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 35 #define EP_FLAG_ACTIVATED 0 36 #define EP_FLAG_RUNNING 1 37 38 /* 39 * snd_usb_endpoint is a model that abstracts everything related to an 40 * USB endpoint and its streaming. 41 * 42 * There are functions to activate and deactivate the streaming URBs and 43 * optional callbacks to let the pcm logic handle the actual content of the 44 * packets for playback and record. Thus, the bus streaming and the audio 45 * handlers are fully decoupled. 46 * 47 * There are two different types of endpoints in audio applications. 48 * 49 * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both 50 * inbound and outbound traffic. 51 * 52 * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and 53 * expect the payload to carry Q10.14 / Q16.16 formatted sync information 54 * (3 or 4 bytes). 55 * 56 * Each endpoint has to be configured prior to being used by calling 57 * snd_usb_endpoint_set_params(). 58 * 59 * The model incorporates a reference counting, so that multiple users 60 * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and 61 * only the first user will effectively start the URBs, and only the last 62 * one to stop it will tear the URBs down again. 63 */ 64 65 /* 66 * convert a sampling rate into our full speed format (fs/1000 in Q16.16) 67 * this will overflow at approx 524 kHz 68 */ 69 static inline unsigned get_usb_full_speed_rate(unsigned int rate) 70 { 71 return ((rate << 13) + 62) / 125; 72 } 73 74 /* 75 * convert a sampling rate into USB high speed format (fs/8000 in Q16.16) 76 * this will overflow at approx 4 MHz 77 */ 78 static inline unsigned get_usb_high_speed_rate(unsigned int rate) 79 { 80 return ((rate << 10) + 62) / 125; 81 } 82 83 /* 84 * release a urb data 85 */ 86 static void release_urb_ctx(struct snd_urb_ctx *u) 87 { 88 if (u->buffer_size) 89 usb_free_coherent(u->ep->chip->dev, u->buffer_size, 90 u->urb->transfer_buffer, 91 u->urb->transfer_dma); 92 usb_free_urb(u->urb); 93 u->urb = NULL; 94 } 95 96 static const char *usb_error_string(int err) 97 { 98 switch (err) { 99 case -ENODEV: 100 return "no device"; 101 case -ENOENT: 102 return "endpoint not enabled"; 103 case -EPIPE: 104 return "endpoint stalled"; 105 case -ENOSPC: 106 return "not enough bandwidth"; 107 case -ESHUTDOWN: 108 return "device disabled"; 109 case -EHOSTUNREACH: 110 return "device suspended"; 111 case -EINVAL: 112 case -EAGAIN: 113 case -EFBIG: 114 case -EMSGSIZE: 115 return "internal error"; 116 default: 117 return "unknown error"; 118 } 119 } 120 121 /** 122 * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type 123 * 124 * @ep: The snd_usb_endpoint 125 * 126 * Determine whether an endpoint is driven by an implicit feedback 127 * data endpoint source. 128 */ 129 int snd_usb_endpoint_implict_feedback_sink(struct snd_usb_endpoint *ep) 130 { 131 return ep->sync_master && 132 ep->sync_master->type == SND_USB_ENDPOINT_TYPE_DATA && 133 ep->type == SND_USB_ENDPOINT_TYPE_DATA && 134 usb_pipeout(ep->pipe); 135 } 136 137 /* 138 * For streaming based on information derived from sync endpoints, 139 * prepare_outbound_urb_sizes() will call next_packet_size() to 140 * determine the number of samples to be sent in the next packet. 141 * 142 * For implicit feedback, next_packet_size() is unused. 