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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 */
4
5#include <linux/gfp.h>
6#include <linux/init.h>
7#include <linux/ratelimit.h>
8#include <linux/usb.h>
9#include <linux/usb/audio.h>
10#include <linux/slab.h>
11
12#include <sound/core.h>
13#include <sound/pcm.h>
14#include <sound/pcm_params.h>
15
16#include "usbaudio.h"
17#include "helper.h"
18#include "card.h"
19#include "endpoint.h"
20#include "pcm.h"
21#include "quirks.h"
22
23#define EP_FLAG_RUNNING 1
24#define EP_FLAG_STOPPING 2
25
26/*
27 * snd_usb_endpoint is a model that abstracts everything related to an
28 * USB endpoint and its streaming.
29 *
30 * There are functions to activate and deactivate the streaming URBs and
31 * optional callbacks to let the pcm logic handle the actual content of the
32 * packets for playback and record. Thus, the bus streaming and the audio
33 * handlers are fully decoupled.
34 *
35 * There are two different types of endpoints in audio applications.
36 *
37 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
38 * inbound and outbound traffic.
39 *
40 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
41 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
42 * (3 or 4 bytes).
43 *
44 * Each endpoint has to be configured prior to being used by calling
45 * snd_usb_endpoint_set_params().
46 *
47 * The model incorporates a reference counting, so that multiple users
48 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
49 * only the first user will effectively start the URBs, and only the last
50 * one to stop it will tear the URBs down again.
51 */
52
53/*
54 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
55 * this will overflow at approx 524 kHz
56 */
57static inline unsigned get_usb_full_speed_rate(unsigned int rate)
58{
59 return ((rate << 13) + 62) / 125;
60}
61
62/*
63 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
64 * this will overflow at approx 4 MHz
65 */
66static inline unsigned get_usb_high_speed_rate(unsigned int rate)
67{
68 return ((rate << 10) + 62) / 125;
69}
70
71/*
72 * release a urb data
73 */
74static void release_urb_ctx(struct snd_urb_ctx *u)
75{
76 if (u->buffer_size)
77 usb_free_coherent(u->ep->chip->dev, u->buffer_size,
78 u->urb->transfer_buffer,
79 u->urb->transfer_dma);
80 usb_free_urb(u->urb);
81 u->urb = NULL;
82}
83
84static const char *usb_error_string(int err)
85{
86 switch (err) {
87 case -ENODEV:
88 return "no device";
89 case -ENOENT:
90 return "endpoint not enabled";
91 case -EPIPE:
92 return "endpoint stalled";
93 case -ENOSPC:
94 return "not enough bandwidth";
95 case -ESHUTDOWN:
96 return "device disabled";
97 case -EHOSTUNREACH:
98 return "device suspended";
99 case -EINVAL:
100 case -EAGAIN:
101 case -EFBIG:
102 case -EMSGSIZE:
103 return "internal error";
104 default:
105 return "unknown error";
106 }
107}
108
109/**
110 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
111 *
112 * @ep: The snd_usb_endpoint
113 *
114 * Determine whether an endpoint is driven by an implicit feedback
115 * data endpoint source.
116 */
117int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
118{
119 return ep->sync_master &&
120 ep->sync_master->type == SND_USB_ENDPOINT_TYPE_DATA &&
121 ep->type == SND_USB_ENDPOINT_TYPE_DATA &&
122 usb_pipeout(ep->pipe);
123}
124
125/*
126 * For streaming based on information derived from sync endpoints,
127 * prepare_outbound_urb_sizes() will call slave_next_packet_size() to
128 * determine the number of samples to be sent in the next packet.
129 *
130 * For implicit feedback, slave_next_packet_size() is unused.
131 */
132int snd_usb_endpoint_slave_next_packet_size(struct snd_usb_endpoint *ep)
133{
134 unsigned long flags;
135 int ret;
136
137 if (ep->fill_max)
138 return ep->maxframesize;
139
140 spin_lock_irqsave(&ep->lock, flags);
141 ep->phase = (ep->phase & 0xffff)
142 + (ep->freqm << ep->datainterval);
143 ret = min(ep->phase >> 16, ep->maxframesize);
144 spin_unlock_irqrestore(&ep->lock, flags);
145
146 return ret;
147}
148
149/*
150 * For adaptive and synchronous endpoints, prepare_outbound_urb_sizes()
151 * will call next_packet_size() to determine the number of samples to be
152 * sent in the next packet.
153 */
154int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep)
155{
156 int ret;
157
158 if (ep->fill_max)
159 return ep->maxframesize;
160
161 ep->sample_accum += ep->sample_rem;
162 if (ep->sample_accum >= ep->pps) {
163 ep->sample_accum -= ep->pps;
164 ret = ep->packsize[1];
165 } else {
166 ret = ep->packsize[0];
167 }
168
169 return ret;
170}
171
172static void retire_outbound_urb(struct snd_usb_endpoint *ep,
173 struct snd_urb_ctx *urb_ctx)
174{
175 if (ep->retire_data_urb)
176 ep->retire_data_urb(ep->data_subs, urb_ctx->urb);
177}
178
179static void retire_inbound_urb(struct snd_usb_endpoint *ep,
180 struct snd_urb_ctx *urb_ctx)
181{
182 struct urb *urb = urb_ctx->urb;
183
184 if (unlikely(ep->skip_packets > 0)) {
185 ep->skip_packets--;
186 return;
187 }
188
189 if (ep->sync_slave)
190 snd_usb_handle_sync_urb(ep->sync_slave, ep, urb);
191
192 if (ep->retire_data_urb)
193 ep->retire_data_urb(ep->data_subs, urb);
194}
195
196static void prepare_silent_urb(struct snd_usb_endpoint *ep,
197 struct snd_urb_ctx *ctx)
198{
199 struct urb *urb = ctx->urb;
200 unsigned int offs = 0;
201 unsigned int extra = 0;
202 __le32 packet_length;
203 int i;
204
205 /* For tx_length_quirk, put packet length at start of packet */
206 if (ep->chip->tx_length_quirk)
207 extra = sizeof(packet_length);
208
209 for (i = 0; i < ctx->packets; ++i) {
210 unsigned int offset;
211 unsigned int length;
212 int counts;
213
214 if (ctx->packet_size[i])
215 counts = ctx->packet_size[i];
216 else if (ep->sync_master)
217 counts = snd_usb_endpoint_slave_next_packet_size(ep);
218 else
219 counts = snd_usb_endpoint_next_packet_size(ep);
220
221 length = counts * ep->stride; /* number of silent bytes */
222 offset = offs * ep->stride + extra * i;
223 urb->iso_frame_desc[i].offset = offset;
224 urb->iso_frame_desc[i].length = length + extra;
225 if (extra) {
226 packet_length = cpu_to_le32(length);
227 memcpy(urb->transfer_buffer + offset,
228 &packet_length, sizeof(packet_length));
229 }
230 memset(urb->transfer_buffer + offset + extra,
231 ep->silence_value, length);
232 offs += counts;
233 }
234
235 urb->number_of_packets = ctx->packets;
236 urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
237}
238
239/*
240 * Prepare a PLAYBACK urb for submission to the bus.
241 */
242static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
243 struct snd_urb_ctx *ctx)
244{
245 struct urb *urb = ctx->urb;
246 unsigned char *cp = urb->transfer_buffer;
247
248 urb->dev = ep->chip->dev; /* we need to set this at each time */
249
250 switch (ep->type) {
251 case SND_USB_ENDPOINT_TYPE_DATA:
252 if (ep->prepare_data_urb) {
253 ep->prepare_data_urb(ep->data_subs, urb);
254 } else {
255 /* no data provider, so send silence */
256 prepare_silent_urb(ep, ctx);
257 }
258 break;
259
260 case SND_USB_ENDPOINT_TYPE_SYNC:
261 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
262 /*
263 * fill the length and offset of each urb descriptor.
264 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
265 */
266 urb->iso_frame_desc[0].length = 4;
267 urb->iso_frame_desc[0].offset = 0;
268 cp[0] = ep->freqn;
269 cp[1] = ep->freqn >> 8;
270 cp[2] = ep->freqn >> 16;
271 cp[3] = ep->freqn >> 24;
272 } else {
273 /*
274 * fill the length and offset of each urb descriptor.
275 * the fixed 10.14 frequency is passed through the pipe.
276 */
277 urb->iso_frame_desc[0].length = 3;
278 urb->iso_frame_desc[0].offset = 0;
279 cp[0] = ep->freqn >> 2;
280 cp[1] = ep->freqn >> 10;
281 cp[2] = ep->freqn >> 18;
282 }
283
284 break;
285 }
286}
287
288/*
289 * Prepare a CAPTURE or SYNC urb for submission to the bus.
290 */
291static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep,
292 struct snd_urb_ctx *urb_ctx)
293{
294 int i, offs;
295 struct urb *urb = urb_ctx->urb;
296
297 urb->dev = ep->chip->dev; /* we need to set this at each time */
298
299 switch (ep->type) {
300 case SND_USB_ENDPOINT_TYPE_DATA:
301 offs = 0;
302 for (i = 0; i < urb_ctx->packets; i++) {
303 urb->iso_frame_desc[i].offset = offs;
304 urb->iso_frame_desc[i].length = ep->curpacksize;
305 offs += ep->curpacksize;
306 }
307
308 urb->transfer_buffer_length = offs;
309 urb->number_of_packets = urb_ctx->packets;
310 break;
311
312 case SND_USB_ENDPOINT_TYPE_SYNC:
313 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
314 urb->iso_frame_desc[0].offset = 0;
315 break;
316 }
317}
318
319/*
320 * Send output urbs that have been prepared previously. URBs are dequeued
321 * from ep->ready_playback_urbs and in case there there aren't any available
322 * or there are no packets that have been prepared, this function does
323 * nothing.
324 *
325 * The reason why the functionality of sending and preparing URBs is separated
326 * is that host controllers don't guarantee the order in which they return
327 * inbound and outbound packets to their submitters.
328 *
329 * This function is only used for implicit feedback endpoints. For endpoints
330 * driven by dedicated sync endpoints, URBs are immediately re-submitted
331 * from their completion handler.
