1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 */ 4 5 #include <linux/gfp.h> 6 #include <linux/init.h> 7 #include <linux/ratelimit.h> 8 #include <linux/usb.h> 9 #include <linux/usb/audio.h> 10 #include <linux/slab.h> 11 12 #include <sound/core.h> 13 #include <sound/pcm.h> 14 #include <sound/pcm_params.h> 15 16 #include "usbaudio.h" 17 #include "helper.h" 18 #include "card.h" 19 #include "endpoint.h" 20 #include "pcm.h" 21 #include "clock.h" 22 #include "quirks.h" 23 24 enum { 25 EP_STATE_STOPPED, 26 EP_STATE_RUNNING, 27 EP_STATE_STOPPING, 28 }; 29 30 /* interface refcounting */ 31 struct snd_usb_iface_ref { 32 unsigned char iface; 33 bool need_setup; 34 int opened; 35 int altset; 36 struct list_head list; 37 }; 38 39 /* clock refcounting */ 40 struct snd_usb_clock_ref { 41 unsigned char clock; 42 atomic_t locked; 43 int opened; 44 int rate; 45 bool need_setup; 46 struct list_head list; 47 }; 48 49 /* 50 * snd_usb_endpoint is a model that abstracts everything related to an 51 * USB endpoint and its streaming. 52 * 53 * There are functions to activate and deactivate the streaming URBs and 54 * optional callbacks to let the pcm logic handle the actual content of the 55 * packets for playback and record. Thus, the bus streaming and the audio 56 * handlers are fully decoupled. 57 * 58 * There are two different types of endpoints in audio applications. 59 * 60 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both 61 * inbound and outbound traffic. 62 * 63 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and 64 * expect the payload to carry Q10.14 / Q16.16 formatted sync information 65 * (3 or 4 bytes). 66 * 67 * Each endpoint has to be configured prior to being used by calling 68 * snd_usb_endpoint_set_params(). 69 * 70 * The model incorporates a reference counting, so that multiple users 71 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and 72 * only the first user will effectively start the URBs, and only the last 73 * one to stop it will tear the URBs down again. 74 */ 75 76 /* 77 * convert a sampling rate into our full speed format (fs/1000 in Q16.16) 78 * this will overflow at approx 524 kHz 79 */ 80 static inline unsigned get_usb_full_speed_rate(unsigned int rate) 81 { 82 return ((rate << 13) + 62) / 125; 83 } 84 85 /* 86 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16) 87 * this will overflow at approx 4 MHz 88 */ 89 static inline unsigned get_usb_high_speed_rate(unsigned int rate) 90 { 91 return ((rate << 10) + 62) / 125; 92 } 93 94 /* 95 * release a urb data 96 */ 97 static void release_urb_ctx(struct snd_urb_ctx *u) 98 { 99 if (u->urb && u->buffer_size) 100 usb_free_coherent(u->ep->chip->dev, u->buffer_size, 101 u->urb->transfer_buffer, 102 u->urb->transfer_dma); 103 usb_free_urb(u->urb); 104 u->urb = NULL; 105 u->buffer_size = 0; 106 } 107 108 static const char *usb_error_string(int err) 109 { 110 switch (err) { 111 case -ENODEV: 112 return "no device"; 113 case -ENOENT: 114 return "endpoint not enabled"; 115 case -EPIPE: 116 return "endpoint stalled"; 117 case -ENOSPC: 118 return "not enough bandwidth"; 119 case -ESHUTDOWN: 120 return "device disabled"; 121 case -EHOSTUNREACH: 122 return "device suspended"; 123 case -EINVAL: 124 case -EAGAIN: 125 case -EFBIG: 126 case -EMSGSIZE: 127 return "internal error"; 128 default: 129 return "unknown error"; 130 } 131 } 132 133 static inline bool ep_state_running(struct snd_usb_endpoint *ep) 134 { 135 return atomic_read(&ep->state) == EP_STATE_RUNNING; 136 } 137 138 static inline bool ep_state_update(struct snd_usb_endpoint *ep, int old, int new) 139 { 140 return atomic_try_cmpxchg(&ep->state, &old, new); 141 } 142 143 /** 144 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type 145 * 146 * @ep: The snd_usb_endpoint 147 * 148 * Determine whether an endpoint is driven by an implicit feedback 149 * data endpoint source. 150 */ 151 int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep) 152 { 153 return ep->implicit_fb_sync && usb_pipeout(ep->pipe); 154 } 155 156 /* 157 * Return the number of samples to be sent in the next packet 158 * for streaming based on information derived from sync endpoints 159 * 160 * This won't be used for implicit feedback which takes the packet size 161 * returned from the sync source 162 */ 163 static int synced_next_packet_size(struct snd_usb_endpoint *ep, 164 unsigned int avail) 165 { 166 unsigned int phase; 167 int ret; 168 169 if (ep->fill_max) 170 return ep->maxframesize; 171 172 guard(spinlock_irqsave)(&ep->lock); 173 phase = (ep->phase & 0xffff) + (ep->freqm << ep->datainterval); 174 ret = min(phase >> 16, ep->maxframesize); 175 if (avail && ret >= avail) 176 ret = -EAGAIN; 177 else 178 ep->phase = phase; 179 return ret; 180 } 181 182 /* 183 * Return the number of samples to be sent in the next packet 184 * for adaptive and synchronous endpoints 185 */ 186 static int next_packet_size(struct snd_usb_endpoint *ep, unsigned int avail) 187 { 188 unsigned int sample_accum; 189 int ret; 190 191 if (ep->fill_max) 192 return ep->maxframesize; 193 194 sample_accum = ep->sample_accum + ep->sample_rem; 195 if (sample_accum >= ep->pps) { 196 sample_accum -= ep->pps; 197 ret = ep->packsize[1]; 198 } else { 199 ret = ep->packsize[0]; 200 } 201 if (avail && ret >= avail) 202 ret = -EAGAIN; 203 else 204 ep->sample_accum = sample_accum; 205 206 return ret; 207 } 208 209 /* 210 * snd_usb_endpoint_next_packet_size: Return the number of samples to be sent 211 * in the next packet 212 * 213 * If the size is equal or exceeds @avail, don't proceed but return -EAGAIN 214 * Exception: @avail = 0 for skipping the check. 215 */ 216 int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep, 217 struct snd_urb_ctx *ctx, int idx, 218 unsigned int avail) 219 { 220 unsigned int packet; 221 222 packet = ctx->packet_size[idx]; 223 if (packet) { 224 packet = min(packet, ep->maxframesize); 225 if (avail && packet >= avail) 226 return -EAGAIN; 227 return packet; 228 } 229 230 if (ep->sync_source) 231 return synced_next_packet_size(ep, avail); 232 else 233 return next_packet_size(ep, avail); 234 } 235 236 static void call_retire_callback(struct snd_usb_endpoint *ep, 237 struct urb *urb) 238 { 239 struct snd_usb_substream *data_subs; 240 241 data_subs = READ_ONCE(ep->data_subs); 242 if (data_subs && ep->retire_data_urb) 243 ep->retire_data_urb(data_subs, urb); 244 } 245 246 static void retire_outbound_urb(struct snd_usb_endpoint *ep, 247 struct snd_urb_ctx *urb_ctx) 248 { 249 call_retire_callback(ep, urb_ctx->urb); 250 } 251 252 static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep, 253 struct snd_usb_endpoint *sender, 254 const struct urb *urb); 255 256 static void retire_inbound_urb(struct snd_usb_endpoint *ep, 257 struct snd_urb_ctx *urb_ctx) 258 { 259 struct urb *urb = urb_ctx->urb; 260 struct snd_usb_endpoint *sync_sink; 261 262 if (unlikely(ep->skip_packets > 0)) { 263 ep->skip_packets--; 264 return; 265 } 266 267 sync_sink = READ_ONCE(ep->sync_sink); 268 if (sync_sink) 269 snd_usb_handle_sync_urb(sync_sink, ep, urb); 270 271 call_retire_callback(ep, urb); 272 } 273 274 static inline bool has_tx_length_quirk(struct snd_usb_audio *chip) 275 { 276 return chip->quirk_flags & QUIRK_FLAG_TX_LENGTH; 277 } 278 279 static int prepare_silent_urb(struct snd_usb_endpoint *ep, 280 struct snd_urb_ctx *ctx) 281 { 282 struct urb *urb = ctx->urb; 283 unsigned int offs = 0; 284 unsigned int extra = 0; 285 __le32 packet_length; 286 int i; 287 288 /* For tx_length_quirk, put packet length at start of packet */ 289 if (has_tx_length_quirk(ep->chip)) 290 extra = sizeof(packet_length); 291 292 for (i = 0; i < ctx->packets; ++i) { 293 int length; 294 295 length = snd_usb_endpoint_next_packet_size(ep, ctx, i, 0); 296 if (length < 0) 297 return length; 298 length *= ep->stride; /* number of silent bytes */ 299 if (offs + length + extra > ctx->buffer_size) 300 break; 301 urb->iso_frame_desc[i].offset = offs; 302 urb->iso_frame_desc[i].length = length + extra; 303 if (extra) { 304 packet_length = cpu_to_le32(length); 305 memcpy(urb->transfer_buffer + offs, 306 &packet_length, sizeof(packet_length)); 307 offs += extra; 308 } 309 memset(urb->transfer_buffer + offs, 310 ep->silence_value, length); 311 offs += length; 312 } 313 314 if (!offs) 315 return -EPIPE; 316 317 urb->number_of_packets = i; 318 urb->transfer_buffer_length = offs; 319 ctx->queued = 0; 320 return 0; 321 } 322 323 /* 324 * Prepare a PLAYBACK urb for submission to the bus. 325 */ 326 static int prepare_outbound_urb(struct snd_usb_endpoint *ep, 327 struct snd_urb_ctx *ctx, 328 bool in_stream_lock) 329 { 330 struct urb *urb = ctx->urb; 331 unsigned char *cp = urb->transfer_buffer; 332 struct snd_usb_substream *data_subs; 333 334 urb->dev = ep->chip->dev; /* we need to set this at each time */ 335 336 switch (ep->type) { 337 case SND_USB_ENDPOINT_TYPE_DATA: 338 data_subs = READ_ONCE(ep->data_subs); 339 if (data_subs && ep->prepare_data_urb) 340 return ep->prepare_data_urb(data_subs, urb, in_stream_lock); 341 /* no data provider, so send silence */ 342 return prepare_silent_urb(ep, ctx); 343 344 case SND_USB_ENDPOINT_TYPE_SYNC: 345 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) { 346 /* 347 * fill the length and offset of each urb descriptor. 348 * the fixed 12.13 frequency is passed as 16.16 through the pipe. 349 */ 350 urb->iso_frame_desc[0].length = 4; 351 urb->iso_frame_desc[0].offset = 0; 352 cp[0] = ep->freqn; 353 cp[1] = ep->freqn >> 8; 354 cp[2] = ep->freqn >> 16; 355 cp[3] = ep->freqn >> 24; 356 } else { 357 /* 358 * fill the length and offset of each urb descriptor. 359 * the fixed 10.14 frequency is passed through the pipe. 360 */ 361 urb->iso_frame_desc[0].length = 3; 362 urb->iso_frame_desc[0].offset = 0; 363 cp[0] = ep->freqn >> 2; 364 cp[1] = ep->freqn >> 10; 365 cp[2] = ep->freqn >> 18; 366 } 367 368 break; 369 } 370 return 0; 371 } 372 373 /* 374 * Prepare a CAPTURE or SYNC urb for submission to the bus. 375 */ 376 static int prepare_inbound_urb(struct snd_usb_endpoint *ep, 377 struct snd_urb_ctx *urb_ctx) 378 { 379 int i, offs; 380 struct urb *urb = urb_ctx->urb; 381 382 urb->dev = ep->chip->dev; /* we need to set this at each time */ 383 384 switch (ep->type) { 385 case SND_USB_ENDPOINT_TYPE_DATA: 386 offs = 0; 387 for (i = 0; i < urb_ctx->packets; i++) { 388 urb->iso_frame_desc[i].offset = offs; 389 urb->iso_frame_desc[i].length = ep->curpacksize; 390 offs += ep->curpacksize; 391 } 392 393 urb->transfer_buffer_length = offs; 394 urb->number_of_packets = urb_ctx->packets; 395 break; 396 397 case SND_USB_ENDPOINT_TYPE_SYNC: 398 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize); 399 urb->iso_frame_desc[0].offset = 0; 400 break; 401 } 402 return 0; 403 } 404 405 /* notify an error as XRUN to the assigned PCM data substream */ 406 static bool notify_xrun(struct snd_usb_endpoint *ep) 407 { 408 struct snd_usb_substream *data_subs; 409 struct snd_pcm_substream *psubs; 410 411 data_subs = READ_ONCE(ep->data_subs); 412 if (!data_subs) 413 return false; 414 psubs = data_subs->pcm_substream; 415 if (psubs && psubs->runtime && 416 psubs->runtime->state == SNDRV_PCM_STATE_RUNNING) { 417 snd_pcm_stop_xrun(psubs); 418 return true; 419 } 420 return false; 421 } 422 423 static struct snd_usb_packet_info * 424 next_packet_fifo_enqueue(struct snd_usb_endpoint *ep) 425 { 426 struct snd_usb_packet_info *p; 427 428 p = ep->next_packet + (ep->next_packet_head + ep->next_packet_queued) % 429 ARRAY_SIZE(ep->next_packet); 430 ep->next_packet_queued++; 431 return p; 432 } 433 434 static struct snd_usb_packet_info * 435 next_packet_fifo_dequeue(struct snd_usb_endpoint *ep) 436 { 437 struct snd_usb_packet_info *p; 438 439 p = ep->next_packet + ep->next_packet_head; 440 ep->next_packet_head++; 441 ep->next_packet_head %= ARRAY_SIZE(ep->next_packet); 442 ep->next_packet_queued--; 443 return p; 444 } 445 446 static void push_back_to_ready_list(struct snd_usb_endpoint *ep, 447 struct snd_urb_ctx *ctx) 448 { 449 guard(spinlock_irqsave)(&ep->lock); 450 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs); 451 } 452 453 /* 454 * Send output urbs that have been prepared previously. URBs are dequeued 455 * from ep->ready_playback_urbs and in case there aren't any available 456 * or there are no packets that have been prepared, this function does 457 * nothing. 458 * 459 * The reason why the functionality of sending and preparing URBs is separated 460 * is that host controllers don't guarantee the order in which they return 461 * inbound and outbound packets to their submitters. 462 * 463 * This function is used both for implicit feedback endpoints and in low- 464 * latency playback mode. 465 */ 466 int snd_usb_queue_pending_output_urbs(struct snd_usb_endpoint *ep, 467 bool in_stream_lock) 468 { 469 bool implicit_fb = snd_usb_endpoint_implicit_feedback_sink(ep); 470 471 while (ep_state_running(ep)) { 472 struct snd_usb_packet_info *packet; 473 struct snd_urb_ctx *ctx = NULL; 474 int err; 475 476 scoped_guard(spinlock_irqsave, &ep->lock) { 477 if ((!implicit_fb || ep->next_packet_queued > 0) && 478 !list_empty(&ep->ready_playback_urbs)) { 479 /* take URB out of FIFO */ 480 ctx = list_first_entry(&ep->ready_playback_urbs, 481 struct snd_urb_ctx, ready_list); 482 list_del_init(&ctx->ready_list); 483 if (implicit_fb) 484 packet = next_packet_fifo_dequeue(ep); 485 } 486 } 487 488 if (ctx == NULL) 489 break; 490 491 /* copy over the length information */ 492 if (implicit_fb) { 493 ctx->packets = packet->packets; 494 memcpy(ctx->packet_size, packet->packet_size, 495 packet->packets * sizeof(packet->packet_size[0])); 496 } 497 498 /* call the data handler to fill in playback data */ 499 err = prepare_outbound_urb(ep, ctx, in_stream_lock); 500 /* can be stopped during prepare callback */ 501 if (unlikely(!ep_state_running(ep))) 502 break; 503 if (err < 0) { 504 /* push back to ready list again for -EAGAIN */ 505 if (err == -EAGAIN) { 506 