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 */
  69static 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 */
  78static 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 */
  86static 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
  96static 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 */
 129int 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 */
 144int snd_usb_endpoint_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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 161static 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
 
 
 
 
 168static 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/*
 181 * Prepare a PLAYBACK urb for submission to the bus.
 182 */
 183static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
 184				 struct snd_urb_ctx *ctx)
 
 185{
 186	int i;
 187	struct urb *urb = ctx->urb;
 188	unsigned char *cp = urb->transfer_buffer;
 
 189
 190	urb->dev = ep->chip->dev; /* we need to set this at each time */
 191
 192	switch (ep->type) {
 193	case SND_USB_ENDPOINT_TYPE_DATA:
 194		if (ep->prepare_data_urb) {
 195			ep->prepare_data_urb(ep->data_subs, urb);
 196		} else {
 197			/* no data provider, so send silence */
 198			unsigned int offs = 0;
 199			for (i = 0; i < ctx->packets; ++i) {
 200				int counts;
 201
 202				if (ctx->packet_size[i])
 203					counts = ctx->packet_size[i];
 204				else
 205					counts = snd_usb_endpoint_next_packet_size(ep);
 206
 207				urb->iso_frame_desc[i].offset = offs * ep->stride;
 208				urb->iso_frame_desc[i].length = counts * ep->stride;
 209				offs += counts;
 210			}
 211
 212			urb->number_of_packets = ctx->packets;
 213			urb->transfer_buffer_length = offs * ep->stride;
 214			memset(urb->transfer_buffer, ep->silence_value,
 215			       offs * ep->stride);
 216		}
 217		break;
 218
 219	case SND_USB_ENDPOINT_TYPE_SYNC:
 220		if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
 221			/*
 222			 * fill the length and offset of each urb descriptor.
 223			 * the fixed 12.13 frequency is passed as 16.16 through the pipe.
 224			 */
 225			urb->iso_frame_desc[0].length = 4;
 226			urb->iso_frame_desc[0].offset = 0;
 227			cp[0] = ep->freqn;
 228			cp[1] = ep->freqn >> 8;
 229			cp[2] = ep->freqn >> 16;
 230			cp[3] = ep->freqn >> 24;
 231		} else {
 232			/*
 233			 * fill the length and offset of each urb descriptor.
 234			 * the fixed 10.14 frequency is passed through the pipe.
 235			 */
 236			urb->iso_frame_desc[0].length = 3;
 237			urb->iso_frame_desc[0].offset = 0;
 238			cp[0] = ep->freqn >> 2;
 239			cp[1] = ep->freqn >> 10;
 240			cp[2] = ep->freqn >> 18;
 241		}
 242
 243		break;
 244	}
 
 245}
 246
 247/*
 248 * Prepare a CAPTURE or SYNC urb for submission to the bus.
 249 */
 250static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep,
 251				       struct snd_urb_ctx *urb_ctx)
 252{
 253	int i, offs;
 254	struct urb *urb = urb_ctx->urb;
 255
 256	urb->dev = ep->chip->dev; /* we need to set this at each time */
 257
 258	switch (ep->type) {
 259	case SND_USB_ENDPOINT_TYPE_DATA:
 260		offs = 0;
 261		for (i = 0; i < urb_ctx->packets; i++) {
 262			urb->iso_frame_desc[i].offset = offs;
 263			urb->iso_frame_desc[i].length = ep->curpacksize;
 264			offs += ep->curpacksize;
 265		}
 266
 267		urb->transfer_buffer_length = offs;
 268		urb->number_of_packets = urb_ctx->packets;
 269		break;
 270
 271	case SND_USB_ENDPOINT_TYPE_SYNC:
 272		urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
 273		urb->iso_frame_desc[0].offset = 0;
 274		break;
 275	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 276}
 277
 278/*
 279 * Send output urbs that have been prepared previously. URBs are dequeued
 280 * from ep->ready_playback_urbs and in case there there aren't any available
 281 * or there are no packets that have been prepared, this function does
 282 * nothing.
 283 *
 284 * The reason why the functionality of sending and preparing URBs is separated
 285 * is that host controllers don't guarantee the order in which they return
 286 * inbound and outbound packets to their submitters.
 287 *
 288 * This function is only used for implicit feedback endpoints. For endpoints
 289 * driven by dedicated sync endpoints, URBs are immediately re-submitted
 290 * from their completion handler.
 291 */
 292static void queue_pending_output_urbs(struct snd_usb_endpoint *ep)
 
