drivers/net/wireless/rt2x00/rt2x00mac.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: rt2x00mac
  23         Abstract: rt2x00 generic mac80211 routines.
  24  */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28
  29 #include "rt2x00.h"
  30 #include "rt2x00lib.h"
  31
  32 static int rt2x00mac_tx_rts_cts(struct rt2x00_dev *rt2x00dev,
  33                                 struct data_queue *queue,
  34                                 struct sk_buff *frag_skb)
  35 {
  36         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(frag_skb);
  37         struct skb_frame_desc *skbdesc;
  38         struct ieee80211_tx_info *rts_info;
  39         struct sk_buff *skb;
  40         int size;
  41
  42         if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
  43                 size = sizeof(struct ieee80211_cts);
  44         else
  45                 size = sizeof(struct ieee80211_rts);
  46
  47         skb = dev_alloc_skb(size + rt2x00dev->hw->extra_tx_headroom);
  48         if (!skb) {
  49                 WARNING(rt2x00dev, "Failed to create RTS/CTS frame.\n");
  50                 return NETDEV_TX_BUSY;
  51         }
  52
  53         skb_reserve(skb, rt2x00dev->hw->extra_tx_headroom);
  54         skb_put(skb, size);
  55
  56         /*
  57          * Copy TX information over from original frame to
  58          * RTS/CTS frame. Note that we set the no encryption flag
  59          * since we don't want this frame to be encrypted.
  60          * RTS frames should be acked, while CTS-to-self frames
  61          * should not. The ready for TX flag is cleared to prevent
  62          * it being automatically send when the descriptor is
  63          * written to the hardware.
  64          */
  65         memcpy(skb->cb, frag_skb->cb, sizeof(skb->cb));
  66         rts_info = IEEE80211_SKB_CB(skb);
  67         rts_info->flags |= IEEE80211_TX_CTL_DO_NOT_ENCRYPT;
  68         rts_info->flags &= ~IEEE80211_TX_CTL_USE_CTS_PROTECT;
  69         rts_info->flags &= ~IEEE80211_TX_CTL_REQ_TX_STATUS;
  70
  71         if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
  72                 rts_info->flags |= IEEE80211_TX_CTL_NO_ACK;
  73         else
  74                 rts_info->flags &= ~IEEE80211_TX_CTL_NO_ACK;
  75
  76         if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
  77                 ieee80211_ctstoself_get(rt2x00dev->hw, tx_info->control.vif,
  78                                         frag_skb->data, size, tx_info,
  79                                         (struct ieee80211_cts *)(skb->data));
  80         else
  81                 ieee80211_rts_get(rt2x00dev->hw, tx_info->control.vif,
  82                                   frag_skb->data, size, tx_info,
  83                                   (struct ieee80211_rts *)(skb->data));
  84
  85         /*
  86          * Initialize skb descriptor
  87          */
  88         skbdesc = get_skb_frame_desc(skb);
  89         memset(skbdesc, 0, sizeof(*skbdesc));
  90         skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
  91
  92         if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb)) {
  93                 WARNING(rt2x00dev, "Failed to send RTS/CTS frame.\n");
  94                 return NETDEV_TX_BUSY;
  95         }
  96
  97         return NETDEV_TX_OK;
  98 }
  99
 100 int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 101 {
 102         struct rt2x00_dev *rt2x00dev = hw->priv;
 103         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
 104         struct ieee80211_hdr *ieee80211hdr = (struct ieee80211_hdr *)skb->data;
 105         enum data_queue_qid qid = mac80211_queue_to_qid(tx_info->queue);
 106         struct data_queue *queue;
 107         u16 frame_control;
 108
 109         /*
 110          * Mac80211 might be calling this function while we are trying
 111          * to remove the device or perhaps suspending it.
 112          * Note that we can only stop the TX queues inside the TX path
 113          * due to possible race conditions in mac80211.
 114          */
 115         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags)) {
 116                 ieee80211_stop_queues(hw);
 117                 return NETDEV_TX_OK;
 118         }
 119
 120         /*
 121          * Determine which queue to put packet on.