push_back_to_ready_list(ep, ctx); 507 break; 508 } 509 510 if (!in_stream_lock) 511 notify_xrun(ep); 512 return -EPIPE; 513 } 514 515 if (!atomic_read(&ep->chip->shutdown)) 516 err = usb_submit_urb(ctx->urb, GFP_ATOMIC); 517 else 518 err = -ENODEV; 519 if (err < 0) { 520 if (!atomic_read(&ep->chip->shutdown)) { 521 usb_audio_err(ep->chip, 522 "Unable to submit urb #%d: %d at %s\n", 523 ctx->index, err, __func__); 524 if (!in_stream_lock) 525 notify_xrun(ep); 526 } 527 return -EPIPE; 528 } 529 530 set_bit(ctx->index, &ep->active_mask); 531 atomic_inc(&ep->submitted_urbs); 532 } 533 534 return 0; 535 } 536 537 /* 538 * complete callback for urbs 539 */ 540 static void snd_complete_urb(struct urb *urb) 541 { 542 struct snd_urb_ctx *ctx = urb->context; 543 struct snd_usb_endpoint *ep = ctx->ep; 544 int err; 545 546 if (unlikely(urb->status == -ENOENT || /* unlinked */ 547 urb->status == -ENODEV || /* device removed */ 548 urb->status == -ECONNRESET || /* unlinked */ 549 urb->status == -ESHUTDOWN)) /* device disabled */ 550 goto exit_clear; 551 /* device disconnected */ 552 if (unlikely(atomic_read(&ep->chip->shutdown))) 553 goto exit_clear; 554 555 if (unlikely(!ep_state_running(ep))) 556 goto exit_clear; 557 558 if (usb_pipeout(ep->pipe)) { 559 retire_outbound_urb(ep, ctx); 560 /* can be stopped during retire callback */ 561 if (unlikely(!ep_state_running(ep))) 562 goto exit_clear; 563 564 /* in low-latency and implicit-feedback modes, push back the 565 * URB to ready list at first, then process as much as possible 566 */ 567 if (ep->lowlatency_playback || 568 snd_usb_endpoint_implicit_feedback_sink(ep)) { 569 push_back_to_ready_list(ep, ctx); 570 clear_bit(ctx->index, &ep->active_mask); 571 snd_usb_queue_pending_output_urbs(ep, false); 572 /* decrement at last, and check xrun */ 573 if (atomic_dec_and_test(&ep->submitted_urbs) && 574 !snd_usb_endpoint_implicit_feedback_sink(ep)) 575 notify_xrun(ep); 576 return; 577 } 578 579 /* in non-lowlatency mode, no error handling for prepare */ 580 prepare_outbound_urb(ep, ctx, false); 581 /* can be stopped during prepare callback */ 582 if (unlikely(!ep_state_running(ep))) 583 goto exit_clear; 584 } else { 585 retire_inbound_urb(ep, ctx); 586 /* can be stopped during retire callback */ 587 if (unlikely(!ep_state_running(ep))) 588 goto exit_clear; 589 590 prepare_inbound_urb(ep, ctx); 591 } 592 593 if (!atomic_read(&ep->chip->shutdown)) 594 err = usb_submit_urb(urb, GFP_ATOMIC); 595 else 596 err = -ENODEV; 597 if (err == 0) 598 return; 599 600 if (!atomic_read(&ep->chip->shutdown)) { 601 if (notify_xrun(ep)) 602 usb_audio_err(ep->chip, 603 "cannot submit urb (err = %d)\n", err); 604 } 605 606 exit_clear: 607 clear_bit(ctx->index, &ep->active_mask); 608 atomic_dec(&ep->submitted_urbs); 609 } 610 611 /* 612 * Find or create a refcount object for the given interface 613 * 614 * The objects are released altogether in snd_usb_endpoint_free_all() 615 */ 616 static struct snd_usb_iface_ref * 617 iface_ref_find(struct snd_usb_audio *chip, int iface) 618 { 619 struct snd_usb_iface_ref *ip; 620 621 list_for_each_entry(ip, &chip->iface_ref_list, list) 622 if (ip->iface == iface) 623 return ip; 624 625 ip = kzalloc_obj(*ip); 626 if (!ip) 627 return NULL; 628 ip->iface = iface; 629 list_add_tail(&ip->list, &chip->iface_ref_list); 630 return ip; 631 } 632 633 /* Similarly, a refcount object for clock */ 634 static struct snd_usb_clock_ref * 635 clock_ref_find(struct snd_usb_audio *chip, int clock) 636 { 637 struct snd_usb_clock_ref *ref; 638 639 list_for_each_entry(ref, &chip->clock_ref_list, list) 640 if (ref->clock == clock) 641 return ref; 642 643 ref = kzalloc_obj(*ref); 644 if (!ref) 645 return NULL; 646 ref->clock = clock; 647 atomic_set(&ref->locked, 0); 648 list_add_tail(&ref->list, &chip->clock_ref_list); 649 return ref; 650 } 651 652 /* 653 * Get the existing endpoint object corresponding EP 654 * Returns NULL if not present. 655 */ 656 struct snd_usb_endpoint * 657 snd_usb_get_endpoint(struct snd_usb_audio *chip, int ep_num) 658 { 659 struct snd_usb_endpoint *ep; 660 661 list_for_each_entry(ep, &chip->ep_list, list) { 662 if (ep->ep_num == ep_num) 663 return ep; 664 } 665 666 return NULL; 667 } 668 669 #define ep_type_name(type) \ 670 (type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync") 671 672 /** 673 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip 674 * 675 * @chip: The chip 676 * @ep_num: The number of the endpoint to use 677 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC 678 * 679 * If the requested endpoint has not been added to the given chip before, 680 * a new instance is created. 681 * 682 * Returns zero on success or a negative error code. 683 * 684 * New endpoints will be added to chip->ep_list and freed by 685 * calling snd_usb_endpoint_free_all(). 686 * 687 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that 688 * bNumEndpoints > 1 beforehand. 689 */ 690 int snd_usb_add_endpoint(struct snd_usb_audio *chip, int ep_num, int type) 691 { 692 struct snd_usb_endpoint *ep; 693 bool is_playback; 694 695 ep = snd_usb_get_endpoint(chip, ep_num); 696 if (ep) 697 return 0; 698 699 usb_audio_dbg(chip, "Creating new %s endpoint #%x\n", 700 ep_type_name(type), 701 ep_num); 702 ep = kzalloc_obj(*ep); 703 if (!ep) 704 return -ENOMEM; 705 706 ep->chip = chip; 707 spin_lock_init(&ep->lock); 708 ep->type = type; 709 ep->ep_num = ep_num; 710 INIT_LIST_HEAD(&ep->ready_playback_urbs); 711 atomic_set(&ep->submitted_urbs, 0); 712 713 is_playback = ((ep_num & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT); 714 ep_num &= USB_ENDPOINT_NUMBER_MASK; 715 if (is_playback) 716 ep->pipe = usb_sndisocpipe(chip->dev, ep_num); 717 else 718 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num); 719 720 list_add_tail(&ep->list, &chip->ep_list); 721 return 0; 722 } 723 724 /* Set up syncinterval and maxsyncsize for a sync EP */ 725 static void endpoint_set_syncinterval(struct snd_usb_audio *chip, 726 struct snd_usb_endpoint *ep) 727 { 728 struct usb_host_interface *alts; 729 struct usb_endpoint_descriptor *desc; 730 731 alts = snd_usb_get_host_interface(chip, ep->iface, ep->altsetting); 732 if (!alts) 733 return; 734 735 desc = get_endpoint(alts, ep->ep_idx); 736 if (desc->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE && 737 desc->bRefresh >= 1 && desc->bRefresh <= 9) 738 ep->syncinterval = desc->bRefresh; 739 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) 740 ep->syncinterval = 1; 741 else if (desc->bInterval >= 1 && desc->bInterval <= 16) 742 ep->syncinterval = desc->bInterval - 1; 743 else 744 ep->syncinterval = 3; 745 746 ep->syncmaxsize = le16_to_cpu(desc->wMaxPacketSize); 747 } 748 749 static bool endpoint_compatible(struct snd_usb_endpoint *ep, 750 const struct audioformat *fp, 751 const struct snd_pcm_hw_params *params) 752 { 753 if (!ep->opened) 754 return false; 755 if (ep->cur_audiofmt != fp) 756 return false; 757 if (ep->cur_rate != params_rate(params) || 758 ep->cur_format != params_format(params) || 759 ep->cur_period_frames != params_period_size(params) || 760 ep->cur_buffer_periods != params_periods(params)) 761 return false; 762 return true; 763 } 764 765 /* 766 * Check whether the given fp and hw params are compatible with the current 767 * setup of the target EP for implicit feedback sync 768 */ 769 bool snd_usb_endpoint_compatible(struct snd_usb_audio *chip, 770 struct snd_usb_endpoint *ep, 771 const struct audioformat *fp, 772 const struct snd_pcm_hw_params *params) 773 { 774 guard(mutex)(&chip->mutex); 775 return endpoint_compatible(ep, fp, params); 776 } 777 778 /* 779 * snd_usb_endpoint_open: Open the endpoint 780 * 781 * Called from hw_params to assign the endpoint to the substream. 