 293{
 294	while (test_bit(EP_FLAG_RUNNING, &ep->flags)) {
 
 
 295
 296		unsigned long flags;
 297		struct snd_usb_packet_info *uninitialized_var(packet);
 298		struct snd_urb_ctx *ctx = NULL;
 299		struct urb *urb;
 300		int err, i;
 301
 302		spin_lock_irqsave(&ep->lock, flags);
 303		if (ep->next_packet_read_pos != ep->next_packet_write_pos) {
 304			packet = ep->next_packet + ep->next_packet_read_pos;
 305			ep->next_packet_read_pos++;
 306			ep->next_packet_read_pos %= MAX_URBS;
 307
 308			/* take URB out of FIFO */
 309			if (!list_empty(&ep->ready_playback_urbs))
 310				ctx = list_first_entry(&ep->ready_playback_urbs,
 311					       struct snd_urb_ctx, ready_list);
 
 
 
 312		}
 313		spin_unlock_irqrestore(&ep->lock, flags);
 314
 315		if (ctx == NULL)
 316			return;
 317
 318		list_del_init(&ctx->ready_list);
 319		urb = ctx->urb;
 320
 321		/* copy over the length information */
 322		for (i = 0; i < packet->packets; i++)
 323			ctx->packet_size[i] = packet->packet_size[i];
 
 
 324
 325		/* call the data handler to fill in playback data */
 326		prepare_outbound_urb(ep, ctx);
 
 
 
 
 
 
 
 
 
 327
 328		err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
 329		if (err < 0)
 330			snd_printk(KERN_ERR "Unable to submit urb #%d: %d (urb %p)\n",
 331				   ctx->index, err, ctx->urb);
 
 
 
 332		else
 333			set_bit(ctx->index, &ep->active_mask);
 
 
 
 
 
 
 
 
 
 
 
 
 
 334	}
 
 
 335}
 336
 337/*
 338 * complete callback for urbs
 339 */
 340static void snd_complete_urb(struct urb *urb)
 341{
 342	struct snd_urb_ctx *ctx = urb->context;
 343	struct snd_usb_endpoint *ep = ctx->ep;
 344	int err;
 345
 346	if (unlikely(urb->status == -ENOENT ||		/* unlinked */
 347		     urb->status == -ENODEV ||		/* device removed */
 348		     urb->status == -ECONNRESET ||	/* unlinked */
 349		     urb->status == -ESHUTDOWN ||	/* device disabled */
 350		     ep->chip->shutdown))		/* device disconnected */
 
 
 
 
 
 351		goto exit_clear;
 352
 353	if (usb_pipeout(ep->pipe)) {
 354		retire_outbound_urb(ep, ctx);
 355		/* can be stopped during retire callback */
 356		if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
 357			goto exit_clear;
 358
 359		if (snd_usb_endpoint_implict_feedback_sink(ep)) {
 360			unsigned long flags;
 361
 362			spin_lock_irqsave(&ep->lock, flags);
 363			list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
 364			spin_unlock_irqrestore(&ep->lock, flags);
 365			queue_pending_output_urbs(ep);
 366
 367			goto exit_clear;
 
 368		}
 369
 370		prepare_outbound_urb(ep, ctx);
 
 
 
 
 371	} else {
 372		retire_inbound_urb(ep, ctx);
 373		/* can be stopped during retire callback */
 374		if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
 375			goto exit_clear;
 376
 377		prepare_inbound_urb(ep, ctx);
 378	}
 379
 380	err = usb_submit_urb(urb, GFP_ATOMIC);
 
 
 
 381	if (err == 0)
 382		return;
 383
 384	snd_printk(KERN_ERR "cannot submit urb (err = %d)\n", err);
 385	//snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 
 
 386
 387exit_clear:
 388	clear_bit(ctx->index, &ep->active_mask);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 389}
 390
 
 
 
 391/**
 392 * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
 393 *
 394 * @chip: The chip
 395 * @alts: The USB host interface
 396 * @ep_num: The number of the endpoint to use
 397 * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
 398 * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
 399 *
 400 * If the requested endpoint has not been added to the given chip before,
 401 * a new instance is created. Otherwise, a pointer to the previoulsy
 402 * created instance is returned. In case of any error, NULL is returned.
 
