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;
39 * snd_usb_endpoint is a model that abstracts everything related to an
40 * USB endpoint and its streaming.
42 * There are functions to activate and deactivate the streaming URBs and
43 * optional callbacks to let the pcm logic handle the actual content of the
44 * packets for playback and record. Thus, the bus streaming and the audio
45 * handlers are fully decoupled.
47 * There are two different types of endpoints in audio applications.
49 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
50 * inbound and outbound traffic.
52 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
53 * expect the payload to carry Q10.14 / Q16.16 formatted sync information
56 * Each endpoint has to be configured prior to being used by calling
57 * snd_usb_endpoint_set_params().
59 * The model incorporates a reference counting, so that multiple users
60 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
61 * only the first user will effectively start the URBs, and only the last
62 * one to stop it will tear the URBs down again.
66 * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
67 * this will overflow at approx 524 kHz
69 static inline unsigned get_usb_full_speed_rate(unsigned int rate)
71 return ((rate << 13) + 62) / 125;
75 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
76 * this will overflow at approx 4 MHz
78 static inline unsigned get_usb_high_speed_rate(unsigned int rate)
80 return ((rate << 10) + 62) / 125;
86 static void release_urb_ctx(struct snd_urb_ctx *u)
89 usb_free_coherent(u->ep->chip->dev, u->buffer_size,
90 u->urb->transfer_buffer,
91 u->urb->transfer_dma);
96 static const char *usb_error_string(int err)
102 return "endpoint not enabled";
104 return "endpoint stalled";
106 return "not enough bandwidth";
108 return "device disabled";
110 return "device suspended";
115 return "internal error";
117 return "unknown error";
121 static inline bool ep_state_running(struct snd_usb_endpoint *ep)
123 return atomic_read(&ep->state) == EP_STATE_RUNNING;
126 static inline bool ep_state_update(struct snd_usb_endpoint *ep, int old, int new)
128 return atomic_cmpxchg(&ep->state, old, new) == old;
132 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
134 * @ep: The snd_usb_endpoint
136 * Determine whether an endpoint is driven by an implicit feedback
137 * data endpoint source.
139 int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
141 return ep->implicit_fb_sync && usb_pipeout(ep->pipe);
145 * Return the number of samples to be sent in the next packet
146 * for streaming based on information derived from sync endpoints
148 * This won't be used for implicit feedback which takes the packet size
149 * returned from the sync source
151 static int slave_next_packet_size(struct snd_usb_endpoint *ep)
157 return ep->maxframesize;
159 spin_lock_irqsave(&ep->lock, flags);
160 ep->phase = (ep->phase & 0xffff)
161 + (ep->freqm << ep->datainterval);
162 ret = min(ep->phase >> 16, ep->maxframesize);
163 spin_unlock_irqrestore(&ep->lock, flags);
169 * Return the number of samples to be sent in the next packet
170 * for adaptive and synchronous endpoints
172 static int next_packet_size(struct snd_usb_endpoint *ep)
177 return ep->maxframesize;
179 ep->sample_accum += ep->sample_rem;
180 if (ep->sample_accum >= ep->pps) {
181 ep->sample_accum -= ep->pps;
182 ret = ep->packsize[1];
184 ret = ep->packsize[0];
191 * snd_usb_endpoint_next_packet_size: Return the number of samples to be sent
194 int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep,
195 struct snd_urb_ctx *ctx, int idx)
197 if (ctx->packet_size[idx])
198 return ctx->packet_size[idx];
199 else if (ep->sync_source)
200 return slave_next_packet_size(ep);
202 return next_packet_size(ep);
205 static void call_retire_callback(struct snd_usb_endpoint *ep,
208 struct snd_usb_substream *data_subs;
210 data_subs = READ_ONCE(ep->data_subs);
211 if (data_subs && ep->retire_data_urb)
212 ep->retire_data_urb(data_subs, urb);
215 static void retire_outbound_urb(struct snd_usb_endpoint *ep,
216 struct snd_urb_ctx *urb_ctx)
218 call_retire_callback(ep, urb_ctx->urb);
221 static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
222 struct snd_usb_endpoint *sender,
223 const struct urb *urb);
225 static void retire_inbound_urb(struct snd_usb_endpoint *ep,
226 struct snd_urb_ctx *urb_ctx)
228 struct urb *urb = urb_ctx->urb;
229 struct snd_usb_endpoint *sync_sink;
231 if (unlikely(ep->skip_packets > 0)) {
236 sync_sink = READ_ONCE(ep->sync_sink);
238 snd_usb_handle_sync_urb(sync_sink, ep, urb);
240 call_retire_callback(ep, urb);
243 static void prepare_silent_urb(struct snd_usb_endpoint *ep,
244 struct snd_urb_ctx *ctx)
246 struct urb *urb = ctx->urb;
247 unsigned int offs = 0;
248 unsigned int extra = 0;
249 __le32 packet_length;
252 /* For tx_length_quirk, put packet length at start of packet */
253 if (ep->chip->tx_length_quirk)
254 extra = sizeof(packet_length);
256 for (i = 0; i < ctx->packets; ++i) {
261 counts = snd_usb_endpoint_next_packet_size(ep, ctx, i);
262 length = counts * ep->stride; /* number of silent bytes */
263 offset = offs * ep->stride + extra * i;
264 urb->iso_frame_desc[i].offset = offset;
265 urb->iso_frame_desc[i].length = length + extra;
267 packet_length = cpu_to_le32(length);
268 memcpy(urb->transfer_buffer + offset,
269 &packet_length, sizeof(packet_length));
271 memset(urb->transfer_buffer + offset + extra,
272 ep->silence_value, length);
276 urb->number_of_packets = ctx->packets;
277 urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
282 * Prepare a PLAYBACK urb for submission to the bus.
