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_ACTIVATED 0 37 #define EP_FLAG_RUNNING 1 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_implict_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 /* 187 * Prepare a PLAYBACK urb for submission to the bus. 188 */ 189 static void prepare_outbound_urb(struct snd_usb_endpoint *ep, 190 struct snd_urb_ctx *ctx) 191 { 192 int i; 193 struct urb *urb = ctx->urb; 194 unsigned char *cp = urb->transfer_buffer; 195 196 urb->dev = ep->chip->dev; /* we need to set this at each time */ 197 198 switch (ep->type) { 199 case SND_USB_ENDPOINT_TYPE_DATA: 200 if (ep->prepare_data_urb) { 201 ep->prepare_data_urb(ep->data_subs, urb); 202 } else { 203 /* no data provider, so send silence */ 204 unsigned int offs = 0; 205 for (i = 0; i < ctx->packets; ++i) { 206 int counts; 207 208 if (ctx->packet_size[i]) 209 counts = ctx->packet_size[i]; 210 else 211 counts = snd_usb_endpoint_next_packet_size(ep); 212 213 urb->iso_frame_desc[i].offset = offs * ep->stride; 214 urb->iso_frame_desc[i].length = counts * ep->stride; 215 offs += counts; 216 } 217 218 urb->number_of_packets = ctx->packets; 219 urb->transfer_buffer_length = offs * ep->stride; 220 memset(urb->transfer_buffer, ep->silence_value, 221 offs * ep->stride); 222 } 223 break; 224 225 case SND_USB_ENDPOINT_TYPE_SYNC: 226 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) { 227 /* 228 * fill the length and offset of each urb descriptor. 229 * the fixed 12.13 frequency is passed as 16.16 through the pipe. 230 */ 231 urb->iso_frame_desc[0].length = 4; 232 urb->iso_frame_desc[0].offset = 0; 233 cp[0] = ep->freqn; 234 cp[1] = ep->freqn >> 8; 235 cp[2] = ep->freqn >> 16; 236 cp[3] = ep->freqn >> 24; 237 } else { 238 /* 239 * fill the length and offset of each urb descriptor. 240 * the fixed 10.14 frequency is passed through the pipe. 241 */ 242 urb->iso_frame_desc[0].length = 3; 243 urb->iso_frame_desc[0].offset = 0; 244 cp[0] = ep->freqn >> 2; 245 cp[1] = ep->freqn >> 10; 246 cp[2] = ep->freqn >> 18; 247 } 248 249 break; 250 } 251 } 252 253 /* 254 * Prepare a CAPTURE or SYNC urb for submission to the bus. 255 */ 256 static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep, 257 struct snd_urb_ctx *urb_ctx) 258 { 259 int i, offs; 260 struct urb *urb = urb_ctx->urb; 261 262 urb->dev = ep->chip->dev; /* we need to set this at each time */ 263 264 switch (ep->type) { 265 case SND_USB_ENDPOINT_TYPE_DATA: 266 offs = 0; 267 for (i = 0; i < urb_ctx->packets; i++) { 268 urb->iso_frame_desc[i].offset = offs; 269 urb->iso_frame_desc[i].length = ep->curpacksize; 270 offs += ep->curpacksize; 271 } 272 273 urb->transfer_buffer_length = offs; 274 urb->number_of_packets = urb_ctx->packets; 275 break; 276 277 case SND_USB_ENDPOINT_TYPE_SYNC: 278 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize); 279 urb->iso_frame_desc[0].offset = 0; 280 break; 281 } 282 } 283 284 /* 285 * Send output urbs that have been prepared previously. URBs are dequeued 286 * from ep->ready_playback_urbs and in case there there aren't any available 287 * or there are no packets that have been prepared, this function does 288 * nothing. 289 * 290 * The reason why the functionality of sending and preparing URBs is separated 291 * is that host controllers don't guarantee the order in which they return 292 * inbound and outbound packets to their submitters. 