1 /* 2 * This program is free software; you can redistribute it and/or modify 3 * it under the terms of the GNU General Public License as published by 4 * the Free Software Foundation; either version 2 of the License, or 5 * (at your option) any later version. 6 * 7 * This program is distributed in the hope that it will be useful, 8 * but WITHOUT ANY WARRANTY; without even the implied warranty of 9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 10 * GNU General Public License for more details. 11 * 12 * You should have received a copy of the GNU General Public License 13 * along with this program; if not, write to the Free Software 14 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 15 * 16 */ 17 18 #include <linux/gfp.h> 19 #include <linux/init.h> 20 #include <linux/ratelimit.h> 21 #include <linux/usb.h> 22 #include <linux/usb/audio.h> 23 #include <linux/slab.h> 24 25 #include <sound/core.h> 26 #include <sound/pcm.h> 27 #include <sound/pcm_params.h> 28 29 #include "usbaudio.h" 30 #include "helper.h" 31 #include "card.h" 32 #include "endpoint.h" 33 #include "pcm.h" 34 #include "quirks.h" 35 36 #define EP_FLAG_RUNNING 1 37 #define EP_FLAG_STOPPING 2 38 39 /* 40 * snd_usb_endpoint is a model that abstracts everything related to an 41 * USB endpoint and its streaming. 42 * 43 * There are functions to activate and deactivate the streaming URBs and 44 * optional callbacks to let the pcm logic handle the actual content of the 45 * packets for playback and record. Thus, the bus streaming and the audio 46 * handlers are fully decoupled. 47 * 48 * There are two different types of endpoints in audio applications. 49 * 50 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both 51 * inbound and outbound traffic. 52 * 53 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and 54 * expect the payload to carry Q10.14 / Q16.16 formatted sync information 55 * (3 or 4 bytes). 56 * 57 * Each endpoint has to be configured prior to being used by calling 58 * snd_usb_endpoint_set_params(). 59 * 60 * The model incorporates a reference counting, so that multiple users 61 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and 62 * only the first user will effectively start the URBs, and only the last 63 * one to stop it will tear the URBs down again. 64 */ 65 66 /* 67 * convert a sampling rate into our full speed format (fs/1000 in Q16.16) 68 * this will overflow at approx 524 kHz 69 */ 70 static inline unsigned get_usb_full_speed_rate(unsigned int rate) 71 { 72 return ((rate << 13) + 62) / 125; 73 } 74 75 /* 76 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16) 77 * this will overflow at approx 4 MHz 78 */ 79 static inline unsigned get_usb_high_speed_rate(unsigned int rate) 80 { 81 return ((rate << 10) + 62) / 125; 82 } 83 84 /* 85 * release a urb data 86 */ 87 static void release_urb_ctx(struct snd_urb_ctx *u) 88 { 89 if (u->buffer_size) 90 usb_free_coherent(u->ep->chip->dev, u->buffer_size, 91 u->urb->transfer_buffer, 92 u->urb->transfer_dma); 93 usb_free_urb(u->urb); 94 u->urb = NULL; 95 } 96 97 static const char *usb_error_string(int err) 98 { 99 switch (err) { 100 case -ENODEV: 101 return "no device"; 102 case -ENOENT: 103 return "endpoint not enabled"; 104 case -EPIPE: 105 return "endpoint stalled"; 106 case -ENOSPC: 107 return "not enough bandwidth"; 108 case -ESHUTDOWN: 109 return "device disabled"; 110 case -EHOSTUNREACH: 111 return "device suspended"; 112 case -EINVAL: 113 case -EAGAIN: 114 case -EFBIG: 115 case -EMSGSIZE: 116 return "internal error"; 117 default: 118 return "unknown error"; 119 } 120 } 121 122 /** 123 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type 124 * 125 * @ep: The snd_usb_endpoint 126 * 127 * Determine whether an endpoint is driven by an implicit feedback 128 * data endpoint source. 129 */ 130 int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep) 131 { 132 return ep->sync_master && 133 ep->sync_master->type == SND_USB_ENDPOINT_TYPE_DATA && 134 ep->type == SND_USB_ENDPOINT_TYPE_DATA && 135 usb_pipeout(ep->pipe); 136 } 137 138 /* 139 * For streaming based on information derived from sync endpoints, 140 * prepare_outbound_urb_sizes() will call next_packet_size() to 141 * determine the number of samples to be sent in the next packet. 142 * 143 * For implicit feedback, next_packet_size() is unused. 