target/linux/s3c24xx/files-2.6.30/drivers/ar6000/htc/htc_recv.c

   1 /*
   2  *
   3  * Copyright (c) 2007 Atheros Communications Inc.
   4  * All rights reserved.
   5  *
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License version 2 as
   9  *  published by the Free Software Foundation;
  10  *
  11  *  Software distributed under the License is distributed on an "AS
  12  *  IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
  13  *  implied. See the License for the specific language governing
  14  *  rights and limitations under the License.
  15  *
  16  *
  17  *
  18  */
  19
  20 #include "htc_internal.h"
  21
  22 #define HTCIssueRecv(t, p) \
  23     DevRecvPacket(&(t)->Device,  \
  24                   (p),          \
  25                   (p)->ActualLength)
  26
  27 #define DO_RCV_COMPLETION(t,p,e)            \
  28 {                                           \
  29     if ((p)->ActualLength > 0) {            \
  30         AR_DEBUG_PRINTF(ATH_DEBUG_RECV, (" completing packet 0x%X (%d bytes) on ep : %d \n", \
  31             (A_UINT32)(p), (p)->ActualLength, (p)->Endpoint));  \
  32         (e)->EpCallBacks.EpRecv((e)->EpCallBacks.pContext,      \
  33                                 (p));                           \
  34     } else {                                                    \
  35         AR_DEBUG_PRINTF(ATH_DEBUG_RECV, (" recycling empty packet \n"));  \
  36         HTC_RECYCLE_RX_PKT((t), (p));                           \
  37     }                                                           \
  38 }
  39
  40 #ifdef HTC_EP_STAT_PROFILING
  41 #define HTC_RX_STAT_PROFILE(t,ep,lookAhead)            \
  42 {                                                      \
  43     LOCK_HTC_RX((t));                                  \
  44     INC_HTC_EP_STAT((ep), RxReceived, 1);              \
  45     if ((lookAhead) != 0) {                            \
  46         INC_HTC_EP_STAT((ep), RxLookAheads, 1);        \
  47     }                                                  \
  48     UNLOCK_HTC_RX((t));                                \
  49 }
  50 #else
  51 #define HTC_RX_STAT_PROFILE(t,ep,lookAhead)
  52 #endif
  53
  54 static INLINE A_STATUS HTCProcessTrailer(HTC_TARGET *target,
  55                                          A_UINT8    *pBuffer,
  56                                          int         Length,
  57                                          A_UINT32   *pNextLookAhead,
  58                                          HTC_ENDPOINT_ID FromEndpoint)
  59 {
  60     HTC_RECORD_HDR          *pRecord;
  61     A_UINT8                 *pRecordBuf;
  62     HTC_LOOKAHEAD_REPORT    *pLookAhead;
  63     A_UINT8                 *pOrigBuffer;
  64     int                     origLength;
  65     A_STATUS                status;
  66
  67     AR_DEBUG_PRINTF(ATH_DEBUG_RECV, ("+HTCProcessTrailer (length:%d) \n", Length));
  68
  69     if (AR_DEBUG_LVL_CHECK(ATH_DEBUG_RECV)) {
  70         AR_DEBUG_PRINTBUF(pBuffer,Length,"Recv Trailer");
  71     }
  72
  73     pOrigBuffer = pBuffer;
  74     origLength = Length;
  75     status = A_OK;
  76
  77     while (Length > 0) {
  78
  79         if (Length < sizeof(HTC_RECORD_HDR)) {
  80             status = A_EPROTO;
  81             break;
  82         }
  83             /* these are byte aligned structs */
  84         pRecord = (HTC_RECORD_HDR *)pBuffer;
  85         Length -= sizeof(HTC_RECORD_HDR);
  86         pBuffer += sizeof(HTC_RECORD_HDR);
  87