332 */
333static void queue_pending_output_urbs(struct snd_usb_endpoint *ep)
334{
335 while (test_bit(EP_FLAG_RUNNING, &ep->flags)) {
336
337 unsigned long flags;
338 struct snd_usb_packet_info *packet;
339 struct snd_urb_ctx *ctx = NULL;
340 int err, i;
341
342 spin_lock_irqsave(&ep->lock, flags);
343 if (ep->next_packet_read_pos != ep->next_packet_write_pos) {
344 packet = ep->next_packet + ep->next_packet_read_pos;
345 ep->next_packet_read_pos++;
346 ep->next_packet_read_pos %= MAX_URBS;
347
348 /* take URB out of FIFO */
349 if (!list_empty(&ep->ready_playback_urbs)) {
350 ctx = list_first_entry(&ep->ready_playback_urbs,
351 struct snd_urb_ctx, ready_list);
352 list_del_init(&ctx->ready_list);
353 }
354 }
355 spin_unlock_irqrestore(&ep->lock, flags);
356
357 if (ctx == NULL)
358 return;
359
360 /* copy over the length information */
361 for (i = 0; i < packet->packets; i++)
362 ctx->packet_size[i] = packet->packet_size[i];
363
364 /* call the data handler to fill in playback data */
365 prepare_outbound_urb(ep, ctx);
366
367 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
368 if (err < 0)
369 usb_audio_err(ep->chip,
370 "Unable to submit urb #%d: %d (urb %p)\n",
371 ctx->index, err, ctx->urb);
372 else
373 set_bit(ctx->index, &ep->active_mask);
374 }
375}
376
377/*
378 * complete callback for urbs
379 */
380static void snd_complete_urb(struct urb *urb)
381{
382 struct snd_urb_ctx *ctx = urb->context;
383 struct snd_usb_endpoint *ep = ctx->ep;
384 struct snd_pcm_substream *substream;
385 unsigned long flags;
386 int err;
387
388 if (unlikely(urb->status == -ENOENT || /* unlinked */
389 urb->status == -ENODEV || /* device removed */
390 urb->status == -ECONNRESET || /* unlinked */
391 urb->status == -ESHUTDOWN)) /* device disabled */
392 goto exit_clear;
393 /* device disconnected */
394 if (unlikely(atomic_read(&ep->chip->shutdown)))
395 goto exit_clear;
396
397 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
398 goto exit_clear;
399
400 if (usb_pipeout(ep->pipe)) {
401 retire_outbound_urb(ep, ctx);
402 /* can be stopped during retire callback */
403 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
404 goto exit_clear;
405
406 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
407 spin_lock_irqsave(&ep->lock, flags);
408 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
409 spin_unlock_irqrestore(&ep->lock, flags);
410 queue_pending_output_urbs(ep);
411
412 goto exit_clear;
413 }
414
415 prepare_outbound_urb(ep, ctx);
416 /* can be stopped during prepare callback */
417 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
418 goto exit_clear;
419 } else {
420 retire_inbound_urb(ep, ctx);
421 /* can be stopped during retire callback */
422 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
423 goto exit_clear;
424
425 prepare_inbound_urb(ep, ctx);
426 }
427
428 err = usb_submit_urb(urb, GFP_ATOMIC);
429 if (err == 0)
430 return;
431
432 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
433 if (ep->data_subs && ep->data_subs->pcm_substream) {
434 substream = ep->data_subs->pcm_substream;
435 snd_pcm_stop_xrun(substream);
436 }
437
438exit_clear:
439 clear_bit(ctx->index, &ep->active_mask);
440}
441
442/**
443 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
444 *
445 * @chip: The chip
446 * @alts: The USB host interface
447 * @ep_num: The number of the endpoint to use
448 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
449 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
450 *
451 * If the requested endpoint has not been added to the given chip before,
452 * a new instance is created. Otherwise, a pointer to the previoulsy
453 * created instance is returned. In case of any error, NULL is returned.
454 *
455 * New endpoints will be added to chip->ep_list and must be freed by
456 * calling snd_usb_endpoint_free().
457 *
458 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
459 * bNumEndpoints > 1 beforehand.
460 */
461struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
462 struct usb_host_interface *alts,
463 int ep_num, int direction, int type)
464{
465 struct snd_usb_endpoint *ep;
466 int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK;
467
468 if (WARN_ON(!alts))
469 return NULL;
470
471 mutex_lock(&chip->mutex);
472
473 list_for_each_entry(ep, &chip->ep_list, list) {
474 if (ep->ep_num == ep_num &&
475 ep->iface == alts->desc.bInterfaceNumber &&
476 ep->altsetting == alts->desc.bAlternateSetting) {
477 usb_audio_dbg(ep->chip,
478 "Re-using EP %x in iface %d,%d @%p\n",
479 ep_num, ep->iface, ep->altsetting, ep);
480 goto __exit_unlock;
481 }
482 }
483
484 usb_audio_dbg(chip, "Creating new %s %s endpoint #%x\n",
485 is_playback ? "playback" : "capture",
486 type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync",
487 ep_num);
488
489 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
490 if (!ep)
491 goto __exit_unlock;
492
493 ep->chip = chip;
494 spin_lock_init(&ep->lock);
495 ep->type = type;
496 ep->ep_num = ep_num;
497 ep->iface = alts->desc.bInterfaceNumber;
498 ep->altsetting = alts->desc.bAlternateSetting;
499 INIT_LIST_HEAD(&ep->ready_playback_urbs);
500 ep_num &= USB_ENDPOINT_NUMBER_MASK;
501
502 if (is_playback)
503 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
504 else
505 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
506
507 if (type == SND_USB_ENDPOINT_TYPE_SYNC) {
508 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
509 get_endpoint(alts, 1)->bRefresh >= 1 &&
510 get_endpoint(alts, 1)->bRefresh <= 9)
511 ep->syncinterval = get_endpoint(alts, 1)->bRefresh;
512 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
513 ep->syncinterval = 1;
514 else if (get_endpoint(alts, 1)->bInterval >= 1 &&
515 get_endpoint(alts, 1)->bInterval <= 16)
516 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1;
517 else
518 ep->syncinterval = 3;
519
520 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize);
521 }
522
523 list_add_tail(&ep->list, &chip->ep_list);
524
525 ep->is_implicit_feedback = 0;
526
527__exit_unlock:
528 mutex_unlock(&chip->mutex);
529
530 return ep;
531}
532
533/*
534 * wait until all urbs are processed.
535 */
536static int wait_clear_urbs(struct snd_usb_endpoint *ep)
537{
538 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
539 int alive;
540
541 do {
542 alive = bitmap_weight(&ep->active_mask, ep->nurbs);
543 if (!alive)
544 break;
545
546 schedule_timeout_uninterruptible(1);
547 } while (time_before(jiffies, end_time));
548
549 if (alive)
550 usb_audio_err(ep->chip,
551 "timeout: still %d active urbs on EP #%x\n",
552 alive, ep->ep_num);
553 clear_bit(EP_FLAG_STOPPING, &ep->flags);
554
555 ep->data_subs = NULL;
556 ep->sync_slave = NULL;
557 ep->retire_data_urb = NULL;
558 ep->prepare_data_urb = NULL;
559
560 return 0;
561}
562
563/* sync the pending stop operation;
564 * this function itself doesn't trigger the stop operation
565 */
566void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
567{
568 if (ep && test_bit(EP_FLAG_STOPPING, &ep->flags))
569 wait_clear_urbs(ep);
570}
571
572/*
573 * unlink active urbs.
574 */
575static int deactivate_urbs(struct snd_usb_endpoint *ep, bool force)
576{
577 unsigned int i;
578
579 if (!force && atomic_read(&ep->chip->shutdown)) /* to be sure... */
580 return -EBADFD;
581
582 clear_bit(EP_FLAG_RUNNING, &ep->flags);
583
584 INIT_LIST_HEAD(&ep->ready_playback_urbs);
585 ep->next_packet_read_pos = 0;
586 ep->next_packet_write_pos = 0;
587
588 for (i = 0; i < ep->nurbs; i++) {
589 if (test_bit(i, &ep->active_mask)) {
590 if (!test_and_set_bit(i, &ep->unlink_mask)) {
591 struct urb *u = ep->urb[i].urb;
592 usb_unlink_urb(u);
593 }
594 }
595 }
596
597 return 0;
598}
599
600/*
601 * release an endpoint's urbs
602 */
603static void release_urbs(struct snd_usb_endpoint *ep, int force)
604{
605 int i;
606
607 /* route incoming urbs to nirvana */
608 ep->retire_data_urb = NULL;
609 ep->prepare_data_urb = NULL;
610
611 /* stop urbs */
612 deactivate_urbs(ep, force);
613 wait_clear_urbs(ep);
614
615 for (i = 0; i < ep->nurbs; i++)
616 release_urb_ctx(&ep->urb[i]);
617
618 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
619 ep->syncbuf, ep->sync_dma);
620
621 ep->syncbuf = NULL;
622 ep->nurbs = 0;
623}
624
625/*
626 * Check data endpoint for format differences
627 */
628static bool check_ep_params(struct snd_usb_endpoint *ep,
629 snd_pcm_format_t pcm_format,
630 unsigned int channels,
631 unsigned int period_bytes,
632 unsigned int frames_per_period,
633 unsigned int periods_per_buffer,
634 struct audioformat *fmt,
635 struct snd_usb_endpoint *sync_ep)
636{
637 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
638 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
639 unsigned int max_urbs;
640 int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels;
641 int tx_length_quirk = (ep->chip->tx_length_quirk &&
642 usb_pipeout(ep->pipe));
643 bool ret = 1;
644
645 if (pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
646 /*
647 * When operating in DSD DOP mode, the size of a sample frame
648 * in hardware differs from the actual physical format width
649 * because we need to make room for the DOP markers.
