Loading...
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 */
4
5#include <linux/gfp.h>
6#include <linux/init.h>
7#include <linux/ratelimit.h>
8#include <linux/usb.h>
9#include <linux/usb/audio.h>
10#include <linux/slab.h>
11
12#include <sound/core.h>
13#include <sound/pcm.h>
14#include <sound/pcm_params.h>
15
16#include "usbaudio.h"
17#include "helper.h"
18#include "card.h"
19#include "endpoint.h"
20#include "pcm.h"
21#include "quirks.h"
22
23#define EP_FLAG_RUNNING 1
24#define EP_FLAG_STOPPING 2
25
26/*
27 * snd_usb_endpoint is a model that abstracts everything related to an
28 * USB endpoint and its streaming.
29 *
30 * There are functions to activate and deactivate the streaming URBs and
31 * optional callbacks to let the pcm logic handle the actual content of the
32 * packets for playback and record. Thus, the bus streaming and the audio
33 * handlers are fully decoupled.
34 *
35 * There are two different types of endpoints in audio applications.
36 *
37 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
38 * inbound and outbound traffic.
39 *
40 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
41 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
42 * (3 or 4 bytes).
43 *
44 * Each endpoint has to be configured prior to being used by calling
45 * snd_usb_endpoint_set_params().
46 *
47 * The model incorporates a reference counting, so that multiple users
48 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
49 * only the first user will effectively start the URBs, and only the last
50 * one to stop it will tear the URBs down again.
51 */
52
53/*
54 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
55 * this will overflow at approx 524 kHz
56 */
57static inline unsigned get_usb_full_speed_rate(unsigned int rate)
58{
59 return ((rate << 13) + 62) / 125;
60}
61
62/*
63 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
64 * this will overflow at approx 4 MHz
65 */
66static inline unsigned get_usb_high_speed_rate(unsigned int rate)
67{
68 return ((rate << 10) + 62) / 125;
69}
70
71/*
72 * release a urb data
73 */
74static void release_urb_ctx(struct snd_urb_ctx *u)
75{
76 if (u->buffer_size)
77 usb_free_coherent(u->ep->chip->dev, u->buffer_size,
78 u->urb->transfer_buffer,
79 u->urb->transfer_dma);
80 usb_free_urb(u->urb);
81 u->urb = NULL;
82}
83
84static const char *usb_error_string(int err)
85{
86 switch (err) {
87 case -ENODEV:
88 return "no device";
89 case -ENOENT:
90 return "endpoint not enabled";
91 case -EPIPE:
92 return "endpoint stalled";
93 case -ENOSPC:
94 return "not enough bandwidth";
95 case -ESHUTDOWN:
96 return "device disabled";
97 case -EHOSTUNREACH:
98 return "device suspended";
99 case -EINVAL:
100 case -EAGAIN:
101 case -EFBIG:
102 case -EMSGSIZE:
103 return "internal error";
104 default:
105 return "unknown error";
106 }
107}
108
109/**
110 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
111 *
112 * @ep: The snd_usb_endpoint
113 *
114 * Determine whether an endpoint is driven by an implicit feedback
115 * data endpoint source.
116 */
117int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
118{
119 return ep->sync_master &&
120 ep->sync_master->type == SND_USB_ENDPOINT_TYPE_DATA &&
121 ep->type == SND_USB_ENDPOINT_TYPE_DATA &&
122 usb_pipeout(ep->pipe);
123}
124
125/*
126 * For streaming based on information derived from sync endpoints,
127 * prepare_outbound_urb_sizes() will call next_packet_size() to
128 * determine the number of samples to be sent in the next packet.
129 *
130 * For implicit feedback, next_packet_size() is unused.
131 */
132int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep)
133{
134 unsigned long flags;
135 int ret;
136
137 if (ep->fill_max)
138 return ep->maxframesize;
139
140 spin_lock_irqsave(&ep->lock, flags);
141 ep->phase = (ep->phase & 0xffff)
142 + (ep->freqm << ep->datainterval);
143 ret = min(ep->phase >> 16, ep->maxframesize);
144 spin_unlock_irqrestore(&ep->lock, flags);
145
146 return ret;
147}
148
149static void retire_outbound_urb(struct snd_usb_endpoint *ep,
150 struct snd_urb_ctx *urb_ctx)
151{
152 if (ep->retire_data_urb)
153 ep->retire_data_urb(ep->data_subs, urb_ctx->urb);
154}
155
156static void retire_inbound_urb(struct snd_usb_endpoint *ep,
157 struct snd_urb_ctx *urb_ctx)
158{
159 struct urb *urb = urb_ctx->urb;
160
161 if (unlikely(ep->skip_packets > 0)) {
162 ep->skip_packets--;
163 return;
164 }
165
166 if (ep->sync_slave)
167 snd_usb_handle_sync_urb(ep->sync_slave, ep, urb);
168
169 if (ep->retire_data_urb)
170 ep->retire_data_urb(ep->data_subs, urb);
171}
172
173static void prepare_silent_urb(struct snd_usb_endpoint *ep,
174 struct snd_urb_ctx *ctx)
175{
176 struct urb *urb = ctx->urb;
177 unsigned int offs = 0;
178 unsigned int extra = 0;
179 __le32 packet_length;
180 int i;
181
182 /* For tx_length_quirk, put packet length at start of packet */
183 if (ep->chip->tx_length_quirk)
184 extra = sizeof(packet_length);
185
186 for (i = 0; i < ctx->packets; ++i) {
187 unsigned int offset;
188 unsigned int length;
189 int counts;
190
191 if (ctx->packet_size[i])
192 counts = ctx->packet_size[i];
193 else
194 counts = snd_usb_endpoint_next_packet_size(ep);
195
196 length = counts * ep->stride; /* number of silent bytes */
197 offset = offs * ep->stride + extra * i;
198 urb->iso_frame_desc[i].offset = offset;
199 urb->iso_frame_desc[i].length = length + extra;
200 if (extra) {
201 packet_length = cpu_to_le32(length);
202 memcpy(urb->transfer_buffer + offset,
203 &packet_length, sizeof(packet_length));
204 }
205 memset(urb->transfer_buffer + offset + extra,
206 ep->silence_value, length);
207 offs += counts;
208 }
209
210 urb->number_of_packets = ctx->packets;
211 urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
212}
213
214/*
215 * Prepare a PLAYBACK urb for submission to the bus.
216 */
217static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
218 struct snd_urb_ctx *ctx)
219{
220 struct urb *urb = ctx->urb;
221 unsigned char *cp = urb->transfer_buffer;
222
223 urb->dev = ep->chip->dev; /* we need to set this at each time */
224
225 switch (ep->type) {
226 case SND_USB_ENDPOINT_TYPE_DATA:
227 if (ep->prepare_data_urb) {
228 ep->prepare_data_urb(ep->data_subs, urb);
229 } else {
230 /* no data provider, so send silence */
231 prepare_silent_urb(ep, ctx);
232 }
233 break;
234
235 case SND_USB_ENDPOINT_TYPE_SYNC:
236 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
237 /*
238 * fill the length and offset of each urb descriptor.
239 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
240 */
241 urb->iso_frame_desc[0].length = 4;
242 urb->iso_frame_desc[0].offset = 0;
243 cp[0] = ep->freqn;
244 cp[1] = ep->freqn >> 8;
245 cp[2] = ep->freqn >> 16;
246 cp[3] = ep->freqn >> 24;
247 } else {
248 /*
249 * fill the length and offset of each urb descriptor.
250 * the fixed 10.14 frequency is passed through the pipe.
251 */
252 urb->iso_frame_desc[0].length = 3;
253 urb->iso_frame_desc[0].offset = 0;
254 cp[0] = ep->freqn >> 2;
255 cp[1] = ep->freqn >> 10;
256 cp[2] = ep->freqn >> 18;
257 }
258
259 break;
260 }
261}
262
263/*
264 * Prepare a CAPTURE or SYNC urb for submission to the bus.
265 */
266static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep,
267 struct snd_urb_ctx *urb_ctx)
268{
269 int i, offs;
270 struct urb *urb = urb_ctx->urb;
271
272 urb->dev = ep->chip->dev; /* we need to set this at each time */
273
274 switch (ep->type) {
275 case SND_USB_ENDPOINT_TYPE_DATA:
276 offs = 0;
277 for (i = 0; i < urb_ctx->packets; i++) {
278 urb->iso_frame_desc[i].offset = offs;
279 urb->iso_frame_desc[i].length = ep->curpacksize;
280 offs += ep->curpacksize;
281 }
282
283 urb->transfer_buffer_length = offs;
284 urb->number_of_packets = urb_ctx->packets;
285 break;
286
287 case SND_USB_ENDPOINT_TYPE_SYNC:
288 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
289 urb->iso_frame_desc[0].offset = 0;
290 break;
291 }
292}
293
294/*
295 * Send output urbs that have been prepared previously. URBs are dequeued
296 * from ep->ready_playback_urbs and in case there there aren't any available
297 * or there are no packets that have been prepared, this function does
298 * nothing.
299 *
300 * The reason why the functionality of sending and preparing URBs is separated
301 * is that host controllers don't guarantee the order in which they return
302 * inbound and outbound packets to their submitters.
303 *
304 * This function is only used for implicit feedback endpoints. For endpoints
305 * driven by dedicated sync endpoints, URBs are immediately re-submitted
306 * from their completion handler.