284 static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
285 struct snd_urb_ctx *ctx)
287 struct urb *urb = ctx->urb;
288 unsigned char *cp = urb->transfer_buffer;
289 struct snd_usb_substream *data_subs;
291 urb->dev = ep->chip->dev; /* we need to set this at each time */
294 case SND_USB_ENDPOINT_TYPE_DATA:
295 data_subs = READ_ONCE(ep->data_subs);
296 if (data_subs && ep->prepare_data_urb)
297 ep->prepare_data_urb(data_subs, urb);
298 else /* no data provider, so send silence */
299 prepare_silent_urb(ep, ctx);
302 case SND_USB_ENDPOINT_TYPE_SYNC:
303 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
305 * fill the length and offset of each urb descriptor.
306 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
308 urb->iso_frame_desc[0].length = 4;
309 urb->iso_frame_desc[0].offset = 0;
311 cp[1] = ep->freqn >> 8;
312 cp[2] = ep->freqn >> 16;
313 cp[3] = ep->freqn >> 24;
316 * fill the length and offset of each urb descriptor.
317 * the fixed 10.14 frequency is passed through the pipe.
319 urb->iso_frame_desc[0].length = 3;
320 urb->iso_frame_desc[0].offset = 0;
321 cp[0] = ep->freqn >> 2;
322 cp[1] = ep->freqn >> 10;
323 cp[2] = ep->freqn >> 18;
331 * Prepare a CAPTURE or SYNC urb for submission to the bus.
333 static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep,
334 struct snd_urb_ctx *urb_ctx)
337 struct urb *urb = urb_ctx->urb;
339 urb->dev = ep->chip->dev; /* we need to set this at each time */
342 case SND_USB_ENDPOINT_TYPE_DATA:
344 for (i = 0; i < urb_ctx->packets; i++) {
345 urb->iso_frame_desc[i].offset = offs;
346 urb->iso_frame_desc[i].length = ep->curpacksize;
347 offs += ep->curpacksize;
350 urb->transfer_buffer_length = offs;
351 urb->number_of_packets = urb_ctx->packets;
354 case SND_USB_ENDPOINT_TYPE_SYNC:
355 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
356 urb->iso_frame_desc[0].offset = 0;
361 /* notify an error as XRUN to the assigned PCM data substream */
362 static void notify_xrun(struct snd_usb_endpoint *ep)
364 struct snd_usb_substream *data_subs;
366 data_subs = READ_ONCE(ep->data_subs);
367 if (data_subs && data_subs->pcm_substream)
368 snd_pcm_stop_xrun(data_subs->pcm_substream);
371 static struct snd_usb_packet_info *
372 next_packet_fifo_enqueue(struct snd_usb_endpoint *ep)
374 struct snd_usb_packet_info *p;
376 p = ep->next_packet + (ep->next_packet_head + ep->next_packet_queued) %
377 ARRAY_SIZE(ep->next_packet);
378 ep->next_packet_queued++;
382 static struct snd_usb_packet_info *
383 next_packet_fifo_dequeue(struct snd_usb_endpoint *ep)
385 struct snd_usb_packet_info *p;
387 p = ep->next_packet + ep->next_packet_head;
388 ep->next_packet_head++;
389 ep->next_packet_head %= ARRAY_SIZE(ep->next_packet);
390 ep->next_packet_queued--;
395 * Send output urbs that have been prepared previously. URBs are dequeued
396 * from ep->ready_playback_urbs and in case there aren't any available
397 * or there are no packets that have been prepared, this function does
400 * The reason why the functionality of sending and preparing URBs is separated
401 * is that host controllers don't guarantee the order in which they return
402 * inbound and outbound packets to their submitters.
404 * This function is only used for implicit feedback endpoints. For endpoints
405 * driven by dedicated sync endpoints, URBs are immediately re-submitted
406 * from their completion handler.