  88         if (pRecord->Length > Length) {
  89                 /* no room left in buffer for record */
  90             AR_DEBUG_PRINTF(ATH_DEBUG_ERR,
  91                 (" invalid record length: %d (id:%d) buffer has: %d bytes left \n",
  92                         pRecord->Length, pRecord->RecordID, Length));
  93             status = A_EPROTO;
  94             break;
  95         }
  96             /* start of record follows the header */
  97         pRecordBuf = pBuffer;
  98
  99         switch (pRecord->RecordID) {
 100             case HTC_RECORD_CREDITS:
 101                 AR_DEBUG_ASSERT(pRecord->Length >= sizeof(HTC_CREDIT_REPORT));
 102                 HTCProcessCreditRpt(target,
 103                                     (HTC_CREDIT_REPORT *)pRecordBuf,
 104                                     pRecord->Length / (sizeof(HTC_CREDIT_REPORT)),
 105                                     FromEndpoint);
 106                 break;
 107             case HTC_RECORD_LOOKAHEAD:
 108                 AR_DEBUG_ASSERT(pRecord->Length >= sizeof(HTC_LOOKAHEAD_REPORT));
 109                 pLookAhead = (HTC_LOOKAHEAD_REPORT *)pRecordBuf;
 110                 if ((pLookAhead->PreValid == ((~pLookAhead->PostValid) & 0xFF)) &&
 111                     (pNextLookAhead != NULL)) {
 112
 113                     AR_DEBUG_PRINTF(ATH_DEBUG_RECV,
 114                                 (" LookAhead Report Found (pre valid:0x%X, post valid:0x%X) \n",
 115                                 pLookAhead->PreValid,
 116                                 pLookAhead->PostValid));
 117
 118                         /* look ahead bytes are valid, copy them over */
 119                     ((A_UINT8 *)pNextLookAhead)[0] = pLookAhead->LookAhead[0];
 120                     ((A_UINT8 *)pNextLookAhead)[1] = pLookAhead->LookAhead[1];
 121                     ((A_UINT8 *)pNextLookAhead)[2] = pLookAhead->LookAhead[2];
 122                     ((A_UINT8 *)pNextLookAhead)[3] = pLookAhead->LookAhead[3];
 123
 124                     if (AR_DEBUG_LVL_CHECK(ATH_DEBUG_RECV)) {
 125                         DebugDumpBytes((A_UINT8 *)pNextLookAhead,4,"Next Look Ahead");
 126                     }
 127                 }
 128                 break;
 129             default:
 130                 AR_DEBUG_PRINTF(ATH_DEBUG_ERR, (" unhandled record: id:%d length:%d \n",
 131                         pRecord->RecordID, pRecord->Length));
 132                 break;
 133         }
 134
 135         if (A_FAILED(status)) {
 136             break;
 137         }
 138
 139             /* advance buffer past this record for next time around */
 140         pBuffer += pRecord->Length;
 141         Length -= pRecord->Length;
 142     }
 143
 144     if (A_FAILED(status)) {
 145         DebugDumpBytes(pOrigBuffer,origLength,"BAD Recv Trailer");
 146     }
 147
 148     AR_DEBUG_PRINTF(ATH_DEBUG_RECV, ("-HTCProcessTrailer \n"));
 149     return status;
 150
 151 }
 152
 153 /* process a received message (i.e. strip off header, process any trailer data)
 154  * note : locks must be released when this function is called */
 155 static A_STATUS HTCProcessRecvHeader(HTC_TARGET *target, HTC_PACKET *pPacket, A_UINT32 *pNextLookAhead)
 156 {
 157     A_UINT8   temp;
 158     A_UINT8   *pBuf;
 159     A_STATUS  status = A_OK;
 160     A_UINT16  payloadLen;
 161     A_UINT32  lookAhead;
 162
 163     pBuf = pPacket->pBuffer;
 164
 165     AR_DEBUG_PRINTF(ATH_DEBUG_RECV, ("+HTCProcessRecvHeader \n"));
 166