650 */
651 frame_bits += channels << 3;
652 }
653
654 ret = ret && (ep->datainterval == fmt->datainterval);
655 ret = ret && (ep->stride == frame_bits >> 3);
656
657 switch (pcm_format) {
658 case SNDRV_PCM_FORMAT_U8:
659 ret = ret && (ep->silence_value == 0x80);
660 break;
661 case SNDRV_PCM_FORMAT_DSD_U8:
662 case SNDRV_PCM_FORMAT_DSD_U16_LE:
663 case SNDRV_PCM_FORMAT_DSD_U32_LE:
664 case SNDRV_PCM_FORMAT_DSD_U16_BE:
665 case SNDRV_PCM_FORMAT_DSD_U32_BE:
666 ret = ret && (ep->silence_value == 0x69);
667 break;
668 default:
669 ret = ret && (ep->silence_value == 0);
670 }
671
672 /* assume max. frequency is 50% higher than nominal */
673 ret = ret && (ep->freqmax == ep->freqn + (ep->freqn >> 1));
674 /* Round up freqmax to nearest integer in order to calculate maximum
675 * packet size, which must represent a whole number of frames.
676 * This is accomplished by adding 0x0.ffff before converting the
677 * Q16.16 format into integer.
678 * In order to accurately calculate the maximum packet size when
679 * the data interval is more than 1 (i.e. ep->datainterval > 0),
680 * multiply by the data interval prior to rounding. For instance,
681 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
682 * frames with a data interval of 1, but 11 (10.25) frames with a
683 * data interval of 2.
684 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
685 * maximum datainterval value of 3, at USB full speed, higher for
686 * USB high speed, noting that ep->freqmax is in units of
687 * frames per packet in Q16.16 format.)
688 */
689 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
690 (frame_bits >> 3);
691 if (tx_length_quirk)
692 maxsize += sizeof(__le32); /* Space for length descriptor */
693 /* but wMaxPacketSize might reduce this */
694 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
695 /* whatever fits into a max. size packet */
696 unsigned int data_maxsize = maxsize = ep->maxpacksize;
697
698 if (tx_length_quirk)
699 /* Need to remove the length descriptor to calc freq */
700 data_maxsize -= sizeof(__le32);
701 ret = ret && (ep->freqmax == (data_maxsize / (frame_bits >> 3))
702 << (16 - ep->datainterval));
703 }
704
705 if (ep->fill_max)
706 ret = ret && (ep->curpacksize == ep->maxpacksize);
707 else
708 ret = ret && (ep->curpacksize == maxsize);
709
710 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) {
711 packs_per_ms = 8 >> ep->datainterval;
712 max_packs_per_urb = MAX_PACKS_HS;
713 } else {
714 packs_per_ms = 1;
715 max_packs_per_urb = MAX_PACKS;
716 }
717 if (sync_ep && !snd_usb_endpoint_implicit_feedback_sink(ep))
718 max_packs_per_urb = min(max_packs_per_urb,
719 1U << sync_ep->syncinterval);
720 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
721
722 /*
723 * Capture endpoints need to use small URBs because there's no way
724 * to tell in advance where the next period will end, and we don't
725 * want the next URB to complete much after the period ends.
726 *
727 * Playback endpoints with implicit sync much use the same parameters
728 * as their corresponding capture endpoint.
729 */
730 if (usb_pipein(ep->pipe) ||
731 snd_usb_endpoint_implicit_feedback_sink(ep)) {
732
733 urb_packs = packs_per_ms;
734 /*
735 * Wireless devices can poll at a max rate of once per 4ms.
736 * For dataintervals less than 5, increase the packet count to
737 * allow the host controller to use bursting to fill in the
738 * gaps.
739 */
740 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_WIRELESS) {
741 int interval = ep->datainterval;
742
743 while (interval < 5) {
744 urb_packs <<= 1;
745 ++interval;
746 }
747 }
748 /* make capture URBs <= 1 ms and smaller than a period */
749 urb_packs = min(max_packs_per_urb, urb_packs);
750 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
751 urb_packs >>= 1;
752 ret = ret && (ep->nurbs == MAX_URBS);
753
754 /*
755 * Playback endpoints without implicit sync are adjusted so that
756 * a period fits as evenly as possible in the smallest number of
757 * URBs. The total number of URBs is adjusted to the size of the
758 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
759 */
760 } else {
761 /* determine how small a packet can be */
762 minsize = (ep->freqn >> (16 - ep->datainterval)) *
763 (frame_bits >> 3);
764 /* with sync from device, assume it can be 12% lower */
765 if (sync_ep)
766 minsize -= minsize >> 3;
767 minsize = max(minsize, 1u);
768
769 /* how many packets will contain an entire ALSA period? */
770 max_packs_per_period = DIV_ROUND_UP(period_bytes, minsize);
771
772 /* how many URBs will contain a period? */
773 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
774 max_packs_per_urb);
775 /* how many packets are needed in each URB? */
776 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
777
778 /* limit the number of frames in a single URB */
779 ret = ret && (ep->max_urb_frames ==
780 DIV_ROUND_UP(frames_per_period, urbs_per_period));
781
782 /* try to use enough URBs to contain an entire ALSA buffer */
783 max_urbs = min((unsigned) MAX_URBS,
784 MAX_QUEUE * packs_per_ms / urb_packs);
785 ret = ret && (ep->nurbs == min(max_urbs,
786 urbs_per_period * periods_per_buffer));
787 }
788
789 ret = ret && (ep->datainterval == fmt->datainterval);
790 ret = ret && (ep->maxpacksize == fmt->maxpacksize);
791 ret = ret &&
792 (ep->fill_max == !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX));
793
794 return ret;
795}
796
797/*
798 * configure a data endpoint
799 */
800static int data_ep_set_params(struct snd_usb_endpoint *ep,
801 snd_pcm_format_t pcm_format,
802 unsigned int channels,
803 unsigned int period_bytes,
804 unsigned int frames_per_period,
805 unsigned int periods_per_buffer,
806 struct audioformat *fmt,
807 struct snd_usb_endpoint *sync_ep)
808{
809 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
810 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
811 unsigned int max_urbs, i;
812 int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels;
813 int tx_length_quirk = (ep->chip->tx_length_quirk &&
814 usb_pipeout(ep->pipe));
815
816 if (pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
817 /*
818 * When operating in DSD DOP mode, the size of a sample frame
819 * in hardware differs from the actual physical format width
820 * because we need to make room for the DOP markers.
821 */
822 frame_bits += channels << 3;
823 }
824
825 ep->datainterval = fmt->datainterval;
826 ep->stride = frame_bits >> 3;
827
828 switch (pcm_format) {
829 case SNDRV_PCM_FORMAT_U8:
830 ep->silence_value = 0x80;
831 break;
832 case SNDRV_PCM_FORMAT_DSD_U8:
833 case SNDRV_PCM_FORMAT_DSD_U16_LE:
834 case SNDRV_PCM_FORMAT_DSD_U32_LE:
835 case SNDRV_PCM_FORMAT_DSD_U16_BE:
836 case SNDRV_PCM_FORMAT_DSD_U32_BE:
837 ep->silence_value = 0x69;
838 break;
839 default:
840 ep->silence_value = 0;
841 }
842
843 /* assume max. frequency is 50% higher than nominal */
844 ep->freqmax = ep->freqn + (ep->freqn >> 1);
845 /* Round up freqmax to nearest integer in order to calculate maximum
846 * packet size, which must represent a whole number of frames.
847 * This is accomplished by adding 0x0.ffff before converting the
848 * Q16.16 format into integer.
849 * In order to accurately calculate the maximum packet size when
850 * the data interval is more than 1 (i.e. ep->datainterval > 0),
851 * multiply by the data interval prior to rounding. For instance,
852 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
853 * frames with a data interval of 1, but 11 (10.25) frames with a
854 * data interval of 2.
855 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
856 * maximum datainterval value of 3, at USB full speed, higher for
857 * USB high speed, noting that ep->freqmax is in units of
858 * frames per packet in Q16.16 format.)
859 */
860 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
861 (frame_bits >> 3);
862 if (tx_length_quirk)
863 maxsize += sizeof(__le32); /* Space for length descriptor */
864 /* but wMaxPacketSize might reduce this */
865 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
866 /* whatever fits into a max. size packet */
867 unsigned int data_maxsize = maxsize = ep->maxpacksize;
868
869 if (tx_length_quirk)
870 /* Need to remove the length descriptor to calc freq */
871 data_maxsize -= sizeof(__le32);
872 ep->freqmax = (data_maxsize / (frame_bits >> 3))
873 << (16 - ep->datainterval);
874 }
875
876 if (ep->fill_max)
877 ep->curpacksize = ep->maxpacksize;
878 else
879 ep->curpacksize = maxsize;
880
881 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) {
882 packs_per_ms = 8 >> ep->datainterval;
883 max_packs_per_urb = MAX_PACKS_HS;
884 } else {
885 packs_per_ms = 1;
886 max_packs_per_urb = MAX_PACKS;
887 }
888 if (sync_ep && !snd_usb_endpoint_implicit_feedback_sink(ep))
889 max_packs_per_urb = min(max_packs_per_urb,
890 1U << sync_ep->syncinterval);
891 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
892
893 /*
894 * Capture endpoints need to use small URBs because there's no way
895 * to tell in advance where the next period will end, and we don't
896 * want the next URB to complete much after the period ends.
897 *
898 * Playback endpoints with implicit sync much use the same parameters
899 * as their corresponding capture endpoint.
900 */
901 if (usb_pipein(ep->pipe) ||
902 snd_usb_endpoint_implicit_feedback_sink(ep)) {
903
904 urb_packs = packs_per_ms;
905 /*
906 * Wireless devices can poll at a max rate of once per 4ms.
907 * For dataintervals less than 5, increase the packet count to
908 * allow the host controller to use bursting to fill in the
909 * gaps.
