packs >>= 1;
724 ep->nurbs = MAX_URBS;
725
726 /*
727 * Playback endpoints without implicit sync are adjusted so that
728 * a period fits as evenly as possible in the smallest number of
729 * URBs. The total number of URBs is adjusted to the size of the
730 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
731 */
732 } else {
733 /* determine how small a packet can be */
734 minsize = (ep->freqn >> (16 - ep->datainterval)) *
735 (frame_bits >> 3);
736 /* with sync from device, assume it can be 12% lower */
737 if (sync_ep)
738 minsize -= minsize >> 3;
739 minsize = max(minsize, 1u);
740
741 /* how many packets will contain an entire ALSA period? */
742 max_packs_per_period = DIV_ROUND_UP(period_bytes, minsize);
743
744 /* how many URBs will contain a period? */
745 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
746 max_packs_per_urb);
747 /* how many packets are needed in each URB? */
748 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
749
750 /* limit the number of frames in a single URB */
751 ep->max_urb_frames = DIV_ROUND_UP(frames_per_period,
752 urbs_per_period);
753
754 /* try to use enough URBs to contain an entire ALSA buffer */
755 max_urbs = min((unsigned) MAX_URBS,
756 MAX_QUEUE * packs_per_ms / urb_packs);
757 ep->nurbs = min(max_urbs, urbs_per_period * periods_per_buffer);
758 }
759
760 /* allocate and initialize data urbs */
761 for (i = 0; i < ep->nurbs; i++) {
762 struct snd_urb_ctx *u = &ep->urb[i];
763 u->index = i;
764 u->ep = ep;
765 u->packets = urb_packs;
766 u->buffer_size = maxsize * u->packets;
767
768 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
769 u->packets++; /* for transfer delimiter */
770 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
771 if (!u->urb)
772 goto out_of_memory;
773
774 u->urb->transfer_buffer =
775 usb_alloc_coherent(ep->chip->dev, u->buffer_size,
776 GFP_KERNEL, &u->urb->transfer_dma);
777 if (!u->urb->transfer_buffer)
778 goto out_of_memory;
779 u->urb->pipe = ep->pipe;
780 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
781 u->urb->interval = 1 << ep->datainterval;
782 u->urb->context = u;
783 u->urb->complete = snd_complete_urb;
784 INIT_LIST_HEAD(&u->ready_list);
785 }
786
787 return 0;
788
789out_of_memory:
790 release_urbs(ep, 0);
791 return -ENOMEM;
792}
793
794/*
795 * configure a sync endpoint
796 */
797static int sync_ep_set_params(struct snd_usb_endpoint *ep)
798{
799 int i;
800
801 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4,
802 GFP_KERNEL, &ep->sync_dma);
803 if (!ep->syncbuf)
804 return -ENOMEM;
805
806 for (i = 0; i < SYNC_URBS; i++) {
807 struct snd_urb_ctx *u = &ep->urb[i];
808 u->index = i;
809 u->ep = ep;
810 u->packets = 1;
811 u->urb = usb_alloc_urb(1, GFP_KERNEL);
812 if (!u->urb)
813 goto out_of_memory;
814 u->urb->transfer_buffer = ep->syncbuf + i * 4;
815 u->urb->transfer_dma = ep->sync_dma + i * 4;
816 u->urb->transfer_buffer_length = 4;
817 u->urb->pipe = ep->pipe;
818 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
819 u->urb->number_of_packets = 1;
820 u->urb->interval = 1 << ep->syncinterval;
821 u->urb->context = u;
822 u->urb->complete = snd_complete_urb;
823 }
824
825 ep->nurbs = SYNC_URBS;
826
827 return 0;
828
829out_of_memory:
830 release_urbs(ep, 0);
831 return -ENOMEM;
832}
833
834/**
835 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
836 *
837 * @ep: the snd_usb_endpoint to configure
838 * @pcm_format: the audio fomat.
839 * @channels: the number of audio channels.
840 * @period_bytes: the number of bytes in one alsa period.
841 * @period_frames: the number of frames in one alsa period.
842 * @buffer_periods: the number of periods in one alsa buffer.
843 * @rate: the frame rate.
844 * @fmt: the USB audio format information
845 * @sync_ep: the sync endpoint to use, if any
846 *
847 * Determine the number of URBs to be used on this endpoint.
848 * An endpoint must be configured before it can be started.
849 * An endpoint that is already running can not be reconfigured.
850 */
851int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
852 snd_pcm_format_t pcm_format,
853 unsigned int channels,
854 unsigned int period_bytes,
855 unsigned int period_frames,
856 unsigned int buffer_periods,
857 unsigned int rate,
858 struct audioformat *fmt,
859 struct snd_usb_endpoint *sync_ep)
860{
861 int err;
862
863 if (ep->use_count != 0) {
864 usb_audio_warn(ep->chip,
865 "Unable to change format on ep #%x: already in use\n",
866 ep->ep_num);
867 return -EBUSY;
868 }
869
870 /* release old buffers, if any */
871 release_urbs(ep, 0);
872
873 ep->datainterval = fmt->datainterval;
874 ep->maxpacksize = fmt->maxpacksize;
875 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
876
877 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL)
878 ep->freqn = get_usb_full_speed_rate(rate);
879 else
880 ep->freqn = get_usb_high_speed_rate(rate);
881
882 /* calculate the frequency in 16.16 format */
883 ep->freqm = ep->freqn;
884 ep->freqshift = INT_MIN;
885
886 ep->phase = 0;
887
888 switch (ep->type) {
889 case SND_USB_ENDPOINT_TYPE_DATA:
890 err = data_ep_set_params(ep, pcm_format, channels,
891 period_bytes, period_frames,
892 buffer_periods, fmt, sync_ep);
893 break;
894 case SND_USB_ENDPOINT_TYPE_SYNC:
895 err = sync_ep_set_params(ep);
896 break;
897 default:
898 err = -EINVAL;
899 }
900
901 usb_audio_dbg(ep->chip,
902 "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
903 ep->ep_num, ep->type, ep->nurbs, err);
904
905 return err;
906}
907
908/**
909 * snd_usb_endpoint_start: start an snd_usb_endpoint
910 *
911 * @ep: the endpoint to start
912 *
913 * A call to this function will increment the use count of the endpoint.
914 * In case it is not already running, the URBs for this endpoint will be
915 * submitted. Otherwise, this function does nothing.
916 *
917 * Must be balanced to calls of snd_usb_endpoint_stop().
918 *
919 * Returns an error if the URB submission failed, 0 in all other cases.
920 */
921int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
922{
923 int err;
924 unsigned int i;
925
926 if (atomic_read(&ep->chip->shutdown))
927 return -EBADFD;
928
929 /* already running? */
930 if (++ep->use_count != 1)
931 return 0;
932
933 /* just to be sure */
934 deactivate_urbs(ep, false);
935
936 ep->active_mask = 0;
937 ep->unlink_mask = 0;
938 ep->phase = 0;
939
940 snd_usb_endpoint_start_quirk(ep);
941
942 /*
943 * If this endpoint has a data endpoint as implicit feedback source,
944 * don't start the urbs here. Instead, mark them all as available,
945 * wait for the record urbs to return and queue the playback urbs
946 * from that context.
947 */
948
949 set_bit(EP_FLAG_RUNNING, &ep->flags);
950
951 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
952 for (i = 0; i < ep->nurbs; i++) {
953 struct snd_urb_ctx *ctx = ep->urb + i;
954 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
955 }
956
957 return 0;
958 }
959
960 for (i = 0; i < ep->nurbs; i++) {
961 struct urb *urb = ep->urb[i].urb;
962
963 if (snd_BUG_ON(!urb))
964 goto __error;
965
966 if (usb_pipeout(ep->pipe)) {
967 prepare_outbound_urb(ep, urb->context);
968 } else {
969 prepare_inbound_urb(ep, urb->context);
970 }
971
972 err = usb_submit_urb(urb, GFP_ATOMIC);
973 if (err < 0) {
974 usb_audio_err(ep->chip,
975 "cannot submit urb %d, error %d: %s\n",
976 i, err, usb_error_string(err));
977 goto __error;
978 }
979 set_bit(i, &ep->active_mask);
980 }
981
982 return 0;
983
984__error:
985 clear_bit(EP_FLAG_RUNNING, &ep->flags);
986 ep->use_count--;
987 deactivate_urbs(ep, false);
988 return -EPIPE;
989}
990
991/**
992 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
993 *
994 * @ep: the endpoint to stop (may be NULL)
995 *
996 * A call to this function will decrement the use count of the endpoint.
997 * In case the last user has requested the endpoint stop, the URBs will
998 * actually be deactivated.
999 *
1000 * Must be balanced to calls of snd_usb_endpoint_start().
1001 *
1002 * The caller needs to synchronize the pending stop operation via
1003 * snd_usb_endpoint_sync_pending_stop().
1004 */
1005void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep)
1006{
1007 if (!ep)
1008 return;
1009
1010 if (snd_BUG_ON(ep->use_count == 0))
1011 return;
1012
1013 if (--ep->use_count == 0) {
1014 deactivate_urbs(ep, false);
1015 set_bit(EP_FLAG_STOPPING, &ep->flags);
1016 }
1017}
1018
1019/**
1020 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
1021 *
1022 * @ep: the endpoint to deactivate
1023 *
1024 * If the endpoint is not currently in use, this functions will
1025 * deactivate its associated URBs.
1026 *
1027 * In case of any active users, this functions does nothing.
1028 */
1029void snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep)
1030{
1031 if (!ep)
1032 return;
1033
1034 if (ep->use_count != 0)
1035 return;
1036
1037 deactivate_urbs(ep, true);
1038 wait_clear_urbs(ep);
1039}
1040
1041/**
1042 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1043 *
1044 * @ep: the endpoint to release
1045 *
1046 * This function does not care for the endpoint's use count but will tear
1047 * down all the streaming URBs immediately.
1048 */
1049void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1050{
1051 release_urbs(ep, 1);
1052}
1053
1054/**
1055 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
1056 *
1057 * @ep: the endpoint to free
1058 *
1059 * This free all resources of the given ep.
