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         if (!skb)
 112                 return;
 113
 114         rt2x00queue_unmap_skb(rt2x00dev, skb);
 115         dev_kfree_skb_any(skb);
 116 }
 117
 118 static void rt2x00queue_create_tx_descriptor(struct queue_entry *entry,
 119                                              struct txentry_desc *txdesc)
 120 {
 121         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 122         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
 123         struct rt2x00_intf *intf = vif_to_intf(tx_info->control.vif);
 124         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)entry->skb->data;
 125         struct ieee80211_rate *rate =
 126             ieee80211_get_tx_rate(rt2x00dev->hw, tx_info);
 127         const struct rt2x00_rate *hwrate;
 128         unsigned int data_length;
 129         unsigned int duration;
 130         unsigned int residual;
 131
 132         memset(txdesc, 0, sizeof(*txdesc));
 133
 134         /*
 135          * Initialize information from queue
 136          */
 137         txdesc->queue = entry->queue->qid;
 138         txdesc->cw_min = entry->queue->cw_min;
 139         txdesc->cw_max = entry->queue->cw_max;
 140         txdesc->aifs = entry->queue->aifs;
 141
 142         /* Data length should be extended with 4 bytes for CRC */
 143         data_length = entry->skb->len + 4;
 144
 145         /*
 146          * Check whether this frame is to be acked.
 147          */
 148         if (!(tx_info->flags & IEEE80211_TX_CTL_NO_ACK))
 149                 __set_bit(ENTRY_TXD_ACK, &txdesc->flags);
 150
 151         /*
 152          * Check if this is a RTS/CTS frame
 153          */
 154         if (ieee80211_is_rts(hdr->frame_control) ||
 155             ieee80211_is_cts(hdr->frame_control)) {
 156                 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
 157                 if (ieee80211_is_rts(hdr->frame_control))
 158                         __set_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags);
 159                 else
 160                         __set_bit(ENTRY_TXD_CTS_FRAME, &txdesc->flags);
 161                 if (tx_info->control.rts_cts_rate_idx >= 0)
 162                         rate =
 163                             ieee80211_get_rts_cts_rate(rt2x00dev->hw, tx_info);
 164         }
 165
 166         /*
 167          * Determine retry information.
 168          */
 169         txdesc->retry_limit = tx_info->control.retry_limit;
 170         if (tx_info->flags & IEEE80211_TX_CTL_LONG_RETRY_LIMIT)
 171                 __set_bit(ENTRY_TXD_RETRY_MODE, &txdesc->flags);
 172
 173         /*
 174          * Check if more fragments are pending
 175          */
 176         if (ieee80211_has_morefrags(hdr->frame_control)) {
 177                 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
 178                 __set_bit(ENTRY_TXD_MORE_FRAG, &txdesc->flags);
 179         }
 180
 181         /*
 182          * Beacons and probe responses require the tsf timestamp
 183          * to be inserted into the frame.
 184          */
 185         if (ieee80211_is_beacon(hdr->frame_control) ||
 186             ieee80211_is_probe_resp(hdr->frame_control))
 187                 __set_bit(ENTRY_TXD_REQ_TIMESTAMP, &txdesc->flags);
 188
 189         /*
 190          * Determine with what IFS priority this frame should be send.
 191          * Set ifs to IFS_SIFS when the this is not the first fragment,
 192          * or this fragment came after RTS/CTS.
 193          */
 194         if (test_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags)) {
 195                 txdesc->ifs = IFS_SIFS;
 196         } else if (tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT) {
 197                 __set_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags);
 198                 txdesc->ifs = IFS_BACKOFF;
 199         } else {
 200                 txdesc->ifs = IFS_SIFS;
 201         }
 202
 203         /*
 204          * Hardware should insert sequence counter.
 205          * FIXME: We insert a software sequence counter first for
 206          * hardware that doesn't support hardware sequence counting.
 207          *
 208          * This is wrong because beacons are not getting sequence
 209          * numbers assigned properly.
 210          *
 211          * A secondary problem exists for drivers that cannot toggle
 212          * sequence counting per-frame, since those will override the
 213          * sequence counter given by mac80211.
 214          */
 215         if (tx_info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
 216                 spin_lock(&intf->lock);
 217
 218                 if (test_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags))
 219                         intf->seqno += 0x10;
 220                 hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
 221                 hdr->seq_ctrl |= cpu_to_le16(intf->seqno);
 222
 223                 spin_unlock(&intf->lock);
 224
 225                 __set_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
 226         }
 227
 228         /*
 229          * PLCP setup
 230          * Length calculation depends on OFDM/CCK rate.