408 static void queue_pending_output_urbs(struct snd_usb_endpoint *ep)
410 while (ep_state_running(ep)) {
413 struct snd_usb_packet_info *packet;
414 struct snd_urb_ctx *ctx = NULL;
417 spin_lock_irqsave(&ep->lock, flags);
418 if (ep->next_packet_queued > 0 &&
419 !list_empty(&ep->ready_playback_urbs)) {
420 /* take URB out of FIFO */
421 ctx = list_first_entry(&ep->ready_playback_urbs,
422 struct snd_urb_ctx, ready_list);
423 list_del_init(&ctx->ready_list);
425 packet = next_packet_fifo_dequeue(ep);
427 spin_unlock_irqrestore(&ep->lock, flags);
432 /* copy over the length information */
433 for (i = 0; i < packet->packets; i++)
434 ctx->packet_size[i] = packet->packet_size[i];
436 /* call the data handler to fill in playback data */
437 prepare_outbound_urb(ep, ctx);
439 err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
441 usb_audio_err(ep->chip,
442 "Unable to submit urb #%d: %d at %s\n",
443 ctx->index, err, __func__);
448 set_bit(ctx->index, &ep->active_mask);
453 * complete callback for urbs
455 static void snd_complete_urb(struct urb *urb)
457 struct snd_urb_ctx *ctx = urb->context;
458 struct snd_usb_endpoint *ep = ctx->ep;
462 if (unlikely(urb->status == -ENOENT || /* unlinked */
463 urb->status == -ENODEV || /* device removed */
464 urb->status == -ECONNRESET || /* unlinked */
465 urb->status == -ESHUTDOWN)) /* device disabled */
467 /* device disconnected */
468 if (unlikely(atomic_read(&ep->chip->shutdown)))
471 if (unlikely(!ep_state_running(ep)))
474 if (usb_pipeout(ep->pipe)) {
475 retire_outbound_urb(ep, ctx);
476 /* can be stopped during retire callback */
477 if (unlikely(!ep_state_running(ep)))
480 if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
481 spin_lock_irqsave(&ep->lock, flags);
482 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
483 clear_bit(ctx->index, &ep->active_mask);
484 spin_unlock_irqrestore(&ep->lock, flags);
485 queue_pending_output_urbs(ep);
489 prepare_outbound_urb(ep, ctx);
490 /* can be stopped during prepare callback */
491 if (unlikely(!ep_state_running(ep)))
494 retire_inbound_urb(ep, ctx);
495 /* can be stopped during retire callback */
496 if (unlikely(!ep_state_running(ep)))
499 prepare_inbound_urb(ep, ctx);
502 err = usb_submit_urb(urb, GFP_ATOMIC);
506 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
510 clear_bit(ctx->index, &ep->active_mask);
514 * Find or create a refcount object for the given interface
516 * The objects are released altogether in snd_usb_endpoint_free_all()
518 static struct snd_usb_iface_ref *
519 iface_ref_find(struct snd_usb_audio *chip, int iface)
521 struct snd_usb_iface_ref *ip;
523 list_for_each_entry(ip, &chip->iface_ref_list, list)
524 if (ip->iface == iface)
527 ip = kzalloc(sizeof(*ip), GFP_KERNEL);
531 list_add_tail(&ip->list, &chip->iface_ref_list);
536 * Get the existing endpoint object corresponding EP
537 * Returns NULL if not present.
539 struct snd_usb_endpoint *
540 snd_usb_get_endpoint(struct snd_usb_audio *chip, int ep_num)
542 struct snd_usb_endpoint *ep;
544 list_for_each_entry(ep, &chip->ep_list, list) {
545 if (ep->ep_num == ep_num)
552 #define ep_type_name(type) \
553 (type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync")
556 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
559 * @ep_num: The number of the endpoint to use
560 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
562 * If the requested endpoint has not been added to the given chip before,
563 * a new instance is created.
565 * Returns zero on success or a negative error code.
567 * New endpoints will be added to chip->ep_list and freed by
568 * calling snd_usb_endpoint_free_all().
570 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
571 * bNumEndpoints > 1 beforehand.
573 int snd_usb_add_endpoint(struct snd_usb_audio *chip, int ep_num, int type)
575 struct snd_usb_endpoint *ep;
578 ep = snd_usb_get_endpoint(chip, ep_num);
582 usb_audio_dbg(chip, "Creating new %s endpoint #%x\n",
585 ep = kzalloc(sizeof(*ep), GFP_KERNEL);
590 spin_lock_init(&ep->lock);
593 INIT_LIST_HEAD(&ep->ready_playback_urbs);
595 is_playback = ((ep_num & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT);
596 ep_num &= USB_ENDPOINT_NUMBER_MASK;
598 ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
600 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
602 list_add_tail(&ep->list, &chip->ep_list);
606 /* Set up syncinterval and maxsyncsize for a sync EP */
607 static void endpoint_set_syncinterval(struct snd_usb_audio *chip,
608 struct snd_usb_endpoint *ep)
610 struct usb_host_interface *alts;
611 struct usb_endpoint_descriptor *desc;
613 alts = snd_usb_get_host_interface(chip, ep->iface, ep->altsetting);
617 desc = get_endpoint(alts, ep->ep_idx);
618 if (desc->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
619 desc->bRefresh >= 1 && desc->bRefresh <= 9)
620 ep->syncinterval = desc->bRefresh;
621 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
622 ep->syncinterval = 1;
623 else if (desc->bInterval >= 1 && desc->bInterval <= 16)
624 ep->syncinterval = desc->bInterval - 1;
626 ep->syncinterval = 3;
628 ep->syncmaxsize = le16_to_cpu(desc->wMaxPacketSize);
631 static bool endpoint_compatible(struct snd_usb_endpoint *ep,
632 const struct audioformat *fp,
633 const struct snd_pcm_hw_params *params)
637 if (ep->cur_audiofmt != fp)
639 if (ep->cur_rate != params_rate(params) ||
640 ep->cur_format != params_format(params) ||
641 ep->cur_period_frames != params_period_size(params) ||
642 ep->cur_buffer_periods != params_periods(params))
648 * Check whether the given fp and hw params are compatible with the current
649 * setup of the target EP for implicit feedback sync
651 bool snd_usb_endpoint_compatible(struct snd_usb_audio *chip,
652 struct snd_usb_endpoint *ep,
653 const struct audioformat *fp,
654 const struct snd_pcm_hw_params *params)
658 mutex_lock(&chip->mutex);
659 ret = endpoint_compatible(ep, fp, params);
660 mutex_unlock(&chip->mutex);
665 * snd_usb_endpoint_open: Open the endpoint
667 * Called from hw_params to assign the endpoint to the substream.
668 * It's reference-counted, and only the first opener is allowed to set up
669 * arbitrary parameters. The later opener must be compatible with the
670 * former opened parameters.
671 * The endpoint needs to be closed via snd_usb_endpoint_close() later.
673 * Note that this function doesn't configure the endpoint. The substream
674 * needs to set it up later via snd_usb_endpoint_configure().