144 */ 145 int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep) 146 { 147 unsigned long flags; 148 int ret; 149 150 if (ep->fill_max) 151 return ep->maxframesize; 152 153 spin_lock_irqsave(&ep->lock, flags); 154 ep->phase = (ep->phase & 0xffff) 155 + (ep->freqm << ep->datainterval); 156 ret = min(ep->phase >> 16, ep->maxframesize); 157 spin_unlock_irqrestore(&ep->lock, flags); 158 159 return ret; 160 } 161 162 static void retire_outbound_urb(struct snd_usb_endpoint *ep, 163 struct snd_urb_ctx *urb_ctx) 164 { 165 if (ep->retire_data_urb) 166 ep->retire_data_urb(ep->data_subs, urb_ctx->urb); 167 } 168 169 static void retire_inbound_urb(struct snd_usb_endpoint *ep, 170 struct snd_urb_ctx *urb_ctx) 171 { 172 struct urb *urb = urb_ctx->urb; 173 174 if (unlikely(ep->skip_packets > 0)) { 175 ep->skip_packets--; 176 return; 177 } 178 179 if (ep->sync_slave) 180 snd_usb_handle_sync_urb(ep->sync_slave, ep, urb); 181 182 if (ep->retire_data_urb) 183 ep->retire_data_urb(ep->data_subs, urb); 184 } 185 186 static void prepare_silent_urb(struct snd_usb_endpoint *ep, 187 struct snd_urb_ctx *ctx) 188 { 189 struct urb *urb = ctx->urb; 190 unsigned int offs = 0; 191 unsigned int extra = 0; 192 __le32 packet_length; 193 int i; 194 195 /* For tx_length_quirk, put packet length at start of packet */ 196 if (ep->chip->tx_length_quirk) 197 extra = sizeof(packet_length); 198 199 for (i = 0; i < ctx->packets; ++i) { 200 unsigned int offset; 201 unsigned int length; 202 int counts; 203 204 if (ctx->packet_size[i]) 205 counts = ctx->packet_size[i]; 206 else 207 counts = snd_usb_endpoint_next_packet_size(ep); 208 209 length = counts * ep->stride; /* number of silent bytes */ 210 offset = offs * ep->stride + extra * i; 211 urb->iso_frame_desc[i].offset = offset; 212 urb->iso_frame_desc[i].length = length + extra; 213 if (extra) { 214 packet_length = cpu_to_le32(length); 215 memcpy(urb->transfer_buffer + offset, 216 &packet_length, sizeof(packet_length)); 217 } 218 memset(urb->transfer_buffer + offset + extra, 219 ep->silence_value, length); 220 offs += counts; 221 } 222 223 urb->number_of_packets = ctx->packets; 224 urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra; 225 } 226 227 /* 228 * Prepare a PLAYBACK urb for submission to the bus. 229 */ 230 static void prepare_outbound_urb(struct snd_usb_endpoint *ep, 231 struct snd_urb_ctx *ctx) 232 { 233 struct urb *urb = ctx->urb; 234 unsigned char *cp = urb->transfer_buffer; 235 236 urb->dev = ep->chip->dev; /* we need to set this at each time */ 237 238 switch (ep->type) { 239 case SND_USB_ENDPOINT_TYPE_DATA: 240 if (ep->prepare_data_urb) { 241 ep->prepare_data_urb(ep->data_subs, urb); 242 } else { 243 /* no data provider, so send silence */ 244 prepare_silent_urb(ep, ctx); 245 } 246 break; 247 248 case SND_USB_ENDPOINT_TYPE_SYNC: 249 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) { 250 /* 251 * fill the length and offset of each urb descriptor. 252 * the fixed 12.13 frequency is passed as 16.16 through the pipe. 253 */ 254 urb->iso_frame_desc[0].length = 4; 255 urb->iso_frame_desc[0].offset = 0; 256 cp[0] = ep->freqn; 257 cp[1] = ep->freqn >> 8; 258 cp[2] = ep->freqn >> 16; 259 cp[3] = ep->freqn >> 24; 260 } else { 261 /* 262 * fill the length and offset of each urb descriptor. 263 * the fixed 10.14 frequency is passed through the pipe. 264 */ 265 urb->iso_frame_desc[0].length = 3; 266 urb->iso_frame_desc[0].offset = 0; 267 cp[0] = ep->freqn >> 2; 268 cp[1] = ep->freqn >> 10; 269 cp[2] = ep->freqn >> 18; 270 } 271 272 break; 273 } 274 } 275 276 /* 277 * Prepare a CAPTURE or SYNC urb for submission to the bus. 278 */ 279 static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep, 280 struct snd_urb_ctx *urb_ctx) 281 { 282 int i, offs; 283 struct urb *urb = urb_ctx->urb; 284 285 urb->dev = ep->chip->dev; /* we need to set this at each time */ 286 287 switch (ep->type) { 288 case SND_USB_ENDPOINT_TYPE_DATA: 289 offs = 0; 290 for (i = 0; i < urb_ctx->packets; i++) { 291 urb->iso_frame_desc[i].offset = offs; 292 urb->iso_frame_desc[i].length = ep->curpacksize; 293 offs += ep->curpacksize; 294 } 295 296 urb->transfer_buffer_length = offs; 297 urb->number_of_packets = urb_ctx->packets; 298 break; 299 300 case SND_USB_ENDPOINT_TYPE_SYNC: 301 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize); 302 urb->iso_frame_desc[0].offset = 0; 303 break; 304 } 305 } 306 307 /* 308 * Send output urbs that have been prepared previously. URBs are dequeued 309 * from ep->ready_playback_urbs and in case there there aren't any available 310 * or there are no packets that have been prepared, this function does 311 * nothing. 312 * 313 * The reason why the functionality of sending and preparing URBs is separated 314 * is that host controllers don't guarantee the order in which they return 315 * inbound and outbound packets to their submitters. 