 167     if (AR_DEBUG_LVL_CHECK(ATH_DEBUG_RECV)) {
 168         AR_DEBUG_PRINTBUF(pBuf,pPacket->ActualLength,"HTC Recv PKT");
 169     }
 170
 171     do {
 172         /* note, we cannot assume the alignment of pBuffer, so we use the safe macros to
 173          * retrieve 16 bit fields */
 174         payloadLen = A_GET_UINT16_FIELD(pBuf, HTC_FRAME_HDR, PayloadLen);
 175
 176         ((A_UINT8 *)&lookAhead)[0] = pBuf[0];
 177         ((A_UINT8 *)&lookAhead)[1] = pBuf[1];
 178         ((A_UINT8 *)&lookAhead)[2] = pBuf[2];
 179         ((A_UINT8 *)&lookAhead)[3] = pBuf[3];
 180
 181         if (lookAhead != pPacket->HTCReserved) {
 182             /* somehow the lookahead that gave us the full read length did not
 183              * reflect the actual header in the pending message */
 184              AR_DEBUG_PRINTF(ATH_DEBUG_ERR,
 185                     ("HTCProcessRecvHeader, lookahead mismatch! \n"));
 186              DebugDumpBytes((A_UINT8 *)&pPacket->HTCReserved,4,"Expected Message LookAhead");
 187              DebugDumpBytes(pBuf,sizeof(HTC_FRAME_HDR),"Current Frame Header");
 188 #ifdef HTC_CAPTURE_LAST_FRAME
 189             DebugDumpBytes((A_UINT8 *)&target->LastFrameHdr,sizeof(HTC_FRAME_HDR),"Last Frame Header");
 190             if (target->LastTrailerLength != 0) {
 191                 DebugDumpBytes(target->LastTrailer,
 192                                target->LastTrailerLength,
 193                                "Last trailer");
 194             }
 195 #endif
 196             status = A_EPROTO;
 197             break;
 198         }
 199
 200             /* get flags */
 201         temp = A_GET_UINT8_FIELD(pBuf, HTC_FRAME_HDR, Flags);
 202
 203         if (temp & HTC_FLAGS_RECV_TRAILER) {
 204             /* this packet has a trailer */
 205
 206                 /* extract the trailer length in control byte 0 */
 207             temp = A_GET_UINT8_FIELD(pBuf, HTC_FRAME_HDR, ControlBytes[0]);
 208
 209             if ((temp < sizeof(HTC_RECORD_HDR)) || (temp > payloadLen)) {
 210                 AR_DEBUG_PRINTF(ATH_DEBUG_ERR,
 211                     ("HTCProcessRecvHeader, invalid header (payloadlength should be :%d, CB[0] is:%d) \n",
 212                         payloadLen, temp));
 213                 status = A_EPROTO;
 214                 break;
 215             }
 216
 217                 /* process trailer data that follows HDR + application payload */
 218             status = HTCProcessTrailer(target,
 219                                        (pBuf + HTC_HDR_LENGTH + payloadLen - temp),
 220                                        temp,
 221                                        pNextLookAhead,
 222                                        pPacket->Endpoint);
 223
 224             if (A_FAILED(status)) {
 225                 break;
 226             }
 227
 228 #ifdef HTC_CAPTURE_LAST_FRAME
 229             A_MEMCPY(target->LastTrailer, (pBuf + HTC_HDR_LENGTH + payloadLen - temp), temp);
 230             target->LastTrailerLength = temp;
 231 #endif
 232                 /* trim length by trailer bytes */
 233             pPacket->ActualLength -= temp;
 234         }
 235 #ifdef HTC_CAPTURE_LAST_FRAME
 236          else {
 237             target->LastTrailerLength = 0;
 238         }
 239 #endif
 240
 241             /* if we get to this point, the packet is good */
 242             /* remove header and adjust length */
 243         pPacket->pBuffer += HTC_HDR_LENGTH;
 244         pPacket->ActualLength -= HTC_HDR_LENGTH;
 245