676 struct snd_usb_endpoint *
677 snd_usb_endpoint_open(struct snd_usb_audio *chip,
678 const struct audioformat *fp,
679 const struct snd_pcm_hw_params *params,
682 struct snd_usb_endpoint *ep;
683 int ep_num = is_sync_ep ? fp->sync_ep : fp->endpoint;
685 mutex_lock(&chip->mutex);
686 ep = snd_usb_get_endpoint(chip, ep_num);
688 usb_audio_err(chip, "Cannot find EP 0x%x to open\n", ep_num);
694 ep->iface = fp->sync_iface;
695 ep->altsetting = fp->sync_altsetting;
696 ep->ep_idx = fp->sync_ep_idx;
698 ep->iface = fp->iface;
699 ep->altsetting = fp->altsetting;
700 ep->ep_idx = fp->ep_idx;
702 usb_audio_dbg(chip, "Open EP 0x%x, iface=%d:%d, idx=%d\n",
703 ep_num, ep->iface, ep->altsetting, ep->ep_idx);
705 ep->iface_ref = iface_ref_find(chip, ep->iface);
706 if (!ep->iface_ref) {
711 ep->cur_audiofmt = fp;
712 ep->cur_channels = fp->channels;
713 ep->cur_rate = params_rate(params);
714 ep->cur_format = params_format(params);
715 ep->cur_frame_bytes = snd_pcm_format_physical_width(ep->cur_format) *
716 ep->cur_channels / 8;
717 ep->cur_period_frames = params_period_size(params);
718 ep->cur_period_bytes = ep->cur_period_frames * ep->cur_frame_bytes;
719 ep->cur_buffer_periods = params_periods(params);
721 if (ep->type == SND_USB_ENDPOINT_TYPE_SYNC)
722 endpoint_set_syncinterval(chip, ep);
724 ep->implicit_fb_sync = fp->implicit_fb;
725 ep->need_setup = true;
727 usb_audio_dbg(chip, " channels=%d, rate=%d, format=%s, period_bytes=%d, periods=%d, implicit_fb=%d\n",
728 ep->cur_channels, ep->cur_rate,
729 snd_pcm_format_name(ep->cur_format),
730 ep->cur_period_bytes, ep->cur_buffer_periods,
731 ep->implicit_fb_sync);
734 if (WARN_ON(!ep->iface_ref)) {
739 if (!endpoint_compatible(ep, fp, params)) {
740 usb_audio_err(chip, "Incompatible EP setup for 0x%x\n",
746 usb_audio_dbg(chip, "Reopened EP 0x%x (count %d)\n",
750 if (!ep->iface_ref->opened++)
751 ep->iface_ref->need_setup = true;
756 mutex_unlock(&chip->mutex);
761 * snd_usb_endpoint_set_sync: Link data and sync endpoints
763 * Pass NULL to sync_ep to unlink again
765 void snd_usb_endpoint_set_sync(struct snd_usb_audio *chip,
766 struct snd_usb_endpoint *data_ep,
767 struct snd_usb_endpoint *sync_ep)
769 data_ep->sync_source = sync_ep;
773 * Set data endpoint callbacks and the assigned data stream
775 * Called at PCM trigger and cleanups.
776 * Pass NULL to deactivate each callback.
778 void snd_usb_endpoint_set_callback(struct snd_usb_endpoint *ep,
779 void (*prepare)(struct snd_usb_substream *subs,
781 void (*retire)(struct snd_usb_substream *subs,
783 struct snd_usb_substream *data_subs)
785 ep->prepare_data_urb = prepare;
786 ep->retire_data_urb = retire;
787 WRITE_ONCE(ep->data_subs, data_subs);
790 static int endpoint_set_interface(struct snd_usb_audio *chip,
791 struct snd_usb_endpoint *ep,
794 int altset = set ? ep->altsetting : 0;
797 usb_audio_dbg(chip, "Setting usb interface %d:%d for EP 0x%x\n",
798 ep->iface, altset, ep->ep_num);
799 err = usb_set_interface(chip->dev, ep->iface, altset);
801 usb_audio_err(chip, "%d:%d: usb_set_interface failed (%d)\n",
802 ep->iface, altset, err);
806 snd_usb_set_interface_quirk(chip);
811 * snd_usb_endpoint_close: Close the endpoint
813 * Unreference the already opened endpoint via snd_usb_endpoint_open().
815 void snd_usb_endpoint_close(struct snd_usb_audio *chip,
816 struct snd_usb_endpoint *ep)
818 mutex_lock(&chip->mutex);
819 usb_audio_dbg(chip, "Closing EP 0x%x (count %d)\n",
820 ep->ep_num, ep->opened);
822 if (!--ep->iface_ref->opened)
823 endpoint_set_interface(chip, ep, false);
828 ep->cur_audiofmt = NULL;
830 ep->iface_ref = NULL;
831 usb_audio_dbg(chip, "EP 0x%x closed\n", ep->ep_num);
833 mutex_unlock(&chip->mutex);
836 /* Prepare for suspening EP, called from the main suspend handler */
837 void snd_usb_endpoint_suspend(struct snd_usb_endpoint *ep)
839 ep->need_setup = true;
841 ep->iface_ref->need_setup = true;
845 * wait until all urbs are processed.