307 */
308static void queue_pending_output_urbs(struct snd_usb_endpoint *ep)
309{
310 while (test_bit(EP_FLAG_RUNNING, &ep->flags)) {
311
312 unsigned long flags;
313 struct snd_usb_packet_info *uninitialized_var(packet);
314 struct snd_urb_ctx *ctx = NULL;
315 int err, i;
316
317 spin_lock_irqsave(&ep->lock, flags);
318 if (ep->next_packet_read_pos != ep->next_packet_write_pos) {
319 packet = ep->next_packet + ep->next_packet_read_pos;
320 ep->next_packet_read_pos++;
321 ep->next_packet_read_pos %= MAX_URBS;
322
323 /* take URB out of FIFO */
324 if (!list_empty(&ep->ready_playback_urbs))
325 ctx = list_first_entry(&ep->ready_playback_urbs,
326 struct snd_urb_ctx, ready_list);
327 }
328 spin_unlock_irqrestore(&ep->lock, flags);
329
330 if (ctx == NULL)
331 return;
332
333 list_del_init(&ctx->ready_list);
334
335 /* copy over the length information */
336 for (i = 0; i < packet->packets; i++)
337 ctx->packet_size[i] = packet->packet_size[i];
338
339 /* call the data handler to fill in playback data */
340 prepare_outbound_urb(ep, ctx);
341
342 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
343 if (err < 0)
344 usb_audio_err(ep->chip,
345 "Unable to submit urb #%d: %d (urb %p)\n",
346 ctx->index, err, ctx->urb);
347 else
348 set_bit(ctx->index, &ep->active_mask);
349 }
350}
351
352/*
353 * complete callback for urbs
354 */
355static void snd_complete_urb(struct urb *urb)
356{
357 struct snd_urb_ctx *ctx = urb->context;
358 struct snd_usb_endpoint *ep = ctx->ep;
359 struct snd_pcm_substream *substream;
360 unsigned long flags;
361 int err;
362
363 if (unlikely(urb->status == -ENOENT || /* unlinked */
364 urb->status == -ENODEV || /* device removed */
365 urb->status == -ECONNRESET || /* unlinked */
366 urb->status == -ESHUTDOWN)) /* device disabled */
367 goto exit_clear;
368 /* device disconnected */
369 if (unlikely(atomic_read(&ep->chip->shutdown)))
370 goto exit_clear;
371
372 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
373 goto exit_clear;
374
375 if (usb_pipeout(ep->pipe)) {
376 retire_outbound_urb(ep, ctx);
377 /* can be stopped during retire callback */
378 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
379 goto exit_clear;
380
381 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
382 spin_lock_irqsave(&ep->lock, flags);
383 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
384 spin_unlock_irqrestore(&ep->lock, flags);
385 queue_pending_output_urbs(ep);
386
387 goto exit_clear;
388 }
389
390 prepare_outbound_urb(ep, ctx);
391 /* can be stopped during prepare callback */
392 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
393 goto exit_clear;
394 } else {
395 retire_inbound_urb(ep, ctx);
396 /* can be stopped during retire callback */
397 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
398 goto exit_clear;
399
400 prepare_inbound_urb(ep, ctx);
401 }
402
403 err = usb_submit_urb(urb, GFP_ATOMIC);
404 if (err == 0)
405 return;
406
407 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
408 if (ep->data_subs && ep->data_subs->pcm_substream) {
409 substream = ep->data_subs->pcm_substream;
410 snd_pcm_stop_xrun(substream);
411 }
412
413exit_clear:
414 clear_bit(ctx->index, &ep->active_mask);
415}
416
417/**
418 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
419 *
420 * @chip: The chip
421 * @alts: The USB host interface
422 * @ep_num: The number of the endpoint to use
423 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
424 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
425 *
426 * If the requested endpoint has not been added to the given chip before,
427 * a new instance is created. Otherwise, a pointer to the previoulsy
428 * created instance is returned. In case of any error, NULL is returned.
429 *
430 * New endpoints will be added to chip->ep_list and must be freed by
431 * calling snd_usb_endpoint_free().
432 *
433 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
434 * bNumEndpoints > 1 beforehand.
435 */
436struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
437 struct usb_host_interface *alts,
438 int ep_num, int direction, int type)
439{
440 struct snd_usb_endpoint *ep;
441 int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK;
442
443 if (WARN_ON(!alts))
444 return NULL;
445
446 mutex_lock(&chip->mutex);
447
448 list_for_each_entry(ep, &chip->ep_list, list) {
449 if (ep->ep_num == ep_num &&
450 ep->iface == alts->desc.bInterfaceNumber &&
451 ep->altsetting == alts->desc.bAlternateSetting) {
452 usb_audio_dbg(ep->chip,
453 "Re-using EP %x in iface %d,%d @%p\n",
454 ep_num, ep->iface, ep->altsetting, ep);
455 goto __exit_unlock;
456 }
457 }
458
459 usb_audio_dbg(chip, "Creating new %s %s endpoint #%x\n",
460 is_playback ? "playback" : "capture",
461 type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync",
462 ep_num);
463
464 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
465 if (!ep)
466 goto __exit_unlock;
467
468 ep->chip = chip;
469 spin_lock_init(&ep->lock);
470 ep->type = type;
471 ep->ep_num = ep_num;
472 ep->iface = alts->desc.bInterfaceNumber;
473 ep->altsetting = alts->desc.bAlternateSetting;
474 INIT_LIST_HEAD(&ep->ready_playback_urbs);
475 ep_num &= USB_ENDPOINT_NUMBER_MASK;
476
477 if (is_playback)
478 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
479 else
480 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
481
482 if (type == SND_USB_ENDPOINT_TYPE_SYNC) {
483 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
484 get_endpoint(alts, 1)->bRefresh >= 1 &&
485 get_endpoint(alts, 1)->bRefresh <= 9)
486 ep->syncinterval = get_endpoint(alts, 1)->bRefresh;
487 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
488 ep->syncinterval = 1;
489 else if (get_endpoint(alts, 1)->bInterval >= 1 &&
490 get_endpoint(alts, 1)->bInterval <= 16)
491 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1;
492 else
493 ep->syncinterval = 3;
494
495 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize);
496 }
497
498 list_add_tail(&ep->list, &chip->ep_list);
499
500__exit_unlock:
501 mutex_unlock(&chip->mutex);
502
503 return ep;
504}
505
506/*
507 * wait until all urbs are processed.
508 */
509static int wait_clear_urbs(struct snd_usb_endpoint *ep)
510{
511 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
512 int alive;
513
514 do {
515 alive = bitmap_weight(&ep->active_mask, ep->nurbs);
516 if (!alive)
517 break;
518
519 schedule_timeout_uninterruptible(1);
520 } while (time_before(jiffies, end_time));
521
522 if (alive)
523 usb_audio_err(ep->chip,
524 "timeout: still %d active urbs on EP #%x\n",
525 alive, ep->ep_num);
526 clear_bit(EP_FLAG_STOPPING, &ep->flags);
527
528 ep->data_subs = NULL;
529 ep->sync_slave = NULL;
530 ep->retire_data_urb = NULL;
531 ep->prepare_data_urb = NULL;
532
533 return 0;
534}
535
536/* sync the pending stop operation;
537 * this function itself doesn't trigger the stop operation
538 */
539void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
540{
541 if (ep && test_bit(EP_FLAG_STOPPING, &ep->flags))
542 wait_clear_urbs(ep);
543}
544
545/*
546 * unlink active urbs.
547 */
548static int deactivate_urbs(struct snd_usb_endpoint *ep, bool force)
549{
550 unsigned int i;
551
552 if (!force && atomic_read(&ep->chip->shutdown)) /* to be sure... */
553 return -EBADFD;
554
555 clear_bit(EP_FLAG_RUNNING, &ep->flags);
556
557 INIT_LIST_HEAD(&ep->ready_playback_urbs);
558 ep->next_packet_read_pos = 0;
559 ep->next_packet_write_pos = 0;
560
561 for (i = 0; i < ep->nurbs; i++) {
562 if (test_bit(i, &ep->active_mask)) {
563 if (!test_and_set_bit(i, &ep->unlink_mask)) {
564 struct urb *u = ep->urb[i].urb;
565 usb_unlink_urb(u);
566 }
567 }
568 }
569
570 return 0;
571}
572
573/*
574 * release an endpoint's urbs
575 */
576static void release_urbs(struct snd_usb_endpoint *ep, int force)
577{
578 int i;
579
580 /* route incoming urbs to nirvana */
581 ep->retire_data_urb = NULL;
582 ep->prepare_data_urb = NULL;
583
584 /* stop urbs */
585 deactivate_urbs(ep, force);
586 wait_clear_urbs(ep);
587
588 for (i = 0; i < ep->nurbs; i++)
589 release_urb_ctx(&ep->urb[i]);
590
591 if (ep->syncbuf)
592 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
593 ep->syncbuf, ep->sync_dma);
594
595 ep->syncbuf = NULL;
596 ep->nurbs = 0;
597}
598
599/*
600 * configure a data endpoint
601 */
602static int data_ep_set_params(struct snd_usb_endpoint *ep,
603 snd_pcm_format_t pcm_format,
604 unsigned int channels,
605 unsigned int period_bytes,
606 unsigned int frames_per_period,
607 unsigned int periods_per_buffer,
608 struct audioformat *fmt,
609 struct snd_usb_endpoint *sync_ep)
610{
611 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
612 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
613 unsigned int max_urbs, i;
614 int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels;
615 int tx_length_quirk = (ep->chip->tx_length_quirk &&
616 usb_pipeout(ep->pipe));
617
618 if (pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
619 /*
620 * When operating in DSD DOP mode, the size of a sample frame
621 * in hardware differs from the actual physical format width
622 * because we need to make room for the DOP markers.
