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Merge tag 'mm-hotfixes-stable-2025-07-11-16-16' of git://git.kernel.org/pub/scm/linux...
[linux-block.git] / sound / usb / endpoint.c
... / ...
CommitLineData
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 */
4
5#include <linux/gfp.h>
6#include <linux/init.h>
7#include <linux/ratelimit.h>
8#include <linux/usb.h>
9#include <linux/usb/audio.h>
10#include <linux/slab.h>
11
12#include <sound/core.h>
13#include <sound/pcm.h>
14#include <sound/pcm_params.h>
15
16#include "usbaudio.h"
17#include "helper.h"
18#include "card.h"
19#include "endpoint.h"
20#include "pcm.h"
21#include "clock.h"
22#include "quirks.h"
23
24enum {
25 EP_STATE_STOPPED,
26 EP_STATE_RUNNING,
27 EP_STATE_STOPPING,
28};
29
30/* interface refcounting */
31struct snd_usb_iface_ref {
32 unsigned char iface;
33 bool need_setup;
34 int opened;
35 int altset;
36 struct list_head list;
37};
38
39/* clock refcounting */
40struct snd_usb_clock_ref {
41 unsigned char clock;
42 atomic_t locked;
43 int opened;
44 int rate;
45 bool need_setup;
46 struct list_head list;
47};
48
49/*
50 * snd_usb_endpoint is a model that abstracts everything related to an
51 * USB endpoint and its streaming.
52 *
53 * There are functions to activate and deactivate the streaming URBs and
54 * optional callbacks to let the pcm logic handle the actual content of the
55 * packets for playback and record. Thus, the bus streaming and the audio
56 * handlers are fully decoupled.
57 *
58 * There are two different types of endpoints in audio applications.
59 *
60 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
61 * inbound and outbound traffic.
62 *
63 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
64 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
65 * (3 or 4 bytes).
66 *
67 * Each endpoint has to be configured prior to being used by calling
68 * snd_usb_endpoint_set_params().
69 *
70 * The model incorporates a reference counting, so that multiple users
71 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
72 * only the first user will effectively start the URBs, and only the last
73 * one to stop it will tear the URBs down again.
74 */
75
76/*
77 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
78 * this will overflow at approx 524 kHz
79 */
80static inline unsigned get_usb_full_speed_rate(unsigned int rate)
81{
82 return ((rate << 13) + 62) / 125;
83}
84
85/*
86 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
87 * this will overflow at approx 4 MHz
88 */
89static inline unsigned get_usb_high_speed_rate(unsigned int rate)
90{
91 return ((rate << 10) + 62) / 125;
92}
93
94/*
95 * release a urb data
96 */
97static void release_urb_ctx(struct snd_urb_ctx *u)
98{
99 if (u->urb && u->buffer_size)
100 usb_free_coherent(u->ep->chip->dev, u->buffer_size,
101 u->urb->transfer_buffer,
102 u->urb->transfer_dma);
103 usb_free_urb(u->urb);
104 u->urb = NULL;
105 u->buffer_size = 0;
106}
107
108static const char *usb_error_string(int err)
109{
110 switch (err) {
111 case -ENODEV:
112 return "no device";
113 case -ENOENT:
114 return "endpoint not enabled";
115 case -EPIPE:
116 return "endpoint stalled";
117 case -ENOSPC:
118 return "not enough bandwidth";
119 case -ESHUTDOWN:
120 return "device disabled";
121 case -EHOSTUNREACH:
122 return "device suspended";
123 case -EINVAL:
124 case -EAGAIN:
125 case -EFBIG:
126 case -EMSGSIZE:
127 return "internal error";
128 default:
129 return "unknown error";
130 }
131}
132
133static inline bool ep_state_running(struct snd_usb_endpoint *ep)
134{
135 return atomic_read(&ep->state) == EP_STATE_RUNNING;
136}
137
138static inline bool ep_state_update(struct snd_usb_endpoint *ep, int old, int new)
139{
140 return atomic_try_cmpxchg(&ep->state, &old, new);
141}
142
143/**
144 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
145 *
146 * @ep: The snd_usb_endpoint
147 *
148 * Determine whether an endpoint is driven by an implicit feedback
149 * data endpoint source.
150 */
151int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
152{
153 return ep->implicit_fb_sync && usb_pipeout(ep->pipe);
154}
155
156/*
157 * Return the number of samples to be sent in the next packet
158 * for streaming based on information derived from sync endpoints
159 *
160 * This won't be used for implicit feedback which takes the packet size
161 * returned from the sync source
162 */
163static int slave_next_packet_size(struct snd_usb_endpoint *ep,
164 unsigned int avail)
165{
166 unsigned long flags;
167 unsigned int phase;
168 int ret;
169
170 if (ep->fill_max)
171 return ep->maxframesize;
172
173 spin_lock_irqsave(&ep->lock, flags);
174 phase = (ep->phase & 0xffff) + (ep->freqm << ep->datainterval);
175 ret = min(phase >> 16, ep->maxframesize);
176 if (avail && ret >= avail)
177 ret = -EAGAIN;
178 else
179 ep->phase = phase;
180 spin_unlock_irqrestore(&ep->lock, flags);
181
182 return ret;
183}
184
185/*
186 * Return the number of samples to be sent in the next packet
187 * for adaptive and synchronous endpoints
188 */
189static int next_packet_size(struct snd_usb_endpoint *ep, unsigned int avail)
190{
191 unsigned int sample_accum;
192 int ret;
193
194 if (ep->fill_max)
195 return ep->maxframesize;
196
197 sample_accum = ep->sample_accum + ep->sample_rem;
198 if (sample_accum >= ep->pps) {
199 sample_accum -= ep->pps;
200 ret = ep->packsize[1];
201 } else {
202 ret = ep->packsize[0];
203 }
204 if (avail && ret >= avail)
205 ret = -EAGAIN;
206 else
207 ep->sample_accum = sample_accum;
208
209 return ret;
210}
211
212/*
213 * snd_usb_endpoint_next_packet_size: Return the number of samples to be sent
214 * in the next packet
215 *
216 * If the size is equal or exceeds @avail, don't proceed but return -EAGAIN
217 * Exception: @avail = 0 for skipping the check.
218 */
219int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep,
220 struct snd_urb_ctx *ctx, int idx,
221 unsigned int avail)
222{
223 unsigned int packet;
224
225 packet = ctx->packet_size[idx];
226 if (packet) {
227 if (avail && packet >= avail)
228 return -EAGAIN;
229 return packet;
230 }
231
232 if (ep->sync_source)
233 return slave_next_packet_size(ep, avail);
234 else
235 return next_packet_size(ep, avail);
236}
237
238static void call_retire_callback(struct snd_usb_endpoint *ep,
239 struct urb *urb)
240{
241 struct snd_usb_substream *data_subs;
242
243 data_subs = READ_ONCE(ep->data_subs);
244 if (data_subs && ep->retire_data_urb)
245 ep->retire_data_urb(data_subs, urb);
246}
247
248static void retire_outbound_urb(struct snd_usb_endpoint *ep,
249 struct snd_urb_ctx *urb_ctx)
250{
251 call_retire_callback(ep, urb_ctx->urb);
252}
253
254static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
255 struct snd_usb_endpoint *sender,
256 const struct urb *urb);
257
258static void retire_inbound_urb(struct snd_usb_endpoint *ep,
259 struct snd_urb_ctx *urb_ctx)
260{
261 struct urb *urb = urb_ctx->urb;
262 struct snd_usb_endpoint *sync_sink;
263
264 if (unlikely(ep->skip_packets > 0)) {
265 ep->skip_packets--;
266 return;
267 }
268
269 sync_sink = READ_ONCE(ep->sync_sink);
270 if (sync_sink)
271 snd_usb_handle_sync_urb(sync_sink, ep, urb);
272
273 call_retire_callback(ep, urb);
274}
275
276static inline bool has_tx_length_quirk(struct snd_usb_audio *chip)
277{
278 return chip->quirk_flags & QUIRK_FLAG_TX_LENGTH;
279}
280
281static void prepare_silent_urb(struct snd_usb_endpoint *ep,
282 struct snd_urb_ctx *ctx)
283{
284 struct urb *urb = ctx->urb;
285 unsigned int offs = 0;
286 unsigned int extra = 0;
287 __le32 packet_length;
288 int i;
289
290 /* For tx_length_quirk, put packet length at start of packet */
291 if (has_tx_length_quirk(ep->chip))
292 extra = sizeof(packet_length);
293
294 for (i = 0; i < ctx->packets; ++i) {
295 unsigned int offset;
296 unsigned int length;
297 int counts;
298
299 counts = snd_usb_endpoint_next_packet_size(ep, ctx, i, 0);
300 length = counts * ep->stride; /* number of silent bytes */
301 offset = offs * ep->stride + extra * i;
302 urb->iso_frame_desc[i].offset = offset;
303 urb->iso_frame_desc[i].length = length + extra;
304 if (extra) {
305 packet_length = cpu_to_le32(length);
306 memcpy(urb->transfer_buffer + offset,
307 &packet_length, sizeof(packet_length));
308 }
309 memset(urb->transfer_buffer + offset + extra,
310 ep->silence_value, length);
311 offs += counts;
312 }
313
314 urb->number_of_packets = ctx->packets;
315 urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
316 ctx->queued = 0;
317}
318
319/*
320 * Prepare a PLAYBACK urb for submission to the bus.
