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 ret, 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 /* select the alt setting once so the endpoints become valid */ 438 ret = usb_set_interface(chip->dev, alts->desc.bInterfaceNumber, 439 alts->desc.bAlternateSetting); 440 if (ret < 0) { 441 snd_printk(KERN_ERR "%s(): usb_set_interface() failed, ret = %d\n", 442 __func__, ret); 443 ep = NULL; 444 goto __exit_unlock; 445 } 446 447 ep = kzalloc(sizeof(*ep), GFP_KERNEL); 448 if (!ep) 449 goto __exit_unlock; 450 451 ep->chip = chip; 452 spin_lock_init(&ep->lock); 453 ep->type = type; 454 ep->ep_num = ep_num; 455 ep->iface = alts->desc.bInterfaceNumber; 456 ep->alt_idx = alts->desc.bAlternateSetting; 457 INIT_LIST_HEAD(&ep->ready_playback_urbs); 458 ep_num &= USB_ENDPOINT_NUMBER_MASK; 459 460 if (is_playback) 461 ep->pipe = usb_sndisocpipe(chip->dev, ep_num); 462 else 463 ep->pipe = usb_rcvisocpipe(chip->dev, ep_num); 464 465 if (type == SND_USB_ENDPOINT_TYPE_SYNC) { 466 if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE && 467 get_endpoint(alts, 1)->bRefresh >= 1 && 468 get_endpoint(alts, 1)->bRefresh <= 9) 469 ep->syncinterval = get_endpoint(alts, 1)->bRefresh; 470 else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) 471 ep->syncinterval = 1; 472 else if (get_endpoint(alts, 1)->bInterval >= 1 && 473 get_endpoint(alts, 1)->bInterval <= 16) 474 ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1; 475 else 476 ep->syncinterval = 3; 477 478 ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize); 479 } 480 481 list_add_tail(&ep->list, &chip->ep_list); 482 483 __exit_unlock: 484 mutex_unlock(&chip->mutex); 485 486 return ep; 487 } 488 489 /* 490 * wait until all urbs are processed. 491 */ 492 static int wait_clear_urbs(struct snd_usb_endpoint *ep) 493 { 494 unsigned long end_time = jiffies + msecs_to_jiffies(1000); 495 unsigned int i; 496 int alive; 497 498 do { 499 alive = 0; 500 for (i = 0; i < ep->nurbs; i++) 501 if (test_bit(i, &ep->active_mask)) 502 alive++; 503 504 if (!alive) 505 break; 506 507 schedule_timeout_uninterruptible(1); 508 } while (time_before(jiffies, end_time)); 509 510 if (alive) 511 snd_printk(KERN_ERR "timeout: still %d active urbs on EP #%x\n", 512 alive, ep->ep_num); 513 514 return 0; 515 } 516 517 /* 518 * unlink active urbs. 519 */ 520 static int deactivate_urbs(struct snd_usb_endpoint *ep, int force, int can_sleep) 521 { 522 unsigned int i; 523 int async; 524 525 if (!force && ep->chip->shutdown) /* to be sure... */ 526 return -EBADFD; 527 528 async = !can_sleep && ep->chip->async_unlink; 529 530 clear_bit(EP_FLAG_RUNNING, &ep->flags); 531 532 INIT_LIST_HEAD(&ep->ready_playback_urbs); 533 ep->next_packet_read_pos = 0; 534 ep->next_packet_write_pos = 0; 535 536 if (!async && in_interrupt()) 537 return 0; 538 539 for (i = 0; i < ep->nurbs; i++) { 540 if (test_bit(i, &ep->active_mask)) { 541 if (!test_and_set_bit(i, &ep->unlink_mask)) { 542 struct urb *u = ep->urb[i].urb; 543 if (async) 544 usb_unlink_urb(u); 545 else 546 usb_kill_urb(u); 547 } 548 } 549 } 550 551 return 0; 552 } 553 554 /* 555 * release an endpoint's urbs 556 */ 557 static void release_urbs(struct snd_usb_endpoint *ep, int force) 558 { 559 int i; 560 561 /* route incoming urbs to nirvana */ 562 ep->retire_data_urb = NULL; 563 ep->prepare_data_urb = NULL; 564 565 /* stop urbs */ 566 deactivate_urbs(ep, force, 1); 567 