1 // SPDX-License-Identifier: GPL-2.0-or-later
6 #include <linux/init.h>
7 #include <linux/ratelimit.h>
9 #include <linux/usb/audio.h>
10 #include <linux/slab.h>
12 #include <sound/core.h>
13 #include <sound/pcm.h>
14 #include <sound/pcm_params.h>
30 /* interface refcounting */
31 struct snd_usb_iface_ref {
35 struct list_head list;
38 /* clock refcounting */
39 struct snd_usb_clock_ref {
43 struct list_head list;
47 * snd_usb_endpoint is a model that abstracts everything related to an
48 * USB endpoint and its streaming.
50 * There are functions to activate and deactivate the streaming URBs and
51 * optional callbacks to let the pcm logic handle the actual content of the
52 * packets for playback and record. Thus, the bus streaming and the audio
53 * handlers are fully decoupled.
55 * There are two different types of endpoints in audio applications.
57 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
58 * inbound and outbound traffic.
60 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
61 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
64 * Each endpoint has to be configured prior to being used by calling
65 * snd_usb_endpoint_set_params().
67 * The model incorporates a reference counting, so that multiple users
68 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
69 * only the first user will effectively start the URBs, and only the last
70 * one to stop it will tear the URBs down again.
74 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
75 * this will overflow at approx 524 kHz
77 static inline unsigned get_usb_full_speed_rate(unsigned int rate)
79 return ((rate << 13) + 62) / 125;
83 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
84 * this will overflow at approx 4 MHz
86 static inline unsigned get_usb_high_speed_rate(unsigned int rate)
88 return ((rate << 10) + 62) / 125;
94 static void release_urb_ctx(struct snd_urb_ctx *u)
97 usb_free_coherent(u->ep->chip->dev, u->buffer_size,
98 u->urb->transfer_buffer,
99 u->urb->transfer_dma);
100 usb_free_urb(u->urb);
104 static const char *usb_error_string(int err)
110 return "endpoint not enabled";
112 return "endpoint stalled";
114 return "not enough bandwidth";
116 return "device disabled";
118 return "device suspended";
123 return "internal error";
125 return "unknown error";
129 static inline bool ep_state_running(struct snd_usb_endpoint *ep)
131 return atomic_read(&ep->state) == EP_STATE_RUNNING;
134 static inline bool ep_state_update(struct snd_usb_endpoint *ep, int old, int new)
136 return atomic_cmpxchg(&ep->state, old, new) == old;
140 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
142 * @ep: The snd_usb_endpoint
144 * Determine whether an endpoint is driven by an implicit feedback
145 * data endpoint source.
147 int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
149 return ep->implicit_fb_sync && usb_pipeout(ep->pipe);
153 * Return the number of samples to be sent in the next packet
154 * for streaming based on information derived from sync endpoints
156 * This won't be used for implicit feedback which takes the packet size
157 * returned from the sync source
159 static int slave_next_packet_size(struct snd_usb_endpoint *ep,
167 return ep->maxframesize;
169 spin_lock_irqsave(&ep->lock, flags);
170 phase = (ep->phase & 0xffff) + (ep->freqm << ep->datainterval);
171 ret = min(phase >> 16, ep->maxframesize);
172 if (avail && ret >= avail)
176 spin_unlock_irqrestore(&ep->lock, flags);
182 * Return the number of samples to be sent in the next packet
183 * for adaptive and synchronous endpoints
185 static int next_packet_size(struct snd_usb_endpoint *ep, unsigned int avail)
187 unsigned int sample_accum;
191 return ep->maxframesize;
193 sample_accum = ep->sample_accum + ep->sample_rem;
194 if (sample_accum >= ep->pps) {
195 sample_accum -= ep->pps;
196 ret = ep->packsize[1];
198 ret = ep->packsize[0];
200 if (avail && ret >= avail)
203 ep->sample_accum = sample_accum;
209 * snd_usb_endpoint_next_packet_size: Return the number of samples to be sent
212 * If the size is equal or exceeds @avail, don't proceed but return -EAGAIN
213 * Exception: @avail = 0 for skipping the check.
215 int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep,
216 struct snd_urb_ctx *ctx, int idx,
221 packet = ctx->packet_size[idx];
223 if (avail && packet >= avail)
229 return slave_next_packet_size(ep, avail);
231 return next_packet_size(ep, avail);
234 static void call_retire_callback(struct snd_usb_endpoint *ep,
237 struct snd_usb_substream *data_subs;
239 data_subs = READ_ONCE(ep->data_subs);
240 if (data_subs && ep->retire_data_urb)
241 ep->retire_data_urb(data_subs, urb);
244 static void retire_outbound_urb(struct snd_usb_endpoint *ep,
245 struct snd_urb_ctx *urb_ctx)
247 call_retire_callback(ep, urb_ctx->urb);
250 static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
251 struct snd_usb_endpoint *sender,
252 const struct urb *urb);
254 static void retire_inbound_urb(struct snd_usb_endpoint *ep,
255 struct snd_urb_ctx *urb_ctx)
257 struct urb *urb = urb_ctx->urb;
258 struct snd_usb_endpoint *sync_sink;
260 if (unlikely(ep->skip_packets > 0)) {
265 sync_sink = READ_ONCE(ep->sync_sink);
267 snd_usb_handle_sync_urb(sync_sink, ep, urb);
269 call_retire_callback(ep, urb);
272 static inline bool has_tx_length_quirk(struct snd_usb_audio *chip)
274 return chip->quirk_flags & QUIRK_FLAG_TX_LENGTH;
277 static void prepare_silent_urb(struct snd_usb_endpoint *ep,
278 struct snd_urb_ctx *ctx)
280 struct urb *urb = ctx->urb;
281 unsigned int offs = 0;
282 unsigned int extra = 0;
283 __le32 packet_length;
286 /* For tx_length_quirk, put packet length at start of packet */
287 if (has_tx_length_quirk(ep->chip))
288 extra = sizeof(packet_length);
290 for (i = 0; i < ctx->packets; ++i) {
295 counts = snd_usb_endpoint_next_packet_size(ep, ctx, i, 0);
296 length = counts * ep->stride; /* number of silent bytes */
297 offset = offs * ep->stride + extra * i;
298 urb->iso_frame_desc[i].offset = offset;
299 urb->iso_frame_desc[i].length = length + extra;
301 packet_length = cpu_to_le32(length);
302 memcpy(urb->transfer_buffer + offset,
303 &packet_length, sizeof(packet_length));
305 memset(urb->transfer_buffer + offset + extra,
306 ep->silence_value, length);
310 urb->number_of_packets = ctx->packets;
311 urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
316 * Prepare a PLAYBACK urb for submission to the bus.