910 */
911 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_WIRELESS) {
912 int interval = ep->datainterval;
913 while (interval < 5) {
914 urb_packs <<= 1;
915 ++interval;
916 }
917 }
918 /* make capture URBs <= 1 ms and smaller than a period */
919 urb_packs = min(max_packs_per_urb, urb_packs);
920 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
921 urb_packs >>= 1;
922 ep->nurbs = MAX_URBS;
923
924 /*
925 * Playback endpoints without implicit sync are adjusted so that
926 * a period fits as evenly as possible in the smallest number of
927 * URBs. The total number of URBs is adjusted to the size of the
928 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
929 */
930 } else {
931 /* determine how small a packet can be */
932 minsize = (ep->freqn >> (16 - ep->datainterval)) *
933 (frame_bits >> 3);
934 /* with sync from device, assume it can be 12% lower */
935 if (sync_ep)
936 minsize -= minsize >> 3;
937 minsize = max(minsize, 1u);
938
939 /* how many packets will contain an entire ALSA period? */
940 max_packs_per_period = DIV_ROUND_UP(period_bytes, minsize);
941
942 /* how many URBs will contain a period? */
943 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
944 max_packs_per_urb);
945 /* how many packets are needed in each URB? */
946 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
947
948 /* limit the number of frames in a single URB */
949 ep->max_urb_frames = DIV_ROUND_UP(frames_per_period,
950 urbs_per_period);
951
952 /* try to use enough URBs to contain an entire ALSA buffer */
953 max_urbs = min((unsigned) MAX_URBS,
954 MAX_QUEUE * packs_per_ms / urb_packs);
955 ep->nurbs = min(max_urbs, urbs_per_period * periods_per_buffer);
956 }
957
958 /* allocate and initialize data urbs */
959 for (i = 0; i < ep->nurbs; i++) {
960 struct snd_urb_ctx *u = &ep->urb[i];
961 u->index = i;
962 u->ep = ep;
963 u->packets = urb_packs;
964 u->buffer_size = maxsize * u->packets;
965
966 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
967 u->packets++; /* for transfer delimiter */
968 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
969 if (!u->urb)
970 goto out_of_memory;
971
972 u->urb->transfer_buffer =
973 usb_alloc_coherent(ep->chip->dev, u->buffer_size,
974 GFP_KERNEL, &u->urb->transfer_dma);
975 if (!u->urb->transfer_buffer)
976 goto out_of_memory;
977 u->urb->pipe = ep->pipe;
978 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
979 u->urb->interval = 1 << ep->datainterval;
980 u->urb->context = u;
981 u->urb->complete = snd_complete_urb;
982 INIT_LIST_HEAD(&u->ready_list);
983 }
984
985 return 0;
986
987out_of_memory:
988 release_urbs(ep, 0);
989 return -ENOMEM;
990}
991
992/*
993 * configure a sync endpoint
994 */
995static int sync_ep_set_params(struct snd_usb_endpoint *ep)
996{
997 int i;
998
999 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4,
1000 GFP_KERNEL, &ep->sync_dma);
1001 if (!ep->syncbuf)
1002 return -ENOMEM;
1003
1004 for (i = 0; i < SYNC_URBS; i++) {
1005 struct snd_urb_ctx *u = &ep->urb[i];
1006 u->index = i;
1007 u->ep = ep;
1008 u->packets = 1;
1009 u->urb = usb_alloc_urb(1, GFP_KERNEL);
1010 if (!u->urb)
1011 goto out_of_memory;
1012 u->urb->transfer_buffer = ep->syncbuf + i * 4;
1013 u->urb->transfer_dma = ep->sync_dma + i * 4;
1014 u->urb->transfer_buffer_length = 4;
1015 u->urb->pipe = ep->pipe;
1016 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1017 u->urb->number_of_packets = 1;
1018 u->urb->interval = 1 << ep->syncinterval;
1019 u->urb->context = u;
1020 u->urb->complete = snd_complete_urb;
1021 }
1022
1023 ep->nurbs = SYNC_URBS;
1024
1025 return 0;
1026
1027out_of_memory:
1028 release_urbs(ep, 0);
1029 return -ENOMEM;
1030}
1031
1032/**
1033 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
1034 *
1035 * @ep: the snd_usb_endpoint to configure
1036 * @pcm_format: the audio fomat.
1037 * @channels: the number of audio channels.
1038 * @period_bytes: the number of bytes in one alsa period.
1039 * @period_frames: the number of frames in one alsa period.
1040 * @buffer_periods: the number of periods in one alsa buffer.
1041 * @rate: the frame rate.
1042 * @fmt: the USB audio format information
1043 * @sync_ep: the sync endpoint to use, if any
1044 *
1045 * Determine the number of URBs to be used on this endpoint.
1046 * An endpoint must be configured before it can be started.
1047 * An endpoint that is already running can not be reconfigured.
1048 */
1049int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
1050 snd_pcm_format_t pcm_format,
1051 unsigned int channels,
1052 unsigned int period_bytes,
1053 unsigned int period_frames,
1054 unsigned int buffer_periods,
1055 unsigned int rate,
1056 struct audioformat *fmt,
1057 struct snd_usb_endpoint *sync_ep)
1058{
1059 int err;
1060
1061 if (ep->use_count != 0) {
1062 bool check = ep->is_implicit_feedback &&
1063 check_ep_params(ep, pcm_format,
1064 channels, period_bytes,
1065 period_frames, buffer_periods,
1066 fmt, sync_ep);
1067
1068 if (!check) {
1069 usb_audio_warn(ep->chip,
1070 "Unable to change format on ep #%x: already in use\n",
1071 ep->ep_num);
1072 return -EBUSY;
1073 }
1074
1075 usb_audio_dbg(ep->chip,
1076 "Ep #%x already in use as implicit feedback but format not changed\n",
1077 ep->ep_num);
1078 return 0;
1079 }
1080
1081 /* release old buffers, if any */
1082 release_urbs(ep, 0);
1083
1084 ep->datainterval = fmt->datainterval;
1085 ep->maxpacksize = fmt->maxpacksize;
1086 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
1087
1088 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL) {
1089 ep->freqn = get_usb_full_speed_rate(rate);
1090 ep->pps = 1000 >> ep->datainterval;
1091 } else {
1092 ep->freqn = get_usb_high_speed_rate(rate);
1093 ep->pps = 8000 >> ep->datainterval;
1094 }
1095
1096 ep->sample_rem = rate % ep->pps;
1097 ep->packsize[0] = rate / ep->pps;
1098 ep->packsize[1] = (rate + (ep->pps - 1)) / ep->pps;
1099
1100 /* calculate the frequency in 16.16 format */
1101 ep->freqm = ep->freqn;
1102 ep->freqshift = INT_MIN;
1103
1104 ep->phase = 0;
1105
1106 switch (ep->type) {
1107 case SND_USB_ENDPOINT_TYPE_DATA:
1108 err = data_ep_set_params(ep, pcm_format, channels,
1109 period_bytes, period_frames,
1110 buffer_periods, fmt, sync_ep);
1111 break;
1112 case SND_USB_ENDPOINT_TYPE_SYNC:
1113 err = sync_ep_set_params(ep);
1114 break;
1115 default:
1116 err = -EINVAL;
1117 }
1118
1119 usb_audio_dbg(ep->chip,
1120 "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
1121 ep->ep_num, ep->type, ep->nurbs, err);
1122
1123 return err;
1124}
1125
1126/**
1127 * snd_usb_endpoint_start: start an snd_usb_endpoint
1128 *
1129 * @ep: the endpoint to start
1130 *
1131 * A call to this function will increment the use count of the endpoint.
1132 * In case it is not already running, the URBs for this endpoint will be
1133 * submitted. Otherwise, this function does nothing.
1134 *
1135 * Must be balanced to calls of snd_usb_endpoint_stop().
1136 *
1137 * Returns an error if the URB submission failed, 0 in all other cases.
1138 */
1139int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
1140{
1141 int err;
1142 unsigned int i;
1143
1144 if (atomic_read(&ep->chip->shutdown))
1145 return -EBADFD;
1146
1147 /* already running? */
1148 if (++ep->use_count != 1)
1149 return 0;
1150
1151 /* just to be sure */
1152 deactivate_urbs(ep, false);
1153
1154 ep->active_mask = 0;
1155 ep->unlink_mask = 0;
1156 ep->phase = 0;
1157 ep->sample_accum = 0;
1158
1159 snd_usb_endpoint_start_quirk(ep);
1160
1161 /*
1162 * If this endpoint has a data endpoint as implicit feedback source,
1163 * don't start the urbs here. Instead, mark them all as available,
1164 * wait for the record urbs to return and queue the playback urbs
1165 * from that context.
1166 */
1167
1168 set_bit(EP_FLAG_RUNNING, &ep->flags);
1169
1170 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
1171 for (i = 0; i < ep->nurbs; i++) {
1172 struct snd_urb_ctx *ctx = ep->urb + i;
1173 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
1174 }
1175
1176 return 0;
1177 }
1178
1179 for (i = 0; i < ep->nurbs; i++) {
1180 struct urb *urb = ep->urb[i].urb;
1181
1182 if (snd_BUG_ON(!urb))
1183 goto __error;
1184
1185 if (usb_pipeout(ep->pipe)) {
1186 prepare_outbound_urb(ep, urb->context);
1187 } else {
1188 prepare_inbound_urb(ep, urb->context);
1189 }
1190
1191 err = usb_submit_urb(urb, GFP_ATOMIC);
1192 if (err < 0) {
1193 usb_audio_err(ep->chip,
1194 "cannot submit urb %d, error %d: %s\n",
1195 i, err, usb_error_string(err));
1196 goto __error;
1197 }
1198 set_bit(i, &ep->active_mask);
1199 }
1200
1201 return 0;
1202
1203__error:
1204 clear_bit(EP_FLAG_RUNNING, &ep->flags);
1205 ep->use_count--;
1206 deactivate_urbs(ep, false);
1207 return -EPIPE;
1208}
1209
1210/**
1211 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
1212 *
1213 * @ep: the endpoint to stop (may be NULL)
1214 *
1215 * A call to this function will decrement the use count of the endpoint.
1216 * In case the last user has requested the endpoint stop, the URBs will
1217 * actually be deactivated.
1218 *
1219 * Must be balanced to calls of snd_usb_endpoint_start().
1220 *
1221 * The caller needs to synchronize the pending stop operation via
1222 * snd_usb_endpoint_sync_pending_stop().
