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
186 /*
187 * Prepare a PLAYBACK urb for submission to the bus.
188 */
prepare_outbound_urb(struct snd_usb_endpoint * ep,struct snd_urb_ctx * ctx)189 static 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 */
prepare_inbound_urb(struct snd_usb_endpoint * ep,struct snd_urb_ctx * urb_ctx)256 static 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 */
queue_pending_output_urbs(struct snd_usb_endpoint * ep)298 static 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 */
snd_complete_urb(struct urb * urb)347 static 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 struct snd_pcm_substream *substream;
352 unsigned long flags;
353 int err;
354
355 if (unlikely(urb->status == -ENOENT || /* unlinked */
356 urb->status == -ENODEV || /* device removed */
357 urb->status == -ECONNRESET || /* unlinked */
358 urb->status == -ESHUTDOWN)) /* device disabled */
359 goto exit_clear;
360 /* device disconnected */
361 if (unlikely(atomic_read(&ep->chip->shutdown)))
362 goto exit_clear;
363
364 if (usb_pipeout(ep->pipe)) {
365 retire_outbound_urb(ep, ctx);
366 /* can be stopped during retire callback */
367 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
368 goto exit_clear;
369
370 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
371 spin_lock_irqsave(&ep->lock, flags);
372 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
373 spin_unlock_irqrestore(&ep->lock, flags);
374 queue_pending_output_urbs(ep);
375
376 goto exit_clear;
377 }
378
379 prepare_outbound_urb(ep, ctx);
380 } else {
381 retire_inbound_urb(ep, ctx);
382 /* can be stopped during retire callback */
383 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
384 goto exit_clear;
385
386 prepare_inbound_urb(ep, ctx);
387 }
388
389 err = usb_submit_urb(urb, GFP_ATOMIC);
390 if (err == 0)
391 return;
392
393 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
394 if (ep->data_subs && ep->data_subs->pcm_substream) {
395 substream = ep->data_subs->pcm_substream;
396 snd_pcm_stop_xrun(substream);
397 }
398
399 exit_clear:
400 clear_bit(ctx->index, &ep->active_mask);
401 }
402
403 /**
404 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
405 *
406 * @chip: The chip
407 * @alts: The USB host interface
408 * @ep_num: The number of the endpoint to use
409 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
410 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
411 *
412 * If the requested endpoint has not been added to the given chip before,
413 * a new instance is created. Otherwise, a pointer to the previoulsy
414 * created instance is returned. In case of any error, NULL is returned.
415 *
416 * New endpoints will be added to chip->ep_list and must be freed by
417 * calling snd_usb_endpoint_free().
418 *
419 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
420 * bNumEndpoints > 1 beforehand.
421 */
snd_usb_add_endpoint(struct snd_usb_audio * chip,struct usb_host_interface * alts,int ep_num,int direction,int type)422 struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
423 struct usb_host_interface *alts,
424 int ep_num, int direction, int type)
425 {
426 struct snd_usb_endpoint *ep;
427 int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK;
428
429 if (WARN_ON(!alts))
430 return NULL;
431
432 mutex_lock(&chip->mutex);
433
434 list_for_each_entry(ep, &chip->ep_list, list) {
435 if (ep->ep_num == ep_num &&
436 ep->iface == alts->desc.bInterfaceNumber &&
437 ep->altsetting == alts->desc.bAlternateSetting) {
438 usb_audio_dbg(ep->chip,
439 "Re-using EP %x in iface %d,%d @%p\n",
440 ep_num, ep->iface, ep->altsetting, ep);
441 goto __exit_unlock;
442 }
443 }
444
445 usb_audio_dbg(chip, "Creating new %s %s endpoint #%x\n",
446 is_playback ? "playback" : "capture",
447 type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync",
448 ep_num);
449
450 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
451 if (!ep)
452 goto __exit_unlock;
453
454 ep->chip = chip;
455 spin_lock_init(&ep->lock);
456 ep->type = type;
457 ep->ep_num = ep_num;
458 ep->iface = alts->desc.bInterfaceNumber;
459 ep->altsetting = alts->desc.bAlternateSetting;
460 INIT_LIST_HEAD(&ep->ready_playback_urbs);