 246     } while (FALSE);
 247
 248     if (A_FAILED(status)) {
 249             /* dump the whole packet */
 250         DebugDumpBytes(pBuf,pPacket->ActualLength,"BAD HTC Recv PKT");
 251     } else {
 252 #ifdef HTC_CAPTURE_LAST_FRAME
 253         A_MEMCPY(&target->LastFrameHdr,pBuf,sizeof(HTC_FRAME_HDR));
 254 #endif
 255         if (AR_DEBUG_LVL_CHECK(ATH_DEBUG_RECV)) {
 256             if (pPacket->ActualLength > 0) {
 257                 AR_DEBUG_PRINTBUF(pPacket->pBuffer,pPacket->ActualLength,"HTC - Application Msg");
 258             }
 259         }
 260     }
 261
 262     AR_DEBUG_PRINTF(ATH_DEBUG_RECV, ("-HTCProcessRecvHeader \n"));
 263     return status;
 264 }
 265
 266 /* asynchronous completion handler for recv packet fetching, when the device layer
 267  * completes a read request, it will call this completion handler */
 268 void HTCRecvCompleteHandler(void *Context, HTC_PACKET *pPacket)
 269 {
 270     HTC_TARGET      *target = (HTC_TARGET *)Context;
 271     HTC_ENDPOINT    *pEndpoint;
 272     A_UINT32        nextLookAhead = 0;
 273     A_STATUS        status;
 274
 275     AR_DEBUG_PRINTF(ATH_DEBUG_RECV, ("+HTCRecvCompleteHandler (status:%d, ep:%d) \n",
 276                 pPacket->Status, pPacket->Endpoint));
 277
 278     AR_DEBUG_ASSERT(pPacket->Endpoint < ENDPOINT_MAX);
 279     pEndpoint = &target->EndPoint[pPacket->Endpoint];
 280     pPacket->Completion = NULL;
 281
 282         /* get completion status */
 283     status = pPacket->Status;
 284
 285     do {
 286         if (A_FAILED(status)) {
 287             AR_DEBUG_PRINTF(ATH_DEBUG_ERR, ("HTCRecvCompleteHandler: request failed (status:%d, ep:%d) \n",
 288                 pPacket->Status, pPacket->Endpoint));
 289             break;
 290         }
 291             /* process the header for any trailer data */
 292         status = HTCProcessRecvHeader(target,pPacket,&nextLookAhead);
 293
 294         if (A_FAILED(status)) {
 295             break;
 296         }
 297             /* was there a lookahead for the next packet? */
 298         if (nextLookAhead != 0) {
 299             A_STATUS nextStatus;
 300             AR_DEBUG_PRINTF(ATH_DEBUG_RECV,
 301                             ("HTCRecvCompleteHandler - next look ahead was non-zero : 0x%X \n",
 302                              nextLookAhead));
 303                 /* we have another packet, get the next packet fetch started (pipelined) before
 304                  * we call into the endpoint's callback, this will start another async request */
 305             nextStatus = HTCRecvMessagePendingHandler(target,nextLookAhead,NULL);
 306             if (A_EPROTO == nextStatus) {
 307                 AR_DEBUG_PRINTF(ATH_DEBUG_ERR,
 308                             ("Next look ahead from recv header was INVALID\n"));
 309                 DebugDumpBytes((A_UINT8 *)&nextLookAhead,
 310                                 4,
 311                                 "BAD lookahead from lookahead report");
 312             }
 313         } else {
 314              AR_DEBUG_PRINTF(ATH_DEBUG_RECV,
 315             ("HTCRecvCompleteHandler - rechecking for more messages...\n"));
 316             /* if we did not get anything on the look-ahead,
 317              * call device layer to asynchronously re-check for messages. If we can keep the async
 318              * processing going we get better performance.  If there is a pending message we will keep processing
 319              * messages asynchronously which should pipeline things nicely */