143 */ 144 static int next_packet_size(struct snd_usb_endpoint *ep) 145 { 146 unsigned long flags; 147 int ret; 148 149 if (ep->fill_max) 150 return ep->maxframesize; 151 152 spin_lock_irqsave(&ep->lock, flags); 153 ep->phase = (ep->phase & 0xffff) 154 + (ep->freqm << ep->datainterval); 155 ret = min(ep->phase >> 16, ep->maxframesize); 156 spin_unlock_irqrestore(&ep->lock, flags); 157 158 return ret; 159 } 160 161 static void retire_outbound_urb(struct snd_usb_endpoint *ep, 162 struct snd_urb_ctx *urb_ctx) 163 { 164 if (ep->retire_data_urb) 165 ep->retire_data_urb(ep->data_subs, urb_ctx->urb); 166 } 167 168 static void retire_inbound_urb(struct snd_usb_endpoint *ep, 169 struct snd_urb_ctx *urb_ctx) 170 { 171 struct urb *urb = urb_ctx->urb; 172 173 if (ep->sync_slave) 174 snd_usb_handle_sync_urb(ep->sync_slave, ep, urb); 175 176 if (ep->retire_data_urb) 177 ep->retire_data_urb(ep->data_subs, urb); 178 } 179 180 static void prepare_outbound_urb_sizes(struct snd_usb_endpoint *ep, 181 struct snd_urb_ctx *ctx) 182 { 183 int i; 184 185 for (i = 0; i < ctx->packets; ++i) 186 ctx->packet_size[i] = next_packet_size(ep); 187 } 188 189 /* 190 * Prepare a PLAYBACK urb for submission to the bus. 191 */ 192 static void prepare_outbound_urb(struct snd_usb_endpoint *ep, 193 struct snd_urb_ctx *ctx) 194 { 195 int i; 196 struct urb *urb = ctx->urb; 197 unsigned char *cp = urb->transfer_buffer; 198 199 urb->dev = ep->chip->dev; /* we need to set this at each time */ 200 201 switch (ep->type) { 202 case SND_USB_ENDPOINT_TYPE_DATA: 203 if (ep->prepare_data_urb) { 204 ep->prepare_data_urb(ep->data_subs, urb); 205 } else { 206 /* no data provider, so send silence */ 207 unsigned int offs = 0; 208 for (i = 0; i < ctx->packets; ++i) { 209 int counts = ctx->packet_size[i]; 210 urb->iso_frame_desc[i].offset = offs * ep->stride; 211 urb->iso_frame_desc[i].length = counts * ep->stride; 212 offs += counts; 213 } 214 215 urb->number_of_packets = ctx->packets; 216 urb->transfer_buffer_length = offs * ep->stride; 217 memset(urb->transfer_buffer, ep->silence_value, 218 offs * ep->stride); 219 } 220 break; 221 222 case SND_USB_ENDPOINT_TYPE_SYNC: 223 if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) { 224 /* 225 * fill the length and offset of each urb descriptor. 226 * the fixed 12.13 frequency is passed as 16.16 through the pipe. 227 */ 228 urb->iso_frame_desc[0].length = 4; 229 urb->iso_frame_desc[0].offset = 0; 230 cp[0] = ep->freqn; 231 cp[1] = ep->freqn >> 8; 232 cp[2] = ep->freqn >> 16; 233 cp[3] = ep->freqn >> 24; 234 } else { 235 /* 236 * fill the length and offset of each urb descriptor. 237 * the fixed 10.14 frequency is passed through the pipe. 238 */ 239 urb->iso_frame_desc[0].length = 3; 240 urb->iso_frame_desc[0].offset = 0; 241 cp[0] = ep->freqn >> 2; 242 cp[1] = ep->freqn >> 10; 243 cp[2] = ep->freqn >> 18; 244 } 245 246 break; 247 } 248 } 249 250 /* 251 * Prepare a CAPTURE or SYNC urb for submission to the bus. 252 */ 253 static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep, 254 struct snd_urb_ctx *urb_ctx) 255 { 256 int i, offs; 257 struct urb *urb = urb_ctx->urb; 258 259 urb->dev = ep->chip->dev; /* we need to set this at each time */ 260 261 switch (ep->type) { 262 case SND_USB_ENDPOINT_TYPE_DATA: 263 offs = 0; 264 for (i = 0; i < urb_ctx->packets; i++) { 265 urb->iso_frame_desc[i].offset = offs; 266 urb->iso_frame_desc[i].length = ep->curpacksize; 267 offs += ep->curpacksize; 268 } 269 270 urb->transfer_buffer_length = offs; 271 urb->number_of_packets = urb_ctx->packets; 272 break; 273 274 case SND_USB_ENDPOINT_TYPE_SYNC: 275 urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize); 276 urb->iso_frame_desc[0].offset = 0; 277 break; 278 } 279 } 280 281 /* 282 * Send output urbs that have been prepared previously. URBs are dequeued 283 * from ep->ready_playback_urbs and in case there there aren't any available 284 * or there are no packets that have been prepared, this function does 285 * nothing. 286 * 287 * The reason why the functionality of sending and preparing URBs is separated 288 * is that host controllers don't guarantee the order in which they return 289 * inbound and outbound packets to their submitters. 