623 */
624 frame_bits += channels << 3;
625 }
626
627 ep->datainterval = fmt->datainterval;
628 ep->stride = frame_bits >> 3;
629
630 switch (pcm_format) {
631 case SNDRV_PCM_FORMAT_U8:
632 ep->silence_value = 0x80;
633 break;
634 case SNDRV_PCM_FORMAT_DSD_U8:
635 case SNDRV_PCM_FORMAT_DSD_U16_LE:
636 case SNDRV_PCM_FORMAT_DSD_U32_LE:
637 case SNDRV_PCM_FORMAT_DSD_U16_BE:
638 case SNDRV_PCM_FORMAT_DSD_U32_BE:
639 ep->silence_value = 0x69;
640 break;
641 default:
642 ep->silence_value = 0;
643 }
644
645 /* assume max. frequency is 50% higher than nominal */
646 ep->freqmax = ep->freqn + (ep->freqn >> 1);
647 /* Round up freqmax to nearest integer in order to calculate maximum
648 * packet size, which must represent a whole number of frames.
649 * This is accomplished by adding 0x0.ffff before converting the
650 * Q16.16 format into integer.
651 * In order to accurately calculate the maximum packet size when
652 * the data interval is more than 1 (i.e. ep->datainterval > 0),
653 * multiply by the data interval prior to rounding. For instance,
654 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
655 * frames with a data interval of 1, but 11 (10.25) frames with a
656 * data interval of 2.
657 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
658 * maximum datainterval value of 3, at USB full speed, higher for
659 * USB high speed, noting that ep->freqmax is in units of
660 * frames per packet in Q16.16 format.)
661 */
662 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
663 (frame_bits >> 3);
664 if (tx_length_quirk)
665 maxsize += sizeof(__le32); /* Space for length descriptor */
666 /* but wMaxPacketSize might reduce this */
667 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
668 /* whatever fits into a max. size packet */
669 unsigned int data_maxsize = maxsize = ep->maxpacksize;
670
671 if (tx_length_quirk)
672 /* Need to remove the length descriptor to calc freq */
673 data_maxsize -= sizeof(__le32);
674 ep->freqmax = (data_maxsize / (frame_bits >> 3))
675 << (16 - ep->datainterval);
676 }
677
678 if (ep->fill_max)
679 ep->curpacksize = ep->maxpacksize;
680 else
681 ep->curpacksize = maxsize;
682
683 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) {
684 packs_per_ms = 8 >> ep->datainterval;
685 max_packs_per_urb = MAX_PACKS_HS;
686 } else {
687 packs_per_ms = 1;
688 max_packs_per_urb = MAX_PACKS;
689 }
690 if (sync_ep && !snd_usb_endpoint_implicit_feedback_sink(ep))
691 max_packs_per_urb = min(max_packs_per_urb,
692 1U << sync_ep->syncinterval);
693 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
694
695 /*
696 * Capture endpoints need to use small URBs because there's no way
697 * to tell in advance where the next period will end, and we don't
698 * want the next URB to complete much after the period ends.
699 *
700 * Playback endpoints with implicit sync much use the same parameters
701 * as their corresponding capture endpoint.
702 */
703 if (usb_pipein(ep->pipe) ||
704 snd_usb_endpoint_implicit_feedback_sink(ep)) {
705
706 urb_packs = packs_per_ms;
707 /*
708 * Wireless devices can poll at a max rate of once per 4ms.
709 * For dataintervals less than 5, increase the packet count to
710 * allow the host controller to use bursting to fill in the
711 * gaps.
712 */
713 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_WIRELESS) {
714 int interval = ep->datainterval;
715 while (interval < 5) {
716 urb_packs <<= 1;
717 ++interval;
718 }
719 }
720 /* make capture URBs <= 1 ms and smaller than a period */
721 urb_packs = min(max_packs_per_urb, urb_packs);
722 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
723 urb_packs >>= 1;
724 ep->nurbs = MAX_URBS;
725
726 /*
727 * Playback endpoints without implicit sync are adjusted so that
728 * a period fits as evenly as possible in the smallest number of
729 * URBs. The total number of URBs is adjusted to the size of the
730 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
731 */
732 } else {
733 /* determine how small a packet can be */
734 minsize = (ep->freqn >> (16 - ep->datainterval)) *
735 (frame_bits >> 3);
736 /* with sync from device, assume it can be 12% lower */
737 if (sync_ep)
738 minsize -= minsize >> 3;
739 minsize = max(minsize, 1u);
740
741 /* how many packets will contain an entire ALSA period? */
742 max_packs_per_period = DIV_ROUND_UP(period_bytes, minsize);
743
744 /* how many URBs will contain a period? */
745 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
746 max_packs_per_urb);
747 /* how many packets are needed in each URB? */
748 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
749
750 /* limit the number of frames in a single URB */
751 ep->max_urb_frames = DIV_ROUND_UP(frames_per_period,
752 urbs_per_period);
753
754 /* try to use enough URBs to contain an entire ALSA buffer */
755 max_urbs = min((unsigned) MAX_URBS,
756 MAX_QUEUE * packs_per_ms / urb_packs);
757 ep->nurbs = min(max_urbs, urbs_per_period * periods_per_buffer);
758 }
759
760 /* allocate and initialize data urbs */
761 for (i = 0; i < ep->nurbs; i++) {
762 struct snd_urb_ctx *u = &ep->urb[i];
763 u->index = i;
764 u->ep = ep;
765 u->packets = urb_packs;
766 u->buffer_size = maxsize * u->packets;
767
768 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
769 u->packets++; /* for transfer delimiter */
770 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
771 if (!u->urb)
772 goto out_of_memory;
773
774 u->urb->transfer_buffer =
775 usb_alloc_coherent(ep->chip->dev, u->buffer_size,
776 GFP_KERNEL, &u->urb->transfer_dma);
777 if (!u->urb->transfer_buffer)
778 goto out_of_memory;
779 u->urb->pipe = ep->pipe;
780 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
781 u->urb->interval = 1 << ep->datainterval;
782 u->urb->context = u;
783 u->urb->complete = snd_complete_urb;
784 INIT_LIST_HEAD(&u->ready_list);
785 }
786
787 return 0;
788
789out_of_memory:
790 release_urbs(ep, 0);
791 return -ENOMEM;
792}
793
794/*
795 * configure a sync endpoint
796 */
797static int sync_ep_set_params(struct snd_usb_endpoint *ep)
798{
799 int i;
800
801 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4,
802 GFP_KERNEL, &ep->sync_dma);
803 if (!ep->syncbuf)
804 return -ENOMEM;
805
806 for (i = 0; i < SYNC_URBS; i++) {
807 struct snd_urb_ctx *u = &ep->urb[i];
808 u->index = i;
809 u->ep = ep;
810 u->packets = 1;
811 u->urb = usb_alloc_urb(1, GFP_KERNEL);
812 if (!u->urb)
813 goto out_of_memory;
814 u->urb->transfer_buffer = ep->syncbuf + i * 4;
815 u->urb->transfer_dma = ep->sync_dma + i * 4;
816 u->urb->transfer_buffer_length = 4;
817 u->urb->pipe = ep->pipe;
818 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
819 u->urb->number_of_packets = 1;
820 u->urb->interval = 1 << ep->syncinterval;
821 u->urb->context = u;
822 u->urb->complete = snd_complete_urb;
823 }
824
825 ep->nurbs = SYNC_URBS;
826
827 return 0;
828
829out_of_memory:
830 release_urbs(ep, 0);
831 return -ENOMEM;
832}
833
834/**
835 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
836 *
837 * @ep: the snd_usb_endpoint to configure
838 * @pcm_format: the audio fomat.
839 * @channels: the number of audio channels.
840 * @period_bytes: the number of bytes in one alsa period.
841 * @period_frames: the number of frames in one alsa period.
842 * @buffer_periods: the number of periods in one alsa buffer.
843 * @rate: the frame rate.
844 * @fmt: the USB audio format information
845 * @sync_ep: the sync endpoint to use, if any
846 *
847 * Determine the number of URBs to be used on this endpoint.
848 * An endpoint must be configured before it can be started.
849 * An endpoint that is already running can not be reconfigured.
