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 */
get_usb_full_speed_rate(unsigned int rate)70 static 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 */
get_usb_high_speed_rate(unsigned int rate)79 static 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 */
release_urb_ctx(struct snd_urb_ctx * u)87 static 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
usb_error_string(int err)97 static 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 */
snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint * ep)130 int 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 */
snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint * ep)145 int 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
retire_outbound_urb(struct snd_usb_endpoint * ep,struct snd_urb_ctx * urb_ctx)162 static 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
retire_inbound_urb(struct snd_usb_endpoint * ep,struct snd_urb_ctx * urb_ctx)169 static 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
prepare_silent_urb(struct snd_usb_endpoint * ep,struct snd_urb_ctx * ctx)186 static 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 */
prepare_outbound_urb(struct snd_usb_endpoint * ep,struct snd_urb_ctx * ctx)230 static 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 */
prepare_inbound_urb(struct snd_usb_endpoint * ep,struct snd_urb_ctx * urb_ctx)279 static 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 */
queue_pending_output_urbs(struct snd_usb_endpoint * ep)321 static 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 */
snd_complete_urb(struct urb * urb)370 static 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
425 exit_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 */
snd_usb_add_endpoint(struct snd_usb_audio * chip,struct usb_host_interface * alts,int ep_num,int direction,int type)448 struct 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 */
wait_clear_urbs(struct snd_usb_endpoint * ep)521 static 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 */
snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint * ep)551 void 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 */
deactivate_urbs(struct snd_usb_endpoint * ep,bool force)560 static 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 */
release_urbs(struct snd_usb_endpoint * ep,int force)588 static 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 */
data_ep_set_params(struct snd_usb_endpoint * ep,snd_pcm_format_t pcm_format,unsigned int channels,unsigned int period_bytes,unsigned int frames_per_period,unsigned int periods_per_buffer,struct audioformat * fmt,struct snd_usb_endpoint * sync_ep)614 static 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 ep->silence_value = pcm_format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0;
642
643 /* assume max. frequency is 25% higher than nominal */
644 ep->freqmax = ep->freqn + (ep->freqn >> 2);
645 /* Round up freqmax to nearest integer in order to calculate maximum
646 * packet size, which must represent a whole number of frames.
647 * This is accomplished by adding 0x0.ffff before converting the
648 * Q16.16 format into integer.
649 * In order to accurately calculate the maximum packet size when
650 * the data interval is more than 1 (i.e. ep->datainterval > 0),
651 * multiply by the data interval prior to rounding. For instance,
652 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
653 * frames with a data interval of 1, but 11 (10.25) frames with a
654 * data interval of 2.
655 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
656 * maximum datainterval value of 3, at USB full speed, higher for
657 * USB high speed, noting that ep->freqmax is in units of
658 * frames per packet in Q16.16 format.)
659 */
660 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
661 (frame_bits >> 3);
662 if (tx_length_quirk)
663 maxsize += sizeof(__le32); /* Space for length descriptor */
664 /* but wMaxPacketSize might reduce this */
665 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
666 /* whatever fits into a max. size packet */
667 unsigned int data_maxsize = maxsize = ep->maxpacksize;
668
669 if (tx_length_quirk)
670 /* Need to remove the length descriptor to calc freq */
671 data_maxsize -= sizeof(__le32);
672 ep->freqmax = (data_maxsize / (frame_bits >> 3))
673 << (16 - ep->datainterval);
674 }
675
676 if (ep->fill_max)
677 ep->curpacksize = ep->maxpacksize;
678 else
679 ep->curpacksize = maxsize;
680
681 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) {
682 packs_per_ms = 8 >> ep->datainterval;
683 max_packs_per_urb = MAX_PACKS_HS;
684 } else {
685 packs_per_ms = 1;
686 max_packs_per_urb = MAX_PACKS;
687 }
688 if (sync_ep && !snd_usb_endpoint_implicit_feedback_sink(ep))
689 max_packs_per_urb = min(max_packs_per_urb,
690 1U << sync_ep->syncinterval);
691 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
692
693 /*
694 * Capture endpoints need to use small URBs because there's no way
695 * to tell in advance where the next period will end, and we don't
696 * want the next URB to complete much after the period ends.
697 *
698 * Playback endpoints with implicit sync much use the same parameters
699 * as their corresponding capture endpoint.