290 * 291 * This function is only used for implicit feedback endpoints. For endpoints 292 * driven by dedicated sync endpoints, URBs are immediately re-submitted 293 * from their completion handler. 294 */ 295 static void queue_pending_output_urbs(struct snd_usb_endpoint *ep) 296 { 297 while (test_bit(EP_FLAG_RUNNING, &ep->flags)) { 298 299 unsigned long flags; 300 struct snd_usb_packet_info *uninitialized_var(packet); 301 struct snd_urb_ctx *ctx = NULL; 302 struct urb *urb; 303 int err, i; 304 305 spin_lock_irqsave(&ep->lock, flags); 306 if (ep->next_packet_read_pos != ep->next_packet_write_pos) { 307 packet = ep->next_packet + ep->next_packet_read_pos; 308 ep->next_packet_read_pos++; 309 ep->next_packet_read_pos %= MAX_URBS; 310 311 /* take URB out of FIFO */ 312 if (!list_empty(&ep->ready_playback_urbs)) 313 ctx = list_first_entry(&ep->ready_playback_urbs, 314 struct snd_urb_ctx, ready_list); 315 } 316 spin_unlock_irqrestore(&ep->lock, flags); 317 318 if (ctx == NULL) 319 return; 320 321 list_del_init(&ctx->ready_list); 322 urb = ctx->urb; 323 324 /* copy over the length information */ 325 for (i = 0; i < packet->packets; i++) 326 ctx->packet_size[i] = packet->packet_size[i]; 327 328 /* call the data handler to fill in playback data */ 329 prepare_outbound_urb(ep, ctx); 330 331 err = usb_submit_urb(ctx->urb, GFP_ATOMIC); 332 if (err < 0) 333 snd_printk(KERN_ERR "Unable to submit urb #%d: %d (urb %p)\n", 334 ctx->index, err, ctx->urb); 335 else 336 set_bit(ctx->index, &ep->active_mask); 337 } 338 } 339 340 /* 341 * complete callback for urbs 342 */ 343 static void snd_complete_urb(struct urb *urb) 344 { 345 struct snd_urb_ctx *ctx = urb->context; 346 struct snd_usb_endpoint *ep = ctx->ep; 347 int err; 348 349 if (unlikely(urb->status == -ENOENT || /* unlinked */ 350 urb->status == -ENODEV || /* device removed */ 351 urb->status == -ECONNRESET || /* unlinked */ 352 urb->status == -ESHUTDOWN || /* device disabled */ 353 ep->chip->shutdown)) /* device disconnected */ 354 goto exit_clear; 355 356 if (usb_pipeout(ep->pipe)) { 357 retire_outbound_urb(ep, ctx); 358 /* can be stopped during retire callback */ 359 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags))) 360 goto exit_clear; 361 362 if (snd_usb_endpoint_implict_feedback_sink(ep)) { 363 unsigned long flags; 364 365 spin_lock_irqsave(&ep->lock, flags); 366 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs); 367 spin_unlock_irqrestore(&ep->lock, flags); 368 queue_pending_output_urbs(ep); 369 370 goto exit_clear; 371 } 372 373 prepare_outbound_urb_sizes(ep, ctx); 374 prepare_outbound_urb(ep, ctx); 375 } else { 376 retire_inbound_urb(ep, ctx); 377 /* can be stopped during retire callback */ 378 if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags))) 379 goto exit_clear; 380 381 prepare_inbound_urb(ep, ctx); 382 } 383 384 err = usb_submit_urb(urb, GFP_ATOMIC); 385 if (err == 0) 386 return; 387 388 snd_printk(KERN_ERR "cannot submit urb (err = %d)\n", err); 389 //snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN); 390 391 exit_clear: 392 clear_bit(ctx->index, &ep->active_mask); 393 } 394 395 /** 396 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip 397 * 398 * @chip: The chip 399 * @alts: The USB host interface 400 * @ep_num: The number of the endpoint to use 401 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE 402 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC 403 * 404 * If the requested endpoint has not been added to the given chip before, 405 * a new instance is created. Otherwise, a pointer to the previoulsy 406 * created instance is returned. In case of any error, NULL is returned. 