293 * 294 * This function is only used for implicit feedback endpoints. For endpoints 295 * driven by dedicated sync endpoints, URBs are immediately re-submitted 296 * from their completion handler. 297 */ 298 static void queue_pending_output_urbs(struct snd_usb_endpoint *ep) 299 { 300 while (test_bit(EP_FLAG_RUNNING, &ep->flags)) { 301 302 unsigned long flags; 303 struct snd_usb_packet_info *uninitialized_var(packet); 304 struct snd_urb_ctx *ctx = NULL; 305 struct urb *urb; 306 int err, i; 307 308 spin_lock_irqsave(&ep->lock, flags); 309 if (ep->next_packet_read_pos != ep->next_packet_write_pos) { 310 packet = ep->next_packet + ep->next_packet_read_pos; 311 ep->next_packet_read_pos++; 312 ep->next_packet_read_pos %= MAX_URBS; 313 314 /* take URB out of FIFO */ 315 if (!list_empty(&ep->ready_playback_urbs)) 316 ctx = list_first_entry(&ep->ready_playback_urbs, 317 struct snd_urb_ctx, ready_list); 318 } 319 spin_unlock_irqrestore(&ep->lock, flags); 320 321 if (ctx == NULL) 322 return; 323 324 list_del_init(&ctx->ready_list); 325 urb = ctx->urb; 326 327 /* copy over the length information */ 328 for (i = 0; i < packet->packets; i++) 329 ctx->packet_size[i] = packet->packet_size[i]; 330 331 /* call the data handler to fill in playback data */ 332 prepare_outbound_urb(ep, ctx); 333 334 err = usb_submit_urb(ctx->urb, GFP_ATOMIC); 335 if (err < 0) 336 snd_printk(KERN_ERR "Unable to submit urb #%d: %d (urb %p)\n", 337 ctx->index, err, ctx->urb); 338 else 339 set_bit(ctx->index, &ep->active_mask); 340 } 341 } 342 343 /* 344 * complete callback for urbs 345 */ 346 static void snd_complete_urb(struct urb *urb) 347 { 348 struct snd_urb_ctx *ctx = urb->context; 349 struct snd_usb_endpoint *ep = ctx->ep; 350 int err; 351 352 if (unlikely(urb->status == -ENOENT || /* unlinked */ 353 urb->status == -ENODEV || /* device removed */ 354 urb->status == -ECONNRESET || /* unlinked */ 355 urb->status == -ESHUTDOWN || /* device disabled */ 356 ep->chip->shutdown)) /* device disconnected */ 357 goto exit_clear; 358 359 if (usb_pipeout(ep->pipe)) { 360 retire_outbound_urb(ep, ctx); 361 /* can be stopped during retire callback */ 362 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags))) 363 goto exit_clear; 364 365 if (snd_usb_endpoint_implict_feedback_sink(ep)) { 366 unsigned long flags; 367 368 spin_lock_irqsave(&ep->lock, flags); 369 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs); 370 spin_unlock_irqrestore(&ep->lock, flags); 371 queue_pending_output_urbs(ep); 372 373 goto exit_clear; 374 } 375 376 prepare_outbound_urb(ep, ctx); 377 } else { 378 retire_inbound_urb(ep, ctx); 379 /* can be stopped during retire callback */ 380 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags))) 381 goto exit_clear; 382 383 prepare_inbound_urb(ep, ctx); 384 } 385 386 err = usb_submit_urb(urb, GFP_ATOMIC); 387 if (err == 0) 388 return; 389 390 snd_printk(KERN_ERR "cannot submit urb (err = %d)\n", err); 391 //snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN); 392 393 exit_clear: 394 clear_bit(ctx->index, &ep->active_mask); 395 } 396 397 /** 398 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip 399 * 400 * @chip: The chip 401 * @alts: The USB host interface 402 * @ep_num: The number of the endpoint to use 403 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE 404 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC 405 * 406 * If the requested endpoint has not been added to the given chip before, 407 * a new instance is created. Otherwise, a pointer to the previoulsy 408 * created instance is returned. In case of any error, NULL is returned. 