 122          */
 123         if (tx_info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM &&
 124             test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags))
 125                 queue = rt2x00queue_get_queue(rt2x00dev, QID_ATIM);
 126         else
 127                 queue = rt2x00queue_get_queue(rt2x00dev, qid);
 128         if (unlikely(!queue)) {
 129                 ERROR(rt2x00dev,
 130                       "Attempt to send packet over invalid queue %d.\n"
 131                       "Please file bug report to %s.\n", qid, DRV_PROJECT);
 132                 dev_kfree_skb_any(skb);
 133                 return NETDEV_TX_OK;
 134         }
 135
 136         /*
 137          * If CTS/RTS is required. and this frame is not CTS or RTS,
 138          * create and queue that frame first. But make sure we have
 139          * at least enough entries available to send this CTS/RTS
 140          * frame as well as the data frame.
 141          * Note that when the driver has set the set_rts_threshold()
 142          * callback function it doesn't need software generation of
 143          * neither RTS or CTS-to-self frames and handles everything
 144          * inside the hardware.
 145          */
 146         frame_control = le16_to_cpu(ieee80211hdr->frame_control);
 147         if (!is_rts_frame(frame_control) && !is_cts_frame(frame_control) &&
 148             (tx_info->flags & (IEEE80211_TX_CTL_USE_RTS_CTS |
 149                                IEEE80211_TX_CTL_USE_CTS_PROTECT)) &&
 150             !rt2x00dev->ops->hw->set_rts_threshold) {
 151                 if (rt2x00queue_available(queue) <= 1) {
 152                         ieee80211_stop_queue(rt2x00dev->hw, tx_info->queue);
 153                         return NETDEV_TX_BUSY;
 154                 }
 155
 156                 if (rt2x00mac_tx_rts_cts(rt2x00dev, queue, skb)) {
 157                         ieee80211_stop_queue(rt2x00dev->hw, tx_info->queue);
 158                         return NETDEV_TX_BUSY;
 159                 }
 160         }
 161
 162         if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb)) {
 163                 ieee80211_stop_queue(rt2x00dev->hw, tx_info->queue);
 164                 return NETDEV_TX_BUSY;
 165         }
 166
 167         if (rt2x00queue_full(queue))
 168                 ieee80211_stop_queue(rt2x00dev->hw, tx_info->queue);
 169
 170         if (rt2x00dev->ops->lib->kick_tx_queue)
 171                 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, qid);
 172
 173         return NETDEV_TX_OK;
 174 }
 175 EXPORT_SYMBOL_GPL(rt2x00mac_tx);
 176
 177 int rt2x00mac_start(struct ieee80211_hw *hw)
 178 {
 179         struct rt2x00_dev *rt2x00dev = hw->priv;
 180
 181         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 182                 return 0;
 183
 184         return rt2x00lib_start(rt2x00dev);
 185 }
 186 EXPORT_SYMBOL_GPL(rt2x00mac_start);
 187
 188 void rt2x00mac_stop(struct ieee80211_hw *hw)
 189 {
 190         struct rt2x00_dev *rt2x00dev = hw->priv;
 191
 192         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 193                 return;
 194
 195         rt2x00lib_stop(rt2x00dev);
 196 }
 197 EXPORT_SYMBOL_GPL(rt2x00mac_stop);
 198
 199 int rt2x00mac_add_interface(struct ieee80211_hw *hw,
 200                             struct ieee80211_if_init_conf *conf)
 201 {
 202         struct rt2x00_dev *rt2x00dev = hw->priv;
 203         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
 204         struct data_queue *queue = rt2x00queue_get_queue(rt2x00dev, QID_BEACON);
 205         struct queue_entry *entry = NULL;
 206         unsigned int i;
 207
 208         /*
 209          * Don't allow interfaces to be added
 210          * the device has disappeared.
 211          */
 212         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
 213             !test_bit(DEVICE_STARTED, &rt2x00dev->flags))
 214                 return -ENODEV;
 215
 216         /*
 217          * We don't support mixed combinations of sta and ap virtual
 218          * interfaces. We can only add this interface when the rival
 219          * interface count is 0.
 220          */
 221         if ((conf->type == IEEE80211_IF_TYPE_AP && rt2x00dev->intf_sta_count) ||
 222             (conf->type != IEEE80211_IF_TYPE_AP && rt2x00dev->intf_ap_count))
 223                 return -ENOBUFS;
 224
 225         /*
 226          * Check if we exceeded the maximum amount of supported interfaces.