407 * 408 * New endpoints will be added to chip->ep_list and must be freed by 409 * calling snd_usb_endpoint_free(). 410 */ 411 struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip, 412 struct usb_host_interface *alts, 413 int ep_num, int direction, int type) 414 { 415 struct list_head *p; 416 struct snd_usb_endpoint *ep; 417 int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK; 418 419 mutex_lock(&chip->mutex); 420 421 list_for_each(p, &chip->ep_list) { 422 ep = list_entry(p, struct snd_usb_endpoint, list); 423 if (ep->ep_num == ep_num && 424 ep->iface == alts->desc.bInterfaceNumber && 425 ep->alt_idx == alts->desc.bAlternateSetting) { 426 snd_printdd(KERN_DEBUG "Re-using EP %x in iface %d,%d @%p\n", 427 ep_num, ep->iface, ep->alt_idx, ep); 428 goto __exit_unlock; 429 } 430 } 431 432 snd_printdd(KERN_DEBUG "Creating new %s %s endpoint #%x\n", 433 is_playback ? "playback" : "capture", 434 type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync", 435 ep_num); 436 437 ep = kzalloc(sizeof(*ep), GFP_KERNEL); 438 if (!ep) 439 goto __exit_unlock; 440 441 ep->chip = chip; 442 spin_lock_init(&ep->lock); 443 ep->type = type; 444 ep->ep_num = ep_num; 445 ep->iface = alts->desc.bInterfaceNumber; 446 ep->alt_idx = alts->desc.bAlternateSetting; 447 INIT_LIST_HEAD(&ep->ready_playback_urbs); 448 ep_num &= USB_ENDPOINT_NUMBER_MASK; 449 450 if (is_playback) 451 ep->pipe = usb_sndisocpipe(chip->dev, ep_num); 452 else 453 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num); 454 455 if (type == SND_USB_ENDPOINT_TYPE_SYNC) { 456 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE && 457 get_endpoint(alts, 1)->bRefresh >= 1 && 458 get_endpoint(alts, 1)->bRefresh <= 9) 459 ep->syncinterval = get_endpoint(alts, 1)->bRefresh; 460 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) 461 ep->syncinterval = 1; 462 else if (get_endpoint(alts, 1)->bInterval >= 1 && 463 get_endpoint(alts, 1)->bInterval <= 16) 464 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1; 465 else 466 ep->syncinterval = 3; 467 468 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize); 469 } 470 471 list_add_tail(&ep->list, &chip->ep_list); 472 473 __exit_unlock: 474 mutex_unlock(&chip->mutex); 475 476 return ep; 477 } 478 479 /* 480 * wait until all urbs are processed. 481 */ 482 static int wait_clear_urbs(struct snd_usb_endpoint *ep) 483 { 484 unsigned long end_time = jiffies + msecs_to_jiffies(1000); 485 unsigned int i; 486 int alive; 487 488 do { 489 alive = 0; 490 for (i = 0; i < ep->nurbs; i++) 491 if (test_bit(i, &ep->active_mask)) 492 alive++; 493 494 if (!alive) 495 break; 496 497 schedule_timeout_uninterruptible(1); 498 } while (time_before(jiffies, end_time)); 499 500 if (alive) 501 snd_printk(KERN_ERR "timeout: still %d active urbs on EP #%x\n", 502 alive, ep->ep_num); 503 504 return 0; 505 } 506 507 /* 508 * unlink active urbs. 509 */ 510 static int deactivate_urbs(struct snd_usb_endpoint *ep, int force, int can_sleep) 511 { 512 unsigned int i; 513 int async; 514 515 if (!force && ep->chip->shutdown) /* to be sure... */ 516 return -EBADFD; 517 518 async = !can_sleep && ep->chip->async_unlink; 519 520 clear_bit(EP_FLAG_RUNNING, &ep->flags); 521 522 INIT_LIST_HEAD(&ep->ready_playback_urbs); 523 ep->next_packet_read_pos = 0; 524 ep->next_packet_write_pos = 0; 525 526 if (!async && in_interrupt()) 527 return 0; 528 529 for (i = 0; i < ep->nurbs; i++) { 530 if (test_bit(i, &ep->active_mask)) { 531 if (!test_and_set_bit(i, &ep->unlink_mask)) { 532 struct urb *u = ep->urb[i].urb; 533 if (async) 534 usb_unlink_urb(u); 535 else 536 usb_kill_urb(u); 537 } 538 } 539 } 540 541 return 0; 542 } 543 544 /* 545 * release an endpoint's