850 */
851int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
852 snd_pcm_format_t pcm_format,
853 unsigned int channels,
854 unsigned int period_bytes,
855 unsigned int period_frames,
856 unsigned int buffer_periods,
857 unsigned int rate,
858 struct audioformat *fmt,
859 struct snd_usb_endpoint *sync_ep)
860{
861 int err;
862
863 if (ep->use_count != 0) {
864 usb_audio_warn(ep->chip,
865 "Unable to change format on ep #%x: already in use\n",
866 ep->ep_num);
867 return -EBUSY;
868 }
869
870 /* release old buffers, if any */
871 release_urbs(ep, 0);
872
873 ep->datainterval = fmt->datainterval;
874 ep->maxpacksize = fmt->maxpacksize;
875 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
876
877 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL)
878 ep->freqn = get_usb_full_speed_rate(rate);
879 else
880 ep->freqn = get_usb_high_speed_rate(rate);
881
882 /* calculate the frequency in 16.16 format */
883 ep->freqm = ep->freqn;
884 ep->freqshift = INT_MIN;
885
886 ep->phase = 0;
887
888 switch (ep->type) {
889 case SND_USB_ENDPOINT_TYPE_DATA:
890 err = data_ep_set_params(ep, pcm_format, channels,
891 period_bytes, period_frames,
892 buffer_periods, fmt, sync_ep);
893 break;
894 case SND_USB_ENDPOINT_TYPE_SYNC:
895 err = sync_ep_set_params(ep);
896 break;
897 default:
898 err = -EINVAL;
899 }
900
901 usb_audio_dbg(ep->chip,
902 "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
903 ep->ep_num, ep->type, ep->nurbs, err);
904
905 return err;
906}
907
908/**
909 * snd_usb_endpoint_start: start an snd_usb_endpoint
910 *
911 * @ep: the endpoint to start
912 *
913 * A call to this function will increment the use count of the endpoint.
914 * In case it is not already running, the URBs for this endpoint will be
915 * submitted. Otherwise, this function does nothing.
916 *
917 * Must be balanced to calls of snd_usb_endpoint_stop().
918 *
919 * Returns an error if the URB submission failed, 0 in all other cases.
920 */
921int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
922{
923 int err;
924 unsigned int i;
925
926 if (atomic_read(&ep->chip->shutdown))
927 return -EBADFD;
928
929 /* already running? */
930 if (++ep->use_count != 1)
931 return 0;
932
933 /* just to be sure */
934 deactivate_urbs(ep, false);
935
936 ep->active_mask = 0;
937 ep->unlink_mask = 0;
938 ep->phase = 0;
939
940 snd_usb_endpoint_start_quirk(ep);
941
942 /*
943 * If this endpoint has a data endpoint as implicit feedback source,
944 * don't start the urbs here. Instead, mark them all as available,
945 * wait for the record urbs to return and queue the playback urbs
946 * from that context.
947 */
948
949 set_bit(EP_FLAG_RUNNING, &ep->flags);
950
951 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
952 for (i = 0; i < ep->nurbs; i++) {
953 struct snd_urb_ctx *ctx = ep->urb + i;
954 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
955 }
956
957 return 0;
958 }
959
960 for (i = 0; i < ep->nurbs; i++) {
961 struct urb *urb = ep->urb[i].urb;
962
963 if (snd_BUG_ON(!urb))
964 goto __error;
965
966 if (usb_pipeout(ep->pipe)) {
967 prepare_outbound_urb(ep, urb->context);
968 } else {
969 prepare_inbound_urb(ep, urb->context);
970 }
971
972 err = usb_submit_urb(urb, GFP_ATOMIC);
973 if (err < 0) {
974 usb_audio_err(ep->chip,
975 "cannot submit urb %d, error %d: %s\n",
976 i, err, usb_error_string(err));
977 goto __error;
978 }
979 set_bit(i, &ep->active_mask);
980 }
981
982 return 0;
983
984__error:
985 clear_bit(EP_FLAG_RUNNING, &ep->flags);
986 ep->use_count--;
987 deactivate_urbs(ep, false);
988 return -EPIPE;
989}
990
991/**
992 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
993 *
994 * @ep: the endpoint to stop (may be NULL)
995 *
996 * A call to this function will decrement the use count of the endpoint.
997 * In case the last user has requested the endpoint stop, the URBs will
998 * actually be deactivated.
999 *
1000 * Must be balanced to calls of snd_usb_endpoint_start().
1001 *
1002 * The caller needs to synchronize the pending stop operation via
1003 * snd_usb_endpoint_sync_pending_stop().
1004 */
1005void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep)
1006{
1007 if (!ep)
1008 return;
1009
1010 if (snd_BUG_ON(ep->use_count == 0))
1011 return;
1012
1013 if (--ep->use_count == 0) {
1014 deactivate_urbs(ep, false);
1015 set_bit(EP_FLAG_STOPPING, &ep->flags);
1016 }
1017}
1018
1019/**
1020 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
1021 *
1022 * @ep: the endpoint to deactivate
1023 *
1024 * If the endpoint is not currently in use, this functions will
1025 * deactivate its associated URBs.
1026 *
1027 * In case of any active users, this functions does nothing.
1028 */
1029void snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep)
1030{
1031 if (!ep)
1032 return;
1033
1034 if (ep->use_count != 0)
1035 return;
1036
1037 deactivate_urbs(ep, true);
1038 wait_clear_urbs(ep);
1039}
1040
1041/**
1042 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1043 *
1044 * @ep: the endpoint to release
1045 *
1046 * This function does not care for the endpoint's use count but will tear
1047 * down all the streaming URBs immediately.
1048 */
1049void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1050{
1051 release_urbs(ep, 1);
1052}
1053
1054/**
1055 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
1056 *
1057 * @ep: the endpoint to free
1058 *
1059 * This free all resources of the given ep.
1060 */
1061void snd_usb_endpoint_free(struct snd_usb_endpoint *ep)
1062{
1063 kfree(ep);
1064}
1065
1066/**
1067 * snd_usb_handle_sync_urb: parse an USB sync packet
1068 *
1069 * @ep: the endpoint to handle the packet
1070 * @sender: the sending endpoint
1071 * @urb: the received packet
1072 *
1073 * This function is called from the context of an endpoint that received
1074 * the packet and is used to let another endpoint object handle the payload.
1075 */
1076void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1077 struct snd_usb_endpoint *sender,
1078 const struct urb *urb)
1079{
1080 int shift;
1081 unsigned int f;
1082 unsigned long flags;
1083
1084 snd_BUG_ON(ep == sender);
1085
1086 /*
1087 * In case the endpoint is operating in implicit feedback mode, prepare
1088 * a new outbound URB that has the same layout as the received packet
1089 * and add it to the list of pending urbs. queue_pending_output_urbs()
1090 * will take care of them later.
1091 */
1092 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1093 ep->use_count != 0) {
1094
1095 /* implicit feedback case */
1096 int i, bytes = 0;
1097 struct snd_urb_ctx *in_ctx;
1098 struct snd_usb_packet_info *out_packet;
1099
1100 in_ctx = urb->context;
1101
1102 /* Count overall packet size */
1103 for (i = 0; i < in_ctx->packets; i++)
1104 if (urb->iso_frame_desc[i].status == 0)
1105 bytes += urb->iso_frame_desc[i].actual_length;
1106
1107 /*
1108 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1109 * streaming once it received a 0-byte OUT URB
1110 */
1111 if (bytes == 0)
1112 return;
1113
1114 spin_lock_irqsave(&ep->lock, flags);
1115 out_packet = ep->next_packet + ep->next_packet_write_pos;
1116
1117 /*
1118 * Iterate through the inbound packet and prepare the lengths
1119 * for the output packet. The OUT packet we are about to send
1120 * will have the same amount of payload bytes per stride as the
1121 * IN packet we just received. Since the actual size is scaled
1122 * by the stride, use the sender stride to calculate the length
1123 * in case the number of channels differ between the implicitly
1124 * fed-back endpoint and the synchronizing endpoint.
1125 */
1126
1127 out_packet->packets = in_ctx->packets;
1128 for (i = 0; i < in_ctx->packets; i++) {
1129 if (urb->iso_frame_desc[i].status == 0)
1130 out_packet->packet_size[i] =
1131 urb->iso_frame_desc[i].actual_length / sender->stride;
1132 else
1133 out_packet->packet_size[i] = 0;
1134 }
1135
1136 ep->next_packet_write_pos++;
1137 ep->next_packet_write_pos %= MAX_URBS;
1138 spin_unlock_irqrestore(&ep->lock, flags);
1139 queue_pending_output_urbs(ep);
1140
1141 return;
1142 }
1143
1144 /*
1145 * process after playback sync complete
1146 *
1147 * Full speed devices report feedback values in 10.14 format as samples
1148 * per frame, high speed devices in 16.16 format as samples per
1149 * microframe.
1150 *
1151 * Because the Audio Class 1 spec was written before USB 2.0, many high
1152 * speed devices use a wrong interpretation, some others use an
1153 * entirely different format.
1154 *
1155 * Therefore, we cannot predict what format any particular device uses
1156 * and must detect it automatically.
1157 */
1158
1159 if (urb->iso_frame_desc[0].status != 0 ||
1160 urb->iso_frame_desc[0].actual_length < 3)
1161 return;
1162
1163 f = le32_to_cpup(urb->transfer_buffer);
1164 if (urb->iso_frame_desc[0].actual_length == 3)
1165 f &= 0x00ffffff;
1166 else
1167 f &= 0x0fffffff;
1168
1169 if (f == 0)
1170 return;
1171
1172 if (unlikely(sender->tenor_fb_quirk)) {
1173 /*
1174 * Devices based on Tenor 8802 chipsets (TEAC UD-H01
1175 * and others) sometimes change the feedback value
1176 * by +/- 0x1.0000.