847 static int wait_clear_urbs(struct snd_usb_endpoint *ep)
849 unsigned long end_time = jiffies + msecs_to_jiffies(1000);
852 if (atomic_read(&ep->state) != EP_STATE_STOPPING)
856 alive = bitmap_weight(&ep->active_mask, ep->nurbs);
860 schedule_timeout_uninterruptible(1);
861 } while (time_before(jiffies, end_time));
864 usb_audio_err(ep->chip,
865 "timeout: still %d active urbs on EP #%x\n",
868 if (ep_state_update(ep, EP_STATE_STOPPING, EP_STATE_STOPPED)) {
869 ep->sync_sink = NULL;
870 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
876 /* sync the pending stop operation;
877 * this function itself doesn't trigger the stop operation
879 void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
888 * This function moves the EP to STOPPING state if it's being RUNNING.
890 static int stop_urbs(struct snd_usb_endpoint *ep, bool force)
894 if (!force && atomic_read(&ep->running))
897 if (!ep_state_update(ep, EP_STATE_RUNNING, EP_STATE_STOPPING))
900 INIT_LIST_HEAD(&ep->ready_playback_urbs);
901 ep->next_packet_head = 0;
902 ep->next_packet_queued = 0;
904 for (i = 0; i < ep->nurbs; i++) {
905 if (test_bit(i, &ep->active_mask)) {
906 if (!test_and_set_bit(i, &ep->unlink_mask)) {
907 struct urb *u = ep->urb[i].urb;
917 * release an endpoint's urbs
919 static int release_urbs(struct snd_usb_endpoint *ep, bool force)
923 /* route incoming urbs to nirvana */
924 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
926 /* stop and unlink urbs */
927 err = stop_urbs(ep, force);
933 for (i = 0; i < ep->nurbs; i++)
934 release_urb_ctx(&ep->urb[i]);
936 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
937 ep->syncbuf, ep->sync_dma);
945 * configure a data endpoint
947 static int data_ep_set_params(struct snd_usb_endpoint *ep)
949 struct snd_usb_audio *chip = ep->chip;
950 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
951 unsigned int max_packs_per_period, urbs_per_period, urb_packs;
952 unsigned int max_urbs, i;
953 const struct audioformat *fmt = ep->cur_audiofmt;
954 int frame_bits = ep->cur_frame_bytes * 8;
955 int tx_length_quirk = (chip->tx_length_quirk &&
956 usb_pipeout(ep->pipe));
958 usb_audio_dbg(chip, "Setting params for data EP 0x%x, pipe 0x%x\n",
959 ep->ep_num, ep->pipe);
961 if (ep->cur_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
963 * When operating in DSD DOP mode, the size of a sample frame
964 * in hardware differs from the actual physical format width
965 * because we need to make room for the DOP markers.
967 frame_bits += ep->cur_channels << 3;
970 ep->datainterval = fmt->datainterval;
971 ep->stride = frame_bits >> 3;
973 switch (ep->cur_format) {
974 case SNDRV_PCM_FORMAT_U8:
975 ep->silence_value = 0x80;
977 case SNDRV_PCM_FORMAT_DSD_U8:
978 case SNDRV_PCM_FORMAT_DSD_U16_LE:
979 case SNDRV_PCM_FORMAT_DSD_U32_LE:
980 case SNDRV_PCM_FORMAT_DSD_U16_BE:
981 case SNDRV_PCM_FORMAT_DSD_U32_BE:
982 ep->silence_value = 0x69;
985 ep->silence_value = 0;
988 /* assume max. frequency is 50% higher than nominal */
989 ep->freqmax = ep->freqn + (ep->freqn >> 1);
990 /* Round up freqmax to nearest integer in order to calculate maximum
991 * packet size, which must represent a whole number of frames.
992 * This is accomplished by adding 0x0.ffff before converting the
993 * Q16.16 format into integer.
994 * In order to accurately calculate the maximum packet size when
995 * the data interval is more than 1 (i.e. ep->datainterval > 0),
996 * multiply by the data interval prior to rounding. For instance,
997 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
998 * frames with a data interval of 1, but 11 (10.25) frames with a
999 * data interval of 2.
1000 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
1001 * maximum datainterval value of 3, at USB full speed, higher for
1002 * USB high speed, noting that ep->freqmax is in units of
1003 * frames per packet in Q16.16 format.)
1005 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
1007 if (tx_length_quirk)
1008 maxsize += sizeof(__le32); /* Space for length descriptor */
1009 /* but wMaxPacketSize might reduce this */
1010 if (ep->maxpacksize && ep->maxpacksize < maxsize) {
1011 /* whatever fits into a max. size packet */
1012 unsigned int data_maxsize = maxsize = ep->maxpacksize;
1014 if (tx_length_quirk)
1015 /* Need to remove the length descriptor to calc freq */
1016 data_maxsize -= sizeof(__le32);
1017 ep->freqmax = (data_maxsize / (frame_bits >> 3))
1018 << (16 - ep->datainterval);
1022 ep->curpacksize = ep->maxpacksize;
1024 ep->curpacksize = maxsize;
1026 if (snd_usb_get_speed(chip->dev) != USB_SPEED_FULL) {
1027 packs_per_ms = 8 >> ep->datainterval;
1028 max_packs_per_urb = MAX_PACKS_HS;
1031 max_packs_per_urb = MAX_PACKS;
1033 if (ep->sync_source && !ep->implicit_fb_sync)
1034 max_packs_per_urb = min(max_packs_per_urb,
1035 1U << ep->sync_source->syncinterval);
1036 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
1039 * Capture endpoints need to use small URBs because there's no way
1040 * to tell in advance where the next period will end, and we don't
1041 * want the next URB to complete much after the period ends.
1043 * Playback endpoints with implicit sync much use the same parameters
1044 * as their corresponding capture endpoint.