 231          */
 232         hwrate = rt2x00_get_rate(rate->hw_value);
 233         txdesc->signal = hwrate->plcp;
 234         txdesc->service = 0x04;
 235
 236         if (hwrate->flags & DEV_RATE_OFDM) {
 237                 __set_bit(ENTRY_TXD_OFDM_RATE, &txdesc->flags);
 238
 239                 txdesc->length_high = (data_length >> 6) & 0x3f;
 240                 txdesc->length_low = data_length & 0x3f;
 241         } else {
 242                 /*
 243                  * Convert length to microseconds.
 244                  */
 245                 residual = get_duration_res(data_length, hwrate->bitrate);
 246                 duration = get_duration(data_length, hwrate->bitrate);
 247
 248                 if (residual != 0) {
 249                         duration++;
 250
 251                         /*
 252                          * Check if we need to set the Length Extension
 253                          */
 254                         if (hwrate->bitrate == 110 && residual <= 30)
 255                                 txdesc->service |= 0x80;
 256                 }
 257
 258                 txdesc->length_high = (duration >> 8) & 0xff;
 259                 txdesc->length_low = duration & 0xff;
 260
 261                 /*
 262                  * When preamble is enabled we should set the
 263                  * preamble bit for the signal.
 264                  */
 265                 if (rt2x00_get_rate_preamble(rate->hw_value))
 266                         txdesc->signal |= 0x08;
 267         }
 268 }
 269
 270 static void rt2x00queue_write_tx_descriptor(struct queue_entry *entry,
 271                                             struct txentry_desc *txdesc)
 272 {
 273         struct data_queue *queue = entry->queue;
 274         struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
 275
 276         rt2x00dev->ops->lib->write_tx_desc(rt2x00dev, entry->skb, txdesc);
 277
 278         /*
 279          * All processing on the frame has been completed, this means
 280          * it is now ready to be dumped to userspace through debugfs.
 281          */
 282         rt2x00debug_dump_frame(rt2x00dev, DUMP_FRAME_TX, entry->skb);
 283
 284         /*
 285          * Check if we need to kick the queue, there are however a few rules
 286          *      1) Don't kick beacon queue
 287          *      2) Don't kick unless this is the last in frame in a burst.
 288          *         When the burst flag is set, this frame is always followed
 289          *         by another frame which in some way are related to eachother.
 290          *         This is true for fragments, RTS or CTS-to-self frames.
 291          *      3) Rule 2 can be broken when the available entries
 292          *         in the queue are less then a certain threshold.
 293          */
 294         if (entry->queue->qid == QID_BEACON)
 295                 return;
 296
 297         if (rt2x00queue_threshold(queue) ||
 298             !test_bit(ENTRY_TXD_BURST, &txdesc->flags))
 299                 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, queue->qid);
 300 }
 301
 302 int rt2x00queue_write_tx_frame(struct data_queue *queue, struct sk_buff *skb)
 303 {
 304         struct queue_entry *entry = rt2x00queue_get_entry(queue, Q_INDEX);
 305         struct txentry_desc txdesc;
 306         struct skb_frame_desc *skbdesc;
 307
 308         if (unlikely(rt2x00queue_full(queue)))
 309                 return -EINVAL;
 310
 311         if (__test_and_set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags)) {
 312                 ERROR(queue->rt2x00dev,
 313                       "Arrived at non-free entry in the non-full queue %d.\n"
 314                       "Please file bug report to %s.\n",
 315                       queue->qid, DRV_PROJECT);
 316                 return -EINVAL;
 317         }
 318
 319         /*
 320          * Copy all TX descriptor information into txdesc,
 321          * after that we are free to use the skb->cb array
 322          * for our information.
 323          */
 324         entry->skb = skb;
 325         rt2x00queue_create_tx_descriptor(entry, &txdesc);
 326
 327         /*
 328          * skb->cb array is now ours and we are free to use it.
