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