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                                 struct ieee80211_tx_control *control)
  36 {
  37         struct skb_frame_desc *skbdesc;
  38         struct sk_buff *skb;
  39         int size;
  40
  41         if (control->flags & IEEE80211_TXCTL_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         if (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
  56                 ieee80211_ctstoself_get(rt2x00dev->hw, control->vif,
  57                                         frag_skb->data, frag_skb->len, control,
  58                                         (struct ieee80211_cts *)(skb->data));
  59         else
  60                 ieee80211_rts_get(rt2x00dev->hw, control->vif,
  61                                   frag_skb->data, frag_skb->len, control,
  62                                   (struct ieee80211_rts *)(skb->data));
  63
  64         /*
  65          * Initialize skb descriptor
  66          */
  67         skbdesc = get_skb_frame_desc(skb);
  68         memset(skbdesc, 0, sizeof(*skbdesc));
  69         skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
  70
  71         if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb, control)) {
  72                 WARNING(rt2x00dev, "Failed to send RTS/CTS frame.\n");
  73                 return NETDEV_TX_BUSY;
  74         }
  75
  76         return NETDEV_TX_OK;
  77 }
  78
  79 int rt2x00mac_tx(struct ieee80211_hw *hw, struct sk_buff *skb,
  80                  struct ieee80211_tx_control *control)
  81 {
  82         struct rt2x00_dev *rt2x00dev = hw->priv;
  83         struct ieee80211_hdr *ieee80211hdr = (struct ieee80211_hdr *)skb->data;
  84         struct data_queue *queue;
  85         struct skb_frame_desc *skbdesc;
  86         u16 frame_control;
  87
  88         /*
  89          * Mac80211 might be calling this function while we are trying
  90          * to remove the device or perhaps suspending it.
  91          * Note that we can only stop the TX queues inside the TX path
  92          * due to possible race conditions in mac80211.
  93          */
  94         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags)) {
  95                 ieee80211_stop_queues(hw);
  96                 dev_kfree_skb_any(skb);
  97                 return NETDEV_TX_OK;
  98         }
  99
 100         /*
 101          * Determine which queue to put packet on.
 102          */
 103         if (control->flags & IEEE80211_TXCTL_SEND_AFTER_DTIM &&
 104             test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags))
 105                 queue = rt2x00queue_get_queue(rt2x00dev, RT2X00_BCN_QUEUE_ATIM);
 106         else
 107                 queue = rt2x00queue_get_queue(rt2x00dev, control->queue);
 108         if (unlikely(!queue)) {
 109                 ERROR(rt2x00dev,
 110                       "Attempt to send packet over invalid queue %d.\n"
 111                       "Please file bug report to %s.\n",
 112                       control->queue, DRV_PROJECT);
 113                 dev_kfree_skb_any(skb);
 114                 return NETDEV_TX_OK;
 115         }
 116
 117         /*
 118          * If CTS/RTS is required. and this frame is not CTS or RTS,
 119          * create and queue that frame first. But make sure we have
 120          * at least enough entries available to send this CTS/RTS
 121          * frame as well as the data frame.