318 static int prepare_outbound_urb(struct snd_usb_endpoint *ep,
319 struct snd_urb_ctx *ctx,
322 struct urb *urb = ctx->urb;
323 unsigned char *cp = urb->transfer_buffer;
324 struct snd_usb_substream *data_subs;
326 urb->dev = ep->chip->dev; /* we need to set this at each time */
329 case SND_USB_ENDPOINT_TYPE_DATA:
330 data_subs = READ_ONCE(ep->data_subs);
331 if (data_subs && ep->prepare_data_urb)
332 return ep->prepare_data_urb(data_subs, urb, in_stream_lock);
333 /* no data provider, so send silence */
334 prepare_silent_urb(ep, ctx);
337 case SND_USB_ENDPOINT_TYPE_SYNC:
338 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
340 * fill the length and offset of each urb descriptor.
341 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
343 urb->iso_frame_desc[0].length = 4;
344 urb->iso_frame_desc[0].offset = 0;
346 cp[1] = ep->freqn >> 8;
347 cp[2] = ep->freqn >> 16;
348 cp[3] = ep->freqn >> 24;
351 * fill the length and offset of each urb descriptor.
352 * the fixed 10.14 frequency is passed through the pipe.
354 urb->iso_frame_desc[0].length = 3;
355 urb->iso_frame_desc[0].offset = 0;
356 cp[0] = ep->freqn >> 2;
357 cp[1] = ep->freqn >> 10;
358 cp[2] = ep->freqn >> 18;
367 * Prepare a CAPTURE or SYNC urb for submission to the bus.
369 static int prepare_inbound_urb(struct snd_usb_endpoint *ep,
370 struct snd_urb_ctx *urb_ctx)
373 struct urb *urb = urb_ctx->urb;
375 urb->dev = ep->chip->dev; /* we need to set this at each time */
378 case SND_USB_ENDPOINT_TYPE_DATA:
380 for (i = 0; i < urb_ctx->packets; i++) {
381 urb->iso_frame_desc[i].offset = offs;
382 urb->iso_frame_desc[i].length = ep->curpacksize;
383 offs += ep->curpacksize;
386 urb->transfer_buffer_length = offs;
387 urb->number_of_packets = urb_ctx->packets;
390 case SND_USB_ENDPOINT_TYPE_SYNC:
391 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
392 urb->iso_frame_desc[0].offset = 0;
398 /* notify an error as XRUN to the assigned PCM data substream */
399 static void notify_xrun(struct snd_usb_endpoint *ep)
401 struct snd_usb_substream *data_subs;
403 data_subs = READ_ONCE(ep->data_subs);
404 if (data_subs && data_subs->pcm_substream)
405 snd_pcm_stop_xrun(data_subs->pcm_substream);
408 static struct snd_usb_packet_info *
409 next_packet_fifo_enqueue(struct snd_usb_endpoint *ep)
411 struct snd_usb_packet_info *p;
413 p = ep->next_packet + (ep->next_packet_head + ep->next_packet_queued) %
414 ARRAY_SIZE(ep->next_packet);
415 ep->next_packet_queued++;
419 static struct snd_usb_packet_info *
420 next_packet_fifo_dequeue(struct snd_usb_endpoint *ep)
422 struct snd_usb_packet_info *p;
424 p = ep->next_packet + ep->next_packet_head;
425 ep->next_packet_head++;
426 ep->next_packet_head %= ARRAY_SIZE(ep->next_packet);
427 ep->next_packet_queued--;
431 static void push_back_to_ready_list(struct snd_usb_endpoint *ep,
432 struct snd_urb_ctx *ctx)
436 spin_lock_irqsave(&ep->lock, flags);
437 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
438 spin_unlock_irqrestore(&ep->lock, flags);
442 * Send output urbs that have been prepared previously. URBs are dequeued
443 * from ep->ready_playback_urbs and in case there aren't any available
444 * or there are no packets that have been prepared, this function does
447 * The reason why the functionality of sending and preparing URBs is separated
448 * is that host controllers don't guarantee the order in which they return
449 * inbound and outbound packets to their submitters.
451 * This function is used both for implicit feedback endpoints and in low-
452 * latency playback mode.