461 ep_num &= USB_ENDPOINT_NUMBER_MASK;
462
463 if (is_playback)
464 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
465 else
466 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
467
468 if (type == SND_USB_ENDPOINT_TYPE_SYNC) {
469 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
470 get_endpoint(alts, 1)->bRefresh >= 1 &&
471 get_endpoint(alts, 1)->bRefresh <= 9)
472 ep->syncinterval = get_endpoint(alts, 1)->bRefresh;
473 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
474 ep->syncinterval = 1;
475 else if (get_endpoint(alts, 1)->bInterval >= 1 &&
476 get_endpoint(alts, 1)->bInterval <= 16)
477 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1;
478 else
479 ep->syncinterval = 3;
480
481 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize);
482
483 if (chip->usb_id == USB_ID(0x0644, 0x8038) /* TEAC UD-H01 */ &&
484 ep->syncmaxsize == 4)
485 ep->udh01_fb_quirk = 1;
486 }
487
488 list_add_tail(&ep->list, &chip->ep_list);
489
490 __exit_unlock:
491 mutex_unlock(&chip->mutex);
492
493 return ep;
494 }
495
496 /*
497 * wait until all urbs are processed.
498 */
wait_clear_urbs(struct snd_usb_endpoint * ep)499 static int wait_clear_urbs(struct snd_usb_endpoint *ep)
500 {
501 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
502 int alive;
503
504 do {
505 alive = bitmap_weight(&ep->active_mask, ep->nurbs);
506 if (!alive)
507 break;
508
509 schedule_timeout_uninterruptible(1);
510 } while (time_before(jiffies, end_time));
511
512 if (alive)
513 usb_audio_err(ep->chip,
514 "timeout: still %d active urbs on EP #%x\n",
515 alive, ep->ep_num);
516 clear_bit(EP_FLAG_STOPPING, &ep->flags);
517
518 return 0;
519 }
520
521 /* sync the pending stop operation;
522 * this function itself doesn't trigger the stop operation
523 */
snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint * ep)524 void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
525 {
526 if (ep && test_bit(EP_FLAG_STOPPING, &ep->flags))
527 wait_clear_urbs(ep);
528 }
529
530 /*
531 * unlink active urbs.
532 */
deactivate_urbs(struct snd_usb_endpoint * ep,bool force)533 static int deactivate_urbs(struct snd_usb_endpoint *ep, bool force)
534 {
535 unsigned int i;
536
537 if (!force && atomic_read(&ep->chip->shutdown)) /* to be sure... */
538 return -EBADFD;
539
540 clear_bit(EP_FLAG_RUNNING, &ep->flags);
541
542 INIT_LIST_HEAD(&ep->ready_playback_urbs);
543 ep->next_packet_read_pos = 0;
544 ep->next_packet_write_pos = 0;
545
546 for (i = 0; i < ep->nurbs; i++) {
547 if (test_bit(i, &ep->active_mask)) {
548 if (!test_and_set_bit(i, &ep->unlink_mask)) {
549 struct urb *u = ep->urb[i].urb;
550 usb_unlink_urb(u);
551 }
552 }
553 }
554
555 return 0;
556 }
557
558 /*
559 * release an endpoint's urbs
560 */
release_urbs(struct snd_usb_endpoint * ep,int force)561 static void release_urbs(struct snd_usb_endpoint *ep, int force)
562 {
563 int i;
564
565 /* route incoming urbs to nirvana */
566 ep->retire_data_urb = NULL;
567 ep->prepare_data_urb = NULL;
568
569 /* stop urbs */
570 deactivate_urbs(ep, force);
571 wait_clear_urbs(ep);
572
573 for (i = 0; i < ep->nurbs; i++)
574 release_urb_ctx(&ep->urb[i]);
575
576 if (ep->syncbuf)
577 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
578 ep->syncbuf, ep->sync_dma);
579
580 ep->syncbuf = NULL;
581 ep->nurbs = 0;
582 }
583
584 /*
585 * configure a data endpoint
586 */
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)587 static int data_ep_set_params(struct snd_usb_endpoint *ep,
588 snd_pcm_format_t pcm_format,
589 unsigned int channels,
590 unsigned int period_bytes,
591 unsigned int frames_per_period,
592 unsigned int periods_per_buffer,
593 struct audioformat *fmt,
594 struct snd_usb_endpoint *sync_ep)
595 {
596 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
597 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
598 unsigned int max_urbs, i;
599 int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels;
600
601 if (pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
602 /*
603 * When operating in DSD DOP mode, the size of a sample frame
604 * in hardware differs from the actual physical format width
605 * because we need to make room for the DOP markers.