 329          */
 330         skbdesc = get_skb_frame_desc(entry->skb);
 331         memset(skbdesc, 0, sizeof(*skbdesc));
 332         skbdesc->entry = entry;
 333
 334         if (unlikely(queue->rt2x00dev->ops->lib->write_tx_data(entry))) {
 335                 __clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
 336                 return -EIO;
 337         }
 338
 339         if (test_bit(DRIVER_REQUIRE_DMA, &queue->rt2x00dev->flags))
 340                 rt2x00queue_map_txskb(queue->rt2x00dev, skb);
 341
 342         __set_bit(ENTRY_DATA_PENDING, &entry->flags);
 343
 344         rt2x00queue_index_inc(queue, Q_INDEX);
 345         rt2x00queue_write_tx_descriptor(entry, &txdesc);
 346
 347         return 0;
 348 }
 349
 350 int rt2x00queue_update_beacon(struct rt2x00_dev *rt2x00dev,
 351                               struct ieee80211_vif *vif)
 352 {
 353         struct rt2x00_intf *intf = vif_to_intf(vif);
 354         struct skb_frame_desc *skbdesc;
 355         struct txentry_desc txdesc;
 356         __le32 desc[16];
 357
 358         if (unlikely(!intf->beacon))
 359                 return -ENOBUFS;
 360
 361         intf->beacon->skb = ieee80211_beacon_get(rt2x00dev->hw, vif);
 362         if (!intf->beacon->skb)
 363                 return -ENOMEM;
 364
 365         /*
 366          * Copy all TX descriptor information into txdesc,
 367          * after that we are free to use the skb->cb array
 368          * for our information.
 369          */
 370         rt2x00queue_create_tx_descriptor(intf->beacon, &txdesc);
 371
 372         /*
 373          * For the descriptor we use a local array from where the
 374          * driver can move it to the correct location required for
 375          * the hardware.
 376          */
 377         memset(desc, 0, sizeof(desc));
 378
 379         /*
 380          * Fill in skb descriptor
 381          */
 382         skbdesc = get_skb_frame_desc(intf->beacon->skb);
 383         memset(skbdesc, 0, sizeof(*skbdesc));
 384         skbdesc->desc = desc;
 385         skbdesc->desc_len = intf->beacon->queue->desc_size;
 386         skbdesc->entry = intf->beacon;
 387
 388         /*
 389          * Write TX descriptor into reserved room in front of the beacon.
 390          */
 391         rt2x00queue_write_tx_descriptor(intf->beacon, &txdesc);
 392
 393         /*
 394          * Send beacon to hardware.
 395          * Also enable beacon generation, which might have been disabled
 396          * by the driver during the config_beacon() callback function.
 397          */
 398         rt2x00dev->ops->lib->write_beacon(intf->beacon);
 399         rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, QID_BEACON);
 400
 401         return 0;
 402 }
 403
 404 struct data_queue *rt2x00queue_get_queue(struct rt2x00_dev *rt2x00dev,
 405                                          const enum data_queue_qid queue)
 406 {
 407         int atim = test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
 408
 409         if (queue < rt2x00dev->ops->tx_queues && rt2x00dev->tx)
 410                 return &rt2x00dev->tx[queue];
 411
 412         if (!rt2x00dev->bcn)
 413                 return NULL;
 414
 415         if (queue == QID_BEACON)
 416                 return &rt2x00dev->bcn[0];
 417         else if (queue == QID_ATIM && atim)
 418                 return &rt2x00dev->bcn[1];
 419
 420         return NULL;
 421 }
 422 EXPORT_SYMBOL_GPL(rt2x00queue_get_queue);
 423
 424 struct queue_entry *rt2x00queue_get_entry(struct data_queue *queue,
 425                                           enum queue_index index)
 426 {
 427         struct queue_entry *entry;
 428         unsigned long irqflags;
 429
 430         if (unlikely(index >= Q_INDEX_MAX)) {
 431                 ERROR(queue->rt2x00dev,
 432                       "Entry requested from invalid index type (%d)\n", index);
 433                 return NULL;
 434         }
 435
 436         spin_lock_irqsave(&queue->lock, irqflags);
 437
 438         entry = &queue->entries[queue->index[index]];
 439
 440         spin_unlock_irqrestore(&queue->lock, irqflags);
 441
 442         return entry;
 443 }
 444 EXPORT_SYMBOL_GPL(rt2x00queue_get_entry);
 445
 446 void rt2x00queue_index_inc(struct data_queue *queue, enum queue_index index)
 447 {
 448         unsigned long irqflags;
 449
 450         if (unlikely(index >= Q_INDEX_MAX)) {
 451                 ERROR(queue->rt2x00dev,
