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 ieee80211_tx_info *rts_info;
  38         struct sk_buff *skb;
  39         int size;
  40
  41         if (tx_info->flags & IEEE80211_TX_CTL_USE_CTS_PROTECT)
  42                 size = sizeof(struct ieee80211_cts);
  43         else
  44                 size = sizeof(struct ieee80211_rts);
  45
  46         skb = dev_alloc_skb(size + rt2x00dev->hw->extra_tx_headroom);
  47         if (!skb) {
  48                 WARNING(rt2x00dev, "Failed to create RTS/CTS frame.\n");
  49                 return NETDEV_TX_BUSY;
  50         }
  51
  52         skb_reserve(skb, rt2x00dev->hw->extra_tx_headroom);
  53         skb_put(skb, size);
  54
  55         /*
  56          * Copy TX information over from original frame to
  57          * RTS/CTS frame. Note that we set the no encryption flag
  58          * since we don't want this frame to be encrypted.
  59          * RTS frames should be acked, while CTS-to-self frames
  60          * should not. The ready for TX flag is cleared to prevent
  61          * it being automatically send when the descriptor is
  62          * written to the hardware.
  63          */
  64         memcpy(skb->cb, frag_skb->cb, sizeof(skb->cb));
  65         rts_info = IEEE80211_SKB_CB(skb);
  66         rts_info->control.hw_key = NULL;
  67         rts_info->flags &= ~IEEE80211_TX_CTL_USE_RTS_CTS;
  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         if (rt2x00queue_write_tx_frame(queue, skb)) {
  86                 dev_kfree_skb_any(skb);
  87                 WARNING(rt2x00dev, "Failed to send RTS/CTS frame.\n");
  88                 return NETDEV_TX_BUSY;
  89         }
  90
  91         return NETDEV_TX_OK;
  92 }
  93
  94 int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
  95 {
  96         struct rt2x00_dev *rt2x00dev = hw->priv;
  97         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
  98         struct ieee80211_hdr *ieee80211hdr = (struct ieee80211_hdr *)skb->data;
  99         enum data_queue_qid qid = skb_get_queue_mapping(skb);
 100         struct data_queue *queue;
 101         u16 frame_control;
 102
 103         /*
 104          * Mac80211 might be calling this function while we are trying
 105          * to remove the device or perhaps suspending it.
 106          * Note that we can only stop the TX queues inside the TX path
 107          * due to possible race conditions in mac80211.
 108          */
 109         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags)) {
 110                 ieee80211_stop_queues(hw);
 111                 dev_kfree_skb_any(skb);
 112                 return NETDEV_TX_OK;
 113         }
 114
 115         /*
 116          * Determine which queue to put packet on.
 117          */
 118         if (tx_info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM &&
 119             test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags))
 120                 queue = rt2x00queue_get_queue(rt2x00dev, QID_ATIM);
 121         else
 122                 queue = rt2x00queue_get_queue(rt2x00dev, qid);
 123         if (unlikely(!queue)) {
 124                 ERROR(rt2x00dev,
 125                       "Attempt to send packet over invalid queue %d.\n"
 126                       "Please file bug report to %s.\n", qid, DRV_PROJECT);
 127                 dev_kfree_skb_any(skb);
 128                 return NETDEV_TX_OK;
 129         }
 130
 131         /*
 132          * If CTS/RTS is required. create and queue that frame first.
 133          * Make sure we have at least enough entries available to send
 134          * this CTS/RTS frame as well as the data frame.
 135          * Note that when the driver has set the set_rts_threshold()
 136          * callback function it doesn't need software generation of
 137          * either RTS or CTS-to-self frame and handles everything
 138          * inside the hardware.