 
 
 
 403 *
 404 * New endpoints will be added to chip->ep_list and must be freed by
 405 * calling snd_usb_endpoint_free().
 406 */
 407struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
 408					      struct usb_host_interface *alts,
 409					      int ep_num, int direction, int type)
 410{
 411	struct list_head *p;
 412	struct snd_usb_endpoint *ep;
 413	int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK;
 414
 415	mutex_lock(&chip->mutex);
 416
 417	list_for_each(p, &chip->ep_list) {
 418		ep = list_entry(p, struct snd_usb_endpoint, list);
 419		if (ep->ep_num == ep_num &&
 420		    ep->iface == alts->desc.bInterfaceNumber &&
 421		    ep->alt_idx == alts->desc.bAlternateSetting) {
 422			snd_printdd(KERN_DEBUG "Re-using EP %x in iface %d,%d @%p\n",
 423					ep_num, ep->iface, ep->alt_idx, ep);
 424			goto __exit_unlock;
 425		}
 426	}
 427
 428	snd_printdd(KERN_DEBUG "Creating new %s %s endpoint #%x\n",
 429		    is_playback ? "playback" : "capture",
 430		    type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync",
 431		    ep_num);
 432
 
 
 
 433	ep = kzalloc(sizeof(*ep), GFP_KERNEL);
 434	if (!ep)
 435		goto __exit_unlock;
 436
 437	ep->chip = chip;
 438	spin_lock_init(&ep->lock);
 439	ep->type = type;
 440	ep->ep_num = ep_num;
 441	ep->iface = alts->desc.bInterfaceNumber;
 442	ep->alt_idx = alts->desc.bAlternateSetting;
 443	INIT_LIST_HEAD(&ep->ready_playback_urbs);
 444	ep_num &= USB_ENDPOINT_NUMBER_MASK;
 445
 
 
 446	if (is_playback)
 447		ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
 448	else
 449		ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
 450
 451	if (type == SND_USB_ENDPOINT_TYPE_SYNC) {
 452		if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
 453		    get_endpoint(alts, 1)->bRefresh >= 1 &&
 454		    get_endpoint(alts, 1)->bRefresh <= 9)
 455			ep->syncinterval = get_endpoint(alts, 1)->bRefresh;
 456		else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
 457			ep->syncinterval = 1;
 458		else if (get_endpoint(alts, 1)->bInterval >= 1 &&
 459			 get_endpoint(alts, 1)->bInterval <= 16)
 460			ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1;
 461		else
 462			ep->syncinterval = 3;
 463
 464		ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize);
 465	}
 
 
 
 
 466
 467	list_add_tail(&ep->list, &chip->ep_list);
 
 
 
 
 
 
 
 
 
 
 
 
 
 468
 469__exit_unlock:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 470	mutex_unlock(&chip->mutex);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 471
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 472	return ep;
 473}
 474
 475/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 476 *  wait until all urbs are processed.
 477 */
 478static int wait_clear_urbs(struct snd_usb_endpoint *ep)
 479{
 480	unsigned long end_time = jiffies + msecs_to_jiffies(1000);
 481	unsigned int i;
 482	int alive;
 483
 484	do {
 485		alive = 0;
 486		for (i = 0; i < ep->nurbs; i++)
 487			if (test_bit(i, &ep->active_mask))
 488				alive++;
 489
 
 
 490		if (!alive)
 491			break;
 492
 493		schedule_timeout_uninterruptible(1);
 494	} while (time_before(jiffies, end_time));
 495
 496	if (alive)
 497		snd_printk(KERN_ERR "timeout: still %d active urbs on EP #%x\n",
 498					alive, ep->ep_num);
 
 
 
 
 
 
 499
 500	return 0;
 501}
 502
 
 
 
 
 
 
 
 
 
 503/*
 504 * unlink active urbs.
 