454 void snd_usb_queue_pending_output_urbs(struct snd_usb_endpoint *ep,
457 bool implicit_fb = snd_usb_endpoint_implicit_feedback_sink(ep);
459 while (ep_state_running(ep)) {
462 struct snd_usb_packet_info *packet;
463 struct snd_urb_ctx *ctx = NULL;
466 spin_lock_irqsave(&ep->lock, flags);
467 if ((!implicit_fb || ep->next_packet_queued > 0) &&
468 !list_empty(&ep->ready_playback_urbs)) {
469 /* take URB out of FIFO */
470 ctx = list_first_entry(&ep->ready_playback_urbs,
471 struct snd_urb_ctx, ready_list);
472 list_del_init(&ctx->ready_list);
474 packet = next_packet_fifo_dequeue(ep);
476 spin_unlock_irqrestore(&ep->lock, flags);
481 /* copy over the length information */
483 for (i = 0; i < packet->packets; i++)
484 ctx->packet_size[i] = packet->packet_size[i];
487 /* call the data handler to fill in playback data */
488 err = prepare_outbound_urb(ep, ctx, in_stream_lock);
489 /* can be stopped during prepare callback */
490 if (unlikely(!ep_state_running(ep)))
493 /* push back to ready list again for -EAGAIN */
495 push_back_to_ready_list(ep, ctx);
501 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
503 usb_audio_err(ep->chip,
504 "Unable to submit urb #%d: %d at %s\n",
505 ctx->index, err, __func__);
510 set_bit(ctx->index, &ep->active_mask);
511 atomic_inc(&ep->submitted_urbs);
516 * complete callback for urbs
518 static void snd_complete_urb(struct urb *urb)
520 struct snd_urb_ctx *ctx = urb->context;
521 struct snd_usb_endpoint *ep = ctx->ep;
524 if (unlikely(urb->status == -ENOENT || /* unlinked */
525 urb->status == -ENODEV || /* device removed */
526 urb->status == -ECONNRESET || /* unlinked */
527 urb->status == -ESHUTDOWN)) /* device disabled */
529 /* device disconnected */
530 if (unlikely(atomic_read(&ep->chip->shutdown)))
533 if (unlikely(!ep_state_running(ep)))
536 if (usb_pipeout(ep->pipe)) {
537 retire_outbound_urb(ep, ctx);
538 /* can be stopped during retire callback */
539 if (unlikely(!ep_state_running(ep)))
542 /* in low-latency and implicit-feedback modes, push back the
543 * URB to ready list at first, then process as much as possible
545 if (ep->lowlatency_playback ||
546 snd_usb_endpoint_implicit_feedback_sink(ep)) {
547 push_back_to_ready_list(ep, ctx);
548 clear_bit(ctx->index, &ep->active_mask);
549 snd_usb_queue_pending_output_urbs(ep, false);
550 atomic_dec(&ep->submitted_urbs); /* decrement at last */
554 /* in non-lowlatency mode, no error handling for prepare */
555 prepare_outbound_urb(ep, ctx, false);
556 /* can be stopped during prepare callback */
557 if (unlikely(!ep_state_running(ep)))
560 retire_inbound_urb(ep, ctx);
561 /* can be stopped during retire callback */
562 if (unlikely(!ep_state_running(ep)))
565 prepare_inbound_urb(ep, ctx);
568 err = usb_submit_urb(urb, GFP_ATOMIC);
572 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
576 clear_bit(ctx->index, &ep->active_mask);
577 atomic_dec(&ep->submitted_urbs);
581 * Find or create a refcount object for the given interface
583 * The objects are released altogether in snd_usb_endpoint_free_all()
585 static struct snd_usb_iface_ref *
586 iface_ref_find(struct snd_usb_audio *chip, int iface)
588 struct snd_usb_iface_ref *ip;
590 list_for_each_entry(ip, &chip->iface_ref_list, list)
591 if (ip->iface == iface)
594 ip = kzalloc(sizeof(*ip), GFP_KERNEL);
598 list_add_tail(&ip->list, &chip->iface_ref_list);
602 /* Similarly, a refcount object for clock */
603 static struct snd_usb_clock_ref *
604 clock_ref_find(struct snd_usb_audio *chip, int clock)
606 struct snd_usb_clock_ref *ref;
608 list_for_each_entry(ref, &chip->clock_ref_list, list)
609 if (ref->clock == clock)
612 ref = kzalloc(sizeof(*ref), GFP_KERNEL);
616 atomic_set(&ref->locked, 0);
617 list_add_tail(&ref->list, &chip->clock_ref_list);
622 * Get the existing endpoint object corresponding EP
623 * Returns NULL if not present.
625 struct snd_usb_endpoint *
626 snd_usb_get_endpoint(struct snd_usb_audio *chip, int ep_num)
628 struct snd_usb_endpoint *ep;
630 list_for_each_entry(ep, &chip->ep_list, list) {
631 if (ep->ep_num == ep_num)
638 #define ep_type_name(type) \
639 (type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync")
642 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
645 * @ep_num: The number of the endpoint to use
646 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
648 * If the requested endpoint has not been added to the given chip before,
649 * a new instance is created.
651 * Returns zero on success or a negative error code.
653 * New endpoints will be added to chip->ep_list and freed by
654 * calling snd_usb_endpoint_free_all().
656 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
657 * bNumEndpoints > 1 beforehand.
659 int snd_usb_add_endpoint(struct snd_usb_audio *chip, int ep_num, int type)
661 struct snd_usb_endpoint *ep;
664 ep = snd_usb_get_endpoint(chip, ep_num);
668 usb_audio_dbg(chip, "Creating new %s endpoint #%x\n",
671 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
676 spin_lock_init(&ep->lock);
679 INIT_LIST_HEAD(&ep->ready_playback_urbs);
680 atomic_set(&ep->submitted_urbs, 0);
682 is_playback = ((ep_num & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT);
683 ep_num &= USB_ENDPOINT_NUMBER_MASK;
685 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
687 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
689 list_add_tail(&ep->list, &chip->ep_list);
693 /* Set up syncinterval and maxsyncsize for a sync EP */
694 static void endpoint_set_syncinterval(struct snd_usb_audio *chip,
695 struct snd_usb_endpoint *ep)
697 struct usb_host_interface *alts;
698 struct usb_endpoint_descriptor *desc;
700 alts = snd_usb_get_host_interface(chip, ep->iface, ep->altsetting);
704 desc = get_endpoint(alts, ep->ep_idx);
705 if (desc->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
706 desc->bRefresh >= 1 && desc->bRefresh <= 9)
707 ep->syncinterval = desc->bRefresh;
708 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
709 ep->syncinterval = 1;
710 else if (desc->bInterval >= 1 && desc->bInterval <= 16)
711 ep->syncinterval = desc->bInterval - 1;
713 ep->syncinterval = 3;
715 ep->syncmaxsize = le16_to_cpu(desc->wMaxPacketSize);
718 static bool endpoint_compatible(struct snd_usb_endpoint *ep,
719 const struct audioformat *fp,
720 const struct snd_pcm_hw_params *params)
724 if (ep->cur_audiofmt != fp)
726 if (ep->cur_rate != params_rate(params) ||
727 ep->cur_format != params_format(params) ||
728 ep->cur_period_frames != params_period_size(params) ||
729 ep->cur_buffer_periods != params_periods(params))
735 * Check whether the given fp and hw params are compatible with the current
736 * setup of the target EP for implicit feedback sync
738 bool snd_usb_endpoint_compatible(struct snd_usb_audio *chip,
739 struct snd_usb_endpoint *ep,
740 const struct audioformat *fp,
741 const struct snd_pcm_hw_params *params)
745 mutex_lock(&chip->mutex);
746 ret = endpoint_compatible(ep, fp, params);
747 mutex_unlock(&chip->mutex);
752 * snd_usb_endpoint_open: Open the endpoint
754 * Called from hw_params to assign the endpoint to the substream.