409 * 410 * New endpoints will be added to chip->ep_list and must be freed by 411 * calling snd_usb_endpoint_free(). 412 */ 413 struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip, 414 struct usb_host_interface *alts, 415 int ep_num, int direction, int type) 416 { 417 struct list_head *p; 418 struct snd_usb_endpoint *ep; 419 int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK; 420 421 mutex_lock(&chip->mutex); 422 423 list_for_each(p, &chip->ep_list) { 424 ep = list_entry(p, struct snd_usb_endpoint, list); 425 if (ep->ep_num == ep_num && 426 ep->iface == alts->desc.bInterfaceNumber && 427 ep->alt_idx == alts->desc.bAlternateSetting) { 428 snd_printdd(KERN_DEBUG "Re-using EP %x in iface %d,%d @%p\n", 429 ep_num, ep->iface, ep->alt_idx, ep); 430 goto __exit_unlock; 431 } 432 } 433 434 snd_printdd(KERN_DEBUG "Creating new %s %s endpoint #%x\n", 435 is_playback ? "playback" : "capture", 436 type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync", 437 ep_num); 438 439 ep = kzalloc(sizeof(*ep), GFP_KERNEL); 440 if (!ep) 441 goto __exit_unlock; 442 443 ep->chip = chip; 444 spin_lock_init(&ep->lock); 445 ep->type = type; 446 ep->ep_num = ep_num; 447 ep->iface = alts->desc.bInterfaceNumber; 448 ep->alt_idx = alts->desc.bAlternateSetting; 449 INIT_LIST_HEAD(&ep->ready_playback_urbs); 450 ep_num &= USB_ENDPOINT_NUMBER_MASK; 451 452 if (is_playback) 453 ep->pipe = usb_sndisocpipe(chip->dev, ep_num); 454 else 455 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num); 456 457 if (type == SND_USB_ENDPOINT_TYPE_SYNC) { 458 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE && 459 get_endpoint(alts, 1)->bRefresh >= 1 && 460 get_endpoint(alts, 1)->bRefresh <= 9) 461 ep->syncinterval = get_endpoint(alts, 1)->bRefresh; 462 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) 463 ep->syncinterval = 1; 464 else if (get_endpoint(alts, 1)->bInterval >= 1 && 465 get_endpoint(alts, 1)->bInterval <= 16) 466 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1; 467 else 468 ep->syncinterval = 3; 469 470 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize); 471 } 472 473 list_add_tail(&ep->list, &chip->ep_list); 474 475 __exit_unlock: 476 mutex_unlock(&chip->mutex); 477 478 return ep; 479 } 480 481 /* 482 * wait until all urbs are processed. 483 */ 484 static int wait_clear_urbs(struct snd_usb_endpoint *ep) 485 { 486 unsigned long end_time = jiffies + msecs_to_jiffies(1000); 487 unsigned int i; 488 int alive; 489 490 do { 491 alive = 0; 492 for (i = 0; i < ep->nurbs; i++) 493 if (test_bit(i, &ep->active_mask)) 494 alive++; 495 496 if (!alive) 497 break; 498 499 schedule_timeout_uninterruptible(1); 500 } while (time_before(jiffies, end_time)); 501 502 if (alive) 503 snd_printk(KERN_ERR "timeout: still %d active urbs on EP #%x\n", 504 alive, ep->ep_num); 505 506 return 0; 507 } 508 509 /* 510 * unlink active urbs. 511 */ 512 static int deactivate_urbs(struct snd_usb_endpoint *ep, int force, int can_sleep) 513 { 514 unsigned int i; 515 int async; 516 517 if (!force && ep->chip->shutdown) /* to be sure... */ 518 return -EBADFD; 519 520 async = !can_sleep && ep->chip->async_unlink; 521 522 clear_bit(EP_FLAG_RUNNING, &ep->flags); 523 524 INIT_LIST_HEAD(&ep->ready_playback_urbs); 525 ep->next_packet_read_pos = 0; 526 ep->next_packet_write_pos = 0; 527 528 if (!async && in_interrupt()) 529 return 0; 530 531 for (i = 0; i < ep->nurbs; i++) { 532 if (test_bit(i, &ep->active_mask)) { 533 if (!test_and_set_bit(i, &ep->unlink_mask)) { 534 struct urb *u = ep->urb[i].urb; 535 if (async) 536 usb_unlink_urb(u); 537 else 538 usb_kill_urb(u); 539 } 540 } 541 } 542 543 return 0; 544 } 545 546 /* 547 * release an endpoint's urbs 548 */ 549 static void release_urbs(struct snd_usb_endpoint *ep, int force) 550 { 551 int i; 552 553 /* route incoming urbs to nirvana */ 554 ep->retire_data_urb = NULL; 555 ep->prepare_data_urb = NULL; 556 557 /* stop urbs */ 558 deactivate_urbs(ep, force, 1); 559 wait_clear_urbs(ep); 560 561 for (i = 0; i < ep->nurbs; i++) 562 release_urb_ctx(&ep->urb[i]); 563 564 if (ep->syncbuf) 565 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4, 566 ep->syncbuf, ep->sync_dma); 567 568 ep->syncbuf = NULL; 569 ep->nurbs = 0; 570 } 571 572 /* 573 * configure a data endpoint 574 */ 575 static int data_ep_set_params(struct snd_usb_endpoint *ep, 576 snd_pcm_format_t pcm_format, 577 unsigned int channels, 578 unsigned int period_bytes, 579 struct audioformat *fmt, 580 struct snd_usb_endpoint *sync_ep) 581 { 582 unsigned int maxsize, i, urb_packs, total_packs, packs_per_ms; 583 int is_playback = usb_pipeout(ep->pipe); 584 int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels; 585 586 ep->datainterval = fmt->datainterval; 587 ep->stride = frame_bits >> 3; 588 ep->silence_value = pcm_format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0; 589 590 /* calculate max. frequency */ 591 if (ep->maxpacksize) { 592 /* whatever fits into a max. size packet */ 593 maxsize = ep->maxpacksize; 594 ep->freqmax = (maxsize / (frame_bits >> 3)) 595 << (16 - ep->datainterval); 596 } else { 597 /* no max. packet size: just take 25% higher than nominal */ 598 ep->freqmax = ep->freqn + (ep->freqn >> 2); 599 maxsize = ((ep->freqmax + 0xffff) * (frame_bits >> 3)) 600 >> (16 - ep->datainterval); 601 } 602 603 if (ep->fill_max) 604 ep->curpacksize = ep->maxpacksize; 605 else 606 ep->curpacksize = maxsize; 607 608 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) 609 packs_per_ms = 8 >> ep->datainterval; 610 else 611 packs_per_ms = 1; 612 613 if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) { 614 urb_packs = max(ep->chip->nrpacks, 1); 615 urb_packs = min(urb_packs, (unsigned int) MAX_PACKS); 616 } else { 617 urb_packs = 1; 618 } 619 620 urb_packs *= packs_per_ms; 621 622 if (sync_ep && !snd_usb_endpoint_implict_feedback_sink(ep)) 623 urb_packs = min(urb_packs, 1U << sync_ep->syncinterval); 624 625 /* decide how many packets to be used */ 626 if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) { 627 unsigned int minsize, maxpacks; 628 /* determine how small a packet can be */ 629 minsize = (ep->freqn >> (16 - ep->datainterval)) 630 * (frame_bits >> 3); 631 /* with sync from device, assume it can be 12% lower */ 632 if (sync_ep) 633 minsize -= minsize >> 3; 634 minsize = max(minsize, 1u); 635 total_packs = (period_bytes + minsize - 