1060 */
1061void snd_usb_endpoint_free(struct snd_usb_endpoint *ep)
1062{
1063 kfree(ep);
1064}
1065
1066/**
1067 * snd_usb_handle_sync_urb: parse an USB sync packet
1068 *
1069 * @ep: the endpoint to handle the packet
1070 * @sender: the sending endpoint
1071 * @urb: the received packet
1072 *
1073 * This function is called from the context of an endpoint that received
1074 * the packet and is used to let another endpoint object handle the payload.
1075 */
1076void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1077 struct snd_usb_endpoint *sender,
1078 const struct urb *urb)
1079{
1080 int shift;
1081 unsigned int f;
1082 unsigned long flags;
1083
1084 snd_BUG_ON(ep == sender);
1085
1086 /*
1087 * In case the endpoint is operating in implicit feedback mode, prepare
1088 * a new outbound URB that has the same layout as the received packet
1089 * and add it to the list of pending urbs. queue_pending_output_urbs()
1090 * will take care of them later.
1091 */
1092 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1093 ep->use_count != 0) {
1094
1095 /* implicit feedback case */
1096 int i, bytes = 0;
1097 struct snd_urb_ctx *in_ctx;
1098 struct snd_usb_packet_info *out_packet;
1099
1100 in_ctx = urb->context;
1101
1102 /* Count overall packet size */
1103 for (i = 0; i < in_ctx->packets; i++)
1104 if (urb->iso_frame_desc[i].status == 0)
1105 bytes += urb->iso_frame_desc[i].actual_length;
1106
1107 /*
1108 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1109 * streaming once it received a 0-byte OUT URB
1110 */
1111 if (bytes == 0)
1112 return;
1113
1114 spin_lock_irqsave(&ep->lock, flags);
1115 out_packet = ep->next_packet + ep->next_packet_write_pos;
1116
1117 /*
1118 * Iterate through the inbound packet and prepare the lengths
1119 * for the output packet. The OUT packet we are about to send
1120 * will have the same amount of payload bytes per stride as the
1121 * IN packet we just received. Since the actual size is scaled
1122 * by the stride, use the sender stride to calculate the length
1123 * in case the number of channels differ between the implicitly
1124 * fed-back endpoint and the synchronizing endpoint.
1125 */
1126
1127 out_packet->packets = in_ctx->packets;
1128 for (i = 0; i < in_ctx->packets; i++) {
1129 if (urb->iso_frame_desc[i].status == 0)
1130 out_packet->packet_size[i] =
1131 urb->iso_frame_desc[i].actual_length / sender->stride;
1132 else
1133 out_packet->packet_size[i] = 0;
1134 }
1135
1136 ep->next_packet_write_pos++;
1137 ep->next_packet_write_pos %= MAX_URBS;
1138 spin_unlock_irqrestore(&ep->lock, flags);
1139 queue_pending_output_urbs(ep);
1140
1141 return;
1142 }
1143
1144 /*
1145 * process after playback sync complete
1146 *
1147 * Full speed devices report feedback values in 10.14 format as samples
1148 * per frame, high speed devices in 16.16 format as samples per
1149 * microframe.
1150 *
1151 * Because the Audio Class 1 spec was written before USB 2.0, many high
1152 * speed devices use a wrong interpretation, some others use an
1153 * entirely different format.
1154 *
1155 * Therefore, we cannot predict what format any particular device uses
1156 * and must detect it automatically.
1157 */
1158
1159 if (urb->iso_frame_desc[0].status != 0 ||
1160 urb->iso_frame_desc[0].actual_length < 3)
1161 return;
1162
1163 f = le32_to_cpup(urb->transfer_buffer);
1164 if (urb->iso_frame_desc[0].actual_length == 3)
1165 f &= 0x00ffffff;
1166 else
1167 f &= 0x0fffffff;
1168
1169 if (f == 0)
1170 return;
1171
1172 if (unlikely(sender->tenor_fb_quirk)) {
1173 /*
1174 * Devices based on Tenor 8802 chipsets (TEAC UD-H01
1175 * and others) sometimes change the feedback value
1176 * by +/- 0x1.0000.
1177 */
1178 if (f < ep->freqn - 0x8000)
1179 f += 0xf000;
1180 else if (f > ep->freqn + 0x8000)
1181 f -= 0xf000;
1182 } else if (unlikely(ep->freqshift == INT_MIN)) {
1183 /*
1184 * The first time we see a feedback value, determine its format
1185 * by shifting it left or right until it matches the nominal
1186 * frequency value. This assumes that the feedback does not
1187 * differ from the nominal value more than +50% or -25%.
1188 */
1189 shift = 0;
1190 while (f < ep->freqn - ep->freqn / 4) {
1191 f <<= 1;
1192 shift++;
1193 }
1194 while (f > ep->freqn + ep->freqn / 2) {
1195 f >>= 1;
1196 shift--;
1197 }
1198 ep->freqshift = shift;
1199 } else if (ep->freqshift >= 0)
1200 f <<= ep->freqshift;
1201 else
1202 f >>= -ep->freqshift;
1203
1204 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1205 /*
1206 * If the frequency looks valid, set it.
1207 * This value is referred to in prepare_playback_urb().
1208 */
1209 spin_lock_irqsave(&ep->lock, flags);
1210 ep->freqm = f;
1211 spin_unlock_irqrestore(&ep->lock, flags);
1212 } else {
1213 /*
1214 * Out of range; maybe the shift value is wrong.
1215 * Reset it so that we autodetect again the next time.
1216 */
1217 ep->freqshift = INT_MIN;
1218 }
1219}
1220
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 */
4
5#include <linux/gfp.h>
6#include <linux/init.h>
7#include <linux/ratelimit.h>
8#include <linux/usb.h>
9#include <linux/usb/audio.h>
10#include <linux/slab.h>
11
12#include <sound/core.h>
13#include <sound/pcm.h>
14#include <sound/pcm_params.h>
15
16#include "usbaudio.h"
17#include "helper.h"
18#include "card.h"
19#include "endpoint.h"
20#include "pcm.h"
21#include "clock.h"
22#include "quirks.h"
23
24enum {
25 EP_STATE_STOPPED,
26 EP_STATE_RUNNING,
27 EP_STATE_STOPPING,
28};
29
30/* interface refcounting */
31struct snd_usb_iface_ref {
32 unsigned char iface;
33 bool need_setup;
34 int opened;
35 int altset;
36 struct list_head list;
37};
38
39/* clock refcounting */
40struct snd_usb_clock_ref {
41 unsigned char clock;
42 atomic_t locked;
43 int opened;
44 int rate;
45 bool need_setup;
46 struct list_head list;
47};
48
49/*
50 * snd_usb_endpoint is a model that abstracts everything related to an
51 * USB endpoint and its streaming.
52 *
53 * There are functions to activate and deactivate the streaming URBs and
54 * optional callbacks to let the pcm logic handle the actual content of the
55 * packets for playback and record. Thus, the bus streaming and the audio
56 * handlers are fully decoupled.
57 *
58 * There are two different types of endpoints in audio applications.
59 *
60 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
61 * inbound and outbound traffic.
62 *
63 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
64 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
65 * (3 or 4 bytes).
66 *
67 * Each endpoint has to be configured prior to being used by calling
68 * snd_usb_endpoint_set_params().
69 *
70 * The model incorporates a reference counting, so that multiple users
71 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
72 * only the first user will effectively start the URBs, and only the last
73 * one to stop it will tear the URBs down again.
74 */
75
76/*
77 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
78 * this will overflow at approx 524 kHz
79 */
80static inline unsigned get_usb_full_speed_rate(unsigned int rate)
81{
82 return ((rate << 13) + 62) / 125;
83}
84
85/*
86 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
87 * this will overflow at approx 4 MHz
88 */
89static inline unsigned get_usb_high_speed_rate(unsigned int rate)
90{
91 return ((rate << 10) + 62) / 125;
92}
93
94/*
95 * release a urb data
96 */
97static void release_urb_ctx(struct snd_urb_ctx *u)
98{
99 if (u->urb && u->buffer_size)
100 usb_free_coherent(u->ep->chip->dev, u->buffer_size,
101 u->urb->transfer_buffer,
102 u->urb->transfer_dma);
103 usb_free_urb(u->urb);
104 u->urb = NULL;
105 u->buffer_size = 0;
106}
107
108static const char *usb_error_string(int err)
109{
110 switch (err) {
111 case -ENODEV:
112 return "no device";
113 case -ENOENT:
114 return "endpoint not enabled";
115 case -EPIPE:
116 return "endpoint stalled";
117 case -ENOSPC:
118 return "not enough bandwidth";
119 case -ESHUTDOWN:
120 return "device disabled";
121 case -EHOSTUNREACH:
122 return "device suspended";
123 case -EINVAL:
124 case -EAGAIN:
125 case -EFBIG:
126 case -EMSGSIZE:
127 return "internal error";
128 default:
129 return "unknown error";
130 }
131}
132
133static inline bool ep_state_running(struct snd_usb_endpoint *ep)
134{
135 return atomic_read(&ep->state) == EP_STATE_RUNNING;
136}
137
138static inline bool ep_state_update(struct snd_usb_endpoint *ep, int old, int new)
139{
140 return atomic_try_cmpxchg(&ep->state, &old, new);
141}
142
143/**
144 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
145 *
146 * @ep: The snd_usb_endpoint
147 *
148 * Determine whether an endpoint is driven by an implicit feedback
149 * data endpoint source.