 320             DevCheckPendingRecvMsgsAsync(&target->Device);
 321         }
 322
 323         HTC_RX_STAT_PROFILE(target,pEndpoint,nextLookAhead);
 324         DO_RCV_COMPLETION(target,pPacket,pEndpoint);
 325
 326     } while (FALSE);
 327
 328     if (A_FAILED(status)) {
 329          AR_DEBUG_PRINTF(ATH_DEBUG_ERR,
 330                          ("HTCRecvCompleteHandler , message fetch failed (status = %d) \n",
 331                          status));
 332             /* recyle this packet */
 333          HTC_RECYCLE_RX_PKT(target, pPacket);
 334     }
 335
 336     AR_DEBUG_PRINTF(ATH_DEBUG_RECV, ("-HTCRecvCompleteHandler\n"));
 337 }
 338
 339 /* synchronously wait for a control message from the target,
 340  * This function is used at initialization time ONLY.  At init messages
 341  * on ENDPOINT 0 are expected. */
 342 A_STATUS HTCWaitforControlMessage(HTC_TARGET *target, HTC_PACKET **ppControlPacket)
 343 {
 344     A_STATUS        status;
 345     A_UINT32        lookAhead;
 346     HTC_PACKET      *pPacket = NULL;
 347     HTC_FRAME_HDR   *pHdr;
 348
 349     AR_DEBUG_PRINTF(ATH_DEBUG_RECV,("+HTCWaitforControlMessage \n"));
 350
 351     do  {
 352
 353         *ppControlPacket = NULL;
 354
 355             /* call the polling function to see if we have a message */
 356         status = DevPollMboxMsgRecv(&target->Device,
 357                                     &lookAhead,
 358                                     HTC_TARGET_RESPONSE_TIMEOUT);
 359
 360         if (A_FAILED(status)) {
 361             break;
 362         }
 363
 364         AR_DEBUG_PRINTF(ATH_DEBUG_RECV,
 365                 ("HTCWaitforControlMessage : lookAhead : 0x%X \n", lookAhead));
 366
 367             /* check the lookahead */
 368         pHdr = (HTC_FRAME_HDR *)&lookAhead;
 369
 370         if (pHdr->EndpointID != ENDPOINT_0) {
 371                 /* unexpected endpoint number, should be zero */
 372             AR_DEBUG_ASSERT(FALSE);
 373             status = A_EPROTO;
 374             break;
 375         }
 376
 377         if (A_FAILED(status)) {
 378                 /* bad message */
 379             AR_DEBUG_ASSERT(FALSE);
 380             status = A_EPROTO;
 381             break;
 382         }
 383
 384         pPacket = HTC_ALLOC_CONTROL_RX(target);
 385
 386         if (pPacket == NULL) {
 387             AR_DEBUG_ASSERT(FALSE);
 388             status = A_NO_MEMORY;
 389             break;
 390         }
 391
 392         pPacket->HTCReserved = lookAhead;
 393         pPacket->ActualLength = pHdr->PayloadLen + HTC_HDR_LENGTH;
 394
 395         if (pPacket->ActualLength > pPacket->BufferLength) {
 396             AR_DEBUG_ASSERT(FALSE);
 397             status = A_EPROTO;
 398             break;
 399         }
 400
 401             /* we want synchronous operation */
 402         pPacket->Completion = NULL;
 403
 404             /* get the message from the device, this will block */
 405         status = HTCIssueRecv(target, pPacket);
 406
 407         if (A_FAILED(status)) {
 408             break;
 409         }
 410
 411             /* process receive header */
 412         status = HTCProcessRecvHeader(target,pPacket,NULL);
 413
 414         pPacket->Status = status;
 415
 416         if (A_FAILED(status)) {
 417             AR_DEBUG_PRINTF(ATH_DEBUG_ERR,
 418                     ("HTCWaitforControlMessage, HTCProcessRecvHeader failed (status = %d) \n",
 419                      status));
 420             break;
 421         }