 227          */
 228         if ((conf->type == IEEE80211_IF_TYPE_AP &&
 229              rt2x00dev->intf_ap_count >= rt2x00dev->ops->max_ap_intf) ||
 230             (conf->type != IEEE80211_IF_TYPE_AP &&
 231              rt2x00dev->intf_sta_count >= rt2x00dev->ops->max_sta_intf))
 232                 return -ENOBUFS;
 233
 234         /*
 235          * Loop through all beacon queues to find a free
 236          * entry. Since there are as much beacon entries
 237          * as the maximum interfaces, this search shouldn't
 238          * fail.
 239          */
 240         for (i = 0; i < queue->limit; i++) {
 241                 entry = &queue->entries[i];
 242                 if (!__test_and_set_bit(ENTRY_BCN_ASSIGNED, &entry->flags))
 243                         break;
 244         }
 245
 246         if (unlikely(i == queue->limit))
 247                 return -ENOBUFS;
 248
 249         /*
 250          * We are now absolutely sure the interface can be created,
 251          * increase interface count and start initialization.
 252          */
 253
 254         if (conf->type == IEEE80211_IF_TYPE_AP)
 255                 rt2x00dev->intf_ap_count++;
 256         else
 257                 rt2x00dev->intf_sta_count++;
 258
 259         spin_lock_init(&intf->lock);
 260         intf->beacon = entry;
 261
 262         if (conf->type == IEEE80211_IF_TYPE_AP)
 263                 memcpy(&intf->bssid, conf->mac_addr, ETH_ALEN);
 264         memcpy(&intf->mac, conf->mac_addr, ETH_ALEN);
 265
 266         /*
 267          * The MAC adddress must be configured after the device
 268          * has been initialized. Otherwise the device can reset
 269          * the MAC registers.
 270          */
 271         rt2x00lib_config_intf(rt2x00dev, intf, conf->type, intf->mac, NULL);
 272
 273         /*
 274          * Some filters depend on the current working mode. We can force
 275          * an update during the next configure_filter() run by mac80211 by
 276          * resetting the current packet_filter state.
 277          */
 278         rt2x00dev->packet_filter = 0;
 279
 280         return 0;
 281 }
 282 EXPORT_SYMBOL_GPL(rt2x00mac_add_interface);
 283
 284 void rt2x00mac_remove_interface(struct ieee80211_hw *hw,
 285                                 struct ieee80211_if_init_conf *conf)
 286 {
 287         struct rt2x00_dev *rt2x00dev = hw->priv;
 288         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
 289
 290         /*
 291          * Don't allow interfaces to be remove while
 292          * either the device has disappeared or when
 293          * no interface is present.
 294          */
 295         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
 296             (conf->type == IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_ap_count) ||
 297             (conf->type != IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_sta_count))
 298                 return;
 299
 300         if (conf->type == IEEE80211_IF_TYPE_AP)
 301                 rt2x00dev->intf_ap_count--;
 302         else
 303                 rt2x00dev->intf_sta_count--;
 304
 305         /*
 306          * Release beacon entry so it is available for
 307          * new interfaces again.
 308          */
 309         __clear_bit(ENTRY_BCN_ASSIGNED, &intf->beacon->flags);
 310
 311         /*
 312          * Make sure the bssid and mac address registers
 313          * are cleared to prevent false ACKing of frames.
 314          */
 315         rt2x00lib_config_intf(rt2x00dev, intf,
 316                               IEEE80211_IF_TYPE_INVALID, NULL, NULL);
 317 }
 318 EXPORT_SYMBOL_GPL(rt2x00mac_remove_interface);
 319
 320 int rt2x00mac_config(struct ieee80211_hw *hw, struct ieee80211_conf *conf)
 321 {
 322         struct rt2x00_dev *rt2x00dev = hw->priv;
 323
 324         /*
 325          * Mac80211 might be calling this function while we are trying
 326          * to remove the device or perhaps suspending it.
 327          */
 328         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 329                 return 0;
 330
 331         /*
 332          * Check if we need to disable the radio,
 333          * if this is not the case, at least the RX must be disabled.
 334          */
 335         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags)) {
 336                 if (!conf->radio_enabled)
 337                         rt2x00lib_disable_radio(rt2x00dev);
 338                 else
 339                         rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_OFF);
 340         }
 341
 342         rt2x00lib_config(rt2x00dev, conf, 0);
 343
 344         /*
 345          * Reenable RX only if the radio should be on.