 452                       "Index change on invalid index type (%d)\n", index);
 453                 return;
 454         }
 455
 456         spin_lock_irqsave(&queue->lock, irqflags);
 457
 458         queue->index[index]++;
 459         if (queue->index[index] >= queue->limit)
 460                 queue->index[index] = 0;
 461
 462         if (index == Q_INDEX) {
 463                 queue->length++;
 464         } else if (index == Q_INDEX_DONE) {
 465                 queue->length--;
 466                 queue->count ++;
 467         }
 468
 469         spin_unlock_irqrestore(&queue->lock, irqflags);
 470 }
 471
 472 static void rt2x00queue_reset(struct data_queue *queue)
 473 {
 474         unsigned long irqflags;
 475
 476         spin_lock_irqsave(&queue->lock, irqflags);
 477
 478         queue->count = 0;
 479         queue->length = 0;
 480         memset(queue->index, 0, sizeof(queue->index));
 481
 482         spin_unlock_irqrestore(&queue->lock, irqflags);
 483 }
 484
 485 void rt2x00queue_init_rx(struct rt2x00_dev *rt2x00dev)
 486 {
 487         struct data_queue *queue = rt2x00dev->rx;
 488         unsigned int i;
 489
 490         rt2x00queue_reset(queue);
 491
 492         if (!rt2x00dev->ops->lib->init_rxentry)
 493                 return;
 494
 495         for (i = 0; i < queue->limit; i++) {
 496                 queue->entries[i].flags = 0;
 497
 498                 rt2x00dev->ops->lib->init_rxentry(rt2x00dev,
 499                                                   &queue->entries[i]);
 500         }
 501 }
 502
 503 void rt2x00queue_init_tx(struct rt2x00_dev *rt2x00dev)
 504 {
 505         struct data_queue *queue;
 506         unsigned int i;
 507
 508         txall_queue_for_each(rt2x00dev, queue) {
 509                 rt2x00queue_reset(queue);
 510
 511                 if (!rt2x00dev->ops->lib->init_txentry)
 512                         continue;
 513
 514                 for (i = 0; i < queue->limit; i++) {
 515                         queue->entries[i].flags = 0;
 516
 517                         rt2x00dev->ops->lib->init_txentry(rt2x00dev,
 518                                                           &queue->entries[i]);
 519                 }
 520         }
 521 }
 522
 523 static int rt2x00queue_alloc_entries(struct data_queue *queue,
 524                                      const struct data_queue_desc *qdesc)
 525 {
 526         struct queue_entry *entries;
 527         unsigned int entry_size;
 528         unsigned int i;
 529
 530         rt2x00queue_reset(queue);
 531
 532         queue->limit = qdesc->entry_num;
 533         queue->threshold = DIV_ROUND_UP(qdesc->entry_num, 10);
 534         queue->data_size = qdesc->data_size;
 535         queue->desc_size = qdesc->desc_size;
 536
 537         /*
 538          * Allocate all queue entries.
 539          */
 540         entry_size = sizeof(*entries) + qdesc->priv_size;
 541         entries = kzalloc(queue->limit * entry_size, GFP_KERNEL);
 542         if (!entries)
 543                 return -ENOMEM;
 544
 545 #define QUEUE_ENTRY_PRIV_OFFSET(__base, __index, __limit, __esize, __psize) \
 546         ( ((char *)(__base)) + ((__limit) * (__esize)) + \
 547             ((__index) * (__psize)) )
 548
 549         for (i = 0; i < queue->limit; i++) {
 550                 entries[i].flags = 0;
 551                 entries[i].queue = queue;
 552                 entries[i].skb = NULL;
 553                 entries[i].entry_idx = i;
 554                 entries[i].priv_data =
 555                     QUEUE_ENTRY_PRIV_OFFSET(entries, i, queue->limit,
 556                                             sizeof(*entries), qdesc->priv_size);
 557         }
 558
 559 #undef QUEUE_ENTRY_PRIV_OFFSET
 560
 561         queue->entries = entries;
 562
 563         return 0;
 564 }
 565
 566 static void rt2x00queue_free_skbs(struct rt2x00_dev *rt2x00dev,
 567                                   struct data_queue *queue)
 568 {
 569         unsigned int i;
 570
 571         if (!queue->entries)
 572                 return;
 573
 574         for (i = 0; i < queue->limit; i++) {
 575                 if (queue->entries[i].skb)
 576                         rt2x00queue_free_skb(rt2x00dev, queue->entries[i].skb);
 577         }
 578 }
 579
 580 static int rt2x00queue_alloc_rxskbs(struct rt2x00_dev *rt2x00dev,
 581                                     struct data_queue *queue)
 582 {