 422
 423             /* give the caller this control message packet, they are responsible to free */
 424         *ppControlPacket = pPacket;
 425
 426     } while (FALSE);
 427
 428     if (A_FAILED(status)) {
 429         if (pPacket != NULL) {
 430                 /* cleanup buffer on error */
 431             HTC_FREE_CONTROL_RX(target,pPacket);
 432         }
 433     }
 434
 435     AR_DEBUG_PRINTF(ATH_DEBUG_RECV,("-HTCWaitforControlMessage \n"));
 436
 437     return status;
 438 }
 439
 440 /* callback when device layer or lookahead report parsing detects a pending message */
 441 A_STATUS HTCRecvMessagePendingHandler(void *Context, A_UINT32 LookAhead, A_BOOL *pAsyncProc)
 442 {
 443     HTC_TARGET      *target = (HTC_TARGET *)Context;
 444     A_STATUS         status = A_OK;
 445     HTC_PACKET      *pPacket = NULL;
 446     HTC_FRAME_HDR   *pHdr;
 447     HTC_ENDPOINT    *pEndpoint;
 448     A_BOOL          asyncProc = FALSE;
 449
 450     AR_DEBUG_PRINTF(ATH_DEBUG_RECV,("+HTCRecvMessagePendingHandler LookAhead:0x%X \n",LookAhead));
 451
 452     if (IS_DEV_IRQ_PROCESSING_ASYNC_ALLOWED(&target->Device)) {
 453             /* We use async mode to get the packets if the device layer supports it.
 454              * The device layer interfaces with HIF in which HIF may have restrictions on
 455              * how interrupts are processed */
 456         asyncProc = TRUE;
 457     }
 458
 459     if (pAsyncProc != NULL) {
 460             /* indicate to caller how we decided to process this */
 461         *pAsyncProc = asyncProc;
 462     }
 463
 464     while (TRUE) {
 465
 466         pHdr = (HTC_FRAME_HDR *)&LookAhead;
 467
 468         if (pHdr->EndpointID >= ENDPOINT_MAX) {
 469             AR_DEBUG_PRINTF(ATH_DEBUG_ERR,("Invalid Endpoint in look-ahead: %d \n",pHdr->EndpointID));
 470                 /* invalid endpoint */
 471             status = A_EPROTO;
 472             break;
 473         }
 474
 475         if (pHdr->PayloadLen > HTC_MAX_PAYLOAD_LENGTH) {
 476             AR_DEBUG_PRINTF(ATH_DEBUG_ERR,("Payload length %d exceeds max HTC : %d !\n",
 477                     pHdr->PayloadLen, HTC_MAX_PAYLOAD_LENGTH));
 478             status = A_EPROTO;
 479             break;
 480         }
 481
 482         pEndpoint = &target->EndPoint[pHdr->EndpointID];
 483
 484         if (0 == pEndpoint->ServiceID) {
 485             AR_DEBUG_PRINTF(ATH_DEBUG_ERR,("Endpoint %d is not connected !\n",pHdr->EndpointID));
 486                 /* endpoint isn't even connected */
 487             status = A_EPROTO;
 488             break;
 489         }
 490
 491             /* lock RX to get a buffer */
 492         LOCK_HTC_RX(target);
 493
 494             /* get a packet from the endpoint recv queue */
 495         pPacket = HTC_PACKET_DEQUEUE(&pEndpoint->RxBuffers);
 496
 497         if (NULL == pPacket) {
 498                 /* check for refill handler */
 499             if (pEndpoint->EpCallBacks.EpRecvRefill != NULL) {
 500                 UNLOCK_HTC_RX(target);
 501                     /* call the re-fill handler */
 502                 pEndpoint->EpCallBacks.EpRecvRefill(pEndpoint->EpCallBacks.pContext,
 503                                                     pHdr->EndpointID);
 504                 LOCK_HTC_RX(target);
 505                     /* check if we have more buffers */
 506                 pPacket = HTC_PACKET_DEQUEUE(&pEndpoint->RxBuffers);
 507                     /* fall through */
 508             }
 509         }
 510