150 */
151int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
152{
153 return ep->implicit_fb_sync && usb_pipeout(ep->pipe);
154}
155
156/*
157 * Return the number of samples to be sent in the next packet
158 * for streaming based on information derived from sync endpoints
159 *
160 * This won't be used for implicit feedback which takes the packet size
161 * returned from the sync source
162 */
163static int slave_next_packet_size(struct snd_usb_endpoint *ep,
164 unsigned int avail)
165{
166 unsigned long flags;
167 unsigned int phase;
168 int ret;
169
170 if (ep->fill_max)
171 return ep->maxframesize;
172
173 spin_lock_irqsave(&ep->lock, flags);
174 phase = (ep->phase & 0xffff) + (ep->freqm << ep->datainterval);
175 ret = min(phase >> 16, ep->maxframesize);
176 if (avail && ret >= avail)
177 ret = -EAGAIN;
178 else
179 ep->phase = phase;
180 spin_unlock_irqrestore(&ep->lock, flags);
181
182 return ret;
183}
184
185/*
186 * Return the number of samples to be sent in the next packet
187 * for adaptive and synchronous endpoints
188 */
189static int next_packet_size(struct snd_usb_endpoint *ep, unsigned int avail)
190{
191 unsigned int sample_accum;
192 int ret;
193
194 if (ep->fill_max)
195 return ep->maxframesize;
196
197 sample_accum = ep->sample_accum + ep->sample_rem;
198 if (sample_accum >= ep->pps) {
199 sample_accum -= ep->pps;
200 ret = ep->packsize[1];
201 } else {
202 ret = ep->packsize[0];
203 }
204 if (avail && ret >= avail)
205 ret = -EAGAIN;
206 else
207 ep->sample_accum = sample_accum;
208
209 return ret;
210}
211
212/*
213 * snd_usb_endpoint_next_packet_size: Return the number of samples to be sent
214 * in the next packet
215 *
216 * If the size is equal or exceeds @avail, don't proceed but return -EAGAIN
217 * Exception: @avail = 0 for skipping the check.
218 */
219int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep,
220 struct snd_urb_ctx *ctx, int idx,
221 unsigned int avail)
222{
223 unsigned int packet;
224
225 packet = ctx->packet_size[idx];
226 if (packet) {
227 if (avail && packet >= avail)
228 return -EAGAIN;
229 return packet;
230 }
231
232 if (ep->sync_source)
233 return slave_next_packet_size(ep, avail);
234 else
235 return next_packet_size(ep, avail);
236}
237
238static void call_retire_callback(struct snd_usb_endpoint *ep,
239 struct urb *urb)
240{
241 struct snd_usb_substream *data_subs;
242
243 data_subs = READ_ONCE(ep->data_subs);
244 if (data_subs && ep->retire_data_urb)
245 ep->retire_data_urb(data_subs, urb);
246}
247
248static void retire_outbound_urb(struct snd_usb_endpoint *ep,
249 struct snd_urb_ctx *urb_ctx)
250{
251 call_retire_callback(ep, urb_ctx->urb);
252}
253
254static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
255 struct snd_usb_endpoint *sender,
256 const struct urb *urb);
257
258static void retire_inbound_urb(struct snd_usb_endpoint *ep,
259 struct snd_urb_ctx *urb_ctx)
260{
261 struct urb *urb = urb_ctx->urb;
262 struct snd_usb_endpoint *sync_sink;
263
264 if (unlikely(ep->skip_packets > 0)) {
265 ep->skip_packets--;
266 return;
267 }
268
269 sync_sink = READ_ONCE(ep->sync_sink);
270 if (sync_sink)
271 snd_usb_handle_sync_urb(sync_sink, ep, urb);
272
273 call_retire_callback(ep, urb);
274}
275
276static inline bool has_tx_length_quirk(struct snd_usb_audio *chip)
277{
278 return chip->quirk_flags & QUIRK_FLAG_TX_LENGTH;
279}
280
281static void prepare_silent_urb(struct snd_usb_endpoint *ep,
282 struct snd_urb_ctx *ctx)
283{
284 struct urb *urb = ctx->urb;
285 unsigned int offs = 0;
286 unsigned int extra = 0;
287 __le32 packet_length;
288 int i;
289
290 /* For tx_length_quirk, put packet length at start of packet */
291 if (has_tx_length_quirk(ep->chip))
292 extra = sizeof(packet_length);
293
294 for (i = 0; i < ctx->packets; ++i) {
295 unsigned int offset;
296 unsigned int length;
297 int counts;
298
299 counts = snd_usb_endpoint_next_packet_size(ep, ctx, i, 0);
300 length = counts * ep->stride; /* number of silent bytes */
301 offset = offs * ep->stride + extra * i;
302 urb->iso_frame_desc[i].offset = offset;
303 urb->iso_frame_desc[i].length = length + extra;
304 if (extra) {
305 packet_length = cpu_to_le32(length);
306 memcpy(urb->transfer_buffer + offset,
307 &packet_length, sizeof(packet_length));
308 }
309 memset(urb->transfer_buffer + offset + extra,
310 ep->silence_value, length);
311 offs += counts;
312 }
313
314 urb->number_of_packets = ctx->packets;
315 urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
316 ctx->queued = 0;
317}
318
319/*
320 * Prepare a PLAYBACK urb for submission to the bus.
321 */
322static int prepare_outbound_urb(struct snd_usb_endpoint *ep,
323 struct snd_urb_ctx *ctx,
324 bool in_stream_lock)
325{
326 struct urb *urb = ctx->urb;
327 unsigned char *cp = urb->transfer_buffer;
328 struct snd_usb_substream *data_subs;
329
330 urb->dev = ep->chip->dev; /* we need to set this at each time */
331
332 switch (ep->type) {
333 case SND_USB_ENDPOINT_TYPE_DATA:
334 data_subs = READ_ONCE(ep->data_subs);
335 if (data_subs && ep->prepare_data_urb)
336 return ep->prepare_data_urb(data_subs, urb, in_stream_lock);
337 /* no data provider, so send silence */
338 prepare_silent_urb(ep, ctx);
339 break;
340
341 case SND_USB_ENDPOINT_TYPE_SYNC:
342 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
343 /*
344 * fill the length and offset of each urb descriptor.
345 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
346 */
347 urb->iso_frame_desc[0].length = 4;
348 urb->iso_frame_desc[0].offset = 0;
349 cp[0] = ep->freqn;
350 cp[1] = ep->freqn >> 8;
351 cp[2] = ep->freqn >> 16;
352 cp[3] = ep->freqn >> 24;
353 } else {
354 /*
355 * fill the length and offset of each urb descriptor.
356 * the fixed 10.14 frequency is passed through the pipe.
357 */
358 urb->iso_frame_desc[0].length = 3;
359 urb->iso_frame_desc[0].offset = 0;
360 cp[0] = ep->freqn >> 2;
361 cp[1] = ep->freqn >> 10;
362 cp[2] = ep->freqn >> 18;
363 }
364
365 break;
366 }
367 return 0;
368}
369
370/*
371 * Prepare a CAPTURE or SYNC urb for submission to the bus.
372 */
373static int prepare_inbound_urb(struct snd_usb_endpoint *ep,
374 struct snd_urb_ctx *urb_ctx)
375{
376 int i, offs;
377 struct urb *urb = urb_ctx->urb;
378
379 urb->dev = ep->chip->dev; /* we need to set this at each time */
380
381 switch (ep->type) {
382 case SND_USB_ENDPOINT_TYPE_DATA:
383 offs = 0;
384 for (i = 0; i < urb_ctx->packets; i++) {
385 urb->iso_frame_desc[i].offset = offs;
386 urb->iso_frame_desc[i].length = ep->curpacksize;
387 offs += ep->curpacksize;
388 }
389
390 urb->transfer_buffer_length = offs;
391 urb->number_of_packets = urb_ctx->packets;
392 break;
393
394 case SND_USB_ENDPOINT_TYPE_SYNC:
395 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
396 urb->iso_frame_desc[0].offset = 0;
397 break;
398 }
399 return 0;
400}
401
402/* notify an error as XRUN to the assigned PCM data substream */
403static void notify_xrun(struct snd_usb_endpoint *ep)
404{
405 struct snd_usb_substream *data_subs;
406 struct snd_pcm_substream *psubs;
407
408 data_subs = READ_ONCE(ep->data_subs);
409 if (!data_subs)
410 return;
411 psubs = data_subs->pcm_substream;
412 if (psubs && psubs->runtime &&
413 psubs->runtime->state == SNDRV_PCM_STATE_RUNNING)
414 snd_pcm_stop_xrun(psubs);
415}
416
417static struct snd_usb_packet_info *
418next_packet_fifo_enqueue(struct snd_usb_endpoint *ep)
419{
420 struct snd_usb_packet_info *p;
421
422 p = ep->next_packet + (ep->next_packet_head + ep->next_packet_queued) %
423 ARRAY_SIZE(ep->next_packet);
424 ep->next_packet_queued++;
425 return p;
426}
427
428static struct snd_usb_packet_info *
429next_packet_fifo_dequeue(struct snd_usb_endpoint *ep)
430{
431 struct snd_usb_packet_info *p;
432
433 p = ep->next_packet + ep->next_packet_head;
434 ep->next_packet_head++;
435 ep->next_packet_head %= ARRAY_SIZE(ep->next_packet);
436 ep->next_packet_queued--;
437 return p;
438}
439
440static void push_back_to_ready_list(struct snd_usb_endpoint *ep,
441 struct snd_urb_ctx *ctx)
442{
443 unsigned long flags;
444
445 spin_lock_irqsave(&ep->lock, flags);
446 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
447 spin_unlock_irqrestore(&ep->lock, flags);
448}
449
450/*
451 * Send output urbs that have been prepared previously. URBs are dequeued
452 * from ep->ready_playback_urbs and in case there aren't any available
453 * or there are no packets that have been prepared, this function does
454 * nothing.
455 *
456 * The reason why the functionality of sending and preparing URBs is separated
457 * is that host controllers don't guarantee the order in which they return
458 * inbound and outbound packets to their submitters.
459 *
460 * This function is used both for implicit feedback endpoints and in low-
461 * latency playback mode.