 
 505 */
 506static int deactivate_urbs(struct snd_usb_endpoint *ep, int force, int can_sleep)
 507{
 508	unsigned int i;
 509	int async;
 510
 511	if (!force && ep->chip->shutdown) /* to be sure... */
 512		return -EBADFD;
 513
 514	async = !can_sleep && ep->chip->async_unlink;
 
 515
 516	clear_bit(EP_FLAG_RUNNING, &ep->flags);
 
 517
 
 518	INIT_LIST_HEAD(&ep->ready_playback_urbs);
 519	ep->next_packet_read_pos = 0;
 520	ep->next_packet_write_pos = 0;
 
 521
 522	if (!async && in_interrupt())
 523		return 0;
 524
 525	for (i = 0; i < ep->nurbs; i++) {
 526		if (test_bit(i, &ep->active_mask)) {
 527			if (!test_and_set_bit(i, &ep->unlink_mask)) {
 528				struct urb *u = ep->urb[i].urb;
 529				if (async)
 530					usb_unlink_urb(u);
 531				else
 532					usb_kill_urb(u);
 533			}
 534		}
 535	}
 536
 537	return 0;
 538}
 539
 540/*
 541 * release an endpoint's urbs
 542 */
 543static void release_urbs(struct snd_usb_endpoint *ep, int force)
 544{
 545	int i;
 546
 547	/* route incoming urbs to nirvana */
 548	ep->retire_data_urb = NULL;
 549	ep->prepare_data_urb = NULL;
 
 
 
 
 550
 551	/* stop urbs */
 552	deactivate_urbs(ep, force, 1);
 553	wait_clear_urbs(ep);
 554
 555	for (i = 0; i < ep->nurbs; i++)
 556		release_urb_ctx(&ep->urb[i]);
 557
 558	if (ep->syncbuf)
 559		usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
 560				  ep->syncbuf, ep->sync_dma);
 561
 562	ep->syncbuf = NULL;
 563	ep->nurbs = 0;
 
 564}
 565
 566/*
 567 * configure a data endpoint
 568 */
 569static int data_ep_set_params(struct snd_usb_endpoint *ep,
 570			      struct snd_pcm_hw_params *hw_params,
 571			      struct audioformat *fmt,
 572			      struct snd_usb_endpoint *sync_ep)
 573{
 574	unsigned int maxsize, i, urb_packs, total_packs, packs_per_ms;
 575	int period_bytes = params_period_bytes(hw_params);
 576	int format = params_format(hw_params);
 577	int is_playback = usb_pipeout(ep->pipe);
 578	int frame_bits = snd_pcm_format_physical_width(params_format(hw_params)) *
 579							params_channels(hw_params);
 
 
 
 
 
 
 
 
 
 
 
 580
 581	ep->datainterval = fmt->datainterval;
 582	ep->stride = frame_bits >> 3;
 583	ep->silence_value = format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0;
 584
 585	/* calculate max. frequency */
 586	if (ep->maxpacksize) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 587		/* whatever fits into a max. size packet */
 588		maxsize = ep->maxpacksize;
 589		ep->freqmax = (maxsize / (frame_bits >> 3))
 
 
 
 
 590				<< (16 - ep->datainterval);
 591	} else {
 592		/* no max. packet size: just take 25% higher than nominal */
 593		ep->freqmax = ep->freqn + (ep->freqn >> 2);
 594		maxsize = ((ep->freqmax + 0xffff) * (frame_bits >> 3))
 595				>> (16 - ep->datainterval);
 596	}
 597
 598	if (ep->fill_max)
 599		ep->curpacksize = ep->maxpacksize;
 600	else
 601		ep->curpacksize = maxsize;
 602
 603	if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL)
 604		packs_per_ms = 8 >> ep->datainterval;
 605	else
 606		packs_per_ms = 1;
 607
 608	if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) {
 609		urb_packs = max(ep->chip->nrpacks, 1);
 610		urb_packs = min(urb_packs, (unsigned int) MAX_PACKS);
 611	} else {
 612		urb_packs = 1;
 
 613	}
 
 
 
 
 614
 615	urb_packs *= packs_per_ms;
 
 
 
 
 
 
 
 
 616
 617	if (sync_ep && !snd_usb_endpoint_implict_feedback_sink(ep))
 618		urb_packs = min(urb_packs, 1U << sync_ep->syncinterval);
 
 
 
 619
 620	/* decide how many packets to be used */
 621	if (is_playback && !snd_usb_endpoint_implict_feedback_sink(ep)) {
 622		unsigned int minsize, maxpacks;
 
 
 