wait_clear_urbs(ep); 568 569 for (i = 0; i < ep->nurbs; i++) 570 release_urb_ctx(&ep->urb[i]); 571 572 if (ep->syncbuf) 573 usb_free_coherent(ep->chip->dev, SYNC_URBS * 4, 574 ep->syncbuf, ep->sync_dma); 575 576 ep->syncbuf = NULL; 577 ep->nurbs = 0; 578 } 579 580 /* 581 * configure a data endpoint 582 */ 583 static int data_ep_set_params(struct snd_usb_endpoint *ep, 584 struct snd_pcm_hw_params *hw_params, 585 struct audioformat *fmt, 586 struct snd_usb_endpoint *sync_ep) 587 { 588 unsigned int maxsize, i, urb_packs, total_packs, packs_per_ms; 589 int period_bytes = params_period_bytes(hw_params); 590 int format = params_format(hw_params); 591 int is_playback = usb_pipeout(ep->pipe); 592 int frame_bits = snd_pcm_format_physical_width(params_format(hw_params)) * 593 params_channels(hw_params); 594 595 ep->datainterval = fmt->datainterval; 596 ep->stride = frame_bits >> 3; 597 ep->silence_value = format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0; 598 599 /* calculate max. frequency */ 600 if (ep->maxpacksize) { 601 /* whatever fits into a max. size packet */ 602 maxsize = ep->maxpacksize; 603 ep->freqmax = (maxsize / (frame_bits >> 3)) 604 << (16 - ep->datainterval); 605 } else { 606 /* no max. packet size: just take 25% higher than nominal */ 607 ep->freqmax = ep->freqn + (ep->freqn >> 2); 608 maxsize = ((ep->freqmax + 0xffff) * (frame_bits >> 3)) 609 >> (16 - ep->datainterval); 610 } 611 612 if (ep->fill_max) 613 ep->curpacksize = ep->maxpacksize; 614 else 615 ep->curpacksize = maxsize; 616 617 if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) 618 packs_per_ms = 8 >> ep->datainterval; 619 else 620 packs_per_ms = 1; 621 622 if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) { 623 urb_packs = max(ep->chip->nrpacks, 1); 624 urb_packs = min(urb_packs, (unsigned int) MAX_PACKS); 625 } else { 626 urb_packs = 1; 627 } 628 629 urb_packs *= packs_per_ms; 630 631 if (sync_ep && !snd_usb_endpoint_implict_feedback_sink(ep)) 632 urb_packs = min(urb_packs, 1U << sync_ep->syncinterval); 633 634 /* decide how many packets to be used */ 635 if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) { 636 unsigned int minsize, maxpacks; 637 /* determine how small a packet can be */ 638 minsize = (ep->freqn >> (16 - ep->datainterval)) 639 * (frame_bits >> 3); 640 /* with sync from device, assume it can be 12% lower */ 641 if (sync_ep) 642 minsize -= minsize >> 3; 643 minsize = max(minsize, 1u); 644 total_packs = (period_bytes + minsize - 1) / minsize; 645 /* we need at least two URBs for queueing */ 646 if (total_packs < 2) { 647 total_packs = 2; 648 } else { 649 /* and we don't want too long a queue either */ 650 maxpacks = max(MAX_QUEUE * packs_per_ms, urb_packs * 2); 651 total_packs = min(total_packs, maxpacks); 652 } 653 } else { 654 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes) 655 urb_packs >>= 1; 656 total_packs = MAX_URBS * urb_packs; 657 } 658 659 ep->nurbs = (total_packs + urb_packs - 1) / urb_packs; 660 if (ep->nurbs > MAX_URBS) { 661 /* too much... */ 662 ep->nurbs = MAX_URBS; 663 total_packs = MAX_URBS * urb_packs; 664 } else if (ep->nurbs < 2) { 665 /* too little - we need at least two packets 666 * to ensure contiguous playback/capture 667 */ 668 ep->nurbs = 2; 669 } 670 671 /* allocate and initialize data urbs */ 672 for (i = 0; i < ep->nurbs; i++) { 673 struct snd_urb_ctx *u = &ep->urb[i]; 674 