606 */
607 frame_bits += channels << 3;
608 }
609
610 ep->datainterval = fmt->datainterval;
611 ep->stride = frame_bits >> 3;
612 ep->silence_value = pcm_format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0;
613
614 /* assume max. frequency is 25% higher than nominal */
615 ep->freqmax = ep->freqn + (ep->freqn >> 2);
616 maxsize = ((ep->freqmax + 0xffff) * (frame_bits >> 3))
617 >> (16 - ep->datainterval);
618 /* but wMaxPacketSize might reduce this */
619 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
620 /* whatever fits into a max. size packet */
621 maxsize = ep->maxpacksize;
622 ep->freqmax = (maxsize / (frame_bits >> 3))
623 << (16 - ep->datainterval);
624 }
625
626 if (ep->fill_max)
627 ep->curpacksize = ep->maxpacksize;
628 else
629 ep->curpacksize = maxsize;
630
631 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) {
632 packs_per_ms = 8 >> ep->datainterval;
633 max_packs_per_urb = MAX_PACKS_HS;
634 } else {
635 packs_per_ms = 1;
636 max_packs_per_urb = MAX_PACKS;
637 }
638 if (sync_ep && !snd_usb_endpoint_implicit_feedback_sink(ep))
639 max_packs_per_urb = min(max_packs_per_urb,
640 1U << sync_ep->syncinterval);
641 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
642
643 /*
644 * Capture endpoints need to use small URBs because there's no way
645 * to tell in advance where the next period will end, and we don't
646 * want the next URB to complete much after the period ends.
647 *
648 * Playback endpoints with implicit sync much use the same parameters
649 * as their corresponding capture endpoint.
650 */
651 if (usb_pipein(ep->pipe) ||
652 snd_usb_endpoint_implicit_feedback_sink(ep)) {
653
654 urb_packs = packs_per_ms;
655 /*
656 * Wireless devices can poll at a max rate of once per 4ms.
657 * For dataintervals less than 5, increase the packet count to
658 * allow the host controller to use bursting to fill in the
659 * gaps.