 511         if (NULL == pPacket) {
 512                 /* this is not an error, we simply need to mark that we are waiting for buffers.*/
 513             target->HTCStateFlags |= HTC_STATE_WAIT_BUFFERS;
 514             target->EpWaitingForBuffers = pHdr->EndpointID;
 515             status = A_NO_MEMORY;
 516         }
 517
 518         UNLOCK_HTC_RX(target);
 519
 520         if (A_FAILED(status)) {
 521                 /* no buffers */
 522             break;
 523         }
 524
 525         AR_DEBUG_ASSERT(pPacket->Endpoint == pHdr->EndpointID);
 526
 527             /* make sure this message can fit in the endpoint buffer */
 528         if ((pHdr->PayloadLen + HTC_HDR_LENGTH) > pPacket->BufferLength) {
 529             AR_DEBUG_PRINTF(ATH_DEBUG_ERR,
 530                     ("Payload Length Error : header reports payload of: %d, endpoint buffer size: %d \n",
 531                     pHdr->PayloadLen, pPacket->BufferLength));
 532             status = A_EPROTO;
 533             break;
 534         }
 535
 536         pPacket->HTCReserved = LookAhead; /* set expected look ahead */
 537             /* set the amount of data to fetch */
 538         pPacket->ActualLength = pHdr->PayloadLen + HTC_HDR_LENGTH;
 539
 540         if (asyncProc) {
 541                 /* we use async mode to get the packet if the device layer supports it
 542                  * set our callback and context */
 543             pPacket->Completion = HTCRecvCompleteHandler;
 544             pPacket->pContext = target;
 545         } else {
 546                 /* fully synchronous */
 547             pPacket->Completion = NULL;
 548         }
 549
 550             /* go fetch the packet */
 551         status = HTCIssueRecv(target, pPacket);
 552
 553         if (A_FAILED(status)) {
 554             break;
 555         }
 556
 557         if (asyncProc) {
 558                 /* we did this asynchronously so we can get out of the loop, the asynch processing
 559                  * creates a chain of requests to continue processing pending messages in the
 560                  * context of callbacks  */
 561             break;
 562         }
 563
 564             /* in the sync case, we process the packet, check lookaheads and then repeat */
 565
 566         LookAhead = 0;
 567         status = HTCProcessRecvHeader(target,pPacket,&LookAhead);
 568
 569         if (A_FAILED(status)) {
 570             break;
 571         }
 572
 573         HTC_RX_STAT_PROFILE(target,pEndpoint,LookAhead);
 574         DO_RCV_COMPLETION(target,pPacket,pEndpoint);
 575
 576         pPacket = NULL;
 577
 578         if (0 == LookAhead) {
 579             break;
 580         }
 581
 582     }
 583
 584     if (A_NO_MEMORY == status) {
 585         AR_DEBUG_PRINTF(ATH_DEBUG_ERR,
 586                 (" Endpoint :%d has no buffers, blocking receiver to prevent overrun.. \n",
 587                 pHdr->EndpointID));
 588             /* try to stop receive at the device layer */
 589         DevStopRecv(&target->Device, asyncProc ? DEV_STOP_RECV_ASYNC : DEV_STOP_RECV_SYNC);
 590         status = A_OK;
 591     } else if (A_FAILED(status)) {
 592         AR_DEBUG_PRINTF(ATH_DEBUG_ERR,
 593                         ("Failed to get pending message : LookAhead Value: 0x%X (status = %d) \n",
 594                         LookAhead, status));
 595         if (pPacket != NULL) {
 596                 /* clean up packet on error */
 597             HTC_RECYCLE_RX_PKT(target, pPacket);
 598         }