1) / minsize; 636 /* we need at least two URBs for queueing */ 637 if (total_packs < 2) { 638 total_packs = 2; 639 } else { 640 /* and we don't want too long a queue either */ 641 maxpacks = max(MAX_QUEUE * packs_per_ms, urb_packs * 2); 642 total_packs = min(total_packs, maxpacks); 643 } 644 } else { 645 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes) 646 urb_packs >>= 1; 647 total_packs = MAX_URBS * urb_packs; 648 } 649 650 ep->nurbs = (total_packs + urb_packs - 1) / urb_packs; 651 if (ep->nurbs > MAX_URBS) { 652 /* too much... */ 653 ep->nurbs = MAX_URBS; 654 total_packs = MAX_URBS * urb_packs; 655 } else if (ep->nurbs < 2) { 656 /* too little - we need at least two packets 657 * to ensure contiguous playback/capture 658 */ 659 ep->nurbs = 2; 660 } 661 662 /* allocate and initialize data urbs */ 663 for (i = 0; i < ep->nurbs; i++) { 664 struct snd_urb_ctx *u = &ep->urb[i]; 665 u->index = i; 666 u->ep = ep; 667 u->packets = (i + 1) * total_packs / ep->nurbs 668 - i * total_packs / ep->nurbs; 669 u->buffer_size = maxsize * u->packets; 670 671 if (fmt->fmt_type == UAC_FORMAT_TYPE_II) 672 u->packets++; /* for transfer delimiter */ 673 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL); 674 if (!u->urb) 675 goto out_of_memory; 676 677 u->urb->transfer_buffer = 678 usb_alloc_coherent(ep->chip->dev, u->buffer_size, 679 GFP_KERNEL, &u->urb->transfer_dma); 680 if (!u->urb->transfer_buffer) 681 goto out_of_memory; 682 u->urb->pipe = ep->pipe; 683 u->urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; 684 u->urb->interval = 1 << ep->datainterval; 685 u->urb->context = u; 686 u->urb->complete = snd_complete_urb; 687 INIT_LIST_HEAD(&u->ready_list); 688 } 689 690 return 0; 691 692 out_of_memory: 693 release_urbs(ep, 0); 694 return -ENOMEM; 695 } 696 697 /* 698 * configure a sync endpoint 699 */ 700 static int sync_ep_set_params(struct snd_usb_endpoint *ep, 701 struct audioformat *fmt) 702 { 703 int i; 704 705 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4, 706 GFP_KERNEL, &ep->sync_dma); 707 if (!ep->syncbuf) 708 return -ENOMEM; 709 710 for (i = 0; i < SYNC_URBS; i++) { 711 struct snd_urb_ctx *u = &ep->urb[i]; 712 u->index = i; 713 u->ep = ep; 714 u->packets = 1; 715 u->urb = usb_alloc_urb(1, GFP_KERNEL); 716 if (!u->urb) 717 goto out_of_memory; 718 u->urb->transfer_buffer = ep->syncbuf + i * 4; 719 u->urb->transfer_dma = ep->sync_dma + i * 4; 720 u->urb->transfer_buffer_length = 4; 721 u->urb->pipe = ep->pipe; 722 u->urb->transfer_flags = URB_ISO_ASAP | 723 URB_NO_TRANSFER_DMA_MAP; 724 u->urb->number_of_packets = 1; 725 u->urb->interval = 1 << ep->syncinterval; 726 u->urb->context = u; 727 u->urb->complete = snd_complete_urb; 728 } 729 730 ep->nurbs = SYNC_URBS; 731 732 return 0; 733 734 out_of_memory: 735 release_urbs(ep, 0); 736 return -ENOMEM; 737 } 738 739 /** 740 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint 741 * 742 * @ep: the snd_usb_endpoint to configure 743 * @pcm_format: the audio fomat. 744 * @channels: the number of audio channels. 745 * @period_bytes: the number of bytes in one alsa period. 746 * @rate: the frame rate. 747 * @fmt: the USB audio format information 748 * @sync_ep: the sync endpoint to use, if any 749 * 750 * Determine the number of URBs to be used on this endpoint. 751 * An endpoint must be configured before it can be started. 