 
 623		/* determine how small a packet can be */
 624		minsize = (ep->freqn >> (16 - ep->datainterval))
 625			  * (frame_bits >> 3);
 626		/* with sync from device, assume it can be 12% lower */
 627		if (sync_ep)
 628			minsize -= minsize >> 3;
 629		minsize = max(minsize, 1u);
 630		total_packs = (period_bytes + minsize - 1) / minsize;
 631		/* we need at least two URBs for queueing */
 632		if (total_packs < 2) {
 633			total_packs = 2;
 634		} else {
 635			/* and we don't want too long a queue either */
 636			maxpacks = max(MAX_QUEUE * packs_per_ms, urb_packs * 2);
 637			total_packs = min(total_packs, maxpacks);
 638		}
 639	} else {
 640		while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
 641			urb_packs >>= 1;
 642		total_packs = MAX_URBS * urb_packs;
 643	}
 644
 645	ep->nurbs = (total_packs + urb_packs - 1) / urb_packs;
 646	if (ep->nurbs > MAX_URBS) {
 647		/* too much... */
 648		ep->nurbs = MAX_URBS;
 649		total_packs = MAX_URBS * urb_packs;
 650	} else if (ep->nurbs < 2) {
 651		/* too little - we need at least two packets
 652		 * to ensure contiguous playback/capture
 653		 */
 654		ep->nurbs = 2;
 
 
 
 
 
 
 
 655	}
 656
 657	/* allocate and initialize data urbs */
 658	for (i = 0; i < ep->nurbs; i++) {
 659		struct snd_urb_ctx *u = &ep->urb[i];
 660		u->index = i;
 661		u->ep = ep;
 662		u->packets = (i + 1) * total_packs / ep->nurbs
 663			- i * total_packs / ep->nurbs;
 664		u->buffer_size = maxsize * u->packets;
 665
 666		if (fmt->fmt_type == UAC_FORMAT_TYPE_II)
 667			u->packets++; /* for transfer delimiter */
 668		u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
 669		if (!u->urb)
 670			goto out_of_memory;
 671
 672		u->urb->transfer_buffer =
 673			usb_alloc_coherent(ep->chip->dev, u->buffer_size,
 674					   GFP_KERNEL, &u->urb->transfer_dma);
 675		if (!u->urb->transfer_buffer)
 676			goto out_of_memory;
 677		u->urb->pipe = ep->pipe;
 678		u->urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
 679		u->urb->interval = 1 << ep->datainterval;
 680		u->urb->context = u;
 681		u->urb->complete = snd_complete_urb;
 682		INIT_LIST_HEAD(&u->ready_list);
 683	}
 684
 685	return 0;
 686
 687out_of_memory:
 688	release_urbs(ep, 0);
 689	return -ENOMEM;
 690}
 691
 692/*
 693 * configure a sync endpoint
 694 */
 695static int sync_ep_set_params(struct snd_usb_endpoint *ep,
 696			      struct snd_pcm_hw_params *hw_params,
 697			      struct audioformat *fmt)
 698{
 
 699	int i;
 700
 701	ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4,
 
 
 
 702					 GFP_KERNEL, &ep->sync_dma);
 703	if (!ep->syncbuf)
 704		return -ENOMEM;
 705
 
 706	for (i = 0; i < SYNC_URBS; i++) {
 707		struct snd_urb_ctx *u = &ep->urb[i];
 708		u->index = i;
 709		u->ep = ep;
 710		u->packets = 1;
 711		u->urb = usb_alloc_urb(1, GFP_KERNEL);
 712		if (!u->urb)
 713			goto out_of_memory;
 714		u->urb->transfer_buffer = ep->syncbuf + i * 4;
 715		u->urb->transfer_dma = ep->sync_dma + i * 4;
 716		u->urb->transfer_buffer_length = 4;
 717		u->urb->pipe = ep->pipe;
 718		u->urb->transfer_flags = URB_ISO_ASAP |
 719					 URB_NO_TRANSFER_DMA_MAP;
 720		u->urb->number_of_packets = 1;
 721		u->urb->interval = 1 << ep->syncinterval;
 722		u->urb->context = u;
 723		u->urb->complete = snd_complete_urb;
 724	}
 725
 726	ep->nurbs = SYNC_URBS;
 727
 728	return 0;
 729
 730out_of_memory:
 731	release_urbs(ep, 0);
 732	return -ENOMEM;
 733}
 734
 735/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 736 * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
 737 *
 738 * @ep: the snd_usb_endpoint to configure
 739 * @hw_params: the hardware parameters
 740 * @fmt: the USB audio format information
 741 * @sync_ep: the sync endpoint to use, if any
 742 *
 743 * Determine the number of URBs to be used on this endpoint.
 744 * An endpoint must be configured before it can be started.
 745 * An endpoint that is already running can not be reconfigured.
 746 */
 747int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
 748				struct snd_pcm_hw_params *hw_params,
 749				struct audioformat *fmt,
 750				struct snd_usb_endpoint *sync_ep)
 751{
 752	int err;
 