782 * It's reference-counted, and only the first opener is allowed to set up 783 * arbitrary parameters. The later opener must be compatible with the 784 * former opened parameters. 785 * The endpoint needs to be closed via snd_usb_endpoint_close() later. 786 * 787 * Note that this function doesn't configure the endpoint. The substream 788 * needs to set it up later via snd_usb_endpoint_set_params() and 789 * snd_usb_endpoint_prepare(). 790 */ 791 struct snd_usb_endpoint * 792 snd_usb_endpoint_open(struct snd_usb_audio *chip, 793 const struct audioformat *fp, 794 const struct snd_pcm_hw_params *params, 795 bool is_sync_ep, 796 bool fixed_rate) 797 { 798 struct snd_usb_endpoint *ep; 799 int ep_num = is_sync_ep ? fp->sync_ep : fp->endpoint; 800 801 guard(mutex)(&chip->mutex); 802 ep = snd_usb_get_endpoint(chip, ep_num); 803 if (!ep) { 804 usb_audio_err(chip, "Cannot find EP 0x%x to open\n", ep_num); 805 return NULL; 806 } 807 808 if (!ep->opened) { 809 if (is_sync_ep) { 810 ep->iface = fp->sync_iface; 811 ep->altsetting = fp->sync_altsetting; 812 ep->ep_idx = fp->sync_ep_idx; 813 } else { 814 ep->iface = fp->iface; 815 ep->altsetting = fp->altsetting; 816 ep->ep_idx = fp->ep_idx; 817 } 818 usb_audio_dbg(chip, "Open EP 0x%x, iface=%d:%d, idx=%d\n", 819 ep_num, ep->iface, ep->altsetting, ep->ep_idx); 820 821 ep->iface_ref = iface_ref_find(chip, ep->iface); 822 if (!ep->iface_ref) 823 return NULL; 824 825 if (fp->protocol != UAC_VERSION_1) { 826 ep->clock_ref = clock_ref_find(chip, fp->clock); 827 if (!ep->clock_ref) 828 return NULL; 829 ep->clock_ref->opened++; 830 } 831 832 ep->cur_audiofmt = fp; 833 ep->cur_channels = fp->channels; 834 ep->cur_rate = params_rate(params); 835 ep->cur_format = params_format(params); 836 ep->cur_frame_bytes = snd_pcm_format_physical_width(ep->cur_format) * 837 ep->cur_channels / 8; 838 ep->cur_period_frames = params_period_size(params); 839 ep->cur_period_bytes = ep->cur_period_frames * ep->cur_frame_bytes; 840 ep->cur_buffer_periods = params_periods(params); 841 842 if (ep->type == SND_USB_ENDPOINT_TYPE_SYNC) 843 endpoint_set_syncinterval(chip, ep); 844 845 ep->implicit_fb_sync = fp->implicit_fb; 846 ep->need_setup = true; 847 ep->need_prepare = true; 848 ep->fixed_rate = fixed_rate; 849 850 usb_audio_dbg(chip, " channels=%d, rate=%d, format=%s, period_bytes=%d, periods=%d, implicit_fb=%d\n", 851 ep->cur_channels, ep->cur_rate, 852 snd_pcm_format_name(ep->cur_format), 853 ep->cur_period_bytes, ep->cur_buffer_periods, 854 ep->implicit_fb_sync); 855 856 } else { 857 if (WARN_ON(!ep->iface_ref)) 858 return NULL; 859 860 if (!endpoint_compatible(ep, fp, params)) { 861 usb_audio_err(chip, "Incompatible EP setup for 0x%x\n", 862 ep_num); 863 return NULL; 864 } 865 866 usb_audio_dbg(chip, "Reopened EP 0x%x (count %d)\n", 867 ep_num, ep->opened); 868 } 869 870 if (!ep->iface_ref->opened++) 871 ep->iface_ref->need_setup = true; 872 873 ep->opened++; 874 return ep; 875 } 876 877 /* 878 * snd_usb_endpoint_set_sync: Link data and sync endpoints 879 * 880 * Pass NULL to sync_ep to unlink again 881 */ 882 void snd_usb_endpoint_set_sync(struct snd_usb_audio *chip, 883 struct snd_usb_endpoint *data_ep, 884 struct snd_usb_endpoint *sync_ep) 885 { 886 data_ep->sync_source = sync_ep; 887 } 888 889 /* 890 * Set data endpoint callbacks and the assigned data stream 891 * 892 * Called at PCM trigger and cleanups. 893 * Pass NULL to deactivate each callback. 894 */ 895 void snd_usb_endpoint_set_callback(struct snd_usb_endpoint *ep, 896 int (*prepare)(struct snd_usb_substream *subs, 897 struct urb *urb, 898 bool in_stream_lock), 899 void (*retire)(struct snd_usb_substream *subs, 900 struct urb *urb), 901 struct snd_usb_substream *data_subs) 902 { 903 ep->prepare_data_urb = prepare; 904 ep->retire_data_urb = retire; 905 if (data_subs) 906 ep->lowlatency_playback = data_subs->lowlatency_playback; 907 else 908 ep->lowlatency_playback = false; 909 WRITE_ONCE(ep->data_subs, data_subs); 910 } 911 912 static int endpoint_set_interface(struct snd_usb_audio *chip, 913 struct snd_usb_endpoint *ep, 914 bool set) 915 { 916 int altset = set ? ep->altsetting : 0; 917 int err; 918 int retries = 0; 919 const int max_retries = 5; 920 921 if (ep->iface_ref->altset == altset) 922 return 0; 923 /* already disconnected? */ 924 if (unlikely(atomic_read(&chip->shutdown))) 925 return -ENODEV; 926 927 usb_audio_dbg(chip, "Setting usb interface %d:%d for EP 0x%x\n", 928 ep->iface, altset, ep->ep_num); 929 retry: 930 err = usb_set_interface(chip->dev, ep->iface, altset); 931 if (err < 0) { 932 if (err == -EPROTO && ++retries <= max_retries) { 933 msleep(5 * (1 << (retries - 1))); 934 goto retry; 935 } 936 usb_audio_err_ratelimited( 937 chip, "%d:%d: usb_set_interface failed (%d)\n", 938 ep->iface, altset, err); 939 return err; 940 } 941 942 if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY) 943 msleep(50); 944 ep->iface_ref->altset = altset; 945 return 0; 946 } 947 948 /* 949 * snd_usb_endpoint_close: Close the endpoint 950 * 951 * Unreference the already opened endpoint via snd_usb_endpoint_open(). 952 */ 953 void snd_usb_endpoint_close(struct snd_usb_audio *chip, 954 struct snd_usb_endpoint *ep) 955 { 956 guard(mutex)(&chip->mutex); 957 usb_audio_dbg(chip, "Closing EP 0x%x (count %d)\n", 958 ep->ep_num, ep->opened); 959 960 if (!--ep->iface_ref->opened && 961 !(chip->quirk_flags & QUIRK_FLAG_IFACE_SKIP_CLOSE)) 962 endpoint_set_interface(chip, ep, false); 963 964 if (!--ep->opened) { 965 if (ep->clock_ref) { 966 if (!--ep->clock_ref->opened) 967 ep->clock_ref->rate = 0; 968 } 969 ep->iface = 0; 970 ep->altsetting = 0; 971 ep->cur_audiofmt = NULL; 972 ep->cur_rate = 0; 973 ep->iface_ref = NULL; 974 ep->clock_ref = NULL; 975 usb_audio_dbg(chip, "EP 0x%x closed\n", ep->ep_num); 976 } 977 } 978 979 /* Prepare for suspening EP, called from the main suspend handler */ 980 void snd_usb_endpoint_suspend(struct snd_usb_endpoint *ep) 981 { 982 ep->need_prepare = true; 983 if (ep->iface_ref) 984 ep->iface_ref->need_setup = true; 985 if (ep->clock_ref) 986 ep->clock_ref->rate = 0; 987 } 988 989 /* 990 * wait until all urbs are processed. 