700 */
701 if (usb_pipein(ep->pipe) ||
702 snd_usb_endpoint_implicit_feedback_sink(ep)) {
703
704 urb_packs = packs_per_ms;
705 /*
706 * Wireless devices can poll at a max rate of once per 4ms.
707 * For dataintervals less than 5, increase the packet count to
708 * allow the host controller to use bursting to fill in the
709 * gaps.
710 */
711 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_WIRELESS) {
712 int interval = ep->datainterval;
713 while (interval < 5) {
714 urb_packs <<= 1;
715 ++interval;
716 }
717 }
718 /* make capture URBs <= 1 ms and smaller than a period */
719 urb_packs = min(max_packs_per_urb, urb_packs);
720 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
721 urb_packs >>= 1;
722 ep->nurbs = MAX_URBS;
723
724 /*
725 * Playback endpoints without implicit sync are adjusted so that
726 * a period fits as evenly as possible in the smallest number of
727 * URBs. The total number of URBs is adjusted to the size of the
728 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
729 */
730 } else {
731 /* determine how small a packet can be */
732 minsize = (ep->freqn >> (16 - ep->datainterval)) *
733 (frame_bits >> 3);
734 /* with sync from device, assume it can be 12% lower */
735 if (sync_ep)
736 minsize -= minsize >> 3;
737 minsize = max(minsize, 1u);
738
739 /* how many packets will contain an entire ALSA period? */
740 max_packs_per_period = DIV_ROUND_UP(period_bytes, minsize);
741
742 /* how many URBs will contain a period? */
743 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
744 max_packs_per_urb);
745 /* how many packets are needed in each URB? */
746 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
747
748 /* limit the number of frames in a single URB */
749 ep->max_urb_frames = DIV_ROUND_UP(frames_per_period,
750 urbs_per_period);
751
752 /* try to use enough URBs to contain an entire ALSA buffer */
753 max_urbs = min((unsigned) MAX_URBS,
754 MAX_QUEUE * packs_per_ms / urb_packs);
755 ep->nurbs = min(max_urbs, urbs_per_period * periods_per_buffer);
756 }
757
758 /* allocate and initialize data urbs */
759 for (i = 0; i < ep->nurbs; i++) {
760 struct snd_urb_ctx *u = &ep->urb[i];
761 u->index = i;
762 u->ep = ep;
763 u->packets = urb_packs;
764 u->buffer_size = maxsize * u->packets;
765
766 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
767 u->packets++; /* for transfer delimiter */
768 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
769 if (!u->urb)
770 goto out_of_memory;
771
772 u->urb->transfer_buffer =
773 usb_alloc_coherent(ep->chip->dev, u->buffer_size,
774 GFP_KERNEL, &u->urb->transfer_dma);
775 if (!u->urb->transfer_buffer)
776 goto out_of_memory;
777 u->urb->pipe = ep->pipe;
778 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
779 u->urb->interval = 1 << ep->datainterval;
780 u->urb->context = u;
781 u->urb->complete = snd_complete_urb;
782 INIT_LIST_HEAD(&u->ready_list);
783 }
784
785 return 0;
786
787 out_of_memory:
788 release_urbs(ep, 0);
789 return -ENOMEM;
790 }
791
792 /*
793 * configure a sync endpoint
794 */
sync_ep_set_params(struct snd_usb_endpoint * ep)795 static int sync_ep_set_params(struct snd_usb_endpoint *ep)
796 {
797 int i;
798
799 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4,
800 GFP_KERNEL, &ep->sync_dma);
801 if (!ep->syncbuf)
802 return -ENOMEM;
803
804 for (i = 0; i < SYNC_URBS; i++) {
805 struct snd_urb_ctx *u = &ep->urb[i];
806 u->index = i;
807 u->ep = ep;
808 u->packets = 1;
809 u->urb = usb_alloc_urb(1, GFP_KERNEL);
810 if (!u->urb)
811 goto out_of_memory;
812 u->urb->transfer_buffer = ep->syncbuf + i * 4;
813 u->urb->transfer_dma = ep->sync_dma + i * 4;
814 u->urb->transfer_buffer_length = 4;
815 u->urb->pipe = ep->pipe;
816 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
817 u->urb->number_of_packets = 1;
818 u->urb->interval = 1 << ep->syncinterval;
819 u->urb->context = u;
820 u->urb->complete = snd_complete_urb;
821 }
822
823 ep->nurbs = SYNC_URBS;
824
825 return 0;
826
827 out_of_memory:
828 release_urbs(ep, 0);
829 return -ENOMEM;
830 }
831
832 /**
833 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
834 *
835 * @ep: the snd_usb_endpoint to configure
836 * @pcm_format: the audio fomat.