462 */
463int snd_usb_queue_pending_output_urbs(struct snd_usb_endpoint *ep,
464 bool in_stream_lock)
465{
466 bool implicit_fb = snd_usb_endpoint_implicit_feedback_sink(ep);
467
468 while (ep_state_running(ep)) {
469
470 unsigned long flags;
471 struct snd_usb_packet_info *packet;
472 struct snd_urb_ctx *ctx = NULL;
473 int err, i;
474
475 spin_lock_irqsave(&ep->lock, flags);
476 if ((!implicit_fb || ep->next_packet_queued > 0) &&
477 !list_empty(&ep->ready_playback_urbs)) {
478 /* take URB out of FIFO */
479 ctx = list_first_entry(&ep->ready_playback_urbs,
480 struct snd_urb_ctx, ready_list);
481 list_del_init(&ctx->ready_list);
482 if (implicit_fb)
483 packet = next_packet_fifo_dequeue(ep);
484 }
485 spin_unlock_irqrestore(&ep->lock, flags);
486
487 if (ctx == NULL)
488 break;
489
490 /* copy over the length information */
491 if (implicit_fb) {
492 for (i = 0; i < packet->packets; i++)
493 ctx->packet_size[i] = packet->packet_size[i];
494 }
495
496 /* call the data handler to fill in playback data */
497 err = prepare_outbound_urb(ep, ctx, in_stream_lock);
498 /* can be stopped during prepare callback */
499 if (unlikely(!ep_state_running(ep)))
500 break;
501 if (err < 0) {
502 /* push back to ready list again for -EAGAIN */
503 if (err == -EAGAIN) {
504 push_back_to_ready_list(ep, ctx);
505 break;
506 }
507
508 if (!in_stream_lock)
509 notify_xrun(ep);
510 return -EPIPE;
511 }
512
513 if (!atomic_read(&ep->chip->shutdown))
514 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
515 else
516 err = -ENODEV;
517 if (err < 0) {
518 if (!atomic_read(&ep->chip->shutdown)) {
519 usb_audio_err(ep->chip,
520 "Unable to submit urb #%d: %d at %s\n",
521 ctx->index, err, __func__);
522 if (!in_stream_lock)
523 notify_xrun(ep);
524 }
525 return -EPIPE;
526 }
527
528 set_bit(ctx->index, &ep->active_mask);
529 atomic_inc(&ep->submitted_urbs);
530 }
531
532 return 0;
533}
534
535/*
536 * complete callback for urbs
537 */
538static void snd_complete_urb(struct urb *urb)
539{
540 struct snd_urb_ctx *ctx = urb->context;
541 struct snd_usb_endpoint *ep = ctx->ep;
542 int err;
543
544 if (unlikely(urb->status == -ENOENT || /* unlinked */
545 urb->status == -ENODEV || /* device removed */
546 urb->status == -ECONNRESET || /* unlinked */
547 urb->status == -ESHUTDOWN)) /* device disabled */
548 goto exit_clear;
549 /* device disconnected */
550 if (unlikely(atomic_read(&ep->chip->shutdown)))
551 goto exit_clear;
552
553 if (unlikely(!ep_state_running(ep)))
554 goto exit_clear;
555
556 if (usb_pipeout(ep->pipe)) {
557 retire_outbound_urb(ep, ctx);
558 /* can be stopped during retire callback */
559 if (unlikely(!ep_state_running(ep)))
560 goto exit_clear;
561
562 /* in low-latency and implicit-feedback modes, push back the
563 * URB to ready list at first, then process as much as possible
564 */
565 if (ep->lowlatency_playback ||
566 snd_usb_endpoint_implicit_feedback_sink(ep)) {
567 push_back_to_ready_list(ep, ctx);
568 clear_bit(ctx->index, &ep->active_mask);
569 snd_usb_queue_pending_output_urbs(ep, false);
570 /* decrement at last, and check xrun */
571 if (atomic_dec_and_test(&ep->submitted_urbs) &&
572 !snd_usb_endpoint_implicit_feedback_sink(ep))
573 notify_xrun(ep);
574 return;
575 }
576
577 /* in non-lowlatency mode, no error handling for prepare */
578 prepare_outbound_urb(ep, ctx, false);
579 /* can be stopped during prepare callback */
580 if (unlikely(!ep_state_running(ep)))
581 goto exit_clear;
582 } else {
583 retire_inbound_urb(ep, ctx);
584 /* can be stopped during retire callback */
585 if (unlikely(!ep_state_running(ep)))
586 goto exit_clear;
587
588 prepare_inbound_urb(ep, ctx);
589 }
590
591 if (!atomic_read(&ep->chip->shutdown))
592 err = usb_submit_urb(urb, GFP_ATOMIC);
593 else
594 err = -ENODEV;
595 if (err == 0)
596 return;
597
598 if (!atomic_read(&ep->chip->shutdown)) {
599 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
600 notify_xrun(ep);
601 }
602
603exit_clear:
604 clear_bit(ctx->index, &ep->active_mask);
605 atomic_dec(&ep->submitted_urbs);
606}
607
608/*
609 * Find or create a refcount object for the given interface
610 *
611 * The objects are released altogether in snd_usb_endpoint_free_all()
612 */
613static struct snd_usb_iface_ref *
614iface_ref_find(struct snd_usb_audio *chip, int iface)
615{
616 struct snd_usb_iface_ref *ip;
617
618 list_for_each_entry(ip, &chip->iface_ref_list, list)
619 if (ip->iface == iface)
620 return ip;
621
622 ip = kzalloc(sizeof(*ip), GFP_KERNEL);
623 if (!ip)
624 return NULL;
625 ip->iface = iface;
626 list_add_tail(&ip->list, &chip->iface_ref_list);
627 return ip;
628}
629
630/* Similarly, a refcount object for clock */
631static struct snd_usb_clock_ref *
632clock_ref_find(struct snd_usb_audio *chip, int clock)
633{
634 struct snd_usb_clock_ref *ref;
635
636 list_for_each_entry(ref, &chip->clock_ref_list, list)
637 if (ref->clock == clock)
638 return ref;
639
640 ref = kzalloc(sizeof(*ref), GFP_KERNEL);
641 if (!ref)
642 return NULL;
643 ref->clock = clock;
644 atomic_set(&ref->locked, 0);
645 list_add_tail(&ref->list, &chip->clock_ref_list);
646 return ref;
647}
648
649/*
650 * Get the existing endpoint object corresponding EP
651 * Returns NULL if not present.
652 */
653struct snd_usb_endpoint *
654snd_usb_get_endpoint(struct snd_usb_audio *chip, int ep_num)
655{
656 struct snd_usb_endpoint *ep;
657
658 list_for_each_entry(ep, &chip->ep_list, list) {
659 if (ep->ep_num == ep_num)
660 return ep;
661 }
662
663 return NULL;
664}
665
666#define ep_type_name(type) \
667 (type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync")
668
669/**
670 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
671 *
672 * @chip: The chip
673 * @ep_num: The number of the endpoint to use
674 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
675 *
676 * If the requested endpoint has not been added to the given chip before,
677 * a new instance is created.
678 *
679 * Returns zero on success or a negative error code.
680 *
681 * New endpoints will be added to chip->ep_list and freed by
682 * calling snd_usb_endpoint_free_all().
683 *
684 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
685 * bNumEndpoints > 1 beforehand.
686 */
687int snd_usb_add_endpoint(struct snd_usb_audio *chip, int ep_num, int type)
688{
689 struct snd_usb_endpoint *ep;
690 bool is_playback;
691
692 ep = snd_usb_get_endpoint(chip, ep_num);
693 if (ep)
694 return 0;
695
696 usb_audio_dbg(chip, "Creating new %s endpoint #%x\n",
697 ep_type_name(type),
698 ep_num);
699 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
700 if (!ep)
701 return -ENOMEM;
702
703 ep->chip = chip;
704 spin_lock_init(&ep->lock);
705 ep->type = type;
706 ep->ep_num = ep_num;
707 INIT_LIST_HEAD(&ep->ready_playback_urbs);
708 atomic_set(&ep->submitted_urbs, 0);
709
710 is_playback = ((ep_num & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT);
711 ep_num &= USB_ENDPOINT_NUMBER_MASK;
712 if (is_playback)
713 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
714 else
715 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
716
717 list_add_tail(&ep->list, &chip->ep_list);
718 return 0;
719}
720
721/* Set up syncinterval and maxsyncsize for a sync EP */
722static void endpoint_set_syncinterval(struct snd_usb_audio *chip,
723 struct snd_usb_endpoint *ep)
724{
725 struct usb_host_interface *alts;
726 struct usb_endpoint_descriptor *desc;
727
728 alts = snd_usb_get_host_interface(chip, ep->iface, ep->altsetting);
729 if (!alts)
730 return;
731
732 desc = get_endpoint(alts, ep->ep_idx);
733 if (desc->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
734 desc->bRefresh >= 1 && desc->bRefresh <= 9)
735 ep->syncinterval = desc->bRefresh;
736 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
737 ep->syncinterval = 1;
738 else if (desc->bInterval >= 1 && desc->bInterval <= 16)
739 ep->syncinterval = desc->bInterval - 1;
740 else
741 ep->syncinterval = 3;
742
743 ep->syncmaxsize = le16_to_cpu(desc->wMaxPacketSize);
744}
745
746static bool endpoint_compatible(struct snd_usb_endpoint *ep,
747 const struct audioformat *fp,
748 const struct snd_pcm_hw_params *params)
749{
750 if (!ep->opened)
751 return false;
752 if (ep->cur_audiofmt != fp)
753 return false;
754 if (ep->cur_rate != params_rate(params) ||
755 ep->cur_format != params_format(params) ||
756 ep->cur_period_frames != params_period_size(params) ||
757 ep->cur_buffer_periods != params_periods(params))
758 return false;
759 return true;
760}
761
762/*
763 * Check whether the given fp and hw params are compatible with the current
764 * setup of the target EP for implicit feedback sync
765 */
766bool snd_usb_endpoint_compatible(struct snd_usb_audio *chip,
767 struct snd_usb_endpoint *ep,
768 const struct audioformat *fp,
769 const struct snd_pcm_hw_params *params)
770{
771 bool ret;
772
773 mutex_lock(&chip->mutex);
774 ret = endpoint_compatible(ep, fp, params);
775 mutex_unlock(&chip->mutex);
776 return ret;
777}
778
779/*
780 * snd_usb_endpoint_open: Open the endpoint
781 *
782 * Called from hw_params to assign the endpoint to the substream.
