err.no Git - linux-2.6/blob - drivers/net/wireless/rt2x00/rt2x00queue.c

   1 /*
   2         Copyright (C) 2004 - 2008 rt2x00 SourceForge Project
   3         <http://rt2x00.serialmonkey.com>
   4
   5         This program is free software; you can redistribute it and/or modify
   6         it under the terms of the GNU General Public License as published by
   7         the Free Software Foundation; either version 2 of the License, or
   8         (at your option) any later version.
   9
  10         This program is distributed in the hope that it will be useful,
  11         but WITHOUT ANY WARRANTY; without even the implied warranty of
  12         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13         GNU General Public License for more details.
  14
  15         You should have received a copy of the GNU General Public License
  16         along with this program; if not, write to the
  17         Free Software Foundation, Inc.,
  18         59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 /*
  22         Module: rt2x00lib
  23         Abstract: rt2x00 queue specific routines.
  24  */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/dma-mapping.h>
  29
  30 #include "rt2x00.h"
  31 #include "rt2x00lib.h"
  32
  33 struct sk_buff *rt2x00queue_alloc_rxskb(struct rt2x00_dev *rt2x00dev,
  34                                         struct queue_entry *entry)
  35 {
  36         unsigned int frame_size;
  37         unsigned int reserved_size;
  38         struct sk_buff *skb;
  39         struct skb_frame_desc *skbdesc;
  40
  41         /*
  42          * The frame size includes descriptor size, because the
  43          * hardware directly receive the frame into the skbuffer.
  44          */
  45         frame_size = entry->queue->data_size + entry->queue->desc_size;
  46
  47         /*
  48          * The payload should be aligned to a 4-byte boundary,
  49          * this means we need at least 3 bytes for moving the frame
  50          * into the correct offset.
  51          */
  52         reserved_size = 4;
  53
  54         /*
  55          * Allocate skbuffer.
  56          */
  57         skb = dev_alloc_skb(frame_size + reserved_size);
  58         if (!skb)
  59                 return NULL;
  60
  61         skb_reserve(skb, reserved_size);
  62         skb_put(skb, frame_size);
  63
  64         /*
  65          * Populate skbdesc.
  66          */
  67         skbdesc = get_skb_frame_desc(skb);
  68         memset(skbdesc, 0, sizeof(*skbdesc));
  69         skbdesc->entry = entry;
  70
  71         if (test_bit(DRIVER_REQUIRE_DMA, &rt2x00dev->flags)) {
  72                 skbdesc->skb_dma = dma_map_single(rt2x00dev->dev,
  73                                                   skb->data,
  74                                                   skb->len,
  75                                                   DMA_FROM_DEVICE);
  76                 skbdesc->flags |= SKBDESC_DMA_MAPPED_RX;
  77         }
  78
  79         return skb;
  80 }
  81
  82 void rt2x00queue_map_txskb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
  83 {
  84         struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
  85
  86         skbdesc->skb_dma = dma_map_single(rt2x00dev->dev, skb->data, skb->len,
  87                                           DMA_TO_DEVICE);
  88         skbdesc->flags |= SKBDESC_DMA_MAPPED_TX;
  89 }
  90 EXPORT_SYMBOL_GPL(rt2x00queue_map_txskb);
  91
  92 void rt2x00queue_unmap_skb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
  93 {
  94         struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
  95
  96         if (skbdesc->flags & SKBDESC_DMA_MAPPED_RX) {
  97                 dma_unmap_single(rt2x00dev->dev, skbdesc->skb_dma, skb->len,
  98                                  DMA_FROM_DEVICE);
  99                 skbdesc->flags &= ~SKBDESC_DMA_MAPPED_RX;
 100         }
 101
 102         if (skbdesc->flags & SKBDESC_DMA_MAPPED_TX) {
 103                 dma_unmap_single(rt2x00dev->dev, skbdesc->skb_dma, skb->len,
 104                                  DMA_TO_DEVICE);