 753
 754	if (ep->use_count != 0) {
 755		snd_printk(KERN_WARNING "Unable to change format on ep #%x: already in use\n",
 756			   ep->ep_num);
 757		return -EBUSY;
 758	}
 759
 760	/* release old buffers, if any */
 761	release_urbs(ep, 0);
 
 
 762
 763	ep->datainterval = fmt->datainterval;
 764	ep->maxpacksize = fmt->maxpacksize;
 765	ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
 766
 767	if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL)
 768		ep->freqn = get_usb_full_speed_rate(params_rate(hw_params));
 769	else
 770		ep->freqn = get_usb_high_speed_rate(params_rate(hw_params));
 
 
 
 
 
 
 
 771
 772	/* calculate the frequency in 16.16 format */
 773	ep->freqm = ep->freqn;
 774	ep->freqshift = INT_MIN;
 775
 776	ep->phase = 0;
 777
 778	switch (ep->type) {
 779	case  SND_USB_ENDPOINT_TYPE_DATA:
 780		err = data_ep_set_params(ep, hw_params, fmt, sync_ep);
 781		break;
 782	case  SND_USB_ENDPOINT_TYPE_SYNC:
 783		err = sync_ep_set_params(ep, hw_params, fmt);
 784		break;
 785	default:
 786		err = -EINVAL;
 787	}
 788
 789	snd_printdd(KERN_DEBUG "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
 790		   ep->ep_num, ep->type, ep->nurbs, err);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 791
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 792	return err;
 793}
 794
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 795/**
 796 * snd_usb_endpoint_start: start an snd_usb_endpoint
 797 *
 798 * @ep:		the endpoint to start
 799 * @can_sleep:	flag indicating whether the operation is executed in
 800 * 		non-atomic context
 801 *
 802 * A call to this function will increment the use count of the endpoint.
 803 * In case it is not already running, the URBs for this endpoint will be
 804 * submitted. Otherwise, this function does nothing.
 805 *
 806 * Must be balanced to calls of snd_usb_endpoint_stop().
 807 *
 808 * Returns an error if the URB submission failed, 0 in all other cases.
 809 */
 810int snd_usb_endpoint_start(struct snd_usb_endpoint *ep, int can_sleep)
 811{
 
 812	int err;
 813	unsigned int i;
 814
 815	if (ep->chip->shutdown)
 816		return -EBADFD;
 817
 
 
 
 
 
 
 
 818	/* already running? */
 819	if (++ep->use_count != 1)
 820		return 0;
 821
 822	/* just to be sure */
 823	deactivate_urbs(ep, 0, can_sleep);
 824	if (can_sleep)
 825		wait_clear_urbs(ep);
 826
 827	ep->active_mask = 0;
 828	ep->unlink_mask = 0;
 829	ep->phase = 0;
 
 
 
 830
 831	/*
 832	 * If this endpoint has a data endpoint as implicit feedback source,
 833	 * don't start the urbs here. Instead, mark them all as available,
 834	 * wait for the record urbs to return and queue the playback urbs
 835	 * from that context.
 836	 */
 837
 838	set_bit(EP_FLAG_RUNNING, &ep->flags);
 839
 840	if (snd_usb_endpoint_implict_feedback_sink(ep)) {
 841		for (i = 0; i < ep->nurbs; i++) {
 842			struct snd_urb_ctx *ctx = ep->urb + i;
 843			list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
 844		}
 845
 846		return 0;
 
 
 