752 * An endpoint that is already running can not be reconfigured. 753 */ 754 int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep, 755 snd_pcm_format_t pcm_format, 756 unsigned int channels, 757 unsigned int period_bytes, 758 unsigned int rate, 759 struct audioformat *fmt, 760 struct snd_usb_endpoint *sync_ep) 761 { 762 int err; 763 764 if (ep->use_count != 0) { 765 snd_printk(KERN_WARNING "Unable to change format on ep #%x: already in use\n", 766 ep->ep_num); 767 return -EBUSY; 768 } 769 770 /* release old buffers, if any */ 771 release_urbs(ep, 0); 772 773 ep->datainterval = fmt->datainterval; 774 ep->maxpacksize = fmt->maxpacksize; 775 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX); 776 777 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL) 778 ep->freqn = get_usb_full_speed_rate(rate); 779 else 780 ep->freqn = get_usb_high_speed_rate(rate); 781 782 /* calculate the frequency in 16.16 format */ 783 ep->freqm = ep->freqn; 784 ep->freqshift = INT_MIN; 785 786 ep->phase = 0; 787 788 switch (ep->type) { 789 case SND_USB_ENDPOINT_TYPE_DATA: 790 err = data_ep_set_params(ep, pcm_format, channels, 791 period_bytes, fmt, sync_ep); 792 break; 793 case SND_USB_ENDPOINT_TYPE_SYNC: 794 err = sync_ep_set_params(ep, fmt); 795 break; 796 default: 797 err = -EINVAL; 798 } 799 800 snd_printdd(KERN_DEBUG "Setting params for ep #%x (type %d, %d urbs), ret=%d\n", 801 ep->ep_num, ep->type, ep->nurbs, err); 802 803 return err; 804 } 805 806 /** 807 * snd_usb_endpoint_start: start an snd_usb_endpoint 808 * 809 * @ep: the endpoint to start 810 * @can_sleep: flag indicating whether the operation is executed in 811 * non-atomic context 812 * 813 * A call to this function will increment the use count of the endpoint. 814 * In case it is not already running, the URBs for this endpoint will be 815 * submitted. Otherwise, this function does nothing. 816 * 817 * Must be balanced to calls of snd_usb_endpoint_stop(). 818 * 819 * Returns an error if the URB submission failed, 0 in all other cases. 820 */ 821 int snd_usb_endpoint_start(struct snd_usb_endpoint *ep, int can_sleep) 822 { 823 int err; 824 unsigned int i; 825 826 if (ep->chip->shutdown) 827 return -EBADFD; 828 829 /* already running? */ 830 if (++ep->use_count != 1) 831 return 0; 832 833 /* just to be sure */ 834 deactivate_urbs(ep, 0, can_sleep); 835 if (can_sleep) 836 wait_clear_urbs(ep); 837 838 ep->active_mask = 0; 839 ep->unlink_mask = 0; 840 ep->phase = 0; 841 842 snd_usb_endpoint_start_quirk(ep); 843 844 /* 845 * If this endpoint has a data endpoint as implicit feedback source, 846 * don't start the urbs here. Instead, mark them all as available, 847 * wait for the record urbs to return and queue the playback urbs 848 * from that context. 849 */ 850 851 set_bit(EP_FLAG_RUNNING, &ep->flags); 852 853 if (snd_usb_endpoint_implict_feedback_sink(ep)) { 854 for (i = 0; i < ep->nurbs; i++) { 855 struct snd_urb_ctx *ctx = ep->urb + i; 856 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs); 857 } 858 859 return 0; 860 } 861 862 for (i = 0; i < ep->nurbs; i++) { 863 struct urb *urb = ep->urb[i].urb; 864 865 if (snd_BUG_ON(!urb)) 866 goto __error; 867 868 if (usb_pipeout(ep->pipe)) { 869 prepare_outbound_urb(ep, urb->context); 870 } else { 871 prepare_inbound_urb(ep, urb->context); 872 } 873 874 err = usb_submit_urb(urb, GFP_ATOMIC); 875 if (err < 0) { 876 snd_printk(KERN_ERR "cannot submit urb %d, error %d: %s\n", 877 i, err, usb_error_string(err)); 878 goto __error; 879 } 880 set_bit(i, &ep->active_mask); 881 } 882 883 return 0; 884 885 __error: 886 clear_bit(EP_FLAG_RUNNING, &ep->flags); 887 ep->use_count--; 888 deactivate_urbs(ep, 0, 0); 889 return -EPIPE; 890 } 891 892 /** 893 * snd_usb_endpoint_stop: stop an snd_usb_endpoint 894 * 895 * @ep: the endpoint to stop (may be NULL) 896 * 897 * A call to this function will decrement the use count of the endpoint. 898 * In case the last user has requested the endpoint stop, the URBs will 899 * actually be deactivated. 900 * 901 * Must be balanced to calls of snd_usb_endpoint_start(). 902 */ 903 void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep, 904 int force, int can_sleep, int wait) 905 { 906 if (!ep) 907 return; 908 909 if (snd_BUG_ON(ep->use_count == 0)) 910 return; 911 912 if (--ep->use_count == 0) { 913 deactivate_urbs(ep, force, can_sleep); 914 ep->data_subs = NULL; 915 ep->sync_slave = NULL; 916 ep->retire_data_urb = NULL; 917 ep->prepare_data_urb = NULL; 918 919 if (wait) 920 wait_clear_urbs(ep); 921 } 922 } 923 924 /** 925 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint 926 * 927 * @ep: the endpoint to deactivate 928 * 929 * If the endpoint is not currently in use, this functions will select the 930 * alternate interface setting 0 for the interface of this endpoint. 931 * 932 * In case of any active users, this functions does nothing. 933 * 934 * Returns an error if usb_set_interface() failed, 0 in all other 935 * cases. 936 */ 937 int snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep) 938 { 939 if (!ep) 940 return -EINVAL; 941 942 deactivate_urbs(ep, 1, 1); 943 wait_clear_urbs(ep); 944 945 if (ep->use_count != 0) 946 return 0; 947 948 clear_bit(EP_FLAG_ACTIVATED, &ep->flags); 949 950 return 0; 951 } 952 953 /** 954 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint 955 * 956 * @ep: the list header of the endpoint to free 957 * 958 * This function does not care for the endpoint's use count but will tear 959 * down all the streaming URBs immediately and free all resources. 960 */ 961 void snd_usb_endpoint_free(struct list_head *head) 962 { 963 struct snd_usb_endpoint *ep; 964 965 ep = list_entry(head, struct snd_usb_endpoint, list); 966 release_urbs(ep, 1); 967 kfree(ep); 968 } 969 970 /** 971 * snd_usb_handle_sync_urb: parse an USB sync packet 972 * 973 * @ep: the endpoint to handle the packet 974 * @sender: the sending endpoint 975 * @urb: the received packet 976 * 977 * This function is called from the context of an endpoint that received 978 * the packet and is used to let another endpoint object handle the payload. 979 */ 980 void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep, 981 struct snd_usb_endpoint *sender, 982 const struct urb *urb) 983 { 984 int shift; 985 unsigned int f; 986 unsigned long flags; 987 988 snd_BUG_ON(ep == sender); 989 990 /* 991 * In case the endpoint is operating in implicit feedback mode, prepare 992 * a new outbound URB that has the same layout as the received packet 993 * and add it to the list of pending urbs. queue_pending_output_urbs() 994 * will take care of them later. 