 105                 skbdesc->flags &= ~SKBDESC_DMA_MAPPED_TX;
 106         }
 107 }
 108
 109 void rt2x00queue_free_skb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
 110 {
 111         rt2x00queue_unmap_skb(rt2x00dev, skb);
 112         dev_kfree_skb_any(skb);
 113 }
 114
 115 void rt2x00queue_create_tx_descriptor(struct queue_entry *entry,
 116                                       struct txentry_desc *txdesc)
 117 {
 118         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 119         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
 120         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)entry->skb->data;
 121         struct ieee80211_rate *rate =
 122             ieee80211_get_tx_rate(rt2x00dev->hw, tx_info);
 123         const struct rt2x00_rate *hwrate;
 124         unsigned int data_length;
 125         unsigned int duration;
 126         unsigned int residual;
 127
 128         memset(txdesc, 0, sizeof(*txdesc));
 129
 130         /*
 131          * Initialize information from queue
 132          */
 133         txdesc->queue = entry->queue->qid;
 134         txdesc->cw_min = entry->queue->cw_min;
 135         txdesc->cw_max = entry->queue->cw_max;
 136         txdesc->aifs = entry->queue->aifs;
 137
 138         /* Data length should be extended with 4 bytes for CRC */
 139         data_length = entry->skb->len + 4;
 140
 141         /*
 142          * Check whether this frame is to be acked.
 143          */
 144         if (!(tx_info->flags & IEEE80211_TX_CTL_NO_ACK))
 145                 __set_bit(ENTRY_TXD_ACK, &txdesc->flags);
 146
 147         /*
 148          * Check if this is a RTS/CTS frame
 149          */
 150         if (ieee80211_is_rts(hdr->frame_control) ||
 151             ieee80211_is_cts(hdr->frame_control)) {
 152                 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
 153                 if (ieee80211_is_rts(hdr->frame_control))
 154                         __set_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags);
 155                 else
 156                         __set_bit(ENTRY_TXD_CTS_FRAME, &txdesc->flags);
 157                 if (tx_info->control.rts_cts_rate_idx >= 0)
 158                         rate =
 159                             ieee80211_get_rts_cts_rate(rt2x00dev->hw, tx_info);
 160         }
 161
 162         /*
 163          * Determine retry information.
 164          */
 165         txdesc->retry_limit = tx_info->control.retry_limit;
 166         if (tx_info->flags & IEEE80211_TX_CTL_LONG_RETRY_LIMIT)
 167                 __set_bit(ENTRY_TXD_RETRY_MODE, &txdesc->flags);
 168
 169         /*
 170          * Check if more fragments are pending
 171          */
 172         if (ieee80211_has_morefrags(hdr->frame_control)) {
 173                 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
 174                 __set_bit(ENTRY_TXD_MORE_FRAG, &txdesc->flags);
 175         }
 176
 177         /*
 178          * Beacons and probe responses require the tsf timestamp
 179          * to be inserted into the frame.
 180          */
 181         if (ieee80211_is_beacon(hdr->frame_control) ||
 182             ieee80211_is_probe_resp(hdr->frame_control))
 183                 __set_bit(ENTRY_TXD_REQ_TIMESTAMP, &txdesc->flags);
 184
 185         /*
 186          * Determine with what IFS priority this frame should be send.
 187          * Set ifs to IFS_SIFS when the this is not the first fragment,
 188          * or this fragment came after RTS/CTS.
 189          */
 190         if (test_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags)) {
 191                 txdesc->ifs = IFS_SIFS;
 192         } else if (tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT) {
 193                 __set_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags);
 194                 txdesc->ifs = IFS_BACKOFF;
 195         } else {
 196                 txdesc->ifs = IFS_SIFS;
 197         }
 198
 199         /*
 200          * PLCP setup
 201          * Length calculation depends on OFDM/CCK rate.