783 * It's reference-counted, and only the first opener is allowed to set up
784 * arbitrary parameters. The later opener must be compatible with the
785 * former opened parameters.
786 * The endpoint needs to be closed via snd_usb_endpoint_close() later.
787 *
788 * Note that this function doesn't configure the endpoint. The substream
789 * needs to set it up later via snd_usb_endpoint_set_params() and
790 * snd_usb_endpoint_prepare().
791 */
792struct snd_usb_endpoint *
793snd_usb_endpoint_open(struct snd_usb_audio *chip,
794 const struct audioformat *fp,
795 const struct snd_pcm_hw_params *params,
796 bool is_sync_ep,
797 bool fixed_rate)
798{
799 struct snd_usb_endpoint *ep;
800 int ep_num = is_sync_ep ? fp->sync_ep : fp->endpoint;
801
802 mutex_lock(&chip->mutex);
803 ep = snd_usb_get_endpoint(chip, ep_num);
804 if (!ep) {
805 usb_audio_err(chip, "Cannot find EP 0x%x to open\n", ep_num);
806 goto unlock;
807 }
808
809 if (!ep->opened) {
810 if (is_sync_ep) {
811 ep->iface = fp->sync_iface;
812 ep->altsetting = fp->sync_altsetting;
813 ep->ep_idx = fp->sync_ep_idx;
814 } else {
815 ep->iface = fp->iface;
816 ep->altsetting = fp->altsetting;
817 ep->ep_idx = fp->ep_idx;
818 }
819 usb_audio_dbg(chip, "Open EP 0x%x, iface=%d:%d, idx=%d\n",
820 ep_num, ep->iface, ep->altsetting, ep->ep_idx);
821
822 ep->iface_ref = iface_ref_find(chip, ep->iface);
823 if (!ep->iface_ref) {
824 ep = NULL;
825 goto unlock;
826 }
827
828 if (fp->protocol != UAC_VERSION_1) {
829 ep->clock_ref = clock_ref_find(chip, fp->clock);
830 if (!ep->clock_ref) {
831 ep = NULL;
832 goto unlock;
833 }
834 ep->clock_ref->opened++;
835 }
836
837 ep->cur_audiofmt = fp;
838 ep->cur_channels = fp->channels;
839 ep->cur_rate = params_rate(params);
840 ep->cur_format = params_format(params);
841 ep->cur_frame_bytes = snd_pcm_format_physical_width(ep->cur_format) *
842 ep->cur_channels / 8;
843 ep->cur_period_frames = params_period_size(params);
844 ep->cur_period_bytes = ep->cur_period_frames * ep->cur_frame_bytes;
845 ep->cur_buffer_periods = params_periods(params);
846
847 if (ep->type == SND_USB_ENDPOINT_TYPE_SYNC)
848 endpoint_set_syncinterval(chip, ep);
849
850 ep->implicit_fb_sync = fp->implicit_fb;
851 ep->need_setup = true;
852 ep->need_prepare = true;
853 ep->fixed_rate = fixed_rate;
854
855 usb_audio_dbg(chip, " channels=%d, rate=%d, format=%s, period_bytes=%d, periods=%d, implicit_fb=%d\n",
856 ep->cur_channels, ep->cur_rate,
857 snd_pcm_format_name(ep->cur_format),
858 ep->cur_period_bytes, ep->cur_buffer_periods,
859 ep->implicit_fb_sync);
860
861 } else {
862 if (WARN_ON(!ep->iface_ref)) {
863 ep = NULL;
864 goto unlock;
865 }
866
867 if (!endpoint_compatible(ep, fp, params)) {
868 usb_audio_err(chip, "Incompatible EP setup for 0x%x\n",
869 ep_num);
870 ep = NULL;
871 goto unlock;
872 }
873
874 usb_audio_dbg(chip, "Reopened EP 0x%x (count %d)\n",
875 ep_num, ep->opened);
876 }
877
878 if (!ep->iface_ref->opened++)
879 ep->iface_ref->need_setup = true;
880
881 ep->opened++;
882
883 unlock:
884 mutex_unlock(&chip->mutex);
885 return ep;
886}
887
888/*
889 * snd_usb_endpoint_set_sync: Link data and sync endpoints
890 *
891 * Pass NULL to sync_ep to unlink again
892 */
893void snd_usb_endpoint_set_sync(struct snd_usb_audio *chip,
894 struct snd_usb_endpoint *data_ep,
895 struct snd_usb_endpoint *sync_ep)
896{
897 data_ep->sync_source = sync_ep;
898}
899
900/*
901 * Set data endpoint callbacks and the assigned data stream
902 *
903 * Called at PCM trigger and cleanups.
904 * Pass NULL to deactivate each callback.
905 */
906void snd_usb_endpoint_set_callback(struct snd_usb_endpoint *ep,
907 int (*prepare)(struct snd_usb_substream *subs,
908 struct urb *urb,
909 bool in_stream_lock),
910 void (*retire)(struct snd_usb_substream *subs,
911 struct urb *urb),
912 struct snd_usb_substream *data_subs)
913{
914 ep->prepare_data_urb = prepare;
915 ep->retire_data_urb = retire;
916 if (data_subs)
917 ep->lowlatency_playback = data_subs->lowlatency_playback;
918 else
919 ep->lowlatency_playback = false;
920 WRITE_ONCE(ep->data_subs, data_subs);
921}
922
923static int endpoint_set_interface(struct snd_usb_audio *chip,
924 struct snd_usb_endpoint *ep,
925 bool set)
926{
927 int altset = set ? ep->altsetting : 0;
928 int err;
929
930 if (ep->iface_ref->altset == altset)
931 return 0;
932 /* already disconnected? */
933 if (unlikely(atomic_read(&chip->shutdown)))
934 return -ENODEV;
935
936 usb_audio_dbg(chip, "Setting usb interface %d:%d for EP 0x%x\n",
937 ep->iface, altset, ep->ep_num);
938 err = usb_set_interface(chip->dev, ep->iface, altset);
939 if (err < 0) {
940 usb_audio_err_ratelimited(
941 chip, "%d:%d: usb_set_interface failed (%d)\n",
942 ep->iface, altset, err);
943 return err;
944 }
945
946 if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY)
947 msleep(50);
948 ep->iface_ref->altset = altset;
949 return 0;
950}
951
952/*
953 * snd_usb_endpoint_close: Close the endpoint
954 *
955 * Unreference the already opened endpoint via snd_usb_endpoint_open().
956 */
957void snd_usb_endpoint_close(struct snd_usb_audio *chip,
958 struct snd_usb_endpoint *ep)
959{
960 mutex_lock(&chip->mutex);
961 usb_audio_dbg(chip, "Closing EP 0x%x (count %d)\n",
962 ep->ep_num, ep->opened);
963
964 if (!--ep->iface_ref->opened &&
965 !(chip->quirk_flags & QUIRK_FLAG_IFACE_SKIP_CLOSE))
966 endpoint_set_interface(chip, ep, false);
967
968 if (!--ep->opened) {
969 if (ep->clock_ref) {
970 if (!--ep->clock_ref->opened)
971 ep->clock_ref->rate = 0;
972 }
973 ep->iface = 0;
974 ep->altsetting = 0;
975 ep->cur_audiofmt = NULL;
976 ep->cur_rate = 0;
977 ep->iface_ref = NULL;
978 ep->clock_ref = NULL;
979 usb_audio_dbg(chip, "EP 0x%x closed\n", ep->ep_num);
980 }
981 mutex_unlock(&chip->mutex);
982}
983
984/* Prepare for suspening EP, called from the main suspend handler */
985void snd_usb_endpoint_suspend(struct snd_usb_endpoint *ep)
986{
987 ep->need_prepare = true;
988 if (ep->iface_ref)
989 ep->iface_ref->need_setup = true;
990 if (ep->clock_ref)
991 ep->clock_ref->rate = 0;
992}
993
994/*
995 * wait until all urbs are processed.
996 */
997static int wait_clear_urbs(struct snd_usb_endpoint *ep)
998{
999 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
1000 int alive;
1001
1002 if (atomic_read(&ep->state) != EP_STATE_STOPPING)
1003 return 0;
1004
1005 do {
1006 alive = atomic_read(&ep->submitted_urbs);
1007 if (!alive)
1008 break;
1009
1010 schedule_timeout_uninterruptible(1);
1011 } while (time_before(jiffies, end_time));
1012
1013 if (alive)
1014 usb_audio_err(ep->chip,
1015 "timeout: still %d active urbs on EP #%x\n",
1016 alive, ep->ep_num);
1017
1018 if (ep_state_update(ep, EP_STATE_STOPPING, EP_STATE_STOPPED)) {
1019 ep->sync_sink = NULL;
1020 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
1021 }
1022
1023 return 0;
1024}
1025
1026/* sync the pending stop operation;
1027 * this function itself doesn't trigger the stop operation
1028 */
1029void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
1030{
1031 if (ep)
1032 wait_clear_urbs(ep);
1033}
1034
1035/*
1036 * Stop active urbs
1037 *
1038 * This function moves the EP to STOPPING state if it's being RUNNING.