1177 */
1178 if (f < ep->freqn - 0x8000)
1179 f += 0xf000;
1180 else if (f > ep->freqn + 0x8000)
1181 f -= 0xf000;
1182 } else if (unlikely(ep->freqshift == INT_MIN)) {
1183 /*
1184 * The first time we see a feedback value, determine its format
1185 * by shifting it left or right until it matches the nominal
1186 * frequency value. This assumes that the feedback does not
1187 * differ from the nominal value more than +50% or -25%.
1188 */
1189 shift = 0;
1190 while (f < ep->freqn - ep->freqn / 4) {
1191 f <<= 1;
1192 shift++;
1193 }
1194 while (f > ep->freqn + ep->freqn / 2) {
1195 f >>= 1;
1196 shift--;
1197 }
1198 ep->freqshift = shift;
1199 } else if (ep->freqshift >= 0)
1200 f <<= ep->freqshift;
1201 else
1202 f >>= -ep->freqshift;
1203
1204 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1205 /*
1206 * If the frequency looks valid, set it.
1207 * This value is referred to in prepare_playback_urb().
1208 */
1209 spin_lock_irqsave(&ep->lock, flags);
1210 ep->freqm = f;
1211 spin_unlock_irqrestore(&ep->lock, flags);
1212 } else {
1213 /*
1214 * Out of range; maybe the shift value is wrong.
1215 * Reset it so that we autodetect again the next time.
1216 */
1217 ep->freqshift = INT_MIN;
1218 }
1219}
1220
1/*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
6 *
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
15 *
16 */
17
18#include <linux/gfp.h>
19#include <linux/init.h>
20#include <linux/ratelimit.h>
21#include <linux/usb.h>
22#include <linux/usb/audio.h>
23#include <linux/slab.h>
24
25#include <sound/core.h>
26#include <sound/pcm.h>
27#include <sound/pcm_params.h>
28
29#include "usbaudio.h"
30#include "helper.h"
31#include "card.h"
32#include "endpoint.h"
33#include "pcm.h"
34#include "quirks.h"
35
36#define EP_FLAG_RUNNING 1
37#define EP_FLAG_STOPPING 2
38
39/*
40 * snd_usb_endpoint is a model that abstracts everything related to an
41 * USB endpoint and its streaming.
42 *
43 * There are functions to activate and deactivate the streaming URBs and
44 * optional callbacks to let the pcm logic handle the actual content of the
45 * packets for playback and record. Thus, the bus streaming and the audio
46 * handlers are fully decoupled.
47 *
48 * There are two different types of endpoints in audio applications.
49 *
50 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
51 * inbound and outbound traffic.
52 *
53 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
54 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
55 * (3 or 4 bytes).
56 *
57 * Each endpoint has to be configured prior to being used by calling
58 * snd_usb_endpoint_set_params().
59 *
60 * The model incorporates a reference counting, so that multiple users
61 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
62 * only the first user will effectively start the URBs, and only the last
63 * one to stop it will tear the URBs down again.
64 */
65
66/*
67 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
68 * this will overflow at approx 524 kHz
69 */
70static inline unsigned get_usb_full_speed_rate(unsigned int rate)
71{
72 return ((rate << 13) + 62) / 125;
73}
74
75/*
76 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
77 * this will overflow at approx 4 MHz
78 */
79static inline unsigned get_usb_high_speed_rate(unsigned int rate)
80{
81 return ((rate << 10) + 62) / 125;
82}
83
84/*
85 * release a urb data
86 */
87static void release_urb_ctx(struct snd_urb_ctx *u)
88{
89 if (u->buffer_size)
90 usb_free_coherent(u->ep->chip->dev, u->buffer_size,
91 u->urb->transfer_buffer,
92 u->urb->transfer_dma);
93 usb_free_urb(u->urb);
94 u->urb = NULL;
95}
96
97static const char *usb_error_string(int err)
98{
99 switch (err) {
100 case -ENODEV:
101 return "no device";
102 case -ENOENT:
103 return "endpoint not enabled";
104 case -EPIPE:
105 return "endpoint stalled";
106 case -ENOSPC:
107 return "not enough bandwidth";
108 case -ESHUTDOWN:
109 return "device disabled";
110 case -EHOSTUNREACH:
111 return "device suspended";
112 case -EINVAL:
113 case -EAGAIN:
114 case -EFBIG:
115 case -EMSGSIZE:
116 return "internal error";
117 default:
118 return "unknown error";
119 }
120}
121
122/**
123 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
124 *
125 * @ep: The snd_usb_endpoint
126 *
127 * Determine whether an endpoint is driven by an implicit feedback
128 * data endpoint source.
129 */
130int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
131{
132 return ep->sync_master &&
133 ep->sync_master->type == SND_USB_ENDPOINT_TYPE_DATA &&
134 ep->type == SND_USB_ENDPOINT_TYPE_DATA &&
135 usb_pipeout(ep->pipe);
136}
137
138/*
139 * For streaming based on information derived from sync endpoints,
140 * prepare_outbound_urb_sizes() will call next_packet_size() to
141 * determine the number of samples to be sent in the next packet.
142 *
143 * For implicit feedback, next_packet_size() is unused.
144 */
145int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep)
146{
147 unsigned long flags;
148 int ret;
149
150 if (ep->fill_max)
151 return ep->maxframesize;
152
153 spin_lock_irqsave(&ep->lock, flags);
154 ep->phase = (ep->phase & 0xffff)
155 + (ep->freqm << ep->datainterval);
156 ret = min(ep->phase >> 16, ep->maxframesize);
157 spin_unlock_irqrestore(&ep->lock, flags);
158
159 return ret;
160}
161
162static void retire_outbound_urb(struct snd_usb_endpoint *ep,
163 struct snd_urb_ctx *urb_ctx)
164{
165 if (ep->retire_data_urb)
166 ep->retire_data_urb(ep->data_subs, urb_ctx->urb);
167}
168
169static void retire_inbound_urb(struct snd_usb_endpoint *ep,
170 struct snd_urb_ctx *urb_ctx)
171{
172 struct urb *urb = urb_ctx->urb;
173
174 if (unlikely(ep->skip_packets > 0)) {
175 ep->skip_packets--;
176 return;
177 }
178
179 if (ep->sync_slave)
180 snd_usb_handle_sync_urb(ep->sync_slave, ep, urb);
181
182 if (ep->retire_data_urb)
183 ep->retire_data_urb(ep->data_subs, urb);
184}
185
186/*
187 * Prepare a PLAYBACK urb for submission to the bus.
188 */
189static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
190 struct snd_urb_ctx *ctx)
191{
192 int i;
193 struct urb *urb = ctx->urb;
194 unsigned char *cp = urb->transfer_buffer;
195
196 urb->dev = ep->chip->dev; /* we need to set this at each time */
197
198 switch (ep->type) {
199 case SND_USB_ENDPOINT_TYPE_DATA:
200 if (ep->prepare_data_urb) {
201 ep->prepare_data_urb(ep->data_subs, urb);
202 } else {
203 /* no data provider, so send silence */
204 unsigned int offs = 0;
205 for (i = 0; i < ctx->packets; ++i) {
206 int counts;
207
208 if (ctx->packet_size[i])
209 counts = ctx->packet_size[i];
210 else
211 counts = snd_usb_endpoint_next_packet_size(ep);
212
213 urb->iso_frame_desc[i].offset = offs * ep->stride;
214 urb->iso_frame_desc[i].length = counts * ep->stride;
215 offs += counts;
216 }
217
218 urb->number_of_packets = ctx->packets;
219 urb->transfer_buffer_length = offs * ep->stride;
220 memset(urb->transfer_buffer, ep->silence_value,
221 offs * ep->stride);
222 }
223 break;
224
225 case SND_USB_ENDPOINT_TYPE_SYNC:
226 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
227 /*
228 * fill the length and offset of each urb descriptor.
229 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
230 */
231 urb->iso_frame_desc[0].length = 4;
232 urb->iso_frame_desc[0].offset = 0;
233 cp[0] = ep->freqn;
234 cp[1] = ep->freqn >> 8;
235 cp[2] = ep->freqn >> 16;
236 cp[3] = ep->freqn >> 24;
237 } else {
238 /*
239 * fill the length and offset of each urb descriptor.
240 * the fixed 10.14 frequency is passed through the pipe.
241 */
242 urb->iso_frame_desc[0].length = 3;
243 urb->iso_frame_desc[0].offset = 0;
244 cp[0] = ep->freqn >> 2;
245 cp[1] = ep->freqn >> 10;
246 cp[2] = ep->freqn >> 18;
247 }
248
249 break;
250 }
251}
252
253/*
254 * Prepare a CAPTURE or SYNC urb for submission to the bus.
255 */
256static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep,
257 struct snd_urb_ctx *urb_ctx)
258{
259 int i, offs;
260 struct urb *urb = urb_ctx->urb;
261
262 urb->dev = ep->chip->dev; /* we need to set this at each time */
263
264 switch (ep->type) {
265 case SND_USB_ENDPOINT_TYPE_DATA:
266 offs = 0;
267 for (i = 0; i < urb_ctx->packets; i++) {
268 urb->iso_frame_desc[i].offset = offs;
269 urb->iso_frame_desc[i].length = ep->curpacksize;
270 offs += ep->curpacksize;
271 }
272
273 urb->transfer_buffer_length = offs;
274 urb->number_of_packets = urb_ctx->packets;
275 break;
276
277 case SND_USB_ENDPOINT_TYPE_SYNC:
278 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
279 urb->iso_frame_desc[0].offset = 0;
280 break;
281 }
282}
283
284/*
285 * Send output urbs that have been prepared previously. URBs are dequeued
286 * from ep->ready_playback_urbs and in case there there aren't any available
287 * or there are no packets that have been prepared, this function does
288 * nothing.
