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