991 */ 992 static int wait_clear_urbs(struct snd_usb_endpoint *ep) 993 { 994 unsigned long end_time = jiffies + msecs_to_jiffies(1000); 995 int alive; 996 997 if (atomic_read(&ep->state) != EP_STATE_STOPPING) 998 return 0; 999 1000 do { 1001 alive = atomic_read(&ep->submitted_urbs); 1002 if (!alive) 1003 break; 1004 1005 schedule_timeout_uninterruptible(1); 1006 } while (time_before(jiffies, end_time)); 1007 1008 if (alive) 1009 usb_audio_err(ep->chip, 1010 "timeout: still %d active urbs on EP #%x\n", 1011 alive, ep->ep_num); 1012 1013 if (ep_state_update(ep, EP_STATE_STOPPING, EP_STATE_STOPPED)) { 1014 ep->sync_sink = NULL; 1015 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL); 1016 } 1017 1018 return 0; 1019 } 1020 1021 /* sync the pending stop operation; 1022 * this function itself doesn't trigger the stop operation 1023 */ 1024 void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep) 1025 { 1026 if (ep) 1027 wait_clear_urbs(ep); 1028 } 1029 1030 /* 1031 * Stop active urbs 1032 * 1033 * This function moves the EP to STOPPING state if it's being RUNNING. 1034 */ 1035 static int stop_urbs(struct snd_usb_endpoint *ep, bool force, bool keep_pending) 1036 { 1037 unsigned int i; 1038 1039 if (!force && atomic_read(&ep->running)) 1040 return -EBUSY; 1041 1042 if (!ep_state_update(ep, EP_STATE_RUNNING, EP_STATE_STOPPING)) 1043 return 0; 1044 1045 scoped_guard(spinlock_irqsave, &ep->lock) { 1046 INIT_LIST_HEAD(&ep->ready_playback_urbs); 1047 ep->next_packet_head = 0; 1048 ep->next_packet_queued = 0; 1049 } 1050 1051 if (keep_pending) 1052 return 0; 1053 1054 for (i = 0; i < ep->nurbs; i++) { 1055 if (test_bit(i, &ep->active_mask)) { 1056 if (!test_and_set_bit(i, &ep->unlink_mask)) { 1057 struct urb *u = ep->urb[i].urb; 1058 usb_unlink_urb(u); 1059 } 1060 } 1061 } 1062 1063 return 0; 1064 } 1065 1066 /* 1067 * release an endpoint's urbs 1068 */ 1069 static int release_urbs(struct snd_usb_endpoint *ep, bool force) 1070 { 1071 int i, err; 1072 1073 /* route incoming urbs to nirvana */ 1074 snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL); 1075 1076 /* stop and unlink urbs */ 1077 err = stop_urbs(ep, force, false); 1078 if (err) 1079 return err; 1080 1081 wait_clear_urbs(ep); 1082 1083 for (i = 0; i < ep->nurbs; i++) 1084 release_urb_ctx(&ep->urb[i]); 1085 1086 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4, 1087 ep->syncbuf, ep->sync_dma); 1088 1089 ep->syncbuf = NULL; 1090 ep->nurbs = 0; 1091 return 0; 1092 } 1093 1094 /* 1095 * configure a data endpoint 1096 */ 1097 static int data_ep_set_params(struct snd_usb_endpoint *ep) 1098 { 1099 struct snd_usb_audio *chip = ep->chip; 1100 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb; 1101 unsigned int max_packs_per_period, urbs_per_period, urb_packs; 1102 unsigned int max_urbs, i; 1103 const struct audioformat *fmt = ep->cur_audiofmt; 1104 int frame_bits = ep->cur_frame_bytes * 8; 1105 int tx_length_quirk = (has_tx_length_quirk(chip) && 1106 usb_pipeout(ep->pipe)); 1107 1108 usb_audio_dbg(chip, "Setting params for data EP 0x%x, pipe 0x%x\n", 1109 ep->ep_num, ep->pipe); 1110 1111 if (ep->cur_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) { 1112 /* 1113 * When operating in DSD DOP mode, the size of a sample frame 1114 * in hardware differs from the actual physical format width 1115 * because we need to make room for the DOP markers. 1116 */ 1117 frame_bits += ep->cur_channels << 3; 1118 } 1119 1120 ep->datainterval = fmt->datainterval; 1121 ep->stride = frame_bits >> 3; 1122 1123 switch (ep->cur_format) { 1124 case SNDRV_PCM_FORMAT_U8: 1125 ep->silence_value = 0x80; 1126 break; 1127 case SNDRV_PCM_FORMAT_DSD_U8: 1128 case SNDRV_PCM_FORMAT_DSD_U16_LE: 1129 case SNDRV_PCM_FORMAT_DSD_U32_LE: 1130 case SNDRV_PCM_FORMAT_DSD_U16_BE: 1131 case SNDRV_PCM_FORMAT_DSD_U32_BE: 1132 ep->silence_value = 0x69; 1133 break; 1134 default: 1135 ep->silence_value = 0; 1136 } 1137 1138 /* assume max. frequency is 50% higher than nominal */ 1139 ep->freqmax = ep->freqn + (ep->freqn >> 1); 1140 /* Round up freqmax to nearest integer in order to calculate maximum 1141 * packet size, which must represent a whole number of frames. 1142 * This is accomplished by adding 0x0.ffff before converting the 1143 * Q16.16 format into integer. 1144 * In order to accurately calculate the maximum packet size when 1145 * the data interval is more than 1 (i.e. ep->datainterval > 0), 1146 * multiply by the data interval prior to rounding. For instance, 1147 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125) 1148 * frames with a data interval of 1, but 11 (10.25) frames with a 1149 * data interval of 2. 1150 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the 1151 * maximum datainterval value of 3, at USB full speed, higher for 1152 * USB high speed, noting that ep->freqmax is in units of 1153 * frames per packet in Q16.16 format.) 1154 */ 1155 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) * 1156 (frame_bits >> 3); 1157 if (tx_length_quirk) 1158 maxsize += sizeof(__le32); /* Space for length descriptor */ 1159 /* but wMaxPacketSize might reduce this */ 1160 if (ep->maxpacksize && ep->maxpacksize < maxsize) { 1161 /* whatever fits into a max. size packet */ 1162 unsigned int data_maxsize = maxsize = ep->maxpacksize; 1163 1164 if (tx_length_quirk) 1165 /* Need to remove the length descriptor to calc freq */ 1166 data_maxsize -= sizeof(__le32); 1167 ep->freqmax = (data_maxsize / (frame_bits >> 3)) 1168 << (16 - ep->datainterval); 1169 } 1170 1171 if (ep->fill_max) { 1172 ep->curpacksize = ep->maxpacksize; 1173 maxsize = ep->curpacksize; 1174 } else { 1175 ep->curpacksize = maxsize; 1176 } 1177 1178 if (snd_usb_get_speed(chip->dev) != USB_SPEED_FULL) { 1179 packs_per_ms = 8 >> ep->datainterval; 1180 max_packs_per_urb = MAX_PACKS_HS; 1181 } else { 1182 packs_per_ms = 1; 1183 max_packs_per_urb = MAX_PACKS; 1184 } 1185 if (ep->sync_source && !ep->implicit_fb_sync) 1186 max_packs_per_urb = min(max_packs_per_urb, 1187 1U << ep->sync_source->syncinterval); 1188 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval); 1189 1190 /* 1191 * Capture endpoints need to use small URBs because there's no way 1192 * to tell in advance where the next period will end, and we don't 1193 * want the next URB to complete much after the period ends. 1194 * 1195 * Playback endpoints with implicit sync much use the same parameters 1196 * as their corresponding capture endpoint. 