u->index = i; 675 u->ep = ep; 676 u->packets = (i + 1) * total_packs / ep->nurbs 677 - i * total_packs / ep->nurbs; 678 u->buffer_size = maxsize * u->packets; 679 680 if (fmt->fmt_type == UAC_FORMAT_TYPE_II) 681 u->packets++; /* for transfer delimiter */ 682 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL); 683 if (!u->urb) 684 goto out_of_memory; 685 686 u->urb->transfer_buffer = 687 usb_alloc_coherent(ep->chip->dev, u->buffer_size, 688 GFP_KERNEL, &u->urb->transfer_dma); 689 if (!u->urb->transfer_buffer) 690 goto out_of_memory; 691 u->urb->pipe = ep->pipe; 692 u->urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; 693 u->urb->interval = 1 << ep->datainterval; 694 u->urb->context = u; 695 u->urb->complete = snd_complete_urb; 696 INIT_LIST_HEAD(&u->ready_list); 697 } 698 699 return 0; 700 701 out_of_memory: 702 release_urbs(ep, 0); 703 return -ENOMEM; 704 } 705 706 /* 707 * configure a sync endpoint 708 */ 709 static int sync_ep_set_params(struct snd_usb_endpoint *ep, 710 struct snd_pcm_hw_params *hw_params, 711 struct audioformat *fmt) 712 { 713 int i; 714 715 ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4, 716 GFP_KERNEL, &ep->sync_dma); 717 if (!ep->syncbuf) 718 return -ENOMEM; 719 720 for (i = 0; i < SYNC_URBS; i++) { 721 struct snd_urb_ctx *u = &ep->urb[i]; 722 u->index = i; 723 u->ep = ep; 724 u->packets = 1; 725 u->urb = usb_alloc_urb(1, GFP_KERNEL); 726 if (!u->urb) 727 goto out_of_memory; 728 u->urb->transfer_buffer = ep->syncbuf + i * 4; 729 u->urb->transfer_dma = ep->sync_dma + i * 4; 730 u->urb->transfer_buffer_length = 4; 731 u->urb->pipe = ep->pipe; 732 u->urb->transfer_flags = URB_ISO_ASAP | 733 URB_NO_TRANSFER_DMA_MAP; 734 u->urb->number_of_packets = 1; 735 u->urb->interval = 1 << ep->syncinterval; 736 u->urb->context = u; 737 u->urb->complete = snd_complete_urb; 738 } 739 740 ep->nurbs = SYNC_URBS; 741 742 return 0; 743 744 out_of_memory: 745 release_urbs(ep, 0); 746 return -ENOMEM; 747 } 748 749 /** 750 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint 751 * 752 * @ep: the snd_usb_endpoint to configure 753 * @hw_params: the hardware parameters 754 * @fmt: the USB audio format information 755 * @sync_ep: the sync endpoint to use, if any 756 * 757 * Determine the number of URBs to be used on this endpoint. 758 * An endpoint must be configured before it can be started. 759 * An endpoint that is already running can not be reconfigured. 760 */ 761 int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep, 762 struct snd_pcm_hw_params *hw_params, 763 struct audioformat *fmt, 764 struct snd_usb_endpoint *sync_ep) 765 { 766 int err; 767 768 if (ep->use_count != 0) { 769 snd_printk(KERN_WARNING "Unable to change format on ep #%x: already in use\n", 770 ep->ep_num); 771 return -EBUSY; 772 } 773 774 /* release old buffers, if any */ 775 release_urbs(ep, 0); 776 777 ep->datainterval = fmt->datainterval; 778 ep->maxpacksize = fmt->maxpacksize; 779 ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX); 780 781 if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL) 782 ep->freqn = get_usb_full_speed_rate(params_rate(hw_params)); 783 else 784 ep->freqn = get_usb_high_speed_rate(params_rate(hw_params)); 785 786 /* calculate the frequency in 16.16 format */ 787 ep->freqm = ep->freqn; 788 ep->freqshift = INT_MIN; 789 790 ep->phase = 0; 791 792 switch (ep->type) { 793 case SND_USB_ENDPOINT_TYPE_DATA: 