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