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
24 enum {
25 EP_STATE_STOPPED,
26 EP_STATE_RUNNING,
27 EP_STATE_STOPPING,
28 };
29
30 /* interface refcounting */
31 struct 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 */
40 struct 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 */
80 static 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 */
89 static 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 */
97 static 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
108 static 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
133 static inline bool ep_state_running(struct snd_usb_endpoint *ep)
134 {
135 return atomic_read(&ep->state) == EP_STATE_RUNNING;
136 }
137
138 static 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 */
151 int 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 */
163 static 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 */
189 static 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 */
219 int 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
238 static 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
248 static 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
254 static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
255 struct snd_usb_endpoint *sender,
256 const struct urb *urb);
257
258 static 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
276 static inline bool has_tx_length_quirk(struct snd_usb_audio *chip)
277 {
278 return chip->quirk_flags & QUIRK_FLAG_TX_LENGTH;
279 }
280
281 static 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 */
322 static 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 */
373 static 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 */
403 static 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
412 static struct snd_usb_packet_info *
413 next_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
423 static struct snd_usb_packet_info *
424 next_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
435 static 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 */
458 int 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 */
533 static 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
595 exit_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 */
605 static struct snd_usb_iface_ref *
606 iface_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 */
623 static struct snd_usb_clock_ref *
624 clock_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 */
645 struct snd_usb_endpoint *
646 snd_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 */
679 int 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 */
714 static 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
738 static 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 */
758 bool 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 */
784 struct snd_usb_endpoint *
785 snd_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 */
885 void 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 */
898 void 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
915 static 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 */
946 void 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 */
974 void 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 */
986 static 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 */
1018 void 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 */
1029 static 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 */
1064 static 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 */
1092 static 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
1262 out_of_memory:
1263 release_urbs(ep, false);
1264 return -ENOMEM;
1265 }
1266
1267 /*
1268 * configure a sync endpoint
1269 */
1270 static 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
1305 out_of_memory:
1306 release_urbs(ep, false);
1307 return -ENOMEM;
1308 }
1309
1310 /* update the rate of the referred clock; return the actual rate */
1311 static 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 */
1341 int 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
1409 static 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 */
1446 int 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
1512 unlock:
1513 mutex_unlock(&chip->mutex);
1514 return err;
1515 }
1516
1517 /* get the current rate set to the given clock by any endpoint */
1518 int 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 */
1549 int 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 */
1669 void 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 */
1705 void 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 */
1716 void 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 */
1742 static 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
1894
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