660 */
661 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_WIRELESS) {
662 int interval = ep->datainterval;
663 while (interval < 5) {
664 urb_packs <<= 1;
665 ++interval;
666 }
667 }
668 /* make capture URBs <= 1 ms and smaller than a period */
669 urb_packs = min(max_packs_per_urb, urb_packs);
670 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
671 urb_packs >>= 1;
672 ep->nurbs = MAX_URBS;
673
674 /*
675 * Playback endpoints without implicit sync are adjusted so that
676 * a period fits as evenly as possible in the smallest number of
677 * URBs. The total number of URBs is adjusted to the size of the
678 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
679 */
680 } else {
681 /* determine how small a packet can be */
682 minsize = (ep->freqn >> (16 - ep->datainterval)) *
683 (frame_bits >> 3);
684 /* with sync from device, assume it can be 12% lower */
685 if (sync_ep)
686 minsize -= minsize >> 3;
687 minsize = max(minsize, 1u);
688
689 /* how many packets will contain an entire ALSA period? */
690 max_packs_per_period = DIV_ROUND_UP(period_bytes, minsize);
691
692 /* how many URBs will contain a period? */
693 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
694 max_packs_per_urb);
695 /* how many packets are needed in each URB? */
696 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
697
698 /* limit the number of frames in a single URB */
699 ep->max_urb_frames = DIV_ROUND_UP(frames_per_period,
700 urbs_per_period);
701
702 /* try to use enough URBs to contain an entire ALSA buffer */
703 max_urbs = min((unsigned) MAX_URBS,
704 MAX_QUEUE * packs_per_ms / urb_packs);
705 ep->nurbs = min(max_urbs, urbs_per_period * periods_per_buffer);
706 }
707
708 /* allocate and initialize data urbs */
709 for (i = 0; i < ep->nurbs; i++) {
710 struct snd_urb_ctx *u = &ep->urb[i];
711 u->index = i;
712 u->ep = ep;
713 u->packets = urb_packs;
714 u->buffer_size = maxsize * u->packets;
715
716 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
717 u->packets++; /* for transfer delimiter */
718 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
719 if (!u->urb)
720 goto out_of_memory;
721
722 u->urb->transfer_buffer =
723 usb_alloc_coherent(ep->chip->dev, u->buffer_size,
724 GFP_KERNEL, &u->urb->transfer_dma);
725 if (!u->urb->transfer_buffer)
726 goto out_of_memory;
727 u->urb->pipe = ep->pipe;
728 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
729 u->urb->interval = 1 << ep->datainterval;
730 u->urb->context = u;
731 u->urb->complete = snd_complete_urb;
732 INIT_LIST_HEAD(&u->ready_list);
733 }
734
735 return 0;
736
737 out_of_memory:
738 release_urbs(ep, 0);
739 return -ENOMEM;
740 }
741
742 /*
743 * configure a sync endpoint
744 */
sync_ep_set_params(struct snd_usb_endpoint * ep)745 static int sync_ep_set_params(struct snd_usb_endpoint *ep)
746 {
747 int i;
748
749 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4,
750 GFP_KERNEL, &ep->sync_dma);
751 if (!ep->syncbuf)
752 return -ENOMEM;
753
754 for (i = 0; i < SYNC_URBS; i++) {
755 struct snd_urb_ctx *u = &ep->urb[i];
756 u->index = i;
757 u->ep = ep;
758 u->packets = 1;
759 u->urb = usb_alloc_urb(1, GFP_KERNEL);
760 if (!u->urb)
761 goto out_of_memory;
762 u->urb->transfer_buffer = ep->syncbuf + i * 4;
763 u->urb->transfer_dma = ep->sync_dma + i * 4;
764 u->urb->transfer_buffer_length = 4;
765 u->urb->pipe = ep->pipe;
766 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
767 u->urb->number_of_packets = 1;
768 u->urb->interval = 1 << ep->syncinterval;
769 u->urb->context = u;
770 u->urb->complete = snd_complete_urb;
771 }
772
773 ep->nurbs = SYNC_URBS;
774
775 return 0;
776
777 out_of_memory:
778 release_urbs(ep, 0);
779 return -ENOMEM;
780 }
781
782 /**
783 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
784 *
785 * @ep: the snd_usb_endpoint to configure
786 * @pcm_format: the audio fomat.
787 * @channels: the number of audio channels.
788 * @period_bytes: the number of bytes in one alsa period.
789 * @period_frames: the number of frames in one alsa period.
790 * @buffer_periods: the number of periods in one alsa buffer.
791 * @rate: the frame rate.
792 * @fmt: the USB audio format information
793 * @sync_ep: the sync endpoint to use, if any
794 *
795 * Determine the number of URBs to be used on this endpoint.
796 * An endpoint must be configured before it can be started.
797 * An endpoint that is already running can not be reconfigured.