289 *
290 * The reason why the functionality of sending and preparing URBs is separated
291 * is that host controllers don't guarantee the order in which they return
292 * inbound and outbound packets to their submitters.
293 *
294 * This function is only used for implicit feedback endpoints. For endpoints
295 * driven by dedicated sync endpoints, URBs are immediately re-submitted
296 * from their completion handler.
297 */
298static void queue_pending_output_urbs(struct snd_usb_endpoint *ep)
299{
300 while (test_bit(EP_FLAG_RUNNING, &ep->flags)) {
301
302 unsigned long flags;
303 struct snd_usb_packet_info *uninitialized_var(packet);
304 struct snd_urb_ctx *ctx = NULL;
305 struct urb *urb;
306 int err, i;
307
308 spin_lock_irqsave(&ep->lock, flags);
309 if (ep->next_packet_read_pos != ep->next_packet_write_pos) {
310 packet = ep->next_packet + ep->next_packet_read_pos;
311 ep->next_packet_read_pos++;
312 ep->next_packet_read_pos %= MAX_URBS;
313
314 /* take URB out of FIFO */
315 if (!list_empty(&ep->ready_playback_urbs))
316 ctx = list_first_entry(&ep->ready_playback_urbs,
317 struct snd_urb_ctx, ready_list);
318 }
319 spin_unlock_irqrestore(&ep->lock, flags);
320
321 if (ctx == NULL)
322 return;
323
324 list_del_init(&ctx->ready_list);
325 urb = ctx->urb;
326
327 /* copy over the length information */
328 for (i = 0; i < packet->packets; i++)
329 ctx->packet_size[i] = packet->packet_size[i];
330
331 /* call the data handler to fill in playback data */
332 prepare_outbound_urb(ep, ctx);
333
334 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
335 if (err < 0)
336 usb_audio_err(ep->chip,
337 "Unable to submit urb #%d: %d (urb %p)\n",
338 ctx->index, err, ctx->urb);
339 else
340 set_bit(ctx->index, &ep->active_mask);
341 }
342}
343
344/*
345 * complete callback for urbs
346 */
347static void snd_complete_urb(struct urb *urb)
348{
349 struct snd_urb_ctx *ctx = urb->context;
350 struct snd_usb_endpoint *ep = ctx->ep;
351 int err;
352
353 if (unlikely(urb->status == -ENOENT || /* unlinked */
354 urb->status == -ENODEV || /* device removed */
355 urb->status == -ECONNRESET || /* unlinked */
356 urb->status == -ESHUTDOWN || /* device disabled */
357 ep->chip->shutdown)) /* device disconnected */
358 goto exit_clear;
359
360 if (usb_pipeout(ep->pipe)) {
361 retire_outbound_urb(ep, ctx);
362 /* can be stopped during retire callback */
363 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
364 goto exit_clear;
365
366 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
367 unsigned long flags;
368
369 spin_lock_irqsave(&ep->lock, flags);
370 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
371 spin_unlock_irqrestore(&ep->lock, flags);
372 queue_pending_output_urbs(ep);
373
374 goto exit_clear;
375 }
376
377 prepare_outbound_urb(ep, ctx);
378 } else {
379 retire_inbound_urb(ep, ctx);
380 /* can be stopped during retire callback */
381 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
382 goto exit_clear;
383
384 prepare_inbound_urb(ep, ctx);
385 }
386
387 err = usb_submit_urb(urb, GFP_ATOMIC);
388 if (err == 0)
389 return;
390
391 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
392 //snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
393
394exit_clear:
395 clear_bit(ctx->index, &ep->active_mask);
396}
397
398/**
399 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
400 *
401 * @chip: The chip
402 * @alts: The USB host interface
403 * @ep_num: The number of the endpoint to use
404 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
405 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
406 *
407 * If the requested endpoint has not been added to the given chip before,
408 * a new instance is created. Otherwise, a pointer to the previoulsy
409 * created instance is returned. In case of any error, NULL is returned.
410 *
411 * New endpoints will be added to chip->ep_list and must be freed by
412 * calling snd_usb_endpoint_free().
413 */
414struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
415 struct usb_host_interface *alts,
416 int ep_num, int direction, int type)
417{
418 struct snd_usb_endpoint *ep;
419 int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK;
420
421 if (WARN_ON(!alts))
422 return NULL;
423
424 mutex_lock(&chip->mutex);
425
426 list_for_each_entry(ep, &chip->ep_list, list) {
427 if (ep->ep_num == ep_num &&
428 ep->iface == alts->desc.bInterfaceNumber &&
429 ep->altsetting == alts->desc.bAlternateSetting) {
430 usb_audio_dbg(ep->chip,
431 "Re-using EP %x in iface %d,%d @%p\n",
432 ep_num, ep->iface, ep->altsetting, ep);
433 goto __exit_unlock;
434 }
435 }
436
437 usb_audio_dbg(chip, "Creating new %s %s endpoint #%x\n",
438 is_playback ? "playback" : "capture",
439 type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync",
440 ep_num);
441
442 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
443 if (!ep)
444 goto __exit_unlock;
445
446 ep->chip = chip;
447 spin_lock_init(&ep->lock);
448 ep->type = type;
449 ep->ep_num = ep_num;
450 ep->iface = alts->desc.bInterfaceNumber;
451 ep->altsetting = alts->desc.bAlternateSetting;
452 INIT_LIST_HEAD(&ep->ready_playback_urbs);
453 ep_num &= USB_ENDPOINT_NUMBER_MASK;
454
455 if (is_playback)
456 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
457 else
458 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
459
460 if (type == SND_USB_ENDPOINT_TYPE_SYNC) {
461 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
462 get_endpoint(alts, 1)->bRefresh >= 1 &&
463 get_endpoint(alts, 1)->bRefresh <= 9)
464 ep->syncinterval = get_endpoint(alts, 1)->bRefresh;
465 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
466 ep->syncinterval = 1;
467 else if (get_endpoint(alts, 1)->bInterval >= 1 &&
468 get_endpoint(alts, 1)->bInterval <= 16)
469 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1;
470 else
471 ep->syncinterval = 3;
472
473 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize);
474
475 if (chip->usb_id == USB_ID(0x0644, 0x8038) /* TEAC UD-H01 */ &&
476 ep->syncmaxsize == 4)
477 ep->udh01_fb_quirk = 1;
478 }
479
480 list_add_tail(&ep->list, &chip->ep_list);
481
482__exit_unlock:
483 mutex_unlock(&chip->mutex);
484
485 return ep;
486}
487
488/*
489 * wait until all urbs are processed.
490 */
491static int wait_clear_urbs(struct snd_usb_endpoint *ep)
492{
493 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
494 int alive;
495
496 do {
497 alive = bitmap_weight(&ep->active_mask, ep->nurbs);
498 if (!alive)
499 break;
500
501 schedule_timeout_uninterruptible(1);
502 } while (time_before(jiffies, end_time));
503
504 if (alive)
505 usb_audio_err(ep->chip,
506 "timeout: still %d active urbs on EP #%x\n",
507 alive, ep->ep_num);
508 clear_bit(EP_FLAG_STOPPING, &ep->flags);
509
510 return 0;
511}
512
513/* sync the pending stop operation;
514 * this function itself doesn't trigger the stop operation
515 */
516void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
517{
518 if (ep && test_bit(EP_FLAG_STOPPING, &ep->flags))
519 wait_clear_urbs(ep);
520}
521
522/*
523 * unlink active urbs.
524 */
525static int deactivate_urbs(struct snd_usb_endpoint *ep, bool force)
526{
527 unsigned int i;
528
529 if (!force && ep->chip->shutdown) /* to be sure... */
530 return -EBADFD;
531
532 clear_bit(EP_FLAG_RUNNING, &ep->flags);
533
534 INIT_LIST_HEAD(&ep->ready_playback_urbs);
535 ep->next_packet_read_pos = 0;
536 ep->next_packet_write_pos = 0;
537
538 for (i = 0; i < ep->nurbs; i++) {
539 if (test_bit(i, &ep->active_mask)) {
540 if (!test_and_set_bit(i, &ep->unlink_mask)) {
541 struct urb *u = ep->urb[i].urb;
542 usb_unlink_urb(u);
543 }
544 }
545 }
546
547 return 0;
548}
549
550/*
551 * release an endpoint's urbs
552 */
553static void release_urbs(struct snd_usb_endpoint *ep, int force)
554{
555 int i;
556
557 /* route incoming urbs to nirvana */
558 ep->retire_data_urb = NULL;
559 ep->prepare_data_urb = NULL;
560
561 /* stop urbs */
562 deactivate_urbs(ep, force);
563 wait_clear_urbs(ep);
564
565 for (i = 0; i < ep->nurbs; i++)
566 release_urb_ctx(&ep->urb[i]);
567
568 if (ep->syncbuf)
569 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
570 ep->syncbuf, ep->sync_dma);
571
572 ep->syncbuf = NULL;
573 ep->nurbs = 0;
574}
575
576/*
577 * configure a data endpoint
578 */
579static int data_ep_set_params(struct snd_usb_endpoint *ep,
580 snd_pcm_format_t pcm_format,
581 unsigned int channels,
582 unsigned int period_bytes,
583 unsigned int frames_per_period,
584 unsigned int periods_per_buffer,
585 struct audioformat *fmt,
586 struct snd_usb_endpoint *sync_ep)
587{
588 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
589 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
590 unsigned int max_urbs, i;
591 int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels;
592
593 if (pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
594 /*
595 * When operating in DSD DOP mode, the size of a sample frame
596 * in hardware differs from the actual physical format width
597 * because we need to make room for the DOP markers.