755 * It's reference-counted, and only the first opener is allowed to set up
756 * arbitrary parameters. The later opener must be compatible with the
757 * former opened parameters.
758 * The endpoint needs to be closed via snd_usb_endpoint_close() later.
760 * Note that this function doesn't configure the endpoint. The substream
761 * needs to set it up later via snd_usb_endpoint_configure().
763 struct snd_usb_endpoint *
764 snd_usb_endpoint_open(struct snd_usb_audio *chip,
765 const struct audioformat *fp,
766 const struct snd_pcm_hw_params *params,
769 struct snd_usb_endpoint *ep;
770 int ep_num = is_sync_ep ? fp->sync_ep : fp->endpoint;
772 mutex_lock(&chip->mutex);
773 ep = snd_usb_get_endpoint(chip, ep_num);
775 usb_audio_err(chip, "Cannot find EP 0x%x to open\n", ep_num);
781 ep->iface = fp->sync_iface;
782 ep->altsetting = fp->sync_altsetting;
783 ep->ep_idx = fp->sync_ep_idx;
785 ep->iface = fp->iface;
786 ep->altsetting = fp->altsetting;
787 ep->ep_idx = fp->ep_idx;
789 usb_audio_dbg(chip, "Open EP 0x%x, iface=%d:%d, idx=%d\n",
790 ep_num, ep->iface, ep->altsetting, ep->ep_idx);
792 ep->iface_ref = iface_ref_find(chip, ep->iface);
793 if (!ep->iface_ref) {
798 if (fp->protocol != UAC_VERSION_1) {
799 ep->clock_ref = clock_ref_find(chip, fp->clock);
800 if (!ep->clock_ref) {
806 ep->cur_audiofmt = fp;
807 ep->cur_channels = fp->channels;
808 ep->cur_rate = params_rate(params);
809 ep->cur_format = params_format(params);
810 ep->cur_frame_bytes = snd_pcm_format_physical_width(ep->cur_format) *
811 ep->cur_channels / 8;
812 ep->cur_period_frames = params_period_size(params);
813 ep->cur_period_bytes = ep->cur_period_frames * ep->cur_frame_bytes;
814 ep->cur_buffer_periods = params_periods(params);
816 if (ep->type == SND_USB_ENDPOINT_TYPE_SYNC)
817 endpoint_set_syncinterval(chip, ep);
819 ep->implicit_fb_sync = fp->implicit_fb;
820 ep->need_setup = true;
822 usb_audio_dbg(chip, " channels=%d, rate=%d, format=%s, period_bytes=%d, periods=%d, implicit_fb=%d\n",
823 ep->cur_channels, ep->cur_rate,
824 snd_pcm_format_name(ep->cur_format),
825 ep->cur_period_bytes, ep->cur_buffer_periods,
826 ep->implicit_fb_sync);
829 if (WARN_ON(!ep->iface_ref)) {
834 if (!endpoint_compatible(ep, fp, params)) {
835 usb_audio_err(chip, "Incompatible EP setup for 0x%x\n",
841 usb_audio_dbg(chip, "Reopened EP 0x%x (count %d)\n",
845 if (!ep->iface_ref->opened++)
846 ep->iface_ref->need_setup = true;
851 mutex_unlock(&chip->mutex);
856 * snd_usb_endpoint_set_sync: Link data and sync endpoints
858 * Pass NULL to sync_ep to unlink again
860 void snd_usb_endpoint_set_sync(struct snd_usb_audio *chip,
861 struct snd_usb_endpoint *data_ep,
862 struct snd_usb_endpoint *sync_ep)
864 data_ep->sync_source = sync_ep;
868 * Set data endpoint callbacks and the assigned data stream
870 * Called at PCM trigger and cleanups.
871 * Pass NULL to deactivate each callback.
873 void snd_usb_endpoint_set_callback(struct snd_usb_endpoint *ep,
874 int (*prepare)(struct snd_usb_substream *subs,
876 bool in_stream_lock),
877 void (*retire)(struct snd_usb_substream *subs,
879 struct snd_usb_substream *data_subs)
881 ep->prepare_data_urb = prepare;
882 ep->retire_data_urb = retire;
884 ep->lowlatency_playback = data_subs->lowlatency_playback;
886 ep->lowlatency_playback = false;
887 WRITE_ONCE(ep->data_subs, data_subs);
890 static int endpoint_set_interface(struct snd_usb_audio *chip,
891 struct snd_usb_endpoint *ep,
894 int altset = set ? ep->altsetting : 0;
897 usb_audio_dbg(chip, "Setting usb interface %d:%d for EP 0x%x\n",
898 ep->iface, altset, ep->ep_num);
899 err = usb_set_interface(chip->dev, ep->iface, altset);
901 usb_audio_err(chip, "%d:%d: usb_set_interface failed (%d)\n",
902 ep->iface, altset, err);
906 if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY)
912 * snd_usb_endpoint_close: Close the endpoint
914 * Unreference the already opened endpoint via snd_usb_endpoint_open().
916 void snd_usb_endpoint_close(struct snd_usb_audio *chip,
917 struct snd_usb_endpoint *ep)
919 mutex_lock(&chip->mutex);
920 usb_audio_dbg(chip, "Closing EP 0x%x (count %d)\n",
921 ep->ep_num, ep->opened);
923 if (!--ep->iface_ref->opened)
924 endpoint_set_interface(chip, ep, false);
929 ep->cur_audiofmt = NULL;
931 ep->iface_ref = NULL;
932 ep->clock_ref = NULL;
933 usb_audio_dbg(chip, "EP 0x%x closed\n", ep->ep_num);
935 mutex_unlock(&chip->mutex);
938 /* Prepare for suspening EP, called from the main suspend handler */
939 void snd_usb_endpoint_suspend(struct snd_usb_endpoint *ep)
941 ep->need_setup = true;
943 ep->iface_ref->need_setup = true;
945 ep->clock_ref->rate = 0;
949 * wait until all urbs are processed.