321 */
322static int prepare_outbound_urb(struct snd_usb_endpoint *ep,
323 struct snd_urb_ctx *ctx,
324 bool in_stream_lock)
325{
326 struct urb *urb = ctx->urb;
327 unsigned char *cp = urb->transfer_buffer;
328 struct snd_usb_substream *data_subs;
329
330 urb->dev = ep->chip->dev; /* we need to set this at each time */
331
332 switch (ep->type) {
333 case SND_USB_ENDPOINT_TYPE_DATA:
334 data_subs = READ_ONCE(ep->data_subs);
335 if (data_subs && ep->prepare_data_urb)
336 return ep->prepare_data_urb(data_subs, urb, in_stream_lock);
337 /* no data provider, so send silence */
338 prepare_silent_urb(ep, ctx);
339 break;
340
341 case SND_USB_ENDPOINT_TYPE_SYNC:
342 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
343 /*
344 * fill the length and offset of each urb descriptor.
345 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
346 */
347 urb->iso_frame_desc[0].length = 4;
348 urb->iso_frame_desc[0].offset = 0;
349 cp[0] = ep->freqn;
350 cp[1] = ep->freqn >> 8;
351 cp[2] = ep->freqn >> 16;
352 cp[3] = ep->freqn >> 24;
353 } else {
354 /*
355 * fill the length and offset of each urb descriptor.
356 * the fixed 10.14 frequency is passed through the pipe.
357 */
358 urb->iso_frame_desc[0].length = 3;
359 urb->iso_frame_desc[0].offset = 0;
360 cp[0] = ep->freqn >> 2;
361 cp[1] = ep->freqn >> 10;
362 cp[2] = ep->freqn >> 18;
363 }
364
365 break;
366 }
367 return 0;
368}
369
370/*
371 * Prepare a CAPTURE or SYNC urb for submission to the bus.
372 */
373static int prepare_inbound_urb(struct snd_usb_endpoint *ep,
374 struct snd_urb_ctx *urb_ctx)
375{
376 int i, offs;
377 struct urb *urb = urb_ctx->urb;
378
379 urb->dev = ep->chip->dev; /* we need to set this at each time */
380
381 switch (ep->type) {
382 case SND_USB_ENDPOINT_TYPE_DATA:
383 offs = 0;
384 for (i = 0; i < urb_ctx->packets; i++) {
385 urb->iso_frame_desc[i].offset = offs;
386 urb->iso_frame_desc[i].length = ep->curpacksize;
387 offs += ep->curpacksize;
388 }
389
390 urb->transfer_buffer_length = offs;
391 urb->number_of_packets = urb_ctx->packets;
392 break;
393
394 case SND_USB_ENDPOINT_TYPE_SYNC:
395 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
396 urb->iso_frame_desc[0].offset = 0;
397 break;
398 }
399 return 0;
400}
401
402/* notify an error as XRUN to the assigned PCM data substream */
403static void notify_xrun(struct snd_usb_endpoint *ep)
404{
405 struct snd_usb_substream *data_subs;
406 struct snd_pcm_substream *psubs;
407
408 data_subs = READ_ONCE(ep->data_subs);
409 if (!data_subs)
410 return;
411 psubs = data_subs->pcm_substream;
412 if (psubs && psubs->runtime &&
413 psubs->runtime->state == SNDRV_PCM_STATE_RUNNING)
414 snd_pcm_stop_xrun(psubs);
415}
416
417static struct snd_usb_packet_info *
418next_packet_fifo_enqueue(struct snd_usb_endpoint *ep)
419{
420 struct snd_usb_packet_info *p;
421
422 p = ep->next_packet + (ep->next_packet_head + ep->next_packet_queued) %
423 ARRAY_SIZE(ep->next_packet);
424 ep->next_packet_queued++;
425 return p;
426}
427
428static struct snd_usb_packet_info *
429next_packet_fifo_dequeue(struct snd_usb_endpoint *ep)
430{
431 struct snd_usb_packet_info *p;
432
433 p = ep->next_packet + ep->next_packet_head;
434 ep->next_packet_head++;
435 ep->next_packet_head %= ARRAY_SIZE(ep->next_packet);
436 ep->next_packet_queued--;
437 return p;
438}
439
440static void push_back_to_ready_list(struct snd_usb_endpoint *ep,
441 struct snd_urb_ctx *ctx)
442{
443 unsigned long flags;
444
445 spin_lock_irqsave(&ep->lock, flags);
446 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
447 spin_unlock_irqrestore(&ep->lock, flags);
448}
449
450/*
451 * Send output urbs that have been prepared previously. URBs are dequeued
452 * from ep->ready_playback_urbs and in case there aren't any available
453 * or there are no packets that have been prepared, this function does
454 * nothing.
455 *
456 * The reason why the functionality of sending and preparing URBs is separated
457 * is that host controllers don't guarantee the order in which they return
458 * inbound and outbound packets to their submitters.
459 *
460 * This function is used both for implicit feedback endpoints and in low-
461 * latency playback mode.