1039 */
1040static int stop_urbs(struct snd_usb_endpoint *ep, bool force, bool keep_pending)
1041{
1042 unsigned int i;
1043 unsigned long flags;
1044
1045 if (!force && atomic_read(&ep->running))
1046 return -EBUSY;
1047
1048 if (!ep_state_update(ep, EP_STATE_RUNNING, EP_STATE_STOPPING))
1049 return 0;
1050
1051 spin_lock_irqsave(&ep->lock, flags);
1052 INIT_LIST_HEAD(&ep->ready_playback_urbs);
1053 ep->next_packet_head = 0;
1054 ep->next_packet_queued = 0;
1055 spin_unlock_irqrestore(&ep->lock, flags);
1056
1057 if (keep_pending)
1058 return 0;
1059
1060 for (i = 0; i < ep->nurbs; i++) {
1061 if (test_bit(i, &ep->active_mask)) {
1062 if (!test_and_set_bit(i, &ep->unlink_mask)) {
1063 struct urb *u = ep->urb[i].urb;
1064 usb_unlink_urb(u);
1065 }
1066 }
1067 }
1068
1069 return 0;
1070}
1071
1072/*
1073 * release an endpoint's urbs
1074 */
1075static int release_urbs(struct snd_usb_endpoint *ep, bool force)
1076{
1077 int i, err;
1078
1079 /* route incoming urbs to nirvana */
1080 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
1081
1082 /* stop and unlink urbs */
1083 err = stop_urbs(ep, force, false);
1084 if (err)
1085 return err;
1086
1087 wait_clear_urbs(ep);
1088
1089 for (i = 0; i < ep->nurbs; i++)
1090 release_urb_ctx(&ep->urb[i]);
1091
1092 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
1093 ep->syncbuf, ep->sync_dma);
1094
1095 ep->syncbuf = NULL;
1096 ep->nurbs = 0;
1097 return 0;
1098}
1099
1100/*
1101 * configure a data endpoint
1102 */
1103static int data_ep_set_params(struct snd_usb_endpoint *ep)
1104{
1105 struct snd_usb_audio *chip = ep->chip;
1106 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
1107 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
1108 unsigned int max_urbs, i;
1109 const struct audioformat *fmt = ep->cur_audiofmt;
1110 int frame_bits = ep->cur_frame_bytes * 8;
1111 int tx_length_quirk = (has_tx_length_quirk(chip) &&
1112 usb_pipeout(ep->pipe));
1113
1114 usb_audio_dbg(chip, "Setting params for data EP 0x%x, pipe 0x%x\n",
1115 ep->ep_num, ep->pipe);
1116
1117 if (ep->cur_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
1118 /*
1119 * When operating in DSD DOP mode, the size of a sample frame
1120 * in hardware differs from the actual physical format width
1121 * because we need to make room for the DOP markers.
1122 */
1123 frame_bits += ep->cur_channels << 3;
1124 }
1125
1126 ep->datainterval = fmt->datainterval;
1127 ep->stride = frame_bits >> 3;
1128
1129 switch (ep->cur_format) {
1130 case SNDRV_PCM_FORMAT_U8:
1131 ep->silence_value = 0x80;
1132 break;
1133 case SNDRV_PCM_FORMAT_DSD_U8:
1134 case SNDRV_PCM_FORMAT_DSD_U16_LE:
1135 case SNDRV_PCM_FORMAT_DSD_U32_LE:
1136 case SNDRV_PCM_FORMAT_DSD_U16_BE:
1137 case SNDRV_PCM_FORMAT_DSD_U32_BE:
1138 ep->silence_value = 0x69;
1139 break;
1140 default:
1141 ep->silence_value = 0;
1142 }
1143
1144 /* assume max. frequency is 50% higher than nominal */
1145 ep->freqmax = ep->freqn + (ep->freqn >> 1);
1146 /* Round up freqmax to nearest integer in order to calculate maximum
1147 * packet size, which must represent a whole number of frames.
1148 * This is accomplished by adding 0x0.ffff before converting the
1149 * Q16.16 format into integer.
1150 * In order to accurately calculate the maximum packet size when
1151 * the data interval is more than 1 (i.e. ep->datainterval > 0),
1152 * multiply by the data interval prior to rounding. For instance,
1153 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
1154 * frames with a data interval of 1, but 11 (10.25) frames with a
1155 * data interval of 2.
1156 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
1157 * maximum datainterval value of 3, at USB full speed, higher for
1158 * USB high speed, noting that ep->freqmax is in units of
1159 * frames per packet in Q16.16 format.)
1160 */
1161 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
1162 (frame_bits >> 3);
1163 if (tx_length_quirk)
1164 maxsize += sizeof(__le32); /* Space for length descriptor */
1165 /* but wMaxPacketSize might reduce this */
1166 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
1167 /* whatever fits into a max. size packet */
1168 unsigned int data_maxsize = maxsize = ep->maxpacksize;
1169
1170 if (tx_length_quirk)
1171 /* Need to remove the length descriptor to calc freq */
1172 data_maxsize -= sizeof(__le32);
1173 ep->freqmax = (data_maxsize / (frame_bits >> 3))
1174 << (16 - ep->datainterval);
1175 }
1176
1177 if (ep->fill_max)
1178 ep->curpacksize = ep->maxpacksize;
1179 else
1180 ep->curpacksize = maxsize;
1181
1182 if (snd_usb_get_speed(chip->dev) != USB_SPEED_FULL) {
1183 packs_per_ms = 8 >> ep->datainterval;
1184 max_packs_per_urb = MAX_PACKS_HS;
1185 } else {
1186 packs_per_ms = 1;
1187 max_packs_per_urb = MAX_PACKS;
1188 }
1189 if (ep->sync_source && !ep->implicit_fb_sync)
1190 max_packs_per_urb = min(max_packs_per_urb,
1191 1U << ep->sync_source->syncinterval);
1192 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
1193
1194 /*
1195 * Capture endpoints need to use small URBs because there's no way
1196 * to tell in advance where the next period will end, and we don't
1197 * want the next URB to complete much after the period ends.
1198 *
1199 * Playback endpoints with implicit sync much use the same parameters
1200 * as their corresponding capture endpoint.
1201 */
1202 if (usb_pipein(ep->pipe) || ep->implicit_fb_sync) {
1203
1204 /* make capture URBs <= 1 ms and smaller than a period */
1205 urb_packs = min(max_packs_per_urb, packs_per_ms);
1206 while (urb_packs > 1 && urb_packs * maxsize >= ep->cur_period_bytes)
1207 urb_packs >>= 1;
1208 ep->nurbs = MAX_URBS;
1209
1210 /*
1211 * Playback endpoints without implicit sync are adjusted so that
1212 * a period fits as evenly as possible in the smallest number of
1213 * URBs. The total number of URBs is adjusted to the size of the
1214 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
1215 */
1216 } else {
1217 /* determine how small a packet can be */
1218 minsize = (ep->freqn >> (16 - ep->datainterval)) *
1219 (frame_bits >> 3);
1220 /* with sync from device, assume it can be 12% lower */
1221 if (ep->sync_source)
1222 minsize -= minsize >> 3;
1223 minsize = max(minsize, 1u);
1224
1225 /* how many packets will contain an entire ALSA period? */
1226 max_packs_per_period = DIV_ROUND_UP(ep->cur_period_bytes, minsize);
1227
1228 /* how many URBs will contain a period? */
1229 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
1230 max_packs_per_urb);
1231 /* how many packets are needed in each URB? */
1232 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
1233
1234 /* limit the number of frames in a single URB */
1235 ep->max_urb_frames = DIV_ROUND_UP(ep->cur_period_frames,
1236 urbs_per_period);
1237
1238 /* try to use enough URBs to contain an entire ALSA buffer */
1239 max_urbs = min((unsigned) MAX_URBS,
1240 MAX_QUEUE * packs_per_ms / urb_packs);
1241 ep->nurbs = min(max_urbs, urbs_per_period * ep->cur_buffer_periods);
1242 }
1243
1244 /* allocate and initialize data urbs */
1245 for (i = 0; i < ep->nurbs; i++) {
1246 struct snd_urb_ctx *u = &ep->urb[i];
1247 u->index = i;
1248 u->ep = ep;
1249 u->packets = urb_packs;
1250 u->buffer_size = maxsize * u->packets;
1251
1252 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
1253 u->packets++; /* for transfer delimiter */
1254 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
1255 if (!u->urb)
1256 goto out_of_memory;
1257
1258 u->urb->transfer_buffer =
1259 usb_alloc_coherent(chip->dev, u->buffer_size,
1260 GFP_KERNEL, &u->urb->transfer_dma);
1261 if (!u->urb->transfer_buffer)
1262 goto out_of_memory;
1263 u->urb->pipe = ep->pipe;
1264 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1265 u->urb->interval = 1 << ep->datainterval;
1266 u->urb->context = u;
1267 u->urb->complete = snd_complete_urb;
1268 INIT_LIST_HEAD(&u->ready_list);
1269 }
1270
1271 return 0;
1272
1273out_of_memory:
1274 release_urbs(ep, false);
1275 return -ENOMEM;
1276}
1277
1278/*
1279 * configure a sync endpoint
1280 */
1281static int sync_ep_set_params(struct snd_usb_endpoint *ep)
1282{
1283 struct snd_usb_audio *chip = ep->chip;
1284 int i;
1285
1286 usb_audio_dbg(chip, "Setting params for sync EP 0x%x, pipe 0x%x\n",
1287 ep->ep_num, ep->pipe);
1288
1289 ep->syncbuf = usb_alloc_coherent(chip->dev, SYNC_URBS * 4,
1290 GFP_KERNEL, &ep->sync_dma);
1291 if (!ep->syncbuf)
1292 return -ENOMEM;
1293
1294 ep->nurbs = SYNC_URBS;
1295 for (i = 0; i < SYNC_URBS; i++) {
1296 struct snd_urb_ctx *u = &ep->urb[i];
1297 u->index = i;
1298 u->ep = ep;
1299 u->packets = 1;
1300 u->urb = usb_alloc_urb(1, GFP_KERNEL);
1301 if (!u->urb)
1302 goto out_of_memory;
1303 u->urb->transfer_buffer = ep->syncbuf + i * 4;
1304 u->urb->transfer_dma = ep->sync_dma + i * 4;
1305 u->urb->transfer_buffer_length = 4;
1306 u->urb->pipe = ep->pipe;
1307 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1308 u->urb->number_of_packets = 1;
1309 u->urb->interval = 1 << ep->syncinterval;
1310 u->urb->context = u;
1311 u->urb->complete = snd_complete_urb;
1312 }
1313
1314 return 0;
1315
1316out_of_memory:
1317 release_urbs(ep, false);
1318 return -ENOMEM;
1319}
1320
1321/* update the rate of the referred clock; return the actual rate */
1322static int update_clock_ref_rate(struct snd_usb_audio *chip,
1323 struct snd_usb_endpoint *ep)
1324{
1325 struct snd_usb_clock_ref *clock = ep->clock_ref;
1326 int rate = ep->cur_rate;
1327
1328 if (!clock || clock->rate == rate)
1329 return rate;
1330 if (clock->rate) {
1331 if (atomic_read(&clock->locked))
1332 return clock->rate;
1333 if (clock->rate != rate) {
1334 usb_audio_err(chip, "Mismatched sample rate %d vs %d for EP 0x%x\n",
1335 clock->rate, rate, ep->ep_num);
1336 return clock->rate;
1337 }
1338 }
1339 clock->rate = rate;
1340 clock->need_setup = true;
1341 return rate;
1342}
1343
1344/*
1345 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
1346 *
1347 * It's called either from hw_params callback.