316 * 317 * This function is only used for implicit feedback endpoints. For endpoints 318 * driven by dedicated sync endpoints, URBs are immediately re-submitted 319 * from their completion handler. 320 */ 321 static void queue_pending_output_urbs(struct snd_usb_endpoint *ep) 322 { 323 while (test_bit(EP_FLAG_RUNNING, &ep->flags)) { 324 325 unsigned long flags; 326 struct snd_usb_packet_info *uninitialized_var(packet); 327 struct snd_urb_ctx *ctx = NULL; 328 struct urb *urb; 329 int err, i; 330 331 spin_lock_irqsave(&ep->lock, flags); 332 if (ep->next_packet_read_pos != ep->next_packet_write_pos) { 333 packet = ep->next_packet + ep->next_packet_read_pos; 334 ep->next_packet_read_pos++; 335 ep->next_packet_read_pos %= MAX_URBS; 336 337 /* take URB out of FIFO */ 338 if (!list_empty(&ep->ready_playback_urbs)) 339 ctx = list_first_entry(&ep->ready_playback_urbs, 340 struct snd_urb_ctx, ready_list); 341 } 342 spin_unlock_irqrestore(&ep->lock, flags); 343 344 if (ctx == NULL) 345 return; 346 347 list_del_init(&ctx->ready_list); 348 urb = ctx->urb; 349 350 /* copy over the length information */ 351 for (i = 0; i < packet->packets; i++) 352 ctx->packet_size[i] = packet->packet_size[i]; 353 354 /* call the data handler to fill in playback data */ 355 prepare_outbound_urb(ep, ctx); 356 357 err = usb_submit_urb(ctx->urb, GFP_ATOMIC); 358 if (err < 0) 359 usb_audio_err(ep->chip, 360 "Unable to submit urb #%d: %d (urb %p)\n", 361 ctx->index, err, ctx->urb); 362 else 363 set_bit(ctx->index, &ep->active_mask); 364 } 365 } 366 367 /* 368 * complete callback for urbs 369 */ 370 static void snd_complete_urb(struct urb *urb) 371 { 372 struct snd_urb_ctx *ctx = urb->context; 373 struct snd_usb_endpoint *ep = ctx->ep; 374 struct snd_pcm_substream *substream; 375 unsigned long flags; 376 int err; 377 378 if (unlikely(urb->status == -ENOENT || /* unlinked */ 379 urb->status == -ENODEV || /* device removed */ 380 urb->status == -ECONNRESET || /* unlinked */ 381 urb->status == -ESHUTDOWN)) /* device disabled */ 382 goto exit_clear; 383 /* device disconnected */ 384 if (unlikely(atomic_read(&ep->chip->shutdown))) 385 goto exit_clear; 386 387 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags))) 388 goto exit_clear; 389 390 if (usb_pipeout(ep->pipe)) { 391 retire_outbound_urb(ep, ctx); 392 /* can be stopped during retire callback */ 393 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags))) 394 goto exit_clear; 395 396 if (snd_usb_endpoint_implicit_feedback_sink(ep)) { 397 spin_lock_irqsave(&ep->lock, flags); 398 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs); 399 spin_unlock_irqrestore(&ep->lock, flags); 400 queue_pending_output_urbs(ep); 401 402 goto exit_clear; 403 } 404 405 prepare_outbound_urb(ep, ctx); 406 } else { 407 retire_inbound_urb(ep, ctx); 408 /* can be stopped during retire callback */ 409 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags))) 410 goto exit_clear; 411 412 prepare_inbound_urb(ep, ctx); 413 } 414 415 err = usb_submit_urb(urb, GFP_ATOMIC); 416 if (err == 0) 417 return; 418 419 usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err); 420 if (ep->data_subs && ep->data_subs->pcm_substream) { 421 substream = ep->data_subs->pcm_substream; 422 snd_pcm_stop_xrun(substream); 423 } 424 425 exit_clear: 426 clear_bit(ctx->index, &ep->active_mask); 427 } 428 429 /** 430 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip 431 * 432 * @chip: The chip 433 * @alts: The USB host interface 434 * @ep_num: The number of the endpoint to use 435 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE 436 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC 437 * 438 * If the requested endpoint has not been added to the given chip before, 439 * a new instance is created. Otherwise, a pointer to the previoulsy 440 * created instance is returned. In case of any error, NULL is returned. 441 * 442 * New endpoints will be added to chip->ep_list and must be freed by 443 * calling snd_usb_endpoint_free(). 444 * 445 * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that 446 * bNumEndpoints > 1 beforehand. 