 
 847	}
 848
 849	for (i = 0; i < ep->nurbs; i++) {
 850		struct urb *urb = ep->urb[i].urb;
 851
 852		if (snd_BUG_ON(!urb))
 853			goto __error;
 854
 855		if (usb_pipeout(ep->pipe)) {
 856			prepare_outbound_urb(ep, urb->context);
 857		} else {
 858			prepare_inbound_urb(ep, urb->context);
 
 
 
 
 
 
 
 
 859		}
 860
 861		err = usb_submit_urb(urb, GFP_ATOMIC);
 
 
 
 862		if (err < 0) {
 863			snd_printk(KERN_ERR "cannot submit urb %d, error %d: %s\n",
 864				   i, err, usb_error_string(err));
 
 
 865			goto __error;
 866		}
 867		set_bit(i, &ep->active_mask);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 868	}
 869
 870	return 0;
 871
 872__error:
 873	clear_bit(EP_FLAG_RUNNING, &ep->flags);
 874	ep->use_count--;
 875	deactivate_urbs(ep, 0, 0);
 876	return -EPIPE;
 877}
 878
 879/**
 880 * snd_usb_endpoint_stop: stop an snd_usb_endpoint
 881 *
 882 * @ep: the endpoint to stop (may be NULL)
 
 883 *
 884 * A call to this function will decrement the use count of the endpoint.
 885 * In case the last user has requested the endpoint stop, the URBs will
 886 * actually be deactivated.
 887 *
 888 * Must be balanced to calls of snd_usb_endpoint_start().
 
 
 
 889 */
 890void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep,
 891			   int force, int can_sleep, int wait)
 892{
 893	if (!ep)
 894		return;
 895
 896	if (snd_BUG_ON(ep->use_count == 0))
 897		return;
 
 898
 899	if (--ep->use_count == 0) {
 900		deactivate_urbs(ep, force, can_sleep);
 901		ep->data_subs = NULL;
 902		ep->sync_slave = NULL;
 903		ep->retire_data_urb = NULL;
 904		ep->prepare_data_urb = NULL;
 905
 906		if (wait)
 907			wait_clear_urbs(ep);
 
 
 
 
 
 
 
 
 
 
 
 908	}
 909}
 910
 911/**
 912 * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
 913 *
 914 * @ep: the endpoint to deactivate
 915 *
 916 * If the endpoint is not currently in use, this functions will select the
 917 * alternate interface setting 0 for the interface of this endpoint.
 918 *
 919 * In case of any active users, this functions does nothing.
 920 *
 921 * Returns an error if usb_set_interface() failed, 0 in all other
 922 * cases.
 923 */
 924int snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep)
 925{
 926	if (!ep)
 927		return -EINVAL;
 928
 929	deactivate_urbs(ep, 1, 1);
 930	wait_clear_urbs(ep);
 931
 932	if (ep->use_count != 0)
 933		return 0;
 934
 935	clear_bit(EP_FLAG_ACTIVATED, &ep->flags);
 936
 937	return 0;
 938}
 939
 940/**
 941 * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
 942 *
 943 * @ep: the list header of the endpoint to free
 944 *
 945 * This function does not care for the endpoint's use count but will tear
 946 * down all the streaming URBs immediately and free all resources.
 947 */
 948void snd_usb_endpoint_free(struct list_head *head)
 949{
 950	struct snd_usb_endpoint *ep;
 
 
 
 
 
 951
 952	ep = list_entry(head, struct snd_usb_endpoint, list);
 953	release_urbs(ep, 1);
 954	kfree(ep);
 