 202          */
 203         hwrate = rt2x00_get_rate(rate->hw_value);
 204         txdesc->signal = hwrate->plcp;
 205         txdesc->service = 0x04;
 206
 207         if (hwrate->flags & DEV_RATE_OFDM) {
 208                 __set_bit(ENTRY_TXD_OFDM_RATE, &txdesc->flags);
 209
 210                 txdesc->length_high = (data_length >> 6) & 0x3f;
 211                 txdesc->length_low = data_length & 0x3f;
 212         } else {
 213                 /*
 214                  * Convert length to microseconds.
 215                  */
 216                 residual = get_duration_res(data_length, hwrate->bitrate);
 217                 duration = get_duration(data_length, hwrate->bitrate);
 218
 219                 if (residual != 0) {
 220                         duration++;
 221
 222                         /*
 223                          * Check if we need to set the Length Extension
 224                          */
 225                         if (hwrate->bitrate == 110 && residual <= 30)
 226                                 txdesc->service |= 0x80;
 227                 }
 228
 229                 txdesc->length_high = (duration >> 8) & 0xff;
 230                 txdesc->length_low = duration & 0xff;
 231
 232                 /*
 233                  * When preamble is enabled we should set the
 234                  * preamble bit for the signal.
 235                  */
 236                 if (rt2x00_get_rate_preamble(rate->hw_value))
 237                         txdesc->signal |= 0x08;
 238         }
 239 }
 240 EXPORT_SYMBOL_GPL(rt2x00queue_create_tx_descriptor);
 241
 242 void rt2x00queue_write_tx_descriptor(struct queue_entry *entry,
 243                                      struct txentry_desc *txdesc)
 244 {
 245         struct data_queue *queue = entry->queue;
 246         struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
 247
 248         rt2x00dev->ops->lib->write_tx_desc(rt2x00dev, entry->skb, txdesc);
 249
 250         /*
 251          * All processing on the frame has been completed, this means
 252          * it is now ready to be dumped to userspace through debugfs.
 253          */
 254         rt2x00debug_dump_frame(rt2x00dev, DUMP_FRAME_TX, entry->skb);
 255
 256         /*
 257          * Check if we need to kick the queue, there are however a few rules
 258          *      1) Don't kick beacon queue
 259          *      2) Don't kick unless this is the last in frame in a burst.
 260          *         When the burst flag is set, this frame is always followed
 261          *         by another frame which in some way are related to eachother.
 262          *         This is true for fragments, RTS or CTS-to-self frames.
 263          *      3) Rule 2 can be broken when the available entries
 264          *         in the queue are less then a certain threshold.
 265          */
 266         if (entry->queue->qid == QID_BEACON)
 267                 return;
 268
 269         if (rt2x00queue_threshold(queue) ||
 270             !test_bit(ENTRY_TXD_BURST, &txdesc->flags))
 271                 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, queue->qid);
 272 }
 273 EXPORT_SYMBOL_GPL(rt2x00queue_write_tx_descriptor);
 274
 275 int rt2x00queue_write_tx_frame(struct data_queue *queue, struct sk_buff *skb)
 276 {
 277         struct queue_entry *entry = rt2x00queue_get_entry(queue, Q_INDEX);
 278         struct txentry_desc txdesc;
 279         struct skb_frame_desc *skbdesc;
 280
 281         if (unlikely(rt2x00queue_full(queue)))
 282                 return -EINVAL;
 283
 284         if (__test_and_set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags)) {
 285                 ERROR(queue->rt2x00dev,
 286                       "Arrived at non-free entry in the non-full queue %d.\n"
 287                       "Please file bug report to %s.\n",
 288                       queue->qid, DRV_PROJECT);
 289                 return -EINVAL;
 290         }
 291
 292         /*
 293          * Copy all TX descriptor information into txdesc,
 294          * after that we are free to use the skb->cb array
 295          * for our information.
 296          */
 297         entry->skb = skb;
 298         rt2x00queue_create_tx_descriptor(entry, &txdesc);
 299
 300         /*
 301          * skb->cb array is now ours and we are free to use it.