837 * @channels: the number of audio channels.
838 * @period_bytes: the number of bytes in one alsa period.
839 * @period_frames: the number of frames in one alsa period.
840 * @buffer_periods: the number of periods in one alsa buffer.
841 * @rate: the frame rate.
842 * @fmt: the USB audio format information
843 * @sync_ep: the sync endpoint to use, if any
844 *
845 * Determine the number of URBs to be used on this endpoint.
846 * An endpoint must be configured before it can be started.
847 * An endpoint that is already running can not be reconfigured.
848 */
snd_usb_endpoint_set_params(struct snd_usb_endpoint * ep,snd_pcm_format_t pcm_format,unsigned int channels,unsigned int period_bytes,unsigned int period_frames,unsigned int buffer_periods,unsigned int rate,struct audioformat * fmt,struct snd_usb_endpoint * sync_ep)849 int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
850 snd_pcm_format_t pcm_format,
851 unsigned int channels,
852 unsigned int period_bytes,
853 unsigned int period_frames,
854 unsigned int buffer_periods,
855 unsigned int rate,
856 struct audioformat *fmt,
857 struct snd_usb_endpoint *sync_ep)
858 {
859 int err;
860
861 if (ep->use_count != 0) {
862 usb_audio_warn(ep->chip,
863 "Unable to change format on ep #%x: already in use\n",
864 ep->ep_num);
865 return -EBUSY;
866 }
867
868 /* release old buffers, if any */
869 release_urbs(ep, 0);
870
871 ep->datainterval = fmt->datainterval;
872 ep->maxpacksize = fmt->maxpacksize;
873 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
874
875 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL)
876 ep->freqn = get_usb_full_speed_rate(rate);
877 else
878 ep->freqn = get_usb_high_speed_rate(rate);
879
880 /* calculate the frequency in 16.16 format */
881 ep->freqm = ep->freqn;
882 ep->freqshift = INT_MIN;
883
884 ep->phase = 0;
885
886 switch (ep->type) {
887 case SND_USB_ENDPOINT_TYPE_DATA:
888 err = data_ep_set_params(ep, pcm_format, channels,
889 period_bytes, period_frames,
890 buffer_periods, fmt, sync_ep);
891 break;
892 case SND_USB_ENDPOINT_TYPE_SYNC:
893 err = sync_ep_set_params(ep);
894 break;
895 default:
896 err = -EINVAL;
897 }
898
899 usb_audio_dbg(ep->chip,
900 "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
901 ep->ep_num, ep->type, ep->nurbs, err);
902
903 return err;
904 }
905
906 /**
907 * snd_usb_endpoint_start: start an snd_usb_endpoint
908 *
909 * @ep: the endpoint to start
910 *
911 * A call to this function will increment the use count of the endpoint.
912 * In case it is not already running, the URBs for this endpoint will be
913 * submitted. Otherwise, this function does nothing.
914 *
915 * Must be balanced to calls of snd_usb_endpoint_stop().
916 *
917 * Returns an error if the URB submission failed, 0 in all other cases.
918 */
snd_usb_endpoint_start(struct snd_usb_endpoint * ep)919 int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
920 {
921 int err;
922 unsigned int i;
923
924 if (atomic_read(&ep->chip->shutdown))
925 return -EBADFD;
926
927 /* already running? */
928 if (++ep->use_count != 1)
929 return 0;
930
931 /* just to be sure */
932 deactivate_urbs(ep, false);
933
934 ep->active_mask = 0;
935 ep->unlink_mask = 0;
936 ep->phase = 0;
937
938 snd_usb_endpoint_start_quirk(ep);
939
940 /*
941 * If this endpoint has a data endpoint as implicit feedback source,
942 * don't start the urbs here. Instead, mark them all as available,
943 * wait for the record urbs to return and queue the playback urbs
944 * from that context.