447 */ 448 struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip, 449 struct usb_host_interface *alts, 450 int ep_num, int direction, int type) 451 { 452 struct snd_usb_endpoint *ep; 453 int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK; 454 455 if (WARN_ON(!alts)) 456 return NULL; 457 458 mutex_lock(&chip->mutex); 459 460 list_for_each_entry(ep, &chip->ep_list, list) { 461 if (ep->ep_num == ep_num && 462 ep->iface == alts->desc.bInterfaceNumber && 463 ep->altsetting == alts->desc.bAlternateSetting) { 464 usb_audio_dbg(ep->chip, 465 "Re-using EP %x in iface %d,%d @%p\n", 466 ep_num, ep->iface, ep->altsetting, ep); 467 goto __exit_unlock; 468 } 469 } 470 471 usb_audio_dbg(chip, "Creating new %s %s endpoint #%x\n", 472 is_playback ? "playback" : "capture", 473 type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync", 474 ep_num); 475 476 ep = kzalloc(sizeof(*ep), GFP_KERNEL); 477 if (!ep) 478 goto __exit_unlock; 479 480 ep->chip = chip; 481 spin_lock_init(&ep->lock); 482 ep->type = type; 483 ep->ep_num = ep_num; 484 ep->iface = alts->desc.bInterfaceNumber; 485 ep->altsetting = alts->desc.bAlternateSetting; 486 INIT_LIST_HEAD(&ep->ready_playback_urbs); 487 ep_num &= USB_ENDPOINT_NUMBER_MASK; 488 489 if (is_playback) 490 ep->pipe = usb_sndisocpipe(chip->dev, ep_num); 491 else 492 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num); 493 494 if (type == SND_USB_ENDPOINT_TYPE_SYNC) { 495 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE && 496 get_endpoint(alts, 1)->bRefresh >= 1 && 497 get_endpoint(alts, 1)->bRefresh <= 9) 498 ep->syncinterval = get_endpoint(alts, 1)->bRefresh; 499 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) 500 ep->syncinterval = 1; 501 else if (get_endpoint(alts, 1)->bInterval >= 1 && 502 get_endpoint(alts, 1)->bInterval <= 16) 503 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1; 504 else 505 ep->syncinterval = 3; 506 507 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize); 508 } 509 510 list_add_tail(&ep->list, &chip->ep_list); 511 512 __exit_unlock: 513 mutex_unlock(&chip->mutex); 514 515 return ep; 516 } 517 518 /* 519 * wait until all urbs are processed. 520 */ 521 static int wait_clear_urbs(struct snd_usb_endpoint *ep) 522 { 523 unsigned long end_time = jiffies + msecs_to_jiffies(1000); 524 int alive; 525 526 do { 527 alive = bitmap_weight(&ep->active_mask, ep->nurbs); 528 if (!alive) 529 break; 530 531 schedule_timeout_uninterruptible(1); 532 } while (time_before(jiffies, end_time)); 533 534 if (alive) 535 usb_audio_err(ep->chip, 536 "timeout: still %d active urbs on EP #%x\n", 537 alive, ep->ep_num); 538 clear_bit(EP_FLAG_STOPPING, &ep->flags); 539 540 ep->data_subs = NULL; 541 ep->sync_slave = NULL; 542 ep->retire_data_urb = NULL; 543 ep->prepare_data_urb = NULL; 544 545 return 0; 546 } 547 548 /* sync the pending stop operation; 549 * this function itself doesn't trigger the stop operation 550 */ 551 void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep) 552 { 553 if (ep && test_bit(EP_FLAG_STOPPING, &ep->flags)) 554 wait_clear_urbs(ep); 555 } 556 557 /* 558 * unlink active urbs. 559 */ 560 static int deactivate_urbs(struct snd_usb_endpoint *ep, bool force) 561 { 562 unsigned int i; 563 564 if (!force && atomic_read(&ep->chip->shutdown)) /* to be sure... */ 565 return -EBADFD; 566 567 clear_bit(EP_FLAG_RUNNING, &ep->flags); 568 569 INIT_LIST_HEAD(&ep->ready_playback_urbs); 570 ep->next_packet_read_pos = 0; 571 ep->next_packet_write_pos = 0; 572 573 for (i = 0; i < ep->nurbs; i++) { 574 if (test_bit(i, &ep->active_mask)) { 575 if (!test_and_set_bit(i, &ep->unlink_mask)) { 576 struct urb *u = ep->urb[i].urb; 577 usb_unlink_urb(u); 578 } 579 } 580 } 581 582 return 0; 583 } 584 585 /* 586 * release an endpoint's urbs 587 */ 588 static void release_urbs(struct snd_usb_endpoint *ep, int force) 589 { 590 int i; 591 592 /* route incoming urbs to nirvana */ 593 ep->retire_data_urb = NULL; 594 ep->prepare_data_urb = NULL; 595 596 /* stop urbs */ 597 deactivate_urbs(ep, force); 598 wait_clear_urbs(ep); 599 600 for (i = 0; i < ep->nurbs; i++) 601 release_urb_ctx(&ep->urb[i]); 602 603 if (ep->syncbuf) 604 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4, 605 ep->syncbuf, ep->sync_dma); 606 607 ep->syncbuf = NULL; 608 ep->nurbs = 0; 609 } 610 611 /* 612 * configure a data endpoint 613 */ 614 static int data_ep_set_params(struct snd_usb_endpoint *ep, 615 snd_pcm_format_t pcm_format, 616 unsigned int channels, 617 unsigned int period_bytes, 618 unsigned int frames_per_period, 619 unsigned int periods_per_buffer, 620 struct audioformat *fmt, 621 struct snd_usb_endpoint *sync_ep) 622 { 623 unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb; 624 unsigned int max_packs_per_period, urbs_per_period, urb_packs; 625 unsigned int max_urbs, i; 626 int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels; 627 int tx_length_quirk = (ep->chip->tx_length_quirk && 628 usb_pipeout(ep->pipe)); 629 630 if (pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) { 631 /* 632 * When operating in DSD DOP mode, the size of a sample frame 633 * in hardware differs from the actual physical format width 634 * because we need to make room for the DOP markers. 