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