951 static int wait_clear_urbs(struct snd_usb_endpoint *ep)
953 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
956 if (atomic_read(&ep->state) != EP_STATE_STOPPING)
960 alive = atomic_read(&ep->submitted_urbs);
964 schedule_timeout_uninterruptible(1);
965 } while (time_before(jiffies, end_time));
968 usb_audio_err(ep->chip,
969 "timeout: still %d active urbs on EP #%x\n",
972 if (ep_state_update(ep, EP_STATE_STOPPING, EP_STATE_STOPPED)) {
973 ep->sync_sink = NULL;
974 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
980 /* sync the pending stop operation;
981 * this function itself doesn't trigger the stop operation
983 void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
992 * This function moves the EP to STOPPING state if it's being RUNNING.
994 static int stop_urbs(struct snd_usb_endpoint *ep, bool force, bool keep_pending)
999 if (!force && atomic_read(&ep->running))
1002 if (!ep_state_update(ep, EP_STATE_RUNNING, EP_STATE_STOPPING))
1005 spin_lock_irqsave(&ep->lock, flags);
1006 INIT_LIST_HEAD(&ep->ready_playback_urbs);
1007 ep->next_packet_head = 0;
1008 ep->next_packet_queued = 0;
1009 spin_unlock_irqrestore(&ep->lock, flags);
1014 for (i = 0; i < ep->nurbs; i++) {
1015 if (test_bit(i, &ep->active_mask)) {
1016 if (!test_and_set_bit(i, &ep->unlink_mask)) {
1017 struct urb *u = ep->urb[i].urb;
1027 * release an endpoint's urbs
1029 static int release_urbs(struct snd_usb_endpoint *ep, bool force)
1033 /* route incoming urbs to nirvana */
1034 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
1036 /* stop and unlink urbs */
1037 err = stop_urbs(ep, force, false);
1041 wait_clear_urbs(ep);
1043 for (i = 0; i < ep->nurbs; i++)
1044 release_urb_ctx(&ep->urb[i]);
1046 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
1047 ep->syncbuf, ep->sync_dma);
1055 * configure a data endpoint
1057 static int data_ep_set_params(struct snd_usb_endpoint *ep)
1059 struct snd_usb_audio *chip = ep->chip;
1060 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
1061 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
1062 unsigned int max_urbs, i;
1063 const struct audioformat *fmt = ep->cur_audiofmt;
1064 int frame_bits = ep->cur_frame_bytes * 8;
1065 int tx_length_quirk = (has_tx_length_quirk(chip) &&
1066 usb_pipeout(ep->pipe));
1068 usb_audio_dbg(chip, "Setting params for data EP 0x%x, pipe 0x%x\n",
1069 ep->ep_num, ep->pipe);
1071 if (ep->cur_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
1073 * When operating in DSD DOP mode, the size of a sample frame
1074 * in hardware differs from the actual physical format width
1075 * because we need to make room for the DOP markers.
1077 frame_bits += ep->cur_channels << 3;
1080 ep->datainterval = fmt->datainterval;
1081 ep->stride = frame_bits >> 3;
1083 switch (ep->cur_format) {
1084 case SNDRV_PCM_FORMAT_U8:
1085 ep->silence_value = 0x80;
1087 case SNDRV_PCM_FORMAT_DSD_U8:
1088 case SNDRV_PCM_FORMAT_DSD_U16_LE:
1089 case SNDRV_PCM_FORMAT_DSD_U32_LE:
1090 case SNDRV_PCM_FORMAT_DSD_U16_BE:
1091 case SNDRV_PCM_FORMAT_DSD_U32_BE:
1092 ep->silence_value = 0x69;
1095 ep->silence_value = 0;
1098 /* assume max. frequency is 50% higher than nominal */
1099 ep->freqmax = ep->freqn + (ep->freqn >> 1);
1100 /* Round up freqmax to nearest integer in order to calculate maximum
1101 * packet size, which must represent a whole number of frames.
1102 * This is accomplished by adding 0x0.ffff before converting the
1103 * Q16.16 format into integer.
1104 * In order to accurately calculate the maximum packet size when
1105 * the data interval is more than 1 (i.e. ep->datainterval > 0),
1106 * multiply by the data interval prior to rounding. For instance,
1107 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
1108 * frames with a data interval of 1, but 11 (10.25) frames with a
1109 * data interval of 2.
1110 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
1111 * maximum datainterval value of 3, at USB full speed, higher for
1112 * USB high speed, noting that ep->freqmax is in units of
1113 * frames per packet in Q16.16 format.)
1115 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
1117 if (tx_length_quirk)
1118 maxsize += sizeof(__le32); /* Space for length descriptor */
1119 /* but wMaxPacketSize might reduce this */
1120 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
1121 /* whatever fits into a max. size packet */
1122 unsigned int data_maxsize = maxsize = ep->maxpacksize;
1124 if (tx_length_quirk)
1125 /* Need to remove the length descriptor to calc freq */
1126 data_maxsize -= sizeof(__le32);
1127 ep->freqmax = (data_maxsize / (frame_bits >> 3))
1128 << (16 - ep->datainterval);
1132 ep->curpacksize = ep->maxpacksize;
1134 ep->curpacksize = maxsize;
1136 if (snd_usb_get_speed(chip->dev) != USB_SPEED_FULL) {
1137 packs_per_ms = 8 >> ep->datainterval;
1138 max_packs_per_urb = MAX_PACKS_HS;
1141 max_packs_per_urb = MAX_PACKS;
1143 if (ep->sync_source && !ep->implicit_fb_sync)
1144 max_packs_per_urb = min(max_packs_per_urb,
1145 1U << ep->sync_source->syncinterval);
1146 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
1149 * Capture endpoints need to use small URBs because there's no way
1150 * to tell in advance where the next period will end, and we don't
1151 * want the next URB to complete much after the period ends.
1153 * Playback endpoints with implicit sync much use the same parameters
1154 * as their corresponding capture endpoint.
1156 if (usb_pipein(ep->pipe) || ep->implicit_fb_sync) {
1158 urb_packs = packs_per_ms;
1160 * Wireless devices can poll at a max rate of once per 4ms.