urbs 546 */ 547 static void release_urbs(struct snd_usb_endpoint *ep, int force) 548 { 549 int i; 550 551 /* route incoming urbs to nirvana */ 552 ep->retire_data_urb = NULL; 553 ep->prepare_data_urb = NULL; 554 555 /* stop urbs */ 556 deactivate_urbs(ep, force, 1); 557 wait_clear_urbs(ep); 558 559 for (i = 0; i < ep->nurbs; i++) 560 release_urb_ctx(&ep->urb[i]); 561 562 if (ep->syncbuf) 563 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4, 564 ep->syncbuf, ep->sync_dma); 565 566 ep->syncbuf = NULL; 567 ep->nurbs = 0; 568 } 569 570 /* 571 * configure a data endpoint 572 */ 573 static int data_ep_set_params(struct snd_usb_endpoint *ep, 574 struct snd_pcm_hw_params *hw_params, 575 struct audioformat *fmt, 576 struct snd_usb_endpoint *sync_ep) 577 { 578 unsigned int maxsize, i, urb_packs, total_packs, packs_per_ms; 579 int period_bytes = params_period_bytes(hw_params); 580 int format = params_format(hw_params); 581 int is_playback = usb_pipeout(ep->pipe); 582 int frame_bits = snd_pcm_format_physical_width(params_format(hw_params)) * 583 params_channels(hw_params); 584 585 ep->datainterval = fmt->datainterval; 586 ep->stride = frame_bits >> 3; 587 ep->silence_value = format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0; 588 589 /* calculate max. frequency */ 590 if (ep->maxpacksize) { 591 /* whatever fits into a max. size packet */ 592 maxsize = ep->maxpacksize; 593 ep->freqmax = (maxsize / (frame_bits >> 3)) 594 << (16 - ep->datainterval); 595 } else { 596 /* no max. packet size: just take 25% higher than nominal */ 597 ep->freqmax = ep->freqn + (ep->freqn >> 2); 598 maxsize = ((ep->freqmax + 0xffff) * (frame_bits >> 3)) 599 >> (16 - ep->datainterval); 600 } 601 602 if (ep->fill_max) 603 ep->curpacksize = ep->maxpacksize; 604 else 605 ep->curpacksize = maxsize; 606 607 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) 608 packs_per_ms = 8 >> ep->datainterval; 609 else 610 packs_per_ms = 1; 611 612 if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) { 613 urb_packs = max(ep->chip->nrpacks, 1); 614 urb_packs = min(urb_packs, (unsigned int) MAX_PACKS); 615 } else { 616 urb_packs = 1; 617 } 618 619 urb_packs *= packs_per_ms; 620 621 if (sync_ep && !snd_usb_endpoint_implict_feedback_sink(ep)) 622 urb_packs = min(urb_packs, 1U << sync_ep->syncinterval); 623 624 /* decide how many packets to be used */ 625 if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) { 626 unsigned int minsize, maxpacks; 627 /* determine how small a packet can be */ 628 minsize = (ep->freqn >> (16 - ep->datainterval)) 629 * (frame_bits >> 3); 630 /* with sync from device, assume it can be 12% lower */ 631 if (sync_ep) 632 minsize -= minsize >> 3; 633 minsize = max(minsize, 1u); 634 total_packs = (period_bytes + minsize - 1) / minsize; 635 /* we need at least two URBs for queueing */ 636 if (total_packs < 2) { 637 total_packs = 2; 638 } else { 639 /* and we don't want too long a queue either */ 640 maxpacks = max(MAX_QUEUE * packs_per_ms, urb_packs * 2); 641 total_packs = min(total_packs, maxpacks); 642 } 643 } else { 644 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes) 645 urb_packs >>= 1; 646 total_packs = MAX_URBS * urb_packs; 647 } 648 649 ep->nurbs = (total_packs + urb_packs - 1) / urb_packs; 650 if (ep->nurbs > MAX_URBS) { 651 /* too much... */ 652 ep->nurbs = MAX_URBS; 653 total_packs = MAX_URBS * urb_packs; 654 } else if (ep->nurbs < 2) { 655 /* too little - we need at least two packets 656 * to ensure contiguous playback/capture 657 */ 658 ep->nurbs = 2; 659 } 660 661 /* allocate and initialize data urbs */ 662 for (i = 0; i < ep->nurbs; i++) { 663 struct snd_urb_ctx *u = &ep->urb[i]; 664 u->index = i; 665 u->ep = ep; 666 u->packets = (i + 1) * total_packs / ep->nurbs 667 - i * total_packs / ep->nurbs; 668 u->buffer_size = maxsize * u->packets; 669 670 if (fmt->fmt_type == UAC_FORMAT_TYPE_II) 671 u->packets++; /* for transfer delimiter */ 672 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL); 673 if (!u->urb) 674 goto out_of_memory; 675 676 u->urb->transfer_buffer = 677 usb_alloc_coherent(ep->chip->dev, u->buffer_size, 678 GFP_KERNEL, &u->urb->transfer_dma); 679 if (!u->urb->transfer_buffer) 680 goto out_of_memory; 681 u->urb->pipe = ep->pipe; 682 u->urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; 683 u->urb->interval = 1 << ep->datainterval; 684 u->urb->context = u; 685 u->urb->complete = snd_complete_urb; 686 INIT_LIST_HEAD(&u->ready_list); 687 } 688 689 return 0; 690 691 out_of_memory: 692 release_urbs(ep, 0); 693 return -ENOMEM; 694 } 695 696 /* 697 * configure a sync endpoint 698 */ 699 static int sync_ep_set_params(struct snd_usb_endpoint *ep, 700 struct snd_pcm_hw_params *hw_params, 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 * @hw_params: the hardware parameters 744 * @fmt: the USB audio format information 745 * @sync_ep: the sync endpoint to use, if any 746 * 747 * Determine the number of URBs to be used on this endpoint. 748 * An endpoint must be configured before it can be started. 749 * An endpoint that is already running can not be reconfigured. 750 */ 751 int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep, 752 struct snd_pcm_hw_params *hw_params, 753 struct audioformat *fmt, 754 struct snd_usb_endpoint *sync_ep) 755 { 756 int err; 757 758 if (ep->use_count != 0) { 759 snd_printk(KERN_WARNING "Unable to change format on ep #%x: already in use\n", 760 ep->ep_num); 761 return -EBUSY; 762 } 763 764 /* release old buffers, if any */ 765 release_urbs(ep, 0); 766 767 ep->datainterval = fmt->datainterval; 768 ep->maxpacksize = fmt->maxpacksize; 769 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX); 770 771 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL) 772 ep->freqn = get_usb_full_speed_rate(params_rate(hw_params)); 773 else 774 ep->freqn = get_usb_high_speed_rate(params_rate(hw_params)); 775 776 /* calculate the frequency in 16.16 format */ 777 ep->freqm = ep->freqn; 778 ep->freqshift = INT_MIN; 779 780 ep->phase = 0; 781 782 switch (ep->type) { 783 case SND_USB_ENDPOINT_TYPE_DATA: 784 err = data_ep_set_params(ep, hw_params, fmt, sync_ep); 785 break; 786 case SND_USB_ENDPOINT_TYPE_SYNC: 787 err = sync_ep_set_params(ep, hw_params, fmt); 788 break; 789 default: 790 err = -EINVAL; 791 } 792 793 snd_printdd(KERN_DEBUG "Setting params for ep #%x (type %d, %d urbs), ret=%d\n", 794 ep->ep_num, ep->type, ep->nurbs, err); 795 796 return err; 797 } 798 799 /** 800 * snd_usb_endpoint_start: start an snd_usb_endpoint 801 * 802 * @ep: the endpoint to start 803 * 804 * A call to this function will increment the use count of the endpoint. 805 * In case it is not already running, the URBs for this endpoint will be 806 * submitted. Otherwise, this function does nothing. 807 * 808 * Must be balanced to calls of snd_usb_endpoint_stop(). 809 * 810 * Returns an error if the URB submission failed, 0 in all other cases. 811 */ 812 int snd_usb_endpoint_start(struct snd_usb_endpoint *ep) 813 { 814 int err; 815 unsigned int i; 816 817 if (ep->chip->shutdown) 818 return -EBADFD; 819 820 /* already running? */ 821 if (++ep->use_count != 1) 822 return 0; 823 824 /* just to be sure */ 825 deactivate_urbs(ep, 0, 1); 826 wait_clear_urbs(ep); 827 828 ep->active_mask = 0; 829 ep->unlink_mask = 0; 830 ep->phase = 0; 831 832 /* 833 * If this endpoint has a data endpoint as implicit feedback source, 834 * don't start the urbs here. Instead, mark them all as available, 835 * wait for the record urbs to return and queue the playback urbs 836 * from that context. 