794 err = data_ep_set_params(ep, hw_params, fmt, sync_ep); 795 break; 796 case SND_USB_ENDPOINT_TYPE_SYNC: 797 err = sync_ep_set_params(ep, hw_params, fmt); 798 break; 799 default: 800 err = -EINVAL; 801 } 802 803 snd_printdd(KERN_DEBUG "Setting params for ep #%x (type %d, %d urbs), ret=%d\n", 804 ep->ep_num, ep->type, ep->nurbs, err); 805 806 return err; 807 } 808 809 /** 810 * snd_usb_endpoint_start: start an snd_usb_endpoint 811 * 812 * @ep: the endpoint to start 813 * 814 * A call to this function will increment the use count of the endpoint. 815 * In case it is not already running, the URBs for this endpoint will be 816 * submitted. Otherwise, this function does nothing. 817 * 818 * Must be balanced to calls of snd_usb_endpoint_stop(). 819 * 820 * Returns an error if the URB submission failed, 0 in all other cases. 821 */ 822 int snd_usb_endpoint_start(struct snd_usb_endpoint *ep) 823 { 824 int err; 825 unsigned int i; 826 827 if (ep->chip->shutdown) 828 return -EBADFD; 829 830 /* already running? */ 831 if (++ep->use_count != 1) 832 return 0; 833 834 if (snd_BUG_ON(!test_bit(EP_FLAG_ACTIVATED, &ep->flags))) 835 return -EINVAL; 836 837 /* just to be sure */ 838 deactivate_urbs(ep, 0, 1); 839 wait_clear_urbs(ep); 840 841 ep->active_mask = 0; 842 ep->unlink_mask = 0; 843 ep->phase = 0; 844 845 /* 846 * If this endpoint has a data endpoint as implicit feedback source, 847 * don't start the urbs here. Instead, mark them all as available, 848 * wait for the record urbs to return and queue the playback urbs 849 * from that context. 850 */ 851 852 set_bit(EP_FLAG_RUNNING, &ep->flags); 853 854 if (snd_usb_endpoint_implict_feedback_sink(ep)) { 855 for (i = 0; i < ep->nurbs; i++) { 856 struct snd_urb_ctx *ctx = ep->urb + i; 857 list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs); 858 } 859 860 return 0; 861 } 862 863 for (i = 0; i < ep->nurbs; i++) { 864 struct urb *urb = ep->urb[i].urb; 865 866 if (snd_BUG_ON(!urb)) 867 goto __error; 868 869 if (usb_pipeout(ep->pipe)) { 870 prepare_outbound_urb_sizes(ep, urb->context); 871 prepare_outbound_urb(ep, urb->context); 872 } else { 873 prepare_inbound_urb(ep, urb->context); 874 } 875 876 err = usb_submit_urb(urb, GFP_ATOMIC); 877 if (err < 0) { 878 snd_printk(KERN_ERR "cannot submit urb %d, error %d: %s\n", 879 i, err, usb_error_string(err)); 880 goto __error; 881 } 882 set_bit(i, &ep->active_mask); 883 } 884 885 return 0; 886 887 __error: 888 clear_bit(EP_FLAG_RUNNING, &ep->flags); 889 ep->use_count--; 890 deactivate_urbs(ep, 0, 0); 891 return -EPIPE; 892 } 893 894 /** 895 * snd_usb_endpoint_stop: stop an snd_usb_endpoint 896 * 897 * @ep: the endpoint to stop (may be NULL) 898 * 899 * A call to this function will decrement the use count of the endpoint. 900 * In case the last user has requested the endpoint stop, the URBs will 901 * actually be deactivated. 902 * 903 * Must be balanced to calls of snd_usb_endpoint_start(). 904 */ 905 void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep, 906 int force, int can_sleep, int wait) 907 { 908 if (!ep) 909 return; 910 911 if (snd_BUG_ON(ep->use_count == 0)) 912 return; 913 914 if (snd_BUG_ON(!test_bit(EP_FLAG_ACTIVATED, &ep->flags))) 915 return; 916 917 if (--ep->use_count == 0) { 918 deactivate_urbs(ep, force, can_sleep); 919 ep->data_subs = NULL; 920 ep->sync_slave = NULL; 921 ep->retire_data_urb = NULL; 922 ep->prepare_data_urb = NULL; 923 924 if (wait) 925 wait_clear_urbs(ep); 926 } 927 } 928 929 /** 930 * snd_usb_endpoint_activate: activate an snd_usb_endpoint 931 * 932 * @ep: the endpoint to activate 933 * 934 * If the endpoint is not currently in use, this functions will select the 935 * correct alternate interface setting for the interface of this endpoint. 