 302          */
 303         skbdesc = get_skb_frame_desc(entry->skb);
 304         memset(skbdesc, 0, sizeof(*skbdesc));
 305         skbdesc->entry = entry;
 306
 307         if (unlikely(queue->rt2x00dev->ops->lib->write_tx_data(entry))) {
 308                 __clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
 309                 return -EIO;
 310         }
 311
 312         if (test_bit(DRIVER_REQUIRE_DMA, &queue->rt2x00dev->flags))
 313                 rt2x00queue_map_txskb(queue->rt2x00dev, skb);
 314
 315         __set_bit(ENTRY_DATA_PENDING, &entry->flags);
 316
 317         rt2x00queue_index_inc(queue, Q_INDEX);
 318         rt2x00queue_write_tx_descriptor(entry, &txdesc);
 319
 320         return 0;
 321 }
 322
 323 struct data_queue *rt2x00queue_get_queue(struct rt2x00_dev *rt2x00dev,
 324                                          const enum data_queue_qid queue)
 325 {
 326         int atim = test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
 327
 328         if (queue < rt2x00dev->ops->tx_queues && rt2x00dev->tx)
 329                 return &rt2x00dev->tx[queue];
 330
 331         if (!rt2x00dev->bcn)
 332                 return NULL;
 333
 334         if (queue == QID_BEACON)
 335                 return &rt2x00dev->bcn[0];
 336         else if (queue == QID_ATIM && atim)
 337                 return &rt2x00dev->bcn[1];
 338
 339         return NULL;
 340 }
 341 EXPORT_SYMBOL_GPL(rt2x00queue_get_queue);
 342
 343 struct queue_entry *rt2x00queue_get_entry(struct data_queue *queue,
 344                                           enum queue_index index)
 345 {
 346         struct queue_entry *entry;
 347         unsigned long irqflags;
 348
 349         if (unlikely(index >= Q_INDEX_MAX)) {
 350                 ERROR(queue->rt2x00dev,
 351                       "Entry requested from invalid index type (%d)\n", index);
 352                 return NULL;
 353         }
 354
 355         spin_lock_irqsave(&queue->lock, irqflags);
 356
 357         entry = &queue->entries[queue->index[index]];
 358
 359         spin_unlock_irqrestore(&queue->lock, irqflags);
 360
 361         return entry;
 362 }
 363 EXPORT_SYMBOL_GPL(rt2x00queue_get_entry);
 364
 365 void rt2x00queue_index_inc(struct data_queue *queue, enum queue_index index)
 366 {
 367         unsigned long irqflags;
 368
 369         if (unlikely(index >= Q_INDEX_MAX)) {
 370                 ERROR(queue->rt2x00dev,
 371                       "Index change on invalid index type (%d)\n", index);
 372                 return;
 373         }
 374
 375         spin_lock_irqsave(&queue->lock, irqflags);
 376
 377         queue->index[index]++;
 378         if (queue->index[index] >= queue->limit)
 379                 queue->index[index] = 0;
 380
 381         if (index == Q_INDEX) {
 382                 queue->length++;
 383         } else if (index == Q_INDEX_DONE) {
 384                 queue->length--;
 385                 queue->count ++;
 386         }
 387
 388         spin_unlock_irqrestore(&queue->lock, irqflags);
 389 }
 390
 391 static void rt2x00queue_reset(struct data_queue *queue)
 392 {
 393         unsigned long irqflags;
 394
 395         spin_lock_irqsave(&queue->lock, irqflags);
 396
 397         queue->count = 0;
 398         queue->length = 0;
 399         memset(queue->index, 0, sizeof(queue->index));
 400
 401         spin_unlock_irqrestore(&queue->lock, irqflags);
 402 }
 403
 404 void rt2x00queue_init_rx(struct rt2x00_dev *rt2x00dev)
 405 {
 406         struct data_queue *queue = rt2x00dev->rx;
 407         unsigned int i;
 408
 409         rt2x00queue_reset(queue);
 410
 411         if (!rt2x00dev->ops->lib->init_rxentry)
 412                 return;