798 */
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)799 int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
800 snd_pcm_format_t pcm_format,
801 unsigned int channels,
802 unsigned int period_bytes,
803 unsigned int period_frames,
804 unsigned int buffer_periods,
805 unsigned int rate,
806 struct audioformat *fmt,
807 struct snd_usb_endpoint *sync_ep)
808 {
809 int err;
810
811 if (ep->use_count != 0) {
812 usb_audio_warn(ep->chip,
813 "Unable to change format on ep #%x: already in use\n",
814 ep->ep_num);
815 return -EBUSY;
816 }
817
818 /* release old buffers, if any */
819 release_urbs(ep, 0);
820
821 ep->datainterval = fmt->datainterval;
822 ep->maxpacksize = fmt->maxpacksize;
823 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
824
825 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL)
826 ep->freqn = get_usb_full_speed_rate(rate);
827 else
828 ep->freqn = get_usb_high_speed_rate(rate);
829
830 /* calculate the frequency in 16.16 format */
831 ep->freqm = ep->freqn;
832 ep->freqshift = INT_MIN;
833
834 ep->phase = 0;
835
836 switch (ep->type) {
837 case SND_USB_ENDPOINT_TYPE_DATA:
838 err = data_ep_set_params(ep, pcm_format, channels,
839 period_bytes, period_frames,
840 buffer_periods, fmt, sync_ep);
841 break;
842 case SND_USB_ENDPOINT_TYPE_SYNC:
843 err = sync_ep_set_params(ep);
844 break;
845 default:
846 err = -EINVAL;
847 }
848
849 usb_audio_dbg(ep->chip,
850 "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
851 ep->ep_num, ep->type, ep->nurbs, err);
852
853 return err;
854 }
855
856 /**
857 * snd_usb_endpoint_start: start an snd_usb_endpoint
858 *
859 * @ep: the endpoint to start
860 * @can_sleep: flag indicating whether the operation is executed in
861 * non-atomic context
862 *
863 * A call to this function will increment the use count of the endpoint.
864 * In case it is not already running, the URBs for this endpoint will be
865 * submitted. Otherwise, this function does nothing.
866 *
867 * Must be balanced to calls of snd_usb_endpoint_stop().
868 *
869 * Returns an error if the URB submission failed, 0 in all other cases.
870 */
snd_usb_endpoint_start(struct snd_usb_endpoint * ep,bool can_sleep)871 int snd_usb_endpoint_start(struct snd_usb_endpoint *ep, bool can_sleep)
872 {
873 int err;
874 unsigned int i;
875
876 if (atomic_read(&ep->chip->shutdown))
877 return -EBADFD;
878
879 /* already running? */
880 if (++ep->use_count != 1)
881 return 0;
882
883 /* just to be sure */
884 deactivate_urbs(ep, false);
885 if (can_sleep)
886 wait_clear_urbs(ep);
887
888 ep->active_mask = 0;
889 ep->unlink_mask = 0;
890 ep->phase = 0;
891
892 snd_usb_endpoint_start_quirk(ep);
893
894 /*
895 * If this endpoint has a data endpoint as implicit feedback source,
896 * don't start the urbs here. Instead, mark them all as available,
897 * wait for the record urbs to return and queue the playback urbs
898 * from that context.
899 */
900
901 set_bit(EP_FLAG_RUNNING, &ep->flags);
902
903 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
904 for (i = 0; i < ep->nurbs; i++) {
905 struct snd_urb_ctx *ctx = ep->urb + i;
906 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
907 }
908
909 return 0;
910 }
911
912 for (i = 0; i < ep->nurbs; i++) {
913 struct urb *urb = ep->urb[i].urb;
914
915 if (snd_BUG_ON(!urb))
916 goto __error;
917
918 if (usb_pipeout(ep->pipe)) {
919 prepare_outbound_urb(ep, urb->context);
920 } else {
921 prepare_inbound_urb(ep, urb->context);
922 }
923
924 err = usb_submit_urb(urb, GFP_ATOMIC);
925 if (err < 0) {
926 usb_audio_err(ep->chip,
927 "cannot submit urb %d, error %d: %s\n",
928 i, err, usb_error_string(err));
929 goto __error;
930 }
931 set_bit(i, &ep->active_mask);
932 }
933
934 return 0;
935
936 __error:
937 clear_bit(EP_FLAG_RUNNING, &ep->flags);
938 ep->use_count--;
939 deactivate_urbs(ep, false);
940 return -EPIPE;
941 }
942
943 /**
944 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
945 *
946 * @ep: the endpoint to stop (may be NULL)
947 *
948 * A call to this function will decrement the use count of the endpoint.