837 */ 838 839 set_bit(EP_FLAG_RUNNING, &ep->flags); 840 841 if (snd_usb_endpoint_implict_feedback_sink(ep)) { 842 for (i = 0; i < ep->nurbs; i++) { 843 struct snd_urb_ctx *ctx = ep->urb + i; 844 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs); 845 } 846 847 return 0; 848 } 849 850 for (i = 0; i < ep->nurbs; i++) { 851 struct urb *urb = ep->urb[i].urb; 852 853 if (snd_BUG_ON(!urb)) 854 goto __error; 855 856 if (usb_pipeout(ep->pipe)) { 857 prepare_outbound_urb_sizes(ep, urb->context); 858 prepare_outbound_urb(ep, urb->context); 859 } else { 860 prepare_inbound_urb(ep, urb->context); 861 } 862 863 err = usb_submit_urb(urb, GFP_ATOMIC); 864 if (err < 0) { 865 snd_printk(KERN_ERR "cannot submit urb %d, error %d: %s\n", 866 i, err, usb_error_string(err)); 867 goto __error; 868 } 869 set_bit(i, &ep->active_mask); 870 } 871 872 return 0; 873 874 __error: 875 clear_bit(EP_FLAG_RUNNING, &ep->flags); 876 ep->use_count--; 877 deactivate_urbs(ep, 0, 0); 878 return -EPIPE; 879 } 880 881 /** 882 * snd_usb_endpoint_stop: stop an snd_usb_endpoint 883 * 884 * @ep: the endpoint to stop (may be NULL) 885 * 886 * A call to this function will decrement the use count of the endpoint. 887 * In case the last user has requested the endpoint stop, the URBs will 888 * actually be deactivated. 889 * 890 * Must be balanced to calls of snd_usb_endpoint_start(). 891 */ 892 void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep, 893 int force, int can_sleep, int wait) 894 { 895 if (!ep) 896 return; 897 898 if (snd_BUG_ON(ep->use_count == 0)) 899 return; 900 901 if (--ep->use_count == 0) { 902 deactivate_urbs(ep, force, can_sleep); 903 ep->data_subs = NULL; 904 ep->sync_slave = NULL; 905 ep->retire_data_urb = NULL; 906 ep->prepare_data_urb = NULL; 907 908 if (wait) 909 wait_clear_urbs(ep); 910 } 911 } 912 913 /** 914 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint 915 * 916 * @ep: the endpoint to deactivate 917 * 918 * If the endpoint is not currently in use, this functions will select the 919 * alternate interface setting 0 for the interface of this endpoint. 920 * 921 * In case of any active users, this functions does nothing. 922 * 923 * Returns an error if usb_set_interface() failed, 0 in all other 924 * cases. 925 */ 926 int snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep) 927 { 928 if (!ep) 929 return -EINVAL; 930 931 deactivate_urbs(ep, 1, 1); 932 wait_clear_urbs(ep); 933 934 if (ep->use_count != 0) 935 return 0; 936 937 clear_bit(EP_FLAG_ACTIVATED, &ep->flags); 938 939 return 0; 940 } 941 942 /** 943 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint 944 * 945 * @ep: the list header of the endpoint to free 946 * 947 * This function does not care for the endpoint's use count but will tear 948 * down all the streaming URBs immediately and free all resources. 949 */ 950 void snd_usb_endpoint_free(struct list_head *head) 951 { 952 struct snd_usb_endpoint *ep; 953 954 ep = list_entry(head, struct snd_usb_endpoint, list); 955 release_urbs(ep, 1); 956 kfree(ep); 957 } 958 959 /** 960 * snd_usb_handle_sync_urb: parse an USB sync packet 961 * 962 * @ep: the endpoint to handle the packet 963 * @sender: the sending endpoint 964 * @urb: the received packet 965 * 966 * This function is called from the context of an endpoint that received 967 * the packet and is used to let another endpoint object handle the payload. 