462 */
463int snd_usb_queue_pending_output_urbs(struct snd_usb_endpoint *ep,
464 bool in_stream_lock)
465{
466 bool implicit_fb = snd_usb_endpoint_implicit_feedback_sink(ep);
467
468 while (ep_state_running(ep)) {
469
470 unsigned long flags;
471 struct snd_usb_packet_info *packet;
472 struct snd_urb_ctx *ctx = NULL;
473 int err, i;
474
475 spin_lock_irqsave(&ep->lock, flags);
476 if ((!implicit_fb || ep->next_packet_queued > 0) &&
477 !list_empty(&ep->ready_playback_urbs)) {
478 /* take URB out of FIFO */
479 ctx = list_first_entry(&ep->ready_playback_urbs,
480 struct snd_urb_ctx, ready_list);
481 list_del_init(&ctx->ready_list);
482 if (implicit_fb)
483 packet = next_packet_fifo_dequeue(ep);
484 }
485 spin_unlock_irqrestore(&ep->lock, flags);
486
487 if (ctx == NULL)
488 break;
489
490 /* copy over the length information */
491 if (implicit_fb) {
492 for (i = 0; i < packet->packets; i++)
493 ctx->packet_size[i] = packet->packet_size[i];
494 }
495
496 /* call the data handler to fill in playback data */
497 err = prepare_outbound_urb(ep, ctx, in_stream_lock);
498 /* can be stopped during prepare callback */
499 if (unlikely(!ep_state_running(ep)))
500 break;
501 if (err < 0) {
502 /* push back to ready list again for -EAGAIN */
503 if (err == -EAGAIN) {
504 push_back_to_ready_list(ep, ctx);
505 break;
506 }
507
508 if (!in_stream_lock)
509 notify_xrun(ep);
510 return -EPIPE;
511 }
512
513 if (!atomic_read(&ep->chip->shutdown))
514 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
515 else
516 err = -ENODEV;
517 if (err < 0) {
518 if (!atomic_read(&ep->chip->shutdown)) {
519 usb_audio_err(ep->chip,
520 "Unable to submit urb #%d: %d at %s\n",
521 ctx->index, err, __func__);
522 if (!in_stream_lock)
523 notify_xrun(ep);
524 }
525 return -EPIPE;
526 }
527
528 set_bit(ctx->index, &ep->active_mask);
529 atomic_inc(&ep->submitted_urbs);
530 }
531
532 return 0;
533}
534
535/*
536 * complete callback for urbs
537 */
538static void snd_complete_urb(struct urb *urb)
539{
540 struct snd_urb_ctx *ctx = urb->context;
541 struct snd_usb_endpoint *ep = ctx->ep;
542 int err;
543
544 if (unlikely(urb->status == -ENOENT || /* unlinked */
545 urb->status == -ENODEV || /* device removed */
546 urb->status == -ECONNRESET || /* unlinked */
547 urb->status == -ESHUTDOWN)) /* device disabled */
548 goto exit_clear;
549 /* device disconnected */
550 if (unlikely(atomic_read(&ep->chip->shutdown)))
551 goto exit_clear;
552
553 if (unlikely(!ep_state_running(ep)))
554 goto exit_clear;
555
556 if (usb_pipeout(ep->pipe)) {
557 retire_outbound_urb(ep, ctx);
558 /* can be stopped during retire callback */
559 if (unlikely(!ep_state_running(ep)))
560 goto exit_clear;
561
562 /* in low-latency and implicit-feedback modes, push back the
563 * URB to ready list at first, then process as much as possible
564 */
565 if (ep->lowlatency_playback ||
566 snd_usb_endpoint_implicit_feedback_sink(ep)) {
567 push_back_to_ready_list(ep, ctx);
568 clear_bit(ctx->index, &ep->active_mask);
569 snd_usb_queue_pending_output_urbs(ep, false);
570 /* decrement at last, and check xrun */
571 if (atomic_dec_and_test(&ep->submitted_urbs) &&
572 !snd_usb_endpoint_implicit_feedback_sink(ep))
573 notify_xrun(ep);
574 return;
575 }
576
577 /* in non-lowlatency mode, no error handling for prepare */
578 prepare_outbound_urb(ep, ctx, false);
579 /* can be stopped during prepare callback */
580 if (unlikely(!ep_state_running(ep)))
581 goto exit_clear;
582 } else {
583 retire_inbound_urb(ep, ctx);
584 /* can be stopped during retire callback */
585 if (unlikely(!ep_state_running(ep)))
586 goto exit_clear;
587
588 prepare_inbound_urb(ep, ctx);
589 }
590
591 if (!atomic_read(&ep->chip->shutdown))
592 err = usb_submit_urb(urb, GFP_ATOMIC);
593 else
594 err = -ENODEV;
595 if (err == 0)
596 return;
597
598 if (!atomic_read(&ep->chip->shutdown)) {
599 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
600 notify_xrun(ep);
601 }
602
603exit_clear:
604 clear_bit(ctx->index, &ep->active_mask);
605 atomic_dec(&ep->submitted_urbs);
606}
607
608/*
609 * Find or create a refcount object for the given interface
610 *
611 * The objects are released altogether in snd_usb_endpoint_free_all()
612 */
613static struct snd_usb_iface_ref *
614iface_ref_find(struct snd_usb_audio *chip, int iface)
615{
616 struct snd_usb_iface_ref *ip;
617
618 list_for_each_entry(ip, &chip->iface_ref_list, list)
619 if (ip->iface == iface)
620 return ip;
621
622 ip = kzalloc(sizeof(*ip), GFP_KERNEL);
623 if (!ip)
624 return NULL;
625 ip->iface = iface;
626 list_add_tail(&ip->list, &chip->iface_ref_list);
627 return ip;
628}
629
630/* Similarly, a refcount object for clock */
631static struct snd_usb_clock_ref *
632clock_ref_find(struct snd_usb_audio *chip, int clock)
633{
634 struct snd_usb_clock_ref *ref;
635
636 list_for_each_entry(ref, &chip->clock_ref_list, list)
637 if (ref->clock == clock)
638 return ref;
639
640 ref = kzalloc(sizeof(*ref), GFP_KERNEL);
641 if (!ref)
642 return NULL;
643 ref->clock = clock;
644 atomic_set(&ref->locked, 0);
645 list_add_tail(&ref->list, &chip->clock_ref_list);
646 return ref;
647}
648
649/*
650 * Get the existing endpoint object corresponding EP
651 * Returns NULL if not present.
652 */
653struct snd_usb_endpoint *
654snd_usb_get_endpoint(struct snd_usb_audio *chip, int ep_num)
655{
656 struct snd_usb_endpoint *ep;
657
658 list_for_each_entry(ep, &chip->ep_list, list) {
659 if (ep->ep_num == ep_num)
660 return ep;
661 }
662
663 return NULL;
664}
665
666#define ep_type_name(type) \
667 (type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync")
668
669/**
670 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
671 *
672 * @chip: The chip
673 * @ep_num: The number of the endpoint to use
674 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
675 *
676 * If the requested endpoint has not been added to the given chip before,
677 * a new instance is created.
678 *
679 * Returns zero on success or a negative error code.
680 *
681 * New endpoints will be added to chip->ep_list and freed by
682 * calling snd_usb_endpoint_free_all().
683 *
684 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
685 * bNumEndpoints > 1 beforehand.
686 */
687int snd_usb_add_endpoint(struct snd_usb_audio *chip, int ep_num, int type)
688{
689 struct snd_usb_endpoint *ep;
690 bool is_playback;
691
692 ep = snd_usb_get_endpoint(chip, ep_num);
693 if (ep)
694 return 0;
695
696 usb_audio_dbg(chip, "Creating new %s endpoint #%x\n",
697 ep_type_name(type),
698 ep_num);
699 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
700 if (!ep)
701 return -ENOMEM;
702
703 ep->chip = chip;
704 spin_lock_init(&ep->lock);
705 ep->type = type;
706 ep->ep_num = ep_num;
707 INIT_LIST_HEAD(&ep->ready_playback_urbs);
708 atomic_set(&ep->submitted_urbs, 0);
709
710 is_playback = ((ep_num & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT);
711 ep_num &= USB_ENDPOINT_NUMBER_MASK;
712 if (is_playback)
713 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
714 else
715 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
716
717 list_add_tail(&ep->list, &chip->ep_list);
718 return 0;
719}
720
721/* Set up syncinterval and maxsyncsize for a sync EP */
722static void endpoint_set_syncinterval(struct snd_usb_audio *chip,
723 struct snd_usb_endpoint *ep)
724{
725 struct usb_host_interface *alts;
726 struct usb_endpoint_descriptor *desc;
727
728 alts = snd_usb_get_host_interface(chip, ep->iface, ep->altsetting);
729 if (!alts)
730 return;
731
732 desc = get_endpoint(alts, ep->ep_idx);
733 if (desc->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
734 desc->bRefresh >= 1 && desc->bRefresh <= 9)
735 ep->syncinterval = desc->bRefresh;
736 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
737 ep->syncinterval = 1;
738 else if (desc->bInterval >= 1 && desc->bInterval <= 16)
739 ep->syncinterval = desc->bInterval - 1;
740 else
741 ep->syncinterval = 3;
742
743 ep->syncmaxsize = le16_to_cpu(desc->wMaxPacketSize);
744}
745
746static bool endpoint_compatible(struct snd_usb_endpoint *ep,
747 const struct audioformat *fp,
748 const struct snd_pcm_hw_params *params)
749{
750 if (!ep->opened)
751 return false;
752 if (ep->cur_audiofmt != fp)
753 return false;
754 if (ep->cur_rate != params_rate(params) ||
755 ep->cur_format != params_format(params) ||
756 ep->cur_period_frames != params_period_size(params) ||
757 ep->cur_buffer_periods != params_periods(params))
758 return false;
759 return true;
760}
761
762/*
763 * Check whether the given fp and hw params are compatible with the current
764 * setup of the target EP for implicit feedback sync
765 */
766bool snd_usb_endpoint_compatible(struct snd_usb_audio *chip,
767 struct snd_usb_endpoint *ep,
768 const struct audioformat *fp,
769 const struct snd_pcm_hw_params *params)
770{
771 bool ret;
772
773 mutex_lock(&chip->mutex);
774 ret = endpoint_compatible(ep, fp, params);
775 mutex_unlock(&chip->mutex);
776 return ret;
777}
778
779/*
780 * snd_usb_endpoint_open: Open the endpoint
781 *
782 * Called from hw_params to assign the endpoint to the substream.