1223 */
1224void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep)
1225{
1226 if (!ep)
1227 return;
1228
1229 if (snd_BUG_ON(ep->use_count == 0))
1230 return;
1231
1232 if (--ep->use_count == 0) {
1233 deactivate_urbs(ep, false);
1234 set_bit(EP_FLAG_STOPPING, &ep->flags);
1235 }
1236}
1237
1238/**
1239 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
1240 *
1241 * @ep: the endpoint to deactivate
1242 *
1243 * If the endpoint is not currently in use, this functions will
1244 * deactivate its associated URBs.
1245 *
1246 * In case of any active users, this functions does nothing.
1247 */
1248void snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep)
1249{
1250 if (!ep)
1251 return;
1252
1253 if (ep->use_count != 0)
1254 return;
1255
1256 deactivate_urbs(ep, true);
1257 wait_clear_urbs(ep);
1258}
1259
1260/**
1261 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1262 *
1263 * @ep: the endpoint to release
1264 *
1265 * This function does not care for the endpoint's use count but will tear
1266 * down all the streaming URBs immediately.
1267 */
1268void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1269{
1270 release_urbs(ep, 1);
1271}
1272
1273/**
1274 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
1275 *
1276 * @ep: the endpoint to free
1277 *
1278 * This free all resources of the given ep.
1279 */
1280void snd_usb_endpoint_free(struct snd_usb_endpoint *ep)
1281{
1282 kfree(ep);
1283}
1284
1285/**
1286 * snd_usb_handle_sync_urb: parse an USB sync packet
1287 *
1288 * @ep: the endpoint to handle the packet
1289 * @sender: the sending endpoint
1290 * @urb: the received packet
1291 *
1292 * This function is called from the context of an endpoint that received
1293 * the packet and is used to let another endpoint object handle the payload.
1294 */
1295void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1296 struct snd_usb_endpoint *sender,
1297 const struct urb *urb)
1298{
1299 int shift;
1300 unsigned int f;
1301 unsigned long flags;
1302
1303 snd_BUG_ON(ep == sender);
1304
1305 /*
1306 * In case the endpoint is operating in implicit feedback mode, prepare
1307 * a new outbound URB that has the same layout as the received packet
1308 * and add it to the list of pending urbs. queue_pending_output_urbs()
1309 * will take care of them later.
1310 */
1311 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1312 ep->use_count != 0) {
1313
1314 /* implicit feedback case */
1315 int i, bytes = 0;
1316 struct snd_urb_ctx *in_ctx;
1317 struct snd_usb_packet_info *out_packet;
1318
1319 in_ctx = urb->context;
1320
1321 /* Count overall packet size */
1322 for (i = 0; i < in_ctx->packets; i++)
1323 if (urb->iso_frame_desc[i].status == 0)
1324 bytes += urb->iso_frame_desc[i].actual_length;
1325
1326 /*
1327 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1328 * streaming once it received a 0-byte OUT URB
1329 */
1330 if (bytes == 0)
1331 return;
1332
1333 spin_lock_irqsave(&ep->lock, flags);
1334 out_packet = ep->next_packet + ep->next_packet_write_pos;
1335
1336 /*
1337 * Iterate through the inbound packet and prepare the lengths
1338 * for the output packet. The OUT packet we are about to send
1339 * will have the same amount of payload bytes per stride as the
1340 * IN packet we just received. Since the actual size is scaled
1341 * by the stride, use the sender stride to calculate the length
1342 * in case the number of channels differ between the implicitly
1343 * fed-back endpoint and the synchronizing endpoint.
1344 */
1345
1346 out_packet->packets = in_ctx->packets;
1347 for (i = 0; i < in_ctx->packets; i++) {
1348 if (urb->iso_frame_desc[i].status == 0)
1349 out_packet->packet_size[i] =
1350 urb->iso_frame_desc[i].actual_length / sender->stride;
1351 else
1352 out_packet->packet_size[i] = 0;
1353 }
1354
1355 ep->next_packet_write_pos++;
1356 ep->next_packet_write_pos %= MAX_URBS;
1357 spin_unlock_irqrestore(&ep->lock, flags);
1358 queue_pending_output_urbs(ep);
1359
1360 return;
1361 }
1362
1363 /*
1364 * process after playback sync complete
1365 *
1366 * Full speed devices report feedback values in 10.14 format as samples
1367 * per frame, high speed devices in 16.16 format as samples per
1368 * microframe.
1369 *
1370 * Because the Audio Class 1 spec was written before USB 2.0, many high
1371 * speed devices use a wrong interpretation, some others use an
1372 * entirely different format.
1373 *
1374 * Therefore, we cannot predict what format any particular device uses
1375 * and must detect it automatically.
1376 */
1377
1378 if (urb->iso_frame_desc[0].status != 0 ||
1379 urb->iso_frame_desc[0].actual_length < 3)
1380 return;
1381
1382 f = le32_to_cpup(urb->transfer_buffer);
1383 if (urb->iso_frame_desc[0].actual_length == 3)
1384 f &= 0x00ffffff;
1385 else
1386 f &= 0x0fffffff;
1387
1388 if (f == 0)
1389 return;
1390
1391 if (unlikely(sender->tenor_fb_quirk)) {
1392 /*
1393 * Devices based on Tenor 8802 chipsets (TEAC UD-H01
1394 * and others) sometimes change the feedback value
1395 * by +/- 0x1.0000.
1396 */
1397 if (f < ep->freqn - 0x8000)
1398 f += 0xf000;
1399 else if (f > ep->freqn + 0x8000)
1400 f -= 0xf000;
1401 } else if (unlikely(ep->freqshift == INT_MIN)) {
1402 /*
1403 * The first time we see a feedback value, determine its format
1404 * by shifting it left or right until it matches the nominal
1405 * frequency value. This assumes that the feedback does not
1406 * differ from the nominal value more than +50% or -25%.
1407 */
1408 shift = 0;
1409 while (f < ep->freqn - ep->freqn / 4) {
1410 f <<= 1;
1411 shift++;
1412 }
1413 while (f > ep->freqn + ep->freqn / 2) {
1414 f >>= 1;
1415 shift--;
1416 }
1417 ep->freqshift = shift;
1418 } else if (ep->freqshift >= 0)
1419 f <<= ep->freqshift;
1420 else
1421 f >>= -ep->freqshift;
1422
1423 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1424 /*
1425 * If the frequency looks valid, set it.
1426 * This value is referred to in prepare_playback_urb().
1427 */
1428 spin_lock_irqsave(&ep->lock, flags);
1429 ep->freqm = f;
1430 spin_unlock_irqrestore(&ep->lock, flags);
1431 } else {
1432 /*
1433 * Out of range; maybe the shift value is wrong.
1434 * Reset it so that we autodetect again the next time.
1435 */
1436 ep->freqshift = INT_MIN;
1437 }
1438}
1439
1/*
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
186static void prepare_silent_urb(struct snd_usb_endpoint *ep,
187 struct snd_urb_ctx *ctx)
188{
189 struct urb *urb = ctx->urb;
190 unsigned int offs = 0;
191 unsigned int extra = 0;
192 __le32 packet_length;
193 int i;
194
195 /* For tx_length_quirk, put packet length at start of packet */
196 if (ep->chip->tx_length_quirk)
197 extra = sizeof(packet_length);
198
199 for (i = 0; i < ctx->packets; ++i) {
200 unsigned int offset;
201 unsigned int length;
202 int counts;
203
204 if (ctx->packet_size[i])
205 counts = ctx->packet_size[i];
206 else
207 counts = snd_usb_endpoint_next_packet_size(ep);
208
209 length = counts * ep->stride; /* number of silent bytes */
210 offset = offs * ep->stride + extra * i;
211 urb->iso_frame_desc[i].offset = offset;
212 urb->iso_frame_desc[i].length = length + extra;
213 if (extra) {
214 packet_length = cpu_to_le32(length);
215 memcpy(urb->transfer_buffer + offset,
216 &packet_length, sizeof(packet_length));
217 }
218 memset(urb->transfer_buffer + offset + extra,
219 ep->silence_value, length);
220 offs += counts;
221 }
222
223 urb->number_of_packets = ctx->packets;
224 urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
225}
226
227/*
228 * Prepare a PLAYBACK urb for submission to the bus.
229 */
230static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
231 struct snd_urb_ctx *ctx)
232{
233 struct urb *urb = ctx->urb;
234 unsigned char *cp = urb->transfer_buffer;
235
236 urb->dev = ep->chip->dev; /* we need to set this at each time */
237
238 switch (ep->type) {
239 case SND_USB_ENDPOINT_TYPE_DATA:
240 if (ep->prepare_data_urb) {
241 ep->prepare_data_urb(ep->data_subs, urb);
242 } else {
243 /* no data provider, so send silence */
244 prepare_silent_urb(ep, ctx);
245 }
246 break;
247
248 case SND_USB_ENDPOINT_TYPE_SYNC:
249 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
250 /*
251 * fill the length and offset of each urb descriptor.
252 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
253 */
254 urb->iso_frame_desc[0].length = 4;
255 urb->iso_frame_desc[0].offset = 0;
256 cp[0] = ep->freqn;
257 cp[1] = ep->freqn >> 8;
258 cp[2] = ep->freqn >> 16;
259 cp[3] = ep->freqn >> 24;
260 } else {
261 /*
262 * fill the length and offset of each urb descriptor.
263 * the fixed 10.14 frequency is passed through the pipe.
264 */
265 urb->iso_frame_desc[0].length = 3;
266 urb->iso_frame_desc[0].offset = 0;
267 cp[0] = ep->freqn >> 2;
268 cp[1] = ep->freqn >> 10;
269 cp[2] = ep->freqn >> 18;
270 }
271
272 break;
273 }
274}
275
276/*
277 * Prepare a CAPTURE or SYNC urb for submission to the bus.