945 */
946
947 set_bit(EP_FLAG_RUNNING, &ep->flags);
948
949 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
950 for (i = 0; i < ep->nurbs; i++) {
951 struct snd_urb_ctx *ctx = ep->urb + i;
952 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
953 }
954
955 return 0;
956 }
957
958 for (i = 0; i < ep->nurbs; i++) {
959 struct urb *urb = ep->urb[i].urb;
960
961 if (snd_BUG_ON(!urb))
962 goto __error;
963
964 if (usb_pipeout(ep->pipe)) {
965 prepare_outbound_urb(ep, urb->context);
966 } else {
967 prepare_inbound_urb(ep, urb->context);
968 }
969
970 err = usb_submit_urb(urb, GFP_ATOMIC);
971 if (err < 0) {
972 usb_audio_err(ep->chip,
973 "cannot submit urb %d, error %d: %s\n",
974 i, err, usb_error_string(err));
975 goto __error;
976 }
977 set_bit(i, &ep->active_mask);
978 }
979
980 return 0;
981
982 __error:
983 clear_bit(EP_FLAG_RUNNING, &ep->flags);
984 ep->use_count--;
985 deactivate_urbs(ep, false);
986 return -EPIPE;
987 }
988
989 /**
990 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
991 *
992 * @ep: the endpoint to stop (may be NULL)
993 *
994 * A call to this function will decrement the use count of the endpoint.
995 * In case the last user has requested the endpoint stop, the URBs will
996 * actually be deactivated.
997 *
998 * Must be balanced to calls of snd_usb_endpoint_start().
999 *
1000 * The caller needs to synchronize the pending stop operation via
1001 * snd_usb_endpoint_sync_pending_stop().
1002 */
snd_usb_endpoint_stop(struct snd_usb_endpoint * ep)1003 void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep)
1004 {
1005 if (!ep)
1006 return;
1007
1008 if (snd_BUG_ON(ep->use_count == 0))
1009 return;
1010
1011 if (--ep->use_count == 0) {
1012 deactivate_urbs(ep, false);
1013 set_bit(EP_FLAG_STOPPING, &ep->flags);
1014 }
1015 }
1016
1017 /**
1018 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
1019 *
1020 * @ep: the endpoint to deactivate
1021 *
1022 * If the endpoint is not currently in use, this functions will
1023 * deactivate its associated URBs.
1024 *
1025 * In case of any active users, this functions does nothing.
1026 */
snd_usb_endpoint_deactivate(struct snd_usb_endpoint * ep)1027 void snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep)
1028 {
1029 if (!ep)
1030 return;
1031
1032 if (ep->use_count != 0)
1033 return;
1034
1035 deactivate_urbs(ep, true);
1036 wait_clear_urbs(ep);
1037 }
1038
1039 /**
1040 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1041 *
1042 * @ep: the endpoint to release
1043 *
1044 * This function does not care for the endpoint's use count but will tear
1045 * down all the streaming URBs immediately.
1046 */
snd_usb_endpoint_release(struct snd_usb_endpoint * ep)1047 void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1048 {
1049 release_urbs(ep, 1);
1050 }
1051
1052 /**
1053 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
1054 *
1055 * @ep: the endpoint to free
1056 *
1057 * This free all resources of the given ep.
1058 */
snd_usb_endpoint_free(struct snd_usb_endpoint * ep)1059 void snd_usb_endpoint_free(struct snd_usb_endpoint *ep)
1060 {
1061 kfree(ep);
1062 }
1063
1064 /**
1065 * snd_usb_handle_sync_urb: parse an USB sync packet
1066 *
1067 * @ep: the endpoint to handle the packet
1068 * @sender: the sending endpoint
1069 * @urb: the received packet
1070 *
1071 * This function is called from the context of an endpoint that received
1072 * the packet and is used to let another endpoint object handle the payload.
1073 */
snd_usb_handle_sync_urb(struct snd_usb_endpoint * ep,struct snd_usb_endpoint * sender,const struct urb * urb)1074 void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1075 struct snd_usb_endpoint *sender,
1076 const struct urb *urb)
1077 {
1078 int shift;
1079 unsigned int f;
1080 unsigned long flags;
1081
1082 snd_BUG_ON(ep == sender);
1083
1084 /*
1085 * In case the endpoint is operating in implicit feedback mode, prepare
1086 * a new outbound URB that has the same layout as the received packet
1087 * and add it to the list of pending urbs. queue_pending_output_urbs()
1088 * will take care of them later.