1161 * For dataintervals less than 5, increase the packet count to
1162 * allow the host controller to use bursting to fill in the
1165 if (snd_usb_get_speed(chip->dev) == USB_SPEED_WIRELESS) {
1166 int interval = ep->datainterval;
1167 while (interval < 5) {
1172 /* make capture URBs <= 1 ms and smaller than a period */
1173 urb_packs = min(max_packs_per_urb, urb_packs);
1174 while (urb_packs > 1 && urb_packs * maxsize >= ep->cur_period_bytes)
1176 ep->nurbs = MAX_URBS;
1179 * Playback endpoints without implicit sync are adjusted so that
1180 * a period fits as evenly as possible in the smallest number of
1181 * URBs. The total number of URBs is adjusted to the size of the
1182 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
1185 /* determine how small a packet can be */
1186 minsize = (ep->freqn >> (16 - ep->datainterval)) *
1188 /* with sync from device, assume it can be 12% lower */
1189 if (ep->sync_source)
1190 minsize -= minsize >> 3;
1191 minsize = max(minsize, 1u);
1193 /* how many packets will contain an entire ALSA period? */
1194 max_packs_per_period = DIV_ROUND_UP(ep->cur_period_bytes, minsize);
1196 /* how many URBs will contain a period? */
1197 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
1199 /* how many packets are needed in each URB? */
1200 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
1202 /* limit the number of frames in a single URB */
1203 ep->max_urb_frames = DIV_ROUND_UP(ep->cur_period_frames,
1206 /* try to use enough URBs to contain an entire ALSA buffer */
1207 max_urbs = min((unsigned) MAX_URBS,
1208 MAX_QUEUE * packs_per_ms / urb_packs);
1209 ep->nurbs = min(max_urbs, urbs_per_period * ep->cur_buffer_periods);
1212 /* allocate and initialize data urbs */
1213 for (i = 0; i < ep->nurbs; i++) {
1214 struct snd_urb_ctx *u = &ep->urb[i];
1217 u->packets = urb_packs;
1218 u->buffer_size = maxsize * u->packets;
1220 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
1221 u->packets++; /* for transfer delimiter */
1222 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
1226 u->urb->transfer_buffer =
1227 usb_alloc_coherent(chip->dev, u->buffer_size,
1228 GFP_KERNEL, &u->urb->transfer_dma);
1229 if (!u->urb->transfer_buffer)
1231 u->urb->pipe = ep->pipe;
1232 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1233 u->urb->interval = 1 << ep->datainterval;
1234 u->urb->context = u;
1235 u->urb->complete = snd_complete_urb;
1236 INIT_LIST_HEAD(&u->ready_list);
1242 release_urbs(ep, false);
1247 * configure a sync endpoint
1249 static int sync_ep_set_params(struct snd_usb_endpoint *ep)
1251 struct snd_usb_audio *chip = ep->chip;
1254 usb_audio_dbg(chip, "Setting params for sync EP 0x%x, pipe 0x%x\n",
1255 ep->ep_num, ep->pipe);
1257 ep->syncbuf = usb_alloc_coherent(chip->dev, SYNC_URBS * 4,
1258 GFP_KERNEL, &ep->sync_dma);
1262 for (i = 0; i < SYNC_URBS; i++) {
1263 struct snd_urb_ctx *u = &ep->urb[i];
1267 u->urb = usb_alloc_urb(1, GFP_KERNEL);
1270 u->urb->transfer_buffer = ep->syncbuf + i * 4;
1271 u->urb->transfer_dma = ep->sync_dma + i * 4;
1272 u->urb->transfer_buffer_length = 4;
1273 u->urb->pipe = ep->pipe;
1274 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1275 u->urb->number_of_packets = 1;
1276 u->urb->interval = 1 << ep->syncinterval;
1277 u->urb->context = u;
1278 u->urb->complete = snd_complete_urb;
1281 ep->nurbs = SYNC_URBS;
1286 release_urbs(ep, false);
1291 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
1293 * Determine the number of URBs to be used on this endpoint.
1294 * An endpoint must be configured before it can be started.
1295 * An endpoint that is already running can not be reconfigured.
1297 static int snd_usb_endpoint_set_params(struct snd_usb_audio *chip,
1298 struct snd_usb_endpoint *ep)
1300 const struct audioformat *fmt = ep->cur_audiofmt;
1303 /* release old buffers, if any */
1304 err = release_urbs(ep, false);
1308 ep->datainterval = fmt->datainterval;
1309 ep->maxpacksize = fmt->maxpacksize;
1310 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
1312 if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) {
1313 ep->freqn = get_usb_full_speed_rate(ep->cur_rate);
1314 ep->pps = 1000 >> ep->datainterval;
1316 ep->freqn = get_usb_high_speed_rate(ep->cur_rate);
1317 ep->pps = 8000 >> ep->datainterval;
1320 ep->sample_rem = ep->cur_rate % ep->pps;
1321 ep->packsize[0] = ep->cur_rate / ep->pps;
1322 ep->packsize[1] = (ep->cur_rate + (ep->pps - 1)) / ep->pps;
1324 /* calculate the frequency in 16.16 format */
1325 ep->freqm = ep->freqn;
1326 ep->freqshift = INT_MIN;
1331 case SND_USB_ENDPOINT_TYPE_DATA:
1332 err = data_ep_set_params(ep);
1334 case SND_USB_ENDPOINT_TYPE_SYNC:
1335 err = sync_ep_set_params(ep);
1341 usb_audio_dbg(chip, "Set up %d URBS, ret=%d\n", ep->nurbs, err);
1346 /* some unit conversions in runtime */
1347 ep->maxframesize = ep->maxpacksize / ep->cur_frame_bytes;
1348 ep->curframesize = ep->curpacksize / ep->cur_frame_bytes;
1353 static int init_sample_rate(struct snd_usb_audio *chip,
1354 struct snd_usb_endpoint *ep)
1356 struct snd_usb_clock_ref *clock = ep->clock_ref;
1360 if (atomic_read(&clock->locked))
1362 if (clock->rate == ep->cur_rate)
1364 if (clock->rate && clock->rate != ep->cur_rate) {
1365 usb_audio_dbg(chip, "Mismatched sample rate %d vs %d for EP 0x%x\n",
1366 clock->rate, ep->cur_rate, ep->ep_num);
1371 err = snd_usb_init_sample_rate(chip, ep->cur_audiofmt, ep->cur_rate);
1376 clock->rate = ep->cur_rate;
1381 * snd_usb_endpoint_configure: Configure the endpoint
1383 * This function sets up the EP to be fully usable state.