 413
 414         for (i = 0; i < queue->limit; i++)
 415                 rt2x00dev->ops->lib->init_rxentry(rt2x00dev,
 416                                                   &queue->entries[i]);
 417 }
 418
 419 void rt2x00queue_init_tx(struct rt2x00_dev *rt2x00dev)
 420 {
 421         struct data_queue *queue;
 422         unsigned int i;
 423
 424         txall_queue_for_each(rt2x00dev, queue) {
 425                 rt2x00queue_reset(queue);
 426
 427                 if (!rt2x00dev->ops->lib->init_txentry)
 428                         continue;
 429
 430                 for (i = 0; i < queue->limit; i++)
 431                         rt2x00dev->ops->lib->init_txentry(rt2x00dev,
 432                                                           &queue->entries[i]);
 433         }
 434 }
 435
 436 static int rt2x00queue_alloc_entries(struct data_queue *queue,
 437                                      const struct data_queue_desc *qdesc)
 438 {
 439         struct queue_entry *entries;
 440         unsigned int entry_size;
 441         unsigned int i;
 442
 443         rt2x00queue_reset(queue);
 444
 445         queue->limit = qdesc->entry_num;
 446         queue->threshold = DIV_ROUND_UP(qdesc->entry_num, 10);
 447         queue->data_size = qdesc->data_size;
 448         queue->desc_size = qdesc->desc_size;
 449
 450         /*
 451          * Allocate all queue entries.
 452          */
 453         entry_size = sizeof(*entries) + qdesc->priv_size;
 454         entries = kzalloc(queue->limit * entry_size, GFP_KERNEL);
 455         if (!entries)
 456                 return -ENOMEM;
 457
 458 #define QUEUE_ENTRY_PRIV_OFFSET(__base, __index, __limit, __esize, __psize) \
 459         ( ((char *)(__base)) + ((__limit) * (__esize)) + \
 460             ((__index) * (__psize)) )
 461
 462         for (i = 0; i < queue->limit; i++) {
 463                 entries[i].flags = 0;
 464                 entries[i].queue = queue;
 465                 entries[i].skb = NULL;
 466                 entries[i].entry_idx = i;
 467                 entries[i].priv_data =
 468                     QUEUE_ENTRY_PRIV_OFFSET(entries, i, queue->limit,
 469                                             sizeof(*entries), qdesc->priv_size);
 470         }
 471
 472 #undef QUEUE_ENTRY_PRIV_OFFSET
 473
 474         queue->entries = entries;
 475
 476         return 0;
 477 }
 478
 479 static void rt2x00queue_free_skbs(struct rt2x00_dev *rt2x00dev,
 480                                   struct data_queue *queue)
 481 {
 482         unsigned int i;
 483
 484         if (!queue->entries)
 485                 return;
 486
 487         for (i = 0; i < queue->limit; i++) {
 488                 if (queue->entries[i].skb)
 489                         rt2x00queue_free_skb(rt2x00dev, queue->entries[i].skb);
 490         }
 491 }
 492
 493 static int rt2x00queue_alloc_rxskbs(struct rt2x00_dev *rt2x00dev,
 494                                     struct data_queue *queue)
 495 {
 496         unsigned int i;
 497         struct sk_buff *skb;
 498
 499         for (i = 0; i < queue->limit; i++) {
 500                 skb = rt2x00queue_alloc_rxskb(rt2x00dev, &queue->entries[i]);
 501                 if (!skb)
 502                         return -ENOMEM;
 503                 queue->entries[i].skb = skb;
 504         }
 505
 506         return 0;
 507 }
 508
 509 int rt2x00queue_initialize(struct rt2x00_dev *rt2x00dev)
 510 {
 511         struct data_queue *queue;
 512         int status;
 513
 514         status = rt2x00queue_alloc_entries(rt2x00dev->rx, rt2x00dev->ops->rx);
 515         if (status)
 516                 goto exit;
 517
 518         tx_queue_for_each(rt2x00dev, queue) {