635 */ 636 frame_bits += channels << 3; 637 } 638 639 ep->datainterval = fmt->datainterval; 640 ep->stride = frame_bits >> 3; 641 642 switch (pcm_format) { 643 case SNDRV_PCM_FORMAT_U8: 644 ep->silence_value = 0x80; 645 break; 646 case SNDRV_PCM_FORMAT_DSD_U8: 647 case SNDRV_PCM_FORMAT_DSD_U16_LE: 648 case SNDRV_PCM_FORMAT_DSD_U32_LE: 649 case SNDRV_PCM_FORMAT_DSD_U16_BE: 650 case SNDRV_PCM_FORMAT_DSD_U32_BE: 651 ep->silence_value = 0x69; 652 break; 653 default: 654 ep->silence_value = 0; 655 } 656 657 /* assume max. frequency is 50% higher than nominal */ 658 ep->freqmax = ep->freqn + (ep->freqn >> 1); 659 /* Round up freqmax to nearest integer in order to calculate maximum 660 * packet size, which must represent a whole number of frames. 661 * This is accomplished by adding 0x0.ffff before converting the 662 * Q16.16 format into integer. 663 * In order to accurately calculate the maximum packet size when 664 * the data interval is more than 1 (i.e. ep->datainterval > 0), 665 * multiply by the data interval prior to rounding. For instance, 666 * a freqmax of 41 kHz will result in a max packet size of 6 (5.125) 667 * frames with a data interval of 1, but 11 (10.25) frames with a 668 * data interval of 2. 669 * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the 670 * maximum datainterval value of 3, at USB full speed, higher for 671 * USB high speed, noting that ep->freqmax is in units of 672 * frames per packet in Q16.16 format.) 673 */ 674 maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) * 675 (frame_bits >> 3); 676 if (tx_length_quirk) 677 maxsize += sizeof(__le32); /* Space for length descriptor */ 678 /* but wMaxPacketSize might reduce this */ 679 if (ep->maxpacksize && ep->maxpacksize < maxsize) { 680 /* whatever fits into a max. size packet */ 681 unsigned int data_maxsize = maxsize = ep->maxpacksize; 682 683 if (tx_length_quirk) 684 /* Need to remove the length descriptor to calc freq */ 685 data_maxsize -= sizeof(__le32); 686 ep->freqmax = (data_maxsize / (frame_bits >> 3)) 687 << (16 - ep->datainterval); 688 } 689 690 if (ep->fill_max) 691 ep->curpacksize = ep->maxpacksize; 692 else 693 ep->curpacksize = maxsize; 694 695 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) { 696 packs_per_ms = 8 >> ep->datainterval; 697 max_packs_per_urb = MAX_PACKS_HS; 698 } else { 699 packs_per_ms = 1; 700 max_packs_per_urb = MAX_PACKS; 701 } 702 if (sync_ep && !snd_usb_endpoint_implicit_feedback_sink(ep)) 703 max_packs_per_urb = min(max_packs_per_urb, 704 1U << sync_ep->syncinterval); 705 max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval); 706 707 /* 708 * Capture endpoints need to use small URBs because there's no way 709 * to tell in advance where the next period will end, and we don't 710 * want the next URB to complete much after the period ends. 711 * 712 * Playback endpoints with implicit sync much use the same parameters 713 * as their corresponding capture endpoint. 714 */ 715 if (usb_pipein(ep->pipe) || 716 snd_usb_endpoint_implicit_feedback_sink(ep)) { 717 718 urb_packs = packs_per_ms; 719 /* 720 * Wireless devices can poll at a max rate of once per 4ms. 721 * For dataintervals less than 5, increase the packet count to 722 * allow the host controller to use bursting to fill in the 723 * gaps. 724 */ 725 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_WIRELESS) { 726 int interval = ep->datainterval; 727 while (interval < 5) { 728 urb_packs <<= 1; 729 ++interval; 730 } 731 } 732 /* make capture URBs <= 1 ms and smaller than a period */ 733 urb_packs = min(max_packs_per_urb, urb_packs); 734 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes) 735 urb_packs >>= 1; 736 ep->nurbs = MAX_URBS; 737 738 /* 739 * Playback endpoints without implicit sync are adjusted so that 740 * a period fits as evenly as possible in the smallest number of 741 * URBs. The total number of URBs is adjusted to the size of the 742 * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits. 743 */ 744 } else { 745 /* determine how small a packet can be */ 746 minsize = (ep->freqn >> (16 - ep->datainterval)) * 747 (frame_bits >> 3); 748 /* with sync from device, assume it can be 12% lower */ 749 if (sync_ep) 750 minsize -= minsize >> 3; 751 minsize = max(minsize, 1u); 752 753 /* how many packets will contain an entire ALSA period? */ 754 max_packs_per_period = DIV_ROUND_UP(period_bytes, minsize); 