 583         unsigned int i;
 584         struct sk_buff *skb;
 585
 586         for (i = 0; i < queue->limit; i++) {
 587                 skb = rt2x00queue_alloc_rxskb(rt2x00dev, &queue->entries[i]);
 588                 if (!skb)
 589                         return -ENOMEM;
 590                 queue->entries[i].skb = skb;
 591         }
 592
 593         return 0;
 594 }
 595
 596 int rt2x00queue_initialize(struct rt2x00_dev *rt2x00dev)
 597 {
 598         struct data_queue *queue;
 599         int status;
 600
 601         status = rt2x00queue_alloc_entries(rt2x00dev->rx, rt2x00dev->ops->rx);
 602         if (status)
 603                 goto exit;
 604
 605         tx_queue_for_each(rt2x00dev, queue) {
 606                 status = rt2x00queue_alloc_entries(queue, rt2x00dev->ops->tx);
 607                 if (status)
 608                         goto exit;
 609         }
 610
 611         status = rt2x00queue_alloc_entries(rt2x00dev->bcn, rt2x00dev->ops->bcn);
 612         if (status)
 613                 goto exit;
 614
 615         if (test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags)) {
 616                 status = rt2x00queue_alloc_entries(&rt2x00dev->bcn[1],
 617                                                    rt2x00dev->ops->atim);
 618                 if (status)
 619                         goto exit;
 620         }
 621
 622         status = rt2x00queue_alloc_rxskbs(rt2x00dev, rt2x00dev->rx);
 623         if (status)
 624                 goto exit;
 625
 626         return 0;
 627
 628 exit:
 629         ERROR(rt2x00dev, "Queue entries allocation failed.\n");
 630
 631         rt2x00queue_uninitialize(rt2x00dev);
 632
 633         return status;
 634 }
 635
 636 void rt2x00queue_uninitialize(struct rt2x00_dev *rt2x00dev)
 637 {
 638         struct data_queue *queue;
 639
 640         rt2x00queue_free_skbs(rt2x00dev, rt2x00dev->rx);
 641
 642         queue_for_each(rt2x00dev, queue) {
 643                 kfree(queue->entries);
 644                 queue->entries = NULL;
 645         }
 646 }
 647
 648 static void rt2x00queue_init(struct rt2x00_dev *rt2x00dev,
 649                              struct data_queue *queue, enum data_queue_qid qid)
 650 {
 651         spin_lock_init(&queue->lock);
 652
 653         queue->rt2x00dev = rt2x00dev;
 654         queue->qid = qid;
 655         queue->aifs = 2;
 656         queue->cw_min = 5;
 657         queue->cw_max = 10;
 658 }
 659
 660 int rt2x00queue_allocate(struct rt2x00_dev *rt2x00dev)
 661 {
 662         struct data_queue *queue;
 663         enum data_queue_qid qid;
 664         unsigned int req_atim =
 665             !!test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
 666
 667         /*
 668          * We need the following queues:
 669          * RX: 1
 670          * TX: ops->tx_queues
 671          * Beacon: 1
 672          * Atim: 1 (if required)
 673          */
 674         rt2x00dev->data_queues = 2 + rt2x00dev->ops->tx_queues + req_atim;
 675
 676         queue = kzalloc(rt2x00dev->data_queues * sizeof(*queue), GFP_KERNEL);
 677         if (!queue) {
 678                 ERROR(rt2x00dev, "Queue allocation failed.\n");
 679                 return -ENOMEM;
 680         }
 681
 682         /*
 683          * Initialize pointers
 684          */
 685         rt2x00dev->rx = queue;
 686         rt2x00dev->tx = &queue[1];
 687         rt2x00dev->bcn = &queue[1 + rt2x00dev->ops->tx_queues];
 688
 689         /*
 690          * Initialize queue parameters.
 691          * RX: qid = QID_RX
 692          * TX: qid = QID_AC_BE + index
 693          * TX: cw_min: 2^5 = 32.
 694          * TX: cw_max: 2^10 = 1024.
 695          * BCN: qid = QID_BEACON
 696          * ATIM: qid = QID_ATIM
 697          */
 698         rt2x00queue_init(rt2x00dev, rt2x00dev->rx, QID_RX);
 699
 700         qid = QID_AC_BE;
 701         tx_queue_for_each(rt2x00dev, queue)
 702                 rt2x00queue_init(rt2x00dev, queue, qid++);
 703
 704         rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[0], QID_BEACON);
 705         if (req_atim)
 706                 rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[1], QID_ATIM);
 707
 708         return 0;
 709 }
 710
 711 void rt2x00queue_free(struct rt2x00_dev *rt2x00dev)
 712 {
 713         kfree(rt2x00dev->rx);
 714         rt2x00dev->rx = NULL;
 715         rt2x00dev->tx = NULL;
 716         rt2x00dev->bcn = NULL;
 717 }