949 * In case the last user has requested the endpoint stop, the URBs will
950 * actually be deactivated.
951 *
952 * Must be balanced to calls of snd_usb_endpoint_start().
953 *
954 * The caller needs to synchronize the pending stop operation via
955 * snd_usb_endpoint_sync_pending_stop().
956 */
snd_usb_endpoint_stop(struct snd_usb_endpoint * ep)957 void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep)
958 {
959 if (!ep)
960 return;
961
962 if (snd_BUG_ON(ep->use_count == 0))
963 return;
964
965 if (--ep->use_count == 0) {
966 deactivate_urbs(ep, false);
967 ep->data_subs = NULL;
968 ep->sync_slave = NULL;
969 ep->retire_data_urb = NULL;
970 ep->prepare_data_urb = NULL;
971 set_bit(EP_FLAG_STOPPING, &ep->flags);
972 }
973 }
974
975 /**
976 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
977 *
978 * @ep: the endpoint to deactivate
979 *
980 * If the endpoint is not currently in use, this functions will
981 * deactivate its associated URBs.
982 *
983 * In case of any active users, this functions does nothing.
984 */
snd_usb_endpoint_deactivate(struct snd_usb_endpoint * ep)985 void snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep)
986 {
987 if (!ep)
988 return;
989
990 if (ep->use_count != 0)
991 return;
992
993 deactivate_urbs(ep, true);
994 wait_clear_urbs(ep);
995 }
996
997 /**
998 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
999 *
1000 * @ep: the endpoint to release
1001 *
1002 * This function does not care for the endpoint's use count but will tear
1003 * down all the streaming URBs immediately.
1004 */
snd_usb_endpoint_release(struct snd_usb_endpoint * ep)1005 void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1006 {
1007 release_urbs(ep, 1);
1008 }
1009
1010 /**
1011 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
1012 *
1013 * @ep: the endpoint to free
1014 *
1015 * This free all resources of the given ep.
1016 */
snd_usb_endpoint_free(struct snd_usb_endpoint * ep)1017 void snd_usb_endpoint_free(struct snd_usb_endpoint *ep)
1018 {
1019 kfree(ep);
1020 }
1021
1022 /**
1023 * snd_usb_handle_sync_urb: parse an USB sync packet
1024 *
1025 * @ep: the endpoint to handle the packet
1026 * @sender: the sending endpoint
1027 * @urb: the received packet
1028 *
1029 * This function is called from the context of an endpoint that received
1030 * the packet and is used to let another endpoint object handle the payload.
1031 */
snd_usb_handle_sync_urb(struct snd_usb_endpoint * ep,struct snd_usb_endpoint * sender,const struct urb * urb)1032 void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1033 struct snd_usb_endpoint *sender,
1034 const struct urb *urb)
1035 {
1036 int shift;
1037 unsigned int f;
1038 unsigned long flags;
1039
1040 snd_BUG_ON(ep == sender);
1041
1042 /*
1043 * In case the endpoint is operating in implicit feedback mode, prepare
1044 * a new outbound URB that has the same layout as the received packet
1045 * and add it to the list of pending urbs. queue_pending_output_urbs()
1046 * will take care of them later.