 139          */
 140         frame_control = le16_to_cpu(ieee80211hdr->frame_control);
 141         if ((tx_info->flags & (IEEE80211_TX_CTL_USE_RTS_CTS |
 142                                IEEE80211_TX_CTL_USE_CTS_PROTECT)) &&
 143             !rt2x00dev->ops->hw->set_rts_threshold) {
 144                 if (rt2x00queue_available(queue) <= 1) {
 145                         ieee80211_stop_queue(rt2x00dev->hw, qid);
 146                         return NETDEV_TX_BUSY;
 147                 }
 148
 149                 if (rt2x00mac_tx_rts_cts(rt2x00dev, queue, skb)) {
 150                         ieee80211_stop_queue(rt2x00dev->hw, qid);
 151                         return NETDEV_TX_BUSY;
 152                 }
 153         }
 154
 155         if (rt2x00queue_write_tx_frame(queue, skb)) {
 156                 ieee80211_stop_queue(rt2x00dev->hw, qid);
 157                 return NETDEV_TX_BUSY;
 158         }
 159
 160         if (rt2x00queue_threshold(queue))
 161                 ieee80211_stop_queue(rt2x00dev->hw, qid);
 162
 163         return NETDEV_TX_OK;
 164 }
 165 EXPORT_SYMBOL_GPL(rt2x00mac_tx);
 166
 167 int rt2x00mac_start(struct ieee80211_hw *hw)
 168 {
 169         struct rt2x00_dev *rt2x00dev = hw->priv;
 170
 171         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 172                 return 0;
 173
 174         return rt2x00lib_start(rt2x00dev);
 175 }
 176 EXPORT_SYMBOL_GPL(rt2x00mac_start);
 177
 178 void rt2x00mac_stop(struct ieee80211_hw *hw)
 179 {
 180         struct rt2x00_dev *rt2x00dev = hw->priv;
 181
 182         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 183                 return;
 184
 185         rt2x00lib_stop(rt2x00dev);
 186 }
 187 EXPORT_SYMBOL_GPL(rt2x00mac_stop);
 188
 189 int rt2x00mac_add_interface(struct ieee80211_hw *hw,
 190                             struct ieee80211_if_init_conf *conf)
 191 {
 192         struct rt2x00_dev *rt2x00dev = hw->priv;
 193         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
 194         struct data_queue *queue = rt2x00queue_get_queue(rt2x00dev, QID_BEACON);
 195         struct queue_entry *entry = NULL;
 196         unsigned int i;
 197
 198         /*
 199          * Don't allow interfaces to be added
 200          * the device has disappeared.
 201          */
 202         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
 203             !test_bit(DEVICE_STARTED, &rt2x00dev->flags))
 204                 return -ENODEV;
 205
 206         switch (conf->type) {
 207         case IEEE80211_IF_TYPE_AP:
 208                 /*
 209                  * We don't support mixed combinations of
 210                  * sta and ap interfaces.
 211                  */
 212                 if (rt2x00dev->intf_sta_count)
 213                         return -ENOBUFS;
 214
 215                 /*
 216                  * Check if we exceeded the maximum amount
 217                  * of supported interfaces.
 218                  */
 219                 if (rt2x00dev->intf_ap_count >= rt2x00dev->ops->max_ap_intf)
 220                         return -ENOBUFS;
 221
 222                 break;
 223         case IEEE80211_IF_TYPE_STA:
 224         case IEEE80211_IF_TYPE_IBSS:
 225                 /*
 226                  * We don't support mixed combinations of
 227                  * sta and ap interfaces.
 228                  */
 229                 if (rt2x00dev->intf_ap_count)
 230                         return -ENOBUFS;
 231
 232                 /*
 233                  * Check if we exceeded the maximum amount
 234                  * of supported interfaces.
 235                  */
 236                 if (rt2x00dev->intf_sta_count >= rt2x00dev->ops->max_sta_intf)
 237                         return -ENOBUFS;
 238
 239                 break;
 240         default:
 241                 return -EINVAL;
 242         }
 243
 244         /*
 245          * Loop through all beacon queues to find a free
 246          * entry. Since there are as much beacon entries
 247          * as the maximum interfaces, this search shouldn't
 248          * fail.
 249          */
 250         for (i = 0; i < queue->limit; i++) {
 251                 entry = &queue->entries[i];
 252                 if (!__test_and_set_bit(ENTRY_BCN_ASSIGNED, &entry->flags))
 253                         break;
 254         }
 255
 256         if (unlikely(i == queue->limit))
 257                 return -ENOBUFS;
 258
 259         /*
 260          * We are now absolutely sure the interface can be created,
 261          * increase interface count and start initialization.