 599     }
 600
 601     AR_DEBUG_PRINTF(ATH_DEBUG_RECV,("-HTCRecvMessagePendingHandler \n"));
 602
 603     return status;
 604 }
 605
 606 /* Makes a buffer available to the HTC module */
 607 A_STATUS HTCAddReceivePkt(HTC_HANDLE HTCHandle, HTC_PACKET *pPacket)
 608 {
 609     HTC_TARGET *target = GET_HTC_TARGET_FROM_HANDLE(HTCHandle);
 610     HTC_ENDPOINT *pEndpoint;
 611     A_BOOL       unblockRecv = FALSE;
 612     A_STATUS     status = A_OK;
 613
 614     AR_DEBUG_PRINTF(ATH_DEBUG_SEND,
 615                     ("+- HTCAddReceivePkt: endPointId: %d, buffer: 0x%X, length: %d\n",
 616                     pPacket->Endpoint, (A_UINT32)pPacket->pBuffer, pPacket->BufferLength));
 617
 618     do {
 619
 620         if (HTC_STOPPING(target)) {
 621             status = A_ECANCELED;
 622             break;
 623         }
 624
 625         AR_DEBUG_ASSERT(pPacket->Endpoint < ENDPOINT_MAX);
 626
 627         pEndpoint = &target->EndPoint[pPacket->Endpoint];
 628
 629         LOCK_HTC_RX(target);
 630
 631             /* store receive packet */
 632         HTC_PACKET_ENQUEUE(&pEndpoint->RxBuffers, pPacket);
 633
 634             /* check if we are blocked waiting for a new buffer */
 635         if (target->HTCStateFlags & HTC_STATE_WAIT_BUFFERS) {
 636             if (target->EpWaitingForBuffers == pPacket->Endpoint) {
 637                 AR_DEBUG_PRINTF(ATH_DEBUG_RECV,(" receiver was blocked on ep:%d, unblocking.. \n",
 638                     target->EpWaitingForBuffers));
 639                 target->HTCStateFlags &= ~HTC_STATE_WAIT_BUFFERS;
 640                 target->EpWaitingForBuffers = ENDPOINT_MAX;
 641                 unblockRecv = TRUE;
 642             }
 643         }
 644
 645         UNLOCK_HTC_RX(target);
 646
 647         if (unblockRecv && !HTC_STOPPING(target)) {
 648                 /* TODO : implement a buffer threshold count? */
 649             DevEnableRecv(&target->Device,DEV_ENABLE_RECV_SYNC);
 650         }
 651
 652     } while (FALSE);
 653
 654     return status;
 655 }
 656
 657 static void HTCFlushEndpointRX(HTC_TARGET *target, HTC_ENDPOINT *pEndpoint)
 658 {
 659     HTC_PACKET  *pPacket;
 660
 661     LOCK_HTC_RX(target);
 662
 663     while (1) {
 664         pPacket = HTC_PACKET_DEQUEUE(&pEndpoint->RxBuffers);
 665         if (NULL == pPacket) {
 666             break;
 667         }
 668         UNLOCK_HTC_RX(target);
 669         pPacket->Status = A_ECANCELED;
 670         pPacket->ActualLength = 0;
 671         AR_DEBUG_PRINTF(ATH_DEBUG_RECV, ("  Flushing RX packet:0x%X, length:%d, ep:%d \n",
 672                 (A_UINT32)pPacket, pPacket->BufferLength, pPacket->Endpoint));
 673             /* give the packet back */
 674         pEndpoint->EpCallBacks.EpRecv(pEndpoint->EpCallBacks.pContext,
 675                                       pPacket);
 676         LOCK_HTC_RX(target);
 677     }
 678
 679     UNLOCK_HTC_RX(target);
 680
 681
 682 }
 683
 684 void HTCFlushRecvBuffers(HTC_TARGET *target)
 685 {
 686     HTC_ENDPOINT    *pEndpoint;
 687     int             i;
 688
 689         /* NOTE: no need to flush endpoint 0, these buffers were
 690          * allocated as part of the HTC struct */
 691     for (i = ENDPOINT_1; i < ENDPOINT_MAX; i++) {
 692         pEndpoint = &target->EndPoint[i];
 693         if (pEndpoint->ServiceID == 0) {
 694                 /* not in use.. */
 695             continue;
 696         }
 697         HTCFlushEndpointRX(target,pEndpoint);
 698     }
 699
 700
 701 }
 702
 703