598 */
599 frame_bits += channels << 3;
600 }
601
602 ep->datainterval = fmt->datainterval;
603 ep->stride = frame_bits >> 3;
604 ep->silence_value = pcm_format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0;
605
606 /* assume max. frequency is 25% higher than nominal */
607 ep->freqmax = ep->freqn + (ep->freqn >> 2);
608 maxsize = ((ep->freqmax + 0xffff) * (frame_bits >> 3))
609 >> (16 - ep->datainterval);
610 /* but wMaxPacketSize might reduce this */
611 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
612 /* whatever fits into a max. size packet */
613 maxsize = ep->maxpacksize;
614 ep->freqmax = (maxsize / (frame_bits >> 3))
615 << (16 - ep->datainterval);
616 }
617
618 if (ep->fill_max)
619 ep->curpacksize = ep->maxpacksize;
620 else
621 ep->curpacksize = maxsize;
622
623 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) {
624 packs_per_ms = 8 >> ep->datainterval;
625 max_packs_per_urb = MAX_PACKS_HS;
626 } else {
627 packs_per_ms = 1;
628 max_packs_per_urb = MAX_PACKS;
629 }
630 if (sync_ep && !snd_usb_endpoint_implicit_feedback_sink(ep))
631 max_packs_per_urb = min(max_packs_per_urb,
632 1U << sync_ep->syncinterval);
633 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
634
635 /*
636 * Capture endpoints need to use small URBs because there's no way
637 * to tell in advance where the next period will end, and we don't
638 * want the next URB to complete much after the period ends.
639 *
640 * Playback endpoints with implicit sync much use the same parameters
641 * as their corresponding capture endpoint.
642 */
643 if (usb_pipein(ep->pipe) ||
644 snd_usb_endpoint_implicit_feedback_sink(ep)) {
645
646 urb_packs = packs_per_ms;
647 /*
648 * Wireless devices can poll at a max rate of once per 4ms.
649 * For dataintervals less than 5, increase the packet count to
650 * allow the host controller to use bursting to fill in the
651 * gaps.
652 */
653 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_WIRELESS) {
654 int interval = ep->datainterval;
655 while (interval < 5) {
656 urb_packs <<= 1;
657 ++interval;
658 }
659 }
660 /* make capture URBs <= 1 ms and smaller than a period */
661 urb_packs = min(max_packs_per_urb, urb_packs);
662 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
663 urb_packs >>= 1;
664 ep->nurbs = MAX_URBS;
665
666 /*
667 * Playback endpoints without implicit sync are adjusted so that
668 * a period fits as evenly as possible in the smallest number of
669 * URBs. The total number of URBs is adjusted to the size of the
670 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
671 */
672 } else {
673 /* determine how small a packet can be */
674 minsize = (ep->freqn >> (16 - ep->datainterval)) *
675 (frame_bits >> 3);
676 /* with sync from device, assume it can be 12% lower */
677 if (sync_ep)
678 minsize -= minsize >> 3;
679 minsize = max(minsize, 1u);
680
681 /* how many packets will contain an entire ALSA period? */
682 max_packs_per_period = DIV_ROUND_UP(period_bytes, minsize);
683
684 /* how many URBs will contain a period? */
685 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
686 max_packs_per_urb);
687 /* how many packets are needed in each URB? */
688 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
689
690 /* limit the number of frames in a single URB */
691 ep->max_urb_frames = DIV_ROUND_UP(frames_per_period,
692 urbs_per_period);
693
694 /* try to use enough URBs to contain an entire ALSA buffer */
695 max_urbs = min((unsigned) MAX_URBS,
696 MAX_QUEUE * packs_per_ms / urb_packs);
697 ep->nurbs = min(max_urbs, urbs_per_period * periods_per_buffer);
698 }
699
700 /* allocate and initialize data urbs */
701 for (i = 0; i < ep->nurbs; i++) {
702 struct snd_urb_ctx *u = &ep->urb[i];
703 u->index = i;
704 u->ep = ep;
705 u->packets = urb_packs;
706 u->buffer_size = maxsize * u->packets;
707
708 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
709 u->packets++; /* for transfer delimiter */
710 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
711 if (!u->urb)
712 goto out_of_memory;
713
714 u->urb->transfer_buffer =
715 usb_alloc_coherent(ep->chip->dev, u->buffer_size,
716 GFP_KERNEL, &u->urb->transfer_dma);
717 if (!u->urb->transfer_buffer)
718 goto out_of_memory;
719 u->urb->pipe = ep->pipe;
720 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
721 u->urb->interval = 1 << ep->datainterval;
722 u->urb->context = u;
723 u->urb->complete = snd_complete_urb;
724 INIT_LIST_HEAD(&u->ready_list);
725 }
726
727 return 0;
728
729out_of_memory:
730 release_urbs(ep, 0);
731 return -ENOMEM;
732}
733
734/*
735 * configure a sync endpoint
736 */
737static int sync_ep_set_params(struct snd_usb_endpoint *ep)
738{
739 int i;
740
741 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4,
742 GFP_KERNEL, &ep->sync_dma);
743 if (!ep->syncbuf)
744 return -ENOMEM;
745
746 for (i = 0; i < SYNC_URBS; i++) {
747 struct snd_urb_ctx *u = &ep->urb[i];
748 u->index = i;
749 u->ep = ep;
750 u->packets = 1;
751 u->urb = usb_alloc_urb(1, GFP_KERNEL);
752 if (!u->urb)
753 goto out_of_memory;
754 u->urb->transfer_buffer = ep->syncbuf + i * 4;
755 u->urb->transfer_dma = ep->sync_dma + i * 4;
756 u->urb->transfer_buffer_length = 4;
757 u->urb->pipe = ep->pipe;
758 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
759 u->urb->number_of_packets = 1;
760 u->urb->interval = 1 << ep->syncinterval;
761 u->urb->context = u;
762 u->urb->complete = snd_complete_urb;
763 }
764
765 ep->nurbs = SYNC_URBS;
766
767 return 0;
768
769out_of_memory:
770 release_urbs(ep, 0);
771 return -ENOMEM;
772}
773
774/**
775 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
776 *
777 * @ep: the snd_usb_endpoint to configure
778 * @pcm_format: the audio fomat.
779 * @channels: the number of audio channels.
780 * @period_bytes: the number of bytes in one alsa period.
781 * @period_frames: the number of frames in one alsa period.
782 * @buffer_periods: the number of periods in one alsa buffer.
783 * @rate: the frame rate.
784 * @fmt: the USB audio format information
785 * @sync_ep: the sync endpoint to use, if any
786 *
787 * Determine the number of URBs to be used on this endpoint.
788 * An endpoint must be configured before it can be started.
789 * An endpoint that is already running can not be reconfigured.
790 */
791int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
792 snd_pcm_format_t pcm_format,
793 unsigned int channels,
794 unsigned int period_bytes,
795 unsigned int period_frames,
796 unsigned int buffer_periods,
797 unsigned int rate,
798 struct audioformat *fmt,
799 struct snd_usb_endpoint *sync_ep)
800{
801 int err;
802
803 if (ep->use_count != 0) {
804 usb_audio_warn(ep->chip,
805 "Unable to change format on ep #%x: already in use\n",
806 ep->ep_num);
807 return -EBUSY;
808 }
809
810 /* release old buffers, if any */
811 release_urbs(ep, 0);
812
813 ep->datainterval = fmt->datainterval;
814 ep->maxpacksize = fmt->maxpacksize;
815 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
816
817 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL)
818 ep->freqn = get_usb_full_speed_rate(rate);
819 else
820 ep->freqn = get_usb_high_speed_rate(rate);
821
822 /* calculate the frequency in 16.16 format */
823 ep->freqm = ep->freqn;
824 ep->freqshift = INT_MIN;
825
826 ep->phase = 0;
827
828 switch (ep->type) {
829 case SND_USB_ENDPOINT_TYPE_DATA:
830 err = data_ep_set_params(ep, pcm_format, channels,
831 period_bytes, period_frames,
832 buffer_periods, fmt, sync_ep);
833 break;
834 case SND_USB_ENDPOINT_TYPE_SYNC:
835 err = sync_ep_set_params(ep);
836 break;
837 default:
838 err = -EINVAL;
839 }
840
841 usb_audio_dbg(ep->chip,
842 "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
843 ep->ep_num, ep->type, ep->nurbs, err);
844
845 return err;
846}
847
848/**
849 * snd_usb_endpoint_start: start an snd_usb_endpoint
850 *
851 * @ep: the endpoint to start
852 * @can_sleep: flag indicating whether the operation is executed in
853 * non-atomic context
854 *
855 * A call to this function will increment the use count of the endpoint.
856 * In case it is not already running, the URBs for this endpoint will be
857 * submitted. Otherwise, this function does nothing.
858 *
859 * Must be balanced to calls of snd_usb_endpoint_stop().