278 */
279static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep,
280 struct snd_urb_ctx *urb_ctx)
281{
282 int i, offs;
283 struct urb *urb = urb_ctx->urb;
284
285 urb->dev = ep->chip->dev; /* we need to set this at each time */
286
287 switch (ep->type) {
288 case SND_USB_ENDPOINT_TYPE_DATA:
289 offs = 0;
290 for (i = 0; i < urb_ctx->packets; i++) {
291 urb->iso_frame_desc[i].offset = offs;
292 urb->iso_frame_desc[i].length = ep->curpacksize;
293 offs += ep->curpacksize;
294 }
295
296 urb->transfer_buffer_length = offs;
297 urb->number_of_packets = urb_ctx->packets;
298 break;
299
300 case SND_USB_ENDPOINT_TYPE_SYNC:
301 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
302 urb->iso_frame_desc[0].offset = 0;
303 break;
304 }
305}
306
307/*
308 * Send output urbs that have been prepared previously. URBs are dequeued
309 * from ep->ready_playback_urbs and in case there there aren't any available
310 * or there are no packets that have been prepared, this function does
311 * nothing.
312 *
313 * The reason why the functionality of sending and preparing URBs is separated
314 * is that host controllers don't guarantee the order in which they return
315 * inbound and outbound packets to their submitters.
316 *
317 * This function is only used for implicit feedback endpoints. For endpoints
318 * driven by dedicated sync endpoints, URBs are immediately re-submitted
319 * from their completion handler.
320 */
321static void queue_pending_output_urbs(struct snd_usb_endpoint *ep)
322{
323 while (test_bit(EP_FLAG_RUNNING, &ep->flags)) {
324
325 unsigned long flags;
326 struct snd_usb_packet_info *uninitialized_var(packet);
327 struct snd_urb_ctx *ctx = NULL;
328 struct urb *urb;
329 int err, i;
330
331 spin_lock_irqsave(&ep->lock, flags);
332 if (ep->next_packet_read_pos != ep->next_packet_write_pos) {
333 packet = ep->next_packet + ep->next_packet_read_pos;
334 ep->next_packet_read_pos++;
335 ep->next_packet_read_pos %= MAX_URBS;
336
337 /* take URB out of FIFO */
338 if (!list_empty(&ep->ready_playback_urbs))
339 ctx = list_first_entry(&ep->ready_playback_urbs,
340 struct snd_urb_ctx, ready_list);
341 }
342 spin_unlock_irqrestore(&ep->lock, flags);
343
344 if (ctx == NULL)
345 return;
346
347 list_del_init(&ctx->ready_list);
348 urb = ctx->urb;
349
350 /* copy over the length information */
351 for (i = 0; i < packet->packets; i++)
352 ctx->packet_size[i] = packet->packet_size[i];
353
354 /* call the data handler to fill in playback data */
355 prepare_outbound_urb(ep, ctx);
356
357 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
358 if (err < 0)
359 usb_audio_err(ep->chip,
360 "Unable to submit urb #%d: %d (urb %p)\n",
361 ctx->index, err, ctx->urb);
362 else
363 set_bit(ctx->index, &ep->active_mask);
364 }
365}
366
367/*
368 * complete callback for urbs
369 */
370static void snd_complete_urb(struct urb *urb)
371{
372 struct snd_urb_ctx *ctx = urb->context;
373 struct snd_usb_endpoint *ep = ctx->ep;
374 struct snd_pcm_substream *substream;
375 unsigned long flags;
376 int err;
377
378 if (unlikely(urb->status == -ENOENT || /* unlinked */
379 urb->status == -ENODEV || /* device removed */
380 urb->status == -ECONNRESET || /* unlinked */
381 urb->status == -ESHUTDOWN)) /* device disabled */
382 goto exit_clear;
383 /* device disconnected */
384 if (unlikely(atomic_read(&ep->chip->shutdown)))
385 goto exit_clear;
386
387 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
388 goto exit_clear;
389
390 if (usb_pipeout(ep->pipe)) {
391 retire_outbound_urb(ep, ctx);
392 /* can be stopped during retire callback */
393 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
394 goto exit_clear;
395
396 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
397 spin_lock_irqsave(&ep->lock, flags);
398 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
399 spin_unlock_irqrestore(&ep->lock, flags);
400 queue_pending_output_urbs(ep);
401
402 goto exit_clear;
403 }
404
405 prepare_outbound_urb(ep, ctx);
406 } else {
407 retire_inbound_urb(ep, ctx);
408 /* can be stopped during retire callback */
409 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
410 goto exit_clear;
411
412 prepare_inbound_urb(ep, ctx);
413 }
414
415 err = usb_submit_urb(urb, GFP_ATOMIC);
416 if (err == 0)
417 return;
418
419 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
420 if (ep->data_subs && ep->data_subs->pcm_substream) {
421 substream = ep->data_subs->pcm_substream;
422 snd_pcm_stop_xrun(substream);
423 }
424
425exit_clear:
426 clear_bit(ctx->index, &ep->active_mask);
427}
428
429/**
430 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
431 *
432 * @chip: The chip
433 * @alts: The USB host interface
434 * @ep_num: The number of the endpoint to use
435 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
436 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
437 *
438 * If the requested endpoint has not been added to the given chip before,
439 * a new instance is created. Otherwise, a pointer to the previoulsy
440 * created instance is returned. In case of any error, NULL is returned.
441 *
442 * New endpoints will be added to chip->ep_list and must be freed by
443 * calling snd_usb_endpoint_free().
444 *
445 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
446 * bNumEndpoints > 1 beforehand.
447 */
448struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
449 struct usb_host_interface *alts,
450 int ep_num, int direction, int type)
451{
452 struct snd_usb_endpoint *ep;
453 int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK;
454
455 if (WARN_ON(!alts))
456 return NULL;
457
458 mutex_lock(&chip->mutex);
459
460 list_for_each_entry(ep, &chip->ep_list, list) {
461 if (ep->ep_num == ep_num &&
462 ep->iface == alts->desc.bInterfaceNumber &&
463 ep->altsetting == alts->desc.bAlternateSetting) {
464 usb_audio_dbg(ep->chip,
465 "Re-using EP %x in iface %d,%d @%p\n",
466 ep_num, ep->iface, ep->altsetting, ep);
467 goto __exit_unlock;
468 }
469 }
470
471 usb_audio_dbg(chip, "Creating new %s %s endpoint #%x\n",
472 is_playback ? "playback" : "capture",
473 type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync",
474 ep_num);
475
476 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
477 if (!ep)
478 goto __exit_unlock;
479
480 ep->chip = chip;
481 spin_lock_init(&ep->lock);
482 ep->type = type;
483 ep->ep_num = ep_num;
484 ep->iface = alts->desc.bInterfaceNumber;
485 ep->altsetting = alts->desc.bAlternateSetting;
486 INIT_LIST_HEAD(&ep->ready_playback_urbs);
487 ep_num &= USB_ENDPOINT_NUMBER_MASK;
488
489 if (is_playback)
490 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
491 else
492 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
493
494 if (type == SND_USB_ENDPOINT_TYPE_SYNC) {
495 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
496 get_endpoint(alts, 1)->bRefresh >= 1 &&
497 get_endpoint(alts, 1)->bRefresh <= 9)
498 ep->syncinterval = get_endpoint(alts, 1)->bRefresh;
499 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
500 ep->syncinterval = 1;
501 else if (get_endpoint(alts, 1)->bInterval >= 1 &&
502 get_endpoint(alts, 1)->bInterval <= 16)
503 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1;
504 else
505 ep->syncinterval = 3;
506
507 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize);
508 }
509
510 list_add_tail(&ep->list, &chip->ep_list);
511
512__exit_unlock:
513 mutex_unlock(&chip->mutex);
514
515 return ep;
516}
517
518/*
519 * wait until all urbs are processed.
520 */
521static int wait_clear_urbs(struct snd_usb_endpoint *ep)
522{
523 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
524 int alive;
525
526 do {
527 alive = bitmap_weight(&ep->active_mask, ep->nurbs);
528 if (!alive)
529 break;
530
531 schedule_timeout_uninterruptible(1);
532 } while (time_before(jiffies, end_time));
533
534 if (alive)
535 usb_audio_err(ep->chip,
536 "timeout: still %d active urbs on EP #%x\n",
537 alive, ep->ep_num);
538 clear_bit(EP_FLAG_STOPPING, &ep->flags);
539
540 ep->data_subs = NULL;
541 ep->sync_slave = NULL;
542 ep->retire_data_urb = NULL;
543 ep->prepare_data_urb = NULL;
544
545 return 0;
546}
547
548/* sync the pending stop operation;
549 * this function itself doesn't trigger the stop operation
550 */
551void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
552{
553 if (ep && test_bit(EP_FLAG_STOPPING, &ep->flags))
554 wait_clear_urbs(ep);
555}
556
557/*
558 * unlink active urbs.
559 */
560static int deactivate_urbs(struct snd_usb_endpoint *ep, bool force)
561{
562 unsigned int i;
563
564 if (!force && atomic_read(&ep->chip->shutdown)) /* to be sure... */
565 return -EBADFD;
566
567 clear_bit(EP_FLAG_RUNNING, &ep->flags);
568
569 INIT_LIST_HEAD(&ep->ready_playback_urbs);
570 ep->next_packet_read_pos = 0;
571 ep->next_packet_write_pos = 0;
572
573 for (i = 0; i < ep->nurbs; i++) {
574 if (test_bit(i, &ep->active_mask)) {
575 if (!test_and_set_bit(i, &ep->unlink_mask)) {
576 struct urb *u = ep->urb[i].urb;
577 usb_unlink_urb(u);
578 }
579 }
580 }
581
582 return 0;
583}
584
585/*
586 * release an endpoint's urbs
587 */
588static void release_urbs(struct snd_usb_endpoint *ep, int force)
589{
590 int i;
591
592 /* route incoming urbs to nirvana */
593 ep->retire_data_urb = NULL;
594 ep->prepare_data_urb = NULL;
595
596 /* stop urbs */
597 deactivate_urbs(ep, force);
598 wait_clear_urbs(ep);
599
600 for (i = 0; i < ep->nurbs; i++)
601 release_urb_ctx(&ep->urb[i]);
602
603 if (ep->syncbuf)
604 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
605 ep->syncbuf, ep->sync_dma);
606
607 ep->syncbuf = NULL;
608 ep->nurbs = 0;
609}
610
611/*
612 * configure a data endpoint
613 */
614static int data_ep_set_params(struct snd_usb_endpoint *ep,
615 snd_pcm_format_t pcm_format,
616 unsigned int channels,
617 unsigned int period_bytes,
618 unsigned int frames_per_period,
619 unsigned int periods_per_buffer,
620 struct audioformat *fmt,
621 struct snd_usb_endpoint *sync_ep)
622{
623 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
624 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
625 unsigned int max_urbs, i;
626 int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels;
627 int tx_length_quirk = (ep->chip->tx_length_quirk &&
628 usb_pipeout(ep->pipe));
629
630 if (pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
631 /*
632 * When operating in DSD DOP mode, the size of a sample frame
633 * in hardware differs from the actual physical format width
634 * because we need to make room for the DOP markers.