783 * It's reference-counted, and only the first opener is allowed to set up
784 * arbitrary parameters. The later opener must be compatible with the
785 * former opened parameters.
786 * The endpoint needs to be closed via snd_usb_endpoint_close() later.
787 *
788 * Note that this function doesn't configure the endpoint. The substream
789 * needs to set it up later via snd_usb_endpoint_set_params() and
790 * snd_usb_endpoint_prepare().
791 */
792struct snd_usb_endpoint *
793snd_usb_endpoint_open(struct snd_usb_audio *chip,
794 const struct audioformat *fp,
795 const struct snd_pcm_hw_params *params,
796 bool is_sync_ep,
797 bool fixed_rate)
798{
799 struct snd_usb_endpoint *ep;
800 int ep_num = is_sync_ep ? fp->sync_ep : fp->endpoint;
801
802 mutex_lock(&chip->mutex);
803 ep = snd_usb_get_endpoint(chip, ep_num);
804 if (!ep) {
805 usb_audio_err(chip, "Cannot find EP 0x%x to open\n", ep_num);
806 goto unlock;
807 }
808
809 if (!ep->opened) {
810 if (is_sync_ep) {
811 ep->iface = fp->sync_iface;
812 ep->altsetting = fp->sync_altsetting;
813 ep->ep_idx = fp->sync_ep_idx;
814 } else {
815 ep->iface = fp->iface;
816 ep->altsetting = fp->altsetting;
817 ep->ep_idx = fp->ep_idx;
818 }
819 usb_audio_dbg(chip, "Open EP 0x%x, iface=%d:%d, idx=%d\n",
820 ep_num, ep->iface, ep->altsetting, ep->ep_idx);
821
822 ep->iface_ref = iface_ref_find(chip, ep->iface);
823 if (!ep->iface_ref) {
824 ep = NULL;
825 goto unlock;
826 }
827
828 if (fp->protocol != UAC_VERSION_1) {
829 ep->clock_ref = clock_ref_find(chip, fp->clock);
830 if (!ep->clock_ref) {
831 ep = NULL;
832 goto unlock;
833 }
834 ep->clock_ref->opened++;
835 }
836
837 ep->cur_audiofmt = fp;
838 ep->cur_channels = fp->channels;
839 ep->cur_rate = params_rate(params);
840 ep->cur_format = params_format(params);
841 ep->cur_frame_bytes = snd_pcm_format_physical_width(ep->cur_format) *
842 ep->cur_channels / 8;
843 ep->cur_period_frames = params_period_size(params);
844 ep->cur_period_bytes = ep->cur_period_frames * ep->cur_frame_bytes;
845 ep->cur_buffer_periods = params_periods(params);
846
847 if (ep->type == SND_USB_ENDPOINT_TYPE_SYNC)
848 endpoint_set_syncinterval(chip, ep);
849
850 ep->implicit_fb_sync = fp->implicit_fb;
851 ep->need_setup = true;
852 ep->need_prepare = true;
853 ep->fixed_rate = fixed_rate;
854
855 usb_audio_dbg(chip, " channels=%d, rate=%d, format=%s, period_bytes=%d, periods=%d, implicit_fb=%d\n",
856 ep->cur_channels, ep->cur_rate,
857 snd_pcm_format_name(ep->cur_format),
858 ep->cur_period_bytes, ep->cur_buffer_periods,
859 ep->implicit_fb_sync);
860
861 } else {
862 if (WARN_ON(!ep->iface_ref)) {
863 ep = NULL;
864 goto unlock;
865 }
866
867 if (!endpoint_compatible(ep, fp, params)) {
868 usb_audio_err(chip, "Incompatible EP setup for 0x%x\n",
869 ep_num);
870 ep = NULL;
871 goto unlock;
872 }
873
874 usb_audio_dbg(chip, "Reopened EP 0x%x (count %d)\n",
875 ep_num, ep->opened);
876 }
877
878 if (!ep->iface_ref->opened++)
879 ep->iface_ref->need_setup = true;
880
881 ep->opened++;
882
883 unlock:
884 mutex_unlock(&chip->mutex);
885 return ep;
886}
887
888/*
889 * snd_usb_endpoint_set_sync: Link data and sync endpoints
890 *
891 * Pass NULL to sync_ep to unlink again
892 */
893void snd_usb_endpoint_set_sync(struct snd_usb_audio *chip,
894 struct snd_usb_endpoint *data_ep,
895 struct snd_usb_endpoint *sync_ep)
896{
897 data_ep->sync_source = sync_ep;
898}
899
900/*
901 * Set data endpoint callbacks and the assigned data stream
902 *
903 * Called at PCM trigger and cleanups.
904 * Pass NULL to deactivate each callback.
905 */
906void snd_usb_endpoint_set_callback(struct snd_usb_endpoint *ep,
907 int (*prepare)(struct snd_usb_substream *subs,
908 struct urb *urb,
909 bool in_stream_lock),
910 void (*retire)(struct snd_usb_substream *subs,
911 struct urb *urb),
912 struct snd_usb_substream *data_subs)
913{
914 ep->prepare_data_urb = prepare;
915 ep->retire_data_urb = retire;
916 if (data_subs)
917 ep->lowlatency_playback = data_subs->lowlatency_playback;
918 else
919 ep->lowlatency_playback = false;
920 WRITE_ONCE(ep->data_subs, data_subs);
921}
922
923static int endpoint_set_interface(struct snd_usb_audio *chip,
924 struct snd_usb_endpoint *ep,
925 bool set)
926{
927 int altset = set ? ep->altsetting : 0;
928 int err;
929 int retries = 0;
930 const int max_retries = 5;
931
932 if (ep->iface_ref->altset == altset)
933 return 0;
934 /* already disconnected? */
935 if (unlikely(atomic_read(&chip->shutdown)))
936 return -ENODEV;
937
938 usb_audio_dbg(chip, "Setting usb interface %d:%d for EP 0x%x\n",
939 ep->iface, altset, ep->ep_num);
940retry:
941 err = usb_set_interface(chip->dev, ep->iface, altset);
942 if (err < 0) {
943 if (err == -EPROTO && ++retries <= max_retries) {
944 msleep(5 * (1 << (retries - 1)));
945 goto retry;
946 }
947 usb_audio_err_ratelimited(
948 chip, "%d:%d: usb_set_interface failed (%d)\n",
949 ep->iface, altset, err);
950 return err;
951 }
952
953 if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY)
954 msleep(50);
955 ep->iface_ref->altset = altset;
956 return 0;
957}
958
959/*
960 * snd_usb_endpoint_close: Close the endpoint
961 *
962 * Unreference the already opened endpoint via snd_usb_endpoint_open().
963 */
964void snd_usb_endpoint_close(struct snd_usb_audio *chip,
965 struct snd_usb_endpoint *ep)
966{
967 mutex_lock(&chip->mutex);
968 usb_audio_dbg(chip, "Closing EP 0x%x (count %d)\n",
969 ep->ep_num, ep->opened);
970
971 if (!--ep->iface_ref->opened &&
972 !(chip->quirk_flags & QUIRK_FLAG_IFACE_SKIP_CLOSE))
973 endpoint_set_interface(chip, ep, false);
974
975 if (!--ep->opened) {
976 if (ep->clock_ref) {
977 if (!--ep->clock_ref->opened)
978 ep->clock_ref->rate = 0;
979 }
980 ep->iface = 0;
981 ep->altsetting = 0;
982 ep->cur_audiofmt = NULL;
983 ep->cur_rate = 0;
984 ep->iface_ref = NULL;
985 ep->clock_ref = NULL;
986 usb_audio_dbg(chip, "EP 0x%x closed\n", ep->ep_num);
987 }
988 mutex_unlock(&chip->mutex);
989}
990
991/* Prepare for suspening EP, called from the main suspend handler */
992void snd_usb_endpoint_suspend(struct snd_usb_endpoint *ep)
993{
994 ep->need_prepare = true;
995 if (ep->iface_ref)
996 ep->iface_ref->need_setup = true;
997 if (ep->clock_ref)
998 ep->clock_ref->rate = 0;
999}
1000
1001/*
1002 * wait until all urbs are processed.