860 *
861 * Returns an error if the URB submission failed, 0 in all other cases.
862 */
863int snd_usb_endpoint_start(struct snd_usb_endpoint *ep, bool can_sleep)
864{
865 int err;
866 unsigned int i;
867
868 if (ep->chip->shutdown)
869 return -EBADFD;
870
871 /* already running? */
872 if (++ep->use_count != 1)
873 return 0;
874
875 /* just to be sure */
876 deactivate_urbs(ep, false);
877 if (can_sleep)
878 wait_clear_urbs(ep);
879
880 ep->active_mask = 0;
881 ep->unlink_mask = 0;
882 ep->phase = 0;
883
884 snd_usb_endpoint_start_quirk(ep);
885
886 /*
887 * If this endpoint has a data endpoint as implicit feedback source,
888 * don't start the urbs here. Instead, mark them all as available,
889 * wait for the record urbs to return and queue the playback urbs
890 * from that context.
891 */
892
893 set_bit(EP_FLAG_RUNNING, &ep->flags);
894
895 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
896 for (i = 0; i < ep->nurbs; i++) {
897 struct snd_urb_ctx *ctx = ep->urb + i;
898 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
899 }
900
901 return 0;
902 }
903
904 for (i = 0; i < ep->nurbs; i++) {
905 struct urb *urb = ep->urb[i].urb;
906
907 if (snd_BUG_ON(!urb))
908 goto __error;
909
910 if (usb_pipeout(ep->pipe)) {
911 prepare_outbound_urb(ep, urb->context);
912 } else {
913 prepare_inbound_urb(ep, urb->context);
914 }
915
916 err = usb_submit_urb(urb, GFP_ATOMIC);
917 if (err < 0) {
918 usb_audio_err(ep->chip,
919 "cannot submit urb %d, error %d: %s\n",
920 i, err, usb_error_string(err));
921 goto __error;
922 }
923 set_bit(i, &ep->active_mask);
924 }
925
926 return 0;
927
928__error:
929 clear_bit(EP_FLAG_RUNNING, &ep->flags);
930 ep->use_count--;
931 deactivate_urbs(ep, false);
932 return -EPIPE;
933}
934
935/**
936 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
937 *
938 * @ep: the endpoint to stop (may be NULL)
939 *
940 * A call to this function will decrement the use count of the endpoint.
941 * In case the last user has requested the endpoint stop, the URBs will
942 * actually be deactivated.
943 *
944 * Must be balanced to calls of snd_usb_endpoint_start().
945 *
946 * The caller needs to synchronize the pending stop operation via
947 * snd_usb_endpoint_sync_pending_stop().
948 */
949void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep)
950{
951 if (!ep)
952 return;
953
954 if (snd_BUG_ON(ep->use_count == 0))
955 return;
956
957 if (--ep->use_count == 0) {
958 deactivate_urbs(ep, false);
959 ep->data_subs = NULL;
960 ep->sync_slave = NULL;
961 ep->retire_data_urb = NULL;
962 ep->prepare_data_urb = NULL;
963 set_bit(EP_FLAG_STOPPING, &ep->flags);
964 }
965}
966
967/**
968 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
969 *
970 * @ep: the endpoint to deactivate
971 *
972 * If the endpoint is not currently in use, this functions will
973 * deactivate its associated URBs.
974 *
975 * In case of any active users, this functions does nothing.
976 */
977void snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep)
978{
979 if (!ep)
980 return;
981
982 if (ep->use_count != 0)
983 return;
984
985 deactivate_urbs(ep, true);
986 wait_clear_urbs(ep);
987}
988
989/**
990 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
991 *
992 * @ep: the list header of the endpoint to free
993 *
994 * This function does not care for the endpoint's use count but will tear
995 * down all the streaming URBs immediately and free all resources.
996 */
997void snd_usb_endpoint_free(struct list_head *head)
998{
999 struct snd_usb_endpoint *ep;
1000
1001 ep = list_entry(head, struct snd_usb_endpoint, list);
1002 release_urbs(ep, 1);
1003 kfree(ep);
1004}
1005
1006/**
1007 * snd_usb_handle_sync_urb: parse an USB sync packet
1008 *
1009 * @ep: the endpoint to handle the packet
1010 * @sender: the sending endpoint
1011 * @urb: the received packet
1012 *
1013 * This function is called from the context of an endpoint that received
1014 * the packet and is used to let another endpoint object handle the payload.
1015 */
1016void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1017 struct snd_usb_endpoint *sender,
1018 const struct urb *urb)
1019{
1020 int shift;
1021 unsigned int f;
1022 unsigned long flags;
1023
1024 snd_BUG_ON(ep == sender);
1025
1026 /*
1027 * In case the endpoint is operating in implicit feedback mode, prepare
1028 * a new outbound URB that has the same layout as the received packet
1029 * and add it to the list of pending urbs. queue_pending_output_urbs()
1030 * will take care of them later.
1031 */
1032 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1033 ep->use_count != 0) {
1034
1035 /* implicit feedback case */
1036 int i, bytes = 0;
1037 struct snd_urb_ctx *in_ctx;
1038 struct snd_usb_packet_info *out_packet;
1039
1040 in_ctx = urb->context;
1041
1042 /* Count overall packet size */
1043 for (i = 0; i < in_ctx->packets; i++)
1044 if (urb->iso_frame_desc[i].status == 0)
1045 bytes += urb->iso_frame_desc[i].actual_length;
1046
1047 /*
1048 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1049 * streaming once it received a 0-byte OUT URB
1050 */
1051 if (bytes == 0)
1052 return;
1053
1054 spin_lock_irqsave(&ep->lock, flags);
1055 out_packet = ep->next_packet + ep->next_packet_write_pos;
1056
1057 /*
1058 * Iterate through the inbound packet and prepare the lengths
1059 * for the output packet. The OUT packet we are about to send
1060 * will have the same amount of payload bytes per stride as the
1061 * IN packet we just received. Since the actual size is scaled
1062 * by the stride, use the sender stride to calculate the length
1063 * in case the number of channels differ between the implicitly
1064 * fed-back endpoint and the synchronizing endpoint.
1065 */
1066
1067 out_packet->packets = in_ctx->packets;
1068 for (i = 0; i < in_ctx->packets; i++) {
1069 if (urb->iso_frame_desc[i].status == 0)
1070 out_packet->packet_size[i] =
1071 urb->iso_frame_desc[i].actual_length / sender->stride;
1072 else
1073 out_packet->packet_size[i] = 0;
1074 }
1075
1076 ep->next_packet_write_pos++;
1077 ep->next_packet_write_pos %= MAX_URBS;
1078 spin_unlock_irqrestore(&ep->lock, flags);
1079 queue_pending_output_urbs(ep);
1080
1081 return;
1082 }
1083
1084 /*
1085 * process after playback sync complete
1086 *
1087 * Full speed devices report feedback values in 10.14 format as samples
1088 * per frame, high speed devices in 16.16 format as samples per
1089 * microframe.
1090 *
1091 * Because the Audio Class 1 spec was written before USB 2.0, many high
1092 * speed devices use a wrong interpretation, some others use an
1093 * entirely different format.
1094 *
1095 * Therefore, we cannot predict what format any particular device uses
1096 * and must detect it automatically.
1097 */
1098
1099 if (urb->iso_frame_desc[0].status != 0 ||
1100 urb->iso_frame_desc[0].actual_length < 3)
1101 return;
1102
1103 f = le32_to_cpup(urb->transfer_buffer);
1104 if (urb->iso_frame_desc[0].actual_length == 3)
1105 f &= 0x00ffffff;
1106 else
1107 f &= 0x0fffffff;
1108
1109 if (f == 0)
1110 return;
1111
1112 if (unlikely(sender->udh01_fb_quirk)) {
1113 /*
1114 * The TEAC UD-H01 firmware sometimes changes the feedback value
1115 * by +/- 0x1.0000.
1116 */
1117 if (f < ep->freqn - 0x8000)
1118 f += 0x10000;
1119 else if (f > ep->freqn + 0x8000)
1120 f -= 0x10000;
1121 } else if (unlikely(ep->freqshift == INT_MIN)) {
1122 /*
1123 * The first time we see a feedback value, determine its format
1124 * by shifting it left or right until it matches the nominal
1125 * frequency value. This assumes that the feedback does not
1126 * differ from the nominal value more than +50% or -25%.
1127 */
1128 shift = 0;
1129 while (f < ep->freqn - ep->freqn / 4) {
1130 f <<= 1;
1131 shift++;
1132 }
1133 while (f > ep->freqn + ep->freqn / 2) {
1134 f >>= 1;
1135 shift--;
1136 }
1137 ep->freqshift = shift;
1138 } else if (ep->freqshift >= 0)
1139 f <<= ep->freqshift;
1140 else
1141 f >>= -ep->freqshift;
1142
1143 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1144 /*
1145 * If the frequency looks valid, set it.
1146 * This value is referred to in prepare_playback_urb().
1147 */
1148 spin_lock_irqsave(&ep->lock, flags);
1149 ep->freqm = f;
1150 spin_unlock_irqrestore(&ep->lock, flags);
1151 } else {
1152 /*
1153 * Out of range; maybe the shift value is wrong.
1154 * Reset it so that we autodetect again the next time.
1155 */
1156 ep->freqshift = INT_MIN;
1157 }
1158}
1159