1046 if (usb_pipein(ep->pipe) || ep->implicit_fb_sync) {
1048 urb_packs = packs_per_ms;
1050 * Wireless devices can poll at a max rate of once per 4ms.
1051 * For dataintervals less than 5, increase the packet count to
1052 * allow the host controller to use bursting to fill in the
1055 if (snd_usb_get_speed(chip->dev) == USB_SPEED_WIRELESS) {
1056 int interval = ep->datainterval;
1057 while (interval < 5) {
1062 /* make capture URBs <= 1 ms and smaller than a period */
1063 urb_packs = min(max_packs_per_urb, urb_packs);
1064 while (urb_packs > 1 && urb_packs * maxsize >= ep->cur_period_bytes)
1066 ep->nurbs = MAX_URBS;
1069 * Playback endpoints without implicit sync are adjusted so that
1070 * a period fits as evenly as possible in the smallest number of
1071 * URBs. The total number of URBs is adjusted to the size of the
1072 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
1075 /* determine how small a packet can be */
1076 minsize = (ep->freqn >> (16 - ep->datainterval)) *
1078 /* with sync from device, assume it can be 12% lower */
1079 if (ep->sync_source)
1080 minsize -= minsize >> 3;
1081 minsize = max(minsize, 1u);
1083 /* how many packets will contain an entire ALSA period? */
1084 max_packs_per_period = DIV_ROUND_UP(ep->cur_period_bytes, minsize);
1086 /* how many URBs will contain a period? */
1087 urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
1089 /* how many packets are needed in each URB? */
1090 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
1092 /* limit the number of frames in a single URB */
1093 ep->max_urb_frames = DIV_ROUND_UP(ep->cur_period_frames,
1096 /* try to use enough URBs to contain an entire ALSA buffer */
1097 max_urbs = min((unsigned) MAX_URBS,
1098 MAX_QUEUE * packs_per_ms / urb_packs);
1099 ep->nurbs = min(max_urbs, urbs_per_period * ep->cur_buffer_periods);
1102 /* allocate and initialize data urbs */
1103 for (i = 0; i < ep->nurbs; i++) {
1104 struct snd_urb_ctx *u = &ep->urb[i];
1107 u->packets = urb_packs;
1108 u->buffer_size = maxsize * u->packets;
1110 if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
1111 u->packets++; /* for transfer delimiter */
1112 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
1116 u->urb->transfer_buffer =
1117 usb_alloc_coherent(chip->dev, u->buffer_size,
1118 GFP_KERNEL, &u->urb->transfer_dma);
1119 if (!u->urb->transfer_buffer)
1121 u->urb->pipe = ep->pipe;
1122 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1123 u->urb->interval = 1 << ep->datainterval;
1124 u->urb->context = u;
1125 u->urb->complete = snd_complete_urb;
1126 INIT_LIST_HEAD(&u->ready_list);
1132 release_urbs(ep, false);
1137 * configure a sync endpoint
1139 static int sync_ep_set_params(struct snd_usb_endpoint *ep)
1141 struct snd_usb_audio *chip = ep->chip;
1144 usb_audio_dbg(chip, "Setting params for sync EP 0x%x, pipe 0x%x\n",
1145 ep->ep_num, ep->pipe);
1147 ep->syncbuf = usb_alloc_coherent(chip->dev, SYNC_URBS * 4,
1148 GFP_KERNEL, &ep->sync_dma);
1152 for (i = 0; i < SYNC_URBS; i++) {
1153 struct snd_urb_ctx *u = &ep->urb[i];
1157 u->urb = usb_alloc_urb(1, GFP_KERNEL);
1160 u->urb->transfer_buffer = ep->syncbuf + i * 4;
1161 u->urb->transfer_dma = ep->sync_dma + i * 4;
1162 u->urb->transfer_buffer_length = 4;
1163 u->urb->pipe = ep->pipe;
1164 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
1165 u->urb->number_of_packets = 1;
1166 u->urb->interval = 1 << ep->syncinterval;
1167 u->urb->context = u;
1168 u->urb->complete = snd_complete_urb;
1171 ep->nurbs = SYNC_URBS;
1176 release_urbs(ep, false);
1181 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
1183 * Determine the number of URBs to be used on this endpoint.
1184 * An endpoint must be configured before it can be started.
1185 * An endpoint that is already running can not be reconfigured.
1187 static int snd_usb_endpoint_set_params(struct snd_usb_audio *chip,
1188 struct snd_usb_endpoint *ep)
1190 const struct audioformat *fmt = ep->cur_audiofmt;
1193 /* release old buffers, if any */
1194 err = release_urbs(ep, false);
1198 ep->datainterval = fmt->datainterval;
1199 ep->maxpacksize = fmt->maxpacksize;
1200 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
1202 if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) {
1203 ep->freqn = get_usb_full_speed_rate(ep->cur_rate);
1204 ep->pps = 1000 >> ep->datainterval;
1206 ep->freqn = get_usb_high_speed_rate(ep->cur_rate);
1207 ep->pps = 8000 >> ep->datainterval;
1210 ep->sample_rem = ep->cur_rate % ep->pps;
1211 ep->packsize[0] = ep->cur_rate / ep->pps;
1212 ep->packsize[1] = (ep->cur_rate + (ep->pps - 1)) / ep->pps;
1214 /* calculate the frequency in 16.16 format */
1215 ep->freqm = ep->freqn;
1216 ep->freqshift = INT_MIN;
1221 case SND_USB_ENDPOINT_TYPE_DATA:
1222 err = data_ep_set_params(ep);
1224 case SND_USB_ENDPOINT_TYPE_SYNC:
1225 err = sync_ep_set_params(ep);
1231 usb_audio_dbg(chip, "Set up %d URBS, ret=%d\n", ep->nurbs, err);
1236 /* some unit conversions in runtime */
1237 ep->maxframesize = ep->maxpacksize / ep->cur_frame_bytes;
1238 ep->curframesize = ep->curpacksize / ep->cur_frame_bytes;
1244 * snd_usb_endpoint_configure: Configure the endpoint
1246 * This function sets up the EP to be fully usable state.