1003 */
1004static int wait_clear_urbs(struct snd_usb_endpoint *ep)
1005{
1006 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
1007 int alive;
1008
1009 if (atomic_read(&ep->state) != EP_STATE_STOPPING)
1010 return 0;
1011
1012 do {
1013 alive = atomic_read(&ep->submitted_urbs);
1014 if (!alive)
1015 break;
1016
1017 schedule_timeout_uninterruptible(1);
1018 } while (time_before(jiffies, end_time));
1019
1020 if (alive)
1021 usb_audio_err(ep->chip,
1022 "timeout: still %d active urbs on EP #%x\n",
1023 alive, ep->ep_num);
1024
1025 if (ep_state_update(ep, EP_STATE_STOPPING, EP_STATE_STOPPED)) {
1026 ep->sync_sink = NULL;
1027 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
1028 }
1029
1030 return 0;
1031}
1032
1033/* sync the pending stop operation;
1034 * this function itself doesn't trigger the stop operation
1035 */
1036void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
1037{
1038 if (ep)
1039 wait_clear_urbs(ep);
1040}
1041
1042/*
1043 * Stop active urbs
1044 *
1045 * This function moves the EP to STOPPING state if it's being RUNNING.
1046 */
1047static int stop_urbs(struct snd_usb_endpoint *ep, bool force, bool keep_pending)
1048{
1049 unsigned int i;
1050 unsigned long flags;
1051
1052 if (!force && atomic_read(&ep->running))
1053 return -EBUSY;
1054
1055 if (!ep_state_update(ep, EP_STATE_RUNNING, EP_STATE_STOPPING))
1056 return 0;
1057
1058 spin_lock_irqsave(&ep->lock, flags);
1059 INIT_LIST_HEAD(&ep->ready_playback_urbs);
1060 ep->next_packet_head = 0;
1061 ep->next_packet_queued = 0;
1062 spin_unlock_irqrestore(&ep->lock, flags);
1063
1064 if (keep_pending)
1065 return 0;
1066
1067 for (i = 0; i < ep->nurbs; i++) {
1068 if (test_bit(i, &ep->active_mask)) {
1069 if (!test_and_set_bit(i, &ep->unlink_mask)) {
1070 struct urb *u = ep->urb[i].urb;
1071 usb_unlink_urb(u);
1072 }
1073 }
1074 }
1075
1076 return 0;
1077}
1078
1079/*
1080 * release an endpoint's urbs
1081 */
1082static int release_urbs(struct snd_usb_endpoint *ep, bool force)
1083{
1084 int i, err;
1085
1086 /* route incoming urbs to nirvana */
1087 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
1088
1089 /* stop and unlink urbs */
1090 err = stop_urbs(ep, force, false);
1091 if (err)
1092 return err;
1093
1094 wait_clear_urbs(ep);
1095
1096 for (i = 0; i < ep->nurbs; i++)
1097 release_urb_ctx(&ep->urb[i]);
1098
1099 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
1100 ep->syncbuf, ep->sync_dma);
1101
1102 ep->syncbuf = NULL;
1103 ep->nurbs = 0;
1104 return 0;
1105}
1106
1107/*
1108 * configure a data endpoint
1109 */
1110static int data_ep_set_params(struct snd_usb_endpoint *ep)
1111{
1112 struct snd_usb_audio *chip = ep->chip;
1113 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
1114 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
1115 unsigned int max_urbs, i;
1116 const struct audioformat *fmt = ep->cur_audiofmt;
1117 int frame_bits = ep->cur_frame_bytes * 8;
1118 int tx_length_quirk = (has_tx_length_quirk(chip) &&
1119 usb_pipeout(ep->pipe));
1120
1121 usb_audio_dbg(chip, "Setting params for data EP 0x%x, pipe 0x%x\n",
1122 ep->ep_num, ep->pipe);
1123
1124 if (ep->cur_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
1125 /*
1126 * When operating in DSD DOP mode, the size of a sample frame
1127 * in hardware differs from the actual physical format width
1128 * because we need to make room for the DOP markers.
1129 */
1130 frame_bits += ep->cur_channels << 3;
1131 }
1132
1133 ep->datainterval = fmt->datainterval;
1134 ep->stride = frame_bits >> 3;
1135
1136 switch (ep->cur_format) {
1137 case SNDRV_PCM_FORMAT_U8:
1138 ep->silence_value = 0x80;
1139 break;
1140 case SNDRV_PCM_FORMAT_DSD_U8:
1141 case SNDRV_PCM_FORMAT_DSD_U16_LE:
1142 case SNDRV_PCM_FORMAT_DSD_U32_LE:
1143 case SNDRV_PCM_FORMAT_DSD_U16_BE:
1144 case SNDRV_PCM_FORMAT_DSD_U32_BE:
1145 ep->silence_value = 0x69;
1146 break;
1147 default:
1148 ep->silence_value = 0;
1149 }
1150
1151 /* assume max. frequency is 50% higher than nominal */
1152 ep->freqmax = ep->freqn + (ep->freqn >> 1);
1153 /* Round up freqmax to nearest integer in order to calculate maximum
1154 * packet size, which must represent a whole number of frames.
1155 * This is accomplished by adding 0x0.ffff before converting the
1156 * Q16.16 format into integer.
1157 * In order to accurately calculate the maximum packet size when
1158 * the data interval is more than 1 (i.e. ep->datainterval > 0),
1159 * multiply by the data interval prior to rounding. For instance,
1160 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
1161 * frames with a data interval of 1, but 11 (10.25) frames with a
1162 * data interval of 2.
1163 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
1164 * maximum datainterval value of 3, at USB full speed, higher for
1165 * USB high speed, noting that ep->freqmax is in units of
1166 * frames per packet in Q16.16 format.)
1167 */
1168 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
1169 (frame_bits >> 3);
1170 if (tx_length_quirk)
1171 maxsize += sizeof(__le32); /* Space for length descriptor */
1172 /* but wMaxPacketSize might reduce this */
1173 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
1174 /* whatever fits into a max. size packet */
1175 unsigned int data_maxsize = maxsize = ep->maxpacksize;
1176
1177 if (tx_length_quirk)
1178 /* Need to remove the length descriptor to calc freq */
1179 data_maxsize -= sizeof(__le32);
1180 ep->freqmax = (data_maxsize / (frame_bits >> 3))
1181 << (16 - ep->datainterval);
1182 }
1183
1184 if (ep->fill_max)
1185 ep->curpacksize = ep->maxpacksize;
1186 else
1187 ep->curpacksize = maxsize;
1188
1189 if (snd_usb_get_speed(chip->dev) != USB_SPEED_FULL) {
1190 packs_per_ms = 8 >> ep->datainterval;
1191 max_packs_per_urb = MAX_PACKS_HS;
1192 } else {
1193 packs_per_ms = 1;
1194 max_packs_per_urb = MAX_PACKS;
1195 }
1196 if (ep->sync_source && !ep->implicit_fb_sync)
1197 max_packs_per_urb = min(max_packs_per_urb,
1198 1U << ep->sync_source->syncinterval);
1199 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
1200
1201 /*
1202 * Capture endpoints need to use small URBs because there's no way
1203 * to tell in advance where the next period will end, and we don't
1204 * want the next URB to complete much after the period ends.
1205 *
1206 * Playback endpoints with implicit sync much use the same parameters
1207 * as their corresponding capture endpoint.