635 */
636 frame_bits += channels << 3;
637 }
638
639 ep->datainterval = fmt->datainterval;
640 ep->stride = frame_bits >> 3;
641
642 switch (pcm_format) {
643 case SNDRV_PCM_FORMAT_U8:
644 ep->silence_value = 0x80;
645 break;
646 case SNDRV_PCM_FORMAT_DSD_U8:
647 case SNDRV_PCM_FORMAT_DSD_U16_LE:
648 case SNDRV_PCM_FORMAT_DSD_U32_LE:
649 case SNDRV_PCM_FORMAT_DSD_U16_BE:
650 case SNDRV_PCM_FORMAT_DSD_U32_BE:
651 ep->silence_value = 0x69;
652 break;
653 default:
654 ep->silence_value = 0;
655 }
656
657 /* assume max. frequency is 50% higher than nominal */
658 ep->freqmax = ep->freqn + (ep->freqn >> 1);
659 /* Round up freqmax to nearest integer in order to calculate maximum
660 * packet size, which must represent a whole number of frames.
661 * This is accomplished by adding 0x0.ffff before converting the
662 * Q16.16 format into integer.
663 * In order to accurately calculate the maximum packet size when
664 * the data interval is more than 1 (i.e. ep->datainterval > 0),
665 * multiply by the data interval prior to rounding. For instance,
666 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
667 * frames with a data interval of 1, but 11 (10.25) frames with a
668 * data interval of 2.
669 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
670 * maximum datainterval value of 3, at USB full speed, higher for
671 * USB high speed, noting that ep->freqmax is in units of
672 * frames per packet in Q16.16 format.)
673 */
674 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
675 (frame_bits >> 3);
676 if (tx_length_quirk)
677 maxsize += sizeof(__le32); /* Space for length descriptor */
678 /* but wMaxPacketSize might reduce this */
679 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
680 /* whatever fits into a max. size packet */
681 unsigned int data_maxsize = maxsize = ep->maxpacksize;
682
683 if (tx_length_quirk)
684 /* Need to remove the length descriptor to calc freq */
685 data_maxsize -= sizeof(__le32);
686 ep->freqmax = (data_maxsize / (frame_bits >> 3))
687 << (16 - ep->datainterval);
688 }
689
690 if (ep->fill_max)
691 ep->curpacksize = ep->maxpacksize;
692 else
693 ep->curpacksize = maxsize;
694
695 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) {
696 packs_per_ms = 8 >> ep->datainterval;
697 max_packs_per_urb = MAX_PACKS_HS;
698 } else {
699 packs_per_ms = 1;
700 max_packs_per_urb = MAX_PACKS;
701 }
702 if (sync_ep && !snd_usb_endpoint_implicit_feedback_sink(ep))
703 max_packs_per_urb = min(max_packs_per_urb,
704 1U << sync_ep->syncinterval);
705 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
706
707 /*
708 * Capture endpoints need to use small URBs because there's no way
709 * to tell in advance where the next period will end, and we don't
710 * want the next URB to complete much after the period ends.
711 *
712 * Playback endpoints with implicit sync much use the same parameters
713 * as their corresponding capture endpoint.
714 */
715 if (usb_pipein(ep->pipe) ||
716 snd_usb_endpoint_implicit_feedback_sink(ep)) {
717
718 urb_packs = packs_per_ms;
719 /*
720 * Wireless devices can poll at a max rate of once per 4ms.
721 * For dataintervals less than 5, increase the packet count to
722 * allow the host controller to use bursting to fill in the
723 * gaps.
724 */
725 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_WIRELESS) {
726 int interval = ep->datainterval;
727 while (interval < 5) {
728 urb_packs <<= 1;
729 ++interval;
730 }
731 }
732 /* make capture URBs <= 1 ms and smaller than a period */
733 urb_packs = min(max_packs_per_urb, urb_packs);
734 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
735 urb_packs >>= 1;
736 ep->nurbs = MAX_URBS;
737
738 /*
739 * Playback endpoints without implicit sync are adjusted so that
740 * a period fits as evenly as possible in the smallest number of
741 * URBs. The total number of URBs is adjusted to the size of the
742 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
743 */
744 } else {
745 /* determine how small a packet can be */
746 minsize = (ep->freqn >> (16 - ep->datainterval)) *
747 (frame_bits >> 3);
748 /* with sync from device, assume it can be 12% lower */
749 if (sync_ep)
750 minsize -= minsize >> 3;
751 minsize = max(minsize, 1u);
752
753 /* how many packets will contain an entire ALSA period? */
754 max_packs_per_period = DIV_ROUND_UP(period_bytes, minsize);
755
756 /* how many URBs will contain a period? */
757 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
758 max_packs_per_urb);
759 /* how many packets are needed in each URB? */
760 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
761
762 /* limit the number of frames in a single URB */
763 ep->max_urb_frames = DIV_ROUND_UP(frames_per_period,
764 urbs_per_period);
765
766 /* try to use enough URBs to contain an entire ALSA buffer */
767 max_urbs = min((unsigned) MAX_URBS,
768 MAX_QUEUE * packs_per_ms / urb_packs);
769 ep->nurbs = min(max_urbs, urbs_per_period * periods_per_buffer);
770 }
771
772 /* allocate and initialize data urbs */
773 for (i = 0; i < ep->nurbs; i++) {
774 struct snd_urb_ctx *u = &ep->urb[i];
775 u->index = i;
776 u->ep = ep;
777 u->packets = urb_packs;
778 u->buffer_size = maxsize * u->packets;
779
780 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
781 u->packets++; /* for transfer delimiter */
782 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
783 if (!u->urb)
784 goto out_of_memory;
785
786 u->urb->transfer_buffer =
787 usb_alloc_coherent(ep->chip->dev, u->buffer_size,
788 GFP_KERNEL, &u->urb->transfer_dma);
789 if (!u->urb->transfer_buffer)
790 goto out_of_memory;
791 u->urb->pipe = ep->pipe;
792 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
793 u->urb->interval = 1 << ep->datainterval;
794 u->urb->context = u;
795 u->urb->complete = snd_complete_urb;
796 INIT_LIST_HEAD(&u->ready_list);
797 }
798
799 return 0;
800
801out_of_memory:
802 release_urbs(ep, 0);
803 return -ENOMEM;
804}
805
806/*
807 * configure a sync endpoint
808 */
809static int sync_ep_set_params(struct snd_usb_endpoint *ep)
810{
811 int i;
812
813 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4,
814 GFP_KERNEL, &ep->sync_dma);
815 if (!ep->syncbuf)
816 return -ENOMEM;
817
818 for (i = 0; i < SYNC_URBS; i++) {
819 struct snd_urb_ctx *u = &ep->urb[i];
820 u->index = i;
821 u->ep = ep;
822 u->packets = 1;
823 u->urb = usb_alloc_urb(1, GFP_KERNEL);
824 if (!u->urb)
825 goto out_of_memory;
826 u->urb->transfer_buffer = ep->syncbuf + i * 4;
827 u->urb->transfer_dma = ep->sync_dma + i * 4;
828 u->urb->transfer_buffer_length = 4;
829 u->urb->pipe = ep->pipe;
830 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
831 u->urb->number_of_packets = 1;
832 u->urb->interval = 1 << ep->syncinterval;
833 u->urb->context = u;
834 u->urb->complete = snd_complete_urb;
835 }
836
837 ep->nurbs = SYNC_URBS;
838
839 return 0;
840
841out_of_memory:
842 release_urbs(ep, 0);
843 return -ENOMEM;
844}
845
846/**
847 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
848 *
849 * @ep: the snd_usb_endpoint to configure
850 * @pcm_format: the audio fomat.
851 * @channels: the number of audio channels.
852 * @period_bytes: the number of bytes in one alsa period.
853 * @period_frames: the number of frames in one alsa period.
854 * @buffer_periods: the number of periods in one alsa buffer.
855 * @rate: the frame rate.
856 * @fmt: the USB audio format information
857 * @sync_ep: the sync endpoint to use, if any
858 *
859 * Determine the number of URBs to be used on this endpoint.
860 * An endpoint must be configured before it can be started.
861 * An endpoint that is already running can not be reconfigured.
862 */
863int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
864 snd_pcm_format_t pcm_format,
865 unsigned int channels,
866 unsigned int period_bytes,
867 unsigned int period_frames,
868 unsigned int buffer_periods,
869 unsigned int rate,
870 struct audioformat *fmt,
871 struct snd_usb_endpoint *sync_ep)
872{
873 int err;
874
875 if (ep->use_count != 0) {
876 usb_audio_warn(ep->chip,
877 "Unable to change format on ep #%x: already in use\n",
878 ep->ep_num);
879 return -EBUSY;
880 }
881
882 /* release old buffers, if any */
883 release_urbs(ep, 0);
884
885 ep->datainterval = fmt->datainterval;
886 ep->maxpacksize = fmt->maxpacksize;
887 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
888
889 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL)
890 ep->freqn = get_usb_full_speed_rate(rate);
891 else
892 ep->freqn = get_usb_high_speed_rate(rate);
893
894 /* calculate the frequency in 16.16 format */
895 ep->freqm = ep->freqn;
896 ep->freqshift = INT_MIN;
897
898 ep->phase = 0;
899
900 switch (ep->type) {
901 case SND_USB_ENDPOINT_TYPE_DATA:
902 err = data_ep_set_params(ep, pcm_format, channels,
903 period_bytes, period_frames,
904 buffer_periods, fmt, sync_ep);
905 break;
906 case SND_USB_ENDPOINT_TYPE_SYNC:
907 err = sync_ep_set_params(ep);
908 break;
909 default:
910 err = -EINVAL;
911 }
912
913 usb_audio_dbg(ep->chip,
914 "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
915 ep->ep_num, ep->type, ep->nurbs, err);
916
917 return err;
918}
919
920/**
921 * snd_usb_endpoint_start: start an snd_usb_endpoint
922 *
923 * @ep: the endpoint to start
924 *
925 * A call to this function will increment the use count of the endpoint.