1247 * It's called either from hw_params or prepare callback.
1248 * The function checks need_setup flag, and performs nothing unless needed,
1249 * so it's safe to call this multiple times.
1251 * This returns zero if unchanged, 1 if the configuration has changed,
1252 * or a negative error code.
1254 int snd_usb_endpoint_configure(struct snd_usb_audio *chip,
1255 struct snd_usb_endpoint *ep)
1260 mutex_lock(&chip->mutex);
1261 if (WARN_ON(!ep->iface_ref))
1263 if (!ep->need_setup)
1266 /* If the interface has been already set up, just set EP parameters */
1267 if (!ep->iface_ref->need_setup) {
1268 /* sample rate setup of UAC1 is per endpoint, and we need
1269 * to update at each EP configuration
1271 if (ep->cur_audiofmt->protocol == UAC_VERSION_1) {
1272 err = snd_usb_init_sample_rate(chip, ep->cur_audiofmt,
1277 err = snd_usb_endpoint_set_params(chip, ep);
1283 /* Need to deselect altsetting at first */
1284 endpoint_set_interface(chip, ep, false);
1286 /* Some UAC1 devices (e.g. Yamaha THR10) need the host interface
1287 * to be set up before parameter setups
1289 iface_first = ep->cur_audiofmt->protocol == UAC_VERSION_1;
1291 err = endpoint_set_interface(chip, ep, true);
1296 err = snd_usb_init_pitch(chip, ep->cur_audiofmt);
1300 err = snd_usb_init_sample_rate(chip, ep->cur_audiofmt, ep->cur_rate);
1304 err = snd_usb_endpoint_set_params(chip, ep);
1308 err = snd_usb_select_mode_quirk(chip, ep->cur_audiofmt);
1312 /* for UAC2/3, enable the interface altset here at last */
1314 err = endpoint_set_interface(chip, ep, true);
1319 ep->iface_ref->need_setup = false;
1322 ep->need_setup = false;
1326 mutex_unlock(&chip->mutex);
1331 * snd_usb_endpoint_start: start an snd_usb_endpoint
1333 * @ep: the endpoint to start
1335 * A call to this function will increment the running count of the endpoint.
1336 * In case it is not already running, the URBs for this endpoint will be
1337 * submitted. Otherwise, this function does nothing.
1339 * Must be balanced to calls of snd_usb_endpoint_stop().
1341 * Returns an error if the URB submission failed, 0 in all other cases.
1343 int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
1348 if (atomic_read(&ep->chip->shutdown))
1351 if (ep->sync_source)
1352 WRITE_ONCE(ep->sync_source->sync_sink, ep);
1354 usb_audio_dbg(ep->chip, "Starting %s EP 0x%x (running %d)\n",
1355 ep_type_name(ep->type), ep->ep_num,
1356 atomic_read(&ep->running));
1358 /* already running? */
1359 if (atomic_inc_return(&ep->running) != 1)
1362 ep->active_mask = 0;
1363 ep->unlink_mask = 0;
1365 ep->sample_accum = 0;
1367 snd_usb_endpoint_start_quirk(ep);
1370 * If this endpoint has a data endpoint as implicit feedback source,
1371 * don't start the urbs here. Instead, mark them all as available,
1372 * wait for the record urbs to return and queue the playback urbs
1373 * from that context.
1376 if (!ep_state_update(ep, EP_STATE_STOPPED, EP_STATE_RUNNING))
1379 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1380 !ep->chip->playback_first) {
1381 for (i = 0; i < ep->nurbs; i++) {
1382 struct snd_urb_ctx *ctx = ep->urb + i;
1383 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
1386 usb_audio_dbg(ep->chip, "No URB submission due to implicit fb sync\n");
1390 for (i = 0; i < ep->nurbs; i++) {
1391 struct urb *urb = ep->urb[i].urb;
1393 if (snd_BUG_ON(!urb))
1396 if (usb_pipeout(ep->pipe)) {
1397 prepare_outbound_urb(ep, urb->context);
1399 prepare_inbound_urb(ep, urb->context);
1402 err = usb_submit_urb(urb, GFP_ATOMIC);
1404 usb_audio_err(ep->chip,
1405 "cannot submit urb %d, error %d: %s\n",
1406 i, err, usb_error_string(err));
1409 set_bit(i, &ep->active_mask);
1412 usb_audio_dbg(ep->chip, "%d URBs submitted for EP 0x%x\n",
1413 ep->nurbs, ep->ep_num);
1417 snd_usb_endpoint_stop(ep);
1422 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
1424 * @ep: the endpoint to stop (may be NULL)
1426 * A call to this function will decrement the running count of the endpoint.
1427 * In case the last user has requested the endpoint stop, the URBs will
1428 * actually be deactivated.
1430 * Must be balanced to calls of snd_usb_endpoint_start().
1432 * The caller needs to synchronize the pending stop operation via
1433 * snd_usb_endpoint_sync_pending_stop().