1348 * Determine the number of URBs to be used on this endpoint.
1349 * An endpoint must be configured before it can be started.
1350 * An endpoint that is already running can not be reconfigured.
1351 */
1352int snd_usb_endpoint_set_params(struct snd_usb_audio *chip,
1353 struct snd_usb_endpoint *ep)
1354{
1355 const struct audioformat *fmt = ep->cur_audiofmt;
1356 int err = 0;
1357
1358 mutex_lock(&chip->mutex);
1359 if (!ep->need_setup)
1360 goto unlock;
1361
1362 /* release old buffers, if any */
1363 err = release_urbs(ep, false);
1364 if (err < 0)
1365 goto unlock;
1366
1367 ep->datainterval = fmt->datainterval;
1368 ep->maxpacksize = fmt->maxpacksize;
1369 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
1370
1371 if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) {
1372 ep->freqn = get_usb_full_speed_rate(ep->cur_rate);
1373 ep->pps = 1000 >> ep->datainterval;
1374 } else {
1375 ep->freqn = get_usb_high_speed_rate(ep->cur_rate);
1376 ep->pps = 8000 >> ep->datainterval;
1377 }
1378
1379 ep->sample_rem = ep->cur_rate % ep->pps;
1380 ep->packsize[0] = ep->cur_rate / ep->pps;
1381 ep->packsize[1] = (ep->cur_rate + (ep->pps - 1)) / ep->pps;
1382
1383 /* calculate the frequency in 16.16 format */
1384 ep->freqm = ep->freqn;
1385 ep->freqshift = INT_MIN;
1386
1387 ep->phase = 0;
1388
1389 switch (ep->type) {
1390 case SND_USB_ENDPOINT_TYPE_DATA:
1391 err = data_ep_set_params(ep);
1392 break;
1393 case SND_USB_ENDPOINT_TYPE_SYNC:
1394 err = sync_ep_set_params(ep);
1395 break;
1396 default:
1397 err = -EINVAL;
1398 }
1399
1400 usb_audio_dbg(chip, "Set up %d URBS, ret=%d\n", ep->nurbs, err);
1401
1402 if (err < 0)
1403 goto unlock;
1404
1405 /* some unit conversions in runtime */
1406 ep->maxframesize = ep->maxpacksize / ep->cur_frame_bytes;
1407 ep->curframesize = ep->curpacksize / ep->cur_frame_bytes;
1408
1409 err = update_clock_ref_rate(chip, ep);
1410 if (err >= 0) {
1411 ep->need_setup = false;
1412 err = 0;
1413 }
1414
1415 unlock:
1416 mutex_unlock(&chip->mutex);
1417 return err;
1418}
1419
1420static int init_sample_rate(struct snd_usb_audio *chip,
1421 struct snd_usb_endpoint *ep)
1422{
1423 struct snd_usb_clock_ref *clock = ep->clock_ref;
1424 int rate, err;
1425
1426 rate = update_clock_ref_rate(chip, ep);
1427 if (rate < 0)
1428 return rate;
1429 if (clock && !clock->need_setup)
1430 return 0;
1431
1432 if (!ep->fixed_rate) {
1433 err = snd_usb_init_sample_rate(chip, ep->cur_audiofmt, rate);
1434 if (err < 0) {
1435 if (clock)
1436 clock->rate = 0; /* reset rate */
1437 return err;
1438 }
1439 }
1440
1441 if (clock)
1442 clock->need_setup = false;
1443 return 0;
1444}
1445
1446/*
1447 * snd_usb_endpoint_prepare: Prepare the endpoint
1448 *
1449 * This function sets up the EP to be fully usable state.
1450 * It's called either from prepare callback.
1451 * The function checks need_setup flag, and performs nothing unless needed,
1452 * so it's safe to call this multiple times.
1453 *
1454 * This returns zero if unchanged, 1 if the configuration has changed,
1455 * or a negative error code.
1456 */
1457int snd_usb_endpoint_prepare(struct snd_usb_audio *chip,
1458 struct snd_usb_endpoint *ep)
1459{
1460 bool iface_first;
1461 int err = 0;
1462
1463 mutex_lock(&chip->mutex);
1464 if (WARN_ON(!ep->iface_ref))
1465 goto unlock;
1466 if (!ep->need_prepare)
1467 goto unlock;
1468
1469 /* If the interface has been already set up, just set EP parameters */
1470 if (!ep->iface_ref->need_setup) {
1471 /* sample rate setup of UAC1 is per endpoint, and we need
1472 * to update at each EP configuration
1473 */
1474 if (ep->cur_audiofmt->protocol == UAC_VERSION_1) {
1475 err = init_sample_rate(chip, ep);
1476 if (err < 0)
1477 goto unlock;
1478 }
1479 goto done;
1480 }
1481
1482 /* Need to deselect altsetting at first */
1483 endpoint_set_interface(chip, ep, false);
1484
1485 /* Some UAC1 devices (e.g. Yamaha THR10) need the host interface
1486 * to be set up before parameter setups
1487 */
1488 iface_first = ep->cur_audiofmt->protocol == UAC_VERSION_1;
1489 /* Workaround for devices that require the interface setup at first like UAC1 */
1490 if (chip->quirk_flags & QUIRK_FLAG_SET_IFACE_FIRST)
1491 iface_first = true;
1492 if (iface_first) {
1493 err = endpoint_set_interface(chip, ep, true);
1494 if (err < 0)
1495 goto unlock;
1496 }
1497
1498 err = snd_usb_init_pitch(chip, ep->cur_audiofmt);
1499 if (err < 0)
1500 goto unlock;
1501
1502 err = init_sample_rate(chip, ep);
1503 if (err < 0)
1504 goto unlock;
1505
1506 err = snd_usb_select_mode_quirk(chip, ep->cur_audiofmt);
1507 if (err < 0)
1508 goto unlock;
1509
1510 /* for UAC2/3, enable the interface altset here at last */
1511 if (!iface_first) {
1512 err = endpoint_set_interface(chip, ep, true);
1513 if (err < 0)
1514 goto unlock;
1515 }
1516
1517 ep->iface_ref->need_setup = false;
1518
1519 done:
1520 ep->need_prepare = false;
1521 err = 1;
1522
1523unlock:
1524 mutex_unlock(&chip->mutex);
1525 return err;
1526}
1527
1528/* get the current rate set to the given clock by any endpoint */
1529int snd_usb_endpoint_get_clock_rate(struct snd_usb_audio *chip, int clock)
1530{
1531 struct snd_usb_clock_ref *ref;
1532 int rate = 0;
1533
1534 if (!clock)
1535 return 0;
1536 mutex_lock(&chip->mutex);
1537 list_for_each_entry(ref, &chip->clock_ref_list, list) {
1538 if (ref->clock == clock) {
1539 rate = ref->rate;
1540 break;
1541 }
1542 }
1543 mutex_unlock(&chip->mutex);
1544 return rate;
1545}
1546
1547/**
1548 * snd_usb_endpoint_start: start an snd_usb_endpoint
1549 *
1550 * @ep: the endpoint to start
1551 *
1552 * A call to this function will increment the running count of the endpoint.
1553 * In case it is not already running, the URBs for this endpoint will be
1554 * submitted. Otherwise, this function does nothing.
1555 *
1556 * Must be balanced to calls of snd_usb_endpoint_stop().
1557 *
1558 * Returns an error if the URB submission failed, 0 in all other cases.
1559 */
1560int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
1561{
1562 bool is_playback = usb_pipeout(ep->pipe);
1563 int err;
1564 unsigned int i;
1565
1566 if (atomic_read(&ep->chip->shutdown))
1567 return -EBADFD;
1568
1569 if (ep->sync_source)
1570 WRITE_ONCE(ep->sync_source->sync_sink, ep);
1571
1572 usb_audio_dbg(ep->chip, "Starting %s EP 0x%x (running %d)\n",
1573 ep_type_name(ep->type), ep->ep_num,
1574 atomic_read(&ep->running));
1575
1576 /* already running? */
1577 if (atomic_inc_return(&ep->running) != 1)
1578 return 0;
1579
1580 if (ep->clock_ref)
1581 atomic_inc(&ep->clock_ref->locked);
1582
1583 ep->active_mask = 0;
1584 ep->unlink_mask = 0;
1585 ep->phase = 0;
1586 ep->sample_accum = 0;
1587
1588 snd_usb_endpoint_start_quirk(ep);
1589
1590 /*
1591 * If this endpoint has a data endpoint as implicit feedback source,
1592 * don't start the urbs here. Instead, mark them all as available,
1593 * wait for the record urbs to return and queue the playback urbs
1594 * from that context.