1089 */
1090 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1091 ep->use_count != 0) {
1092
1093 /* implicit feedback case */
1094 int i, bytes = 0;
1095 struct snd_urb_ctx *in_ctx;
1096 struct snd_usb_packet_info *out_packet;
1097
1098 in_ctx = urb->context;
1099
1100 /* Count overall packet size */
1101 for (i = 0; i < in_ctx->packets; i++)
1102 if (urb->iso_frame_desc[i].status == 0)
1103 bytes += urb->iso_frame_desc[i].actual_length;
1104
1105 /*
1106 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1107 * streaming once it received a 0-byte OUT URB
1108 */
1109 if (bytes == 0)
1110 return;
1111
1112 spin_lock_irqsave(&ep->lock, flags);
1113 out_packet = ep->next_packet + ep->next_packet_write_pos;
1114
1115 /*
1116 * Iterate through the inbound packet and prepare the lengths
1117 * for the output packet. The OUT packet we are about to send
1118 * will have the same amount of payload bytes per stride as the
1119 * IN packet we just received. Since the actual size is scaled
1120 * by the stride, use the sender stride to calculate the length
1121 * in case the number of channels differ between the implicitly
1122 * fed-back endpoint and the synchronizing endpoint.
1123 */
1124
1125 out_packet->packets = in_ctx->packets;
1126 for (i = 0; i < in_ctx->packets; i++) {
1127 if (urb->iso_frame_desc[i].status == 0)
1128 out_packet->packet_size[i] =
1129 urb->iso_frame_desc[i].actual_length / sender->stride;
1130 else
1131 out_packet->packet_size[i] = 0;
1132 }
1133
1134 ep->next_packet_write_pos++;
1135 ep->next_packet_write_pos %= MAX_URBS;
1136 spin_unlock_irqrestore(&ep->lock, flags);
1137 queue_pending_output_urbs(ep);
1138
1139 return;
1140 }
1141
1142 /*
1143 * process after playback sync complete
1144 *
1145 * Full speed devices report feedback values in 10.14 format as samples
1146 * per frame, high speed devices in 16.16 format as samples per
1147 * microframe.
1148 *
1149 * Because the Audio Class 1 spec was written before USB 2.0, many high
1150 * speed devices use a wrong interpretation, some others use an
1151 * entirely different format.
1152 *
1153 * Therefore, we cannot predict what format any particular device uses
1154 * and must detect it automatically.
1155 */
1156
1157 if (urb->iso_frame_desc[0].status != 0 ||
1158 urb->iso_frame_desc[0].actual_length < 3)
1159 return;
1160
1161 f = le32_to_cpup(urb->transfer_buffer);
1162 if (urb->iso_frame_desc[0].actual_length == 3)
1163 f &= 0x00ffffff;
1164 else
1165 f &= 0x0fffffff;
1166
1167 if (f == 0)
1168 return;
1169
1170 if (unlikely(sender->tenor_fb_quirk)) {
1171 /*
1172 * Devices based on Tenor 8802 chipsets (TEAC UD-H01
1173 * and others) sometimes change the feedback value
1174 * by +/- 0x1.0000.
1175 */
1176 if (f < ep->freqn - 0x8000)
1177 f += 0xf000;
1178 else if (f > ep->freqn + 0x8000)
1179 f -= 0xf000;
1180 } else if (unlikely(ep->freqshift == INT_MIN)) {
1181 /*
1182 * The first time we see a feedback value, determine its format
1183 * by shifting it left or right until it matches the nominal
1184 * frequency value. This assumes that the feedback does not
1185 * differ from the nominal value more than +50% or -25%.
1186 */
1187 shift = 0;
1188 while (f < ep->freqn - ep->freqn / 4) {
1189 f <<= 1;
1190 shift++;
1191 }
1192 while (f > ep->freqn + ep->freqn / 2) {
1193 f >>= 1;
1194 shift--;
1195 }
1196 ep->freqshift = shift;
1197 } else if (ep->freqshift >= 0)
1198 f <<= ep->freqshift;
1199 else
1200 f >>= -ep->freqshift;
1201
1202 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1203 /*
1204 * If the frequency looks valid, set it.
1205 * This value is referred to in prepare_playback_urb().
1206 */
1207 spin_lock_irqsave(&ep->lock, flags);
1208 ep->freqm = f;
1209 spin_unlock_irqrestore(&ep->lock, flags);
1210 } else {
1211 /*
1212 * Out of range; maybe the shift value is wrong.
1213 * Reset it so that we autodetect again the next time.
1214 */
1215 ep->freqshift = INT_MIN;
1216 }
1217 }
1218
1219