 262          */
 263
 264         if (conf->type == IEEE80211_IF_TYPE_AP)
 265                 rt2x00dev->intf_ap_count++;
 266         else
 267                 rt2x00dev->intf_sta_count++;
 268
 269         spin_lock_init(&intf->lock);
 270         spin_lock_init(&intf->seqlock);
 271         intf->beacon = entry;
 272
 273         if (conf->type == IEEE80211_IF_TYPE_AP)
 274                 memcpy(&intf->bssid, conf->mac_addr, ETH_ALEN);
 275         memcpy(&intf->mac, conf->mac_addr, ETH_ALEN);
 276
 277         /*
 278          * The MAC adddress must be configured after the device
 279          * has been initialized. Otherwise the device can reset
 280          * the MAC registers.
 281          */
 282         rt2x00lib_config_intf(rt2x00dev, intf, conf->type, intf->mac, NULL);
 283
 284         /*
 285          * Some filters depend on the current working mode. We can force
 286          * an update during the next configure_filter() run by mac80211 by
 287          * resetting the current packet_filter state.
 288          */
 289         rt2x00dev->packet_filter = 0;
 290
 291         return 0;
 292 }
 293 EXPORT_SYMBOL_GPL(rt2x00mac_add_interface);
 294
 295 void rt2x00mac_remove_interface(struct ieee80211_hw *hw,
 296                                 struct ieee80211_if_init_conf *conf)
 297 {
 298         struct rt2x00_dev *rt2x00dev = hw->priv;
 299         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
 300
 301         /*
 302          * Don't allow interfaces to be remove while
 303          * either the device has disappeared or when
 304          * no interface is present.
 305          */
 306         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
 307             (conf->type == IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_ap_count) ||
 308             (conf->type != IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_sta_count))
 309                 return;
 310
 311         if (conf->type == IEEE80211_IF_TYPE_AP)
 312                 rt2x00dev->intf_ap_count--;
 313         else
 314                 rt2x00dev->intf_sta_count--;
 315
 316         /*
 317          * Release beacon entry so it is available for
 318          * new interfaces again.
 319          */
 320         __clear_bit(ENTRY_BCN_ASSIGNED, &intf->beacon->flags);
 321
 322         /*
 323          * Make sure the bssid and mac address registers
 324          * are cleared to prevent false ACKing of frames.
 325          */
 326         rt2x00lib_config_intf(rt2x00dev, intf,
 327                               IEEE80211_IF_TYPE_INVALID, NULL, NULL);
 328 }
 329 EXPORT_SYMBOL_GPL(rt2x00mac_remove_interface);
 330
 331 int rt2x00mac_config(struct ieee80211_hw *hw, struct ieee80211_conf *conf)
 332 {
 333         struct rt2x00_dev *rt2x00dev = hw->priv;
 334         int force_reconfig;
 335
 336         /*
 337          * Mac80211 might be calling this function while we are trying
 338          * to remove the device or perhaps suspending it.
 339          */
 340         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 341                 return 0;
 342
 343         /*
 344          * Check if we need to disable the radio,
 345          * if this is not the case, at least the RX must be disabled.
 346          */
 347         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags)) {
 348                 if (!conf->radio_enabled)
 349                         rt2x00lib_disable_radio(rt2x00dev);
 350                 else
 351                         rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_OFF);
 352         }
 353
 354         /*
 355          * When the DEVICE_DIRTY_CONFIG flag is set, the device has recently
 356          * been started and the configuration must be forced upon the hardware.
 357          * Otherwise registers will not be intialized correctly and could
 358          * result in non-working hardware because essential registers aren't
 359          * initialized.
 360          */
 361         force_reconfig =
 362             __test_and_clear_bit(DEVICE_DIRTY_CONFIG, &rt2x00dev->flags);
 363
 364         rt2x00lib_config(rt2x00dev, conf, force_reconfig);
 365
 366         /*
 367          * Reenable RX only if the radio should be on.