926 * In case it is not already running, the URBs for this endpoint will be
927 * submitted. Otherwise, this function does nothing.
928 *
929 * Must be balanced to calls of snd_usb_endpoint_stop().
930 *
931 * Returns an error if the URB submission failed, 0 in all other cases.
932 */
933int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
934{
935 int err;
936 unsigned int i;
937
938 if (atomic_read(&ep->chip->shutdown))
939 return -EBADFD;
940
941 /* already running? */
942 if (++ep->use_count != 1)
943 return 0;
944
945 /* just to be sure */
946 deactivate_urbs(ep, false);
947
948 ep->active_mask = 0;
949 ep->unlink_mask = 0;
950 ep->phase = 0;
951
952 snd_usb_endpoint_start_quirk(ep);
953
954 /*
955 * If this endpoint has a data endpoint as implicit feedback source,
956 * don't start the urbs here. Instead, mark them all as available,
957 * wait for the record urbs to return and queue the playback urbs
958 * from that context.
959 */
960
961 set_bit(EP_FLAG_RUNNING, &ep->flags);
962
963 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
964 for (i = 0; i < ep->nurbs; i++) {
965 struct snd_urb_ctx *ctx = ep->urb + i;
966 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
967 }
968
969 return 0;
970 }
971
972 for (i = 0; i < ep->nurbs; i++) {
973 struct urb *urb = ep->urb[i].urb;
974
975 if (snd_BUG_ON(!urb))
976 goto __error;
977
978 if (usb_pipeout(ep->pipe)) {
979 prepare_outbound_urb(ep, urb->context);
980 } else {
981 prepare_inbound_urb(ep, urb->context);
982 }
983
984 err = usb_submit_urb(urb, GFP_ATOMIC);
985 if (err < 0) {
986 usb_audio_err(ep->chip,
987 "cannot submit urb %d, error %d: %s\n",
988 i, err, usb_error_string(err));
989 goto __error;
990 }
991 set_bit(i, &ep->active_mask);
992 }
993
994 return 0;
995
996__error:
997 clear_bit(EP_FLAG_RUNNING, &ep->flags);
998 ep->use_count--;
999 deactivate_urbs(ep, false);
1000 return -EPIPE;
1001}
1002
1003/**
1004 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
1005 *
1006 * @ep: the endpoint to stop (may be NULL)
1007 *
1008 * A call to this function will decrement the use count of the endpoint.
1009 * In case the last user has requested the endpoint stop, the URBs will
1010 * actually be deactivated.
1011 *
1012 * Must be balanced to calls of snd_usb_endpoint_start().
1013 *
1014 * The caller needs to synchronize the pending stop operation via
1015 * snd_usb_endpoint_sync_pending_stop().
1016 */
1017void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep)
1018{
1019 if (!ep)
1020 return;
1021
1022 if (snd_BUG_ON(ep->use_count == 0))
1023 return;
1024
1025 if (--ep->use_count == 0) {
1026 deactivate_urbs(ep, false);
1027 set_bit(EP_FLAG_STOPPING, &ep->flags);
1028 }
1029}
1030
1031/**
1032 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
1033 *
1034 * @ep: the endpoint to deactivate
1035 *
1036 * If the endpoint is not currently in use, this functions will
1037 * deactivate its associated URBs.
1038 *
1039 * In case of any active users, this functions does nothing.
1040 */
1041void snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep)
1042{
1043 if (!ep)
1044 return;
1045
1046 if (ep->use_count != 0)
1047 return;
1048
1049 deactivate_urbs(ep, true);
1050 wait_clear_urbs(ep);
1051}
1052
1053/**
1054 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1055 *
1056 * @ep: the endpoint to release
1057 *
1058 * This function does not care for the endpoint's use count but will tear
1059 * down all the streaming URBs immediately.
1060 */
1061void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1062{
1063 release_urbs(ep, 1);
1064}
1065
1066/**
1067 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
1068 *
1069 * @ep: the endpoint to free
1070 *
1071 * This free all resources of the given ep.
1072 */
1073void snd_usb_endpoint_free(struct snd_usb_endpoint *ep)
1074{
1075 kfree(ep);
1076}
1077
1078/**
1079 * snd_usb_handle_sync_urb: parse an USB sync packet
1080 *
1081 * @ep: the endpoint to handle the packet
1082 * @sender: the sending endpoint
1083 * @urb: the received packet
1084 *
1085 * This function is called from the context of an endpoint that received
1086 * the packet and is used to let another endpoint object handle the payload.
1087 */
1088void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1089 struct snd_usb_endpoint *sender,
1090 const struct urb *urb)
1091{
1092 int shift;
1093 unsigned int f;
1094 unsigned long flags;
1095
1096 snd_BUG_ON(ep == sender);
1097
1098 /*
1099 * In case the endpoint is operating in implicit feedback mode, prepare
1100 * a new outbound URB that has the same layout as the received packet
1101 * and add it to the list of pending urbs. queue_pending_output_urbs()
1102 * will take care of them later.
1103 */
1104 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1105 ep->use_count != 0) {
1106
1107 /* implicit feedback case */
1108 int i, bytes = 0;
1109 struct snd_urb_ctx *in_ctx;
1110 struct snd_usb_packet_info *out_packet;
1111
1112 in_ctx = urb->context;
1113
1114 /* Count overall packet size */
1115 for (i = 0; i < in_ctx->packets; i++)
1116 if (urb->iso_frame_desc[i].status == 0)
1117 bytes += urb->iso_frame_desc[i].actual_length;
1118
1119 /*
1120 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1121 * streaming once it received a 0-byte OUT URB
1122 */
1123 if (bytes == 0)
1124 return;
1125
1126 spin_lock_irqsave(&ep->lock, flags);
1127 out_packet = ep->next_packet + ep->next_packet_write_pos;
1128
1129 /*
1130 * Iterate through the inbound packet and prepare the lengths
1131 * for the output packet. The OUT packet we are about to send
1132 * will have the same amount of payload bytes per stride as the
1133 * IN packet we just received. Since the actual size is scaled
1134 * by the stride, use the sender stride to calculate the length
1135 * in case the number of channels differ between the implicitly
1136 * fed-back endpoint and the synchronizing endpoint.
1137 */
1138
1139 out_packet->packets = in_ctx->packets;
1140 for (i = 0; i < in_ctx->packets; i++) {
1141 if (urb->iso_frame_desc[i].status == 0)
1142 out_packet->packet_size[i] =
1143 urb->iso_frame_desc[i].actual_length / sender->stride;
1144 else
1145 out_packet->packet_size[i] = 0;
1146 }
1147
1148 ep->next_packet_write_pos++;
1149 ep->next_packet_write_pos %= MAX_URBS;
1150 spin_unlock_irqrestore(&ep->lock, flags);
1151 queue_pending_output_urbs(ep);
1152
1153 return;
1154 }
1155
1156 /*
1157 * process after playback sync complete
1158 *
1159 * Full speed devices report feedback values in 10.14 format as samples
1160 * per frame, high speed devices in 16.16 format as samples per
1161 * microframe.
1162 *
1163 * Because the Audio Class 1 spec was written before USB 2.0, many high
1164 * speed devices use a wrong interpretation, some others use an
1165 * entirely different format.
1166 *
1167 * Therefore, we cannot predict what format any particular device uses
1168 * and must detect it automatically.
1169 */
1170
1171 if (urb->iso_frame_desc[0].status != 0 ||
1172 urb->iso_frame_desc[0].actual_length < 3)
1173 return;
1174
1175 f = le32_to_cpup(urb->transfer_buffer);
1176 if (urb->iso_frame_desc[0].actual_length == 3)
1177 f &= 0x00ffffff;
1178 else
1179 f &= 0x0fffffff;
1180
1181 if (f == 0)
1182 return;
1183
1184 if (unlikely(sender->tenor_fb_quirk)) {
1185 /*
1186 * Devices based on Tenor 8802 chipsets (TEAC UD-H01
1187 * and others) sometimes change the feedback value
1188 * by +/- 0x1.0000.
1189 */
1190 if (f < ep->freqn - 0x8000)
1191 f += 0xf000;
1192 else if (f > ep->freqn + 0x8000)
1193 f -= 0xf000;
1194 } else if (unlikely(ep->freqshift == INT_MIN)) {
1195 /*
1196 * The first time we see a feedback value, determine its format
1197 * by shifting it left or right until it matches the nominal
1198 * frequency value. This assumes that the feedback does not
1199 * differ from the nominal value more than +50% or -25%.
1200 */
1201 shift = 0;
1202 while (f < ep->freqn - ep->freqn / 4) {
1203 f <<= 1;
1204 shift++;
1205 }
1206 while (f > ep->freqn + ep->freqn / 2) {
1207 f >>= 1;
1208 shift--;
1209 }
1210 ep->freqshift = shift;
1211 } else if (ep->freqshift >= 0)
1212 f <<= ep->freqshift;
1213 else
1214 f >>= -ep->freqshift;
1215
1216 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1217 /*
1218 * If the frequency looks valid, set it.
1219 * This value is referred to in prepare_playback_urb().
1220 */
1221 spin_lock_irqsave(&ep->lock, flags);
1222 ep->freqm = f;
1223 spin_unlock_irqrestore(&ep->lock, flags);
1224 } else {
1225 /*
1226 * Out of range; maybe the shift value is wrong.
1227 * Reset it so that we autodetect again the next time.
1228 */
1229 ep->freqshift = INT_MIN;
1230 }
1231}
1232