755 756 /* how many URBs will contain a period? */ 757 urbs_per_period = DIV_ROUND_UP(max_packs_per_period, 758 max_packs_per_urb); 759 /* how many packets are needed in each URB? */ 760 urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period); 761 762 /* limit the number of frames in a single URB */ 763 ep->max_urb_frames = DIV_ROUND_UP(frames_per_period, 764 urbs_per_period); 765 766 /* try to use enough URBs to contain an entire ALSA buffer */ 767 max_urbs = min((unsigned) MAX_URBS, 768 MAX_QUEUE * packs_per_ms / urb_packs); 769 ep->nurbs = min(max_urbs, urbs_per_period * periods_per_buffer); 770 } 771 772 /* allocate and initialize data urbs */ 773 for (i = 0; i < ep->nurbs; i++) { 774 struct snd_urb_ctx *u = &ep->urb[i]; 775 u->index = i; 776 u->ep = ep; 777 u->packets = urb_packs; 778 u->buffer_size = maxsize * u->packets; 779 780 if (fmt->fmt_type == UAC_FORMAT_TYPE_II) 781 u->packets++; /* for transfer delimiter */ 782 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL); 783 if (!u->urb) 784 goto out_of_memory; 785 786 u->urb->transfer_buffer = 787 usb_alloc_coherent(ep->chip->dev, u->buffer_size, 788 GFP_KERNEL, &u->urb->transfer_dma); 789 if (!u->urb->transfer_buffer) 790 goto out_of_memory; 791 u->urb->pipe = ep->pipe; 792 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP; 793 u->urb->interval = 1 << ep->datainterval; 794 u->urb->context = u; 795 u->urb->complete = snd_complete_urb; 796 INIT_LIST_HEAD(&u->ready_list); 797 } 798 799 return 0; 800 801 out_of_memory: 802 release_urbs(ep, 0); 803 return -ENOMEM; 804 } 805 806 /* 807 * configure a sync endpoint 808 */ 809 static int sync_ep_set_params(struct snd_usb_endpoint *ep) 810 { 811 int i; 812 813 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4, 814 GFP_KERNEL, &ep->sync_dma); 815 if (!ep->syncbuf) 816 return -ENOMEM; 817 818 for (i = 0; i < SYNC_URBS; i++) { 819 struct snd_urb_ctx *u = &ep->urb[i]; 820 u->index = i; 821 u->ep = ep; 822 u->packets = 1; 823 u->urb = usb_alloc_urb(1, GFP_KERNEL); 824 if (!u->urb) 825 goto out_of_memory; 826 u->urb->transfer_buffer = ep->syncbuf + i * 4; 827 u->urb->transfer_dma = ep->sync_dma + i * 4; 828 u->urb->transfer_buffer_length = 4; 829 u->urb->pipe = ep->pipe; 830 u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP; 831 u->urb->number_of_packets = 1; 832 u->urb->interval = 1 << ep->syncinterval; 833 u->urb->context = u; 834 u->urb->complete = snd_complete_urb; 835 } 836 837 ep->nurbs = SYNC_URBS; 838 839 return 0; 840 841 out_of_memory: 842 release_urbs(ep, 0); 843 return -ENOMEM; 844 } 845 846 /** 847 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint 848 * 849 * @ep: the snd_usb_endpoint to configure 850 * @pcm_format: the audio fomat. 851 * @channels: the number of audio channels. 852 * @period_bytes: the number of bytes in one alsa period. 853 * @period_frames: the number of frames in one alsa period. 854 * @buffer_periods: the number of periods in one alsa buffer. 855 * @rate: the frame rate. 856 * @fmt: the USB audio format information 857 * @sync_ep: the sync endpoint to use, if any 858 * 859 * Determine the number of URBs to be used on this endpoint. 860 * An endpoint must be configured before it can be started. 861 * An endpoint that is already running can not be reconfigured. 862 */ 863 int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep, 864 snd_pcm_format_t pcm_format, 865 unsigned int channels, 866 unsigned int period_bytes, 867 unsigned int period_frames, 868 unsigned int buffer_periods, 869 unsigned int rate, 870 struct audioformat *fmt, 871 struct snd_usb_endpoint *sync_ep) 872 { 873 int err; 874 875 if (ep->use_count != 0) { 876 usb_audio_warn(ep->chip, 877 "Unable to change format on ep #%x: already in use\n", 878 ep->ep_num); 879 return -EBUSY; 880 } 881 882 /* release old buffers, if any */ 883 release_urbs(ep, 0); 884 885 ep->datainterval = fmt->datainterval; 886 ep->maxpacksize = fmt->maxpacksize; 887 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX); 888 889 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL) 890 ep->freqn = get_usb_full_speed_rate(rate); 891 else 892 ep->freqn = get_usb_high_speed_rate(rate); 893 894 /* calculate the frequency in 16.16 format */ 895 ep->freqm = ep->freqn; 896 ep->freqshift = INT_MIN; 897 898 ep->phase = 0; 899 900 switch (ep->type) { 901 case SND_USB_ENDPOINT_TYPE_DATA: 902 err = data_ep_set_params(ep, pcm_format, channels, 903 period_bytes, period_frames, 904 buffer_periods, fmt, sync_ep); 905 break; 906 case SND_USB_ENDPOINT_TYPE_SYNC: 907 err = sync_ep_set_params(ep); 908 break; 909 default: 910 err = -EINVAL; 911 } 912 913 usb_audio_dbg(ep->chip, 914 "Setting params for ep #%x (type %d, %d urbs), ret=%d\n", 915 ep->ep_num, ep->type, ep->nurbs, err); 916 917 return err; 918 } 919 920 /** 921 * snd_usb_endpoint_start: start an snd_usb_endpoint 922 * 923 * @ep: the endpoint to start 924 * 925 * A call to this function will increment the use count of the endpoint. 