936 * 937 * In case of any active users, this functions does nothing. 938 * 939 * Returns an error if usb_set_interface() failed, 0 in all other 940 * cases. 941 */ 942 int snd_usb_endpoint_activate(struct snd_usb_endpoint *ep) 943 { 944 if (ep->use_count != 0) 945 return 0; 946 947 if (!ep->chip->shutdown && 948 !test_and_set_bit(EP_FLAG_ACTIVATED, &ep->flags)) { 949 int ret; 950 951 ret = usb_set_interface(ep->chip->dev, ep->iface, ep->alt_idx); 952 if (ret < 0) { 953 snd_printk(KERN_ERR "%s() usb_set_interface() failed, ret = %d\n", 954 __func__, ret); 955 clear_bit(EP_FLAG_ACTIVATED, &ep->flags); 956 return ret; 957 } 958 959 return 0; 960 } 961 962 return -EBUSY; 963 } 964 965 /** 966 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint 967 * 968 * @ep: the endpoint to deactivate 969 * 970 * If the endpoint is not currently in use, this functions will select the 971 * alternate interface setting 0 for the interface of this endpoint. 972 * 973 * In case of any active users, this functions does nothing. 974 * 975 * Returns an error if usb_set_interface() failed, 0 in all other 976 * cases. 977 */ 978 int snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep) 979 { 980 if (!ep) 981 return -EINVAL; 982 983 if (ep->use_count != 0) 984 return 0; 985 986 if (!ep->chip->shutdown && 987 test_and_clear_bit(EP_FLAG_ACTIVATED, &ep->flags)) { 988 int ret; 989 990 ret = usb_set_interface(ep->chip->dev, ep->iface, 0); 991 if (ret < 0) { 992 snd_printk(KERN_ERR "%s(): usb_set_interface() failed, ret = %d\n", 993 __func__, ret); 994 return ret; 995 } 996 997 return 0; 998 } 999 1000 return -EBUSY; 1001 } 1002 1003 /** 1004 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint 1005 * 1006 * @ep: the list header of the endpoint to free 1007 * 1008 * This function does not care for the endpoint's use count but will tear 1009 * down all the streaming URBs immediately and free all resources. 1010 */ 1011 void snd_usb_endpoint_free(struct list_head *head) 1012 { 1013 struct snd_usb_endpoint *ep; 1014 1015 ep = list_entry(head, struct snd_usb_endpoint, list); 1016 release_urbs(ep, 1); 1017 kfree(ep); 1018 } 1019 1020 /** 1021 * snd_usb_handle_sync_urb: parse an USB sync packet 1022 * 1023 * @ep: the endpoint to handle the packet 1024 * @sender: the sending endpoint 1025 * @urb: the received packet 1026 * 1027 * This function is called from the context of an endpoint that received 1028 * the packet and is used to let another endpoint object handle the payload. 1029 */ 1030 void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep, 1031 struct snd_usb_endpoint *sender, 1032 const struct urb *urb) 1033 { 1034 int shift; 1035 unsigned int f; 1036 unsigned long flags; 1037 1038 snd_BUG_ON(ep == sender); 1039 1040 /* 1041 * In case the endpoint is operating in implicit feedback mode, prepare 1042 * a new outbound URB that has the same layout as the received packet 1043 * and add it to the list of pending urbs. queue_pending_output_urbs() 1044 * will take care of them later. 