1435 void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep)
1440 usb_audio_dbg(ep->chip, "Stopping %s EP 0x%x (running %d)\n",
1441 ep_type_name(ep->type), ep->ep_num,
1442 atomic_read(&ep->running));
1444 if (snd_BUG_ON(!atomic_read(&ep->running)))
1447 if (!atomic_dec_return(&ep->running)) {
1448 if (ep->sync_source)
1449 WRITE_ONCE(ep->sync_source->sync_sink, NULL);
1450 stop_urbs(ep, false);
1455 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
1457 * @ep: the endpoint to release
1459 * This function does not care for the endpoint's running count but will tear
1460 * down all the streaming URBs immediately.
1462 void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
1464 release_urbs(ep, true);
1468 * snd_usb_endpoint_free_all: Free the resources of an snd_usb_endpoint
1471 * This free all endpoints and those resources
1473 void snd_usb_endpoint_free_all(struct snd_usb_audio *chip)
1475 struct snd_usb_endpoint *ep, *en;
1476 struct snd_usb_iface_ref *ip, *in;
1478 list_for_each_entry_safe(ep, en, &chip->ep_list, list)
1481 list_for_each_entry_safe(ip, in, &chip->iface_ref_list, list)
1486 * snd_usb_handle_sync_urb: parse an USB sync packet
1488 * @ep: the endpoint to handle the packet
1489 * @sender: the sending endpoint
1490 * @urb: the received packet
1492 * This function is called from the context of an endpoint that received
1493 * the packet and is used to let another endpoint object handle the payload.
1495 static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
1496 struct snd_usb_endpoint *sender,
1497 const struct urb *urb)
1501 unsigned long flags;
1503 snd_BUG_ON(ep == sender);
1506 * In case the endpoint is operating in implicit feedback mode, prepare
1507 * a new outbound URB that has the same layout as the received packet
1508 * and add it to the list of pending urbs. queue_pending_output_urbs()
1509 * will take care of them later.
1511 if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
1512 atomic_read(&ep->running)) {
1514 /* implicit feedback case */
1516 struct snd_urb_ctx *in_ctx;
1517 struct snd_usb_packet_info *out_packet;
1519 in_ctx = urb->context;
1521 /* Count overall packet size */
1522 for (i = 0; i < in_ctx->packets; i++)
1523 if (urb->iso_frame_desc[i].status == 0)
1524 bytes += urb->iso_frame_desc[i].actual_length;
1527 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1528 * streaming once it received a 0-byte OUT URB
1533 spin_lock_irqsave(&ep->lock, flags);
1534 if (ep->next_packet_queued >= ARRAY_SIZE(ep->next_packet)) {
1535 spin_unlock_irqrestore(&ep->lock, flags);
1536 usb_audio_err(ep->chip,
1537 "next package FIFO overflow EP 0x%x\n",
1543 out_packet = next_packet_fifo_enqueue(ep);
1546 * Iterate through the inbound packet and prepare the lengths
1547 * for the output packet. The OUT packet we are about to send
1548 * will have the same amount of payload bytes per stride as the
1549 * IN packet we just received. Since the actual size is scaled
1550 * by the stride, use the sender stride to calculate the length
1551 * in case the number of channels differ between the implicitly
1552 * fed-back endpoint and the synchronizing endpoint.
1555 out_packet->packets = in_ctx->packets;
1556 for (i = 0; i < in_ctx->packets; i++) {
1557 if (urb->iso_frame_desc[i].status == 0)
1558 out_packet->packet_size[i] =
1559 urb->iso_frame_desc[i].actual_length / sender->stride;
1561 out_packet->packet_size[i] = 0;
1564 spin_unlock_irqrestore(&ep->lock, flags);
1565 queue_pending_output_urbs(ep);
1571 * process after playback sync complete
1573 * Full speed devices report feedback values in 10.14 format as samples
1574 * per frame, high speed devices in 16.16 format as samples per
1577 * Because the Audio Class 1 spec was written before USB 2.0, many high
1578 * speed devices use a wrong interpretation, some others use an
1579 * entirely different format.
1581 * Therefore, we cannot predict what format any particular device uses
1582 * and must detect it automatically.
1585 if (urb->iso_frame_desc[0].status != 0 ||
1586 urb->iso_frame_desc[0].actual_length < 3)
1589 f = le32_to_cpup(urb->transfer_buffer);
1590 if (urb->iso_frame_desc[0].actual_length == 3)
1598 if (unlikely(sender->tenor_fb_quirk)) {
1600 * Devices based on Tenor 8802 chipsets (TEAC UD-H01
1601 * and others) sometimes change the feedback value
1604 if (f < ep->freqn - 0x8000)
1606 else if (f > ep->freqn + 0x8000)
1608 } else if (unlikely(ep->freqshift == INT_MIN)) {
1610 * The first time we see a feedback value, determine its format
1611 * by shifting it left or right until it matches the nominal
1612 * frequency value. This assumes that the feedback does not
1613 * differ from the nominal value more than +50% or -25%.
1616 while (f < ep->freqn - ep->freqn / 4) {
1620 while (f > ep->freqn + ep->freqn / 2) {
1624 ep->freqshift = shift;
1625 } else if (ep->freqshift >= 0)
1626 f <<= ep->freqshift;
1628 f >>= -ep->freqshift;
1630 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1632 * If the frequency looks valid, set it.
1633 * This value is referred to in prepare_playback_urb().
1635 spin_lock_irqsave(&ep->lock, flags);
1637 spin_unlock_irqrestore(&ep->lock, flags);
1640 * Out of range; maybe the shift value is wrong.
1641 * Reset it so that we autodetect again the next time.
1643 ep->freqshift = INT_MIN;