926 * In case it is not already running, the URBs for this endpoint will be 927 * submitted. Otherwise, this function does nothing. 928 * 929 * Must be balanced to calls of snd_usb_endpoint_stop(). 930 * 931 * Returns an error if the URB submission failed, 0 in all other cases. 932 */ 933 int snd_usb_endpoint_start(struct snd_usb_endpoint *ep) 934 { 935 int err; 936 unsigned int i; 937 938 if (atomic_read(&ep->chip->shutdown)) 939 return -EBADFD; 940 941 /* already running? */ 942 if (++ep->use_count != 1) 943 return 0; 944 945 /* just to be sure */ 946 deactivate_urbs(ep, false); 947 948 ep->active_mask = 0; 949 ep->unlink_mask = 0; 950 ep->phase = 0; 951 952 snd_usb_endpoint_start_quirk(ep); 953 954 /* 955 * If this endpoint has a data endpoint as implicit feedback source, 956 * don't start the urbs here. Instead, mark them all as available, 957 * wait for the record urbs to return and queue the playback urbs 958 * from that context. 959 */ 960 961 set_bit(EP_FLAG_RUNNING, &ep->flags); 962 963 if (snd_usb_endpoint_implicit_feedback_sink(ep)) { 964 for (i = 0; i < ep->nurbs; i++) { 965 struct snd_urb_ctx *ctx = ep->urb + i; 966 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs); 967 } 968 969 return 0; 970 } 971 972 for (i = 0; i < ep->nurbs; i++) { 973 struct urb *urb = ep->urb[i].urb; 974 975 if (snd_BUG_ON(!urb)) 976 goto __error; 977 978 if (usb_pipeout(ep->pipe)) { 979 prepare_outbound_urb(ep, urb->context); 980 } else { 981 prepare_inbound_urb(ep, urb->context); 982 } 983 984 err = usb_submit_urb(urb, GFP_ATOMIC); 985 if (err < 0) { 986 usb_audio_err(ep->chip, 987 "cannot submit urb %d, error %d: %s\n", 988 i, err, usb_error_string(err)); 989 goto __error; 990 } 991 set_bit(i, &ep->active_mask); 992 } 993 994 return 0; 995 996 __error: 997 clear_bit(EP_FLAG_RUNNING, &ep->flags); 998 ep->use_count--; 999 deactivate_urbs(ep, false); 1000 return -EPIPE; 1001 } 1002 1003 /** 1004 * snd_usb_endpoint_stop: stop an snd_usb_endpoint 1005 * 1006 * @ep: the endpoint to stop (may be NULL) 1007 * 1008 * A call to this function will decrement the use count of the endpoint. 1009 * In case the last user has requested the endpoint stop, the URBs will 1010 * actually be deactivated. 1011 * 1012 * Must be balanced to calls of snd_usb_endpoint_start(). 1013 * 1014 * The caller needs to synchronize the pending stop operation via 1015 * snd_usb_endpoint_sync_pending_stop(). 1016 */ 1017 void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep) 1018 { 1019 if (!ep) 1020 return; 1021 1022 if (snd_BUG_ON(ep->use_count == 0)) 1023 return; 1024 1025 if (--ep->use_count == 0) { 1026 deactivate_urbs(ep, false); 1027 set_bit(EP_FLAG_STOPPING, &ep->flags); 1028 } 1029 } 1030 1031 /** 1032 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint 1033 * 1034 * @ep: the endpoint to deactivate 1035 * 1036 * If the endpoint is not currently in use, this functions will 1037 * deactivate its associated URBs. 1038 * 1039 * In case of any active users, this functions does nothing. 1040 */ 1041 void snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep) 1042 { 1043 if (!ep) 1044 return; 1045 1046 if (ep->use_count != 0) 1047 return; 1048 1049 deactivate_urbs(ep, true); 1050 wait_clear_urbs(ep); 1051 } 1052 1053 /** 1054 * snd_usb_endpoint_release: Tear down an snd_usb_endpoint 1055 * 1056 * @ep: the endpoint to release 1057 * 1058 * This function does not care for the endpoint's use count but will tear 1059 * down all the streaming URBs immediately. 1060 */ 1061 void snd_usb_endpoint_release(struct snd_usb_endpoint *ep) 1062 { 1063 release_urbs(ep, 1); 1064 } 1065 1066 /** 1067 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint 1068 * 1069 * @ep: the endpoint to free 1070 * 1071 * This free all resources of the given ep. 1072 */ 1073 void snd_usb_endpoint_free(struct snd_usb_endpoint *ep) 1074 { 1075 kfree(ep); 1076 } 1077 1078 /** 1079 * snd_usb_handle_sync_urb: parse an USB sync packet 1080 * 1081 * @ep: the endpoint to handle the packet 1082 * @sender: the sending endpoint 1083 * @urb: the received packet 1084 * 1085 * This function is called from the context of an endpoint that received 1086 * the packet and is used to let another endpoint object handle the payload. 