968 */ 969 void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep, 970 struct snd_usb_endpoint *sender, 971 const struct urb *urb) 972 { 973 int shift; 974 unsigned int f; 975 unsigned long flags; 976 977 snd_BUG_ON(ep == sender); 978 979 /* 980 * In case the endpoint is operating in implicit feedback mode, prepare 981 * a new outbound URB that has the same layout as the received packet 982 * and add it to the list of pending urbs. queue_pending_output_urbs() 983 * will take care of them later. 984 */ 985 if (snd_usb_endpoint_implict_feedback_sink(ep) && 986 ep->use_count != 0) { 987 988 /* implicit feedback case */ 989 int i, bytes = 0; 990 struct snd_urb_ctx *in_ctx; 991 struct snd_usb_packet_info *out_packet; 992 993 in_ctx = urb->context; 994 995 /* Count overall packet size */ 996 for (i = 0; i < in_ctx->packets; i++) 997 if (urb->iso_frame_desc[i].status == 0) 998 bytes += urb->iso_frame_desc[i].actual_length; 999 1000 /* 1001 * skip empty packets. At least M-Audio's Fast Track Ultra stops 1002 * streaming once it received a 0-byte OUT URB 1003 */ 1004 if (bytes == 0) 1005 return; 1006 1007 spin_lock_irqsave(&ep->lock, flags); 1008 out_packet = ep->next_packet + ep->next_packet_write_pos; 1009 1010 /* 1011 * Iterate through the inbound packet and prepare the lengths 1012 * for the output packet. The OUT packet we are about to send 1013 * will have the same amount of payload bytes than the IN 1014 * packet we just received. 1015 */ 1016 1017 out_packet->packets = in_ctx->packets; 1018 for (i = 0; i < in_ctx->packets; i++) { 1019 if (urb->iso_frame_desc[i].status == 0) 1020 out_packet->packet_size[i] = 1021 urb->iso_frame_desc[i].actual_length / ep->stride; 1022 else 1023 out_packet->packet_size[i] = 0; 1024 } 1025 1026 ep->next_packet_write_pos++; 1027 ep->next_packet_write_pos %= MAX_URBS; 1028 spin_unlock_irqrestore(&ep->lock, flags); 1029 queue_pending_output_urbs(ep); 1030 1031 return; 1032 } 1033 1034 /* 1035 * process after playback sync complete 1036 * 1037 * Full speed devices report feedback values in 10.14 format as samples 1038 * per frame, high speed devices in 16.16 format as samples per 1039 * microframe. 1040 * 1041 * Because the Audio Class 1 spec was written before USB 2.0, many high 1042 * speed devices use a wrong interpretation, some others use an 1043 * entirely different format. 1044 * 1045 * Therefore, we cannot predict what format any particular device uses 1046 * and must detect it automatically. 1047 */ 1048 1049 if (urb->iso_frame_desc[0].status != 0 || 1050 urb->iso_frame_desc[0].actual_length < 3) 1051 return; 1052 1053 f = le32_to_cpup(urb->transfer_buffer); 1054 if (urb->iso_frame_desc[0].actual_length == 3) 1055 f &= 0x00ffffff; 1056 else 1057 f &= 0x0fffffff; 1058 1059 if (f == 0) 1060 return; 1061 1062 if (unlikely(ep->freqshift == INT_MIN)) { 1063 /* 1064 * The first time we see a feedback value, determine its format 1065 * by shifting it left or right until it matches the nominal 1066 * frequency value. This assumes that the feedback does not 1067 * differ from the nominal value more than +50% or -25%. 1068 */ 1069 shift = 0; 1070 while (f < ep->freqn - ep->freqn / 4) { 1071 f <<= 1; 1072 shift++; 1073 } 1074 while (f > ep->freqn + ep->freqn / 2) { 1075 f >>= 1; 1076 shift--; 1077 } 1078 ep->freqshift = shift; 1079 } else if (ep->freqshift >= 0) 1080 f <<= ep->freqshift; 1081 else 1082 f >>= -ep->freqshift; 1083 1084 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) { 1085 /* 1086 * If the frequency looks valid, set it. 1087 * This value is referred to in prepare_playback_urb(). 1088 */ 1089 spin_lock_irqsave(&ep->lock, flags); 1090 ep->freqm = f; 1091 spin_unlock_irqrestore(&ep->lock, flags); 1092 } else { 1093 /* 1094 * Out of range; maybe the shift value is wrong. 1095 * Reset it so that we autodetect again the next time. 1096 */ 1097 ep->freqshift = INT_MIN; 1098 } 1099 } 1100 1101