 346          */
 347         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags))
 348                 rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_ON);
 349         else if (conf->radio_enabled)
 350                 return rt2x00lib_enable_radio(rt2x00dev);
 351
 352         return 0;
 353 }
 354 EXPORT_SYMBOL_GPL(rt2x00mac_config);
 355
 356 int rt2x00mac_config_interface(struct ieee80211_hw *hw,
 357                                struct ieee80211_vif *vif,
 358                                struct ieee80211_if_conf *conf)
 359 {
 360         struct rt2x00_dev *rt2x00dev = hw->priv;
 361         struct rt2x00_intf *intf = vif_to_intf(vif);
 362         int status;
 363
 364         /*
 365          * Mac80211 might be calling this function while we are trying
 366          * to remove the device or perhaps suspending it.
 367          */
 368         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 369                 return 0;
 370
 371         spin_lock(&intf->lock);
 372
 373         /*
 374          * If the interface does not work in master mode,
 375          * then the bssid value in the interface structure
 376          * should now be set.
 377          */
 378         if (conf->type != IEEE80211_IF_TYPE_AP)
 379                 memcpy(&intf->bssid, conf->bssid, ETH_ALEN);
 380
 381         spin_unlock(&intf->lock);
 382
 383         /*
 384          * Call rt2x00_config_intf() outside of the spinlock context since
 385          * the call will sleep for USB drivers. By using the ieee80211_if_conf
 386          * values as arguments we make keep access to rt2x00_intf thread safe
 387          * even without the lock.
 388          */
 389         rt2x00lib_config_intf(rt2x00dev, intf, conf->type, NULL, conf->bssid);
 390
 391         /*
 392          * We only need to initialize the beacon when master mode is enabled.
 393          */
 394         if (conf->type != IEEE80211_IF_TYPE_AP || !conf->beacon)
 395                 return 0;
 396
 397         status = rt2x00dev->ops->hw->beacon_update(rt2x00dev->hw, conf->beacon);
 398         if (status)
 399                 dev_kfree_skb(conf->beacon);
 400
 401         return status;
 402 }
 403 EXPORT_SYMBOL_GPL(rt2x00mac_config_interface);
 404
 405 void rt2x00mac_configure_filter(struct ieee80211_hw *hw,
 406                                 unsigned int changed_flags,
 407                                 unsigned int *total_flags,
 408                                 int mc_count, struct dev_addr_list *mc_list)
 409 {
 410         struct rt2x00_dev *rt2x00dev = hw->priv;
 411
 412         /*
 413          * Mask off any flags we are going to ignore
 414          * from the total_flags field.
 415          */
 416         *total_flags &=
 417             FIF_ALLMULTI |
 418             FIF_FCSFAIL |
 419             FIF_PLCPFAIL |
 420             FIF_CONTROL |
 421             FIF_OTHER_BSS |
 422             FIF_PROMISC_IN_BSS;
 423
 424         /*
 425          * Apply some rules to the filters:
 426          * - Some filters imply different filters to be set.
 427          * - Some things we can't filter out at all.
 428          * - Multicast filter seems to kill broadcast traffic so never use it.
 429          */
 430         *total_flags |= FIF_ALLMULTI;
 431         if (*total_flags & FIF_OTHER_BSS ||
 432             *total_flags & FIF_PROMISC_IN_BSS)
 433                 *total_flags |= FIF_PROMISC_IN_BSS | FIF_OTHER_BSS;
 434
 435         /*
 436          * Check if there is any work left for us.
 437          */
 438         if (rt2x00dev->packet_filter == *total_flags)
 439                 return;
 440         rt2x00dev->packet_filter = *total_flags;
 441
 442         if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
 443                 rt2x00dev->ops->lib->config_filter(rt2x00dev, *total_flags);
 444         else
 445                 queue_work(rt2x00dev->hw->workqueue, &rt2x00dev->filter_work);
 446 }
 447 EXPORT_SYMBOL_GPL(rt2x00mac_configure_filter);
 448
 449 int rt2x00mac_get_stats(struct ieee80211_hw *hw,
 450                         struct ieee80211_low_level_stats *stats)
 451 {
 452         struct rt2x00_dev *rt2x00dev = hw->priv;
 453
 454         /*
 455          * The dot11ACKFailureCount, dot11RTSFailureCount and
 456          * dot11RTSSuccessCount are updated in interrupt time.
 457          * dot11FCSErrorCount is updated in the link tuner.