1087 */ 1088 void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep, 1089 struct snd_usb_endpoint *sender, 1090 const struct urb *urb) 1091 { 1092 int shift; 1093 unsigned int f; 1094 unsigned long flags; 1095 1096 snd_BUG_ON(ep == sender); 1097 1098 /* 1099 * In case the endpoint is operating in implicit feedback mode, prepare 1100 * a new outbound URB that has the same layout as the received packet 1101 * and add it to the list of pending urbs. queue_pending_output_urbs() 1102 * will take care of them later. 1103 */ 1104 if (snd_usb_endpoint_implicit_feedback_sink(ep) && 1105 ep->use_count != 0) { 1106 1107 /* implicit feedback case */ 1108 int i, bytes = 0; 1109 struct snd_urb_ctx *in_ctx; 1110 struct snd_usb_packet_info *out_packet; 1111 1112 in_ctx = urb->context; 1113 1114 /* Count overall packet size */ 1115 for (i = 0; i < in_ctx->packets; i++) 1116 if (urb->iso_frame_desc[i].status == 0) 1117 bytes += urb->iso_frame_desc[i].actual_length; 1118 1119 /* 1120 * skip empty packets. At least M-Audio's Fast Track Ultra stops 1121 * streaming once it received a 0-byte OUT URB 1122 */ 1123 if (bytes == 0) 1124 return; 1125 1126 spin_lock_irqsave(&ep->lock, flags); 1127 out_packet = ep->next_packet + ep->next_packet_write_pos; 1128 1129 /* 1130 * Iterate through the inbound packet and prepare the lengths 1131 * for the output packet. The OUT packet we are about to send 1132 * will have the same amount of payload bytes per stride as the 1133 * IN packet we just received. Since the actual size is scaled 1134 * by the stride, use the sender stride to calculate the length 1135 * in case the number of channels differ between the implicitly 1136 * fed-back endpoint and the synchronizing endpoint. 1137 */ 1138 1139 out_packet->packets = in_ctx->packets; 1140 for (i = 0; i < in_ctx->packets; i++) { 1141 if (urb->iso_frame_desc[i].status == 0) 1142 out_packet->packet_size[i] = 1143 urb->iso_frame_desc[i].actual_length / sender->stride; 1144 else 1145 out_packet->packet_size[i] = 0; 1146 } 1147 1148 ep->next_packet_write_pos++; 1149 ep->next_packet_write_pos %= MAX_URBS; 1150 spin_unlock_irqrestore(&ep->lock, flags); 1151 queue_pending_output_urbs(ep); 1152 1153 return; 1154 } 1155 1156 /* 1157 * process after playback sync complete 1158 * 1159 * Full speed devices report feedback values in 10.14 format as samples 1160 * per frame, high speed devices in 16.16 format as samples per 1161 * microframe. 1162 * 1163 * Because the Audio Class 1 spec was written before USB 2.0, many high 1164 * speed devices use a wrong interpretation, some others use an 1165 * entirely different format. 1166 * 1167 * Therefore, we cannot predict what format any particular device uses 1168 * and must detect it automatically. 1169 */ 1170 1171 if (urb->iso_frame_desc[0].status != 0 || 1172 urb->iso_frame_desc[0].actual_length < 3) 1173 return; 1174 1175 f = le32_to_cpup(urb->transfer_buffer); 1176 if (urb->iso_frame_desc[0].actual_length == 3) 1177 f &= 0x00ffffff; 1178 else 1179 f &= 0x0fffffff; 1180 1181 if (f == 0) 1182 return; 1183 1184 if (unlikely(sender->tenor_fb_quirk)) { 1185 /* 1186 * Devices based on Tenor 8802 chipsets (TEAC UD-H01 1187 * and others) sometimes change the feedback value 1188 * by +/- 0x1.0000. 1189 */ 1190 if (f < ep->freqn - 0x8000) 1191 f += 0xf000; 1192 else if (f > ep->freqn + 0x8000) 1193 f -= 0xf000; 1194 } else if (unlikely(ep->freqshift == INT_MIN)) { 1195 /* 1196 * The first time we see a feedback value, determine its format 1197 * by shifting it left or right until it matches the nominal 1198 * frequency value. This assumes that the feedback does not 1199 * differ from the nominal value more than +50% or -25%. 1200 */ 1201 shift = 0; 1202 while (f < ep->freqn - ep->freqn / 4) { 1203 f <<= 1; 1204 shift++; 1205 } 1206 while (f > ep->freqn + ep->freqn / 2) { 1207 f >>= 1; 1208 shift--; 1209 } 1210 ep->freqshift = shift; 1211 } else if (ep->freqshift >= 0) 1212 f <<= ep->freqshift; 1213 else 1214 f >>= -ep->freqshift; 1215 1216 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) { 1217 /* 1218 * If the frequency looks valid, set it. 1219 * This value is referred to in prepare_playback_urb(). 1220 */ 1221 spin_lock_irqsave(&ep->lock, flags); 1222 ep->freqm = f; 1223 spin_unlock_irqrestore(&ep->lock, flags); 1224 } else { 1225 /* 1226 * Out of range; maybe the shift value is wrong. 1227 * Reset it so that we autodetect again the next time. 1228 */ 1229 ep->freqshift = INT_MIN; 1230 } 1231 } 1232 1233