1045 */ 1046 if (snd_usb_endpoint_implict_feedback_sink(ep) && 1047 ep->use_count != 0) { 1048 1049 /* implicit feedback case */ 1050 int i, bytes = 0; 1051 struct snd_urb_ctx *in_ctx; 1052 struct snd_usb_packet_info *out_packet; 1053 1054 in_ctx = urb->context; 1055 1056 /* Count overall packet size */ 1057 for (i = 0; i < in_ctx->packets; i++) 1058 if (urb->iso_frame_desc[i].status == 0) 1059 bytes += urb->iso_frame_desc[i].actual_length; 1060 1061 /* 1062 * skip empty packets. At least M-Audio's Fast Track Ultra stops 1063 * streaming once it received a 0-byte OUT URB 1064 */ 1065 if (bytes == 0) 1066 return; 1067 1068 spin_lock_irqsave(&ep->lock, flags); 1069 out_packet = ep->next_packet + ep->next_packet_write_pos; 1070 1071 /* 1072 * Iterate through the inbound packet and prepare the lengths 1073 * for the output packet. The OUT packet we are about to send 1074 * will have the same amount of payload bytes than the IN 1075 * packet we just received. 1076 */ 1077 1078 out_packet->packets = in_ctx->packets; 1079 for (i = 0; i < in_ctx->packets; i++) { 1080 if (urb->iso_frame_desc[i].status == 0) 1081 out_packet->packet_size[i] = 1082 urb->iso_frame_desc[i].actual_length / ep->stride; 1083 else 1084 out_packet->packet_size[i] = 0; 1085 } 1086 1087 ep->next_packet_write_pos++; 1088 ep->next_packet_write_pos %= MAX_URBS; 1089 spin_unlock_irqrestore(&ep->lock, flags); 1090 queue_pending_output_urbs(ep); 1091 1092 return; 1093 } 1094 1095 /* 1096 * process after playback sync complete 1097 * 1098 * Full speed devices report feedback values in 10.14 format as samples 1099 * per frame, high speed devices in 16.16 format as samples per 1100 * microframe. 1101 * 1102 * Because the Audio Class 1 spec was written before USB 2.0, many high 1103 * speed devices use a wrong interpretation, some others use an 1104 * entirely different format. 1105 * 1106 * Therefore, we cannot predict what format any particular device uses 1107 * and must detect it automatically. 1108 */ 1109 1110 if (urb->iso_frame_desc[0].status != 0 || 1111 urb->iso_frame_desc[0].actual_length < 3) 1112 return; 1113 1114 f = le32_to_cpup(urb->transfer_buffer); 1115 if (urb->iso_frame_desc[0].actual_length == 3) 1116 f &= 0x00ffffff; 1117 else 1118 f &= 0x0fffffff; 1119 1120 if (f == 0) 1121 return; 1122 1123 if (unlikely(ep->freqshift == INT_MIN)) { 1124 /* 1125 * The first time we see a feedback value, determine its format 1126 * by shifting it left or right until it matches the nominal 1127 * frequency value. This assumes that the feedback does not 1128 * differ from the nominal value more than +50% or -25%. 1129 */ 1130 shift = 0; 1131 while (f < ep->freqn - ep->freqn / 4) { 1132 f <<= 1; 1133 shift++; 1134 } 1135 while (f > ep->freqn + ep->freqn / 2) { 1136 f >>= 1; 1137 shift--; 1138 } 1139 ep->freqshift = shift; 1140 } else if (ep->freqshift >= 0) 1141 f <<= ep->freqshift; 1142 else 1143 f >>= -ep->freqshift; 1144 1145 if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) { 1146 /* 1147 * If the frequency looks valid, set it. 1148 * This value is referred to in prepare_playback_urb(). 1149 */ 1150 spin_lock_irqsave(&ep->lock, flags); 1151 ep->freqm = f; 1152 spin_unlock_irqrestore(&ep->lock, flags); 1153 } else { 1154 /* 1155 * Out of range; maybe the shift value is wrong. 1156 * Reset it so that we autodetect again the next time. 1157 */ 1158 ep->freqshift = INT_MIN; 1159 } 1160 } 1161 1162