1197 */ 1198 if (usb_pipein(ep->pipe) || ep->implicit_fb_sync) { 1199 1200 /* make capture URBs <= 1 ms and smaller than a period */ 1201 urb_packs = min(max_packs_per_urb, packs_per_ms); 1202 while (urb_packs > 1 && urb_packs * maxsize >= ep->cur_period_bytes) 1203 urb_packs >>= 1; 1204 ep->nurbs = MAX_URBS; 1205 1206 /* 1207 * Playback endpoints without implicit sync are adjusted so that 1208 * a period fits as evenly as possible in the smallest number of 1209 * URBs. The total number of URBs is adjusted to the size of the 1210 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits. 1211 */ 1212 } else { 1213 /* determine how small a packet can be */ 1214 minsize = (ep->freqn >> (16 - ep->datainterval)) * 1215 (frame_bits >> 3); 1216 /* with sync from device, assume it can be 12% lower */ 1217 if (ep->sync_source) 1218 minsize -= minsize >> 3; 1219 minsize = max(minsize, 1u); 1220 1221 /* how many packets will contain an entire ALSA period? */ 1222 max_packs_per_period = DIV_ROUND_UP(ep->cur_period_bytes, minsize); 1223 1224 /* how many URBs will contain a period? */ 1225 urbs_per_period = DIV_ROUND_UP(max_packs_per_period, 1226 max_packs_per_urb); 1227 /* how many packets are needed in each URB? */ 1228 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period); 1229 1230 /* limit the number of frames in a single URB */ 1231 ep->max_urb_frames = DIV_ROUND_UP(ep->cur_period_frames, 1232 urbs_per_period); 1233 1234 /* try to use enough URBs to contain an entire ALSA buffer */ 1235 max_urbs = min((unsigned) MAX_URBS, 1236 MAX_QUEUE * packs_per_ms / urb_packs); 1237 ep->nurbs = min(max_urbs, urbs_per_period * ep->cur_buffer_periods); 1238 } 1239 1240 /* allocate and initialize data urbs */ 1241 for (i = 0; i < ep->nurbs; i++) { 1242 struct snd_urb_ctx *u = &ep->urb[i]; 1243 u->index = i; 1244 u->ep = ep; 1245 u->packets = urb_packs; 1246 u->buffer_size = maxsize * u->packets; 1247 1248 if (fmt->fmt_type == UAC_FORMAT_TYPE_II) 1249 u->packets++; /* for transfer delimiter */ 1250 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL); 1251 if (!u->urb) 1252 goto out_of_memory; 1253 1254 u->urb->transfer_buffer = 1255 usb_alloc_coherent(chip->dev, u->buffer_size, 1256 GFP_KERNEL, &u->urb->transfer_dma); 1257 if (!u->urb->transfer_buffer) 1258 goto out_of_memory; 1259 u->urb->pipe = ep->pipe; 1260 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP; 1261 u->urb->interval = 1 << ep->datainterval; 1262 u->urb->context = u; 1263 u->urb->complete = snd_complete_urb; 1264 INIT_LIST_HEAD(&u->ready_list); 1265 } 1266 1267 return 0; 1268 1269 out_of_memory: 1270 release_urbs(ep, false); 1271 return -ENOMEM; 1272 } 1273 1274 /* 1275 * configure a sync endpoint 1276 */ 1277 static int sync_ep_set_params(struct snd_usb_endpoint *ep) 1278 { 1279 struct snd_usb_audio *chip = ep->chip; 1280 int i; 1281 1282 usb_audio_dbg(chip, "Setting params for sync EP 0x%x, pipe 0x%x\n", 1283 ep->ep_num, ep->pipe); 1284 1285 ep->syncbuf = usb_alloc_coherent(chip->dev, SYNC_URBS * 4, 1286 GFP_KERNEL, &ep->sync_dma); 1287 if (!ep->syncbuf) 1288 return -ENOMEM; 1289 1290 ep->nurbs = SYNC_URBS; 1291 for (i = 0; i < SYNC_URBS; i++) { 1292 struct snd_urb_ctx *u = &ep->urb[i]; 1293 u->index = i; 1294 u->ep = ep; 1295 u->packets = 1; 1296 u->urb = usb_alloc_urb(1, GFP_KERNEL); 1297 if (!u->urb) 1298 goto out_of_memory; 1299 u->urb->transfer_buffer = ep->syncbuf + i * 4; 1300 u->urb->transfer_dma = ep->sync_dma + i * 4; 1301 u->urb->transfer_buffer_length = 4; 1302 u->urb->pipe = ep->pipe; 1303 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP; 1304 u->urb->number_of_packets = 1; 1305 u->urb->interval = 1 << ep->syncinterval; 1306 u->urb->context = u; 1307 u->urb->complete = snd_complete_urb; 1308 } 1309 1310 return 0; 1311 1312 out_of_memory: 1313 release_urbs(ep, false); 1314 return -ENOMEM; 1315 } 1316 1317 /* update the rate of the referred clock; return the actual rate */ 1318 static int update_clock_ref_rate(struct snd_usb_audio *chip, 1319 struct snd_usb_endpoint *ep) 1320 { 1321 struct snd_usb_clock_ref *clock = ep->clock_ref; 1322 int rate = ep->cur_rate; 1323 1324 if (!clock || clock->rate == rate) 1325 return rate; 1326 if (clock->rate) { 1327 if (atomic_read(&clock->locked)) 1328 return clock->rate; 1329 if (clock->rate != rate) { 1330 usb_audio_err(chip, "Mismatched sample rate %d vs %d for EP 0x%x\n", 1331 clock->rate, rate, ep->ep_num); 1332 return clock->rate; 1333 } 1334 } 1335 clock->rate = rate; 1336 clock->need_setup = true; 1337 return rate; 1338 } 1339 1340 /* 1341 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint 1342 * 1343 * It's called either from hw_params callback. 1344 * Determine the number of URBs to be used on this endpoint. 1345 * An endpoint must be configured before it can be started. 1346 * An endpoint that is already running can not be reconfigured. 1347 */ 1348 int snd_usb_endpoint_set_params(struct snd_usb_audio *chip, 1349 struct snd_usb_endpoint *ep) 1350 { 1351 const struct audioformat *fmt = ep->cur_audiofmt; 1352 int err; 1353 1354 guard(mutex)(&chip->mutex); 1355 if (!ep->need_setup) 1356 return 0; 1357 1358 /* release old buffers, if any */ 1359 err = release_urbs(ep, false); 1360 if (err < 0) 1361 return err; 1362 1363 ep->datainterval = fmt->datainterval; 1364 ep->maxpacksize = fmt->maxpacksize; 1365 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX); 1366 1367 if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) { 1368 ep->freqn = get_usb_full_speed_rate(ep->cur_rate); 1369 ep->pps = 1000 >> ep->datainterval; 1370 } else { 1371 ep->freqn = get_usb_high_speed_rate(ep->cur_rate); 1372 ep->pps = 8000 >> ep->datainterval; 1373 } 1374 1375 ep->sample_rem = ep->cur_rate % ep->pps; 1376 ep->packsize[0] = ep->cur_rate / ep->pps; 1377 ep->packsize[1] = (ep->cur_rate + (ep->pps - 1)) / ep->pps; 1378 if (ep->packsize[1] > ep->maxpacksize) { 1379 usb_audio_dbg(chip, "Too small maxpacksize %u for rate %u / pps %u\n", 1380 ep->maxpacksize, ep->cur_rate, ep->pps); 1381 return -EINVAL; 1382 } 1383 1384 /* calculate the frequency in 16.16 format */ 1385 ep->freqm = ep->freqn; 1386 ep->freqshift = INT_MIN; 1387 1388 ep->phase = 0; 1389 1390 switch (ep->type) { 1391 case SND_USB_ENDPOINT_TYPE_DATA: 1392 err = data_ep_set_params(ep); 1393 break; 1394 case SND_USB_ENDPOINT_TYPE_SYNC: 1395 err = sync_ep_set_params(ep); 1396 break; 1397 default: 1398 err = -EINVAL; 1399 } 1400 1401 usb_audio_dbg(chip, "Set up %d URBS, ret=%d\n", ep->nurbs, err); 1402 1403 if (err < 0) 1404 return err; 1405 1406 /* some unit conversions in runtime */ 1407 ep->maxframesize = ep->maxpacksize / ep->cur_frame_bytes; 1408 ep->curframesize = ep->curpacksize / ep->cur_frame_bytes; 1409 1410 ep->packsize[0] = min(ep->packsize[0], ep->maxframesize); 1411 ep->packsize[1] = min(ep->packsize[1], ep->maxframesize); 1412 1413 err = update_clock_ref_rate(chip, ep); 1414 if (err >= 0) { 1415 ep->need_setup = false; 1416 err = 0; 1417 } 1418 1419 return err; 1420 } 1421 1422 static int init_sample_rate(struct snd_usb_audio *chip, 1423 struct snd_usb_endpoint *ep) 1424 { 1425 struct snd_usb_clock_ref *clock = ep->clock_ref; 1426 int rate, err; 1427 1428 rate = update_clock_ref_rate(chip, ep); 1429 if (rate < 0) 1430 return rate; 1431 if (clock && !clock->need_setup) 1432 return 0; 1433 1434 if (!ep->fixed_rate) { 1435 err = snd_usb_init_sample_rate(chip, ep->cur_audiofmt, rate); 1436 if (err < 0) { 1437 if (clock) 1438 clock->rate = 0; /* reset rate */ 1439 return err; 1440 } 1441 } 1442 1443 if (clock) 1444 clock->need_setup = false; 1445 return 0; 1446 } 1447 1448 /* 1449 * snd_usb_endpoint_prepare: Prepare the endpoint 1450 * 1451 * This function sets up the EP to be fully usable state. 