1047 */
1048 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1049 ep->use_count != 0) {
1050
1051 /* implicit feedback case */
1052 int i, bytes = 0;
1053 struct snd_urb_ctx *in_ctx;
1054 struct snd_usb_packet_info *out_packet;
1055
1056 in_ctx = urb->context;
1057
1058 /* Count overall packet size */
1059 for (i = 0; i < in_ctx->packets; i++)
1060 if (urb->iso_frame_desc[i].status == 0)
1061 bytes += urb->iso_frame_desc[i].actual_length;
1062
1063 /*
1064 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1065 * streaming once it received a 0-byte OUT URB
1066 */
1067 if (bytes == 0)
1068 return;
1069
1070 spin_lock_irqsave(&ep->lock, flags);
1071 out_packet = ep->next_packet + ep->next_packet_write_pos;
1072
1073 /*
1074 * Iterate through the inbound packet and prepare the lengths
1075 * for the output packet. The OUT packet we are about to send
1076 * will have the same amount of payload bytes per stride as the
1077 * IN packet we just received. Since the actual size is scaled
1078 * by the stride, use the sender stride to calculate the length
1079 * in case the number of channels differ between the implicitly
1080 * fed-back endpoint and the synchronizing endpoint.
1081 */
1082
1083 out_packet->packets = in_ctx->packets;
1084 for (i = 0; i < in_ctx->packets; i++) {
1085 if (urb->iso_frame_desc[i].status == 0)
1086 out_packet->packet_size[i] =
1087 urb->iso_frame_desc[i].actual_length / sender->stride;
1088 else
1089 out_packet->packet_size[i] = 0;
1090 }
1091
1092 ep->next_packet_write_pos++;
1093 ep->next_packet_write_pos %= MAX_URBS;
1094 spin_unlock_irqrestore(&ep->lock, flags);
1095 queue_pending_output_urbs(ep);
1096
1097 return;
1098 }
1099
1100 /*
1101 * process after playback sync complete
1102 *
1103 * Full speed devices report feedback values in 10.14 format as samples
1104 * per frame, high speed devices in 16.16 format as samples per
1105 * microframe.
1106 *
1107 * Because the Audio Class 1 spec was written before USB 2.0, many high
1108 * speed devices use a wrong interpretation, some others use an
1109 * entirely different format.
1110 *
1111 * Therefore, we cannot predict what format any particular device uses
1112 * and must detect it automatically.
1113 */
1114
1115 if (urb->iso_frame_desc[0].status != 0 ||
1116 urb->iso_frame_desc[0].actual_length < 3)
1117 return;
1118
1119 f = le32_to_cpup(urb->transfer_buffer);
1120 if (urb->iso_frame_desc[0].actual_length == 3)
1121 f &= 0x00ffffff;
1122 else
1123 f &= 0x0fffffff;
1124
1125 if (f == 0)
1126 return;
1127
1128 if (unlikely(sender->udh01_fb_quirk)) {
1129 /*
1130 * The TEAC UD-H01 firmware sometimes changes the feedback value
1131 * by +/- 0x1.0000.
1132 */
1133 if (f < ep->freqn - 0x8000)
1134 f += 0x10000;
1135 else if (f > ep->freqn + 0x8000)
1136 f -= 0x10000;
1137 } else if (unlikely(ep->freqshift == INT_MIN)) {
1138 /*
1139 * The first time we see a feedback value, determine its format
1140 * by shifting it left or right until it matches the nominal
1141 * frequency value. This assumes that the feedback does not
1142 * differ from the nominal value more than +50% or -25%.
1143 */
1144 shift = 0;
1145 while (f < ep->freqn - ep->freqn / 4) {
1146 f <<= 1;
1147 shift++;
1148 }
1149 while (f > ep->freqn + ep->freqn / 2) {
1150 f >>= 1;
1151 shift--;
1152 }
1153 ep->freqshift = shift;
1154 } else if (ep->freqshift >= 0)
1155 f <<= ep->freqshift;
1156 else
1157 f >>= -ep->freqshift;
1158
1159 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1160 /*
1161 * If the frequency looks valid, set it.
1162 * This value is referred to in prepare_playback_urb().
1163 */
1164 spin_lock_irqsave(&ep->lock, flags);
1165 ep->freqm = f;
1166 spin_unlock_irqrestore(&ep->lock, flags);
1167 } else {
1168 /*
1169 * Out of range; maybe the shift value is wrong.
1170 * Reset it so that we autodetect again the next time.
1171 */
1172 ep->freqshift = INT_MIN;
1173 }
1174 }
1175
1176