 519                 status = rt2x00queue_alloc_entries(queue, rt2x00dev->ops->tx);
 520                 if (status)
 521                         goto exit;
 522         }
 523
 524         status = rt2x00queue_alloc_entries(rt2x00dev->bcn, rt2x00dev->ops->bcn);
 525         if (status)
 526                 goto exit;
 527
 528         if (test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags)) {
 529                 status = rt2x00queue_alloc_entries(&rt2x00dev->bcn[1],
 530                                                    rt2x00dev->ops->atim);
 531                 if (status)
 532                         goto exit;
 533         }
 534
 535         status = rt2x00queue_alloc_rxskbs(rt2x00dev, rt2x00dev->rx);
 536         if (status)
 537                 goto exit;
 538
 539         return 0;
 540
 541 exit:
 542         ERROR(rt2x00dev, "Queue entries allocation failed.\n");
 543
 544         rt2x00queue_uninitialize(rt2x00dev);
 545
 546         return status;
 547 }
 548
 549 void rt2x00queue_uninitialize(struct rt2x00_dev *rt2x00dev)
 550 {
 551         struct data_queue *queue;
 552
 553         rt2x00queue_free_skbs(rt2x00dev, rt2x00dev->rx);
 554
 555         queue_for_each(rt2x00dev, queue) {
 556                 kfree(queue->entries);
 557                 queue->entries = NULL;
 558         }
 559 }
 560
 561 static void rt2x00queue_init(struct rt2x00_dev *rt2x00dev,
 562                              struct data_queue *queue, enum data_queue_qid qid)
 563 {
 564         spin_lock_init(&queue->lock);
 565
 566         queue->rt2x00dev = rt2x00dev;
 567         queue->qid = qid;
 568         queue->aifs = 2;
 569         queue->cw_min = 5;
 570         queue->cw_max = 10;
 571 }
 572
 573 int rt2x00queue_allocate(struct rt2x00_dev *rt2x00dev)
 574 {
 575         struct data_queue *queue;
 576         enum data_queue_qid qid;
 577         unsigned int req_atim =
 578             !!test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
 579
 580         /*
 581          * We need the following queues:
 582          * RX: 1
 583          * TX: ops->tx_queues
 584          * Beacon: 1
 585          * Atim: 1 (if required)
 586          */
 587         rt2x00dev->data_queues = 2 + rt2x00dev->ops->tx_queues + req_atim;
 588
 589         queue = kzalloc(rt2x00dev->data_queues * sizeof(*queue), GFP_KERNEL);
 590         if (!queue) {
 591                 ERROR(rt2x00dev, "Queue allocation failed.\n");
 592                 return -ENOMEM;
 593         }
 594
 595         /*
 596          * Initialize pointers
 597          */
 598         rt2x00dev->rx = queue;
 599         rt2x00dev->tx = &queue[1];
 600         rt2x00dev->bcn = &queue[1 + rt2x00dev->ops->tx_queues];
 601
 602         /*
 603          * Initialize queue parameters.
 604          * RX: qid = QID_RX
 605          * TX: qid = QID_AC_BE + index
 606          * TX: cw_min: 2^5 = 32.
 607          * TX: cw_max: 2^10 = 1024.
 608          * BCN: qid = QID_BEACON
 609          * ATIM: qid = QID_ATIM
 610          */
 611         rt2x00queue_init(rt2x00dev, rt2x00dev->rx, QID_RX);
 612
 613         qid = QID_AC_BE;
 614         tx_queue_for_each(rt2x00dev, queue)
 615                 rt2x00queue_init(rt2x00dev, queue, qid++);
 616
 617         rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[0], QID_BEACON);
 618         if (req_atim)
 619                 rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[1], QID_ATIM);
 620
 621         return 0;
 622 }
 623
 624 void rt2x00queue_free(struct rt2x00_dev *rt2x00dev)
 625 {
 626         kfree(rt2x00dev->rx);
 627         rt2x00dev->rx = NULL;
 628         rt2x00dev->tx = NULL;
 629         rt2x00dev->bcn = NULL;
 630 }