1208 */
1209 if (usb_pipein(ep->pipe) || ep->implicit_fb_sync) {
1210
1211 /* make capture URBs <= 1 ms and smaller than a period */
1212 urb_packs = min(max_packs_per_urb, packs_per_ms);
1213 while (urb_packs > 1 && urb_packs * maxsize >= ep->cur_period_bytes)
1214 urb_packs >>= 1;
1215 ep->nurbs = MAX_URBS;
1216
1217 /*
1218 * Playback endpoints without implicit sync are adjusted so that
1219 * a period fits as evenly as possible in the smallest number of
1220 * URBs. The total number of URBs is adjusted to the size of the
1221 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
1222 */
1223 } else {
1224 /* determine how small a packet can be */
1225 minsize = (ep->freqn >> (16 - ep->datainterval)) *
1226 (frame_bits >> 3);
1227 /* with sync from device, assume it can be 12% lower */
1228 if (ep->sync_source)
1229 minsize -= minsize >> 3;
1230 minsize = max(minsize, 1u);
1231
1232 /* how many packets will contain an entire ALSA period? */
1233 max_packs_per_period = DIV_ROUND_UP(ep->cur_period_bytes, minsize);
1234
1235 /* how many URBs will contain a period? */
1236 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
1237 max_packs_per_urb);
1238 /* how many packets are needed in each URB? */
1239 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
1240
1241 /* limit the number of frames in a single URB */
1242 ep->max_urb_frames = DIV_ROUND_UP(ep->cur_period_frames,
1243 urbs_per_period);
1244
1245 /* try to use enough URBs to contain an entire ALSA buffer */
1246 max_urbs = min((unsigned) MAX_URBS,
1247 MAX_QUEUE * packs_per_ms / urb_packs);
1248 ep->nurbs = min(max_urbs, urbs_per_period * ep->cur_buffer_periods);
1249 }
1250
1251 /* allocate and initialize data urbs */
1252 for (i = 0; i < ep->nurbs; i++) {
1253 struct snd_urb_ctx *u = &ep->urb[i];
1254 u->index = i;
1255 u->ep = ep;
1256 u->packets = urb_packs;
1257 u->buffer_size = maxsize * u->packets;
1258
1259 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
1260 u->packets++; /* for transfer delimiter */
1261 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
1262 if (!u->urb)
1263 goto out_of_memory;
1264
1265 u->urb->transfer_buffer =
1266 usb_alloc_coherent(chip->dev, u->buffer_size,
1267 GFP_KERNEL, &u->urb->transfer_dma);
1268 if (!u->urb->transfer_buffer)
1269 goto out_of_memory;
1270 u->urb->pipe = ep->pipe;
1271 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1272 u->urb->interval = 1 << ep->datainterval;
1273 u->urb->context = u;
1274 u->urb->complete = snd_complete_urb;
1275 INIT_LIST_HEAD(&u->ready_list);
1276 }
1277
1278 return 0;
1279
1280out_of_memory:
1281 release_urbs(ep, false);
1282 return -ENOMEM;
1283}
1284
1285/*
1286 * configure a sync endpoint
1287 */
1288static int sync_ep_set_params(struct snd_usb_endpoint *ep)
1289{
1290 struct snd_usb_audio *chip = ep->chip;
1291 int i;
1292
1293 usb_audio_dbg(chip, "Setting params for sync EP 0x%x, pipe 0x%x\n",
1294 ep->ep_num, ep->pipe);
1295
1296 ep->syncbuf = usb_alloc_coherent(chip->dev, SYNC_URBS * 4,
1297 GFP_KERNEL, &ep->sync_dma);
1298 if (!ep->syncbuf)
1299 return -ENOMEM;
1300
1301 ep->nurbs = SYNC_URBS;
1302 for (i = 0; i < SYNC_URBS; i++) {
1303 struct snd_urb_ctx *u = &ep->urb[i];
1304 u->index = i;
1305 u->ep = ep;
1306 u->packets = 1;
1307 u->urb = usb_alloc_urb(1, GFP_KERNEL);
1308 if (!u->urb)
1309 goto out_of_memory;
1310 u->urb->transfer_buffer = ep->syncbuf + i * 4;
1311 u->urb->transfer_dma = ep->sync_dma + i * 4;
1312 u->urb->transfer_buffer_length = 4;
1313 u->urb->pipe = ep->pipe;
1314 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1315 u->urb->number_of_packets = 1;
1316 u->urb->interval = 1 << ep->syncinterval;
1317 u->urb->context = u;
1318 u->urb->complete = snd_complete_urb;
1319 }
1320
1321 return 0;
1322
1323out_of_memory:
1324 release_urbs(ep, false);
1325 return -ENOMEM;
1326}
1327
1328/* update the rate of the referred clock; return the actual rate */
1329static int update_clock_ref_rate(struct snd_usb_audio *chip,
1330 struct snd_usb_endpoint *ep)
1331{
1332 struct snd_usb_clock_ref *clock = ep->clock_ref;
1333 int rate = ep->cur_rate;
1334
1335 if (!clock || clock->rate == rate)
1336 return rate;
1337 if (clock->rate) {
1338 if (atomic_read(&clock->locked))
1339 return clock->rate;
1340 if (clock->rate != rate) {
1341 usb_audio_err(chip, "Mismatched sample rate %d vs %d for EP 0x%x\n",
1342 clock->rate, rate, ep->ep_num);
1343 return clock->rate;
1344 }
1345 }
1346 clock->rate = rate;
1347 clock->need_setup = true;
1348 return rate;
1349}
1350
1351/*
1352 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
1353 *
1354 * It's called either from hw_params callback.
1355 * Determine the number of URBs to be used on this endpoint.
1356 * An endpoint must be configured before it can be started.
1357 * An endpoint that is already running can not be reconfigured.
1358 */
1359int snd_usb_endpoint_set_params(struct snd_usb_audio *chip,
1360 struct snd_usb_endpoint *ep)
1361{
1362 const struct audioformat *fmt = ep->cur_audiofmt;
1363 int err = 0;
1364
1365 mutex_lock(&chip->mutex);
1366 if (!ep->need_setup)
1367 goto unlock;
1368
1369 /* release old buffers, if any */
1370 err = release_urbs(ep, false);
1371 if (err < 0)
1372 goto unlock;
1373
1374 ep->datainterval = fmt->datainterval;
1375 ep->maxpacksize = fmt->maxpacksize;
1376 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
1377
1378 if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) {
1379 ep->freqn = get_usb_full_speed_rate(ep->cur_rate);
1380 ep->pps = 1000 >> ep->datainterval;
1381 } else {
1382 ep->freqn = get_usb_high_speed_rate(ep->cur_rate);
1383 ep->pps = 8000 >> ep->datainterval;
1384 }
1385
1386 ep->sample_rem = ep->cur_rate % ep->pps;
1387 ep->packsize[0] = ep->cur_rate / ep->pps;
1388 ep->packsize[1] = (ep->cur_rate + (ep->pps - 1)) / ep->pps;
1389
1390 /* calculate the frequency in 16.16 format */
1391 ep->freqm = ep->freqn;
1392 ep->freqshift = INT_MIN;
1393
1394 ep->phase = 0;
1395
1396 switch (ep->type) {
1397 case SND_USB_ENDPOINT_TYPE_DATA:
1398 err = data_ep_set_params(ep);
1399 break;
1400 case SND_USB_ENDPOINT_TYPE_SYNC:
1401 err = sync_ep_set_params(ep);
1402 break;
1403 default:
1404 err = -EINVAL;
1405 }
1406
1407 usb_audio_dbg(chip, "Set up %d URBS, ret=%d\n", ep->nurbs, err);
1408
1409 if (err < 0)
1410 goto unlock;
1411
1412 /* some unit conversions in runtime */
1413 ep->maxframesize = ep->maxpacksize / ep->cur_frame_bytes;
1414 ep->curframesize = ep->curpacksize / ep->cur_frame_bytes;
1415
1416 err = update_clock_ref_rate(chip, ep);
1417 if (err >= 0) {
1418 ep->need_setup = false;
1419 err = 0;
1420 }
1421
1422 unlock:
1423 mutex_unlock(&chip->mutex);
1424 return err;
1425}
1426
1427static int init_sample_rate(struct snd_usb_audio *chip,
1428 struct snd_usb_endpoint *ep)
1429{
1430 struct snd_usb_clock_ref *clock = ep->clock_ref;
1431 int rate, err;
1432
1433 rate = update_clock_ref_rate(chip, ep);
1434 if (rate < 0)
1435 return rate;
1436 if (clock && !clock->need_setup)
1437 return 0;
1438
1439 if (!ep->fixed_rate) {
1440 err = snd_usb_init_sample_rate(chip, ep->cur_audiofmt, rate);
1441 if (err < 0) {
1442 if (clock)
1443 clock->rate = 0; /* reset rate */
1444 return err;
1445 }
1446 }
1447
1448 if (clock)
1449 clock->need_setup = false;
1450 return 0;
1451}
1452
1453/*
1454 * snd_usb_endpoint_prepare: Prepare the endpoint
1455 *
1456 * This function sets up the EP to be fully usable state.