 368          */
 369         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags))
 370                 rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_ON);
 371         else if (conf->radio_enabled)
 372                 return rt2x00lib_enable_radio(rt2x00dev);
 373
 374         return 0;
 375 }
 376 EXPORT_SYMBOL_GPL(rt2x00mac_config);
 377
 378 int rt2x00mac_config_interface(struct ieee80211_hw *hw,
 379                                struct ieee80211_vif *vif,
 380                                struct ieee80211_if_conf *conf)
 381 {
 382         struct rt2x00_dev *rt2x00dev = hw->priv;
 383         struct rt2x00_intf *intf = vif_to_intf(vif);
 384         int update_bssid = 0;
 385         int status = 0;
 386
 387         /*
 388          * Mac80211 might be calling this function while we are trying
 389          * to remove the device or perhaps suspending it.
 390          */
 391         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 392                 return 0;
 393
 394         spin_lock(&intf->lock);
 395
 396         /*
 397          * conf->bssid can be NULL if coming from the internal
 398          * beacon update routine.
 399          */
 400         if (conf->changed & IEEE80211_IFCC_BSSID && conf->bssid) {
 401                 update_bssid = 1;
 402                 memcpy(&intf->bssid, conf->bssid, ETH_ALEN);
 403         }
 404
 405         spin_unlock(&intf->lock);
 406
 407         /*
 408          * Call rt2x00_config_intf() outside of the spinlock context since
 409          * the call will sleep for USB drivers. By using the ieee80211_if_conf
 410          * values as arguments we make keep access to rt2x00_intf thread safe
 411          * even without the lock.
 412          */
 413         rt2x00lib_config_intf(rt2x00dev, intf, vif->type, NULL,
 414                               update_bssid ? conf->bssid : NULL);
 415
 416         /*
 417          * Update the beacon.
 418          */
 419         if (conf->changed & IEEE80211_IFCC_BEACON)
 420                 status = rt2x00queue_update_beacon(rt2x00dev, vif);
 421
 422         return status;
 423 }
 424 EXPORT_SYMBOL_GPL(rt2x00mac_config_interface);
 425
 426 void rt2x00mac_configure_filter(struct ieee80211_hw *hw,
 427                                 unsigned int changed_flags,
 428                                 unsigned int *total_flags,
 429                                 int mc_count, struct dev_addr_list *mc_list)
 430 {
 431         struct rt2x00_dev *rt2x00dev = hw->priv;
 432
 433         /*
 434          * Mask off any flags we are going to ignore
 435          * from the total_flags field.
 436          */
 437         *total_flags &=
 438             FIF_ALLMULTI |
 439             FIF_FCSFAIL |
 440             FIF_PLCPFAIL |
 441             FIF_CONTROL |
 442             FIF_OTHER_BSS |
 443             FIF_PROMISC_IN_BSS;
 444
 445         /*
 446          * Apply some rules to the filters:
 447          * - Some filters imply different filters to be set.
 448          * - Some things we can't filter out at all.
 449          * - Multicast filter seems to kill broadcast traffic so never use it.
 450          */
 451         *total_flags |= FIF_ALLMULTI;
 452         if (*total_flags & FIF_OTHER_BSS ||
 453             *total_flags & FIF_PROMISC_IN_BSS)
 454                 *total_flags |= FIF_PROMISC_IN_BSS | FIF_OTHER_BSS;
 455
 456         /*
 457          * Check if there is any work left for us.
 458          */
 459         if (rt2x00dev->packet_filter == *total_flags)
 460                 return;
 461         rt2x00dev->packet_filter = *total_flags;
 462
 463         if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
 464                 rt2x00dev->ops->lib->config_filter(rt2x00dev, *total_flags);
 465         else
 466                 queue_work(rt2x00dev->hw->workqueue, &rt2x00dev->filter_work);
 467 }
 468 EXPORT_SYMBOL_GPL(rt2x00mac_configure_filter);
 469
 470 int rt2x00mac_get_stats(struct ieee80211_hw *hw,
 471                         struct ieee80211_low_level_stats *stats)
 472 {
 473         struct rt2x00_dev *rt2x00dev = hw->priv;
 474
 475         /*
 476          * The dot11ACKFailureCount, dot11RTSFailureCount and
 477          * dot11RTSSuccessCount are updated in interrupt time.
 478          * dot11FCSErrorCount is updated in the link tuner.