1384 * It's called either from hw_params or prepare callback.
1385 * The function checks need_setup flag, and performs nothing unless needed,
1386 * so it's safe to call this multiple times.
1388 * This returns zero if unchanged, 1 if the configuration has changed,
1389 * or a negative error code.
1391 int snd_usb_endpoint_configure(struct snd_usb_audio *chip,
1392 struct snd_usb_endpoint *ep)
1397 mutex_lock(&chip->mutex);
1398 if (WARN_ON(!ep->iface_ref))
1400 if (!ep->need_setup)
1403 /* If the interface has been already set up, just set EP parameters */
1404 if (!ep->iface_ref->need_setup) {
1405 /* sample rate setup of UAC1 is per endpoint, and we need
1406 * to update at each EP configuration
1408 if (ep->cur_audiofmt->protocol == UAC_VERSION_1) {
1409 err = init_sample_rate(chip, ep);
1413 err = snd_usb_endpoint_set_params(chip, ep);
1419 /* Need to deselect altsetting at first */
1420 endpoint_set_interface(chip, ep, false);
1422 /* Some UAC1 devices (e.g. Yamaha THR10) need the host interface
1423 * to be set up before parameter setups
1425 iface_first = ep->cur_audiofmt->protocol == UAC_VERSION_1;
1426 /* Workaround for devices that require the interface setup at first like UAC1 */
1427 if (chip->quirk_flags & QUIRK_FLAG_SET_IFACE_FIRST)
1430 err = endpoint_set_interface(chip, ep, true);
1435 err = snd_usb_init_pitch(chip, ep->cur_audiofmt);
1439 err = init_sample_rate(chip, ep);
1443 err = snd_usb_endpoint_set_params(chip, ep);
1447 err = snd_usb_select_mode_quirk(chip, ep->cur_audiofmt);
1451 /* for UAC2/3, enable the interface altset here at last */
1453 err = endpoint_set_interface(chip, ep, true);
1458 ep->iface_ref->need_setup = false;
1461 ep->need_setup = false;
1465 mutex_unlock(&chip->mutex);
1469 /* get the current rate set to the given clock by any endpoint */
1470 int snd_usb_endpoint_get_clock_rate(struct snd_usb_audio *chip, int clock)
1472 struct snd_usb_clock_ref *ref;
1477 mutex_lock(&chip->mutex);
1478 list_for_each_entry(ref, &chip->clock_ref_list, list) {
1479 if (ref->clock == clock) {
1484 mutex_unlock(&chip->mutex);
1489 * snd_usb_endpoint_start: start an snd_usb_endpoint
1491 * @ep: the endpoint to start
1493 * A call to this function will increment the running count of the endpoint.
1494 * In case it is not already running, the URBs for this endpoint will be
1495 * submitted. Otherwise, this function does nothing.
1497 * Must be balanced to calls of snd_usb_endpoint_stop().
1499 * Returns an error if the URB submission failed, 0 in all other cases.
1501 int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
1503 bool is_playback = usb_pipeout(ep->pipe);
1507 if (atomic_read(&ep->chip->shutdown))
1510 if (ep->sync_source)
1511 WRITE_ONCE(ep->sync_source->sync_sink, ep);
1513 usb_audio_dbg(ep->chip, "Starting %s EP 0x%x (running %d)\n",
1514 ep_type_name(ep->type), ep->ep_num,
1515 atomic_read(&ep->running));
1517 /* already running? */
1518 if (atomic_inc_return(&ep->running) != 1)
1522 atomic_inc(&ep->clock_ref->locked);
1524 ep->active_mask = 0;
1525 ep->unlink_mask = 0;
1527 ep->sample_accum = 0;
1529 snd_usb_endpoint_start_quirk(ep);
1532 * If this endpoint has a data endpoint as implicit feedback source,
1533 * don't start the urbs here. Instead, mark them all as available,
1534 * wait for the record urbs to return and queue the playback urbs
1535 * from that context.
1538 if (!ep_state_update(ep, EP_STATE_STOPPED, EP_STATE_RUNNING))
1541 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1542 !(ep->chip->quirk_flags & QUIRK_FLAG_PLAYBACK_FIRST)) {
1543 usb_audio_dbg(ep->chip, "No URB submission due to implicit fb sync\n");
1548 for (i = 0; i < ep->nurbs; i++) {
1549 struct urb *urb = ep->urb[i].urb;
1551 if (snd_BUG_ON(!urb))
1555 err = prepare_outbound_urb(ep, urb->context, true);
1557 err = prepare_inbound_urb(ep, urb->context);
1559 /* stop filling at applptr */
1562 usb_audio_dbg(ep->chip,
1563 "EP 0x%x: failed to prepare urb: %d\n",
1568 err = usb_submit_urb(urb, GFP_ATOMIC);
1570 usb_audio_err(ep->chip,
1571 "cannot submit urb %d, error %d: %s\n",
1572 i, err, usb_error_string(err));
1575 set_bit(i, &ep->active_mask);
1576 atomic_inc(&ep->submitted_urbs);
1580 usb_audio_dbg(ep->chip, "XRUN at starting EP 0x%x\n",
1585 usb_audio_dbg(ep->chip, "%d URBs submitted for EP 0x%x\n",
1589 /* put the remaining URBs to ready list */
1591 for (; i < ep->nurbs; i++)
1592 push_back_to_ready_list(ep, ep->urb + i);
1598 snd_usb_endpoint_stop(ep, false);
1603 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
1605 * @ep: the endpoint to stop (may be NULL)
1606 * @keep_pending: keep in-flight URBs
1608 * A call to this function will decrement the running count of the endpoint.
1609 * In case the last user has requested the endpoint stop, the URBs will
1610 * actually be deactivated.