 122          */
 123         frame_control = le16_to_cpu(ieee80211hdr->frame_control);
 124         if (!is_rts_frame(frame_control) && !is_cts_frame(frame_control) &&
 125             (control->flags & (IEEE80211_TXCTL_USE_RTS_CTS |
 126                                IEEE80211_TXCTL_USE_CTS_PROTECT))) {
 127                 if (rt2x00queue_available(queue) <= 1) {
 128                         ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 129                         return NETDEV_TX_BUSY;
 130                 }
 131
 132                 if (rt2x00mac_tx_rts_cts(rt2x00dev, queue, skb, control)) {
 133                         ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 134                         return NETDEV_TX_BUSY;
 135                 }
 136         }
 137
 138         /*
 139          * Initialize skb descriptor
 140          */
 141         skbdesc = get_skb_frame_desc(skb);
 142         memset(skbdesc, 0, sizeof(*skbdesc));
 143
 144         if (rt2x00dev->ops->lib->write_tx_data(rt2x00dev, queue, skb, control)) {
 145                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 146                 return NETDEV_TX_BUSY;
 147         }
 148
 149         if (rt2x00queue_full(queue))
 150                 ieee80211_stop_queue(rt2x00dev->hw, control->queue);
 151
 152         if (rt2x00dev->ops->lib->kick_tx_queue)
 153                 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, control->queue);
 154
 155         return NETDEV_TX_OK;
 156 }
 157 EXPORT_SYMBOL_GPL(rt2x00mac_tx);
 158
 159 int rt2x00mac_start(struct ieee80211_hw *hw)
 160 {
 161         struct rt2x00_dev *rt2x00dev = hw->priv;
 162
 163         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 164                 return 0;
 165
 166         return rt2x00lib_start(rt2x00dev);
 167 }
 168 EXPORT_SYMBOL_GPL(rt2x00mac_start);
 169
 170 void rt2x00mac_stop(struct ieee80211_hw *hw)
 171 {
 172         struct rt2x00_dev *rt2x00dev = hw->priv;
 173
 174         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 175                 return;
 176
 177         rt2x00lib_stop(rt2x00dev);
 178 }
 179 EXPORT_SYMBOL_GPL(rt2x00mac_stop);
 180
 181 int rt2x00mac_add_interface(struct ieee80211_hw *hw,
 182                             struct ieee80211_if_init_conf *conf)
 183 {
 184         struct rt2x00_dev *rt2x00dev = hw->priv;
 185         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
 186         struct data_queue *queue =
 187             rt2x00queue_get_queue(rt2x00dev, RT2X00_BCN_QUEUE_BEACON);
 188         struct queue_entry *entry = NULL;
 189         unsigned int i;
 190
 191         /*
 192          * Don't allow interfaces to be added
 193          * the device has disappeared.
 194          */
 195         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
 196             !test_bit(DEVICE_STARTED, &rt2x00dev->flags))
 197                 return -ENODEV;
 198
 199         /*
 200          * When we don't support mixed interfaces (a combination
 201          * of sta and ap virtual interfaces) then we can only
 202          * add this interface when the rival interface count is 0.
 203          */
 204         if (!test_bit(DRIVER_SUPPORT_MIXED_INTERFACES, &rt2x00dev->flags) &&
 205             ((conf->type == IEEE80211_IF_TYPE_AP && rt2x00dev->intf_sta_count) ||
 206              (conf->type != IEEE80211_IF_TYPE_AP && rt2x00dev->intf_ap_count)))
 207                 return -ENOBUFS;
 208
 209         /*
 210          * Check if we exceeded the maximum amount of supported interfaces.
 211          */
 212         if ((conf->type == IEEE80211_IF_TYPE_AP &&
 213              rt2x00dev->intf_ap_count >= rt2x00dev->ops->max_ap_intf) ||
 214             (conf->type != IEEE80211_IF_TYPE_AP &&
 215              rt2x00dev->intf_sta_count >= rt2x00dev->ops->max_sta_intf))
 216                 return -ENOBUFS;
 217
 218         /*
 219          * Loop through all beacon queues to find a free
 220          * entry. Since there are as much beacon entries
 221          * as the maximum interfaces, this search shouldn't
 222          * fail.
 223          */
 224         for (i = 0; i < queue->limit; i++) {
 225                 entry = &queue->entries[i];
 226                 if (!__test_and_set_bit(ENTRY_BCN_ASSIGNED, &entry->flags))
 227                         break;
 228         }
 229
 230         if (unlikely(i == queue->limit))
 231                 return -ENOBUFS;
 232
 233         /*
 234          * We are now absolutely sure the interface can be created,
 235          * increase interface count and start initialization.