1452 * It's called either from prepare callback. 1453 * The function checks need_setup flag, and performs nothing unless needed, 1454 * so it's safe to call this multiple times. 1455 * 1456 * This returns zero if unchanged, 1 if the configuration has changed, 1457 * or a negative error code. 1458 */ 1459 int snd_usb_endpoint_prepare(struct snd_usb_audio *chip, 1460 struct snd_usb_endpoint *ep) 1461 { 1462 bool iface_first; 1463 int err = 0; 1464 1465 guard(mutex)(&chip->mutex); 1466 if (WARN_ON(!ep->iface_ref)) 1467 return 0; 1468 if (!ep->need_prepare) 1469 return 0; 1470 1471 /* If the interface has been already set up, just set EP parameters */ 1472 if (!ep->iface_ref->need_setup) { 1473 /* sample rate setup of UAC1 is per endpoint, and we need 1474 * to update at each EP configuration 1475 */ 1476 if (ep->cur_audiofmt->protocol == UAC_VERSION_1) { 1477 err = init_sample_rate(chip, ep); 1478 if (err < 0) 1479 return err; 1480 } 1481 goto done; 1482 } 1483 1484 /* Need to deselect altsetting at first */ 1485 endpoint_set_interface(chip, ep, false); 1486 1487 /* Some UAC1 devices (e.g. Yamaha THR10) need the host interface 1488 * to be set up before parameter setups 1489 */ 1490 iface_first = ep->cur_audiofmt->protocol == UAC_VERSION_1; 1491 /* Workaround for devices that require the interface setup at first like UAC1 */ 1492 if (chip->quirk_flags & QUIRK_FLAG_SET_IFACE_FIRST) 1493 iface_first = true; 1494 if (iface_first) { 1495 err = endpoint_set_interface(chip, ep, true); 1496 if (err < 0) 1497 return err; 1498 } 1499 1500 err = snd_usb_select_mode_quirk(chip, ep->cur_audiofmt); 1501 if (err < 0) 1502 return err; 1503 1504 err = snd_usb_init_pitch(chip, ep->cur_audiofmt); 1505 if (err < 0) 1506 return err; 1507 1508 err = init_sample_rate(chip, ep); 1509 if (err < 0) 1510 return err; 1511 1512 /* for UAC2/3, enable the interface altset here at last */ 1513 if (!iface_first) { 1514 err = endpoint_set_interface(chip, ep, true); 1515 if (err < 0) 1516 return err; 1517 } 1518 1519 ep->iface_ref->need_setup = false; 1520 1521 done: 1522 ep->need_prepare = false; 1523 return 1; 1524 } 1525 EXPORT_SYMBOL_GPL(snd_usb_endpoint_prepare); 1526 1527 /* get the current rate set to the given clock by any endpoint */ 1528 int snd_usb_endpoint_get_clock_rate(struct snd_usb_audio *chip, int clock) 1529 { 1530 struct snd_usb_clock_ref *ref; 1531 int rate = 0; 1532 1533 if (!clock) 1534 return 0; 1535 guard(mutex)(&chip->mutex); 1536 list_for_each_entry(ref, &chip->clock_ref_list, list) { 1537 if (ref->clock == clock) { 1538 rate = ref->rate; 1539 break; 1540 } 1541 } 1542 return rate; 1543 } 1544 1545 /** 1546 * snd_usb_endpoint_start: start an snd_usb_endpoint 1547 * 1548 * @ep: the endpoint to start 1549 * 1550 * A call to this function will increment the running count of the endpoint. 1551 * In case it is not already running, the URBs for this endpoint will be 1552 * submitted. Otherwise, this function does nothing. 1553 * 1554 * Must be balanced to calls of snd_usb_endpoint_stop(). 1555 * 1556 * Returns an error if the URB submission failed, 0 in all other cases. 1557 */ 1558 int snd_usb_endpoint_start(struct snd_usb_endpoint *ep) 1559 { 1560 bool is_playback = usb_pipeout(ep->pipe); 1561 int err; 1562 unsigned int i; 1563 1564 if (atomic_read(&ep->chip->shutdown)) 1565 return -EBADFD; 1566 1567 if (ep->sync_source) 1568 WRITE_ONCE(ep->sync_source->sync_sink, ep); 1569 1570 usb_audio_dbg(ep->chip, "Starting %s EP 0x%x (running %d)\n", 1571 ep_type_name(ep->type), ep->ep_num, 1572 atomic_read(&ep->running)); 1573 1574 /* already running? */ 1575 if (atomic_inc_return(&ep->running) != 1) 1576 return 0; 1577 1578 if (ep->clock_ref) 1579 atomic_inc(&ep->clock_ref->locked); 1580 1581 ep->active_mask = 0; 1582 ep->unlink_mask = 0; 1583 ep->phase = 0; 1584 ep->sample_accum = 0; 1585 1586 snd_usb_endpoint_start_quirk(ep); 1587 1588 /* 1589 * If this endpoint has a data endpoint as implicit feedback source, 1590 * don't start the urbs here. Instead, mark them all as available, 1591 * wait for the record urbs to return and queue the playback urbs 1592 * from that context. 1593 */ 1594 1595 if (!ep_state_update(ep, EP_STATE_STOPPED, EP_STATE_RUNNING)) 1596 goto __error; 1597 1598 if (snd_usb_endpoint_implicit_feedback_sink(ep) && 1599 !(ep->chip->quirk_flags & QUIRK_FLAG_PLAYBACK_FIRST)) { 1600 usb_audio_dbg(ep->chip, "No URB submission due to implicit fb sync\n"); 1601 i = 0; 1602 goto fill_rest; 1603 } 1604 1605 for (i = 0; i < ep->nurbs; i++) { 1606 struct urb *urb = ep->urb[i].urb; 1607 1608 if (snd_BUG_ON(!urb)) 1609 goto __error; 1610 1611 if (is_playback) 1612 err = prepare_outbound_urb(ep, urb->context, true); 1613 else 1614 err = prepare_inbound_urb(ep, urb->context); 1615 if (err < 0) { 1616 /* stop filling at applptr */ 1617 if (err == -EAGAIN) 1618 break; 1619 usb_audio_dbg(ep->chip, 1620 "EP 0x%x: failed to prepare urb: %d\n", 1621 ep->ep_num, err); 1622 goto __error; 1623 } 1624 1625 if (!atomic_read(&ep->chip->shutdown)) 1626 err = usb_submit_urb(urb, GFP_ATOMIC); 1627 else 1628 err = -ENODEV; 1629 if (err < 0) { 1630 if (!atomic_read(&ep->chip->shutdown)) 1631 usb_audio_err(ep->chip, 1632 "cannot submit urb %d, error %d: %s\n", 1633 i, err, usb_error_string(err)); 1634 goto __error; 1635 } 1636 set_bit(i, &ep->active_mask); 1637 atomic_inc(&ep->submitted_urbs); 1638 } 1639 1640 if (!i) { 1641 usb_audio_dbg(ep->chip, "XRUN at starting EP 0x%x\n", 1642 ep->ep_num); 1643 goto __error; 1644 } 1645 1646 usb_audio_dbg(ep->chip, "%d URBs submitted for EP 0x%x\n", 1647 i, ep->ep_num); 1648 1649 fill_rest: 1650 /* put the remaining URBs to ready list */ 1651 if (is_playback) { 1652 for (; i < ep->nurbs; i++) 1653 push_back_to_ready_list(ep, ep->urb + i); 1654 } 1655 1656 return 0; 1657 1658 __error: 1659 snd_usb_endpoint_stop(ep, false); 1660 return -EPIPE; 1661 } 1662 1663 /** 1664 * snd_usb_endpoint_stop: stop an snd_usb_endpoint 1665 * 1666 * @ep: the endpoint to stop (may be NULL) 1667 * @keep_pending: keep in-flight URBs 1668 * 1669 * A call to this function will decrement the running count of the endpoint. 1670 * In case the last user has requested the endpoint stop, the URBs will 1671 * actually be deactivated. 1672 * 1673 * Must be balanced to calls of snd_usb_endpoint_start(). 1674 * 1675 * The caller needs to synchronize the pending stop operation via 1676 * snd_usb_endpoint_sync_pending_stop(). 