1457 * It's called either from prepare callback.
1458 * The function checks need_setup flag, and performs nothing unless needed,
1459 * so it's safe to call this multiple times.
1460 *
1461 * This returns zero if unchanged, 1 if the configuration has changed,
1462 * or a negative error code.
1463 */
1464int snd_usb_endpoint_prepare(struct snd_usb_audio *chip,
1465 struct snd_usb_endpoint *ep)
1466{
1467 bool iface_first;
1468 int err = 0;
1469
1470 mutex_lock(&chip->mutex);
1471 if (WARN_ON(!ep->iface_ref))
1472 goto unlock;
1473 if (!ep->need_prepare)
1474 goto unlock;
1475
1476 /* If the interface has been already set up, just set EP parameters */
1477 if (!ep->iface_ref->need_setup) {
1478 /* sample rate setup of UAC1 is per endpoint, and we need
1479 * to update at each EP configuration
1480 */
1481 if (ep->cur_audiofmt->protocol == UAC_VERSION_1) {
1482 err = init_sample_rate(chip, ep);
1483 if (err < 0)
1484 goto unlock;
1485 }
1486 goto done;
1487 }
1488
1489 /* Need to deselect altsetting at first */
1490 endpoint_set_interface(chip, ep, false);
1491
1492 /* Some UAC1 devices (e.g. Yamaha THR10) need the host interface
1493 * to be set up before parameter setups
1494 */
1495 iface_first = ep->cur_audiofmt->protocol == UAC_VERSION_1;
1496 /* Workaround for devices that require the interface setup at first like UAC1 */
1497 if (chip->quirk_flags & QUIRK_FLAG_SET_IFACE_FIRST)
1498 iface_first = true;
1499 if (iface_first) {
1500 err = endpoint_set_interface(chip, ep, true);
1501 if (err < 0)
1502 goto unlock;
1503 }
1504
1505 err = snd_usb_init_pitch(chip, ep->cur_audiofmt);
1506 if (err < 0)
1507 goto unlock;
1508
1509 err = init_sample_rate(chip, ep);
1510 if (err < 0)
1511 goto unlock;
1512
1513 err = snd_usb_select_mode_quirk(chip, ep->cur_audiofmt);
1514 if (err < 0)
1515 goto unlock;
1516
1517 /* for UAC2/3, enable the interface altset here at last */
1518 if (!iface_first) {
1519 err = endpoint_set_interface(chip, ep, true);
1520 if (err < 0)
1521 goto unlock;
1522 }
1523
1524 ep->iface_ref->need_setup = false;
1525
1526 done:
1527 ep->need_prepare = false;
1528 err = 1;
1529
1530unlock:
1531 mutex_unlock(&chip->mutex);
1532 return err;
1533}
1534EXPORT_SYMBOL_GPL(snd_usb_endpoint_prepare);
1535
1536/* get the current rate set to the given clock by any endpoint */
1537int snd_usb_endpoint_get_clock_rate(struct snd_usb_audio *chip, int clock)
1538{
1539 struct snd_usb_clock_ref *ref;
1540 int rate = 0;
1541
1542 if (!clock)
1543 return 0;
1544 mutex_lock(&chip->mutex);
1545 list_for_each_entry(ref, &chip->clock_ref_list, list) {
1546 if (ref->clock == clock) {
1547 rate = ref->rate;
1548 break;
1549 }
1550 }
1551 mutex_unlock(&chip->mutex);
1552 return rate;
1553}
1554
1555/**
1556 * snd_usb_endpoint_start: start an snd_usb_endpoint
1557 *
1558 * @ep: the endpoint to start
1559 *
1560 * A call to this function will increment the running count of the endpoint.
1561 * In case it is not already running, the URBs for this endpoint will be
1562 * submitted. Otherwise, this function does nothing.
1563 *
1564 * Must be balanced to calls of snd_usb_endpoint_stop().
1565 *
1566 * Returns an error if the URB submission failed, 0 in all other cases.
1567 */
1568int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
1569{
1570 bool is_playback = usb_pipeout(ep->pipe);
1571 int err;
1572 unsigned int i;
1573
1574 if (atomic_read(&ep->chip->shutdown))
1575 return -EBADFD;
1576
1577 if (ep->sync_source)
1578 WRITE_ONCE(ep->sync_source->sync_sink, ep);
1579
1580 usb_audio_dbg(ep->chip, "Starting %s EP 0x%x (running %d)\n",
1581 ep_type_name(ep->type), ep->ep_num,
1582 atomic_read(&ep->running));
1583
1584 /* already running? */
1585 if (atomic_inc_return(&ep->running) != 1)
1586 return 0;
1587
1588 if (ep->clock_ref)
1589 atomic_inc(&ep->clock_ref->locked);
1590
1591 ep->active_mask = 0;
1592 ep->unlink_mask = 0;
1593 ep->phase = 0;
1594 ep->sample_accum = 0;
1595
1596 snd_usb_endpoint_start_quirk(ep);
1597
1598 /*
1599 * If this endpoint has a data endpoint as implicit feedback source,
1600 * don't start the urbs here. Instead, mark them all as available,
1601 * wait for the record urbs to return and queue the playback urbs
1602 * from that context.
1603 */
1604
1605 if (!ep_state_update(ep, EP_STATE_STOPPED, EP_STATE_RUNNING))
1606 goto __error;
1607
1608 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1609 !(ep->chip->quirk_flags & QUIRK_FLAG_PLAYBACK_FIRST)) {
1610 usb_audio_dbg(ep->chip, "No URB submission due to implicit fb sync\n");
1611 i = 0;
1612 goto fill_rest;
1613 }
1614
1615 for (i = 0; i < ep->nurbs; i++) {
1616 struct urb *urb = ep->urb[i].urb;
1617
1618 if (snd_BUG_ON(!urb))
1619 goto __error;
1620
1621 if (is_playback)
1622 err = prepare_outbound_urb(ep, urb->context, true);
1623 else
1624 err = prepare_inbound_urb(ep, urb->context);
1625 if (err < 0) {
1626 /* stop filling at applptr */
1627 if (err == -EAGAIN)
1628 break;
1629 usb_audio_dbg(ep->chip,
1630 "EP 0x%x: failed to prepare urb: %d\n",
1631 ep->ep_num, err);
1632 goto __error;
1633 }
1634
1635 if (!atomic_read(&ep->chip->shutdown))
1636 err = usb_submit_urb(urb, GFP_ATOMIC);
1637 else
1638 err = -ENODEV;
1639 if (err < 0) {
1640 if (!atomic_read(&ep->chip->shutdown))
1641 usb_audio_err(ep->chip,
1642 "cannot submit urb %d, error %d: %s\n",
1643 i, err, usb_error_string(err));
1644 goto __error;
1645 }
1646 set_bit(i, &ep->active_mask);
1647 atomic_inc(&ep->submitted_urbs);
1648 }
1649
1650 if (!i) {
1651 usb_audio_dbg(ep->chip, "XRUN at starting EP 0x%x\n",
1652 ep->ep_num);
1653 goto __error;
1654 }
1655
1656 usb_audio_dbg(ep->chip, "%d URBs submitted for EP 0x%x\n",
1657 i, ep->ep_num);
1658
1659 fill_rest:
1660 /* put the remaining URBs to ready list */
1661 if (is_playback) {
1662 for (; i < ep->nurbs; i++)
1663 push_back_to_ready_list(ep, ep->urb + i);
1664 }
1665
1666 return 0;
1667
1668__error:
1669 snd_usb_endpoint_stop(ep, false);
1670 return -EPIPE;
1671}
1672
1673/**
1674 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
1675 *
1676 * @ep: the endpoint to stop (may be NULL)
1677 * @keep_pending: keep in-flight URBs
1678 *
1679 * A call to this function will decrement the running count of the endpoint.