995 */ 996 if (snd_usb_endpoint_implict_feedback_sink(ep) && 997 ep->use_count != 0) { 998 999 /* implicit feedback case */ 1000 int i, bytes = 0; 1001 struct snd_urb_ctx *in_ctx; 1002 struct snd_usb_packet_info *out_packet; 1003 1004 in_ctx = urb->context; 1005 1006 /* Count overall packet size */ 1007 for (i = 0; i < in_ctx->packets; i++) 1008 if (urb->iso_frame_desc[i].status == 0) 1009 bytes += urb->iso_frame_desc[i].actual_length; 1010 1011 /* 1012 * skip empty packets. At least M-Audio's Fast Track Ultra stops 1013 * streaming once it received a 0-byte OUT URB 1014 */ 1015 if (bytes == 0) 1016 return; 1017 1018 spin_lock_irqsave(&ep->lock, flags); 1019 out_packet = ep->next_packet + ep->next_packet_write_pos; 1020 1021 /* 1022 * Iterate through the inbound packet and prepare the lengths 1023 * for the output packet. The OUT packet we are about to send 1024 * will have the same amount of payload bytes than the IN 1025 * packet we just received. 1026 */ 1027 1028 out_packet->packets = in_ctx->packets; 1029 for (i = 0; i < in_ctx->packets; i++) { 1030 if (urb->iso_frame_desc[i].status == 0) 1031 out_packet->packet_size[i] = 1032 urb->iso_frame_desc[i].actual_length / ep->stride; 1033 else 1034 out_packet->packet_size[i] = 0; 1035 } 1036 1037 ep->next_packet_write_pos++; 1038 ep->next_packet_write_pos %= MAX_URBS; 1039 spin_unlock_irqrestore(&ep->lock, flags); 1040 queue_pending_output_urbs(ep); 1041 1042 return; 1043 } 1044 1045 /* 1046 * process after playback sync complete 1047 * 1048 * Full speed devices report feedback values in 10.14 format as samples 1049 * per frame, high speed devices in 16.16 format as samples per 1050 * microframe. 1051 * 1052 * Because the Audio Class 1 spec was written before USB 2.0, many high 1053 * speed devices use a wrong interpretation, some others use an 1054 * entirely different format. 1055 * 1056 * Therefore, we cannot predict what format any particular device uses 1057 * and must detect it automatically. 1058 */ 1059 1060 if (urb->iso_frame_desc[0].status != 0 || 1061 urb->iso_frame_desc[0].actual_length < 3) 1062 return; 1063 1064 f = le32_to_cpup(urb->transfer_buffer); 1065 if (urb->iso_frame_desc[0].actual_length == 3) 1066 f &= 0x00ffffff; 1067 else 1068 f &= 0x0fffffff; 1069 1070 if (f == 0) 1071 return; 1072 1073 if (unlikely(ep->freqshift == INT_MIN)) { 1074 /* 1075 * The first time we see a feedback value, determine its format 1076 * by shifting it left or right until it matches the nominal 1077 * frequency value. This assumes that the feedback does not 1078 * differ from the nominal value more than +50% or -25%. 1079 */ 1080 shift = 0; 1081 while (f < ep->freqn - ep->freqn / 4) { 1082 f <<= 1; 1083 shift++; 1084 } 1085 while (f > ep->freqn + ep->freqn / 2) { 1086 f >>= 1; 1087 shift--; 1088 } 1089 ep->freqshift = shift; 1090 } else if (ep->freqshift >= 0) 1091 f <<= ep->freqshift; 1092 else 1093 f >>= -ep->freqshift; 1094 1095 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) { 1096 /* 1097 * If the frequency looks valid, set it. 1098 * This value is referred to in prepare_playback_urb(). 1099 */ 1100 spin_lock_irqsave(&ep->lock, flags); 1101 ep->freqm = f; 1102 spin_unlock_irqrestore(&ep->lock, flags); 1103 } else { 1104 /* 1105 * Out of range; maybe the shift value is wrong. 1106 * Reset it so that we autodetect again the next time. 1107 */ 1108 ep->freqshift = INT_MIN; 1109 } 1110 } 1111 1112