1677 */ 1678 void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep, bool keep_pending) 1679 { 1680 if (!ep) 1681 return; 1682 1683 usb_audio_dbg(ep->chip, "Stopping %s EP 0x%x (running %d)\n", 1684 ep_type_name(ep->type), ep->ep_num, 1685 atomic_read(&ep->running)); 1686 1687 if (snd_BUG_ON(!atomic_read(&ep->running))) 1688 return; 1689 1690 if (!atomic_dec_return(&ep->running)) { 1691 if (ep->sync_source) 1692 WRITE_ONCE(ep->sync_source->sync_sink, NULL); 1693 stop_urbs(ep, false, keep_pending); 1694 if (ep->clock_ref) 1695 atomic_dec(&ep->clock_ref->locked); 1696 1697 if (ep->chip->quirk_flags & QUIRK_FLAG_FORCE_IFACE_RESET && 1698 usb_pipeout(ep->pipe)) { 1699 ep->need_prepare = true; 1700 if (ep->iface_ref) 1701 ep->iface_ref->need_setup = true; 1702 } 1703 } 1704 } 1705 1706 /** 1707 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint 1708 * 1709 * @ep: the endpoint to release 1710 * 1711 * This function does not care for the endpoint's running count but will tear 1712 * down all the streaming URBs immediately. 1713 */ 1714 void snd_usb_endpoint_release(struct snd_usb_endpoint *ep) 1715 { 1716 release_urbs(ep, true); 1717 } 1718 1719 /** 1720 * snd_usb_endpoint_free_all: Free the resources of an snd_usb_endpoint 1721 * @chip: The chip 1722 * 1723 * This free all endpoints and those resources 1724 */ 1725 void snd_usb_endpoint_free_all(struct snd_usb_audio *chip) 1726 { 1727 struct snd_usb_endpoint *ep, *en; 1728 struct snd_usb_iface_ref *ip, *in; 1729 struct snd_usb_clock_ref *cp, *cn; 1730 1731 list_for_each_entry_safe(ep, en, &chip->ep_list, list) 1732 kfree(ep); 1733 1734 list_for_each_entry_safe(ip, in, &chip->iface_ref_list, list) 1735 kfree(ip); 1736 1737 list_for_each_entry_safe(cp, cn, &chip->clock_ref_list, list) 1738 kfree(cp); 1739 } 1740 1741 /* 1742 * snd_usb_handle_sync_urb: parse an USB sync packet 1743 * 1744 * @ep: the endpoint to handle the packet 1745 * @sender: the sending endpoint 1746 * @urb: the received packet 1747 * 1748 * This function is called from the context of an endpoint that received 1749 * the packet and is used to let another endpoint object handle the payload. 1750 */ 1751 static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep, 1752 struct snd_usb_endpoint *sender, 1753 const struct urb *urb) 1754 { 1755 int shift; 1756 unsigned int f; 1757 unsigned long flags; 1758 1759 snd_BUG_ON(ep == sender); 1760 1761 /* 1762 * In case the endpoint is operating in implicit feedback mode, prepare 1763 * a new outbound URB that has the same layout as the received packet 1764 * and add it to the list of pending urbs. queue_pending_output_urbs() 1765 * will take care of them later. 1766 */ 1767 if (snd_usb_endpoint_implicit_feedback_sink(ep) && 1768 atomic_read(&ep->running)) { 1769 1770 /* implicit feedback case */ 1771 int i, bytes = 0; 1772 struct snd_urb_ctx *in_ctx; 1773 struct snd_usb_packet_info *out_packet; 1774 1775 in_ctx = urb->context; 1776 1777 /* Count overall packet size */ 1778 for (i = 0; i < in_ctx->packets; i++) 1779 if (urb->iso_frame_desc[i].status == 0) 1780 bytes += urb->iso_frame_desc[i].actual_length; 1781 1782 /* 1783 * skip empty packets. At least M-Audio's Fast Track Ultra stops 1784 * streaming once it received a 0-byte OUT URB 1785 * 1786 * However, on devices where bytes==0 means every sync-source 1787 * packet errored (e.g. Behringer Flow 8 returning -EXDEV bursts 1788 * for entire capture URBs), an unconditional return starves the 1789 * IFB-fed OUT ring permanently. Such devices set 1790 * QUIRK_FLAG_IFB_SILENCE_ON_EMPTY to fall through and enqueue a 1791 * packet_info with size 0 packets, so playback emits silence 1792 * and the OUT ring keeps moving. 1793 */ 1794 if (bytes == 0 && !(ep->chip->quirk_flags & QUIRK_FLAG_IFB_SILENCE_ON_EMPTY)) 1795 return; 1796 1797 spin_lock_irqsave(&ep->lock, flags); 1798 if (ep->next_packet_queued >= ARRAY_SIZE(ep->next_packet)) { 1799 spin_unlock_irqrestore(&ep->lock, flags); 1800 if (notify_xrun(ep)) { 1801 usb_audio_err(ep->chip, 1802 "next packet FIFO overflow EP 0x%x\n", 1803 ep->ep_num); 1804 } 1805 return; 1806 } 1807 1808 out_packet = next_packet_fifo_enqueue(ep); 1809 1810 /* 1811 * Iterate through the inbound packet and prepare the lengths 1812 * for the output packet. The OUT packet we are about to send 1813 * will have the same amount of payload bytes per stride as the 1814 * IN packet we just received. Since the actual size is scaled 1815 * by the stride, use the sender stride to calculate the length 1816 * in case the number of channels differ between the implicitly 1817 * fed-back endpoint and the synchronizing endpoint. 1818 */ 1819 1820 out_packet->packets = in_ctx->packets; 1821 for (i = 0; i < in_ctx->packets; i++) { 1822 if (urb->iso_frame_desc[i].status == 0) { 1823 unsigned int frames = 1824 urb->iso_frame_desc[i].actual_length / sender->stride; 1825 out_packet->packet_size[i] = min(frames, ep->maxframesize); 1826 } else { 1827 out_packet->packet_size[i] = 0; 1828 } 1829 } 1830 1831 spin_unlock_irqrestore(&ep->lock, flags); 1832 snd_usb_queue_pending_output_urbs(ep, false); 1833 1834 return; 1835 } 1836 1837 /* 1838 * process after playback sync complete 1839 * 1840 * Full speed devices report feedback values in 10.14 format as samples 1841 * per frame, high speed devices in 16.16 format as samples per 1842 * microframe. 1843 * 1844 * Because the Audio Class 1 spec was written before USB 2.0, many high 1845 * speed devices use a wrong interpretation, some others use an 1846 * entirely different format. 1847 * 1848 * Therefore, we cannot predict what format any particular device uses 1849 * and must detect it automatically. 1850 */ 1851 1852 if (urb->iso_frame_desc[0].status != 0 || 1853 urb->iso_frame_desc[0].actual_length < 3) 1854 return; 1855 1856 f = le32_to_cpup(urb->transfer_buffer); 1857 if (urb->iso_frame_desc[0].actual_length == 3) 1858 f &= 0x00ffffff; 1859 else 1860 f &= 0x0fffffff; 1861 1862 if (f == 0) 1863 return; 1864 1865 if (unlikely(sender->tenor_fb_quirk)) { 1866 /* 1867 * Devices based on Tenor 8802 chipsets (TEAC UD-H01 1868 * and others) sometimes change the feedback value 1869 * by +/- 0x1.0000. 1870 */ 1871 if (f < ep->freqn - 0x8000) 1872 f += 0xf000; 1873 else if (f > ep->freqn + 0x8000) 1874 f -= 0xf000; 1875 } else if (unlikely(ep->freqshift == INT_MIN)) { 1876 /* 1877 * The first time we see a feedback value, determine its format 1878 * by shifting it left or right until it matches the nominal 1879 * frequency value. This assumes that the feedback does not 1880 * differ from the nominal value more than +50% or -25%. 1881 */ 1882 shift = 0; 1883 while (f < ep->freqn - ep->freqn / 4) { 1884 f <<= 1; 1885 shift++; 1886 } 1887 while (f > ep->freqn + ep->freqn / 2) { 1888 f >>= 1; 1889 shift--; 1890 } 1891 ep->freqshift = shift; 1892 } else if (ep->freqshift >= 0) 1893 f <<= ep->freqshift; 1894 else 1895 f >>= -ep->freqshift; 1896 1897 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) { 1898 /* 1899 * If the frequency looks valid, set it. 1900 * This value is referred to in prepare_playback_urb(). 1901 */ 1902 guard(spinlock_irqsave)(&ep->lock); 1903 ep->freqm = f; 1904 } else { 1905 /* 1906 * Out of range; maybe the shift value is wrong. 1907 * Reset it so that we autodetect again the next time. 1908 */ 1909 ep->freqshift = INT_MIN; 1910 } 1911 } 1912 1913