 236          */
 237
 238         if (conf->type == IEEE80211_IF_TYPE_AP)
 239                 rt2x00dev->intf_ap_count++;
 240         else
 241                 rt2x00dev->intf_sta_count++;
 242
 243         spin_lock_init(&intf->lock);
 244         intf->beacon = entry;
 245
 246         if (conf->type == IEEE80211_IF_TYPE_AP)
 247                 memcpy(&intf->bssid, conf->mac_addr, ETH_ALEN);
 248         memcpy(&intf->mac, conf->mac_addr, ETH_ALEN);
 249
 250         /*
 251          * The MAC adddress must be configured after the device
 252          * has been initialized. Otherwise the device can reset
 253          * the MAC registers.
 254          */
 255         rt2x00lib_config_intf(rt2x00dev, intf, conf->type, intf->mac, NULL);
 256
 257         /*
 258          * Some filters depend on the current working mode. We can force
 259          * an update during the next configure_filter() run by mac80211 by
 260          * resetting the current packet_filter state.
 261          */
 262         rt2x00dev->packet_filter = 0;
 263
 264         return 0;
 265 }
 266 EXPORT_SYMBOL_GPL(rt2x00mac_add_interface);
 267
 268 void rt2x00mac_remove_interface(struct ieee80211_hw *hw,
 269                                 struct ieee80211_if_init_conf *conf)
 270 {
 271         struct rt2x00_dev *rt2x00dev = hw->priv;
 272         struct rt2x00_intf *intf = vif_to_intf(conf->vif);
 273
 274         /*
 275          * Don't allow interfaces to be remove while
 276          * either the device has disappeared or when
 277          * no interface is present.
 278          */
 279         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
 280             (conf->type == IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_ap_count) ||
 281             (conf->type != IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_sta_count))
 282                 return;
 283
 284         if (conf->type == IEEE80211_IF_TYPE_AP)
 285                 rt2x00dev->intf_ap_count--;
 286         else
 287                 rt2x00dev->intf_sta_count--;
 288
 289         /*
 290          * Release beacon entry so it is available for
 291          * new interfaces again.
 292          */
 293         __clear_bit(ENTRY_BCN_ASSIGNED, &intf->beacon->flags);
 294
 295         /*
 296          * Make sure the bssid and mac address registers
 297          * are cleared to prevent false ACKing of frames.
 298          */
 299         rt2x00lib_config_intf(rt2x00dev, intf,
 300                               IEEE80211_IF_TYPE_INVALID, NULL, NULL);
 301 }
 302 EXPORT_SYMBOL_GPL(rt2x00mac_remove_interface);
 303
 304 int rt2x00mac_config(struct ieee80211_hw *hw, struct ieee80211_conf *conf)
 305 {
 306         struct rt2x00_dev *rt2x00dev = hw->priv;
 307
 308         /*
 309          * Mac80211 might be calling this function while we are trying
 310          * to remove the device or perhaps suspending it.
 311          */
 312         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 313                 return 0;
 314
 315         /*
 316          * Check if we need to disable the radio,
 317          * if this is not the case, at least the RX must be disabled.
 318          */
 319         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags)) {
 320                 if (!conf->radio_enabled)
 321                         rt2x00lib_disable_radio(rt2x00dev);
 322                 else
 323                         rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_OFF);
 324         }
 325
 326         rt2x00lib_config(rt2x00dev, conf, 0);
 327
 328         /*
 329          * Reenable RX only if the radio should be on.
 330          */
 331         if (test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags))
 332                 rt2x00lib_toggle_rx(rt2x00dev, STATE_RADIO_RX_ON);
 333         else if (conf->radio_enabled)
 334                 return rt2x00lib_enable_radio(rt2x00dev);
 335
 336         return 0;
 337 }
 338 EXPORT_SYMBOL_GPL(rt2x00mac_config);
 339
 340 int rt2x00mac_config_interface(struct ieee80211_hw *hw,
 341                                struct ieee80211_vif *vif,
 342                                struct ieee80211_if_conf *conf)
 343 {
 344         struct rt2x00_dev *rt2x00dev = hw->priv;
 345         struct rt2x00_intf *intf = vif_to_intf(vif);
 346         int status;
 347
 348         /*
 349          * Mac80211 might be calling this function while we are trying
 350          * to remove the device or perhaps suspending it.