 479          */
 480         memcpy(stats, &rt2x00dev->low_level_stats, sizeof(*stats));
 481
 482         return 0;
 483 }
 484 EXPORT_SYMBOL_GPL(rt2x00mac_get_stats);
 485
 486 int rt2x00mac_get_tx_stats(struct ieee80211_hw *hw,
 487                            struct ieee80211_tx_queue_stats *stats)
 488 {
 489         struct rt2x00_dev *rt2x00dev = hw->priv;
 490         unsigned int i;
 491
 492         for (i = 0; i < rt2x00dev->ops->tx_queues; i++) {
 493                 stats[i].len = rt2x00dev->tx[i].length;
 494                 stats[i].limit = rt2x00dev->tx[i].limit;
 495                 stats[i].count = rt2x00dev->tx[i].count;
 496         }
 497
 498         return 0;
 499 }
 500 EXPORT_SYMBOL_GPL(rt2x00mac_get_tx_stats);
 501
 502 void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
 503                                 struct ieee80211_vif *vif,
 504                                 struct ieee80211_bss_conf *bss_conf,
 505                                 u32 changes)
 506 {
 507         struct rt2x00_dev *rt2x00dev = hw->priv;
 508         struct rt2x00_intf *intf = vif_to_intf(vif);
 509         unsigned int delayed = 0;
 510
 511         /*
 512          * When the association status has changed we must reset the link
 513          * tuner counter. This is because some drivers determine if they
 514          * should perform link tuning based on the number of seconds
 515          * while associated or not associated.
 516          */
 517         if (changes & BSS_CHANGED_ASSOC) {
 518                 rt2x00dev->link.count = 0;
 519
 520                 if (bss_conf->assoc)
 521                         rt2x00dev->intf_associated++;
 522                 else
 523                         rt2x00dev->intf_associated--;
 524
 525                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
 526                         rt2x00leds_led_assoc(rt2x00dev,
 527                                              !!rt2x00dev->intf_associated);
 528                 else
 529                         delayed |= DELAYED_LED_ASSOC;
 530         }
 531
 532         /*
 533          * When the erp information has changed, we should perform
 534          * additional configuration steps. For all other changes we are done.
 535          */
 536         if (changes & (BSS_CHANGED_ERP_PREAMBLE | BSS_CHANGED_ERP_CTS_PROT)) {
 537                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
 538                         rt2x00lib_config_erp(rt2x00dev, intf, bss_conf);
 539                 else
 540                         delayed |= DELAYED_CONFIG_ERP;
 541         }
 542
 543         spin_lock(&intf->lock);
 544         memcpy(&intf->conf, bss_conf, sizeof(*bss_conf));
 545         if (delayed) {
 546                 intf->delayed_flags |= delayed;
 547                 schedule_work(&rt2x00dev->intf_work);
 548         }
 549         spin_unlock(&intf->lock);
 550 }
 551 EXPORT_SYMBOL_GPL(rt2x00mac_bss_info_changed);
 552
 553 int rt2x00mac_conf_tx(struct ieee80211_hw *hw, u16 queue_idx,
 554                       const struct ieee80211_tx_queue_params *params)
 555 {
 556         struct rt2x00_dev *rt2x00dev = hw->priv;
 557         struct data_queue *queue;
 558
 559         queue = rt2x00queue_get_queue(rt2x00dev, queue_idx);
 560         if (unlikely(!queue))
 561                 return -EINVAL;
 562
 563         /*
 564          * The passed variables are stored as real value ((2^n)-1).
 565          * Ralink registers require to know the bit number 'n'.
 566          */
 567         if (params->cw_min > 0)
 568                 queue->cw_min = fls(params->cw_min);
 569         else
 570                 queue->cw_min = 5; /* cw_min: 2^5 = 32. */
 571
 572         if (params->cw_max > 0)
 573                 queue->cw_max = fls(params->cw_max);
 574         else
 575                 queue->cw_max = 10; /* cw_min: 2^10 = 1024. */
 576
 577         queue->aifs = params->aifs;
 578
 579         INFO(rt2x00dev,
 580              "Configured TX queue %d - CWmin: %d, CWmax: %d, Aifs: %d.\n",
 581              queue_idx, queue->cw_min, queue->cw_max, queue->aifs);
 582
 583         return 0;
 584 }
 585 EXPORT_SYMBOL_GPL(rt2x00mac_conf_tx);