 458          */
 459         memcpy(stats, &rt2x00dev->low_level_stats, sizeof(*stats));
 460
 461         return 0;
 462 }
 463 EXPORT_SYMBOL_GPL(rt2x00mac_get_stats);
 464
 465 int rt2x00mac_get_tx_stats(struct ieee80211_hw *hw,
 466                            struct ieee80211_tx_queue_stats *stats)
 467 {
 468         struct rt2x00_dev *rt2x00dev = hw->priv;
 469         unsigned int i;
 470
 471         for (i = 0; i < rt2x00dev->ops->tx_queues; i++) {
 472                 stats[i].len = rt2x00dev->tx[i].length;
 473                 stats[i].limit = rt2x00dev->tx[i].limit;
 474                 stats[i].count = rt2x00dev->tx[i].count;
 475         }
 476
 477         return 0;
 478 }
 479 EXPORT_SYMBOL_GPL(rt2x00mac_get_tx_stats);
 480
 481 void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
 482                                 struct ieee80211_vif *vif,
 483                                 struct ieee80211_bss_conf *bss_conf,
 484                                 u32 changes)
 485 {
 486         struct rt2x00_dev *rt2x00dev = hw->priv;
 487         struct rt2x00_intf *intf = vif_to_intf(vif);
 488         unsigned int delayed = 0;
 489
 490         /*
 491          * When the association status has changed we must reset the link
 492          * tuner counter. This is because some drivers determine if they
 493          * should perform link tuning based on the number of seconds
 494          * while associated or not associated.
 495          */
 496         if (changes & BSS_CHANGED_ASSOC) {
 497                 rt2x00dev->link.count = 0;
 498
 499                 if (bss_conf->assoc)
 500                         rt2x00dev->intf_associated++;
 501                 else
 502                         rt2x00dev->intf_associated--;
 503
 504                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
 505                         rt2x00leds_led_assoc(rt2x00dev,
 506                                              !!rt2x00dev->intf_associated);
 507                 else
 508                         delayed |= DELAYED_LED_ASSOC;
 509         }
 510
 511         /*
 512          * When the erp information has changed, we should perform
 513          * additional configuration steps. For all other changes we are done.
 514          */
 515         if (changes & BSS_CHANGED_ERP_PREAMBLE) {
 516                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
 517                         rt2x00lib_config_erp(rt2x00dev, intf, bss_conf);
 518                 else
 519                         delayed |= DELAYED_CONFIG_ERP;
 520         }
 521
 522         spin_lock(&intf->lock);
 523         memcpy(&intf->conf, bss_conf, sizeof(*bss_conf));
 524         if (delayed) {
 525                 intf->delayed_flags |= delayed;
 526                 queue_work(rt2x00dev->hw->workqueue, &rt2x00dev->intf_work);
 527         }
 528         spin_unlock(&intf->lock);
 529 }
 530 EXPORT_SYMBOL_GPL(rt2x00mac_bss_info_changed);
 531
 532 int rt2x00mac_conf_tx(struct ieee80211_hw *hw, u16 queue_idx,
 533                       const struct ieee80211_tx_queue_params *params)
 534 {
 535         struct rt2x00_dev *rt2x00dev = hw->priv;
 536         struct data_queue *queue;
 537
 538         queue = rt2x00queue_get_queue(rt2x00dev, queue_idx);
 539         if (unlikely(!queue))
 540                 return -EINVAL;
 541
 542         /*
 543          * The passed variables are stored as real value ((2^n)-1).
 544          * Ralink registers require to know the bit number 'n'.
 545          */
 546         if (params->cw_min > 0)
 547                 queue->cw_min = fls(params->cw_min);
 548         else
 549                 queue->cw_min = 5; /* cw_min: 2^5 = 32. */
 550
 551         if (params->cw_max > 0)
 552                 queue->cw_max = fls(params->cw_max);
 553         else
 554                 queue->cw_max = 10; /* cw_min: 2^10 = 1024. */
 555
 556         if (params->aifs >= 0)
 557                 queue->aifs = params->aifs;
 558         else
 559                 queue->aifs = 2;
 560
 561         INFO(rt2x00dev,
 562              "Configured TX queue %d - CWmin: %d, CWmax: %d, Aifs: %d.\n",
 563              queue_idx, queue->cw_min, queue->cw_max, queue->aifs);
 564
 565         return 0;
 566 }
 567 EXPORT_SYMBOL_GPL(rt2x00mac_conf_tx);