 
 955}
 956
 957/**
 958 * snd_usb_handle_sync_urb: parse an USB sync packet
 959 *
 960 * @ep: the endpoint to handle the packet
 961 * @sender: the sending endpoint
 962 * @urb: the received packet
 963 *
 964 * This function is called from the context of an endpoint that received
 965 * the packet and is used to let another endpoint object handle the payload.
 966 */
 967void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
 968			     struct snd_usb_endpoint *sender,
 969			     const struct urb *urb)
 970{
 971	int shift;
 972	unsigned int f;
 973	unsigned long flags;
 974
 975	snd_BUG_ON(ep == sender);
 976
 977	/*
 978	 * In case the endpoint is operating in implicit feedback mode, prepare
 979	 * a new outbound URB that has the same layout as the received packet
 980	 * and add it to the list of pending urbs. queue_pending_output_urbs()
 981	 * will take care of them later.
 982	 */
 983	if (snd_usb_endpoint_implict_feedback_sink(ep) &&
 984	    ep->use_count != 0) {
 985
 986		/* implicit feedback case */
 987		int i, bytes = 0;
 988		struct snd_urb_ctx *in_ctx;
 989		struct snd_usb_packet_info *out_packet;
 990
 991		in_ctx = urb->context;
 992
 993		/* Count overall packet size */
 994		for (i = 0; i < in_ctx->packets; i++)
 995			if (urb->iso_frame_desc[i].status == 0)
 996				bytes += urb->iso_frame_desc[i].actual_length;
 997
 998		/*
 999		 * skip empty packets. At least M-Audio's Fast Track Ultra stops
1000		 * streaming once it received a 0-byte OUT URB
1001		 */
1002		if (bytes == 0)
1003			return;
1004
1005		spin_lock_irqsave(&ep->lock, flags);
1006		out_packet = ep->next_packet + ep->next_packet_write_pos;
 
 
 
 
 
 
 
 
 
1007
1008		/*
1009		 * Iterate through the inbound packet and prepare the lengths
1010		 * for the output packet. The OUT packet we are about to send
1011		 * will have the same amount of payload bytes than the IN
1012		 * packet we just received.
 
 
 
1013		 */
1014
1015		out_packet->packets = in_ctx->packets;
1016		for (i = 0; i < in_ctx->packets; i++) {
1017			if (urb->iso_frame_desc[i].status == 0)
1018				out_packet->packet_size[i] =
1019					urb->iso_frame_desc[i].actual_length / ep->stride;
1020			else
1021				out_packet->packet_size[i] = 0;
1022		}
1023
1024		ep->next_packet_write_pos++;
1025		ep->next_packet_write_pos %= MAX_URBS;
1026		spin_unlock_irqrestore(&ep->lock, flags);
1027		queue_pending_output_urbs(ep);
1028
1029		return;
1030	}
1031
1032	/*
1033	 * process after playback sync complete
1034	 *
1035	 * Full speed devices report feedback values in 10.14 format as samples
1036	 * per frame, high speed devices in 16.16 format as samples per
1037	 * microframe.
1038	 *
1039	 * Because the Audio Class 1 spec was written before USB 2.0, many high
1040	 * speed devices use a wrong interpretation, some others use an
1041	 * entirely different format.
1042	 *
1043	 * Therefore, we cannot predict what format any particular device uses
1044	 * and must detect it automatically.
1045	 */
1046
1047	if (urb->iso_frame_desc[0].status != 0 ||
1048	    urb->iso_frame_desc[0].actual_length < 3)
1049		return;
1050
1051	f = le32_to_cpup(urb->transfer_buffer);
1052	if (urb->iso_frame_desc[0].actual_length == 3)
1053		f &= 0x00ffffff;
1054	else
1055		f &= 0x0fffffff;
1056
1057	if (f == 0)
1058		return;
1059
1060	if (unlikely(ep->freqshift == INT_MIN)) {
 
 
 
 
 
 
 
 
 
 
1061		/*
1062		 * The first time we see a feedback value, determine its format
1063		 * by shifting it left or right until it matches the nominal
1064		 * frequency value.  This assumes that the feedback does not
1065		 * differ from the nominal value more than +50% or -25%.
1066		 */
1067		shift = 0;
1068		while (f < ep->freqn - ep->freqn / 4) {
1069			f <<= 1;
1070			shift++;
1071		}
1072		while (f > ep->freqn + ep->freqn / 2) {
1073			f >>= 1;
1074			shift--;
1075		}
1076		ep->freqshift = shift;
1077	} else if (ep->freqshift >= 0)
1078		f <<= ep->freqshift;
1079	else
1080		f >>= -ep->freqshift;
1081
1082	if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
1083		/*
1084		 * If the frequency looks valid, set it.
1085		 * This value is referred to in prepare_playback_urb().
1086		 */
1087		spin_lock_irqsave(&ep->lock, flags);
1088		ep->freqm = f;
1089		spin_unlock_irqrestore(&ep->lock, flags);
1090	} else {
1091		/*
1092		 * Out of range; maybe the shift value is wrong.
1093		 * Reset it so that we autodetect again the next time.
1094		 */
1095		ep->freqshift = INT_MIN;
1096	}
1097}
1098