1612 * Must be balanced to calls of snd_usb_endpoint_start().
1614 * The caller needs to synchronize the pending stop operation via
1615 * snd_usb_endpoint_sync_pending_stop().
1617 void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep, bool keep_pending)
1622 usb_audio_dbg(ep->chip, "Stopping %s EP 0x%x (running %d)\n",
1623 ep_type_name(ep->type), ep->ep_num,
1624 atomic_read(&ep->running));
1626 if (snd_BUG_ON(!atomic_read(&ep->running)))
1629 if (!atomic_dec_return(&ep->running)) {
1630 if (ep->sync_source)
1631 WRITE_ONCE(ep->sync_source->sync_sink, NULL);
1632 stop_urbs(ep, false, keep_pending);
1634 if (!atomic_dec_return(&ep->clock_ref->locked))
1635 ep->clock_ref->rate = 0;
1640 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1642 * @ep: the endpoint to release
1644 * This function does not care for the endpoint's running count but will tear
1645 * down all the streaming URBs immediately.
1647 void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1649 release_urbs(ep, true);
1653 * snd_usb_endpoint_free_all: Free the resources of an snd_usb_endpoint
1656 * This free all endpoints and those resources
1658 void snd_usb_endpoint_free_all(struct snd_usb_audio *chip)
1660 struct snd_usb_endpoint *ep, *en;
1661 struct snd_usb_iface_ref *ip, *in;
1662 struct snd_usb_clock_ref *cp, *cn;
1664 list_for_each_entry_safe(ep, en, &chip->ep_list, list)
1667 list_for_each_entry_safe(ip, in, &chip->iface_ref_list, list)
1670 list_for_each_entry_safe(cp, cn, &chip->clock_ref_list, list)
1675 * snd_usb_handle_sync_urb: parse an USB sync packet
1677 * @ep: the endpoint to handle the packet
1678 * @sender: the sending endpoint
1679 * @urb: the received packet
1681 * This function is called from the context of an endpoint that received
1682 * the packet and is used to let another endpoint object handle the payload.
1684 static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1685 struct snd_usb_endpoint *sender,
1686 const struct urb *urb)
1690 unsigned long flags;
1692 snd_BUG_ON(ep == sender);
1695 * In case the endpoint is operating in implicit feedback mode, prepare
1696 * a new outbound URB that has the same layout as the received packet
1697 * and add it to the list of pending urbs. queue_pending_output_urbs()
1698 * will take care of them later.
1700 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1701 atomic_read(&ep->running)) {
1703 /* implicit feedback case */
1705 struct snd_urb_ctx *in_ctx;
1706 struct snd_usb_packet_info *out_packet;
1708 in_ctx = urb->context;
1710 /* Count overall packet size */
1711 for (i = 0; i < in_ctx->packets; i++)
1712 if (urb->iso_frame_desc[i].status == 0)
1713 bytes += urb->iso_frame_desc[i].actual_length;
1716 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1717 * streaming once it received a 0-byte OUT URB
1722 spin_lock_irqsave(&ep->lock, flags);
1723 if (ep->next_packet_queued >= ARRAY_SIZE(ep->next_packet)) {
1724 spin_unlock_irqrestore(&ep->lock, flags);
1725 usb_audio_err(ep->chip,
1726 "next package FIFO overflow EP 0x%x\n",
1732 out_packet = next_packet_fifo_enqueue(ep);
1735 * Iterate through the inbound packet and prepare the lengths
1736 * for the output packet. The OUT packet we are about to send
1737 * will have the same amount of payload bytes per stride as the
1738 * IN packet we just received. Since the actual size is scaled
1739 * by the stride, use the sender stride to calculate the length
1740 * in case the number of channels differ between the implicitly
1741 * fed-back endpoint and the synchronizing endpoint.
1744 out_packet->packets = in_ctx->packets;
1745 for (i = 0; i < in_ctx->packets; i++) {
1746 if (urb->iso_frame_desc[i].status == 0)
1747 out_packet->packet_size[i] =
1748 urb->iso_frame_desc[i].actual_length / sender->stride;
1750 out_packet->packet_size[i] = 0;
1753 spin_unlock_irqrestore(&ep->lock, flags);
1754 snd_usb_queue_pending_output_urbs(ep, false);
1760 * process after playback sync complete
1762 * Full speed devices report feedback values in 10.14 format as samples
1763 * per frame, high speed devices in 16.16 format as samples per
1766 * Because the Audio Class 1 spec was written before USB 2.0, many high
1767 * speed devices use a wrong interpretation, some others use an
1768 * entirely different format.
1770 * Therefore, we cannot predict what format any particular device uses
1771 * and must detect it automatically.
1774 if (urb->iso_frame_desc[0].status != 0 ||
1775 urb->iso_frame_desc[0].actual_length < 3)
1778 f = le32_to_cpup(urb->transfer_buffer);
1779 if (urb->iso_frame_desc[0].actual_length == 3)
1787 if (unlikely(sender->tenor_fb_quirk)) {
1789 * Devices based on Tenor 8802 chipsets (TEAC UD-H01
1790 * and others) sometimes change the feedback value
1793 if (f < ep->freqn - 0x8000)
1795 else if (f > ep->freqn + 0x8000)
1797 } else if (unlikely(ep->freqshift == INT_MIN)) {
1799 * The first time we see a feedback value, determine its format
1800 * by shifting it left or right until it matches the nominal
1801 * frequency value. This assumes that the feedback does not
1802 * differ from the nominal value more than +50% or -25%.
1805 while (f < ep->freqn - ep->freqn / 4) {
1809 while (f > ep->freqn + ep->freqn / 2) {
1813 ep->freqshift = shift;
1814 } else if (ep->freqshift >= 0)
1815 f <<= ep->freqshift;
1817 f >>= -ep->freqshift;
1819 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1821 * If the frequency looks valid, set it.
1822 * This value is referred to in prepare_playback_urb().
1824 spin_lock_irqsave(&ep->lock, flags);
1826 spin_unlock_irqrestore(&ep->lock, flags);
1829 * Out of range; maybe the shift value is wrong.
1830 * Reset it so that we autodetect again the next time.
1832 ep->freqshift = INT_MIN;