1680 * In case the last user has requested the endpoint stop, the URBs will
1681 * actually be deactivated.
1682 *
1683 * Must be balanced to calls of snd_usb_endpoint_start().
1684 *
1685 * The caller needs to synchronize the pending stop operation via
1686 * snd_usb_endpoint_sync_pending_stop().
1687 */
1688void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep, bool keep_pending)
1689{
1690 if (!ep)
1691 return;
1692
1693 usb_audio_dbg(ep->chip, "Stopping %s EP 0x%x (running %d)\n",
1694 ep_type_name(ep->type), ep->ep_num,
1695 atomic_read(&ep->running));
1696
1697 if (snd_BUG_ON(!atomic_read(&ep->running)))
1698 return;
1699
1700 if (!atomic_dec_return(&ep->running)) {
1701 if (ep->sync_source)
1702 WRITE_ONCE(ep->sync_source->sync_sink, NULL);
1703 stop_urbs(ep, false, keep_pending);
1704 if (ep->clock_ref)
1705 atomic_dec(&ep->clock_ref->locked);
1706
1707 if (ep->chip->quirk_flags & QUIRK_FLAG_FORCE_IFACE_RESET &&
1708 usb_pipeout(ep->pipe)) {
1709 ep->need_prepare = true;
1710 if (ep->iface_ref)
1711 ep->iface_ref->need_setup = true;
1712 }
1713 }
1714}
1715
1716/**
1717 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1718 *
1719 * @ep: the endpoint to release
1720 *
1721 * This function does not care for the endpoint's running count but will tear
1722 * down all the streaming URBs immediately.
1723 */
1724void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1725{
1726 release_urbs(ep, true);
1727}
1728
1729/**
1730 * snd_usb_endpoint_free_all: Free the resources of an snd_usb_endpoint
1731 * @chip: The chip
1732 *
1733 * This free all endpoints and those resources
1734 */
1735void snd_usb_endpoint_free_all(struct snd_usb_audio *chip)
1736{
1737 struct snd_usb_endpoint *ep, *en;
1738 struct snd_usb_iface_ref *ip, *in;
1739 struct snd_usb_clock_ref *cp, *cn;
1740
1741 list_for_each_entry_safe(ep, en, &chip->ep_list, list)
1742 kfree(ep);
1743
1744 list_for_each_entry_safe(ip, in, &chip->iface_ref_list, list)
1745 kfree(ip);
1746
1747 list_for_each_entry_safe(cp, cn, &chip->clock_ref_list, list)
1748 kfree(cp);
1749}
1750
1751/*
1752 * snd_usb_handle_sync_urb: parse an USB sync packet
1753 *
1754 * @ep: the endpoint to handle the packet
1755 * @sender: the sending endpoint
1756 * @urb: the received packet
1757 *
1758 * This function is called from the context of an endpoint that received
1759 * the packet and is used to let another endpoint object handle the payload.
1760 */
1761static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1762 struct snd_usb_endpoint *sender,
1763 const struct urb *urb)
1764{
1765 int shift;
1766 unsigned int f;
1767 unsigned long flags;
1768
1769 snd_BUG_ON(ep == sender);
1770
1771 /*
1772 * In case the endpoint is operating in implicit feedback mode, prepare
1773 * a new outbound URB that has the same layout as the received packet
1774 * and add it to the list of pending urbs. queue_pending_output_urbs()
1775 * will take care of them later.
1776 */
1777 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1778 atomic_read(&ep->running)) {
1779
1780 /* implicit feedback case */
1781 int i, bytes = 0;
1782 struct snd_urb_ctx *in_ctx;
1783 struct snd_usb_packet_info *out_packet;
1784
1785 in_ctx = urb->context;
1786
1787 /* Count overall packet size */
1788 for (i = 0; i < in_ctx->packets; i++)
1789 if (urb->iso_frame_desc[i].status == 0)
1790 bytes += urb->iso_frame_desc[i].actual_length;
1791
1792 /*
1793 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1794 * streaming once it received a 0-byte OUT URB
1795 */
1796 if (bytes == 0)
1797 return;
1798
1799 spin_lock_irqsave(&ep->lock, flags);
1800 if (ep->next_packet_queued >= ARRAY_SIZE(ep->next_packet)) {
1801 spin_unlock_irqrestore(&ep->lock, flags);
1802 usb_audio_err(ep->chip,
1803 "next package FIFO overflow EP 0x%x\n",
1804 ep->ep_num);
1805 notify_xrun(ep);
1806 return;
1807 }
1808
1809 out_packet = next_packet_fifo_enqueue(ep);
1810
1811 /*
1812 * Iterate through the inbound packet and prepare the lengths
1813 * for the output packet. The OUT packet we are about to send
1814 * will have the same amount of payload bytes per stride as the
1815 * IN packet we just received. Since the actual size is scaled
1816 * by the stride, use the sender stride to calculate the length
1817 * in case the number of channels differ between the implicitly
1818 * fed-back endpoint and the synchronizing endpoint.
1819 */
1820
1821 out_packet->packets = in_ctx->packets;
1822 for (i = 0; i < in_ctx->packets; i++) {
1823 if (urb->iso_frame_desc[i].status == 0)
1824 out_packet->packet_size[i] =
1825 urb->iso_frame_desc[i].actual_length / sender->stride;
1826 else
1827 out_packet->packet_size[i] = 0;
1828 }
1829
1830 spin_unlock_irqrestore(&ep->lock, flags);
1831 snd_usb_queue_pending_output_urbs(ep, false);
1832
1833 return;
1834 }
1835
1836 /*
1837 * process after playback sync complete
1838 *
1839 * Full speed devices report feedback values in 10.14 format as samples
1840 * per frame, high speed devices in 16.16 format as samples per
1841 * microframe.
1842 *
1843 * Because the Audio Class 1 spec was written before USB 2.0, many high
1844 * speed devices use a wrong interpretation, some others use an
1845 * entirely different format.
1846 *
1847 * Therefore, we cannot predict what format any particular device uses
1848 * and must detect it automatically.
1849 */
1850
1851 if (urb->iso_frame_desc[0].status != 0 ||
1852 urb->iso_frame_desc[0].actual_length < 3)
1853 return;
1854
1855 f = le32_to_cpup(urb->transfer_buffer);
1856 if (urb->iso_frame_desc[0].actual_length == 3)
1857 f &= 0x00ffffff;
1858 else
1859 f &= 0x0fffffff;
1860
1861 if (f == 0)
1862 return;
1863
1864 if (unlikely(sender->tenor_fb_quirk)) {
1865 /*
1866 * Devices based on Tenor 8802 chipsets (TEAC UD-H01
1867 * and others) sometimes change the feedback value
1868 * by +/- 0x1.0000.
1869 */
1870 if (f < ep->freqn - 0x8000)
1871 f += 0xf000;
1872 else if (f > ep->freqn + 0x8000)
1873 f -= 0xf000;
1874 } else if (unlikely(ep->freqshift == INT_MIN)) {
1875 /*
1876 * The first time we see a feedback value, determine its format
1877 * by shifting it left or right until it matches the nominal
1878 * frequency value. This assumes that the feedback does not
1879 * differ from the nominal value more than +50% or -25%.
1880 */
1881 shift = 0;
1882 while (f < ep->freqn - ep->freqn / 4) {
1883 f <<= 1;
1884 shift++;
1885 }
1886 while (f > ep->freqn + ep->freqn / 2) {
1887 f >>= 1;
1888 shift--;
1889 }
1890 ep->freqshift = shift;
1891 } else if (ep->freqshift >= 0)
1892 f <<= ep->freqshift;
1893 else
1894 f >>= -ep->freqshift;
1895
1896 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1897 /*
1898 * If the frequency looks valid, set it.
1899 * This value is referred to in prepare_playback_urb().
1900 */
1901 spin_lock_irqsave(&ep->lock, flags);
1902 ep->freqm = f;
1903 spin_unlock_irqrestore(&ep->lock, flags);
1904 } else {
1905 /*
1906 * Out of range; maybe the shift value is wrong.
1907 * Reset it so that we autodetect again the next time.
1908 */
1909 ep->freqshift = INT_MIN;
1910 }
1911}
1912
Linux 6.x block layer and io_uring tree(s)