 351          */
 352         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
 353                 return 0;
 354
 355         spin_lock(&intf->lock);
 356
 357         /*
 358          * If the interface does not work in master mode,
 359          * then the bssid value in the interface structure
 360          * should now be set.
 361          */
 362         if (conf->type != IEEE80211_IF_TYPE_AP)
 363                 memcpy(&intf->bssid, conf->bssid, ETH_ALEN);
 364
 365         spin_unlock(&intf->lock);
 366
 367         /*
 368          * Call rt2x00_config_intf() outside of the spinlock context since
 369          * the call will sleep for USB drivers. By using the ieee80211_if_conf
 370          * values as arguments we make keep access to rt2x00_intf thread safe
 371          * even without the lock.
 372          */
 373         rt2x00lib_config_intf(rt2x00dev, intf, conf->type, NULL, conf->bssid);
 374
 375         /*
 376          * We only need to initialize the beacon when master mode is enabled.
 377          */
 378         if (conf->type != IEEE80211_IF_TYPE_AP || !conf->beacon)
 379                 return 0;
 380
 381         status = rt2x00dev->ops->hw->beacon_update(rt2x00dev->hw,
 382                                                    conf->beacon,
 383                                                    conf->beacon_control);
 384         if (status)
 385                 dev_kfree_skb(conf->beacon);
 386
 387         return status;
 388 }
 389 EXPORT_SYMBOL_GPL(rt2x00mac_config_interface);
 390
 391 void rt2x00mac_configure_filter(struct ieee80211_hw *hw,
 392                                 unsigned int changed_flags,
 393                                 unsigned int *total_flags,
 394                                 int mc_count, struct dev_addr_list *mc_list)
 395 {
 396         struct rt2x00_dev *rt2x00dev = hw->priv;
 397
 398         /*
 399          * Mask off any flags we are going to ignore
 400          * from the total_flags field.
 401          */
 402         *total_flags &=
 403             FIF_ALLMULTI |
 404             FIF_FCSFAIL |
 405             FIF_PLCPFAIL |
 406             FIF_CONTROL |
 407             FIF_OTHER_BSS |
 408             FIF_PROMISC_IN_BSS;
 409
 410         /*
 411          * Apply some rules to the filters:
 412          * - Some filters imply different filters to be set.
 413          * - Some things we can't filter out at all.
 414          * - Multicast filter seems to kill broadcast traffic so never use it.
 415          */
 416         *total_flags |= FIF_ALLMULTI;
 417         if (*total_flags & FIF_OTHER_BSS ||
 418             *total_flags & FIF_PROMISC_IN_BSS)
 419                 *total_flags |= FIF_PROMISC_IN_BSS | FIF_OTHER_BSS;
 420
 421         /*
 422          * Check if there is any work left for us.
 423          */
 424         if (rt2x00dev->packet_filter == *total_flags)
 425                 return;
 426         rt2x00dev->packet_filter = *total_flags;
 427
 428         if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
 429                 rt2x00dev->ops->lib->config_filter(rt2x00dev, *total_flags);
 430         else
 431                 queue_work(rt2x00dev->workqueue, &rt2x00dev->filter_work);
 432 }
 433 EXPORT_SYMBOL_GPL(rt2x00mac_configure_filter);
 434
 435 int rt2x00mac_get_stats(struct ieee80211_hw *hw,
 436                         struct ieee80211_low_level_stats *stats)
 437 {
 438         struct rt2x00_dev *rt2x00dev = hw->priv;
 439
 440         /*
 441          * The dot11ACKFailureCount, dot11RTSFailureCount and
 442          * dot11RTSSuccessCount are updated in interrupt time.
 443          * dot11FCSErrorCount is updated in the link tuner.