1595 */
1596
1597 if (!ep_state_update(ep, EP_STATE_STOPPED, EP_STATE_RUNNING))
1598 goto __error;
1599
1600 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1601 !(ep->chip->quirk_flags & QUIRK_FLAG_PLAYBACK_FIRST)) {
1602 usb_audio_dbg(ep->chip, "No URB submission due to implicit fb sync\n");
1603 i = 0;
1604 goto fill_rest;
1605 }
1606
1607 for (i = 0; i < ep->nurbs; i++) {
1608 struct urb *urb = ep->urb[i].urb;
1609
1610 if (snd_BUG_ON(!urb))
1611 goto __error;
1612
1613 if (is_playback)
1614 err = prepare_outbound_urb(ep, urb->context, true);
1615 else
1616 err = prepare_inbound_urb(ep, urb->context);
1617 if (err < 0) {
1618 /* stop filling at applptr */
1619 if (err == -EAGAIN)
1620 break;
1621 usb_audio_dbg(ep->chip,
1622 "EP 0x%x: failed to prepare urb: %d\n",
1623 ep->ep_num, err);
1624 goto __error;
1625 }
1626
1627 if (!atomic_read(&ep->chip->shutdown))
1628 err = usb_submit_urb(urb, GFP_ATOMIC);
1629 else
1630 err = -ENODEV;
1631 if (err < 0) {
1632 if (!atomic_read(&ep->chip->shutdown))
1633 usb_audio_err(ep->chip,
1634 "cannot submit urb %d, error %d: %s\n",
1635 i, err, usb_error_string(err));
1636 goto __error;
1637 }
1638 set_bit(i, &ep->active_mask);
1639 atomic_inc(&ep->submitted_urbs);
1640 }
1641
1642 if (!i) {
1643 usb_audio_dbg(ep->chip, "XRUN at starting EP 0x%x\n",
1644 ep->ep_num);
1645 goto __error;
1646 }
1647
1648 usb_audio_dbg(ep->chip, "%d URBs submitted for EP 0x%x\n",
1649 i, ep->ep_num);
1650
1651 fill_rest:
1652 /* put the remaining URBs to ready list */
1653 if (is_playback) {
1654 for (; i < ep->nurbs; i++)
1655 push_back_to_ready_list(ep, ep->urb + i);
1656 }
1657
1658 return 0;
1659
1660__error:
1661 snd_usb_endpoint_stop(ep, false);
1662 return -EPIPE;
1663}
1664
1665/**
1666 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
1667 *
1668 * @ep: the endpoint to stop (may be NULL)
1669 * @keep_pending: keep in-flight URBs
1670 *
1671 * A call to this function will decrement the running count of the endpoint.
1672 * In case the last user has requested the endpoint stop, the URBs will
1673 * actually be deactivated.
1674 *
1675 * Must be balanced to calls of snd_usb_endpoint_start().
1676 *
1677 * The caller needs to synchronize the pending stop operation via
1678 * snd_usb_endpoint_sync_pending_stop().
1679 */
1680void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep, bool keep_pending)
1681{
1682 if (!ep)
1683 return;
1684
1685 usb_audio_dbg(ep->chip, "Stopping %s EP 0x%x (running %d)\n",
1686 ep_type_name(ep->type), ep->ep_num,
1687 atomic_read(&ep->running));
1688
1689 if (snd_BUG_ON(!atomic_read(&ep->running)))
1690 return;
1691
1692 if (!atomic_dec_return(&ep->running)) {
1693 if (ep->sync_source)
1694 WRITE_ONCE(ep->sync_source->sync_sink, NULL);
1695 stop_urbs(ep, false, keep_pending);
1696 if (ep->clock_ref)
1697 atomic_dec(&ep->clock_ref->locked);
1698
1699 if (ep->chip->quirk_flags & QUIRK_FLAG_FORCE_IFACE_RESET &&
1700 usb_pipeout(ep->pipe)) {
1701 ep->need_prepare = true;
1702 if (ep->iface_ref)
1703 ep->iface_ref->need_setup = true;
1704 }
1705 }
1706}
1707
1708/**
1709 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1710 *
1711 * @ep: the endpoint to release
1712 *
1713 * This function does not care for the endpoint's running count but will tear
1714 * down all the streaming URBs immediately.
1715 */
1716void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1717{
1718 release_urbs(ep, true);
1719}
1720
1721/**
1722 * snd_usb_endpoint_free_all: Free the resources of an snd_usb_endpoint
1723 * @chip: The chip
1724 *
1725 * This free all endpoints and those resources
1726 */
1727void snd_usb_endpoint_free_all(struct snd_usb_audio *chip)
1728{
1729 struct snd_usb_endpoint *ep, *en;
1730 struct snd_usb_iface_ref *ip, *in;
1731 struct snd_usb_clock_ref *cp, *cn;
1732
1733 list_for_each_entry_safe(ep, en, &chip->ep_list, list)
1734 kfree(ep);
1735
1736 list_for_each_entry_safe(ip, in, &chip->iface_ref_list, list)
1737 kfree(ip);
1738
1739 list_for_each_entry_safe(cp, cn, &chip->clock_ref_list, list)
1740 kfree(cp);
1741}
1742
1743/*
1744 * snd_usb_handle_sync_urb: parse an USB sync packet
1745 *
1746 * @ep: the endpoint to handle the packet
1747 * @sender: the sending endpoint
1748 * @urb: the received packet
1749 *
1750 * This function is called from the context of an endpoint that received
1751 * the packet and is used to let another endpoint object handle the payload.
1752 */
1753static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1754 struct snd_usb_endpoint *sender,
1755 const struct urb *urb)
1756{
1757 int shift;
1758 unsigned int f;
1759 unsigned long flags;
1760
1761 snd_BUG_ON(ep == sender);
1762
1763 /*
1764 * In case the endpoint is operating in implicit feedback mode, prepare
1765 * a new outbound URB that has the same layout as the received packet
1766 * and add it to the list of pending urbs. queue_pending_output_urbs()
1767 * will take care of them later.
1768 */
1769 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1770 atomic_read(&ep->running)) {
1771
1772 /* implicit feedback case */
1773 int i, bytes = 0;
1774 struct snd_urb_ctx *in_ctx;
1775 struct snd_usb_packet_info *out_packet;
1776
1777 in_ctx = urb->context;
1778
1779 /* Count overall packet size */
1780 for (i = 0; i < in_ctx->packets; i++)
1781 if (urb->iso_frame_desc[i].status == 0)
1782 bytes += urb->iso_frame_desc[i].actual_length;
1783
1784 /*
1785 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1786 * streaming once it received a 0-byte OUT URB
1787 */
1788 if (bytes == 0)
1789 return;
1790
1791 spin_lock_irqsave(&ep->lock, flags);
1792 if (ep->next_packet_queued >= ARRAY_SIZE(ep->next_packet)) {
1793 spin_unlock_irqrestore(&ep->lock, flags);
1794 usb_audio_err(ep->chip,
1795 "next package FIFO overflow EP 0x%x\n",
1796 ep->ep_num);
1797 notify_xrun(ep);
1798 return;
1799 }
1800
1801 out_packet = next_packet_fifo_enqueue(ep);
1802
1803 /*
1804 * Iterate through the inbound packet and prepare the lengths
1805 * for the output packet. The OUT packet we are about to send
1806 * will have the same amount of payload bytes per stride as the
1807 * IN packet we just received. Since the actual size is scaled
1808 * by the stride, use the sender stride to calculate the length
1809 * in case the number of channels differ between the implicitly
1810 * fed-back endpoint and the synchronizing endpoint.
1811 */
1812
1813 out_packet->packets = in_ctx->packets;
1814 for (i = 0; i < in_ctx->packets; i++) {
1815 if (urb->iso_frame_desc[i].status == 0)
1816 out_packet->packet_size[i] =
1817 urb->iso_frame_desc[i].actual_length / sender->stride;
1818 else
1819 out_packet->packet_size[i] = 0;
1820 }
1821
1822 spin_unlock_irqrestore(&ep->lock, flags);
1823 snd_usb_queue_pending_output_urbs(ep, false);
1824
1825 return;
1826 }
1827
1828 /*
1829 * process after playback sync complete
1830 *
1831 * Full speed devices report feedback values in 10.14 format as samples
1832 * per frame, high speed devices in 16.16 format as samples per
1833 * microframe.
1834 *
1835 * Because the Audio Class 1 spec was written before USB 2.0, many high
1836 * speed devices use a wrong interpretation, some others use an
1837 * entirely different format.
1838 *
1839 * Therefore, we cannot predict what format any particular device uses
1840 * and must detect it automatically.
1841 */
1842
1843 if (urb->iso_frame_desc[0].status != 0 ||
1844 urb->iso_frame_desc[0].actual_length < 3)
1845 return;
1846
1847 f = le32_to_cpup(urb->transfer_buffer);
1848 if (urb->iso_frame_desc[0].actual_length == 3)
1849 f &= 0x00ffffff;
1850 else
1851 f &= 0x0fffffff;
1852
1853 if (f == 0)
1854 return;
1855
1856 if (unlikely(sender->tenor_fb_quirk)) {
1857 /*
1858 * Devices based on Tenor 8802 chipsets (TEAC UD-H01
1859 * and others) sometimes change the feedback value
1860 * by +/- 0x1.0000.
1861 */
1862 if (f < ep->freqn - 0x8000)
1863 f += 0xf000;
1864 else if (f > ep->freqn + 0x8000)
1865 f -= 0xf000;
1866 } else if (unlikely(ep->freqshift == INT_MIN)) {
1867 /*
1868 * The first time we see a feedback value, determine its format
1869 * by shifting it left or right until it matches the nominal
1870 * frequency value. This assumes that the feedback does not
1871 * differ from the nominal value more than +50% or -25%.
1872 */
1873 shift = 0;
1874 while (f < ep->freqn - ep->freqn / 4) {
1875 f <<= 1;
1876 shift++;
1877 }
1878 while (f > ep->freqn + ep->freqn / 2) {
1879 f >>= 1;
1880 shift--;
1881 }
1882 ep->freqshift = shift;
1883 } else if (ep->freqshift >= 0)
1884 f <<= ep->freqshift;
1885 else
1886 f >>= -ep->freqshift;
1887
1888 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1889 /*
1890 * If the frequency looks valid, set it.
1891 * This value is referred to in prepare_playback_urb().
1892 */
1893 spin_lock_irqsave(&ep->lock, flags);
1894 ep->freqm = f;
1895 spin_unlock_irqrestore(&ep->lock, flags);
1896 } else {
1897 /*
1898 * Out of range; maybe the shift value is wrong.
1899 * Reset it so that we autodetect again the next time.
1900 */
1901 ep->freqshift = INT_MIN;
1902 }
1903}
1904