 444          */
 445         memcpy(stats, &rt2x00dev->low_level_stats, sizeof(*stats));
 446
 447         return 0;
 448 }
 449 EXPORT_SYMBOL_GPL(rt2x00mac_get_stats);
 450
 451 int rt2x00mac_get_tx_stats(struct ieee80211_hw *hw,
 452                            struct ieee80211_tx_queue_stats *stats)
 453 {
 454         struct rt2x00_dev *rt2x00dev = hw->priv;
 455         unsigned int i;
 456
 457         for (i = 0; i < hw->queues; i++) {
 458                 stats->data[i].len = rt2x00dev->tx[i].length;
 459                 stats->data[i].limit = rt2x00dev->tx[i].limit;
 460                 stats->data[i].count = rt2x00dev->tx[i].count;
 461         }
 462
 463         return 0;
 464 }
 465 EXPORT_SYMBOL_GPL(rt2x00mac_get_tx_stats);
 466
 467 void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
 468                                 struct ieee80211_vif *vif,
 469                                 struct ieee80211_bss_conf *bss_conf,
 470                                 u32 changes)
 471 {
 472         struct rt2x00_dev *rt2x00dev = hw->priv;
 473         struct rt2x00_intf *intf = vif_to_intf(vif);
 474         unsigned int delayed = 0;
 475
 476         /*
 477          * When the association status has changed we must reset the link
 478          * tuner counter. This is because some drivers determine if they
 479          * should perform link tuning based on the number of seconds
 480          * while associated or not associated.
 481          */
 482         if (changes & BSS_CHANGED_ASSOC) {
 483                 rt2x00dev->link.count = 0;
 484
 485                 if (bss_conf->assoc)
 486                         rt2x00dev->intf_associated++;
 487                 else
 488                         rt2x00dev->intf_associated--;
 489
 490                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
 491                         rt2x00leds_led_assoc(rt2x00dev,
 492                                              !!rt2x00dev->intf_associated);
 493                 else
 494                         delayed |= DELAYED_LED_ASSOC;
 495         }
 496
 497         /*
 498          * When the erp information has changed, we should perform
 499          * additional configuration steps. For all other changes we are done.
 500          */
 501         if (changes & BSS_CHANGED_ERP_PREAMBLE) {
 502                 if (!test_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags))
 503                         rt2x00lib_config_erp(rt2x00dev, intf, bss_conf);
 504                 else
 505                         delayed |= DELAYED_CONFIG_ERP;
 506         }
 507
 508         spin_lock(&intf->lock);
 509         memcpy(&intf->conf, bss_conf, sizeof(*bss_conf));
 510         if (delayed) {
 511                 intf->delayed_flags |= delayed;
 512                 queue_work(rt2x00dev->workqueue, &rt2x00dev->intf_work);
 513         }
 514         spin_unlock(&intf->lock);
 515 }
 516 EXPORT_SYMBOL_GPL(rt2x00mac_bss_info_changed);
 517
 518 int rt2x00mac_conf_tx(struct ieee80211_hw *hw, int queue_idx,
 519                       const struct ieee80211_tx_queue_params *params)
 520 {
 521         struct rt2x00_dev *rt2x00dev = hw->priv;
 522         struct data_queue *queue;
 523
 524         queue = rt2x00queue_get_queue(rt2x00dev, queue_idx);
 525         if (unlikely(!queue))
 526                 return -EINVAL;
 527
 528         /*
 529          * The passed variables are stored as real value ((2^n)-1).
 530          * Ralink registers require to know the bit number 'n'.
 531          */
 532         if (params->cw_min > 0)
 533                 queue->cw_min = fls(params->cw_min);
 534         else
 535                 queue->cw_min = 5; /* cw_min: 2^5 = 32. */
 536
 537         if (params->cw_max > 0)
 538                 queue->cw_max = fls(params->cw_max);
 539         else
 540                 queue->cw_max = 10; /* cw_min: 2^10 = 1024. */
 541
 542         if (params->aifs >= 0)
 543                 queue->aifs = params->aifs;
 544         else
 545                 queue->aifs = 2;
 546
 547         INFO(rt2x00dev,
 548              "Configured TX queue %d - CWmin: %d, CWmax: %d, Aifs: %d.\n",
 549              queue_idx, queue->cw_min, queue->cw_max, queue->aifs);
 550
 551         return 0;
 552 }
 553 EXPORT_SYMBOL_GPL(rt2x00mac_conf_tx);